Search results for: electronic measurement systems
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12994

Search results for: electronic measurement systems

6754 Innovative Screening Tool Based on Physical Properties of Blood

Authors: Basant Singh Sikarwar, Mukesh Roy, Ayush Goyal, Priya Ranjan

Abstract:

This work combines two bodies of knowledge which includes biomedical basis of blood stain formation and fluid communities’ wisdom that such formation of blood stain depends heavily on physical properties. Moreover biomedical research tells that different patterns in stains of blood are robust indicator of blood donor’s health or lack thereof. Based on these valuable insights an innovative screening tool is proposed which can act as an aide in the diagnosis of diseases such Anemia, Hyperlipidaemia, Tuberculosis, Blood cancer, Leukemia, Malaria etc., with enhanced confidence in the proposed analysis. To realize this powerful technique, simple, robust and low-cost micro-fluidic devices, a micro-capillary viscometer and a pendant drop tensiometer are designed and proposed to be fabricated to measure the viscosity, surface tension and wettability of various blood samples. Once prognosis and diagnosis data has been generated, automated linear and nonlinear classifiers have been applied into the automated reasoning and presentation of results. A support vector machine (SVM) classifies data on a linear fashion. Discriminant analysis and nonlinear embedding’s are coupled with nonlinear manifold detection in data and detected decisions are made accordingly. In this way, physical properties can be used, using linear and non-linear classification techniques, for screening of various diseases in humans and cattle. Experiments are carried out to validate the physical properties measurement devices. This framework can be further developed towards a real life portable disease screening cum diagnostics tool. Small-scale production of screening cum diagnostic devices is proposed to carry out independent test.

Keywords: blood, physical properties, diagnostic, nonlinear, classifier, device, surface tension, viscosity, wettability

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6753 Unveiling the Reaction Mechanism of N-Nitroso Dimethyl Amine Formation from Substituted Hydrazine Derivatives During Ozonation: A Computational Study

Authors: Rehin Sulay, Anandhu Krishna, Jintumol Mathew, Vibin Ipe Thomas

Abstract:

N-Nitrosodimethyl amine, the simplest member of the N-Nitrosoamine family, is a carcinogenic and mutagenic agent that has gained considerable research interest owing to its toxic nature. Ozonation of industrially important hydrazines such as unsymmetrical dimethylhydrazine (UDMH) or monomethylhydrazine (MMH) has been associated with NDMA formation and accumulation in the environment. UDMH/MMH - ozonation also leads to several other transformation products such as acetaldehyde dimethyl hydrazone (ADMH), tetramethyl tetra azene (TMT), diazomethane, methyl diazene, etc, which can be either precursors or competitors for NDMA formation.In this work, we explored the formation mechanism of ADMH and TMT from UDMH-ozonation and their further oxidation to NDMA using the second-order Moller Plesset perturbation theory employing the 6-311G(d) basis set. We have also investigated how MMH selectively forms methyl diazene and diazomethane under normal conditions and NDMA in the presence of excess ozone. Our calculations indicate that the reactions proceed via an initial H abstraction from the hydrazine –NH2 group followed by the oxidation of the generated N-radical species. The formation of ADMH from the UDMH-ozone reaction involves an acetaldehyde intermediate, which then reacts with a second UDMH molecule to generate ADMH. The preferable attack of ozone molecule on N=C bond of ADMH generates DMAN intermediate, which subsequently undergoes oxidation to form NDMA. Unlike other transformation products, TMT formation occurs via the dimerization of DMAN. Though there exist a N=N bonds in the TMT, which are preferable attacking sites for ozone, experimental studies show the lower yields of NDMA formation, which corroborates with the high activation barrier required for the process(42kcal/mol).Overall, our calculated results agree well with the experimental observations and rate constants. Computational calculations bring insights into the electronic nature and kinetics of the elementary reactions of this pathway, enabled by computed energies of structures that are not possible to access experimentally.

Keywords: reaction mechanism, ozonation, substituted hydrazine, transition state

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6752 Management of Acute Biliary Pathology at Gozo General Hospital

Authors: Kristian Bugeja, Upeshala A. Jayawardena, Clarissa Fenech, Mark Zammit Vincenti

Abstract:

Introduction: Biliary colic, acute cholecystitis, and gallstone pancreatitis are some of the most common surgical presentations at Gozo General Hospital (GGH). National Institute for Health and Care Excellence (NICE) guidelines advise that suitable patients with acute biliary problems should be offered a laparoscopic cholecystectomy within one week of diagnosis. There has traditionally been difficulty in achieving this mainly due to the reluctance of some surgeons to operate in the acute setting, limited, timely access to MRCP and ERCP, and organizational issues. Methodology: A retrospective study was performed involving all biliary pathology-related admissions to GGH during the two-year period of 2019 and 2020. Patients’ files and electronic case summary (ECS) were used for data collection, which included demographic data, primary diagnosis, co-morbidities, management, waiting time to surgery, length of stay, readmissions, and reason for readmissions. NICE clinical guidance 188 – Gallstone disease were used as the standard. Results: 51 patients were included in the study. The mean age was 58 years, and 35 (68.6%) were female. The main diagnoses on admission were biliary colic in 31 (60.8%), acute cholecystitis in 10 (19.6%). Others included gallstone pancreatitis in 3 (5.89%), chronic cholecystitis in 2 (3.92%), gall bladder malignancy in 4 (7.84%), and ascending cholangitis in 1 (1.97%). Management included laparoscopic cholecystectomy in 34 (66.7%); conservative in 8 (15.7%) and ERCP in 6 (11.7%). The mean waiting time for laparoscopic cholecystectomy for patients with acute cholecystitis was 74 days – range being between 3 and 146 days since the date of diagnosis. Only one patient who was diagnosed with acute cholecystitis and managed with laparoscopic cholecystectomy was done so within the 7-day time frame. Hospital re-admissions were reported in 5 patients (9.8%) due to vomiting (1), ascending cholangitis (1), and gallstone pancreatitis (3). Discussion: Guidelines were not met for patients presenting to Gozo General Hospital with acute biliary pathology. This resulted in 5 patients being re-admitted to hospital while waiting for definitive surgery. The local issues resulting in the delay to surgery need to be identified and steps are taken to facilitate the provision of urgent cholecystectomy for suitable patients.

Keywords: biliary colic, acute cholecystits, laparoscopic cholecystectomy, conservative management

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6751 The Impact of Green Building Envelopes on the Urban Microclimate of the Urban Canopy-Case Study: Fawzy Moaz Street, Alexandria, Egypt

Authors: Amany Haridy, Ahmed Elseragy, Fahd Omar

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The issue of temperature increase in the urban microclimate has been at the center of attention recently, especially in dense urban areas, such as the City of Alexandria in Egypt, where building surfaces have become the dominant element (more than green areas and streets). Temperatures have been rising during daytime as well as nighttime, however, the research focused on the rise of air temperature at night, a phenomenon known as the urban heat island. This phenomenon has many effects on ecological life, as well as human health. This study provided evidence of the possibility of reducing the urban heat island by using a green building envelope (green wall and green roof) in Alexandria, Egypt. This City has witnessed a boom in growth in its urban fabric and population. A simulation analysis using the Envi-met software to find the ratio of air temperature reduction was performed. The simulation depended on the orientation of the green areas and their density, which was defined through a process of climatic analysis made by the Diva plugin using the Grasshopper software. Results showed that the reduction in air temperature varies from 0.8–2.0 °C, increasing with the increasing density of green areas. Many systems of green wall and green roof can be found in the local market. However, treating an existing building requires a careful choice of system to fit the building construction load and the surrounding nature. Among the systems of choice, there was the ‘geometric system’ of vertical greening that can be fixed on a light aluminum structure for walls and the extensive green system for roofs. Finally, native plants were the best choice in the long term because they fare well in the local climate.

Keywords: envi-met, green building envelope, urban heat island, urban microclimate

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6750 Low-Surface Roughness and High Optical Quality CdS Thin Film Deposited on Heated Substrate Using Room-Temperature Chemical Solution

Authors: A. Elsayed, M. H. Dewaidar, M. Ghali, M. Elkemary

Abstract:

The high production cost of the conventional solar cells requires the search for economic methods suitable for solar energy conversion. Cadmium Sulfide (CdS) is one of the most important semiconductors used in photovoltaics, especially in large area solar cells; and can be prepared in a thin film form by a wide variety of deposition techniques. The preparation techniques include vacuum evaporation, sputtering and molecular beam epitaxy. Other techniques, based on chemical solutions, are also used for depositing CdS films with dramatically low-cost compared to other vacuum-based methods. Although this technique is widely used during the last decades, due to simplicity and low-deposition temperature (~100°C), there is still a strong need for more information on the growth process and its relation with the quality of the deposited films. Here, we report on deposition of high-quality CdS thin films; with low-surface roughness ( < 3.0 nm) and sharp optical absorption edge; on low-temperature glass substrates (70°C) using a new method based on the room-temperature chemical solution. In this method, a mixture solution of cadmium acetate and thiourea at room temperature was used under special growth conditions for deposition of CdS films. X-ray diffraction (XRD) measurements were used to examine the crystal structure properties of the deposited CdS films. In addition, UV-VIS transmittance and low-temperature (4K) photoluminescence (PL) measurements were performed for quantifying optical properties of the deposited films. The deposited films show high optical quality as confirmed by observation of both, sharp edge in the transmittance spectra and strong PL intensity at room temperature. Furthermore, we found a strong effect of the growth conditions on the optical band gap of the deposited films; where remarkable red-shift in the absorption edge with temperature is clearly seen in both transmission and PL spectra. Such tuning of both optical band gap of the deposited CdS films can be utilized for tuning the electronic bands' alignments between CdS and other light-harvesting materials, like CuInGaSe or CdTe, for potential improvement in the efficiency of solar cells devices based on these heterostructures.

Keywords: chemical deposition, CdS, optical properties, surface, thin film

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6749 Diabetes Care in Detention Settings: A Systematic Review

Authors: A. Papachristou, A. Ntikoudi, L. Makris, V. Saridakis

Abstract:

Introduction: More than 10 million people are imprisoned or detained worldwide. Figures from 2011-12 show that prison inmates are more likely than the general population to suffer from chronic or infectious diseases, while most inmates are overweight or obese, and more than a quarter have high blood pressure. In 2011/12, the proportion of prisoners reporting diabetes or hyperglycemia was 899 per 10,000 prisoners, almost double the 2004 figure (483 per 10,000). It is important to ensure that this population has access to the same standard of care as people outside prisons, as access to services should be need-based. Diabetes is a public health problem associated with increased morbidity and mortality worldwide. According to the International Diabetes Federation (IDF) in 2017, approximately 425 million people worldwide had diabetes. This number is expected to increase to 629 million by 2045. Poor management of diabetes in prisons can lead to poor blood sugar control and increase the risk of complications. Aim: The aim of this review was to systematically evaluate all the available literature on diabetes care in custodial settings. Methods: An extensive literature search was conducted through electronic databases (PubMed, Scopus and CINAHL) with the terms ‘custody’, ‘diabetes Mellitus, ‘detention centers and ‘chronic disease’. Articles published in English until September 2022, were included; no other criteria on publication dates were set. Results: Most of the studies mentioned a diabetes prevalence of approximately 10%, among other common chronic. Hypertension, obesity, smoking, sedentary lifestyle were the most common comorbidities associated with diabetes. Conclusion: Good glycemic control is fundamental to managing diabetes, and while many prisoners enter prison poorly, access to regular medication and meals, as well as exercise, offers the potential for improvement. Not being able to get help as quickly as in the past can be extremely stressful, and some prisoners may deliberately raise their blood sugar levels to avoid the risk of developing hypoglycemia, especially if they know they have had previous episodes of nocturnal hypoglycemia. Thus, appropriate training and resources are critical to providing quality care to incarcerated people with diabetes.

Keywords: custody, diabetes mellitus, detention centers, chronic disease

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6748 The Adoption of Leagility in Healthcare Services

Authors: Ana L. Martins, Luis Orfão

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Healthcare systems have been subject to various research efforts aiming at process improvement under a lean approach. Another perspective, agility, has also been used, though in a lower scale, in order to analyse the ability of different hospital services to adapt to demand uncertainties. Both perspectives have a common denominator, the improvement of effectiveness and efficiency of the services in a healthcare setting context. Mixing the two approached allows, on one hand, to streamline the processes, and on the other hand the required flexibility to deal with demand uncertainty in terms of both volume and variety. The present research aims to analyse the impacts of the combination of both perspectives in the effectiveness and efficiency of an hospital service. The adopted methodology is based on a case study approach applied to the process of the ambulatory surgery service of Hospital de Lamego. Data was collected from direct observations, formal interviews and informal conversations. The analyzed process was selected according to three criteria: relevance of the process to the hospital, presence of human resources, and presence of waste. The customer of the process was identified as well as his perception of value. The process was mapped using flow chart, on a process modeling perspective, as well as through the use of Value Stream Mapping (VSM) and Process Activity Mapping. The Spaghetti Diagram was also used to assess flow intensity. The use of the lean tools enabled the identification of three main types of waste: movement, resource inefficiencies and process inefficiencies. From the use of the lean tools improvement suggestions were produced. The results point out that leagility cannot be applied to the process, but the application of lean and agility in specific areas of the process would bring benefits in both efficiency and effectiveness, and contribute to value creation if improvements are introduced in hospital’s human resources and facilities management.

Keywords: case study, healthcare systems, leagility, lean management

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6747 Security Model for RFID Systems

Authors: John Ayoade

Abstract:

Radio Frequency Identification (RFID) has gained a lot of popularity in all walks of life due to its usefulness and diverse use of the technology in almost every application. However, there have been some security concerns most especially in regards to how authentic readers and tags can confirm their authenticity before confidential data is exchanged between them. In this paper, Kerberos protocol is adopted for the mutual authentication of RFID system components in order to ensure the secure communication between those components and to realize the authenticity of the communicating components.

Keywords: RFID, security, mutual authentication, Kerberos

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6746 Biodiversity Interactions Between C3 and C4 Plants under Agroforestry Cropping System

Authors: Ezzat Abd El Lateef

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Agroforestry means combining the management of trees with productive agricultural activities, especially in semiarid regions where crop yield increases are limited in agroforestry systems due to the fertility and microclimate improvements and the large competitive effect of trees with crops for water and nutrients, in order to assess the effect of agroforestry of some field crops with citrus trees as an approach to establish biodiversity in fruit tree plantations. Three field crops, i.e., maize, soybean and sunflower, were inter-planted with seedless orange trees (4*4 m) or were planted as solid plantings. The results for the trees indicated a larger fruit yield was obtained when soybean and sunflowers were interplant with citrus. Statistically significant effects (P<0.05) were found for maize grain and biological yields, with increased yields when grown as solid planting. There were no differences in the yields of soya bean and sunflower, where the yields were very similar between the two cropping systems. It is evident from the trials that agroforestry is an efficient concept to increase biodiversity through the interaction of trees with the interplant field crop species. Maize, unlike the other crops, was more sensitive to shade conditions under agroforestry practice and not preferred in the biodiversity system. The potential of agroforestry to improve or increase biodiversity is efficient as the understorey crops are usually C4 species, and the overstorey trees are invariably C3 species in agroforestry. Improvement in interplant species is most likely if the understorey crop is a C3 species, which are usually light saturated in the open, and partial shade may have little effect on assimilation or by a concurrent reduction in transpiration. It could be concluded that agroforestry is an efficient concept to increase biodiversity through the interaction of trees with the interplant field crop species. Some field crops could be employed successfully, like soybean or sunflowers, while others like maize are sensitive to incorporate in agroforestry system.

Keywords: agroforestry, field crops, C3 and C4 plants, yield

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6745 Quantification of the Erosion Effect on Small Caliber Guns: Experimental and Numerical Analysis

Authors: Dhouibi Mohamed, Stirbu Bogdan, Chabotier André, Pirlot Marc

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Effects of erosion and wear on the performance of small caliber guns have been analyzed throughout numerical and experimental studies. Mainly, qualitative observations were performed. Correlations between the volume change of the chamber and the maximum pressure are limited. This paper focuses on the development of a numerical model to predict the maximum pressure evolution when the interior shape of the chamber changes in the different weapon’s life phases. To fulfill this goal, an experimental campaign, followed by a numerical simulation study, is carried out. Two test barrels, « 5.56x45mm NATO » and « 7.62x51mm NATO,» are considered. First, a Coordinate Measuring Machine (CMM) with a contact scanning probe is used to measure the interior profile of the barrels after each 300-shots cycle until their worn out. Simultaneously, the EPVAT (Electronic Pressure Velocity and Action Time) method with a special WEIBEL radar are used to measure: (i) the chamber pressure, (ii) the action time, (iii) and the bullet velocity in each barrel. Second, a numerical simulation study is carried out. Thus, a coupled interior ballistic model is developed using the dynamic finite element program LS-DYNA. In this work, two different models are elaborated: (i) coupled Eularien Lagrangian method using fluid-structure interaction (FSI) techniques and a coupled thermo-mechanical finite element using a lumped parameter model (LPM) as a subroutine. Those numerical models are validated and checked through three experimental results, such as (i) the muzzle velocity, (ii) the chamber pressure, and (iii) the surface morphology of fired projectiles. Results show a good agreement between experiments and numerical simulations. Next, a comparison between the two models is conducted. The projectile motions, the dynamic engraving resistances and the maximum pressures are compared and analyzed. Finally, using this obtained database, a statistical correlation between the muzzle velocity, the maximum pressure and the chamber volume is established.

Keywords: engraving process, finite element analysis, gun barrel erosion, interior ballistics, statistical correlation

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6744 An Elaborated Software Solution: The Tennis Ranking System

Authors: Dionysios Kakaroumpas, Jesseka Farago, Stephen Webber

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Athletes and spectators depend on the tennis ranking system to represent the truest caliber of athletic prowess; a careful look at the current ranking system though, reveals its main weakness: it undermines expectations of fans and players. Our study proposes several key changes to the existing ranking formula that provide a fair and accurate approach to measure player performance. The study proposes a modification of the system to value: participation, continued advancement, and overall achievement. The new ranking formula facilitates closing the trust gap, encouraging competition equality, engaging the fan base, attracting investment, and promoting tennis involvement worldwide. To probe the crux of our main contention we performed week-by-week comparisons between results procured from the current and proposed formulae. After performing this rigorous case-study of top players of each gender, the findings strongly indicated that there is identifiable inflation in the ranks and enhanced the conviction that the current system should be updated. The new system is accompanied by a web-based software package freely available to anyone involved or interested in tennis rankings. The software package is designed to automatically calculate new player rankings based on a responsive, multi-faceted formula that also generates projected point scenarios and provides separate rankings for the three different court surfaces. By taking a critical look at the current tennis ranking system with consideration to the perspective of fans, players, and businesses involved, an upgrade is in order for it to maintain the balance of trust between fans and the evaluation process. In closure, this proposed solution increases fair play competition, eliminates rank inflation, and better engages fans, players, and sponsors by bringing in a new era of professional tennis.

Keywords: measurement and evaluation, rules and regulations, sports management and marketing, tennis ranking system

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6743 Correlation between Flexible Flatfoot and Lumbosacral Angle

Authors: Moustafa Elwan, Sohier Shehata, Fatma Sedek, Manar Hussine

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One of the most risky factors that lead to a foot injury during physical activities are both high and low arched feet. Normally the medial longitudinal arch of the foot develops in the first 10 years of life, so flexible flat foot has an inversely relationship with age in the first decade, all over the world, the prevalence of flat foot is increasing. In approximately 15% of foot deformities cases, the deformity does not disappear and remains throughout adulthood, 90% of the clinical cases are complaining from foot problems are due to flatfoot. Flatfoot creates subtalar over pronation, which creates tibial and femoral medial rotation, and that is accompanied with increases of pelvic tilting anteriorly, which may influence the lumbar vertebrae alignment by increasing muscle tension and rotation. Objective: To study the impact of the flexible flatfoot on lumbosacral angle (angle of Ferguson). Methods: This experiment included 40 volunteers (14 females &26 males) gathered from the Faculty of Physical Therapy, Modern University of Technology and Information, Cairo, Egypt, for each participant, four angles were measured in the foot( talar first metatarsal angle, lateral talocalcaneal angle, , Calcaneal first metatarsal angle, calcaneal inclination angle) and one angle in the lumbar region (lumbosacral angle). Measurement of these angles was conducted by using Surgimap Spine software (version 2.2.9.6). Results: The results demonstrated that there was no significant correlation betweenFerguson angle and lateral talocalcaneal (r=0.164, p=0.313). Also, there was no significant correlation between Ferguson angle and talo first metatarsal “Meary’s angle" (r=0.007, p=0.968). Moreover, there was no significant correlation between Ferguson angle and calcaneal-first metatarsal angle (r=0.083, p=0.612). Also, there was no significant correlation between Ferguson angle and calcaneal inclination angle (r= 0.032, p= 0.846). Conclusion: It can be concluded that there is no significant correlation between the flexible flat foot and lumbosacral angle So, more study should be conducted in large sample and different ages and conditions of foot problems.

Keywords: calcaneal first metatarsal, calcaneal inclination, flatfoot, ferguson’s angle, lateral talocalcaneal angle, lumbosacral angle, and talar first metatarsal angle

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6742 Performance Evaluation of GPS/INS Main Integration Approach

Authors: Othman Maklouf, Ahmed Adwaib

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This paper introduces a comparative study between the main GPS/INS coupling schemes, this will include the loosely coupled and tightly coupled configurations, several types of situations and operational conditions, in which the data fusion process is done using Kalman filtering. This will include the importance of sensors calibration as well as the alignment of the strap down inertial navigation system. The limitations of the inertial navigation systems are investigated.

Keywords: GPS, INS, Kalman filter, sensor calibration, navigation system

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6741 Ethnic Andean Concepts of Health and Illness in the Post-Colombian World and Its Relevance Today

Authors: Elizabeth J. Currie, Fernando Ortega Perez

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—‘MEDICINE’ is a new project funded under the EC Horizon 2020 Marie-Sklodowska Curie Actions, to determine concepts of health and healing from a culturally specific indigenous context, using a framework of interdisciplinary methods which integrates archaeological-historical, ethnographic and modern health sciences approaches. The study will generate new theoretical and methodological approaches to model how peoples survive and adapt their traditional belief systems in a context of alien cultural impacts. In the immediate wake of the conquest of Peru by invading Spanish armies and ideology, native Andeans responded by forming the Taki Onkoy millenarian movement, which rejected European philosophical and ontological teachings, claiming “you make us sick”. The study explores how people’s experience of their world and their health beliefs within it, is fundamentally shaped by their inherent beliefs about the nature of being and identity in relation to the wider cosmos. Cultural and health belief systems and related rituals or behaviors sustain a people’s sense of identity, wellbeing and integrity. In the event of dislocation and persecution these may change into devolved forms, which eventually inter-relate with ‘modern’ biomedical systems of health in as yet unidentified ways. The development of new conceptual frameworks that model this process will greatly expand our understanding of how people survive and adapt in response to cultural trauma. It will also demonstrate the continuing role, relevance and use of TM in present-day indigenous communities. Studies will first be made of relevant pre-Colombian material culture, and then of early colonial period ethnohistorical texts which document the health beliefs and ritual practices still employed by indigenous Andean societies at the advent of the 17th century Jesuit campaigns of persecution - ‘Extirpación de las Idolatrías’. Core beliefs drawn from these baseline studies will then be used to construct a questionnaire about current health beliefs and practices to be taken into the study population of indigenous Quechua peoples in the northern Andean region of Ecuador. Their current systems of knowledge and medicine have evolved within complex historical contexts of both the conquest by invading Inca armies in the late 15th century, followed a generation later by Spain, into new forms. A new model will be developed of contemporary  Andean concepts of health, illness and healing demonstrating  the way these have changed through time. With this, a ‘policy tool’ will be constructed as a bridhging facility into contemporary global scenarios relevant to other Indigenous, First Nations, and migrant peoples to provide a means through which their traditional health beliefs and current needs may be more appropriately understood and met. This paper presents findings from the first analytical phases of the work based upon the study of the literature and the archaeological records. The study offers a novel perspective and methods in the development policies sensitive to indigenous and minority people’s health needs.

Keywords: Andean ethnomedicine, Andean health beliefs, health beliefs models, traditional medicine

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6740 Parent’s Expectations and School Achievement: Longitudinal Perspective among Chilean Pupils

Authors: Marine Hascoet, Valentina Giaconi, Ludivine Jamain

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The aim of our study is to examine if the family socio-economic status (SES) has an influence on students’ academic achievement. We first make the hypothesis that the more their families have financial and social resources, the more students succeed at school. We second make the hypothesis that this family SES has also an impact on parents’ expectations about their children educational outcomes. Moreover, we want to study if that parents’ expectations play the role of mediator between parents’ socio-economic status and the student’ self-concept and academic outcome. We test this model with a longitudinal design thanks to the census-based assessment from the System of Measurement of the Quality of Education (SIMCE). The SIMCE tests aim to assess all the students attending to regular education in a defined level. The sample used in this study came from the SIMCE assessments done three times: in 4th, 8th and 11th grade during the years 2007, 2011 and 2014 respectively. It includes 156.619 students (75.084 boys and 81.535 girls) that had valid responses for the three years. The family socio-economic status was measured at the first assessment (in 4th grade). The parents’ educational expectations and the students’ self-concept were measured at the second assessment (in 8th grade). The achievement score was measured twice; once when children were in 4th grade and a second time when they were in 11th grade. To test our hypothesis, we have defined a structural equation model. We found that our model fit well the data (CFI = 0.96, TLI = 0.95, RMSEA = 0.05, SRMR = 0.05). Both family SES and prior achievements predict parents’ educational expectations and effect of SES is important in comparison to the other coefficients. These expectations predict students’ achievement three years later (with prior achievement controlled) but not their self-concept. Our model explains 51.9% of the achievement in the 11th grade. Our results confirm the importance of the parents’ expectations and the significant role of socio-economic status in students’ academic achievement in Chile.

Keywords: Chilean context, parent’s expectations, school achievement, self-concept, socio-economic status

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6739 Comparative Evaluation of Pentazocine and Tramadol as Pre-Emptive Analgesics for Ovariohysterectomy in Female Dogs

Authors: Venkatgiri, Ranganath, L. Nagaraja, B. N. Sagar Pandav, S. M. Usturge, D. Dilipkumar, B. V. Shivprakash, B. Bhagwanthappa, D. Jahangir

Abstract:

A comparative evaluation of Tramadol and Pentazocine as a pre-emptive analgesic in clinical cases of female dogs undergoing ovariohysterectomy was undertaken during this study. During the study, the following parameters were assessed viz., Rectal temperature (ᵒF), Respiratory rate (breaths/min) and Heart rate (beats/min). Hematological and biochemical parameters viz., total erythrocyte count (TEC) (millions/cmm), hemoglobin (g %), otal leucocytes count (TLC) (thousands/cmm), differential leucocytes count (DLC) (%), serum creatinine (mg/dl), plasma protein (mg/dl), blood glucose (mg/dl) was estimated before the surgery and after administration of general anaesthesia and immediate postoperative periods of 0, 12 and 24 hr respectively. Mean Total Pain Score (MTPS) includes measurement of parameters like posture, vocalization, activity level, response to palpation and agitation at different intervals was calculated before surgery and after administration of general anesthesia and post-operative periods of 1, 2, 4, 6, 12hrs and 24 hrs respectively. Mean Total Pain Score (MTPS) was given for each parameter (Posture, Vocalization, Activity Level, Response to Palpation and Agitation) like 0,1,2,3. (maximum score will be given was 4.). Results were revealed in all three groups including control group. There were significant minor alterations in physiological, hematological and biochemical parameters. MTPS (mean total pain score) were revealed and found a significant alteration when compared with control group. In conclusion, Tramadol found to be a better analgesic and had up to 8hrs of analgesic effect and Pentazocine is superior in post-operative pain management when compared to Tramadol because this group of dogs experienced less surgical stress, consumed less anesthetic dose, they recovered early, and they had less MTPS score.

Keywords: dog, pentazocine, tramadol, ovariohysterectomy

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6738 Kinetics of Sugar Losses in Hot Water Blanching of Water Yam (Dioscorea alata)

Authors: Ayobami Solomon Popoola

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Yam is majorly a carbohydrate food grown in most parts of the world. It could be boiled, fried or roasted for consumption in a variety of ways. Blanching is an established heat pre-treatment given to fruits and vegetables prior to further processing such as dehydration, canning, freezing etc. Losses of soluble solids during blanching has been a great problem because a reasonable quantity of the water-soluble nutrients are inevitably leached into the blanching water. Without blanching, the high residual levels of reducing sugars after extended storage produce a dark, bitter-tasting product because of the Maillard reactions of reducing sugars at frying temperature. Measurement and prediction of such losses are necessary for economic efficiency in production and to establish the level of effluent treatment of the blanching water. This paper aims at resolving this problem by investigating the effects of cube size and temperature on the rate of diffusional losses of reducing sugars and total sugars during hot water blanching of water-yam. The study was carried out using four temperature levels (65, 70, 80 and 90 °C) and two cubes sizes (0.02 m³ and 0.03 m³) at 4 times intervals (5, 10, 15 and 20 mins) respectively. Obtained data were fitted into Fick’s non-steady equation from which diffusion coefficients (Da) were obtained. The Da values were subsequently fitted into Arrhenius plot to obtain activation energies (Ea-values) for diffusional losses. The diffusion co-efficient were independent of cube size and time but highly temperature dependent. The diffusion coefficients were ≥ 1.0 ×10⁻⁹ m²s⁻¹ for reducing sugars and ≥ 5.0 × 10⁻⁹ m²s⁻¹ for total sugars. The Ea values ranged between 68.2 to 73.9 KJmol⁻¹ and 7.2 to 14.30 KJmol⁻¹ for reducing sugars and total sugars losses respectively. Predictive equations for estimating amount of reducing sugars and total sugars with blanching time of water-yam at various temperatures were also presented. The equation could be valuable in process design and optimization. However, amount of other soluble solids that might have leached into the water along with reducing and total sugars during blanching was not investigated in the study.

Keywords: blanching, kinetics, sugar losses, water yam

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6737 Emerging Social Media Presence of International Organisations - Challenges and Opportunities

Authors: Laura Hervai

Abstract:

One of the most significant phenomena of the 2000s was the emergence of social media sites and web 2.0 that revolutionized communication processes. Social networking platforms have fundamentally changed social and political participation of the public, which require organisations in the public and non-profit sector not only to adapt to these new trends but also to actively engage their audiences. Opportunity for interaction, freer expression of opinion and the proliferation of user generated content are major changes brought by web 2.0 technologies. Furthermore, due to the wide penetration of mobile technologies, social media sites are capable of connecting underdeveloped regions to the global flow of information. Taking advantage of these characteristics, organisations have the opportunity to engage much wider audiences, exploit new ways to raise awareness or reach out to regions that are difficult to access. The early adopters of these new communication tools soon recognized the need of developing social media guidelines for their organisations as well as the increased workload that they require. While ten years ago communication officers could handle their organisation’s social media presence, today it is a separate profession. International organisations face several challenges related to their social media presence. Early adopters have contributed to the development of best practices among which the ethics of social media usage still remained problematic. Another challenge for international organisations is to adapt to country-specific social media trends while they have to comply with the requirements of their parent organisation as well. However in the 21st century social media presence can be crucial to the successful operation of international organisations, their importance is still not taken seriously enough. The measurement of the effects and influence of social networking on the organisations’ productivity is an unsolved problem thus further research should focus on this matter. Research methods included primary research of major IGOs’ and NGOs’ social media presence and guidelines along with secondary research of social media statistics and scientific articles in the topic.

Keywords: international organisations, non-profit sector, NGO, social media, social network

Procedia PDF Downloads 307
6736 Osteoporosis and Weight Gain – Two Major Concerns for Menopausal Women - a Physiotherapy Perspective

Authors: Renu Pattanshetty

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The aim of this narrative review is to highlight the impact of menopause on osteoporosis and weight gain. The review also aims to summarize physiotherapeutic strategies to combat the same.A thorough literature search was conducted using electronic databases like MEDline, PUBmed, Highwire Press, PUBmed Central for English language studies that included search terms like menopause, osteoporosis, obesity, weight gain, exercises, physical activity, physiotherapy strategies from the year 2000 till date. Out of 157 studies that included metanalyses, critical reviews and randomized clinical trials, a total of 84 were selected that met the inclusion criteria. Prevalence of obesity is increasing world - wide and is reaching epidemic proportions even in the menopausal women. Prevalence of abdominal obesity is almost double than that general obesity with rates in the US with 65.5% in women ages 40-59 years and 73.8 in women aged 60 years or more. Physical activities and exercises play a vital role in prevention and treatment of osteoporosis and weight gain related to menopause that aim to boost the general well-being and any symptoms brought about by natural body changes. Endurance exercises lasting about 30 minutes /day for 5 days/ week has shown to decrease weight and prevent weight gain. In addition, strength training with at least 8 exercises of 8-12 repetitions working for whole body and for large muscle groups has shown to result positive outcomes. Hot flashes can be combatted through yogic breathing and relaxation exercises. Prevention of fall strategies and resistance training are key to treat diagnosed cases of osteoporosis related to menopause. One to three sets with five to eight repetitions of four to six weight bearing exercises have shown positive results. Menopause marks an important time for women to evaluate their risk of obesity and osteoporosis. It is known fact that bone benefit from exercises are lost when training is stopped, hence, practicing bone smart habits and strict adherence to recommended physical activity programs are recommended which are enjoyable, safe and effective.

Keywords: menopause, osteoporosis, obesity, weight gain, exercises, physical activity, physiotherapy strategies

Procedia PDF Downloads 303
6735 Psychological Capital: Convergent and Discriminant Validity of a Reconfigured Measure

Authors: Anton Grobler

Abstract:

Background: Psychological capital (PsyCap), consisting of Hope, Optimism, Resilience, and Self-efficacy, is a popular positive organisational behaviour construct utilised in the studying employee work and behavioral attitudes. Various scholars believe however that further validity research should be conducted on the PsyCap questionnaire (PCQ), outside of the founding research team and in more diverse settings, for the purpose of this paper, within the diverse South African (SA) context. Aim: The purpose of this study was to investigate the construct validity of the PCQ with specific reference to its psychometric properties within the diverse SA context. Setting: The sample includes a total of 1 749 respondents, ± 60 each from 30 organisations in South Africa. Method: This study utilised a cross-sectional design and quantitative analysis. The sample is relatively representative (in terms of race, gender) of the South African workforce. A multi-factorial model was statistically explored and confirmed (with exploratory factor analysis [EFA] and confirmatory factor analysis [CFA] respectively). Results: The study yielded a three-factor solution, with Hope and Optimism as a combined factor and Resilience and Self-efficacy made up of a reconfigured set of substantively justifiable items. Three items of the original 24 items were found not to be suitable. The three factors showed good psychometric properties, good fit (in support of construct validity) and acceptable levels of convergent and discriminant validity. Conclusion: The results support the original conceptualisation of PsyCap, although with a unique structural configuration. This resonates with the notion of scholars that further research should be conducted within diverse settings. This is necessary to ensure the valid measurement of the construct, which is considered to be one of the four criteria for a construct to be categorised as a positive organisational behaviour construct.

Keywords: positive organisational behaviour, psychological capital, hope, optimism, resilience, self-efficacy, construct validity

Procedia PDF Downloads 198
6734 Application of Flory Paterson’s Theory on the Volumetric Properties of Liquid Mixtures: 1,2-Dichloroethane with Aliphatic and Cyclic Ethers

Authors: Linda Boussaid, Farid Brahim Belaribi

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The physico-chemical properties of liquid materials in the industrial field, in general, and in that of the chemical industries, in particular, constitutes a prerequisite for the design of equipment, for the resolution of specific problems (related to the techniques of purification and separation, at risk in the transport of certain materials, etc.) and, therefore, at the production stage. Chloroalkanes, ethers constitute three chemical families having an industrial, theoretical and environmental interest. For example, these compounds are used in various applications in the chemical and pharmaceutical industries. In addition, they contribute to the particular thermodynamic behavior (deviation from ideality, association, etc.) of certain mixtures which constitute a severe test for predictive theoretical models. Finally, due to the degradation of the environment in the world, a renewed interest is observed for ethers, because some of their physicochemical properties could contribute to lower pollution (ethers would be used as additives in aqueous fuels.). This work is a thermodynamic, experimental and theoretical study of the volumetric properties of liquid binary systems formed from compounds belonging to the chemical families of chloroalkanes, ethers, having an industrial, theoretical and environmental interest. Experimental determination of the densities and excess volumes of the systems studied, at different temperatures in the interval [278.15-333.15] K and at atmospheric pressure, using an AntonPaar vibrating tube densitometer of the DMA5000 type. This contribution of experimental data, on the volumetric properties of the binary liquid mixtures of 1,2-dichloroethane with an ether, supplemented by an application of the theoretical model of Prigogine-Flory-Patterson PFP, will probably contribute to the enrichment of the thermodynamic database and the further development of the theory of Flory in its Prigogine-Flory-Patterson (PFP) version, for a better understanding of the thermodynamic behavior of these liquid binary mixtures

Keywords: prigogine-flory-patterson (pfp), propriétés volumétrique , volume d’excés, ethers

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6733 Compensation of Bulk Charge Carriers in Bismuth Based Topological Insulators via Swift Heavy Ion Irradiation

Authors: Jyoti Yadav, Rini Singh, Anoop M.D, Nisha Yadav, N. Srinivasa Rao, Fouran Singh, Takayuki Ichikawa, Ankur Jain, Kamlendra Awasthi, Manoj Kumar

Abstract:

Nanocrystalline films exhibit defects and strain induced by its grain boundaries. Defects and strain affect the physical as well as topological insulating properties of the Bi2Te3 thin films by changing their electronic structure. In the present studies, the effect of Ni7+ ion irradiation on the physical and electrical properties of Bi2Te3 thin films was studied. The films were irradiated at five different fluences (5x1011, 1x1012, 3x1012, 5x1012, 1x1013 ions/cm2). Thin films synthesized using the e-beam technique possess a rhombohedral crystal structure with the R-3m space group. The average crystallite size, as determined by x-ray diffraction (XRD) peak broadening, was found to be 18.5 ± 5 (nm). It was also observed that irradiation increases the induced strain. Raman Spectra of the films demonstrate the splitting of A_1u^1 modes originating from the vibrations along the c-axis. This is by the variation in the lattice parameter ‘c,’ as observed through XRD. The atomic force microscopy study indicates the decrease in surface roughness up to the fluence of 3x1012 ions/cm2 and further increasing the fluence increases the roughness. The decrease in roughness may be due to the growth of smaller nano-crystallites on the surface of thin films due to irradiation-induced annealing. X-ray photoelectron spectroscopy studies reveal the composition to be in close agreement to the nominal values i.e. Bi2Te3. The resistivity v/s temperature measurements revealed an increase in resistivity up to the fluence 3x1012 ions/cm2 and a decrease on further increasing the fluence. The variation in electrical resistivity is corroborated with the change in the carrier concentration as studied through low-temperature Hall measurements. A crossover from the n-type to p-type carriers was achieved in the irradiated films. Interestingly, tuning of the Fermi level by compensating the bulk carriers using ion-irradiation could be achieved.

Keywords: Annealing, Irradiation, Fermi level, Tuning

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6732 In silico Analysis towards Identification of Host-Microbe Interactions for Inflammatory Bowel Disease Linked to Reactive Arthritis

Authors: Anukriti Verma, Bhawna Rathi, Shivani Sharda

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Reactive Arthritis (ReA) is a disorder that causes inflammation in joints due to certain infections at distant sites in the body. ReA begins with stiffness, pain, and inflammation in these areas especially the ankles, knees, and hips. It gradually causes several complications such as conjunctivitis in the eyes, skin lesions in hand, feet and nails and ulcers in the mouth. Nowadays the diagnosis of ReA is based upon a differential diagnosis pattern. The parameters for differentiating ReA from other similar disorders include physical examination, history of the patient and a high index of suspicion. There are no standard lab tests or markers available for ReA hence the early diagnosis of ReA becomes difficult and the chronicity of disease increases with time. It is reported that enteric disorders such as Inflammatory Bowel Disease (IBD) that is inflammation in gastrointestinal tract namely Crohn’s Disease (CD) and Ulcerative Colitis (UC) are reported to be linked with ReA. Several microorganisms are found such as Campylobacter, Salmonella, Shigella and Yersinia causing IBD leading to ReA. The aim of our study was to perform the in-silico analysis in order to find interactions between microorganisms and human host causing IBD leading to ReA. A systems biology approach for metabolic network reconstruction and simulation was used to find the essential genes of the reported microorganisms. Interactomics study was used to find the interactions between the pathogen genes and human host. Genes such as nhaA (pathogen), dpyD (human), nagK (human) and kynU (human) were obtained that were analysed further using the functional, pathway and network analysis. These genes can be used as putative drug targets and biomarkers in future for early diagnosis, prevention, and treatment of IBD leading to ReA.

Keywords: drug targets, inflammatory bowel disease, reactive arthritis, systems biology

Procedia PDF Downloads 275
6731 Some Issues with Extension of an HPC Cluster

Authors: Pil Seong Park

Abstract:

Homemade HPC clusters are widely used in many small labs, because they are easy to build and cost-effective. Even though incremental growth is an advantage of clusters, it results in heterogeneous systems anyhow. Instead of adding new nodes to the cluster, we can extend clusters to include some other Internet servers working independently on the same LAN, so that we can make use of their idle times, especially during the night. However extension across a firewall raises some security problems with NFS. In this paper, we propose a method to solve such a problem using SSH tunneling, and suggest a modified structure of the cluster that implements it.

Keywords: extension of HPC clusters, security, NFS, SSH tunneling

Procedia PDF Downloads 426
6730 Cloud Computing Impact on e-Government Adoption

Authors: Ali Elshabrawy

Abstract:

Cloud computing is expected to be important for e Government in near future. Governments need it for solving some of its e Government, financial, infrastructure, legacy systems and integration problems. It reduces information technology (IT) infrastructure needs and support costs, and offers on-demand infrastructure and computational power, improved collaboration capabilities, which are important for e Government projects start up and sustainability. Budget pressures will continue to drive more and more government IT to hybrid and even public clouds, and more cooperation between cloud service providers and governmental agencies are expected, Or developing governmental private, community clouds. Motivation to convince governments to use cloud computing services, will create a pressure on cloud service providers to cope with government's requirements for interoperability, security standards, open data and integration between their cloud systems There will be significant legal action arising out of governmental uses of cloud computing, and legislation addressing both IT and business needs and consumer fears and protections. Cloud computing is a considered a revolution for IT and E business in general and e commerce, e Government in particular. As governments faces increasing challenges regarding IT infrastructure required for e Government projects implementation. As a result of Lack of required financial resources allocated for e Government projects in developed and developing countries. Cloud computing can play a major role to solve some of e Government projects challenges such as, lack of financial resources, IT infrastructure, Human resources trained to manage e Government applications, interoperability, cost efficiency challenges. If we could solve some security issues related to cloud computing usage which considered critical for e Government projects. Pretty sure it’s Just a matter of time before cloud service providers will find out solutions to attract governments as major customers for their business.

Keywords: cloud computing, e-government, adoption, supply side barriers, e-government requirements, challenges

Procedia PDF Downloads 346
6729 The Solid-Phase Sensor Systems for Fluorescent and SERS-Recognition of Neurotransmitters for Their Visualization and Determination in Biomaterials

Authors: Irina Veselova, Maria Makedonskaya, Olga Eremina, Alexandr Sidorov, Eugene Goodilin, Tatyana Shekhovtsova

Abstract:

Such catecholamines as dopamine, norepinephrine, and epinephrine are the principal neurotransmitters in the sympathetic nervous system. Catecholamines and their metabolites are considered to be important markers of socially significant diseases such as atherosclerosis, diabetes, coronary heart disease, carcinogenesis, Alzheimer's and Parkinson's diseases. Currently, neurotransmitters can be studied via electrochemical and chromatographic techniques that allow their characterizing and quantification, although these techniques can only provide crude spatial information. Besides, the difficulty of catecholamine determination in biological materials is associated with their low normal concentrations (~ 1 nM) in biomaterials, which may become even one more order lower because of some disorders. In addition, in blood they are rapidly oxidized by monoaminooxidases from thrombocytes and, for this reason, the determination of neurotransmitter metabolism indicators in an organism should be very rapid (15—30 min), especially in critical states. Unfortunately, modern instrumental analysis does not offer a complex solution of this problem: despite its high sensitivity and selectivity, HPLC-MS cannot provide sufficiently rapid analysis, while enzymatic biosensors and immunoassays for the determination of the considered analytes lack sufficient sensitivity and reproducibility. Fluorescent and SERS-sensors remain a compelling technology for approaching the general problem of selective neurotransmitter detection. In recent years, a number of catecholamine sensors have been reported including RNA aptamers, fluorescent ribonucleopeptide (RNP) complexes, and boronic acid based synthetic receptors and the sensor operated in a turn-off mode. In this work we present the fluorescent and SERS turn-on sensor systems based on the bio- or chemorecognizing nanostructured films {chitosan/collagen-Tb/Eu/Cu-nanoparticles-indicator reagents} that provide the selective recognition, visualization, and sensing of the above mentioned catecholamines on the level of nanomolar concentrations in biomaterials (cell cultures, tissue etc.). We have (1) developed optically transparent porous films and gels of chitosan/collagen; (2) ensured functionalization of the surface by molecules-'recognizers' (by impregnation and immobilization of components of the indicator systems: biorecognizing and auxiliary reagents); (3) performed computer simulation for theoretical prediction and interpretation of some properties of the developed materials and obtained analytical signals in biomaterials. We are grateful for the financial support of this research from Russian Foundation for Basic Research (grants no. 15-03-05064 a, and 15-29-01330 ofi_m).

Keywords: biomaterials, fluorescent and SERS-recognition, neurotransmitters, solid-phase turn-on sensor system

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6728 How to Break an Outbreak: Containment Measures of a Salmonella Outbreak Associated with Egg Consumption

Authors: Gal Zagron, Nitza Abramson, Deena R. Zimmerman, Chen Stein-Zamir

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Background: Salmonella enteritidis is a common cause of foodborne outbreaks, primarily associated with poultry eggs. S. enteritidis This is the only Salmonella type that is found inside the eggshell. A rise in Salmonella enteritidis notifications was noted in spring 2017. Aims: The aim of this study is to describe the epidemiological investigation of the outbreak in the Jerusalem district, along with the containment measures taken. Methods: This study is a population-based epidemiological study with a description of environmental control activities. Results: During the months May - July, 2017 848 salmonellosis cases were reported to the Jerusalem district health office compared to 294 cases May - July 2016. Salmonella enteritidis was isolated in 58% of reported cases. Clusters and outbreaks ( > 2 cases) were reported among nursery schools, nursing homes, persons residing in one kibbutz and several cases in different food service establishments in the Jerusalem district. Epidemiological investigations revealed eggs consumption as a common feature among the cases (uncooked or undercooked eggs in most cases). A national investigation among egg suppliers revealed that most cases consumed eggs provided by a single provider with isolation of Salmonella enteritidis at the source as well. Containment measures were taken to control the epidemic including distributing information via electronic and written media to the public, searching for all egg distribution centers, informing local authorities, the poultry council and food stores. The eggs originating from the provider were recalled and extinguished. Written instructions to all food preparation facilities in the district were distributed regarding the proper storage and preparation of eggs. The number of reported cases declined and the outbreak vanished during correlating months of 2018. Conclusions: The investigation of Salmonella enteritidis outbreaks should include epidemiological and laboratory investigations, tracing the source of the eggs and testing the eggs and the source of eggs. Health education activities are essential as to the proper handling of eggs and egg products aiming to minimize susceptibility to Salmonella infection.

Keywords: epidemiological investigation, food-borne disease, food safety, Salmonella enteritidis

Procedia PDF Downloads 143
6727 Stabilization of y-Sterilized Food, Packaging Materials by Synergistic Mixtures of Food-Contact Approval Stabilizers

Authors: Sameh A. S. Thabit Alariqi

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Food is widely packaged with plastic materials to prevent microbial contamination and spoilage. Ionizing radiation is widely used to sterilize the food-packaging materials. Sterilization by γ-radiation causes degradation for the plastic packaging materials such as embrittlement, stiffening, softening, discoloration, odour generation, and decrease in molecular weight. Many antioxidants can prevent γ-degradation but most of them are toxic. The migration of antioxidants to its environment gives rise to major concerns in case of food packaging plastics. In this attempt, we have aimed to utilize synergistic mixtures of stabilizers which are approved for food-contact applications. Ethylene-propylene-diene terpolymer (EPDM) have been melt-mixed with hindered amine stabilizers (HAS), phenolic antioxidants and organo-phosphites (hydroperoxide decomposer). Results were discussed by comparing the stabilizing efficiency of mixtures with and without phenol system. Among phenol containing systems where we mostly observed discoloration due to the oxidation of hindered phenol, the combination of secondary HAS, tertiary HAS, organo-phosphite and hindered phenol exhibited improved stabilization efficiency than single or binary additive systems. The mixture of secondary HAS and tertiary HAS, has shown antagonistic effect of stabilization. However, the combination of organo-phosphite with secondary HAS, tertiary HAS and phenol antioxidants have been found to give synergistic even at higher doses of -sterilization. The effects have been explained through the interaction between the stabilizers. After γ-irradiation, the consumption of oligomeric stabilizer significantly depends on the components of stabilization mixture. The effect of the organo-phosphite antioxidant on the overall stability has been discussed.

Keywords: ethylene-propylene-diene terpolymer, synergistic mixtures, gamma sterilization, gamma stabilization

Procedia PDF Downloads 440
6726 Association between Levels of Volatile Organic Compound Metabolites and Cigarette Smoking-Related Urothelial Carcinoma

Authors: Chi-Jung Chung, Chao-Hsiang Chang, Chiu-Shong Liu, Sheng-Wei Li, Mu-Chi Chung, Ting-Jie Wen, Hui-Ling Lee

Abstract:

Cigarette smoke contains volatile organic compounds (VOCs), such as acrylamide, 1,3-butadiene, and benzene. This study aimed to explore the associations between the urinary levels of cotinine and VOC metabolites and the risk of urothelial carcinoma (UC). A hospital-based case–control study involving two groups matched on the basis of age ( ± 3 years) and gender was designed. UC was clinically diagnosed through urological examinations and pathologically verified. Smoking-related information was collected through questionnaires and face-to-face interviews with all study participants. Urine samples were collected for the analysis of the urinary levels of VOC metabolites, cotinine, and 8-hydroxydeoxygua- nosine (8-OHdG), which was selected as a proxy of oxidative stress. Multiple logistic regressions were applied to estimate the risk of UC. The urinary cotinine and 8-OHdG levels of the UC group were higher than those of the control group. The urinary levels of VOC metabolites, including N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), N- acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine, N-acetyl-S- (4- hydroxy-2-buten-1-yl)-Lcysteine-3, trans, trans-muconic acid (t,t- MA), and S-phenylmercapturic acid (SPMA) increased as the urinary levels of cotinine increased. Relevant dose-response relationships between the risk of UC risk and the urinary levels of AAMA , t,t-MA, SPMA, and 8-OHdG were found after adjusting for potential risk factors. The UC risk of participants with high urinary levels of cotinine, AAMA, t,t-MA, SPMA, and 8-OHdG were 3.5–6-fold higher than those of other participants. Increased urinary levels of VOC metabolites were associated with smoking-related UC risk. The development of UC should be explored in large-scale in vitro or in vivo studies with the repeated measurement of VOC metabolites.

Keywords: volatile organic compound, urothelial carcinoma, cotinine, 8-hydroxydeoxyguanosine

Procedia PDF Downloads 141
6725 Control of a Quadcopter Using Genetic Algorithm Methods

Authors: Mostafa Mjahed

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This paper concerns the control of a nonlinear system using two different methods, reference model and genetic algorithm. The quadcopter is a nonlinear unstable system, which is a part of aerial robots. It is constituted by four rotors placed at the end of a cross. The center of this cross is occupied by the control circuit. Its motions are governed by six degrees of freedom: three rotations around 3 axes (roll, pitch and yaw) and the three spatial translations. The control of such system is complex, because of nonlinearity of its dynamic representation and the number of parameters, which it involves. Numerous studies have been developed to model and stabilize such systems. The classical PID and LQ correction methods are widely used. If the latter represent the advantage to be simple because they are linear, they reveal the drawback to require the presence of a linear model to synthesize. It also implies the complexity of the established laws of command because the latter must be widened on all the domain of flight of these quadcopter. Note that, if the classical design methods are widely used to control aeronautical systems, the Artificial Intelligence methods as genetic algorithms technique receives little attention. In this paper, we suggest comparing two PID design methods. Firstly, the parameters of the PID are calculated according to the reference model. In a second phase, these parameters are established using genetic algorithms. By reference model, we mean that the corrected system behaves according to a reference system, imposed by some specifications: settling time, zero overshoot etc. Inspired from the natural evolution of Darwin's theory advocating the survival of the best, John Holland developed this evolutionary algorithm. Genetic algorithm (GA) possesses three basic operators: selection, crossover and mutation. We start iterations with an initial population. Each member of this population is evaluated through a fitness function. Our purpose is to correct the behavior of the quadcopter around three axes (roll, pitch and yaw) with 3 PD controllers. For the altitude, we adopt a PID controller.

Keywords: quadcopter, genetic algorithm, PID, fitness, model, control, nonlinear system

Procedia PDF Downloads 431