Search results for: real time kinematics
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 20507

Search results for: real time kinematics

11927 Structural and Functional Correlates of Reaction Time Variability in a Large Sample of Healthy Adolescents and Adolescents with ADHD Symptoms

Authors: Laura O’Halloran, Zhipeng Cao, Clare M. Kelly, Hugh Garavan, Robert Whelan

Abstract:

Reaction time (RT) variability on cognitive tasks provides the index of the efficiency of executive control processes (e.g. attention and inhibitory control) and is considered to be a hallmark of clinical disorders, such as attention-deficit disorder (ADHD). Increased RT variability is associated with structural and functional brain differences in children and adults with various clinical disorders, as well as poorer task performance accuracy. Furthermore, the strength of functional connectivity across various brain networks, such as the negative relationship between the task-negative default mode network and task-positive attentional networks, has been found to reflect differences in RT variability. Although RT variability may provide an index of attentional efficiency, as well as being a useful indicator of neurological impairment, the brain substrates associated with RT variability remain relatively poorly defined, particularly in a healthy sample. Method: Firstly, we used the intra-individual coefficient of variation (ICV) as an index of RT variability from “Go” responses on the Stop Signal Task. We then examined the functional and structural neural correlates of ICV in a large sample of 14-year old healthy adolescents (n=1719). Of these, a subset had elevated symptoms of ADHD (n=80) and was compared to a matched non-symptomatic control group (n=80). The relationship between brain activity during successful and unsuccessful inhibitions and gray matter volume were compared with the ICV. A mediation analysis was conducted to examine if specific brain regions mediated the relationship between ADHD symptoms and ICV. Lastly, we looked at functional connectivity across various brain networks and quantified both positive and negative correlations during “Go” responses on the Stop Signal Task. Results: The brain data revealed that higher ICV was associated with increased structural and functional brain activation in the precentral gyrus in the whole sample and in adolescents with ADHD symptoms. Lower ICV was associated with lower activation in the anterior cingulate cortex (ACC) and medial frontal gyrus in the whole sample and in the control group. Furthermore, our results indicated that activation in the precentral gyrus (Broadman Area 4) mediated the relationship between ADHD symptoms and behavioural ICV. Conclusion: This is the first study first to investigate the functional and structural correlates of ICV collectively in a large adolescent sample. Our findings demonstrate a concurrent increase in brain structure and function within task-active prefrontal networks as a function of increased RT variability. Furthermore, structural and functional brain activation patterns in the ACC, and medial frontal gyrus plays a role-optimizing top-down control in order to maintain task performance. Our results also evidenced clear differences in brain morphometry between adolescents with symptoms of ADHD but without clinical diagnosis and typically developing controls. Our findings shed light on specific functional and structural brain regions that are implicated in ICV and yield insights into effective cognitive control in healthy individuals and in clinical groups.

Keywords: ADHD, fMRI, reaction-time variability, default mode, functional connectivity

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11926 Development of Ketorolac Tromethamine Encapsulated Stealth Liposomes: Pharmacokinetics and Bio Distribution

Authors: Yasmin Begum Mohammed

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Ketorolac tromethamine (KTM) is a non-steroidal anti-inflammatory drug with a potent analgesic and anti-inflammatory activity due to prostaglandin related inhibitory effect of drug. It is a non-selective cyclo-oxygenase inhibitor. The drug is currently used orally and intramuscularly in multiple divided doses, clinically for the management arthritis, cancer pain, post-surgical pain, and in the treatment of migraine pain. KTM has short biological half-life of 4 to 6 hours, which necessitates frequent dosing to retain the action. The frequent occurrence of gastrointestinal bleeding, perforation, peptic ulceration, and renal failure lead to the development of other drug delivery strategies for the appropriate delivery of KTM. The ideal solution would be to target the drug only to the cells or tissues affected by the disease. Drug targeting could be achieved effectively by liposomes that are biocompatible and biodegradable. The aim of the study was to develop a parenteral liposome formulation of KTM with improved efficacy while reducing side effects by targeting the inflammation due to arthritis. PEG-anchored (stealth) and non-PEG-anchored liposomes were prepared by thin film hydration technique followed by extrusion cycle and characterized for in vitro and in vivo. Stealth liposomes (SLs) exhibited increase in percent encapsulation efficiency (94%) and 52% percent of drug retention during release studies in 24 h with good stability for a period of 1 month at -20°C and 4°C. SLs showed about maximum 55% of edema inhibition with significant analgesic effect. SLs produced marked differences over those of non-SL formulations with an increase in area under plasma concentration time curve, t₁/₂, mean residence time, and reduced clearance. 0.3% of the drug was detected in arthritic induced paw with significantly reduced drug localization in liver, spleen, and kidney for SLs when compared to other conventional liposomes. Thus SLs help to increase the therapeutic efficacy of KTM by increasing the targeting potential at the inflammatory region.

Keywords: biodistribution, ketorolac tromethamine, stealth liposomes, thin film hydration technique

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11925 Numerical Study of a Ventilation Principle Based on Flow Pulsations

Authors: Amir Sattari, Mac Panah, Naeim Rashidfarokhi

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To enhance the mixing of fluid in a rectangular enclosure with a circular inlet and outlet, an energy-efficient approach is further investigated through computational fluid dynamics (CFD). Particle image velocimetry (PIV) measurements help confirm that the pulsation of the inflow velocity improves the mixing performance inside the enclosure considerably without increasing energy consumption. In this study, multiple CFD simulations with different turbulent models were performed. The results obtained were compared with experimental PIV results. This study investigates small-scale representations of flow patterns in a ventilated rectangular room. The objective is to validate the concept of an energy-efficient ventilation strategy with improved thermal comfort and reduction of stagnant air inside the room. Experimental and simulated results confirm that through pulsation of the inflow velocity, strong secondary vortices are generated downstream of the entrance wall-jet. The pulsatile inflow profile promotes a periodic generation of vortices with stronger eddies despite a relatively low inlet velocity, which leads to a larger boundary layer with increased kinetic energy in the occupied zone. A real-scale study was not conducted; however, it can be concluded that a constant velocity inflow profile can be replaced with a lower pulsated flow rate profile while preserving the mixing efficiency. Among the turbulent CFD models demonstrated in this study, SST-kω is most advantageous, exhibiting a similar global airflow pattern as in the experiments. The detailed near-wall velocity profile is utilized to identify the wall-jet instabilities that consist of mixing and boundary layers. The SAS method was later applied to predict the turbulent parameters in the center of the domain. In both cases, the predictions are in good agreement with the measured results.

Keywords: CFD, PIV, pulsatile inflow, ventilation, wall-jet

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11924 Innovative Screening Tool Based on Physical Properties of Blood

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

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

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

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11923 Translation Directionality: An Eye Tracking Study

Authors: Elahe Kamari

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Research on translation process has been conducted for more than 20 years, investigating various issues and using different research methodologies. Most recently, researchers have started to use eye tracking to study translation processes. They believed that the observable, measurable data that can be gained from eye tracking are indicators of unobservable cognitive processes happening in the translators’ mind during translation tasks. The aim of this study was to investigate directionality in translation processes through using eye tracking. The following hypotheses were tested: 1) processing the target text requires more cognitive effort than processing the source text, in both directions of translation; 2) L2 translation tasks on the whole require more cognitive effort than L1 tasks; 3) cognitive resources allocated to the processing of the source text is higher in L1 translation than in L2 translation; 4) cognitive resources allocated to the processing of the target text is higher in L2 translation than in L1 translation; and 5) in both directions non-professional translators invest more cognitive effort in translation tasks than do professional translators. The performance of a group of 30 male professional translators was compared with that of a group of 30 male non-professional translators. All the participants translated two comparable texts one into their L1 (Persian) and the other into their L2 (English). The eye tracker measured gaze time, average fixation duration, total task length and pupil dilation. These variables are assumed to measure the cognitive effort allocated to the translation task. The data derived from eye tracking only confirmed the first hypothesis. This hypothesis was confirmed by all the relevant indicators: gaze time, average fixation duration and pupil dilation. The second hypothesis that L2 translation tasks requires allocation of more cognitive resources than L1 translation tasks has not been confirmed by all four indicators. The third hypothesis that source text processing requires more cognitive resources in L1 translation than in L2 translation and the fourth hypothesis that target text processing requires more cognitive effort in L2 translation than L1 translation were not confirmed. It seems that source text processing in L2 translation can be just as demanding as in L1 translation. The final hypothesis that non-professional translators allocate more cognitive resources for the same translation tasks than do the professionals was partially confirmed. One of the indicators, average fixation duration, indicated higher cognitive effort-related values for professionals.

Keywords: translation processes, eye tracking, cognitive resources, directionality

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11922 A Parallel Implementation of k-Means in MATLAB

Authors: Dimitris Varsamis, Christos Talagkozis, Alkiviadis Tsimpiris, Paris Mastorocostas

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The aim of this work is the parallel implementation of k-means in MATLAB, in order to reduce the execution time. Specifically, a new function in MATLAB for serial k-means algorithm is developed, which meets all the requirements for the conversion to a function in MATLAB with parallel computations. Additionally, two different variants for the definition of initial values are presented. In the sequel, the parallel approach is presented. Finally, the performance tests for the computation times respect to the numbers of features and classes are illustrated.

Keywords: K-means algorithm, clustering, parallel computations, Matlab

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11921 Alternative Energy and Carbon Source for Biosurfactant Production

Authors: Akram Abi, Mohammad Hossein Sarrafzadeh

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Because of their several advantages over chemical surfactants, biosurfactants have given rise to a growing interest in the past decades. Advantages such as lower toxicity, higher biodegradability, higher selectivity and applicable at extreme temperature and pH which enables them to be used in a variety of applications such as: enhanced oil recovery, environmental and pharmaceutical applications, etc. Bacillus subtilis produces a cyclic lipopeptide, called surfactin, which is one of the most powerful biosurfactants with ability to decrease surface tension of water from 72 mN/m to 27 mN/m. In addition to its biosurfactant character, surfactin exhibits interesting biological activities such as: inhibition of fibrin clot formation, lyses of erythrocytes and several bacterial spheroplasts, antiviral, anti-tumoral and antibacterial properties. Surfactin is an antibiotic substance and has been shown recently to possess anti-HIV activity. However, application of biosurfactants is limited by their high production cost. The cost can be reduced by optimizing biosurfactant production using cheap feed stock. Utilization of inexpensive substrates and unconventional carbon sources like urban or agro-industrial wastes is a promising strategy to decrease the production cost of biosurfactants. With suitable engineering optimization and microbiological modifications, these wastes can be used as substrates for large-scale production of biosurfactants. As an effort to fulfill this purpose, in this work we have tried to utilize olive oil as second carbon source and also yeast extract as second nitrogen source to investigate the effect on both biomass and biosurfactant production improvement in Bacillus subtilis cultures. Since the turbidity of the culture was affected by presence of the oil, optical density was compromised and no longer could be used as an index of growth and biomass concentration. Therefore, cell Dry Weight measurements with applying necessary tactics for removing oil drops to prevent interference with biomass weight were carried out to monitor biomass concentration during the growth of the bacterium. The surface tension and critical micelle dilutions (CMD-1, CMD-2) were considered as an indirect measurement of biosurfactant production. Distinctive and promising results were obtained in the cultures containing olive oil compared to cultures without it: more than two fold increase in biomass production (from 2 g/l to 5 g/l) and considerable reduction in surface tension, down to 40 mN/m at surprisingly early hours of culture time (only 5hr after inoculation). This early onset of biosurfactant production in this culture is specially interesting when compared to the conventional cultures at which this reduction in surface tension is not obtained until 30 hour of culture time. Reducing the production time is a very prominent result to be considered for large scale process development. Furthermore, these results can be used to develop strategies for utilization of agro-industrial wastes (such as olive oil mill residue, molasses, etc.) as cheap and easily accessible feed stocks to decrease the high costs of biosurfactant production.

Keywords: agro-industrial waste, bacillus subtilis, biosurfactant, fermentation, second carbon and nitrogen source, surfactin

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11920 Short-Term Association of In-vehicle Ultrafine Particles and Black Carbon Concentrations with Respiratory Health in Parisian Taxi Drivers

Authors: Melissa Hachem, Maxime Loizeau, Nadine Saleh, Isabelle Momas, Lynda Bensefa-Colas

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Professional drivers are exposed inside their vehicles to high levels of air pollutants due to the considerable time they spend close to motor vehicle emissions. Little is known about ultrafine particles (UFP) or black carbon (BC) adverse respiratory health effects compared to the regulated pollutants. We aimed to study the short-term associations between UFP and BC concentrations inside vehicles and (1) the onset of mucosal irritation and (2) the acute changes in lung function of Parisian taxi drivers during a working day. An epidemiological study was carried out on 50 taxi drivers in Paris. UFP and BC were measured inside their vehicles with DiSCmini® and microAeth®, respectively. On the same day, the frequency and the severity of nose, eye, and throat irritations were self-reported by each participant and a spirometry test was performed before and after the work shift. Multivariate analysis was used to evaluate the associations between in-taxis UFP and BC concentrations and mucosal irritation and lung function, after adjustment for potential confounders. In-taxis UFP concentrations ranged from 17.9 to 37.9 × 103 particles/cm³ and BC concentrations from 2.2 to 3.9 μg/m³, during a mean of 9 ± 2 working hours. Significant dose-response relationships were observed between in-taxis UFP concentrations and both nasal irritation and lung function. The increase of in-taxis UFP (for an interquartile range of 20 × 103 particles/cm3) was associated to an increase in nasal irritation (adjusted OR = 6.27 [95% CI: 1.02 to 38.62]) and to a reduction in forced expiratory flow at 25–75% by −7.44% [95% CI: −12.63 to −2.24], forced expiratory volume in one second by −4.46% [95% CI: −6.99 to −1.93] and forced vital capacity by −3.31% [95% CI: −5.82 to −0.80]. Such associations were not found with BC. Incident throat and eye irritations were not related to in-vehicle particles exposure; however, they were associated with outdoor air quality (estimated by the Atmo index) and in-vehicle humidity, respectively. This study is the first to show a significant association, within a short-period of time, between in-vehicle UFP exposure and acute respiratory effects in professional drivers.

Keywords: black carbon, lung function, mucosal irritation, taxi drivers, ultrafine particles

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11919 Trends, Status, and Future Directions of Artificial Intelligence in Human Resources Disciplines: A Bibliometric Analysis

Authors: Gertrude I. Hewapathirana, Loi A. Nguyen, Mohammed M. Mostafa

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Artificial intelligence (AI) technologies and tools are swiftly integrating into many functions of all organizations as a competitive drive to enhance innovations, productivity, efficiency, faster and precise decision making to keep up with rapid changes in the global business arena. Despite increasing research on AI technologies in production, manufacturing, and information management, AI in human resource disciplines is still lagging. Though a few research studies on HR informatics, recruitment, and HRM in general, how to integrate AI in other HR functional disciplines (e.g., compensation, training, mentoring and coaching, employee motivation) is rarely researched. Many inconsistencies of research hinder developing up-to-date knowledge on AI in HR disciplines. Therefore, exploring eight research questions, using bibliometric network analysis combined with a meta-analysis of published research literature. The authors attempt to generate knowledge on the role of AI in improving the efficiency of HR functional disciplines. To advance the knowledge for the benefit of researchers, academics, policymakers, and practitioners, the study highlights the types of AI innovations and outcomes, trends, gaps, themes and topics, fast-moving disciplines, key players, and future directions.AI in HR informatics in high tech firms is the dominant theme in many research publications. While there is increasing attention from researchers and practitioners, there are many gaps between the promise, potential, and real AI applications in HR disciplines. A higher knowledge gap raised many unanswered questions regarding legal, ethical, and morale aspects of AI in HR disciplines as well as the potential contributions of AI in HR disciplines that may guide future research directions. Though the study provides the most current knowledge, it is limited to peer-reviewed empirical, theoretical, and conceptual research publications stored in the WoS database. The implications for theory, practice, and future research are discussed.

Keywords: artificial intelligence, human resources, bibliometric analysis, research directions

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11918 Identifying and Quantifying Factors Affecting Traffic Crash Severity under Heterogeneous Traffic Flow

Authors: Praveen Vayalamkuzhi, Veeraragavan Amirthalingam

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Studies on safety on highways are becoming the need of the hour as over 400 lives are lost every day in India due to road crashes. In order to evaluate the factors that lead to different levels of crash severity, it is necessary to investigate the level of safety of highways and their relation to crashes. In the present study, an attempt is made to identify the factors that contribute to road crashes and to quantify their effect on the severity of road crashes. The study was carried out on a four-lane divided rural highway in India. The variables considered in the analysis includes components of horizontal alignment of highway, viz., straight or curve section; time of day, driveway density, presence of median; median opening; gradient; operating speed; and annual average daily traffic. These variables were considered after a preliminary analysis. The major complexities in the study are the heterogeneous traffic and the speed variation between different classes of vehicles along the highway. To quantify the impact of each of these factors, statistical analyses were carried out using Logit model and also negative binomial regression. The output from the statistical models proved that the variables viz., horizontal components of the highway alignment; driveway density; time of day; operating speed as well as annual average daily traffic show significant relation with the severity of crashes viz., fatal as well as injury crashes. Further, the annual average daily traffic has significant effect on the severity compared to other variables. The contribution of highway horizontal components on crash severity is also significant. Logit models can predict crashes better than the negative binomial regression models. The results of the study will help the transport planners to look into these aspects at the planning stage itself in the case of highways operated under heterogeneous traffic flow condition.

Keywords: geometric design, heterogeneous traffic, road crash, statistical analysis, level of safety

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11917 The Successful in Construction Project via Effectiveness of Project Team

Authors: Zarabizan Zakaria, Hayati Zainal

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The construction industry is one of the most important sectors that contribute to the nation’s economy and catalyze towards the growth of other industries. However, some construction projects have not been completed on its stipulated time and duration, scope and budget due to several factors. This problem arises due to the weaknesses of human factors, especially from ineffective leadership quality practiced by project managers and contractors in managing project teams. Therefore, a construction project should impose the element of Project Team. The project team is formed in the implementation of the project which includes the project brief, project scope, customer requirements and provided designs. Many organizations in the construction sector use teams to meet today's global competition and customer expectations, however, team effectiveness evaluation is required. In insuring the construction team is successful and effectiveness, the construction department must encourage, measure, set up, and evaluate or review the effectiveness of project team that was formed. In order to produce a better outcome for a high-end project, an effective and efficient project team is required which also help in increasing overall productivity. The purpose of this study is to determine the role of team effectiveness in the construction project team based on the overall construction project performance. It examines several different factors which related to team effectiveness. It also examines the relationship between team effectiveness factor and project performance aspect. Team Effect Review and Project Performance Review are developed to be used for data collection. Data collected were analyzed using several statistical tests. Results obtained from data analysis are validated using semi-structured interviews. Besides that, a comprehensive survey were developed to assess the way construction project teams in order to maintain its effectiveness throughout the project phase. In order to determine a project successful it has been found that Project Team Leadership is the most important factor. In addition, the definition of team effectiveness in the construction project team is developed based on the perspective of project clients and project team members. The results of this study are expected to provide an idea on the factors that are needed to be focused on improving the team's effectiveness towards project performance aspects. At the same time, the definition of team effectiveness from team members and owner views has been developed in order to provide a better understanding of the word team's effectiveness in construction projects.

Keywords: project team, leadership, construction project, project successful

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11916 Urban Sustainable Development with Flood Crisis Management Approach

Authors: Ali Liaghat, Navid Tavanpour, Nima Tavanpour

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An increase in population and prevalence of urbanity have led plan makers and decision makers put effort into sustainable development of cities at national and local levels. One of the important issues in urban development is compliance with safety issues in cities. Despite natural disasters and unexpected events such as floods, earthquakes, hurricanes, fires, etc., urban development should be regarded as an axiom, or else any form of construction and development is not safe, because it will greatly harm economic growth and development and pose an obstacle to achieving sustainable development, plus a loss to lives and finances of people. Therefore, in line with urban development, it is necessary to identify particular environmental and local issues as determinants and pay attention to them at the top of everything, in that we can call it a good action and factor in urban sustainable developments. Physical structure of each city represents how it has developed or its development shaped and what incidents, changes, natural disasters it has undergone over time. Since any form of development plan should be in accordance with the previous situations of cities, disregarding it, unfortunately, can escalate into uncontrolled urban development, non-resistant and unstable construction against earthquake or invasion of river areas, destruction of agricultural lands or vegetation, periodic floods over time. It has been viewed as serious threats to developing cities, and typically caused destruction of bed and other urban facilities as well as damages to lives and finances. In addition, uncontrolled development has caused cities to look ugly in terms of urban façade, and off and on such unplanned measures caused the country to face countless losses, and it not only vitiates expenses incurred, but it will also impose additional costs of reconstruction, i.e. it is unsustainable development. Thus, in this paper, in addition to a discussion about necessity for a profound attitude toward this subject and making long-term plans, programs for organizing river and its surrounding area, creating open and green urban spaces, retrofitting and flood preventing are presented for sustainable safety and development of cities along with a critique of successful countries.

Keywords: flood, sustainable development, urbanisation, urban management

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11915 Micro-Droplet Formation in a Microchannel under the Effect of an Electric Field: Experiment

Authors: Sercan Altundemir, Pinar Eribol, A. Kerem Uguz

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Microfluidics systems allow many-large scale laboratory applications to be miniaturized on a single device in order to reduce cost and advance fluid control. Moreover, such systems enable to generate and control droplets which have a significant role on improved analysis for many chemical and biological applications. For example, they can be employed as the model for cells in microfluidic systems. In this work, the interfacial instability of two immiscible Newtonian liquids flowing in a microchannel is investigated. When two immiscible liquids are in laminar regime, a flat interface is formed between them. If a direct current electric field is applied, the interface may deform, i.e. may become unstable and it may be ruptured and form micro-droplets. First, the effect of thickness ratio, total flow rate, viscosity ratio of the silicone oil and ethylene glycol liquid couple on the critical voltage at which the interface starts to destabilize is investigated. Then the droplet sizes are measured under the effect of these parameters at various voltages. Moreover, the effect of total flow rate on the time elapsed for the interface to be ruptured to form droplets by hitting the wall of the channel is analyzed. It is observed that an increase in the viscosity or the thickness ratio of the silicone oil to the ethylene glycol has a stabilizing effect, i.e. a higher voltage is needed while the total flow rate has no effect on it. However, it is observed that an increase in the total flow rate results in shortening of the elapsed time for the interface to hit the wall. Moreover, the droplet size decreases down to 0.1 μL with an increase in the applied voltage, the viscosity ratio or the total flow rate or a decrease in the thickness ratio. In addition to these observations, two empirical models for determining the critical electric number, i.e., the dimensionless voltage and the droplet size and another model which is a combination of both models, for determining the droplet size at the critical voltage are established.

Keywords: droplet formation, electrohydrodynamics, microfluidics, two-phase flow

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11914 Simulation Based Analysis of Gear Dynamic Behavior in Presence of Multiple Cracks

Authors: Ahmed Saeed, Sadok Sassi, Mohammad Roshun

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Gears are important components with a vital role in many rotating machines. One of the common gear failure causes is tooth fatigue crack; however, its early detection is still a challenging task. The objective of this study is to develop a numerical model that simulates the effect of teeth cracks on the resulting gears vibrations and permits consequently to perform an early fault detection. In contrast to other published papers, this work incorporates the possibility of multiple simultaneous cracks with different depths. As cracks alter significantly the stiffness of the tooth, finite element software is used to determine the stiffness variation with respect to the angular position, for different combinations of crack orientation and depth. A simplified six degrees of freedom nonlinear lumped parameter model of a one-stage spur gear system is proposed to study the vibration with and without cracks. The model developed for calculating the stiffness with the crack permitted to update the physical parameters of the second-degree-of-freedom equations of motions describing the vibration of the gearbox. The vibration simulation results of the gearbox were by obtained using Simulink/Matlab. The effect of one crack with different levels was studied thoroughly. The change in the mesh stiffness and the vibration response were found to be consistent with previously published works. In addition, various statistical time domain parameters were considered. They showed different degrees of sensitivity toward the crack depth. Multiple cracks were also introduced at different locations and the vibration response along with the statistical parameters were obtained again for a general case of degradation (increase in crack depth, crack number and crack locations). It was found that although some parameters increase in value as the deterioration level increases, they show almost no change or even decrease when the number of cracks increases. Therefore, the use of any statistical parameters could be misleading if not considered in an appropriate way.

Keywords: Spur gear, cracked tooth, numerical simulation, time-domain parameters

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11913 Poverty and Illiteracy as a Key Factor for Crime and Unrest in Nigeria

Authors: Lawrence Emah

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Nigeria, Africa’s most populous nation is undoubtedly, currently going through one of the most difficult phases in her 55 years of existence as an independent nation. At no other time in her history is she under so much pressure of social unrest and unacceptable rate of crime and criminality than it is today. From the North where there is an insurgency to contend with, then to the South where kidnapping and armed robbery hold sway. These issues did not just sprout from nowhere; they have a root somewhere. This is why this paper seeks to bring to the fore poverty and illiteracy as leading causes of these twin social ills– crime and social restiveness as well as suggest practical solutions to the problems.

Keywords: crime, illiteracy, poverty, unrest

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11912 Pet Care Monitoring with Arduino

Authors: Sathapath Kilaso

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Nowadays people who live in the city tend to have a pet in order to relief the loneliness more than usual. It can be observed by the growth of the local pet industry. But the essentials of lifestyle of the urban people which is restricted by time and work might not allow the owner to take care of the pet properly. So this article will be about how to develop the prototype of pet care monitoring with Arduino Microcontroller. This prototype can be used to monitor the pet and its environment around the pet such as temperature (both pet’s temperature and outside temperature), humidity, food’s quantity, air’s quality and also be able to reduce the stress of the pet. This prototype can report the result back to the owner via online-channel such as website etc.

Keywords: pet care, Arduino Microcontroller, monitoring, prototype

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11911 Searching for the ‘Why’ of Gendered News: Journalism Practices and Societal Contexts

Authors: R. Simões, M. Silveirinha

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Driven by the need to understand the results of previous research that clearly shows deep unbalances of the media discourses about women and men in spite of the growing numbers of female journalists, our paper aims to progress from the 'what' to the 'why' of these unbalanced representations. Furthermore, it does so at a time when journalism is undergoing a dramatic change in terms of professional practices and in how media organizations are organized and run, affecting women in particular. While some feminist research points to the fact that female and male journalists evaluate the role of the news and production methods in similar ways feminist theorizing also suggests that thought and knowledge are highly influenced by social identity, which is also inherently affected by the experiences of gender. This is particularly important at a time of deep societal and professional changes. While there are persuasive discussions of gender identities at work in newsrooms in various countries studies on the issue will benefit from cases that focus on the particularities of local contexts. In our paper, we present one such case: the case of Portugal, a country hit hard by austerity measures that have affected all cultural industries including journalism organizations, already feeling the broader impacts of the larger societal changes of the media landscape. Can we gender these changes? How are they felt and understood by female and male journalists? And how are these discourses framed by androcentric, feminist and post-feminist sensibilities? Foregrounding questions of gender, our paper seeks to explore some of the interactions of societal and professional forces, identifying their gendered character and outlining how they shape journalism work in general and the production of unbalanced gender representations in particular. We do so grounded in feminist studies of journalism as well as feminist organizational and work studies, looking at a corpus of 20 in-depth interviews of female and male Portuguese journalists. The research findings illustrate how gender in journalism practices interacts with broader experiences of the cultural and economic contexts and show the ambivalences of these interactions in news organizations.

Keywords: gender, journalism, newsroom culture, Portuguese journalists

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11910 Exploring the Prebiotic Potential of Glucosamine

Authors: Shilpi Malik, Ramneek Kaur, Archita Gupta, Deepshikha Yadav, Ashwani Mathur, Manisha Singh

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Glucosamine (GS) is the most abundant naturally occurring amino monosaccharide and is normally produced in human body via cellular glucose metabolism. It is regarded as the building block of cartilage matrix and is also an essential component of cartilage matrix repair mechanism. Besides that, it can also be explored for its prebiotic potential as many bacterial species are known to utilize the amino sugar by acquiring them to form peptidoglycans and lipopolysaccharides in the bacterial cell wall. Glucosamine can therefore be considered for its fermentation by bacterial species present in the gut. Current study is focused on exploring the potential of glucosamine as prebiotic. The studies were done to optimize considerable concentration of GS to reach GI tract and being fermented by the complex gut microbiota and food grade GS was added to various Simulated Fluids of Gastro-Intestinal Tract (GIT) such as Simulated Saliva, Gastric Fluid (Fast and Fed State), Colonic fluid, etc. to detect its degradation. Since it was showing increase in microbial growth (CFU) with time, GS was Further, encapsulated to increase its residential time in the gut, which exhibited improved resistance to the simulated Gut conditions. Moreover, prepared microspehres were optimized and characterized for their encapsulation efficiency and toxicity. To further substantiate the prebiotic activity of Glucosamine, studies were also performed to determine the effect of Glucosamine on the known probiotic bacterial species, i.e. Lactobacillus delbrueckii (MTCC 911) and Bifidobacteriumbifidum (MTCC 5398). Culture conditions for glucosamine will be added in MRS media in anaerobic tube at 0.20%, 0.40%, 0.60%, 0.80%, and 1.0%, respectively. MRS media without GS was included in this experiment as the control. All samples were autoclaved at 118° C for 15 min. Active culture was added at 5% (v/v) to each anaerobic tube after cooling to room temperature and incubated at 37° C then determined biomass and pH and viable count at incubation 18h. The experiment was completed in triplicate and the results were presented as Mean ± SE (Standard error).The experimental results are conclusive and suggest Glucosamine to hold prebiotic properties.

Keywords: gastro intestinal tract, microspheres, peptidoglycans, simulated fluid

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11909 Improved Soil and Snow Treatment with the Rapid Update Cycle Land-Surface Model for Regional and Global Weather Predictions

Authors: Tatiana G. Smirnova, Stan G. Benjamin

Abstract:

Rapid Update Cycle (RUC) land surface model (LSM) was a land-surface component in several generations of operational weather prediction models at the National Center for Environment Prediction (NCEP) at the National Oceanic and Atmospheric Administration (NOAA). It was designed for short-range weather predictions with an emphasis on severe weather and originally was intentionally simple to avoid uncertainties from poorly known parameters. Nevertheless, the RUC LSM, when coupled with the hourly-assimilating atmospheric model, can produce a realistic evolution of time-varying soil moisture and temperature, as well as the evolution of snow cover on the ground surface. This result is possible only if the soil/vegetation/snow component of the coupled weather prediction model has sufficient skill to avoid long-term drift. RUC LSM was first implemented in the operational NCEP Rapid Update Cycle (RUC) weather model in 1998 and later in the Weather Research Forecasting Model (WRF)-based Rapid Refresh (RAP) and High-resolution Rapid Refresh (HRRR). Being available to the international WRF community, it was implemented in operational weather models in Austria, New Zealand, and Switzerland. Based on the feedback from the US weather service offices and the international WRF community and also based on our own validation, RUC LSM has matured over the years. Also, a sea-ice module was added to RUC LSM for surface predictions over the Arctic sea-ice. Other modifications include refinements to the snow model and a more accurate specification of albedo, roughness length, and other surface properties. At present, RUC LSM is being tested in the regional application of the Unified Forecast System (UFS). The next generation UFS-based regional Rapid Refresh FV3 Standalone (RRFS) model will replace operational RAP and HRRR at NCEP. Over time, RUC LSM participated in several international model intercomparison projects to verify its skill using observed atmospheric forcing. The ESM-SnowMIP was the last of these experiments focused on the verification of snow models for open and forested regions. The simulations were performed for ten sites located in different climatic zones of the world forced with observed atmospheric conditions. While most of the 26 participating models have more sophisticated snow parameterizations than in RUC, RUC LSM got a high ranking in simulations of both snow water equivalent and surface temperature. However, ESM-SnowMIP experiment also revealed some issues in the RUC snow model, which will be addressed in this paper. One of them is the treatment of grid cells partially covered with snow. RUC snow module computes energy and moisture budgets of snow-covered and snow-free areas separately by aggregating the solutions at the end of each time step. Such treatment elevates the importance of computing in the model snow cover fraction. Improvements to the original simplistic threshold-based approach have been implemented and tested both offline and in the coupled weather model. The detailed description of changes to the snow cover fraction and other modifications to RUC soil and snow parameterizations will be described in this paper.

Keywords: land-surface models, weather prediction, hydrology, boundary-layer processes

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11908 Association between Physical Inactivity and Sedentary Behaviours with Risk of Hypertension among Sedentary Occupation Workers: A Cross-Sectional Study

Authors: Hanan Badr, Fahad Manee, Rao Shashidhar, Omar Bayoumy

Abstract:

Introduction: Hypertension is the major risk factor for cardiovascular diseases and stroke and a universe leading cause of disability-adjusted life years and mortality. Adopting an unhealthy lifestyle is thought to be associated with developing hypertension regardless of predisposing genetic factors. This study aimed to examine the association between recreational physical activity (RPA), and sedentary behaviors with a risk of hypertension among ministry employees, where there is no role for occupational physical activity (PA), and to scrutinize participants’ time spent in RPA and sedentary behaviors on the working and weekend days. Methods: A cross-sectional study was conducted among randomly selected 2562 employees working at ten randomly selected ministries in Kuwait. To have a representative sample, the proportional allocation technique was used to define the number of participants in each ministry. A self-administered questionnaire was used to collect data about participants' socio-demographic characteristics, health status, and their 24 hours’ time use during a regular working day and a weekend day. The time use covered a list of 20 different activities practiced by a person daily. The New Zealand Physical Activity Questionnaire-Short Form (NZPAQ-SF) was used to assess the level of RPA. The scale generates three categories according to the number of hours spent in RPA/week: relatively inactive, relatively active, and highly active. Gender-matched trained nurses performed anthropometric measurements (weight and height) and measuring blood pressure (two readings) using an automatic blood pressure monitor (95% accuracy level compared to a calibrated mercury sphygmomanometer). Results: Participants’ mean age was 35.3±8.4 years, with almost equal gender distribution. About 13% of the participants were smokers, and 75% were overweight. Almost 10% reported doctor-diagnosed hypertension. Among those who did not, the mean systolic blood pressure was 119.9±14.2 and the mean diastolic blood pressure was 80.9±7.3. Moreover, 73.9% of participants were relatively physically inactive and 18% were highly active. Mean systolic and diastolic blood pressure showed a significant inverse association with the level of RPA (means of blood pressure measures were: 123.3/82.8 among relatively inactive, 119.7/80.4 among relatively active, and 116.6/79.6 among highly active). Furthermore, RPA occupied 1.6% and 1.8% of working and weekend days, respectively, while sedentary behaviors (watching TV, using electronics for social media or entertaining, etc.) occupied 11.2% and 13.1%, respectively. Sedentary behaviors were significantly associated with high levels of systolic and diastolic blood pressure. Binary logistic regression revealed that physical inactivity (OR=3.13, 95% CI: 2.25-4.35) and sedentary behaviors (OR=2.25, CI: 1.45-3.17) were independent risk factors for high systolic and diastolic blood pressure after adjustment for other covariates. Conclusions: Physical inactivity and sedentary lifestyle were associated with a high risk of hypertension. Further research to examine the independent role of RPA in improving blood pressure levels and cultural and occupational barriers for practicing RPA are recommended. Policies should be enacted in promoting PA in the workplace that might help in decreasing the risk of hypertension among sedentary occupation workers.

Keywords: physical activity, sedentary behaviors, hypertension, workplace

Procedia PDF Downloads 163
11907 Two-Protein Modified Gold Nanoparticles for Serological Diagnosis of Borreliosis

Authors: Mohammed Alasel, Michael Keusgen

Abstract:

Gold is a noble metal; in its nano-scale level (e.g. spherical nanoparticles), the conduction electrons are triggered to collectively oscillate with a resonant frequency when certain wavelengths of electromagnetic radiation interact with its surface; this phenomenon is known as surface plasmon resonance (SPR). SPR is responsible for giving the gold nanoparticles its intense red color depending mainly on its size, shape and distance between nanoparticles. A decreased distance between gold nanoparticles results in aggregation of them causing a change in color from red to blue. This aggregation enables gold nanoparticles to serve as a sensitive biosensoric indicator. In the proposed work, gold nanoparticles were modified with two proteins: i) Borrelia antigen, variable lipoprotein surface-exposed protein (VlsE), and ii) protein A. VlsE antigen induces a strong antibody response against Lyme disease and can be detected from early to late phase during the disease in humans infected with Borrelia. In addition, it shows low cross-reaction with the other non-pathogenic Borrelia strains. The high specificity of VlsE antigen to anti-Borrelia antibodies, combined simultaneously with the high specificity of protein A to the Fc region of all IgG human antibodies, was utilized to develop a rapid test for serological point of care diagnosis of borreliosis in human serum. Only in the presence of anti-Borrelia antibodies in the serum probe, an aggregation of gold nanoparticles can be observed, which is visible by a concentration-dependent colour shift from red (low IgG) to blue (high IgG). Experiments showed it is clearly possible to distinguish between positive and negative sera samples using a simple suspension of the two-protein modified gold nanoparticles in a very short time (30 minutes). The proposed work showed the potential of using such modified gold nanoparticles generally for serological diagnosis. Improved specificity and reduced assay time can be archived in applying increased salt concentrations combined with decreased pH values (pH 5).

Keywords: gold nanoparticles, gold aggregation, serological diagnosis, protein A, lyme borreliosis

Procedia PDF Downloads 391
11906 Integration of Agile Philosophy and Scrum Framework to Missile System Design Processes

Authors: Misra Ayse Adsiz, Selim Selvi

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In today's world, technology is competing with time. In order to catch up with the world's companies and adapt quickly to the changes, it is necessary to speed up the processes and keep pace with the rate of change of the technology. The missile system design processes, which are handled with classical methods, keep behind in this race. Because customer requirements are not clear, and demands are changing again and again in the design process. Therefore, in the system design process, a methodology suitable for the missile system design dynamics has been investigated and the processes used for catching up the era are examined. When commonly used design processes are analyzed, it is seen that any one of them is dynamic enough for today’s conditions. So a hybrid design process is established. After a detailed review of the existing processes, it is decided to focus on the Scrum Framework and Agile Philosophy. Scrum is a process framework. It is focused on to develop software and handling change management with rapid methods. In addition, agile philosophy is intended to respond quickly to changes. In this study, it is aimed to integrate Scrum framework and agile philosophy, which are the most appropriate ways for rapid production and change adaptation, into the missile system design process. With this approach, it is aimed that the design team, involved in the system design processes, is in communication with the customer and provide an iterative approach in change management. These methods, which are currently being used in the software industry, have been integrated with the product design process. A team is created for system design process. The roles of Scrum Team are realized with including the customer. A scrum team consists of the product owner, development team and scrum master. Scrum events, which are short, purposeful and time-limited, are organized to serve for coordination rather than long meetings. Instead of the classic system design methods used in product development studies, a missile design is made with this blended method. With the help of this design approach, it is become easier to anticipate changing customer demands, produce quick solutions to demands and combat uncertainties in the product development process. With the feedback of the customer who included in the process, it is worked towards marketing optimization, design and financial optimization.

Keywords: agile, design, missile, scrum

Procedia PDF Downloads 158
11905 Sensitivity and Uncertainty Analysis of One Dimensional Shape Memory Alloy Constitutive Models

Authors: A. B. M. Rezaul Islam, Ernur Karadogan

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Shape memory alloys (SMAs) are known for their shape memory effect and pseudoelasticity behavior. Their thermomechanical behaviors are modeled by numerous researchers using microscopic thermodynamic and macroscopic phenomenological point of view. Tanaka, Liang-Rogers and Ivshin-Pence models are some of the most popular SMA macroscopic phenomenological constitutive models. They describe SMA behavior in terms of stress, strain and temperature. These models involve material parameters and they have associated uncertainty present in them. At different operating temperatures, the uncertainty propagates to the output when the material is subjected to loading followed by unloading. The propagation of uncertainty while utilizing these models in real-life application can result in performance discrepancies or failure at extreme conditions. To resolve this, we used probabilistic approach to perform the sensitivity and uncertainty analysis of Tanaka, Liang-Rogers, and Ivshin-Pence models. Sobol and extended Fourier Amplitude Sensitivity Testing (eFAST) methods have been used to perform the sensitivity analysis for simulated isothermal loading/unloading at various operating temperatures. As per the results, it is evident that the models vary due to the change in operating temperature and loading condition. The average and stress-dependent sensitivity indices present the most significant parameters at several temperatures. This work highlights the sensitivity and uncertainty analysis results and shows comparison of them at different temperatures and loading conditions for all these models. The analysis presented will aid in designing engineering applications by eliminating the probability of model failure due to the uncertainty in the input parameters. Thus, it is recommended to have a proper understanding of sensitive parameters and the uncertainty propagation at several operating temperatures and loading conditions as per Tanaka, Liang-Rogers, and Ivshin-Pence model.

Keywords: constitutive models, FAST sensitivity analysis, sensitivity analysis, sobol, shape memory alloy, uncertainty analysis

Procedia PDF Downloads 136
11904 In Exile but Not at Peace: An Ethnography among Rwandan Army Deserters in South Africa

Authors: Florence Ncube

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This paper examines the military and post-military experiences of soldiers who deserted from the Rwanda Defence Force (RDF) and tried to make a living in South Africa. Because they are deserters, they try to hide their military identity, yet it is simultaneously somewhat coercively ascribed to them by the Rwandan state and can put them in potential danger. The paper attends to the constructions, experiences, practices, and subjective understanding of the deserters’ being in exile to examine how, under circumstances of perceived threat, these men navigate real or perceived state-sponsored surveillance and threat in non-military settings in South Africa where they have become potential political and disciplinary targets. To make sense of the deserters’ experiences in these circumstances, the paper stitches together a number of useful theoretical concepts, including Bourdieu’s (1992) theory of practice and Vigh’s (2009; 2018) concept of social navigation because no single approach can coherently analyze the specificity of this study. Conventional post-military literature privileges an understanding of army desertion as a malignancy and somewhat problematic. Little is known about the military and post-military experiences of deserters who believe that army desertion is in fact a building block towards achieving subjective peace, even in the context of exile. The paper argues that the presence of Rwandan state agents in South Africa strips the context of the exile of its capacity to provide the deserters with peace, safety, and security. This paper recenters army desertion in analyses of militarism, soldiering, and transition in African contexts and complicates commonsense understandings of army desertion which assume that it is entirely problematic. This paper is drawn from an ethnography conducted among 30 junior-rank Rwandan army deserters exiled in Johannesburg and Cape Town. The researcher employed life histories, in-depth interviews, and deep hangouts to collect data.

Keywords: army deserter, military, identity, exile, peacebuilding, South Africa

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11903 Three-Dimensional Computer Graphical Demonstration of Calcified Tissue and Its Clinical Significance

Authors: Itsuo Yokoyama, Rikako Kikuti, Miti Sekikawa, Tosinori Asai, Sarai Tsuyoshi

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Introduction: Vascular access for hemodialysis therapy is often difficult, even for experienced medical personnel. Ultrasound guided needle placement have been performed occasionally but is not always helpful in certain cases with complicated vascular anatomy. Obtaining precise anatomical knowledge of the vascular structure is important to prevent access-related complications. With augmented reality (AR) device such as AR glasses, the virtual vascular structure is shown superimposed on the actual patient vessels, thus enabling the operator to maneuver catheter placement easily with free both hands. We herein report our method of AR guided vascular access method in dialysis treatment Methods: Three dimensional (3D) object of the arm with arteriovenous fistula is computer graphically created with 3D software from the data obtained by computer tomography, ultrasound echogram, and image scanner. The 3D vascular object thus created is viewed on the screen of the AR digital display device (such as AR glass or iPad). The picture of the vascular anatomical structure becomes visible, which is superimposed over the real patient’s arm, thereby the needle insertion be performed under the guidance of AR visualization with ease. By this method, technical difficulty in catheter placement for dialysis can be lessened and performed safely. Considerations: Virtual reality technology has been applied in various fields and medical use is not an exception. Yet AR devices have not been widely used among medical professions. Visualization of the virtual vascular object can be achieved by creation of accurate three dimensional object with the help of computer graphical technique. Although our experience is limited, this method is applicable with relative easiness and our accumulating evidence has suggested that our method of vascular access with the use of AR can be promising.

Keywords: abdominal-aorta, calcification, extraskeletal, dialysis, computer graphics, 3DCG, CT, calcium, phosphorus

Procedia PDF Downloads 137
11902 Teleconnection between El Nino-Southern Oscillation and Seasonal Flow of the Surma River and Possibilities of Long Range Flood Forecasting

Authors: Monika Saha, A. T. M. Hasan Zobeyer, Nasreen Jahan

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El Nino-Southern Oscillation (ENSO) is the interaction between atmosphere and ocean in tropical Pacific which causes inconsistent warm/cold weather in tropical central and eastern Pacific Ocean. Due to the impact of climate change, ENSO events are becoming stronger in recent times, and therefore it is very important to study the influence of ENSO in climate studies. Bangladesh, being in the low-lying deltaic floodplain, experiences the worst consequences due to flooding every year. To reduce the catastrophe of severe flooding events, non-structural measures such as flood forecasting can be helpful in taking adequate precautions and steps. Forecasting seasonal flood with a longer lead time of several months is a key component of flood damage control and water management. The objective of this research is to identify the possible strength of teleconnection between ENSO and river flow of Surma and examine the potential possibility of long lead flood forecasting in the wet season. Surma is one of the major rivers of Bangladesh and is a part of the Surma-Meghna river system. In this research, sea surface temperature (SST) has been considered as the ENSO index and the lead time is at least a few months which is greater than the basin response time. The teleconnection has been assessed by the correlation analysis between July-August-September (JAS) flow of Surma and SST of Nino 4 region of the corresponding months. Cumulative frequency distribution of standardized JAS flow of Surma has also been determined as part of assessing the possible teleconnection. Discharge data of Surma river from 1975 to 2015 is used in this analysis, and remarkable increased value of correlation coefficient between flow and ENSO has been observed from 1985. From the cumulative frequency distribution of the standardized JAS flow, it has been marked that in any year the JAS flow has approximately 50% probability of exceeding the long-term average JAS flow. During El Nino year (warm episode of ENSO) this probability of exceedance drops to 23% and while in La Nina year (cold episode of ENSO) it increases to 78%. Discriminant analysis which is known as 'Categoric Prediction' has been performed to identify the possibilities of long lead flood forecasting. It has helped to categorize the flow data (high, average and low) based on the classification of predicted SST (warm, normal and cold). From the discriminant analysis, it has been found that for Surma river, the probability of a high flood in the cold period is 75% and the probability of a low flood in the warm period is 33%. A synoptic parameter, forecasting index (FI) has also been calculated here to judge the forecast skill and to compare different forecasts. This study will help the concerned authorities and the stakeholders to take long-term water resources decisions and formulate policies on river basin management which will reduce possible damage of life, agriculture, and property.

Keywords: El Nino-Southern Oscillation, sea surface temperature, surma river, teleconnection, cumulative frequency distribution, discriminant analysis, forecasting index

Procedia PDF Downloads 142
11901 Dynamic Test for Sway-Mode Buckling of Columns

Authors: Boris Blostotsky, Elia Efraim

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Testing of columns in sway mode is performed in order to determine the maximal allowable load limited by plastic deformations or their end connections and a critical load limited by columns stability. Motivation to determine accurate value of critical force is caused by its using as follow: - critical load is maximal allowable load for given column configuration and can be used as criterion of perfection; - it is used in calculation prescribed by standards for design of structural elements under combined action of compression and bending; - it is used for verification of theoretical analysis of stability at various end conditions of columns. In the present work a new non-destructive method for determination of columns critical buckling load in sway mode is proposed. The method allows performing measurements during the tests under loads that exceeds the columns critical load without losing its stability. The possibility of such loading is achieved by structure of the loading system. The system is performed as frame with rigid girder, one of the columns is the tested column and the other is additional two-hinged strut. Loading of the frame is carried out by the flexible traction element attached to the girder. The load applied on the tested column can achieve a values that exceed the critical load by choice of parameters of the traction element and the additional strut. The system lateral stiffness and the column critical load are obtained by the dynamic method. The experiment planning and the comparison between the experimental and theoretical values were performed based on the developed dependency of lateral stiffness of the system on vertical load, taking into account a semi-rigid connections of the column's ends. The agreement between the obtained results was established. The method can be used for testing of real full-size columns in industrial conditions.

Keywords: buckling, columns, dynamic method, semi-rigid connections, sway mode

Procedia PDF Downloads 307
11900 Study of a Complete Free Route Implementation in the European Airspace

Authors: Cesar A. Nava-Gaxiola, C. Barrado

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Harmonized with SESAR (Single European Sky Research) initiatives, a new concept related with airspace structures have been introduced in Europe, the Free Route Airspace. The key of free route is based in an airspace where users may freely plan a route between a defined entry and exit waypoint, with the possibility of routing via intermediate points, the free route flights remain subject to air traffic control (ATC) for the established separations. Free route airspace does not present anymore fixed airways to airspace users, as a consequence it brings a new paradigm for managing safe separations of aircrafts inside these airspace blocks . Nowadays, several European nations have been introduced the concept, some of them in a complete or partial stage, but finally offering limited benefits to airspace users for this condition. This research evaluates the future scenario of free route implementation across Europe, considering a unique airspace block configuration with a complete upper airspace with free route. The paper is centered in investigating the benefits for airspace users, and the study of possible increments of Air Traffic Controllers task loads with a full application. In this research, fast time simulations are carrying out for discovering how much flight time and distance aircrafts can save with an overall free route establishment. In the other side, the paper explains the evolution of conflicts derivate from possible separation losses between aircrafts in this new environment. Free route conflicts can emerges in any points of the airspace, requiring a great effort for solving it, in comparison with fixed airways, where conflicts normally were found by controllers in known waypoints, and they solved using the fixed network as reference. The airspace configuration modelled in this study take into account the actual navigation waypoints structure, moving into a future scenario, where new ones waypoints are added and new traffic flow patterns appears. In this sense, this research explores the advantages and unknown difficulties that a large scale application of free route concept can carry out in the European airspace.

Keywords: ATC conflicts, efficiency, free route airspace, SESAR

Procedia PDF Downloads 180
11899 Urinary Mucosal Cryoglobulin: A Review

Authors: Ibrahim M. S. Shnawa, Naeem R. R. Algebory

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The procedure for the assessment of the urinary mucosal cryoglobulin (UMCG) is being reviewed, testified and evaluated. The major features of UMCG are rather similar to that of serum cryoglobulin. Such evident similarities are forming the reality for the existence of the UMCG. There were seven characterizing criteria useable for the identification for UMCG. Upon matching them to the Irish criteria for serum cryoglobulin, some modifications are being proposed to the 16th standards that has been formulated and built as an Irish criterion. The existence of UMCG is being reported for the first time in human chronic infectious bacterial disease.

Keywords: urinary, mucosal, cryoglubulin, standard immunofixation

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11898 A Dissipative Particle Dynamics Study of a Capsule in Microfluidic Intracellular Delivery System

Authors: Nishanthi N. S., Srikanth Vedantam

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Intracellular delivery of materials has always proved to be a challenge in research and therapeutic applications. Usually, vector-based methods, such as liposomes and polymeric materials, and physical methods, such as electroporation and sonoporation have been used for introducing nucleic acids or proteins. Reliance on exogenous materials, toxicity, off-target effects was the short-comings of these methods. Microinjection was an alternative process which addressed the above drawbacks. However, its low throughput had hindered its adoption widely. Mechanical deformation of cells by squeezing them through constriction channel can cause the temporary development of pores that would facilitate non-targeted diffusion of materials. Advantages of this method include high efficiency in intracellular delivery, a wide choice of materials, improved viability and high throughput. This cell squeezing process can be studied deeper by employing simple models and efficient computational procedures. In our current work, we present a finite sized dissipative particle dynamics (FDPD) model to simulate the dynamics of the cell flowing through a constricted channel. The cell is modeled as a capsule with FDPD particles connected through a spring network to represent the membrane. The total energy of the capsule is associated with linear and radial springs in addition to constraint of the fixed area. By performing detailed simulations, we studied the strain on the membrane of the capsule for channels with varying constriction heights. The strain on the capsule membrane was found to be similar though the constriction heights vary. When strain on the membrane was correlated to the development of pores, we found higher porosity in capsule flowing in wider channel. This is due to localization of strain to a smaller region in the narrow constriction channel. But the residence time of the capsule increased as the channel constriction narrowed indicating that strain for an increased time will cause less cell viability.

Keywords: capsule, cell squeezing, dissipative particle dynamics, intracellular delivery, microfluidics, numerical simulations

Procedia PDF Downloads 138