Search results for: natural population
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10725

Search results for: natural population

3195 Cement Bond Characteristics of Artificially Fabricated Sandstones

Authors: Ashirgul Kozhagulova, Ainash Shabdirova, Galym Tokazhanov, Minh Nguyen

Abstract:

The synthetic rocks have been advantageous over the natural rocks in terms of availability and the consistent studying the impact of a particular parameter. The artificial rocks can be fabricated using variety of techniques such as mixing sand and Portland cement or gypsum, firing the mixture of sand and fine powder of borosilicate glass or by in-situ precipitation of calcite solution. In this study, sodium silicate solution has been used as the cementing agent for the quartz sand. The molded soft cylindrical sandstone samples are placed in the gas-tight pressure vessel, where the hardening of the material takes place as the chemical reaction between carbon dioxide and the silicate solution progresses. The vessel allows uniform disperse of carbon dioxide and control over the ambient gas pressure. Current paper shows how the bonding material is initially distributed in the intergranular space and the surface of the sand particles by the usage of Electron Microscopy and the Energy Dispersive Spectroscopy. During the study, the strength of the cement bond as a function of temperature is observed. The impact of cementing agent dosage on the micro and macro characteristics of the sandstone is investigated. The analysis of the cement bond at micro level helps to trace the changes to particles bonding damage after a potential yielding. Shearing behavior and compressional response have been examined resulting in the estimation of the shearing resistance and cohesion force of the sandstone. These are considered to be main input values to the mathematical prediction models of sand production from weak clastic oil reservoir formations.

Keywords: artificial sanstone, cement bond, microstructure, SEM, triaxial shearing

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3194 Impact of E-Resources and Its Acceessability by Faculty and Research Scholars of Academic Libraries: A Case Study

Authors: M. Jaculine Mary

Abstract:

Today electronic resources are considered as an integral part of information sources to impart efficient services to the people aspiring to acquire knowledge in different fields. E-resources are those resources which include documents in e-format that can be accessed via the Internet in a digital library environment. The present study focuses on accessibility and use of e-resources by faculty and research scholars of academic libraries of Coimbatore, TamilNadu, India. The main objectives are to identify their purpose of using e-resources, know the users’ Information and Communication Technology (ICT) skills, identify satisfaction level of availability of e-resources, use of different e-resources, overall user satisfaction of using e-resources, impact of e-resources on their research and problems faced by them in the access of e-resources. The research methodology adopted to collect data for this study includes analysis of survey reports carried out by distributing questionnaires to the users. The findings of the research are based on the study of responses received from questionnaires distributed to a sample population of 200 users. Among the 200 respondents, 55 percent of research students and 45 percent of faculty members were users of e-resources. It was found that a majority of the users agreed that relevant, updated information at a fast pace had influenced them to use e-resources. Most of the respondents were of the view that more numbers of computers in the library would facilitate quick learning. Academic libraries have to take steps to arrange various training and orientation programmes for research students and faculty members to use the availability of e-resources. This study helps the librarian in planning and development of e-resources to provide modern services to their users of libraries. The study recommends that measures should be taken to increase the accessibility level of e-resource services among the information seekers for increasing the best usage of available electronic resources in the academic libraries.

Keywords: academic libraries, accessibility, electronic resources, satisfaction level, survey

Procedia PDF Downloads 125
3193 Retrospective Study on the Prognosis of Patients with New-Onset Atrial Fibrillation to Evaluate the Risk of Developing Occult Cancer in Absence of Concurrent Chronic Inflammatory Disease

Authors: Helen Huang, Francisco Javier Quesada Ocet, Blanca Quesada Oce, Javier Jimenez Bello, Victor Palanca Gil, Alba Cervero Rubio, Ana Paya Chaume, Alejandro Herreros-Pomares, Fernando Vidal-Vanaclocha, Rafael Paya Serrano, Aurelio Quesada Dorador, Monica Soliman

Abstract:

Background: Cancer favors both the pro-inflammatory state and autonomic dysfunction, two important mechanisms in the genesis of AF. Atrial remodeling might be caused as a result of paraneoplastic conditions or the result of direct expression of neoplasia. Here, we hypothesize that cancer, through inflammatory mediators, may favor the appearance of AF and patients with the first episode of AF could have a higher risk of developing cancer. Method: Data was collected from patients who attended the emergency department of our hospital for the first episode of AF, diagnosed electrocardiographically, between 2010-2015 (n = 712). The minimum follow-up was 2 years, recording the appearance of cancer, total mortality, recurrences of AF and other events. Patients who developed cancer and those who did not during the 2 years after the onset of AF were compared, as well as with the incidence of cancer in Spain in 2012. Results: After 2 years, 35 patients (4.91%) were diagnosed with cancer, with an annual incidence of 2.45%. Hematological neoplasms were the most frequent (34.28%). The cancer group was older (76.68 +/-12.75 years vs 74.16 +/-12.71; p <0.05) and had fewer typical symptoms (palpitations) (33.38% vs 14.28% , p <0.05). The incidence of cancer in Spain during 2012 was 0.46%, much lower than our sample. When comparing the incidence by age, these differences were maintained both in those over 65 years of age and in those under 65 years of age (2.17% vs. 0.28%; 0.28% vs. 0.18% respectively). Discussion: Therefore, a high incidence of cancer in patients with the first episode of AF was observed (the annual incidence of 2.45% after the onset of AF is 6.1 times that of the general population). After the evaluation of patients with AF in their first detected episode, surveillance of the appearance of cancer should be considered in clinical practice.

Keywords: cancer, cardiovascular outcomes, atrial fibrillation, inflammation

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3192 Electromagnetic Fields Characterization of an Urban Area in Lagos De Moreno Mexico and Its Correlation with Public Health Hazards

Authors: Marco Vinicio Félix Lerma, Efrain Rubio Rosas, Fernando Ricardez Rueda, Victor Manuel Castaño Meneses

Abstract:

This paper reports a spectral analysis of the exposure levels of radiofrequency electromagnetic fields originating from a wide variety of telecommunications sources present in an urban area of Lagos de Moreno, Jalisco, Mexico. The electromagnetic characterization of the urban zone under study was carried out by measurements in 118 sites. Measurements of TETRA,ISM434, LTE800, ISM868, GSM900, GSM1800, 3G UMTS,4G UMTS, Wlan2.4, LTE2.6, DECT, VHF Television and FM radio signals were performed at distances ranging over 10 to 1000m from 87 broadcasting towers concentrated in an urban area of about 3 hectares. The aim of these measurements is the evaluation of the electromagnetic fields power levels generated by communication systems because of their interaction with the human body. We found that in certain regions the general public exposure limits determined by ICNIRP (International Commission of Non Ionizing Radiation Protection) are overpassed from 5% up to 61% of the upper values, indicating an imminent health public hazard, whereas in other regions we found that these limits are not overpassed. This work proposes an electromagnetic pollution classification for urban zones according with ICNIRP standards. We conclude that the urban zone under study presents diverse levels of pollution and that in certain regions an electromagnetic shielding solution is needed in order to safeguard the health of the population that lives there. A practical solution in the form of paint coatings and fiber curtains for the buildings present in this zone is also proposed.

Keywords: electromagnetic field, telecommunication systems, electropollution, health hazards

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3191 3+3 Regional Cooperation Format and the South Caucasus

Authors: Eka Darbaidze

Abstract:

Due to its important geopolitical location and strategic economic situation, the South Caucasus has been a region that has been a crossroads of interests between different states and empires since ancient times. Over the centuries, the forms of international relations with regard to the South Caucasus region have been constantly changing, however, the national interests of the Caucasian nations as well as the interests of the regional hegemonic powers in relation to the countries of the South Caucasus have remained almost unchanged. The conflict-ridden South Caucasus's attempt to create a new format of regional cooperation has a rather rich history, dating back to the collapse of the Soviet Union. However, despite the diversity of initiatives, they do not deviate from the format of political statements and it is natural that the case was never settled before their implementation, as none of the previous cooperation initiatives was able to reach all members of the region. The current regional co-operation platform is linked to the name of Turkish President Recep Tayyip Erdogan, who spoke out about the initiative during a visit to Azerbaijan. The so-called 3 + 3 platform for regional cooperation involves cooperation between three countries in the South Caucasus (Armenia, Azerbaijan and Georgia) and three "big neighbors" - Russia, Turkey and Iran. Very soon, the initiative received a positive response from the authorities of Azerbaijan, Iran and Armenia. According to them, this cooperation platform will strengthen cooperation between the countries involved in the regional platform and will focus on security, economic and transport issues. Our goal is to determine the interests of the main regional actors involved in the South Caucasus Cooperation Platform (3 + 3): Iran, Russia and Turkey. Our goal is also to determine what threats, risks or benefits may be associated with the involvement of the three countries of the South Caucasus: Azerbaijan, Armenia and Georgia in this platform and what will be the consequences for Georgia, whose 20% of its internationally recognized borders are still occupied by Russia and whose territory is still under creeping occupation.

Keywords: South Caucasus, Georgia's interest, the interests of Iran, the interests of Turkey, Russian interests, Georgia's occupation

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3190 A Structured Mechanism for Identifying Political Influencers on Social Media Platforms Top 10 Saudi Political Twitter Users

Authors: Ahmad Alsolami, Darren Mundy, Manuel Hernandez-Perez

Abstract:

Social media networks, such as Twitter, offer the perfect opportunity to either positively or negatively affect political attitudes on large audiences. A most important factor contributing to this effect is the existence of influential users, who have developed a reputation for their awareness and experience on specific subjects. Therefore, knowledge of the mechanisms to identify influential users on social media is vital for understanding their effect on their audience. The concept of the influential user is based on the pioneering work of Katz and Lazarsfeld (1959), who created the concept of opinion leaders' to indicate that ideas first flow from mass media to opinion leaders and then to the rest of the population. Hence, the objective of this research was to provide reliable and accurate structural mechanisms to identify influential users, which could be applied to different platforms, places, and subjects. Twitter was selected as the platform of interest, and Saudi Arabia as the context for the investigation. These were selected because Saudi Arabia has a large number of Twitter users, some of whom are considerably active in setting agendas and disseminating ideas. The study considered the scientific methods that have been used to identify public opinion leaders before, utilizing metrics software on Twitter. The key findings propose multiple novel metrics to compare Twitter influencers, including the number of followers, social authority and the use of political hashtags, and four secondary filtering measures. Thus, using ratio and percentage calculations to classify the most influential users, Twitter accounts were filtered, analyzed and included. The structured approach is used as a mechanism to explore the top ten influencers on Twitter from the political domain in Saudi Arabia.

Keywords: twitter, influencers, structured mechanism, Saudi Arabia

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3189 Rheological Assessment of Oil Well Cement Paste Dosed with Cellulose Nanocrystal (CNC)

Authors: Mohammad Reza Dousti, Yaman Boluk, Vivek Bindiganavile

Abstract:

During the past few decades, oil and natural gas consumption have increased significantly. The limited amount of hydrocarbon resources on earth has led to a stronger desire towards efficient drilling, well completion and extracting, with the least time, energy and money wasted. Well cementing is one of the most crucial and important steps in any well completion, to fill the annulus between the casing string and the well bore. However, since it takes place at the end of the drilling process, a satisfying and acceptable job is rarely done. Hence, a large and significant amount of time and energy is then spent in order to do the required corrections or retrofitting the well in some cases. Oil well cement paste needs to be pumped during the cementing process, therefore the rheological and flow behavior of the paste is of great importance. This study examines the use of innovative cellulose-based nanomaterials on the flow properties of the resulting cementitious system. The cementitious paste developed in this research is composed of water, class G oil well cement, bentonite and cellulose nanocrystals (CNC). Bentonite is used as a cross contamination component. Initially, the influence of CNC on the flow and rheological behavior of CNC and bentonite suspensions was assessed. Furthermore, the rheological behavior of oil well cement pastes dosed with CNC was studied using a steady shear parallel-plate rheometer and the results were compared to the rheological behavior of a neat oil well cement paste with no CNC. The parameters assessed were the yield shear stress and the viscosity. Significant changes in yield shear stress and viscosity were observed due to the addition of the CNC. Based on the findings in this study, the addition of a very small dosage of CNC to the oil well cement paste results in a more viscous cement slurry with a higher yield stress, demonstrating a shear thinning behavior.

Keywords: cellulose nanocrystal, flow behavior, oil well cement, rheology

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3188 Exploring Hydrogen Embrittlement and Fatigue Crack Growth in API 5L X52 Steel Pipeline Under Cyclic Internal Pressure

Authors: Omar Bouledroua, Djamel Zelmati, Zahreddine Hafsi, Milos B. Djukic

Abstract:

Transporting hydrogen gas through the existing natural gas pipeline network offers an efficient solution for energy storage and conveyance. Hydrogen generated from excess renewable electricity can be conveyed through the API 5L steel-made pipelines that already exist. In recent years, there has been a growing demand for the transportation of hydrogen through existing gas pipelines. Therefore, numerical and experimental tests are required to verify and ensure the mechanical integrity of the API 5L steel pipelines that will be used for pressurized hydrogen transportation. Internal pressure loading is likely to accelerate hydrogen diffusion through the internal pipe wall and consequently accentuate the hydrogen embrittlement of steel pipelines. Furthermore, pre-cracked pipelines are susceptible to quick failure, mainly under a time-dependent cyclic pressure loading that drives fatigue crack propagation. Meanwhile, after several loading cycles, the initial cracks will propagate to a critical size. At this point, the remaining service life of the pipeline can be estimated, and inspection intervals can be determined. This paper focuses on the hydrogen embrittlement of API 5L steel-made pipeline under cyclic pressure loading. Pressurized hydrogen gas is transported through a network of pipelines where demands at consumption nodes vary periodically. The resulting pressure profile over time is considered a cyclic loading on the internal wall of a pre-cracked pipeline made of API 5L steel-grade material. Numerical modeling has allowed the prediction of fatigue crack evolution and estimation of the remaining service life of the pipeline. The developed methodology in this paper is based on the ASME B31.12 standard, which outlines the guidelines for hydrogen pipelines.

Keywords: hydrogen embrittlement, pipelines, transient flow, cyclic pressure, fatigue crack growth

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3187 Effect of Therapeutic Exercises with or without Positional Release Technique in Treatment of Chronic Mechanical Low Back Pain Patients a Randomized Controlled Trial

Authors: Ghada M. R. Koura, Mohamed N. Mohamed, Ahmed M. F. El Shiwi

Abstract:

Chronic mechanical Low back dysfunction (CMLBD) is the most common problem of the working-age population in modern industrial sociaty; it causes a substantial economic burden due to the wide use of medical services and absence from work. Aim of work: the aim of this study was to investigate the effect of positional release technique on patients with chronic mechanical low back pain. Materials and Methods: Thirty two patients from both sexes were diagnosed with CMLBP, aged 20 to 45 years and were divided randomly into two equal groups; sixteen patients each; group A (control group) received therapeutic exercises that include (Stretch and Strength exercises for back and abdominal muscles). Group B (experimental group) received therapeutic exercises with positional release technique; treatment was applied 3 days/week for 4 weeks. Pain was measured by Visual Analogue Scale, Lumbar range of motion was measured by Inclinometer and Functional disability was measured by Oswestry disability scale. Measurements were taken at two intervals pre-treatment and post-treatment. Results: Data obtained was analyzed via paired and unpaired t-Test. There were statistical differences between the 2 groups, where the experimental group showed greater improvement than control group. Conclusion: Positional release technique is considered as an effective treatment for reducing pain, functional disability and increasing lumbar range of motion in individuals with chronic mechanical low back pain.

Keywords: chronic mechanical low back pain, traditional physical therapy program, positional release technique, randomized controlled trial

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3186 The Effect of Flow Discharge on Suspended Solids Transport in the Nakhon-Nayok River

Authors: Apichote Urantinon

Abstract:

Suspended solid is one factor for water quality in open channel. It affects various problems in waterways that could cause high sedimentation in the channels, leading to shallowness in the river. It is composed of the organic and inorganic materials which can settle down anywhere along the open channel. Thus, depends on the solid amount and its composition, it occupies the water body capacity and causes the water quality problems simultaneously. However, the existing of suspended solid in the water column depends on the flow discharge (Q) and secchi depth (sec). This study aims to examine the effect of flow discharge (Q) and secchi depth (sec) on the suspended solids concentration in open channel and attempts to establish the formula that represents the relationship between flow discharges (Q), secchi depth (sec) and suspended solid concentration. The field samplings have been conducted in the Nakhon-Nayok river, during the wet season, September 15-16, 2014 and dry season, March 10-11, 2015. The samplings with five different locations are measured. The discharge has been measured onsite by floating technics, the secchi depth has been measured by secchi disc and the water samples have been collected at the center of the water column. They have been analyzed in the laboratory for the suspended solids concentration. The results demonstrate that the decrease in suspended solids concentration is dependent on flow discharge, since the natural processes in erosion consists of routing of eroded material. Finally, an empirical equation to compute the suspended solids concentration that shows an equation (SScon = 9.852 (sec)-0.759 Q0.0355) is developed. The calculated suspended solids concentration, with uses of empirical formula, show good agreement with the record data as the R2 = 0.831. Therefore, the empirical formula in this study is clearly verified.

Keywords: suspended solids concentration, the Nakhon-Nayok river, secchi depth, floating technics

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3185 Identifying and Evaluating the Effectiveness of Communication Channels between Employees and Management Based on the EFQM Excellence Model

Authors: Mehrdad Hosseinishakib, Mozhgan Chakani, Gholamreza Babaei

Abstract:

This study aims to investigate the relationship between the bilateral communication channels, communication technologies with effective communications and communication technologies, employee participation in motivated decision-making of employees using the EFQM excellence model in Education Organization of Area 4 in Karaj. This research is an applied research in terms of the purpose and is a descriptive survey research in terms of nature and method and assesses the current situation using field studies. The statistical population consists of all employees and managers of Education Organization of Area 4 in Karaj including 5442 persons and random sampling was used and sample size is 359 using Cochran formula. Measurement tool is a researcher-made questionnaire with 20 questions including two categories of expertise and general questions. The first category includes general questions about respondents' personal characteristics such as gender and level of education, work experience and courses of study. The second category includes expertise questions of the questionnaire that have been designed to test research hypotheses that its reliability was approved by Cronbach's alpha coefficient 0.916 and its validity was approved according to the vies of teachers and some senior managers of Education Organization of Area 4 in Karaj. The results of the analysis of the findings show that there is a significant relationship between mutual communication channels, communication technologies with effective communication between employees and management. There is also a significant relationship between communication technologies and employee motivation and employee participation in their motivated decision-making in Education Organization of Area 4 in Karaj.

Keywords: communication channels, effective communication, EFQM model, ANOVA

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3184 Potential of Rice Husk Ash as a Partial Cement Replacement in Concrete for Highways Application

Authors: Ash Ahmed, Fraser Hyndman, Heni Fitriani, John Kamau

Abstract:

The highway pavement is the biggest structural asset a government can construct and maintain. Concrete rigid pavements are used to carry traffic in large volumes across countries safely and efficiently. Pavement quality concrete mixes have high levels of cement which contribute to up to 10% of global CO₂ emissions. Currently the UK specifies (ground granulated blastfurnace slag) GGBS and (pulverised fuel ash) PFA to reduce the quantity of cement used in pavement construction. GGBS and PFA come from heavy industry that should not be relied upon to improve the sustainability of construction materials. This report shows that cement in pavement quality concrete can be replaced with rice husk ash (RHA) without causing adverse effects to the mechanical properties required for highways. RHA comes from the food production industry and is vital for the growing global population. It is thus a socially responsible objective to use a pozzolan in highway pavement construction that is sourced from an environmentally friendly industry. The report investigates the properties of RHA mixes and compares them to existing pavement quality mixes already used and specified. The report found that sieving RHA and not grinding it gives the best performance. Due to the low density of RHA the investigation found that replacing cement by volume rather than weight provided the best results. Findings showed that CEM II mixed with 20% RHA meets the required specification for pavement quality concrete and mitigates using the comparative CEM I. The investigation also notes that RHA is observed to be more reactive with CEM II rather than CEM I and suits early strength gains required for pavement construction. The report concludes that RHA is a sustainable material that reduces the embodied CO₂ of pavement quality concrete, which is well suited for UK highway specifications and has the potential to improve the lives of people living in the developing countries.

Keywords: pavement, pozzolan, rice husk ash, sustainable concrete

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3183 Correlation between Neck Circumference and Other Anthropometric Indices as a Predictor of Obesity

Authors: Madhur Verma, Meena Rajput, Kamal Kishore

Abstract:

Background: The general view that obesity is a problem of prosperous Western countries has been repealed with substantial evidence showing that middle-income countries like India are now at the heart of a fat explosion. Neck circumference has evolved as a promising index to measure obesity, because of the convenience of its use, even in culture sensitive population. Objectives: To determine whether neck circumference (NC) was associated with overweight and obesity and contributed to the prediction like other classical anthropometric indices. Methodology: Cross-sectional study consisting of 1080 adults (> 19 years) selected through Multi-stage random sampling between August 2013 and September 2014 using the pretested semi-structured questionnaire. After recruitment, the demographic and anthropometric parameters [BMI, Waist & Hip Circumference (WC, HC), Waist to hip ratio (WHR), waist to height ratio (WHtR), body fat percentage (BF %), neck circumference (NC)] were recorded & calculated as per standard procedures. Analysis was done using appropriate statistical tests. (SPSS, version 21.) Results: Mean age of study participants was 44.55+15.65 years. Overall prevalence of overweight & obesity as per modified criteria for Asian Indians (BMI ≥ 23 kg/m2) was 49.62% (Females-51.48%; Males-47.77%). Also, number of participants having high WHR, WHtR, BF%, WC & NC was 827(76.57%), 530(49.07%), 513(47.5%), 537(49.72%) & 376(34.81%) respectively. Variation of NC, BMI & BF% with age was non- significant. In both the genders, as per the Pearson’s correlational analysis, neck circumference was positively correlated with BMI (men, r=0.670 {p < 0.05}; women, r=0.564 {p < 0.05}), BF% (men, r=0.407 {p < 0.05}; women, r= 0.283 {p < 0.05}), WC (men, r=0.598{p < 0.05}; women, r=0.615 {p < 0.05}), HC (men, r=0.512{p < 0.05}; women, r=0.523{p < 0.05}), WHR (men, r= 0.380{p > 0.05}; women, r=0.022{p > 0.05}) & WHtR (men, r=0.318 {p < 0.05}; women, r=0.396{p < 0.05}). On ROC analysis, NC showed good discriminatory power to identify obesity with AUC (AUC for males: 0.822 & females: 0.873; p- value < 0.001) with maximum sensitivity and specificity at a cut-off value of 36.55 cms for males & 34.05cms for females. Conclusion: NC has fair validity as a community-based screener for overweight and obese individuals in the study context and has also correlated well with other classical indices.

Keywords: neck circumference, obesity, anthropometric indices, body fat percentage

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3182 Recovery of Au and Other Metals from Old Electronic Components by Leaching and Liquid Extraction Process

Authors: Tomasz Smolinski, Irena Herdzik-Koniecko, Marta Pyszynska, M. Rogowski

Abstract:

Old electronic components can be easily found nowadays. Significant quantities of valuable metals such as gold, silver or copper are used for the production of advanced electronic devices. Old useless electronic device slowly became a new source of precious metals, very often more efficient than natural. For example, it is possible to recover more gold from 1-ton personal computers than seventeen tons of gold ore. It makes urban mining industry very profitable and necessary for sustainable development. For the recovery of metals from waste of electronic equipment, various treatment options based on conventional physical, hydrometallurgical and pyrometallurgical processes are available. In this group hydrometallurgy processes with their relatively low capital cost, low environmental impact, potential for high metal recoveries and suitability for small scale applications, are very promising options. Institute of Nuclear Chemistry and Technology has great experience in hydrometallurgy processes especially focused on recovery metals from industrial and agricultural wastes. At the moment, urban mining project is carried out. The method of effective recovery of valuable metals from central processing units (CPU) components has been developed. The principal processes such as acidic leaching and solvent extraction were used for precious metals recovery from old processors and graphic cards. Electronic components were treated by acidic solution at various conditions. Optimal acid concentration, time of the process and temperature were selected. Precious metals have been extracted to the aqueous phase. At the next step, metals were selectively extracted by organic solvents such as oximes or tributyl phosphate (TBP) etc. Multistage mixer-settler equipment was used. The process was optimized.

Keywords: electronic waste, leaching, hydrometallurgy, metal recovery, solvent extraction

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3181 Blue Whale Body Condition from Photographs Taken over a 14-Year Period in the North East Pacific: Annual Variations and Connection to Measures of Ocean Productivity

Authors: Rachel Wachtendonk, John Calambokidis, Kiirsten Flynn

Abstract:

Large marine mammals can serve as an indicator of the overall state of the environment due to their long lifespan and apex position in marine food webs. Reductions in prey, driven by changes in environmental conditions can have resounding impacts on the trophic system as a whole; this can manifest in reduced fat stores that are visible on large whales. Poor health can lead to reduced survivorship and fitness, both of which can be detrimental to a recovering population. A non-invasive technique was used for monitoring blue whale health and for seeing if it changes with ocean conditions. Digital photographs of blue whales taken in the NE Pacific by Cascadia Research and collaborators from 2005-2018 (n=3,545) were scored for overall body condition based on visible vertebrae and body shape on a scale of 0-3 where a score of 0 indicated best body condition and a score of 3 indicated poorest. The data was analyzed to determine if there were patterns in the health of whales across years and whether overall poor health was related to oceanographic conditions and predictors of prey abundance on the California coast. The year was a highly significant factor in body condition (Chi-Square, p<0.001). The proportion of whales showing poor body condition (scores 2 & 3) overall was 33% but by year varied widely from a low of 18% (2008) to a high of 55% (2015). The only two years where >50% of animals had poor body condition were 2015 and 2017 (no other year was above 45%). The 2015 maximum proportion of whales in poor body condition coincide with the marine heat wave that affected the NE Pacific 2014-16 and impacted other whale populations. This indicates that the scoring method was an effective way to evaluate blue whale health and how they respond to a changing ocean.

Keywords: blue whale, body condition, environmental variability, photo-identification

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3180 An Investigation on the Effect of Railway Track Elevation Project in Taichung Based on the Carbon Emissions

Authors: Kuo-Wei Hsu, Jen-Chih, Chao, Pei-Chen, Wu

Abstract:

With the rapid development of global economy, the increasing population, the highly industrialization, greenhouse gas emission and the ozone layer damage, the Global Warming happens. Facing the impact of global warming, the issue of “green transportation” began to be valued and promoted in each city. Taichung has been elected as the model of low-carbon city in Taiwan. To comply with international trends and the government policy, we tried to promote the energy saving and carbon reduction to create a “low-carbon Taichung with green life and eco-friendly economy”. To cooperate with the “green transportation” project, Taichung has promoted a number of public transports constructions and traffic policy in recent years like BRT, MRT, etc. The elevated railway is one of those important constructions. Cooperating with the green transport policy, elevated railway could help to achieve the carbon reduction for this low-carbon city. The current studies of the carbon emissions associated with railways and roads are focusing on the assessment on paving material, institutional policy and economic benefit. Except for changing the mode of transportation, elevated railways/roads also create space under the bridge. However, there is no research about the carbon emissions of the space underneath the elevated section up until now. This study investigated the effect of railway track elevation project in Taichung based on the carbon emissions and the factors that affect carbon emissions by research related theory and literature analysis. This study concluded that : railway track elevation increased the public transit, the bike lanes, the green areas and walking spaces. In the other hand it reduced the traffic congestions, the use of motorcycles as well as automobiles for carbon emissions.

Keywords: low-carbon city, green transportation, carbon emissions, Taichung, Taiwan

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3179 Developing an Automated Protocol for the Wristband Extraction Process Using Opentrons

Authors: Tei Kim, Brooklynn McNeil, Kathryn Dunn, Douglas I. Walker

Abstract:

To better characterize the relationship between complex chemical exposures and disease, our laboratory uses an approach that combines low-cost, polydimethylsiloxane (silicone) wristband samplers that absorb many of the chemicals we are exposed to with untargeted high-resolution mass spectrometry (HRMS) to characterize 1000’s of chemicals at a time. In studies with human populations, these wristbands can provide an important measure of our environment: however, there is a need to use this approach in large cohorts to study exposures associated with the disease. To facilitate the use of silicone samplers in large scale population studies, the goal of this research project was to establish automated sample preparation methods that improve throughput, robustness, and scalability of analytical methods for silicone wristbands. Using the Opentron OT2 automated liquid platform, which provides a low-cost and opensource framework for automated pipetting, we created two separate workflows that translate the manual wristband preparation method to a fully automated protocol that requires minor intervention by the operator. These protocols include a sequence generation step, which defines the location of all plates and labware according to user-specified settings, and a transfer protocol that includes all necessary instrument parameters and instructions for automated solvent extraction of wristband samplers. These protocols were written in Python and uploaded to GitHub for use by others in the research community. Results from this project show it is possible to establish automated and open source methods for the preparation of silicone wristband samplers to support profiling of many environmental exposures. Ongoing studies include deployment in longitudinal cohort studies to investigate the relationship between personal chemical exposure and disease.

Keywords: bioinformatics, automation, opentrons, research

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3178 Documentation Project on Decorated Wooden Coffins From Luxor, in the Cairo Museum

Authors: Hassan Mohmed, Mohamed Ismail, Aiman Rezk

Abstract:

Introduction: This project aims to document and preserve decorated wooden coffins which were discovered in Luxor by Egyptian mission at Luxor, (SR Numbers:2514,2519,2520,2521,5469).These decorated wooden coffins dates back to Egyptian New Kingdom period and has been transferred to the Cairo Museum, to be displayed at the museum. These decorated wooden coffins discovered in the cache-tomb of Bab el-gasus at Deir el-Bahari, Luxor. This site has been dictated for the burials of priests of Amun through 18th Dynasty the coffins owners held these titles, which are as follows: "the embalmer of the beautiful-house (the place of embalming)" and "the servant in the place of truth". Methodology: Methodology: The project objectives making such decorated wooden coffins more visible to visitors through the use of 3D reconstructed coffins and high resolution photos which describe the history of using the wooden coffins during the Ancient Egyptian history Especially, The Cairo Museum is going to exhibit decorated wooden coffins in New kingdom. The project goals is to document decorated wooden coffins and arrange an exhibition, where such decorated wooden coffins going to be displayed next to the Ramses 2nd coffin, This research focuses on the text analyses and the technology. Paleographic information found on these objects. Conclusion: The project shows the importance of using coffins in Ancient Egypt, and connecting their usage through Ancient Egyptian periods; the coffins had a unique Symbolized in ancient Egypt and connect the public with their kings. The Egyptian put coffins in their tombs that they hope to save their bodies’ afterlife. This research will be beneficial and useful for the heritage and ancient civilizations, Indeed this study will open a destination in order to know how to identify these collections and how to exhibit them commensurate with the natural of the ancient Egyptian history and heritage.

Keywords: archaeology, decorated wooden coffins, 3D digital tools for heritage management, museums

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3177 The Impact of Leadership Styles and Coordination on Employees Performance in the Nigerian Banking Sector

Authors: Temilola Akinbolade, Bukola Okunade, Karounwi Okunade

Abstract:

Leadership is a subject of direction. Direction entails ensuring that employees carryout the jobs assigned to them. In order to direct subordinates, a manager must lead, motivate, communicate and ensure effective co-ordination of activities so that enterprise objectives are achieved. The purpose of the study was to find out the impact of Leadership Styles on Employees Performance, Study of Wema Bank Plc. Leadership has been described as a tool used in influencing people in order to willingly get a particular or task done. The importance of leadership is followership. That is the willingness of people to follow what makes a person a leader. A sample size of 150 was systematically selected from the study population using the statistical packages for Social Science (SPSS) formula. Based on this, questionnaire was designed and administered. Out of the 105 copies of the questionnaire administered. 150 were recovered, 45 were discarded for improper filling and mutilation while the remaining 105 were used for statistical analysis. Chi-square was employed in testing the hypothesis. The following findings were discovered in the course of the study: how leadership enhances employee’s performance, 85.7% of the respondents were in agreement. Also how implementation of workers social welfare packages enhance the employees performance. 88.6 percent of the respondents in agreement. Over the years, some leadership styles adopted by managers and administrators have an impact on the level of employee’s performance in workplace and this has led to the inefficient and ineffective attainment of organizational goals and objectives. Due to the inability of employees to perform to set standard, this research work will also indicate some ways through which high employee performance will be attained most especially with regards to the leadership style adopted by the management that is managers and administrators. It was also discovered that collective intelligence of employees leads to high employee’s performance 82.9 percent of the respondent in agreement.

Keywords: leadership, employees, performance, banking sector

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3176 Silica Nanofibres – Promising Material for Regenerative Medicine

Authors: Miroslava Rysová, Zdena Syrová, Tomáš Zajíc, Petr Exnar

Abstract:

Currently, attention of tissue engineers has been attracted to novel nanofibrous materials having advanced properties and ability to mimic extracellular matrix (ECM) by structure which makes them interesting candidates for application in regenerative medicine as scaffolding and/or drug delivering material. Throughout the last decade, more than 200 synthetic and natural polymers have been successfully electrospun leading to the formation of nanofibres with a wide range of chemical, mechanical and degradation properties. In this family, inorganic nanofibres represent very specific group offering an opportunity to manufacture inert to body, well degradable and in properties tunable material. Aim of this work, was to reveal unique properties of silica (SiO2, CAS 7631-86-9) nanofibres and their potential in field of regenerative medicine. Silica nanofibres were prepared by sol-gel method from tetraethyl orthosilicate (TEOS, CAS 78-10-4) as a precursor and subsequently manufactured by needleless electrospinning on NanospiderTM device. Silica nanofibres thermally stabilized under 200°C were confirmed to be fully biodegradable and soluble in several simulated body fluids. In vitro cytotoxicity tests of eluate (ES ISO 10993-5:1999) and in direct contact (ES ISO 10993-5:2009) showed no toxicity - e.g. cell viabilities reached values exceeding 80%. Those results were obtained equally from two different cell lines (Vero, 3T3). Non-toxicity of silaca nanofibres´ eluate was additionally confirmed in real time by testing on xCelligence (ACEA Biosciences, Inc.) device. Both cell types also showed good adhesion to material. To conclude, all mentioned results lead to resumption that silica nanofibres have a potential as material for regenerative medicine which opens door to further research.

Keywords: cytotoxicity, electrospinning, nanofibres, silica, tissue engineering

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3175 Application of Bacteriophages as Natural Antibiotics in Aquaculture

Authors: Chamilani Nikapitiya, Mahanama De Zoysa, Jehee Lee

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Most of the bacterial diseases are associated with high mortalities in aquaculture species and causing huge economic losses. Different approaches have been taken to prevent or control of bacterial diseases including use of vaccines, probiotics, chemotherapy, water quality management, etc. Antibiotics are widely applying as chemotherapy to control bacterial diseases, however, it has been shown that frequent use of antibiotics is favored to develop multi-drug resistance bacteria. Therefore, phages and phage encoded lytic proteins are known to be one of the most promising alternatives for antibiotics to avoid the emergence of antibiotic-resistant bacteria. We isolated and characterized the two lytic phages, namely pAh-1 and pAs-1 against pathogenic Aeromonas hydrophila and Aeromonas salmonicida, respectively. Morphological characteristics were analyzed by Transmission electron microscopy (TEM) and host strain specificities were tested with Aeromonas and other closely related bacterial strains. TEM analysis revealed that both pAh-1 and pAsm-1 are composed of an icosahedral head and a segmented tail, and we suggest that, they are new members of Myoviridae family. Genome sizes of isolated phages were estimated by restriction enzyme digestion of genomic DNA using selected endonucleases followed by agarose gel electrophoresis. Estimated genome size of pAh-1 and pAs-1 were approximately 64 Kbp and 120 Kbp, respectively. Both pAh-1 and pAs-1 have shown narrow host specificity. Moreover, protective effects of phage therapy against fish pathogenic A. hydrophila were investigated in zebrafish model. The survival rate was 40% higher when zebrafish received intra-peritoneal injection (i.p.) of pAh-1 were simultaneously challenge A. hydrophila (2 x 106 CFU/fish) compared to that without phage treatment. Overall results suggest that both pAh-1 and pAs-1 can be used as a potential phage therapy to control Aeromonas infections in aquaculture.

Keywords: Aeromonas infections, antibiotic resistance, bacteriophage, bio-control, lytic phage

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3174 Police Violence, Activism, and the Changing Rural United States: A Digital History and Mapping Narrative

Authors: Joel Zapata

Abstract:

Chicana/o Activism in the Southern Plains Through Time and Space, a digital history project available at PlainsMovement.com, helps reveal an understudied portion of the Chicana/o Civil Rights Movement: the way it unfolded on the Southern Plains. The project centers around an approachable interactive map and timeline along with a curated collection of materials. Therefore, the project provides a digital museum experience that has not emerged within the region’s museums. That is, this digital history project takes scholarly research to the wider public, making it is also a publicly facing history project. In this way, the project adds to both scholarly and socially significant conversations, showing that the region was home to a burgeoning wing of the Chicana/o Movement and that instances of police brutality largely spurred this wing of the social justice movement. Moreover, the curated collection of materials demonstrates that police brutality united the plains’ Mexican population across political ideology, a largely overlooked aspect within the study of Mexican American civil rights movements. Such a finding can be of use today since contemporary Latina/o social justice organizations generally ignore policing issues even amid a rise in national awareness regarding police abuse. In making history accessible to Mexican origin and Latina/o communities, these same communities may in-turn use the knowledge gained from historical research towards the betterment of their social positions—the foundational goal of Chicana/o history and the related field of Chicana/o Studies. Ultimately, this digital history project is intended to draw visitors to further explore the Chicana/o Civil Rights Movement within and beyond the plains.

Keywords: Chicana/o Movement, digital history, police brutality, newspapers, protests, student activism

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3173 Heritage of the Ancient Greco-Roman Cities and Harbors in the North West Coast of Egypt

Authors: Wessam Fekry Ibrahim Moussa

Abstract:

The northwest coast of Egypt embraces about 500 km of the Mediterranean coastline. The area covered extends from Alexandria on the East to the village of Sallum at Egypt's border with Libya in the west with an average depth of 20-70 km. When one looks at this long strip of land, one is struck by the fact that, from the archaeological point of view, one knows relatively little about this region during ancient times, its history, villages, inhabitants, and heritage. According to classical writers, in antiquity, the area seemed to be more populated and characterized by its rich buildings and inhabitants. They mentioned several Greco-Roman towns and harbors scattered along the coast nearly 2 thousand years ago. Strabo, for instance, in his book 17, confirmed the existence of about 12 several clusters along the coast, which varied between cities, villages, harbors, and small islands. Claudius Ptolemaeus also enumerated many marina sites as well as some small cities and villages. Unfortunately, nowadays, most of them have been lost either due to the extensive development of the north coast, Natural Disasters, or Erosion Factors. However, recent excavations carried out within the area revealed just a little of these settlements. The aim of this study is to reveal the secrets of the hidden heritage of those ancient sites and shed light on the role they played in the past, as some of them used to be stops on the trade route between Libya and Egypt (Strabo 17) or major centers for some of the international imports. The study will explore the archeological evidence using the analytical methodology to analyze each site and identify its features and significances in order to conclude the importance and role it once played during the past. Findings could be used by authorities and policymakers to utilize these heritage resources to improve cultural tourism within the area and enhance the tourist's experience.

Keywords: Greco Roman, heritage, ancient cities, north west coast

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3172 Assessing Economic Losses Of 2104 Flood Disaster: A Case Study on Dabong, Kelantan, Malaysia

Authors: Ahmad Hamidi Mohamed, Jamaluddin Othman, Mashitah Suid, Mohd Zaim Mohd Shukri

Abstract:

Floods are considered an annual natural disaster in Kelantan. However, the record-setting flood of 2014 was a 'tsunami-like disaster'. A study has been conducted with the objectives to assess the economic impact of the flood to the resident of Dabong area in Kelantan Darul Naim, Malaysia. This area was selected due to the severity during the flood. The impacts of flood on local people were done by conducting structured interviews with the use of questionnaires. The questionnaire was intended to acquire information on losses faced by Dabong residence. Questionnaires covered various areas of inconveniences suffered with respect to health effects, including illnesses suffered, their intensities, duration and their associated costs. Loss of productivity and quality of life was also assessed. Inquiries were made to Government agencies to obtain relevant statistical data regarding the loss due to the flood tragedy. The data collected by giving formal request to the governmental agencies and formal meetings were done. From the study a staggering amount of losses were calculated. This figure comes from losses of property, Farmers/Agriculture, Traders/Business, Health, Insurance and Governmental losses. Flood brings hardship to the people of Dabong and these losses of home will cause inconveniences to the society. The huge amount of economic loss extracted from this study shows that federal and state government of Kelantan need to find out the cause of the major flood in 2014. Fast and effective measures have to be planned and implemented in flood prone area to prevent same tragedy happens in the future.

Keywords: economic impact, flood tragedy, Malaysia, property losses

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3171 The Influence of Group Heuristics on Corporate Social Responsibility Messages Designed to Reduce Illegal Consumption

Authors: Kate Whitman, Zahra Murad, Joe Cox

Abstract:

Corporate social responsibility projects are suggested to motivate consumers to reciprocate good corporate deeds with their custom. When the projects benefit the ingroup vs the outgroup, such as locals rather than foreigners, the effect on reciprocity is suggested to be more powerful. This may be explained by group heuristics, a theory which indicates that favours to the ingroup (but not outgroup) are expected to be reciprocated, resulting in ingroup favouritism. The heuristic is theorised to explain prosocial behaviours towards the ingroup. The aim of this study is to test whether group heuristics similarly explain a reduction in antisocial behaviours towards the ingroup, measured by illegal consumption which harms a group that consumers identify with. In order to test corporate social responsibility messages, a population of interested consumers is required, so sport fans are recruited. A pre-registered experiment (N = 600) tests the influence of a focused “team” benefiting message vs a broader “sport” benefiting message on change in illegal intentions. The influence of group (team) identity and trait reciprocity on message efficacy are tested as measures of group heuristics. Results suggest that the “team” treatment significantly reduces illegal consumption intentions. The “sport” treatment interacted with the team identification measure, increasing illegal consumption intentions for low team identification individuals. The results suggest that corporate social responsibility may be effective in reducing illegal consumption, if the messages are delivered directly from brands to consumers with brand identification. Messages delivered on the behalf of an industry may have an undesirable effect.

Keywords: live sports, piracy, counterfeiting, corporate social responsibility, group heuristics, ingroup bias, team identification

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3170 Examining the Structural Model of Mindfulness and Headache Intensity With the Mediation of Resilience and Perfectionism in Migraine Patients

Authors: Alireza Monzavi Chaleshtari, Mahnaz Aliakbari Dehkordi, Nazila Esmaeili, Ahmad Alipour, Amin Asadi Hieh

Abstract:

Headache disorders are one of the most common disorders of the nervous system and are associated with suffering, disability, and financial costs for patients. Mindfulness as a lifestyle, in line with human nature, has the ability to affect the emotional system, i.e. thoughts, body sensations, raw emotions and action impulses of people. The aim of this study was to test the fit of structural model of mindfulness and severity of headache mediated by resilience and perfectionism in patients with migraine. Methods: The statistical population of this study included all patients with migraine referred to neurologists in Tehran in the spring and summer of 1401. The inclusion criteria were diagnosis of migraine by a neurologist, not having mental disorders or other physical diseases, and having at least a diploma. According to the number of research variables, 180 people were selected by convenience sampling method, which online answered the Ahvaz perfectionism questionnaire (AMQ), Connor and Davidson resilience questionnaire (CD-RISC), Ahvaz migraine headache questionnaire (APS) and 5-factor mindfulness questionnaire ((MAAS). Data were analyzed using structural equation modeling and Amos software. Results: The results showed that the direct pathways of mindfulness were not significant for severe headache (P <0.05), but other direct pathways - mindfulness to resilience, mindfulness to perfectionism, resilience to severe headache and perfectionism to severe headache), Was significant (P <0.01). After modifying and removing the non-significant paths, the final model fitted. Mediating variables Resilience and perfectionism mediated all paths of predictor variables to the criterion. Conclusion: According to the findings of the present study, mindfulness in migraine patients reduces the severity of headache by promoting resilience and reducing perfectionism.

Keywords: migraine, headache severity, mindfulness, resilience, perfectionism

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3169 Shape Management Method for Safety Evaluation of Bridge Based on Terrestrial Laser Scanning Using Least Squares

Authors: Gichun Cha, Dongwan Lee, Junkyeong Kim, Aoqi Zhang, Seunghee Park

Abstract:

All the world are studying the construction technology of double deck tunnel in order to respond to the increasing urban traffic demands and environmental changes. Advanced countries have the construction technology of the double deck tunnel structure. but the domestic country began research on it. Construction technologies are important. But Safety evaluation of structure is necessary to prevent possible accidents during construction. Thus, the double deck tunnel was required the shape management of middle slabs. The domestic country is preparing the construction of double deck tunnel for an alternate route and a pleasant urban environment. Shape management of double deck tunnel has been no research because it is a new attempted technology. The present, a similar study is bridge structure for the shape management. Bridge is implemented shape model using terrestrial laser scanning(TLS). Therefore, we proceed research on the bridge slabs because there is a similar structure of double deck tunnel. In the study, we develop shape management method of bridge slabs using TLS. We select the Test-bed for measurement site. This site is bridge located on Sungkyunkwan University Natural Sciences Campus. This bridge has a total length of 34m, the vertical height of 8.7m from the ground. It connects Engineering Building #1 and Engineering Building #2. Point cloud data for shape management is acquired the TLS and We utilized the Leica ScanStation C10/C5 model. We will confirm the Maximum displacement area of middle slabs using Least-Squares Fitting. We expect to raise stability for double deck tunnel through shape management for middle slabs.

Keywords: bridge slabs, least squares, safety evaluation, shape management method, terrestrial laser scanning

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3168 An Organocatalytic Construction of Vicinal Tetrasubstituted Stereocenters via Mannich Reaction of 2-Substituted Benzofuran-3-One with Isatin-Derived Ketimine

Authors: Koilpitchai Sivamuthuraman, Venkitasamy Kesavan

Abstract:

3-substituted 3-amino-2-oxindole skeleton bearing adjacent tetrasubstituted stereogenic centers is of great importance because of these heterocyclic motifs possess a wide range of pharmacological activity. The catalytic asymmetric construction of multi functionalised heterocyclic compound with adjacent tetrasubstituted stereocenters is one of the most difficult tasks in organic synthesis. To date, the most straightforward methodologies have been developed for synthesis of chiral 3-substituted 3-amino-2-oxindoles through the addition of carbon nucleophiles to isatin-derived ketimines. However, only a few successful examples have been described for the assembly of vicinal tetrasubstituted stereocenters using isatin derived ketimines as electrophiles. On the other hand, 2,2-Disubstituted benzofuran-3(2H)-ones and related frameworks are characteristic of a quaternary stereogenic center at C2 position present in quite a number of natural products and bioactive Molecules.Despite the intensive efforts devoted for the construction of 2,2-Disubstituted Benzofuran-3[2H]-one, there are only a few asymmetric methods such as organocatalytic Michael addition and enantioselective halogenations were reported till now. Due to the biological importance of oxindole and benzofuran-3-one, it is proposed here with the synthesis of hybrid molecule containing tetrasubstituted stereo centers through asymmetric organocatalysis. The addition of 2-substituted Benzofuran-3-one(1a) to isatin-derived ketimines(2a) using a bifunctional organocatalyst(catalyst IV or V), leading to chiral heterocyclic compounds containing both 3-amino 2-oxindole and benzofurn-3-one bearing vicinal quaternary stereocenters with good yields and excellent enantioselectivity. The present study extends the scope of the catalytic asymmetric Mannich reaction with isatin-derived ketimines, providing a new class of amino oxindole derivatives having benzofuran-3-one.

Keywords: asymmetric synthesis, benzofuran-3-one, isatin-derived ketimines, quaternary stereocenters

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3167 Antifungal Susceptibility of Saprolegnia parasitica Isolated from Rainbow Trout and Its Host Pathogen Interaction in Zebrafish Disease Model

Authors: Sangyeop Shin, D. C. M. Kulatunga, S. H. S. Dananjaya, Chamilani Nikapitiya, Jehee Lee, Mahanama De Zoysa

Abstract:

Saprolegniasis is one of the most devastating fungal diseases in freshwater fish which is caused by species in the genus Saprolegnia including Saprolegnia parasitica. In this study, we isolated the strain of S. parasitica from diseased rainbow trout in Korea. Morphological and molecular based identification confirmed that isolated fungi belong to the member of S. parasitica, supported by its typical fungal features including cotton-like whitish mycelium, zoospores (primary and secondary) and phylogenetic analysis with internal transcribed spacer (ITS) region. Pathogenicity of isolated S. parasitica was developed in embryo, larvae, juvenile and adult zebrafish as a disease model. Up regulation of host genes encoding ZfTnf-α, Zfc-Rel, ZfIl-12, ZfLyz-c, Zfβ-def, and ZfHsp-70 was identified in zebrafish larvae after experimental challenge of S. parasitica showing the host immune responses against the S. parasitica. Survival of the juveniles upon fungal infection might be due to the increased immune protection in the host. Investigation of antifungal susceptibility of S. parasitica with natural lawsone (2-hydroxy-1,4-naphthoquinone) revealed the minimum inhibitory concentration (MIC) and percentage inhibition of radial growth (PIRG %) as 200 µg/mL and 31.8%, respectively. Lawsone was able to change the membrane permeability, and cause irreversible damage and disintegration to the cellular membranes of S. parasitica which might have effect on fungi growth inhibition. Moreover, the mycelium exposed to lawsone (MIC level) changed the transcriptional responses of S. parasitica genes. Overall results indicate that lawsone could be a potential and novel anti-S. parasitica agent for controlling S. parasitica infection.

Keywords: host-pathogen interactions, lawsone, rainbow trout, Saprolegnia parasitica, Saprolegniasis, zebrafish

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3166 The Ameliorative Effects of the Histamine H3 Receptor Antagonist/Inverse Agonist DL77 on MK801-Induced Memory Deficits in Rats

Authors: B. Sadek, N. Khan, Shreesh K. Ojha, Adel Sadeq, D. Lazewska, K. Kiec-Kononowicz

Abstract:

The involvement of Histamine H3 receptors (H3Rs) in memory and the potential role of H3R antagonists in pharmacological control of neurodegenerative disorders, e.g., Alzheimer disease (AD) is well established. Therefore, the memory-enhancing effects of the H3R antagonist DL77 on MK801-induced cognitive deficits were evaluated in passive avoidance paradigm (PAP) and novel object recognition (NOR) tasks in adult male rats, applying donepezil (DOZ) as a reference drug. Animals pretreated with acute systemic administration of DL77 (2.5, 5, and 10 mg/kg, i.p.) were significantly ameliorated in regard to MK801-induced memory deficits in PAP. The ameliorative effect of most effective dose of DL77 (5 mg/kg, i.p.) was abrogated when animals were pretreated with a co-injection with the H3R agonist R-(α)-methylhistamine (RAMH, 10 mg/kg, i.p.). Moreover, and in the NOR paradigm, DL77 (5 mg/kg, i.p.) reversed MK801-induced deficits long-term memory (LTM), and the DL77-provided procognitive effect was comparable to that of reference drug DOZ, and was reversed when animals were co-injected with RAMH (10 mg/kg, i.p.). However, DL77(5 mg/kg, i.p.) failed to alter short-term memory (STM) impairment in NOR test. Furthermore, DL77 (5 mg/kg) failed to induce any alterations of anxiety and locomotor behaviors of animals naive to elevated-plus maze (EPM), indicating that the ameliorative effects observed in PAP or NOR tests were not associated to alterations in emotions or in natural locomotion of tested animals. These results reveal the potential contribution of H3Rs in modulating CNS neurotransmission systems associated with neurodegenerative disorders, e.g., AD.

Keywords: histamine H3 receptor, antagonist, learning and memory, Alzheimer's disease, neurodegeneration, passive avoidance paradigm, novel object recognition, behavioral research

Procedia PDF Downloads 138