Search results for: large deviation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7957

Search results for: large deviation

1597 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

Procedia PDF Downloads 161
1596 Numerical Investigation of Embankments for Protecting Rock Fall

Authors: Gökhan Altay, Cafer Kayadelen

Abstract:

Rock fall is a movement of huge rock blocks from dip slopes due to physical effects. It generally occurs where loose tuffs lying under basalt flow or stringcourse is being constituted by limestone layers which stand on clay. By corrosion of some parts, big cracks occur on layers and these cracks continue to grow with the effect of freezing-thawing. In this way, the breaking rocks fall down from these dip slopes. Earthquakes which can induce lots of rock movements is another reason for rock fall events. In Turkey, we have a large number of regions prone to the earthquake as in the World so this increases the possibility of rock fall events. A great number of rock fall events take place in Turkey as in the World every year. The rock fall events occurring in urban areas cause serious damages in houses, roads and workplaces. Sometimes it also hinders transportation and furthermore it maybe kills people. In Turkey, rock fall events happen mostly in Spring and Winter because of freezing- thawing of water in rock cracks frequently. In mountain and inclined areas, rock fall is risky for engineering construction and environment. Some countries can invest significant money for these risky areas. For instance, in Switzerland, approximately 6.7 million dollars is spent annually for a distance of 4 km, to the systems to prevent rock fall events. In Turkey, we have lots of urban areas and engineering structure that have the rock fall risk. The embankments are preferable for rock fall events because of its low maintenance and repair costs. Also, embankments are able to absorb much more energy according to other protection systems. The current design method of embankments is only depended on field tests results so there are inadequate studies about this design method. In this paper, the field test modeled in three dimensions and analysis are carried out with the help of ANSYS programme. By the help of field test from literature the numerical model validated. After the validity of numerical models additional parametric studies performed. Changes in deformation of embankments are investigated by the changes in, geometry, velocity and impact height of falling rocks.

Keywords: ANSYS, embankment, impact height, numerical analysis, rock fall

Procedia PDF Downloads 509
1595 Humans’ Physical Strength Capacities on Different Handwheel Diameters and Angles

Authors: Saif K. Al-Qaisi, Jad R. Mansour, Aseel W. Sakka, Yousef Al-Abdallat

Abstract:

Handwheels are common to numerous industries, such as power generation plants, oil refineries, and chemical processing plants. The forces required to manually turn handwheels have been shown to exceed operators’ physical strengths, posing risks for injuries. Therefore, the objectives of this research were twofold: (1) to determine humans’ physical strengths on handwheels of different sizes and angles and (2) to subsequently propose recommended torque limits (RTLs) that accommodate the strengths of even the weaker segment of the population. Thirty male and thirty female participants were recruited from a university student population. Participants were asked to exert their maximum possible forces in a counter-clockwise direction on handwheels of different sizes (35 cm, 45 cm, 60 cm, and 70 cm) and angles (0°-horizontal, 45°-slanted, and 90°-vertical). The participant’s posture was controlled by adjusting the handwheel to be at the elbow level of each participant, requiring the participant to stand erect, and restricting the hand placements to be in the 10-11 o’clock position for the left hand and the 4-5 o’clock position for the right hand. A torque transducer (Futek TDF600) was used to measure the maximum torques generated by the human. Three repetitions were performed for each handwheel condition, and the average was computed. Results showed that, at all handwheel angles, as the handwheel diameter increased, the maximum torques generated also increased, while the underlying forces decreased. In controlling the handwheel diameter, the 0° handwheel was associated with the largest torques and forces, and the 45° handwheel was associated with the lowest torques and forces. Hence, a larger handwheel diameter –as large as 70 cm– in a 0° angle is favored for increasing the torque production capacities of users. Also, it was recognized that, regardless of the handwheel diameter size and angle, the torque demands in the field are much greater than humans’ torque production capabilities. As such, this research proposed RTLs for the different handwheel conditions by using the 25th percentile values of the females’ torque strengths. The proposed recommendations may serve future standard developers in defining torque limits that accommodate humans’ strengths.

Keywords: handwheel angle, handwheel diameter, humans’ torque production strengths, recommended torque limits

Procedia PDF Downloads 111
1594 The Persistence of Abnormal Return on Assets: An Exploratory Analysis of the Differences between Industries and Differences between Firms by Country and Sector

Authors: José Luis Gallizo, Pilar Gargallo, Ramon Saladrigues, Manuel Salvador

Abstract:

This study offers an exploratory statistical analysis of the persistence of annual profits across a sample of firms from different European Union (EU) countries. To this end, a hierarchical Bayesian dynamic model has been used which enables the annual behaviour of those profits to be broken down into a permanent structural and a transitory component, while also distinguishing between general effects affecting the industry as a whole to which each firm belongs and specific effects affecting each firm in particular. This breakdown enables the relative importance of those fundamental components to be more accurately evaluated by country and sector. Furthermore, Bayesian approach allows for testing different hypotheses about the homogeneity of the behaviour of the above components with respect to the sector and the country where the firm develops its activity. The data analysed come from a sample of 23,293 firms in EU countries selected from the AMADEUS data-base. The period analysed ran from 1999 to 2007 and 21 sectors were analysed, chosen in such a way that there was a sufficiently large number of firms in each country sector combination for the industry effects to be estimated accurately enough for meaningful comparisons to be made by sector and country. The analysis has been conducted by sector and by country from a Bayesian perspective, thus making the study more flexible and realistic since the estimates obtained do not depend on asymptotic results. In general terms, the study finds that, although the industry effects are significant, more important are the firm specific effects. That importance varies depending on the sector or the country in which the firm carries out its activity. The influence of firm effects accounts for around 81% of total variation and display a significantly lower degree of persistence, with adjustment speeds oscillating around 34%. However, this pattern is not homogeneous but depends on the sector and country analysed. Industry effects depends also on sector and country analysed have a more marginal importance, being significantly more persistent, with adjustment speeds oscillating around 7-8% with this degree of persistence being very similar for most of sectors and countries analysed.

Keywords: dynamic models, Bayesian inference, MCMC, abnormal returns, persistence of profits, return on assets

Procedia PDF Downloads 400
1593 Quantum Chemical Calculations on Molecular Structure, Spectroscopy and Non-Linear Optical Properties of Some Chalcone Derivatives

Authors: Archana Gupta, Rajesh Kumar

Abstract:

The chemistry of chalcones has generated intensive scientific studies throughout the world. Especially, interest has been focused on the synthesis and biodynamic activities of chalcones. The blue light transmittance, excellent crystallizability and the two planar rings connected through a conjugated double bond show that chalcone derivatives are superior nonlinear organic compounds. 3-(2-Chloro-6-fluoro¬phen¬yl)-1-(2-thien¬yl) prop-2-en-1-one, 3-(2, 4- Dichlorophenyl) – 1 - (4-methylphenyl) – prop -2-en-1-one, (2E)-3-[4-(methylsulfanyl) phenyl]-1-(4-nitrophenyl) prop-2-en-1-one are some chalcone derivatives exhibiting non linear optical (NLO) properties. NLO materials have been extensively investigated in recent years as they are the key elements for photonic technologies of optical communication, optical interconnect oscillator, amplifier, frequency converter etc. Due to their high molecular hyperpolarizabilities, organic materials display a number of significant NLO properties. Experimental measurements and theoretical calculations on molecular hyperpolarizability β have become one of the key factors in the design of second order NLO materials. Theoretical determination of hyperpolarizability is quite useful both in understanding the relationship between the molecular structure and NLO properties. It also provides a guideline to experimentalists for the design and synthesis of organic NLO materials. Quantum-chemical calculations have made an important contribution to the understanding of the electronic polarization underlying the molecular NLO processes and the establishment of structure–property relationships. In the present investigation, the detailed vibrational analysis of some chalcone derivatives is taken up to understand the correlation of the charge transfer interaction and the NLO activity of the molecules based on density functional theory calculations. The vibrational modes contributing toward the NLO activity have been identified and analyzed. Rather large hyperpolarizability derived by theoretical calculations suggests the possible future use of these compounds for non-linear optical applications. The study suggests the importance of π - conjugated systems for non-linear optical properties and the possibility of charge transfer interactions. We hope that the results of the present study of chalcone derivatives are of assistance in development of new efficient materials for technological applications.

Keywords: hyperpolarizability, molecular structure, NLO material, quantum chemical calculations

Procedia PDF Downloads 233
1592 National Assessment for Schools in Saudi Arabia: Score Reliability and Plausible Values

Authors: Dimiter M. Dimitrov, Abdullah Sadaawi

Abstract:

The National Assessment for Schools (NAFS) in Saudi Arabia consists of standardized tests in Mathematics, Reading, and Science for school grade levels 3, 6, and 9. One main goal is to classify students into four categories of NAFS performance (minimal, basic, proficient, and advanced) by schools and the entire national sample. The NAFS scoring and equating is performed on a bounded scale (D-scale: ranging from 0 to 1) in the framework of the recently developed “D-scoring method of measurement.” The specificity of the NAFS measurement framework and data complexity presented both challenges and opportunities to (a) the estimation of score reliability for schools, (b) setting cut-scores for the classification of students into categories of performance, and (c) generating plausible values for distributions of student performance on the D-scale. The estimation of score reliability at the school level was performed in the framework of generalizability theory (GT), with students “nested” within schools and test items “nested” within test forms. The GT design was executed via a multilevel modeling syntax code in R. Cut-scores (on the D-scale) for the classification of students into performance categories was derived via a recently developed method of standard setting, referred to as “Response Vector for Mastery” (RVM) method. For each school, the classification of students into categories of NAFS performance was based on distributions of plausible values for the students’ scores on NAFS tests by grade level (3, 6, and 9) and subject (Mathematics, Reading, and Science). Plausible values (on the D-scale) for each individual student were generated via random selection from a statistical logit-normal distribution with parameters derived from the student’s D-score and its conditional standard error, SE(D). All procedures related to D-scoring, equating, generating plausible values, and classification of students into performance levels were executed via a computer program in R developed for the purpose of NAFS data analysis.

Keywords: large-scale assessment, reliability, generalizability theory, plausible values

Procedia PDF Downloads 17
1591 An Approach to Determine Proper Daylighting Design Solution Considering Visual Comfort and Lighting Energy Efficiency in High-Rise Residential Building

Authors: Zehra Aybike Kılıç, Alpin Köknel Yener

Abstract:

Daylight is a powerful driver in terms of improving human health, enhancing productivity and creating sustainable solutions by minimizing energy demand. A proper daylighting system allows not only a pleasant and attractive visual and thermal environment, but also reduces lighting energy consumption and heating/cooling energy load with the optimization of aperture size, glazing type and solar control strategy, which are the major design parameters of daylighting system design. Particularly, in high-rise buildings where large openings that allow maximum daylight and view out are preferred, evaluation of daylight performance by considering the major parameters of the building envelope design becomes crucial in terms of ensuring occupants’ comfort and improving energy efficiency. Moreover, it is increasingly necessary to examine the daylighting design of high-rise residential buildings, considering the share of residential buildings in the construction sector, the duration of occupation and the changing space requirements. This study aims to identify a proper daylighting design solution considering window area, glazing type and solar control strategy for a high-residential building in terms of visual comfort and lighting energy efficiency. The dynamic simulations are carried out/conducted by DIVA for Rhino version 4.1.0.12. The results are evaluated with Daylight Autonomy (DA) to demonstrate daylight availability in the space and Daylight Glare Probability (DGP) to describe the visual comfort conditions related to glare. Furthermore, it is also analyzed that the lighting energy consumption occurred in each scenario to determine the optimum solution reducing lighting energy consumption by optimizing daylight performance. The results revealed that it is only possible that reduction in lighting energy consumption as well as providing visual comfort conditions in buildings with the proper daylighting design decision regarding glazing type, transparency ratio and solar control device.

Keywords: daylighting , glazing type, lighting energy efficiency, residential building, solar control strategy, visual comfort

Procedia PDF Downloads 174
1590 Germany – Pakistan Relations (1960 – 2015): An Analytical Study

Authors: Wahid Sharif

Abstract:

Germany is a country that is traditionally highly regarded in the countries of South Asia. The German people and German products are valued and generate a positive response in South Asia. The main objective of this research is to evaluate and analyze various dimensions of a Such Comparative Study of Geography (German & Pakistan). Basically, Germany is located in Central Europe; it has common borders with Denmark, the Netherlands, Belgium, Luxembourg, France, Switzerland, Austria, the Czech Republic and Poland, Its total area is around 356,854 sq km. Pakistan has a strategic geo-political location at the corridor of the world's major maritime oil supply lines and has close proximity to the resource and oil-rich Central Asian countries. Germany and Pakistan enjoy intimately cordial relations. Germany has taken large measures to aid the south Asian countries in its economic and governmental hardship. Commercial trade between Berlin and Islamabad has also been essential as Germany is Pakistan’s fourth largest trade partner, also Germany is home to 35,081 Pakistani immigrants overall, and the two nations have almost always had a friendly bond. The aim of this research is to initiate fruitful discussions about appropriate strategies and actions in the face of the economic and geopolitical challenges faced by Pakistan and the role that societies of each country can play in assisting the region in overcoming its problems. The research would aim to serve as a facilitator for developing collaborative research projects between different institutions and disciplines in the Germany and Pakistan institutions. This is important, as the issues of poverty, illiteracy, unemployment and social inequities need to be understood properly. Though geographically far apart from each other and not having gone through the experience that the Asian states had undergone in their relations with the Portuguese, Dutch, French and English. Pakistan and Germany did not have to forget any unpleasant memories of a colonial past. On the contrary, the freedom fighters of the Indo-Pak subcontinent did not make secret of their sympathy-nay-admiration for Germany, which, though defeated in World War I and World War II by Anglo-French and Anglo-American blocs respectively, had shaken the British and French empires to their foundation in the protracted wars.

Keywords: relations, cultural, socio economic, bilateral agreement

Procedia PDF Downloads 37
1589 A Traditional Settlement in a Modernized City: Yanbu, Saudi Arabia

Authors: Hisham Mortada

Abstract:

Transition in the urban configuration of Arab cities has never been as radical and visible as it has been since the turn of the last century. The emergence of new cities near historical settlements of Arabia has spawned a series of developments in and around the old city precincts. New developments are based on advanced technology and conform to globally prevalent standards of city planning, superseding the vernacular arrangements based on traditional norms that guided so-called ‘city planning’. Evidence to this fact are the extant Arab buildings present at the urban core of modern cities, which inform us about intricate spatial organization. Organization that subscribed to multiple norms such as, satisfying gender segregation and socialization, economic sustainability, and ensuring security and environmental coherence etc., within settlement compounds. Several participating factors achieved harmony in such an inclusive city—an organization that was challenged and apparently replaced by the new planning order in the face of growing needs of globalized, economy-centric and high-tech models of development. Communities found it difficult to acclimatize with the new western planning models that were implemented at a very large scale throughout the Kingdom, which later experienced spatial re-structuring to suit users’ needs. A closer look the ancient city of Yanbu, now flanked with such new developments, allows us to differentiate and track the beginnings of this unprecedented transition in settlement formations. This paper aims to elaborate the Arabian context offered to both the ‘traditional’ and ‘modern’ planning approaches, in order to understand challenges and solutions offered by both at different times. In the process it will also establish the inconsistencies and conflicts that arose with the shift in planning paradigm, from traditional-'cultural norms’, to modern-'physical planning', in the Arabian context. Thus, by distinguishing the two divergent planning philosophies, their impact of the Arabian morphology, relevance to lifestyle and suitability to the biophysical environment, it concludes with a perspective on sustainability particularly for in case of Yanbu.

Keywords: Yanbu, traditional architecture, Hijaz, coral building, Saudi Arabia

Procedia PDF Downloads 320
1588 Investigating Salience Theory’s Implications for Real-Life Decision Making: An Experimental Test for Whether the Allais Paradox Exists under Subjective Uncertainty

Authors: Christoph Ostermair

Abstract:

We deal with the effect of correlation between prospects on human decision making under uncertainty as proposed by the comparatively new and promising model of “salience theory of choice under risk”. In this regard, we show that the theory entails the prediction that the inconsistency of choices, known as the Allais paradox, should not be an issue in the context of “real-life decision making”, which typically corresponds to situations of subjective uncertainty. The Allais paradox, probably the best-known anomaly regarding expected utility theory, would then essentially have no practical relevance. If, however, empiricism contradicts this prediction, salience theory might suffer a serious setback. Explanations of the model for variable human choice behavior are mostly the result of a particular mechanism that does not come to play under perfect correlation. Hence, if it turns out that correlation between prospects – as typically found in real-world applications – does not influence human decision making in the expected way, this might to a large extent cost the theory its explanatory power. The empirical literature regarding the Allais paradox under subjective uncertainty is so far rather moderate. Beyond that, the results are hard to maintain as an argument, as the presentation formats commonly employed, supposably have generated so-called event-splitting effects, thereby distorting subjects’ choice behavior. In our own incentivized experimental study, we control for such effects by means of two different choice settings. We find significant event-splitting effects in both settings, thereby supporting the suspicion that the so far existing empirical results related to Allais paradoxes under subjective uncertainty may not be able to answer the question at hand. Nevertheless, we find that the basic tendency behind the Allais paradox, which is a particular switch of the preference relation due to a modified common consequence, shared by two prospects, is still existent both under an event-splitting and a coalesced presentation format. Yet, the modal choice pattern is in line with the prediction of salience theory. As a consequence, the effect of correlation, as proposed by the model, might - if anything - only weaken the systematic choice pattern behind the Allais paradox.

Keywords: Allais paradox, common consequence effect, models of decision making under risk and uncertainty, salience theory

Procedia PDF Downloads 196
1587 Prefabrication Technology as an Option for Accelerated Sustainable Social Housing Delivery in South Africa

Authors: Madifedile Thasi, Azola Mayeza

Abstract:

In South Africa, provision of housing to the growing population has been described as one of the greatest challenges facing the government. Between 1994 to 2015, more than 2.5 million housing units were provided by the government for the poorest households and the low-income earners under the Reconstruction and Development Programme (RDP). Yet, the latest census figure revealed that about 2.1 million households still live in shacks and informal dwellings. Human settlements patterns remain dysfunctional across in South Africa because of rapid urbanisation. The housing backlog is growing at a rate of 178 000 units a year. The aforementioned predicament calls the need for innovative approaches to address the issue in a sustainable way and this need not be overemphasized. Aside from the issue of cost, the delivery of more housing units comes with environmental and sustainability issues. The prefabrication building technology has resulted into accelerated housing delivery to a satisfactory level in some countries such as Nigeria and Malaysia that are facing similar issue. It is therefore expected to be a foremost option to address the social housing backlog in South Africa and within the country housing sustainability agenda. This paper appraises the factors responsible for the limited implementation of prefabrication technology in South African housing projects. The objective is to recommend the method and materials that can be best sustained in the country in terms of local availability, cost effectiveness and environmental friendliness. It presents empirical data to support the hypothesis that a wider implementation of prefabrication technology in the social housing projects will be of significant benefit, by providing fast turnaround, cost-effective and sustainable solution that will dent the housing backlog, as well as improving the quality of the social housings. It was found that only 17 000 units of the RDP housings provided were constructed using alternative building technologies. Furthermore, there are variety of prefabricated technologies in the market but mostly have limited production capacity, minimal manufacturing capacity and most materials are imported, which leads to unavailability of the technology for large scale delivery and utilization despite its obvious advantages.

Keywords: prefabrication technology, sustainable social housings, South Africa, housing delivery

Procedia PDF Downloads 207
1586 Osteoporosis and Weight Gain – Two Major Concerns for Menopausal Women - a Physiotherapy Perspective

Authors: Renu Pattanshetty

Abstract:

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 301
1585 Recirculated Sedimentation Method to Control Contamination for Algal Biomass Production

Authors: Ismail S. Bostanci, Ebru Akkaya

Abstract:

Microalgae-derived biodiesel, fertilizer or industrial chemicals' production with wastewater has great potential. Especially water from a municipal wastewater treatment plant is a very important nutrient source for biofuel production. Microalgae biomass production in open ponds system is lower cost culture systems. There are many hurdles for commercial algal biomass production in large scale. One of the important technical bottlenecks for microalgae production in open system is culture contamination. The algae culture contaminants can generally be described as invading organisms which could cause pond crash. These invading organisms can be competitors, parasites, and predators. Contamination is unavoidable in open systems. Potential contaminant organisms are already inoculated if wastewater is utilized for algal biomass cultivation. Especially, it is important to control contaminants to retain in acceptable level in order to reach true potential of algal biofuel production. There are several contamination management methods in algae industry, ranging from mechanical, chemical, biological and growth condition change applications. However, none of them are accepted as a suitable contamination control method. This experiment describes an innovative contamination control method, 'Recirculated Sedimentation Method', to manage contamination to avoid pond cash. The method can be used for the production of algal biofuel, fertilizer etc. and algal wastewater treatment. To evaluate the performance of the method on algal culture, an experiment was conducted for 90 days at a lab-scale raceway (60 L) reactor with the use of non-sterilized and non-filtered wastewater (secondary effluent and centrate of anaerobic digestion). The application of the method provided the following; removing contaminants (predators and diatoms) and other debris from reactor without discharging the culture (with microscopic evidence), increasing raceway tank’s suspended solids holding capacity (770 mg L-1), increasing ammonium removal rate (29.83 mg L-1 d-1), decreasing algal and microbial biofilm formation on inner walls of reactor, washing out generated nitrifier from reactor to prevent ammonium consumption.

Keywords: contamination control, microalgae culture contamination, pond crash, predator control

Procedia PDF Downloads 206
1584 Neuroevolution Based on Adaptive Ensembles of Biologically Inspired Optimization Algorithms Applied for Modeling a Chemical Engineering Process

Authors: Sabina-Adriana Floria, Marius Gavrilescu, Florin Leon, Silvia Curteanu, Costel Anton

Abstract:

Neuroevolution is a subfield of artificial intelligence used to solve various problems in different application areas. Specifically, neuroevolution is a technique that applies biologically inspired methods to generate neural network architectures and optimize their parameters automatically. In this paper, we use different biologically inspired optimization algorithms in an ensemble strategy with the aim of training multilayer perceptron neural networks, resulting in regression models used to simulate the industrial chemical process of obtaining bricks from silicone-based materials. Installations in the raw ceramics industry, i.e., bricks, are characterized by significant energy consumption and large quantities of emissions. In addition, the initial conditions that were taken into account during the design and commissioning of the installation can change over time, which leads to the need to add new mixes to adjust the operating conditions for the desired purpose, e.g., material properties and energy saving. The present approach follows the study by simulation of a process of obtaining bricks from silicone-based materials, i.e., the modeling and optimization of the process. Optimization aims to determine the working conditions that minimize the emissions represented by nitrogen monoxide. We first use a search procedure to find the best values for the parameters of various biologically inspired optimization algorithms. Then, we propose an adaptive ensemble strategy that uses only a subset of the best algorithms identified in the search stage. The adaptive ensemble strategy combines the results of selected algorithms and automatically assigns more processing capacity to the more efficient algorithms. Their efficiency may also vary at different stages of the optimization process. In a given ensemble iteration, the most efficient algorithms aim to maintain good convergence, while the less efficient algorithms can improve population diversity. The proposed adaptive ensemble strategy outperforms the individual optimizers and the non-adaptive ensemble strategy in convergence speed, and the obtained results provide lower error values.

Keywords: optimization, biologically inspired algorithm, neuroevolution, ensembles, bricks, emission minimization

Procedia PDF Downloads 114
1583 Women’s Empowerment on Modern Contraceptive Use in Poor-Rich Segment of Population: Evidence from South Asian Countries

Authors: Muhammad Asim

Abstract:

Background: Less than half of women in South Asia (SA) use any modern contraceptive method which leads to a huge burden of unintended pregnancies, unsafe abortions, maternal deaths, and socioeconomic loss. Women empowerment plays a pivotal role in improving various health seeking behaviours, including contraceptive use. The objective of this study to explore the association between women's empowerment and modern contraceptive, among rich and poor segment of population in SA. Methods: We used the most recent, large-scale, demographic health survey data of five South Asian countries, namely Afghanistan, Pakistan, Bangladesh, India, and Nepal. The outcome variable was the current use of modern contraceptive methods. The main exposure variable was a combination (interaction) of socio-economic status (SES) and women’s level of empowerment (low, medium, and high), where SES was bifurcated into poor and rich; and women empowerment was divided into three categories: decision making, attitude to violence and social independence. Moreover, overall women empowerment indicator was also created by using three dimensions of women empowerment. We applied both descriptive statistics and multivariable logistic regression techniques for data analyses. Results: Most of the women possessed ‘medium’ level of empowerment across South Asian Countries. The lowest attitude to violence empowerment was found in Afghanistan, and the lowest social independence empowerment was observed in Bangladesh across SA. However, Pakistani women have the lowest decision-making empowerment in the region. The lowest modern contraceptive use (22.1%) was found in Afghanistan and the highest (53.2%) in Bangladesh. The multivariate results depict that the overall measure of women empowerment does not affect modern contraceptive use among poor and rich women in most of South Asian countries. However, the decision-making empowerment plays a significant role among both poor and rich women to use modern contraceptive methods across South Asian countries. Conclusions: The effect of women’s empowerment on modern contraceptive use is not consistent across countries, and among poor and rich segment of population. Of the three dimensions of women’s empowerment, the autonomy of decision making in household affairs emerged as a stronger determinant of mCPR as compared with social independence and attitude towards violence against women.

Keywords: women empowerment, contraceptive use, South Asia, women autonomy

Procedia PDF Downloads 85
1582 Critical Parameters of a Square-Well Fluid

Authors: Hamza Javar Magnier, Leslie V. Woodcock

Abstract:

We report extensive molecular dynamics (MD) computational investigations into the thermodynamic description of supercritical properties for a model fluid that is the simplest realistic representation of atoms or molecules. The pair potential is a hard-sphere repulsion of diameter σ with a very short attraction of length λσ. When λ = 1.005 the range is so short that the model atoms are referred to as “adhesive spheres”. Molecular dimers, trimers …etc. up to large clusters, or droplets, of many adhesive-sphere atoms are unambiguously defined. This then defines percolation transitions at the molecular level that bound the existence of gas and liquid phases at supercritical temperatures, and which define the existence of a supercritical mesophase. Both liquid and gas phases are seen to terminate at the loci of percolation transitions, and below a second characteristic temperature (Tc2) are separated by the supercritical mesophase. An analysis of the distribution of clusters in gas, meso- and liquid phases confirms the colloidal nature of this mesophase. The general phase behaviour is compared with both experimental properties of the water-steam supercritical region and also with formally exact cluster theory of Mayer and Mayer. Both are found to be consistent with the present findings that in this system the supercritical mesophase narrows in density with increasing T > Tc and terminates at a higher Tc2 at a confluence of the primary percolation loci. The expended plot of the MD data points in the mesophase of 7 critical and supercritical isotherms in highlight this narrowing in density of the linear-slope region of the mesophase as temperature is increased above the critical. This linearity in the mesophase implies the existence of a linear combination rule between gas and liquid which is an extension of the Lever rule in the subcritical region, and can be used to obtain critical parameters without resorting to experimental data in the two-phase region. Using this combination rule, the calculated critical parameters Tc = 0.2007 and Pc = 0.0278 are found be agree with the values found by of Largo and coworkers. The properties of this supercritical mesophase are shown to be consistent with an alternative description of the phenomenon of critical opalescence seen in the supercritical region of both molecular and colloidal-protein supercritical fluids.

Keywords: critical opalescence, supercritical, square-well, percolation transition, critical parameters.

Procedia PDF Downloads 520
1581 A Focused, High-Intensity Spread-Spectrum Ultrasound Solution to Prevent Biofouling

Authors: Alan T. Sassler

Abstract:

Biofouling is a significant issue for ships, especially those based in warm water ports. Biofouling damages hull coatings, degrades platform hydrodynamics, blocks cooling water intakes, and returns, reduces platform range and speed, and increases fuel consumption. Although platforms are protected to some degree by antifouling paints, these paints are much less effective on stationary platforms, and problematic biofouling can occur on antifouling paint-protected stationary platforms in some environments in as little as a matter of weeks. Remediation hull cleaning operations are possible, but they are very expensive, sometimes result in damage to the vessel’s paint or hull and are generally not completely effective. Ultrasound with sufficient intensity focused on specific frequency ranges can be used to prevent the growth of biofouling organisms. The use of ultrasound to prevent biofouling isn't new, but systems to date have focused on protecting platforms by shaking the hull using internally mounted transducers similar to those used in ultrasonic cleaning machines. While potentially effective, this methodology doesn't scale well to large platforms, and there are significant costs associated with installing and maintaining these systems, which dwarf the initial purchase price. An alternative approach has been developed, which uses highly directional pier-mounted transducers to project high-intensity spread-spectrum ultrasonic energy into the water column focused near the surface. This focused energy has been shown to prevent biofouling at ranges of up to 50 meters from the source. Spreading the energy out over a multi-kilohertz band makes the system both more effective and more environmentally friendly. This system has been shown to be both effective and inexpensive in small-scale testing and is now being characterized on a larger scale in selected marinas. To date, test results have been collected in Florida marinas suggesting that this approach can be used to keep ensonified areas of thousands of square meters free from biofouling, although care must be taken to minimize shaded areas.

Keywords: biofouling, ultrasonic, environmentally friendly antifoulant, marine protection, antifouling

Procedia PDF Downloads 59
1580 Going Viral: Expanding a Student-Run COVID-19 Journal Club to Social Media

Authors: Joseph Dodson, Robert Roth, Alexander Hodakowski, Leah Greenfield, Melissa Porterhouse, Natalie Maltby, Rachel Sadowsky

Abstract:

Introduction: Throughout the COVID-19 pandemic, countless research publications were released regarding SARS-CoV-2 and its variants, suggested treatments, and vaccine safety and efficacy. Daily publication of research became overwhelming for health professionals and the general public to stay informed. To address this problem, a group of 70 students across the four colleges at Rush University created the “Rush University COVID-19 Journal Club.” To broaden the available audience, the journal club then expanded to social media. Methods: Easily accessible and understandable summaries of the research were written by students and sent to faculty sponsors for feedback. Following the revision, summaries were published weekly on the Rush University COVID-19 Journal Club website for clinicians and students to use for reference. An Instagram page was then created, and information was further condensed into succinct posts to address COVID-19 “FAQs.” Next, a survey was distributed to followers of the Instagram page with questions meant to assess the effectiveness of the platform and gain feedback. A 5-point Likert scale was used as the primary question format. Results: The Instagram page accrued 749 followers and posted 52 unique posts over a 2 year period. Preliminary results from the surveys demonstrate that over 80% of respondents strongly agree that the Instagram posts 1) are an effective platform for the public presentation of factual COVID-19-related information; 2) provide relevant and valuable information; 3) provide information that is clear, concise, and can be easily understood. Conclusion: These results suggest that the Rush COVID-19 Journal Club was able to successfully create a social media presence and convey information without sacrificing scholarly integrity. Other academic institutions may benefit from the application of this model to help students and clinicians with the interpretation and evaluation of research topics with large bodies of evidence.

Keywords: SARS-CoV-2, COVID-19, public health, social media, SARS-CoV-2 vaccine, SARS-CoV-2 variants

Procedia PDF Downloads 127
1579 Exploring Polypnenolics Content and Antioxidant Activity of R. damascena Dry Extract by Spectroscopic and Chromatographic Techniques

Authors: Daniela Nedeltcheva-Antonova, Kamelia Getchovska, Vera Deneva, Stanislav Bozhanov, Liudmil Antonov

Abstract:

Rosa damascena Mill. (Damask rose) is one of the most important plants belonging to the Rosaceae family, with a long historical use in traditional medicine and as a valuable oil-bearing plant. Many pharmacological effects have been reported from this plant, including anti-inflammatory, hypnotic, analgesic, anticonvulsant, anti-depressant, antianxiety, antitussive, antidiabetic, relaxant effects on tracheal chains, laxative, prokinetic and hepatoprotective activities. Pharmacological studies have shown that the various health effects of R. damascena flowers can mainly be attributed to its large amount of polyphenolic components. Phenolics possess a wide range of pharmacological activities, such as antioxidants, free-radical scavengers, anticancer, anti-inflammatory, antimutagenic, and antidepressant, with flavonoids being the most numerous group of natural polyphenolic compounds. According to the technological process in the production of rose concrete (solvent extraction with non-polar solvents of fresh rose flowers), it can be assumed that the resulting plant residue would be as rich of polyphenolics, as the plant itself, and could be used for the development of novel products with promising health-promoting effect. Therefore, an optimisation of the extraction procedure of the by-product from the rose concrete production was carried out. An assay of the extracts in respect of their total polyphenols and total flavonoids content was performed. HPLC analysis of quercetin and kaempferol, the two main flavonoids found in R. damascena, was also carried out. The preliminary results have shown that the flavonoid content in the rose extracts is comparable to that of the green tea or Gingko biloba, and they could be used for the development of various products (food supplements, natural cosmetics and phyto-pharmaceutical formulation, etc.). The fact that they are derived from the by-product of industrial plant processing could add the marketing value of the final products in addition to the well-known reputation of the products obtained from Bulgarian roses (R. damascena Mill.).

Keywords: gas chromatography-mass-spectromrtry, dry extract, flavonoids, Rosa damascena Mill

Procedia PDF Downloads 150
1578 Microbial Dark Matter Analysis Using 16S rRNA Gene Metagenomics Sequences

Authors: Hana Barak, Alex Sivan, Ariel Kushmaro

Abstract:

Microorganisms are the most diverse and abundant life forms on Earth and account for a large portion of the Earth’s biomass and biodiversity. To date though, our knowledge regarding microbial life is lacking, as it is based mainly on information from cultivated organisms. Indeed, microbiologists have borrowed from astrophysics and termed the ‘uncultured microbial majority’ as ‘microbial dark matter’. The realization of how diverse and unexplored microorganisms are, actually stems from recent advances in molecular biology, and in particular from novel methods for sequencing microbial small subunit ribosomal RNA genes directly from environmental samples termed next-generation sequencing (NGS). This has led us to use NGS that generates several gigabases of sequencing data in a single experimental run, to identify and classify environmental samples of microorganisms. In metagenomics sequencing analysis (both 16S and shotgun), sequences are compared to reference databases that contain only small part of the existing microorganisms and therefore their taxonomy assignment may reveal groups of unknown microorganisms or origins. These unknowns, or the ‘microbial sequences dark matter’, are usually ignored in spite of their great importance. The goal of this work was to develop an improved bioinformatics method that enables more complete analyses of the microbial communities in numerous environments. Therefore, NGS was used to identify previously unknown microorganisms from three different environments (industrials wastewater, Negev Desert’s rocks and water wells at the Arava valley). 16S rRNA gene metagenome analysis of the microorganisms from those three environments produce about ~4 million reads for 75 samples. Between 0.1-12% of the sequences in each sample were tagged as ‘Unassigned’. Employing relatively simple methodology for resequencing of original gDNA samples through Sanger or MiSeq Illumina with specific primers, this study demonstrates that the mysterious ‘Unassigned’ group apparently contains sequences of candidate phyla. Those unknown sequences can be located on a phylogenetic tree and thus provide a better understanding of the ‘sequences dark matter’ and its role in the research of microbial communities and diversity. Studying this ‘dark matter’ will extend the existing databases and could reveal the hidden potential of the ‘microbial dark matter’.

Keywords: bacteria, bioinformatics, dark matter, Next Generation Sequencing, unknown

Procedia PDF Downloads 255
1577 Translation of Scientific and Technological Terms into Hausa Language: A Guide to Hausa Language Translator in an Electronic Media (Radio)

Authors: Surajo Ladan

Abstract:

There is no doubt nowadays, the media plays a crucial role in the development of languages. Media practitioners influence and set our linguistic norms to a greater extent. Their strategic position makes them influential than school teachers as linguistic pacesetters and models. This is so because of the direct access to the general public that media enjoys being public, oriented and at the same time being patronized by the public, the media is regarded as an authority as far as language use is concerned. In the modern world, listening to the news has become part and parcel of our daily lives. Easy communication has made the world a global village. Contact between countries and people are increasing daily. In Nigeria and indeed the whole of West Africa, radio is the most widely spread out of the three types of media (radio, television, and print). This is because of its (radio) cheapness and less cumbersome and flexibility. Therefore, the positive or negative effect of radio on the lives of a typical Nigerian or African cannot be over emphasized. Hausa language, on the other hand, is one of the most widely spoken languages in West Africa and, of course, the lingua franca in the Northern part of Nigeria and Southern Niger. The language has been in use to a large extent by almost all the popular foreign media houses of BBC, VOA, Deutsche Welle Radio, Radio France International, Radio China, etc. The many people in Nigeria and West Africa depend so much on the news in this language. In fact even government programmes, mobilization, education and sensitization of the populace are done in this language through the broadcast media. It is against this background, for effective and efficient work of this nature it requires the services of a trained translator for the purpose of translating scientific and technological terms. The main thrust of this paper was necessitated for the fact that no nation develops using foreign or borrowed language. This is in lined with UNESCO declaration of 1953 where it says 'the best Language of Instruction (LOI) is the vernacular or the Mother Tongue (MT) of the learner'. This idea is in the right direction especially nowadays that the developing nations have come to terms with realities that their destiny is really in their own hands, not in the hands of the so-called developed nations.

Keywords: translation, scientific, technological, language, radio, media

Procedia PDF Downloads 374
1576 Short Life Cycle Time Series Forecasting

Authors: Shalaka Kadam, Dinesh Apte, Sagar Mainkar

Abstract:

The life cycle of products is becoming shorter and shorter due to increased competition in market, shorter product development time and increased product diversity. Short life cycles are normal in retail industry, style business, entertainment media, and telecom and semiconductor industry. The subject of accurate forecasting for demand of short lifecycle products is of special enthusiasm for many researchers and organizations. Due to short life cycle of products the amount of historical data that is available for forecasting is very minimal or even absent when new or modified products are launched in market. The companies dealing with such products want to increase the accuracy in demand forecasting so that they can utilize the full potential of the market at the same time do not oversupply. This provides the challenge to develop a forecasting model that can forecast accurately while handling large variations in data and consider the complex relationships between various parameters of data. Many statistical models have been proposed in literature for forecasting time series data. Traditional time series forecasting models do not work well for short life cycles due to lack of historical data. Also artificial neural networks (ANN) models are very time consuming to perform forecasting. We have studied the existing models that are used for forecasting and their limitations. This work proposes an effective and powerful forecasting approach for short life cycle time series forecasting. We have proposed an approach which takes into consideration different scenarios related to data availability for short lifecycle products. We then suggest a methodology which combines statistical analysis with structured judgement. Also the defined approach can be applied across domains. We then describe the method of creating a profile from analogous products. This profile can then be used for forecasting products with historical data of analogous products. We have designed an application which combines data, analytics and domain knowledge using point-and-click technology. The forecasting results generated are compared using MAPE, MSE and RMSE error scores. Conclusion: Based on the results it is observed that no one approach is sufficient for short life-cycle forecasting and we need to combine two or more approaches for achieving the desired accuracy.

Keywords: forecast, short life cycle product, structured judgement, time series

Procedia PDF Downloads 358
1575 Women’s Empowerment on Modern Contraceptive Use in Poor-Rich Segment of Population: Evidence From South Asian Countries

Authors: Muhammad Asim

Abstract:

Background: Less than half of women in South Asia (SA) use any modern contraceptive method which leads to a huge burden of unintended pregnancies, unsafe abortions, maternal deaths, and socioeconomic loss. Women empowerment plays a pivotal role in improving various health seeking behaviours, including contraceptive use. The objective of this study to explore the association between women's empowerment and modern contraceptive, among rich and poor segment of population in SA. Methods: We used the most recent, large-scale, demographic health survey data of five South Asian countries, namely Afghanistan, Pakistan, Bangladesh, India, and Nepal. The outcome variable was the current use of modern contraceptive methods. The main exposure variable was a combination (interaction) of socio-economic status (SES) and women’s level of empowerment (low, medium, and high), where SES was bifurcated into poor and rich; and women empowerment was divided into three categories: decision making, attitude to violence and social independence. Moreover, overall women empowerment indicator was also created by using three dimensions of women empowerment. We applied both descriptive statistics and multivariable logistic regression techniques for data analyses. Results: Most of the women possessed ‘medium’ level of empowerment across South Asian Countries. The lowest attitude to violence empowerment was found in Afghanistan, and the lowest social independence empowerment was observed in Bangladesh across SA. However, Pakistani women have the lowest decision-making empowerment in the region. The lowest modern contraceptive use (22.1%) was found in Afghanistan and the highest (53.2%) in Bangladesh. The multivariate results depict that the overall measure of women empowerment does not affect modern contraceptive use among poor and rich women in most of South Asian countries. However, the decision-making empowerment plays a significant role among both poor and rich women to use modern contraceptive methods across South Asian countries. Conclusions: The effect of women’s empowerment on modern contraceptive use is not consistent across countries, and among poor and rich segment of population. Of the three dimensions of women’s empowerment, the autonomy of decision making in household affairs emerged as a stronger determinant of mCPR as compared with social independence and attitude towards violence against women.

Keywords: women empowerment, modern contraceptive use, South Asia, women autonomy

Procedia PDF Downloads 82
1574 Dynamic Reliability for a Complex System and Process: Application on Offshore Platform in Mozambique

Authors: Raed KOUTA, José-Alcebiades-Ernesto HLUNGUANE, Eric Châtele

Abstract:

The search for and exploitation of new fossil energy resources is taking place in the context of the gradual depletion of existing deposits. Despite the adoption of international targets to combat global warming, the demand for fuels continues to grow, contradicting the movement towards an energy-efficient society. The increase in the share of offshore in global hydrocarbon production tends to compensate for the depletion of terrestrial reserves, thus constituting a major challenge for the players in the sector. Through the economic potential it represents, and the energy independence it provides, offshore exploitation is also a challenge for States such as Mozambique, which have large maritime areas and whose environmental wealth must be considered. The exploitation of new reserves on economically viable terms depends on available technologies. The development of deep and ultra-deep offshore requires significant research and development efforts. Progress has also been made in managing the multiple risks inherent in this activity. Our study proposes a reliability approach to develop products and processes designed to live at sea. Indeed, the context of an offshore platform requires highly reliable solutions to overcome the difficulties of access to the system for regular maintenance and quick repairs and which must resist deterioration and degradation processes. One of the characteristics of failures that we consider is the actual conditions of use that are considered 'extreme.' These conditions depend on time and the interactions between the different causes. These are the two factors that give the degradation process its dynamic character, hence the need to develop dynamic reliability models. Our work highlights mathematical models that can explicitly manage interactions between components and process variables. These models are accompanied by numerical resolution methods that help to structure a dynamic reliability approach in a physical and probabilistic context. The application developed makes it possible to evaluate the reliability, availability, and maintainability of a floating storage and unloading platform for liquefied natural gas production.

Keywords: dynamic reliability, offshore plateform, stochastic process, uncertainties

Procedia PDF Downloads 119
1573 Beneficial Effect of Micropropagation Coupled with Mycorrhization on Enhancement of Growth Performance of Medicinal Plants

Authors: D. H. Tejavathi

Abstract:

Medicinal plants are globally valuable sources of herbal products. Wild populations of many medicinal plants are facing threat of extinction because of their narrow distribution, endemicity, and degradation of specific habitats. Micropropagation is an established in vitro technique by which large number of clones can be obtained from a small bit of explants in a short span of time within a limited space. Mycorrhization can minimize the transient transplantation shock, experienced by the micropropagated plants when they are transferred from lab to land. AM fungal association improves the physiological status of the host plants through better uptake of water and nutrients, particularly phosphorus. Consequently, the growth performance and biosynthesis of active principles are significantly enhanced in AM fungal treated plants. Bacopa monnieri, Andrographis paniculata, Agave vera-curz, Drymaria cordata and Majorana hortensis, important medicinal plants used in various indigenous systems of medicines, are selected for the present study. They form the main constituents of many herbal formulations. Standard in vitro techniques were followed to obtain the micropropagated plants. Shoot tips and nodal segments were used as explants. Explants were cultured on Murashige and Skoog, and Phillips and Collins media supplemented with various combinations of growth regulators. Multiple shoots were obtained on a media containing both auxins and cytokinins at various concentrations and combinations. Multiple shoots were then transferred to rooting media containing auxins for root induction. Thus, obtained in vitro regenerated plants were subjected to brief acclimatization before transferring them to land. One-month-old in vitro plants were treated with AM fungi, and the symbiotic effect on the overall growth parameters was analyzed. It was found that micropropagation coupled with mycorrhization has significant effect on the enhancement of biomass and biosynthesis of active principles in these selected medicinal plants. In vitro techniques coupled with mycorrhization have opened a possibility of obtaining better clones in respect of enhancement of biomass and biosynthesis of active principles. Beneficial effects of AM fungal association with medicinal plants are discussed.

Keywords: cultivation, medicinal plants, micropropagation, mycorrhization

Procedia PDF Downloads 170
1572 Insulin-Producing Cells from Adult Human Bone Marrow Mesenchymal Stem Cells Control Chemically-Induced Diabetes in Dogs

Authors: Maha Azzam, Mahmoud Gabr, Mahmoud Zakaria, Ayman Refaie, Amani Ismail, Sherry Khater, Sylvia Ashamallah, Mohamed Ghoniem

Abstract:

Evidence was provided that human bone marrow-derived mesenhymal stem cells (HBM-MSCs) could be differentiated to form insulin-producing cells (IPCs). Transplantation of these cells was able to cure chemically-induced diabetes in nude mice. The efficacy of these cells to control diabetes in large animals was carried out to evaluate the sufficient number of cells needed/Kg body weight and to determine the functional longevity in vivo. Materials/Methods: Ten male mongrel dogs weighing 15-20 Kg were used in this study. Diabetes was chemically-induced in 7 dogs by a mixture of alloxan and streptozotocin. Three non-diabetic served as normal controls. Differentiated HBM-MSCs (5 million/Kg) were encapsulated in theracyte capsules and transplanted beneath the rectus sheath. Each dog received 2 capsules. One dog died 4 days postoperative from inhalation pneumonia. The remaining 6 dogs were followed up for 6-18 months. Results: Four dogs became normoglycemic within 6-8 weeks with normal glucose tolerance curves providing evidence that the transplanted cells were glucose-sensitive and insulin-responsive. In the remaining 2 dogs, fasting blood glucose was reduced but did not reach euglycemic levels. The sera of all transplanted dogs contained human insulin and c-peptide but negligible levels of canine insulin. When the HBM-MSCs loaded capsules were removed, rapid return of diabetic state was noted. The harvested capsules were examined by immunofluorescence. IPCs were seen and co-expression of with c-peptide was confirmed. Furthermore, all the pancreatic endocrine genes were expressed by the transplanted cells. Conclusions: This study provided evidence that theracyte capsules could protect the xenogenic HBM-MSCs from the host immune response. This is an important issue when clinical stem cell therapy is considered for definitive treatment for T1DM.

Keywords: diabetes, mesenchymal stem cells, dogs, Insulin-producing cells

Procedia PDF Downloads 203
1571 Peach as a Potential Functional Food: Biological Activity and Important Phenolic Compound Source

Authors: Luís R. Silva, Catarina Bento, Ana C. Gonçalves, Fábio Jesus, Branca M. Silva

Abstract:

Nowadays, the general population is more and more concerned about nutrition and the health implications of an unbalanced diet. Current knowledge regarding the health benefits and antioxidant properties of certain foods such as fruits and vegetables has gained the interest of both the general public and scientific community. Peach (Prunus persica (L.) Batsch) is one of the most consumed fruits worldwide, with low sugar contents and a broad range of nutrients essential to the normal functioning of the body. Six different peach cultivars from the Fundão region in Portugal were evaluated regarding their phenolic composition by LC-DAD and biological activity. The prepared extracts’ capacity to scavenge free-radicals was tested through the stable free radical DPPH• and nitric oxide (•NO). Additionally, antidiabetic potential and protective effects against peroxyl radical (ROO•) induced damage to erythrocytes were also tested. LC-DAD analysis allowed the identification of 17 phenolic compounds, among which 5-O-caffeoylquinic acids and 3-O-caffeoylquinic acids are pointed out as the most abundant. Regarding the antioxidant activity, all cultivars displayed concentration-dependent free-radical scavenging activity against both nitrogen species and DPPH•. In respect to α-glucosidase inhibitory activity, Royal Magister and Royal Glory presented the highest inhibitory activity (IC50 = 11.7 ± 1.4 and 17.1 ± 1.7 μg/mL, respectively), nevertheless all six cultivars presented higher activity than the control acarbose. As for the protective effect of Royal Lu extract on the oxidative damage induced in erythrocytes by ROO•, the results were quite promising showing inhibition IC50 values of 110.0 ± 4.5 μg/mL and 83.8 ± 6.5 μg/mL for hemolysis and hemoglobin oxidation, respectively. The demonstrated activity is of course associated to the peaches’ phenolic profile, rich in phenolic acids and flavonoids with high hydrogen donating capacity. These compounds have great industrial interest for the manufacturing of natural products. The following step would naturally be the extraction and isolation from the plant tissues and large-scale production through biotechnology techniques.

Keywords: antioxidants, functional food, phenolic compounds, peach

Procedia PDF Downloads 293
1570 Vertical and Horizantal Distribution Patterns of Major and Trace Elements: Surface and Subsurface Sediments of Endhorheic Lake Acigol Basin, Denizli Turkey

Authors: M. Budakoglu, M. Karaman

Abstract:

Lake Acıgöl is located in area with limited influences from urban and industrial pollution sources, there is nevertheless a need to understand all potential lithological and anthropogenic sources of priority contaminants in this closed basin. This study discusses vertical and horizontal distribution pattern of major, trace elements of recent lake sediments to better understand their current geochemical analog with lithological units in the Lake Acıgöl basin. This study also provides reliable background levels for the region by the detailed surfaced lithological units data. The detail results of surface, subsurface and shallow core sediments from these relatively unperturbed ecosystems, highlight its importance as conservation area, despite the high-scale industrial salt production activity. While P2O5/TiO2 versus MgO/CaO classification diagram indicate magmatic and sedimentary origin of lake sediment, Log(SiO2/Al2O3) versus Log(Na2O/K2O) classification diagrams express lithological assemblages of shale, iron-shale, vacke and arkose. The plot between TiO2 vs. SiO2 and P2O5/TiO2 vs. MgO/CaO also supports the origin of the primary magma source. The average compositions of the 20 different lithological units used as a proxy for geochemical background in the study area. As expected from weathered rock materials, there is a large variation in the major element content for all analyzed lake samples. The A-CN-K and A-CNK-FM ternary diagrams were used to deduce weathering trends. Surface and subsurface sediments display an intense weathering history according to these ternary diagrams. The most of the sediments samples plot around UCC and TTG, suggesting a low to moderate weathering history for the provenance. The sediments plot in a region clearly suggesting relative similar contents in Al2O3, CaO, Na2O, and K2O from those of lithological samples.

Keywords: Lake Acıgöl, recent lake sediment, geochemical speciation of major and trace elements, heavy metals, Denizli, Turkey

Procedia PDF Downloads 410
1569 Physiological and Psychological Influence on Office Workers during Demand Response

Authors: Megumi Nishida, Naoya Motegi, Takurou Kikuchi, Tomoko Tokumura

Abstract:

In recent years, power system has been changed and flexible power pricing system such as demand response has been sought in Japan. The demand response system is simple in the household sector and the owner, decision-maker, can gain the benefits of power saving. On the other hand, the execution of the demand response in the office building is more complex than household because various people such as owners, building administrators and occupants are involved in making decisions. While the owners benefit from the demand saving, the occupants are forced to be exposed to demand-saved environment certain benefits. One of the reasons is that building systems are usually centralized control and each occupant cannot choose either participate demand response event or not, and contribution of each occupant to demand response is unclear to provide incentives. However, the recent development of IT and building systems enables the personalized control of office environment where each occupant can control the lighting level or temperature around him or herself. Therefore, it can be possible to have a system which each occupant can make a decision of demand response participation in office building. This study investigates the personal behavior upon demand response requests, under the condition where each occupant can adjust their brightness individually in their workspace. Once workers participate in the demand response, their task lights are automatically turned off. The participation rates in the demand response events are compared between four groups which are divided by different motivation, the presence or absence of incentives and the way of participation. The result shows that there are the significant differences of participation rates in demand response event between four groups. The way of participation has a large effect on the participation rate. ‘Opt-out’ group, where the occupants are automatically enrolled in a demand response event if they don't express non-participation, will have the highest participation rate in the four groups. The incentive has also an effect on the participation rate. This study also reports that the impact of low illumination office environment on the occupants, such as stress or fatigue. The electrocardiogram and the questionnaire are used to investigate the autonomic nervous activity and subjective symptoms about the fatigue of the occupants. There is no big difference between dim workspace during demand response event and bright workspace in autonomic nervous activity and fatigue.

Keywords: demand response, illumination, questionnaire, electrocardiogram

Procedia PDF Downloads 350
1568 Understanding the Top Questions Asked about Hong Kong by Travellers Worldwide through a Corpus-Based Discourse Analytic Approach

Authors: Phoenix W. Y. Lam

Abstract:

As one of the most important service-oriented industries in contemporary society, tourism has increasingly seen the influence of the Internet on all aspects of travelling. Travellers nowadays habitually research online before making travel-related decisions. One platform on which such research is conducted is destination forums. The emergence of such online destination forums in the last decade has allowed tourists to share their travel experiences quickly and easily with a large number of online users around the world. As such, these destination forums also provide invaluable data for tourism bodies to better understand travellers’ views on their destinations. Collecting posts from the Hong Kong travel forum on the world’s largest travel website TripAdvisor®, the present study identifies the top questions asked by TripAdvisor users about Hong Kong through a corpus-based discourse analytic approach. Based on questions posted on the forum and their associated meta-data gathered in a one-year period, the study examines the top questions asked by travellers around the world to identify the key geographical locations in which users have shown the greatest interest in the city. Questions raised by travellers from different geographical locations are also compared to see if traveller communities by location vary in terms of their areas of interest. This analysis involves the study of key words and concordance of frequently-occurring items and a close reading of representative examples in context. Findings from the present study show that travellers who asked the most questions about Hong Kong are from North America and Asia, and that travellers from different locations have different concerns and interests, which are clearly reflected in the language of the questions asked on the travel forum. These findings can therefore provide tourism organisations with useful information about the key markets that should be targeted for promotional purposes, and can also allow such organisations to design advertising campaigns which better address the specific needs of such markets. The present study thus demonstrates the value of applying linguistic knowledge and methodologies to the domain of tourism to address practical issues.

Keywords: corpus, hong kong, online travel forum, tourism, TripAdvisor

Procedia PDF Downloads 176