**6. Perioperative bleeding risk associated periodontal procedures**

#### **6.1 Bleeding risk of periodontal procedures**

The perioperative bleeding risk depends on the extent and invasiveness of the periodontal therapeutic approach. A low bleeding risk has been mentioned for most periodontal interventions such as subgingival instrumentation, conventional surgeries (debridement flaps and regenerative or resective interventions), dental implants placement, or tooth extraction [8]. The bleeding associated with these interventions

*Periodontitis and Heart Disease: Current Perspectives on the Associative Relationships… DOI: http://dx.doi.org/10.5772/intechopen.102669*

could be controlled through local haemostatic measures. On the other hand, a moderate bleeding risk is considered for autogenous bone augmentation procedures including block bone harvesting and sinus floor elevation or interventions associated with secondary intention healing such as free gingival graft placement [71, 72]. The frequencies for low and moderate bleeding associated with periodontal therapies have been reported to be less than 1% and between 2 and 5%, respectively [8].

#### **6.2 Patients undergoing antiplatelet and anticoagulant therapy**

Single antiplatelet therapy such as acetylsalicylic acid (aspirin), clopidogrel, ticlopidine or ticagrelor did not increased the frequency of bleeding events as compared with control patients [73, 74].

Dual antiplatelet therapy usually using the combination of aspirin and clopidogrel may induce a certain risk for post-operative bleeding, which may be managed with local haemostatic approaches [75, 76].

The discontinuation of single or dual antiplatelet therapy before any kind of periodontal approach including dental implant placement is not recommended by current evidence [8].

"Current American Heart Association, American College of Cardiology, Society for Cardiovascular Angiography and Interventions, American College of Surgeons, and American Dental Association, European Society of Cardiology, American College of Chest Physicians Evidence-Based Clinical Practice (AHA/ACC/SCAI/ ACS/ADA/ESC/ACCP) guidelines on perioperative management of antithrombotic therapy do not suggest discontinuation of anti-platelet therapy for low bleeding risk procedures" [77–79].

No increased risk of bleeding has been associated with oral vitamin K antagonistanticoagulant therapy (warfarine, cumarine) in patients receiving dental extraction, minor dental procedures or dental implant placement when compared to patients discontinuing anticoagulant therapy [80, 81]. However, in comparison with non-vitamin K patients, a higher post-operative bleeding risk in patients continuing vitamin K antagonist-anticoagulant therapy and suffering from minor or higher-risk dental procedures have been reported, although post-operative bleeding could be effectively controlled with local haemostatic agents [80, 82, 83].

As for novel/direct anticoagulants such as apixaban, rivaroxaban, betrixaban, edoxaban, and dabigatran, it seems that the interruption of these drugs is not necessary for most dental-periodontal therapies, due to a low incidence of bleeding events associated with these drugs and which can be successfully managed with local haemostatic measures [84–86]. As a positive advancement in the field, a neutralizing agent (idarucizumab) has been developed for dabigatran. However, a higher incidence of delayed bleeding (2 days and later) has been reported in patients not discontinuing novel/direct anticoagulants in comparison with healthy persons [87]. Although, it has been widely used in the past, especially in the era of anti-vitamin K anticoagulants, the low molecular weight heparins (LMWH) bridging strategy should be avoided in patients treated with novel oral anticoagulants (NOAC) as it increases the risk of bleeding, with no benefit on the risk of cardioembolic events. It is reserved for patients with mechanical valve prostheses at high thrombotic risk [88].

However, in CVD patients receiving complex antithrombotic medication a strict communication with cardiologist is mandatory.


**13. Prevention and control**

Prompt diagnosis and treatment of infected individuals and public education of sexually active populations on proper prevention and prophylactic measures for STIs are the foundation of STI prevention and control. To be successful this approach should be supplemented with screening programs to identify individuals with subclinical infections as many, if not most, STIs are transmitted by individuals who do not know they are infected. However, the lack of adequate diagnostic capacity in most tropical settings severely compromises diagnosis and screening for STIs. This is the biggest barrier to addressing the STI epidemic in the developing world. Provision of a minimal diagnostic capacity, both equipment and trained individuals, at the initial point of contact with STI patients would yield enormous benefits. The development of affordable point-of care tests for STIs would also significantly advance efforts for controlling STIs in these countries. Public health education initiatives for STIs should encourage safe sex behavior and emphasize the advantages of prompt access to healthcare for suspected infections. Education is key to changing sexual behavior in high risk groups, especially adolescents and young adults who

of 14 days. WHO recommends the addition of a parenteral aminoglycoside, such as gentamicin, for the therapy of HIV-positive patients. Treatment should be continued until complete healing is achieved. The intracellular residence of *C. granulomatis* makes it

Travel is known to be a major factor in the spread of STIs around the world, particularly in developing countries where STIs are endemic and very high rates are encountered in commercial sex workers. The rapid spread of antibiotic resistance around the world for a number of STIs and the spread of HIV infection are cases in point. It is difficult to assess the risk of acquiring STIs during travel in which sexual acts occur. Poverty and lack of legal enforcement certainly facilitate access to sexually compliant individuals in the developing world. In addition, risk-taking behavior increases when on vacation and often vacations involve higher risk activities than the traveler typically encounters at home. Studies have shown that engaging in sexual activity is the specific reason for travel, i.e. 'sex vacations', in some travelers. Reports of lower condom rate usage and higher rates of engagement in anonymous sex by travelers support a conclusion of increased risk. Travel clinics and physicians advising overseas travelers should counsel travelers about the risks and proper prophylactic regimens available. Travelers should also be strongly encouraged to be tested for STIs upon return if they have engaged in sexual activity. There are high rates of asymptomatic infection for many STIs and long incubation periods can also occur before there is an onset of symptoms. Immigrants and refugees pose a problem to the health care system in developed countries as well. STIs uncommon in the developed world such as chancroid, LGV, and donovanosis present a diagnostic challenge to the physician unfamiliar with these diseases. Incorrect diagnosis and subsequent incorrect treatment can delay resolution of the disease and increase the risk to the patient and sex partners, even permitting local mini-epidemics of new STIs. Health care providers should be aware of uncommon STIs present in their patient's country of origin when evaluating symptoms of

Prompt diagnosis and treatment of infected individuals and public education of sexually active populations on proper prevention and prophylactic measures for STIs are the foundation of STI prevention and control. To be successful this approach should be supplemented with screening programs to identify individuals with subclinical infections as many, if not most, STIs are transmitted by individuals who do not know they are infected. However, the lack of adequate diagnostic capacity in most tropical settings severely compromises diagnosis and screening for STIs. This is the biggest barrier to addressing the STI epidemic in the developing world. Provision of a minimal diagnostic capacity, both equipment and trained individuals, at the initial point of contact with STI patients would yield enormous benefits. The development of affordable point-of care tests for STIs would also significantly advance efforts for controlling STIs in these countries. Public health education initiatives for STIs should encourage safe sex behavior and emphasize the advantages of prompt access to healthcare for suspected infections. Education is key to changing sexual behavior in high risk groups, especially adolescents and young adults who

**12. STIs among travelers and immigrants from the tropics**

somewhat resistant to treatment.

genital infection in this population.

**13. Prevention and control**

are disproportionately afflicted by STIs. Some health care advisors have advocated a policy of treating all sexually active adolescents and adults in a village or locale as a means to controlling STIs, an approach similar to mass treatment with anti-helminthics utilized to control the endemic of intestinal worm disease. This approach may be the single most cost effective mechanism for managing the STI epidemic in developing countries and should be given careful consideration. Although perhaps not applicable for all STIs, certainly for highly prevalent STIs with drugs that are inexpensive, safe, efficacious, and well tolerated, such as metronidazole for treating trichomoniasis, this approach has much merit.

 People in long term monogamous relationships also have greatly reduced risk of STIs and HIV. Vaccines are available for the prevention of HPV infection and potential HIV vaccines are in clinical trials.  Consistent and proper use of condoms has been shown to reduce the transmission of STIs and HIV. Male circumcision has also been shown to be significantly protective against transmission of HIV and STIs. STI treatment should include sexual partners of the index case whenever possible to prevent re-infection and to reduce disease transmission. Due to compliance issues and difficulties in following patients in many locales, directly observed single dose therapies are preferred for the treatment of STIs.

#### **14. The future: Vaccines for STIs**

Vaccination offers the ultimate tool for control of STIs; prevention before exposure. Safe and efficacious vaccines could eliminate the vast majority of STI-associated morbidity and mortality. Unfortunately this goal has only been attained relative to HPV infection (section 9.5) and prospects for additional STI vaccines in the immediate future are remote. In part, this is because the precise correlates of protective immunity have not been well-defined for these STIs. However, some progress has been made in the development of vaccines for genital herpes and *Chlamydia* infection. Three types of herpes vaccines have shown efficacy in animal models: (i) HSV-2 subunit vaccines combined with adjuvant; (ii) gene delivery vehicles, such as vaccinia virus, *Listeria* or *Salmonella typhimurium*, expressing HSV-2 proteins; and (iii) attenuated (replication-defective) HSV-2 viruses. Subunit vaccines based on herpes glycoproteins gD and gB have failed in two human clinical trials. Live attenuated viruses have not been tested in humans to date although they have shown the most promise in animal models. Recent progress in identification of T-cell epitopes mediating asymptomatic versus symptomatic disease manifestation should enhance future development of a herpes vaccine. *Chlamydia* candidate vaccines containing *Chlamydia* major outer membrane protein (MOMP) with HPV major capsid membrane protein L1, recombinant MOMP with cholera toxin, co-expressed *Chlamydia* Porin B and polymorphic membrane protein-D proteins in a *Vibrio cholerae* ghost delivery system, MOMP-based DNA vaccines, and live attenuated *Chlamydia* organisms have each shown efficacy in animal models but none have advanced to human trials.

Although the lack of progression to disease in some individuals infected with gonorrhea, syphilis, chancroid, and granuloma inguinale and the ability of immune responses to contain and clear infections in others in the absence of treatment indicates the theoretical feasibility of vaccination, progress on the development of a vaccine for these STIs has lagged. The syphilis spirochete, *Treponema pallidum*, has a unique molecular architecture and

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the cell envelope consists of a dual membrane structure. The outer membrane is poorly immunogenic, lacking lipopolysaccharide and possessing few integral membrane proteins that could serve as surface antigenic targets for the host immune system. The strong antibody response observed in syphilis is principally generated by lipopolysaccharide and protein immunogens located in the inner membrane where they are inaccessible to this antibody response. To date, research on a syphilis vaccine has not progressed past the identification of these rare outer membrane proteins as candidate vaccine antigens. Development of a gonococcal vaccine has been hampered by the ability of *N. gonorrhoeae* to change surface antigens, especially Type IV pili, deficiencies in current animal models, and the lack of target capsular polysaccharides such as are present in *N. meningitidis*. Two candidate gonorrhea vaccines, utilizing killed whole gonococcal cells or pilus and pilusassociated proteins, have been tested in human clinical trials but neither produced protection. Recent work on gonococcal vaccines has been focused on the identification of potential B- and T-cell epitopes for candidate antigens. The relatively low incidence of chancroid and donovanosis in most developed countries is mirrored by limited research interest towards development of vaccines for *Haemophilus ducreyi* and *Calymmatobacterium granulomatis* infections and there is little in the way of published work or progress on vaccines for these organisms.

#### **15. References**

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1465-6566

**15. References**

**27**

*Spain*

**Re-Emergence of Malaria and Dengue in Europe**

Currently, the emergence/reemergence of several vector-borne diseases in Europe is one of the most important threats for Public Health. In recent years, it is well known that global change have led to drastic modifications in the eco-epidemiology of various tropical and subtropical diseases. Global change can be defined as the impact of human activity on the fundamental mechanisms of biosphere functioning. Therefore, global change includes not only climate change, but also habitats transformation, water cycle modification, biodiversity loss, synanthropic incursion of alien species into new territories or introduction of new chemicals in nature. Consequently a holistic approach is a key factor to assessing the likelihood of vector-borne diseases transmission in Europe. Among these vectors, culicid mosquitoes are probably the most important because of its large vectorial capacity and its

Vector species Distribution Indigenous/exotic Vectorial capacity

Exotic (recently imported)

Exotic (first

in 1979)

reported in Albania

(Portugal), The Netherlands

area, Central Europe

**1. Introduction**

high degree of opportunism (Table 1).

*Ae. albopictus* Mediterranean

*Ae. aegypti* Madeira

Rubén Bueno Marí and Ricardo Jiménez Peydró

*Biodiversidad y Biología Evolutiva, Universitat de València*

Dengue (DEN), Yellow Fever (YF), Chikungunya (CHIK), West Nile (WN), Japanese encephalitis (JE), Saint-Louis encephalitis (SLE), La Crosse encephalitis (LACE), Murray valley encephalitis (MVE), Western equine encephalitis (WEE), Eastern equine encephalitis (EEE), Venezuelan equine encephalitis (VEE), Myxomatosis (MYX), Avian Malaria (AMAL),

Dirofilariasis (DF)

DEN, YF, CHIK, WN, JE, SLE, LACE, WEE, EEE, VEE,

Jamestown Canyon (JC), Sindbis (SIN), Tahyna (TAH), DF

*Laboratorio de Entomología y Control de Plagas, Inst. Cavanilles de*


**1. Introduction**

With one of the largest cattle herds in the world, with almost 215.2 million heads1 according to FAO [1] and IBGE data [2], with almost 90% of this being beef cattle (approximately 193.5 million heads of cattle) and almost 22 million head of dairy cattle, in 2015, the production of beef and dairy products, largely based on extensive systems, has a significant environmental impact, including with a large demand for energy resources, most of which is non-renewable and of fossil origin. The **Figure 1** shows countries with the largest cattle herds, 2000-2014.

1 Emissions generated by other animals will not be analyzed, only those from the raising of cattle. In the case of analyses and the scenarios proposed, the author uses data for the confinement of beef cattle, not considering the herd of dairy cattle which belong to the entirety of the bovine herd.

**Figure 1.**

*Countries with the largest cattle herds, 2000–2014, in millions of heads. Source: Prepared by the authors, based on FAO [1].*

Agriculture is one of the principal GHG emitting activities in Brazil due to, for example, the methane resulting principally from enteric fermentation and the handling of waste, and nitrous oxide from feces and urine deposited by animals [3]. In the last emissions inventory, agriculture was responsible for around 32% of greenhouse gas emissions in the country, without taking into account the emissions created from the use of energy, measured in the part of energy whose contribution is almost 29%, but which includes a part related to the demand of the agricultural sector for energy and energy resources, as well as emissions from the conversion of forests into pasture, calculated in the part related to changes in land use. Agricultural thus contributes, directly or indirectly, to most greenhouse gases produced in the country, as seen in **Figure 2**.

In relation to the demand for energy, the agricultural sector demanded around 14.08% of the total diesel oil used in the country (approximately 7460,000 m3 ) and almost 11.48% of firewood (more than 9000 tons) [4]. In the case of the use of electric energy, the agricultural sector consumed around 5.14% of the final total consumption of electricity in 2015, or 26,870.89 GWh [4].

Despite have a majority renewable energy matrix, as D'Avignon [5] highlights, this does not impede the need for the implementation of complementary renewable energy programs, above all with short-term energy policies, given the environmental limitations on the construction of new hydro-electric power plants with large reservoirs2 , which include the majority of those constructed in Brazil, or the hydric crises which have occurred in recent years, causing serious problems with the supply of electric energy, imposing the need, for example, for rationing and the introduction of non-renewable sources of energy and more sources of GHG emissions, following the insertion of thermoelectric power plants (above all, coal and oil) [6–10]. A way to reduce dependence on hydroelectricity for the generation of electric energy and with a lower environmental impact is a policy of complementarity with new sources of renewable energy generation [5]. One of the possible renewable energy sources is biogas produced through the confinement of cattle.

2 It should be emphasized the hydroelectricity continues to be the principal source in the Brazilian energy matrix. According to BEN, hydraulic energy was responsible for 64% of the total offer of electric energy in 2015 [6].

*Biogas Generation from Bovine Confinement: An Energy Policy Option for Brazil DOI: http://dx.doi.org/10.5772/intechopen.99828*

**Figure 2.**

*Participation of each sector in the GEE emissions, in CO2e, in 2010. Source: [12], p. 18.*


**Abstract**

Plasmonic nanofluids show great interests for light-matter applications due to the tunable optical properties. By tuning the nanoparticle (NP) parameters (material, shape, and size) or base fluid, plasmonic nanofluids can either absorb or transmit the specific solar spectrum and thus making nanofluids ideal candidates for various solar applications, such as: full spectrum absorption in direct solar absorption collectors, selective absorption or transmittance in solar photovoltaic/ thermal (PV/T) systems, and local heating in the solar evaporation or nanobubble generation. In this chapter, we first summarized the preparation methods of plasmonic nanofluids, including the NP preparation based on the top-down and bottom-up, and the nanofluid preparation based on one-step and two-step. And then solar absorption performance of plasmonic nanofluids based on the theoretical and experimental design were discussed to broaden the absorption spectrum of plasmonic nanofluids. At last, solar thermal applications and challenges, including the applications of direct solar absorption collectors, solar PT/V systems, solar distillation, were introduced to promote the development of plasmon nanofluids.

**Keywords:** solar thermal, plasmonic, nanofluid, absorption, nanoparticle


**3. Composting**

*Elements of Bioeconomy*

**90**

**Figure 2.**

*harvested mushrooms, respectively.*

*Mushroom cultivation processes. (a)–(g) represent substrate preparation, mixing and bagging, actively growing mushroom planting material (spawn), inoculation/spawning of substrate bags, Volvariella volvacea growing on banana leaves, and Calocybe indica (milky mushroom) growing on sawdust substrate and freshly*

variety [11, 12]. They are conventionally grown on agro-industrial wastes containing lignin, cellulose and hemicelluloses. In Nigeria and other parts of the world, tons of these wastes are generated annually which, if not managed, will constitute a menace to the environment. Different agro-industrial wastes singly and in combination have been used for the cultivation of different mushrooms such as *Volvariella volvacea*, *Pleurotus* species, *Agaricus* species, etc*.* [13–15]. The waste used in mushroom production includes banana leaves, water hyacinth, sawdust, rice straw, maize

stover, corn cob, cassava peels, grass straws, oil palm processing wastes, etc.

maturity. Mushroom cultivation processes are presented in **Figure 2**.

The first step in mushroom growing is the choice of which mushroom species to grow. The culture of the choice mushroom can be obtained and prepared into the planting spawn, or the spawn is purchased directly from a mushroom laboratory. The second step is sourcing for a readily available substrate within the grower's immediate environment to cut down production cost. This step is followed by the preparation of the growing medium or substrate which may include chopping, breaking, soaking or moistening, depending on the type of substrate. They can be used fresh (rice straw, maize cob, banana leaves, etc.) or composted (sawdust). Some (straws, vines and wood) may require chopping into smaller sizes of 3–5 cm, while others can be used directly (e.g. sawdust) [16]. It is also required that the growth materials are disinfected to rid them of other inherent micro-organisms and insects by applying heat or chemical treatments [17, 18]. The third step in mushroom growing process is the transfer of the spawn or inoculum (planting material) to the growth medium after disinfection. This is done using a standard method in a laminar flow chamber or a locally fabricated inoculation hood, to avoid contamination of the disinfected substrate by unwanted micro-organisms. After inoculation or planting, the substrates are then moved to a dark room or incubation chamber and left for a period depending on the mushroom species that is being grown; it is a time during which the mushroom mycelium ramifies the entire substrate. After incubation, the substrates are subjected to a fruiting condition where the mushroom fruiting body initials or primordia begin to appear and are harvested after

Compost fertilizers are organic fertilizers made from plant and animal leftover that have been decomposed by the existing micro-organism [22, 23]. The main objective of making compost manure is to recycle these nutrients in plants and animal leftover back to the soil for plant growth. The practice improves the soil physical, chemical and biological activities, improving crop yields and nutritional values. It also maximizes the use of available organic resources on the farm and minimizes the use of costly inorganic agrochemicals [24, 25]. Process involved in making compost is referred to as composting. Composting is defined as a biological process in which a micro-organism converts organic materials such as manure, sludge, leaves, peels, animal waste and food waste into a soil-like material called compost in the presence of water and air [26]. It is the main process used to produce stable, high-quality organic fertilizers from organic waste [27].  Compost can be made from crop residues, husks, stovers and agricultural, domestic and industrial wastes that are accessible and available, combined with animal manures. Human wastes can also be composted for crop production, but it is not encouraged due to disease and pathogen transmission [29].

Nigeria is the leading producer of cassava in the world, producing 37 million tons/year on 2.5 million hectares of land [30]. Accompanied with this output is the large volume of cassava peels being released as waste by processing centres all over Nigeria. It is usually burnt or used to feed livestock (most especially small ruminants) as source of protein and roughages. However, not more than 10% of the cassava peels produced is utilized in feeding livestock. The remaining is commonly found in farm and other processing sites as heap that are generally perceived as a nuisance [28]. These materials, however, could be utilized more effectively and sustainably through recycling rather than being destroyed through burning as commonly practiced by many leading to air pollution. Wastes such as cassava peels are rich in crude protein (5.29%) and fat (1.18%) [31]. Utilization of the peels and other agricultural wastes is limited by its low digestibility. Composting will not only reduce toxicity but also convert the resistant lignocellulose material into a more digestible substrate. Preparing compost from wastes offers many advantages. It provides incentive for communities to recover locked nutrients in the wastes, eliminate the problem of waste disposal and increase the manurial values of the materials [32].

Compost can be prepared throughout the year. Three common methods of preparing composts include on the earth/flat surfaces, the use of compost pits and preparation in boxes. Methods adopted are dependent on availability and access to space (**Figure 3**).

Compost manure will regulate soil structure, softens hard soil and improves the water holding capacity of the sandy soil, thus increasing soil aeration and the soil's ability to withstand erosion by wind or water [25]. It requires little or no technical

#### **Figure 3.**

*Composting materials and matured compost; a, b, c and d are composting using bins, poultry manure, cassava peels and finished compost, respectively.*

know-how. It is cheap and can be made on-site where wastes are deposited, thus reducing cost of transport. As an organic fertilizer, it has the ability to release nutrient slowly into the soil, thereby making the effect to last longer, even to the succeeding crops. It creates a good environment for soil microbes, by providing carbon compounds which serve as nutrients for soil micro-organisms and other soil habitats. Compost manure due to its composition is the storehouse of all essential macro- and micronutrients required by plants. When composts are fortified with other amendments, it can be used to control plant diseases and reduce crop losses on the field. [30]'s report indicated that this type of product significantly reduced the need for pesticide, fungicide and nematode application, which could cause environmental pollution. Matured compost should conform to at least one of the four tests outlined below: (i) The carbon to nitrogen ratio (C: N) must be less than 25:1, and seed germination using radish in the compost is at least 90% of control. (ii) The compost is cured and does not reheat to 20°C above ambient temperature. (iii) The compost is cured and there is a 60% weight reduction of organic material. (iv) The material is cured under aerobic conditions without reheating.


**5. Feedstock used for the production of biodiesel**

The feedstock is one of the key factor that plays vital role in the economics of the biodiesel technology. More than 350 oil-bearing crops have been identified as a potential feedstock for the production of biodiesel. The feedstock should fulfill two main requirements (i) large production scale (ii) low production cost [59]. The feedstock availability for the production of biodiesel depends upon the geographical location, local soil conditions, regional climate and agricultural practices of any country. The suitability of feedstock depends upon various factors such as oil yield per hectare, production cost, oil content of the seeds and relevant product properties of the oil. It has been found that, the cost of the feedstock is about 75% of overall production cost of biodiesel [60]. Therefore, selection of cheapest feedstock is a major problem and high relevant to the biodiesel industry. Biodiesel feedstocks are generally categorized into four classes as shown (**Figure 11**).


**1. Introduction**

Organic conductors have been synthesized by chemists [1,2] and their physical properties have been measured by physicists [3,4] for some time now. Chemists still now prepare many new types of organic conductors with novel structures and molecular features [5]. However, most physicists tend to continue to measure "old-fashioned" organic (super)conductors [3,4]. For example, popular salts are κ-(BEDT-TTF)2Cu(NCS)2 [6], where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene; κ-(BEDT-TTF)2Cu[N(CN)2]X (X = Cl, Br) [7,8]; θ-(BEDT-TTF)2[MM (SCN)4] (M = Cs, Rb, Tl; M = Zn, Co) [9]; α-(BEDT-TTF)2[AHg(SCN)4] (A = K, NH4) [10,11]; α-(D)2I3 (D = BEDT-TTF [12]; BETS [13], where BETS = bis(ethylenedithio)tetraselenafulvalene); and (TMTSF)2X (X = PF6, AsF6, ClO4, etc., where TMTSF = tetramethyltetrathiafulvalene) [14]. Most of these examples were first made for more than a quarter of a century ago. This may be because organic conductors prepared recently have had more complicated molecular and/or crystal structures, which are definitely interesting for chemists. However, more complication often implies bulkier molecules, which usually leads to poor conductivity. This might prevent physicists from making the measurements because of the difficulty of finding physical properties in which many physicists are interested. In this circumstance, chemists preparing simple organic conductors might be of interest, especially for physicists. Here, we report the BEDT-TTF, BEST (=bis(ethylenediseleno)tetrathiafulvalene) and BETS salts (Scheme 1) of a simple organic anion, isethionate (HOC2H4SO3 −), the structures and properties of which are reported.

**Scheme 1.** Structural formula of BEDT-TTF, BEST, BETS salts of a simple organic anion, isethionate (HOC2H4SO3 −).

#### **2. Materials and Methods**

Electrical resistivity measurements were performed by the conventional four-probe method using a HUSO HECS 994C1 four channel resistivity meter with cooling and heating rates of ≈ 0.5 K/min. The magnetic susceptibilities of polycrystalline samples of the BETS salt (**3**) were measured from 2 to 300 K using a Quantum Design MPMS-2S SQUID magnetometer. The data were corrected for a contribution from the sample holder (aluminum foil), and the sample's diamagnetic contribution was estimated from Pascal's constants. X-ray diffraction data were collected with a Rigaku Rapid II imaging plate system with a MicroMax-007 HF/VariMax rotating-anode X-ray generator with confocally monochromatic Mo*K*α radiation.

BEDT-TTF and isethionic acid sodium salt (HOC2H4SO3Na) were purchased from Tokyo Chemical Industry and Kanto Chemical, respectively, and used without any further purification. BEST and BETS were prepared according to the literature methods [15–17]. The electrocrystallisation of BEDT-TTF, BEST and BETS with HOC2H4SO3Na and 18-crown-6 ether in PhCl + 10% of EtOH produced black crystals.

The electronic states of the cationic and neutral donors and anions of **3** were calculated using the GAMESS software package [18] at the BY3LP 6-31G\* level (SBKJC core potentials for iodine) using geometries determined by the X-ray analyses. All GAMESS input options used in these calculations are shown in Supporting Information. The input files were prepared using Facio [19,20]. Population analyses were performed using the Multiwfn software package (version 3.6, Beijing Kein Research Center for Natural Science, Beijing, China) [21], which calculated Hirshfeld populations from the output files of GAMESS. The resultant point charges of all the atoms of each molecule were used for Madelung energy calculations, which were performed with the Gulp program package [22] version 5.1, with a "molecule" option to restrict the calculations to only intermolecular Coulombic repulsions; namely, the effect of intramolecular repulsions was excluded.

#### **3. Results**

Table 1 shows the crystallographic data of α-(BEDT-TTF)3(HOC2H4SO3)2 (1), β-(BEST)3(HOC2H4SO3)2·H2O (2) and α-(BETS)2(HOC2H4SO3)·H2O (3).

**Table 1.** *Cont.*

### *3.1.* α*-(BEDT-TTF)3(HOC2H4SO3)2 (1)*

α-(BEDT-TTF)3(HOC2H4SO3)2 (**1**) crystallizes in the space group *P*21/*c*. One and a half of BEDT-TTF and one isethionate are crystallographically independent. Figure 1a shows the crystal structure of **1**. The structure has alternating donor and anion layers propagating along the *a* axis. The structure of the two-dimensional conducting BEDT-TTF layer possessing an α-type packing motif is shown in Figure 1b. There are many interstack short S···S contacts, suggesting that the salt is a 2D conductor. However, the donor-to-anion ratio of 3:2 indicates that there is a BEDT-TTF trimer, in which two holes are located that form a spin dimer. Therefore, the structure suggests that the salt is a band insulator. Actually, the electrical resistivity measurements (Figure S1) indicate that the salt is a semiconductor with ρRT = 1.15 × 102 Ω·cm and *E*a = 190 meV. The molecular arrangement of isethionate in an anionic layer is shown in Figure 1c. Intermolecular hydrogen bonding between the hydroxyl group and an oxygen atom of a nearest neighbor's sulfo group (O···O = 2.861(2) Å) forms a 1D hydrogen bond chain along the *b* axis. In addition, there is an inversion centre in the anionic layer, indicating that the anion layer is not polar.

**Figure 1.** Crystal structure (**a**); arrangement of the donor layer (**b**), where dashed lines indicate short S···S contacts (<3.7 Å); and structure of the anionic layer (**c**) of **1**.