Search results for: African region

Authors: Karthikeyan Kalirajan, Ashok Joshi

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An optimization problem is to setup to maximize the terminal kinetic energy of a maneuverable reentry vehicle (MaRV). The target location, the impact angle is given as constraints. The MaRV uses an explicit guidance law called Vector guidance. This law has two gains which are taken as decision variables. The problem is to find the optimal value of these gains which will result in minimum miss distance and impact angle error. Using a simple 3DOF non-rotating flat earth model and Lockheed martin HP-MARV as the reentry vehicle, the nature of solutions of the optimization problem is studied. This is achieved by carrying out a parametric study for a range of closed loop gain values and the corresponding impact angle error and the miss distance values are generated. The results show that there are well defined lower and upper bounds on the gains that result in near optimal terminal guidance solution. It is found from this study, that there exist common permissible regions (values of gains) where all constraints are met. Moreover, the permissible region lies between flat regions and hence the optimization algorithm has to be chosen carefully. It is also found that, only one of the gain values is independent and that the other dependent gain value is related through a simple straight-line expression. Moreover, to reduce the computational burden of finding the optimal value of two gains, a guidance law called Diveline guidance is discussed, which uses single gain. The derivation of the Diveline guidance law from Vector guidance law is discussed in this paper.

Keywords: Marv guidance, reentry trajectory, trajectory optimization, guidance gain selection

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Authors: Gajanan V. Mane, Rashmi More, Mahesh S. Sonawane, Tushar Lodha, Rohit Sharma

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The diversity of fungi isolated from two different termite species viz., Odontoterms assmuthi and O. abesus was investigated by dilution- plate method, combined with morphological characteristics and sequencing of internal transcribed spacer region. In total, ninety-six fungi were isolated and purified, out of which 69 isolates were obtained from O. assmuthi belonging to 18 genera and 31 species, whereas 27 isolates were obtained from O. abesus belonging to 15 genera and 17 species. The fungal strains were screened for laccase, amylase, cellulase and pectinase enzymes production. Twenty-seven strains were positive for laccase, 59 strains were positive for amylase, 71 strains were positive for cellulase and 72 strains were positive for pectinase enzymes. The antimicrobial activities of the isolated fungi were tested by the dual plate culture method against standard pathogens. Bioactive secondary metabolites were identified by HPLC and LCMS. Four isolates viz., Penicillium goetzii MG 57, Epicoccum sp. MG 39, Penicillium tanzanicum MG 30, Aspergillus polyporicola MG 54, showed positive antimicrobial activity against standard pathogens, Streptococcus pneumonia MCC 2425, Staphylococcus aureus MCC 2408, Pseudomonas aeruginosa MCC 2080, Escherichia coli MCC 2412, Enterococcus faecalis MCC 2409, Klebsiella pneumonia MCC 2451, Micrococcus luteus MCC 2155 and Candida albicans MCC 1151. In conclusion, the study showed that the insect gut harbor fungal diversity, which is futuristic with biotechnological potential and could be a good source of enzymes and antibiotics.

Keywords: termites, fungi, its, enzyme, antimicrobial activity

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Authors: Kenan Morani, Esra Kaya Ayana

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This study aimed to develop a novel pipeline for COVID-19 detection using a large and rigorously annotated database of computed tomography (CT) images. The pipeline consists of UNet-based segmentation, lung extraction, and a classification part, with the addition of optional slice removal techniques following the segmentation part. In this work, a batch normalization was added to the original UNet model to produce lighter and better localization, which is then utilized to build a full pipeline for COVID-19 diagnosis. To evaluate the effectiveness of the proposed pipeline, various segmentation methods were compared in terms of their performance and complexity. The proposed segmentation method with batch normalization outperformed traditional methods and other alternatives, resulting in a higher dice score on a publicly available dataset. Moreover, at the slice level, the proposed pipeline demonstrated high validation accuracy, indicating the efficiency of predicting 2D slices. At the patient level, the full approach exhibited higher validation accuracy and macro F1 score compared to other alternatives, surpassing the baseline. The classification component of the proposed pipeline utilizes a convolutional neural network (CNN) to make final diagnosis decisions. The COV19-CT-DB dataset, which contains a large number of CT scans with various types of slices and rigorously annotated for COVID-19 detection, was utilized for classification. The proposed pipeline outperformed many other alternatives on the dataset.

Keywords: classification, computed tomography, lung extraction, macro F1 score, UNet segmentation

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Authors: Sukhwinder Singh, Julian Park, Dinesh Kumar Benbi

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Although soil health, which is recognized as one of the key determinants of sustainable agricultural development, can be measured by a range of physical, chemical and biological parameters, the widely used parameters include pH, electrical conductivity (EC), organic carbon (OC), plant available phosphorus (P) and potassium (K). Soil health is largely affected by the occurrence of natural events or human activities and can be improved by various land management practices. A database of 120 soil samples collected from farmers’ fields spread across three major agro-climatic zones of Punjab suggested that the average pH, EC, OC, P and K was 8.2 (SD = 0.75, Min = 5.5, Max = 9.1), 0.27 dS/m (SD = 0.17, Min = 0.072 dS/m, Max = 1.22 dS/m), 0.49% (SD = 0.20, Min = 0.06%, Max = 1.2%), 19 mg/kg soil (SD = 22.07, Min = 3 mg/kg soil, Max = 207 mg/kg soil) and 171 mg/kg soil (SD = 47.57, Min = 54 mg/kg soil, Max = 288 mg/kg soil), respectively. Region-wise, pH, EC and K were the highest in south-western district of Ferozpur whereas farmers in north-eastern district of Gurdaspur had the best soils in terms of OC and P. The soils in the central district of Barnala had lower OC, P and K than the respective overall averages while its soils were normal but skewed towards alkalinity. Besides agro-climatic conditions, the size of landholding and farmer education showed a significant association with Soil Fertility Index (SFI), a composite index calculated using the aforementioned parameters’ normalized weightage. All the four stakeholder groups cited the current cropping patterns, burning of rice crop residue, and imbalanced use of chemical fertilizers for change in soil health. However, the current state of soil health in Punjab is unclear, which needs further investigation based on temporal data collected from the same field to see the short and long-term impacts of various crop combinations and varied cropping intensity levels on soil health.

Keywords: soil health, punjab agriculture, sustainability, soil fertility index

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Authors: Khawla Askri, Mohamed Haythem Msaddek, AbdelAziz Sebei

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Climate change combined with the increase in anthropogenic activities will affect coastal groundwater systems around the world and, more particularly, the Cap Bon region in the North East of Tunisia. This study aims to study the impact of climate change and human stress on the salinization and quantification of groundwater in the Wadi Chiba watershed. In this regard, a hydro-climatological study and a hydrogeological study were carried out based on the characterization of the aquifer system of the eastern coast at the level of the watershed of Wadi Chiba in order to seek to identify, first of all, the degradation of the state of the aquifer on the quantitative level by the study of the piezometric and its evolution over time. Secondly, we sought to identify the degradation of the state of the aquifer qualitatively by using the geochemical method, in particular the major elements, to assess the mineralization of the aquifer water and understand its hydrogeochemical functioning. The study of the Na + / Cl- and Ca2 + / Mg2 + chemical relationships confirmed the presence of a marine intrusion downstream of the Wadi Chiba watershed northeast of Cap-Bon accompanied by a piezometric depression. For this purpose, we proceeded to: 1) Mapping of both piezometric data and salinity. 2) The interpretation of the mapping results. 3)Identification of the origin of the localized deterioration in the quality of the aquifer water. Finally, the analysis of the results showed that the scarcity of water is already forcing human actions in the Chiba watershed due to the irrigation of agricultural lands and the overexploitation of the water table in the study area.

Keywords: climate change, human activities, water table, Wadi Chiba watershed, piezometric depression, marine intrusion

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Authors: Tingyu Zhang

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This paper utilizes the Super-SBM model to assess water resources green efficiency (WRGE) among provinces in China and investigate its spatial and temporal features, based on the characteristic framework of “economy-environment-society.” The social network analysis is employed to examine the network pattern and spatial interaction of WRGE. Further, the quadratic assignment procedure method is utilized for examining the influencing factors of the spatial association of WRGE regarding “relationship.” The study reveals that: (1) the spatial distribution of WRGE demonstrates a distribution pattern of Eastern>Western>Central; (2) a remarkable spatial association exists among provinces; however, no strict hierarchical structure is observed. The internal structure of the WRGE network is characterized by the feature of "Eastern strong and Western weak". The block model analysis discovers that the members of the “net spillover” and “two-way spillover” blocks are mostly in the eastern and central provinces; “broker” block, which plays an intermediary role, is mostly in the central provinces; and members of the “net beneficiary” block are mostly in the western region. (3) Differences in economic development, degree of urbanization, water use environment, and water management have significant impacts on the spatial connection of WRGE. This study is dedicated to the realization of regional linkages and synergistic enhancement of WRGE, which provides a meaningful basis for building a harmonious society of human and water coexistence.

Keywords: water resources green efficiency, super-SBM model, social network analysis, quadratic assignment procedure

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Authors: Maria Anjelica P. Ancheta, Roberto S. Soriano, Erickson L. Llaguno

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The main purpose of this study is to examine whether there is a significant relationship between socio-economic class and household water supply demand, through determining or verifying the factors governing water use consumption patterns of households from a sampling from different socio-economic classes in Metro Manila, the national capital region of the Philippines. This study is also an opportunity to augment the lack of local academic literature due to the very few publications on urban household water demand after 1999. In over 600 Metro Manila households, a rapid survey was conducted on their average monthly water consumption and habits on household water usage. The questions in the rapid survey were based on an extensive review of literature on urban household water demand. Sample households were divided into socio-economic classes A-B and C-D. Cluster analysis, dummy coding and outlier tests were done to prepare the data for regression analysis. Subsequently, backward stepwise regression analysis was used in order to determine different statistical models to describe the determinants of water consumption. The key finding of this study is that the socio-economic class of a household in Metro Manila is a significant factor in water consumption. A-B households consume more water in contrast to C-D families based on the mean average water consumption for A-B and C-D households are 36.75 m3 and 18.92 m3, respectively. The most significant proxy factors of socio-economic class that were related to household water consumption were examined in order to suggest improvements in policy formulation and household water demand management.

Keywords: household water uses, socio-economic classes, urban planning, urban water demand management

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Authors: Betty Chiyangwa

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The subject of second-generation migrant youth is under-researched in the context of South Africa. Thus, their opinions and views have been marginalised in social science research. This paper addresses this gap by exploring the complexities of second-generation Mozambican migrant youth’s lived experiences in how they construct their identities and develop a sense of belonging in post-apartheid South Africa, specifically in Bushbuckridge. Bushbuckridge was among the earliest districts to accommodate Mozambican refugees to South Africa in the 1970s and remains associated with large numbers of Mozambicans. Drawing on Crenshaw’s (1989) intersectionality approach, the study contributes to knowledge on South-to-South migration by demonstrating how this approach is operationalised to understand the complex lived experiences of a disadvantaged group in life and possibly in death. In conceptualising the notion of identity among second-generation migrant youth, this paper explores the history and present of first and second-generation Mozambican migrants in South Africa to reveal how being born to migrant parents and raised in a hosting country poses life-long complications in one’s identity and sense of belonging. In the quest to form their identities and construct a sense of belonging, migrant youth employ precariously means to navigate the terrane. This is a case study informed by semi-structured interviews and narrative data gathered from 22 second-generation Mozambican migrant youth between 18 and 34 years who were born to at least one Mozambican parent living in Bushbuckridge and raised in South Africa. Views of two key informants from the South African Department of Home Affairs and the local tribal authority provided additional perspectives on second-generation migrant youth’s lived experiences in Bushbuckridge, which were explored thematically and narratively through Braun and Clarke’s (2012) six-step framework for analysing qualitative data. In exploring the interdependency and interconnectedness of social categories and social systems in Bushbuckridge, the findings revealed that participants’ experiences of identity formation and development of a sense of belonging were marginalised in complex, intersectional and precarious ways where they constantly (re)negotiated their daily experiences, which were largely shaped by their paradoxical migrant status in a host country. This study found that, in the quest for belonging, migrant youths were not a perfectly integrated category but evolved from almost daily lived experiences of creating a living that gave them an identity and a sense of belonging in South Africa. The majority of them shared feelings of living in limbo since childhood and fear of possibly dying in limbo with no clear (solid) sense of belonging to either South Africa or Mozambique. This study concludes that there is a strong association between feelings of identity, sense of belonging and levels of social integration. It recommends the development and adoption of a multilayer comprehensive model for understanding second-generation migrant youth identity and belonging in South Africa which encourages a collaborative effort among individual migrant youth, their family members, neighbours, society, and regional and national institutional structures for migrants to enhance and harness their capabilities and improve their wellbeing in South Africa.

Keywords: bushbuckridge, limbo, mozambican migrants, second-generation

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Authors: Sujan Tyata, Alison Shilpakar, Nayan Bakhadyo, Kushal K. C., Abhas Maskey

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The Koshi River, acknowledged as the "Sorrow of Bihar," poses intricate challenges characterized by recurrent flooding. Within the Koshi Basin, floods have historically inflicted damage on infrastructure, agriculture, and settlements. The Koshi River exhibits a highly braided pattern across a 48 km stretch to the south of Chatara. The devastating flood from the Koshi River, which began in Nepal's Sunsari District in 2008, led to significant casualties and the destruction of agricultural areas.The catastrophe was exacerbated by a levee breach, underscoring the vulnerability of the region's flood defenses. A comprehensive understanding of environmental changes in the area is unveiled through satellite imagery analysis. This analysis facilitates the identification of high-risk zones and their contributing factors. Employing remote sensing, the analysis specifically pinpoints locations vulnerable to levee breaches. Topographical features of the area along with longitudinal and cross sectional profiles of the river and levee obtained from digital elevation model are used in the hydrological analysis for assessment of flood. To mitigate the impact of floods, the strategy involves the establishment of reservoirs upstream. Leveraging satellite data, optimal locations for water storage are identified. This approach presents a dual opportunity to not only alleviate flood risks but also catalyze the implementation of pumped storage hydropower initiatives. This holistic approach addresses environmental challenges while championing sustainable energy solutions.

Keywords: flood mitigation, levee, remote sensing, satellite imagery analysis, sustainable energy solutions

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Authors: G. Cunningham, E. Cantor, X. Wu, F. Shen, G. Jiang, S. Philips, C. Bales, Y. Xiao, T. R. Cummins, J. C. Fehrenbacher, B. P. Schneider

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Background: Taxane-induced peripheral neuropathy (TIPN) is the most devastating survivorship issue for patients receiving therapy. Dose reductions due to TIPN in the curative setting lead to inferior outcomes for African American patients, as prior research has shown that this group is more susceptible to developing severe neuropathy. The mechanistic underpinnings of TIPN, however, have not been entirely elucidated. While it would be appealing to use primary tissue to study the development of TIPN, procuring nerves from patients is not realistically feasible, as nerve biopsies are painful and may result in permanent damage. Therefore, our laboratory has investigated paclitaxel-induced neuronal morphological and molecular changes using an ex vivo model of human-induced pluripotent stem cell (iPSC)-derived neurons. Methods: iPSCs are undifferentiated and endlessly dividing cells that can be generated from a patient’s somatic cells, such as peripheral blood mononuclear cells (PBMCs). We successfully reprogrammed PBMCs into iPSCs using the Erythroid Progenitor Reprograming Kit (STEMCell Technologiesᵀᴹ); pluripotency was verified by flow cytometry analysis. iPSCs were then induced into neurons using a differentiation protocol that bypasses the neural progenitor stage and uses selected small-molecule modulators of key signaling pathways (SMAD, Notch, FGFR1 inhibition, and Wnt activation). Results: Flow cytometry analysis revealed expression of core pluripotency transcription factors Nanog, Oct3/4 and Sox2 in iPSCs overlaps with commercially purchased pluripotent cell line UCSD064i-20-2. Trilineage differentiation of iPSCs was confirmed with immunofluorescent imaging with germ-layer-specific markers; Sox17 and ExoA2 for ectoderm, Nestin, and Pax6 for mesoderm, and Ncam and Brachyury for endoderm. Sensory neuron markers, β-III tubulin, and Peripherin were applied to stain the cells for the maturity of iPSC-derived neurons. Patch-clamp electrophysiology and calcitonin gene-related peptide (CGRP) release data supported the functionality of the induced neurons and provided insight into the timing for which downstream assays could be performed (week 4 post-induction). We have also performed a cell viability assay and fluorescence-activated cell sorting (FACS) using four cell-surface markers (CD184, CD44, CD15, and CD24) to select a neuronal population. At least 70% of the cells were viable in the isolated neuron population. Conclusion: We have found that these iPSC-derived neurons recapitulate mature neuronal phenotypes and demonstrate functionality. Thus, this represents a patient-derived ex vivo neuronal model to investigate the molecular mechanisms of clinical TIPN.

Keywords: chemotherapy, iPSC-derived neurons, peripheral neuropathy, taxane, paclitaxel

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Authors: Mohannad Tarrad

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The research deals with the beginnings of the vernacular Jordanian architecture since the establishment of the Jordanian state in the early nineteenth century until now, where the Jordanian architecture was based on the interactions of the Jordanian society with the surrounding environment, where the local materials available in the construction area were used, and the construction systems inherited from previous civilizations were used. The builders in Jordan relied on exchanging knowledge and transferring it from one generation to another, where they were able to formulate a construction style capable of responding to the requirement of architectural spaces, and each region of Jordan has its own way of building, as there are various geographical areas in Jordan, including agricultural, mountainous and desert areas. Then the research touched on a historical study of the architectural space and identifying the value of the architectural space in the Jordanian social life, which is related to the customs and traditions of a society influenced by the Arab Islamic civilization, and then the construction, the structural structure, its characteristics and the constituent elements of the building were defined in the vernacular l Jordanian architecture. From the structural point of view, and then to identify the structural materials used in the structural structure and the impact of the structural structure on the design from several aspects, leading to the interior space and the factors affecting it. The research aims to explain and clarify the interconnected design and construction solutions in the vernacular Jordanian architecture in a manner that respects the environmental context, taking into account the material cost of the building, where the financial situation of the home owner plays an important role in choosing the building material and construction method. Case studies from heritage buildings from several Jordanian regions will be analyzed to illustrate the idea of the research.

Keywords: construction systems, architectural space, environmental context, Jordanian architecture

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Authors: Yobo Opare-Addo

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Ghana came under a military and democratic rule of the same leadership from 1981-2000. These were the Provisional National Defense Council (PNDC), a military government and a democratic government, the National Democratic Congress (NDC) both under the leadership of Flt. Lt. J.J. Rawlings. Meanwhile the year 1985 marked a turning point in the development of the tourism industry in Ghana. Interest in tourism among African governments and for that matter the ‘PNDC cum NDC Government’ (PNDC/NDC) arose because of adverse developments in intangible exports and a corresponding decline in commodity export earnings. The ‘PNDC/NDC Government’ undertook measures and policies to improve the tourism industry and at the same time embarked on export diversification to reap the foreign exchange that the industry could generate in Ghana. The objective of this paper is to examine the measures and policies of the PNDC/NDC to improve the tourism industry in order to reap the foreign exchange. It specifically interrogates the role of the government as an agent of tourism development, through its deliberate creation of a conducive environment for tourism to flourish, the involvement of the private sector both foreign and local and the provision of tourism facilities and infrastructure and how these factors impacted on the tourism industry in Ghana. In the final analysis it evaluates the degree of success of the PNDC/NDC Government in this arena of Ghana’s socio-cultural and economic development. Introduction The Provisional National Defense Council (PNDC), a military government under the leadership of Flt. Lt J.J. Rawlings overthrew a constitutionally elected government of People’s National Party in 1981. In 1992, the National Democratic Congress (NDC) won the general election conducted in December. Flt. Lt. J.J. Rawlings, the party’s leader became the President of the Fourth Republic from January 1993 to December 2000. It was refreshing to see Ghanaians embrace democracy with renewed energy, zeal, and enthusiasm. This paper takes a critical look at the efforts of the PNDC cum NDC Government (PNDC/NDC) to develop tourism in Ghana during the period from 1981-2000 Methodology: Qualitative method of research was adopted for the study. Data was collected from both primary and secondary sources, and analysis was done using descriptive analysis because descriptive analysis made it possible to describe or summarize the statistical data in the research. To gather data from primary sources, questionnaires, oral interviews, and semi-structured discussions were conducted. Respondents included public officials from Ghana Tourist Board, Ministry of Tourism, Hoteliers, restaurant operators and travel and tour operators in Accra. Secondary data sources included articles in journals, reports, magazines, bulletins, and books. The major findings included statistical data for tourism arrivals and receipts during the period and the status of the industry by the year 2000. Conclusion: The paper contributes to knowledge on political and historical aspects of tourism development in Ghana, which is almost non-existent, attitudes of the PNDC cum NDC government towards tourism development and the debates on the generation of foreign exchange to Ghana and third world countries.

Keywords: ghana, infrastructure, policies, privatization, tourism facilities

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Authors: Amina Farooq, Nauman Zafar Butt

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This paper is about methods and tools for counting particles of interest, such as cells. A microfluidic system with interconnected electronics on a flexible substrate, inlet-outlet ports and interface schemes, sensitive and selective detection of cells specificity, and processing of cell counting at polymer interfaces in a microscale biosensor for use in the detection of target biological and non-biological cells. The development of fluidic channels, planar fluidic contact ports, integrated metal electrodes on a flexible substrate for impedance measurements, and a surface modification plasma treatment as an intermediate bonding layer are all part of the fabrication process. Magnetron DC sputtering is used to deposit a double metal layer (Ti/Pt) over the polypropylene film. Using a photoresist layer, specified and etched zones are established. Small fluid volumes, a reduced detection region, and electrical impedance measurements over a range of frequencies for cell counts improve detection sensitivity and specificity. The procedure involves continuous flow of fluid samples that contain particles of interest through the microfluidic channels, counting all types of particles in a portion of the sample using the electrical differential counter to generate a bipolar pulse for each passing cell—calculating the total number of particles of interest originally in the fluid sample by using MATLAB program and signal processing. It's indeed potential to develop a robust and economical kit for cell counting in whole-blood samples using these methods and similar devices.

Keywords: impedance, biochip, cell counting, microfluidics

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Authors: Traci A. Hefner

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Limited research exists on the readiness of emergency departments to respond to human trafficking (HT). The purpose of this qualitative case study was to improve the readiness of a Department of Emergency Medicine (ED), located in the southeast region of the United States, in identifying, assessing, and responding to trafficked individuals. The research objectives were to 1) provide an organizing framework to understand the ED’s readiness to respond to HT, using the Transtheoretical Model’s stages of change construct, 2) explain the readiness of the ED through a three-pronged contextual approach that included policies and procedures, patient data collection processes, and clinical practice methods, and 3) develop recommendations to respond to HT. Content analysis was used for document reviews and on-site observations, while thematic analysis identified themes of staff perceptions of the ED’s readiness in interviews of over 30 clinical and non-clinical healthcare professionals. Results demonstrated low levels of readiness to identify HT through the ED’s policies and procedures, data collection processes, and clinical practice methods. Clinical practice-related factors consisted of limited awareness of HT warning signs and low-levels of knowledge about community resources for possible HT referrals. Policy and practice recommendations to increase the ED’s readiness to respond to HT included: developing staff trainings across the ED system to enhance awareness of HT warning signs, incorporating HT into current policies and procedures for vulnerable patient populations as well as creating a HT protocol that addresses policies and procedures, screening tools, and community referrals.

Keywords: emergency medicine, human trafficking, organizational assessment, stages of change

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Authors: H. Heidari-Bafroui, B. Ribeiro, A. Charbaji, C. Anagnostopoulos, M. Faghri

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In this paper, we report the development of a portable and inexpensive infrared lightbox for improving the detection limits of paper-based phosphate devices. Commercial paper-based devices utilize the molybdenum blue protocol to detect phosphate in the environment. Although these devices are easy to use and have a long shelf life, their main deficiency is their low sensitivity based on the qualitative results obtained via a color chart. To improve the results, we constructed a compact infrared lightbox that communicates wirelessly with a smartphone. The system measures the absorbance of radiation for the molybdenum blue reaction in the infrared region of the spectrum. It consists of a lightbox illuminated by four infrared light-emitting diodes, an infrared digital camera, a Raspberry Pi microcontroller, a mini-router, and an iPhone to control the microcontroller. An iPhone application was also developed to analyze images captured by the infrared camera in order to quantify phosphate concentrations. Additionally, the app connects to an online data center to present a highly scalable worldwide system for tracking and analyzing field measurements. In this study, the detection limits for two popular commercial devices were improved by a factor of 4 for the Quantofix devices (from 1.3 ppm using visible light to 300 ppb using infrared illumination) and a factor of 6 for the Indigo units (from 9.2 ppm to 1.4 ppm) with repeatability of less than or equal to 1.2% relative standard deviation (RSD). The system also provides more granular concentration information compared to the discrete color chart used by commercial devices and it can be easily adapted for use in other applications.

Keywords: infrared lightbox, paper-based device, phosphate detection, smartphone colorimetric analyzer

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Authors: Shorena Pharjiani

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The Present empirical paper investigates the relationship between FDI and economic growth by 10 selected industries in 10 Central and Eastern European countries from the period 1995 to 2012. Different estimation approaches were used to explore the connection between FDI and economic growth, for example OLS, RE, FE with and without time dummies. Obtained empirical results leads to some main consequences: First, the Central and East European countries (CEEC) attracted foreign direct investment, which raised the productivity of industries they entered in. It should be concluded that the linkage between FDI and output growth by industries is positive and significant enough to suggest that foreign firm’s participation enhanced the productivity of the industries they occupied. There had been an endogeneity problem in the regression and fixed effects estimation approach was used which partially corrected the regression analysis in order to make the results less biased. Second, it should be stressed that the results show that time has an important role in making FDI operational for enhancing output growth by industries via total factor productivity. Third, R&D positively affected economic growth and at the same time, it should take some time for research and development to influence economic growth. Fourth, the general trends masked crucial differences at the country level: over the last 20 years, the analysis of the tables and figures at the country level show that the main recipients of FDI of the 11 Central and Eastern European countries were Hungary, Poland and the Czech Republic. The main reason was that these countries had more open door policies for attracting the FDI. Fifth, according to the graphical analysis, while Hungary had the highest FDI inflow in this region, it was not reflected in the GDP growth as much as in other Central and Eastern European countries.

Keywords: central and East European countries (CEEC), economic growth, FDI, panel data

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Authors: Alexandre H. Okano, Pedro M. D. Agrícola, Daniel G. Da S. Machado, Luiz I. Do N. Neto, Luiz F. Farias Junior, Paulo H. D. Nascimento, Rickson C. Mesquita, John F. Araujo, Eduardo B. Fontes, Hassan M. Elsangedy, Shinsuke Shimojo, Li M. Li

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The prefrontal cortex is involved in the reward system and the insular cortex integrates the afferent inputs arriving from the body’ systems and turns into feelings. Therefore, modulating neuronal activity in these regions may change individuals’ perception in a given situation such as exercise. We tested whether transcranial direct current stimulation (tDCS) change cerebral oxygenation and pleasure during exercise. Fourteen volunteer healthy adult men were assessed into five different sessions. First, subjects underwent to a maximum incremental test on a cycle ergometer. Then, subjects were randomly assigned to a transcranial direct current stimulation (2mA for 15 min) intervention in a cross over design in four different conditions: anode and cathode electrodes on T3 and Fp2 targeting the insular cortex, and Fpz and F4 targeting prefrontal cortex, respectively; and their respective sham. These sessions were followed by 30 min of moderate intensity exercise. Brain oxygenation was measured in prefrontal cortex with a near infrared spectroscopy. Perceived exertion and pleasure were also measured during exercise. The asymmetry in prefrontal cortex oxygenation before the stimulation decreased only when it was applied over this region which did not occur after insular cortex or sham stimulation. Furthermore, pleasure was maintained during exercise only after prefrontal cortex stimulation (P > 0.7), while there was a decrease throughout exercise (P < 0.03) during the other conditions. We conclude that tDCS over the prefrontal cortex changes brain oxygenation in ventromedial prefrontal cortex and maintains perceived pleasure during exercise. Therefore, this technique might be used to enhance effective responses related to exercise.

Keywords: affect, brain stimulation, dopamine neuromodulation, pleasure, reward, transcranial direct current stimulation

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Authors: Amit Kumar, Bhupendra Pratap Singh, Manoj Singh, Monika Punia, Krishan Kumar, V. K. Jain

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Ambient concentrations of volatile organic compounds (VOCs) were investigated in order to find out temporal variations and their ozone forming potentials (OFP) at rural site in Delhi National Capital Region during summer 2013. Sampling was performed for continuous five days, to identify the differences in working days and weekend VOCs concentration levels. Sampling and analytical procedure for VOCs were done using National Institute for Occupational Safety and Health (NIOSH) standard method. On each sampling day, VOCs samples were collected for 3-hours in the morning, afternoon and evening. There has been observed a noticeable contrast in the concentration of VOCs levels between working days and weekend. However, most of the VOCs showed diurnal fluctuations with higher concentrations in the morning and evening as compared to afternoon which might be due to change in meteorology. The results showed that mean toluene/benzene and m-/p-xylene/benzene ratios were higher in the afternoon while it was lower during morning and evening. The relative contribution of the VOCs to ozone formation, total propylene equivalent concentrations and OFP were calculated. Toluene was the most contributing organic contaminant to ozone formation as well as ambient VOCs concentrations. Results obtained in current study demonstrate that ozone formation at rural site in Delhi is probably limited by the emissions of VOCs.

Keywords: VOCs, rural, NIOSH, ozone forming potential, propylene equivalent concentration

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Authors: Marwan Khalil Qader, Arshad Mohammad Abdullah

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Antimicrobial resistance is a major cause of significant morbidity and mortality globally. Seven plant extracts (Plantago mediastepposa, Quercusc infectoria, Punic granatum, Thymus lcotschyana, Ginger officeinals, Rhus angustifolia and Cinnamon) were collected from different regions of Kurdistan region of Iraq. These plants’ extracts were dissolved in absolute ethanol and distillate water, after which they were assayed in vitro as an antimicrobial activity against Candida tropicalis, Candida albicanus, Candida dublinensis, Candida krusei and Candida glabrata also against 2 Gram-positive (Bacillus subtilis and Staphylococcus aureus) and 3 Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa and Klebsilla pneumonia). The antimicrobial activity was determined in ethanol extracts and distilled water extracts of these plants. The ethanolic extracts of Q. infectoria showed the maximum activity against all species of Candida fungus. The minimum inhibition zone of the Punic granatum ethanol extracts was 0.2 mg/ml for all microorganisms tested. Klebsilla pneumonia was the most sensitive bacterial strain to Quercusc infectoria and Rhus angustifolia ethanol extracts. Among both Gram-positive and Gram-negative bacteria tested with MIC of 0.2 mg/ml, the minimum inhibition zone of Ginger officeinals D. W. extracts was 0.2 mg/mL against Pseudomonas aeruginosa and Klebsilla pneumonia. The most sensitive bacterial strain to Thymus lcotschyana and Plantago mediastepposa D.W. extracts was S. aureus and E. coli.

Keywords: antimicrobial activity, pathogenic bacteria, plant extracts, chemical systems engineering

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Authors: S. Kealy, J. Louys, S. O’Connor

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The island archipelago that stretches between the continents of Sunda (Southeast Asia) and Sahul (Australia - New Guinea) and comprising much of modern-day Indonesia as well as Timor-Leste, represents the biogeographic region of Wallacea. The islands of Wallaea are significant archaeologically as they have never been connected to the mainlands of either Sunda or Sahul, and thus the colonization by early modern humans of these islands and subsequently Australia and New Guinea, would have necessitated some form of water crossings. Accurate palaeogeographic reconstructions of the Wallacean Archipelago for this time are important not only for modeling likely routes of colonization but also for reconstructing likely landscapes and hence resources available to the first colonists. Here we present five digital reconstructions of coastal outlines of Wallacea and Sahul (Australia and New Guinea) for the periods 65, 60, 55, 50, and 45,000 years ago using the latest bathometric chart and a sea-level model that is adjusted to account for the average uplift rate known from Wallacea. This data was also used to reconstructed island areal extent as well as topography for each time period. These reconstructions allowed us to determine the distance from the coast and relative elevation of the earliest archaeological sites for each island where such records exist. This enabled us to approximate how much effort exploitation of coastal resources would have taken for early colonists, and how important such resources were. These reconstructions also allowed us to estimate visibility for each island in the archipelago, and to model how intervisible each island was during the period of likely human colonisation. We demonstrate how these models provide archaeologists with an important basis for visualising this ancient landscape and interpreting how it was originally viewed, traversed and exploited by its earliest modern human inhabitants.

Keywords: Wallacea, palaeogeographic reconstructions, islands, intervisibility

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Authors: T. Qasim, B. El Masoud, D. Ailabouni

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This in vitro study focused on investigating the fatigue resistance of veneered zirconia molar crowns with different veneering ceramic thicknesses, simulating the relative wear depths under simulated cyclic loading. A mandibular first molar was prepared and then scanned using computer-aided design/computer-aided manufacturing (CAD/CAM) technology to fabricate 32 zirconia copings of uniform 0.5 mm thickness. The manufactured copings then veneered with 1.5 mm, 1.0 mm, 0.5 mm, and 0.0 mm representing 0%, 33%, 66%, and 100% relative wear of a normal ceramic thickness of 1.5 mm. All samples were thermally aged to 6000 thermo-cycles for 2 minutes with distilled water between 5 ˚C and 55 ˚C. The samples subjected to cyclic fatigue and fracture testing using SD Mechatronik chewing simulator. These samples are loaded up to 1.25x10⁶ cycles or until they fail. During fatigue, testing, extensive cracks were observed in samples with 0.5 mm veneering layer thickness. Veneering layer thickness 1.5-mm group and 1.0-mm group were not different in terms of resisting loads necessary to cause an initial crack or final failure. All ceramic zirconia-based crown restorations with varying occlusal veneering layer thicknesses appeared to be fatigue resistant. Fracture load measurement for all tested groups before and after fatigue loading exceeded the clinical chewing forces in the posterior region. In general, the fracture loads increased after fatigue loading and with the increase in the thickness of the occlusal layering ceramic.

Keywords: all ceramic, cyclic loading, chewing simulator, dental crowns, relative wear, thermally ageing

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Authors: Nitin Pipralia, Amit Kmar Sinha, Gudrun de Boeck

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Atmospheric carbon dioxide (CO2) concentrations have been increasing since the beginning of the industrial revolution due to combustion of fossils fuel and many anthropogenic means. As the number of scenarios assembled by the International Panel on Climate Change (IPCC) predict a rise of pCO2 from today’s 380 μatm to approximately 900 μatm until the year 2100 and a further rise of up to 1900 μatm by the year 2300. A rise in pCO2 results in more dissolution in ocean surface water which lead to cange in water pH, This phenomena of decrease in ocean pH due to increase on pCO2 is ocean acidification is considered a potential threat to the marine ecosystems and expected to affect fish as well as calcerious organisms. The situation may get worste when the stress of salinity adds on, due to migratory movement of fishes, where fish moves to different salinity region for various specific activities likes spawning and other. Therefore, to understand the interactive impact of these whole range of two important environmental abiotic stresses (viz. pCO2 ranging from 380 μatm, 900 μatm and 1900 μatm, along with salinity gradients of 32ppt, 10 ppt and 2.5ppt) on the ecophysiologal performance of fish, we investigated various biological adaptive response in European sea bass (Dicentrarchus labrax), a model estuarine teleost. Overall, we hypothesize that effect of ocean acidification would be exacerbate with shift in ambient salinity. Oxygen consumption, ammonia metabolism, iono-osmoregulation, energy budget, ion-regulatory enzymes, hormones and pH amendments in plasma were assayed as the potential indices of compensatory responses.

Keywords: ocean acidification, sea bass, pH climate change, salinity

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Authors: Sarah Ledoux

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This paper analyses the quantitative effects of political content consumption in social media platforms on self-reported ideological preference across the Latin American region. Initially praising the democratic potential of the internet and its social networking websites, digital politics scholars have transitioned their discourse to warning against the undemocratic side-effects it cultivates, such as hate speech, filter bubbles, and ideological polarisation. Holding technology solely responsible for political trends worldwide is an oversimplification of the factors influencing social change. Nonetheless, widespread use of social media in new democracies raises questions on the reproduction of recent trends that have been observed in the US and Western Europe. Through the analysis of ordered logistic regressions on data from the 2018 AmericasBarometer survey, this study examines the extent to which the relationship between the consumption of political content on social media is related to ideological polarisation in Latin America. The findings indicate that there is a close link between consumption of political information on social media, specifically on Facebook and WhatsApp, and ideological positioning on the extremes of the political left- and right-wings. This relation holds when controlling for individual-level demographic and attitudinal factors, as well as country-level effects. These results demonstrate with empirical evidence that viewing political content on social media has a significant positive effect on the likelihood that citizens position themselves on the extreme ends of the left-right ideological spectrum and implies that political polarisation is a phenomenon that accompanies politically driven social media use.

Keywords: Latin America, polarisation, political consumption, political ideology, social media, survey

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Authors: Ghadeer Jalloul, Nour Hijazi, Cassia Boyadjian, Hussein Awala, Mohammad N. Ahmad, ‎Ahmad Albadarin

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In this study, we applied Fe-sensitized TiO₂ supported over embryonic Beta zeolite (BEA) zeolite ‎for the photocatalytic degradation of Tetracycline (TC) antibiotic under visible light. Four different ‎samples having 20, 40, 60, and 100% w/w as a ratio of TiO₂/BEA were prepared. The ‎immobilization of solgel TiO₂ (33 m²/g) over BEA (390 m²/g) increased its surface area to (227 ‎m²/g) and enhanced its adsorption capacity from 8% to 19%. To expand the activity of TiO₂ ‎photocatalyst towards the visible light region (λ>380 nm), we explored two different metal ‎sensitization techniques with Iron ions (Fe³⁺). In the ion-exchange method, the substitutional cations ‎in the zeolite in TiO₂/BEA were exchanged with (Fe³⁺) in an aqueous solution of FeCl₃. In the ‎doping technique, solgel TiO₂ was doped with (Fe³⁺) from FeCl₃ precursor during its synthesis and ‎before its immobilization over BEA. (Fe-TiO₂/BEA) catalysts were characterized using SEM, XRD, ‎BET, UV-VIS DRS, and FTIR. After testing the performance of the various ion-exchanged catalysts ‎under blue and white lights, only (Fe-TiO₂/BEA 60%) showed better activity as compared to pure ‎TiO₂ under white light with 100 ppm initial catalyst concentration and 20 ppm TC concentration. As ‎compared to ion-exchanged (Fe-TiO₂/BEA), doped (Fe-TiO₂/BEA) resulted in higher photocatalytic ‎efficiencies under blue and white lights. The 3%-Fe-doped TiO₂/BEA removed 92% of TC ‎compared to 54% by TiO₂ under white light. The catalysts were also tested under real solar ‎irradiations. This improvement in the photocatalytic performance of TiO₂ was due to its higher ‎adsorption capacity due to BEA support combined with the presence of Iron ions that enhance the ‎visible light absorption and minimize the recombination effect by the charge carriers. ‎

Keywords: Tetracycline, photocatalytic degradation, immobilized TiO₂, zeolite, iron-doped TiO₂, ion-exchange

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Authors: Tri Nopiyanto, Rahardhyani Dwiannisa, Arief Ismaryanto

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One main issue for a certain region in order to achieve development is if the government that consists of the executive, legislative and judicial board are able to work together. However, there are certain conditions that these boards are the sources of conflict, especially between the executive and legislative board. One of the example of the conflict is between the Local Government and Legislative Board (DPRD) in the Province of Jakarta in 2015. The cause of this conflict is because of the occurrence of pokir (pokok pikiran or ideas of budgeting). Pokir is driven by a budgeting plan that is arranged by DPRD that is supposed to be sourced from the aspiration of the people and delivered 5 months before the legalization of Local Government Budget (APBD), but the current condition in Jakarta is that pokir is a project by DPRD members itself and delivered just 3 days before the legalization in order to facilitate the interests of the members of the legislative. This paper discusses how pokir happens and what factors caused it. This paper uses political budgeting theory by Andy Norton and Diane Elson to analyze the issue. The method used in this paper is qualitative to collect the data and solve the problem of this research. The methods involved are in depth interview, experimental questionnaire, and literature studies. Results of this research are that Pokir occurs because of the distribution of power among DPRD members, between parties, executive, and legislative board. Beside that, Pokir also occurs because of the lack of the people’s participation in budgeting process and monitoring. Other than that, this paper also found that pokir also happens because of the budgeting system that is not able to provide a clean budgeting process, so it enables the creation of certain slots to add pokir into the budgets. Pokir also affects the development of Jakarta that goes through stagnation. This research recommends the implementation of e-budgeting to prevent the occurrence of pokir itself in the Province of Jakarta.

Keywords: legislative and executive board, Jakarta, political budgeting, Pokir

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Authors: Laila Niklasson

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The aim of the study is to critically discuss how partner schools are engaged during Initial teacher education, ITE. The background is an experiment in Sweden where the practicum organization is reorganized due to a need to enhance quality during practicum. It is a national initiative from the government, supported by the National Agency of Education and lasts 2014-2019. The main features are concentration of students to school with a certain amount of mentors, mentors who have a mentor education and teachers with relevant subject areas and where there could be a mentor team with a leader at the school. An expected outcome is for example that the student teachers should be engaged in peer-learning. The schools should be supported by extra lectures from university teachers during practicum and also extra research projects where the schools should be engaged. A case study of one university based ITE was carried out to explore the consequences for the schools not selected. The result showed that from engaging x schools in a region, x was engaged. The schools are both in urban and rural areas, mainly in the latter. There is also a tendency that private schools are not engaged. On a unit level recruitment is perceived as harder for schools not engaged. In addition they cannot market themselves as ´selected school´ which can affect parent´s selection of school for their children. Also, on unit level, but with consequences for professional development, they are not selected for research project and thereby are not fully supported during school development. The conclusion is that from an earlier inclusive approach concerning professions where all teachers were perceived as possible mentors, there is a change to an exclusive approach where selected schools and selected teachers should be engaged. The change could be perceived as a change in governance mentality, but also in how professions are perceived, and development work is pursued.

Keywords: initial teacher education, practicum schools, profession, quality development

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Authors: John Okanda Okwaro

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Carbon (IV) oxide (CO₂) is emitted majorly from fossil fuel combustion and industrial production. The sources of interest of carbon (IV) oxide in the study area are mining activities, transport systems, and industrial processes. This study is aimed at building models that will help in monitoring the emissions within the study area. Three scenarios were discussed, namely: pessimistic scenario, business-as-usual scenario, and optimistic scenario. The result showed that there was a reduction in carbon dioxide concentration by approximately 50.5 ppm between March 2020 and January 2021 inclusive. This is majorly due to reduced human activities that led to decreased consumption of energy. Also, the CO₂ concentration trend follows the business-as-usual scenario (BAU) path. From the models, the pessimistic, business-as-usual, and optimistic scenarios give CO₂ concentration of about 545.9 ppm, 408.1 ppm, and 360.1 ppm, respectively, on December 31st, 2021. This research helps paint the picture to the policymakers of the relationship between energy sources and CO₂ emissions. Since the reduction in CO₂ emission was due to decreased use of fossil fuel as there was a decrease in economic activities, then if Kenya relies more on green energy than fossil fuel in the post-COVID-19 period, there will be more CO₂ emission reduction. That is, the CO₂ concentration trend is likely to follow the optimistic scenario path, hence a reduction in CO₂ concentration of about 48 ppm by the end of the year 2021. This research recommends investment in solar energy by energy-intensive companies, mine machinery and equipment maintenance, investment in electric vehicles, and doubling tree planting efforts to achieve the 10% cover.

Keywords: forecasting, greenhouse gas, green energy, hierarchical data format

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Authors: Sudhir Kumar, V. R. Sinha

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Water in oil topical microemulsions of 5-FU were developed and optimized using face centered central composite design. Topical w/o microemulsion of 5-FU were prepared using sorbitan monooleate (Span 80), polysorbate 80 (Tween 80), with different oils such as oleic acid (OA), triacetin (TA), and isopropyl myristate (IPM). The ternary phase diagrams designated the microemulsion region and face centered central composite design helped in determining the effects of selected variables viz. type of oil, smix ratio and water concentration on responses like drug content, globule size and viscosity of microemulsions. The CCD design exhibited that the factors have statistically significant effects (p<0.01) on the selected responses. The actual responses showed excellent agreement with the predicted values as suggested by the CCD with lower residual standard error. Similarly, the optimized values were found within the range as predicted by the model. Furthermore, other characteristics of microemulsions like pH, conductivity were investigated. For the optimized microemulsion batch, ex-vivo skin flux, skin irritation and retention studies were performed and compared with marketed 5-FU formulation. In ex vivo skin permeation studies, higher skin retention of drug and minimal flux was achieved for optimized microemulsion batch then the marketed cream. Results confirmed the actual responses to be in agreement with predicted ones with least residual standard errors. Controlled release of drug was achieved for the optimized batch with higher skin retention of 5-FU, which can further be utilized for the treatment of many dermatological disorders.

Keywords: 5-FU, central composite design, microemulsion, ternanry phase diagram

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Authors: Arti Singh, Carolyn Jenkins, Oyedunni S. Arulogun, Mayowa O. Owolabi, Fred S. Sarfo, Bruce Ovbiagele, Enzinne Sylvia

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Background: Stroke, the leading cause of adult-onset disability and the second leading cause of death, is a major public health concern particularly pertinent in Sub-Saharan Africa (SSA), where nearly 80% of all global stroke mortalities occur. The Stroke Investigative Research and Education Network (SIREN) seeks to comprehensively characterize the genomic, sociocultural, economic, and behavioral risk factors for stroke and to build effective teams for research to address and decrease the burden of stroke and other non communicable diseases in SSA. One of the first steps to address this goal was to effectively engage the communities that suffer the high burden of disease in SSA. This study describes how the SIREN project engaged six sites in Ghana and Nigeria over the past three years, describing the community engagement activities that have arisen since inception. Aim: The aim of community engagement (CE) within SIREN is to elucidate information about knowledge, attitudes, beliefs, and practices (KABP) about stroke and its risk factors from individuals of African ancestry in SSA, and to educate the community about stroke and ways to decrease disabilities and deaths from stroke using socioculturally appropriate messaging and messengers. Methods: Community Advisory Board (CABs), Focus Group Discussions (FGDs) and community outreach programs. Results: 27 FGDs with 168 participants including community heads, religious leaders, health professionals and individuals with stroke among others, were conducted, and over 60 CE outreaches have been conducted within the SIREN performance sites. Over 5,900 individuals have received education on cardiovascular risk factors and about 5,000 have been screened for cardiovascular risk factors during the outreaches. FGDs and outreach programs indicate that knowledge of stroke, as well as risk factors and follow-up evidence-based care is limited and often late. Other findings include: 1) Most recognize hypertension as a major risk factor for stroke. 2) About 50% report that stroke is hereditary and about 20% do not know organs affected by stroke. 3) More than 95% willing to participate in genetic testing research and about 85% willing to pay for testing and recommend the test to others. 4) Almost all indicated that genetic testing could help health providers better treat stroke and help scientists better understand the causes of stroke. The CABs provided stakeholder input into SIREN activities and facilitated collaborations among investigators, community members and stakeholders. Conclusion: The CE core within SIREN is a first-of-its kind public outreach engagement initiative to evaluate and address perceptions about stroke and genomics by patients, caregivers, and local leaders in SSA and has implications as a model for assessment in other high-stroke risk populations. SIREN’s CE program uses best practices to build capacity for community-engaged research, accelerate integration of research findings into practice and strengthen dynamic community-academic partnerships within our communities. CE has had several major successes over the past three years including our multi-site collaboration examining the KABP about stroke (symptoms, risk factors, burden) and genetic testing across SSA.

Keywords: community advisory board, community engagement, focus groups, outreach, SSA, stroke

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Authors: Nishi Bhuvandas, P. V. Timbadiya, P. L. Patel, P. D. Porey

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Recent perceived climate variability raises concerns with unprecedented hydrological phenomena and extremes. Distribution and circulation of the waters of the Earth become increasingly difficult to determine because of additional uncertainty related to anthropogenic emissions. According to the sixth Intergovernmental Panel on Climate Change (IPCC) Technical Paper on Climate Change and water, changes in the large-scale hydrological cycle have been related to an increase in the observed temperature over several decades. Although many previous research carried on effect of change in climate on hydrology provides a general picture of possible hydrological global change, new tools and frameworks for modelling hydrological series with nonstationary characteristics at finer scales, are required for assessing climate change impacts. Of the downscaling techniques, dynamic downscaling is usually based on the use of Regional Climate Models (RCMs), which generate finer resolution output based on atmospheric physics over a region using General Circulation Model (GCM) fields as boundary conditions. However, RCMs are not expected to capture the observed spatial precipitation extremes at a fine cell scale or at a basin scale. Statistical downscaling derives a statistical or empirical relationship between the variables simulated by the GCMs, called predictors, and station-scale hydrologic variables, called predictands. The main focus of the paper is on the need for using statistical downscaling techniques for projection of local hydrometeorological variables under climate change scenarios. The projections can be then served as a means of input source to various hydrologic models to obtain streamflow, evapotranspiration, soil moisture and other hydrological variables of interest.

Keywords: climate change, downscaling, GCM, RCM

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