Search results for: critical temperature

Authors: Monika Simkute-Bukante

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Teachers significantly influence student achievements, personal development, and academic success. Consequently, they are subject to heightened expectations and scrutiny from governments, school administrations, parents, and even students. Increasing responsibilities and pressures impact teachers’ professional well-being, contributing to a global trend of increased teacher turnover and shortages due to stress and heavy workloads. Given the critical role of teachers in educating young people, it is essential to implement strategies to retain them. School administrations are pivotal in creating an environment conducive to optimal performance. However, there remains a gap in understanding how school administration leadership impacts teachers' professional well-being and its potential for improvement. This research aims to define teacher professional well-being, identify its attributes, and explore the factors influencing it, with a particular focus on the role of school administration. Employing the concept analysis method, this study reviews scholarly publications from 2019 to 2024 to articulate the components of teacher professional well-being. The findings highlight key attributes of teacher well-being, including self-efficacy, work engagement, job satisfaction, relationships with colleagues and students, support from administration, work autonomy, school climate, time pressure, workload, resilience, stress, burnout, and turnover intentions. The analysis demonstrates that school administration leadership directly affects these aspects by providing support in challenging situations, empowering teachers, offering recognition, facilitating open communication, and ensuring autonomy at work. In conclusion, the research shows that teachers' professional well-being is heavily dependent on relationships with school administration, colleagues, and students, as well as the overall school climate. It suggests that by enhancing these elements, school leaders can significantly improve teacher professional well-being. Recommendations are made for developing strategies to support these relationships, thereby fostering an environment that enhances teacher retention and effectiveness.

Keywords: concept analysis, teacher professional well-being, school administration leadership, well-being factors

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Authors: Saeid Seddegh, Xiaolin Wang, Alan D. Henderson, Dong Chen, Oliver Oims

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The main objective of this research is to study the heat transfer processes and phase change behaviour of a phase change material (PCM) in shell and tube latent heat thermal energy storage (LHTES) systems. The thermal behaviour in a vertical and horizontal shell-and-tube heat energy storage system using a pure thermal conduction model and a combined conduction-convection heat transfer model is compared in this paper. The model is first validated using published experimental data available in literature and then used to study the temperature variation, solid-liquid interface, phase distribution, total melting and solidification time during melting and solidification processes of PCMs. The simulated results show that the combined convection and conduction model can better describe the energy transfer in PCMs during melting process. In contrast, heat transfer by conduction is more significant during the solidification process since the two models show little difference. Also, it was concluded that during the charging process for the horizontal orientation, convective heat transfer has a strong effect on melting of the upper part of the solid PCM and is less significant during melting of the lower half of the solid PCM. However, in the vertical orientation, convective heat transfer is the same active during the entire charging process. In the solidification process, the thermal behavior does not show any difference between horizontal and vertical systems.

Keywords: latent heat thermal energy storage, phase change material, natural convection, melting, shell and tube heat exchanger, melting, solidification

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Authors: Mohammad Javad Seddighi, Avar Almukhtar

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Sustainable urban planning and design (SUPD) play a critical role in achieving the United Nations Sustainable Development Goals (UN SDGs). While there are many rating systems and standards available to assess the sustainability of the built environment, there is still a lack of a comprehensive framework that can assess the quality of SUPD in a specific context. In this paper, we present a framework for assessing the quality of SUPD in Iranian cities, considering their unique cultural, social, and environmental contexts. The aim of this study is to develop a framework for assessing the quality of SUPD in Iranian cities. To achieve this aim, the following objectives are pursued review and synthesis of relevant literature on SUPD, identification of key indicators and criteria for assessing the quality of SUPD in Iranian cities application of the framework to case studies of Iranian cities and evaluation and refinement of the framework based on the results of the case studies. The framework is developed based on a review and synthesis of relevant literature on SUPD, and the identification of key indicators and criteria for assessing the quality of SUPD in Iranian cities. The framework is then applied to case studies of Iranian cities and the results are evaluated and refined. The data for this study are collected through a review of relevant literature on SUPD, including academic journals, conference proceedings, and books. The case studies of Iranian cities are selected based on their relevance and availability of data. The data are collected through interviews, site visits, and document analysis. This paper presents a framework for assessing the quality of SUPD in Iranian cities. The framework is developed based on a review and synthesis of relevant literature, identification of key indicators and criteria, application to case studies, and evaluation and refinement. The framework provides a comprehensive and context-specific approach to assessing the quality of SUPD in Iranian cities. It can be used by urban planners, designers, and policymakers to improve the sustainability and liveability of Iranian cities, and it can be adapted for use in other contexts.

Keywords: sustainable urban planning and design, framework, quality assessment, Iranian cities, case studies

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Authors: Reza Safdari, Goli Arji, Robab Abdolkhani Maryam zahmatkeshan

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Background and purpose: Cardiovascular diseases are among the most common diseases in all societies. The most important step in minimizing myocardial infarction and its complications is to minimize its risk factors. The amount of medical data is increasingly growing. Medical data mining has a great potential for transforming these data into information. Using data mining techniques to generate predictive models for identifying those at risk for reducing the effects of the disease is very helpful. The present study aimed to collect data related to risk factors of heart infarction from patients’ medical record and developed predicting models using data mining algorithm. Methods: The present work was an analytical study conducted on a database containing 350 records. Data were related to patients admitted to Shahid Rajaei specialized cardiovascular hospital, Iran, in 2011. Data were collected using a four-sectioned data collection form. Data analysis was performed using SPSS and Clementine version 12. Seven predictive algorithms and one algorithm-based model for predicting association rules were applied to the data. Accuracy, precision, sensitivity, specificity, as well as positive and negative predictive values were determined and the final model was obtained. Results: five parameters, including hypertension, DLP, tobacco smoking, diabetes, and A+ blood group, were the most critical risk factors of myocardial infarction. Among the models, the neural network model was found to have the highest sensitivity, indicating its ability to successfully diagnose the disease. Conclusion: Risk prediction models have great potentials in facilitating the management of a patient with a specific disease. Therefore, health interventions or change in their life style can be conducted based on these models for improving the health conditions of the individuals at risk.

Keywords: decision trees, neural network, myocardial infarction, Data Mining

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Authors: Yu-Jen Shih, Juan-Zhang Lou

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Nitrogenous compounds, such as NH4+/NH3 and NO3-, have become important contaminants in water resources. Excessive concentration of NH3 leads to eutrophication, which poses a threat to aquatic organisms in the environment. Electrochemical oxidation emerged as a promising water treatment technology, offering advantages such as simplicity, small-scale operation, and minimal reliance on additional chemicals. In this study, a nickel-based metal-organic framework (Ni-MOF) was synthesized using 2-amino terephthalic acid (BDC-NH2) and nickel nitrate. The Ni-MOF was further carbonized as derived nickel oxide and nitrogen-carbon composite, Ni/NiOx/NC. The nickel oxide within the 2D porous carbon texture served as active sites for ammonia oxidation. Results of characterization showed that the Ni-MOF was a hexagonal and flaky nanoparticle. With increasing carbonization temperature, the nickel ions in the organic framework re-crystallized as NiO clusters on the surfaces of the 2D carbon. The electrochemical surface area of Ni/NiOx/NC significantly increased as to improve the efficiency of ammonia oxidation. The phase transition of Ni(OH)2⇌NiOOH at around +0.8 V was the primary mediator of electron transfer. Batch electrolysis was conducted under constant current and constant potential modes. The electrolysis parameters included pyrolysis temperatures, pH, current density, initial feed concentration, and electrode potential. The constant current batch experiments indicated that via carbonization at 800 °C, Ni/NiOx/NC(800) was able to decrease the ammonium nitrogen of 50 mg-N/L to below 1 ppm within 4 hours at a current density of 3 mA/cm2 and pH 11 with negligible oxygenated nitrogen formation. The constant potential experiments confirmed that N2 nitrogen selectivity was enhanced up to 90% at +0.8 V.

Keywords: electrochemical oxidation, nickel oxyhydroxide, metal-organic framework, ammonium, nitrate

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Authors: Gertrude Yidanpoa Grumah

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Ghana boasts of a rich linguistic diversity, with around eighty-seven indigenous languages coexisting with English, the official language. Within this multilingual environment, speech communities adopt bilingual code choices as a common practice, as people seamlessly switch between Ghanaian languages and English. Extensive research has delved into this phenomenon from various perspectives, including the role of bilingual code choices in teaching, its implications for language policy, and its significance in multilingual communities. Yet, a noticeable gap in the literature persists, with most studies focusing on codeswitching between English and the major southern Ghanaian languages like Twi, Ga, and Ewe. The intricate dynamics of codeswitching with minority indigenous languages, such as Mampruli spoken in northern Ghana, remain largely unexplored. This thesis embarks on an investigation into Mampruli-English codeswitching, delving into the linguistic practices of educated Mampruli speakers. The data collection methods encompass interviews, recorded radio programs, and ethnographic observation. The analytical framework employed draws upon the Ethnography of Communication, with observation notes and transcribed interviews thoughtfully classified into discernible themes. The research findings suggest that a bilingual's tendency to switch from Mampruli to English is significantly influenced by factors such as the level of education, age, gender, perceptions of language prestige, and religious beliefs. In essence, this study represents a pioneering endeavor, marking the first comprehensive study on codeswitching practices within the Mampruli-English context and making a significant contribution to our understanding of Mampruli linguistics, covering the social language codes reflecting the speech community. In a region where such research has been scarce for the past four decades, this study addresses a critical knowledge gap, shedding light on the intricate dynamics of language use in northern Ghana.

Keywords: codeswitching, English, ethnography of communication, Mampruli, sociolinguistics

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Authors: Priya Patel, Paresh Patel, Mihir Raval

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Silibinin, a flavanone as an antimicrotubular agent used in the treatment of cancer, was encapsulated in nanoparticles (NPs) of poly (lactide-co-glycolide) (PLGA) polymer using the spray-drying technique. The effects of various experimental parameters were optimized by box-behnken experimental design. Production yield, encapsulation efficiency and dissolution study along with characterization by scanning electron microscopy, DSC, FTIR followed by bioavailability study. Particle size and zeta potential were evaluated by using zetatrac particle size analyzer. Experimental design it was evaluated that inlet temperature and polymer concentration influence on the drug release. Feed flow rate impact on particle size. Results showed that spray drying technique yield 149 nm indicate nanosize range. The small size of the nanoparticle resulted in an enhanced cellular entry and greater bioavailability. Entrapment efficiency was found between 89.35% and 98.36%. Zeta potential shows good stability index of nanoparticle formulation. The in vitro release studies indicated the silibinin loaded PLGA nanoparticles provide controlled drug release over a period of 32 h. Pharmacokinetic studies demonstrated that after oral administration of silibinin-loaded PLGA nanoparticles to rats at a dose of 10 mg/kg, relative bioavailability was enhanced about 8.85-fold, compared to silibinin suspension as control hence, this investigation demonstrated the potential of the experimental design in understanding the effect of the formulation variables on the quality of silibinin loaded PLGA nanoparticles. These results describe an effective strategy of silibinin loaded PLGA nanoparticles and might provide a promising approach against the cancer.

Keywords: silibinin, cancer, nanoparticles, PLGA, bioavailability

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Authors: Asibor Godwin, Adeniyi Funsho

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This study was carried out to investigate the impact of biological treated effluent on the physico-chemical properties of receiving waterbodies and also to establish its suitability for other purposes. It focused on the changes of some physic-chemical variables as one move away from the point of discharge downstream of the waterbodies. Water samples were collected from 14 sampling stations made up of the untreated effluent, treated effluent and receiving streams (before and after treated effluent discharge) over a period of 6 months spanning the dry and rainy seasons. Analyses were carried out on the following: temperature, turbidity, pH, conductivity, major anions and cation, dissolved oxygen, percentage oxygen Saturation, biological oxygen demand (BOD), solids (total solids, suspended solids and dissolved solids), nitrates, phosphates, organic matter and flow discharge using standard analytical methods. The relationships between investigated sites with regards to their physico-chemical properties were analyzed using student-t statistics. Also changes in the treated effluent receiving streams after treated effluent outfall was discussed fully. The physico-chemical water quality of the receiving water bodies meets most of the general water requirements for both domestic and industrial uses. The untreated effluent quality was shown to be of biological origin based on the biological oxygen demand, chloride, dissolved oxygen, total solids, pH and organic matter. The treated effluent showed significant improvement over the raw untreated effluent based on most parameters assessed. There was a significant difference (p<0.05) between the physico-chemical quality of untreated effluent and the treated effluent for the most of the investigated physico-chemical quality. The difference between the discharged treated effluent and the unimpacted section of the receiving waterbodies was also significant (p<0.05) for the most of the physico-chemical parameters.

Keywords: eflluent, Opa River, physico-chemical, waterbody

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Authors: Siwach Sripokangkul, Autthapon Muangming

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The Dao Din group is a gathering of students from the Faculty of Law, Khon Kaen University, a leading university in the northeast of Thailand. The Dao Din group has been one of the most prominent student movements in the past four decades since the bloody massacre of the 6th of October 1976. The group of student is a movement who gather to oppose and protest against different capitalist-run projects that have impacted upon the environment since 2009. The students have become heroes in Thai society and receive support from various groups, especially the middle class who regard the students as role models for the youth. Subsequently, the Dao Din group has received numerous awards between 2011-2013. However, the Dao Din group opposed the military coup d’état of 2014 and the subsequent military junta. Under the military dictatorship regime (2014-present), security officials have hunted, insulted, arrested, and jailed members of the group many times amidst silence from most of the from the middle class. Therefore, this article posits the question of why the Dao Din group which was once the hero and hope of Thai society, has become a political victim in only a few years. The study methods used are the analysis of documentaries, news articles, and interviews with representatives of the Dao Din group. The author argues that Thailand’s middle class previously demonstrated a positive perception of the Dao Din group precisely because that group had earlier opposed policies of the elected Yingluck Shinawatra government, which most of the middle class already despised. However, once the Dao Din group began to protest against the anti-Yingluck military government, then the middle class turned to harshly criticize the Dao Din group. So it can be concluded that the Thai middle class tends to put its partisan interests ahead of a civil society group which has been critical of elected as well as military administrations. This has led the middle class to support the demolishing of Thai democracy. Such a Thai middle-class characteristic not only poses a strong bulwark for the perpetuation of military rule but also destroys a civil society group (composed of young people) who should be the future hope of the nation rather than under the Thai society of darkness.

Keywords: Dao Din student activists, the military coup d’état of 2014, Thai politics, human rights violations

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Authors: Agata Zakrzewska, Dominik Kopeć, Adrian Ochtyra

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The growing number of new cameras, sensors, and research methods allow for a broader application of thermal data in remote sensing vegetation studies. The aim of this research was to check whether it is possible to use thermal infrared data with a spectral range (3.6-4.9 μm) obtained during the day and the night to assess the health condition of selected species of deciduous trees in an urban environment. For this purpose, research was carried out in the city center of Warsaw (Poland) in 2020. During the airborne data acquisition, thermal data, laser scanning, and orthophoto map images were collected. Synchronously with airborne data, ground reference data were obtained for 617 studied species (Acer platanoides, Acer pseudoplatanus, Aesculus hippocastanum, Tilia cordata, and Tilia × euchlora) in different health condition states. The results were as follows: (i) healthy trees are cooler than trees in poor condition and dying both in the daytime and nighttime data; (ii) the difference in the canopy temperatures between healthy and dying trees was 1.06oC of mean value on the nighttime data and 3.28oC of mean value on the daytime data; (iii) condition classes significantly differentiate on both daytime and nighttime thermal data, but only on daytime data all condition classes differed statistically significantly from each other. In conclusion, the aerial thermal data can be considered as an alternative to hyperspectral data, a method of assessing the health condition of trees in an urban environment. Especially data obtained during the day, which can differentiate condition classes better than data obtained at night. The method based on thermal infrared and laser scanning data fusion could be a quick and efficient solution for identifying trees in poor health that should be visually checked in the field.

Keywords: middle wave infrared, thermal imagery, tree discoloration, urban trees

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Authors: Aemro Tazeze Terefe, Mengistu K. Aredo, Abule M. Workagegnehu, Wondimagegn M. Tesfaye

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Climate-induced shocks have been shown to reduce agricultural production and cause fluctuation in output in developing countries. When livelihoods depend on rain-fed agriculture, climate-induced shocks translate into consumption shocks. Despite the substantial improvements in household consumption, climate-induced shocks, and other factors adversely affect consumption dynamics at the household level in Ethiopia. Therefore, household consumption dynamics in the context of climate-induced shocks help to guide resilience capacity and establish appropriate interventions and programs. The research employed three-round panel data based on the Ethiopian Socioeconomic Survey with spatial rainfall data to define unique measures of rainfall variability. The linear dynamic panel model results show that the lagged value of consumption, market shocks, and rainfall variability positively affected consumption dynamics. In contrast, production shocks, temperature, and amount of rainfall had a negative relationship. Coping strategies mitigate adverse climate-induced shocks on consumption aftershocks that smooth consumption over time. Support to increase the resilience capacity of households can involve efforts to make existing livelihoods and forms of production or reductions in the vulnerability of households. Therefore, government interventions are mandatory for asset accumulation agendas that support household coping strategies and respond to shocks. In addition, the dynamic linkage between consumption and significant socioeconomic and institutional factors should be taken into account to minimize the effect of climate-induced shocks on consumption dynamics.

Keywords: climate shock, Ethiopia, fixed-effect model, food security

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Authors: Adel A. Ghoneim

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Air conditioning devices are substantially utilized in the summer months, as a result maximum loads in Kuwait take place in these intervals. Peak energy consumption are usually more expensive to satisfy compared to other standard power sources. The primary objective of the current work is to enhance the performance of high concentrated photovoltaic (HCPV) systems in an attempt to minimize peak power usage in Kuwait using HCPV modules. High concentrated PV multi-junction solar cells provide a promising method towards accomplishing lowest pricing per kilowatt-hour. Nevertheless, these cells have various features that should be resolved to be feasible for extensive power production. A single diode equivalent circuit model is formulated to analyze multi-junction solar cells efficiency in Kuwait weather circumstances taking into account the effects of both the temperature and the concentration ratio. The diode shunt resistance that is commonly ignored in the established models is considered in the present numerical model. The current model results are successfully validated versus measurements from published data to within 1.8% accuracy. Present calculations reveal that the single diode model considering the shunt resistance provides accurate and dependable results. The electrical efficiency (η) is observed to increase with concentration to a specific concentration level after which it reduces. Implementing grid systems is noticed to increase with concentration to a certain concentration degree after which it decreases. Employing grid connected HCPV systems results in significant peak load reduction.

Keywords: grid connected, high concentrated photovoltaic systems, peak load, solar cells

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Authors: Gift Chidi-Onwuta, Iwe Nkem Nkechinyere, Chikamadu Christabelle Chinyere

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The teaching of English is a resource-driven activity that requires rich resource-classroom settings for the delivery of effective lessons and the acquisition of interpersonal skills for integration in a target-language environment. However, throughout the world, English is often taught in low-resource classrooms. This paper is aimed to reveal the common problems associated with teaching English in low-resource environments and the prospects for teachers who found themselves in such undefined teaching settings. Self-structured and validated questionnaire in a closed-ended format, open question format and scaling format was administered to teachers across five countries: Nigeria, Cameroun, Iraq, Turkey, and Sudan. The study adopts situational language teaching theory (SLTT), which emphasizes a performance improvement imperative. This study inclines to this model because it maintains that learning must be fun and enjoyable like playing a favorite sport, just as in real life. Since teaching resources make learning engaging, we found this model apt for the current study. The perceptions of teachers about accessibility and functionality of teaching material resources, the nature of teaching outcomes in resource-less environments, their levels of involvement in improvisation and the prospects associated with resource limitations were sourced. Data were analysed using percentages and presented in frequency tables. Results: showed that a greater number of teachers across these nations do not have access to sufficient productive resource materials that can aid effective English language teaching. Teaching outcomes, from the findings, are affected by low material resources; however, results show certain advantages to teaching English with limited resources: flexibility and autonomy with students and creativity and innovation amongst teachers. Results further revealed group work, story, critical thinking strategy, flex, cardboards and flashcards, dictation and dramatization as common teaching strategies, as well as materials adopted by teachers to overcome low resource-related challenges in classrooms.

Keywords: teaching materials, low-resource environments, English language teaching, situational language theory

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Authors: F. Nasser-Abu Alhija

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In many countries, much efforts and resources are devoted to empowering and integrating minorities within the mainstream population. Major ventures in this route are crafted in higher education institutions where different outreach programs and methods such as lenient entry requirements, monitory incentives, learning skills workshops, tutoring and mentoring, are utilized. Although there is some information regarding these programs, their effectiveness still needs to be thoroughly examined. The Ethiopian community In Israel is one of the minority groups that has been targeted by sponsoring foundations and higher education institutions with the aim to ease the access, persistence and success of its young people in higher education and later in the job market. The evaluation study we propose to present focuses on the implementation of a program designed for this purpose. This program offers relevant candidates for study at a prestigious university a variety of generous incentives that include tuitions, livening allowance, tutoring, mentoring, skills and empowerment workshops and cultural meetings. Ten students were selected for the program and they started their studies in different subject areas before three and half years. A longitudinal evaluation has been conducted since the implementation of the program. Data were collected from different sources: participating students, program coordinator, mentors, tutors, program documents and university records. Questionnaires and interviews were used for collecting data on the different components of the program and on participants' perception of their effectiveness. Participants indicate that the lenient entry requirements and the monitory incentives are critical for starting their studies. During the first year, skills and empowering workshops, torturing and mentoring were evaluated as very important for persistence and success in studies. Tutoring was perceived as very important also at the second year but less importance is attributed to mentoring. Mixed results regarding integration in the Israeli culture emerged. The results are discussed with reference to findings from different settings around the world.

Keywords: access to higher education, minority groups, monitory incentives, torturing, mentoring

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Authors: Jiangang Shen

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Olfactory dysfunction is a common symptom companied by anxiety- and depressive-like behaviors in depressive patients. Chronic stress triggers hormone responses and inhibits the proliferation and differentiation of neural stem cells (NSCs) in the hippocampus and subventricular zone (SVZ)-olfactory bulb (OB), contributing to depressive behaviors and olfactory dysfunction. However, the cellular signaling molecules to regulate chronic stress mediated olfactory dysfunction are largely unclear. Adaptor proteins containing the pleckstrin homology domain, phosphotyrosine binding domain, and leucine zipper motif (APPLs) are multifunctional adaptor proteins. Herein, we tested the hypothesis that APPL2 could inhibit hippocampal neurogenesis by affecting glucocorticoid receptor (GR) signaling, subsequently contributing to depressive and anxiety behaviors as well as olfactory dysfunctions. The major discoveries are included: (1) APPL2 Tg mice had enhanced GR phosphorylation under basic conditions but had no different plasma corticosterone (CORT) level and GR phosphorylation under stress stimulation. (2) APPL2 Tg mice had impaired hippocampal neurogenesis and revealed depressive and anxiety behaviors. (3) GR antagonist RU486 reversed the impaired hippocampal neurogenesis in the APPL2 Tg mice. (4) APPL2 Tg mice displayed higher GR activity and less capacity for neurogenesis at the olfactory system with lesser olfactory sensitivity than WT mice. (5) APPL2 negatively regulates olfactory functions by switching fate commitments of NSCs in adult olfactory bulbs via interaction with Notch1 signaling. Furthermore, baicalin, a natural medicinal compound, was found to be a promising agent targeting APPL2/GR signaling and promoting adult neurogenesis in APPL2 Tg mice and chronic corticosterone-induced depression mouse models. Behavioral tests revealed that baicalin had antidepressant and olfactory-improving effects. Taken together, APPL2 is a critical therapeutic target for antidepressant treatment.

Keywords: APPL2, hippocampal neurogenesis, depressive behaviors and olfactory dysfunction, stress

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Authors: Sujing Wang, Song Wang, Jian Zhang, Qiang Xu

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Flaring emissions during abnormal operating conditions such as plant start-ups, shut-downs, and upsets in chemical process industries (CPI) are usually significant. Flare minimization can help to save raw material and energy for CPI plants, and to improve local environmental sustainability. In this paper, a systematic methodology based on plant-wide dynamic simulation is presented for CPI plant flare minimizations under abnormal operating conditions. Since off-specification emission sources are inevitable during abnormal operating conditions, to significantly reduce flaring emission in a CPI plant, they must be either recycled to the upstream process for online reuse, or stored somewhere temporarily for future reprocessing, when the CPI plant manufacturing returns to stable operation. Thus, the off-spec products could be reused instead of being flared. This can be achieved through the identification of viable design and operational strategies during normal and abnormal operations through plant-wide dynamic scheduling, simulation, and optimization. The proposed study includes three stages of simulation works: (i) developing and validating a steady-state model of a CPI plant; (ii) transiting the obtained steady-state plant model to the dynamic modeling environment; and refining and validating the plant dynamic model; and (iii) developing flare minimization strategies for abnormal operating conditions of a CPI plant via a validated plant-wide dynamic model. This cost-effective methodology has two main merits: (i) employing large-scale dynamic modeling and simulations for industrial flare minimization, which involves various unit models for modeling hundreds of CPI plant facilities; (ii) dealing with critical abnormal operating conditions of CPI plants such as plant start-up and shut-down. Two virtual case studies on flare minimizations for start-up operation (over 50% of emission savings) and shut-down operation (over 70% of emission savings) of an ethylene plant have been employed to demonstrate the efficacy of the proposed study.

Keywords: flare minimization, large-scale modeling and simulation, plant shut-down, plant start-up

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Authors: R. Vimal, K. Hari Hara Subramaniyan, C. Aswin, B. Logeshwaran, M. Ramesh

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Due to several environmental concerns, natural fibers have greatly replaced the synthetic fibers as a reinforcing material in polymer matrix composites. Among the natural fibers, jute fibers are the most abundant plant fibers which are manufactured mainly in countries like India. In recent years, modification of plant fibers with range of chemicals to increase various mechanical and thermal properties has been focused greatly. Among that, some of the plant fibers were modified using succinic anhydride. In the present study, Jute fibers have been modified chemically by treatment with succinic anhydride and glutaric anhydride at different concentrations of 5%, 10%, 20%, 30% and 40%. The fiber modification was done under retting condition at various retention times of 3, 6, 12, 24, 36, and 48 hours. The modification of fiber structure in both the cases is confirmed with Infrared Spectroscopy. The degree of modification increases with increase in retention time, but higher retention time has damaged the fiber structure which is common in both the cases. Comparatively, treatment of fibers with glutaric anhydride has shown efficient output than that of succinic anhydride. The unmodified fibers, succinylated fibers and glutarylated fibers at different retention times are reinforced with epoxy matrix at various volume fractions of fiber under room temperature. The composite made using unmodified fiber is used as a standard material. The tensile strength and flexural strength of the composites are analyzed in detail. Among these, the composite made with glutarylated fiber has shown good mechanical properties when compared to those made of succinylated and unmodified fiber.

Keywords: flexural strength, glutarylation, jute fibers, succinylation, tensile strength

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Authors: Davoud Jafari, Paolo Di Marco, Alessandro Franco, Sauro Filippeschi

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This paper summarizes the results of an investigation into the heat pipe heat transfer for solar collector applications. The study aims to show the feasibility of a concentrating solar collector, which is coupled with a heat pipe. Particular emphasis is placed on the capillary and boiling limits in capillary porous structures, with different mesh numbers and wick thicknesses. A mathematical model of a cylindrical heat pipe is applied to study its behaviour when it is exposed to higher heat input at the evaporator. The steady state analytical model includes two-dimensional heat conduction in the HP’s wall, the liquid flow in the wick and vapor hydrodynamics. A sensitivity analysis was conducted by considering different design criteria and working conditions. Different wicks (mesh 50, 100, 150, 200, 250, and, 300), different porosities (0.5, 0.6, 0.7, 0.8, and 0.9) with different wick thicknesses (0.25, 0.5, 1, 1.5, and 2 mm) are analyzed with water as a working fluid. Results show that it is possible to improve heat transfer capability (HTC) of a HP by selecting the appropriate wick thickness, the effective pore radius, and lengths for a given HP configuration, and there exist optimal design criteria (optimal thick, evaporator adiabatic and condenser sections). It is shown that the boiling and wicking limits are connected and occurs in dependence on each other. As different parts of the HP external surface collect different fractions of the total incoming insolation, the analysis of non-uniform heat flux distribution indicates that peak heat flux is not affecting parameter. The parametric investigations are aimed to determine working limits and thermal performance of HP for medium temperature SC application.

Keywords: screened heat pipes, analytical model, boiling and capillary limits, concentrating collector

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Authors: Samuel K. Degife, Kamal K. Pant, Sapna Jain

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The world´s population and industrialization of countries continued to grow in an alarming rate irrespective of the security for food, energy supply, and pure water availability. As a result, the global energy consumption is observed to increase significantly. Fossil energy resources that mainly comprised of crude oil, coal, and natural gas have been used by mankind as the main energy source for almost two centuries. However, sufficient evidences are revealing that the consumption of fossil resource as transportation fuel emits environmental pollutants such as CO2, NOx, and SOx. These resources are dwindling rapidly besides enormous amount of problems associated such as fluctuation of oil price and instability of oil-rich regions. Biomass is a promising renewable energy candidate to replace fossil-based transportation fuel and chemical production. The present study aims at valorization of hexose sugars (glucose and fructose) using zeolite based catalysts in imidazolium based ionic liquid (1-butyl-3-methylimidazolium chloride, [BMIM] Cl) reaction media. The catalytic effect chromium impregnated H-ZSM-5 (Cr/H-ZSM-5) was studied for dehydration of hexose sugars. The wet impregnation method was used to prepare Cr/H-ZSM-5 catalyst. The characterization of the prepared catalyst was performed using techniques such as Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction analysis (XRD), Temperature-programmed desorption of ammonia (NH3-TPD) and BET-surface area analysis. The dehydration product, 5-hydroxymethylfurfural (5-HMF), was analyzed using high-performance liquid chromatography (HPLC). Cr/H-ZSM-5 was effective in dehydrating fructose with 87% conversion and 55% yield 5-HMF at 180 oC for 30 min of reaction time compared with H-ZSM-5 catalyst which yielded only 31% of 5-HMF at identical reaction condition.

Keywords: chromium, hexose, ionic liquid, , zeolite

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Authors: Wan-I Lee, Nelio Mendoza Figueredo

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The impact of COVID-19 has a significant effect on all sectors of society globally. Health information technology (HIT) has become an effective health strategy in this age of distancing. In this regard, Mobile Health (mHealth) plays a critical role in managing patient and provider workflows during the COVID-19 pandemic. Therefore, the users' perception of service quality about mHealth services plays a significant role in shaping confidence and subsequent behaviors regarding the mHealth users' intention of use. This study's objective was to explore levels of user attributes analyzed by a qualitative method of how health practitioners and patients are satisfied or dissatisfied with using mHealth services; and analyzed the users' intention in the context of Taiwan during the COVID-19 pandemic. This research explores the experienced usability of a mHealth services during the Covid-19 pandemic. This study uses qualitative methods that include in-depth and semi-structured interviews that investigate participants' perceptions and experiences and the meanings they attribute to them. The five cases consisted of health practitioners, clinic staff, and patients' experiences using mHealth services. This study encourages participants to discuss issues related to the research question by asking open-ended questions, usually in one-to-one interviews. The findings show the positive and negative attributes of mHealth service quality. Hence, the significant importance of patients' and health practitioners' issues on several dimensions of perceived service quality is system quality, information quality, and interaction quality. A concept map for perceptions regards to emergency uses' intention of mHealth services process is depicted. The findings revealed that users pay more attention to "Medical care", "ease of use" and "utilitarian benefits" and have less importance for "Admissions and Convenience" and "Social influence". To improve mHealth services, the mHealth providers and health practitioners should better manage users' experiences to enhance mHealth services. This research contributes to the understanding of service quality issues in mHealth services during the COVID-19 pandemic.

Keywords: COVID-19, mobile health, service quality, use intention

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Authors: Lucas Kurth de Azambuja, Loise Silveira da Silva, Gean Vitor Salmoria, Darlan Dallacosta, Carlos Rodrigo de Mello Roesler

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This work provides a physicochemical and thermal characterization assessment of three different hyaluronic acid (HA)-based injections used for rejuvenation skin treatments. The three products analyzed are manufactured by the same manufacturer and commercialized for application on different skin levels. According to the manufacturer, all three HA-based injections are crosslinked and have a concentration of 23 mg/mL of HA, and 0.3% of lidocaine. Samples were characterized by Fourier-transformed infrared (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and scanning electron microscope (SEM) techniques. FTIR analysis resulted in a similar spectrum when comparing the different products. DSC analysis demonstrated that the fusion points differ in each product, with a higher fusion temperature observed in specimen A, which is used for subcutaneous applications, when compared with B and C, which are used for the middle dermis and deep dermis, respectively. TGA data demonstrated a considerable mass loss at 100°C, which means that the product has more than 50% of water in its composition. TGA analysis also showed that Specimen A had a lower mass loss at 100°C when compared to Specimen C. A mass loss of around 220°C was observed on all samples, characterizing the presence of hyaluronic acid. SEM images displayed a similar structure on all samples analyzed, with a thicker layer for Specimen A when compared with B and C. This series of analyses demonstrated that, as expected, the physicochemical and thermal properties of the products differ according to their application. Furthermore, to better characterize the crosslinking degree of each product and their mechanical properties, a set of different techniques should be applied in parallel to correlate the results and, thereby, relate injection application with material properties.

Keywords: hyaluronic acid, characterization, soft-tissue fillers, injectable gels

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Authors: Naiara de Almeida Rios

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The environmental education, from Tbilisi, is signaled as an important instrument for conservation and environmental management. However, the social, economic, political and environmental aspects of each place require an environmental management that corresponds to the reality to which they are inserted, as well as environmental education practices. The city of Belém, the capital of the State of Pará, is one of the most important cities in the Amazon Region, and its vast water dimension requires that its watersheds take a careful look at their socio-environmental management. The Estrada Nova Hydrographic Basin is considered as one of the most critical river basins in the city due to flooding, lack of basic sanitation and degradation of water bodies. In this context, environmental education is understood as one of the necessary conditions to reduce environmental degradation. Environmental education presents itself as an instrument of social transformation and conservation of natural resources (especially water resources), where thinking about the sustainability of natural resources is moving towards dialogue on the importance of building an environmental awareness. The commitment that environmental education proposes covers all spheres of society, since the main objective of the same is the transformation of thought and attitudes from the understanding of reality. Therefore, to analyze how the government is managing the basin, as well as the environmental education practices developed in it, is fundamental, so that government can be charged with improvements for the population and for the natural environment. Therefore, the objective of this study is to analyze the influence of environmental education actions developed by local public authorities in the management of the Estrada Nova Hydrographic Basin, Belém/PA. For the accomplishment of this study, some methodological procedures will be used, like documentary analysis, bibliographical survey and fieldwork. If the multivariate statistical method is used to analyze the results obtained in the field. Unfortunately, public policies in the area of ​environmental education in Belém are still moving in short steps, since government interests have had very little dialogue with the socio-environmental problems that affect the Estrada Nova Hydrographic Basin. Both formal and informal environmental education has been poorly developed, hampering the continuous process proposed by water resources management.

Keywords: environmental education, environmental management, hydrographic basin, water resources

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Authors: Irsa Ejaz, Siyang He, Wei Li, Naiyue Hu, Chaochen Tang, Songbo Li, Meng Li, Boubacar Diallo, Guanghui Xie, Kang Yu

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Background: Near-infrared spectroscopy (NIR) is a non-destructive, fast, and low-cost method to measure the grain quality of different cereals. Previously reported NIR model calibrations using the whole grain spectra had moderate accuracy. Improved predictions are achievable by using the spectra of whole grains, when compared with the use of spectra collected from the flour samples. However, the feasibility for determining the critical biochemicals, related to the classifications for food, feed, and fuel products are not adequately investigated. Objectives: To evaluate the feasibility of using NIRS and the influence of four sample types (whole grains, flours, hulled grain flours, and hull-less grain flours) on the prediction of chemical components to improve the grain sorting efficiency for human food, animal feed, and biofuel. Methods: NIR was applied in this study to determine the eight biochemicals in four types of sorghum samples: hulled grain flours, hull-less grain flours, whole grains, and grain flours. A total of 20 hybrids of sorghum grains were selected from the two locations in China. Followed by NIR spectral and wet-chemically measured biochemical data, partial least squares regression (PLSR) was used to construct the prediction models. Results: The results showed that sorghum grain morphology and sample format affected the prediction of biochemicals. Using NIR data of grain flours generally improved the prediction compared with the use of NIR data of whole grains. In addition, using the spectra of whole grains enabled comparable predictions, which are recommended when a non-destructive and rapid analysis is required. Compared with the hulled grain flours, hull-less grain flours allowed for improved predictions for tannin, cellulose, and hemicellulose using NIR data. Conclusion: The established PLSR models could enable food, feed, and fuel producers to efficiently evaluate a large number of samples by predicting the required biochemical components in sorghum grains without destruction.

Keywords: FT-NIR, sorghum grains, biochemical composition, food, feed, fuel, PLSR

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Authors: Theodore Panton

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As cities in the United States experience critical housing shortages, mass timber presents the opportunity to address this crisis in housing supply while taking advantage of the carbon-positive benefits of sustainably forested wood fiber. Mass timber, however, currently has a low level of adoption in residential multifamily structures due to the risk-averse nature of change within the construction financing, Architecture / Engineering / Contracting (AEC) communities, as well as various agency approval challenges. This study demonstrates how mass timber can be used within the cost and feasibility parameters of a typical multistory residential structure and ultimately address the need for dense urban housing. This study will utilize The Garden District, a mixed-use market-rate housing project in Woodinville, Washington, as a case study to illuminate the potential of mass timber in this application. The Garden District is currently in final stages of permit approval and will commence construction in 2023. It will be the tallest dowel-laminated timber (DLT) residential structure in the United States when completed. This case study includes economic, technical, and design reference points to demonstrate the relevance of the use of this system and its ability to deliver “triple bottom line” results. In terms of results, the study establishes scalable and repeatable approaches to project design and delivery of mass timber in multifamily residential uses and includes economic data, technical solutions, and a summary of end-user advantages. This study discusses the third party tested systems for satisfying acoustical requirements within dwelling units, a key to resolving the use of mass timber within multistory residential use. Lastly, the study will also compare the mass timber solution with a comparable cold formed steel (CFS) system with a similar program, which indicates a net carbon savings of over three million tons over the life cycle of the building.

Keywords: DLT, dowell laminated timber, mass timber, market rate multifamily

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Authors: Chetna Tyagi. G. B. V. S. Lakshmi, Ambuj Tripathi, D. K. Avasthi

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Graphene oxide provides a good host matrix for preparing nanocomposites due to the different functional groups attached to its edges and planes. Being biocompatible, it is used in therapeutic applications. As enzyme-based biosensor requires complicated enzyme purification procedure, high fabrication cost and special storage conditions, we need enzyme-less biosensors for use even in a harsh environment like high temperature, varying pH, etc. In this work, we have prepared both enzyme-based and enzyme-less graphene oxide-based biosensors for glucose detection using glucose-oxidase as enzyme and gold nanoparticles, respectively. These samples were characterized using X-ray diffraction, UV-visible spectroscopy, scanning electron microscopy, and transmission electron microscopy to confirm the successful synthesis of the working electrodes. Electrochemical measurements were performed for both the working electrodes using a 3-electrode electrochemical cell. Cyclic voltammetry curves showed the homogeneous transfer of electron on the electrodes in the scan range between -0.2V to 0.6V. The sensing measurements were performed using differential pulse voltammetry for the glucose concentration varying from 0.01 mM to 20 mM, and sensing was improved towards glucose in the presence of gold nanoparticles. Gold nanoparticles in graphene oxide nanocomposite played an important role in sensing glucose in the absence of enzyme, glucose oxidase, as evident from these measurements. The selectivity was tested by measuring the current response of the working electrode towards glucose in the presence of the other common interfering agents like cholesterol, ascorbic acid, citric acid, and urea. The enzyme-less working electrode also showed storage stability for up to 15 weeks, making it a suitable glucose biosensor.

Keywords: electrochemical, enzyme-less, glucose, gold nanoparticles, graphene oxide, nanocomposite

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Authors: Jogbinder Singh Soodan, Ashok Kumar, Gobind Singh

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Background: This study aims to describe the motor nerve conduction velocity of selected nerves of both the upper and lower extremities in athletes. Thirty high-level sprinters (100 mts and 200 mts) and thirty high level distance runners (3000 mts) were volunteered to participate in the study. Method: Motor nerve conduction velocities (MNCV) of radial and sural nerves were recorded with the help of computerized equipment, NEUROPERFECT (MEDICAID SYSTEMS, India), with standard techniques of supramaximal percutaneus stimulation. The anthropometric measurements taken were body height (cms), age (yrs) and body weight (kgs). The neurophysiological parameters taken were MNCV of radial nerve (upper extremity) and sural nerve (lower extremity) of both sides (i.e. dominant and non-dominant) of the body. The room temperature was maintained at 37 degree Celsius. Results: Significant differences in motor nerve conduction velocities were found between dominant and non-dominant limbs in each group. The MNCV of radial nerve was obtained was significantly higher in the sprinters than long distance runners. The MNCV of sural nerve recorded was significantly higher in sprinters as compared to distance runners. Conclusion: The motor nerve conduction velocity of radial nerve was found to be higher in sprinters as compared to the distance runners and also, the MNCV for sural nerve was found to be higher in sprinters as compared to distance runners. In case of sprinters, the MNCV of radial and sural nerves were higher in dominant limbs (i.e. arms and legs) of both sides of the body. But, in case of distance runners, the MNCV of radial and sural nerves is higher in non dominant limbs.

Keywords: motor nerve conduction velocity, radial nerve, sural nerve, sprinters

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Authors: Weber-Lewerenz Bianca

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Digitization is developing fast and has become a powerful tool for digital planning, construction, and operations. Its transformation bears high potentials for companies, is critical for success, and thus, requires responsible handling. This study provides an assessment of calls made in the sustainable development goals by the United Nations (SDGs), White Papers on AI by international institutions, EU-Commission and German Government requesting for the consideration and protection of values and fundamental rights, the careful demarcation between machine (artificial) and human intelligence and the careful use of such technologies. The study discusses digitization and the impacts of artificial intelligence (AI) in construction engineering from an ethical perspective by generating data via conducting case studies and interviewing experts as part of the qualitative method. This research evaluates critically opportunities and risks revolving around corporate digital responsibility (CDR) in the construction industry. To the author's knowledge, no study has set out to investigate how CDR in construction could be conceptualized, especially in relation to the digitization and AI, to mitigate digital transformation both in large, medium-sized, and small companies. No study addressed the key research question: Where can CDR be allocated, how shall its adequate ethical framework be designed to support digital innovations in order to make full use of the potentials of digitization and AI? Now is the right timing for constructive approaches and apply ethics-by-design in order to develop and implement a safe and efficient AI. This represents the first study in construction engineering applying a holistic, interdisciplinary, inclusive approach to provide guidelines for orientation, examine benefits of AI and define ethical principles as the key driver for success, resources-cost-time efficiency, and sustainability using digital technologies and AI in construction engineering to enhance digital transformation. Innovative corporate organizations starting new business models are more likely to succeed than those dominated by conservative, traditional attitudes.

Keywords: construction engineering, digitization, digital transformation, artificial intelligence, ethics, corporate digital responsibility, digital innovation

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Authors: Stamatis Zoras, Boris Ceranic, Ashley Redfern

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Green House Gas emissions from domestic properties currently account for a substantial part of the total UK’s carbon emissions and is a priority area for UK to reach zero carbon emissions. However, GHG emissions of urban complexes depend on building, road, structural developments etc surfaces that form urban microclimate. This in turn may further influence renewable energy system power generation that depend on solar or wind potential. Moreover, urban climatic conditions are also influenced by the installation of those power generation systems that may impact their own power generation efficiency. Increased air temperature is attributed to densely installed roof based solar panels that consequently impact their own production efficiency. Installation of roof based solar panels requires adequate guidance to enable housing businesses, councils and organisations to implement sufficient measures for improved power generation in relation to local urban microclimate. How microclimate is affected and how, in return, it affects solar power productivity. Derby Council & Derby Homes have been collecting solar panel power generation data for a large number of properties. The different building areas and system operation performance will be studied against microclimate conditions through time. It is envisaged that the outcomes of the study will support a working up strategy for Derby city to ensure that owned homes would be able to access information and data of solar photo voltaic PV and solar thermal panels potential on social housing, helping residents on low incomes create their own green energy to power their homes and heat their homeshot water.

Keywords: microclimate, solar power, urban climatology, urban morphology

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Authors: Nuray Yilmaz Baran, Mehmet Saçak

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Schiff base polymers are one class of conjugated polymers, also called as poly(azomethines). They have drawn the attention of researchers in recent years due to their some properties such as, optoelectronic, semiconductive, and photovoltaic, antimicrobial activities and high thermal stability. In this study, Poly(2-[[4-(dimethylamino)benzylidene]amino] phenol) P(2-DBAP), which is a Schiff base polymer, was synthesized by an oxidative polycondensation reaction of -[[4-(dimethylamino)benzylidene]amino]phenol (2-DBAP) with oxidants NaOCl, H₂O₂ and O₂ in various organic medium. At the end of the polymerizations carried out at various temperatures and time, maximum conversion of the monomer to the polymer could be obtained as around 93.7 %. The structures of the monomer and polymer were characterized by UV-Vis, FTIR and ¹HNMR techniques. Thermal analysis of the polymer was identified by TG-DTG and DTA techniques, and the thermal degradation behavior was supported by Thermo-IR spectra recorded in the temperature range of 25-800 °C. The number average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) of the polymer were found to be 26337, 9860 g/mol 2.67, respectively. The change of electrical conductivity value of the P(2-DBAP) doped with iodine vapor at different temperatures and time was investigated its maximum was measured by increasing 10¹⁰ fold as 2 x10⁻⁴ Scm⁻¹ after doping for 48 h at 60 °C. Antibacterial and antifungal activities of P(2-DBAP) Schiff base and its polymer were also investigated against Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus Faecalis, Klebsiella pneumoniae, Bacillus subtilis, and Candida albicans, Saccharomyces cerevisiae, respectively.

Keywords: conductive properties, polyazomethines, polycondensation reaction, Schiff base polymers, thermal stability

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Authors: Sophie Kroeling, Agnetha Schuchardt

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Striving for sustainability brings a lot of challenges for different fields of interest, e. g. security or health concerns. In Germany, civil protection is predominantly carried out by emergency responders who perform essential tasks of civil protection. Based on theoretical concepts of different psychological stress theories this contribution focuses on the question, how the resilience of emergency responders can be improved. The goal is to identify resources and successful coping strategies that help to prevent and reduce negative outcomes during or after stressful events. The paper will present results from a qualitative analysis of semi-structured qualitative interviews with 20 emergency responders. These results provide insights into the complexity of coping processes (e. g. controlling the situation, downplaying perceived personal threats through humor) and show the diversity of stressors (like complexity of the disastrous situation, intrusive press and media, or lack of social support within the organization). Self-efficacy expectation was a very important resource for coping with stressful situations. The results served as a starting point for a quantitative survey (that was conducted in March 2017), the development of education and training tools for emergency responders and the improvement of critical incident stress management processes. First results from the quantitative study with more than 700 participants show that, e. g., the emergency responders use social coping within their private social network and also within their aid organization and that both are correlated to resilience. Moreover, missing information, bureaucratic problems and social conflicts within the organization are events that the majority of the participants considered very onerous. Further results from regression analysis will be presented. The proposed paper will combine findings from the qualitative study with the quantitative results, illustrating figures and correlations with respective statements from the interviews. At the end, suggestions for the improvement of the emergency responder’s resilience are given and it is discussed how this can make a contribution to strive for civil security and furthermore a sustainable development.

Keywords: civil security, emergency responders, stress, resilience, resources

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