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Authors: Seyran Naghdi

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Background: Orphan drug development is limited by very high costs attributed to the research and development and small size market. How health policymakers address this challenge to consider both supply and demand sides need to be explored for directing the policies and plans in the right way. The price is an important signal for pharmaceutical companies’ profitability and the patients’ accessibility as well. Objective: This study aims to find out the orphan drugs' price-setting patterns and approaches in health systems through a systematic review of the available evidence. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) approach was used. MedLine, Embase, and Web of Sciences were searched via appropriate search strategies. Through Medical Subject Headings (MeSH), the appropriate terms for pricing were 'cost and cost analysis', and it was 'orphan drug production', and 'orphan drug', for orphan drugs. The critical appraisal was performed by the Joanna-Briggs tool. A Cochrane data extraction form was used to obtain the data about the studies' characteristics, results, and conclusions. Results: Totally, 1,197 records were found. It included 640 hits from Embase, 327 from Web of Sciences, and 230 MedLine. After removing the duplicates, 1,056 studies remained. Of them, 924 studies were removed in the primary screening phase. Of them, 26 studies were included for data extraction. The majority of the studies (>75%) are from developed countries, among them, approximately 80% of the studies are from European countries. Approximately 85% of evidence has been produced in the recent decade. Conclusions: There is a huge variation of price-setting among countries, and this is related to the specific pharmacological market structure and the thresholds that governments want to intervene in the process of pricing. On the other hand, there is some evidence on the availability of spaces to reduce the very high costs of orphan drugs development through an early agreement between pharmacological firms and governments. Further studies need to focus on how the governments could incentivize the companies to agree on providing the drugs at lower prices.

Keywords: orphan drugs, orphan drug production, pricing, costs, cost analysis

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Authors: Tania Camarillo Contreras, Yana Kuchirko

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Women’s sexuality, despite it being a core part of human functioning, has historically been stigmatized, silenced, and regulated and silenced across many cultures. The regulation of women’s bodies and desires has often been accomplished via gender ideologies and norms that ascribe power to men over women. Within Latino communities, gender ideologies like marianismo provide scripts by which women are expected to adhere submissiveness, purity, and putting others’ needs before their own. Prior work on sexuality-related topics among Latinas has almost exclusively examined the roles of risky behavior, partner violence, and gender roles on psychological and health outcomes. it know little about positive aspects of Latinas’ sexuality, such as their perspectives on sexual excitation and inhibition. Moreover, we know little about Latina’s sexuality in relation to marianismo. In this study, it ask the following questions (1) What are Latina’s perspectives on sexual excitation/inhibition? Do they vary by demographic variables (e.g., education, religiosity); (2) Does endorsement of marianismo among Latina women predict their perspectives on sexual excitation/sexual inhibition? and (3) Does endorsement of double standard (mediator variable) mediate the relation between marianismo (Independent) and sexual excitation/sexual inhibition? The results of this study shed light on effects of culturally specific gender ideologies like marianismo on women’s sexualities and have implications for culturally informed and gender-affirming policies seeking to better support Latinas’ sexual health.

Keywords: cultural beliefs, latinas, marianismo, sexuality, sexual inhibition

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Authors: E. K. Linsenmayer

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Traditional international relations theorists define state security, the principal national interest, as a state’s military force. However, many political theorists argue the current definition of security is not comprehensive and therefore, problematic. This paper argues that women’s physical security is not only linked but also necessary to achieve state security. In today’s unipolar political international system, the United States continues to accredit national security to its military. However, in one of the most militarized countries, women remain insecure. Through a case study method of the United States, this paper illuminates a necessary political prescription: the empowerment of women through an inside-out, feminist theoretical approach that makes state security attainable. The research through empirical testing, drawing from several databases, shows the positive effects of women’s physical security on state security. Women’s physical security is defined in terms of equal legal practices, health, education, and female representation in the government. State security is measured by the relative peace of a state, its involvement in conflict and a state’s relations with neighboring states. This paper shows that empowering women, 50% of the world’s population, is necessary for ending the current vicious circle of militarization, war, and insecurity. Without undoing gender power dynamics at the individual and societal level, security at all levels remains unattainable.

Keywords: gender inequality, politics, state security, women's security

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Authors: Ziba Khalili, Mohsen Sheikholeslami, Ladan Momayez

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Combining the photovoltaic/thermal (PVT) systems with a thermoelectric (TE) module can raise energy yields since the TE module boosts the system's energy conversion efficiency. In the current study, a PVT system integrated with a TE module was designed and simulated in ANSYS Fluent 19.2. A copper heat transfer tube (HTT) was employed for cooling the photovoltaic (PV) cells. Four different shapes of HTT cross-section, i.e., circular, square, elliptical, and triangular, with equal cross-section areas were investigated. Also, the influence of Cu-Al2O3/water hybrid nanofluid (0.024% volume concentration), fluid inlet velocity (uᵢ ), and amount of solar radiation (G), on the PV temperature (Tₚᵥ) and system performance were investigated. The ambient temperature (Tₐ), wind speed (u𝓌), and fluid inlet temperature (Tᵢ), were considered to be 25°C, 1 m/s, and 27°C, respectively. According to the obtained data, the triangular case had the greatest impact on reducing the compared to other cases. In the triangular case, examination of the effect of hybrid nanofluid showed that the use of hybrid nanofluid at 800 W/m2 led to a reduction of the TPV by 0.6% compared to water, at 0.19 m/s. Moreover, the thermal efficiency ( ) and the overall electrical efficiency (nₜ) of the system improved by 0.93% and 0.22%, respectively, at 0.19 m/s. In a triangular case where G and were 800 W/m2 and 19 m/s, respectively, the highest amount of, thermal power (Eₜ), and, were obtained as 72.76%, 130.84 W and 12.03%, respectively.

Keywords: electrical performance, photovoltaic/thermal, thermoelectric, hybrid nanofluid, thermal efficiency

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Authors: A. Bajek, J. Skopinska-Wisniewska, A. Rynkiewicz, A. Jundzill, M. Bodnar, A. Marszalek, T. Drewa

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Traumatic injury and age-related degenerative diseases associated with cartilage are major health problems worldwide. The articular cartilage is comprised of a relatively small number of cells, which have a relatively slow rate of turnover. Therefore, damaged articular cartilage has a limited capacity for self-repair. New clinical methods have been designed to achieve better repair of injured cartilage. However, there is no treatment that enables full restoration of it. The aim of this study was to evaluate how collagen gel with bone marrow mesenchymal stem cells (MSCs) and collagen gel alone will influence on the hip cartilage repair after injury. Collagen type I was isolated from rats’ tails and cross-linked with N-hydroxysuccinimide in 24-hour process. MSCs were isolated from rats’ bone marrow. The experiments were conducted according to the guidelines for animal experiments of Ethics Committee. Fifteen 8-week-old Wistar rats were used in this study. All animals received hip joint surgery with a total of 30 created cartilage defects. Then, animals were randomly divided into three groups and filled, respectively, with collagen gel (group 1), collagen gel cultured with MSCs (group II) or left untreated as a control (control group). Immunohistochemy and radiological evaluation was carried out 11 weeks post implantation. It has been proved that the surface of the matrix is non-toxic, and its porosity promotes cell adhesion and growth. However, the in vivo regeneration process was poor. We observed the low integration rate of biomaterial. Immunohistochemical evaluation of cartilage after 11 weeks of treatment showed low II and high X collagen expression in two tested groups in comparison to the control one, in which we observed the high II collagen expression. What is more, after radiological analysis, we observed the best regeneration process in control group. The biomaterial construct and mesenchymal stem cells, as well as the use of the biomaterial itself was not sufficient to regenerate the hip cartilage surfaces. These results suggest that the collagen gel based biomaterials, even with MSCs, are not satisfactory in repar of hip cartilage defect. However, additional evaluation is needed to confirm these results.

Keywords: collafen gel, MSCs, cartilage repair, hip cartilage

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Authors: Md. Rifad Chowdhury

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This research study investigates employees' conception of work motivation to perform at the municipal corporation in Bangladesh. The municipal corporation is one of the key administrative bodies of Bangladesh’s local government. Municipal corporation employees provide essential public services in the country’s semi-urban areas. Work motivation has been defined as a result of interaction between the individual and the environment. Local government studies indicate the work environment of the municipal corporation is unique because of its key colonial and political history, several reform attempts, non-western social perspectives, job functions, and traditional governance. The explorative purpose of this study is to find and analyse the conceptions of employees’ work motivation within this environment to expand a better understanding of work motivation. According to the purpose of this study, a qualitative method has been adopted, which has remained a very unpopular method among work motivational researchers in Bangladesh. Twenty-two semi-structured online interviews were conducted in this study. Phenomenographic research methodology has been adopted to describe the limited number of qualitatively different ways of experiencing work motivation. During the analysis of the semi-structured interview transcripts, the focus was on the employees' perspectives as employees experience work motivation or the second-order perspective to explore and analyse the conceptions. Based on the participants' collective experiences and dimensions of variation across the different ways of experiencing, six conceptions of employee work motivation to perform at the municipal corporation were identified in this study. The relationships between conceptions were further elaborated in terms of critical variations across the conceptions. Six dimensions of critical variations have emerged within and between the conceptions. In the outcome space, the relationships between conceptions and dimensions of critical variations are presented in a logical structure. The findings of this research study show significance to expand the understanding of work motivation and the research context of phenomenography. The findings of this research will contribute to the ongoing attention of contextual work motivational understanding from a Bangladeshi perspective and phenomenographic research conceptions in organisational behaviour studies.

Keywords: work motivation, qualitative, phenomenography, local government

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Authors: Shuk Ting Kinnia Yau

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As China has become more and more influential in the global and geo-political arena, mutual understanding between Japan and China has also become a topic of paramount importance. There have always been tensions between the two countries, but unfortunately, each country tends to blame the other for fanning emotions. This research will investigate portrayals of China and the Chinese people in Japanese media such as newspapers, TV news, TV drama, and cinema over this period, focusing on media sources that have particularly wide viewership or readership. By doing so, it attempts to detect any general trends in the positive or negative character of such portrayals and to see if they correlate with the results of surveys of attitudes among the general population. To the degree that correlations may be found, the question arises as to whether the media portrayals are a reflection of societal attitudes towards the Chinese, on one hand, or may be playing a role in promoting such attitudes, on the other. The relationship here is, without doubt, more complex than a simple one-way relationship of cause and effect, but indications of some direction of causality may be suggested by trends in one occurring before or after the other. Evidence will also be sought of possible longer-term trends in media portrayals of China and the Chinese people in Japan during the post-2012 period, i.e., Abe Shinzo’s second term as prime minister, in comparison to earlier periods. Perceptions of Japan’s view of China and the Chinese, both inside and outside the scholarly world, tend to be oversimplified and are often incomprehensive. This research calls attention to the role played by the media in promoting or de-promoting Sino-Japanese relations. By analyzing the nature and background of images of China and the Chinese people presented in the Japanese media, especially under the new Abe Regime, this research seeks to promote a more balanced and comprehensive understanding of attitudes in Japanese society towards its gigantic neighbor. Scholars have seen the increasingly fragile Sino-Japanese relationship as inseparable from the real-world political conflicts that have become more frequent in recent years and have sought to draw a correlation between the two. The influence of the media, however, remains a mostly under-explored domain in the academic world. Against this background, this research aims to provide an enriched scholarly understanding of Japan’s perception of China by investigating to what extent such perception can be seen to be affected by subjective or selective forms of presentation of China found in the Japanese media, or vice versa.

Keywords: Abe Shinzo, China, Japan, media

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Authors: Shannon Hearney, Jeffrey Hoch

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While all cancers are costly to treat, pancreatic cancer is a notoriously costly and deadly form of cancer. Across the world there are a variety of treatment centers ranging from small clinics to large, high-volume hospitals as well as differing structures of payment and access. It has been noted that centers that treat a high volume of pancreatic cancer patients have higher quality of care, it is unclear if that care is cost-effective. In the US there is no clear consensus on the cost-effectiveness of high-volume centers for the surgical care of pancreatic cancer. Other European countries, like Finland and Italy have shown that high-volume centers have lower mortality rates and can have lower costs, there however, is still a gap in knowledge about these centers cost-effectiveness globally. This paper seeks to review the current literature in Europe and the US to gain a better understanding of the state of high-volume pancreatic surgical centers cost-effectiveness while considering the contextual differences in health system structure. A review of major reference databases such as Medline, Embase and PubMed will be conducted for cost-effectiveness studies on the surgical treatment of pancreatic cancer at high-volume centers. Possible MeSH terms to be included, but not limited to, are: “pancreatic cancer”, “cost analysis”, “cost-effectiveness”, “economic evaluation”, “pancreatic neoplasms”, “surgical”, “Europe” “socialized medicine”, “privatized medicine”, “for-profit”, and “high-volume”. Studies must also have been available in the English language. This review will encompass European scientific literature, as well as those in the US. Based on our preliminary findings, we anticipate high-volume hospitals to provide better care at greater costs. We anticipate that high-volume hospitals may be cost-effective in different contexts depending on the national structure of a healthcare system. Countries with more centralized and socialized healthcare may yield results that are more cost-effective. High-volume centers may differ in their cost-effectiveness of the surgical care of pancreatic cancer internationally especially when comparing those in the United States to others throughout Europe.

Keywords: cost-effectiveness analysis, economic evaluation, pancreatic cancer, scientific literature review

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Authors: Balasooriya B. M. C. M., Sujeeva N., Thowfeek Z., Siddiqa Omo, Liyanagunawardana J. E., Jayawardana Saiu, Manathunga S. S., Katulanda G. W.

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Introduction and objectives: Adrenal venous sampling (AVS) is the gold standard to discriminate unilateral primary aldosteronism (UPA) from bilateral disease (BPA). AVS is technically demanding and only performed in a limited number of centers worldwide. To the best of our knowledge, Except for one study conducted in India, no other research studies on this area have been conducted in South Asia. This study aimed to evaluate the effectiveness of AVS in the management of primary aldosteronism. Methods: A total of 32 patients who underwent AVS at the National Hospital of Sri Lanka from April 2021 to April 2023 were enrolled. Demographic, clinical and laboratory data were obtained retrospectively. A procedure was considered successful when adequate cannulation of both adrenal veins was demonstrated. Cortisol gradient across the adrenal vein (AV) and the peripheral vein was used to establish the success of venous cannulation. Lateralization was determined by the aldosterone gradient between the two sides. Continuous and categorical variables were summarized with mean, SD, and proportions, respectively. The mean and standard deviation of the contralateral suppression index (CSI) were estimated with an intercept-only Bayesian inference model. Results: Of the 32 patients, the average age was 52.47 +26.14 and 19 (59.4%) were males. Both AVs were successfully cannulated in 12 (37.5%). Among them, lateralization was demonstrated in 11(91.7%), and one was diagnosed as a bilateral disease. There were no total failures. Right AV cannulation was unsuccessful in 18 (56.25%), of which lateralization was demonstrated in 9 (50%), and others were inconclusive. Left AV cannulation was unsuccessful only in 2 (6.25%); one was lateralized, and the other remained inconclusive. The estimated mean of the CSI was 0.33 (89% credible interval 0.11-0.86). Seven patients underwent unilateral adrenalectomy and demonstrated significant improvement in blood pressure during follow-up. Two patients await surgery. Others were treated medically. Conclusions: Despite failure due to procedural difficulties, AVS remained useful in the management of patients with PA. Moreover, the success of the procedure needs experienced hands and advanced equipment to achieve optimal outcomes in PA.

Keywords: adrenal venous sampling, lateralization, contralateral suppression index, primary aldosteronism

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Authors: Betty Kibirige

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Students entering the University of Zululand (UNIZULU) Science Faculty mostly come with skills that allow them to prepare for exams and pass them in order to satisfy requirements for entry into a tertiary Institution. Some students hail from deep rural schools with limited facilities, while others come from well-resourced schools. Personal experience has shown that it may take a student the whole time at a tertiary institution following the same skills as those acquired in high school as a sure means of entering the next level in their development, namely a postgraduate program. While it is apparent that at this point in human history, it is totally impossible to teach all the possible content in any one subject, many academics approach teaching and learning from the traditional point of view. It therefore became apparent to explore ways of developing a graduate that will be able to approach life with skills that allows them to navigate knowledge by applying conceptual and critical thinking skills. Recently, the Science Faculty at the University of Zululand introduced two Engineering programs. In an endeavour to approach the development of the Engineering graduate in this institution to be able to tackle problem-solving in the present-day excessive information availability, it became necessary to study and review approaches used by various academics in order to settle for a possible best approach to the challenge at hand. This paper focuses on the development of a deep rural child in a graduate with conceptual and critical thinking skills as major attributes possessed upon graduation. For this purpose, various approaches were studied. A combination of these approaches was repackaged to form an approach that may appear novel to UNIZULU and the rural child, especially for the Engineering discipline. The approach was checked by offering quiz questions to students participating in an engineering module, observing test scores in the targeted module and make comparative studies. Test results are discussed in the article. It was concluded that students’ graduate attributes could be tailored subconsciously to indeed include conceptual and critical thinking skills, but through more than one approach depending mainly on the student's high school background.

Keywords: graduate attributes, conceptual skills, critical thinking skills, traditional approach

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Authors: Torben Hansen

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While trust has long been regarded as one of the most critical variables for developing and maintaining well-functioning financial customer-seller relationships it can be suggested that trust not only relates to customer trust in individual companies (narrow-scope trust). Trust also relates to the broader business context in which consumers may carry out their financial behaviour (broad-scope trust). However, despite the well-recognized significance of trust in marketing research, only few studies have investigated the role of broad-scope trust in consumer financial behaviour. Moreover, as one of its many serious outcomes, the global financial crisis has elevated the need for an improved understanding of the role of broad-scope trust in consumer financial services markets. Only a minority of US and European consumers are currently confident in financial companies and ‘financial stability’ and ‘trust’ are now among the top reasons for choosing a bank. This research seeks to address this shortcoming in the marketing literature by investigating direct and moderating effects of broad-scope trust on consumer financial behaviour. Specifically, we take an ability-effort approach to consumer financial behaviour. The ability-effort approach holds the basic premise that the quality of consumer actions is influenced by ability factors, for example consumer knowledge and cognitive effort. Our study is based on two surveys. Survey 1 comprises 1,155 bank consumers, whereas survey 2 comprises 764 pension consumers. The results indicate that broad-scope trust negatively moderates relationships between knowledge and financial healthiness and between cognitive effort and financial healthiness. In addition, it is demonstrated that broad-scope trust negatively influences cognitive effort. Specifically, the results suggest that broad-scope trust contributes to the financial well-being of consumers with limited financial knowledge and processing capabilities. Since financial companies are dependent on customers to pay their loans and bills they have a greater interest in developing relations with consumers with a healthy financial behaviour than with the opposite. Hence, financial managers should be engaged with monitoring and influencing broad-scope trust. To conclude, by taking into account the contextual effect of broad-scope trust, the present study adds to our understanding of knowledge-effort-behaviour relationship in consumer financial markets.

Keywords: cognitive effort, customer-seller relationships, financial healthiness, knowledge, trust

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Authors: Mardin Abdalqadir, Paul Adzakro, Tannaz Pak, Sina Rezaei Gomari

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Climate change and global warming recently became significant concerns due to the massive emissions of greenhouse gases into the atmosphere, predominantly CO2 gases. Therefore, it is necessary to find sustainable and inexpensive methods to capture the greenhouse gasses and protect the environment for live species. The application of naturally available and cheap adsorbents of carbon such as clay minerals became a great interest. However, the minerals prone to low storage capacity despite their high affinity to adsorb carbon. This paper aims to explore ways to improve the pore volume and surface area of two selected clay minerals, ‘montmorillonite and kaolinite’ by acid treatment to overcome their low storage capacity. Montmorillonite and kaolinite samples were treated with different sulfuric acid concentrations (0.5, 1.2 and 2.5 M) at 40 °C for 8 hours to achieve the above aim. The grain size distribution and morphology of clay minerals before and after acid treatment were explored with Scanning Electron Microscope to evaluate surface area improvement. The ImageJ software was used to find the porosity and pore volume of treated and untreated clay samples. The structure of the clay minerals was also analyzed using an X-ray Diffraction machine. The results showed that the pore volume and surface area were increased substantially through acid treatment, which speeded up the rate of carbon dioxide adsorption. XRD pattern of kaolinite did not change after sulfuric acid treatment, which indicates that acid treatment would not affect the structure of kaolinite. It was also discovered that kaolinite had a higher pore volume and porosity than montmorillonite before and after acid treatment. For example, the pore volume of untreated kaolinite was equal to 30.498 um3 with a porosity of 23.49%. Raising the concentration of acid from 0.5 M to 2.5 M in 8 hours’ time reaction led to increased pore volume from 30.498 um3 to 34.73 um3. The pore volume of raw montmorillonite was equal to 15.610 um3 with a porosity of 12.7%. When the acid concentration was raised from 0.5 M to 2.5 M for the same reaction time, pore volume also increased from 15.610 um3 to 20.538 um3. However, montmorillonite had a higher specific surface area than kaolinite. This study concludes that clay minerals are inexpensive and available material sources to model the realistic conditions and apply the results of carbon capture to prevent global warming, which is one of the most critical and urgent problems in the world.

Keywords: acid treatment, kaolinite, montmorillonite, pore volume, porosity, surface area

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Authors: Stefano Ruggieri, Rubinia C. Bonfanti

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Research on leadership in sports organizations has proved extremely fruitful in recent decades, favoring the growing and diffusion of figures such as mental coaches, trainers, etc. Recent scholarly attention on organizations has been directed towards the phenomenon of leader self-sacrifice, wherein leaders who display such behavior are perceived by their followers as more effective, charismatic, and legitimate compared to those who prioritize self-interest. This growing interest reflects the importance of leaders who prioritize the collective welfare over personal gain, as they inspire greater loyalty, trust, and dedication among their followers, ultimately fostering a more cohesive and high-performing team environment. However, there is limited literature on the mechanisms through which self-sacrifice influences both group dynamics (such as cohesion and team identification) and individual factors (such as self-competence). The aim of the study is to analyze the impact of the leader self-sacrifice on cohesion, team identification and self-competence. Team identification is a crucial determinant of individual identity, delineated by the extent to which a team member aligns with a specific organizational team rather than broader social collectives. This association motivates members to synchronize their actions with the collective interests of the group, thereby fostering cohesion among its constituents, and cultivating a shared sense of purpose and unity within the team. In the domain of team sports, particularly soccer and water polo, two studies involving 447 participants (men = 238, women = 209) between 22 and 35 years old (M = 26.36, SD = 5.51) were conducted. The first study employed a correlational methodology to investigate the predictive capacity of self-sacrifice on cohesion, team identification, self-efficacy, and self-competence. The second study utilized an experimental design to explore the relationship between team identification and self-sacrifice. Together, these studies provided comprehensive insights into the multifaceted nature of leader self-sacrifice and its profound implications for group cohesion and individual well-being within organizational settings. The findings underscored the pivotal role of leader self-sacrifice in not only fostering stronger bonds among team members but also in enhancing critical facets of group dynamics, ultimately contributing to the overall effectiveness and success of the team.

Keywords: cohesion, leadership, self-sacrifice, sports organizations, team-identification

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Authors: Samipraj Mishra

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Despite the successful implementation of community forestry program, a number of pros and cons have been raised on Terai community forestry in the case of lowland locally called Terai region of Nepal, which is climatically belongs to tropical humid and possessed high quality forests in terms of ecology and economy. The study aims to investigate the local pricing strategy of forest products and its impacts on equitable forest benefit sharing, collection of community fund and carrying out livelihood improvement activities. The study was carried out on six community forests revealed that local people have substantially benefited from the community forests. However, being the region is heterogeneous by socio-economic conditions and forest resources have higher economical potential, the decision of low pricing strategy made by the local people have created inequality problems while sharing the forest benefits, and poorly contributed to community fund collection and consequently carrying out limited activities of livelihood improvement. The paper argued that the decision of low pricing strategy of forest products is counter-productive to promote the equitable benefit sharing in the areas of heterogeneous socio-economic conditions with high value forests. The low pricing strategy has been increasing accessibility of better off households at higher rate than poor; as such households always have higher affording capacity. It is also defective to increase the community fund and carry out activities of livelihood improvement effectively. The study concluded that unilateral decentralized forest policy and decision-making autonomy to the local people seems questionable unless their decision-making capacities are enriched sufficiently. Therefore, it is recommended that empowerment of decision-making capacity of local people and their respective institutions together with policy and program formulation are prerequisite for efficient and equitable community forest management and its long-term sustainability.

Keywords: community forest, livelihood, socio-economy, pricing system, Nepal

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Authors: Karina Lõbus, Silver Muld, Kadri Kööp, Mare Tupits

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Aim: The aim of the research is to describe the experiences and needs of fathers’ of children with cancer in coping with the child's disease. Background: Today, about 80% of children diagnosed with malignancy in developed countries survive. Despite the positive statistics, recovery is not always certain, treatment is often very intensive and long-term. Cancer is affecting an increasing number of the population, which is increasing the demand for quality care, but the nature of expected care is currently unclear. This topic is important for the development of professional practice, as nurses complain that their knowledge to deal with the relatives of a patient with a difficult diagnosis is limited and would therefore like additional information to deal with the situation. Design: Qualitative, empirical, descriptive research. Method: The data were collected through semi-structured interviews and analysed by inductive content analysis method. Interviews were conducted during Autumn 2020. 4 subjects participated in the research. Results and Conclusions: The thesis revealed that fathers had different experiences and needs in dealing with the child's illness. Fathers' experiences of coping with child's diseases encompassed experiences with information, social relationships, healthcare, changes in personal health and experiences regarding the child. Regarding information, the respondents pointed out bad experiences with the availability of information and the ability to convey the necessary information. Experiences regarding social relationships included experiences with relatives and strangers. Regarding healthcare, fathers mentioned experiences related to the child's health and healthcare professionals. In regards to personal health, fathers pointed out negative changes in their mental and physical health. In relation to the child, the subjects revealed experiences regarding changed values, way of life and raising the child. According to the research, fathers’ needs in relation to dealing with child's cancer included material, social, and spiritual needs. In regard to material needs, fathers pointed out the need for state assistance and the needs related to the surrounding environment. The needs concerning social belonging involved needs for a driving force and involvement in the treatment process. Regarding spiritual needs, fathers expressed mixed feelings towards the need for outside and professional help.

Keywords: father, coping, cancer, child, experience, need

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Authors: Hyun-Soo Seol, In-Gun Kim, Hyun Seok Hong, Dong-Woo Kang, Ju Lee

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Rotor of Spoke-Type PMSM is divided into permanent magnet and rotor core. Moreover, rotor core is composed of pole-piece, Bridge and rib. Piece between the permanent magnet N and S poles is pole-piece. Bridge and rib hold pole-piece. In the case of pole-piece and bridge, it is essential structure of Spoke-Type PMSM. However, Rib can be selected by the designer depending on the operating conditions and constraints. If rib is present in the rotor, rib which acts in the leak path generates a leakage flux. Although the leakage flux reduces the torque in low speed, it expands speed range in high speed. So, there is a relationship of trade off. Viewed from the standpoint of permanent magnet demagnetization, since the magnetic flux by the stator winding leaks to the rib, it is an advantage. In addition, rib affects the safety factor of the rotor. For application required high speed operation, since the securing the safety factor of the rotor is important, rib structure is advantageous. On the other hand, in the case of the application that does not require high speed operation, it is desirable to increase the output power by designing without rib. In this paper, Effects on rib structure is analyzed in detail and this paper provides designer with information about rotor design of spoke-type PMSM according to rib structure.

Keywords: spoke-Type PMSM, rotor shape, rib, operation range

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Authors: Elizabeth Carthy

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There is growing recognition that sexual exploitation and abuse (SEA) perpetrated by humanitarian workers is widespread, most recently affirmed by allegations of high-ranking Oxfam officials paying women for sex in post-earthquake Haiti. SEA covers a range of gendered abuses, including rape, sexual assault, and ‘transactional’ or ‘survival’ sex. Holding individuals legally accountable for such behaviors is difficult in all contexts even more so in fragile and conflict-affected settings. Transactional sex, for the purposes of this paper, refers to situations where humanitarian workers exchange aid or assistance for sexual services. This paper explores existing organizational accountability measures relating to transactional sex engaged in by international humanitarian workers through a descriptive and interpretive case study approach-examining the situation in Haiti. It comparatively analyses steps the United Nations has taken to combat this problem. Then it examines the possibility of domestic legal accountability for such conduct in Haiti. Finally, the paper argues that international human rights law can fill in potential gaps in domestic legal frameworks to ensure states hold humanitarian workers and potentially organizations accountable for engaging in and/or perpetuating this gendered abuse of power.

Keywords: gender-based violence, humanitarian action, international human rights law, sexual exploitation

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Authors: Mohammadreza Akbari, Pooya Soleimani Besheli, Reza khalili, Sara Akbari, Davood Domiri Ganji

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In this symposium, our aims are accuracy, capabilities and power at solving of the complicate non-linear differential at the reaction chemical in the catalyst reactor (heterogeneous reaction). Our purpose is to enhance the ability of solving the mentioned nonlinear differential equations at chemical engineering and similar issues with a simple and innovative approach which entitled ‘’Akbari-Ganji's Method’’ or ‘’AGM’’. In this paper we solve many examples of nonlinear differential equations of chemical reactions and its investigate. The chemical reactor with the energy changing (non-isotherm) in two reactors of mixed and plug are separately studied and the nonlinear differential equations obtained from the reaction behavior in these systems are solved by a new method. Practically, the reactions with the energy changing (heat or cold) have an important effect on designing and function of the reactors. This means that possibility of reaching the optimal conditions of operation for the maximum conversion depending on nonlinear nature of the reaction velocity toward temperature, results in the complexity of the operation in the reactor. In this case, the differential equation set which governs the reactors can be obtained simultaneous solution of mass equilibrium and energy and temperature changing at concentration.

Keywords: new method (AGM), nonlinear differential equation, tubular and mixed reactors, catalyst bed

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Authors: Mohammad-Ali Latifi, Harry Bouwman

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Changes in the business environment accelerated dramatically over the last decades as a result of changes in technology, regulation, market, and competitors’ behavior. Firms need to change the way they do business in order to survive or maintain their growth. Innovating business model (BM) can create competitive advantages and enhance firm performance. However, many companies fail to achieve expected outcomes in practice, mostly due to irreversible fundamental changes in key components of the company’s BM. This leads to more ambiguity, uncertainty, and risks associated with business performance. However, the relationship among BM Innovation, moderating factors, and the firm’s overall performance is by and large ignored in the current literature. In this study, we identified twenty moderating factors from our comprehensive literature review. We categorized these factors based on two criteria regarding the extent to which: the moderating factors can be controlled and managed by firms, and they are generic or specific changes to the firms. This leads to four moderation groups. The first group is BM implementation, which includes management support, employees’ commitment, employees’ skills, communication, detailed plan. The second group is called BM practices, which consists of BM tooling, BM experimentation, the scope of change, speed of change, degree of novelty. The third group is Firm characteristics, including firm size, age, and ownership. The last group is called Industry characteristics, which considers the industry sector, competitive intensity, industry life cycle, environmental dynamism, high-tech vs. low-tech industry. Through collecting data from 508 European small and medium-sized enterprises (SMEs) and using the structural equation modeling technique, the developed moderation model was examined. Results revealed that all factors highlighted through these four groups moderate the relation between BMI and firm performance significantly. Particularly, factors related to BM-Implementation and BM-Practices are more manageable and would potentially improve firm overall performance. We believe that this result is more important for researchers and practitioners since the possibility of working on factors in Firm characteristics and Industry characteristics groups are limited, and the firm can hardly control and manage them to improve the performance of BMI efforts.

Keywords: business model innovation, firm performance, implementation, moderation

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Authors: Omar Asad Ahmad, Mohammed Awwad

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Concrete is one of the essential elements that used in different types of construction these days, but it has many problems when interacts with environmental elements such as water, air, temperature, dust, and humidity. Also concrete made with Portland cement has certain characteristics: it is relatively strong in compression but weak in tension and tends to be brittle. These disadvantages make concrete limited to use in certain conditions. The most common problems appears on concrete are manifested by tearing, cracking, corrosion and spalling, which will lead to do some defect in concrete then in the whole construction, The fundamental objective of this research was to provide information about the hardened properties of concrete achieved by using easily available local raw materials in Jordan to support the practical work with partners in assessing the practicability of the mixes with polypropylene, and to facilitate the introduction of polypropylene fiber concrete (PFC) technology into general construction practice. Investigate the effect of the polypropylene fibers in PCC mixtures and on materials properties such as compressive strength, and tensile strength. Also to investigate the use of polypropylene fibers in plain cubes and cylindrical concrete to improve its compressive and tensile strengths to reduce early cracking and inhibit later crack growth. Increasing the hardness of concrete in this research is the main purpose to measure the deference of compressive strength and tensile strength between plain concrete and concrete mixture with polypropylene fibers different additions and to investigate its effect on reducing the early and later cracking problem. To achieve the goals of research 225 concrete test sample were prepared to measure it’s compressive strength and tensile strength, the concrete test sample were three classes (A,B,C), sub-classified to standard , and polypropylene fibers added by the volume of concrete (5%, 10%, 15%, and 20%). The investigation of polypropylene fibers mixture with concrete shows that the strengths of the cement are increased and the cracking decreased. The results show that for class A the recommended addition were 5% of polypropylene fibers additions for compressive strength and 10 % for tensile strength revels the best compressive strength that reach 26.67 Mpa and tensile strength that reach 2.548 Mpa records. Achieved results show that for classes B and C the recommend additions were 10 % polypropylene fibers revels the best compressive strength records where they reach 21.11 and 33.78 Mpa, records reach for tensile strength 2.707 and 2.65 Mpa respectively.

Keywords: polypropylene, effects, compressive, tensile, strengths, concrete, construction

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Authors: Edoba Bright Omoregie

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Nigeria became a federation in 1954 six years before it gained independence away from British colonial rule. The country has remained a federation since then despite the challenging circumstances of military rule and civil strife which have tasked its federal credentials. Since 1961, when it first decided a federalism dispute, cases over vertical and horizontal powers have inundated the country’s Supreme Court. In its current practice of federalism after democratic rule was resumed in 1999, the country has witnessed a spell of intergovernmental disputes over a good number of federalism issues. Such conflicts have eventually found their way to the Supreme Court for resolution, not as a final appellate court (which it is in other non-federal matters) but as a court of first and final instance following the constitutional provision granting the court such power. However, in April 2014 one of such disputes was denied hearing by the court when it declined original jurisdiction to determine the matter. The suit was instituted by one state of the federation against the federal government and the other 35 states challenging the collection of value added tax (a consumption tax)on certain goods and services within the state. The paper appraises the rationale of the court’s decision and reason that its decision to decline jurisdiction is the result of an avoidable misunderstanding of the dual sovereignty instituted by the federal system of Nigeria as well as a misconception of the role which the court is constitutionally assigned to play in resolving intergovernmental schisms in the federal system.

Keywords: dual sovereignty, federalism, intergovernmental conflict, Supreme Court

Procedia PDF Downloads 541

Authors: Nwogiji Cletus Olando, Oselebe Happiness Ogba, Enoch Achigan-Dako

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Digitaria iburua, commonly known as black fonio, is a cereal crop native to Africa and extensively cultivated by smallholder farmers in Northern Benin, Togo, and Nigeria. This crop holds immense nutritional and socio-cultural value. Unfortunately, limited knowledge about its genetic diversity exists due to a lack of scientific attention. As a result, its potential for improvement in food and agriculture remains largely untapped. To address this gap, a study was conducted using 41 accessions of D. iburua stored in the genebank of the Laboratory of Genetics, Biotechnology, and Seed Science at Abomey-Calavi University, Benin. The study employed both morphological and simple sequence repeat (SSR) markers to evaluate the genetic variability of the accessions. Agro-morphological assessments were carried out during the 2020 cropping season, utilizing an alpha lattice design with three replications. The collected data encompassed qualitative and quantitative traits. Additionally, molecular variability was assessed using eleven SSR markers. The results revealed significant phenotypic variability among the evaluated accessions, leading to their classification into three main clusters. Furthermore, the eleven SSR markers identified a total of 50 alleles, averaging 4.55 alleles per locus. The primers exhibited an average polymorphic information content value of 0.43, with the DE-ARC019 primer displaying the highest value (0.59). These findings suggest a substantial degree of genetic heterogeneity within the evaluated accessions, and the SSR markers employed in the study proved highly effective in detecting and characterizing this genetic variability. In conclusion, this study highlights the presence of significant genetic diversity in black fonio and provides valuable insights for future efforts aimed at its genetic improvement and conservation.

Keywords: genetic diversity, digitaria iburua, genetic improvement, simple sequence repeat markers, Nigeria, conservation

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Authors: Ataollah Rabiee1, Amir Hossein Kamalinia, Alireza Atf

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One of the most important issues in the design of nuclear fusion power plants is the heat removal from the hottest region at the diverter. Various methods could be employed in order to improve the heat transfer efficiency, such as generating turbulent flow and injection of nanoparticles in the host fluid. In the current study, Water/AL₂O₃ nanofluid forced swirl flow boiling has been investigated by using a homogeneous thermophysical model within the Eulerian-Eulerian framework through a twisted tape tube, and the boiling phenomenon was modeled using the Rensselaer Polytechnic Institute (RPI) approach. In addition to comparing the results with the experimental data and their reasonable agreement, it was evidenced that higher flow mixing results in more uniform bulk temperature and lower wall temperature along the twisted tape tube. The presence of AL₂O₃ nanoparticles in the boiling flow field showed that increasing the nanoparticle concentration leads to a reduced vapor volume fraction and wall temperature. The Computational fluid dynamics (CFD) results show that the average heat transfer coefficient in the tube increases both by increasing the nanoparticle concentration and the insertion of twisted tape, which significantly affects the thermal field of the boiling flow.

Keywords: nanoparticle, boiling, CFD, two phase flow, alumina, ITER

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Authors: Elena Carcano, Mirzi Betasolo

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This study helps Public Water Bureaus in giving reliable answers to water concession requests. Rapidly increasing water requests can be supported provided that further uses of a river course are not totally compromised, and environmental features are protected as well. Strictly speaking, a water concession can be considered a continuous drawing from the source and causes a mean annual streamflow reduction. Therefore, deciding if a water concession is appropriate or inappropriate seems to be easily solved by comparing the generic demand to the mean annual streamflow value at disposal. Still, the immediate shortcoming for such a comparison is that streamflow data are information available only for few catchments and, most often, limited to specific sites. Subsequently, comparing the generic water demand to mean daily discharge is indeed far from being completely satisfactory since the mean daily streamflow is greater than the water withdrawal for a long period of a year. Consequently, such a comparison appears to be of little significance in order to preserve the quality and the quantity of the river. In order to overcome such a limit, this study aims to complete the information provided by flow duration curves introducing a link between Flow Duration Curves (FDCs) and recession curves and aims to show the chronological sequence of flows with a particular focus on low flow data. The analysis is carried out on 25 catchments located in North-Eastern Italy for which daily data are provided. The results identify groups of catchments as hydrologically homogeneous, having the lower part of the FDCs (corresponding streamflow interval is streamflow Q between 300 and 335, namely: Q(300), Q(335)) smoothly reproduced by a common recession curve. In conclusion, the results are useful to provide more reliable answers to water request, especially for those catchments which show similar hydrological response and can be used for a focused regionalization approach on low flow data. A mathematical link between streamflow duration curves and recession curves is herein provided, thus furnishing streamflow duration curves information upon a temporal sequence of data. In such a way, by introducing assumptions on recession curves, the chronological sequence upon low flow data can also be attributed to FDCs, which are known to lack this information by nature.

Keywords: chronological sequence of discharges, recession curves, streamflow duration curves, water concession

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Authors: Shilu Deepa Thomas, P. Jayaprakash, Dorota Łazewska, Katarzyna Kieć-Kononowicz, B. Sadek

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A large body of evidence suggests the involvement of cognitive impairment, increased levels of inflammation and oxidative stress in the pathogenesis of autism spectrum disorder (ASD). ASD commonly coexists with psychiatric conditions like anxiety and cognitive challenges, and individuals with ASD exhibit significant levels of inflammation and immune system dysregulation. Previous Studies have identified elevated levels of pro-inflammatory markers such as IL-1β, IL-6, IL-2 and TNF-α, particularly in young children with ASD. The current therapeutic options for ASD show limited effectiveness, signifying the importance of exploring an efficient drugs to address the core symptoms. The role of histamine H3 receptors (H3Rs) in memory and the prospective role of H3R antagonists in pharmacological control of neurodegenerative disorders, e.g., ASD, is well-accepted. Hence, the effects of chronic systemic administration of H3R antagonist E159 on autistic-like repetitive behaviors, social deficits, memory and anxiety parameters, as well as neuroinflammation in Black and Tan BRachyury (BTBR) mice, were evaluated using Y maze, Barnes maze, self-grooming, open field and three chamber social test. E159 (2.5, 5 and 10 mg/kg, i.p.) dose-dependently ameliorated repetitive and compulsive behaviors by reducing the increased time spent in self-grooming and improved reduced spontaneous alternation in BTBR mice. Moreover, treatment with E159 attenuated disturbed anxiety levels and social deficits in tested male BTBR mice. Furthermore, E159 attenuated oxidative stress by significantly increasing GSH, CAT, and SOD and decreasing the increased levels of MDA in the cerebellum as well as the hippocampus. In addition, E159 decreased the elevated levels of proinflammatory cytokines (tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and IL-6). The observed results show that H3R antagonists like E159 may represent a promising novel pharmacological strategy for the future treatment of ASD.

Keywords: histamine H3 receptors, antagonist E159, autism, behaviors, mice

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Authors: R. Bennai, H. Ait Atmane, Jr., A. Tounsi

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In this work, a new analytical approach using a refined theory of hyperbolic shear deformation of a beam was developed to study the free vibration of graduated sandwiches beams under different boundary conditions. The effects of transverse shear strains and the transverse normal deformation are considered. The constituent materials of the beam are supposed gradually variable depending the height direction based on a simple power distribution law in terms of the volume fractions of the constituents; the two materials with which we worked are metals and ceramics. The core layer is taken homogeneous and made of an isotropic material; while the banks layers consist of FGM materials with a homogeneous fraction compared to the middle layer. Movement equations are obtained by the energy minimization principle. Analytical solutions of free vibration and buckling are obtained for sandwich beams under different support conditions; these conditions are taken into account by incorporating new form functions. In the end, illustrative examples are presented to show the effects of changes in different parameters such as (material graduation, the stretching effect of the thickness, boundary conditions and thickness ratio - length) on the vibration free and buckling of an FGM sandwich beams.

Keywords: functionally graded sandwich beam, refined shear deformation theory, stretching effect, free vibration

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Authors: Mirzet SeHo, Alaa Alaabed, Mansur Masih

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In theory, risk-sharing-based financing (RSF) is considered a corner stone of Islamic finance. It is argued to render Islamic banks more resilient to shocks. In practice, however, this feature of Islamic financial products is almost negligible. Instead, debt-based instruments, with conventional like features, have overwhelmed the nascent industry. In addition, the framework of present-day economic, regulatory and financial reality inevitably exposes Islamic banks in dual banking systems to problems of conventional banks. This includes, but is not limited to, interest rate risk. Empirical evidence has, thus far, confirmed such exposures, despite Islamic banks’ interest-free operations. This study applies system GMM in modeling the determinants of RSF, and finds that RSF is insensitive to changes in interest rates. Hence, our results provide support to the “stability” view of risk-sharing-based financing. This suggests RSF as the way forward for risk management at Islamic banks, in the absence of widely acceptable Shariah compliant hedging instruments. Further support to the stability view is given by evidence of counter-cyclicality. Unlike debt-based lending that inflates artificial asset bubbles through credit expansion during the upswing of business cycles, RSF is negatively related to GDP growth. Our results also imply a significantly strong relationship between risk-sharing deposits and RSF. However, the pass-through of these deposits to RSF is economically low. Only about 40% of risk-sharing deposits are channeled to risk-sharing financing. This raises questions on the validity of the industry’s claim that depositors accustomed to conventional banking shun away from risk sharing and signals potential for better balance sheet management at Islamic banks. Overall, our findings suggest that, on the one hand, Islamic banks can gain ‘independence’ from conventional banks and interest rates through risk-sharing products, the potential for which is enormous. On the other hand, RSF could enable policy makers to improve systemic stability and restrain excessive credit expansion through its countercyclical features.

Keywords: Islamic banks, risk-sharing, financing, interest rate, dynamic system GMM

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Authors: David Broussard

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This review article delves into the realm of marine conservation finance, addressing the inadequacies in current financial streams from the private sector and the underutilization of existing financing mechanisms. The study emphasizes the emerging field of “blue finance”, which contributes to economic growth, improved livelihoods, and marine ecosystem health. The financial burden of marine conservation projects typically falls on philanthropists and governments, contrary to the polluter-pays principle. However, the private sector’s increasing commitment to NetZero and growing environmental and social responsibility goals prompts the need for alternative funding sources for marine conservation initiatives like marine protected areas. The article explores the potential of utilizing several financing mechanisms like carbon credits and other forms of payment for ecosystem services in the marine context, providing a solution to the lack of private funding for marine conservation. The methodology employed involves a systematic and quantitative approach, combining traditional review methods and elements of meta-analysis. A comprehensive search of the years 2000 - 2023, using relevant keywords on the Scopus platform, resulted in a review of 252 articles. The temporal evolution of blue finance studies reveals a significant increase in annual articles from 2010 to 2022, with notable peaks in 2011 and 2022. Marine Policy, Ecosystem Services, and Frontiers in Marine Science are prominent journals in this field. While the majority of articles focus on payment for ecosystem services, there is a growing awareness of the need for holistic approaches in conservation finance. Utilizing bibliometric techniques, the article showcases the dominant share of payment for ecosystem services in the literature with a focus on blue carbon. The classification of articles based on various criteria, including financing mechanisms and conservation types, aids in categorizing and understanding the diversity of research objectives and perspectives in this complex field of marine conservation finance.

Keywords: biodiversity offsets, carbon credits, ecosystem services, impact investment, payment for ecosystem services

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Authors: Junichi Hosoi

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Epidermal Langerhans cells reside in upper layer of epidermis and play a role in immune surveillance. The finding of the close association of nerve endings to Langerhans cells triggered the research on systemic regulation of Langerhans cells. They disappear from epidermis after exposure to environmental and internal stimuli and reappear about a week later. Myeloid progenitor cells are assumed to be one of the sources of Langerhans cells. We examined the effects of cortisol on the reappearance of Langerhans cells in vitro. Cord-blood derived CD34-positive cells were cultured in the medium supplemented with stem cell factor/Flt3 ligand/granulocyte macrophage-colony stimulating factor/tumor necrosis factor alpha/bone morphologic protein 7/transforming growth factor beta in the presence or absence of cortisol. Cells were analyzed by flow cytometry for CD1a (cluster differentiation 1a), a marker of Langerhans cells and dermal dendritic cells, and CD39 (cluster differentiation factor 39), extracellular adenosine triphosphatase. Both CD1a-positive cells and CD39-positive cells were decreased by treatment with cortisol (suppression by 35% and 22% compared to no stress hormone, respectively). Differentiated Langerhans cells are attracted to epidermis by chemokines that are secreted from keratinocytes. Epidermal keratinocytes were cultured in the presence or absence of cortisol and analyzed for the expression of CCL2 (C-C motif chemokine ligand 2) and CCL20 (C-C motif chemokine ligand 20), which are typical attractants of Langerhans cells, by quantitative reverse transcriptase polymerase chain reaction. The expression of both chemokines, CCL2 and CCL20, were suppressed by treatment with cortisol (suppression by 38% and 48% compared to no stress hormone, respectively). We examined the possible regulation of the suppression by cortisol with plant extracts. The extracts of Ganoderma lucidum and Iris protected the suppression of the differentiation to CD39-positive cells and also the suppression of the gene expression of LC-chemoattractants. These results suggest that cortisol, which is either systemic or locally produced, blocks the supply of epidermal Langerhans cells at 2 steps, differentiation from the precursor and attraction to epidermis. The suppression is possibly blocked by some plant extracts.

Keywords: Langerhans cell, stress, CD39, chemokine

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Authors: Sonya Barzgar, J. Patrick, A. Hettiaratchi

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Methane (CH4) is reputed as the second largest contributor to greenhouse effect with a global warming potential (GWP) of 34 related to carbon dioxide (CO2) over the 100-year horizon, so there is a growing interest in reducing the emissions of this gas. Methane biofiltration (MBF) is a cost effective technology for reducing low volume point source emissions of methane. In this technique, microbial oxidation of methane is carried out by methane-oxidizing bacteria (methanotrophs) which use methane as carbon and energy source. MBF uses a granular medium, such as soil or compost, to support the growth of methanotrophic bacteria responsible for converting methane to carbon dioxide (CO₂) and water (H₂O). Even though the biofiltration technique has been shown to be an efficient, practical and viable technology, the design and operational parameters, as well as the relevant microbial processes have not been investigated in depth. In particular, limited research has been done on the effects of sulphur on methane bio-oxidation. Since bacteria require a variety of nutrients for growth, to improve the performance of methane biofiltration, it is important to establish the input quantities of nutrients to be provided to the biofilter to ensure that nutrients are available to sustain the process. The study described in this paper was conducted with the aim of determining the influence of sulphur on methane elimination in a biofilter. In this study, a set of experimental measurements has been carried out to explore how the conversion of elemental sulphur could affect methane oxidation in terms of methanotrophs growth and system pH. Batch experiments with different concentrations of sulphur were performed while keeping the other parameters i.e. moisture content, methane concentration, oxygen level and also compost at their optimum level. The study revealed the tolerable limit of sulphur without any interference to the methane oxidation as well as the particular sulphur concentration leading to the greatest methane elimination capacity. Due to the sulphur oxidation, pH varies in a transient way which affects the microbial growth behavior. All methanotrophs are incapable of growth at pH values below 5.0 and thus apparently are unable to oxidize methane. Herein, the certain pH for the optimal growth of methanotrophic bacteria is obtained. Finally, monitoring methane concentration over time in the presence of sulphur is also presented for laboratory scale biofilters.

Keywords: global warming, methane biofiltration (MBF), methane oxidation, methanotrophs, pH, sulphur

Procedia PDF Downloads 221