Search results for: weak exogeneity

Authors: Poojan Gharat, Haridas Pal, Sharmistha Dutta Choudhury

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Tuning photophysical properties of guest dyes through host-guest interactions involving macrocyclic hosts are the attractive research areas since past few decades, as these changes can directly be implemented in chemical sensing, molecular recognition, fluorescence imaging and dye laser applications. Excited state intramolecular proton transfer (ESIPT) is an intramolecular prototautomerization process display by some specific dyes. The process is quite amenable to tunability by the presence of different macrocyclic hosts. The present study explores the interesting effect of p-sulfonatocalix[n]arene (SCXn) and cyclodextrin (CD) hosts on the excited-state prototautomeric equilibrium of Chrysazine (CZ), a model antitumour drug. CZ exists exclusively in its normal form (N) in the ground state. However, in the excited state, the excited N* form undergoes ESIPT along with its pre-existing intramolecular hydrogen bonds, giving the excited state prototautomer (T*). Accordingly, CZ shows a single absorption band due to N form, but two emission bands due to N* and T* forms. Facile prototautomerization of CZ is considerably inhibited when the dye gets bound to SCXn hosts. However, in spite of lower binding affinity, the inhibition is more profound with SCX6 host as compared to SCX4 host. For CD-CZ system, while prototautomerization process is hindered by the presence of β-CD, it remains unaffected in the presence of γCD. Reduction in the prototautomerization process of CZ by SCXn and βCD hosts is unusual, because T* form is less dipolar in nature than the N*, hence binding of CZ within relatively hydrophobic hosts cavities should have enhanced the prototautomerization process. At the same time, considering the similar chemical nature of two CD hosts, their effect on prototautomerization process of CZ would have also been similar. The atypical effects on the prototautomerization process of CZ by the studied hosts are suggested to arise due to the partial inclusion or external binding of CZ with the hosts. As a result, there is a strong possibility of intermolecular H-bonding interaction between CZ dye and the functional groups present at the portals of SCXn and βCD hosts. Formation of these intermolecular H-bonds effectively causes the pre-existing intramolecular H-bonding network within CZ molecule to become weak, and this consequently reduces the prototautomerization process for the dye. Our results suggest that rather than the binding affinity between the dye and host, it is the orientation of CZ in the case of SCXn-CZ complexes and the binding stoichiometry in the case of CD-CZ complexes that play the predominant role in influencing the prototautomeric equilibrium of the dye CZ. In the case of SCXn-CZ complexes, the results obtained through experimental findings are well supported by quantum chemical calculations. Similarly for CD-CZ systems, binding stoichiometries obtained through geometry optimization studies on the complexes between CZ and CD hosts correlate nicely with the experimental results. Formation of βCD-CZ complexes with 1:1 stoichiometry while formation of γCD-CZ complexes with 1:1, 1:2 and 2:2 stoichiometries are revealed from geometry optimization studies and these results are in good accordance with the observed effects by the βCD and γCD hosts on the ESIPT process of CZ dye.

Keywords: intermolecular proton transfer, macrocyclic hosts, quantum chemical studies, photophysical studies

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Authors: Heba Kamal Mohamed

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Introduction: Tramadol is a weak -opioid receptor agonist with an analgesic effect because of the inhibition of uptake of norepinephrine and serotonin. Nowadays, tramadol hydrochloride is frequently used as a pain reliever. Tramadol is recommended for the management of acute and chronic pain of moderate to severe intensity associated with a variety of diseases or problems, including osteoarthritis, diabetic neuropathy, neuropathic pain, and even perioperative pain in human patients. In obstetrics and gynecology, tramadol is used extensively to treat postoperative pain. Aim of the study: This study was undertaken to investigate the histological (light and electron microscopic) and immunohistochemical effects of long term tramadol treatment on the ovary of adult rats and the possible recovery after tramadol withdrawal. Design: Experimental study. Materials and methods: Thirty adult female albino rats were used in this study. They were classified into three main groups (10 rats each). Group I served as the control group. Group II, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks. Group III, rats were subcutaneously injected with tramadol 40 mg/kg three times per week for 8 weeks then were kept for another 8 weeks without treatment for recovery. At the end of the experiment rats were sacrificed and bilateral oophorectomy was carried out; the ovaries were processed for histological study (light and electron microscopic) and immunohistochemical reaction for caspase-3 (apoptotic protein). Results: Examination of the ovary of tramadol-treated rats (group II) revealed many atretic ovarian follicles, some follicles showed detachment of the oocyte from surrounding granulosa cells and others showed loss of the oocyte. Many follicles revealed degenerated vacuolated oocytes and vacuolated theca folliculi cells. Granulosa cells appeared shrunken, disrupted and loosely attached with vacuolated cytoplasm and pyknotic nuclei. Some follicles showed separation of granulosa cells from the theca folliculi layer. The ultrastructural study revealed the presence of granulosa cells with electron dense indented nuclei, damaged mitochondria and granular vacuolated cytoplasm. Other cells showed accumulation of large amount of lipid droplets in their cytoplasm. Some follicles revealed rarifaction of the cytoplasm of oocytes and absent zona pellucida. Moreover, apoptotic changes were detected by immunohistochemical staining in the form of increased staining intensity to caspase-3 (apoptotic protein). With Masson's Trichrome stain, there was an increased collagen fibre deposition in the ovarian cortical stroma. The wall of blood vessels appeared thickened. In the withdrawal group (group III), there was a little improvement in the histological and immunohistochemical changes. Conclusion: Tramadol had serious deleterious effects on ovarian structure. Thus, it should be used with caution, especially when a long term treatment is indicated. Withdrawal of tramadol led to a little improvement in the structural impairment of the ovary.

Keywords: tramadol, ovary, withdrawal, rats

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Authors: Motaz Alsolaim

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Nowadays, the challenges of running a start-up can be very complex and are perhaps more difficult than at any other time in the past. Changes in technology, manufacturing innovation, and product development, combined with intense competition and market regulations are factors that have put pressure on classic ways of managing firms, thereby forcing change. As a result, the rate of closure, exit or discontinuation of start-ups and young businesses is very high. Despite the essential role of small firms in an economy, they still tend to face obstacles that exert a negative influence on their performance and rate of survival. In fact, it is not easy to determine with any certainty the reasons why small firms fail. For this reason, failure itself is not clearly defined, and its exact causes are hard to diagnose. In this current study, therefore, the barriers to survival will be covered more broadly, especially personal/entrepreneurial, enterprise and environmental factors with regard to various possible reasons for this failure, in order to determine the best solutions and make appropriate recommendations. Methodology: It could be argued that mixed methods might help to improve entrepreneurship research addressing challenges emphasis in previous studies and to achieve the triangulation. Calls for the combined use of quantitative and qualitative research were also made in the entrepreneurship field since entrepreneurship is a multi-faceted area of research. Therefore, explanatory sequential mixed method was used, using questionnaire online survey for entrepreneurs, followed by semi-structure interview. Collecting over 750 surveys and accepting 296 valid surveys, after that 13 interviews from government official seniors, businessmen successful entrepreneurs, and non-successful entrepreneurs. Findings: The first phase findings ( quantitative) shows the obstacles to survive; starting from the personal/ entrepreneurial factors such as; past work experience, lack of skills and interest, are positive factors, while; gender, age and education level of the owner are negative factors. Internal factors such as lack of marketing research and weak business planning are positive. The environmental factors; in economic perspectives; difficulty to find labors, in socio-cultural perspectives; Social restriction and traditions found to be a negative factors. In other hand, from the political perspective; cost of compliance and insufficient government plans found to be a positive factors for small business failure. From infrastructure perspective; lack of skills labor, high level of bureaucracy and lack of information are positive factors. Conclusion: This paper serves to enrich the understanding of failure factors in MENA region more precisely in SA, by minimizing the probability of failure in small-micro entrepreneurial start-up in SA, in the light of the Saudi government’s Vision 2030 plan.

Keywords: small business barriers, start-up business, entrepreneurship, Saudi Arabia

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Authors: Ignitia Motjolopane

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Small and medium enterprises (SMEs) play an important role in economies by contributing to economic growth and employment. In the fourth industrial revolution, the convergence of technologies and the changing nature of work created pressures on economies globally. Generative artificial intelligence (AI) may support SMEs in exploring, exploiting, and transforming business models to align with their growth aspirations. SMEs' growth aspirations fall into four categories: subsistence, income, growth, and speculative. Subsistence-oriented firms focus on meeting basic financial obligations and show less motivation for business model innovation. SMEs focused on income, growth, and speculation are more likely to pursue business model innovation to support growth strategies. SMEs' strategic goals link to distinct business model innovation paths depending on whether SMEs are starting a new business, pursuing growth, or seeking profitability. Integrating generative artificial intelligence in start-up SME business model innovation enhances value creation, user-oriented innovation, and SMEs' ability to adapt to dynamic changes in the business environment. The existing literature may lack comprehensive frameworks and guidelines for effectively integrating generative AI in start-up reiterative business model innovation paths. This paper examines start-up business model innovation path with generative artificial intelligence. A theoretical approach is used to examine start-up-focused SME reiterative business model innovation path with generative AI. Articulating how generative AI may be used to support SMEs to systematically and cyclically build the business model covering most or all business model components and analyse and test the BM's viability throughout the process. As such, the paper explores generative AI usage in market exploration. Moreover, market exploration poses unique challenges for start-ups compared to established companies due to a lack of extensive customer data, sales history, and market knowledge. Furthermore, the paper examines the use of generative AI in developing and testing viable value propositions and business models. In addition, the paper looks into identifying and selecting partners with generative AI support. Selecting the right partners is crucial for start-ups and may significantly impact success. The paper will examine generative AI usage in choosing the right information technology, funding process, revenue model determination, and stress testing business models. Stress testing business models validate strong and weak points by applying scenarios and evaluating the robustness of individual business model components and the interrelation between components. Thus, the stress testing business model may address these uncertainties, as misalignment between an organisation and its environment has been recognised as the leading cause of company failure. Generative AI may be used to generate business model stress-testing scenarios. The paper is expected to make a theoretical and practical contribution to theory and approaches in crafting a robust business model innovation path with generative artificial intelligence in start-up SMEs.

Keywords: business models, innovation, generative AI, small medium enterprises

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Authors: Christian Bruss, Simona Gamba, Davide Azzolini, Federico Podestà

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In this paper, the authors assess the impact of different political and environmental shocks on the size and on the age and gender composition of asylum-related migration flows to Europe. With this paper, the authors contribute to the literature by looking at the impact of different political and environmental shocks on the gender and age composition of migration flows in addition to the size of these flows. Conflicting theories predict different outcomes concerning the relationship between political and environmental shocks and the migration flows composition. Analyzing the relationship between the causes of migration and the composition of migration flows could yield more insights into the mechanisms behind migration decisions. In addition, this research may contribute to better informing national authorities in charge of receiving these migrant, as women and children/the elderly require different assistance than young men. To be prepared to offer the correct services, the relevant institutions have to be aware of changes in composition based on the shock in question. The authors analyze the effect of different types of shocks on the number, the gender and age composition of first time asylum seekers originating from 154 sending countries. Among the political shocks, the authors consider: violence between combatants, violence against civilians, infringement of political rights and civil liberties, and state terror. Concerning environmental shocks, natural disasters (such as droughts, floods, epidemics, etc.) have been included. The data on asylum seekers applying to any of the 32 Schengen Area countries between 2008 and 2015 is on a monthly basis. Data on asylum applications come from Eurostat, data on shocks are retrieved from various sources: georeferenced conflict data come from the Uppsala Conflict Data Program (UCDP), data on natural disasters from the Centre for Research on the Epidemiology of Disasters (CRED), data on civil liberties and political rights from Freedom House, data on state terror from the Political Terror Scale (PTS), GDP and population data from the World Bank, and georeferenced population data from the Socioeconomic Data and Applications Center (SEDAC). The authors adopt a Difference-in-Differences identification strategy, exploiting the different timing of several kinds of shocks across countries. The highly skewed distribution of the dependent variable is taken into account by using count data models. In particular, a Zero Inflated Negative Binomial model is adopted. Preliminary results show that different shocks - such as armed conflict and epidemics - exert weak immediate effects on asylum-related migration flows and almost non-existent effects on the gender and age composition. However, this result is certainly affected by the fact that no time lags have been introduced so far. Finding the correct time lags depends on a great many variables not limited to distance alone. Therefore, finding the appropriate time lags is still a work in progress. Considering the ongoing refugee crisis, this topic is more important than ever. The authors hope that this research contributes to a less emotionally led debate.

Keywords: age, asylum, Europe, forced migration, gender

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Authors: Narges Bahmanyar, Masoud Ghorbani

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Rabies is caused by several species of the genus Lyssavirus in the Rhabdoviridae family. The disease is deadly encephalitis transmitted from warm-blooded animals to humans, and domestic and wild carnivores play the most crucial role in its transmission. The prevalence of rabies in poor areas of developing salinities is constantly posed as a global threat to public health. According to the World Health Organization, approximately 60,000 people die yearly from rabies. Of these, 60% of deaths are related to the Middle East. Although rabies encephalitis is incurable to date, awareness of the disease and the use of vaccines is the best way to combat the disease. Although effective vaccines are available, there is a high cost involved in vaccine production and management to combat rabies. Increasing the prevalence and discovery of new strains of rabies virus requires the need for safe, effective, and as inexpensive vaccines as possible. One of the approaches considered to achieve the quality and quantity expressed through the manufacture of recombinant types of rabies vaccine. Currently, livestock rabies vaccines are used only in inactivated or live attenuated vaccines, the process of inactivation of which pays attention to considerations. The rabies virus contains a negatively polarized single-stranded RNA genome that encodes the five major structural genes (N, P, M, G, L) from '3 to '5 . Rabies virus glycoprotein G, the major antigen, can produce the virus-neutralizing antibody. N-antigen is another candidate for developing recombinant vaccines. However, because it is within the RNP complex of the virus, the possibility of genetic diversity based on different geographical locations is very high. Glycoprotein G is structurally and antigenically more protected than other genes. Protection at the level of its nucleotide sequence is about 90% and at the amino acid level is 96%. Recombinant vaccines, consisting of a pathogenic subunit, contain fragments of the protein or polysaccharide of the pathogen that have been carefully studied to determine which of these molecules elicits a stronger and more effective immune response. These vaccines minimize the risk of side effects by limiting the immune system's access to the pathogen. Such vaccines are relatively inexpensive, easy to produce, and more stable than vaccines containing viruses or whole bacteria. The problem with these vaccines is that the pathogenic subunits may elicit a weak immune response in the body or may be destroyed before they reach the immune cells, which requires nanoparticles to overcome. Suitable for use as an adjuvant. Among these, biodegradable nanoparticles with functional levels are good candidates as adjuvants for the vaccine. In this study, we intend to use beta-glucan nanoparticles as adjuvants. The surface glycoprotein of the rabies virus (G) is responsible for identifying and binding the virus to the target cell. This glycoprotein is the major protein in the structure of the virus and induces an antibody response in the host. In this study, we intend to use rabies virus surface glycoprotein conjugated with beta-glucan nanoparticles to produce vaccines.

Keywords: rabies, vaccines, beta glucan, nanoprticles, adjuvant, recombinant protein

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Authors: Fang Lian, Zefang Chenli, Laijun Ma, Lei Mao

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Up to now, electrolytic process is a popular way to prepare Mn and MnO2 (EMD) with high purity. However, the conventional preparation process of manganese oxide such as Mn3O4 with high purity from electrolytic manganese metal is characterized by long production-cycle, high-pollution discharge and high energy consumption especially initially from low-grade rhodochrosite, the main resources for exploitation and applications in China. Moreover, Mn3O4 prepared from electrolytic manganese shows large particles, single morphology beyond the control and weak chemical activity. On the other hand, hydrometallurgical method combined with thermal decomposition, hydrothermal synthesis and sol-gel processes has been widely studied because of its high efficiency, low consumption and low cost. But the key problem in direct preparation of manganese oxide series from low-grade rhodochrosite is to remove completely the multiple impurities such as iron, silicon, calcium and magnesium. It is urgent to develop a sustainable approach to high pure manganese oxide series with character of short process, high efficiency, environmentally friendly and economical benefit. In our work, the preparation technique of high pure Mn3O4 directly from low-grade rhodochrosite ore (13.86%) was studied and improved intensively, including the effective leaching process and the short purifying process. Based on the same ion effect, the repeated leaching of rhodochrosite with sulfuric acid is proposed to improve the solubility of Mn2+ and inhibit the dissolution of the impurities Ca2+ and Mg2+. Moreover, the repeated leaching process could make full use of sulfuric acid and lower the cost of the raw material. With the aid of theoretical calculation, Ba(OH)2 was chosen to adjust the pH value of manganese sulfate solution and BaF2 to remove Ca2+ and Mg2+ completely in the process of purifying. Herein, the recovery ratio of manganese and removal ratio of the impurity were evaluated via chemical titration and ICP analysis, respectively. Comparison between conventional preparation technique from electrolytic manganese and a sustainable approach directly from low-grade rhodochrosite have also been done herein. The results demonstrate that the extraction ratio and the recovery ratio of manganese reached 94.3% and 92.7%, respectively. The heavy metal impurities has been decreased to less than 1ppm, and the content of calcium, magnesium and sodium has been decreased to less than 20ppm, which meet standards of high pure reagent for energy and electronic materials. In compare with conventional technique from electrolytic manganese, the power consumption has been reduced to ≤2000 kWh/t(product) in our short-process approach. Moreover, comprehensive recovery rate of manganese increases significantly, and the wastewater generated from our short-process approach contains low content of ammonia/ nitrogen about 500 mg/t(product) and no toxic emissions. Our study contributes to the sustainable application of low-grade manganese ore. Acknowledgements: The authors are grateful to the National Science and Technology Support Program of China (No.2015BAB01B02) for financial support to the work.

Keywords: leaching, high purity, low-grade rhodochrosite, manganese oxide, purifying process, recovery ratio

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Authors: A. Cittadino, P. Gantes, C. Coviella, M. Casset, A. Sanchez Caro

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Three currently active landfills receive the waste from Buenos Aires city and the Great Buenos Aires suburbs. One of the first landfills to receive solid waste from this area was located in Villa Dominico, some 7 km south from Buenos Aires City. With an area of some 750 ha, including riparian habitats, divided into 14 cells, it received solid wastes from June 1979 through February 2004. In December 2010, a biological monitoring program was set up by CEAMSE and Universidad Nacional de Lujan, still operational to date. The aim of the monitoring program is to assess the state of several biological groups within the landfill and to follow their dynamics overtime in order to identify if any, early signs of damage the landfill activities might have over the biota present. Bird and rodent populations, aquatic and terrestrial invertebrates’ populations, cells vegetation coverage, and surrounding areas vegetation coverage and main composition are followed by quarterly samplings. Bird species richness and abundance were estimated by observation over walk transects on each environment. A total of 74 different species of birds were identified. Species richness and diversity were high for both riparian surrounding areas and within the landfill. Several grassland -typical of the 'Pampa'- bird species were found within the landfill, as well as some migratory and endangered bird species. Sherman and Tomahawk traps are set overnight for small mammal sampling. Rodent populations are just above detection limits, and the few specimens captured belong mainly to species common to rural areas, instead of city-dwelling species. The two marsupial species present in the region were captured on occasions. Aquatic macroinvertebrates were sampled on a watercourse upstream and downstream the outlet of the landfill’s wastewater treatment plant and are used to follow water quality using biological indices. Water quality ranged between weak and severe pollution; benthic invertebrates sampled before and after the landfill, show no significant differences in water quality using the IBMWP index. Insect biota from yellow sticky cards and pitfall traps showed over 90 different morphospecies, with Shannon diversity index running from 1.9 to 3.9, strongly affected by the season. An easy-to-perform non-expert demandant method was used to assess vegetation coverage. Two scales of determination are utilized: field observation (1 m resolution), and Google Earth images (that allow for a better than 5 m resolution). Over the eight year period of the study, vegetation coverage over the landfill cells run from a low 83% to 100% on different cells, with an average between 95 to 99% for the entire landfill depending on seasonality. Surrounding area vegetation showed almost 100% coverage during the entire period, with an average density from 2 to 6 species per sq meter and no signs of leachate damaged vegetation.

Keywords: biological indicators, biota monitoring, landfill species diversity, waste management

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Authors: Karimova Sitora Yuldashevna

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The August 2021 resurgence of Taliban as a ruling force in Afghanistan once again challenged the global community into dealing with an unprecedentedly unlike-minded government. To express their disapproval of the new regime, Western governments and intergovernmental institutions have suspended their infrastructural projects and other forms of support. Moreover, the Afghan offshore reserves were frozen, and Afghanistan was disconnected from the international financial system, which impeded even independent aid agencies’ work. The already poor provision of aid was then further complicated with political conditionality. The purpose of this paper is to investigate the efficacy of conditional aid policy in the Afghan peacebuilding under Taliban rule and provide recommendations to international donors on further course of action. Arguing that conditionality of aid is a counterproductive factor in the peacebuilding process, this paper employs scholarly literature on peacebuilding alongside reports from International non-governmental organizations INGOs who operate directly in Afghanistan. The existing debate on peacebuilding in Afghanistan revolves around aid as a means of building democratic foundation for achieving peace on communal and national levels and why the previous attempts to do so were unsuccessful. This paper focuses on how to recalibrate the approach to aid provision and peacebuilding in the new reality. In the early 2000s, amid the weak Post-Cold War international will for a profound engagement in the conflict, humanitarian and development aid became the new means of achieving peace. Aid agencies provided resources directly to communities, minimizing the risk of local disputes. Through subsidizing education, governance reforms, and infrastructural projects, international aid accelerated school enrollment, introduced peace education, funded provincial council and parliamentary elections, and helped rebuild a conflict-torn country.When the Taliban seized power, the international community called on them to build an inclusive government based on respect for human rights, particularly girls’ and women’s schooling and work, as a condition to retain the aid flow. As the Taliban clearly failed to meet the demands, development aid was withdrawn. Some key United Nation agencies also refrained from collaborating with the de-facto authorities. However, contrary to the intended change in Talibs’ behavior, such a move has only led to further deprivation of those whom the donors strived to protect. This is because concern for civilians has always been the second priority for the warring parties. This paper consists of four parts. First, it describes the scope of the humanitarian crisis that began in Afghanistan in 2001. Second, it examines the previous peacebuilding attempts undertaken by the international community and the contribution that the international aid had in the peacebuilding process. Third, the paper describes the current regime and its relationships with the international donors. Finally, the paper concludes with recommendations for donors who would have to be more realistic and reconsider their priorities. While it is certainly not suggested that the Taliban regime is legitimized internationally, the crisis calls upon donors to be more flexible in collaborating with the de-facto authorities for the sake of the civilians.

Keywords: Afghanistan, international aid, donors, peacebuilding

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Authors: Sumedha Weerasekara, Morgan Miles, Mark Morrison, Branka Krivokapic-Skoko

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This paper is aimed at exploring the interrelationships among entrepreneurial ecosystem factors and entrepreneurial cognition in regional and metropolitan ecosystems. Entrepreneurial ecosystem factors examined include: culture, infrastructure, access to finance, informal networks, support services, access to universities, and the depth and breadth of the talent pool. Using a multivariate approach we explore the impact of these ecosystem factors or elements on entrepreneurial cognition. In doing so, the existing body of knowledge from the literature on entrepreneurial ecosystem and cognition have been blended to explore the relationship between entrepreneurial ecosystem factors and cognition in a way not hitherto investigated. The concept of the entrepreneurial ecosystem has received increased attention as governments, universities and communities have started to recognize the potential of integrated policies, structures, programs and processes that foster entrepreneurship activities by supporting innovation, productivity and employment growth. The notion of entrepreneurial ecosystems has evolved and grown with the advancement of theoretical research and empirical studies. Importance of incorporating external factors like culture, political environment, and the economic environment within a single framework will enhance the capacity of examining the whole systems functionality to better understand the interaction of the entrepreneurial actors and factors within a single framework. The literature on clusters underplays the role of entrepreneurs and entrepreneurial management in creating and co-creating organizations, markets, and supporting ecosystems. Entrepreneurs are only one actor following a limited set of roles and dependent upon many other factors to thrive. As a consequence, entrepreneurs and relevant authorities should be aware of the other actors and factors with which they engage and rely, and make strategic choices to achieve both self and also collective objectives. The study uses stratified random sampling method to collect survey data from 12 different regions in regional and metropolitan regions of NSW, Australia. A questionnaire was administered online among 512 Small and medium enterprise owners operating their business in selected 12 regions in NSW, Australia. Data were analyzed using descriptive analyzing techniques and partial least squares - structural equation modeling. The findings show that even though there is a significant relationship between each and every entrepreneurial ecosystem factors, there is a weak relationship between most entrepreneurial ecosystem factors and entrepreneurial cognition. In the metropolitan context, the availability of finance and informal networks have the largest impact on entrepreneurial cognition while culture, infrastructure, and support services having the smallest impact and the talent pool and universities having a moderate impact on entrepreneurial cognition. Interestingly, in a regional context, culture, availability of finance, and the talent pool have the highest impact on entrepreneurial cognition, while informal networks having the smallest impact and the remaining factors – infrastructure, universities, and support services have a moderate impact on entrepreneurial cognition. These findings suggest the need for a location-specific strategy for supporting the development of entrepreneurial cognition.

Keywords: academic achievement, colour response card, feedback

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Authors: Aymen Arfaoui, Abdelkader Soumaya, Noureddine Ben Ayed

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The study region is located in the Tunisian Dorsal Backland (Central Mediterranean), which is the easternmost part of the Saharan Atlas mountain range, trending southwest-northeast. Based on our fieldwork, seismic tomography images, seismicity, and previous studies, we propose an interpretation of the relationship between the surface deformation and fault kinematics in the study area and the internal dynamic processes acting in the Central Mediterranean from the Cenozoic to the present. The subduction and dynamics of internal forces beneath the complicated Maghrebides mobile belt have an impact on the Tertiary and Quaternary tectonic regimes in the Pelagian and Atlassic foreland that is part of our study region. The left lateral reactivation of the major "Tunisian N-S Axis fault" and the development of a compressional relay between the Hammamet Korbous and Messella-Ressas faults are possibly a result of tectonic stresses due to the slab roll-back following the Africa/Eurasia convergence. After the slab segmentation and its eastward migration (5–4 Ma) and the formation of the Strait of Sicily "rift zone" further east, a transtensional tectonic regime has been installed in this area. According to seismic tomography images, the STEP fault of the "North-South Axis" at Hammamet-Korbous coincides with the western edge of the "Slab windows" of the Sicilian Channel and the eastern boundary of the positive anomalies attributed to the residual Slab of Tunisia. On the other hand, significant E-W Plio-Quaternary tectonic activity may be observed along the eastern portion of this STEP fault system in the Grombalia zone as a result of recent vertical lithospheric motion in response to the lateral slab migration eastward to Sicily Channel. According to SKS fast splitting directions, the upper mantle flow pattern beneath Tunisian Dorsal is parallel to the NE-SW to E-W orientation of the Shmin identified in the study area, similar to the Plio-Quaternary extensional orientation in the Central Mediterranean. Additionally, the removal of the lithosphere and the subsequent uplift of the sub-lithospheric mantle beneath the topographic highs of the Dorsal and its surroundings may be the cause of the dominant extensional to transtensional Quaternary regime. The occurrence of strike-slip and extensional seismic events in the Pelagian block reveals that the regional transtensional tectonic regime persists today. Finally, we believe that the geodynamic history of the study area since the Cenozoic is primarily influenced by the preexisting weak zones, the African slab detachment, and the upper mantle flow pattern in the central Mediterranean.

Keywords: Tunisia, lithospheric discontinuity (STEP fault), geodynamic evolution, Tunisian dorsal backland, strike-slip fault, seismic tomography, seismicity, central Mediterranean

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Authors: Probuddha Mukhopadhyay

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The infiltration of key elements to the civil structure is foraying its way to reclaim, what is its own. The reclamation of lives and spaces, once challenged, becomes a consistent process of ingress, disguised as parallels to the moving city, disperses into discourses often unheard of and conveniently forgotten. In this age of 'hyper'-urbanization, there are solutions suggested to a plethora of issues faced by citizens, in improving their standards of living. Problems are ancillary to proposals that emerge out of the underlying disorders of the townscape. These interventions result in the formulation of urban policies, to consolidate and optimize, to regularize and to streamline resources. Policy and practice are processes where the politics in policies define the way in which urban solutions are prescribed. Social constraints, that formulate the various cycles of order and disorders within the urban realm, are the stigmas for such interventions. There is often a direct relation of policy to place, no matter how people-centric it may seem to be projected. How we live our lives depends on where we live our lives - a relative statement for urban problems, varies from city to city. Communal compositions, welfare, crisis, socio-economic balance, need for management are the generic roots for urban policy formulation. However, in reality, the gentry administering its environmentalism is the criterion, that shapes and defines the values and expanse of such policies. In relation to the psycho-spatial characteristic of urban spheres with respect to the other side of this game, there have been instances, where the associational values have been reshaped by interests. The public domain reclaimed for exclusivity, thus creating fortified neighborhoods. Here, the citizen cumulative is often drifted by proposals that would over time deplete such landscapes of the city. It is the organized rebellion that in turn formulates further inward looking enclaves of latent aggression. In recent times, it has been observed that the unbalanced division of power and the implied processes of regulating the weak, stem the rebellion who respond in kits and parts. This is a phenomenon that mimics the guerilla warfare tactics, in order to have systems straightened out, either by manipulations or by force. This is the form of the city determined by the various forms insinuated by the state of city wide decisions. This study is an attempt at understanding the way in which development is interpreted by the state and the civil society and the role that community driven processes undertake to reinstate their claims to the city. This is a charter of consolidated patterns of negotiations that tend to counter policies. The research encompasses a study of various contested settlements in two cities of India- Mumbai and Kolkata, tackling dissent through spatial order. The study has been carried out to identify systems - formal and informal, catering to the most challenged interests of the people with respect to their habitat, a model to counter the top-down authoritative framework challenging the legitimacy of such settlements.

Keywords: urban design, insurgence, tactical urbanism, urban governance, civil society, state

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Authors: Shubhangi Roy

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Relational Contracts (informal understandings not enforceable by law) are a common feature of most economies. However, their dominance is higher in developing countries. Such informality of economic sectors is often co-related to lower economic growth. The aim of this paper is to investigate whether informal arrangements i.e. relational contracts are a cause or symptom of lower levels of economic and/or institutional development. The methodology followed involves an initial survey of 150 test subjects in Northern India. The subjects are all members of occupations where they frequently transact ensuring uniformity in transaction volume. However, the subjects are from varied socio-economic backgrounds to ensure sufficient variance in transaction values allowing us to understand the relationship between the amount of money involved to the method of transaction used, if any. Questions asked are quantitative and qualitative with an aim to observe both the behavior and motivation behind such behavior. An overarching similarity observed during the survey across all subjects’ responses is that in an economy like India with pervasive corruption and delayed litigation, economy participants have created alternative social sanctions to deal with non-performers. In a society that functions predominantly on caste, class and gender classifications, these sanctions could, in fact, be more cumbersome for a potential rule-breaker than the legal ramifications. It, therefore, is a symptom of weak formal regulatory enforcement and dispute settlement mechanism. Additionally, the study bifurcates such informal arrangements into two separate systems - a) when it exists in addition to and augments a legal framework creating an efficient socio-legal equilibrium or; b) in conflict with the legal system in place. This categorization is an important step in regulating informal arrangements. Instead of considering the entire gamut of such arrangements as counter-development, it helps decision-makers understand when to dismantle (latter) and when to pivot around existing informal systems (former). The paper hypothesizes that those social arrangements that support the formal legal frameworks allow for cheaper enforcement of regulations with lower enforcement costs burden on the state mechanism. On the other hand, norms which contradict legal rules will undermine the formal framework. Law infringement, in presence of these norms, will have no impact on the reputation of the business or individual outside of the punishment imposed under the law. It is especially exacerbated in the Indian legal system where enforcement of penalties for non-performance of contracts is low. In such a situation, the social norm will be adhered to more strictly by the individuals rather than the legal norms. This greatly undermines the role of regulations. The paper concludes with recommendations that allow policy-makers and legal systems to encourage the former category of informal arrangements while discouraging norms that undermine legitimate policy objectives. Through this investigation, we will be able to expand our understanding of tools of market development beyond regulations. This will allow academics and policymakers to harness social norms for less disruptive and more lasting growth.

Keywords: distribution of income, emerging economies, relational contracts, sample survey, social norms

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Authors: Sandra Carrillo Hoyos

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Mining activities in South America have significantly grown during the last decades, given the abundance of natural resources, the implemented governmental policies to incentivize foreign investment as well as the boom in international prices for metals and oil between 2002 and 2008. While this context allowed the region to occupy a leading position between the top producers of minerals around the world, it has also meant an increase in socio-environmental conflicts which have generated costs and negative impacts not only for the companies but especially for the governments and local communities.During the latest decade, the mining sector in Peru has faced with the social resistance of a large number of communities, which began organizing actions against the implementation of high investing projects. The dissatisfaction has derived in the prevalence of socio-environmental conflicts associated with mining activities, some of them never solved into an agreement. In order to prevent those socio-environmental conflicts and obtain the social license from local communities, most of the mining companies have developed diverse initiatives within the framework of policies and practices of corporate social responsibility (CSR). This paper has assessed the mining sector’s contribution toward the local development management along the last decade, as part of CSR strategies as well as the policies promoted by the Peruvian State. This assessment found that, in the beginning, these initiatives have been based on a philanthropic approach and were reacting to pressures from local stakeholders to maintain the consent to operate from the surrounding communities as well as to create, as a result, a harmonious atmosphere for operations. Due to the weak State presence, such practices have increased the expectations of communities related to the participation of mining companies in solving structural development problems, especially those related to primary needs, infrastructure, education, health, among others. In other words, this paper was focused on analyze in what extent these initiatives have promoted local empowerment for development planning and integrated management of natural resources from a territorial approach. From this perspective, the analysis demonstrates that, while the design and planning of social investment initiatives have improved due to the sector´s sustainability approach, many companies have developed actions beyond their competence during this process. In some cases, the referenced actions have generated dependency with communities, even though this relationship has not exempted the companies of conflict situations with unfortunate consequences. Furthermore, the social programs developed have not necessarily generated a significant impact in improving the quality of life of affected populations. In fact, it is possible to identify that those regions with high mining resources and investment are facing with a situation of poverty and high dependency on mining production. In spite of the revenues derived from mining industry, local governments have not been able to translate the royalties into sustainable development opportunities. For this reason, the proposed paper suggests some challenges for the mining sector contribution to local development based on the best practices and lessons learnt from a benchmarking for the leading mining companies.

Keywords: corporate social responsibility, local development, mining, socio-environmental conflict

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Authors: Naniek Widayati Priyomarsono

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Introduction: In beginning of Karaton formation, namely, era of Javanese kingdom town had the power region outside castle town (called as Mancanegara), settlement of karaton can function as “the space-between” and “space-defense”, besides it was one of components from governmental structure and karaton power at that time (internal servant/abdi dalem and sentana dalem). Upon the Independence of Indonesia in 1945 “Kingdom-City” converted its political status into part of democratic town managed by statutes based on the classification. The latter affects local culture hierarchy alteration due to the physical development and events. Dynamics of social economy activities in Kampung Karaton surrounded by buildings of Complex of Karaton Kasunanan ini, have impact on the urban system disturbed into the región. Also cultural region image fades away with the weak visual access from existant cultural artefacts. That development lacks of giving appreciation to the established region image providing identity of Karaton Kasunanan particularly and identity of Surakarta city in general. Method used is strategy of grounded theory research (research providing strong base of a theory). Research is focused on actors active and passive relevantly getting involved in change process of Karaton settlement. Data accumulated is “Investigation Focus” oriented on actors affecting that change either internal or external. Investigation results are coupled with field observation data, documentation, literature study, thus it takes accurate findings. Findings: Karaton village has potential products as attraction, possessing human resource support, strong motivation from society still living in that settlement, possessing facilities and means supports, tourism event-supporting facilities, cultural art institution, available fields or development area. Data analyzed: To get the expected result it takes restoration in social cultural development direction, and economy, with ways of: Doing social cultural development strategy, economy, and politics. To-do steps are program socialization of Karaton village as Tourism Village, economical development of local society, regeneration pattern, filtering, and selection of tourism development, integrated planning system development, development with persuasive approach, regulation, market mechanism, social cultural event sector development, political development for region activity sector. Summary: In case the restoration is done by getting society involved as subject of that settlement (active participation in the field), managed and packed interestingly and naturally with tourism-supporting facilities development, village of Karaton Kasunanan Surakarta is ready to receive visit of domestic and foreign tourists.

Keywords: karaton village, finding, restoration, economy, Indonesia

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Authors: Shatakshi Garg

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As the world continues to grapple with the COVID-19 pandemic, India, one of the most populous democratic federal developing nation, continues to report the highest active cases and deaths, as well as struggle to let its health infrastructure not succumb to the exponentially growing requirements of hospital beds, ventilators, oxygen to save thousands of lives daily at risk. In this context, the paper outlines the handling of the COVID-19 pandemic since it first hit India in January 2020 – the policy decisions taken by the Union and the State governments from the larger perspective of its federal structure. The Constitution of India adopted in 1950 enshrined the federal relations between the Union and the State governments by way of the constitutional division of revenue-raising and expenditure responsibilities. By way of the 72nd and 73rd Amendments in the Constitution, powers and functions were devolved further to the third tier, namely the local governments, with the intention of further strengthening the federal structure of the country. However, with time, several constitutional amendments have shifted the scales in favour of the union government. The paper briefly traces some of these major amendments as well as some policy decisions which made the federal relations asymmetrical. As a result, data on key fiscal parameters helps establish how the union government gained upper hand at the expense of weak state governments, reducing the local governments to mere constitutional bodies without adequate funds and fiscal autonomy to carry out the assigned functions. This quasi-federal structure of India with the union government amassing the majority of power in terms of ‘funds, functions and functionaries’ exposed the perils of weakening sub-national governments post COVID-19 pandemic. With a complex quasi-federal structure and a heterogeneous population of over 1.3 billion, the announcement of a sudden nationwide lockdown by the union government was followed by a plight of migrants struggling to reach homes safely in the absence of adequate arrangements for travel and safety-net made by the union government. With limited autonomy enjoyed by the states, they were mostly dictated by the union government on most aspects of handling the pandemic, including protocols for lockdown, re-opening post lockdown, and vaccination drive. The paper suggests that certain policy decisions like demonetization, the introduction of GST, etc., taken by the incumbent government since 2014 when they first came to power, have further weakened the states and local governments, which have amounted to catastrophic losses, both economic and human. The role of the executive, legislature and judiciary are explored to establish how all these three arms of the government have worked simultaneously to further weaken and expose the fault-lines of the federal structure of India, which has lent the nation incapacitated to handle this pandemic. The paper then suggests the urgency of re-looking at the federal structure of the country and undertaking measures that strengthen the sub-national governments and restore the federal spirit as was enshrined in the constitution to avoid mammoth human and economic losses from a pandemic of this sort.

Keywords: COVID-19 pandemic, India, federal structure, economic losses

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Authors: Martina Grdiša, Filip Varga, Nina Jeran, Ante Turudić, Zlatko Šatović

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Dalmatian pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.) is a plant species that occurs naturally in the eastern Mediterranean. It is of immense economic importance as it synthesizes and accumulates the phytochemical compound pyrethrin. Pyrethrin consists of several monoterpene esters (pyrethrin I and II, cinerin I and II and jasmolin I and II), which have insecticidal and repellent activity through their synergistic action. In this study, 15 natural Dalmatian pyrethrum populations were sampled along their natural range in Croatia, Bosnia and Herzegovina and Montenegro to characterize and compare their pyrethrin profiles and to define the bioclimatic factors associated with the accumulation of each pyrethrin compound. Pyrethrins were extracted from the dried flower heads of Dalmatian pyrethrum using ultrasound-assisted extraction and the amount of each compound was quantified using high-performance liquid chromatography coupled to DAD-UV /VIS. The biochemical data were subjected to analysis of variance, correlation analysis and multivariate analysis. Quantitative variability within and among populations was found, with population P15 Vranjske Njive, Podgorica having the significantly highest pyrethrin I content (66.47% of total pyrethrin content), while the highest levels of total pyrethrin were found in P14 Budva (1.27% of dry flower weight; DW), followed by P08 Korčula (1.15% DW). Based on the environmental conditions at the sampling sites of the populations, five bioclimatic groups were distinguished, referred to as A, B, C, D, and E, each with rare chemical profile. The first group (A) consisted of the northern Adriatic population P01 Vrbnik, Krk and the population P06 Sevid - the coastal population of the central Adriatic, and generally differed significantly from the other bioclimatic groups by higher average jasmolin II values (2.13% of total pyrethrin). The second group (B) consisted of two central Adriatic island populations (P02 Telašćica, Dugi otok and P03 Žman, Dugi otok), while the remaining central Adriatic island populations were grouped in bioclimatic group C, which was characterized by the significantly highest average pyrethrin II (48.52% of total pyrethrin) and cinerin II (5.31% DW) content. The South Adriatic inland populations P10 Srđ and P11 Trebinje (Bosnia and Herzegovina), and the populations from Montenegro (P12 Grahovo, P13 Lovćen, P14 Budva and P15 Vranjske Njive, Podgorica) formed bioclimatic group E. This bioclimatic group was characterized by the highest average values for pyrethrin I (53.07 % of total pyrethrin), total pyrethrin content (1.06 % DW) and the ratio of pyrethrin I and II (1.85). Slightly lower values (although not significant) for the latter traits were detected in bioclimatic group D (southern Adriatic island populations P07 Vis, P08 Korčula and P09 Mljet). A weak but significant correlation was found between the levels of some pyrethrin compounds and bioclimatic variables (e.g., BIO03 Isothermality and BIO04 Temperature Seasonality), which explains part of the variability observed in the populations studied. This suggests the interconnection between bioclimatic variables and biochemical profiles either through the selection of adapted genotypes or through the ability of species to alter the expression of biochemical traits in response to environmental changes.

Keywords: biopesticides, biochemical variability, pyrethrin, Tanacetum cinerariifolium

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Authors: Varun Joshi, M. S. Rawat

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The Indian Himalayan Region (IHR) is inherently fragile and susceptible to landslide hazard due to its extremely weak geology, highly rugged topography and heavy monsoonal rainfall. One of the most common hazards in the IHR is landslide, and this event is particularly frequent in Himalayan states of India i.e. Jammu & Kashmir, Himachal Pradesh, Uttarakhand, Sikkim, Manipur and Arunachal Pradesh. Landslides are mostly triggered by extreme rainfall events but the incidence increases during monsoon months (June to September). Natural slopes which are otherwise stable but they get destabilized due to anthropogenic activities like construction of various developmental activities and deforestation. These activities are required to fulfill the developmental needs and upliftment of societal status in the region. Landslides also trigger during major earthquakes and reported most observable and damaging phenomena. Studies indicate that the landslide phenomenon has increased many folds due to developmental activities in Himalayan region. Gradually increasing and devastating consequences of landslides turned into one of the most important hydro-geological hazards in Himalayan states especially in Uttarakhand and Sikkim states of India. The recent most catastrophic rainfall in June 2013 in Uttarakhand lead to colossal loss of life and property. The societal damage due to this incident is still to be recovered even after three years. Sikkim earthquake of September 2011 is witnessed for triggering of large number of coseismic landslides. The rescue and relief team faced huge problem in helping the trapped villagers in remote locations of the state due to road side blockade by landslides. The recent past incidences of landslides in Uttarakhand, as well as Sikkim states, created a new domain of research in terms of understanding the phenomena of landslide and management of disaster in such situation. Every year at many locations landslides trigger which force dwellers to either evacuate their dwelling or lose their life and property. The communication and transportation networks are also severely affected by landslides at several locations. Many times the drinking water supply disturbed and shortage of daily need household items reported during monsoon months. To minimize the severity of landslide in IHR requires in-depth research and developmental planning. For most of the areas in the present study, landslide hazard zonation is done on 1:50,000 scale. The land use planning maps on extensive basis are not available. Therefore, there is a need of large-scale landslide hazard zonation and land use planning maps. If the scientist conduct research on desired aspects and their outcome of research is utilized by the government in developmental planning then the incidents of landslide could be minimized, subsequent impact on society, life and property would be reduced. Along with the scientific research, there is another need of awareness generation in the region for stake holders and local dwellers to combat with the landslide hazard, if triggered in their location.

Keywords: coseismic, Indian Himalayan Region, landslide hazard zonation, Sikkim, societal, Uttarakhand

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Authors: Ifeyinwa Victor-Uadiale, Georgina Pearson, Sophie Witter, D. Reidpath

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Introduction: Smoking, alcohol misuse, unhealthy diet, and physical inactivity are the primary drivers of noncommunicable diseases (NCD), including cardiovascular diseases, cancers, respiratory diseases, and diabetes, worldwide. Collectively, these diseases are the leading cause of all global deaths, most of which are premature, affecting people between 30 and 70 years. Empirical evidence suggests that these risk behaviors can be modified by community-based interventions (CBI). However, there is little insight into the mechanisms and contextual factors of successful community interventions that impact risk behaviours for chronic diseases. This study examined “Under what circumstances, for whom, and how, do community-based interventions modify smoking, alcohol use, unhealthy diet, and physical inactivity among adults”. Adopting the Capability (C), Opportunity (O), Motivation (M), Behavior (B) (COM-B) framework for behaviour change, it sought to: (1) identify the mechanisms through which CBIs could reduce tobacco use and alcohol consumption and increase physical activity and the consumption of healthy diets and (2) examine the contextual factors that trigger the impact of these mechanisms on these risk behaviours among adults. Methods: Pawson’s realist review method was used to examine the literature. Empirical evidence and theoretical understanding were combined to develop a realist program theory that explains how CBIs influence NCD risk behaviours. Documents published between 2002 and 2020 were systematically searched in five electronic databases (CINAHL, Cochrane Library, Medline, ProQuest Central, and PsycINFO). They were included if they reported on community-based interventions aimed at cardiovascular diseases, cancers, respiratory diseases, and diabetes in a global context; and had an outcome targeted at smoking, alcohol, physical activity, and diet. Findings: Twenty-nine scientific documents were retrieved and included in the review. Over half of them (n = 18; 62%) focused on three of the four risk behaviours investigated in this review. The review identified four mechanisms: capability, opportunity, motivation, and social support that are likely to change the dietary and physical activity behaviours in adults given certain contexts. There were weak explanations of how the identified mechanisms could likely change smoking and alcohol consumption habits. In addition, eight contextual factors that may affect how these mechanisms impact physical activity and dietary behaviours were identified: suitability to work and family obligations, risk status awareness, socioeconomic status, literacy level, perceived need, availability and access to resources, culture, and group format. Conclusion: The findings suggest that CBIs are likely to improve the physical activity and dietary habits of adults if the intervention function seeks to educate, incentivize, change the environment, and model the right behaviours. The review applies and advances theory, realist research, and the design and implementation of community-based interventions for NCD prevention.

Keywords: community-based interventions, noncommunicable disease, realist program theory, risk behaviors

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Authors: Lijuan Li

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Nitric oxide (NO) has become a fascinating entity in biological chemistry over the past few years. It is a gaseous lipophilic radical molecule that plays important roles in several physiological and pathophysiological processes in mammals, including activating the immune response, serving as a neurotransmitter, regulating the cardiovascular system, and acting as an endothelium-derived relaxing factor. NO functions in eukaryotes both as a signal molecule at nanomolar concentrations and as a cytotoxic agent at micromolar concentrations. The latter arises from the ability of NO to react readily with a variety of cellular targets leading to thiol S-nitrosation, amino acid N-nitrosation, and nitrosative DNA damage. Nitric oxide can readily bind to metals to give metal-nitrosyl (M-NO) complexes. Some of these species are known to play roles in biological NO storage and transport. These complexes have different biological, photochemical, or spectroscopic properties due to distinctive structural features. These recent discoveries have spawned a great interest in the development of transition metal complexes containing NO, particularly its iron complexes that are central to the role of nitric oxide in the body. Spectroscopic evidence would appear to implicate species of “Fe(NO)2+” type in a variety of processes ranging from polymerization, carcinogenesis, to nitric oxide stores. Our research focuses on isolation and structural studies of non-heme iron nitrosyls that mimic biologically active compounds and can potentially be used for anticancer drug therapy. We have shown that reactions between Fe(NO)2(CO)2 and a series of imidazoles generated new non-heme iron nitrosyls of the form Fe(NO)2(L)2 [L = imidazole, 1-methylimidazole, 4-methylimidazole, benzimidazole, 5,6-dimethylbenzimidazole, and L-histidine] and a tetrameric cluster of [Fe(NO)2(L)]4 (L=Im, 4-MeIm, BzIm, and Me2BzIm), resulted from the interactions of Fe(NO)2 with a series of substituted imidazoles was prepared. Recently, a series of sulfur bridged iron di nitrosyl complexes with the general formula of [Fe(µ-RS)(NO)2]2 (R = n-Pr, t-Bu, 6-methyl-2-pyridyl, and 4,6-dimethyl-2-pyrimidyl), were synthesized by the reaction of Fe(NO)2(CO)2 with thiols or thiolates. Their structures and properties were studied by IR, UV-vis, 1H-NMR, EPR, electrochemistry, X-ray diffraction analysis and DFT calculations. IR spectra of these complexes display one weak and two strong NO stretching frequencies (νNO) in solution, but only two strong νNO in solid. DFT calculations suggest that two spatial isomers of these complexes bear 3 Kcal energy difference in solution. The paramagnetic complexes [Fe2(µ-RS)2(NO)4]-, have also been investigated by EPR spectroscopy. Interestingly, the EPR spectra of complexes exhibit an isotropic signal of g = 1.998 - 2.004 without hyperfine splitting. The observations are consistent with the results of calculations, which reveal that the unpaired electron dominantly delocalize over the two sulfur and two iron atoms. The difference of the g values between the reduced form of iron-sulfur clusters and the typical monomeric di nitrosyl iron complexes is explained, for the first time, by of the difference in unpaired electron distributions between the two types of complexes, which provides the theoretical basis for the use of g value as a spectroscopic tool to differentiate these biologically active complexes.

Keywords: di nitrosyl iron complex, metal nitrosyl, non-heme iron, nitric oxide

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Authors: Aikaterini-Melpomeni Papadopoulou, Kyriaki Apergi, Margarita-Vasiliki Panagopoulou, Olga Malisova

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Introduction: Adequate hydration is a vital factor that enhances concentration, memory, and decision-making abilities throughout the workday. Various factors may affect hydration status in workplace settings, and many variables, such as age, gender and activity level affect hydration needs. Employees frequently overlook their hydration needs amid busy schedules and demanding tasks, leading to dehydration that can negatively affect cognitive function, productivity, and overall well-being In addition, dietary habits, including fluid intake and food choices, can either support or hinder optimal hydration. However, factors that affect hydration balance among workers in Greece have not been adequately studied. Objective: This study aims to evaluate the hydration status of the working population in Greece and investigate the various factors that impact hydration status in workplace settings, considering demographic, dietary, and occupational influences in a Greek sample of employees from diverse working environments Materials & Methods: The study included 212 participants (46.2% women) from the working population in Greece. Water intake from both solid and liquid foods was recorded using a semi-quantified drinking frequency questionnaire the validated Water Balance Questionnaire was used to evaluate hydration status. The calculation of water from solid and liquid foods was based on data from the USDA National Nutrient Database. Water balance was calculated subtracting the total fluid loss from the total fluid intake in the body. Furthermore, the questionnaire including additional questions on drinking habits and work-related factors.volunteers answered questions of different categories such as a) demographic socio-economic b) work style characteristics c) health, d) physical activity, e) food and fluid intake, f) fluid excretion and g) trends on fluid and water intake. Individual and multivariate regression analyses were performed to assess the relationships between demographic, work-related factors, and hydration balance. Results: Analysis showed that demographic factors like gender, age, and BMI, as well as certain work-related factors, had a weak and statistically non-significant effect on hydration balance. However, the use of a bottle or water container during work hours (b = 944.93, p < 0.001) and engaging in intense physical activity outside of work (b = -226.28, p < 0.001) were found to have a significant impact. Additionally, the consumption of beverages other than water (b = -416.14, p = 0.059) could negatively impact hydration balance. On average, the total consumption of the sample is 3410 ml of water daily, with men consuming approximately 440 ml / day more water (3470 ml / day) compared to women (3030 ml / day) with this difference also being statistically significant. Finally, the water balance, defined as the difference between water intake and water excretion, was found to be negative on average for the entire sample. Conclusions: This study is among the first to explore hydration status within the Greek working population. Findings indicate that awareness of adequate hydration and individual actions, such as using a water bottle during work, may influence hydration balance.

Keywords: hydration, working population, water balance, workplace behavior

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Authors: Heba M. Saad Eldien, Ola Abdel-Tawab Hussein, Ahmed Yassein Nassar

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Background: Indomethacin is a non-steroidal anti inflammatory drug. Indomethacin induces an injury to gastrointestinal mucosa in experimental animals and humans and their use is associated with a significant risk of hemorrhage, erosions and perforation of both gastric and intestinal ulcers. The anti-inflammatory action of copper complexes is an important activity of their anti-ulcer effect achieved by their intermediary role as a transport form of copper that allow activation of the several copper-dependent enzymes. Therefore, several copper complexes were synthesized and investigated as promising alternative anti-ulcer therapy. Aim of the work: The purpose of this study was to evaluate a copper chelating complex consisting of egg albumin and copper as one of the copper peptides that can be used as anti-inflammatory agent and effective in ameliorates the hazards of the indomethacin on the histological structure of the fundus of the stomach that could be added to raise the efficacy of the currently used simple and cheap gastric anti-inflammatory drug mucogel. Material &methods: This study was carried out on 40 adult male albino rats,divided equally into 4 groups;Group I(control group) received distilled water,Group II(indomethacin treated group) received (25 mg/kg body weight, oral intubation) once, Group III (mucogel treated group)2 mL/rat once daily, oral incubation, Group IV(copper complex group) 1 mL /rat of 30 gm of copper albumin complex was mixed uniformly with mucogel to 100 mL. Treatment has been started six hour after Induction of Ulcers and continued till the 3rd day. The animals sacrificed and was processed for light, transmission electron microscopy(TEM) and immunostaining for inducible nitric oxide synthase(iNOS). Results: Fundic mucosa of group II, showed exfoliation of epithelial cells lining the gland, discontinuity of surface epithelial cells (ulcer formation), vacuolation and detachment of cells, eosinophilic infiltration and congestion of blood vessels in the lamina propria and submucosa. There was thickening and disarrangement of mucosa, weak positive reaction for PAS and marked increase in the collagen fibers lamina propria and the submucosa of the fundus. TEM revealed degeneration of cheif and parietal cells.Marked increase positive reactive of iNOS in all cells of the fundic gland. Group III showed reconstruction of gastric gland with cystic dilatation and vacuolation, moderate decrease of collagen fibers, reduced the intensity of iNOS while in Group IV healthy mucosa with normal surface lining epithelium and fundic glands, strong positive reaction for PAS, marked decrease of collagen fibers and positive reaction for iNOS. TEM revealed regeneration of cheif and parietal cells. Conclusion: Co treatment of copper-albumin complex seems to be useful for gastric ulcer treatment and ameliorates most of hazards of indomethacin.

Keywords: copper complex, gastric ulcer, indomethacin, rat

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Authors: Muhammad Fayyaz Nazir, Ellen Wayenberg, Shahzadaah Faahed Qureshi

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Introduction: The study is based on the Contextual Interaction Theory (CIT) constructs to explore the role of policy actors in implementing the COVID-19 Disease Prevention and Control (DP&C) Policy. The study analyzes the role of healthcare workers' contextual factors, such as cognition, motives, and resources, and their interactions in implementing Social Distancing (SD). In this way, we test a two actors policy implementation theory, i.e., the CIT in a three-actor context. Methods: Data was collected through document analysis and semi-structured interviews. For a qualitative study design, interviews were conducted with questions on cognition, motives, and resources from the healthcare workers involved in implementing SD in the local context in Multan – Pakistan. The possible interactions resulting from contextual factors of the policy actors – healthcare workers were identified through framework analysis protocol guided by CIT and supported by trustworthiness criterion and data saturation. Results: This inquiry resulted in theory application, addition, and enrichment. The theoretical application in the three actor's contexts illustrates the different levels of motives, cognition, and resources of healthcare workers – senior administrators, managers, and healthcare professionals. The senior administrators working in National Command and Operations Center (NCOC), Provincial Technical Committees (PTCs), and Districts Covid Teams (DCTs) were playing their role with high motivation. They were fully informed about the policy and moderately resourceful. The policy implementors: healthcare managers working on implementing the SD within their respective hospitals were playing their role with high motivation and were fully informed about the policy. However, they lacked the required resources to implement SD. The target medical and allied healthcare professionals were moderately motivated but lack of resources and information. The interaction resulted in cooperation and the need for learning to manage the future healthcare crisis. However, the lack of resources created opposition to the implementation of SD. Objectives of the Study: The study aimed to apply a two actors theory in a multi actors context. We take this as an opportunity to qualitatively test the theory in a novel situation of the Covid-19 pandemic and make way for its quantitative application by designing a survey instrument so that implementation researchers can apply CIT through multivariate analyses or higher-order statistical modeling. Conclusion: Applying two actors' implementation theory in exploring a complex case of healthcare intervention in three actors context is a unique work that has never been done before, up to the best of our knowledge. So, the work will contribute to the policy implementation studies by applying, extending, and enriching an implementation theory in a novel case of the Covi-19 pandemic, ultimately fulfilling the gap in implementation literature. Policy institutions and other low or middle-income countries can learn from this research and improve SD implementation by working on the variables with weak significance levels.

Keywords: COVID-19, disease prevention and control policy, implementation, policy actors, social distancing

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Authors: Jing Zhang, Yvonne Reinwald, Nick Poulson, Alicia El Haj, Chung See, Mike Somekh, Melissa Mather

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Biomedical imaging of native tissue using light offers the potential to obtain excellent structural and functional information in a non-invasive manner with good temporal resolution. Image contrast can be derived from intrinsic absorption, fluorescence, or scatter, or through the use of extrinsic contrast. A major challenge in applying optical microscopy to in vivo tissue imaging is the effects of light attenuation which limits light penetration depth and achievable imaging resolution. Recently Selective Plane Illumination Microscopy (SPIM) has been used to map the 3D distribution of fluorophores dispersed in biological structures. In this approach, a focused sheet of light is used to illuminate the sample from the side to excite fluorophores within the sample of interest. Images are formed based on detection of fluorescence emission orthogonal to the illumination axis. By scanning the sample along the detection axis and acquiring a stack of images, 3D volumes can be obtained. The combination of rapid image acquisition speeds with the low photon dose to samples optical sectioning provides SPIM is an attractive approach for imaging biological samples in 3D. To date all implementations of SPIM rely on the use of fluorescence reporters be that endogenous or exogenous. This approach has the disadvantage that in the case of exogenous probes the specimens are altered from their native stage rendering them unsuitable for in vivo studies and in general fluorescence emission is weak and transient. Here we present for the first time to our knowledge a label-free implementation of SPIM that has downstream applications in the clinical setting. The experimental set up used in this work incorporates both label-free and fluorescent illumination arms in addition to a high specification camera that can be partitioned for simultaneous imaging of both fluorescent emission and scattered light from intrinsic sources of optical contrast in the sample being studied. This work first involved calibration of the imaging system and validation of the label-free method with well characterised fluorescent microbeads embedded in agarose gel. 3D constructs of mammalian cells cultured in agarose gel with varying cell concentrations were then imaged. A time course study to track cell proliferation in the 3D construct was also carried out and finally a native tissue sample was imaged. For each sample multiple images were obtained by scanning the sample along the axis of detection and 3D maps reconstructed. The results obtained validated label-free SPIM as a viable approach for imaging cells in a 3D gel construct and native tissue. This technique has the potential use in a near-patient environment that can provide results quickly and be implemented in an easy to use manner to provide more information with improved spatial resolution and depth penetration than current approaches.

Keywords: bioimaging, optics, selective plane illumination microscopy, tissue imaging

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Authors: Omair Anas

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The Persian Gulf has been in turmoil for a long time since the colonial administration has handed over the role to the small and weak kings and emirs who were assured of protection in return of many economic and security promises to them. The regional order, Saudi Arabia evolved was a rentier regional order secured by an expansion of rentier economy and taking responsibility for much of the expenses of the regional order on behalf of relatively poor countries. The two oil booms helped the Saudi state to expand the 'rentier order' driven stability and bring the countries like Egypt, Jordan, Syria, and Palestine under its tutelage. The disruptive misadventure, however, came with Iran's proclamation of the Islamic Revolution in 1979 which it wanted to be exported to its 'un-Islamic and American puppet' Arab neighbours. For Saudi Arabia, even the challenge presented by the socialist-nationalist Arab dictators like Gamal Abdul Nasser and Hafez Al-Assad was not that much threatening to the Saudi Arabia’s then-defensive realism. In the Arab uprisings, the Gulf monarchies saw a wave of insecurity and Iran found it an opportune time to complete the revolutionary process it could not complete after 1979. An alliance of convenience and ideology between Iran and Islamist groups had the real potential to challenge both Saudi Arabia’s own security and its leadership in the region. The disruptive threat appeared at a time when the Saudi state had already sensed an impending crisis originating from the shifts in the energy markets. Low energy prices, declining global demands, and huge investments in alternative energy resources required Saudi Arabia to rationalize its economy according to changing the global political economy. The domestic Saudi reforms remained gradual until the death of King Abdullah in 2015. What is happening now in the region, the Qatar crisis, the Lebanon crisis and the Saudi-Iranian proxy war in Iraq, Syria, and Yemen has combined three immediate objectives, rationalising Saudi economy and most importantly, the resetting the Saudi royal power for Saudi Arabia’s longest-serving future King Mohammad bin Salman. The Saudi King perhaps has no time to wait and watch the power vacuum appearing because of Iran’s expansionist foreign policy. The Saudis appear to be employing an offensive realism by advancing a pro-active regional policy to counter Iran’s threatening influence amid disappearing Western security from the region. As the Syrian civil war is coming to a compromised end with ceding much ground to Iran-controlled militias, Hezbollah and Al-Hashad, the Saudi state has lost much ground in these years and the threat from Iranian proxies is more than a reality, more clearly in Bahrain, Iraq, Syria, and Yemen. This paper attempts to analyse the changing Saudi behaviour in the region, which, the author understands, is shaped by an offensive-realist approach towards finding a favourable security environment for the Saudi-led regional order, a post-rentier order perhaps.

Keywords: terrorism, Saudi Arabia, Rentier State, gulf crisis

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Authors: Zihan Geng, L. Quentin Dixon

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It has been proposed that early bilingual experience confers a number of advantages in the development of executive control mechanisms. Although the literature provides empirical evidence for bilingual benefits, some studies also reported null or mixed results. To make sense of these contradictory findings, the current review synthesize recent empirical studies investigating bilingual effects on children’s executive function and attention control. The publication time of the studies included in the review ranges from 2010 to 2017. The key searching terms are bilingual, bilingualism, children, executive control, executive function, and attention. The key terms were combined within each of the following databases: ERIC (EBSCO), Education Source, PsycINFO, and Social Science Citation Index. Studies involving both children and adults were also included but the analysis was based on the data generated only by the children group. The initial search yielded 137 distinct articles. Twenty-eight studies from 27 articles with a total of 3367 participants were finally included based on the selection criteria. The selective studies were then coded in terms of (a) the setting (i.e., the country where the data was collected), (b) the participants (i.e., age and languages), (c) sample size (i.e., the number of children in each group), (d) cognitive outcomes measured, (e) data collection instruments (i.e., cognitive tasks and tests), and (f) statistic analysis models (e.g., t-test, ANOVA). The results show that the majority of the studies were undertaken in western countries, mainly in the U.S., Canada, and the UK. A variety of languages such as Arabic, French, Dutch, Welsh, German, Spanish, Korean, and Cantonese were involved. In relation to cognitive outcomes, the studies examined children’s overall planning and problem-solving abilities, inhibition, cognitive complexity, working memory (WM), and sustained and selective attention. The results indicate that though bilingualism is associated with several cognitive benefits, the advantages seem to be weak, at least, for children. Additionally, the nature of the cognitive measures was found to greatly moderate the results. No significant differences are observed between bilinguals and monolinguals in overall planning and problem-solving ability, indicating that there is no bilingual benefit in the cooperation of executive function components at an early age. In terms of inhibition, the mixed results suggest that bilingual children, especially young children, may have better conceptual inhibition measured in conflict tasks, but not better response inhibition measured by delay tasks. Further, bilingual children showed better inhibitory control to bivalent displays, which resembles the process of maintaining two language systems. The null results were obtained for both cognitive complexity and WM, suggesting no bilingual advantage in these two cognitive components. Finally, findings on children’s attention system associate bilingualism with heightened attention control. Together, these findings support the hypothesis of cognitive benefits for bilingual children. Nevertheless, whether these advantages are observable appears to highly depend on the cognitive assessments. Therefore, future research should be more specific about the cognitive outcomes (e.g., the type of inhibition) and should report the validity of the cognitive measures consistently.

Keywords: attention, bilingual advantage, children, executive function

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Authors: Thanduxolo Elford Fana

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Rationale and Purpose: Performance management and development system are central to effective and efficient service delivery, especially in highly labour intensive sectors such as South African public health. Performance management and development systems seek to ensure that good employee performance is rewarded accordingly, while those who underperform are developed so that they can reach their full potential. An effective and efficiently implemented performance management system motivates and improves employee engagement. The purpose of this study is to examine the implementation of the performance management and development system and the challenges that are encountered during its implementation in the Eastern Cape Provincial Department of Health. Methods: A qualitative research approach and a case study design was adopted in this study. The primary data were collected through observations, focus group discussions with employees, a group interview with shop stewards, and in-depth interviews with supervisors and managers, from April 2019 to September 2019. There were 45 study participants. In-depth interviews were held with 10 managers at facility level, which included chief executive officer, chief medical officer, assistant director’s in human resources management, patient admin, operations, finance, and two area manager and two operation managers nursing. A group interview was conducted with five shop stewards and an in-depth interview with one shop steward from the group. Five focus group discussions were conducted with clinical and non-clinical staff. The focus group discussions were supplemented with an in-depth interview with one person from each group in order to counter the group effect. Observations included moderation committee, contracting, and assessment meetings. Findings: The study shows that the performance management and development system was not properly implemented. There was non-compliance to performance management and development system policy guidelines in terms of time lines for contracting, evaluation, payment of incentives to good performers, and management of poor performance. The study revealed that the system is ineffective in raising the performance of employees and unable to assist employees to grow. The performance bonuses were no longer paid to qualifying employees. The study also revealed that lack of capacity and commitment, poor communication, constant policy changes, financial constraints, weak and highly bureaucratic management structures, union interference were challenges that were encountered during the implementation of the performance management and development system. Lastly, employees and supervisors were rating themselves three irrespective of how well or bad they performed. Conclusion: Performance management is regarded as vital to improved performance of the health workforce and healthcare service delivery among populations. Effective implementation of performance management and development system depends on well-capacitated and unbiased management at facility levels. Therefore, there is an urgent need to improve communication, link performance management to rewards, and capacitate staff on performance management and development system, as it is key to improved public health sector outcomes or performance.

Keywords: challenges, implementation, performance management and development system, public hospital

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Authors: M. Golam Rabbi

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Theme of wildlife crime is unique in Bangladesh. In earlier of 2010, wildlife crime was not designated as a crime, unlike other offenses. Forest Department and other enforcement agencies were not in full swing to find out the organized crime scene at that time and recorded few cases along with forest crime. However, after the establishment of Wildlife Crime Control Unitin 2012a, total of 374 offenses have been detected with 566 offenders and 37,039 wildlife and trophies were seized till November 2016. Most offenses seem to be committed outside the forests where the presence of the forest staff is minimal. Total detection percentage of offenses is not known, but offenders are not identified in 60% of detected cases (UDOR). Only 20% cases are decided by the courts even after eight years, conviction rate of the total disposal is 70.65%. Mostly six months imprisonment and BDT 5000 fine seems to be the modal penalty. The monetary value of wildlife crime in the country is approximate $0.72M per year and the maximum value counted for reptiles around $0.45M especially for high-level trafficking of geckos and turtles. The most common seizures of wildlife are birds (mynas, munias, parakeets, lorikeets, water birds, etc.) which have domestic demand for pet. Some other wildlife like turtles, lizards and small mammals are also on the list. Venison and migratory waterbirds often seized which has a large quantity demand for consuming at aristocratic level.Due to porous border and weak enforcement in border region poachers use the way for trafficking of geckos, turtles, and tortoises, snakes, venom, tiger and body parts, spotted deerskin, pangolinetc. Those have very high demand in East Asian countries for so-called medicinal purposes. The recent survey also demonstrates new route for illegal trade and trafficking for instance, after poaching of tiger and deer from the Sundarbans, the largest mangrove track of the planet to Thailand through the Bay of Bengal, sharks fins and ray fish through Chittagong seaport and directly by sea routes to Myanmar and Thailand. However, a good number of records of offense demonstrate the transition route from India to South and South East Asian countries. Star tortoises and Hamilton’s turtles are smuggled in from India which mostly seized at Benapole border of Jessore and Hazrat Shah Jajal International Airport of Dhaka, in very large numbers for transmission to East Asian countries. Most of the cases of wildlife trade routes leading to China, Thailand, Malaysia, and Myanmar. Most surprisingly African ivory was seized in Bangladesh recently, which was meant to be trafficked to the South-East Asia. However; forest department is working to fight against wildlife poaching, illegal trade and trafficking in collaboration with other law enforcement agencies. The department needs a clear mandate and to build technical capabilities for identifying, seizing and holding specimens. The department also needs to step out of the forests and must develop the capacity to surveillance and patrol all sensitive locations across the country.

Keywords: Bangladesh forest department, Sundarban, tiger, wildlife crime, wildlife trafficking

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Authors: Oyvind Nordvik, Peder O. L. Heggdal, Jonas Brannstrom, Flemming Vassbotn, Anne Kari Aarstad, Hans Jorgen Aarstad

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Background: Hearing Loss (HL) is a condition that may affect people in all stages of life, but the prevalence increases with age, mostly because of age-related HL, generally referred to as presbyacusis. As human speech is related to relatively high frequencies, even a limited hearing loss at high frequencies may cause impaired speech intelligibility. Being diagnosed with, treated for and living with a chronic condition such as HL, must for many be a disabling and stressful condition that put ones coping resources to test. Stress is a natural part of life and most people will experience stressful events or periods. Chronic diseases, such as HL, are risk factor for distress in individuals, causing anxiety and lowered mood. How an individual cope with HL may be closely connected to the level of distress he or she is experiencing and to personality, which can be defined as those characteristics of a person that account for consistent patterns of feelings, thinking, and behavior. Thus, as to distress in life, such as illness or disease, available coping strategies may be more important than the challenge itself. The same line of arguments applies to level of experienced health-related quality of life (HRQoL). Aim: The aim of this study was to investigate the relationship between distress, HRQoL, reported hearing loss, personality and coping in patients with HL. Method: 158 adult (aged 18-78 years) patients with HL, referred for hearing aid (HA) fitting at Haukeland University Hospital in western Norway, participated in the study. Both first-time users, as well as patients referred for HA renewals were included. First-time users had been pre-examined by an ENT-specialist. The questionnaires were answered before the actual HA fitting procedure. The pure-tone average (PTA; frequencies 0.5, 1, 2, and 4 kHz) was determined for each ear. The Eysenck personality inventory, neuroticism and lie scales, the Theoretically Originated Measure of the Cognitive Activation Theory of Stress (TOMCATS) measuring active coping, hopelessness and helplessness, as well as distress (General Health Questionnaire (GHQ) - 12 items) and the EORTC Quality of Life Questionnaire general part were answered. In addition, we used a revised and shortened version of the Abbreviated Profile of Hearing Aid Benefit (APHAB) as a measure of patient-reported hearing loss. Results: Significant correlations were determined between APHAB (weak), HRQoL scores (strong), distress scores (strong) on the one side and personality and choice of coping scores on the other side. As measured by stepwise regression analyses, the distress and HRQoL scores were scored secondary to the obtained personality and coping scores. The APHAB scores were as determined by regression analyses scored secondary to PTA (best ear), level of neuroticism and lie score. Conclusion: We found that reported employed coping style, distress/HRQoL and personality are closely connected to each other in this patient group. Patient-reported HL was associated to hearing level and personality. There is need for further investigations on these questions, and how these associations may influence the clinical context.

Keywords: coping, distress, hearing loss, personality

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Authors: Sudip Kumar Sinha, Saptarshi Ghosh

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While there’s a perpetual buzz around zinc oxide (ZnO) superstructures for their unique optical features, the versatile material has been constantly utilized to manifest tailored electronic properties through rendition of distinct morphologies. And yet, the unorthodox approach of implementing the novel 1D nanostructures of ZnO (pristine or doped) for volatile sensing applications has ample scope to accommodate new unconventional morphologies. In the last two decades, solid-state sensors have attracted much curiosity for their relevance in identifying pollutant, toxic and other industrial gases. In particular gas sensors based on metal oxide semiconducting (wide Eg) nanomaterials have recently attracted intensive attention owing to their high sensitivity and fast response and recovery time. These materials when exposed to air, the atmospheric O2 dissociates and get absorb on the surface of the sensors by trapping the outermost shell electrons. Finally a depleted zone on the surface of the sensors is formed, that enhances the potential barrier height at grain boundary . Once a target gas is exposed to the sensor, the chemical interaction between the chemisorbed oxygen and the specific gas liberates the trapped electrons. Therefore altering the amount of adsorbate is a considerable approach to improve the sensitivity of any target gas/vapour molecule. Likewise, this study presents a spontaneous but self catalytic creation of Sn-doped ZnO hexagonal nanoprisms on Si (100) substrates through thermal evaporation-condensation method, and their subsequent deployment for volatile sensing. In particular, the sensors were utilized to detect molecules of ethanol, acetone and ammonia below their permissible exposure limits which returned sensitivities of around 85%, 80% and 50% respectively. The influence of Sn concentration on the growth, microstructural and optical properties of the nanoprisms along with its role in augmenting the sensing parameters has been detailed. The single-crystalline nanostructures have a typical diameter ranging from 300 to 500 nm and a length that extends up to few micrometers. HRTEM images confirmed the hexagonal crystallography for the nanoprisms, while SAED pattern asserted the single crystalline nature. The growth habit is along the low index <0001>directions. It has been seen that the growth mechanism of the as-deposited nanostructures are directly influenced by varying supersaturation ratio, fairly high substrate temperatures, and specified surface defects in certain crystallographic planes, all acting cooperatively decide the final product morphology. Room temperature photoluminescence (PL) spectra of this rod like structures exhibits a weak ultraviolet (UV) emission peak at around 380 nm and a broad green emission peak in the 505 nm regime. An estimate of the sensing parameters against dispensed target molecules highlighted the potential for the nanoprisms as an effective volatile sensing material. The Sn-doped ZnO nanostructures with unique prismatic morphology may find important applications in various chemical sensors as well as other potential nanodevices.

Keywords: gas sensor, HRTEM, photoluminescence, ultraviolet, zinc oxide

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