6.3. Inability to tolerate recipient's discomfort

Another motive for organ donation was one's difficulty in tolerating recipient's discomfort. Love for their sick family members had made the participants feel responsible and decide on doing something for solving their patient's problems. Their patient's pain, suffering and discomfort cause a great inconvenience and irritation which lead them to the decision of organ donation. They hoped that organ donation alleviate their patient's problems [14–34, 36].

#### 6.4. Spiritual motives for donation

Religious beliefs played a significant role in motivating to organ donation. Some of them believed that donation was a way for expiating their past sins. They referred to faith in God, reliance on Him, and hope for a successful transplant as the important motives for organ donation. Some of them even accused themselves of causing their family members to develop organ failure and believed that donation was a way for alleviating their feelings of guilt. Such a practice was particularly common among the parents of sick children. Some of them considered donation as a God-approved practice, and noted that God has helped them donate their organs. They noted that they donated their organs for gratifying God and believed that he sees it and help them in all bad situations.

#### 6.5. Greater success rate of organ transplantation

The category is the greater success of organ transplantation. In other words, obtaining information and realizing the greater benefits of organ transplantation had motivated the participants to opt for organ donation. Some of them reported that they had never thought about donation until obtaining information from their patient's physicians. However, after obtaining adequate information, they had made an irreversible decision about organ donation. Accordingly, a major motive for organ donation was the lower likelihood of organ rejection.

be considered. Less common methods like hypnotherapy and "Quality of Life Therapy"

Organ Donation and Transplantation: "Life after Death" http://dx.doi.org/10.5772/intechopen.76962 29

Moreover, family members as well as caregivers of transplant patients show increased psychological strain before and after transplantation. Family counseling, and psychotherapeutic support, can help reduce psychological strain, thus also maintaining the valuable social support provided by care givers and family members of the transplant patient. Henceforth, the family and care givers should also be considered in psychosocial evaluation to overcome the problems.

In view of ethical, legal and political issues, it was deemed important to obtain some opinion about alternative methods to increase organ donation rates. Financial incentives were given to increase organ donation. Many in both donor and non-donor groups were given a reasonable incentive. Education and dissemination of information about donation and transplantation was important to increase organ donation rates. There was nearly universal agreement that implied consent (presumed consent) should not be tried. The use of financial incentives was not markedly opposed (some accepted the idea of funeral expense reimbursement), although there was not strong support either. In general, methods to increase organ donation had not been well thought out by either donors or nondonors indicating, perhaps, that the assumption of altruism

8. Responsibilities of nurses in organ donation and transplantation

Organ and tissue transplant nurses need comprehensive and scientific knowledge. They include the evaluation and management of deceased donors, transplant recipients, potential donors or live donors, teaching and counseling of transplant recipients and live donors related to self-care management, healthy life and a peaceful death when this is imminent. This is

Nurses have important role in the development of a successful transplantation program. They are key members of the team that works to deliver care to patients and relatives, through the use of technological, logistic and human resources, with a view to coordination, care, education and research on organ and tissue donation and transplantation. Therefore, the nurses need adequate knowledge on the principles of good ethical principles and should have resources available for them to assess patient's risks and social issues related to organ transplants and donation. The researchers hope that the future studies will encourage further researches on the

The organ donation decision is a complex one, based strongly on personal beliefs. There are some factors, such as religious and cultural beliefs, that are seemingly intractable and are often

have also been utilized for overcoming the challenges.

7.2. Alternative methods to increase donation

or motivation is the best way to increase the donation rates.

important in order to improve the posttransplant quality of life.

role and responsibilities of nurses.

9. Conclusion


**2.2 Drivers for RWHS**

Rainwater Harvesting System has been used in the water supply system for many years, and has been around for this reason:

1.Water Scarcity

Water scarcity may be due to a lack of adequate surface area and improper control of groundwater resources, polluted land, and groundwater resources and insufficient support for programs to harness and distribute water.

*Smart Rainwater Harvesting System for Sustainable Agricultural Irrigation and Drainage System DOI: http://dx.doi.org/10.5772/intechopen.104442*

#### 2.Reduce flooding and erosion

This system can help reduce erosion around downspouts and in the garden. It controls the stormwater run-off.

3.Reduce water bills

The use of rainwater can substantially reduce the cost to supply main water services. When needed, the rainwater acts as a substitute for a backup source.

4.For sustainable agriculture

The collection of rainwater can be used to boost plants and gardens too. The salt accumulation can be flushed from plants and soil using collected water. Harvested rainwater is usually free of different forms of pollutants and man-made toxins. Rain is also chlorine-free.

#### **2.3 Benefits of the rainwater harvesting system**

The harvesting of rainwater is the element of sustainable agriculture and tends to bring a variety of value not just for users but also environment and government (**Table 1**).

## **2.4 Working principle of the rainwater harvesting system**

Nowadays, the rainwater harvesting system is well known to the public regarding its function and benefits. However, the working process still has the same basic method and component. There are six basic components for a domestic rainwater harvesting system:

• The catchment surface: Surface allowing water to collect from the rain, such as a rooftop. The size of the catchment area determines how much rainwater is harvested.

#### **Table 1.**

*Benefits of the rainwater harvesting system.*


**Hugo Gamboa**

Hugo Gamboa, Prof. Dr. received his Ph.D. degree in electrical and computer engineering from the Instituto Superior Tecnico of University of Lisbon (IST UL), in 2007. He is a Co-Founder and ´ the President of PLUX, a company that develops bio-signals monitoring wearable technology. He is currently a Researcher at the Laboratory for Instrumentation, Biomedical Engineering and Radiation Physics (LIBPhys), Faculdade de Ciencias e Tecnologia of NOVA University of Lisbon (FCT NOVA), ˆ where he is also an Associate Professor with Habilitation at the Physics Department. Since 2014, he has been a Senior Researcher at the Fraunhofer Center for Assistive Information and Communication Solutions (AICOS). His research interests include bio-signals processing and instrumentation.


**Multiple Sclerosis and Its Relationship with Oxidative Stress, Glutathione Redox System, ATPase System, and Membrane Fluidity**

Genaro G. Ortiz, Fermín P. Pacheco‐Moisés,

Erandis D. Torres‐Sánchez, Tanya E. Sorto‐Gómez,

Mario Mireles‐Ramírez, Alfredo León‐Gil,

Héctor González‐Usigli, Luis J. Flores‐Alvarado,

Erika D. González‐Renovato,

Angelica L. Sánchez‐López,

Margarita Cid‐Hernández and

Irma E. Velázquez‐Brizuela

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/64737

#### **Abstract**

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) with a focus on inflammation, demyelination, and damage to axons leading to neurological deficits. MS pathology is associated with excessive reactive oxygen species (ROS) and generation of reactive nitrogen species (RNS), causing oxidative/nitrosa‐ tive stress. Deregulation of glutathione homeostasis and alterations in glutathione‐ dependent enzymes are implicated in MS. Reactive oxygen species enhance both monocyte adhesion and migration across brain endothelial cells. In addition, ROS can activate the expression of the nuclear transcription factor‐kappa, which upregulates the expression of many genes involved in MS, such as tumor necrosis factor‐α and nitric oxide synthase, among others, leading to mitochondrial dysfunction and energy deficits that result in mitochondrial and cellular calcium overload. Loss of mitochondrial membrane potential can increase the release of cytochrome c, one pathway that leads to neuronal apoptosis. Clinical studies suggest that omega‐3 long‐chain polyunsaturat‐ ed fatty acids (PUFAs) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have anti‐inflammatory, antioxidant, and neuroprotective effects in MS and animal models of MS. Here, we review the relationship of oxidative stress, the

© 2016 The Author(s). Licensee InTech. 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, provided the original work is properly cited.

glutathione redox system, the ATPase system, and membrane fluidity with the development of MS. In addition, we describe the main findings of a clinical trial conducted with relapsing‐remitting MS patients who received a diet supplemented with 4 g/day of fish oil or olive oil. The effects of PUFAs supplementation on the parame‐ ters indicated above are analyzed in this work.

**Keywords:** multiple sclerosis, oxidative stress, mitochondria, membrane fluidity, AT‐ Pase

#### **1. Introduction**

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) with partially known etiology. It is the most common cause of neurological disability in young adults. Nutrition is commonly accepted as one of the possible environ‐ mental factors involved in the pathogenesis of MS. Omega‐3 polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are fatty acids that possess several carbon–carbon double bonds. A diet supplemented with PUFAs has clinical and biochemical effects in patients with autoimmune diseases such as MS. Eicosapen‐ taenoic acid and DHA are found in high proportions in fish oil, and these molecules may have anti‐inflammatory, antithrombotic, antioxidant, immunomodulatory functions, and neuro‐ protective effects on the synaptogenesis and biogenesis of the neuronal membrane. Oxidative stress (OS) that is characterized by excessive production of reactive oxygen species and a reduction in antioxidant defense mechanisms have been implicated in the pathogenesis of MS. In consequence, a reduction in this phenomenon could be beneficial for MS patients [1]. In this work, we describe the relationship of several oxidative stress markers (glutathione redox system, mitochondrial ATPase activity, and membrane fluidity) with the development of MS. Furthermore, we describe the main findings of a clinical trial conducted with relapsing– remitting MS patients who received a diet supplemented with 4 g/day of fish oil or olive oil.

Pathologically, MS is characterized by perivenous infiltration of lymphocytes and macro‐ phages in the brain parenchyma. There are four clinical manifestations of MS: relapsing– remitting, primary progressive, secondary progressive, and progressive‐relapsing. The MS lesions are typically scattered, and the clinical picture can vary from a benign self‐limiting disorder to severe and highly disabling disease. MS is a multifactorial disease involving genetic, immunological, and environmental factors that trigger the autoimmune process leading to the pathological changes of the disease. In this regard, it has been proposed that a viral infection in which self‐antigens that generate molecular mimicry with myelin proteins cause a loss of tolerance against it, which results in the destruction of myelin mediated by activated T lymphocytes in white matter of the brain and sometimes extending into the gray matter, resulting in defects in the conduction of nerve impulses that leads to symptoms, depending on the affected site of the brain or spinal cord [1] (**Figure 1**).

According to the areas of myelin destruction, sensory or motor symptoms are affected (balance or vision disorders). The symptoms can change between an "outbreak" or relapse (emergence of new neurological symptoms or worsening of previous ones) and remission. Demyelinating lesions or "plaques" of different sizes and locations are spread throughout the CNS, and the onset of symptoms and response to treatment is unique to each patient [2].

glutathione redox system, the ATPase system, and membrane fluidity with the development of MS. In addition, we describe the main findings of a clinical trial conducted with relapsing‐remitting MS patients who received a diet supplemented with 4 g/day of fish oil or olive oil. The effects of PUFAs supplementation on the parame‐

**Keywords:** multiple sclerosis, oxidative stress, mitochondria, membrane fluidity, AT‐

Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS) with partially known etiology. It is the most common cause of neurological disability in young adults. Nutrition is commonly accepted as one of the possible environ‐ mental factors involved in the pathogenesis of MS. Omega‐3 polyunsaturated fatty acids (PUFAs) such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are fatty acids that possess several carbon–carbon double bonds. A diet supplemented with PUFAs has clinical and biochemical effects in patients with autoimmune diseases such as MS. Eicosapen‐ taenoic acid and DHA are found in high proportions in fish oil, and these molecules may have anti‐inflammatory, antithrombotic, antioxidant, immunomodulatory functions, and neuro‐ protective effects on the synaptogenesis and biogenesis of the neuronal membrane. Oxidative stress (OS) that is characterized by excessive production of reactive oxygen species and a reduction in antioxidant defense mechanisms have been implicated in the pathogenesis of MS. In consequence, a reduction in this phenomenon could be beneficial for MS patients [1]. In this work, we describe the relationship of several oxidative stress markers (glutathione redox system, mitochondrial ATPase activity, and membrane fluidity) with the development of MS. Furthermore, we describe the main findings of a clinical trial conducted with relapsing– remitting MS patients who received a diet supplemented with 4 g/day of fish oil or olive oil.

Pathologically, MS is characterized by perivenous infiltration of lymphocytes and macro‐ phages in the brain parenchyma. There are four clinical manifestations of MS: relapsing– remitting, primary progressive, secondary progressive, and progressive‐relapsing. The MS lesions are typically scattered, and the clinical picture can vary from a benign self‐limiting disorder to severe and highly disabling disease. MS is a multifactorial disease involving genetic, immunological, and environmental factors that trigger the autoimmune process leading to the pathological changes of the disease. In this regard, it has been proposed that a viral infection in which self‐antigens that generate molecular mimicry with myelin proteins cause a loss of tolerance against it, which results in the destruction of myelin mediated by activated T lymphocytes in white matter of the brain and sometimes extending into the gray matter, resulting in defects in the conduction of nerve impulses that leads to symptoms,

depending on the affected site of the brain or spinal cord [1] (**Figure 1**).

ters indicated above are analyzed in this work.

Pase

150 Trending Topics in Multiple Sclerosis

**1. Introduction**

**Figure 1.** Immune‐mediated destruction of myelin components in multiple sclerosis. Pathway Builder Online Tool was used to draw the figure [27].


*<IP_ADDRESS> Indexing*

At the indexing stage, now known as coding, the thematic framework was applied to data systematically by annotating the transcripts with numerical codes from indexing and supported by short text descriptors to elaborate index headings. The qualitative software Atlas ti. 8 was used for all indexing work. The transcript data also can be managed easily and systematically.


**1. Introduction**

Mg-alloys are being considered as one of the most versatile material choices among the structural materials that exhibit both energy efficiency and environmental benefits. Mg-based materials (alloys and composites) have enormous and unlimited potential to replace aluminum, steel, and structural plastics in diverse industrial and commercial sectors such as automotive, aviation, defense, biomedical, sporting equipment, consumer electronics, etc. These applications result from the need to use magnesium and its alloys as a material with favorable physical properties, especially high relative strength (Rm/ρ). Due to the good casting properties of magnesium, it was used primarily in cast structural elements. Wrought alloys have been used on a smaller scale so far, but material research and plastic formability processes to produce semi-finished products from magnesium alloys are currently under intensive development. The development is caused by the possibility of using various types of light structures in the construction, including vehicles made of magnesium-based materials, for which, for example, thin sheets are the

basic initial material. This is mainly due to the attempt to reduce the weight of the structure and ensure adequate strength.

The interest in magnesium alloys for various structural elements, e.g., for the aviation industry, dates back to the 1940s. Examples of applications concerned, for example, the Northrop XP-56 plane, in which virtually all parts exposed to elevated temperature were made of magnesium and its alloys [1], B-36 bomber or [2], the S55 helicopter by Westland Aircraft Ltd. (1950 r.) [1, 3].

In later years, the use of magnesium alloys for aircraft structural elements was significantly limited, which was mainly due to the rapid corrosion of alloys (the main disadvantage), opinions about the flammability of magnesium, low metallurgical purity, low strength, high processing costs through plastic formability and poor machinability [4–7].

Since the beginning of the twenty-first century, there has been a renewed, significant increase in interest in magnesium alloys for applications in the aerospace industry. It results from the development of new coatings that can protect alloys against corrosion, new alloys, new technologies of obtaining semi-finished products by casting methods, and the improvement of various plastic forming technologies, which significantly improves the properties of the product and allows the use of these alloys wherever engineers look for very light construction elements, relatively durable and with anticorrosion protection at the same time [8–10].

The main problem in the development of techniques for processing magnesium alloys with metal forming methods is low formability [4, 11]. Low deformability at room temperature as well as temperature increased to 200°C of magnesium alloys result from a limited number of hexagonal lattice slip systems. The test results show that the microstructure of Al-Mg-Zn alloys deformed at temperatures up to 200°C shows bands slip and deformation twins [11]. In the range from 200 to 300°C, limited dynamic recovery and the formation of nuclei of dynamic recrystallization are observed. Continuous dynamic recrystallization takes place above 300°C, which results in an almost twofold increase in formability.

Metal forming of magnesium and its alloys is carried out, depending on the content of alloying elements, only in a narrow temperature range. Grains with an average diameter of up to 10 μm were obtained in magnesium alloys by thermoplastic treatment. The fragmentation of the grains below 10 μm is only achieved by introducing large deformations. The use of unconventional methods of deformation allows for obtaining the grinding of magnesium alloys to sub-micrometric or nanometric sizes. Therefore, these deformation methods constitute a very significant support for conventional forming methods [12–14].

In magnesium alloys, deformation processes are carried out at an elevated temperature. Therefore, it is practically impossible to obtain nanometric grain sizes obtained by the development of shear bands. The most common methods of large deformation, leading to the grinding of the grains of magnesium alloys, are equal channel angular pressing (ECAP) [15, 16] or hydrostatic extrusion [14, 17].

Basic magnesium alloys for metal forming contain up to 8% Al and the addition of Mn (up to 2%), Zn (usually up to 1.5%), Si (about 0.1%), and traces of Cu, Ni, Fe. There are three basic groups of magnesium alloys for metal forming. The first group includes mainly alloys with the addition of aluminum, zinc, and manganese. The second group includes alloys containing mainly the elements Zn, RE, Y, Zr, Th, and the third group, which is in the phase of intensive research, consists of new ultralight alloys containing lithium.

Magnesium alloys for metal forming are still used to a relatively small extent, which results from technological difficulties in metal forming and high production costs [13, 18, 19]. The main disadvantage of magnesium and its alloys is low deformability at ambient temperature, which results from the type of crystal lattice. At ambient temperature, only one in-plane glide system (0001) is active. In addition to low temperature slip, a significant amount of twinning is observed in magnesium alloys.

Hot forming of magnesium alloys, depending on the chemical composition and deformability, is performed using the following methods [20, 21]:

The formability effect of magnesium alloys has been recently also used in a relatively new solid-state joining process, under the influence of frictional heat, i.e., Friction Stir Welding (FSW). There is no melting involved in the process unlike conventional Fusion welding processes. This method gives very good results in the creation of strong joints, competitive to other joining techniques that require additional joining materials (e.g., riveting, bolted connections, welding, and others). Joining elements (e.g., sheets) made of magnesium alloys with this technique are very effective and require careful selection of process parameters, taking into account the special features of the plasticization of magnesium alloys and the stirring effect in the joint area [4, 22–24].


**5. Conclusion**

At present, professional development is an area of growing interest, mainly due to its implicit consequences, such as self-esteem, self-efficacy, motivation, job satisfaction, and employability [70] the performance of various job duties and responsibilities [23] and the increase it provides in job satisfaction [71]. Thus, such development is relevant to both the workers themselves and the labor and development organizations of the country. As a result, investments in actions aimed at professional development have grown in the international scenario.

As discussed throughout this chapter, professional development should be understood as a construct that goes beyond the mere sum of a set of courses carried out throughout the career because it is a process of maturing the reflexive capacity. So, the most important is not whether professional development comes from formal or informal learning processes. What matters is that such development is characterized as a growing process of awareness and mastery of know-how at work. This is evidenced in different researches that point to reflective practice as an important element for professional development processes [26, 27]. Therefore, in addition to promoting training and development events for specific activities, leaders should encourage a critical and reflective vision in their respective work teams with a deliberately planned direction.

It is also necessary for leaders to understand that the workplace is a complex social system made up of peers who consistently coregulate each other's learning [72]. Thus, if leaders invest in social interactions, they can foster informal learning at work, transforming everyday work practice into a space for the continuous production of collective knowledge.

So, we can conclude that professional development of subordinates is directly connected with leadership style because this development is understood as the growth and maturation of knowledge, skills, and attitudes acquired throughout workers' lives, as a result of learning-atwork actions. And learning-at-work actions depend on leadership decisions.

But while it is important for leaders to act to provide support and development opportunities for their subordinates, care must be taken that leadership does not create unhealthy dependency. Dependence on subordinates constrains their growth and autonomy. Therefore, emerging leadership approaches value the leader's role of coaching roles, with concepts of self-leadership, super leadership, and leadership reinforcement [73]. The challenge posed to the leaders of the twenty-first century, therefore, is to promote and encourage the professional development of their subordinates in a consistent and individual way but without stifling their initiatives and the ability of each one to self-engineer his or her own career.


**5. Diagnosis**

*Goiter - Causes and Treatment*

**2.11 Reproductive function**

**Figure 2.**

**3. Graves' disease**

**3.1 Presentation**

**4. Pathogenesis**

gynecomastia and erectile dysfunction.

*Patient of Graves disease showing diffuse goitre and eye signs.*

Menstrual irregularity is common. Fertility may be reduced, and if conception takes place, there is an increased risk of miscarriage [16, 17]. The increased rate of conversion of androgens to estrogenic by-products may be the mechanism for

Popularly known as Robert Graves' disease in English speaking world and as Von Basedow's disease in Europe, although disease was first described by Parry in 1825 [11].

Graves' disease characteristics include goitre and thyrotoxicosis; common associated features include orbitopathy (GAO) and dermopathy. The thyroid histology suggests autoimmune thyroiditis with the presence of lymphocytic infiltrate.

The TSHR is a G protein coupled receptor. The TSHR is the primary auto antigen of Graves' disease, experimentally proven with mice antigen antibody studies [18].

**4.1 The major antigen of Graves' disease: the thyrotropin receptor**

**50**

It is always better to test TSH and T4 rather than testing TSH alone, measuring both T4 & TSH increases diagnostic accuracy. In case of overt hyperthyroidism T3 and T4 are high and TSH is low and in subclinical disease T4 is usually normal TSH is usually suppressed, and T3 is normal or increased.

TSH-Receptor-Ab (TRAb) is a specific biomarker for Grave's Disease. Immunoassays used nowadays do competitive assays which measure Thyroid Receptor binding inhibitory immunoglobulins (TBII) [19]. Bioassays can differentiate between blocking and stimulating TRAB but its time consuming and a costly affair.


**Acknowledgements**

Everyone who contributed the article success peer-reviewers, UNSPLASH, my wife, Peace J. Allison, for typing and Love and Unity Humanitarian Foundation nonobligatory support grant.


**Treatment of ANCA-Negative Small Vessel Vasculitis**

Christina G. Katsiari, Theodora Simopoulou and Lazaros I. Sakkas

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/54272


**Table 1.** *Cont.*

#### **7. In Conclusions: Pastoral Theology in the Era of Eco-Anxiety**

This article has studied the challenges and possibilities related to eco-anxiety for pastoral care. Many observations have been made about therapeutic encounters in general, including various forms of spiritual care. The wider context related to pastoral theology as a whole has been much present and is given more attention in these final comments, together with its relation to eco-theology.

The recent efforts to integrate ecological theology and pastoral theology (see LaMothe 2016; McCarroll 2020; Swain 2020; cf. Clinebell 1996) are very relevant for the topic of this article. This article has focused on the emotional and psychosocial dimensions of ecological issues, but naturally, the wider spheres of action and various forms of proenvironmental behavior are interrelated with the psychological dimension. Action may help to channel eco-anxiety constructively, but if there is no space for emotion work, people may burn out (Ray 2020; Hoggett and Randall 2018; Nairn 2019). Indeed, some environmental organizations nowadays include eco-emotion workshops and support procedures in their work (see, e.g., the discussion in Weber 2020). There may thus be an element of pastoral care in the ecological activities of congregations and other collectives, and the explicit offering of such support is an important thing to consider.

In general, participating in various kinds of environmental action usually helps with various difficult eco-emotions, and there is a rich literature about various ways in which religious communities can participate in this (see, for example, the materials produced by ecumenical and denominational environmental movements, such as Laudato Si' Movement 2022; A Rocha 2022; World Council of Churches 2022). The potential strengths and challenges for various denominations in encountering eco-anxiety is a topic for future research (for some reflections on certain denominations, see Pihkala 2016a; Ward 2020).

Various kinds of rituals can be organized in relation to eco-anxiety and other ecoemotions (Pihkala 2021), and sometimes, rituals related to ecological concerns have implicit dimensions related to the processing of eco-emotions (cf. Fredericks 2021). While these rituals are maybe not pastoral care per se, if the caregiver is aware of these kinds of methods, they can be recommended to people on suitable occasions. Engaging in spiritual practices can help both the caregiver and the "client" to process their eco-anxiety (cf. Malcolm 2020b). The author has written elsewhere of the need for religious leaders to work critically with eco-guilt, eco-anger, and ecological grief and sadness in spiritual care, rituals, and wider action (Pihkala 2022b). Case examples in English are available, for example, about ways to encounter ecological shame via creative Christian worship (Powell 2019) or ecological grief via outdoor spiritual practices (Hirschfeld and Blackmer 2021; see also many articles in Malcolm 2020a).

The education and formation of pastoral care providers is an area that needs attention in relation to eco-anxiety. First of all, many who undergo such training are young of age, and many of them feel eco-anxiety in some form. They require support from their teachers (cf. Pihkala 2020b). Second, students can be taught constructive ways to encounter eco-anxiety, as has been the aim in Calder and Morgan's pioneering approach (Calder and Morgan 2016). Teaching about eco-anxiety and eco-emotions should be included in theological seminaries and universities. Furthermore, pastors, counselors, and other providers of pastoral care may find it difficult to devote time to learn more about contemporary issues such as eco-anxiety in the midst of their daily life and work. One potential means to help in this is to organize workshops where various professionals focus on environmental issues, including their emotional dimension. Various frameworks have been applied to the process of transformation of identity and attitudes that the ecological crisis requires, such as the "ecological conversion" championed by Francis (2015) and the "affective transformation" delineated by environmental scholar Verlie (2022).

It is notable that anxiety researcher and philosopher Kurth (2018) discusses the positive sides of anxiety often through the examples of religious figures, such as John Woolman and Martin Luther King. Kurth points out that it was exactly anxiety that caused these people to act: they felt problematic uncertainty about moral issues, and this anxiety did not let them go. They were able to cultivate anxiety as a moral emotion and not to stifle it or run away from it. This dynamic can be the positive power of eco-anxiety: if it does not become too intense, it causes people to "stay with the trouble" (see Haraway 2016) and search for ways to practice morality and responsibility, even amidst ambiguous circumstances. Religions may offer people sources of existential resilience, which help to bear eco-anxiety, but this needs effort and intention since religion can also become a hiding place from the troubles of the world.

**Funding:** This research was supported by a personal grant from Finnish Cultural Foundation, granted in February 2019 (no grant number given).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Acknowledgments:** The author expresses gratitude to the two anonymous peer reviewers for their feedback about how to improve the article.

**Conflicts of Interest:** The author declares no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.


*2.1.2 Surfaces textured by the plasma spray process*

Plasma spray is the type of plasma spray treatment that has been most used, which is elaborated with the ionized flame of a gas heated between 10000°C and 30000°C,

#### **Figure 3.**

*Representative SEM images with different magnifications of the surface micro grooves resulting from the machining process, produced by the passage of the cutting tool.*

#### *Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

and the particles are launched at high speed against the implant body. Upon contact, these particles cool and solidify. Plasma spray is used to apply and incorporate Ti (titanium) and HA (hydroxyapatite) onto the implant surface [14].

Titanium plasma spray is formed by coating the implant with ionized gases by thermal spraying with titanium plasma spray. In this method, the ionized flame of a gas is launched against the implant wall at an elevated temperature between 10000°C and 30000°C. With this change, there is an acceleration of blood absorption, due to the effect on the wettability of this surface, there is an increase in the surface contact area, promoting better osseointegration [14, 15]. The titanium particle is fused on the surface, forming a ~ 50 μm thick layer, with the resulting coating being between 10 μm and 40 μm, increasing the surface of the implant. Herrero-Climent et al. [16], carried out a comparative study between plasma spray titanium (TPS) and titanium oxide blasted surfaces, demonstrating that the TPS surface presented a unique pattern of bone matrix formation when compared to the titanium oxide blasted surface.

Meanwhile, the treatment for coating with apatite nucleation occurs through three stages: alkaline treatment, thermal treatment, and immersion in a synthetic solution equivalent to blood plasma. This layer is obtained by spraying the plasma spray of hydroxyapatite onto the implant surface [15]. Roughness depends on the size of the particles, their adhesion, the speed and distance at which they were launched against the implant [14]. According to De Groot et al. [17], hydroxyapatite plasma spray implants have already been studied and considered to have a high potential for osseointegration. Other authors showed that titanium implants coated with plasma spray of hydroxyapatite had greater amounts of bone at the bone/implant interface when compared to implants with smooth surface [18, 19].

#### *2.1.3 Laser surface treatment*

In this type of surface treatment, the implant's surface is modified by irradiation by means of laser beams, producing erosions and a rough surface. It is considered a clean treatment as it does not interact with any external material during the surface modification process, in which the laser beam acts as a physical means in the treatment of this surface [15]. Studies have shown that this method can stimulate adequate osseointegration to implants [20, 21]. In addition, laser treatment has the advantage that oriented, regular micro-grooves with different depths can be created at defined points on the surface [14]. Roughness sizes depend on the pulse intensity of the emitting source [9]. This type of surface has been extensively studied by Ricci et al. [22], showing that micro sulci can modulate cell organization and, consequently, positively influence the osseointegration process.

#### *2.1.4 Surface blasting by micro particles*

This type of treatment for the implant surface is blasting with microparticles of some abrasive material (e.g., aluminum oxide or titanium oxide), which promotes irregular surface depressions. Ideally, there should be no adhesion of particles to the implant (residues), which should be removed during the cleaning and decontamination processes. Obviously, the roughness caused depends on the size of the microparticles used, the time and pressure used in the process [9, 14, 15, 21]. In **Figure 4** it is possible to observe the result of the treatment of a surface using only the sandblasting with aluminum oxide particles. However, the roughness produced has sharp edges and several non-uniform irregularities, which can make contact and cell organization difficult and,

consequently, have an opposite effect to what is expected for an adequate osseointegration. Currently, this type of isolated treatment is little used by the industry.

Moreover, SEM (scanning electron microscopy) analysis of implants subjected to microparticle blasting, in this case aluminum oxide (Al2O3), show residues from the manufacturing process that can contaminate the implant surface (**Figure 5**), which would be harmful to osseointegration, as they would compete with calcium for bone formation. On the other hand, the use of titanium oxide in place of alumina can be an alternative to avoid these undesirable effects on the implant surface [23–25].

In this sense, Gehrke and Collaborators, comparing implants blasted with aluminum oxide and titanium oxide, demonstrated that the residual particles from blasting can interfere in the osseointegration process in these places where they are present [23]. Moreover, in other studies using in vitro and in vivo tests, were demonstrated an excellent biologic response of the surfaces treated by sandblasting with microparticles of titanium oxide [24], with minimal risk of contamination by the residual debris from the blasting procedure [25].

**Figure 4.**

*SEM images of a surface treated by sandblasting with aluminum oxide, where we can observe in higher magnifications the presence of sharp edges and other deformations resulting from this surface treatment process.*

#### **Figure 5.**

*SEM image showing some locations, among several in the same sample, with the presence of residual microparticles on a blast-treated surface. This surface continued to show the presence of residues even after the washing and decontamination process.*

*Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

#### *2.1.5 Surface blast treatment followed by acid etching*

As described above, the sandblasting process, which can be done by different particles (e.g., aluminum oxide or titanium oxide) and different sizes (150–500 μm), creates deep, amorphous roughness and can leave sharp edges sharp on the surface of the implants. Therefore, acid etching was used after the blasting process, leaving a much more regular surface, and eliminating (rounding) the peaks left by the first process. This union between the 2 types of treatment was called and patented as SLA surface (Sandblasted, large grit, acid-etched implant surface) by the Straumann Company. For the treatment of SLA Straumann surface implants, blasting with coarse-grained aluminum oxide (250–500 μm) is initially performed, producing macro-roughness in the implant, followed by an acid etching (HCl/H2SO4), which is responsible for the microroughness on this surface [6]. However, this treatment model is used by several companies, with variation both in the blasting process and in the acid etching process.

In this sense, comparing 2 different models of implant surface blasting with aluminum oxide and titanium oxide and subsequent etching by different acids in scanning microscopy images, we can observe that the texture of the surfaces has a different morphology between them, as shown in images in **Figure 6.**

To accelerate and improve the osseointegration process of this type of SLA surface, the processing means were modified, being made under nitrogen atmosphere and later stored in isotonic NaCl (sodium chloride), this surface being called SLActive. Thus, these implants could provide a more active osseointegration process than other implants [26] and, consequently, could be loaded with a reduced waiting time. In this new technique, the surface is hydroxylated, and this chemical change improves the surface structures, which are ideal for protein adsorption and to promote immediate implant intent into bone tissue. The SLActive surface was developed to optimize implant stability in less time and reduce treatment risks in the early stages [27]. Rupp et al. [27], demonstrated that the SLActive and SLA surfaces did not show apparent differences when both had the same topography, however, statistically significant differences were observed within two or four weeks of BIC repair (bone/implant contact). This demonstrates that the changes were not a consequence of the topography, but that they were probably due to changes in the chemical structures made on the surface. Oates et al. [28] demonstrated that accelerated bone formation can influence

#### **Figure 6.**

*Images obtained by SEM at 100x magnification, showing 2 different models of implant surface sandblasting: (a) with aluminum oxide and (b) with titanium oxide. Both received further conditioning by different acids. We can observe that the surface texture has a different morphology between them.*

**Figure 7.**

*SEM images at different magnifications of an acid-etched implant surface.*

implant stability. Also, in that same study, the authors observed that the transition time from primary stability to secondary stability was two weeks for SLActive surface and four weeks for SLA.

#### *2.1.6 Acid conditioning treatment*

The surface treatment by conditioning through acids is made by immersing the implant in an acidic substance, which causes erosion on this surface. Acid concentration, time and temperature are determining factors of the surface microstructure. On the smooth surface, the most used process is the double acid attack, carried out with sulfuric acid and hydrochloride [29]. This surface treatment process provides a very uniform morphology, however, with less depth of ripple compared to SLA-type surfaces. An advantage of this type of treatment is that it supposedly does not leave residues of contaminants in your process. In **Figure 7** we can see an implant surface treated by acid etching.

#### *2.1.7 Anodized surfaces*

In the case of nanotextured surfaces, treated with anodizing, they receive an extra layer of titanium dioxide. Thus, these surfaces are obtained using the implant as an anode, activating ions, and applying an electrical potential, which generates charge and ion transfer reactions. Controlled, the electric field will guide the oxidation process that takes place on the implant and results in an increase in the thickness of the titanium oxide (TiO2) layer. With the increase of this titanium oxide layer and the addition of other elements, such as phosphate (PO4), there is a potentialization of osseointegration [9].

Corrosion resistance and biocompatibility are related to the presence of a nonreactive oxide layer, which prevents the formation of fibrous tissue around the implant and creates a direct contact with the bone tissue [21, 27]. Implants with this surface treatment are less dependent on chemical composition, as the resulting process is defined by a complementary increase in bone-implant contact [30]. This type of surface treatment has become well known in the implantology field for being used in implants from the Nobel Biocare company (Sweden). **Figure 8** shows images obtained by SEM of the surface of an anodized implant.

#### *2.1.8 Biomimetic surfaces*

Abe et al. [31], presented a procedure that allowed to cover the implant surface with a uniform layer of HA similar to the biological layer, up to 15 μm thick, called the biomimetic method. This type of surface treatment consists of the heterogeneous *Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

**Figure 8.**

*SEM images with different magnifications of an implant surface treated by the anodized method.*

precipitation of calcium phosphate under physiological conditions of temperature and pH on the dental implant, using a solution of ions similar to blood plasma with a view to deposition of the apatite layer. Once the molecules are integrated into the material structure, they are gradually released, thus being able to increase bone conductivity and enhance bone formation around the implant [32]. Currently, calcium phosphate is one of the main biomaterials for bone tissue replacement and regeneration, as its main characteristics are similar to the mineral phase of bone tissue, excellent biocompatibility, bioactivity, absence of toxicity, degradation rates variables and osteoconductivity [32]. Another advantage of this surface treatment is that biologically active molecules, such as osteogenic agents, can be precipitated as inorganic components to form a matrix with both osteoinductive (growth factors) and osteoconductive (calcium phosphate layer) properties [21, 27]. **Figure 9** shows SEM images of an implant surface treated by the biomimetic method.

Studies on this type of surface have shown greater contact between bone and implant on surfaces with biomimetic calcium phosphate coatings than on untreated surfaces [21]. Huang et al. [33], investigated the effects of chemical and nanotopographic modifications in the initial stages of osseointegration, and the results showed a greater removal torque and greater bone apposition for implants with chemical nanotopographic modifications. Recently, we presented in a study of adhesion, cell growth and in vitro mineralization using a surface with deposition of hydroxyapatite nanoparticles showed a superior result to the control group [23]. Furthermore, our group studied the deposition of calcium–magnesium on the surface of implants, where an acceleration and improvement in the osseointegration of implants inserted in rabbit tibiae was observed histomorphometrically, compared to implants with surface treated by blasting with titanium oxide and conditioning acid.

#### **Figure 9.**

*SEM images at different magnifications showing an implant surface treated by the biomimetic method.*

In conclusion, we can say that the main results of surface treatments with the aim of improving osseointegration were to accelerate the osseointegration time, allowing the anticipated loading of implants. On the other hand, osseointegration occurs on the surfaces of dental implants, regardless of whether these are treated or not. Surface treatments improve the result of osseointegration, especially in the initial stages, benefiting a bone apposition with qualitative and quantitative density. Despite the results presented, the dental literature is not unanimous as to the best type of surface treatment.

### **2.2 Implant body shape**

Bone density and quality, surgical technique and implant body geometry are factors to be considered to obtain a shorter period of osseointegration, thus enabling a reduction in treatment time [34]. The relationship between these factors will determine the initial stability of the implant, defined as the absence of movement after its surgical insertion [35–38]. According to some studies [34, 39, 40], the success of implants is dependent on the initial stability achieved, as this is a prerequisite for bone cell differentiation and osseointegration [41]. The shape of the implant has been one of the most contested variables among engineers and researchers, as it can directly influence the biomechanics of the implant inserted into bone tissue [42].

Regarding the implant body shapes most frequently found on the world market, we have cylindrical, semi-tapered and tapered implants, as shown schematically in **Figure 10**. Currently, most implant manufacturing companies use the last two implant designs mentioned above (semi-tapered or tapered). Initially, tapered implant designs were introduced in implant dentistry with the main advantage of producing better initial stability compared to cylindrical implants. Later, several studies were developed and published comparing the tapered with the cylindrical implant designs [43–45]. Recently, new discoveries about the advantages of these designs were observed, such as and, mainly, the lesser surgical trauma during the drilling procedures and insertion of these implants in the bone tissue [46].

Other authors have shown that the use of implants with a conical design can increase stability in low-density bone, since results demonstrated greater contact osteogenesis with this type of design [45]. However, the difference in this stability between implants with different designs has not been sufficiently investigated, with

#### **Figure 10.**

*Representative images of 3 implant designs: (a) cylindrical implant, (b) semi-tapered implant and (c) tapered implant.*

*Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

disagreements about the fact that the tapered implant shows higher values of initial stability when compared to the cylindrical implant [47] or not cylindrical [48].

For years, companies have sought to commercialize the tapered shape in order to combine the advantages of the two designs, considering that a tapered implant creates a basis for adequate primary stability, by allowing the gradual expansion of thin bone crests and determining a minimum of possible stress at the interface with the surrounding bone [49]. In addition, tapered implants can be used in different clinical situations, being installed with less damage to the bone bed, but their installation in the lower arch has not been widespread, as it is strongly recommended for areas with low density bone or bone beds after dental extractions [50].

#### **2.3 Shape of the implant threads**

During the last decades, different implant macrogeometries have been proposed and marketed, with variation in different points, such as body design, cervical and apical design, threads design, among others. As for the thread design, these can be found with square, V-shaped, trapezoidal and inverted trapezoidal shapes [45]. **Figure 11** demonstrates different implant coil designs presented and marketed by different implant companies.

For some authors, implants with narrow pattern threads increase the surface area, leading to a more favorable stress distribution, and achieving higher primary stability values [51, 52]. In addition, stresses are more sensitive to thread pitch in cancellous bone than in cortical bone [53]. However, considering that the ideal implant should provide a balance between compression and traction forces, minimizing the generation of shear force, the square shape was designed to reduce such force at the bone-interface. Implant and increase the stability of the implant [53]. Thread depth, thickness, angle, end and helical angle are some of the various geometric patterns that determine the functional surface of the thread and affect the distribution of biomechanical loads on implants [7].

**Figure 11.** *Images of different designs of implant threads produced and marketed.*

Transforming shear forces into resistance forces at the bone interface is the proposal to incorporate threads into the body of implants [54, 55]. This is why most implants are currently threaded, as non-threaded implants essentially result in shear forces at the bone-implant interface [26, 56–58]. Kohn et al. [59], demonstrated that the tension is more concentrated in the area of contact between the bone and the crest of the thread and that this tension decreases from the crest to its most basal portion. It has been proposed that threads, due to their shapes, would generate heterogeneous stress fields within the "physiological overload zone", thus promoting new bone formation [60], which would justify the formation of bone in intimate contact with the crest of the threads. However, it should be noted that the threads have different shapes, therefore different distributions of forces and biological responses, which will be discussed below.

The functional surface area per unit of implant length can be modified by varying 3 parameters of the thread geometry: pitch, shape and depth [61]. The shape of the thread is a very important feature of its general geometry. The shape of the thread can change the direction of occlusal loading of the prosthesis to different directions in the bone. Under axial loads, a triangular thread is comparable to a trapezoidal thread when the face angles are similar, which are usually 30 degrees [62]. It has been suggested that a square thread design reduces the shear force component, transferring the axial force that falls on the prosthesis to the implant body in a more axial fashion, favoring bone compression [63]. This would be particularly important for the bone crest region, where, according to Lum [64], most occlusal forces are distributed. Therefore, implant design considerations that reduce the development of shear forces at the bone-implant interface can improve long-term success, particularly in low-density bones [65]. The original Bränemark implant, introduced in 1965, had triangular threads, to be installed in place with threaded osteotomy16. The initial design has been modified over the years to allow for a simpler and more efficient installation, as well as a better distribution of loads. Albrektsson et al. [66], recommend that the top of the threads be rounded to relieve stress concentration.

The thread pitch is defined as the number of threads per unit of length in the same axial plane and on the same side of the axis of the implant body [61]. The smaller the pitch, the greater the number of threads in the implant body, and therefore the greater surface area. So, if the magnitude of force is increased or bone density is reduced, the thread pitch can be reduced to increase the functional surface area, thus improving the stress distribution. Ease of surgical insertion is also associated with the number of threads. The smaller the number of threads, the easier the implant insertion. In denser bones, however, a smaller number of threads is more favorable, since the hard bone offers greater resistance during insertion of a threaded implant [61]. Another important factor to be discussed is the difference between the final milling dimension proposed by the manufacturer and the implant body. Usually, the dimension of the last reamer used for the osteotomy corresponds to the diameter of the implant body. Thus, the deeper the turns, the greater this difference will be, causing a greater insertion of the implant (threads) into the bone tissue. **Figure 12** schematically shows the difference between the cutter and the implant in two different thread models.

Other concept is the "double-thread" and "triple-thread" implants has been recently introduced [63]. These implants have been associated with faster threading in the surgical alveolus and with an increase in primary stability, as they require a higher insertion torque, and are indicated for cases of low density bone [67]. However, the number of threads, their depth and the total surface area are exactly the same regardless of the number of threads, whether single, double or triple.

*Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

**Figure 12.**

*Schematic images of the difference between the final reamer used for the osteotomy of each implant model and the thread depth that would be introduced into the bone tissue.*

Instead of using a single instrument to make a 0.6 mm thread for each turn on the device, 2 or 3 instruments make 2 or 3 turns at the same time. These 2 or 3 devices are independent, starting 180° apart from each other and are also 0.6 mm threaded apart. In other words, a single thread contours the implant body 0.6 mm apart and the double thread 1.2 mm apart, on the same surface area. This technique allows installation of the implant in half the time [63].

The triangular thread shape has a 10 times greater shear over the bone than a square thread and is similar to the trapezoidal thread [61]. Square threads have an optimized surface area, which is great for transmitting intrusive and compressive loads, resulting in less bone tension. Trapezoidal threads are optimized to resist tensile loads [68]. Implants with reverse trapezoidal threads have fewer and shallower threads [63].

Another advance in the shape of threads has been the introduction of round shapes, which are said to induce osseocompression [63]. A round-shaped design has shown, in histological observations in animals, the formation of lamellar bone by osseocompression [69]. This allows the bone to be shaped and compacted circumferentially.

Thread depth refers to the distance between the largest and smallest diameter of the thread. Traditional implants offer a uniform thread depth, however this can be varied along the length of the implant in order to provide a functional surface area in the most intense stress regions (such as the alveolar bone crest region) [61]. Regarding the quality and percentage of osseointegration, Steigenga et al. [70], analyzed the effect of 3 types of threads (triangular, square and trapezoidal) through histomorphometric and reverse torque analyses. They found a significantly higher reverse feel and percentage of bone-to-implant contact for implants with square threads. No significant difference was found between the tests for implants with triangular and trapezoidal threads, corroborating the results of other studies with different methodologies [61, 62, 70]. It should be considered that the different

shapes of the threads cause different distributions of forces and biological responses [56, 57, 59, 60, 62, 71, 72].

#### **2.4 New implant macrogeometries**

Modifications in the morphology and roughness of the implant surface were initially attempted not only to accelerate the host's response to the implant, but also to increase the level of mechanical locking between the bone and the implant surface, thus improving initial stability and subsequent dissipation loads during the functional requirements of the system [72]. Numerous studies based on histological tests have shown that surface texturing, created by different processes, leads to greater contact between bone and implant compared to the machined surface [6, 10, 73], which is a desirable answer to improve the overall biomechanics of the system, as show in the Section 2.1 of the present chapter. However, recently, new implant designs have been developed that seek, mainly, to accelerate and improve the quality of osseointegration through the concept of decreasing bone tissue compression during implant installation.

In most implant systems, osteotomy is recommended using the last drill with a diameter slightly smaller than the diameter of the implant, so that it can be inserted with a high degree of torque. Obviously, the more undersized the site that will receive the implant, the greater the insertion torque. However, studies have shown that high levels of torque can cause high compression of bone tissue, which can lead to extensive bone remodeling over time [74]. Several other studies have shown that, depending on the implant insertion torque and the physiological tolerance limit, microfractures or compression osteonecrosis may occur [75–77].

In this sense, it was recently proposed in some studies that approximating the osteotomy diameter with the diameter of the implant that will be implanted can facilitate and improve osseointegration [77, 78]. This fact was demonstrated in other animal studies, in which implants that were installed with high torque had a certain amount of necrotic bone inside the threads of the implants, while in samples where a perforation with a diameter closer to the diameter of the implant, greater new bone formation [78]. In this case, the free space created within the implant threads, resulting from the diameter-drill-implant relationship, was called healing chambers (**Figure 13**).

#### **Figure 13.**

*Schematic images of the relationship between the osteotomy (blue lines) and the implant diameter inserted. In the left image the regular osteotomy and in the right image the oversized osteotomy generating the healing chambers.*

## *Characteristics of Implant Systems That Can Accelerate and Improve the Osseointegration Process DOI: http://dx.doi.org/10.5772/intechopen.99937*

In order to reduce the compression during insertion of the implant into bone tissue, two new implant models were recently launched on the world market, the BLX Straumann model (Basel, Switzerland) and the Maestro Implacil De Bortoli model (São Paulo, Brazil), that are presented in the **Figure 14**.

The first model (BLX Straumann implant) has technical recommendations to avoid bone compression, that during the execution of movements for insertion, whenever the torque of 35 N is reached, the professional must perform anti-rotational turns movements (removal torque) and then go back to inserting, repeating this movement whenever necessary. Thus, with a torque value below 35 N, bone tissue compression would be low, facilitating the osseointegration process. While in the second model described (Maestro Implacil implant), healing chambers were created in the implant body, which consist of small circular cavities 0.2 mm deep by 0.5 mm in diameter, as shown in **Figure 15**. With the presence of these healing chambers, bone tissue decompression occurs automatically during its insertion, not

#### **Figure 14.**

*Image of both implant models recently launched on the world market that were developed to reduce bone compression during the insertion process.*

#### **Figure 15.**

*SEM image of the healing chambers that were created in the implant body, which consist of small circular cavities 0.2 mm deep by 0.5 mm in diameter.*

requiring any additional maneuvers. As reported in our studies of this new implant macrogeometries, this implant model has a reduced insertion torque compared to the model that does not feature healing chambers but did not show lower initial stability values measured by resonance frequency [12, 79–81].


1. Introduction

Nowadays, cargo transportation plays an important role in many industrial fields. For carrying the cargo in short distance or small area, such as in automotive factories and shipyards, the overhead cranes are naturally applied. To increase productivity, the overhead cranes today are required in high-speed operation. However, the fast motion of overhead cranes usually leads to the large swings of cargo and non-precise movements of trolley and bridge. The faster the cargo transport is, the larger the cargo swings. This makes dangerous and unsafe situation during the operating process. The crane itself and the concerning equipment in the factory can be damaged without proper control strategies.

In recent decades, the control problems of overhead cranes in both theory and practice have attracted many researchers. Various kinds of crane control techniques have been applied from classical methods such as linear control [1], nonlinear control [2, 5, 6], optimal approach [7], adaptive algorithms [8, 9] to modern techniques such as fuzzy logic [3, 4, 10], neural network [11], command shaping [12], and so on.

© The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, © 2018 The Author(s). Licensee InTech. 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, provided the original work is properly cited.

distribution, and eproduction in any medium, provided the original work is properly cited.

The abovementioned researches deal with crane motion modeled as pendulum or multisection pendulum systems. As a result, their dynamics are described as an ordinary differential equation or a system of ordinary differential equations. In practice, the crane rope exhibits a certain degree of flexibility; hence, the equation of motions of the gantry crane with flexible rope is represented by a set of partial differential and ordinary differential equations. In [13– 15], the authors successfully design a controller that can stabilize the system with the rope flexibility. Flexible rope also is considered in [16, 17] where coupled longitudinal-transverse motion and 3D model are investigated.

This chapter accesses the modeling and control of overhead cranes according to the other research direction. We construct a distributed model of overhead cranes in which the mass and the flexibility of payload suspending cable are fully taken into account. We utilize the analytical mechanics including Hamilton principle for constructing such the mathematical model. With the received model, we analyze and design two nonlinear control algorithms based on two versions of Lyapunov stability: one is the so-called traditional Lyapunov function and the other is the socalled barrier Lyapunov. Dissimilar to the preceding study [18, 19] whereas the problem of actuated payload positioning system is considered, the proposed controllers track the trolley to destination precisely while keeping the payload swing small during the transport process and absolutely suppressed at the payload destination with control forces exerted at the trolley end of the system. The quality of control system is investigated by numerical simulation. Since the system dynamics is characterized by a distributed mass model, the finite difference method is applied to simulate the system responses in MATLAB® environment.

The chapter content is structured as follows. Section 2 constructs a distributed mass model of overhead cranes. Section 3 analyzes and designs two nonlinear controllers based on Lyapunov direct theory. The analysis of system stability is included. Section 4 numerically simulates the system responses and analyzes the received results. Finally, the remarks and conclusions are shown in Section 5.


*4.2. Cartilage Tissue*

Cartilage in adult animals is a connective, smooth, and resilient tissue. Hyaline cartilage is avascular, and it is present in the stress points of skeletal tissue, such as bone heads, where it provides flexibility and prevents abrasion and damage [77]. It is also present in the rib cage, nose, larynx, and trachea, while its extracellular matrix is composed of collagens, mainly collagen type II, glycosaminoglycans (GAGs), and laminin [78]. GAGs are closely related to cartilage mechanical properties and help the tissue to cope with sudden external forces [24]. Elastic cartilage is a supportive structure for tissues such as the outer ear and epiglottis, and histologically, it is similar to hyaline cartilage, but with much more elastic fibers [21]. On the other hand, fibrocartilage is the only cartilage with collagen type I in its structure, because it is a mixture of fibrous tissue and cartilaginous tissue, with unique toughness and elasticity properties, and is present in intervertebral discs and menisci, among others.

Hyaline cartilage is the most commonly targeted cartilage in regenerative treatment—in particular, the one covering the end of bones in articulations. Damage to articular cartilage is usually related to trauma or pathology, and can cause pain, osteoarthritis, or even loss of functionality [78]. Surgical interventions attempt to solve these conditions, but at present, they are largely temporary solutions, pushing research toward searching for new regenerative approaches. The lack of vascularization greatly limits the number of nutrients and oxygen that can reach the inner parts of the tissue. This condition makes cartilage regrowth particularly challenging [79]. Therefore, tackling articular cartilage regeneration is a challenging goal. The literature is extensive in terms of approaches aiming to regenerate articular cartilage tissue, using di fferent kinds of implantable sca ffolds [80,81]. In this sense, cartilage dECM derivatives have been used for coating other implantable materials or as a 3D-printed structure for knee and meniscal regeneration, among others.

The basics for articular cartilage decellularization are the same for the di fferent types of cartilages, and in general, decellularization aims to keep in the matrix as many GAGs as possible. Of note, as the di fferent cartilages have di fferent permeability properties, it is paramount to set up proper conditions for optimum decellularization in each case.

Tissue snap freezing or freeze–thawing is a common pretreatment in many decellularization protocols [24,58]. Similarly, pretreatment with hypotonic and hypertonic solutions is also a popular method, used to induce apoptosis by osmotic pressure [11]. These methods do not decellularize the structure by itself, but they help further decellularization methods to work better and to reach the inner parts of the tissue. It has been proved that snap freezing does not a ffect the matrix component, and it has no significant negative impact on the structure [82]. Conversely, initial tissue homogenization, suggested in some articles, leads to the significant loss of GAGs and structural proteins [83].

Further to physical pretreatments, decellularization has been assayed with enzymatic or chemical detergent methods. The enzyme trypsin–EDTA is the most common decellularization approach reported [83]. Trypsin–EDTA breaks both the proteins that hold the cell in place inside the matrix, as well as the cell membrane proteins. Based on protease activity, the main setback of using this technique is the degradation of the proteins of potential interest in the final dECM. In order to prevent this, the exposure time to trypsin–EDTA needs to be highly controlled, and it is usually limited to 6–24 h [51].

Regarding the detergents used as decellularization reagents, Triton X-100 and SDS are the most commonly used ones. Both cause some extent of damage to the structure of the matrix, but the mechanical integrity of the matrix maintains at an acceptable level. Note that both incur damage to GAG content and integrity, being Triton X-100 the worse in this sense [26,45].

An additional issue to be taken into account regarding cartilage tissue is the need for enzymatic treatment with nuclease activity to prevent waste nucleic acid material from sticking to the matrix [11]. In elastic cartilage, the nuclease time may be necessarily longer to ensure decellularization. In articular cartilage, on the other hand, being a less dense structure, the risk of having DNA material stick to the protein matrix is lower.

The digestion of GAGs using chondroitinase ABC (ChABC) has been reported as a cartilage decellularization method. It is not a commonly used technique; although it facilitates the removal of native chondrocytes, it reduces the mechanical properties of the tissue as well [11].