Engines.

Available only in the Japanese market is the SR20VET that produces 206 kW (280 ps) and is used in the X-Trail GT. The Australian model is powered by a QR25DE 2.5 L four cylinder engine initially producing 132 kW (177 hp). From January 2006, the Australian spec engine was detuned to 123 kW (169 hp). Also available is the QR20DE four cylinder engine, producing 103 kW (140 hp) or 110 kW (150 hp) with manual or automatic transmission.  The biggest selling engine in the United Kingdom is the YD22DDTi, a 2.2 litre turbocharged common rail diesel.  The X-Trail has had three model revisions, the Series 1 and Series 2 (using Nissan FF-S platform) and the Series 3 (using Nissan/Renault C platform). There were various cosmetic and engineering changes made between Series 1 and 2, but the Series 3 T31 is all new despite a similar appearance with new engines apart from the 2.5L which has been retained.

First generation (T30; 2000).

The T30 series X-Trail was unveiled at the September 2000 Paris Motor Show. It uses the Nissan FF-S platform, shared with the Nissan Almera and the Nissan Primera. It entered production in October, and sales in Japan commenced in November 2000.  The X-Trail was sold in Canada for the model years of 2005 and 2006 (but Nissan Canada continued to market it until 2007), and in Mexico since 2003. It has been sold in the Philippines since the middle of 2003. In 2007 Nissan introduced the newly remodeled X-Trail T31 model major interior and exterior changes and two turbo diesel 2.0 CC turbo inter-cooler offering 150 bhp or 177bhp with greater fuel efficiency this was the most comprehensive redesign until the release of a completely new X-Trail in 2013 T-32  In the United Kingdom, the first generation car was available in S, Sport and SE+ between launch and 2004. There was also a FatFace model in 2005, also for the United Kingdom, which was based on the model Sports. They made 1998 of them to celebrate the year FatFace was set up. The trim levels were then revised to SE, Sport, SVE and T-Spec.  In Australia, it was available in standard ST, mid spec ST-S, high spec Ti and luxury spec Ti-L, with limited editions ST-X, ST-R, ST-S 40th anniversary models. At this point, all models in the United Kingdom were equipped with full electric windows, electricity adjustable door mirrors (on SVE and T-Spec they were electrically folding also), climate control, single CD player, four airbags and remote central locking.  While in Australia all models were equipped with full electric windows, electric mirrors (electric folding on Ti-L), single CD player, two airbags and remote central locking. ST-S adds ST on sunroof and 16" alloy wheels. Ti adds ST on climate control, six disk CD player, fog lamps and 16" alloy wheels, and Ti-L adds Ti on leather and electric seats, sunroof, and optional DVD player. Limited edition ST-R adds ST on light emitting roof racks, with "ST-S 40th Anniversary" adding fog lamps to original ST-S.  2007 Nissan released its completely upgraded X-Trail T31. Nissan replacing the Nissan X-Trail T30. This new newly redesigned T31 X-Trail offers 3 motor options petrol and 2 diesel fuel efficient diesel replacing the old 2.2 CC dCI with 2.0 CC dCI 150bhp and 177bhp. This new design once again put Nissan ahead of its competitors offering a sleek new body and more power with many more options.

GT.

From mid 2002 to 2009, Nissan launched a special edition X-Trail equipped with the SR20VET petrol turbocharged engine, which produces. Named the X-Trail GT, it was offered only in Japan.

Taiwan.

In 2003, Taiwanese Nissan distributor Yulon launched the Nissan X-Trail with a major design difference in the front end compared to the international version to fit the taste of the Taiwanese market. The design was done by Yulon Asia Technical Center under Yulon-Nissan Motors. The model was sold until 2006, when it received a minor facelift with new front bumper, grilles, headlamps, and LED tail lamps.  Due to the late facelift, Yulon-Nissan skipped the second generation X-Trail and continued the production of the facelifted Taiwanese Nissan X-Trail until 2008 and was replaced by the American imported first generation Nissan Rogue. The X-Trail nameplate did not return until 2015 when the third generation Nissan X-Trail returned and continued to be domestically produced in Taiwan.  In 2006, Nissan Canada launched a Nissan X-Trail Bonavista Edition commercial, featuring a Nissan dealer speaking in an incomprehensible Newfoundland accent. The commercial itself backfired when Bonavista Mayor Betty Fitzgerald claimed it had portrayed people in Bonavista as people who cannot speak properly. To further expose the commercial's lack of linguistic authenticity, CBC News reported the sales rep was played by an actor from Cape Breton. That commercial was parodied by a local car dealer in St. John's, Newfoundland and Labrador, in a radio advert that takes shots at Ontario marketing companies and Premier Dalton McGuinty's "nondescript" personality.

Gallery.

Pre-facelift styling Post-facelift styling Taiwanese market pre-facelift styling Taiwanese market facelift styling

Second generation (T31; 2007).

The 2008 Nissan X-Trail had its public debut at the Geneva Motor Show in March 2007, and went on sale in Japan in August 2007, Europe in the third quarter of that year, and Australia and Mexico towards the end of the year. Slightly larger than the previous model, it is based on the Nissan C platform. The second generation was not sold in the United States and Canada, where it was instead replaced by the Rogue.  The X-Trail GT SR20VET petrol turbocharged engine was not offered in the second generation X-Trail, due to the 2005 Japan vehicle emissions control. In September 2008, the 20GT became available in Japan, equipped with the M9R, a 2.0 litre turbocharged common rail diesel engine developed jointly with Renault. This was the first diesel X-Trail offered in the Japanese domestic market.  A facelift second generation was released in Japan in July 2010. The Nissan X-Trail Platinum, with special features not seen on any other X-Trail, was released in a limited run of 200 vehicles for the United Kingdom in January 2012.  The second generation was replaced in October 2013, when the third generation X-Trail was unveiled in Japan. Only petrol engine variants were initially offered for Japan, with the diesel-engined second generation continuing to be available for the domestic market.  The second generation was released in Malaysia in 2010, where it was fully imported from Indonesia. Only one variant was made available, which consisted of the MR20DE engine paired to a CVT transmission. The facelift version was made available in Malaysia in April 2013.

Gallery.

Dongfeng Fengdu MX6.

In March 2015, models went on sale in China from Dongfeng Nissan Passenger Vehicle Company (DFL-PV), badged as Dongfeng Fengdu MX6, with 4WD and 2WD models available. The 2.0 litre MR20DE engine is standard along with a six speed manual or CVT gearbox. Trim levels are Standard, Excellence and Premium. Prices started from 122,800 to 169,800 yuan ($19,760 – 27,330). The Dongfeng Fengdu MX6 is a rebadged version of the Nissan X-Trail T31, featuring restyled front and rear bumpers produced by Zhengzhou-Nissan, and branded under the Dongfeng-Fengdu sub-brand of Dongfeng Motor Corporation.

Third generation (T32; 2013).

Based on the jointly developed Nissan/Renault Common Module Family (CMF) platform architecture, the third generation model incorporates styling cues from the Qashqai, Murano, and Patrol. Japanese production of the third generation X-Trail originates from the Nissan Motor Kyushu Co., Ltd. factory. Production also began in Saint Petersburg, Russia.  The vehicle was unveiled at the 2013 Frankfurt Motor Show and was inspired by the Hi-Cross Concept, followed by the 43rd Tokyo Motor Show 2013, and the 2014 Geneva Motor Show.

Markets.

Asia.

Japanese sales commenced on December 11, 2013. Early models include MR20DD engine with Idling Stop (20S, 20X, 20X Emergency Brake package, 20X X-TREMER X, 20X Emergency Brake Package X-TREMER X), XTRONIC CVT, ALL MODE 4X4-i system for 4WD models, 2 or 3 (except 20S) rows of seats.  Autech Japan produced the X-TRAIL X-TREMER Package Stretched (2014): a concept vehicle based on Nissan X-Trail 20X X-TREMER X, with accessory parts and dedicated paint along with bold exterior features such as over fenders. The vehicle was unveiled at the 2014 Tokyo Auto Salon.  Chinese models went on sale from Dongfeng Nissan Passenger Vehicle Company (DFL-PV) in the end of March 2014.  On September 12, 2014, prior to the Indonesia International Motor Show 2014, Nissan Motor Indonesia launched the third generation Nissan X-Trail. It is only available with three rows of seats in five variants: 2.0 MT, 2.0 CVT with the MR20DD engine, 2.5 CVT using the QR25DE engine, X-Trail XTREMER based on X-Trail 2.5 CVT and X-Trail Hybrid.  It is manufactured in Purwakarta, Indonesia primarily for domestic demand and was also launched in Thailand in November 2014 and it is manufactured in Samut Prakan, Thailand for Thai domestic demand. In December 2014, Autech Japan produced the limited edition X-TRAIL 20X BLACK X-TREMER X for the JDM.  In the Philippines, the third generation X-Trail was launched on 19 September 2014 during the 5th Philippine International Motor Show and is offered in two variants; 2.0L 2WD CVT and 2.5L 4WD CVT. The facelifted X-Trail was launched in the Philippines in September 2017. Engine choices remained the same as the pre-facelift model. It was also launched in Thailand in February 2019 where consumers had the choice between several variants powered by either a 2.5L petrol engine or a 2.0L hybrid powertrain.  The facelifted X-Trail was also launched in Indonesia on July 18, 2019 at the 27th Gaikindo Indonesia International Auto Show, and went on sale in August 2019. It is only available in VL trim and powered by a 2.5L petrol engine with CVT.  In April 2015, Nissan announced that an X-Trail hybrid with claimed fuel economy of 4.9 l/100 km was coming to Japan.  For the Malaysian market, the third generation X-Trail was launched in January 2015 with two variants: 2.0L 2WD (CVT) or 2.5L 4WD (CVT). Since launch, various editions have been made available namely Impul, Aero Edition and X-Tremer. All the various editions were/are sold alongside the regular X-Trail and like the regular X-Trail are available with either a 2.0L 2WD or 2.5L 4WD.  In March 2019, bookings were opened for the facelifted X-Trail with a media preview happening in March 2019 as well. The facelifted X-Trail has been available in Malaysia since April 2019.and available with four variants: 2.5S 2WD, 2.5V 4WD, 2.0V 4WD Hybrid and 2.0VL 4WD Hybrid.

Australia.

Australian models went on sale in March 2014 with both petrol and diesel variants: ST 2.0 2WD 6-speed Manual, ST, ST-L and Ti 2.5 CVT and TS 1.6 dCi 2WD CVT, TS 1.6 dCi 4WD CVT, TL 1.6 dCi 2WD CVT and TL 1.6 dCi 4WD 6-speed manual. On ST and ST-L 2.5, third row seats are available. European models went on sale in July 2014, with the only engine available being a Renault sourced 1.6 dCi R9M diesel engine with CVT or 6-speed Manual.

Facelift.

For 2017, the Nissan X-Trail has been facelifted, with restyled headlights and taillights which includes, restyled twin LED projector headlamps with High intensity discharge and LED Daytime Running Lights, which is now offered on SL trim levels with the Premium Package, while S, SV trim levels, and the SL trim levels without the Premium Package offers Halogen Headlamps with LED daytime running lights, and LED taillights are available on all trim levels. The 2.5L engine with 170 hp carries over from the previous model.  The new X-Trail went on sale in October 2016, and also has exterior and interior colours. A hybrid version of the vehicle premiered in January 2017 (Limited Availability) for the 2017 model year.  The hybrid features regenerative braking, pure drive hybrid emblems, energy monitor, hybrid battery status, under floor storage area replacing Divide-N-Hide@ Cargo System, a 2.0 litre four cylinder gasoline engine (power: 141 hp and torque: 141 lb-ft) and Xtronic CVT combined with an electric motor (power: 40 hp) and Lithium-Ion battery, for a combined power of 176 hp.  The Lithium-Ion battery is located below the thick flooring of the under floor cargo storage area. The X-Trail Hybrid is available in two trim levels, SV and SL, but the Nissan X-Trail Hybrid will not be available with Third Row Seating (Family Package) and Divide-N-Hide@ Cargo System, due to the Lithium-Ion battery.

Production.

On October 27, 2016, Nissan Motor Corporation announced the production of the next X-Trail at NMUK. In February 2019, these plans were cancelled, with production planned to remain in Japan, citing concerns about Brexit related uncertainty. The declining popularity of diesel cars was another factor.  Nissan's Sunderland plant in the United Kingdom has been in operation since 1986, and has around 7,000 employees. Sunderland will continue to manufacture several Nissan models and the company reaffirmed its commitment to manufacture the new Qashqai for 2020 at the plant in the United Kingdom.  Both Nissan and British officials confirmed that no jobs would be lost due to the modified arrangement, which will see production of the X-Trail moved to Kyushu.

The is a compact crossover SUV produced by the Japanese automaker Nissan since 2000. In third generation, it is a three row SUV.

La Nissan X-Trail est un modèle de SUV compact produit par le constructeur automobile japonais Nissan depuis 2001. À ce jour, trois générations se sont succédé, la dernière en date est maintenant considérée comme un crossover de taille moyenne. Il fut le premier SUV de la marque Nissan, et leur première entrée sur le marché très compétitif du SUV, puisque d'autres modèles, venus d'autres constructeurs automobiles, étaient proposés dans la même période, tels que la Suzuki Grand Vitara, la Hyundai Tucson, la Honda CR-V et la Toyota RAV4.


Structure and properties.

Structure.

SDS is in the family of organosulfate compounds, and has the formula,. It consists of a 12-carbon tail attached to a sulfate group, that is, it is the sodium salt of a 12-carbon alcohol that has been esterified to sulfuric acid. An alternative description is that it is an alkyl group with a pendant, terminal sulfate group attached. As a result of its hydrocarbon tail, and its anionic "head group", it has amphiphilic properties that allow it to form micelles, and so act as a detergent.

Physicochemical properties.

The critical micelle concentration (CMC) in pure water at 25 °C is 8.2 mM, and the aggregation number at this concentration is usually considered to be about 62. The micelle ionization fraction (α) is around 0.3 (or 30%).

Production.

SDS is synthesized by treating lauryl alcohol with sulfur trioxide gas, oleum, or chlorosulfuric acid to produce hydrogen lauryl sulfate. The resulting product is then neutralized through the addition of sodium hydroxide or sodium carbonate. Lauryl alcohol can be used in pure form or may be derived from either coconut or palm kernel oil by hydrolysis (which liberates their fatty acids), followed by hydrogenation. When produced from these sources, commercial samples of these "SDS" products are actually not pure SDS, rather a mixture of various sodium alkyl sulfates with SDS being the main component. For instance, SDS is a component, along with other chain-length amphiphiles, when produced from coconut oil, and is known as sodium coco sulfate (SCS). SDS is available commercially in powder, pellet, and other forms (each differing in rates of dissolution), as well as in aqueous solutions of varying concentrations.

Applications.

Cleaning and hygiene.

SDS is mainly used in detergents for laundry with many cleaning applications. It is a highly effective surfactant and is used in any task requiring the removal of oily stains and residues; for example, it is found in higher concentrations with industrial products including engine degreasers, floor cleaners, and car exterior cleaners.  In lower concentrations, it is found in hand soap, toothpastes, shampoos, shaving creams, and bubble bath formulations, for its ability to create a foam (lather), for its surfactant properties, and in part for its thickening effect.

Food additive.

Sodium dodecyl sulfate, appearing as its synonym "sodium lauryl sulfate" (SLS), is considered a generally recognized as safe (GRAS) ingredient for food use according to the USFDA (21 CFR 172.822). It is used as an emulsifying agent and whipping aid. SLS is reported to temporarily diminish perception of sweetness.

Laboratory applications.

Principal applications.

Sodium lauryl sulfate, in science referred to as sodium "dodecyl" sulfate (SDS), is used in cleaning procedures, and is commonly used as a component for lysing cells during RNA extraction and/or DNA extraction, and for denaturing proteins in preparation for electrophoresis in the SDS-PAGE technique.  In the case of the SDS-PAGE application, the compound works by disrupting non-covalent bonds in the proteins, and so denaturing them, i.e., causing the protein molecules to lose their native conformations and shapes. By binding to the proteins with high affinity and in high concentrations, the negatively charged detergent provides all proteins with a similar net negative charge and therefore a similar charge-to-mass ratio. In this way, the difference in mobility of the polypeptide chains in the gel can be attributed solely to their size as opposed to both their size and charge. It is possible to make separation based on the size of the polypeptide chain to simplify the analysis of protein molecules, this can be achieved by denaturing proteins with the detergent SDS. The association of SDS molecules with protein molecules imparts an associated negative charge to the molecular aggregate formed; this negative charge is significantly greater than the original charge of that protein. The electrostatic repulsion that is created by SDS binding forces proteins into a rod-like shape, thereby eliminating differences in shape as a factor for electrophoretic separation in gels. A dodecyl sulfate molecule has two negative charges at the pH value used for electrophoresis, this will lead the net charge of coated polypeptide chains to be much more negative than uncoated chains. The charge-to-mass ratio is essentially identical for different proteins because SDS coating dominates the charge.

Miscellaneous applications.

SDS is used in an improved technique for preparing brain tissues for study by optical microscopy. The technique, which has been branded as CLARITY, was the work of Karl Deisseroth and coworkers at Stanford University, and involves infusion of the organ with an acrylamide solution to bind the macromolecules of the organ (proteins, nucleic acids, etc.), followed by thermal polymerization to form a "brain–hydrogel" (a mesh interspersed throughout the tissue to fix the macromolecules and other structures in space), and then by lipid removal using SDS to eliminate light scattering with minimal protein loss, rendering the tissue quasi-transparent.  Along with sodium dodecylbenzene sulfonate and Triton X-100, aqueous solutions of SDS are popular for dispersing or suspending nanotubes, such as carbon nanotubes.

Niche uses.

SDS has been proposed as a potentially effective topical microbicide, for intravaginal use, to inhibit and possibly prevent infection by various enveloped and non-enveloped viruses such as the herpes simplex viruses, HIV, and the Semliki Forest virus.  In gas hydrate formation experiments, SDS is used as a gas hydrate growth promoter. Researchers aim for gas hydrate promotions as scale-up of industrial applications of gas hydrates such as desalination process, gas storage, and gas separation technologies.  Liquid membranes formed from SDS in water have been demonstrated to work as unusual particle separators. The device acts as a reverse filter, allowing large particles to pass while capturing smaller particles.

Toxicology.

Carcinogenicity.

SDS is not carcinogenic when consumed or applied directly, even to amounts and concentrations that exceed amounts used in standard commercial products. The earlier review of the Cosmetic Ingredient Review (CIR) program Expert Panel in 1983 reported that SDS (there, abbreviated SLS, for sodium lauryl sulfate) in concentrations up to 2%, in a year-long oral dietary studies in dogs, gave no evidence of tumorigenicity or carcinogenicity, and that no excess chromosomal aberrations or clastogenic effects were observed in rats fed up to 1.13% sodium lauryl sulfate in their diets for 90 days, over those on a control diet. The 2005 review by the same group indicated that further available data lacked any available suggestion that SDS or the related ammonium salt of the same amphiphile could be carcinogenic, stating that "Despite assertions to the contrary on the Internet, the carcinogenicity of these ingredients is only a rumor;" both studies conclude that SDS appears "to be safe in formulations designed for discontinuous, brief use followed by thorough rinsing from the surface of the skin. In products intended for prolonged contact with skin, concentrations should not exceed 1%."

Sensitivity.

Like all detergents, sodium lauryl sulfate removes oils from the skin, and can cause skin and eye irritation. It has been shown to irritate the skin of the face, with prolonged and constant exposure (more than an hour) in young adults. SDS may worsen skin problems in individuals with chronic skin hypersensitivity, with some people being affected more than others.

Oral concerns.

The low cost of SDS, its lack of impact on taste, its potential impact on volatile sulfur compounds (VSCs), which contribute to malodorous breath, and its desirable action as a foaming agent have led to the use of SDS in the formulations of toothpastes. A series of small crossover studies (25-34 patients) have supported the efficacy of SLS in the reduction of VSCs, and its related positive impact on breath malodor, although these studies have been generally noted to reflect technical challenges in the control of study design variables. While primary sources from the group of Irma Rantanen at University of Turku, Finland conclude an impact on dry mouth (xerostomia) from SLS-containing pastes, a 2011 Cochrane review of these studies, and of the more general area, concludes that there "is no strong evidence... that any topical therapy is effective for relieving the symptom of dry mouth." A safety concern has been raised on the basis of several studies regarding the effect of toothpaste SDS on aphthous ulcers, commonly referred to as canker or white sores. A consensus regarding practice (or change in practice) has not appeared as a result of the studies. As Lippert notes, of 2013, "very few... marketed toothpastes contain a surfactant other than SLS [SDS]," and leading manufacturers continue to formulate their produce with SDS.

Interaction with fluoride.

Some studies have suggested that SLS in toothpaste may decrease the effectiveness of fluoride at preventing dental caries (cavities). This may be due to SLS interacting with the deposition of fluoride on tooth enamel.

Sodium dodecyl sulfate (SDS) or sodium lauryl sulfate (SLS), sometimes written sodium laurilsulfate, is a synthetic organic compound with the formula. It is an anionic surfactant used in many cleaning and hygiene products. This molecule is an organosulfate and a salt. It consists of a 12-carbon tail attached to a sulfate group, that is, it is the sodium salt of "dodecyl hydrogen sulfate," the ester of dodecyl alcohol and sulfuric acid. Its hydrocarbon tail combined with a polar "headgroup" give the compound amphiphilic properties and so make it useful as a detergent. Also derived as a component of mixtures produced from inexpensive coconut and palm oils, SDS is a common component of many domestic cleaning, personal hygiene and cosmetic, pharmaceutical, and food products, as well as of industrial and commercial cleaning and product formulations.

Le laurylsulfate de sodium (LSS) ou dodécylsulfate de sodium (SDS), plus connu sous sa dénomination INCI sodium lauryl sulfate ou SLS, est un détergent et tensioactif ionique fort, couramment utilisé en biochimie et biologie moléculaire.


Biography.

Childhood.

She was born Aleksandra Aleksandrovna Grigorovich in Białystok, in the Grodno Governorate of the Russian Empire (now Poland) to a wealthy Belarusian family. Her father, Aleksandr Grigorovich, was a wealthy Belarusian businessman. Her mother was Greek. Young Aleksandra received an excellent private education, studying languages, music, art, and taking private drawing lessons. Soon her parents moved to Kyiv (Kiev), and Asya, as called by her friends, attended Kiev gymnasium St. Olga and Kiev Art School, where she studied with Alexander Bogomazov and Alexander Archipenko. Her teachers included Mykola Pymonenko. Aleksandra graduated in painting from Kiev Art School in 1906.

Marriage.

In 1908, Aleksandra Grigorovich married a successful Kiev lawyer, Nikolai Evgenyevich Ekster. The Eksters belonged to cultural and intellectual elite of Kiev. She spent several months with her husband in Paris, and there she attended Académie de la Grande Chaumière in Montparnasse. From 1908 to 1924 she intermittently lived in Kiev, St. Petersburg, Odessa, Paris, Rome and Moscow.

Kiev.

Her painting studio in the attic at 27 Funduklievskaya Street, now Khmelnytsky Street, was a rallying stage for Kiev's intellectual elite. In the attic in her studio there worked future luminaries of world decorative art Vadim Meller, Anatole Petrytsky and P. Tchelitchew. There she was visited by poets and writers, such as Anna Akhmatova, Ilia Ehrenburg, and Osip Mandelstam, dancers Bronislava Nijinska and Elsa Kruger, as well as many artists Alexander Bogomazov, Wladimir Baranoff-Rossine, and students, such as Grigori Kozintsev, Sergei Yutkevich, and Aleksei Kapler among many others. In 1908 she participated in an exhibition together with members of the group "Zveno (Link)" organized by David Burliuk, Wladimir Burliuk and others in Kiev.

Paris.

In Paris, Aleksandra Ekster became personally acquainted with Pablo Picasso and Georges Braque, who introduced her to Gertrude Stein.  She exhibited six works at the Salon de la Section d'Or, Galerie La Boétie, Paris, October 1912, with Jean Metzinger, Albert Gleizes, Marcel Duchamp and others.  In 1914, Ekster participated in the "Salon des Indépendants" exhibitions in Paris, together with Kazimir Malevich, Alexander Archipenko, Vadym Meller, Sonia Delaunay-Terk and other French and Russian artists. In that same year she participated with the "Russians" Archipenko, Koulbine and Rozanova in the "International Futurist Exhibition" in Rome. In 1915 she joined the group of avant-garde artists "Supremus". Her friend introduced her to the poet Apollinaire, who took her to Picasso's workshop. According to Moscow Chamber Theatre actress Alice Coonen, "In [Ekster's] Parisian household there was a conspicuous peculiar combination of European culture with Ukrainian life. On the walls between Picasso and Braque paintings there was Ukrainian embroidery; on the floor was a Ukrainian carpet, at the table they served clay pots, colorful majolica plates of dumplings."

Russian avant-garde.

Under the avant-guard umbrella, Ekster has been noted to be a suprematist and constructivist painter as well as a major influencer of the Art Deco movement.  While not confined within a particular movement, Ekster was one of the most experimental women of the avant-garde. Ekster absorbed from many sources and cultures in order to develop her own original style. In 1915–1916 she worked in the peasant craft cooperatives in the villages Skoptsi and Verbovka along with Kazimir Malevich, Yevgenia Pribylskaya, Natalia Davidova, Nina Genke, Liubov Popova, Ivan Puni, Olga Rozanova, Nadezhda Udaltsova and others. Ekster later founded a teaching and production workshop (MDI) in Kiev (1918–1920). Vadym Meller, Anatol Petrytsky, Kliment Red'ko, Tchelitchew, Shifrin, Nikritin worked there. Also during this period she was one of the leading stage designers of Alexander Tairov's Chamber Theatre.  In 1919 together with other avant-garde artists Kliment Red'ko and Nina Genke-Meller she decorated the streets and squares of Kiev and Odessa in abstract style for Revolution Festivities. She worked with Vadym Meller as a costume designer in a ballet studio of the dancer Bronislava Nijinska.  In 1921 she became a director of the elementary course "Color" at the Higher Artistic-Technical Workshop (VKhUTEMAS) in Moscow, a position she held until 1924. Her work was displayed alongside that of other Constructivist artists at the "5x5=25" exhibition held in Moscow in 1921.  In line with her eclectic avant-guard-like style, Ekster's early paintings strongly influenced her costume design as well as her book illustrations, which are scarcely noted. All of Ekster's works, no matter the medium, stick to her distinct style. Her works are vibrant, playful, dramatic, and theatrical in composition, subject matter, and color. Ekster constantly stayed true to her composition aesthetic across all mediums. Furthermore, each medium only enhanced and influenced her work in other mediums. With her assimilation of many different genres her essential futurist and cubist ideas was always in tandem with her attention to colour and rhythm. Ekster uses many elements of geometric compositions, which reinforce the core intentions of dynamism, vibrant contrasts, and free brushwork. Ekster stretched the dynamic intentions of her work across all mediums. Ekster's theatrical works such as sculptures, costume design, set design, and decorations for the revolutionary festivals, strongly reflect her work with geometric elements and vibrant intentions. Through her costume work she experimented with the transparency, movement, and vibrancy of fabrics. Ekster's movement of her brushstroke in her artwork is reflected in the movement of the fabric in her costumes. Ekster's theatrical sets used multi-coloured dimensions and experimented with spatial structures. She continued with these experimental tendencies in her later puppet designs. With her experimentation across many mediums Ekster started to take the concept of her costume designing and integrate it into everyday life. In 1921 Ekster's work in fashion design began. Though her mass production designs were wearable, most of her fashion design was highly decorative and innovative, usually falling under the category of haute couture.  In 1923, she continued her work in many media in addition to collaborating with Vera Mukhina and Boris Gladkov in Moscow on the decor of the All Russian Exhibition pavilions.

Emigration.

In 1924 Aleksandra Ekster and her husband emigrated to France and settled in Paris, where she initially became a professor at the "Academie Moderne". From 1926 to 1930 Ekster was a professor at Fernand Léger's Académie d'Art Contemporain. In 1933 she began creating beautiful and original illuminated manuscripts (gouache on paper), perhaps the most important works of the last phase of her life. The "Callimaque" manuscript (c. 1939, the text being a French translation of a hymn by Hellenistic poet Callimachus) is widely regarded as her masterpiece. In 1936 she participated in the exhibition "Cubism and Abstract Art" in New York and went on to have solo exhibitions in Prague and in Paris. She was a book illustrator for the publishing company "Flammarion" in Paris from 1936 until her death in the Paris suburb of Fontenay-aux-Roses. During the past few decades her reputation has increased dramatically, as have the prices of her works. As a consequence, several fakes have appeared on the market in recent years.

Aleksandra Aleksandrovna Ekster (, ; 18 January 1882 – 17 March 1949), also known as Alexandra Exter, was a Russian Cubo-Futurist, Suprematist, Constructivist painter and designer of international stature who divided her life between Kiev, St. Petersburg, Moscow, Vienna, and Paris.

Alexandra Exter (en, en ), née Alexandra Alexandrovna Grigorovitch à Belostok (Empire russe, actuellement en Pologne) le et morte à Fontenay-aux-Roses (France) le, est une artiste ukrainienne de l'avant-garde.


History.

Sefrou was named for the Ahel Sefrou, a Berber tribe that once inhabited the area.  Sefrou's name might be brought from the berber name "Asfru" (ⴰⵙⴼⵔⵓ) which means "the solution" (in Morocco).  Sefrou was once home to one of the largest settlements of Moroccan Jews, the population estimated to have been as high as 8,000. The first Jewish people lived in the area of the Ahel Sefrou, most of whom were converted to Judaism around 2,000 years ago. In the 8th century, most of these were converted to Islam under Idris I of Morocco. In the 9th century, a second Jewish population settled from the Tafilalt area and Southern Algeria. Most of the descendants of these Jews stayed in Sefrou until 1967, when many moved to Israel.  Idris II of Morocco lived in Sefrou temporarily while overseeing the development of Fez.

Geography.

Sefrou is located at the edge of the Middle Atlas mountain range, and is southeast of Fez. Oued Aggai runs through the city, and about west of Sefrou are the Cascades, a small waterfall. Wadi Aggai also takes part in irrigation for the area. The Kef el-Moumen caves contain ancient tombs, one of which is claimed to be the tomb of Daniel. There is also a spring near Sefrou called Lalla Rekia, which is purported to cure insanity.

Culture.

Sefrou is known for its Sefrou Cherry Festival, which is UNESCO-endorsed, and is held annually every June. This festival, originally launched back in 1920, consists in a beauty contest in which Moroccan women would apply for the prestigious title of "Miss Cherry". The festival lasts for three days and includes folk music, Moroccan traditional cuisine, fantasia performances, and sporting events.  The town has a medina and two mosques, and every Thursday is market day.

Sefrou is a city in central Morocco situated in the Fès-Meknès region. It recorded a population of 79,887 in the 2014 Moroccan census, up from 63,872 in the 2004 census.

Séfrou (en arabe : ; en berbère: ⵚⴻⴼⵕⵓ) est une commune et ville — municipalité — du Maroc, chef-lieu de la province de Séfrou, dans la région de Fès-Meknès.


History.

First iteration of Sukarno.

Desirous of uniting the diverse archipelago of Indonesia into one state in 1945, the future President Sukarno promulgated Pancasila as the foundational philosophical theory of the new Indonesian state (in Indonesian "Dasar Negara"). His political philosophy was fundamentally an amalgamation of elements of monotheism, nationalism, and socialism. Sukarno consistently stated that Pancasila was a philosophy of Indonesian indigenous origin that he developed under the inspiration of Indonesian historical philosophical traditions, including indigenous Indonesian, Indian Hindu, Western Christian, and Arab Islamic traditions. "Ketuhanan" to him was originally indigenous, while "Kemanusiaan" was derived from the Hindu concept of Tat Tvam Asi, the Islamic concept of "fardhukifayah", and the Christian concept of neighborly love. Sukarno further explained that "Keadilan sosial", i.e. social justice, was derived from the Javanese concept of "Ratu Adil", i.e., the Just Leader, being a messianic Javanese ruler who would liberate that people from all kinds of oppression. Pancasila was intended to resolve contrasting Indonesian Muslim, nationalist, and Christian priorities.  The iteration of Pancasila that Sukarno presented on 1 June 1945 to the Investigating Committee for Preparatory Work for Independence ("Badan Penyelidik Usaha Persiapan Kemerdekaan" (BPUPK)) in a speech titled "The Birth of the Pancasila" originally defined the Pancasila thus:  1 June, since 2015, is a national public holiday to honour that address by Sukarno in which the basic principles of Pancasila were set.

Second iteration of the Founding Fathers.

Sukarno gave the first iteration of the Pancasila in his speech of 1 June 1945 to the Investigating Committee for Preparatory Work for Independence (BPUPK), and omitted the word "Indonesia". The Committee of Nine ("Panitia Sembilan"), composed of Sukarno, Mohammad Hatta, Mohammad Yamin, Alexander Andries Maramis, Ahmad Subardjo, Ki Hadikusumo, Wachid Hasyim, Agus Salim, and Abikusno, formulated the second iteration of the Pancasila for the Jakarta Charter and the Preamble of the Constitution of Indonesia of 1945 by reordering their original enumeration by Sukarno thus: the fifth "sila" of monotheism and religiosity was promoted as the first "sila"; the second "sila" remained, the original first "sila" was re-numbered as the third "sila", and the original third and fourth "sila" were re-numbered as the fourth and fifth "sila". Sukarno accepted this proposition of the other members. Further, the first "sila" of the Jakarta Charter and the Preamble of the Constitution of Indonesia of 1945, being the first of the original "sila" of Sukarno, was amended to read ""Ketuhanan dengan kewajiban menjalankan syariah Islam bagi pemeluk-pemeluknya"" ("Belief in Almighty God with the obligation for its Muslim adherents to carry out the Islamic law/Syari'ah"). On 18 August 1945 the PPKI amended it further by deleting "with the obligation for its Muslim adherents to carry out the Islamic law/Syari'ah" and therefore left the first "sila" as simply "Ketuhanan Yang Maha Esa".  The Constitution of Indonesia of 1945 defined the Pancasila as the fundamental principles of the independent Indonesian state.

Interpretation by the New Order administration.

The New Order administration of Suharto, the second President of Indonesia, strongly supported Pancasila. His government promoted the five principles as a key national ideology. They were outlined as representing the ancient wisdom of the Indonesian people, pre-dating the introduction of foreign religions such as Hinduism and Islam. In a July 1982 speech which reflected his attachment to Javanese beliefs, Suharto glorified Pancasila as a key to reach the perfect life ("ilmu kasampurnaning hurip") of harmony with God and fellow men.  After initially being careful not to offend the sensitivities of Muslim scholars who feared that the Pancasila might develop into a quasi religious cult, Suharto secured a parliamentary resolution in 1983 (Tap MPR No. 11/1983) that obligated all organizations in Indonesia to adhere to Pancasila. He also instituted a mandatory program to indoctrinate all Indonesians, from primary school students to office workers, in the Pancasila, which program was denominated "Penataran P4". In practice, however, the administration of Suharto exploited the vagueness of the Pancasila to justify its acts and to condemn opponents as "anti-Pancasila".

Rationale.

The formulation of Pancasila took place in the mid-20th century immediately after the end of the Second World War. Thus, the ideology reflects the socio-political conditions of the late colonial period in Indonesia and the ensuing war. Its concept derived and synthesized from the ideas and ideals of Indonesia's founding fathers, most prominently Sukarno's. The historical period that most influenced Indonesia's founding fathers was the socio-political conditions of the Dutch East Indies in the early and mid 20th century.  By the first half of the 20th century, some ideologies that had been established or made their way to the Dutch East Indies included imperialism and its antithesis anti-colonial nationalism, traditional Javanese statecraft, Islamism, democracy, socialism, and communism. Proponents of these ideologies had formed political organizations or parties to forward their respective causes. The Islamist party Sarekat Islam was established in 1905 followed by Masyumi in 1943. The Communist Party was established in 1914, while Sukarno's nationalist Indonesian National Party was established in 1927. Favouring one ideology over another would not satisfy the whole spectrum of Indonesian people, thus it was decided that the new republic need to synthesize a new ideology derived from indigenous Indonesian values as well as common shared values derived from various ideologies.

Pluralism and inclusiveness.

Indonesia is a multicultural nation, a diverse country composed of various ethnic groups with different languages, cultures, religions, and ways of life. The founding fathers had decided that the state ideology should encompass and shelter the whole spectrum of Indonesian society, in which a consensus for common good must be strived for and justice is served. As the result, Pancasila is often viewed as a form of pluralism and moderation, a potpourri of different ideologies, ranging from the socialist to nationalist and religious.  Some compromises were made during the formation of Pancasila to satisfy certain elements of Indonesian society. For example, despite its overwhelming Muslim population, Indonesia did not adopt political Islam nor proclaim Islam as its official religion. Other than Islam, Indonesia only recognizes the following world religions:  The adoption of Indonesian instead of Javanese as the national language had practical value as a lingua franca and reduced concerns about favoring the Javanese majority.  Pancasila was influenced by certain aspects of selected world values and ideologies, such as nationalism, humanitarianism, democracy, socialism, and religiosity. The need to unify this diverse country also led to the formulation of the national motto, Bhinneka Tunggal Ika, which can be translated as unity in diversity. It declares the essential unity of its members despite ethnic, regional, social, or religious differences.

Moderation and tolerance.

In 1945, during the formation of Pancasila, there was much debate between nationalists who called for a pluralistic state and Islamists who wanted a religious state ruled by Islamic law or sharia. The nation's founders chose religious tolerance. Pancasila encourage its proponent to practice moderation and toleration, thus radicalism and extremism are discouraged. In order to live harmoniously in a pluralistic Indonesian society, one's membership in a religious, ethnic, or social group should not dominate, discriminate, or be prejudiced in their relations with other groups.

Criticism.

The International Humanist and Ethical Union (IHEU) has criticized the first "sila" because it does not define a right to atheism, i.e., a rejection of theistic belief, and enables a culture of repression against atheists. The IHEU argued that as long as Indonesian law only recognized the religions of Buddhism, Confucianism, Hinduism, Islam, Protestantism, and the Roman Catholic Church, persons who did not identify with any of them, including atheists, would "continue to experience official discrimination." Followers of other religions, in particular Judaism, also face discrimination as they are not officially recognized by the government. Jewish Indonesians often have no choice but to state their religion as Christian on their government issued ID cards.

Pancasila () is the official, foundational philosophical theory of Indonesia. Pancasila comprises two Old Javanese words originally derived from Sanskrit: ""pañca"" ("five") and ""sīla"" ("principles"). Thus it is composed of five principles and contends that they are inseparable and interrelated:

Le Pancasila (prononcer ) est la philosophie de l'État indonésien. Ce nom est formé à partir des mots sanskrit "panca", "cinq", et "sila" "principe" ou "précepte". Il a été repris à celui des cinq préceptes du bouddhisme (ne pas tuer, ne pas voler, ne pas mal se conduire sexuellement, ne pas mentir, ne pas se droguer).


History.

DDR2 SDRAM was first produced by Samsung in 2001. In 2003, the JEDEC standards organization presented Samsung with its Technical Recognition Award for the company's efforts in developing and standardizing DDR2.  DDR2 was officially introduced in the second quarter of 2003 at two initial clock rates: 200 MHz (referred to as PC2-3200) and 266 MHz (PC2-4200). Both performed worse than the original DDR specification due to higher latency, which made total access times longer. However, the original DDR technology tops out at a clock rate around 200 MHz (400 MT/s). Higher performance DDR chips exist, but JEDEC has stated that they will not be standardized. These chips are mostly standard DDR chips that have been tested and rated to be capable of operation at higher clock rates by the manufacturer. Such chips draw significantly more power than slower-clocked chips, but usually offered little or no improvement in real-world performance. DDR2 started to become competitive against the older DDR standard by the end of 2004, as modules with lower latencies became available.

Specification.

Overview.

The key difference between DDR2 and DDR SDRAM is the increase in prefetch length. In DDR SDRAM, the prefetch length was two bits for every bit in a word; whereas it is four bits in DDR2 SDRAM. During an access, four bits were read or written to or from a four-bit-deep prefetch queue. This queue received or transmitted its data over the data bus in two data bus clock cycles (each clock cycle transferred two bits of data. Increasing the prefetch length allowed DDR2 SDRAM to double the rate at which data could be transferred over the data bus without a corresponding doubling in the rate at which the DRAM array could be accessed. DDR2 SDRAM was designed with such a scheme to avoid an excessive increase in power consumption.  DDR2's bus frequency is boosted by electrical interface improvements, on-die termination, prefetch buffers and off-chip drivers. However, latency is greatly increased as a trade-off. The DDR2 prefetch buffer is four bits deep, whereas it is two bits deep for DDR. While DDR SDRAM has typical read latencies of between two and three bus cycles, DDR2 may have read latencies between three and nine cycles, although the typical range is between four and six. Thus, DDR2 memory must be operated at twice the data rate to achieve the same latency.  Another cost of the increased bandwidth is the requirement that the chips are packaged in a more expensive and difficult to assemble BGA package as compared to the TSSOP package of the previous memory generations such as DDR SDRAM and SDR SDRAM. This packaging change was necessary to maintain signal integrity at higher bus speeds.  Power savings are achieved primarily due to an improved manufacturing process through die shrinkage, resulting in a drop in operating voltage (1.8 V compared to DDR's 2.5 V). The lower memory clock frequency may also enable power reductions in applications that do not require the highest available data rates.  According to JEDEC the maximum recommended voltage is 1.9 volts and should be considered the absolute maximum when memory stability is an issue (such as in servers or other mission critical devices). In addition, JEDEC states that memory modules must withstand up to 2.3 volts before incurring permanent damage (although they may not actually function correctly at that level).

Chips and modules.

For use in computers, DDR2 SDRAM is supplied in DIMMs with 240 pins and a single locating notch. Laptop DDR2 SO-DIMMs have 200 pins and often come identified by an additional S in their designation. DIMMs are identified by their peak transfer capacity (often called bandwidth).  <nowiki>*</nowiki> "Some manufacturers label their DDR2 modules as PC2-4300, PC2-5400 or PC2-8600 instead of the respective names suggested by JEDEC. At least one manufacturer has reported this reflects successful testing at a higher-than-standard data rate whilst others simply round up for the name."  Note: DDR2-xxx denotes data transfer rate, and describes raw DDR chips, whereas PC2-xxxx denotes theoretical bandwidth (with the last two digits truncated), and is used to describe assembled DIMMs. Bandwidth is calculated by taking transfers per second and multiplying by eight. This is because DDR2 memory modules transfer data on a bus that is 64 data bits wide, and since a byte comprises 8 bits, this equates to 8 bytes of data per transfer. In addition to bandwidth and capacity variants, modules can:  Note:

Backward compatibility.

DDR2 DIMMs are not backward compatible with DDR DIMMs. The notch on DDR2 DIMMs is in a different position from DDR DIMMs, and the pin density is higher than DDR DIMMs in desktops. DDR2 is a 240-pin module, DDR is a 184-pin module. Notebooks have 200-pin SO-DIMMs for DDR and DDR2; however, the notch on DDR2 modules is in a slightly different position than on DDR modules.  Higher-speed DDR2 DIMMs can be mixed with lower-speed DDR2 DIMMs, although the memory controller will operate all DIMMs at same speed as the lowest-speed DIMM present.

Relation to GDDR memory.

GDDR2, a form of GDDR SDRAM, was developed by Samsung and introduced in July 2002. The first commercial product to claim using the "DDR2" technology was the Nvidia GeForce FX 5800 graphics card. However, it is important to note that this GDDR2 memory used on graphics cards is not DDR2 per se, but rather an early midpoint between DDR and DDR2 technologies. Using "DDR2" to refer to GDDR2 is a colloquial misnomer. In particular, the performance-enhancing doubling of the I/O clock rate is missing. It had severe overheating issues due to the nominal DDR voltages. ATI has since designed the GDDR technology further into GDDR3, which is based on DDR2 SDRAM, though with several additions suited for graphics cards.  GDDR3 and GDDR5 is now commonly used in modern graphics cards and some tablet PCs. However, further confusion has been added to the mix with the appearance of budget and mid-range graphics cards which claim to use "GDDR2". These cards actually use standard DDR2 chips designed for use as main system memory although operating with higher latencies to achieve higher clockrates. These chips cannot achieve the clock rates of GDDR3 but are inexpensive and fast enough to be used as memory on mid-range cards.

Further reading.

Note**: JEDEC website requires registration ($2,500 membership) for viewing or downloading of these documents: http://www.jedec.org/standards-documents

Double Data Rate 2 Synchronous Dynamic Random-Access Memory, officially abbreviated as DDR2 SDRAM, is a double data rate synchronous dynamic random-access memory interface. It superseded the original DDR SDRAM specification, and is superseded by DDR3 SDRAM (launched in 2007). DDR2 DIMMs are neither forward compatible with DDR3 nor backward compatible with DDR.

La DDR2 SDRAM ou DDR2 (de l'anglais ") est la seconde génération de mémoire vive de type DDR pour les ordinateurs personnels, la première étant la technologie DDR SDRAM. Ce type de mémoire informatique utilise des circuits intégrés. Cette technologie fait partie de la famille des mémoires vives SDRAM, qui elle-même est une des multiples versions des mémoires DRAM. DDR2 respecte en outre le format DIMM.


Description.

Fibropapillomatosis is a benign tumour disease of marine turtles, predominantly in the green sea turtle, "Chelonia mydas", but it has also been reported in the loggerhead sea turtle "Caretta caretta", olive ridley "Lepidochelys olivacea", Kemp's ridley "Lepidochelys kempii", and leatherbacks "Dermochelys coriacea". This neoplastic disease causes proliferation of papillary cells (hyperplasia) and gives rise to excess fibrous connective tissue in both epidermal and dermal skin layers – or more specifically, proliferation of dermal fibroblasts and epidermal keratinocytes. This causes tumorigenesis in sizes less than 1 cm up to more than 30 cm in diameter. FP is most often found externally around the armpits, genitals, neck, eyes, and tails of turtles, but also occur in and around the mouth, and rarely in internal organs or on the carapace. This, in turn, impedes vision, feeding, and movement. Around 25–30% of turtles with external tumours also have internal tumours, primarily in heart, lungs and kidneys.  FP incidence is highest among immature and juvenile green turtles, while it is rare in adults. The suggestions for this pattern include the tumours can regress and be cured, which has been documented in some individuals, even when tumours were severe. However, the responses that cause these tumour regressions is unknown. Secondly, the juvenile individuals with FP might die before reaching adulthood.

Prognosis.

The tumours appear to be benign and can be present for many years, but if large, can mechanically hamper sight, swallowing, and swimming, which may ultimately be fatal. While external tumours hamper movement and sight, internal tumours interfere with system functioning, another potentially fatal factor. As the tumours progress, individuals with large numbers of tumours may become anaemic, have a lack of proteins and iron, and in more advanced stages even suffer from acidosis caused by imbalanced calcium/phosphorus ratios and severe emaciation.

Other species.

Fibropapillomas are present in other animal groups, but are caused by different viruses, for example the bovine papillomavirus.

History.

The first documented case of the disease was in 1938 in Key West, Florida. Long-term studies found no signs of the disease on Florida's Atlantic coast in the 1970s, but during the 1980s FP was recorded in incidences varying from 28–67%. Today, incidences as high as 92% have been reported in Kaneohe Bay, Oahu, Hawaii. Generally, FP is most prominent in warmer climates. Recent research has found that FP is caused by stress and tumours have been observed in turtles that are part of turtle tourism tours. It is thought that the presence of tourists causes the turtles stress

Cause.

The FP is an infectious disease with horizontal transmission. An alphaherpesvirus initially called fibropapilloma-associated turtle herpesvirus (FPTHV), and now called "Chelonid alphaherpesvirus 5", is believed to be the causative agent of the disease. The reason for this belief is because nearly all tissue samples tested from turtles with lesions carry genetic material of this herpesvirus, varying between 95 and 100% depending on different studies and locations. The DNA loads of the herpesvirus in tumour tissue are 2.5–4.5 logarithms higher than in uninfected tissue. The FPTHV herpesvirus has been found in turtles free from FP and this suggest that the FP progression is multifactorial and might even involve some sort of tumour-promoting phase. The global prevalence of the disease also suggests a multifactorial cause, rather than single factors or agents. Possible factors include some parasites, bacteria, environmental pollutants, UV-light, changing water temperatures and biotoxins. Even physiological factors such as stress and immunologic status appear to be associated with FP.  The leech genus "Ozobranchus" is thought to be the mechanical vector of the herpesvirus, transmitting the virus from one turtle to another. These leeches are common turtle ectoparasites that exclusively feed on turtle blood, and some leeches have been found carrying more than 10 million copies of the herpesvirus DNA. The green sea turtle is an herbivore and feeds primarily on seagrass and macroalgae. Two toxins which are suspected to be associated with FP are found epiphytically on these plants. First, the toxic compound lyngbyatoxin from the cyanobacterium Lyngbya majuscule, and second the toxin okadaic acid – a documented tumour-promoting toxin - from the dinoflagellate "Prorocentrum". Again, causality has not been concluded, but an association seems to exist between the distribution of especially the dinoflagellates and the occurrence of FP, and as they are found on weeds, they can be ingested by foraging green sea turtles. Turtles with FP are found to have a compromised immune system. They have higher phagocytic leucocyte counts (especially heterophils) compared to healthy individuals, which seems to be an effect of FP, as it is mostly evident in individuals with severe tumours. This further supports the hypothesis of the herpesvirus as a causative agent. Immunosuppression is strongly correlated with FP, but does seem to be a consequence of the development and growth of FP rather than a prerequisite, which is similar to other virus-induced tumour diseases in other species, such as Marek's disease in poultry.

Treatment.

Surgical removal of tumors caused by FP is the most common treatment method. Photodynamic therapy and electrochemotherapy are also used, as is CO laser surgery.

Epidemiology.

FP affects green sea turtle populations all over the world, making it a panzootic. It is especially found in warmer climates, such as the Caribbean, Hawaii, Japan, and Australia, where up to 70% of individuals in a population have FP.  Epidemiological links are seen between FP rates, nitrogen footprints, and invasive macroalgae. The strongest association with FP is with habitat type, especially increased anthropogenic activity causing high-nitrogen footprints in a surrounding environment where green sea turtles are found. Sea turtles do live in very complex ecosystems, with both near-shore habitats and several years in the open ocean, which makes study of ecosystem associations difficult. Even so, observations support the hypothesis that near-shore habitats have a strong correlation with the disease, as newly recruited individuals from the pelagic life phase have never been found with tumours, and when migrating to more shallow ocean zones, such as the neritic zone, individuals still remain free from FP, but when entering lagoon systems, turtles may become infected. The high prevalence of FP is also associated with habitats’ poor quality, while FP is absent in some habitats of good quality.  Turtles are known to be robust to physical damage, but are surprisingly very susceptible to biological and chemical contaminants caused by anthropogenic activity. As the turtles forage on invasive macroalgae in nutrient-rich waters, they can ingest environmental nitrogen in the form of arginine, which is known to regulate immune activity, promote herpesviruses, and contribute to tumorigenesis.

Turtle fibropapillomatosis (FP) is a disease of sea turtles. The condition is characterized by benign but ultimately debilitating epithelial tumours on the surface of biological tissues. FP exists all over the world, but it is most prominent in warmer climates, affecting up to 50–70% of some populations.

La fibropapillomatose (FP) est une maladie de peau qui touche les tortues marines. Elle serait occasionnée par un virus, le, qui pourrait être du type herpès.


Early life.

Camacho was born in the village of Hagåtña, Guam to Felix Martinez Camacho (1893–1975) and Antonia Cruz Garcia (1893–1985), both Spanish immigrants. His siblings included Maria Josefina Tanaka, Juan Camacho, Luis Camacho and Eddie Camacho. From 1946 to 1949, he attended Aquinas College in Grand Rapids, Michigan. In 1952, he earned a D.D.S. degree from Marquette University in Milwaukee, Wisconsin.

Political career.

In the 1974 gubernatorial election, he was defeated for reelection in a re-match senator Ricardo Bordallo won the election. An election challenge by the Bordallo/Sablan campaign went all the way to the U.S. Supreme Court. Following his unsuccessful bid for reelection as governor, Camacho resumed his career as a dentist.

Governor of Guam (1969–1975).

At the young age of forty-four, Camacho succeeded Governor Manuel F.L. Guerrero as governor of Guam, with Kurt Moylan appointed as lieutenant governor. Camacho's term as appointed governor lasted only eighteen months, due to the Elective Governor Act that was signed into law by the U.S. Congress in 1968, allowing for Guam's citizens to choose their governor. The act took effect in 1970, when Guam's first election was held. Camacho's term was best remembered for his Christmas 1969 visit to the troops from Guam who were fighting in Vietnam.

Camacho-Salas Campaign.

Camacho first selected senator G. Ricardo Salas as his lieutenant governor running mate, but Salas was subsequently replaced by Kurt Moylan.

Camacho-Moylan Campaign.

Camacho was a candidate in Guam's first election for governor with Kurt Moylan running for lieutenant governor. The two running mates are Republican primary, while the Democratic primary was closely between former governor Manuel F. L. Guerrero, Senator Ricardo Bordallo and attorney and former speaker Joaquin C. "Kin" Arriola. After they close the primary and a contentious runoff election which is Bordallo who is defeated by Guerrero, and the general election as Camacho/Moylan defeated by Bordallo/Taitano.  Camacho and Moylan's historic inauguration was held on January 4, 1971 at the Plaza de España in Agana. He uses the resources of the government to enhance economic opportunities by granting incentives through the Guam Economics Development and offering various forms of assistance to the private sector. During his entire five and a half years in office, Camacho presided over one of the largest eras of hotel construction activities on Guam, with construction finishing or starting on the Kakue Hotel, Reef Hotel, Hilton Hotel, Okura Hotel, Fujita Tumon Beach, Continental Travelodge, and Guam Dai Ichi Hotel.  Camacho also initiated massive road projects that were continued by his successors, including the widening of Marine Drive (now Marine Corps Drive) from Hospital Road north to Route 16 in Harmon, and the reconstruction of other major highways in the villages of Agat, Dededo and Tamuning, among others.  He is also credited with enticing many educated Chamorros back to Guam, to reverse what was seen as a “brain drain” at the time, including Tony Palomo, Greg Sanchez, Mary Sanchez, Tony Unpingco, Dr. Pedro Sanchez, Dr. Katherine Aguon, Juan C. Tenorio, Bert Unpingco, Ben Perez, Eddie Duenas, Joseph F. Ada and Frank Blas. Many of them took jobs with the government of Guam as administrators and later became senators. Camacho also kept on other able administrators even if they were not of his party affiliation which served to stabilize the government.  As a team, Camacho and Moylan worked to develop economic opportunity by creating incentives to attract business and encourage local participation in business. At the time Guam elected its first governor the federal government still had control over much of the island's utilities and roads. They struggled to work toward gaining more self-government and self-determination.

Personal life.

Camacho was married to Lourdes Duenas Perez, and had seven children, including former Governor of Guam, Felix Perez Camacho, Carlos, Thomas, Ricardo, Francis, Victor, and his only daughter Mary Camacho Torres is now a senator from the Guam Legislature, she is married to Supreme Court of Guam Chief Justice Robert J. Torres, Jr. Originally appointed in 1969, he became Guam's first elected governor the following year and served in that capacity until August 1975.

Later years.

Following his defeat, Camacho returned to his career as a dentist, continuing in private practice until his death on December 6, 1979 four years later, at the age of 55. He is now buried at the Pigo Cemetery in Anigua.

Carlos Garcia Camacho (November 16, 1924 – December 6, 1979) was a Guamanian politician and member of the Republican Party. He served as the last appointed Governor of Guam from 1969 to 1971 and the first elected Governor of Guam from 1971 to 1975. He was the father of Felix Camacho, a former senator in the Guam Legislature, and also served as Governor of Guam.

Carlos Camacho, né le à Hagåtña et mort le à Tamuning, est un homme politique américain. Membre du Parti républicain, il le gouverneur élu de Guam du au.


History.

Originally known as "La Pointe-des-Chênes", which roughly translates to "The Point of the Oak Trees", Ste. Anne was the first parish established in the area, dating back to 1856, when the territory was a part of Rupert's Land. The early settlers, French-speaking Habitants from Canada East, arrived looking for farmland. The first 198 families in the community busied themselves with their first major industry, supplying lumber for the construction of the St. Boniface Cathedral. The Hudson's Bay Company also had a strong presence in the community in the 1800s. Ste. Anne served as a stopover for weary travelers on their journey to Winnipeg, along the famed Dawson Trail.  In June 1959, Ste. Anne experienced the worst flood in its history. Water rose at a rate visible by eye, and the Ste. Anne Hospital was evacuated. In 1960, the Seine River diversion project was completed to prevent future floods.

Geography and climate.

Ste. Anne is situated just east of the longitudinal centre of Canada (near the geographical centre of North America), and approximately north of the border with the United States. It is near the eastern edge of the Canadian Prairies. It is surrounded by rich agricultural land to the west, and the boreal forest to the east. The Seine River runs through the middle of town. The tree-lined river is very picturesque and gives the area a beautiful naturalist look. The closest urban area with over 500,000 people is Winnipeg, approximately west of Ste. Anne.  Ste. Anne has an extreme continental climate (Köppen climate classification Dfb). Ste Anne is approximately northwest of International Falls, Minnesota, which according to USA Today is the coldest place in the continental USA. Summers are short and cool, with only three months (June to August) when the average high temperature exceeds 20 °C (68 °F). Even during the summer months, evening and night temperatures are quite cool, for example the average low in July is 13 °C (55 °F). Spring and autumn are highly variable seasons, but generally very cool. On average there are only 110 frost-free days per year. Winters are best described as extremely long and bitterly cold, with snow cover generally from November to March. According to Environment Canada, the daily average high temperatures range from -13 °C (9 °F) to 26 °C (79 °F), and average low temperatures range from -23 °C (-9 °F) to 13 °C (55 °F). The weather is characterized by an abundance of sunshine throughout the year. July is the sunniest month, and November the least sunny.

Infrastructure and public services.

Transportation.

Ste. Anne is located from Winnipeg. This distance is covered by a four-lane divided highway (Highway 12 and the Trans-Canada Highway). Highway 12 connects Ste. Anne with the United States border, as well as the Trans-Canada Highway. Two secondary roads, Provincial Roads 207 and 210 pass through town as Avenue Centrale Avenue. PR 207 is a part of the Old Dawson Trail, one of the earliest roads that linked Manitoba with Northwestern Ontario.  Winnipeg's James Armstrong Richardson International Airport is, or less than a one-hour drive, from Ste. Anne.

Economic base.

The largest employers in Ste. Anne are in the health and education services sector. The town boasts a senior's care home that houses 150 residents. The Ste. Anne Hospital serves the town and the surrounding area, and provides emergency medical services 24-hours a day. A medical clinic in the town also has ten doctors on staff, and an onsite pharmacy. The Seine River School Division #14 has its administration building in Ste. Anne. Most other businesses in Ste. Anne provide retail goods and services to the town's residents and those in the surrounding community.

Education.

Ste. Anne has four schools: Ste. Anne Elementary (English, K to grade 8), Ste. Anne Immersion (French immersion, K to grade 8) opened in 1994, Ste. Anne Collegiate (English, Grade 9 to 12), and Ecole Pointe-des-Chênes (French, K to grade 12). French immersion students wishing to continue in French immersion usually attend Collège Lorette Collegiate, approximately 20 kilometres west of Ste. Anne.

Health care.

Ste. Anne Hospital was opened in 1954. The hospital is currently a 21-bed, acute-care facility serving the residents of Ste. Anne and the region. Recent investments in Ste. Anne Hospital include a $1.5-million project for safety and security upgrades including the relocation of the nursing station and the creation of two new birthing rooms. In October 2007, the Health Minister of Manitoba announced that more than $6 million will be invested in renovations to the Ste. Anne Hospital to increase the number of surgical suites and establish a post-anesthetic care unit. Renovations are scheduled to be completed by 2010.  For senior citizens, Ste. Anne has the Villa Youville, which combines a personal care home with an 85-suite seniors housing complex. The francophone facility is located in a park-like setting on the banks of the Seine River.  The Centre Medicale Seine has a staff of doctors and a lab. A pharmacy is also located within the clinic. Seine River Dental Centre is located across the street from the medical centre.

Housing.

Homes in Ste. Anne range from mobile homes to houses. Ste. Anne also has apartment buildings, including a 28-unit apartment project for those with lower-incomes and those with mental health-care needs. The project, led by the Ste. Anne Knights of Columbus Council, was supported by funding from the Canada-Manitoba Affordable Housing Initiative, and by land donated by the town.

Churches.

Ste. Anne has two churches. The Ste. Anne Catholic Church (opened in 1898) is a town landmark. Masses are held in French and English. The church interior was completely renovated in 2007. Ste. Anne also has the Dayspring Fellowship Church, with services in English.

Services.

Ste. Anne has a public library constructed from a donated residence, whose character is still evident in the architecture of the building (the children's section used to be a kitchen).  The town has a volunteer fire department that serves the surrounding municipality and the municipality of Taché. The municipality of Taché also helps out Ste. Anne when it needs aid.  The town has its own police force.

Attractions.

Festivals.

Ste. Anne plays host to Dawson Trail Days held during the September long weekend. It is a celebration of the area's heritage and the history of the Dawson trail. Many activities are planned each year, and the event serves as a windup for local residents after an enjoyable summer.

Outdoor activities.

Ste. Anne features a splash pad that opened in 2016 in the Parc des Redemptoristes, a skateboard park that opened in 2016 on Arena Road, and numerous soccer and baseball fields.  The Parc des Redemptoristes is situated beside the Seine River in the center of town.

Sports.

Ice hockey and curling are the favorite sports in Ste. Anne. The town has an ice-skating arena and curling rink. The Ste. Anne Aces, an ice hockey team, play in the Carillon Senior Hockey League. Soccer and Baseball are also popular and growing sports in this town.  In March 2009, three natives of Ste. Anne competed in the NCAA Women's Frozen Four. Known colloquially as the Ste. Anne Three, Bailey Bram, representing the Mercyhurst Lakers women's ice hockey program, Jocelyne Larocque of the Minnesota–Duluth Bulldogs women's ice hockey program, and Melanie Gagnon, senior captain of the Minnesota Golden Gophers women's ice hockey program, competed in the event.

Town Council members.

The Mayor of Ste. Anne is Richard Pelletier. Other members include Councillors Ginette Gagnon, Tiana Bohemier, Yvan St. Vincent, Lyle Davies, and Chief Administrative Officer, Marc Darker.

Ste. Anne, or "Sainte-Anne-des-Chênes", is a town in Manitoba, located about 42 km southeast of Winnipeg. The population was 2,114 in 2016, 1,524 in 2011, and 1,513 in 2011. It is known for being located on the Seine River and at the heart of the Old Dawson Trail. The town is surrounded by the Rural Municipality of Ste. Anne.

Sainte-Anne (en anglais : "Ste. Anne") ou Sainte-Anne-des-Chênes est une ville du Manitoba située à 40 km à l'est de Winnipeg.


The Veronica.

Belief in the existence of authentic images of Christ is connected with the old legend of Abgar of Edessa, regarding the "Mandylion", and the apocryphal writing known as the "Mors Pilati", Acts of Pilate, regarding the "veil of Veronica". The oldest and best known of these images was called the "vera icon" (true image), which in ordinary language became known as "veronica".  According to tradition Veronica encountered Jesus along the Via Dolorosa on the way to Calvary. When she paused to wipe the blood and sweat off his face with her veil, his image was imprinted on the cloth. The story is not recorded in its present form until the Middle Ages. The event is commemorated by the Sixth Station of the Cross.

Marie of St Peter Eluere.

In 1844, Sister Marie of St Peter, a Carmelite nun in Tours, France, reported an interior locution in which Jesus told her, ""Those who will contemplate the wounds on My Face here on earth, shall contemplate it radiant in heaven."" She later reported further "communications", as she termed them, with Jesus and the Virgin Mary in which she was urged to spread the devotion to the Holy Face of Jesus, in reparation for the many insults Jesus suffered in his Passion. Devotion to the Holy Face of Jesus started to spread among Roman Catholics in France.

Leo Dupont.

Leo Dupont was a religious man from a noble family who had moved to Tours. In 1849 he had started the nightly Eucharistic Adoration movement in Tours, from where it spread within France. He later came to be known as the "Holy Man of Tours". Upon hearing of Sister Marie of St Peter’s reported visions, he started to burn a vigil lamp continuously before a picture of the Holy Face of Jesus, at that time, an image based on the Veil of Veronica.  Dupont prayed for and promoted the case for a devotion to the Holy Face of Jesus for around 30 years. But the documents pertaining to the life of sister Marie of St. Peter and the devotion were kept by the Church and not released. Yet Dupont persisted. Eventually, in 1874 Charles-Théodore Colet was appointed as the new Archbishop of Tours. Archbishop Colet examined the documents and in 1876 gave permission for them to be published and the devotion encouraged, shortly before Dupont died. Dupont was thereafter at times referred to as the Apostle of the Holy Face.  When Leo Dupont died in 1876, his house on Rue St. Etienne in Tours was purchased by the Archdiocese of Tours and turned into the Oratory of the Holy Face. The oratory is administered by an order of priests called the Priests of the Holy Face, canonically erected in 1876. The Devotion to the Holy Face of Jesus was approved by Pope Leo XIII in 1885, who expressed a desire to establish a similar oratory in Rome. This was eventually opened in the Via Pietro Cavallini in 1891 and administered by the Priests, but was demolished in subsequent redevelopment.

Thérèse of Lisieux.

Thérèse of Lisieux was a French nun who received the Carmelite habit in 1889 and later became known by the religious name "St. Thérèse of the Child Jesus and of the Holy Face". She was introduced to the Holy Face devotion through her blood sister Pauline, Sister Agnès of Jesus. Thérèse wrote many prayers to express the devotion to the Holy Face. She wrote the words "Make me resemble you, Jesus!" on a small card and attached a stamp of the Holy Face to it. She pinned the prayer in a small container over her heart since at that time the Holy Face Medal did not exist. In August 1895, in her "Canticle to the Holy Face" she wrote: "Jesus, Your ineffable image is the star which guides my steps. Ah, You know, Your sweet Face is for me Heaven on earth. My love discovers the charms of Your Face adorned with tears. I smile through my own tears when I contemplate Your sorrows."  Thérèse also composed the "Holy Face prayer for sinners": "Eternal Father, since Thou hast given me for my inheritance the adorable Face of Thy Divine Son, I offer that face to Thee and I beg Thee, in exchange for this coin of infinite value, to forget the ingratitude of souls dedicated to Thee and to pardon all poor sinners.

Shroud of Turin.

A broader devotion to the Holy Face is based on the image used on the Shroud of Turin which some believe to be the burial cloth of Jesus. It is different from the likeness of Jesus on the Veil of Veronica, although the veil image had earlier been used in devotions. Since the Holy Face image is said to have been obtained from the burial cloth of Jesus, it is assumed to be a post-crucifixion image. However, the likeness on the Veil of Veronica is by definition pre-crucifixion, for it is assumed to have been imprinted when Veronica encountered Jesus in Jerusalem along the Via Dolorosa on the way to Calvary.  Although the Shroud of Turin has been publicly displayed by Roman Catholics at least since the 16th century, the faint image of the Holy Face on it can not be clearly seen with the naked eye and was only observed with the advent of photography. In 1898, amateur Italian photographer Secondo Pia was startled by the negative of the image in his darkroom as he was developing the first photograph of the shroud. The happenstance by which Secondo Pia received the King’s approval to attempt the first photograph of the Shroud for an exhibition was unusual in its own right. And Pia later said that on the evening of May 28, 1898 he almost dropped and broke the photographic plate in the darkroom from the shock of seeing the image of a face on the Shroud (for the first time ever) that could not have been clearly observed with the naked eye.  Hence devotions to the Holy Face prior to that year relied on earlier images, based on paintings of the Veil of Veronica.

Maria Pierina De Micheli.

On the first Friday in Lent 1936, Sister Maria Pierina De Micheli, who was born near Milan Italy, reported a vision in which Jesus told her: "“I will that My Face, which reflects the intimate pains of My Spirit, the suffering and the love of My Heart, be more honored. He who meditates upon Me, consoles Me”".  Further reported visions of Jesus and Mary urged Sister Maria Pierina to make a medal with the Holy Face of Jesus. This became known as the Holy Face Medal. On one side the medal bears a replica of the Holy Face image from Shroud of Turin and an inscription based on Psalm 66:2: "Illumina, Domine, vultum tuum super nos", i.e. ""May, O Lord, the light of Thy countenance shine upon us"". On the other side of the medal, there is an image of a radiant Sacred Host, the monogram of the Holy Name ("IHS"), and the inscription "Mane nobiscum, Domine" i.e. ""Stay with us, O Lord"".  In another vision, Sister Maria Pierina reported that Jesus told her: "“Every time my Face is contemplated I will pour out my love into the heart of those persons, and by means of my Holy Face the salvation of many souls will be obtained”". She further reported that Jesus wanted a special Feast on the day before Ash Wednesday in honor of His Holy Face, to be preceded by a Novena (9 days) of prayers.  After some effort Sister Maria Pierina managed to obtain permission to cast the medal and its use started to grow in Italy. As World War II started, many soldiers and sailors were given a Holy Face Medal as a means of protection. Sister Maria Pierina herself died in 1945 at the end of the war.  In 2000 Pope John Paul II stated that inscription "Illumina, Domine, Vultum tuum super nos" on the Holy Face Medal underscores the need for deeper reflection on the Face of Jesus and the spread of devotion to it.

Vatican approval and Feast Day.

The first medal of the Holy Face was offered to Pope Pius XII who approved the devotion and the medal. In 1958, he formally declared the Feast of the Holy Face of Jesus as Shrove Tuesday (the Tuesday before Ash Wednesday) for all Roman Catholics.  On the occasion of the 100th year of Secondo Pia's (May 28, 1898) first photograph of the Shroud of Turin, on Sunday May 24, 1998 Pope John Paul II visited the Turin Cathedral. In his address on that day, he said:""the Shroud is an image of God's love as well as of human sin"" and ""it is an icon of the suffering of the innocent in every age"."  The Holy Face devotion and the Holy Face Medal spread among Roman Catholics worldwide, with organizations such as the Holy Face Association.

Theological analysis.

In his 2005 book "On the Way to Jesus Christ", Pope Benedict XVI performed an analysis of Holy Face devotions, and characterized them as having three separate components. The first element is discipleship, and the orientation of one's life towards an encounter with Jesus. The second element is seeing Jesus in the Eucharist. The third element is eschatological, and is interwoven between the other two.  Referring to Benedict XVI stated that the first element (i.e. discipleship) involves seeing Jesus in the face of the poor and the oppressed, and caring for them, but to properly see Jesus in the face of those in need, believers first need to become better acquainted with Jesus through the Eucharist. The second element involves relating the Passion of Jesus, and the suffering expressed by the images that represent his wounded face to the Eucharistic experience. Thus the devotion that starts with the images of the face of Jesus leads to his contemplation in the Eucharistic experience. The eschatological element then builds on awakening to Christ by contemplating his face in the Eucharist.

Institute for Holy Face research.

The "International Institute for Research on the Face of Christ" was formed in 1997 by Cardinal Fiorenzo Angelini and the Benedictine Sisters of the Reparation of the Holy Face in Rome.  In his message to the 6th annual conference of the Institute held in Rome in October 2002, Pope John Paul II emphasized the spiritual importance of contemplation of the Face of Christ and referred to his Apostolic Letter "Novo Millennio Ineunte" which stated:  In the same message John Paul II also related the theme of the contemplation to that of contemplating the Person of Christ as discussed in his first encyclical "Redemptor hominis".

The Holy Face of Jesus is a title for specific images which some Catholics believe to be miraculously-formed representations of the face of Jesus Christ. The image obtained from the Shroud of Turin is associated with a specific medal worn by some Roman Catholics and is also one of the Catholic Devotions to Christ.

La Sainte Face ou Sainte Face de Jésus correspond à des formules iconographiques relevant de reliques et de légendes différentes qui convergent vers l'idée du Logos incarné dont l'empreinte du visage du Christ serait la preuve. Selon la tradition chrétienne, ce visage aurait été miraculeusement imprimé sur tissu et ferait partie des icônes acheiropoiètes mais il a pu être également réalisé par des artistes selon une fidélité plus ou moins grande au modèle.


Design and development.

Hans Klemm's first light aircraft was the Daimler L15 and the L20 had much in common with it. Both were cantilever monoplanes with twin open, tandem cockpits and engines of very low power. The L20's low wing distinguished it from its predecessor and had the advantage of providing a low centre of gravity and better view during the landing approach as well as better protection for occupants in case of crash landings. The low-set wing also allowed a shorter undercarriage on the L20, which was otherwise like that of the L15 with the wheels independently mounted on pairs of centrally hinged V-struts and with vertical shock absorbing legs to the wing underside. Wheels were sometimes replaced by floats. Intended from the start for serial production, the L20's structure was simplified, with a pentagonal cross-section fuselage lacking the L15's rounded upper and lower surfaces. The fuselage was wooden framed with canvas covering. The overall strength of the structure, which had a safety factor of 12, was emphasised.  The wing was tapered in planform and was built around two spars, though there were two variants of the internal wing structure. The first three aircraft, type L20 A1, had wings stiffened against torsion by internal wire bracing but later aircraft, type L20 B1, used a torsion box formed by plywood skin ahead of the rear spar. Like the later version of the L15, the L20 used a combination of conventional ailerons and unusual wingtip flaps, rotating about an axis well ahead of mid-chord. The ailerons were directly controlled from the cockpit as normal and the tip flaps were linked to them with external rods and cranks. On early examples these flaps were roughly square, with a side less than a half of the chord at the tip, but at some later time they were reshaped to produce wing curved tips. The wings could be detached at the root in about five minutes, reducing the width of the L20 to for road transport on a trailer pulled by a car.  At the beginning of the design and testing period the absence of a suitable, serially produced light aircraft engine was a concern and the wing was therefore mounted so that it could be moved fore and aft to allow for the varying centre of gravity positions resulting from engines of different weight. A glider version was contemplated though not finally used. Instead, the flight programme began with the L20 powered by the Harley-Davidson motor cycle engine used in the L15. By mid 1925 this had been replaced with a new engine, the air-cooled, flat twin Mercedes F7502a, which Klemm had persuaded Daimler's engine group to design and build for the light aircraft market. The cost of flying the L20 was low as its cruise fuel consumption was only 63 mL/km (45 mpg). From 1926 the uprated Mercedes F7502b was fitted. The F7502 was central to the success of the L20, though it suffered from repeated rocker arm failures.  Having failed to persuade the Daimler management to undertake series production of the L20 despite its early successes, in 1927 Klemm left to set up his own company, Klemm Light Aircraft in Sindelfingen, later moving to Böblingen. Thereafter the L20 was often known as the Klemm-Daimler L20 or sometimes the Daimler-Klemm L20. After 1926, new designs appeared under Klemm's name alone; for example the Klemm L25, later Kl25, was a revision of the L20 with a Salmson radial engine.

Operational history.

The 1925 Round Germany Flight involved five circuits over a total distance of. Two early L20s and the twin-engined L21 competed against many aircraft from other German manufacturers. All three Daimler aircraft were very successful in the under class, with the L21 the overall winner, receiving 25,000 Goldmarks (worth £1,250 in 1925) and the two L20's coming second and third and winning another 25,000 Goldmark between them. They also contributed to the award of first prize in the contest between German engined aircraft to Mercedes.  The best known and most significant flight by the L20 was the wintertime crossing of the Alps in early 1926. Flight Magazine hailed this as the "Vindication of the Light 'Plane", in the sense that it showed small aircraft to be a practical vehicle for travel over difficult terrain and in uncertain weather. The pilot was Guritzer and the navigator/engineer von Lansdorff, both from Daimler. The flight began at Daimler's Sindelfingen base on 16 February. No special preparation such as fuel dumps were made in advance and carefully prepared maps were lost overboard early in the flight. The weather frustrated several attempts to cross the Alps but at last the L20 landed in of snow near Zeller See. The return journey reached eastwards, skirting the Alps via Budapest and Vienna and arriving home at Sindelfingen on 16 March.  During 1927 the L20 continued to contest competitions such as the Lilienthal Prize, winning most of the prizes in the lightplane class and making overseas visits such as the one to the UK in July. Private owners also took them on long tours, such as the 1927 North European flights of Anton Riediger but no-one went further with their L20 than Baron Freidrich Carl von König-Warthausen, who set off on 11 August 1928 on a world tour, beginning with a flight to Moscow, then on to Tehran, Calcutta and Singapore. From there he and the L20 crossed to North America by sea but flew across the United States, arriving in New York City on 3 September 1929 after travelling from Berlin.

The Daimler L20, later known as the Klemm-Daimler L20, was one of the first light aircraft to be built in significant numbers. A two-seater with an engine of only, it demonstrated the ability of a small aircraft to cope with flights over the Alps in winter and to make transcontinental journeys of over 36,000 km.

Le Daimler L 20 est un avion monoplan, biplace en tandem de sport construit dans les années 1920. C'est le premier avion dessiné par Hanns Klemm à avoir été construit en série.


Introduction.

Doubly fed electrical generators are similar to AC electrical generators, but have additional features which allow them to run at speeds slightly above or below their natural synchronous speed. This is useful for large variable speed wind turbines, because wind speed can change suddenly. When a gust of wind hits a wind turbine, the blades try to speed up, but a synchronous generator is locked to the speed of the power grid and cannot speed up. So large forces are developed in the hub, gearbox, and generator as the power grid pushes back. This causes wear and damage to the mechanism. If the turbine is allowed to speed up immediately when hit by a wind gust, the stresses are lower with the power from the wind gust still being converted to useful electricity.  One approach to allowing wind turbine speed to vary is to accept whatever frequency the generator produces, convert it to DC, and then convert it to AC at the desired output frequency using an inverter. This is common for small house and farm wind turbines. But the inverters required for megawatt-scale wind turbines are large and expensive.  Doubly fed generators are another solution to this problem. Instead of the usual field winding fed with DC, and an armature winding where the generated electricity comes out, there are two three-phase windings, one stationary and one rotating, both separately connected to equipment outside the generator. Thus, the term "doubly fed" is used for this kind of machines.  One winding is directly connected to the output, and produces 3-phase AC power at the desired grid frequency. The other winding (traditionally called the field, but here both windings can be outputs) is connected to 3-phase AC power at variable frequency. This input power is adjusted in frequency and phase to compensate for changes in speed of the turbine.  Adjusting the frequency and phase requires an AC to DC to AC converter. This is usually constructed from very large IGBT semiconductors. The converter is bidirectional, and can pass power in either direction. Power can flow from this winding as well as from the output winding.

History.

With its origins in wound rotor induction motors with multiphase winding sets on the rotor and stator, respectively, that was invented by Nikola Tesla in 1888, the rotor winding set of the doubly-fed electric machine is connected to a selection of resistors via multiphase slip rings for starting. However, the slip power was lost in the resistors. Thus means to increase the efficiency in variable speed operation by recovering the slip power were developed. In Krämer (or Kraemer) drives the rotor was connected to an AC and DC machine set that fed a DC machine connected to the shaft of the slip ring machine. Thus the slip power was returned as mechanical power and the drive could be controlled by the excitation currents of the DC machines. The drawback of the Krämer drive is that the machines need to be overdimensioned in order to cope with the extra circulating power. This drawback was corrected in the Scherbius drive where the slip power is fed back to the AC grid by motor generator sets.  The rotating machinery used for the rotor supply was heavy and expensive. Improvement in this respect was the static Scherbius drive where the rotor was connected to a rectifier-inverter set constructed first by mercury arc-based devices and later on with semiconductor diodes and thyristors. In the schemes using a rectifier the power flow was possible only out of the rotor because of the uncontrolled rectifier. Moreover, only sub-synchronous operation as a motor was possible.  Another concept using static frequency converter had a "cycloconverter" connected between the rotor and the AC grid. The cycloconverter can feed power in both directions and thus the machine can be run both sub- and oversynchronous speeds. Large cycloconverter controlled doubly-fed machines have been used to run single phase generators feeding Hz railway grid in Europe and run the turbines in pumped storage plants.  Today the frequency changer used in applications up to few tens of megawatts consists of two back to back connected "IGBT" inverters.  Several brushless concepts have also been developed in order to get rid of the slip rings that require maintenance.

Double-fed induction generator.

Double-fed induction generator (DFIG), a generating principle widely used in wind turbines. It is based on an induction generator with a multiphase wound rotor and a multiphase slip ring assembly with brushes for access to the rotor windings. It is possible to avoid the multiphase slip ring assembly, but there are problems with efficiency, cost and size. A better alternative is a brushless wound-rotor doubly-fed electric machine.  The principle of the DFIG is that stator windings are connected to the grid and rotor winding are connected to the converter via slip rings and back-to-back voltage source converter that controls both the rotor and the grid currents. Thus rotor frequency can freely differ from the grid frequency (50 or 60 Hz). By using the converter to control the rotor currents, it is possible to adjust the active and reactive power fed to the grid from the stator independently of the generator's turning speed. The control principle used is either the two-axis current vector control or direct torque control (DTC). DTC has turned out to have better stability than current vector control especially when high reactive currents are required from the generator.  The doubly-fed generator rotors are typically wound with 2 to 3 times the number of turns of the stator. This means that the rotor voltages will be higher and currents respectively lower. Thus in the typical ±30% operational speed range around the synchronous speed, the rated current of the converter is accordingly lower which leads to a lower cost of the converter. The drawback is that controlled operation outside the operational speed range is impossible because of the higher than rated rotor voltage. Further, the voltage transients due to the grid disturbances (three- and two-phase voltage dips, especially) will also be magnified. In order to prevent high rotor voltages (and high currents resulting from these voltages) from destroying the insulated-gate bipolar transistors and diodes of the converter, a protection circuit (called crowbar) is used.  The crowbar will short-circuit the rotor windings through a small resistance when excessive currents or voltages are detected. In order to be able to continue the operation as quickly as possible an active crowbar has to be used. The active crowbar can remove the rotor short in a controlled way and thus the rotor side converter can be started only after 20–60ms from the start of the grid disturbance when the remaining voltage stays above 15% of the nominal voltage. Thus, it is possible to generate reactive current to the grid during the rest of the voltage dip and in this way help the grid to recover from the fault. For zero voltage ride through, it is common to wait until the dip ends because it is otherwise not possible to know the phase angle where the reactive current should be injected.  As a summary, a doubly-fed induction machine is a wound-rotor doubly-fed electric machine and has several advantages over a conventional induction machine in wind power applications. First, as the rotor circuit is controlled by a power electronics converter, the induction generator is able to both import and export reactive power. This has important consequences for power system stability and allows the machine to support the grid during severe voltage disturbances (low-voltage ride-through; LVRT). Second, the control of the rotor voltages and currents enables the induction machine to remain synchronized with the grid while the wind turbine speed varies. A variable speed wind turbine utilizes the available wind resource more efficiently than a fixed speed wind turbine, especially during light wind conditions. Third, the cost of the converter is low when compared with other variable speed solutions because only a fraction of the mechanical power, typically 25–30%, is fed to the grid through the converter, the rest being fed to grid directly from the stator. The efficiency of the DFIG is very good for the same reason.

Doubly-fed electric machines also slip-ring generators are electric motors or electric generators, where both the field magnet windings and armature windings are separately connected to equipment outside the machine.

La cascade hyposynchrone (' en anglais, littéralement machine asynchrone à double alimentation, abrévié en DFIG en anglais) est un dispositif faisant appel à l'électronique de puissance et permettant de commander la vitesse et la consommation en puissance réactive d'une machine asynchrone à rotor bobiné. En cas de réduction de la vitesse, ce montage a l'avantage de ne pas diminuer le rendement, la puissance étant renvoyée dans le réseau. La technique consiste à placer un convertisseur de fréquence entre le réseau électrique et l'alimentation du rotor du moteur.