**2. Chemistry and occurrence**

Plant biomass is a major potential sustainable source of organic carbon. Terpenes, terpenoids and resin acids are a group of non-polar molecules and share a building block, isoprene or isoprenoid [3], as a common elementary unit (**Figure 1**).

Isoprene, the epitomic terpene substance, is one of the most plentifully ethereal hydrocarbon compounds on Earth attributable to the worldwide plenitude of terpenoid biosynthesis, not the other way around. Around 40% of the biogenic volatile natural compounds transmitted by plants are isoprene, and isoprene is the key hydrocarbon distinguished in human breath. Film crowds breathe out more isoprene when watching scenes of anticipation [5].

Based on ancient scientifically verified data, it is found that the expressions "isoprenoid" and "terpenoid" are applied conversely and that there is still no worldwide accord on terminology.

For instance, a few researchers have named "terpene" to allude just to hydrocarbons dependent on an indispensable number of C5 units, and "terpenoid" or "isoprenoid" to assign the entire class of compound dependent on an intrinsic number of C5 units [6].

Such compounds can be in every way called "terpenes," and the expression "terpenoid" ought to be held for compounds, for example, the steroids, which have differing quantities of carbon molecules, however, are originated from a (C5)n structure [7]. Ruzicka considered this multitude of compounds aggregately to be "terpenic" [8]. Nes and McKean employed the expression "isoprenoid" to portray the entire group [9].

**Figure 1.** *Structure of isoprene unit [4].*

*Revisiting the Medicinal Value of Terpenes and Terpenoids DOI: http://dx.doi.org/10.5772/intechopen.102612*

#### **Figure 2.**

*Classification of terpenes and terpenoids.*

Different classes along with carbon units of terpenes and terpenoids are depicted in **Figure 2**.

Terpenes are significant elements of natural oils, which are secondary metabolites synthesized for battling infectious or secreted because of stress conditions. These are extricated from different fragrant plants commonly limited in mild to warm climatic regions like the Mediterranean and tropical nations where they represent a significant piece of the conventional pharmacopeia. They are ethereal, fluid, transparent, and seldom colored, lipid-dissolvable, and dissolvable in natural solvents with a by and large lower thickness than water. They can be isolated from all plant organs, for example, blossoms, buds, leaves, twigs, stems, seeds, roots, wood, fruits or bark, and are accumulated in secretory cells, holes, trenches, glandular trichomes, or epidermic cells [10].

### **2.1 Monoterpene**

The smallest of terpenes are monoterpenes (**Figure 3**). They contain the compound C10H16, come from different flowers, fruits and leaves and are known as the main component of essential oils, fragrances and many structural isomers [11]. Monoterpenes are found in natural scents for example α-pinene, which imparts scent to pine trees [12], and limonene from citrus plants [13]. One of the main purposes of monoterpenes is to attract pollinators or to serve the purpose of repelling other organisms from feeding off of plants [14].

### **2.2 Sesquiterpene**

Sesquiterpenes, containing the chemical formula C15H24 (**Figure 4**), are much larger compounds than monoterpenes and are much more stable in comparison [15]**.** Sesquiterpenes are naturally occurring and found in plants, fungi, and insects and act as a defensive mechanism or attract mates with pheromones in insects [16].

**Figure 3.**

*Sub-classes of monoterpenes with structural example.*

#### **Figure 4.**

*Classification of sesquiterpenes with structural example.*

Gossypol is a sesquiterpene that is present in cotton plants. It has anti-neoplastic properties and might hinder fertility in male people that is the reason it should be taken out from natural oils and different items before human application [17]. Avarol, a sesquiterpenoid that has been displayed to have antifungal and antimicrobial effects, is compelling against AIDS infection [18].

*Revisiting the Medicinal Value of Terpenes and Terpenoids DOI: http://dx.doi.org/10.5772/intechopen.102612*

#### **2.3 Diterpene**

Diterpenes are natural substances that contain the atomic skeleton, C20H32 (**Figure 5**) [19]. Diterpenes have physiologically dynamic compounds, for example, plant development chemicals that manage germination, blooming, switch regenerative cycles (from abiogenetic to sexual multiplication) of plants, and vitamin A activity [20]. Cafestol and kahweol are diterpene alcohols that are found in the oil derived from coffee beans [21].

#### **2.4 Triterpene**

Triterpenes are composed of three or six isoprene units and have the chemical formula C30H48 (**Figure 6**) which includes steroids and sterols with squalene being the biological precursor of all Triterpenes [22]. Triterpenes are produced by animals, plants, and fungi. They play a role as precursors to steroids in animal and plant organisms, and are derived from mevalonic acid [5].

Their properties have been studied for anticancer, antioxidant, antiviral, and anti-atherosclerotic activities [23]. Although, the medicinal uses of tri-terpenes are not quite as recognized as other different types of terpenes but their uses are being continuously investigated by researchers.

#### **2.5 Tetraterpene**

Tetraterpenes are also known as carotenoids (**Figure 7**) that have the molecular formula C40H56 and can be in the category of terpenes because they are made from isoprene units [24]. They are found in all different types of fungi, bacteria, and plants and are mainly responsible for red, yellow, or orange fat-soluble plant and animal pigments [25]. One of the most crucial and common tetraterpenes is betacarotene [26].

**Figure 6.** *Classification of Triterpenes.*

**Figure 7.** *Structural example of tetraterpene.*


**Author details**

**7.** Relatedness: Group interventions in which the family members and friends are engaged are suitable for relatedness [35]. The aim of the interventions must be establishing and maintaining relationships with others, resisting inappropriate social pressure, working in cooperation, preventing and resolving interpersonal conflict, asking for help when neces-

**8.** Community: Deficits in social skills are often seen in forensic groups. Social skills training is the main intervention method for being active in a group [36]. For being in a group, it is also important to make responsible decision to identify and evaluate the problems correctly, making decisions based on ethical and social norms, to evaluate decisions in context, contribute to the welfare of society, accurately identify and evaluate problems, make decisions based on ethical and social norms, consider context in decisions, contribute to well-being of community [29]. Social skills training consists of learning activities that use behavioral techniques that enable individuals to acquire independent life skills for better functioning in their communities. Direct teaching, modeling, role playing, behavior

**9.** Spirituality: The spirituality is the 'meaning and purpose in life, the life force or integrating aspect of the person and transcendence or connectedness unrelated to belief in a higher being' in occupational therapy perspective [37] . The meaning of spirituality is different for everyone, can be participating a religion, visiting religious places (such as churches, mosques, synagogues etc.) regularly and can be different for some praying alone, yoga, meditation, being in the nature, walking and so on. There can be challenges about talking about the beliefs and spirituality with the client and that much of spiritual experience can be culturally influenced [37]. Motivation techniques can be used to find meaning and purpose in life. **10.** Pleasure: Pleasure is one of the subjective experiences of the human need-based experiences to engage in occupations [38]. It influences productivity, restoration and being active to engage occupations [39]. Motivational and increasing self-esteem and confidence

**11.** Creativity: It is stated that 'creativity is part of everyday practice; the use of creativity as a conscious approach; creativity involves risk-taking; creativity needs a supportive environment; and creativity is the use of expressive arts in therapy' [40]. Especially creative arts increase the capacities of offenders, help to explore their own resources, assist them to locate hope and motivation, recognize their interconnectedness with others without

The main challenge is the context because of the complexity of the rules affecting the freedom of the offender and the occupational opportunities [7]. The heterogeneous client population is another challenging condition with in the context. Restricted daily living activities cause the loss of control and autonomy. Time use is another challenging factor, the lack of structured time use

rehearsal, and social reinforcement can be used during the interventions.

interventions can be used to improve pleasure.

**6. Challenges in forensic occupational therapy**

external pressure to comply [41].

sary [29].

66 Occupational Therapy - Therapeutic and Creative Use of Activity

Esma Ozkan1 , Sümeyye Belhan1 , Mahmut Yaran2 \* and Meral Zarif3

\*Address all correspondence to<EMAIL_ADDRESS>
1 Department of Occupational Therapy, Faculty of Health Sciences, Sağlık Bilimleri University, Istanbul, Turkey

2 Department of Therapy and Rehabilitation, Havza Vocational School, Ondokuz Mayıs University, Samsun, Turkey

3 Department of Occupational Therapy, Faculty of Health Sciences, Hacettepe University, Ankara, Turkey


**5. Results and discussion**

The calculation of embedment drill string depth in the mud cake is a difficult process and mostly depends on the interaction between the mud cake and downhole tools. It also depends on the mechanical properties of the mud cakes.

It's more realistic and reliable to predict and estimate the minimum and maximum stresses. The contour plot in **Figure 7** indicates the values and direction of the minimum and the maximum vertical stress.

**Figure 7.** *Contour plot of maximum induced stresses.*

*Modeling and Analysis Techniques for Solving Mechanical Pipe Sticking Problems… DOI: http://dx.doi.org/10.5772/intechopen.107307*

In this contour, it's clear that the maximum stresses will be concentrated at the contact surfaces between the drill pipe and the wellbore house. This is due to the high contact pressure and high friction force between the pipe and mud.

The various failure criteria are resulting during overbalance pressure conditions, which caused mechanical pipe sticking. The contour plot of total deformation shown in **Figure 8** illustrates the severe deformation that happens during the downward movement of the drill pipe. In this case, the deformable part (mud cake) will deforms, while the non-deformable part (drill pipe and well bore sleeve) doesn't.

The equivalent strain in this process is illustrated in the contour plot as shown in **Figure 9**. The relative displacement of both drill pipe and mud cake is represented in their movement downward for drill pipe and upward for mud cake

**Figure 8.** *Contour plot of total deformation.*

**Figure 9.** *Contour plot of equivalent strain.*

The overall deformation occurrence according to the relative interaction between the parts shows that high deformation values will take place around the drill pipe and will cause high mechanical sticking with time as shown in **Figure 10**.

Regarding the high contact forces between the parts, the probability of pipe stick will become serious, and the probability of freeing the pipe against soaking with time will be very difficult. **Figure 11** shows the difficulty of freeing the drill pipe with soaking time. Consequently, calculating the required time before backing off and circulating out is very essential.

**Figure 11.** *The probability of freeing the pipe against soaking time.*

*Modeling and Analysis Techniques for Solving Mechanical Pipe Sticking Problems… DOI: http://dx.doi.org/10.5772/intechopen.107307*

Based on the foregoing, and due to high sticking forces between the contact surfaces along the drill pipe, so the drag force will be inversely proportional to pipe drill depth. **Figures 12** and **13** are an illustration of the relationship between pipe depth and both drag force and the percentage probability of getting stuck.

**Figure 12.** *The relation between pipe depth and drag force.*

**Figure 13.** *The relation between pipe depth and the percentage probability of getting stuck.*


**4. Conclusions**

*Textile Industry and Environment*

**Figure 15.**

*water contaminated with RR141.*

**48**

of the compounds during ozonation. Also, a band at 1050 cm−1

*Variation of the FTIR spectrum of RR141 during ozonation, between 2000 and 4000 cm−1*

formation of organic acids. Additionally, the dyes have absorption at 1500 cm−1

*Analysis by means of atomic absorption of the presence of sodium ion during the recirculation of*

vibrations of the aromatic ring, while that of 1720 corresponds to the vibration of the -COOH group and indicates the formation of carboxylic acids. **Figure 17** shows

for RR141 [15].

C─O bond, and a band located at 1400 cm−1

region between 600 and 2000 cm−1

of secondary amines.

**Figure 16.**

corresponding to NO2 formation, and at 1620 cm−1

RR141 show absorption at 760 and 1720 cm−1

, of stretching of

,

, of COO─ ion stretching, confirm the

. The first one corresponds to

, which indicates the formation

*.*

According to the results, we can conclude the following:

	- Elimination of a good part of the color in the discharges into the environment, decreasing visual pollution.
	- Elimination of the use of other treatments, such as the addition of polymers, or the use of membranes that are effective, but at the same time costly, and do not eliminate the problem.
	- Improvements in the final treatment of wastewater, because the decomposition products of the dyes are more biodegradable than the dyes themselves.
	- Reduction of the consumption of water and salts used in the dyeing, as well as reduction of discharges of salts to the environment. These salts are sulfate and sodium chloride, mainly, and are used during the dyeing to facilitate the diffusion of the dye in the textile material.
	- The recovery of the salts and water used, by itself, makes economically attractive the reuse of spent dyeing baths, especially in the case of reactive dyes, where the salt concentration in the dyeing bath becomes approximately 10% w/v.

**51**

**Author details**

Pablo Colindres Bonilla

provided the original work is properly cited.

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

National Institute of Technology of Mexico, Mexico City, Mexico

\*Address all correspondence to<EMAIL_ADDRESS>
*Chemical and Tinctorial Aspects Related to the Reuse of Effluents Treated by Ozonation…*

*DOI: http://dx.doi.org/10.5772/intechopen.81468*


**1. Introduction**

Endovascular neurosurgery is now the most commonly practiced therapeutic approach for most vascular lesions involving the brain and spinal cord [1].  With expansion of the endovascular devices and techniques, the treatment strategies for cerebrospinal vascular diseases has been refined [3]. Neurosurgeons must have the mindset to embrace and nurture the progress and technologic advances. The pioneers of endovascular neurosurgery considered the impossible and tenaciously stood by their dreams [4]. Their revolutionary ideas and inventions truly reflected their courage, faith, and determination. The shift away from open surgical approaches has had far-reaching implications for how we train neurosurgical residents and fellows and how we certify these individuals once their training is completed [5]. With the maturity of endovascular neurosurgery technology, we need to re-examine the resident and fellow training for neurovascular surgery. This chapter traces the evolution of endovascular neurosurgery and its current role as the dominant and frequently standard therapy for cerebral and spinal vascular diseases.