Search results for: measuring stress
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5487

Search results for: measuring stress

1227 Assessing the Competence of Oral Surgery Trainees: A Systematic Review

Authors: Chana Pavneet

Abstract:

Background: In more recent years in dentistry, a greater emphasis has been placed on competency-based education (CBE) programmes. Undergraduate and postgraduate curriculums have been reformed to reflect these changes, and adopting a CBE approach has shown to be beneficial to trainees and places an emphasis on continuous lifelong learning. The literature is vast; however, very little work has been done specifically to the assessment of competence in dentistry and even less so in oral surgery. The majority of the literature tends to opinion pieces. Some small-scale studies have been undertaken in this area researching assessment tools which can be used to assess competence in oral surgery. However, there is a lack of general consensus on the preferable assessment methods. The aim of this review is to identify the assessment methods available and their usefulness. Methods: Electronic databases (Medline, Embase, and the Cochrane Database of systematic reviews) were searched. PRISMA guidelines were followed to identify relevant papers. Abstracts of studies were reviewed, and if they met the inclusion criteria, they were included in the review. Papers were reviewed against the critical appraisal skills programme (CASP) checklist and medical education research quality instrument (MERQSI) to assess their quality and identify any bias in a systematic manner. The validity and reliability of each assessment method or tool were assessed. Results: A number of assessment methods were identified, including self-assessment, peer assessment, and direct observation of skills by someone senior. Senior assessment tended to be the preferred method, followed by self-assessment and, finally, peer assessment. The level of training was shown to affect the preferred assessment method, with one study finding peer assessment more useful in postgraduate trainees as opposed to undergraduate trainees. Numerous tools for assessment were identified, including a checklist scale and a global rating scale. Both had their strengths and weaknesses, but the evidence was more favourable for global rating scales in terms of reliability, applicability to more clinical situations, and easier to use for examiners. Studies also looked into trainees’ opinions on assessment tools. Logbooks were not found to be significant in measuring the competence of trainees. Conclusion: There is limited literature exploring the methods and tools which assess the competence of oral surgery trainees. Current evidence shows that the most favourable assessment method and tool may differ depending on the stage of training. More research is required in this area to streamline assessment methods and tools.

Keywords: competence, oral surgery, assessment, trainees, education

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1226 Electronic Device Robustness against Electrostatic Discharges

Authors: Clara Oliver, Oibar Martinez

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This paper is intended to reveal the severity of electrostatic discharge (ESD) effects in electronic and optoelectronic devices by performing sensitivity tests based on Human Body Model (HBM) standard. We explain here the HBM standard in detail together with the typical failure modes associated with electrostatic discharges. In addition, a prototype of electrostatic charge generator has been designed, fabricated, and verified to stress electronic devices, which features a compact high voltage source. This prototype is inexpensive and enables one to do a battery of pre-compliance tests aimed at detecting unexpected weaknesses to static discharges at the component level. Some tests with different devices were performed to illustrate the behavior of the proposed generator. A set of discharges was applied according to the HBM standard to commercially available bipolar transistors, complementary metal-oxide-semiconductor transistors and light emitting diodes. It is observed that high current and voltage ratings in electronic devices not necessarily provide a guarantee that the device will withstand high levels of electrostatic discharges. We have also compared the result obtained by performing the sensitivity tests based on HBM with a real discharge generated by a human. For this purpose, the charge accumulated in the person is monitored, and a direct discharge against the devices is generated by touching them. Every test has been performed under controlled relative humidity conditions. It is believed that this paper can be of interest for research teams involved in the development of electronic and optoelectronic devices which need to verify the reliability of their devices in terms of robustness to electrostatic discharges.

Keywords: human body model, electrostatic discharge, sensitivity tests, static charge monitoring

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1225 A Refrigerated Condition for the Storage of Glucose Test Strips at Health Promoting Hospitals: An Implication for Hospitals with Limited Air Conditioners

Authors: Wanutchaya Duanginta, Napaporn Apiratmateekul, Tippawan Sangkaew, Sunaree Wekinhirun, Kunchit Kongros, Wanvisa Treebuphachatsakul

Abstract:

Thailand has a tropical climate with an average outdoor ambient air temperature of over 30°C, which can exceed manufacturer recommendations for the storage of glucose test strips. This study monitored temperature and humidity at actual sites of five sub-district health promoting hospitals (HPH) in Phitsanulok Province for the storage of glucose test strips in refrigerated conditions. Five calibrated data loggers were placed at the actual sites for glucose test strip storage at five HPHs for 8 weeks between April and June. For the stress test, two lot numbers of glucose test strips, each with two glucose meters, were kept in a plastic box with desiccants and placed in a refrigerator with the temperature calibrated to 4°C and at room temperature (RT). Temperature and humidity in the refrigerator and at RT were measured every hour for 30 days. The mean temperature for storing test strips at the five HPHs ranged from 29°C to 33°C, and three of the five HPHs (60%) had a mean temperature above 30°C. The refrigerator temperatures were 3.8 ± 2.0°C (2.0°C to 6.5°C), and relative humidity was 51 ± 2% (42 to 54%). The maximum of blood glucose testing by glucose meters when the test strips were stored in a refrigerator were not significantly different (p > 0.05) from unstressed test strips for both glucose meters using amperometry-GDH-PQQ and amperometry-GDH-FAD principles. Opening the test strip vial daily resulted in higher variation than when refrigerated after a single-use. However, the variations were still within an acceptable range. This study concludes that glucose tested strips can be stored in plastic boxes in a refrigerator if it is well-controlled for temperature and humidity. Storage of glucose-tested strips in the refrigerator during hot and humid weather may be useful for HPHs with limited air conditioners.

Keywords: environmental stressed test, thermal stressed test, quality control, point-of-care testing

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1224 Environmental Fatigue Analysis for Control Rod Drive Mechanisms Seal House

Authors: Xuejiao Shao, Jianguo Chen, Xiaolong Fu

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In this paper, the elastoplastic strain correction factor computed by software of ANSYS was modified, and the fatigue usage factor in air was also corrected considering in water under reactor operating condition. The fatigue of key parts on control rod drive mechanisms was analyzed considering the influence of environmental fatigue caused by the coolant in the react pressure vessel. The elastoplastic strain correction factor was modified by analyzing thermal and mechanical loads separately referring the rules of RCC-M 2002. The new elastoplastic strain correction factor Ke(mix) is computed to replace the original Ke computed by the software of ANSYS when evaluating the fatigue produced by thermal and mechanical loads together. Based on the Ke(mix) and the usage cycle and fatigue design curves, the new range of primary plus secondary stresses was evaluated to obtain the final fatigue usage factor. The results show that the precision of fatigue usage factor can be elevated by using modified Ke when the amplify of the primary and secondary stress is large to some extent. One approach has been proposed for incorporating the environmental effects considering the effects of reactor coolant environments on fatigue life in terms of an environmental correction factor Fen, which is the ratio of fatigue life in air at room. To incorporate environmental effects into the RCCM Code fatigue evaluations, the fatigue usage factor based on the current Code design curves is multiplied by the correction factor. The contribution of environmental effects to results is discussed. Fatigue life decreases logarithmically with decreasing strain rate below 10%/s, which is insensitive to strain rate when temperatures below 100°C.

Keywords: environmental fatigue, usage factor, elastoplastic strain correction factor, environmental correction

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1223 The Relationship Between Soldiers’ Psychological Resilience, Leadership Style and Organisational Commitment

Authors: Rosita Kanapeckaite

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The modern operational military environment is a combination of factors such as change, uncertainty, complexity and ambiguity. Stiehm (2002) refers to such situations as VUCA situations. VUCA is an acronym commonly used to describe the volatility, uncertainty, complexity and ambiguity of various situations and conditions. Increasingly fast-paced military operations require military personnel to demonstrate readiness and resilience under stressful conditions in order to maintain the optimum cognitive and physical performance necessary to achieve success. Military resilience can be defined as the ability to cope with the negative effects of setbacks and associated stress on military performance and combat effectiveness. In the volatile, uncertain, complex and ambiguous modern operational environment, both current and future operations require and place a higher priority on enhancing and maintaining troop readiness and resilience to win decisively in multidimensional combat. This paper explores the phenomenon of soldiers' psychological resilience, theories of leadership, and commitment to the organisation. The aim of the study is to examine the relationship between soldiers' psychological resilience, leadership style and commitment to the organisation. The study involved 425 professional soldiers, the research method was a questionnaire survey. The instruments used were measures of psychological resilience, leadership styles and commitment to the organisation. Results: transformational leadership style predicts higher psychological resilience, and psychologically resilient professional servicemen are more committed to the organisation. The study confirms the importance of soldiers' psychological resilience for their commitment to the organisation. The paper also discusses practical applications.

Keywords: resilience, commitment, solders, leadership style

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1222 Perception of Healthcare Workers Regarding the Psychological Impact of COVID-19 on Their Children

Authors: Saima Batool, Saima Rafique

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Background and Objective: Pandemics like COVID-19 adversely affect children’s behavior and psychological development by disrupting routine life activities. Children of healthcare workers are exposed additionally due to the fear of parental exposure to the virus. The objective of this study was to assess the perception of frontline healthcare workers (HCWs) regarding the psychological impact of the COVID-19 pandemic on their children. We also sought to identify the difference in the psychological impact on children of male and female healthcare workers. Methods: A survey questionnaire was developed comprising 10 questions about the perception of HCWs regarding the psychological impact of COVID-19 on their children. It was distributed both online and face-to-face among 150 healthcare professionals working in training and non-training posts in 4 public and 5 nongovernment hospitals in Pakistan. The mean and standard deviation were calculated for each survey item using Statistical Package for the Social Sciences 26.0. Results: The response rate was 71.3%, and the majority (64.2%) of the healthcare professionals were ≥30 years of age. Ninety-two HCWs (85.98%) either agreed or strongly agreed that parental separation from their kids for long hours during the pandemic had a negative psychological impact on their children. There was a significant difference in the perceived psychological impact of COVID-19 on the children of male and female HCWs, with a mean survey score of 2.29 ± 1.82 and 1.69 ± 0.79, respectively (t = 2.29, p-value = 0.024). Conclusion: Children of healthcare workers experience more stress and anxiety because of long duty hours and working in high-risk settings. Continuous psychological support and counseling services may be adopted formally to prevent unforeseen adverse events or any long-term negative impact on their physical and mental health.

Keywords: healthcare workers, pandemic, COVID-19, anxiety, psychological

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1221 Bioleaching of Metals Contained in Spent Catalysts by Acidithiobacillus thiooxidans DSM 26636

Authors: Andrea M. Rivas-Castillo, Marlenne Gómez-Ramirez, Isela Rodríguez-Pozos, Norma G. Rojas-Avelizapa

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Spent catalysts are considered as hazardous residues of major concern, mainly due to the simultaneous presence of several metals in elevated concentrations. Although hydrometallurgical, pyrometallurgical and chelating agent methods are available to remove and recover some metals contained in spent catalysts; these procedures generate potentially hazardous wastes and the emission of harmful gases. Thus, biotechnological treatments are currently gaining importance to avoid the negative impacts of chemical technologies. To this end, diverse microorganisms have been used to assess the removal of metals from spent catalysts, comprising bacteria, archaea and fungi, whose resistance and metal uptake capabilities differ depending on the microorganism tested. Acidophilic sulfur oxidizing bacteria have been used to investigate the biotreatment and extraction of valuable metals from spent catalysts, namely Acidithiobacillus thiooxidans and Acidithiobacillus ferroxidans, as they present the ability to produce leaching agents such as sulfuric acid and sulfur oxidation intermediates. In the present work, the ability of A. thiooxidans DSM 26636 for the bioleaching of metals contained in five different spent catalysts was assessed by growing the culture in modified Starkey mineral medium (with elemental sulfur at 1%, w/v), and 1% (w/v) pulp density of each residue for up to 21 days at 30 °C and 150 rpm. Sulfur-oxidizing activity was periodically evaluated by determining sulfate concentration in the supernatants according to the NMX-k-436-1977 method. The production of sulfuric acid was assessed in the supernatants as well, by a titration procedure using NaOH 0.5 M with bromothymol blue as acid-base indicator, and by measuring pH using a digital potentiometer. On the other hand, Inductively Coupled Plasma - Optical Emission Spectrometry was used to analyze metal removal from the five different spent catalysts by A. thiooxidans DSM 26636. Results obtained show that, as could be expected, sulfuric acid production is directly related to the diminish of pH, and also to highest metal removal efficiencies. It was observed that Al and Fe are recurrently removed from refinery spent catalysts regardless of their origin and previous usage, although these removals may vary from 9.5 ± 2.2 to 439 ± 3.9 mg/kg for Al, and from 7.13 ± 0.31 to 368.4 ± 47.8 mg/kg for Fe, depending on the spent catalyst proven. Besides, bioleaching of metals like Mg, Ni, and Si was also obtained from automotive spent catalysts, which removals were of up to 66 ± 2.2, 6.2±0.07, and 100±2.4, respectively. Hence, the data presented here exhibit the potential of A. thiooxidans DSM 26636 for the simultaneous bioleaching of metals contained in spent catalysts from diverse provenance.

Keywords: bioleaching, metal removal, spent catalysts, Acidithiobacillus thiooxidans

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1220 Memory Consolidation: Application of Retrieval Strategies in the Classroom

Authors: Eric Tardif, Nicolas Meylan

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Recent studies suggest that the consolidation of episodic memory is better achieved through repeated retrieval than with the use of concept mapping or repeated study. Although such laboratory results highly appeal to educationalists, it remains to be shown whether they can be directly used in a classroom setting. Forty-five college students (42 girls; mean age 16.1 y/o) were asked to remember pairs of biology-related words (e.g. mitochondria-energy) in two configurations. The first configuration consisted of a three-minute study of pairs of words followed by a final one-minute test in which the first word of a pair was shown and the subject asked to write down the second associated word. This procedure was repeated three times. The second configuration consisted of a one-minute study of a list of pairs of words, which was immediately followed by a one-minute test. This procedure was repeated 6 times. Subjects filled out a small questionnaire assessing their general mood, level of fatigue, stress and motivation to do the exercise. One week later, subjects were given a final test using the same words. A total of 8 lists of words were studied and tested during the semester. Results showed that subjects recalled more correct words when using the second configuration, both within the study period and one week later, confirming laboratory findings. However, the general performance (mean items recalled) as well as the motivation to do the exercise gradually decreased during the semester. Motivation was positively correlated with performance (r=0.77, p<0.05). The results suggest that laboratory findings may provide some applications in education but other variables inherent to the classroom setting must also be considered.

Keywords: long-term, episodic memory, consolidation, retrieval, school setting

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1219 Orthogonal Metal Cutting Simulation of Steel AISI 1045 via Smoothed Particle Hydrodynamic Method

Authors: Seyed Hamed Hashemi Sohi, Gerald Jo Denoga

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Machining or metal cutting is one of the most widely used production processes in industry. The quality of the process and the resulting machined product depends on parameters like tool geometry, material, and cutting conditions. However, the relationships of these parameters to the cutting process are often based mostly on empirical knowledge. In this study, computer modeling and simulation using LS-DYNA software and a Smoothed Particle Hydrodynamic (SPH) methodology, was performed on the orthogonal metal cutting process to analyze three-dimensional deformation of AISI 1045 medium carbon steel during machining. The simulation was performed using the following constitutive models: the Power Law model, the Johnson-Cook model, and the Zerilli-Armstrong models (Z-A). The outcomes were compared against the simulated results obtained by Cenk Kiliçaslan using the Finite Element Method (FEM) and the empirical results of Jaspers and Filice. The analysis shows that the SPH method combined with the Zerilli-Armstrong constitutive model is a viable alternative to simulating the metal cutting process. The tangential force was overestimated by 7%, and the normal force was underestimated by 16% when compared with empirical values. The simulation values for flow stress versus strain at various temperatures were also validated against empirical values. The SPH method using the Z-A model has also proven to be robust against issues of time-scaling. Experimental work was also done to investigate the effects of friction, rake angle and tool tip radius on the simulation.

Keywords: metal cutting, smoothed particle hydrodynamics, constitutive models, experimental, cutting forces analyses

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1218 Environmental Resilience in Sustainability Outcomes of Spatial-Economic Model Structure on the Topology of Construction Ecology

Authors: Moustafa Osman Mohammed

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The resilient and sustainable of construction ecology is essential to world’s socio-economic development. Environmental resilience is crucial in relating construction ecology to topology of spatial-economic model. Sustainability of spatial-economic model gives attention to green business to comply with Earth’s System for naturally exchange patterns of ecosystems. The systems ecology has consistent and periodic cycles to preserve energy and materials flow in Earth’s System. When model structure is influencing communication of internal and external features in system networks, it postulated the valence of the first-level spatial outcomes (i.e., project compatibility success). These instrumentalities are dependent on second-level outcomes (i.e., participant security satisfaction). These outcomes of model are based on measuring database efficiency, from 2015 to 2025. The model topology has state-of-the-art in value-orientation impact and correspond complexity of sustainability issues (e.g., build a consistent database necessary to approach spatial structure; construct the spatial-economic model; develop a set of sustainability indicators associated with model; allow quantification of social, economic and environmental impact; use the value-orientation as a set of important sustainability policy measures), and demonstrate environmental resilience. The model is managing and developing schemes from perspective of multiple sources pollutants through the input–output criteria. These criteria are evaluated the external insertions effects to conduct Monte Carlo simulations and analysis for using matrices in a unique spatial structure. The balance “equilibrium patterns” such as collective biosphere features, has a composite index of the distributed feedback flows. These feedback flows have a dynamic structure with physical and chemical properties for gradual prolong of incremental patterns. While these structures argue from system ecology, static loads are not decisive from an artistic/architectural perspective. The popularity of system resilience, in the systems structure related to ecology has not been achieved without the generation of confusion and vagueness. However, this topic is relevant to forecast future scenarios where industrial regions will need to keep on dealing with the impact of relative environmental deviations. The model attempts to unify analytic and analogical structure of urban environments using database software to integrate sustainability outcomes where the process based on systems topology of construction ecology.

Keywords: system ecology, construction ecology, industrial ecology, spatial-economic model, systems topology

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1217 Effects of Vertimax Training on Agility, Quickness and Acceleration

Authors: Dede Basturk, Metin Kaya, Halil Taskin, Nurtekin Erkmen

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In total, 29 students studying in Selçuk University Physical Training and Sports School who are recreationally active participated voluntarilyin this study which was carried out in order to examine effects of Vertimax trainings on agility, quickness and acceleration. 3 groups took their parts in this study as Vertimax training group (N=10), Ordinary training group (N=10) and Control group (N=9). Measurements were carried out in performance laboratory of Selçuk University Physical Training and Sports School. A training program for quickness and agility was followed up for subjects 3 days a week (Monday, Wednesday, Friday) for 8 weeks. Subjects taking their parts in vertimax training group and ordinary training group participated in the training program for quickness and agility. Measurements were applied as pre-test and post-test. Subjects of vertimax training group followed the training program with vertimax device and subjects of ordinary training group followed the training program without vertimax device. As to control group who are recreationally active, they did not participate in any program. 4 gate photocells were used for measuring and measurement of distances was carried out in m. Furthermore, single gate photocell and honi were used for agility test. Measurements started with 15 minutes of warm-up. Acceleration, quickness and agility tests were applied on subjects. 3 measurements were made for each subject at 3 minutes resting intervals. The best rating of three measurements was recorded. 5 m quickness pre-test value of vertimax training groups has been determined as 1,11±0,06 s and post-test value has been determined as 1,06 ± 0,08 s (P<0,05). 5 m quickness pre-test value of ordinary training group has been determined as 1,11±0,06 s and post-test value has been determined as 1,07±0,07 s (P<0,05).5 m quickness pre-test value of control group has been determined as 1,13±0,08 s and post-test value has been determined as 1,10 ± 0,07 s (P>0,05). Upon examination of 10 m acceleration value before and after the training, 10 m acceleration pre-test value of vertimax training group has been determined as 1,82 ± 0,07 s and post-test value has been determined as 1,76±0,83 s (P>0,05). 10 m acceleration pre-test value of ordinary training group has been determined as 1,83±0,05 s and post-test value has been determined as 1,78 ± 0,08 s (P>0,05).10 m acceleration pre-test value of control group has been determined as 1,87±0,11 s and post-test value has been determined as 1,83 ± 0,09 s (P>0,05). Upon examination of 15 m acceleration value before and after the training, 15 m acceleration pre-test value of vertimax training group has been determined as 2,52±0,10 s and post-test value has been determined as 2,46 ± 0,11 s (P>0,05).15 m acceleration pre-test value of ordinary training group has been determined as 2,52±0,05 s and post-test value has been determined as 2,48 ± 0,06 s (P>0,05). 15 m acceleration pre-test value of control group has been determined as 2,55 ± 0,11 s and post-test value has been determined as 2,54 ± 0,08 s (P>0,05).Upon examination of agility performance before and after the training, agility pre-test value of vertimax training group has been determined as 9,50±0,47 s and post-test value has been determined as 9,66 ± 0,47 s (P>0,05). Agility pre-test value of ordinary training group has been determined as 9,99 ± 0,05 s and post-test value has been determined as 9,86 ± 0,40 s (P>0,05). Agility pre-test value of control group has been determined as 9,74 ± 0,45 s and post-test value has been determined as 9,92 ± 0,49 s (P>0,05). Consequently, it has been observed that quickness and acceleration features were developed significantly following 8 weeks of vertimax training program and agility features were not developed significantly. It is suggested that training practices used for the study may be used for situations which may require sudden moves and in order to attain the maximum speed in a short time. Nevertheless, it is also suggested that this training practice does not make contribution in development of moves which may require sudden direction changes. It is suggested that productiveness and innovation may come off in terms of training by using various practices of vertimax trainings.

Keywords: vertimax, training, quickness, agility, acceleration

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1216 Assessment of in vitro Antioxidant and Anti-Inflammatory Potentials of Methanol Extract of Chrysophyllum albidum Cotyledon

Authors: Christianah Adebimpe Dare, Nelson Oghenebrorhie Elvis

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This study was aimed at analysing the phytochemicals in Chrysophyllum albidum cotyledon extract and their in vitro antioxidant and anti-inflammatory effects. The star apple fruit was bought at Igbona market Osogbo, Osun State, Nigeria. The seed from the fruit was removed and defatted. The residue was exhaustively extracted with methanol. The Chrysophyllum albidum cotyledon methanol extract (CCME) was phytochemically screened, flavonoids and phenol contents, antioxidant and anti-inflammatory assays were carried out on the extract using standard procedures. Phytochemicals analysis revealed the presence of steroids, tannins, flavonoid, saponin, triterpenes, and xanthoproteins. The phenolic concentration, total flavonoids concentration, and total sugar concentration were found to be 26.72 ± 0.048 µgTAE/mg, 23.12 ± 1.92µg of Rutin equivalent (RTE)/mg (10.49 ± 1.12µg of Quercetin equivalent (QE/mg) and 778.38 ± 12.82 µg of glucose/ml, respectively. The extract demonstrated significant inhibitory effect compared with the standards as potent antioxidant with percentage inhibition of DPPH as 38.10 %-39.51 %, lipid peroxidation as 45.85 %-65.85 %; ferric reducing power showed linear correlation to the standard and the anti-inflammatory potential with 22.06 %-26.37 % protection of the human red blood membrane and the percentage inhibition of denaturation of albumin 3.42 %-7.32 %. The study showed that C. albidum cotyledon methanol extract is a potent antioxidant and anti-inflammatory agent to combat oxidative stress and pathological diseases caused by reactive species.

Keywords: albumin denaturation, free radicals, lipid peroxidation, reactive species

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1215 Food Supplements and Natural Products to Slow Down Biological Aging

Authors: Coppa Federica, Iannello Giulia, Pennisi Stefania, Giuffrida Graziella, Lo Faro Riccardo, Cartelli Simone, Ferruggia Greta, Brundo Maria Violetta

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In recent years, a new field of basic research has emerged: the biology and physiology of extracellular vesicles and their application in diagnostics and therapy. In particular, exosomes attract the scientific community as nanovesicles of endosomal origin, which can be secreted by a variety of cells and are found in all biological fluids. Exosomes have recently gained attention also in the cosmetic field: in fact, they are used in creams, serums and masks for topical use, proving to have a series of therapeutic and anti-aging benefits. To date, the oral administration of exosomes is the subject of attention because it represents a non-invasive and efficient method for delivering bioactive molecules into the intestine. We decided to focus our research on the creation of a food supplement that contains various bioactive factors, vitamins, and a new technology called AMPLEX PLUS, containing a mixture of 20 different biologically active factors (GF20) and exosomes isolated and purified from bovine colostrum. We have demonstrated in vitro that this new supplement acts on telomerase, slowing down cell aging. Amplex plus increased the proliferation rate of cells and the addition of it reduced the rate of telomere shortening. Under oxidative stress conditions (H2O2 – induced), the TSR increased; however, treatment with colostrum appeared to attenuate this increase. In particular, after 2 weeks of treatment, AMPLEX plus increased the proliferation rate of cells and exerted a protective effect on telomere length erosion, reducing the rate of its shortening.

Keywords: AMPLEX PLUS, colostrum, exosomes, telomerase

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1214 Acrylic Microspheres-Based Microbial Bio-Optode for Nitrite Ion Detection

Authors: Siti Nur Syazni Mohd Zuki, Tan Ling Ling, Nina Suhaity Azmi, Chong Kwok Feng, Lee Yook Heng

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Nitrite (NO2-) ion is used prevalently as a preservative in processed meat. Elevated levels of nitrite also found in edible bird’s nests (EBNs). Consumption of NO2- ion at levels above the health-based risk may cause cancer in humans. Spectrophotometric Griess test is the simplest established standard method for NO2- ion detection, however, it requires careful control of pH of each reaction step and susceptible to strong oxidants and dyeing interferences. Other traditional methods rely on the use of laboratory-scale instruments such as GC-MS, HPLC and ion chromatography, which cannot give real-time response. Therefore, it is of significant need for devices capable of measuring nitrite concentration in-situ, rapidly and without reagents, sample pretreatment or extraction step. Herein, we constructed a microspheres-based microbial optode for visual quantitation of NO2- ion. Raoutella planticola, the bacterium expressing NAD(P)H nitrite reductase (NiR) enzyme has been successfully extracted by microbial technique from EBN collected from local birdhouse. The whole cells and the lipophilic Nile Blue chromoionophore were physically absorbed on the photocurable poly(n-butyl acrylate-N-acryloxysuccinimide) [poly (nBA-NAS)] microspheres, whilst the reduced coenzyme NAD(P)H was covalently immobilized on the succinimide-functionalized acrylic microspheres to produce a reagentless biosensing system. Upon the NiR enzyme catalyzes the oxidation of NAD(P)H to NAD(P)+, NO2- ion is reduced to ammonium hydroxide, and that a colour change from blue to pink of the immobilized Nile Blue chromoionophore is perceived as a result of deprotonation reaction increasing the local pH in the microspheres membrane. The microspheres-based optosensor was optimized with a reflectance spectrophotometer at 639 nm and pH 8. The resulting microbial bio-optode membrane could quantify NO2- ion at 0.1 ppm and had a linear response up to 400 ppm. Due to the large surface area to mass ratio of the acrylic microspheres, it allows efficient solid state diffusional mass transfer of the substrate to the bio-recognition phase, and achieve the steady state response as fast as 5 min. The proposed optical microbial biosensor requires no sample pre-treatment step and possesses high stability as the whole cell biocatalyst provides protection to the enzymes from interfering substances, hence it is suitable for measurements in contaminated samples.

Keywords: acrylic microspheres, microbial bio-optode, nitrite ion, reflectometric

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1213 Seismic Loss Assessment for Peruvian University Buildings with Simulated Fragility Functions

Authors: Jose Ruiz, Jose Velasquez, Holger Lovon

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Peruvian university buildings are critical structures for which very little research about its seismic vulnerability is available. This paper develops a probabilistic methodology that predicts seismic loss for university buildings with simulated fragility functions. Two university buildings located in the city of Cusco were analyzed. Fragility functions were developed considering seismic and structural parameters uncertainty. The fragility functions were generated with the Latin Hypercube technique, an improved Montecarlo-based method, which optimizes the sampling of structural parameters and provides at least 100 reliable samples for every level of seismic demand. Concrete compressive strength, maximum concrete strain and yield stress of the reinforcing steel were considered as the key structural parameters. The seismic demand is defined by synthetic records which are compatible with the elastic Peruvian design spectrum. Acceleration records are scaled based on the peak ground acceleration on rigid soil (PGA) which goes from 0.05g to 1.00g. A total of 2000 structural models were considered to account for both structural and seismic variability. These functions represent the overall building behavior because they give rational information regarding damage ratios for defined levels of seismic demand. The university buildings show an expected Mean Damage Factor of 8.80% and 19.05%, respectively, for the 0.22g-PGA scenario, which was amplified by the soil type coefficient and resulted in 0.26g-PGA. These ratios were computed considering a seismic demand related to 10% of probability of exceedance in 50 years which is a requirement in the Peruvian seismic code. These results show an acceptable seismic performance for both buildings.

Keywords: fragility functions, university buildings, loss assessment, Montecarlo simulation, latin hypercube

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1212 Bed Evolution under One-Episode Flushing in a Truck Sewer in Paris, France

Authors: Gashin Shahsavari, Gilles Arnaud-Fassetta, Alberto Campisano, Roberto Bertilotti, Fabien Riou

Abstract:

Sewer deposits have been identified as a major cause of dysfunctions in combined sewer systems regarding sewer management, which induces different negative consequents resulting in poor hydraulic conveyance, environmental damages as well as worker’s health. In order to overcome the problematics of sedimentation, flushing has been considered as the most operative and cost-effective way to minimize the sediments impacts and prevent such challenges. Flushing, by prompting turbulent wave effects, can modify the bed form depending on the hydraulic properties and geometrical characteristics of the conduit. So far, the dynamics of the bed-load during high-flow events in combined sewer systems as a complex environment is not well understood, mostly due to lack of measuring devices capable to work in the “hostile” in combined sewer system correctly. In this regards, a one-episode flushing issue from an opening gate valve with weir function was carried out in a trunk sewer in Paris to understanding its cleansing efficiency on the sediments (thickness: 0-30 cm). During more than 1h of flushing within 5 m distance in downstream of this flushing device, a maximum flowrate and a maximum level of water have been recorded at 5 m in downstream of the gate as 4.1 m3/s and 2.1 m respectively. This paper is aimed to evaluate the efficiency of this type of gate for around 1.1 km (from the point -50 m to +1050 m in downstream from the gate) by (i) determining bed grain-size distribution and sediments evolution through the sewer channel, as well as their organic matter content, and (ii) identifying sections that exhibit more changes in their texture after the flush. For the first one, two series of sampling were taken from the sewer length and then analyzed in laboratory, one before flushing and second after, at same points among the sewer channel. Hence, a non-intrusive sampling instrument has undertaken to extract the sediments smaller than the fine gravels. The comparison between sediments texture after the flush operation and the initial state, revealed the most modified zones by the flush effect, regarding the sewer invert slope and hydraulic parameters in the zone up to 400 m from the gate. At this distance, despite the increase of sediment grain-size rages, D50 (median grain-size) varies between 0.6 mm and 1.1 mm compared to 0.8 mm and 10 mm before and after flushing, respectively. Overall, regarding the sewer channel invert slope, results indicate that grains smaller than sands (< 2 mm) are more transported to downstream along about 400 m from the gate: in average 69% before against 38% after the flush with more dispersion of grain-sizes distributions. Furthermore, high effect of the channel bed irregularities on the bed material evolution has been observed after the flush.

Keywords: bed-load evolution, combined sewer systems, flushing efficiency, sediments transport

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1211 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study

Authors: Amna bibi, Hina Rana

Abstract:

In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.

Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society

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1210 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study”

Authors: Amna Bibi, Hina Rana

Abstract:

In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.

Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society

Procedia PDF Downloads 31
1209 Reflective Thinking and Experiential Learning – A Quasi-Experimental Quanti-Quali Response to Greater Diversification of Activities, Greater Integration of Student Profiles

Authors: Paulo Sérgio Ribeiro de Araújo Bogas

Abstract:

Although several studies have assumed (at least implicitly) that learners' approaches to learning develop into deeper approaches to higher education, there appears to be no clear theoretical basis for this assumption and no empirical evidence. As a scientific contribution to this discussion, a pedagogical intervention of a quasi-experimental nature was developed, with a mixed methodology, evaluating the intervention within a single curricular unit of Marketing, using cases based on real challenges of brands, business simulation, and customer projects. Primary and secondary experiences were incorporated in the intervention: the primary experiences are the experiential activities themselves; the secondary experiences result from the primary experience, such as reflection and discussion in work teams. A diversified learning relationship was encouraged through the various connections between the different members of the learning community. The present study concludes that in the same context, the student's responses can be described as students who reinforce the initial deep approach, students who maintain the initial deep approach level, and others who change from an emphasis on the deep approach to one closer to superficial. This typology did not always confirm studies reported in the literature, namely, whether the initial level of deep processing would influence the superficial and the opposite. The result of this investigation points to the inclusion of pedagogical and didactic activities that integrate different motivations and initial strategies, leading to the possible adoption of deep approaches to learning since it revealed statistically significant differences in the difference in the scores of the deep/superficial approach and the experiential level. In the case of real challenges, the categories of “attribution of meaning and meaning of studied” and the possibility of “contact with an aspirational context” for their future professional stand out. In this category, the dimensions of autonomy that will be required of them were also revealed when comparing the classroom context of real cases and the future professional context and the impact they may have on the world. Regarding the simulated practice, two categories of response stand out: on the one hand, the motivation associated with the possibility of measuring the results of the decisions taken, an awareness of oneself, and, on the other hand, the additional effort that this practice required for some of the students.

Keywords: experiential learning, higher education, mixed methods, reflective learning, marketing

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1208 Functional Neurocognitive Imaging (fNCI): A Diagnostic Tool for Assessing Concussion Neuromarker Abnormalities and Treating Post-Concussion Syndrome in Mild Traumatic Brain Injury Patients

Authors: Parker Murray, Marci Johnson, Tyson S. Burnham, Alina K. Fong, Mark D. Allen, Bruce McIff

Abstract:

Purpose: Pathological dysregulation of Neurovascular Coupling (NVC) caused by mild traumatic brain injury (mTBI) is the predominant source of chronic post-concussion syndrome (PCS) symptomology. fNCI has the ability to localize dysregulation in NVC by measuring blood-oxygen-level-dependent (BOLD) signaling during the performance of fMRI-adapted neuropsychological evaluations. With fNCI, 57 brain areas consistently affected by concussion were identified as PCS neural markers, which were validated on large samples of concussion patients and healthy controls. These neuromarkers provide the basis for a computation of PCS severity which is referred to as the Severity Index Score (SIS). The SIS has proven valuable in making pre-treatment decisions, monitoring treatment efficiency, and assessing long-term stability of outcomes. Methods and Materials: After being scanned while performing various cognitive tasks, 476 concussed patients received an SIS score based on the neural dysregulation of the 57 previously identified brain regions. These scans provide an objective measurement of attentional, subcortical, visual processing, language processing, and executive functioning abilities, which were used as biomarkers for post-concussive neural dysregulation. Initial SIS scores were used to develop individualized therapy incorporating cognitive, occupational, and neuromuscular modalities. These scores were also used to establish pre-treatment benchmarks and measure post-treatment improvement. Results: Changes in SIS were calculated in percent change from pre- to post-treatment. Patients showed a mean improvement of 76.5 percent (σ= 23.3), and 75.7 percent of patients showed at least 60 percent improvement. Longitudinal reassessment of 24 of the patients, measured an average of 7.6 months post-treatment, shows that SIS improvement is maintained and improved, with an average of 90.6 percent improvement from their original scan. Conclusions: fNCI provides a reliable measurement of NVC allowing for identification of concussion pathology. Additionally, fNCI derived SIS scores direct tailored therapy to restore NVC, subsequently resolving chronic PCS resulting from mTBI.

Keywords: concussion, functional magnetic resonance imaging (fMRI), neurovascular coupling (NVC), post-concussion syndrome (PCS)

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1207 Parametric Study for Optimal Design of Hybrid Bridge Joint

Authors: Bongsik Park, Jae Hyun Park, Jae-Yeol Cho

Abstract:

Mixed structure, which is a kind of hybrid system, is incorporating steel beam and prestressed concrete beam. Hybrid bridge adopting mixed structure have some merits. Main span length can be made longer by using steel as main span material. In case of cable-stayed bridge having asymmetric span length, negative reaction at side span can be restrained without extra restraining devices by using weight difference between main span material and side span material. However angle of refraction might happen because of rigidity difference between materials and stress concentration also might happen because of abnormal loading transmission at joint in the hybrid bridge. Therefore the joint might be a weak point of the structural system and it needs to pay attention to design of the joint. However, design codes and standards about the joint in the hybrid-bridge have not been established so the joint designs in most of construction cases have been very conservative or followed previous design without extra verification. In this study parametric study using finite element analysis for optimal design of hybrid bridge joint is conducted. Before parametric study, finite element analysis was conducted based on previous experimental data and it is verified that analysis result approximated experimental data. Based on the finite element analysis results, parametric study was conducted. The parameters were selected as those have influences on joint behavior. Based on the parametric study results, optimal design of hybrid bridge joint has been determined.

Keywords: parametric study, optimal design, hybrid bridge, finite element analysis

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1206 Effects of Microbial Biofertilization on Nodulation, Nitrogen Fixation, and Yield of Lablab purpureus

Authors: Benselama Amel, Ounane S. Mohamed, Bekki Abdelkader

Abstract:

A collection of 20 isolates from fresh Nodules of the legume plant Lablab purpureus was isolated. These isolates have been authenticated by seedling inoculation grown in jars containing sand. The results obtained after two months of culture have revealed that the 20 isolates (100% of the isolates) are able to nodulate their host plants. The results obtained were analyzed statistically by ANOVA using the software statistica and had shown that the effect of the inoculation has significantly improved all the growth parameters (the height of the plant and the dry weight of the aerial parts and roots, and the number of nodules). We have evaluated the tolerance of all strains of the collection to the major stress factors as the salinity, pH and extreme temperature. The osmotolerance reached a concentration up to 1710mm of NaCl. The strains were also able to grow on a wide range of pH, ranging from 4.5 to 9.5, and temperature, between 4°C and 40°C. Also, we tested the effect of the acidity, aluminum and ferric deficit on the Lablab-rhizobia symbiosis. Lablab purpureus has not been affected by the presence of high concentrations of aluminum. On the other hand, iron deficiency has caused a net decrease in the dry biomass of the aerial part. The results of all the phenotypic characters have been treated by the statistical Minitab software, the numerical analysis had shown that these bacterial strains are divided into two distinct groups at a level of similarity of 86 %. The SDS-PAGE was carried out to determine the profile of the total protein of the strains. The coefficients of similarity of polypeptide bands between the isolates and strains reference (Bradyrhizobium, Mesorizobium sp.) confirm that our strain belongs to the groups of rhizobia.

Keywords: SDS-PAGE, rhizobia, symbiosis, phenotypic characterization, Lablab purpureus

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1205 Patient Satisfaction Measurement Using Face-Q for Non-Incisional Double-Eyelid Blepharoplasty with Modified Single-Knot Continuous Buried Suture Technique

Authors: Kwei Huan Liw, Sashi B. Darshan

Abstract:

Background: Double eyelid surgery has become one of the most sought-after aesthetic procedures among Asians. Many surgeons perform surgical blepharoplasty and various other methods of non-incisional blepharoplasty. Face-Q is a validated method of measuring patient satisfaction for facial aesthetic procedures. Here we have analyzed the overall eye satisfaction score, the upper eyelid appraisal score and the adverse effect on eyes score Methods: 274 patients (548 eyes), aged between 18 to 40 years old, were recruited from 2015-2018. Each patient underwent a non-incisional double-eyelid blepharoplasty using a single-knotted continuous buried suture. 3 – 5 stab incisions were made depending on the upper eyelid size. A needle loaded with 7-0 nylon is passed from the lateral most wound through the dermis and the conjunctiva in an alternate fashion into the remaining stab wounds. The suture is then tunneled back laterally in the deeper dermis and knotted securely with the suture end. The knot is then buried within the orbicularis oculi muscle. Each patient was required to fill the Face-Q questionnaire before the procedure and 2 weeks post procedure. The results are described based on the percentage of the maximum achievable score. Patients were reviewed after 12 to 18 months to assess the long-term outcome. Results: The overall eye satisfaction score demonstrated a high level of post-operative satisfaction (97.85%), compared to 27.32% pre-operatively. The appraisal of upper eyelid scores showed drastic improvement in perception post-operatively (95.31%) compared to 21.44% pre-operatively. Adverse effect on eyes score showed a very low post-operative complication rate (0.4%) The long-term follow-up showed 6 cases that had developed asymmetrical folds. Only 1 patient agreed for revision surgery. The other 5 patients were still satisfied with the outcome and were not keen for revision surgery. None of the cases had loosening of knots. Conclusion: Modified single-knot continuous buried suture technique is a simple and non-invasive method to create aesthetically pleasing non-surgical double-eyelids, which has long-term effects. Proper patient selection is crucial and good surgical technique is required to achieve a desirable outcome.

Keywords: blepharoplasty, double-eyelid, face-Q, non-incisional

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1204 Applying Sociometer Theory to Different Age Groups and Groups Differences regarding State Self-Esteem Sensitivity

Authors: Yun Yu Stephanie Law

Abstract:

Sociometer Theory is well tested among young adults in western population, however, limited research is found for other age groups, like adolescent and middle-adulthood in Asia population. Thus, one of the main purposes of this study is to verify the validity of Sociometer Theory in different age groups among Asian. To be specific, we hypothesized that an increase in one’s perceived social rejection is associated to a decrease in his/her state self-esteem among all age groups in Asian population. And we expected that this association can be found among all age groups including adolescent, young adults and middle-adults group in our first study. In this way, we can verify the validity of Sociometer Theory across different age groups as well as its significance in Asian population. Furthermore, those participants who received rejection about ‘mate-role’ would also receive some negative feedbacks regarding their current/future capacity of being a good mate. Results suggested that participants’ state self-esteem sensitivity for mating-capacity rejection is higher when comparing to that of friend-capacity rejection, i.e. greater drop in state self-esteem when receiving mating-capacity feedbacks then receiving friend-capacity feedbacks. These results, however, is just applicable on young adults. Thus, the main purpose of study two would be testing the state self-esteem sensitivity towards social rejection in different domains among three age groups. We hypothesized that group differences would be found for three age groups regarding state self-esteem sensitivity. Research question 1: perceived social rejection is associated to decrease in state self-esteem, is applicable among different age groups in Asia population. Research question 2: there are significant group differences for three age groups regarding state self-esteem sensitivity. Methods: 300 subjects are divided into three age groups, adolescents group, young adult group and middle-adult group, with 100 subjects in each group. Two questionnaires were used in testing this fundamental concept. Subjects were then asked to rate themselves on questionnaire in measuring their current state self-esteem in order to obtain the baseline measurements for later comparison. In order to avoid demand characteristics from subjects, other unrelated tasks like word matching were also given after the first test. Results: A positive correlation between scores in questionnaire 1 and questionnaire 2 among all age groups. Conclusion: State self-esteem decrease to both imagined social rejection (study1) and experienced social rejection (study2). Moreover, level of decrease in state self-esteem vary when receiving different domains of social rejection. Implications: a better understanding of self-esteem development for various age group might bring insights for education systems and policies for teaching approaches and learning methods among different age groups.

Keywords: state self-esteem, social rejection, stage theory, self-feelings

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1203 Modeling Water Inequality and Water Security: The Role of Water Governance

Authors: Pius Babuna, Xiaohua Yang, Roberto Xavier Supe Tulcan, Bian Dehui, Mohammed Takase, Bismarck Yelfogle Guba, Chuanliang Han, Doris Abra Awudi, Meishui Lia

Abstract:

Water inequality, water security, and water governance are fundamental parameters that affect the sustainable use of water resources. Through policy formulation and decision-making, water governance determines both water security and water inequality. Largely, where water inequality exists, water security is undermined through unsustainable water use practices that lead to pollution of water resources, conflicts, hoarding of water, and poor sanitation. Incidentally, the interconnectedness of water governance, water inequality, and water security has not been investigated previously. This study modified the Gini coefficient and used a Logistics Growth of Water Resources (LGWR) Model to access water inequality and water security mathematically, and discussed the connected role of water governance. We tested the validity of both models by calculating the actual water inequality and water security of Ghana. We also discussed the implications of water inequality on water security and the overarching role of water governance. The results show that regional water inequality is widespread in some parts. The Volta region showed the highest water inequality (Gini index of 0.58), while the central region showed the lowest (Gini index of 0.15). Water security is moderately sustainable. The use of water resources is currently stress-free. It was estimated to maintain such status until 2132 ± 18, when Ghana will consume half of the current total water resources of 53.2 billion cubic meters. Effectively, water inequality is a threat to water security, results in poverty, under-development heightens tensions in water use, and causes instability. With proper water governance, water inequality can be eliminated through formulating and implementing approaches that engender equal allocation and sustainable use of water resources.

Keywords: water inequality, water security, water governance, Gini coefficient, moran index, water resources management

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1202 Probabilistic Fracture Evaluation of Reactor Pressure Vessel Subjected to Pressurized Thermal Shock

Authors: Jianguo Chen, Fenggang Zang, Yu Yang, Liangang Zheng

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Reactor Pressure Vessel (RPV) is an important security barrier in nuclear power plant. Crack like defects may be produced on RPV during the whole operation lifetime due to the harsh operation condition and irradiation embrittlement. During the severe loss of coolant accident, thermal shock happened as the injection of emergency cooling water into RPV, which results in re-pressurization of the vessel and very high tension stress on the vessel wall, this event called Pressurized Thermal Shock (PTS). Crack on the vessel wall may propagate even penetrate the vessel, so the safety of the RPV would undergo great challenge. Many assumptions in structure integrity evaluation make the result of deterministic fracture mechanics very conservative, which affect the operation lifetime of the plant. Actually, many parameters in the evaluation process, such as fracture toughness and nil-ductility transition temperature, have statistical distribution characteristics. So it is necessary to assess the structural integrity of RPV subjected to PTS event by means of Probabilistic Fracture Mechanics (PFM). Structure integrity evaluation methods of RPV subjected to PTS event are summarized firstly, then evaluation method based on probabilistic fracture mechanics are presented by considering the probabilistic characteristics of material and structure parameters. A comprehensive analysis example is carried out at last. The results show that the probability of crack penetrates through wall increases gradually with the growth of fast neutron irradiation flux. The results give advice for reactor life extension.

Keywords: fracture toughness, integrity evaluation, pressurized thermal shock, probabilistic fracture mechanics, reactor pressure vessel

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1201 Resonant Auxetic Metamaterial for Automotive Applications in Vibration Isolation

Authors: Adrien Pyskir, Manuel Collet, Zoran Dimitrijevic, Claude-Henri Lamarque

Abstract:

During the last decades, great efforts have been made to reduce acoustic and vibrational disturbances in transportations, as it has become a key feature for comfort. Today, isolation and design have neutralized most of the troublesome vibrations, so that cars are quieter and more comfortable than ever. However, some problems remain unsolved, in particular concerning low-frequency isolation and the frequency-dependent stiffening of materials like rubber. To sum it up, a balance has to be found between a high static stiffness to sustain the vibration source’s mass, and low dynamic stiffness, as wideband as possible. Systems meeting these criteria are yet to be designed. We thus investigated solutions inspired by metamaterials to control efficiently low-frequency wave propagation. Structures exhibiting a negative Poisson ratio, also called auxetic structures, are known to influence the propagation of waves through beaming or damping. However, their stiffness can be quite peculiar as well, as they can present regions of zero stiffness on the stress-strain curve for compression. In addition, auxetic materials can be easily adapted in many ways, inducing great tuning potential. Using finite element software COMSOL Multiphysics, a resonant design has been tested through statics and dynamics simulations. These results are compared to experimental results. In particular, the bandgaps featured by these structures are analyzed as a function of design parameters. Great stiffness properties can be observed, including low-frequency dynamic stiffness loss and broadband transmission loss. Such features are very promising for practical isolation purpose, and we hope to adopt this kind of metamaterial into an effective industrial damper.

Keywords: auxetics, metamaterials, structural dynamics, vibration isolation

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1200 Collaboration with Governmental Stakeholders in Positioning Reputation on Value

Authors: Zeynep Genel

Abstract:

The concept of reputation in corporate development comes to the fore as one of the most frequently discussed topics in recent years. Many organizations, which make worldwide investments, make effort in order to adapt themselves to the topics within the scope of this concept and to promote the name of the organization through the values that might become prominent. The stakeholder groups are considered as the most important actors determining the reputation. Even, the effect of stakeholders is not evaluated as a direct factor; it is signed as indirect effects of their perception are a very strong on ultimate reputation. It is foreseen that the parallelism between the projected reputation and the perceived c reputation, which is established as a result of communication experiences perceived by the stakeholders, has an important effect on achieving these objectives. In assessing the efficiency of these efforts, the opinions of stakeholders are widely utilized. In other words, the projected reputation, in which the positive and/or negative reflections of corporate communication play effective role, is measured through how the stakeholders perceptively position the organization. From this perspective, it is thought that the interaction and cooperation of corporate communication professionals with different stakeholder groups during the reputation positioning efforts play significant role in achieving the targeted reputation or in sustainability of this value. The governmental stakeholders having intense communication with mass stakeholder groups are within the most effective stakeholder groups of organization. The most important reason of this is that the organizations, regarding which the governmental stakeholders have positive perception, inspire more confidence to the mass stakeholders. At this point, the organizations carrying out joint projects with governmental stakeholders in parallel with sustainable communication approach come to the fore as the organizations having strong reputation, whereas the reputation of organizations, which fall behind in this regard or which cannot establish the efficiency from this aspect, is thought to be perceived as weak. Similarly, the social responsibility campaigns, in which the governmental stakeholders are involved and which play efficient role in strengthening the reputation, are thought to draw more attention. From this perspective, the role and effect of governmental stakeholders on the reputation positioning is discussed in this study. In parallel with this objective, it is aimed to reveal perspectives of seven governmental stakeholders towards the cooperation in reputation positioning. The sample group representing the governmental stakeholders is examined under the lights of results obtained from in-depth interviews with the executives of different ministries. It is asserted that this study, which aims to express the importance of stakeholder participation in corporate reputation positioning especially in Turkey and the effective role of governmental stakeholders in strong reputation, might provide a new perspective on measuring the corporate reputation, as well as establishing an important source to contribute to the studies in both academic and practical domains.

Keywords: collaborative communications, reputation management, stakeholder engagement, ultimate reputation

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1199 Challenges Faced by the Visually Impaired Children and their Parents in Doing Homework Assignments Using Braille

Authors: Shazia Farooq Mirza

Abstract:

The purpose of this study was to explore the challenges faced by visually impaired children and their parents in doing homework assignments using Braille. This study had a quantitative approach and it was descriptive in nature. It took place in 6 public and special private schools of Lahore.177 visually impaired children of grades 4-10 and 153 parents of the visually impaired children were the volunteer participants of this study which were selected through a convenient sampling method. A survey method was adopted for the data collection. And for this purpose 2 self-developed validated questionnaires were used as instruments. The instruments were constructed by exploring the factors and sub-factors from the literature review. Thirty students with visual impairment and 30 parents of the students with visual impairment filled the questionnaires as a pilot study, and it ensured the reliability of the instruments. Data were analyzed using a statistical package of social sciences and it was completely interpreted. Findings revealed that the common challenges faced by the students with visual impairment were Physical Stress, Readiness, Braille Knowledge, Braille Skill and Communications. And the major challenges faced by the parents of the students with visual impairment were the Availability of the helping material, the Availability of the reading material, Braille Knowledge, Braille skills, School and family interactions, Behavior management and the Environment and equipment. Conclusions were drawn on the basis of the major findings. Future suggestions are given in light of the conclusions. This study will be beneficial for the children with visual impairment, the parents of the children with visual impairment, the special education teachers and for the policymakers of the special schools.

Keywords: challenges, visually impaired children, homework, parents, braille

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1198 Antioxidant Activity and Hepatoprotective Potential of Genista quadriflora Munby against Paracetamol-Induced Liver Injury

Authors: Nacera Baali, Zahia Belloum, Souad Ameddah, Fadila Benayache, Samir Benayache, Chantal Wrutniak-Cabello

Abstract:

Allurement of herbs as health beneficial foods and as a source material for the development of new drugs, has led to greater furtherance in the study of herbal medicines during recent years. In the present study, in vitro antioxidant, free radical scavenging capacity, and hepatoprotective activity of butanolic extract from Genista quadriflora Munby (G.quadriflora) were evaluated using established in vitro models such as DPPH radical and hydrogen peroxide radical scavenging activities and antilipidperoxidation ability. Interestingly, the extract showed considerable in vitro antioxidant and free radical scavenging activities in a dose-dependent manner when compared to the standard antioxidant which verified the presence of antioxidant compound in extract tested. The hepatoprotective potential of G.quadriflora extract was also evaluated in male Wistar rats against paracetamol (APAP) induced liver damage. Therapy of G.quadriflora showed the liver protective effect on biochemical and histopathological alterations. Moreover, histological studies also supported the biochemical finding, that is, the maximum improvement in the histoarchitecture of the liver. Results revealed that G.quadriflora extract could protect the liver against APAP-induced oxidative damage by possibly increasing the antioxidant protection mechanism in rats. These findings are of great importance in view of the availability of the plant and its observed possible diverse applications in medicine and nutrition.

Keywords: genista quadriflora munby, antioxidant, liver, paracetamol, oxidative stress

Procedia PDF Downloads 473