Search results for: TB treatment regimens
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8249

Search results for: TB treatment regimens

599 Ecofriendly Synthesis of Au-Ag@AgCl Nanocomposites and Their Catalytic Activity on Multicomponent Domino Annulation-Aromatization for Quinoline Synthesis

Authors: Kanti Sapkota, Do Hyun Lee, Sung Soo Han

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Nanocomposites have been widely used in various fields such as electronics, catalysis, and in chemical, biological, biomedical and optical fields. They display broad biomedical properties like antidiabetic, anticancer, antioxidant, antimicrobial and antibacterial activities. Moreover, nanomaterials have been used for wastewater treatment. Particularly, bimetallic hybrid nanocomposites exhibit unique features as compared to their monometallic components. Hybrid nanomaterials not only afford the multifunctionality endowed by their constituents but can also show synergistic properties. In addition, these hybrid nanomaterials have noteworthy catalytic and optical properties. Notably, Au−Ag based nanoparticles can be employed in sensor and catalysis due to their characteristic composition-tunable plasmonic properties. Due to their importance and usefulness, various efforts were developed for their preparation. Generally, chemical methods have been described to synthesize such bimetallic nanocomposites. In such chemical synthesis, harmful and hazardous chemicals cause environmental contamination and increase toxicity levels. Therefore, ecologically benevolent processes for the synthesis of nanomaterials are highly desirable to diminish such environmental and safety concerns. In this regard, here we disclose a simple, cost-effective, external additive free and eco-friendly method for the synthesis of Au-Ag@AgCl nanocomposites using Nephrolepis cordifolia root extract. Au-Ag@AgCl NCs were obtained by the simultaneous reduction of cationic Ag and Au into AgCl in the presence of plant extract. The particle size of 10 to 50 nm was observed with the average diameter of 30 nm. The synthesized nanocomposite was characterized by various modern characterization techniques. For example, UV−visible spectroscopy was used to determine the optical activity of the synthesized NCs, and Fourier transform infrared (FT-IR) spectroscopy was employed to investigate the functional groups present in the biomolecules that were responsible for both reducing and capping agents during the formation of nanocomposites. Similarly, powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and energy-dispersive X-ray (EDX) spectroscopy were used to determine crystallinity, size, oxidation states, thermal stability and weight loss of the synthesized nanocomposites. As a synthetic application, the synthesized nanocomposite exhibited excellent catalytic activity for the multicomponent synthesis of biologically interesting quinoline molecules via domino annulation-aromatization reaction of aniline, arylaldehyde, and phenyl acetylene derivatives. Interestingly, the nanocatalyst was efficiently recycled for five times without substantial loss of catalytic properties.

Keywords: nanoparticles, catalysis, multicomponent, quinoline

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598 HRCT of the Chest and the Role of Artificial Intelligence in the Evaluation of Patients with COVID-19

Authors: Parisa Mansour

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Introduction: Early diagnosis of coronavirus disease (COVID-19) is extremely important to isolate and treat patients in time, thus preventing the spread of the disease, improving prognosis and reducing mortality. High-resolution computed tomography (HRCT) chest imaging and artificial intelligence (AI)-based analysis of HRCT chest images can play a central role in the treatment of patients with COVID-19. Objective: To investigate different chest HRCT findings in different stages of COVID-19 pneumonia and to evaluate the potential role of artificial intelligence in the quantitative assessment of lung parenchymal involvement in COVID-19 pneumonia. Materials and Methods: This retrospective observational study was conducted between May 1, 2020 and August 13, 2020. The study included 2169 patients with COVID-19 who underwent chest HRCT. HRCT images showed the presence and distribution of lesions such as: ground glass opacity (GGO), compaction, and any special patterns such as septal thickening, inverted halo, mark, etc. HRCT findings of the breast at different stages of the disease (early: andlt) 5 days, intermediate: 6-10 days and late stage: >10 days). A CT severity score (CTSS) was calculated based on the extent of lung involvement on HRCT, which was then correlated with clinical disease severity. Use of artificial intelligence; Analysis of CT pneumonia and quot; An algorithm was used to quantify the extent of pulmonary involvement by calculating the percentage of pulmonary opacity (PO) and gross opacity (PHO). Depending on the type of variables, statistically significant tests such as chi-square, analysis of variance (ANOVA) and post hoc tests were applied when appropriate. Results: Radiological findings were observed in HRCT chest in 1438 patients. A typical pattern of COVID-19 pneumonia, i.e., bilateral peripheral GGO with or without consolidation, was observed in 846 patients. About 294 asymptomatic patients were radiologically positive. Chest HRCT in the early stages of the disease mostly showed GGO. The late stage was indicated by such features as retinal enlargement, thickening and the presence of fibrous bands. Approximately 91.3% of cases with a CTSS = 7 were asymptomatic or clinically mild, while 81.2% of cases with a score = 15 were clinically severe. Mean PO and PHO (30.1 ± 28.0 and 8.4 ± 10.4, respectively) were significantly higher in the clinically severe categories. Conclusion: Because COVID-19 pneumonia progresses rapidly, radiologists and physicians should become familiar with typical TC chest findings to treat patients early, ultimately improving prognosis and reducing mortality. Artificial intelligence can be a valuable tool in treating patients with COVID-19.

Keywords: chest, HRCT, covid-19, artificial intelligence, chest HRCT

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597 Epidemiology, Clinical, Immune, and Molecular Profiles of Microsporidiosis and Cryptosporidiosis among HIV/AIDS patients

Authors: Roger WUMBA

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The objective of this study was to determine the prevalence of intestinal parasites, with special emphasis on microsporidia and Cryptosporidium, as well as their association with human immunodeficiency virus (HIV) symptoms, risk factors, and other digestive parasites. We also wish to determine the molecular biology definitions of the species and genotypes of microsporidia and Cryptosporidium in HIV patients. In this cross-sectional study, carried out in Kinshasa, Democratic Republic of the Congo, stool samples were collected from 242 HIV patients (87 men and 155 women) with referred symptoms and risk factors for opportunistic intestinal parasites. The analysis of feces specimen were performed using Ziehl–Neelsen stainings, real-time polymerase chain reaction (PCR), immunofluorescence indirect monoclonal antibody, nested PCR-restriction fragment length polymorphism, and PCR amplification and sequencing. Odds ratio (OR) and 95% confidence intervals were used to quantify the risk. Of the 242 HIV patients, 7.8%, 0.4%, 5.4%, 0.4%, 2%, 10.6%, and 2.8% had Enterocytozoon bieneusi, Encephalitozoon intestinalis, Cryptosporidium spp., Isospora belli, pathogenic intestinal protozoa, nonpathogenic intestinal protozoa, and helminths, respectively. We found five genotypes of E. bieneusi: two older, NIA1 and D, and three new, KIN1, KIN2, and KIN3. Only 0.4% and 1.6% had Cryptosporidium parvum and Cryptosporidium hominis, respectively. Of the patients, 36.4%, 34.3%, 31%, and 39% had asthenia, diarrhea, a CD4 count of ,100 cells/mm³, and no antiretroviral therapy (ART), respectively. The majority of those with opportunistic intestinal parasites and C. hominis, and all with C. parvum and new E. bieneusi genotypes, had diarrhea, low CD4+ counts of ,100 cells/mm³, and no ART. There was a significant association between Entamoeba coli, Kaposi sarcoma, herpes zoster, chronic diarrhea, and asthenia, and the presence of 28 cases with opportunistic intestinal parasites. Rural areas, public toilets, and exposure to farm pigs were the univariate risk factors present in the 28 cases with opportunistic intestinal parasites. In logistic regression analysis, a CD4 count of ,100 cells/mm³ (OR = 4.60; 95% CI 1.70–12.20; P = 0.002), no ART (OR = 5.00; 95% CI 1.90–13.20; P , 0.001), and exposure to surface water (OR = 2.90; 95% CI 1.01–8.40; P = 0.048) were identified as the significant and independent determinants for the presence of opportunistic intestinal parasites. E. bieneusi and Cryptosporidium are becoming more prevalent in Kinshasa, Congo. Based on the findings, we recommend epidemiology surveillance and prevention by means of hygiene, the emphasis of sensitive PCR methods, and treating opportunistic intestinal parasites that may be acquired through fecal–oral transmission, surface water, normal immunity, rural area-based person–person and animal–human nfection, and transmission of HIV. Therapy, including ART and treatment with fumagillin, is needed.

Keywords: diarrhea, enterocytozoon bieneusi, cryptosporidium hominis, cryptosporidium parvum, risk factors, africans

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596 Comparing the Effectiveness of the Crushing and Grinding Route of Comminution to That of the Mine to Mill Route in Terms of the Percentage of Middlings Present in Processed Lead-Zinc Ore Samples

Authors: Chinedu F. Anochie

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The presence of gangue particles in recovered metal concentrates has been a serious challenge to ore dressing engineers. Middlings lower the quality of concentrates, and in most cases, drastically affect the smelter terms, owing to exorbitant amounts paid by Mineral Processing industries as treatment charge. Models which encourage optimization of liberation operations have been utilized in most ore beneficiation industries to reduce the presence of locked particles in valuable concentrates. Moreover, methods such as incorporation of regrind mills, scavenger, rougher and cleaner cells, to the milling and flotation plants has been widely employed to tackle these concerns, and to optimize the grade–recovery relationship of metal concentrates. This work compared the crushing and grinding method of liberation, to the mine to mill route, by evaluating the proportion of middlings present in selectively processed complex Pb-Zn ore samples. To establish the effect of size reduction operations on the percentage of locked particles present in recovered concentrates, two similar samples of complex Pb- Zn ores were processed. Following blasting operation, the first ore sample was ground directly in a ball mill (Mine to Mill Route of Comminution), while the other sample was manually crushed, and subsequently ground in the ball mill (Crushing and Grinding Route of Comminution). The two samples were separately sieved in a mesh to obtain the desired representative particle sizes. An equal amount of each sample that would be processed in the flotation circuit was then obtained with the aid of a weighing balance. These weighed fine particles were simultaneously processed in the flotation circuit using the selective flotation technique. Sodium cyanide, Methyl isobutyl carbinol, Sodium ethyl xanthate, Copper sulphate, Sodium hydroxide, Lime and Isopropyl xanthate, were the reagents used to effect differential flotation of the two ore samples. Analysis and calculations showed that the degree of liberation obtained for the ore sample which went through the conventional crushing and grinding route of comminution, was higher than that of the directly milled run off mine (ROM) ore. Similarly, the proportion of middlings obtained from the separated galena (PbS) and sphalerite (ZnS) concentrates, were lower for the crushed and ground ore sample. A concise data which proved that the mine to mill method of size reduction is not the most ideal technique for the recovery of quality metal concentrates has been established.

Keywords: comminution, degree of liberation, middlings, mine to mill

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595 Understanding the Common Antibiotic and Heavy Metal Resistant-Bacterial Load in the Textile Industrial Effluents

Authors: Afroza Parvin, Md. Mahmudul Hasan, Md. Rokunozzaman, Papon Debnath

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The effluents of textile industries have considerable amounts of heavy metals, causing potential microbial metal loads if discharged into the environment without treatment. Aim: In this present study, both lactose and non-lactose fermenting bacterial isolates were isolated from textile industrial effluents of a specific region of Bangladesh, named Savar, to compare and understand the load of heavy metals in these microorganisms determining the effects of heavy metal resistance properties on antibiotic resistance. Methods: Five different textile industrial canals of Savar were selected, and effluent samples were collected in 2016 between June to August. Total bacterial colony (TBC) was counted for day 1 to day 5 for 10-6 dilution of samples to 10-10 dilution. All the isolates were isolated and selected using 4 differential media, and tested for the determination of minimum inhibitory concentration (MIC) of heavy metals and antibiotic susceptibility test with plate assay method and modified Kirby-Bauer disc diffusion method, respectively. To detect the combined effect of heavy metals and antibiotics, a binary exposure experiment was performed, and to understand the plasmid profiling plasmid DNA was extracted by alkaline lysis method of some selective isolates. Results: Most of the cases, the colony forming units (CFU) per plate for 50 ul diluted sample were uncountable at 10-6 dilution, however, countable for 10-10 dilution and it didn’t vary much from canal to canal. A total of 50 Shigella, 50 Salmonella, and 100 E.coli (Escherichia coli) like bacterial isolates were selected for this study where the MIC was less than or equal to 0.6 mM for 100% Shigella and Salmonella like isolates, however, only 3% E. coli like isolates had the same MIC for nickel (Ni). The MIC for chromium (Cr) was less than or equal to 2.0 mM for 16% Shigella, 20% Salmonella, and 17% E. coli like isolates. Around 60% of both Shigella and Salmonella, but only 20% of E.coli like isolates had a MIC of less than or equal to 1.2 mM for lead (Pb). The most prevalent resistant pattern for azithromycin (AZM) for Shigella and Salmonella like isolates was found 38% and 48%, respectively; however, for E.coli like isolates, the highest pattern (36%) was found for sulfamethoxazole-trimethoprim (SXT). In the binary exposure experiment, antibiotic zone of inhibition was mostly increased in the presence of heavy metals for all types of isolates. The highest sized plasmid was found 21 Kb and 14 Kb for lactose and non-lactose fermenting isolates, respectively. Conclusion: Microbial resistance to antibiotics and metal ions, has potential health hazards because these traits are generally associated with transmissible plasmids. Microorganisms resistant to antibiotics and tolerant to metals appear as a result of exposure to metal-contaminated environments.

Keywords: antibiotics, effluents, heavy metals, minimum inhibitory concentration, resistance

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594 Assessment of Physical Activity and Sun Exposure of Saudi Patients with Type 2 Diabetes Mellitus in Ramadan and Non-Ramadan Periods

Authors: Abdullah S. Alghamdi, Khaled Alghamdi, Richard O. Jenkins, Parvez I. Haris

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Background: Physical activity is an important factor in the treatment and prevention of type 2 diabetes mellitus (T2DM). Reduction in HbA1c level, an important diabetes biomarker, was reported in patients who increased their daily physical activity. Although the ambient temperature was reported to be positively correlated to a negative impact on health and increase the incidences of diabetes, the exposure to bright sunlight was recently found to be associated with enhanced insulin sensitivity and improved beta-cell function. How Ramadan alters physical activity, and especially sunlight exposure, has not been adequately investigated. Aim: This study aimed to assess the physical activity and sun exposure of Saudis with T2DM over different periods (before, during, and after Ramadan) and related this to HbA1c levels. Methods: This study recruited 82 Saudis with T2DM, who chose to fast during Ramadan, from the Endocrine and Diabetic Centre of Al Iman General Hospital, Riyadh, Saudi Arabia. Ethical approvals for this study were obtained from De Montfort University and Saudi Ministry of Health. Physical activity and sun exposure were assessed by a self-administered questionnaire. Physical activity was estimated using the International Physical Activity Questionnaire (IPAQ), while the sun exposure was assessed by asking the patients about their hours per week of direct exposure to the sun, and daily hours spent outdoors. Blood samples were collected in each period for measuring HbA1c. Results: Low physical activity was observed in more than 60% of the patients, with no significant changes between periods. There were no significant variances between periods in the daily hours spent outdoors and the total number of weekly hours of direct exposure to the sun. The majority of patients reported only few hours of exposure to the sun (1h or less per week) and time spent outdoors (1h or less per day). The mean HbA1c significantly changed between periods (P = 0.001), with lowest level during Ramadan. There were significant differences in the mean HbA1c between the groups for the level of physical activity (P < 0.001), with significant lower mean HbA1c in the higher-level group. There were no significant variances in the mean of HbA1c between the groups for the daily hours spent outdoors. The mean HbA1c of the patients, who reported never in their total weekly hours of exposure to the sun, was significantly lower than the mean HbA1c of those who reported 1 hour or less (P = 0.001). Conclusion: Physical inactivity was prevalent among the study population with very little exposure to the sun or time spent outdoors. Higher level of physical activity was associated with lower mean HbA1c levels. Encouraging T2DM patients to achieve the recommended levels of physical activity may help them to obtain greater benefits of Ramadan fasting, such as reducing their HbA1c levels. The impact of low direct exposure to the sun and the time spent outdoors needs to be further investigated in both healthy and diabetic patients.

Keywords: diabetes, fasting, physical activity, sunlight, Ramadan

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593 Production of Ferroboron by SHS-Metallurgy from Iron-Containing Rolled Production Wastes for Alloying of Cast Iron

Authors: G. Zakharov, Z. Aslamazashvili, M. Chikhradze, D. Kvaskhvadze, N. Khidasheli, S. Gvazava

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Traditional technologies for processing iron-containing industrial waste, including steel-rolling production, are associated with significant energy costs, the long duration of processes, and the need to use complex and expensive equipment. Waste generated during the industrial process negatively affects the environment, but at the same time, it is a valuable raw material and can be used to produce new marketable products. The study of the effectiveness of self-propagating high-temperature synthesis (SHS) methods, which are characterized by the simplicity of the necessary equipment, the purity of the final product, and the high processing speed, is under the wide scientific and practical interest to solve the set problem. The work presents technological aspects of the production of Ferro boron by the method of SHS - metallurgy from iron-containing wastes of rolled production for alloying of cast iron and results of the effect of alloying element on the degree of boron assimilation with liquid cast iron. Features of Fe-B system combustion have been investigated, and the main parameters to control the phase composition of synthesis products have been experimentally established. Effect of overloads on patterns of cast ligatures formation and mechanisms structure formation of SHS products was studied. It has been shown that an increase in the content of hematite Fe₂O₃ in iron-containing waste leads to an increase in the content of phase FeB and, accordingly, the amount of boron in the ligature. Boron content in ligature is within 3-14%, and the phase composition of obtained ligatures consists of Fe₂B and FeB phases. Depending on the initial composition of the wastes, the yield of the end product reaches 91 - 94%, and the extraction of boron is 70 - 88%. Combustion processes of high exothermic mixtures allow to obtain a wide range of boron-containing ligatures from industrial wastes. In view of the relatively low melting point of the obtained SHS-ligature, the positive dynamics of boron absorption by liquid iron is established. According to the obtained data, the degree of absorption of the ligature by alloying gray cast iron at 1450°C is 80-85%. When combined with the treatment of liquid cast iron with magnesium, followed by alloying with the developed ligature, boron losses are reduced by 5-7%. At that, uniform distribution of boron micro-additives in the volume of treated liquid metal is provided. Acknowledgment: This work was supported by Shota Rustaveli Georgian National Science Foundation of Georgia (SRGNSFG) under the GENIE project (grant number № CARYS-19-802).

Keywords: self-propagating high-temperature synthesis, cast iron, industrial waste, ductile iron, structure formation

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592 Factors Influencing Family Resilience and Quality of Life in Pediatric Cancer Patients and Their Caregivers: A Cluster Analysis

Authors: Li Wang, Dan Shu, Shiguang Pang, Lixiu Wang, Bing Xiang Yang, Qian Liu

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Background: Cancer is one of the most severe diseases in childhood; long-term treatment and its side effects significantly impact the patient's physical, psychological, social functioning and quality of life while also placing substantial physical and psychological burdens on caregivers and families. Family resilience is crucial for children with cancer, helping them cope better with the disease and supporting the family in facing challenges together. As a family-level variable, family resilience requires information from multiple family members. However, to our best knowledge, there is currently no research investigating family resilience from both the perspectives of pediatric cancer patients and their caregivers. Therefore, this study aims to investigate the family resilience and quality of life of pediatric cancer patients from a patient–caregiver dyadic perspective. Methods: A total of 149 dyads of patients diagnosed with pediatric cancer patients and their principal caregivers were recruited from oncology departments of 4 tertiary hospitals in Wuhan and Taiyuan, China. All participants completed questionnaires that identified their demographic and clinical characteristics as well as assessed their family resilience and quality of life for both the patients and their caregivers. K-means cluster analysis was used to identify different clusters of family resilience based on the reports from patients and caregivers. Multivariate logistic regression and linear regression are used to analyze the factors influencing family resilience and quality of life, as well as the relationship between the two. Results: Three clusters of family resilience were identified: a cluster of high family resilience (HR), a cluster of low family resilience (LR), and a cluster of discrepant family resilience (DR). Most (67.1%) families fell into the cluster with low resilience. Characteristics such as the types of caregivers perceived social support of the patient were different among the three clusters. Compared to the LR group, families where the mother is the caregiver and where the patient has high social support are more likely to be assigned to the HR. The quality of life for caregivers was consistently highest in the HR cluster and lowest in the LR cluster. The patient's quality of life is not related to family resilience. In the linear regression analysis of the patient's quality of life, patients who are the first-born have higher quality of life, while those living with their parents have lower quality of life. The participants' characteristics were not associated with the quality of life for caregivers. Conclusions: In most families, family resilience was low. Families with maternal caregivers and patients receiving high levels of social support are more inclined to be higher levels of family resilience. Family resilience was linked to the quality of life of caregivers of pediatric cancer patients. The clinical implications of this findings suggest that healthcare and social support organizations should prioritize and support the participation of mothers in caregiving responsibilities. Furthermore, they should assist families in accessing social support to enhance family resilience. This study also emphasizes the importance of promoting family resilience for enhancing family health and happiness, as well as improving the quality of life for caregivers.

Keywords: pediatric cancer, cluster analysis, family resilience, quality of life

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591 Autophagy in the Midgut Epithelium of Spodoptera exigua Hübner (Lepidoptera: Noctuidae) Larvae Exposed to Various Cadmium Concentration - 6-Generational Exposure

Authors: Magdalena Maria Rost-Roszkowska, Alina Chachulska-Żymełka, Monika Tarnawska, Maria Augustyniak, Alina Kafel, Agnieszka Babczyńska

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Autophagy is a form of cell remodeling in which an internalization of organelles into vacuoles that are called autophagosomes occur. Autophagosomes are the targets of lysosomes, thus causing digestion of cytoplasmic components. Eventually, it can lead to the death of the entire cell. However, in response to several stress factors, e.g., starvation, heavy metals (e.g., cadmium) autophagy can also act as a pro-survival factor, protecting the cell against its death. The main aim of our studies was to check if the process of autophagy, which could appear in the midgut epithelium after Cd treatment, can be fixed during the following generations of insects. As a model animal, we chose the beet armyworm Spodoptera exigua Hübner (Lepidoptera: Noctuidae), a well-known polyphagous pest of many vegetable crops. We analyzed specimens at final larval stage (5th larval stage), due to its hyperfagy, resulting in great amount of cadmium assimilate. The culture consisted of two strains: a control strain (K) fed a standard diet, and a cadmium strain (Cd), fed on standard diet supplemented with cadmium (44 mg Cd per kg of dry weight of food) for 146 generations, both strains. In addition, the control insects were transferred to the Cd supplemented diet (5 mg Cd per kg of dry weight of food, 10 mg Cd per kg of dry weight of food, 20 mg Cd per kg of dry weight of food, 44 mg Cd per kg of dry weight of food). Therefore, we obtained Cd1, Cd2, Cd3 and KCd experimental groups. Autophagy has been examined using transmission electron microscope. During this process, degenerated organelles were surrounded by a membranous phagophore and enclosed in an autophagosome. Eventually, after the autophagosome fused with a lysosome, an autolysosome was formed and the process of the digestion of organelles began. During the 1st year of the experiment, we analyzed specimens of 6 generations in all the lines. The intensity of autophagy depends significantly on the generation, tissue and cadmium concentration in the insect rearing medium. In the Ist, IInd, IIIrd, IVth, Vth and VIth generation the intensity of autophagy in the midguts from cadmium-exposed strains decreased gradually according to the following order of strains: Cd1, Cd2, Cd3 and KCd. The higher amount of cells with autophagy was observed in Cd1 and Cd2. However, it was still higher than the percentage of cells with autophagy in the same tissues of the insects from the control and multigenerational cadmium strain. This may indicate that during 6-generational exposure to various Cd concentration, a preserved tolerance to cadmium was not maintained. The study has been financed by the National Science Centre Poland, grant no 2016/21/B/NZ8/00831.

Keywords: autophagy, cell death, digestive system, ultrastructure

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590 Bacterial Decontamination of Nurses' White Coats by Application of Antimicrobial Finish

Authors: Priyanka Gupta, Nilanjana Bairagi, Deepti Gupta

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New pathogenic strains of microbes are continually emerging and resistance of bacteria to antibiotics is growing. Hospitals in India have a high burden of infections in their intensive care units and general wards. Rising incidence of hospital infections is a matter of great concern in India. This growth is often attributed to the absence of effective infection control strategies in healthcare facilities. Government, therefore, is looking for cost effective strategies that are effective against HAIs. One possible method is by application of an antimicrobial finish on the uniform. But there are limited studies to show the effect of antimicrobial activity of antimicrobial finish treated nurses’ uniforms in a real hospital set up. This paper proposes a prospective non-destructive sampling technique, based on the use of a detachable fabric patch, to assess the effectiveness of silver based antimicrobial agent across five wards in a tertiary care government hospital in Delhi, India. Fabrics like polyester and polyester cotton blend fabric which are more prevalent for making coats were selected for the study. Polyester and polyester cotton blend fabric was treated with silver based antimicrobial (AM) finish. At the beginning of shift, a composite patch of untreated and treated fabric respectively was stitched on the abdominal region on the left and right side of the washed white coat of participating nurse. At the end of the shift, the patch was removed and taken for bacterial sampling on Brain Heart Infusion (BHI) plates. Microbial contamination on polyester and blend fabrics after 6 hours shift was compared in Brain Heart Infusion broth (BHI). All patches treated with silver based antimicrobial agent showed decreased bacterial counts. Percent reduction in the bacterial colonies after the antimicrobial treatment in both fabrics was 81.0 %. Antimicrobial finish was equally effective in reducing microbial adhesion on both fabric types. White coats of nurses become progressively contaminated during clinical care. Type of fabric used to make the coat can affect the extent of contamination which is higher on polyester cotton blend as compared to 100% polyester. The study highlights the importance of silver based antimicrobial finish in the area of uniform hygiene. Bacterial load can be reduced by using antimicrobial finish on hospital uniforms. Hospital staff uniforms endowed with antimicrobial properties may be of great help in reducing the occurrence and spread of infections.

Keywords: antimicrobial finish, bacteria, infection control, silver, white coat

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589 Pickering Dry Emulsion System for Dissolution Enhancement of Poorly Water Soluble Drug (Fenofibrate)

Authors: Nitin Jadhav, Pradeep R. Vavia

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Poor water soluble drugs are difficult to promote for oral drug delivery as they demonstrate poor and variable bioavailability because of its poor solubility and dissolution in GIT fluid. Nowadays lipid based formulations especially self microemulsifying drug delivery system (SMEDDS) is found as the most effective technique. With all the impressive advantages, the need of high amount of surfactant (50% - 80%) is the major drawback of SMEDDS. High concentration of synthetic surfactant is known for irritation in GIT and also interference with the function of intestinal transporters causes changes in drug absorption. Surfactant may also reduce drug activity and subsequently bioavailability due to the enhanced entrapment of drug in micelles. In chronic treatment these issues are very conspicuous due to the long exposure. In addition the liquid self microemulsifying system also suffers from stability issues. Recently one novel approach of solid stabilized micro and nano emulsion (Pickering emulsion) has very admirable properties such as high stability, absence or very less concentration of surfactant and easily converts into the dry form. So here we are exploring pickering dry emulsion system for dissolution enhancement of anti-lipemic, extremely poorly water soluble drug (Fenofibrate). Oil moiety for emulsion preparation was selected mainly on the basis of higher solubility of drug. Captex 300 was showed higher solubility for fenofibrate, hence selected as oil for emulsion. With Silica (solid stabilizer); Span 20 was selected to improve the wetting property of it. Emulsion formed by Silica and Span20 as stabilizer at the ratio 2.5:1 (silica: span 20) was found very stable at the particle size 410 nm. The prepared emulsion was further preceded for spray drying and formed microcapsule evaluated for in-vitro dissolution study, in-vivo pharmacodynamic study and characterized for DSC, XRD, FTIR, SEM, optical microscopy etc. The in vitro study exhibits significant dissolution enhancement of formulation (85 % in 45 minutes) as compared to plain drug (14 % in 45 minutes). In-vivo study (Triton based hyperlipidaemia model) exhibits significant reduction in triglyceride and cholesterol with formulation as compared to plain drug indicating increasing in fenofibrate bioavailability. DSC and XRD study exhibit loss of crystallinity of drug in microcapsule form. FTIR study exhibit chemical stability of fenofibrate. SEM and optical microscopy study exhibit spherical structure of globule coated with solid particles.

Keywords: captex 300, fenofibrate, pickering dry emulsion, silica, span20, stability, surfactant

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588 Transformations of River Zones in Hanoi, Vietnam: Problems of Urban Drainage and Environmental Pollution

Authors: Phong Le Ha

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In many cities the entire world, the relationship between cities and rivers is always considered as a fundament of urban history research because of their profound interactions. This kind of relationship makes the river zones become extremely sensitive in many aspects. One of the most important aspect is their roles in the drainage of cities. In this paper we will examine an extraordinary case of Hanoi, the capital of Vietnam and Red river zones. This river has contradictory impacts to this city: It is considered as a source of life of the inhabitants who live along its two banks, however, the risk of inundation caused by the complicated hydrology system of this river is always a real threat to the cities that it flows through. Morphologically, Red river was connected to the inner rivers system that made Hanoi a complete form of a river city. This structure combined with the topography of Hanoi helps this city to assure a stable drainage system in which the river zones in the north of Hanoi play some extreme important roles. Nevertheless, in the late 20 years, Hanoi's strong urbanization and the instability of Red river's complicated hydrology make the very remarkable transformations in the relationship river-city and in the river zones: The connection between the river and the city declines; the system of inner lakes are progressively replaced by habitat land; in the river zones, the infrastructure system can't adapt to the transformations of the new quarters which have the origin of the agricultural villages. These changes bring out many chances for the urban development, but also many risks and problems, particularly in the environment and technical sides. Among these, pluvial and used water evacuation is one of the most severe problems. The disappear of inner-city lakes, the high dike and the topographical changes of Hanoi blow up the risk of inundation of this city. In consequences, the riverine zones, particularly in the north of Hanoi, where the two most important water evacuation rivers of Hanoi meet each other, are burdened with the drainage pressure. The unique water treatment plant in this zone seems to be overcharged in receiving each day about 40000m3 of used water (not include pluvial water). This kind of problem leads also to another risk related to the environmental pollution (water pollution and air pollution). So, in order to better understand the situation and to propose the solutions to resolve the problems, an interdisciplinary research covering many different fields such urban planning, architecture, geography, and especially drainage and environment has been carried out. In general, this paper will analyze an important part of the research : the process of urban transformation of Hanoi (changes in urban morphology, infrastructure system, evolution of the dike system, ...) and the hydrological changes of Red river which cause the drainage and environmental problems. The conclusions of these analyses will be the solid base of the following researches focusing on the solutions of a sustainable development.

Keywords: drainage, environment, Hanoi, infrastructure, red rivers, urbanization

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587 A Comparison and Discussion of Modern Anaesthetic Techniques in Elective Lower Limb Arthroplasties

Authors: P. T. Collett, M. Kershaw

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Introduction: The discussion regarding which method of anesthesia provides better results for lower limb arthroplasty is a continuing debate. Multiple meta-analysis has been performed with no clear consensus. The current recommendation is to use neuraxial anesthesia for lower limb arthroplasty; however, the evidence to support this decision is weak. The Enhanced Recovery After Surgery (ERAS) society has recommended, either technique can be used as part of a multimodal anesthetic regimen. A local study was performed to see if the current anesthetic practice correlates with the current recommendations and to evaluate the efficacy of the different techniques utilized. Method: 90 patients who underwent total hip or total knee replacements at Nevill Hall Hospital between February 2019 to July 2019 were reviewed. Data collected included the anesthetic technique, day one opiate use, pain score, and length of stay. The data was collected from anesthetic charts, and the pain team follows up forms. Analysis: The average of patients undergoing lower limb arthroplasty was 70. Of those 83% (n=75) received a spinal anaesthetic and 17% (n=15) received a general anaesthetic. For patients undergoing knee replacement under general anesthetic the average day, one pain score was 2.29 and 1.94 if a spinal anesthetic was performed. For hip replacements, the scores were 1.87 and 1.8, respectively. There was no statistical significance between these scores. Day 1 opiate usage was significantly higher in knee replacement patients who were given a general anesthetic (45.7mg IV morphine equivalent) vs. those who were operated on under spinal anesthetic (19.7mg). This difference was not noticeable in hip replacement patients. There was no significant difference in length of stay between the two anesthetic techniques. Discussion: There was no significant difference in the day one pain score between the patients who received a general or spinal anesthetic for either knee or hip replacements. The higher pain scores in the knee replacement group overall are consistent with this being a more painful procedure. This is a small patient population, which means any difference between the two groups is unlikely to be representative of a larger population. The pain scale has 4 points, which means it is difficult to identify a significant difference between pain scores. Conclusion: There is currently little standardization between the different anesthetic approaches utilized in Nevill Hall Hospital. This is likely due to the lack of adherence to a standardized anesthetic regimen. In accordance with ERAS recommends a standard anesthetic protocol is a core component. The results of this study and the guidance from the ERAS society will support the implementation of a new health board wide ERAS protocol.

Keywords: anaesthesia, orthopaedics, intensive care, patient centered decision making, treatment escalation

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586 Household Perspectives and Resistance to Preventive Relocation in Flood Prone Areas: A Case Study in the Polwatta River Basin, Southern Sri Lanka

Authors: Ishara Madusanka, So Morikawa

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Natural disasters, particularly floods, pose severe challenges globally, affecting both developed and developing countries. In many regions, especially Asia, riverine floods are prevalent and devastating. Integrated flood management incorporates structural and non-structural measures, with preventive relocation emerging as a cost-effective and proactive strategy for areas repeatedly impacted by severe flooding. However, preventive relocation is often hindered by economic, psychological, social, and institutional barriers. This study investigates the factors influencing resistance to preventive relocation and evaluates the role of flood risk information in shaping relocation decisions through risk perception. A conceptual model was developed, incorporating variables such as Flood Risk Information (FRI), Place Attachment (PA), Good Living Conditions (GLC), and Adaptation to Flooding (ATF), with Flood Risk Perception (FRP) serving as a mediating variable. The research was conducted in Welipitiya in the Polwatta river basin, Matara district, Sri Lanka, a region experiencing recurrent flood damage. For this study, an experimental design involving a structured questionnaire survey was utilized, with 185 households participating. The treatment group received flood risk information, including flood risk maps and historical data, while the control group did not. Data were collected in 2023 and analyzed using independent sample t-tests and Partial Least Squares Structural Equation Modeling (PLS-SEM). PLS-SEM was chosen for its ability to model latent variables, handle complex relationships, and suitability for exploratory research. Multi-group Analysis (MGA) assessed variations across different flood risk areas. Findings indicate that flood risk information had a limited impact on flood risk perception and relocation decisions, though its effect was significant in specific high-risk areas. Place attachment was a significant factor influencing relocation decisions across the sample. One potential reason for the limited impact of flood risk information on relocation decisions could be the lack of specificity in the information provided. The results suggest that while flood risk information alone may not significantly influence relocation decisions, it is crucial in specific contexts. Future studies and practitioners should focus on providing more detailed risk information and addressing psychological factors like place attachments to enhance preventive relocation efforts.

Keywords: flood risk communication, flood risk perception, place attachment, preventive relocation, structural equation modeling

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585 Telemedicine Services in Ophthalmology: A Review of Studies

Authors: Nasim Hashemi, Abbas Sheikhtaheri

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Telemedicine is the use of telecommunication and information technologies to provide health care services that would often not be consistently available in distant rural communities to people at these remote areas. Teleophthalmology is a branch of telemedicine that delivers eye care through digital medical equipment and telecommunications technology. Thus, teleophthalmology can overcome geographical barriers and improve quality, access, and affordability of eye health care services. Since teleophthalmology has been widespread applied in recent years, the aim of this study was to determine the different applications of teleophthalmology in the world. To this end, three bibliographic databases (Medline, ScienceDirect, Scopus) were comprehensively searched with these keywords: eye care, eye health care, primary eye care, diagnosis, detection, and screening of different eye diseases in conjunction with telemedicine, telehealth, teleophthalmology, e-services, and information technology. All types of papers were included in the study with no time restriction. We conducted the search strategies until 2015. Finally 70 articles were surveyed. We classified the results based on the’type of eye problems covered’ and ‘the type of telemedicine services’. Based on the review, from the ‘perspective of health care levels’, there are three level for eye health care as primary, secondary and tertiary eye care. From the ‘perspective of eye care services’, the main application of teleophthalmology in primary eye care was related to the diagnosis of different eye diseases such as diabetic retinopathy, macular edema, strabismus and aged related macular degeneration. The main application of teleophthalmology in secondary and tertiary eye care was related to the screening of eye problems i.e. diabetic retinopathy, astigmatism, glaucoma screening. Teleconsultation between health care providers and ophthalmologists and also education and training sessions for patients were other types of teleophthalmology in world. Real time, store–forward and hybrid methods were the main forms of the communication from the perspective of ‘teleophthalmology mode’ which is used based on IT infrastructure between sending and receiving centers. In aspect of specialists, early detection of serious aged-related ophthalmic disease in population, screening of eye disease processes, consultation in an emergency cases and comprehensive eye examination were the most important benefits of teleophthalmology. Cost-effectiveness of teleophthalmology projects resulted from reducing transportation and accommodation cost, access to affordable eye care services and receiving specialist opinions were also the main advantages of teleophthalmology for patients. Teleophthalmology brings valuable secondary and tertiary care to remote areas. So, applying teleophthalmology for detection, treatment and screening purposes and expanding its use in new applications such as eye surgery will be a key tool to promote public health and integrating eye care to primary health care.

Keywords: applications, telehealth, telemedicine, teleophthalmology

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584 Methylphenidate Use by Canadian Children and Adolescents and the Associated Adverse Reactions

Authors: Ming-Dong Wang, Abigail F. Ruby, Michelle E. Ross

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Methylphenidate is a first-line treatment drug for attention deficit hyperactivity disorder (ADHD), a common mental health disorder in children and adolescents. Over the last several decades, the rate of children and adolescents using ADHD medication has been increasing in many countries. A recent study found that the prevalence of ADHD medication use among children aged 3-18 years increased in 13 different world regions between 2001 and 2015, where the absolute increase ranged from 0.02 to 0.26% per year. The goal of this study was to examine the use of methylphenidate in Canadian children and its associated adverse reactions. Methylphenidate use information among young Canadians aged 0-14 years was extracted from IQVIA data on prescriptions dispensed by pharmacies between April 2014 and June 2020. The adverse reaction information associated with methylphenidate use was extracted from the Canada Vigilance database for the same time period. Methylphenidate use trends were analyzed based on sex, age group (0-4 years, 5-9 years, and 10-14 years), and geographical location (province). The common classes of adverse reactions associated with methylphenidate use were sorted, and the relative risks associated with methylphenidate use as compared with two second-line amphetamine medications for ADHD were estimated. This study revealed that among Canadians aged 0-14 years, every 100 people used about 25 prescriptions (or 23,000 mg) of methylphenidate per year during the study period, and the use increased with time. Boys used almost three times more methylphenidate than girls. The amount of drug used was inversely associated with age: Canadians aged 10-14 years used nearly three times as many drugs compared to those aged 5-9 years. Seasonal methylphenidate use patterns were apparent among young Canadians, but the seasonal trends differed among the three age groups. Methylphenidate use varied from region to region, and the highest methylphenidate use was observed in Quebec, where the use of methylphenidate was at least double that of any other province. During the study period, Health Canada received 304 adverse reaction reports associated with the use of methylphenidate for Canadians aged 0-14 years. The number of adverse reaction reports received for boys was 3.5 times higher than that for girls. The three most common adverse reaction classes were psychiatric disorders, nervous system disorders and injury, poisoning procedural complications. The number one commonly reported adverse reaction for boys was aggression (11.2%), while for girls, it was a tremor (9.6%). The safety profile in terms of adverse reaction classes associated with methylphenidate use was similar to that of the selected control products. Methylphenidate is a commonly used pharmaceutical product in young Canadians, particularly in the province of Quebec. Boys used approximately three times more of this product as compared to girls. Future investigation is needed to determine what factors are associated with the observed geographic variations in Canada.

Keywords: adverse reaction risk, methylphenidate, prescription trend, use variation

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583 Denial among Women Living with Cancer: An Exploratory Study to Understand the Consequences of Cancer and the Denial Mechanism

Authors: Judith Partouche-Sebban, Saeedeh Rezaee Vessal

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Because of the rising number of new cases of cancer, especially among women, it is more than essential to better understand how women experience cancer in order to bring them adapted to support and care and enhance their well-being and patient experience. Cancer stands for a traumatic experience in which the diagnosis, its medical treatments, and the related side effects lead to deep physical and psychological changes that may arouse considerable stress and anxiety. In order to reduce these negative emotions, women tend to use various defense mechanisms, among which denial has been defined as the most frequent mechanism used by breast cancer patients. This study aims to better understand the consequences of the experience of cancer and their link with the adoption of a denial strategy. The empirical research was done among female cancer survivors in France. Since the topic of this study is relatively unexplored, a qualitative methodology and open-ended interviews were employed. In total, 25 semi-directive interviews were conducted with a female with different cancers, different stages of treatment, and different ages. A systematic inductive method was performed to analyze data. The content analysis enabled to highlight three different denial-related behaviors among women with cancer, which serve a self-protective function. First, women who expressed high levels of anxiety confessed they tended to completely deny the existence of their cancer immediately after the diagnosis of their illness. These women mainly exhibit many fears and a deep distrust toward the medical context and professionals. This coping mechanism is defined by the patient as being unconscious. Second, other women deliberately decided to deny partial information about their cancer, whether this information is related to the stages of the illness, the emotional consequences, or the behavioral consequences of the illness. These women use this strategy as a way to avoid the reality of the illness and its impact on the different aspects of their life as if cancer does not exist. Third, some women tend to reinterpret and give meaning to their cancer as a way to reduce its impact on their life. To this end, they may use magical thinking or positive reframing, or reinterpretation. Because denial may lead to delays in medical treatments, this topic deserves a deep investigation, especially in the context of oncology. As denial is defined as a specific defense mechanism, this study contributes to the existing literature in service marketing which focuses on emotions and emotional regulation in healthcare services which is a crucial issue. Moreover, this study has several managerial implications for healthcare professionals who interact with patients in order to implement better care and support for the patients.

Keywords: cancer, coping mechanisms, denial, healthcare services

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582 Effects of Oxytocin on Neural Response to Facial Emotion Recognition in Schizophrenia

Authors: Avyarthana Dey, Naren P. Rao, Arpitha Jacob, Chaitra V. Hiremath, Shivarama Varambally, Ganesan Venkatasubramanian, Rose Dawn Bharath, Bangalore N. Gangadhar

Abstract:

Objective: Impaired facial emotion recognition is widely reported in schizophrenia. Neuropeptide oxytocin is known to modulate brain regions involved in facial emotion recognition, namely amygdala, in healthy volunteers. However, its effect on facial emotion recognition deficits seen in schizophrenia is not well explored. In this study, we examined the effect of intranasal OXT on processing facial emotions and its neural correlates in patients with schizophrenia. Method: 12 male patients (age= 31.08±7.61 years, education= 14.50±2.20 years) participated in this single-blind, counterbalanced functional magnetic resonance imaging (fMRI) study. All participants underwent three fMRI scans; one at baseline, one each after single dose 24IU intranasal OXT and intranasal placebo. The order of administration of OXT and placebo were counterbalanced and subject was blind to the drug administered. Participants performed a facial emotion recognition task presented in a block design with six alternating blocks of faces and shapes. The faces depicted happy, angry or fearful emotions. The images were preprocessed and analyzed using SPM 12. First level contrasts comparing recognition of emotions and shapes were modelled at individual subject level. A group level analysis was performed using the contrasts generated at the first level to compare the effects of intranasal OXT and placebo. The results were thresholded at uncorrected p < 0.001 with a cluster size of 6 voxels. Neuropeptide oxytocin is known to modulate brain regions involved in facial emotion recognition, namely amygdala, in healthy volunteers. Results: Compared to placebo, intranasal OXT attenuated activity in inferior temporal, fusiform and parahippocampal gyri (BA 20), premotor cortex (BA 6), middle frontal gyrus (BA 10) and anterior cingulate gyrus (BA 24) and enhanced activity in the middle occipital gyrus (BA 18), inferior occipital gyrus (BA 19), and superior temporal gyrus (BA 22). There were no significant differences between the conditions on the accuracy scores of emotion recognition between baseline (77.3±18.38), oxytocin (82.63 ± 10.92) or Placebo (76.62 ± 22.67). Conclusion: Our results provide further evidence to the modulatory effect of oxytocin in patients with schizophrenia. Single dose oxytocin resulted in significant changes in activity of brain regions involved in emotion processing. Future studies need to examine the effectiveness of long-term treatment with OXT for emotion recognition deficits in patients with schizophrenia.

Keywords: recognition, functional connectivity, oxytocin, schizophrenia, social cognition

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581 Comparison of the Toxicity of Silver and Gold Nanoparticles in Murine Fibroblasts

Authors: Šárka Hradilová, Aleš Panáček, Radek Zbořil

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Nanotechnologies are considered the most promising fields with high added value, brings new possibilities in various sectors from industry to medicine. With the growing of interest in nanomaterials and their applications, increasing nanoparticle production leads to increased exposure of people and environment with ‘human made’ nanoparticles. Nanoparticles (NPs) are clusters of atoms in the size range of 1–100 nm. Metal nanoparticles represent one of the most important and frequently used types of NPs due to their unique physical, chemical and biological properties, which significantly differ from those of bulk material. Biological properties including toxicity of metal nanoparticles are generally determined by their size, size distribution, shape, surface area, surface charge, surface chemistry, stability in the environment and ability to release metal ions. Therefore, the biological behavior of NPs and their possible adverse effect cannot be derived from the bulk form of material because nanoparticles show unique properties and interactions with biological systems just due to their nanodimensions. Silver and gold NPs are intensively studied and used. Both can be used for instance in surface enhanced Raman spectroscopy, a considerable number of applications of silver NPs is associated with antibacterial effects, while gold NPs are associated with cancer treatment and bio imaging. Antibacterial effects of silver ions are known for centuries. Silver ions and silver-based compounds are highly toxic to microorganisms. Toxic properties of silver NPs are intensively studied, but the mechanism of cytoxicity is not fully understood. While silver NPs are considered toxic, gold NPs are referred to as toxic but also innocuous for eukaryotic cells. Therefore, gold NPs are used in various biological applications without a risk of cell damaging, even when we want to suppress the growth of cancer cells. Thus, gold NPs are toxic or harmless. Because most studies comparing particles of various sizes prepared in various ways, and testing is performed on different cell lines, it is very difficult to generalize. The novelty and significance of our research is focused to the complex biological effects of silver and gold NPs prepared by the same method, have the same parameters and the same stabilizer. That is why we can compare the biological effects of pure nanometals themselves based on their chemical nature without the influence of other variable. Aim of our study therefore is to compare the cytotoxic effect of two types of noble metal NPs focusing on the mechanisms that contribute to cytotoxicity. The study was conducted on murine fibroblasts by selected common used tests. Each of these tests monitors the selected area related to toxicity and together provides a comprehensive view on the issue of interactions of nanoparticles and living cells.

Keywords: cytotoxicity, gold nanoparticles, mechanism of cytotoxicity, silver nanoparticles

Procedia PDF Downloads 254
580 Engineers 'Write' Job Description: Development of English for Specific Purposes (ESP)-Based Instructional Materials for Engineering Students

Authors: Marjorie Miguel

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Globalization offers better career opportunities hence demands more competent professionals efficient for the job. With the transformation of the world industry from competition to collaboration coupled with the rapid development in the field of science and technology, engineers need not only to be technically proficient, but also multilingual-skilled: two characteristics that a global engineer possesses. English often serves as the global language between people from different cultures being the medium mostly used in international business. Ironically, most universities worldwide adapt engineering curriculum heavily built around the language of mathematics not realizing that the goal of an engineer is not only to create and design, but more importantly to promote his creations and designs to the general public through effective communication. This premise led to some developments in the teaching process of English subjects in the tertiary level which include the integration of the technical knowledge related to the area of specialization of the students in the English subjects that they are taking. This is also known as English for Specific Purposes. This study focused on the development of English for Specific Purposes-Based Instructional Materials for Engineering Students of Bulacan State University (BulSU). The materials were tailor-made in which the contents and structure were designed to meet the specific needs of the students as well as the industry. Based on the needs analysis, the needs of the students and the industry were determined to make the study descriptive in nature. The major respondents included fifty engineering students and ten professional engineers from selected institutions. The needs analysis was done and the results showed the common writing difficulties of the students and the writing skills needed among the engineers in the industry. The topics in the instructional materials were established after the needs analysis was conducted. Simple statistical treatment including frequency distribution, percentages, mean, standard deviation, and weighted mean were used. The findings showed that the greatest number of the respondents had an average proficiency rating in writing, and the much-needed skills that must be developed by the engineers are directly related to the preparation and presentation of technical reports about their projects, as well as to the different communications they transmit to their colleagues and superiors. The researcher undertook the following phases in the development of the instructional materials: a design phase, development phase, and evaluation phase. Evaluations are given by some college instructors about the instructional materials generally helped in its usefulness and significance making the study beneficial not only as a career enhancer for BulSU engineering students, but also creating the university one of the educational institutions ready for the new millennium.

Keywords: English for specific purposes, instructional materials, needs analysis, write (right) job description

Procedia PDF Downloads 239
579 An Integrative Review on the Experiences of Integration of Quality Assurance Systems in Universities

Authors: Laura Mion

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Concepts of quality assurance and management are now part of the organizational culture of the Universities. Quality Assurance (QA) systems are, in large part, provided for by national regulatory dictates or supranational indications (such as, for example, at European level are, the ESG Guidelines "European Standard Guidelines"), but their specific definition, in terms of guiding principles, requirements and methodologies, are often delegated to the national evaluation agencies or to the autonomy of individual universities. For this reason, the experiences of implementation of QA systems in different countries and in different universities is an interesting source of information to understand how quality in universities is understood, pursued and verified. The literature often deals with the treatment of the experiences of implementation of QA systems in the individual areas in which the University's activity is carried out - teaching, research, third mission - but only rarely considers quality systems with a systemic and integrated approach, which allows to correlate subjects, actions, and performance in a virtuous circuit of continuous improvement. In particular, it is interesting to understand how to relate the results and uses of the QA in the triple distinction of university activities, identifying how one can cause the performance of the other as a function of an integrated whole and not as an exploit of specific activities or processes conceived in an abstractly atomistic way. The aim of the research is, therefore, to investigate which experiences of "integrated" QA systems are present on the international scene: starting from the experience of European countries that have long shared the Bologna Process for the creation of a European space for Higher Education (EHEA), but also considering experiences from emerging countries that use QA processes to develop their higher education systems to keep them up to date with international levels. The concept of "integration", in this research, is understood in a double meaning: i) between the different areas of activity, in particular between the didactic and research areas, and possibly with the so-called "third mission" "ii) the functional integration between those involved in quality assessment and management and the governance of the University. The paper will present the results of a systematic review conducted according with a method of an integrative review aimed at identifying best practices of quality assurance systems, in individual countries or individual universities, with a high level of integration. The analysis of the material thus obtained has made it possible to grasp common and transversal elements of QA system integration practices or particularly interesting elements and strengths of these experiences that can, therefore, be considered as winning aspects in a QA practice. The paper will present the method of analysis carried out, and the characteristics of the experiences identified, of which the structural elements will be highlighted (level of integration, areas considered, organizational levels included, etc.) and the elements for which these experiences can be considered as best practices.

Keywords: quality assurance, university, integration, country

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578 Bivariate Analyses of Factors That May Influence HIV Testing among Women Living in the Democratic Republic of the Congo

Authors: Danielle A. Walker, Kyle L. Johnson, Patrick J. Fox, Jacen S. Moore

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The HIV Continuum of Care has become a universal model to provide context for the process of HIV testing, linkage to care, treatment, and viral suppression. HIV testing is the first step in moving toward community viral suppression. Countries with a lower socioeconomic status experience the lowest rates of testing and access to care. The Democratic Republic of the Congo is located in the heart of sub-Saharan Africa, where testing and access to care are low and women experience higher HIV prevalence compared to men. In the Democratic Republic of the Congo there is only a 21.6% HIV testing rate among women. Because a critical gap exists between a woman’s risk of contracting HIV and the decision to be tested, this study was conducted to obtain a better understanding of the relationship between factors that could influence HIV testing among women. The datasets analyzed were from the 2013-14 Democratic Republic of the Congo Demographic and Health Survey Program. The data was subset for women with an age range of 18-49 years. All missing cases were removed and one variable was recoded. The total sample size analyzed was 14,982 women. The results showed that there did not seem to be a difference in HIV testing by mean age. Out of 11 religious categories (Catholic, Protestant, Armee de salut, Kimbanguiste, Other Christians, Muslim, Bundu dia kongo, Vuvamu, Animist, no religion, and other), those who identified as Other Christians had the highest testing rate of 25.9% and those identified as Vuvamu had a 0% testing rate (p<0.001). There was a significant difference in testing by religion. Only 0.7% of women surveyed identified as having no religious affiliation. This suggests partnerships with key community and religious leaders could be a tool to increase testing. Over 60% of women who had never been tested for HIV did not know where to be tested. This highlights the need to educate communities on where testing facilities can be located. Almost 80% of women who believed HIV could be transmitted by supernatural means and/or witchcraft had never been tested before (p=0.08). Cultural beliefs could influence risk perception and testing decisions. Consequently, misconceptions need to be considered when implementing HIV testing and prevention programs. Location by province, years of education, and wealth index were also analyzed to control for socioeconomic status. Kinshasa had the highest testing rate of 54.2% of women living there, and both Equateur and Kasai-Occidental had less than a 10% testing rate (p<0.001). As the education level increased up to 12 years, testing increased (p<0.001). Women within the highest quintile of the wealth index had a 56.1% testing rate, and women within the lowest quintile had a 6.5% testing rate (p<0.001). This study concludes that further research is needed to identify culturally competent methods to increase HIV education programs, build partnerships with key community leaders, and improve knowledge on access to care.

Keywords: Democratic Republic of the Congo, cultural beliefs, education, HIV testing

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577 Violence against Women: A Study on the Aggressors' Profile

Authors: Giovana Privatte Maciera, Jair Izaías Kappann

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Introduction: The violence against woman is a complex phenomenon that accompanies the woman throughout her life and is a result of a social, cultural, political and religious construction, based on the differences among the genders. Those differences are felt, mainly, because of the patriarchal system that is still present which just naturalize and legitimate the asymmetry of power. As consequence of the women’s lasting historical and collective effort for a legislation against the impunity of violence against women in the national scenery, it was ordained, in 2006, a law known as Maria da Penha. The law was created as a protective measure for women that were victims of violence and consequently for the punishment of the aggressor. Methodology: Analysis of police inquiries is established by the Police Station of Defense of the Woman of Assis city, by formal authorization of the justice, in the period of 2013 to 2015. For the evaluating of the results will be used the content analysis and the theoretical referential of Psychoanalysis. Results and Discussion: The final analysis of the inquiries demonstrated that the violence against women is reproduced by the society and the aggressor, in most cases it is a member of their own family, mainly the current or former-spouse. The most common kinds of aggression were: the threat bodily harm, and the physical violence, that normally happens accompanied by psychological violence, being the most painful for the victims. The biggest part of the aggressors was white, older than the victim, worker and had primary school. But, unlike the expected, the minority of the aggressors were users of alcohol and/or drugs and possessed children in common with the victim. There is a contrast among the number of victims who already admitted have suffered some type of violence earlier by the same aggressor and the number of victims who has registered the occurrence before. The aggressors often use the discourse of denial in their testimony or try to justify their act like the blame was of the victim. It is believed in the interaction of several factors that can influence the aggressor to commit the abuse, including psychological, personal and sociocultural factors. One hypothesis is that the aggressor has a violence history in the family origin. After the aggressor being judged, condemned or not, usually there is no rehabilitation plan or supervision that enable his change. Conclusions: It has noticed the importance of studying the aggressor’s characteristics and the reasons that took him to commit such violence, making possible the implementation of an appropriate treatment to prevent and reduce the aggressions, as well the creation of programs and actions that enable communication and understanding concerning the theme. This is because the recurrence is still high, since the punitive system is not enough and the law is still ineffective and inefficient in certain aspects and in its own functioning. It is perceived a compulsion in repeat so much for the victims as for the aggressors, because they end involving, almost always, in disturbed and violent relationships, with the relation of subordination-dominance as characteristic.

Keywords: aggressors' profile, gender equality, Maria da Penha law, violence against women

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576 Developing a Culturally Adapted Family Intervention for Relatives Living with Schizophrenia in Oman

Authors: Aziza Al-Sawafi

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Introduction: The evidence of family interventions in schizophrenia is robust primarily in high-income settings. However, they have been adapted to other settings and cultures to improve effectiveness and acceptability. In Oman, there is limited integration of psychosocial interventions in the treatment of schizophrenia. Therefore, the adaptation of family intervention to the Omani culture may facilitate its uptake. Most service users in Oman live with their families outside the healthcare system, and nothing is known about their experience, needs, or resources. Furthermore, understanding caregivers' and mental health professionals' preferences, perceptions, and experience is a fundamental element in the process of intervention development. Therefore, this study aims to develop a culturally sensitive, feasible, and acceptable family intervention for relatives living with schizophrenia in Oman. Method: The Medical Research Council's framework for the evaluation of complex health care interventions provided the conceptual structure for the study. The development phase was carried out, which involved three stages: 1) systematically reviewing the available literature regarding culturally adapted family interventions in the Arab world 2) In-depth interviews with caregivers to explore their experience and perceived needs and preferences regarding intervention 3) A focus group study involving health professionals to explore the acceptability and feasibility of delivering the family intervention in the Omani context. Data synthesis determined the design of the proposed intervention according to the findings obtained from the previous stages. Results: Stage one: The systematic review found limited evidence of culturally-adapted family interventions in the Arab region. However, the cultural adaptation process was comprehensive, and the implementation was reported to be feasible and acceptable. Stage two: The experience of family caregivers illuminated four main themes: burden, stigma, violence, and family needs. Burdens of care included objective and subjective burdens, positive feelings, and coping mechanisms. Caregivers gave their opinion about the content and preference of the intervention from their personal experiences. Stage three: mental health professionals discussed the delivery system of the intervention from a clinical standpoint concerning issues and barriers to implementation. They recommended modifications to the components of the intervention to ensure its acceptability and feasibility in the local setting. Data synthesis was carried out, and the intervention was designed. Conclusion: This study provides evidence of the potential applicability and acceptability of a culturally sensitive family intervention for families of individuals with schizophrenia in Oman. However, more work needs to be done to test the feasibility of the study and overcome the practical challenges.

Keywords: cultural-adaptation, family intervention, Oman, schizophrenia

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575 The Effect of a Reactive Poly (2-Vinyl-2-Oxazoline) Monolayer of Carbon Fiber Surface on the Mechanical Property of Carbon Fiber/Polypropylene Composite Using Maleic Anhydride Grafted Polypropylene

Authors: Teruya Goto, Hokuto Chiba, Tatsuhiro Takahashi

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Carbon fiber reinforced thermoplastic resin using short carbon fiber has been produced by melt mixing and the improvement of mechanical properties has been frequently reported up to now. One of the most frequently reported enhancement has been seen in carbon fiber / polypropylene (PP) composites by adding small amount of maleic anhydride grafted polypropylene (MA-g-PP) into PP matrix. However, the further enhancement of tensile strength and tensile modules has been expected for lightning the composite more. Our present research aims to improve the mechanical property by using a highly reactive monolayer polymer, which can react with both COOH of carbon fiber surface and maleic anhydride of MA-g-PP in the matrix, on carbon fiber for PP/CF composite. It has been known that oxazoline has much higher reactivity with COOH without catalysts, compared with amine group and alcohol OH group. However, oxazoline group has not been used for the interface. To achieve the purpose, poly-2-vinyl-2-oxazoline (Pvozo), having highly reactivity with COOH and maleic anhydride, has been originally synthesized through radical polymerization using 2-vinyl-2-oxazoline as a monomer, resulting in the Mw around 140,000. Monolayer Pvozo chemically reacted on CF was prepared in 1-methoxy-2-propanol solution of Pvozo by heating at 100oC for 3 hours. After this solution treatment, unreacted Pvozo was completely washed out by methanol, resulting the uniform formation of the monolayer Pvozo on CF. Monolayer Pvozo coated CF was melt mixed by with PP and a small amount of MA-g-PP for the preparation of the composite samples using a batch type melt mixer. With performing the tensile strength tests of the composites, the tensile strength of CF/MA-g-PP/PP showed 40% increase, compared to that of CF/PP. While, that of Pvozo coated CF/MA-g-PP/PP exhibited 80% increase, compared to that of CF/PP. To get deeper insight of the dramatic increase, the weight percentage of chemically grafted polymer based on CF was evaluated by dissolving and removing the matrix polymer by xylene using by thermos gravimetric analysis (TGA). The chemically grafted remained polymer was found to be 0.69wt% in CF/PP, 0.98wt% in CF/MA-g-PP/PP, 1.51wt% in Pvozo coated CF/MA-g-PP/PP, suggesting that monolayer Pvozo contributed to the increase of the grafted polymer amount. In addition, the very strong adhesion by Pvozo was confirmed by observing the fractured cross-sectional surface of the composite by scanning electron micrograph (SEM). As a conclusion, the effectiveness of a highly reactive monolayer Pvozo on CF for the enhancement of the mechanical properties of CF/PP composite was demonstrated, which can be interpreted by the clear evidence of the increase of the grafting polymer on CF.

Keywords: CFRTP, interface, oxazoline, polymer graft, mechanical property

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574 Food Insecurity Among Afghan Women Refugees in Pakistan

Authors: Farhana Nosheen, Maleeha Fatima

Abstract:

This study on Afghan refugee women living in Punjab, Pakistan, shows a strong relationship between poor socio-economic status and lower nutritional health status. Pakistan is one of the significant countries accepting refugees from the Afghan war. Universally, refugees are vulnerable to food security and basic life necessities. The in-hand study aimed to investigate food insecurity among afghan refugees who recently migrated to Pakistan. Purposive sampling technique was employed to collect the data from afghan women refugees settled in refugee camp settled in Capital city Islamabad, Pakistan. Data was collected through an interview tool. It revealed from data that the majority of women were underweight, about 74.7% in their reproductive years, which is an alarming situation for the forthcoming children and families. It is also shown that There’s a strong impact of their income level, education, dietary habits and food insecurity on their overall health status. It can also be observed in their Body Mass Index and in their physical appearance; they also show extremely poor levels of hemoglobin which is directly indicated anemic condition, especially iron deficiency anemia among the young Afghan refugee women. The illiteracy rate is about 93.33% among the selected participants as well as a majority of this population has 10-12 family size in comparison with their income level of about 10,000-15,000 Pakistani rupees per month, which can hardly meet their daily food expenditure. Adequate food is rarely accessible to young girls and women due to fewer national and international food aids program available in Pakistan. The majority have pale yellowish skin color (due to low iron content) along with clear white eyes (low hemoglobin level), thin hairs (protein deficiency) and spoon-shaped nails (a direct indicator of low iron level). Data showed a significant relation between appetite and BMI as their appetite is very low, which is directly indicated in their underweight body condition. About 56.67% of the participants had Urinary Tract Infections. The main causes included personal unhygienic conditions and lack of washrooms as well as drinking water facilities in their refugee camps. It is suggested that National and international food aid programs should cater to the nutritional demands of women refugees in the world to protect them from food insecurities as well as future researchers should find out better ways of analysis and treatment plans for such kind of communities who are highly prone to nutritional deficiencies and lack of basic supplies.

Keywords: food insecurity, refugees, women, vulnerable

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573 Effect of Tooth Bleaching Agents on Enamel Demineralisation

Authors: Najlaa Yousef Qusti, Steven J. Brookes, Paul A. Brunton

Abstract:

Background: Tooth discoloration can be an aesthetic problem, and tooth whitening using carbamide peroxide bleaching agents are a popular treatment option. However, there are concerns about possible adverse effects such as demineralisation of the bleached enamel; however, the cause of this demineralisation is unclear. Introduction: Teeth can become stained or discoloured over time. Tooth whitening is an aesthetic solution for tooth discoloration. Bleaching solutions of 10% carbamide peroxide (CP) have become the standard agent used in dentist-prescribed and home-applied ’vital bleaching techniques’. These materials release hydrogen peroxide (H₂O₂), the active whitening agent. However, there is controversy in the literature regarding the effect of bleaching agents on enamel integrity and enamel mineral content. The purpose of this study was to establish if carbamide peroxide bleaching agents affect the acid solubility of enamel (i.e., make teeth more prone to demineralisation). Materials and Methods: Twelve human premolar teeth were sectioned longitudinally along the midline and varnished to leave the natural enamel surface exposed. The baseline behavior of each tooth half in relation to its demineralisation in acid was established by sequential exposure to 4 vials containing 1ml of 10mM acetic acid (1 minute/vial). This was followed by exposure to 10% CP for 8 hours. After washing in distilled water, the tooth half was sequentially exposed to 4 further vials containing acid to test if the acid susceptibility of the enamel had been affected. The corresponding tooth half acted as a control and was exposed to distilled water instead of CP. The mineral loss was determined by measuring [Ca²⁺] and [PO₄³⁻] released in each vial using a calcium ion-selective electrode and the phosphomolybdenum blue method, respectively. The effect of bleaching on the tooth surfaces was also examined using SEM. Results: Exposure to carbamide peroxide did not significantly alter the susceptibility of enamel to acid attack, and SEM of the enamel surface revealed a slight alteration in surface appearance. SEM images of the control enamel surface showed a flat enamel surface with some shallow pits, whereas the bleached enamel appeared with an increase in surface porosity and some areas of mild erosion. Conclusions: Exposure to H₂O₂ equivalent to 10% CP does not significantly increase subsequent acid susceptibility of enamel as determined by Ca²⁺ release from the enamel surface. The effects of bleaching on mineral loss were indistinguishable from distilled water in the experimental system used. However, some surface differences were observed by SEM. The phosphomolybdenum blue method for phosphate is compromised by peroxide bleaching agents due to their oxidising properties. However, the Ca²⁺ electrode is unaffected by oxidising agents and can be used to determine the mineral loss in the presence of peroxides.

Keywords: bleaching, carbamide peroxide, demineralisation, teeth whitening

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572 Food for Health: Understanding the Importance of Food Safety in the Context of Food Security

Authors: Carmen J. Savelli, Romy Conzade

Abstract:

Background: Access to sufficient amounts of safe and nutritious food is a basic human necessity, required to sustain life and promote good health. Food safety and food security are therefore inextricably linked, yet the importance of food safety in this relationship is often overlooked. Methodologies: A literature review and desk study were conducted to examine existing frameworks for discussing food security, especially from an international perspective, to determine the entry points for enhancing considerations for food safety in national and international policies. Major Findings: Food security is commonly understood as the state when all people at all times have physical, social and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life. Conceptually, food security is built upon four pillars including food availability, access, utilization and stability. Within this framework, the safety of food is often wrongly assumed as a given. However, in places where food supplies are insufficient, coping mechanisms for food insecurity are primarily focused on access to food without considerations for ensuring safety. Under such conditions, hygiene and nutrition are often ignored as people shift to less nutritious diets and consume more potentially unsafe foods, in which chemical, microbiological, zoonotic and other hazards can pose serious, acute and chronic health risks. While food supplies might be safe and nutritious, if consumed in quantities insufficient to support normal growth, health and activity, the result is hunger and famine. Recent estimates indicate that at least 842 million people, or roughly one in eight, still suffer from chronic hunger. Even if people eat enough food that is safe, they will become malnourished if the food does not provide the proper amounts of micronutrients and/or macronutrients to meet daily nutritional requirements, resulting in under- or over-nutrition. Two billion people suffer from one or more micronutrient deficiencies and over half a billion adults are obese. Access to sufficient amounts of nutritious food is not enough. If food is unsafe, whether arising from poor quality supplies or inadequate treatment and preparation, it increases the risk of foodborne infections such as diarrhoea. 70% of diarrhoea episodes occurring annually in children under five are due to biologically contaminated food. Conclusions: An integrated approach is needed where food safety and nutrition are systematically introduced into mainstream food system policies and interventions worldwide in order to achieve health and development goals. A new framework, “Food for Health” is proposed to guide policy development and requires all three aspects of food security to be addressed in balance: sufficiency, nutrition and safety.

Keywords: food safety, food security, nutrition, policy

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571 Crash and Injury Characteristics of Riders in Motorcycle-Passenger Vehicle Crashes

Authors: Z. A. Ahmad Noor Syukri, A. J. Nawal Aswan, S. V. Wong

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The motorcycle has become one of the most common type of vehicles used on the road, particularly in the Asia region, including Malaysia, due to its size-convenience and affordable price. This study focuses only on crashes involving motorcycles with passenger cars consisting 43 real world crashes obtained from in-depth crash investigation process from June 2016 till July 2017. The study collected and analyzed vehicle and site parameters obtained during crash investigation and injury information acquired from the patient-treating hospital. The investigation team, consisting of two personnel, is stationed at the Emergency Department of the treatment facility, and was dispatched to the crash scene once receiving notification of the related crashes. The injury information retrieved was coded according to the level of severity using the Abbreviated Injury Scale (AIS) and classified into different body regions. The data revealed that weekend crashes were significantly higher for the night time period and the crash occurrence was the highest during morning hours (commuting to work period) for weekdays. Bad weather conditions play a minimal effect towards the occurrence of motorcycle – passenger vehicle crashes and nearly 90% involved motorcycles with single riders. Riders up to 25 years old are heavily involved in crashes with passenger vehicles (60%), followed by 26-55 year age group with 35%. Male riders were dominant in each of the age segments. The majority of the crashes involved side impacts, followed by rear impacts and cars outnumbered the rest of the passenger vehicle types in terms of crash involvement with motorcycles. The investigation data also revealed that passenger vehicles were the most at-fault counterpart (62%) when involved in crashes with motorcycles and most of the crashes involved situations whereby both of the vehicles are travelling in the same direction and one of the vehicles is in a turning maneuver. More than 80% of the involved motorcycle riders had sustained yellow severity level during triage process. The study also found that nearly 30% of the riders sustained injuries to the lower extremities, while MAIS level 3 injuries were recorded for all body regions except for thorax region. The result showed that crashes in which the motorcycles were found to be at fault were more likely to occur during night and raining conditions. These types of crashes were also found to be more likely to involve other types of passenger vehicles rather than cars and possess higher likelihood in resulting higher ISS (>6) value to the involved rider. To reduce motorcycle fatalities, it first has to understand the characteristics concerned and focus may be given on crashes involving passenger vehicles as the most dominant crash partner on Malaysian roads.

Keywords: motorcycle crash, passenger vehicle, in-depth crash investigation, injury mechanism

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570 Enhanced Field Emission from Plasma Treated Graphene and 2D Layered Hybrids

Authors: R. Khare, R. V. Gelamo, M. A. More, D. J. Late, Chandra Sekhar Rout

Abstract:

Graphene emerges out as a promising material for various applications ranging from complementary integrated circuits to optically transparent electrode for displays and sensors. The excellent conductivity and atomic sharp edges of unique two-dimensional structure makes graphene a propitious field emitter. Graphene analogues of other 2D layered materials have emerged in material science and nanotechnology due to the enriched physics and novel enhanced properties they present. There are several advantages of using 2D nanomaterials in field emission based devices, including a thickness of only a few atomic layers, high aspect ratio (the ratio of lateral size to sheet thickness), excellent electrical properties, extraordinary mechanical strength and ease of synthesis. Furthermore, the presence of edges can enhance the tunneling probability for the electrons in layered nanomaterials similar to that seen in nanotubes. Here we report electron emission properties of multilayer graphene and effect of plasma (CO2, O2, Ar and N2) treatment. The plasma treated multilayer graphene shows an enhanced field emission behavior with a low turn on field of 0.18 V/μm and high emission current density of 1.89 mA/cm2 at an applied field of 0.35 V/μm. Further, we report the field emission studies of layered WS2/RGO and SnS2/RGO composites. The turn on field required to draw a field emission current density of 1μA/cm2 is found to be 3.5, 2.3 and 2 V/μm for WS2, RGO and the WS2/RGO composite respectively. The enhanced field emission behavior observed for the WS2/RGO nanocomposite is attributed to a high field enhancement factor of 2978, which is associated with the surface protrusions of the single-to-few layer thick sheets of the nanocomposite. The highest current density of ~800 µA/cm2 is drawn at an applied field of 4.1 V/μm from a few layers of the WS2/RGO nanocomposite. Furthermore, first-principles density functional calculations suggest that the enhanced field emission may also be due to an overlap of the electronic structures of WS2 and RGO, where graphene-like states are dumped in the region of the WS2 fundamental gap. Similarly, the turn on field required to draw an emission current density of 1µA/cm2 is significantly low (almost half the value) for the SnS2/RGO nanocomposite (2.65 V/µm) compared to pristine SnS2 (4.8 V/µm) nanosheets. The field enhancement factor β (~3200 for SnS2 and ~3700 for SnS2/RGO composite) was calculated from Fowler-Nordheim (FN) plots and indicates emission from the nanometric geometry of the emitter. The field emission current versus time plot shows overall good emission stability for the SnS2/RGO emitter. The DFT calculations reveal that the enhanced field emission properties of SnS2/RGO composites are because of a substantial lowering of work function of SnS2 when supported by graphene, which is in response to p-type doping of the graphene substrate. Graphene and 2D analogue materials emerge as a potential candidate for future field emission applications.

Keywords: graphene, layered material, field emission, plasma, doping

Procedia PDF Downloads 361