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Extraction of M. paradisiaca L. Inflorescences Using Compressed Propane
Authors: Michele C. Mesomo, Madeline de Souza Correa, Roberta L. Kruger, Luis R. S. Kanda, Marcos L. Corazza
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Natural extracts of plants have been used for many years for different purposes and recently they have been screened for their potential use as alternative remedies and food preservatives. Inflorescences of M. paradisiaca L., also known as the heart of the banana, have great economic interest due to its fruit. All parts of the banana are used for many different purposes, including use in folk medicine. The use of extraction via supercritical technology has grown in recent years, though it is still necessary to obtain experimental information for the construction of industrial plants. This work reports the extraction of Musa paradisiaca L. using compressed propane as solvent. The effects of the supercritical extraction conditions, pressure and temperature on the yield were evaluated. The raw material, inflorescences banana, was dried at 313.15 K and milled. The particle size used for the packaging of the extraction cell was 12 mesh (23.5%), 16 mesh (23.5%), 32 mesh (34.5%), 48 mesh (18.5%). The extractions were performed in a laboratory scale unit at pressures of 3.0 MPa, 6.5 MPa and 10.0 MPa and at 308.15 K, 323.15 K and 338.15 K. The operating conditions tested achieved a maximum yield of 2.94 wt% for the CO2 extraction at 10.0 MPa and 338.15 K, higher pressure and temperature. The lower yield, 2.29 wt%, was obtained in the condition of lower pressure and higher temperature. Temperature presented significant and positive effect on the extraction yield with supercritical CO2, while pressure had no effect on the yield. The overall extraction curves showed typical behavior obtained for the supercritical extraction procedure and and reached a constant extraction rate of about 80 to 100 min. The largest amount of extract was obtained at the beginning of the process, within 10 to 60 min.Keywords: banana, natural products, supercritical extraction, temperature
Procedia PDF Downloads 619Comparison of Bioactive Compound Content in Egg Yolk Oil Extracted from Eggs Obtained from Different Laying Hen Housing Systems
Authors: Aleksandrs Kovalcuks
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Egg yolk oil is a natural source of bioactive compounds such as unsaturated fatty acids, oil soluble vitamins, pigments and others. Bioactive compound content in egg yolk oil depends from its content in eggs, from which oil was extracted. Many studies show that bioactive compound content in egg is correlated to the content of these compounds in hen feed, but there is also an opinion that hen housing systems also have influence on egg chemical content. The aim of this study was to determine which factor, laying hen housing system or hen diet, has a primary influence on bioactive compound content in egg yolk oil. The egg yolk oil was extracted from eggs obtained from 4 different hen housing systems: cage, barn and two groups of free range. All hens were fed with commercially produced compound feed except one group of free range hens which get free diet – pastured hens. Extracted egg yolk oils were analyzed for fatty acids, oil soluble vitamins and β-carotene content. α-tocopherol, ergocalcipherol and polyunsaturated fatty acid content in egg yolk oil was higher from eggs obtained from all housing systems where hens were fed with commercial compound feed. β-carotene and retinol content in egg yolk oils from free range free diet eggs was significantly (p>0.05) higher that from other eggs because hens have access to green forage. Hen physical activity in free range housing systems decreases content of some bioactive compound in egg yolk oil.Keywords: egg yolk oil, vitamins, caged eggs, free range
Procedia PDF Downloads 469Normal Hematopoietic Stem Cell and the Toxic Effect of Parthenolide
Authors: Alsulami H., Alghamdi N., Alasker A., Almohen N., Shome D.
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Most conventional chemotherapeutic agents which are used for the treatment of cancers not only eradicate cancer cells but also affect normal hematopoietic Stem cells (HSCs) that leads to severe pancytopenia during treatment. Therefore, a need exists for novel approaches to treat cancer without or with minimum effect on normal HSCs. Parthenolide (PTL), a herbal product occurring naturally in the plant Feverfew, is a potential new chemotherapeutic agent for the treatment of many cancers such as acute myeloid leukemia (AML) and chronic lymphocytic leukemia (CLL). In this study we investigated the effect of different PTL concentrations on the viability of normal HSCs and also on the ability of these cells to form colonies after they have been treated with PTL in vitro. Methods: In this study, 24 samples of bone marrow and cord blood were collected with consent, and mononuclear cells were separated using density gradient separation. These cells were then exposed to various concentrations of PTL for 24 hours. Cell viability after culture was determined using 7ADD in a flow cytometry test. Additionally, the impact of PTL on hematopoietic stem cells (HSCs) was evaluated using a colony forming unit assay (CFU). Furthermore, the levels of NFҝB expression were assessed by using a PE-labelled anti-pNFκBP65 antibody. Results: this study showed that there was no statistically significant difference in the percentage of cell death between untreated and PTL treated cells with 5 μM PTL (p = 0.7), 10 μM PTL (p = 0.4) and 25 μM (p = 0.09) respectively. However, at higher doses, PTL caused significant increase in the percentage of cell death. These results were significant when compared to untreated control (p < 0.001). The response of cord blood cells (n=4) on the other hand was slightly different from that for bone marrow cells in that the percentage of cell death was significant at 100 μM PTL. Therefore, cord blood cells seemed more resistant than bone marrow cells. Discussion &Conclusion: At concentrations ≤25 μM PTL has a minimum or no effect on HSCs in vitro. Cord blood HSCs are more resistant to PTL compared to bone marrow HSCs. This could be due to the higher percentage of T-lymphocytes, which are resistant to PTL, in CB samples (85% in CB vs. 56% in BM. Additionally, CB samples contained a higher proportion of CD34+ cells, with 14.5% of brightly CD34+ cells compared to only 1% in normal BM. These bright CD34+ cells in CB were mostly negative for early-stage stem cell maturation antigens, making them young and resilient to oxidative stress and high concentrations of PTL.Keywords: stem cell, parthenolide, NFKB, CLL
Procedia PDF Downloads 56Survey Based Data Security Evaluation in Pakistan Financial Institutions against Malicious Attacks
Authors: Naveed Ghani, Samreen Javed
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In today’s heterogeneous network environment, there is a growing demand for distrust clients to jointly execute secure network to prevent from malicious attacks as the defining task of propagating malicious code is to locate new targets to attack. Residual risk is always there no matter what solutions are implemented or whet so ever security methodology or standards being adapted. Security is the first and crucial phase in the field of Computer Science. The main aim of the Computer Security is gathering of information with secure network. No one need wonder what all that malware is trying to do: It's trying to steal money through data theft, bank transfers, stolen passwords, or swiped identities. From there, with the help of our survey we learn about the importance of white listing, antimalware programs, security patches, log files, honey pots, and more used in banks for financial data protection but there’s also a need of implementing the IPV6 tunneling with Crypto data transformation according to the requirements of new technology to prevent the organization from new Malware attacks and crafting of its own messages and sending them to the target. In this paper the writer has given the idea of implementing IPV6 Tunneling Secessions on private data transmission from financial organizations whose secrecy needed to be safeguarded.Keywords: network worms, malware infection propagating malicious code, virus, security, VPN
Procedia PDF Downloads 360Correlation between Nutritional Status and Length of Stay and Hospital Costs in Critical Care and IPD Patients of Somdech Phra Debaratana Medical Center (SDMC), Faculty of Medicine, Ramathibodi Hospital
Authors: Nuttapimon Bhirommuang, Kulapong Jayanama
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Background: Prevalence of malnutrition in hospitalized patient is higher than general population. As a result of the unawareness of consequence and the more concerning in the other aspects of care, many patients with high risk of malnutrition are unrecognized. Even if malnutrition has been identified as affecting in many patient outcomes, the impact may differ in each population and group of patients. Objectives: The aims of this study were to examine the association between the nutritional status and the length of stay and hospital costs in hospitalized patients, to investigate the factors related these outcomes and to determine the frequency of malnutrition in hospitals. Method: This retrospective cohort study enrolled all patients aged 15 years old or older and admitted in SDMC, Ramathibodi Hospital between 1st January 2016 and 30th September 2016. The nutritional status assessment by Nutrition Alert Form (NAF) was performed by well-trained nurses in all patients at admission. Baseline characteristics were recorded. Length of stay and hospital costs were collected during their hospitalization. Univariate analysis, nonparametric rank test, Kruskal-Wallis test were used to compare means in the case of nonnormally and noncontinuously distributed data. Chi-square used to analyze categorical variables, the nutritional status and the length of stay and hospital costs and identify possible confounding factors (data were analyzed using SPSS version 18.0). Result: Of the 2,906 patients, 3.9% were severe malnutrition (NAF-C score > 10) and 11.4% were moderate malnutrition (NAF-B score 6 - 10). Both length of stay and hospital costs were found significantly higher in more severe malnutrition group (p < 0.001), NAF = A: 3.21 days, 95% CI 3.06-3.35 and 111,544.25 THB, 95% CI 106,994.41 – 116,094.1; NAF = B: 7.54 days, 95% CI 6.32 – 8.76 and 162,302.4 THB, 95% CI 129,557.88 – 195,046.92; NAF =C: 14.77 days, 95% CI 11.34 – 18.2 and 323,572.11 THB, 95% CI 226,958.1 – 420,096.13 (1 THB = 0.03019 USD). Age of each nutritional status group had also significant increase from NAF A to NAF C (p < 0.001): 55.07, 67.03 and 73.88 years old, respectively. Conclusion: The prevalence of malnutrition in Ramathibodi hospital is voluminous. Severe malnutrition screening by NAF is significantly correlated with worse clinical outcome, especially higher length of stay and hospital costs. Elderly is also a significant factor which correlates with malnutrition. The results of this study could change the awareness of health personnel and the practice protocol. Moreover, the further study concerning nutritional support in high-risk group of malnutrition is ongoing to confirm this hypothesis.Keywords: malnutrition, NAF, length of stay, hospital costs
Procedia PDF Downloads 275A Study on the Assessment of Prosthetic Infection after Total Knee Replacement Surgery
Authors: Chun-Lang Chang, Chun-Kai Liu
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In this study, the patients that have undergone total knee replacement surgery from the 2010 National Health Insurance database were adopted as the study participants. The important factors were screened and selected through literature collection and interviews with physicians. Through the Cross Entropy Method (CE), Genetic Algorithm Logistic Regression (GALR), and Particle Swarm Optimization (PSO), the weights of the factors were obtained. In addition, the weights of the respective algorithms, coupled with the Excel VBA were adopted to construct the Case Based Reasoning (CBR) system. The results through statistical tests show that the GALR and PSO produced no significant differences, and the accuracy of both models were above 97%. Moreover, the area under the curve of ROC for these two models also exceeded 0.87. This study shall serve as a reference for medical staff as an assistance for clinical assessment of infections in order to effectively enhance medical service quality and efficiency, avoid unnecessary medical waste, and substantially contribute to resource allocations in medical institutions.Keywords: Case Based Reasoning, Cross Entropy Method, Genetic Algorithm Logistic Regression, Particle Swarm Optimization, Total Knee Replacement Surgery
Procedia PDF Downloads 326Study of Pulmonary Function Test of over the 40 Years Adults in Ulaanbaatar
Authors: D. Densenbal, Ts. Naidansuren, M. Oyunchimeg, Ts. Manaljav, D. Udval, L. Khosbayar, Kh. Solongo, D. Ichinnorov, B. Solongo
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Background: The rapid economic growth and to the common use of smoky fuel such as coal in the small traditional houses (Ger) in Mongolia is worsening its air pollution problem. In addition, the smoking rate is considered to be high. Despite these conditions, few prevalence studies of COPD epidemiology and diagnose have been performed in Mongolia. The spirometric test is a widely used diagnose for COPD. Aims: Healthy and over the 40 aged adults were evaluated of Pulmonary function test in Ulaanbaatar. Methods: Healthy, over the 40 aged residences were admitted for this study from II sub-district, in Khan-Uul district of Ulaanbaatar city. In this cross-sectional study. Health information was collected 184 subjects between 01-03 July in 2013; spirometry device was named Hichest–105 Japan that was employed for this study. Studies were using the acceptability standards outlined, and data were compared with personal reference data generated on Asian subjects which were performed abnormally to evaluated by global initiative obstructive lung decreases (GOLD). Data were analyzed using SPSS 20 software. Results: A total of 134 subjects (age 52.9±9.8, man 32.8%) were performed PFT which were interpreted normal 73.9% (sum of man 65.0% and woman 79.4% ), abnormal 26.1% which were typed obstruction 17.2% (23), restriction 6% (8), mixed 3% (4). Airflow obstruction were determined in all man 25% (11), woman 13.3% (12) which were classified mild 43.4% (man 54.5%, woman 33.3%), moderate 52.2% (36.3% vs. 66.7%) and severe 4.3% man 1 GOLD degree. Undetermined a very severe obstruction. Normal PFT subjects were compared a group of gender and age group which man was significantly higher than the women (p<0.05). Age group of PFT decrease was no difference in gender (p>0.05) also no difference in BMI (p>0.05). Normal PFT subjects were compared with predicted values were used to Asian population which was significantly lower than FEV1 (0.15±0.36 l), PEF (1.92±1.31 l) and same deference occurred man (FEV1 0.19±0.42 l, PEF 2.04±1.64), women (0.14±0.33 l vs. 1.86±1.15 l). The decrease of FEV1 was defined in over the 60 age group higher than other age groups. Conclusion: Not only observed an air flow limitation prevalence dominance in all case but also COPD prevalence diagnosed man were higher than women. Normal PFT subjects were compared with predicted values were used to Asian population which was significant air flow limitation started early.Keywords: PFT, obstruction, FEV1, COPD
Procedia PDF Downloads 219Factors Associated with Ketamine Use in Pancreatic Cancer Patient in a Single Hospice Center
Authors: Kyung Min Kwom, Young Joo Lee
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Purpose: Up to 90% of pancreatic cancer patient suffer from neuropathic pain. In palliative care setting, pain control in a pancreatic cancer patient is one of the major goals. Ketamine is a NMDA receptor antagonist effective in neuropathic pain. Also, there have been studies about opioid sparing effect of ketamine. This study was held in palliative care unit among pancreatic cancer patients to find out the factors related to ketamine use and the opioid sparing effect. Methods: Medical records of pancreatic cancer patients admitted to St. Mary’s hospital palliative care unit from 2013.1 to 2014.12 were reviewed. Patients were divided into two categories according to ketamine use. Also, opioid use before and after ketamine use was compared in ketamine group. Results: Compared to non ketamine use group, patients in ketamine group required a higher dose of opioid. Total opioid dose, daily opioid dose, number of daily rescue medication, daily average rescue dose were statistically significantly higher in ketamine group. Opioid requirement was increased after ketamine administration. Conclusion: In this study, ketamine group required more opioid. Ketamine is frequently considered in patients with severe pain, requiring high amount of opioid. Also, ketamine did not have an opioid sparing effect. Future studies about palliative use of ketamine in a larger number of patients are required.Keywords: ketamine, opioid sparing, palliative care, pancreatic cancer
Procedia PDF Downloads 236Phytoplankton of the Atlantic Ocean off Lagos
Authors: Ikenna Charles Onyema, Prince Tolut Bako
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A study was carried out in the Atlantic Ocean off the Lighthouse Beach, Lagos. There were monthly and spatial variations in physical and chemical characteristics of the neritic ocean (August-December, 2014). Mean and standard deviation values for air temperature were 27. 67, ± 2.98 oC, water temperature (28.37 ± 1.88), pH (7.85 ± 0.17), Conductivity (44738.75 ± 6262.76 µS/cm), Total dissolved solids (29236.71 ± 4273.30 mg/L), Salinity (27.11 ± 3.91 ‰), Alkalinity (126.99 ± 42.81 mg/L) and Chloride (15056. 67 ± 2165.78 mg/L). Higher estimates were recorded in the dry than wet months for these characteristics. On the other hand, reducing values were recorded for Acidity (2.34 ± 0.63 mg/L), Total hardness (4711.98 ± 691.50 mg/L), Phosphate (1.1 ± 0.78 mg/L), Sulphate (2601.99 ± 447.04 mg/L) and Nitrate (0.12 ± 0.06 mg/L). Values for Total suspended solids and Biological oxygen demand values were low ( < 1mg/L). Twenty-one species of phytoplankton were recorded. Diatoms recorded 80.92% and were the dominant group. Hemidiscus cuneiformis, Coscinodiscus centralis, Coscinodiscus lineatus, Coscinodiscus radiatus and Oscillatoria limosa were more frequently occurring species. Biddulphia sinensis and four species of Ceratium, were representatives of the dry season. The dry season also recorded comparatively higher individuals of phytoplankton than the wet season. Spirogyra sp. (green algae) appeared only in the wet season. Species abundance (N) was highest in December at Station 1 (13.15%) (dry season) and lowest in August (wet season) at Station 3 (2.96%). The physico-chemical factors and phytoplankton reflected a tropical unpolluted neritic oceanic environment.Keywords: sea, physico-chemistry, micro-algae, lighthouse beach
Procedia PDF Downloads 230Innovation Eco-Systems and Cities: Sustainable Innovation and Urban Form
Authors: Claudia Trillo
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Regional innovation eco-ecosystems are composed of a variety of interconnected urban innovation eco-systems, mutually reinforcing each other and making the whole territorial system successful. Combining principles drawn from the new economic growth theory and from the socio-constructivist approach to the economic growth, with the new geography of innovation emerging from the networked nature of innovation districts, this paper explores the spatial configuration of urban innovation districts, with the aim of unveiling replicable spatial patterns and transferable portfolios of urban policies. While some authors suggest that cities should be considered ideal natural clusters, supporting cross-fertilization and innovation thanks to the physical setting they provide to the construction of collective knowledge, still a considerable distance persists between regional development strategies and urban policies. Moreover, while public and private policies supporting entrepreneurship normally consider innovation as the cornerstone of any action aimed at uplifting the competitiveness and economic success of a certain area, a growing body of literature suggests that innovation is non-neutral, hence, it should be constantly assessed against equity and social inclusion. This paper draws from a robust qualitative empirical dataset gathered through 4-years research conducted in Boston to provide readers with an evidence-based set of recommendations drawn from the lessons learned through the investigation of the chosen innovation districts in the Boston area. The evaluative framework used for assessing the overall performance of the chosen case studies stems from the Habitat III Sustainable Development Goals rationale. The concept of inclusive growth has been considered essential to assess the social innovation domain in each of the chosen cases. The key success factors for the development of the Boston innovation ecosystem can be generalized as follows: 1) a quadruple helix model embedded in the physical structure of the two cities (Boston and Cambridge), in which anchor Higher Education (HE) institutions continuously nurture the Entrepreneurial Environment. 2) an entrepreneurial approach emerging from the local governments, eliciting risk-taking and bottom-up civic participation in tackling key issues in the city. 3) a networking structure of some intermediary actors supporting entrepreneurial collaboration, cross-fertilization and co-creation, which collaborate at multiple-scales thus enabling positive spillovers from the stronger to the weaker contexts. 4) awareness of the socio-economic value of the built environment as enabler of cognitive networks allowing activation of the collective intelligence. 5) creation of civic-led spaces enabling grassroot collaboration and cooperation. Evidence shows that there is not a single magic recipe for the successful implementation of place-based and social innovation-driven strategies. On the contrary, the variety of place-grounded combinations of micro and macro initiatives, embedded in the social and spatial fine grain of places and encompassing a diversity of actors, can create the conditions enabling places to thrive and local economic activities to grow in a sustainable way.Keywords: innovation-driven sustainable Eco-systems , place-based sustainable urban development, sustainable innovation districts, social innovation, urban policie
Procedia PDF Downloads 111Comparative Evaluation of Different Extenders and Sperm Protectors to Keep the Spermatozoa Viable for More than 24 Hours
Authors: A. M. Raseona, D. M. Barry, T. L. Nedambale
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Preservation of semen is an important process to ensure that semen quality is sufficient for assisted reproductive technology. This study evaluated the effectiveness of different extenders to preserve Nguni bull semen stored at controlled room temperature 24 °C for three days, as an alternative to frozen-thawed semen straws used for artificial insemination. Semen samples were collected from two Nguni bulls using an electro-ejaculator and transported to the laboratory for evaluation. Pooled semen was aliquot into three extenders Triladyl, Ham’s F10 and M199 at a dilution ratio of 1:4 then stored at controlled room temperature 24 °C. Sperm motility was analysed after 0, 24, 48 and 72 hours. Morphology and viability were analysed after 72 hours. The study was replicated four times and data was analysed by analysis of variance (ANOVA). Triladyl showed higher viability percentage and consistent total motility for three days. Ham’s F10 showed higher progressive motility compared to the other extenders. There was no significant difference in viability between Ham’s F10 and M199. No significant difference was also observed in total abnormality between the two Nguni bulls. In conclusion, Nguni semen can be preserved in Triladyl or Ham’s F10 and M199 culture media stored at 24 °C and stay alive for three days. Triladyl proved to be the best extender showing high viability and consistency in total motility as compared to Ham’s F10 and M199.Keywords: bull semen, artificial insemination, Triladyl, Ham’s F10, M199, viability
Procedia PDF Downloads 502Study of Microstructure and Mechanical Properties Obtained by FSW of Similar and Dissimilar Non-Ferrous Alloys Used in Aerospace and Automobile Industry
Authors: Ajay Sidana, Kulbir Singh Sandhu, Balwinder Singh Sidhu
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Joining of dissimilar non-ferrous alloys like aluminium and magnesium alloys becomes important in various automobile and aerospace applications due to their low density and good corrosion resistance. Friction Stir Welding (FSW), a solid state joining process, successfully welds difficult to weld similar and dissimilar aluminum and magnesium alloys. Two tool rotation speeds were selected by keeping the transverse speed constant to weld similar and dissimilar alloys. Similar(Al to Al) and Dissimilar(Al to Mg) weld joints were obtained by FSW. SEM scans revealed that higher tool rotation fragments the coarse grains of base material into fine grains in the weld zone. Also, there are less welding defects in weld joints obtained with higher tool rotation speed. The material of dissimilar alloys was mixed with each other forming recrystallised new intermetallics. There was decrease in hardness of similar weld joint however there is significant increase in hardness of weld zone in case of dissimilar weld joints due to stirring action of tool and formation of inter metallics. Tensile tests revealed that there was decrease in percentage elongation in both similar and dissimilar weld joints.Keywords: aluminum alloys, magnesium alloys, friction stir welding, microstructure, mechanical properties
Procedia PDF Downloads 458Prognostic Value of C-Reactive Protein (CRP) in SARS-CoV-2 Infection: A Simplified Biomarker of COVID-19 Severity in Sub-Saharan Africa
Authors: Teklay Gebrecherkos, Mahmud Abdulkader, Tobias Rinke De Wit, Britta C. Urban, Feyissa Chala, Yazezew Kebede, Dawit Welday
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Background: C-reactive protein (CRP) levels are a reliable surrogate for interleukin-6 bioactivity that plays a pivotal role in the pathogenesis of cytokine storm associated with severe COVID-19. There is a lack of data on the role of CRP as a determinant of COVID-19 severity status in the African context. Methods: We determined the longitudinal kinetics of CRP levels on 78 RT-PCR-confirmed COVID-19 patients (49 non-severe and 29 severe cases) and 50 PCR-negative controls. Results: COVID-19 patients had overall significantly elevated CRP at baseline when compared to PCR-negative controls [median 11.1 (IQR: 2.0-127.8) mg/L vs. 0.9 (IQR: 0.5-1.9) mg/L; p=0.0004)]. Moreover, severe COVID-19 patients had significantly higher median CRP levels than non-severe cases [166.1 (IQR: 48.6-332.5) mg/L vs. 2.4 (IQR: 1.2-7.6) mg/L; p<0.00001)]. In addition, persistently elevated levels of CRP were exhibited among those with comorbidities and higher age groups. Area under receiver operating characteristic curve (AUC) analysis of CRP levels distinguished PCR-confirmed COVID-19 patients from the ones with PCR-negative non-COVID-19 individuals, with an AUC value of 0.77 (95% CI: 0.68-0.84; p=0.001). Moreover, it clearly distinguished severe from non-severe COVID-19 patients, with an AUC value of 0.83 (95% CI: 0.73-0.91). After adjusting for age and the presence of comorbidities, CRP levels above 30 mg/L were significantly associated with an increased risk of developing severe COVID-19 (adjusted relative risk 3.99 (95%CI: 1.35-11.82; p=0.013). Conclusions: Determining CRP levels in COVID-19 patients in African settings may provide a simple, prompt, and inexpensive assessment of the severity status at baseline and monitoring of treatment outcomes.Keywords: CRP, COVID-19, SARS-CoV-2, biomarker
Procedia PDF Downloads 87Impact of Land Ownership on Rangeland Condition in the Gauteng Province, South Africa
Authors: N. L. Letsoalo, H. T. Pule, J. T. Tjelele, N. R. Mkhize, K. R. Mbatha
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Rangelands are major feed resource for livestock farming in South Africa, despite being subjected to different forms of degradation. These forms of degradation are as a result of inappropriate veld and livestock management practices such as excessive stocking rates. While information on judicious veld management is available, adoption of appropriate practices is still unsatisfactory and seems to depend partly on the type of land ownership of farmers. The objectives of this study were to; (I) compare rangeland condition (species richness, basal cover, veld condition score, and herbaceous biomass) among three land ownership types (leased land, communal land and private land), and (II) determine the relationships between veld condition score (%) and herbaceous biomass (kg DM/ha) production. Vegetation was assessed at fifty farms under different land use types using nearest plant technique. Grass species composition and forage value were estimated using PROC FREQ procedure of SAS 9.3. A one-way ANOVA was used to determine significant differences (P < 0.05) in species richness, basal cover, veld condition (%) large stock units, grazing capacity and herbaceous biomass production among the three grazing systems. A total of 28 grass species were identified, of which 95% and 5% were perennials and annuals, respectively. The most commonly distributed and highly palatable grass species, Digitaria eriantha had significantly higher frequency under private owned lands (32.3 %) compared to communal owned lands (12.3%). There were no significant difference on grass species richness and basal cover among land ownership types (P > 0.05). There were significant differences on veld condition score and biomass production (P < 0.05). Private lands had significantly higher (69.63%) veld condition score than leased (56.07%) and communal lands (52.55%). Biomass production was significantly higher (± S.E.) 2990.30 ± 214 kg DM/ha on private owned lands, compared to leased lands 2069.85 ± 196 kg DM/ha and communal lands 1331.04 ± 102 kg DM/ha. Biomass production was positively correlated with rangeland condition (r = 0.895; P < 0.005). These results suggest that rangeland conditions on communal and leased lands are in poor condition than those on private lands. More research efforts are needed to improve management of rangelands in communal and leased land in Gauteng province.Keywords: grazing, herbaceous biomass, management practices, species richness
Procedia PDF Downloads 172Design and Fabrication of ZSO Nanocomposite Thin Film Based NO2 Gas Sensor
Authors: Bal Chandra Yadav, Rakesh K. Sonker, Anjali Sharma, Punit Tyagi, Vinay Gupta, Monika Tomar
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In the present study, ZnO doped SnO2 thin films of various compositions were deposited on the surface of a corning substrate by dropping the two sols containing the precursors for composite (ZSO) with subsequent heat treatment. The sensor materials used for selective detection of nitrogen dioxide (NO2) were designed from the correlation between the sensor composition and gas response. The available NO2 sensors are operative at very high temperature (150-800 °C) with low sensing response (2-100) even in higher concentrations. Efforts are continuing towards the development of NO2 gas sensor aiming with an enhanced response along with a reduction in operating temperature by incorporating some catalysts or dopants. Thus in this work, a novel sensor structure based on ZSO nanocomposite has been fabricated using chemical route for the detection of NO2 gas. The structural, surface morphological and optical properties of prepared films have been studied by using X-ray diffraction (XRD), Atomic force microscopy (AFM), Transmission electron microscope (TEM) and UV-visible spectroscopy respectively. The effect of thickness variation from 230 nm to 644 nm of ZSO composite thin film has been studied and the ZSO thin film of thickness ~ 460 nm was found to exhibit the maximum gas sensing response ~ 2.1×103 towards 20 ppm NO2 gas at an operating temperature of 90 °C. The average response and recovery times of the sensor were observed to be 3.51 and 6.91 min respectively. Selectivity of the sensor was checked with the cross-exposure of vapour CO, acetone, IPA, CH4, NH3 and CO2 gases. It was found that besides the higher sensing response towards NO2 gas, the prepared ZSO thin film was also highly selective towards NO2 gas.Keywords: ZSO nanocomposite thin film, ZnO tetrapod structure, NO2 gas sensor, sol-gel method
Procedia PDF Downloads 344Effect of Environmental Factors on Photoreactivation of Microorganisms under Indoor Conditions
Authors: Shirin Shafaei, James R. Bolton, Mohamed Gamal El Din
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Ultraviolet (UV) disinfection causes damage to the DNA or RNA of microorganisms, but many microorganisms can repair this damage after exposure to near-UV or visible wavelengths (310–480 nm) by a mechanism called photoreactivation. Photoreactivation is gaining more attention because it can reduce the efficiency of UV disinfection of wastewater several hours after treatment. The focus of many photoreactivation research activities on the single species has caused a considerable lack in knowledge about complex natural communities of microorganisms and their response to UV treatment. In this research, photoreactivation experiments were carried out on the influent of the UV disinfection unit at a municipal wastewater treatment plant (WWTP) in Edmonton, Alberta after exposure to a Medium-Pressure (MP) UV lamp system to evaluate the effect of environmental factors on photoreactivation of microorganisms in the actual municipal wastewater. The effect of reactivation fluence, temperature, and river water on photoreactivation of total coliforms was examined under indoor conditions. The results showed that higher effective reactivation fluence values (up to 20 J/cm2) and higher temperatures (up to 25 °C) increased the photoreactivation of total coliforms. However, increasing the percentage of river in the mixtures of the effluent and river water decreased the photoreactivation of the mixtures. The results of this research can help the municipal wastewater treatment industry to examine the environmental effects of discharging their effluents into receiving waters.Keywords: photoreactivation, reactivation fluence, river water, temperature, ultraviolet disinfection, wastewater effluent
Procedia PDF Downloads 309Resolving Conflicts of Constitutional Nature: Inside the Romanian Constitutional Court's Rulings on the Role and Competencies of the Public Authorities
Authors: Marieta Safta
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The separation and balance of state powers constitute the basis of the rule of law. Observance of this principle requires framing of public authorities within the limits of competence established by the Constitution and the law, as well as loyal cooperation between them. From this perspective, the attribution of the constitutional courts for settling legal conflicts of a constitutional nature is an important tool for correcting the tendencies of violation of these limits, as well as for identifying solutions for situations that do not find an explicit regulation in the constitutional texts. The present study analyzes the jurisprudence of the Constitutional Court of Romania in the field of legal conflicts of a constitutional nature, revealing, together with the presentation of conflict situations, the vulnerabilities of the constitutional reference texts. It is also highlighted the role of the constitutional courts in the evolution of constitutional law institutions, even in terms of defining and redefining the regime of the forms of government. The conclusion of the study, beyond the subject of legal conflicts of a constitutional nature, bears on the necessity, even more so in this matter, of the certainty of jurisdictional interpretation. This certainty cannot be achieved as long as the interpretation is not authoritative; consequently, the assurance of the effectiveness of constitutional justice constitute a key issue of the rule of law.Keywords: legal conflicts of constitutional nature, the Constitutional Court of Romania, the separation and balance of powers in the state, the effectiveness of constitutional justice
Procedia PDF Downloads 132Identifying the Barriers Facing Chinese Small and Medium-Sized Enterprises and Evaluating the Effectiveness of Public Supports
Authors: A. Yongsheng Guo, B. Obedat. Abdulazeez, C. Xiaoxian Zhu
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This study aimed to identify the barriers to the development of small and medium-sized enterprises (SMEs) in China and build a theoretical framework to evaluate the support provided by the authorities and institutions. A grounded theory approach was adopted to collect and analyze data. 32 interviews were conducted with SME managers, and open, axial and selective coding was utilized to develop themes. Based on institutional theory, grounded theory models were used to present findings. The findings showed that the main barriers in the business environment were defaulting on contracts, bureaucracy in procedures, lack of financial and legal support, limited intermediaries and channels, and poor quality of products and services. This study found that many programs were provided to support SMEs. A theoretical framework was developed to evaluate the performance of the programs from the managers’ perspective. The concepts of economy, efficiency and effectiveness were used to evaluate the perceived value of the programs. This study suggests that specialized programs are needed to suit sector-specific requirements, and creative packages are helpful in supporting SMEs' growth.Keywords: business support, public economics, public programme, SME
Procedia PDF Downloads 65Comparison of Direct and Indirect Tensile Strength of Brittle Materials and Accurate Estimate of Tensile Strength
Authors: M. Etezadi, A. Fahimifar
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In many geotechnical designs in rocks and rock masses, tensile strength of rock and rock mass is needed. The difficulties associated with performing a direct uniaxial tensile test on a rock specimen have led to a number of indirect methods for assessing the tensile strength that in the meantime the Brazilian test is more popular. Brazilian test is widely applied in rock engineering because specimens are easy to prepare, the test is easy to conduct and uniaxial compression test machines are quite common. This study compares experimental results of direct and Brazilian tensile tests carried out on two rock types and three concrete types using 39 cylindrical and 28 disc specimens. The tests are performed using Servo-Control device. The relationship between direct and indirect tensile strength of specimens is extracted using linear regression. In the following, tensile strength of direct and indirect test is evaluated using finite element analysis. The results are analyzed and effective factors on results are studied. According to the experimental results Brazilian test is shown higher tensile strength than direct test. Because of decreasing the contact surface of grains and increasing the uniformity in concrete specimens with fine aggregate (largest grain size= 6mm), higher tensile strength in direct test is shown. The experimental and numerical results of tensile strength are compared and empirical relationship witch is obtained from experimental tests is validated.Keywords: tensile strength, brittle materials, direct and indirect tensile test, numerical modeling
Procedia PDF Downloads 553Developing a Risk Rating Tool for Shopping Centres
Authors: Prandesha Govender, Chris Cloete
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Purpose: The objective of the paper is to develop a tool for the evaluation of the financial risk of a shopping center. Methodology: Important factors that indicate the success of a shopping center were identified from the available literature. Weights were allocated to these factors and a risk rating was calculated for 505 shopping centers in the largest province in South Africa by taking the factor scores, factor weights, and category weights into account. The ratings for ten randomly selected shopping centers were correlated with consumer feedback and standardized against the ECAI (External Credit Assessment Institutions) data for the same centers. The ratings were also mapped to corporates with the same risk rating to provide a better intuitive assessment of the meaning of the inherent risk of each center. Results: The proposed risk tool shows a strong linear correlation with consumer views and can be compared to expert opinions, such as that of fund managers and REITs. Interpretation of the tool was also illustrated by correlating the risk rating of selected shopping centers to the risk rating of reputable and established entities. Conclusions: The proposed Shopping Centre Risk Tool, used in conjunction with financial inputs from the relevant center, should prove useful to an investor when the desirability of investment in or expansion, renovation, or purchase of a shopping center is being considered.Keywords: risk, shopping centres, risk modelling, investment, rating tool, rating scale
Procedia PDF Downloads 120The Relation Between Oxidative Stress, Inflammation, and Neopterin in the Paraquat-Induced Lung Toxicity
Authors: M. Toygar, I. Aydin, M. Agilli, F. N. Aydin, M. Oztosun, H. Gul, E. Macit, Y. Karslioglu, T. Topal, B. Uysal, M. Honca
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Paraquat (PQ) is a well-known quaternary nitrogen herbicide. The major target organ in PQ poisoning is the lung. Reactive oxygen species (ROS) and inflammation play a crucial role in the development of PQ-induced pulmonary injury. Neopterin is synthesized in macrophage by interferon g and other cytokines. We aimed to evaluate the utility of neopterin as a diagnostic marker in PQ-induced lung toxicity. Sprague Dawley rats were randomly divided into two groups (sham and PQ), administered intraperitoneally 1 mL saline and PQ (15 mg/kg/mL) respectively. Blood samples and lungs were collected for analyses. Lung injury and fibrosis were seen in the PQ group. Serum total antioxidant capacity, lactate dehydrogenase (LDH), and lung transforming growth factor-1 (TGF-1) levels were significantly higher than the sham group (in all, p< 0.001). In addition, in the PQ group, serum neopterin and lung malondialdehyde (MDA) levels were also significantly higher than the sham group (in all, p 1/4 0.001). Serum neopterin levels were correlated with LDH activities, lung MDA, lung TGF-1 levels, and the degree of lung injury. These findings demonstrated that oxidative stress, reduction of antioxidant capacity, and inflammation play a crucial role in the PQ-induced lung injury. Elevated serum neopterin levels may be a prognostic parameter to determine extends of PQ-induced lung toxicity. Further studies may be performed to clarify the role of neopterin by different doses of PQ.Keywords: paraquat, inflammation, oxidative stress, neopterin, lung toxicity
Procedia PDF Downloads 389Awareness in the Code of Ethics for Nurse Educators among Nurse Educators, Nursing Students and Professional Nurses at the Royal Thai Army, Thailand
Authors: Wallapa Boonrod
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Thai National Education Act 1999 required all educational institutions received external quality evaluation at least once every five years. The purpose of this study was to compare the awareness in the code of ethics for nurse educators among nurse educators, professional nurses, and nursing students under The Royal Thai Army Nurse College. The sample consisted of 51 of nurse educators 200 nursing students and 340 professional nurses from Army nursing college and hospital by stratified random sampling techniques. The descriptive statistics indicated that the nurse educators, nursing students and professional nurses had different levels of awareness in the 9 roles of nurse educators: Nurse, Reliable Sacrifice, Intelligence, Giver, Nursing Skills, Teaching Responsibility, Unbiased Care, Tie to Organization, and Role Model. The code of ethics for nurse educators (CENE) measurement models from the awareness of nurse educators, professional nurses, and nursing students were well fitted with the empirical data. The CENE models from them were invariant in forms, but variant in factor loadings. Thai Army nurse educators strive to create a learning environment that nurtures the highest nursing potential and standards in their nursing students.Keywords: awareness of the code of ethics for nurse educators, nursing college and hospital under The Royal Thai Army, Thai Army nurse educators, professional nurses
Procedia PDF Downloads 455Dogmatic Instrumant in Financing Micro Project
Authors: Adel Fatima Zohra, Guendouz Abdelkader
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The solitary sector seems to appear nowadays as a third sector along the private and public ones, because of their ineptitude to take in charge the social exigency of the society regarding the lack in their local assets and the weakness of their financial institutions. The role of this sector is promoting a set of activities in the field of the charity, without aiming neither the individual profit nor a power practice. With the rise in the need of domestic resources, it is possible to count on the Zakat funding to realize some investment projects in order to develop the local society in many sectors as health, agriculture … etc. In the Islamic financial system, the Zakat is likely one of the most important instruments in financing the local development with the respect of the “Charia” rules: the amount of the Zakat is 2.5% of a wealth equivalent of each 85 gr of gold possessed since one year at least. In Algeria a fund of Zakat, was created since 2003 as an alternative to the public finding of development. This fund is a religious and social institution under the supervision of the ministry of religious affairs. This supervision covers two tasks: the first is traditional witch concern the distribution and the forwarding of the zakat to the poor people, and the second is modern concerning the financing of microcredits in the aim to enhance social and economic development. In this paper, we try to highlight the main role of the Zakat fund and its impact on the both social and economic development in Algeria.Keywords: dogmatic instrument, solidary sector, zakat fund, micro project
Procedia PDF Downloads 281Distribution of Current Emerging Contaminants in South Africa Surface and Groundwater
Authors: Jou-An Chen, Julio Castillo, Errol Duncan Cason, Gabre Kemp, Leana Esterhuizen, Angel Valverde Portal, Esta Van Heerden
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Emerging contaminants (EC) such as pharmaceutical and personal care products have been accumulating for years in water bodies all over the world. However, very little is known about the occurrences, levels, and effects of ECs in South African water resources. This study provides an initial assessment of the distribution of eight ECs (Acetaminophen, Atrazine, Terbuthlyazine, Carbamazepine, Phenyton, Sulfmethoxazole, Nevirapine and Fluconozole) in fifteen water sources from the Free State and Easter Cape provinces of South Africa. Overall, the physiochemical conditions were different in surface and groundwater samples, with concentrations of several elements such as B, Ca, Mg, Na, NO3, and TDS been statistically higher in groundwater. In contrast, ECs levels, quantified at ng/mL using the LC/MS/ESI, were much lower in groundwater samples. The ECs with higher contamination levels were Carbamazepine, Sulfmethoxazole, Nevirapine, and Terbuthlyazine, while the most widespread were Sulfmethoxazole and Fluconozole, detected in all surface and groundwater samples. Fecal and E. coli tests indicated that surface water was more contaminated than groundwater. Microbial communities, assessed using NGS, were dominated by the phyla Proteobacteria and Bacteroidetes, in both surface and groundwater. Actinobacteria, Planctomycetes, and Cyanobacteria, were more dominant in surface water, while Verrucomicrobia were overrepresented in groundwater. In conclusion, ECs contamination is closely associated with human activities (human wastes). The microbial diversity identified can suggest possible biodegradation processes.Keywords: emerging contaminants, EC, personal care products, pharmaceuticals, natural attenuation process
Procedia PDF Downloads 222Social Media as a Source of Radicalization; A Case Study of Pakistan
Authors: Manam Hanfi
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Pakistan is a victim of terrorism since 9/11 attacks. Since then it is a home for violence and extremism. One of the major reasons behind rising violence and extremism in Pakistan is radicalization. Pakistan has seen and suffered from the modification of terrorism from old to new. In new terrorism, the terrorist organizations incorporated internet to disseminate propaganda, to recruit and train people. The study focuses on the relationship between Pakistan and new terrorism and examines how the internet is being used by terrorist organizations. The study investigates radicalization through social media by terrorist organizations in Pakistan with the help of case studies. The study suggests five ways to counter radicalization, including, counter narrative on social media, content analysis of the data on the internet, curriculum and madrassa reforms, teaching peace education in the educational institutions and use of technical software such as eGLYPH to quickly remove violent data from social media. Lastly, the research attempted to contribute in counter-radicalization by combining the media dependency model and ideas for counter-radicalization. The dependency model elaborates the impact of mass media content on the audience. If media dependency is high, it will cause cognitive, affective and behavioral changes. In order to counter radicalization through social media, it is important to make cognitive, affective and behavioral changes with the help of counter-radicalization suggestions.Keywords: counter radicalization, extremism, social media, terrorism
Procedia PDF Downloads 159Variability of the Arbuscular Mycorrhizal Fungi Communities Associated with Wild Agraz Plants (Vaccinium meridionale Swartz) in the Colombian Andes
Authors: Gabriel Roveda-Hoyos, Margarita Ramirez-Gomez, Adrian Perez, Diana Paola Serralde
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The objective of this study was to determine the variability of arbuscular mycorrhizal fungi (HFMA) communities associated with wild agraz plants (Vaccinium meridionale Swartz) in the Colombian Andes. This species is one of the most promising fruits within the genus Vaccinium because of the high content of anthocyanins and antioxidants in its fruits, and like other species of the Ericaceae family, it depends on the association with HFM for its development in the natural environment. In this study, the presence of mycorrhizae in wild communities of V. meridionale was evaluated, and their relationship with the edaphic and climatic conditions of the study area was analyzed. Sampling was conducted in the rural area of the municipalities of Raquira, and Chiquinquira, Chia, and Tabio in the departments of Cundinamarca and Boyaca, Colombia. Seven sites were selected, and in each site, 5 plants were randomly selected, root and soil samples were taken from each plant in the rhizosphere zone for the quantification of colonization and the presence of spores. The samples were collected on different soils, taxonomic orders Entisols, Inceptisols, and Alfisols, located at altitudes between 2,600 and 3,000 above sea level in the Eastern Cordillera of Colombia. The physicochemical characteristics of the soil were compared with the density of spores and the percentage of presence of mycorrhizae in the roots and variables with the morphometric and physiological characteristics of the plants. Four types of mutual associations were found: arbuscular mycorrhizae, ectendomycorrhiza, ericoid mycorrhizae, and endophytic septate fungi. The main results obtained show a predominance of spores of the genera Glomus and Acaulsopora, in most of the soils analyzed. The spore density of Glomeromycete fungi in the soil varied considerably between the different sites; it was higher ( > 50 spores/g of dry soil) in soil samples with lower bulk density and higher content of organic matter; in these soils a higher cation exchange capacity was found, as well as of nitrogen, calcium, magnesium, manganese and zinc concentration. It can be concluded that Vaccinium meridionale is able to establish in a natural way, association with HFMA.Keywords: Ericaceae, Arbuscular mycorrhizae, Andes, soils, Glomus sp.
Procedia PDF Downloads 183Autism Disease Detection Using Transfer Learning Techniques: Performance Comparison between Central Processing Unit vs. Graphics Processing Unit Functions for Neural Networks
Authors: Mst Shapna Akter, Hossain Shahriar
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Neural network approaches are machine learning methods used in many domains, such as healthcare and cyber security. Neural networks are mostly known for dealing with image datasets. While training with the images, several fundamental mathematical operations are carried out in the Neural Network. The operation includes a number of algebraic and mathematical functions, including derivative, convolution, and matrix inversion and transposition. Such operations require higher processing power than is typically needed for computer usage. Central Processing Unit (CPU) is not appropriate for a large image size of the dataset as it is built with serial processing. While Graphics Processing Unit (GPU) has parallel processing capabilities and, therefore, has higher speed. This paper uses advanced Neural Network techniques such as VGG16, Resnet50, Densenet, Inceptionv3, Xception, Mobilenet, XGBOOST-VGG16, and our proposed models to compare CPU and GPU resources. A system for classifying autism disease using face images of an autistic and non-autistic child was used to compare performance during testing. We used evaluation matrices such as Accuracy, F1 score, Precision, Recall, and Execution time. It has been observed that GPU runs faster than the CPU in all tests performed. Moreover, the performance of the Neural Network models in terms of accuracy increases on GPU compared to CPU.Keywords: autism disease, neural network, CPU, GPU, transfer learning
Procedia PDF Downloads 125The Relationship between First-Day Body Temperature and Mortality in Traumatic Patients
Authors: Neda Valizadeh, Mani Mofidi, Sama Haghighi, Ali Hashemaghaee, Soudabeh Shafiee Ardestani
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Background: There are many systems and parameters to evaluate trauma patients in the emergency department. Most of these evaluations are to distinguish patients with worse conditions so that the care systems have a better prediction of condition for a better care-giving. The purpose of this study is to determine the relationship between axillary body temperature and mortality in patients hospitalized in the intensive care unit (ICU) with multiple traumas and with other clinical and para-clinical factors. Methods: All patients between 16 and 75 years old with multiple traumas who were admitted into Emergency Department then hospitalized in the ICU were included in our study. An axillary temperature in the first and the second day of admission, Glasgow cola scale (GCS), systolic blood pressure, Serum glucose levels, and white blood cell counts of all patients at the admission day were recorded and their relationship with mortality were analyzed by SPSS software with suitable statistical tests. Results: Axillary body temperatures in the first and second day were statistically lower in expired traumatic patients (p=0.001 and p<0,001 respectively). Patients with lower GCS had a significantly lower first-day temperature and a significantly higher mortality. (p=0.006 and p=0.006 respectively). Furthermore, the first-day axillary temperature was significantly lower in patients with a lower first-day systolic blood pressure (p=0.014). Conclusion: Our results showed that lower axillary body temperature in the first day is associated with higher mortality, lower GCS, and lower systolic blood pressure. Thus, this could be used as a predictor of mortality in evaluation of traumatic patients in emergency settings.Keywords: fever, trauma, mortality, emergency
Procedia PDF Downloads 381A Framework for University Social Responsibility and Sustainability: The Case of South Valley University, Egypt
Authors: Alaa Tag-Eldin Mohamed
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The environmental, cultural, social, and technological changes have led higher education institutes to question their traditional roles. Many declarations and frameworks highlight the importance of fulfilling social responsibility of higher education institutes. The study aims at developing a framework of university social responsibility and sustainability (USR&S) with focus on South Valley University (SVU) as a case study of Egyptian Universities. The study used meetings with 12 vice deans of community services and environmental affairs on social responsibility and environmental issues. The proposed framework integrates social responsibility with strategic management through the establishment and maintenance of the vision, mission, values, goals and management systems; elaboration of policies; provision of actions; evaluation of services and development of social collaboration with stakeholders to meet current and future needs of the community and environment. The framework links between different stakeholders internally and externally using communication and reporting tools. The results show that SVU integrates social responsibility and sustainability in its strategic plans. It has policies and actions however fragmented and lack of appropriate structure and budgeting. The proposed framework could be valuable for researchers and decision makers of the Egyptian Universities. The study proposed recommendations and highlighted building on the results and conducting future research.Keywords: corporate social responsibility (CSR), south valley university, sustainable university, university social responsibility and sustainability (USR&S)
Procedia PDF Downloads 352Epoxidation of Cycloalkenes Using Bead Shape Ti-Al-Beta Zeolite
Authors: Zahra Asgar Pour
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Two types of Ti-Al-containing zeolitic beads with an average diameter of 450 to 750 µm and hierarchical porosity were synthesized using a hard template method and tested as heterogeneous catalysts in the epoxidation of cycloalkenes (i.e. cyclohexene and cis-cyclooctene) with aqueous hydrogen peroxide (H₂O₂) or tert-butyl hydroperoxide(TBHP) as the oxidant agent. The first type of zeolitic beads was prepared by hydrothermal treatment of a primarygel (containing the Si, Ti, and Al precursors) in the presence of porous anion-exchange resin beads as the hard shaping template. After calcination, these beads (Ti-Al-Beta-HDT-B) consisted of both crystalline zeolite Beta and an amorphous silicate phase. The second type of zeolitic beads (Ti-Beta-PS-deAl-14.4-B) was obtained by post-synthesis dealumination of Al-containing zeolite Beta beads using 14.4 M HNO₃, followed by Ti grafting (3 wt% per gram of zeolite). The prepared materials were characterised by means of XRD, N2-physisorption, UV-vis, XRF, SEM, and TEM and tested as heterogeneous epoxidation catalysts. This post-synthetically prepared catalyst demonstrated higher activity (cyclohexene conversion of 22.7 % and epoxide selectivity of 33.5 %) after 5 h at60 °C, which emanates from the crystalline structure and higher degrees of hydrophobicity. In addition, the post-synthetically prepared beads were prone to partial Ti leaching in the presence of H₂O₂, whereas they showed to be resistant against Ti leaching using tert-butyl hydroperoxide as the oxidant agent.Keywords: epoxidation, structured catalysts, hierarchical porosity, bead-shape catalysts
Procedia PDF Downloads 111