**Chapter 3**

*Hormone Therapy and Replacement in Cancer and Aging-Related Diseases*

[62] Zhou Q, Shen L, Liu C, Liu C, Chen H, Liu J. The effects of estradiol and glucocorticoid on human osteosarcoma cells: Similarities and differences. Anticancer Research. 2016;**36**:1683-1691

BAX/BCL-2 and reducing pERK1/2. Anticancer Research. 2012;**32**:1181-1191

[56] Wang W, Belosay A, Yang X, Hartman JA, Song H, Iwaniec UT, et al. Effects of letrozole on breast cancer micro-metastatic tumor growth in bone and lung in mice inoculated with murine 4T1 cells. Clinical & Experimental Metastasis. 2016;**33**:475-485. DOI: 10.1007/s10585-016-9792-z

[57] Ariazi EA, Leitao A, Oprea TI, Chen B, Louis T, Bertucci AM, et al. Exemestane's 17-hydroxylated metabolite exerts biological effects as an androgen. Molecular Cancer Therapeutics. 2007;**6**:2817-2827. DOI: 10.1158/1535-7163.mct-07-0312

[58] Bartels S, Christgen M, Luft A, Persing S, Jödecke K, Lehmann U, et al. Estrogen receptor (ESR1) mutation in bone metastases from breast cancer. Modern Pathology. 2018;**31**:56-61. DOI:

[59] Kang E, Cho JH, Choi J-H, Yoo H-W. Etiology and therapeutic outcomes of children with gonadotropinindependent precocious puberty. Annals of Pediatric Endocrinology & Metabolism. 2016;**21**:136. DOI: 10.6065/

[60] Gorska M, Wyszkowska RM, Kuban-Jankowska A, Wozniak M. Impact of apparent antagonism of estrogen receptor β by

fulvestrant on anticancer activity of 2-methoxyestradiol. Anticancer Research [Internet]. 2016;**36**:2217-2226. Available from: http://www.ncbi.nlm.

[61] Holen I, Walker M, Nutter F, Fowles A, Evans CA, Eaton CL, et al. Oestrogen receptor positive breast cancer metastasis to bone: inhibition by targeting the bone microenvironment in vivo. Clinical & Experimental Metastasis. 2016;**33**:211-224. DOI: 10.1007/s10585-015-9770-x

nih.gov/pubmed/27127126

10.1038/modpathol.2017.95

apem.2<IP_ADDRESS>

**34**


Preface

Chapter 7 **Neuromusculoskeletal Rehabilitation of Severe**

Balakrishnan and Amruta Kulkarni

Deepak Sharan, Joshua Samuel Rajkumar, Rajarajeshwari

Alejandro Rafael Garcia Ramirez, Cleiton Eduardo Saturno, Mauro José Conte, Jéferson Fernandes da Silva, Mísia Farhat, Fabiana de Melo Giacomini Garcez Garcez, Ana Carolina Savall and Elaine

Chapter 8 **Assistive and Adaptive Technology in Cerebral Palsy 173**

**Cerebral Palsy 141**

**VI** Contents

Carmelita Piucco

Cerebral palsy (CP), the most common cause of physical disability in children, is a nonprog‐ ressive neurological impairment that is a result of an injury in the developing brain and it causes various neuromuscular and cognitive disabilities. CP is often accompanied by other disturbances of sensation, cognition, communication, perception, and behavior and seizure problems. It also leads to multiple problems that affect functionality and psychosocial health of children and adolescents, so they are unable to play important roles in their family, school, and other environments. Thus, rehabilitation aims to improve functional health sta‐ tus and increase independence in daily life, school, and social environment, which are very crucial for the CP treatment. Rehabilitation of the child with CP is difficult, often frustrating, and sometimes depressing. This is even more pronounced in countries with limited resour‐ ces for the handicapped. An interdisciplinary management approach is the only means to integrate children with CP.

I would like to thank our book company InTech and all authors. I am indebted to Ms. An‐ drea Korić for helping us with text editing of this book.

I hope readers will benefit from our book and they will use this book in their treatment and clinical decision.

#### **Mintaze Kerem Gunel, PT, PhD, Prof.**

Hacettepe University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Cerebral Palsy and pediatric Physiotherapy Unit, Ankara, Turkey

**Definition, Epidemiology and Etiological Factors of Cerebral Palsy**


*2.1.1. Electrophoretic deposition*

This is the most favored method due to several reasons, which include effectiveness in the fabrication of coatings and films from suspensions [14], a short period of time is required for deposition, the ability to deposit a film on a non-uniform surface, it is cost effective, it is easy to control the thickness of the films, ability to utilize suspensions of low solids loadings, homogeneity of resultant coatings, simple apparatus requirements, binder-free process and it is possible to prepare homogeneous coated layers or deposited films [15, 16].

The process involves the movement of charged particles in a suspension medium followed by deposition on a substrate under an applied DC voltage [17, 18] as shown in **Figure 2**. When the voltage is applied to the electrodes, an electric field is created that interacts with the surface charge of the nanoparticles, producing a force that makes the particle move toward the electrode of the opposite charge and their accumulation on this electrode leads to the formation of a homogeneous layer.

Different thickness of the films can be achieved by changing the deposition parameters such as voltage, deposition time, solvent type, zeta potential particle and loading in the suspension [17]. Some researchers have used different combinations in titanium dioxide thin film

**Figure 2.** Schematic setup of the electrophoretic deposition cell [16].

deposition for different applications such as biomedical applications [19], ceramic coatings [20] and dye-sensitized solar cells [21–23]. Nyongesa and Aduda used electrophoretic deposition technique to deposit titanium dioxide thin films on conducting glass substrates for application in water purification [16]. In the study, they found out that ethanol was a better solvent to use compared to toluene, propanol or water, which they believed was due to its high dielectric constant (ε) of 24.3. Water is not a suitable suspension medium due to water electrolysis which takes place during the deposition and this can cause gas bubbles to accumulate at the electrode surfaces, which is detrimental to the electrophoretically deposited coating. The best parameters for good adherence of the nanoparticles were: pH value of 3, solid loading of 4.0 wt% and a voltage of 20 V [16]. In a similar study by Nguu et al. [24], to achieve a uniform film of 5 μm, the best voltage and time were 35 V and 90 s, respectively, and they discovered that extended deposition times (>90.0 s) resulted in formation of agglomeration [24]. In another study by Dhiflaoui et al., it was found that the coatings deposited at 20 V for 4 min were the most homogeneous [25]. They also discovered that transformation of anatase to rutile depends on the electric current in the electrochemical cell. When the voltage is increased, the modulus of elasticity and hardness of the films also increase.


**CORROSION INHIBITORS, PRINCIPLES AND RECENT APPLICATIONS**

Edited by **Mahmood Aliofkhazraei**

#### **Corrosion Inhibitors, Principles and Recent Applications**

http://dx.doi.org/10.5772/intechopen.70101 Edited by Mahmood Aliofkhazraei

#### **Contributors**

Shimaa Ali, Khadijah Emran, Hamedh Al Lehaibi, Ojo Sunday Fayomi, Aa Daniyan, Api Popoola, Saraswathy V, Han Seung Lee, Seung Jun Kwon, Subbiah Karthick, Jorge Morales-Hernandez, Araceli Mandujano Ruiz, Luis-Enrique Corona Almazán, Héctor Herrera Hernández, Daniel Véras Ribeiro, Marianna Rivetti, José Andrade Neto, Nilson Amorim Júnior, Bogumil E. Brycki, Iwona Kowalczyk, Olga Kaczerewska, Adrianna Szulc, Marta Pakiet, Omnia Shehata, Adel Attia, Lobna Korshed, Michael Schorr, Benjamin Valdez, Juan Ricardo Salinas, Nelson Cheng, Yuli Yetri, Gunawarman -, Emriadi -, Novesar J, Amornvadee Veawab, Adisorn Aroonwilas, Sureshkumar Srinivasan, Norinsan Kamil Othman, Zulhusni Dasuki, Emee Marina Salleh, Mohamad Azwani Shah Mat Lazim

#### **© The Editor(s) and the Author(s) 2018**

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First published in Croatia, 2018 by INTECH d.o.o. eBook (PDF) Published by IN TECH d.o.o. Place and year of publication of eBook (PDF): Rijeka, 2019. IntechOpen is the global imprint of IN TECH d.o.o. Printed in Croatia

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*Moisture and Solid Mass as Indicators of the Ideal Transformation Technology DOI: http://dx.doi.org/10.5772/intechopen.112272*


*3.4. Anti-Infective Nanobiomaterials*

Disease, injury, and trauma can lead to serious bacterial infections, which cause disease and adverse complications in host tissues and even death of patients [523]. Nanobiomaterials made from polymers, metals, and ceramics might be a potential source of infection when they are introduced into the body [524,525]. Virus and bacterial infections cause unregulated damage that leads to organ failure [526]. In polymeric biomaterials, the most common bacterial infections are powered by *Staphylococcus epidermidis (S. epidermidis)* from skin and *Staphylococcus aureus (S. aureus)*, which may identified on metallic biomaterials [527]. Ceramics and metals can represent an alternative because of their resistance to infection. However, in presence of minor imperfections on the surface or microfractures, pathogens, such as bacteria, can form a colony [528]. Biomaterials from natural sources were used as alternative as scaffolds for promoting regeneration but they carry a risk for pathogenic transmission [529].


**14. On the hindsight objection and the problems with risk management**

Before departing from this topic, we must address an objection commonly brought forth, which in the designation of the author may be labeled, the 'Hindsight Objection'. The following is the 'Hindsight Objection'. There are always warnings of disasters and they are commonly ignored. When no disaster occurs, these warnings are forgotten. If one went back to every successful venture; e.g. a space flight, one would find the ignored warnings. Therefore, if one infers from warnings that an unsuccessful flight occurred, one is inferring from unwarranted premises. Whenever one goes back and traces the causes of disasters to unheeded warnings, one is justifying warnings through hindsight which is always 20-20. Hence, the label, the Hindsight Objection.

There are two major replies to this objection. The first reply is that it is entirely hypothetical. In order to make good on the Hindsight Objection, one must bring forth evidence to support it. In other words, one must take a successful venture; e.g., a space flight, and show first of all that there were red-flagged warnings that the flight should not have taken place. If the 'red-flagged' designator is not in use, the warnings must be shown to be of high-priority status, i.e., it should be demonstrated that such warnings were equivalent in status to the warnings not to launch disastrous flights, such as the dire warnings that were lodged in the attempt to stop the launch of the *Challenger*. Warnings must be vetted in terms of the criteria spelled out above, in terms of source, form and content. What is commonly brought forth as "hindsight evidence" in the case of the Challenger are operational parts which are designated as Criticality 1, of which there were many such on the Challenger which did not fail. A Criticality 1 designation indicates that the failure of such a part would result in the loss of the vehicle and human life. But a Criticality 1 designation is not equivalent to a redflagged warning that the part designated as Criticality 1 was likely to malfunction. One cannot point to parts with a Criticality 1 designation that did not fail as evidence that there were warnings that failure was imminent. A part with a Criticality 1 designation could, theoretically, be extremely safe. To count as a legitimate warning, there must be a specific, high priority (red-flagged) warning concerning the faulty design or operational capacity under certain weather conditions, etc., of a part which possesses a Criticality 1 designation.

35 *Cf*., Peter Lattman and Jenny Anderson, 'For 92nd St. Y, a Break from Wall Street Worry,' *NY Times*, November 29. 2011. In this article, this guarantee is offered by the hedge fund manager, John A. Paulson.

This first condition, the prior presence of red-flagged warnings that meet the above criteria in terms of source (knowledgeable expert witness), form (red-flagged), and content (spelling out the specific flaw in the part), to the best of my research and knowledge, have never been met. The Hindsight Objection is always made as a purely hypothetical objection without any evidence for its truth value ever put forth. In the case of space flights (this example is used because it is best known to the author), one must show that there were other launches in which the senior scientist issued repeated red-flagged alerts and all of the engineers and managers voting on the planned launch voted unanimously against the launch. Has anyone ever brought forth any evidence in support of the Hindsight Objection claim?

150 Risk Management – Current Issues and Challenges

Hence, the label, the Hindsight Objection.

on Wall Street that guarantees any loss of any client's investment up to four million US dollars.35 How does this company do this? While the author of this chapter cannot answer this question, it would be assumed that this company is sufficiently profitable such that it can make this guarantee. What is notable is not that it is capable of making this guarantee; what is notable is that it makes the guarantee. By making such a guarantee this company is making the statement that it regards the potential loss of its client's funds as completely unacceptable. This standard of ethics is apparently commercially viable. This is an example, not of practicing risk management in the context in which it is most commonly accepted (that of a fund manager),

but rather of practicing not taking risk in the first place (with other people's money).

**14. On the hindsight objection and the problems with risk management**

Before departing from this topic, we must address an objection commonly brought forth, which in the designation of the author may be labeled, the 'Hindsight Objection'. The following is the 'Hindsight Objection'. There are always warnings of disasters and they are commonly ignored. When no disaster occurs, these warnings are forgotten. If one went back to every successful venture; e.g. a space flight, one would find the ignored warnings. Therefore, if one infers from warnings that an unsuccessful flight occurred, one is inferring from unwarranted premises. Whenever one goes back and traces the causes of disasters to unheeded warnings, one is justifying warnings through hindsight which is always 20-20.

There are two major replies to this objection. The first reply is that it is entirely hypothetical. In order to make good on the Hindsight Objection, one must bring forth evidence to support it. In other words, one must take a successful venture; e.g., a space flight, and show first of all that there were red-flagged warnings that the flight should not have taken place. If the 'red-flagged' designator is not in use, the warnings must be shown to be of high-priority status, i.e., it should be demonstrated that such warnings were equivalent in status to the warnings not to launch disastrous flights, such as the dire warnings that were lodged in the attempt to stop the launch of the *Challenger*. Warnings must be vetted in terms of the criteria spelled out above, in terms of source, form and content. What is commonly brought forth as "hindsight evidence" in the case of the Challenger are operational parts which are designated as Criticality 1, of which there were many such on the Challenger which did not fail. A Criticality 1 designation indicates that the failure of such a part would result in the loss of the vehicle and human life. But a Criticality 1 designation is not equivalent to a redflagged warning that the part designated as Criticality 1 was likely to malfunction. One cannot point to parts with a Criticality 1 designation that did not fail as evidence that there were warnings that failure was imminent. A part with a Criticality 1 designation could, theoretically, be extremely safe. To count as a legitimate warning, there must be a specific, high priority (red-flagged) warning concerning the faulty design or operational capacity under certain weather conditions, etc., of a part which possesses a Criticality 1 designation.

35 *Cf*., Peter Lattman and Jenny Anderson, 'For 92nd St. Y, a Break from Wall Street Worry,' *NY Times*, November 29.

2011. In this article, this guarantee is offered by the hedge fund manager, John A. Paulson.

The second major objection is that even if one could offer an example of a flight which met the equivalent set of warnings that were issued in the case of the *Challenger*, one might miss the point that such warnings are not intended to be construed to be 100% reliable predictions concerning the particular flight in question. Such warnings are not meant to be on the level not of, if this flight will take place, but of when this flight, or a similar flight, takes place, such a likelihood of such a flight ending in disaster is a horrific eventuality. If the warnings are not justified on the basis of one flight, they might well be on the basis of the third or the seventh flight. When one leaves the auto mechanic's shop with faulty brakes, the service manager might warn the customer that the brakes may fail. If the brakes do not fail on the first hill, that does not mean that her or his warning was without value. They may fail on the ninth hill. Thus, even if one could find a case in which dire warnings that fit the above criteria were present and the flight or sail went without incident, that would not prove that all such flights were to be considered safe.

It is informative to reflect on the fact that Boisjoly's warnings cover both the likelihood of the possibility of the *incidence* of the occurrence of the horrific failure of the mission and the *consequence* of the death of the crew and passengers. Thus, both aspects of risk are covered: the possibility of the likelihood of the incidence and the gravity of the consequence. This example of risk taking fits both the criteria of the likelihood of the possibility of the incidence and the enormity of the consequences. Such risk taking is entirely incompetent and unconscionable. *That it need not be restricted in its eventual occurrence in this flight is evidenced by the fact that it was warned against eight years previous.* The resistance to launch on this flight was based on the fact that the weather conditions compounded the already existent risk. *The problem was that the case of the decision to launch the Challenger was an iconic case where it was thought that risk could be managed. In other words, to some extent, the very concept of risk management was at fault.* A better example of a safeguard would have been never to have installed this unsafe part in the first place. That would have been an example not of risk management, but rather of not taking risk in the first place. (After that fatal flight, one of the original designs that was originally rejected was chosen to be used). More obviously, *not launching in adverse weather conditions would be an example of not taking risk*. *Launching in dangerous weather conditions is an example of attempting to manage risk*. It comes under the thinking of, 'the weather is not good, but we can manage it'. It is not clear what this means. It seems to suggest the belief that 'the weather is not good, but we can chance it.' 'Risk management', when properly analyzed, seems to be equivalent to 'risk chancing' or gambling'. The eminent Nobel laureate physicist, Richard Feynman likened the decision to launch the *Challenger* space shuttle to playing Russian roulette. The proper way of

thinking would have been, 'the weather is not good; we are not going to *take* the risk'. *When we frame the decision to be taken in term of risk taking rather than risk managing, it is far more likely that we will act not to take the risk rather than to act to take the risk and then attempt, somehow, to "manage" it.*

On the Very Idea of Risk Management: Lessons from the Space Shuttle *Challenger* 153

The idea of "risk management" implies that risk must be present. We must ever guard against complacency. If we keep uppermost in mind that the preciousness of life is our highest priority, we will ensure that the presence of the possible incidence and the consequence of risk is kept at the lowest possible point. *If we change our language from the language of "risk management" which implies that somehow there must always be a risk present, and it is our task to manage it, to risk taking, we will be more alive to the ethical responsibility which is involved in taking risks with our own or other people's lives.* We will be more inclined to work sincerely to minimize

The notion of providing enough safety boats for half of the passengers (the model of the *Titanic*) fits perfectly into the concept of "managing risk". When we do this, we have performed some kind of cost-benefit analysis, or, to speak more strictly, some kind of probability-benefit analysis, and have reached a decision that by providing life boats for only half of the passengers we are fulfilling the responsibility of "managing risk". It is not clear how this decision was reached. Perhaps, it was reached by assuming that only half of the passengers would make it to the life boats, hence, by providing half of the needed boats,

In conclusion, if we use the language of risk taking, the provision of life boats for half of the passengers on board is still a case of *taking risk with half of our passengers' lives*. On the other hand, if we take the language of risk taking seriously and consider that human life is precious, we would not sail, that is, we would not take risk, unless there were enough life boats provided for 100% of the passengers. (If we rely upon life preservers, for example, those in ocean waters would only live for a few minutes because of the icy temperature of the sea).

*Everything in the area of risk management is a matter of ethics*. Do we value human life? What do we mean by the phrase 'acceptable risk'? Such a concept can only be tolerated if there are safety provisions that will fully protect and preserve life if the consequences of the risk taking threaten human life. Otherwise, there is no such concept as an 'acceptable risk'. Was the decision to provide life boats for only half of the passengers aboard commercial vessels based on past performance data? In the case of the *Titanic*, lifeboats for only half of the passengers were provided and, as a result, the lives of 1,523 men, women and children were lost.36 1,523 men, women and children were killed based on risk management. The *Titanic* disaster was in 1912. Now, 100 years later while the custom is to provide enough lifeboats for all passengers, the lifeboats are prepared with engines that will leave their occupants at

It is hoped that this introduction to the new idea of risk taking as opposed to risk management will create reflection and commitment to a greater ethical sensitivity when we consider how our decision making may affect other people's lives. Do we ever have a right to take decisions that risk other people's lives? If the message of this chapter is heard, then we do not ever have the right to risk other people's lives unless we provide full and adequate protection for the consequences of the risk that we are taking with other people's lives. If we change our language habits from commonly using the phrase 'risk management'

the possibility of risk and to reduce the effect of the consequences of risk.

we have "managed" the risk.

the risks of the high seas.

36 *Ibid*., p. 87.

It is therefore worthwhile to consider abandoning the concept of risk management and replacing it with the concept of risk taking. When one removes the euphemism of risk management and replaces it with risk taking, it becomes abundantly evident that it is actual human life with which one is taking risk.  *The very concept of risk management is itself too risky*. The seemingly objective social science language of 'risk management' is in reality a license to treat human life lightly.


**6. Conclusion**

Finite element magnetic is a method that can be used to facilitate an intricate work or may not even be completed by other methods. In this case, the field of magnetorheology is an example of a problem by using the finite element method solution. The magnetorheological device is a device that uses iron particle materials whose working principle is to change its rheological properties due to the influence of a magnetic field. This magnetic field gives rise to a magnetic flux density in the device whose magnitude can be determined by solving the finite element method. To find out the magnitude of the magnetic flux density value, some finite element method magnetics software can be used, such as FEMM and Ansoft Maxwell. The solution to these problems can be resolved with the existence of boundary conditions and initial setups that are following the procedure, such as the type of problem, the use of materials, and a clear design configuration. Thus, problems requiring the finite element method can be resolved with good accuracy. Problemsolving with the finite element method simulation is considered more accurate than other methods. In the case of magnetorheological devices, magnetic simulation with the finite element method is very helpful to achieve the research objectives.


**5. Treatment of eosinophilic granulomatosis with polyangiitis**

#### **5.1 Conventional therapeutic regimen**

Like other AAV, corticosteroids are the treatment's cornerstone for GEPA. Depending on the severity of the presentation, high-dose corticosteroids are oftenly *Current Treatment of ANCA Vasculitis DOI: http://dx.doi.org/10.5772/intechopen.110375*

initiated with pulses of methylprednisolone (15 mg/kg). It is recommended for a minimum period of 4 weeks followed by a taper. This helps to control asthma, general signs and hypereosinophilia [32]**.** Corticosteroids are prescribed alone or combined with an immunosuppressant after evaluation of the clinical presentation by the FFS.

#### **5.2 Therapeutic alternatives**

There have been very few randomized controlled trials conducted to date in EGPA. Rituximab is not yet validated as an alternative to cyclophosphamide in GEPA. Due to the rarity of this disease compared to other AAV, a small number of therapeutic trials have been reported in the literature with conflicting results. Some studies confirm the efficiency of this biomedicine especially in case of relapse [35–38] and particularly in patients with a positive vasculitis/anti-MPO profile [39]**.** Nevertheless, in addition to infectious complications, rituximab has been incriminated in the occurrence of severe bronchospasm secondary to a hypersensitivity reaction [39]**.**

Recently, interleukin-5 inhibitors have been introduced into the GEPA therapeutic regimen. Mepolizumab is a humanized monoclonal antibody against interleukin-5. It has been approved for use in severe eosinophilic asthma. In refractory forms of GEPA, it was effective in remission induction and maintenance due to its immunosuppressive properties [40, 41]. A recent international randomized, controlled and double-blind study compared the effect of mepolizumab versus placebo in refractory GEPA treated with corticosteroids combined or not with immunosuppressive treatment. Long-term remission of GEPA was noted in the group using mepolizumab [42]**.**

Anti-IgE drugs such as omalizumab have been used during severe allergic asthma. For GEPA, the results of the use of this biomedicine are variable and contradictory. As previously described, omalizumab has been incriminated as an unmasking factor for underlying vasculitis [43]**.** Other studies suggest its efficacy during GEPA especially for pulmonary relapses but also as a cortisone-sparing agent [44, 45]. In conclusion, further data are needed before omalizumab can be recommended or contraindicated in the treatment of GEPA [36]**.**

### **6. Treatment of microscopic polyangiitis**

Management of MPA is based on remission induction therapy and remission maintenance therapy. For non-renal forms with an FFS equal to zero, corticosteroids are used alone as a first-line treatment to induce remission. An immunosuppressant will be associated in case of non-response, relapse or dependence on corticosteroids

but also in case of extension to a systemic form with involvement of other organs (cardiac, renal, CNS …). However, high-dose corticosteroids associated with rituximab or cyclophosphamide are recommended for severe forms of MPA with a life-threatening outcome [22]. Azathioprine and methotrexate have been validated as remission maintenance treatments [31]**.** By extrapolation of their efficacy in good pasture's syndrome, plasma exchange is indicated in fulminant forms of MPA with severe renal involvement and/or alveolar hemorrhage. Currently, rituximab is also recommended for remission induction in case of refractory disease [28]**.**


**5. Mainstreaming of traditional ecological customary law in the rule of biodiversity conservation law**

The role of traditional ecological customary law in the rule of law in biodiversity conservation, especially whether it is influential in protecting genetic resources and its associated traditional knowledge, depends to some extent on the degree of recognition of customary law in the formal legal system. Legal systems that recognize the legal status of customary law and develop specific implementing regulations are vital to protecting genetic resources and their associated traditional knowledge. As mentioned above, traditional ecological customary law is often regarded only as an informal custom because it has no record and no statute law. Even if it is regarded as a formal legal system source, it cannot change its weak status. Although, in practice, customary law is subordinate to statutory law, especially when there is a conflict between the two, customary law is often ignored.

Across the world, an increasing number of countries that are parties to the Convention on Biological Diversity have increasingly recognized the role of customary law in access to genetic resources and their associated traditional knowledge and benefit sharing and thus have recognized customary law. At present, relevant countries, including India, Brazil, South Africa, Malaysia, and the Andean Community, have formulated laws and systems for biological species resources and their related traditional knowledge, and have gradually begun to protect, manage, and control biological species resources and their related traditional knowledge. In addition, sustainable use and other aspects recognize and accept the traditional ecological customary laws and systems of traditional ethnic societies such as indigenous peoples, long-term inhabitants, indigenous peoples, and local communities and integrate them into the modern environmental legal system.

Based on the experience of the countries mentioned above, the international community and governments of various countries should explore the mainstreaming of traditional ecological customary law in the rule of law in biodiversity conservation and must carefully review the status of customary law in the construction of the rule of law in biodiversity conservation and discuss strengthening customary law, way, and method. To create traditional ecological customary law status, indigenous peoples and local communities must first establish their rights to genetic resources and associated traditional knowledge. Customary law can only be recognized if it respects the right of indigenous peoples and local communities to decide whether and how to use genetic resources and their associated traditional knowledge and under what conditions. Therefore, customary rights in traditional ecological law are at the core of protecting biodiversity genetic resources and their associated traditional knowledge. At the same time, recognizing the status of traditional ecological customary law requires understanding its basic principles and procedures. It needs to be recognized and strengthened in formal laws to ensure that customary laws and rights are recognized in practice by the formal legal system.

In conclusion, for the conservation and use of biodiversity, establishing a system of access and benefit sharing based on the recognition of customary law for genetic resources and their associated traditional knowledge is critical. It not only promotes biodiversity and ecosystem sustainability but also lays the groundwork for the conservation and use of biological diversity and its associated traditional knowledge. The endogeneity of conventional knowledge can shape the effective conservation and sustainable use of indigenous peoples and local communities' biodiversity in turn.


**2.8 Synthesis of 2-(4-fluorophenyl)-1,4,5-triphenyl-1***H***-imidazole (C27H19FN2): FPTPI**

Over an hour at a constant temperature of 333 K, 15 mmol of aniline, 15 mmol of ammonium acetate, and 15 mmol of p-fluorobenzaldehyde were added to 15 mmol of benzil in 10 ml of ethanol. The actions that follow are completed in the manner outlined in DMDPIMH. The yield was 3.51 g or 60% (**Figure 1**). The X-ray diffraction data were gathered using a suitable single crystal [17].


**1. Introduction**

Computational Intelligence in Electromyography Analysis – 36 A Perspective on Current Applications and Future Challenges

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Since its commercial advent in 1985, transcranial magnetic stimulation (TMS), a technique for stimulating neurons in the cerebral cortex through the scalp, safely and with minimal discomfort, has captured the imaginations of scientists, clinicians and lay observers [Wassermann et al, 2012]. Initially a laboratory tool for neurophysiologists studying the human motor system, TMS now has a growing list of applications in clinical and basic neuroscience. At cortical level, the abnormal amplitudes of the motor evoked potentials (MEP) may be due to the damage of the motoneurons themselves; as well as to their reduced capacity for repetitive excitation; deficit of the intracortical synaptic transmission (transfer); activation of motoneuron inhibitors, etc. At subcortical level the causes may be demyelinization, remyelinization, activation of the long-latent corticofugal fibres, axonal damage, etc. [Komori et al, 1993].

The human brain possesses a remarkable ability to adapt in response to changing anatomical (e.g., aging) or environmental modifications. This form of neuroplasticity is important at all stages of life but is critical in neurological disorders such as amblyopia and stroke [Sharma, 2012]. When MEP are obtained in the acute phase of stroke, the functional recovery of the motor deficit, as a rule, is to occur [Nowak et al, 2010; Dimyan, 2010]. The initially registered normal MEP amplitudes have a predictive value in the view of the longterm functional outcome [Stinear, 2010; Dimyan et al, 2010;].

The TMS approach was also used in the investigation of patients with lacunar strokes. The central motor conduction time (CMCT) and the threshold intensities for eliciting MEPs in the relaxed muscles were significantly increased on the affected side. MEP amplitude abnormalities were related to pyramidal signs (though they could be observed also in a

patient without any motor impairment) and occurred independently of a specific clinical picture or a radiologically confirmed lacunar lesion [Abbruzzese et al, 1991; Hufnagel et al, 1990]. Earlier studies have shown that during the acute phase of the minor ischaemic stroke (MIS), MEP amplitudes can be registered in all investigated patients [Hadjipetrova et al, 1993]. To note, the increases in the latency of the M-response and CMCT have prognostic significance for early assessment of the outcome of ischaemic stroke [Stulin et al, 2003]. Earlier studies by Ferbert and collaborators [1992] have indicated that the MEP amplitudes are a more sensitive marker for the sublclinical damage of the pyramidal tract than CMCT. A significant correlation has also been reported among the recovery of muscle strength and the amplitude of MEP [Palliyath, 2000].

Modelling of Transcranial Magnetic Stimulation in

One-Year Follow-Up Study of Patients with Minor Ischaemic Stroke 39

**Figure 1.** CONSORT flow-chart of study screening, enrolment and analysis.

the analysis.

disease, cardiac conditions, cigarette smoking, educational background, etc.

Data were collected by instructed physicians and clinical (physical and neurological) examinations were conducted by study neurologists [Atanassova, Chalakova & Dimitrov, 2008a]. The assessments covered: hypertension, diabetes, dyslipidaemia, peripheral vascular

Initial stroke severity was assessed using the modified Rankin Scale [Bamford et al, 1990]. MIS diagnostic evaluations included CT or MRI of the brain and ultrasound evaluation and/or trans-thoracic or trans-oesophageal echocardiogram, as appropriate. A panel of stroke neurologists assessed every CV events subtype using standard diagnostic criteria and all available information for each patient. For this study, *MIS* was defined as a minor stroke if the score on the modified Rankin Scale was 1 at the first evaluation, or if the score was 0 or 1 at one-month follow-up (i.e., no symptoms, or minor symptoms that did not interfere with normal lifestyle) [Atanassova, 1998; Atanasova & Vukov, 1998; Atanassova, Voukov & Tchalakova, 2002]. In particular, acute onset was observed in 11 patients (20.4%). Extracranial ultrasound findings were recorded in 11 patients (20.4%). The main characteristics of the initial study cohort were as follows: 37 men (68.5%) and 17 women (31.5%), with male predominance in CV events (n=8 men) but with similar ages of 61.1±12.6 years in patients with CVE versus 62.2±9.2 years in patients without CVE (p>0.05). The mean follow-up time was 11.1±2.4 months with mean time to CV events of 5.8±2.7 months. For the purpose of this study, all MIS patients with subsequent stroke (n=8) as defined above, were excluded from

The aim of this study was to perform a *post-hoc* analysis of one-year follow-up data from 40 patients with MIS and to: (i) investigate the central motor conduction time (CMCT) and the amplitude of the motor evoked potential (MEP) during the acute phase of MIS; (ii) provide evidence for a subclinical damage of the pyramidal tract; and (iii) model and predict the outcome measures at month 12 after MIS as based on earlier changes in the acute phase.


*Article* **Effect of Wettability and Adhesion Property of Solid Margins on Water Drainage**

**Can Gao 1,2, Lei Jiang 1,2 and Zhichao Dong 1,2,\***

**\*** Correspondence<EMAIL_ADDRESS>
**Abstract:** Liquid flows at the solid surface and drains at the margin under gravity are ubiquitous in our daily lives. Previous research mainly focuses on the effect of substantial margin's wettability on liquid pinning and has proved that hydrophobicity inhibits liquids from overflowing margins while hydrophilicity plays the opposite role. However, the effect of solid margins' adhesion properties and their synergy with wettability on the overflowing behavior of water and resultant drainage behaviors are rarely studied, especially for large-volume water accumulation on the solid surface. Here, we report the solid surfaces with high-adhesion hydrophilic margin and hydrophobic margin stably pin the air-water-solid triple contact lines at the solid bottom and solid margin, respectively, and then drain water faster through stable water channels termed water channel-based drainage over a wide range of water flow rates. The hydrophilic margin promotes the overflowing of water from top to bottom. It constructs a stable "top + margin + bottom" water channel, and a high-adhesion hydrophobic margin inhibits the overflowing from margin to bottom and constructs a stable "top + margin" water channel. The constructed water channels essentially decrease marginal capillary resistances, guide top water onto the bottom or margin, and assist in draining water faster, under which gravity readily overcomes the surface tension resistance. Consequently, the water channelbased drainage mode achieves 5–8 times faster drainage behavior than the no-water channel drainage mode. The theoretical force analysis also predicts the experimental drainage volumes for different drainage modes. Overall, this article reveals marginal adhesion and wettability-dependent drainage modes and provides motivations for drainage plane design and relevant dynamic liquid-solid interaction for various applications.

**Keywords:** solid margin; high adhesion; water channel; fast water drainage

### **1. Introduction**

Fast water drainage, ranging from tiny droplets [1–4] to large-volume liquid [5–8], from solid surfaces is ubiquitous and critical to self-cleaning [9], water harvesting [1–4,10], and creature survival [11–13]. Natural surfaces, such as mosquito compound eyes [14], water strider legs [15], and drain fly tentacles [16], utilize complicated microstructures to quickly drain tiny water droplets based on surface energy or Laplace pressure gradient. Artificial surfaces can achieve preferable spontaneous and rapid water droplet removal under asymmetrical surface tension force [17–20] or external forces [21–28]. Plants' leaves have evolved special structures, such as the drip tip apex structure [12], to rapidly remove large-volume rainwater under the gravity effect. In practice, large-volume water drainage behavior based on the overflowing of water around the solid margin can also be manipulated depending on the water flow rate and solid margin wettability [5–8,29] in a controllable manner. However, previous research mainly focuses on tiny droplet drainage at sharp spine-shaped margins or liquid columns/sheets at circle-shaped margins. Studies on the effect of the wettability and adhesion property of the macroscopic square-shaped

**Citation:** Gao, C.; Jiang, L.; Dong, Z. Effect of Wettability and Adhesion Property of Solid Margins on Water Drainage. *Biomimetics* **2023**, *8*, 60. https://doi.org/10.3390/ biomimetics8010060

Academic Editors: Stanislav N. Gorb, Giuseppe Carbone, Thomas Speck and Andreas Taubert

Received: 11 January 2023 Revised: 28 January 2023 Accepted: 30 January 2023 Published: 1 February 2023

**Copyright:** © 2023 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

margins on water drainage are rare, mainly when large-volume water accumulates at margins with a low slope.

Here, we establish a water channel-based faster drainage mode based on the highadhesion hydrophilic and hydrophobic solid margins over a wide range of water flow rates. We demonstrate that the low-adhesion margins, the superhydrophobic one, the original one, and the hydrophobic one result in more significant marginal resistances and subsequent higher drainage time and drainage volumes. In contrast, the high-adhesion margins, the hydrophilic and the hydrophobic ones, construct stable water channels, quickly transport top water onto the bottom or margin, and drain water faster with less drainage time and drainage volumes. In this condition, water droplet gravity readily overcomes surface tension resistance based on the as-formed water channels. Notably, the high-adhesion hydrophobic margin sample with the highest contact angle hysteresis exhibits the fastest drainage behavior. We emphasize that stable water channels always exist for the high-adhesion margins regardless of different water flow rates, initial incline angles, and sample thicknesses. We also show the determination of the critical water flow rates versus sample thicknesses for water channel constructions associated with the original margin sample. That is, only more considerable inertia can sustain stable water channels. Further, this investigation will offer us an innovative insight into how to design structured margin planes with high-efficiency drainage behavior, especially in large-volume water accumulation situations.

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


**2. Materials and Methods**

### *2.1. Particle Generation and Thermal Treatment*

Graphite was selected to produce aBC generated from a spark discharge soot generator (DNP Digital 3000, Palas GmbH, Karlsruhe, Germany). It operates on the principle of spark discharge to produce nanoscale particles of consistent concentration in high yields and negligible volatile content. The generator maintains a jump spark between two graphite electrodes at a high voltage of 2500 V. Graphite is vaporized by this spark, and then condenses to form particles with a size distribution and structure similar to those of diesel soot. The generator was operated under a constant flow of carrier inert Ar gas and purified dilution air at flow rates of 5 and 10 LPM, respectively (gas streams were controlled with a series of mass flow controllers).

The generated particles were produced in a tubular furnace at different ranges of temperatures. The first experiment was performed with the furnace temperature increasing continuously from room temperature (RT) to 800 ◦C to investigate particle properties as a function of the treatment temperature. Five treatment temperatures (RT, 200 ◦C, 400 ◦C, 600 ◦C and 800 ◦C) were applied separately in the second experiment to evaluate the effects of temperature on the physicochemical properties of aBC. A schematic of the experimental setup, including the sampling and measuring devices, is presented in Figure 1.

**Figure 1.** Schematic of the experimental setup.


*Article* **3D Photoacoustic Tomography System Based on Full-View Illumination and Ultrasound Detection**

#### **Mingjian Sun 1,2,\*, Depeng Hu 1, Wenxue Zhou 1, Yang Liu 2, Yawei Qu 2 and Liyong Ma 1**

Received: 25 March 2019; Accepted: 6 May 2019; Published: 9 May 2019

**Abstract:** A 3D photoacoustic computed tomography (3D-PACT) system based on full-view illumination and ultrasound detection was developed and applied to 3D photoacoustic imaging of several phantoms. The system utilized an optics cage design to achieve full-view uniform laser illumination and completed 3D scanning with the rotation of a dual-element transducer (5 MHz) and the vertical motion of imaging target, which obtains the best solution in the mutual restriction relation between cost and performance. The 3D-PACT system exhibits a spatial resolution on the order of 300 μm, and the imaging area can be up to 52 mm in diameter. The transducers used in the system provides tomography imaging with large fields of view. In addition, the coplanar uniform illumination and acoustic detection configuration based on a quartz bowl greatly enhances the e fficiency of laser illumination and signal detection, making it available for use on samples with irregular surfaces. Performance testing and 3D photoacoustic experiments on various phantoms verify that the system can perform 3D photoacoustic imaging on targets with complex surfaces or large sizes. In future, e fforts will be made to achieve full-body 3D tomography of small animals and a multimodal 3D imaging system.

**Keywords:** 3D photoacoustic tomography; full-view illumination and ultrasound detection; photoacoustic coplanar; quartz bowl


2. Specimen size and geometry influence on fracture toughness parameters

The effect of the specimen size and the geometry is variable with the material fracture behavior. Most of the technical materials exhibit transition behavior, and thus three basic regions can be distinguished: the lower shelf, transition and upper shelf.

All values of KJ could be obtained by conversion from J-values using Eq. (1):

but prior to attaining the maximum load (the onset of the transition region).

scatter of material properties, tB could be within the (tDBL-tDBU) region. tC—the lower shelf fracture toughness regime is below this temperature.

2.1. Brittle region (lower shelf region)

tDBL—ductile-brittle lower; the end of the region with the above fracture mode.

The following transition temperatures are denoted in the diagrams:

Figure 1. Schematic representation of fracture toughness-temperature dependence.

KJ ¼

ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi J:E 1 � ν2 ð Þ s

Fracture Toughness Determination with the Use of Miniaturized Specimens

http://dx.doi.org/10.5772/intechopen.73093

tDBU—ductile-brittle upper; the cleavage fracture occurs after certain amount of ductile tearing

tB—brittle-fracture transition temperature; the onset of the region, where cleavage fracture is initiated ahead of the blunted crack tip but without prior ductile tearing. Due to inherent

When a material behaves in a linear elastic manner prior to failure, such that the plastic zone is small compared to the specimen dimensions, a critical value of the Mode I stress intensity factor KIc may be an appropriate fracture parameter. In the ASTM E 399 [3] and similar test methods, KIc is referred to as "plane strain fracture toughness." Four specimen configurations are permitted for the fracture toughness determination by the current version of E 399: the compact tension (CT), single edge-notched bend bar (SE(B)), arc-shaped and disc-shaped specimens. However,

(1)

145

Holzmann and Vlach [1, 2] suggested schematic diagram of fracture toughness behavior with temperature (see Figure 1), where following fracture toughness parameters are used for an analysis of the fracture behavior:

KJ0.2—fracture toughness after 0.2 mm of blunting and crack extension.

KJm—value of KJ at the maximum load Fmax for stable fracture behavior and nonlinear test record.

KJu—post-ductile tearing cleavage fracture toughness; only Jc-tests terminated by cleavage prior to attaining the maximum load Fmax were taken into account.

KJC—fracture toughness for the onset of cleavage fracture after elastic-plastic deformation, but with no prior ductile tearing.

KC—the fracture toughness at the onset of brittle fracture; test record linear or with no significant deviation from linearity, but size validity requirements of ASTM E399 are not met.

KIC—plane strain fracture toughness.

Fracture Toughness Determination with the Use of Miniaturized Specimens http://dx.doi.org/10.5772/intechopen.73093 145

Figure 1. Schematic representation of fracture toughness-temperature dependence.

All values of KJ could be obtained by conversion from J-values using Eq. (1):

$$K\_{\rm J} = \sqrt{\frac{\rm J.E.}{(1 - \nu^2)}}\tag{1}$$

The following transition temperatures are denoted in the diagrams:

tDBU—ductile-brittle upper; the cleavage fracture occurs after certain amount of ductile tearing but prior to attaining the maximum load (the onset of the transition region).

tDBL—ductile-brittle lower; the end of the region with the above fracture mode.

tB—brittle-fracture transition temperature; the onset of the region, where cleavage fracture is initiated ahead of the blunted crack tip but without prior ductile tearing. Due to inherent scatter of material properties, tB could be within the (tDBL-tDBU) region.

tC—the lower shelf fracture toughness regime is below this temperature.

#### 2.1. Brittle region (lower shelf region)

experimental material is only available can be residual service life assessment of in-service components, when the experimental material only by semi-destructive approach can be obtained. Cases during development of new materials, generally preparation of the materials with limited volume such as severe plastic deformation processes for bulk nanomaterials preparation. Recently, also for the assessment of the parts produced by additive manufacturing

This chapter is going to provide overview of reporting values of the results obtained with the use of miniaturized specimens with hints how can be small-size-based results related to the standard-sized specimen results. These techniques enable assessment of the fracture behavior from small material volumes allowing, for example, also local anisotropy assessment. In the first part of the chapter, some theoretical background for small-size specimen testing is provided for different fracture regime behaviors ranging from brittle up to full ductile behavior. Several mini specimens' geometries are demonstrated here that are subsequently applied on the experimental materials. Three materials are presented here, ferritic steel used for Master Curve-based assessment and then stainless steel and Ti-alloy produced by additive manufacturing technology. The results are summarized in order to provide inside into the facture behavior assessment with the use of miniaturized specimens providing background for practical application of these

2. Specimen size and geometry influence on fracture toughness

be distinguished: the lower shelf, transition and upper shelf.

KJ0.2—fracture toughness after 0.2 mm of blunting and crack extension.

prior to attaining the maximum load Fmax were taken into account.

The effect of the specimen size and the geometry is variable with the material fracture behavior. Most of the technical materials exhibit transition behavior, and thus three basic regions can

Holzmann and Vlach [1, 2] suggested schematic diagram of fracture toughness behavior with temperature (see Figure 1), where following fracture toughness parameters are used for an

KJm—value of KJ at the maximum load Fmax for stable fracture behavior and nonlinear test

KJu—post-ductile tearing cleavage fracture toughness; only Jc-tests terminated by cleavage

KJC—fracture toughness for the onset of cleavage fracture after elastic-plastic deformation, but

KC—the fracture toughness at the onset of brittle fracture; test record linear or with no significant deviation from linearity, but size validity requirements of ASTM E399 are not met.

techniques are application for small-size specimen testing.

approaches.

144 Contact and Fracture Mechanics

parameters

record.

analysis of the fracture behavior:

with no prior ductile tearing.

KIC—plane strain fracture toughness.

When a material behaves in a linear elastic manner prior to failure, such that the plastic zone is small compared to the specimen dimensions, a critical value of the Mode I stress intensity factor KIc may be an appropriate fracture parameter. In the ASTM E 399 [3] and similar test methods, KIc is referred to as "plane strain fracture toughness." Four specimen configurations are permitted for the fracture toughness determination by the current version of E 399: the compact tension (CT), single edge-notched bend bar (SE(B)), arc-shaped and disc-shaped specimens. However,

strain condition for thickness 1.6 mm. Considering investigated material in this chapter, Table 2 shows hypothetic KIc value under plain strain condition for different specimen geometries and sizes. Note that the toughness level calculated here corresponds to the lower shelf for these materials. Thus valid KIc tests on these materials would be possible only at low

Fracture Toughness Determination with the Use of Miniaturized Specimens

http://dx.doi.org/10.5772/intechopen.73093

147

In ASTM E 399 it is listed that "Variation in the value of KIc can be expected within the allowable range of specimen proportions, a/W and W/B. KIc may also be expected to rise with increasing ligament size. Notwithstanding these variations, however, KIc is believed to represent a lower limiting value of fracture toughness (for 2 % apparent crack extension) in the

Therefore, valid KIc is generally accepted as size-independent value though some minor deviation could not be avoided. As it can be seen from Tables 1 and 2, it is very difficult to obtain valid fracture toughness values with the use of subsized specimens in this region, except for very brittle materials. Therefore, subsided specimens will most yield size-dependent values of

In this region, micro-mechanisms of cleavage fracture cause that the cleavage toughness data tend to be highly scattered when compared to the lower shelf region, and thus a statistical analysis must be performed as shown in Table 3. Rather than single value of toughness at a particular temperature, the material has a toughness distribution. Research over the past three decades on the fracture of ferritic steels in the ductile-brittle transition region has led to two

Material Specimen geometry and size σYS B, a Requested KIc

M-CT 4.0 20.1 CVN 10 10 55 10.0 31.7 KLST 4 2 27 2.0 14.2

M-CT 4.0 26.3 CVN 10 10 55 10.0 41.6 KLST 4 2 27 2.0 18.6

M-CT 4.0 37.1 CVN 10 10 55 10.0 58.6 KLST 4 2 27 2.0 26.2

15CH2NMFA 1 T-CT 502 25.0 50.2

AISI 304 1 T-CT 657 25.0 65.7

AM Ti6Al4V 1 T-CT 927 25.0 92.7

Table 2. Calculated requested parameter KIc for valid plain strain condition considering investigated material in this chapter.

MPa mm MPa.m0.5

temperatures, where the materials are too brittle for most structural applications.

environment and at the speed and temperature of the test."

the fracture toughness.

important conclusions:

2.2. Ductile-brittle transition region

Figure 2. Comparison of the profiles of CT and SE(B) specimens with the same in-plane characteristic dimensions (B, W, a).

the vast majority of fracture toughness tests are performed on either CT or SE(B) specimens. Figure 2 shows basic dimensions of both types of specimens of these two specimen types, assuming the same characteristic dimensions (B, W, a). It can be seen that the specimen design is such that all of the key dimensions (i.e., a, B and W � a) are approximately equal and, thus, geometry selection is only question of less material consumption from semi-product.

In order to fulfill the size requirements for size-independent fracture toughness value determination according to the ASTM E399, the minimal specimen thickness is 1.6 mm, while the specimen ligament size (W-a) must be not less than 2.5(KIc/σYS) 2 , where σYS is the 0.2% offset yield strength. Considering recommended proportion of the thickness B which is nominally one-half the specimen width W and crack length, a, is nominally between 0.45 and 0.55 times the width W, the thickness must be also not less than 2.5(KIc/σYS) 2 . These limits could be expressed using Eq. (2), which is not literally listed in the standard ASTM E399 but is noted in Anderson [4]:

$$B, a, (\mathcal{W} - a) \ge 2, \dots \ge \left(\frac{\mathcal{K}\_{\text{IC}}}{\sigma\_{\text{YS}}}\right)^2\\0.45 \le a/\mathcal{W} \le 0.55\tag{2}$$

Because the size requirements of ASTM E 399 are very stringent, it is very difficult and sometimes impossible to measure a valid KIc for most of the structural materials. As an example, we can consider structural steel with σYS = 330 MPa and typical KIc values of 210 MPa.m0.5. According to Eq. (2), the required thickness must be higher than 1 m, and the width (since a/W = 0.5) must be more than 2 m (see Table 1). Materials are seldom available in such dimensions, and if yes, machining and testing would have to be done using special machine, and all investigation would be extremely expensive. On the other hand, material such as tool steels exhibits high yield strength and low fracture toughness, and Table 1 shows combination of these two values for obtaining valid fracture toughness value under plain

Table 1. Examples of the calculated thickness B for given σYS and KIc values.

strain condition for thickness 1.6 mm. Considering investigated material in this chapter, Table 2 shows hypothetic KIc value under plain strain condition for different specimen geometries and sizes. Note that the toughness level calculated here corresponds to the lower shelf for these materials. Thus valid KIc tests on these materials would be possible only at low temperatures, where the materials are too brittle for most structural applications.

In ASTM E 399 it is listed that "Variation in the value of KIc can be expected within the allowable range of specimen proportions, a/W and W/B. KIc may also be expected to rise with increasing ligament size. Notwithstanding these variations, however, KIc is believed to represent a lower limiting value of fracture toughness (for 2 % apparent crack extension) in the environment and at the speed and temperature of the test."

Therefore, valid KIc is generally accepted as size-independent value though some minor deviation could not be avoided. As it can be seen from Tables 1 and 2, it is very difficult to obtain valid fracture toughness values with the use of subsized specimens in this region, except for very brittle materials. Therefore, subsided specimens will most yield size-dependent values of the fracture toughness.


*3.1.2 Fractured teeth and forced eruption*

Trauma to the upper anterior is the most common occurrence in children and adolescents. This trauma can be (a) fracture of the crown or (b) fracture of crown and root. If the fracture is restricted to the crown, then endodontics and restorative procedures will be sufficient to manage. If the fracture extends into the biological width, then any restoration will cause irritation and inflammation to the marginal gingiva. Alternatively, extrusion of the tooth followed by restoration may be possible depending on the amount of tooth structure [34]. If the fracture extends to the root, then, depending on the level of involvement the tooth may have to be extracted. There are six criterias used to determine the direction of treatment to choose:

If all the above criteria are favorable, forced eruption of teeth can be considered. It can be carried out with orthodontic brackets or with composite extension with elastics. If the tooth movement is faster, the bone will not follow the root, hence circumferential fibrotomy would be necessary. If the tooth movement is slow, the bone follows the root and crown lengthening procedure may be required for the restorative phase.

After the forced extrusion, teeth must be stabilized to prevent re-intrusion, which may occur due to the orientation of the oblique fibers, which will allow intrusion with any compressive force, until 6 months post treatment [33].

Usually during forced eruption, the clinical crown length may be shortened. This is because the gingiva follows the direction of eruption of the teeth. If there is a mismatch in the bone levels with the adjacent teeth, flap elevation and bone recontouring followed by gingivectomy can be considered. If the mismatch is limited only to the gingival heights then gingivectomy is sufficient [32, 34].

Post gingival surgery, embrasures due to the difference in the widths of root and crown may be seen. These can be corrected either by re- contouring the teeth or by reshaping the crowns during space closure. The latter is preferred because it improves the overall shape of the final crown [35].

#### *<IP_ADDRESS> Hopeless teeth maintained for orthodontic anchorage*

In certain cases, moderate to severe periodontally compromised teeth may be used for anchorage. Even though the tooth is compromised, with sufficient bone it may be used for anchorage. Flap surgery and root debridement can improve the quality of this anchorage unit and post orthodontics, these can be maintained as are or extracted and replaced [36].

#### *3.1.3 Orthodontic treatment of gingival discrepancies*

#### *<IP_ADDRESS> Uneven gingival margins*

The gingival margins of the anterior teeth play an important role in esthetics. The four factors that need to be considered for good esthetics are: (a) The height of the gingival margins of upper central incisors should be equal, (b) Gingival margin of lateral incisor should be coronal to the central incisor, (c) The gingival contour should follow the shape of CEJs in the anterior region, (d) Gingival papilla should occupy half the distance from the highest point of gingival contour to the incisal edge; the remaining half should be tooth contact [37].

The cause of the marginal discrepancies should be appropriately diagnosed and treated by either orthodontics or gingival surgery.

Four steps that can be considered for planning the treatment are: [36, 37]

Lip line: When the patient smiles, if the gingival discrepancy is not visible, it can be left untreated. If it is visible, then step two should be evaluated.

Labial sulcular depth: in the presence of an uneven gingival margin, if the labial sulcular depth is greater than 1 mm, then gingivectomy is possible. If the labial sulcular depth is less than 1 mm, then step three should be evaluated.

*Orthodontic-Periodontics: An Interdisciplinary Approach DOI: http://dx.doi.org/10.5772/intechopen.98627*

Relationship to the adjacent incisors: If the Central incisor is longer than the adjacent lateral incisor, orthodontic extrusion of this incisor will allow the gingival margins to move apically. The extruded tooth will have to be leveled with the adjacent teeth. If the Central incisor is shorter than the adjacent lateral incisor, then step four should be evaluated.

Abrasion: The incisal edges should be checked in the occlusal view. If this is thicker than the adjacent central incisor, then extrusion has taken place. Then the treatment of choice would be intrusion of the affected central incisors which will move the gingival margin apically. Followed by restoration of incisal edges. This step should be completed 6 months prior to the appliance removal as the periodontal fibers need time for re-orientation.

#### *<IP_ADDRESS> Significant abrasion and over eruption*

When the patient reports with an abraded anterior, it can be managed either by orthodontic extrusion and restoration of the anterior tooth or by orthodontic intrusion of the adjacent anterior teeth followed by restoration of incisal edges. The extrusion option is not preferred as it may alter the crown: root ratio (1:1). It is advisable to intrude the anteriors. Extrusion of posterior teeth is not possible due to the occlusal forces. Once the intrusion has been achieved it is followed by a retention phase for 6 months after which restorations on the incisal edges can reestablish the ideal crown height [38].

#### *<IP_ADDRESS> Open gingival embrassures*

The gingival embrasures can be deficit or open due to several reasons such as: (1) root position, (2) underlying bone loss, and (3) shape of the crown. If the problem is due to divergent roots, then orthodontic correction with modification of bracket position is an option. Once the root position is corrected, changes in the incisal contact can be modified. If the open gingival embrasure is due to other reasons, intrusion of the teeth would be ideal. Orthodontic intrusion will lead to compression of spaces which will in turn lead to an occlusal push of interdental gingiva, thus achieving the ideal ratio of 1:1, embrasure to tooth contact [34].

#### **4. Conclusion**

Adjunctive orthodontic treatment for patients with periodontal disease has some unique effects. Orthodontic treatment should only be done on a clinically sound periodontium. It is essential for dentists to have adequate knowledge on perio-ortho interrelationship. Maintaining a good oral hygiene and receiving regular basic periodontal care is of outmost importance to achieve a more effective orthodontic treatment. A better outcome can be achieved along with good maintenance, through a close collaboration between the orthodontist and the periodontist.

#### **Acknowledgements**

We would like to acknowledge the contribution of Dr. Kavarathapu Avinash, Periodontist and Implantologist, and Dr. Joseph Abraham, Orthodontist for generously sharing their clinical case photographs for our chapter.

Last but not the least, we would like to thank our parents and families, our teachers and mentors for their never-ending support and guidance.


**Abstract**

The introduction of industry 4.0 technologies, including artificial intelligence (AI), the Internet of Things (IoT), and other cutting-edge technological developments, has completely transformed traditional library practises in higher education. Despite the topic's unquestionable importance, the main objective of this chapter is to address the effects of IoT technology and it is inconsistent and dispersed. However, there are various challenges, such as accurate reservation methods, real-time seat occupancy tracking, and reservation time estimation. To discover, compare, and characterize current investigations in the Smart Library Seat Occupancy and Reservation system (SLSORS), this proposed book chapter examined articles published between 2016 and 2022. In the SLSORS, we will also give a thorough taxonomy and perform a technical analysis of the articles. This provides the much-needed clarity regarding the problems associated with SLSORS and their available literature-based solutions. The fundamental taxonomy is framed by the reservation security, seat reservation, seat selection, and seat availability criteria. Thus, the benefits and drawbacks of the selected approaches are also offered, along with a full comparison of evaluation methodology, evaluation tools, and evaluation metrics. Furthermore, this chapter incorporates all processes and method for SLSORS and drew attention to the ongoing challenges that this chapter is seeking to address.

**Keywords:** Internet of Things (IoT), radio frequency identification (RFID), force sensitive resistor (FSR), smart library, seat occupancy and reservation, wireless sensor network (WSN)


**3.1 Band structure – variation with k-grid**

We have been intrigued by the potential to directly determine the superconducting gap energy for a BCS SC using an appropriate resolution EBS. In this regard, MgB2 offers good opportunity to evaluate this potential due to well defined

### *Real Perspective of Fourier Transforms and Current Developments in Superconductivity*

crystallography and the key role ascribed to σ bands and superconductivity [12, 34]. DFT calculations for a compositional suite, or structure type, produce EBSs that show, in general, similar formats even when two different functional approximations are used [26]. A typical outcome for MgB2 using the LDA approximation in the CASTEP module of Materials Studio using a k-grid value of 0.008 Å−1 is shown in **Figure 1**. These band structures convey useful information for elucidation of potential for superconductivity. For example, the σ bands appear as approximate inverted parabolas (in red and blue lines; green dotted box) near the Γ center point and cross the Fermi level on either side of Γ (**Figure 1**). These bands display a strong electron–phonon coupling to the E2g phonon modes and are implicated in superconductivity for MgB2 *via* both theoretical and experimental analyses [35–38].

**Figure 1.**

*Electronic band structure for MgB2 calculated with the LDA approximation for k = 0.008 Å−1 using the CASTEP module of materials studio [9]. The green boxes enclose sections of* σ *bands.*

### **Figure 2.**

*Schematic showing the direct relationship between* σ *bands crossing the Fermi level around* Γ *and the topology of the FS.*

**117**

for MgB2.

**Figure 3.**

*Insights from Systematic DFT Calculations on Superconductors*

For MgB2, the relationship of these σ bands near the Fermi level on either side of Γ is shown in the schematic in **Figure 2**. The reciprocal space projection of degenerate σ bands at the Fermi level correspond to the three-dimensional reciprocal space representations of two FSs at Γ parallel with the *k*z direction. That is, except for the direction along *k*z, the band is a 2D projection at *k*z = 0 of the 3D Fermi surface representation. The region between these two FSs is sensitive to the reciprocal space projection(s) at the Fermi level and, as noted in previous work, is key to the super-

*Electronic band structure for MgB2 calculated with the LDA approximation for k-grid values 0.02 Å−1 (red), 0.04 Å−1 (blue) and 0.06 Å−1 (black) using the CASTEP module of materials studio. Notice the substantial*

*differences in band energies, particularly in regions associated with the* σ *bands.*

Variations in the calculated energies of specific bands, for example in MgB2 where electron–phonon coupling is predominantly linked to the σ bands [17, 39, 40], are strongly influenced by the k-grid value used in DFT computations. **Figure 3** demonstrates the effect of k-grid value, or the sensitivity of DFT calculations, on the EBS for MgB2 using the LDA functional for a series of Δk values 0.02 Å−1, 0.04 Å−1 and 0.06 Å−1. The k-grid value affects calculated energies for bands near the Fermi level particularly those σ bands associated with superconductivity highlighted in **Figure 1** for MgB2. The differences in energy at Γ or A between calculations range from tens of meV to hundreds of meV for three different k-grid values as shown in **Figure 3**. In **Table 1**, we show substantial meV shifts in enthalpy and EF for MgB2 calculated at different k-grid values using the same functional and the same ultra-fine tolerance for geometry optimization convergence. For MgB2, **Table 1** shows the difference in energy, ΔEv (in eV), between the Fermi level and the vertex of the parabola at Γ for different values of Δk. Differences in lattice parameters (*i.e.* ~0.01 Å), enthalpy values (*i.e.* ~10–20 meV) and EF values (*i.e.* ~200 meV) are evident for geometry optimized calculations with different k-grids. **Table 1** also shows that as the Δk value is reduced, values for enthalpy achieve a consistent value

We also show calculated values for B-doped diamond using different k-grid values in **Table 1**. In this case, k-grid intervals are smaller (0.005 Å−1 < Δk < 0.020 Å−1) than those used for MgB2 with corresponding smaller shifts in enthalpy and EF. This lower magnitude impact of the k-grid is in part due to fewer degrees of freedom (*e.g.* cubic symmetry compared to hexagonal) and a significantly lower value for Tc [32, 33], with corresponding FSs in closer reciprocal space proximity. Nevertheless, the EF value

*DOI: http://dx.doi.org/10.5772/intechopen.96960*

conducting mechanism in MgB2 [27, 28].

*Insights from Systematic DFT Calculations on Superconductors DOI: http://dx.doi.org/10.5772/intechopen.96960*

### **Figure 3.**

*Real Perspective of Fourier Transforms and Current Developments in Superconductivity*

ductivity for MgB2 *via* both theoretical and experimental analyses [35–38].

*Electronic band structure for MgB2 calculated with the LDA approximation for k = 0.008 Å−1 using the*

*Schematic showing the direct relationship between* σ *bands crossing the Fermi level around* Γ *and the topology*

*CASTEP module of materials studio [9]. The green boxes enclose sections of* σ *bands.*

crystallography and the key role ascribed to σ bands and superconductivity [12, 34]. DFT calculations for a compositional suite, or structure type, produce EBSs that show, in general, similar formats even when two different functional approximations are used [26]. A typical outcome for MgB2 using the LDA approximation in the CASTEP module of Materials Studio using a k-grid value of 0.008 Å−1 is shown in **Figure 1**. These band structures convey useful information for elucidation of potential for superconductivity. For example, the σ bands appear as approximate inverted parabolas (in red and blue lines; green dotted box) near the Γ center point and cross the Fermi level on either side of Γ (**Figure 1**). These bands display a strong electron–phonon coupling to the E2g phonon modes and are implicated in supercon-

**116**

**Figure 2.**

*of the FS.*

**Figure 1.**

*Electronic band structure for MgB2 calculated with the LDA approximation for k-grid values 0.02 Å−1 (red), 0.04 Å−1 (blue) and 0.06 Å−1 (black) using the CASTEP module of materials studio. Notice the substantial differences in band energies, particularly in regions associated with the* σ *bands.*

For MgB2, the relationship of these σ bands near the Fermi level on either side of Γ is shown in the schematic in **Figure 2**. The reciprocal space projection of degenerate σ bands at the Fermi level correspond to the three-dimensional reciprocal space representations of two FSs at Γ parallel with the *k*z direction. That is, except for the direction along *k*z, the band is a 2D projection at *k*z = 0 of the 3D Fermi surface representation. The region between these two FSs is sensitive to the reciprocal space projection(s) at the Fermi level and, as noted in previous work, is key to the superconducting mechanism in MgB2 [27, 28].

Variations in the calculated energies of specific bands, for example in MgB2 where electron–phonon coupling is predominantly linked to the σ bands [17, 39, 40], are strongly influenced by the k-grid value used in DFT computations. **Figure 3** demonstrates the effect of k-grid value, or the sensitivity of DFT calculations, on the EBS for MgB2 using the LDA functional for a series of Δk values 0.02 Å−1, 0.04 Å−1 and 0.06 Å−1. The k-grid value affects calculated energies for bands near the Fermi level particularly those σ bands associated with superconductivity highlighted in **Figure 1** for MgB2. The differences in energy at Γ or A between calculations range from tens of meV to hundreds of meV for three different k-grid values as shown in **Figure 3**.

In **Table 1**, we show substantial meV shifts in enthalpy and EF for MgB2 calculated at different k-grid values using the same functional and the same ultra-fine tolerance for geometry optimization convergence. For MgB2, **Table 1** shows the difference in energy, ΔEv (in eV), between the Fermi level and the vertex of the parabola at Γ for different values of Δk. Differences in lattice parameters (*i.e.* ~0.01 Å), enthalpy values (*i.e.* ~10–20 meV) and EF values (*i.e.* ~200 meV) are evident for geometry optimized calculations with different k-grids. **Table 1** also shows that as the Δk value is reduced, values for enthalpy achieve a consistent value for MgB2.

We also show calculated values for B-doped diamond using different k-grid values in **Table 1**. In this case, k-grid intervals are smaller (0.005 Å−1 < Δk < 0.020 Å−1) than those used for MgB2 with corresponding smaller shifts in enthalpy and EF. This lower magnitude impact of the k-grid is in part due to fewer degrees of freedom (*e.g.* cubic symmetry compared to hexagonal) and a significantly lower value for Tc [32, 33], with corresponding FSs in closer reciprocal space proximity. Nevertheless, the EF value

**Table 1.**

*Parameters calculated for MgB2 and for B-doped diamond.*

differs by ~35 meV and the difference in energy to the vertex of the band at Γ (*i.e.* ΔEv) differs by up to ~35 meV depending on the Δk value.

We show a more detailed systematic comparison of calculated enthalpies as a function of the k-grid value for MgB2 in **Figure 4**. As noted above, all calculations are converged to the same ultra-fine criteria, or tolerance, where self-consistency is achieved. The variability of results shown in **Figure 4** is due to the discreteness of functions and values used to derive the full solution of the Schroedinger equation. The variability is not due to lack of convergence which in all cases is defined in Section 2 above.

**Figure 4a** shows that the value of enthalpy for MgB2 oscillates around a consistent minimal value of −1,748.502 eV as the k-grid value is decreased to <0.015 Å−1. The context for this variation in enthalpy is shown in **Figure 4b** where the k-grid value is extended to 0.2 Å−1– a value that has been used in some DFT calculations as criterion for machine learning algorithms [41]. At these higher values for Δk, enthalpy calculations do not provide useful information on subtle structural

### **Figure 4.**

*Systematic comparison of calculated enthalpies for MgB2 (a) for fine values of k-grid (i.e. < 0.03 Å−1) and (b) for coarser grid values including those utilized for machine learning searches (arrowed) of materials databases [41]. Enthalpies shown in Figure 4(a) are reproduced in (b) for reference. The lightly shaded region in Figure 2(b) delineates the k-grid values used for EBS calculation in Figure 3.*

**119**

**Figure 5.**

*superconductivity [26].*

*Insights from Systematic DFT Calculations on Superconductors*

variations due to superlattices or of order/disorder. For example, we have shown using DFT calculations with appropriate k-grid values for (Mg1-xAlx)B2 that ordered motifs with adjacent Al-layers are thermodynamically favored by ~0.15 eV over more complex, disordered configuration(s) [42]. A discrepancy of ~0.2 eV due to incorrect choice of k-grid value (**Figure 4**) does not enable such distinction to be

In a dynamic system, other factors may also influence the position of key electronic bands with respect to the Fermi level. For example, atoms in all solids at temperatures above absolute zero vibrate [43] and in some cases, the resulting phonons may align with specific crystallographic real space features such as inter-atom bonds. This circumstance occurs for MgB2 in which one of the dominant E2g phonon modes – shown to be intimately involved in electron–phonon coupling at the onset of superconductivity [17, 34] – aligns with B–B bonds in the *ab* plane [36]. Using DFT, we can model the effect of bond deformation along specific planar orientations by displacing atoms from their structural equilibrium positions consistent with the direction of the E2g phonons [26, 28]. Under different extents of displacement, electron density distributions along the B–B bond and the corresponding

**Figure 5** shows the effect on the EBS for MgB2 of atom displacement along the

B–B bond by ~0.6% (*i.e.* a shift of ~0.063 Å) from equilibrium [28]. **Figure 5** shows that the E2g phonon, which is degenerate at Γ with a peak parabola at 398 meV, splits into two separate non-degenerate bands above and below the equilibrium condition. The upper σ band - which we attribute to the heavy effective mass - has a calculated energy 813 meV above the Fermi level. Thus, parallel or nearly parallel FSs attributable to the superconducting condition [44], no longer exist with a 0.6% shift in atom position(s) [28]. A shift of atom position(s) is also reflected in the form and energy of key phonon modes in the corresponding PD for MgB2 [26]. An atom displacement of 0.6% along B–B for MgB2 is not unrea-

*Enlarged view of EBS around* Γ *for MgB2 using LDA functional and* Δ*k = 0.018 Å−1 showing (a) degenerate*  σ *bands at equilibrium (blue lines) and (b) after atom displacement Dx = 0.063 Å (red lines) along the E2g mode direction; note the split of* σ *bands causing loss of degeneracy which coincides with loss of*

*DOI: http://dx.doi.org/10.5772/intechopen.96960*

**3.2 Influence of atom displacements**

EBS, can be determined [28, 36].

sonable at temperatures >40 K [28].

made with confidence.

variations due to superlattices or of order/disorder. For example, we have shown using DFT calculations with appropriate k-grid values for (Mg1-xAlx)B2 that ordered motifs with adjacent Al-layers are thermodynamically favored by ~0.15 eV over more complex, disordered configuration(s) [42]. A discrepancy of ~0.2 eV due to incorrect choice of k-grid value (**Figure 4**) does not enable such distinction to be made with confidence.


initial vorticity field
for i = 2:nx+2 for j = 2:ny+2
w[i,j] = exp(-pi*((x[i-1]-xc1)^2 + (y[j-1]-yc1)^2)) +
exp(-pi*((x[i-1]-xc2)^2 + (y[j-1]-yc2)^2))
end end
end
```
The vortex-merger problem has the periodic domain and hence we use fast Fourier transform (FFT) Poisson solver discussed in Section 6.1.1 to get the streamfunction from vorticity field at every time step. The Julia function for FFT Poisson solver is outlined in Listing 18. The evolution of the merging process for two vortices into a single vortex is displayed in Figure 26. If we let the simulation run for some more time, we will see a single vortex getting formed.

✝ ✆

**Figure 26.** Evolution of the vorticity field at three time steps during the co-rotating vortex interaction. The solution is computed using second-order explicit solver.

We compare the computational time required for two-dimensional incompressible Navier-Stokes solver in Julia with Python code. We use two versions of Python code. In the first version, we use for loop similar to the way we write Julia code. The Python code for computing the right hand side term using Arakawa numerical scheme is given in Listing 30. The other version is the vectorized version which speeds up the code without using any loops and is given in Listing 31. In vectorization, several operations such as multiplication, addition, division are performed over a vector at the same time. From Table 3, we can easily see the benefit of Julia over Python for computationally intensive problems like the ones encountered in CFD applications.

**return** f

**Table 3.** Comparison of CPU time for Julia and Python version of Navier-Stokes solver for grid resolution *Nx* = 128 and *Ny* = 128. We note that the codes are written mostly for the pedagogical purpose and the CPU time may not be the optimal time that can be achieved for each of the programming languages.

**Listing 30.** Computation of right hand side function in Python without vectorization. ✞ ☎

```