Search results for: rare sensitive attribute
Commenced in January 2007
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Edition: International
Paper Count: 2952

Search results for: rare sensitive attribute

612 Comparative Study of Mutations Associated with Second Line Drug Resistance and Genetic Background of Mycobacterium tuberculosis Strains

Authors: Syed Beenish Rufai, Sarman Singh

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Background: Performance of Genotype MTBDRsl (Hain Life science GmbH Germany) for detection of mutations associated with second-line drug resistance is well known. However, less evidence regarding the association of mutations and genetic background of strains is known which, in the future, is essential for clinical management of anti-tuberculosis drugs in those settings where the probability of particular genotype is predominant. Material and Methods: During this retrospective study, a total of 259 MDR-TB isolates obtained from pulmonary TB patients were tested for second-line drug susceptibility testing (DST) using Genotype MTBDRsl VER 1.0 and compared with BACTEC MGIT-960 as a reference standard. All isolates were further characterized using spoligotyping. The spoligo patterns obtained were compared and analyzed using SITVIT_WEB. Results: Of total 259 MDR-TB isolates which were screened for second-line DST by Genotype MTBDRsl, mutations were found to be associated with gyrA, rrs and emb genes in 82 (31.6%), 2 (0.8%) and 90 (34.7%) isolates respectively. 16 (6.1%) isolates detected mutations associated with both FQ as well as to AG/CP drugs (XDR-TB). No mutations were detected in 159 (61.4%) isolates for corresponding gyrA and rrs genes. Genotype MTBDRsl showed a concordance of 96.4% for detection of sensitive isolates in comparison with second-line DST by BACTEC MGIT-960 and 94.1%, 93.5%, 60.5% and 50% for detection of XDR-TB, FQ, EMB, and AMK/CAP respectively. D94G was the most prevalent mutation found among (38 (46.4%)) OFXR isolates (37 FQ mono-resistant and 1 XDR-TB) followed by A90V (23 (28.1%)) (17 FQ mono-resistant and 6 XDR-TB). Among AG/CP resistant isolates A1401G was the most frequent mutation observed among (11 (61.1%)) isolates (2 AG/CP mono-resistant isolates and 9 XDR-TB isolates) followed by WT+A1401G (6 (33.3%)) and G1484T (1 (5.5%)) respectively. On spoligotyping analysis, Beijing strain (46%) was found to be the most predominant strain among pre-XDR and XDR TB isolates followed by CAS (30%), X (6%), Unique (5%), EAI and T each of 4%, Manu (3%) and Ural (2%) respectively. Beijing strain was found to be strongly associated with D94G (47.3%) and A90V mutations by (47.3%) and 34.8% followed by CAS strain by (31.6%) and 30.4% respectively. However, among AG/CP resistant isolates, only Beijing strain was found to be strongly associated with A1401G and WT+A1401G mutations by 54.5% and 50% respectively. Conclusion: Beijing strain was found to be strongly associated with the most prevalent mutations among pre-XDR and XDR TB isolates. Acknowledgments: Study was supported with Grant by All India Institute of Medical Sciences, New Delhi reference No. P-2012/12452.

Keywords: tuberculosis, line probe assay, XDR TB, drug susceptibility

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611 A Geochemical Perspective on A-Type Granites of Khanak and Devsar Areas, Haryana, India: Implications for Petrogenesis

Authors: Naresh Kumar, Radhika Sharma, A. K. Singh

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Granites from Khanak and Devsar areas, a part of Malani Igneous Suite (MIS) were investigated for their geochemical characteristics to understand the petrogenetic aspect of the research area. Neoproterozoic rocks of MIS are well exposed in Jhunjhunu, Jodhpur, Pali, Barmer, Jalor, Jaisalmer districts of Rajasthan and Bhiwani district of Haryana and also occur at Kirana hills of Pakistan. The MIS predominantly consists of acidic volcanic with acidic plutonic (granite of various types), mafic volcanic, mafic intrusive and minor amount of pyroclasts. Based on the field and petrographical studies, 28 samples were selected and analyzed for geochemical analysis of major, trace and rare earth elements at the Wadia Institute of Himalayan Geology, Dehradun by X-Ray Fluorescence Spectrometer (XRF) and ICP-MS (Inductively Coupled Plasma- Mass Spectrometry). Granites from the studied areas are categorized as grey, green and pink. Khanak granites consist of quartz, k-feldspar, plagioclase, and biotite as essential minerals and hematite, zircon, annite, monazite & rutile as accessory minerals. In Devsar granites, plagioclase is replaced by perthite and occurs as dominantly. Geochemically, granites from Khanak and Devsar areas exhibit typical A-type granites characteristics with their enrichment in SiO2, Na2O+K2O, Fe/Mg, Rb, Zr, Y, Th, U, REE (except Eu) and significant depletion in MgO, CaO, Sr, P, Ti, Ni, Cr, V and Eu suggested about A-type affinities in Northwestern Peninsular India. The amount of heat production (HP) in green and grey granites of Devsar area varies upto 9.68 & 11.70 μWm-3 and total heat generation unit (HGU) i.e. 23.04 & 27.86 respectively. Pink granites of Khanak area display a higher enrichment of HP (16.53 μWm-3) and HGU (39.37) than the granites from Devsar area. Overall, they have much higher values of HP and HGU than the average value of continental crust (3.8 HGU), which imply a possible linear relationship among the surface heat flow and crustal heat generation in the rocks of MIS. Chondrite-normalized REE patterns show enriched LREE, moderate to strong negative Eu anomalies and more or less flat heavy REE. In primitive mantle-normalized multi-element variation diagrams, the granites show pronounced depletions in the high-field-strength elements (HFSE) Nb, Zr, Sr, P, and Ti. Geochemical characteristics (major, trace and REE) along with the use of various discrimination schemes revealed their probable correspondence to magma derived from the crustal origin by a different degree of partial melting.

Keywords: A-type granite, neoproterozoic, Malani igneous suite, Khanak, Devsar

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610 Unveiling the Detailed Turn Off-On Mechanism of Carbon Dots to Different Sized MnO₂ Nanosensor for Selective Detection of Glutathione

Authors: Neeraj Neeraj, Soumen Basu, Banibrata Maity

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Glutathione (GSH) is one of the most important biomolecules having small molecular weight, which helps in various cellular functions like regulation of gene, xenobiotic metabolism, preservation of intracellular redox activities, signal transduction, etc. Therefore, the detection of GSH requires huge attention by using extremely selective and sensitive techniques. Herein, a rapid fluorometric nanosensor is designed by combining carbon dots (Cdots) and MnO₂ nanoparticles of different sizes for the detection of GSH. The bottom-up approach, i.e., microwave method, was used for the preparation of the water soluble and greatly fluorescent Cdots by using ascorbic acid as a precursor. MnO₂ nanospheres of different sizes (large, medium, and small) were prepared by varying the ratio of concentration of methionine and KMnO₄ at room temperature, which was confirmed by HRTEM analysis. The successive addition of MnO₂ nanospheres in Cdots results fluorescence quenching. From the fluorescence intensity data, Stern-Volmer quenching constant values (KS-V) were evaluated. From the fluorescence intensity and lifetime analysis, it was found that the degree of fluorescence quenching of Cdots followed the order: large > medium > small. Moreover, fluorescence recovery studies were also performed in the presence of GSH. Fluorescence restoration studies also show the order of turn on follows the same order, i.e., large > medium > small, which was also confirmed by quantum yield and lifetime studies. The limits of detection (LOD) of GSH in presence of Cdots@different sized MnO₂ nanospheres were also evaluated. It was observed thatLOD values were in μM region and lowest in case of large MnO₂ nanospheres. The separation distance (d) between Cdots and the surface of different MnO₂ nanospheres was determined. The d values increase with increase in the size of the MnO₂ nanospheres. In summary, the synthesized Cdots@MnO₂ nanocomposites acted as a rapid, simple, economical as well as environmental-friendly nanosensor for the detection of GSH.

Keywords: carbon dots, fluorescence, glutathione, MnO₂ nanospheres, turn off-on

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609 An Investigation on MgAl₂O₄ Based Mould System in Investment Casting Titanium Alloy

Authors: Chen Yuan, Nick Green, Stuart Blackburn

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The investment casting process offers a great freedom of design combined with the economic advantage of near net shape manufacturing. It is widely used for the production of high value precision cast parts in particularly in the aerospace sector. Various combinations of materials have been used to produce the ceramic moulds, but most investment foundries use a silica based binder system in conjunction with fused silica, zircon, and alumino-silicate refractories as both filler and coarse stucco materials. However, in the context of advancing alloy technologies, silica based systems are struggling to keep pace, especially when net-shape casting titanium alloys. Study has shown that the casting of titanium based alloys presents considerable problems, including the extensive interactions between the metal and refractory, and the majority of metal-mould interaction is due to reduction of silica, present as binder and filler phases, by titanium in the molten state. Cleaner, more refractory systems are being devised to accommodate these changes. Although yttria has excellent chemical inertness to titanium alloy, it is not very practical in a production environment combining high material cost, short slurry life, and poor sintering properties. There needs to be a cost effective solution to these issues. With limited options for using pure oxides, in this work, a silica-free magnesia spinel MgAl₂O₄ was used as a primary coat filler and alumina as a binder material to produce facecoat in the investment casting mould. A comparison system was also studied with a fraction of the rare earth oxide Y₂O₃ adding into the filler to increase the inertness. The stability of the MgAl₂O₄/Al₂O₃ and MgAl₂O₄/Y₂O₃/Al₂O₃ slurries was assessed by tests, including pH, viscosity, zeta-potential and plate weight measurement, and mould properties such as friability were also measured. The interaction between the face coat and titanium alloy was studied by both a flash re-melting technique and a centrifugal investment casting method. The interaction products between metal and mould were characterized using x-ray diffraction (XRD), scanning electron microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDS). The depth of the oxygen hardened layer was evaluated by micro hardness measurement. Results reveal that introducing a fraction of Y₂O₃ into magnesia spinel can significantly increase the slurry life and reduce the thickness of hardened layer during centrifugal casting.

Keywords: titanium alloy, mould, MgAl₂O₄, Y₂O₃, interaction, investment casting

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608 Benign Recurrent Unilateral Abducens (6th) Nerve Palsy in 14 Months Old Girl: A Case Report

Authors: Khaled Alabduljabbar

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Background: Benign, isolated, recurrent sixth nerve palsy is very rare in children. Here we report a case of recurrent abducens nerve palsy with no obvious etiology. It is a diagnosis of exclusion. A recurrent benign form of 6th nerve palsy, a rarer still palsy, has been described in the literature, and it is of most likely secondary to inflammatory causes, e.g, following viral and bacterial infections. Purpose: To present a case of 14 months old girl with recurrent attacks of isolated left sixth cranial nerve palsy following upper respiratory tract infection. Observation: The patient presented to opthalmology clinic with sudden onset of inward deviation (esotropia) of the left eye with a compensatory left face turn one week following signs of upper respiratory tract infection. Ophthalmological examination revealed large angle esotropia of the left eye in primary position, with complete limitation of abduction of the left eye, no palpebral fissure changes, and abnormal position of the head (left face turn). Visual acuity was normal, and no significant refractive error on cycloplegic refraction for her age. Fundus examination was normal with no evidence of papilledema. There was no relative afferent pupillary defect (RAPD) and no anisocoria. Past medical history and family history were unremarkable, with no history of convulsion attacks or head trauma. Additional workout include CBC. Erythrocyte sedimentation rate, Urgent magnetic resonance imaging (MRI), and angiography of the brain were performed and demonstrated the absence of intracranial and orbital lesions. Referral to pediatric neurologist was also done and concluded no significant finding. The patient showed improvement of the left sixth cranial nerve palsy and left face turn over a period of two months. Seven months since the first attack, she experienced a recurrent attack of left eye esotropia with left face turn concurrent with URTI. The rest of eye examination was again unremarkable. CT scan and MRI scan of brain and orbit were performed and showed only signs of sinusitis with no intracranial pathology. The palsy resolved spontaneously within two months. A third episode of left 6th nerve palsy occurred 6 months later, whichrecovered over one month. Examination and neuroimagingwere unremarkable. A diagnosis of benign recurrent left 6th cranial nerve palsy was made. Conclusion: Benign sixth cranial nerve palsy is always a diagnosis of exclusion given the more serious and life-threatening alternative causes. It seems to have a good prognosis with only supportive measures. The likelihood of benign 6th cranial nerve palsy to resolve completely and spontaneously is high. Observation for at least 6 months without intervention is advisable.

Keywords: 6th nerve pasy, abducens nerve pasy, recurrent nerve palsy, cranial nerve palsy

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607 Use of Smartphones in 6th and 7th Grade (Elementary Schools) in Istria: Pilot Study

Authors: Maja Ruzic-Baf, Vedrana Keteles, Andrea Debeljuh

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Younger and younger children are now using a smartphone, a device which has become ‘a must have’ and the life of children would be almost ‘unthinkable’ without one. Devices are becoming lighter and lighter but offering an array of options and applications as well as the unavoidable access to the Internet, without which it would be almost unusable. Numerous features such as taking of photographs, listening to music, information search on the Internet, access to social networks, usage of some of the chatting and messaging services, are only some of the numerous features offered by ‘smart’ devices. They have replaced the alarm clock, home phone, camera, tablet and other devices. Their use and possession have become a part of the everyday image of young people. Apart from the positive aspects, the use of smartphones has also some downsides. For instance, free time was usually spent in nature, playing, doing sports or other activities enabling children an adequate psychophysiological growth and development. The greater usage of smartphones during classes to check statuses on social networks, message your friends, play online games, are just some of the possible negative aspects of their application. Considering that the age of the population using smartphones is decreasing and that smartphones are no longer ‘foreign’ to children of pre-school age (smartphones are used at home or in coffee shops or shopping centers while waiting for their parents, playing video games often inappropriate to their age), particular attention must be paid to a very sensitive group, the teenagers who almost never separate from their ‘pets’. This paper is divided into two sections, theoretical and empirical ones. The theoretical section gives an overview of the pros and cons of the usage of smartphones, while the empirical section presents the results of a research conducted in three elementary schools regarding the usage of smartphones and, specifically, their usage during classes, during breaks and to search information on the Internet, check status updates and 'likes’ on the Facebook social network.

Keywords: education, smartphone, social networks, teenagers

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606 Development of High-Efficiency Down-Conversion Fluoride Phosphors to Increase the Efficiency of Solar Panels

Authors: S. V. Kuznetsov, M. N. Mayakova, V. Yu. Proydakova, V. V. Pavlov, A. S. Nizamutdinov, O. A. Morozov, V. V. Voronov, P. P. Fedorov

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Increase in the share of electricity received by conversion of solar energy results in the reduction of the industrial impact on the environment from the use of the hydrocarbon energy sources. One way to increase said share is to improve the efficiency of solar energy conversion in silicon-based solar panels. Such efficiency increase can be achieved by transferring energy from sunlight-insensitive areas of work of silicon solar panels to the area of their photoresistivity. To achieve this goal, a transition to new luminescent materials with the high quantum yield of luminescence is necessary. Improvement in the quantum yield can be achieved by quantum cutting, which allows obtaining a quantum yield of down conversion of more than 150% due to the splitting of high-energy photons of the UV spectral range into lower-energy photons of the visible and near infrared spectral ranges. The goal of present work is to test approach of excitation through sensibilization of 4f-4f fluorescence of Yb3+ by various RE ions absorbing in UV and Vis spectral ranges. One of promising materials for quantum cutting luminophores are fluorides. In our investigation we have developed synthesis of nano- and submicron powders of calcium fluoride and strontium doped with rare-earth elements (Yb: Ce, Yb: Pr, Yb: Eu) of controlled dimensions and shape by co-precipitation from water solution technique. We have used Ca(NO3)2*4H2O, Sr(NO3)2, HF, NH4F as precursors. After initial solutions of nitrates were prepared they have been mixed with fluorine containing solution by dropwise manner. According to XRD data, the synthesis resulted in single phase samples with fluorite structure. By means of SEM measurements, we have confirmed spherical morphology and have determined sizes of particles (50-100 nm after synthesis and 150-300 nm after calcination). Temperature of calcination appeared to be 600°C. We have investigated the spectral-kinetic characteristics of above mentioned compounds. Here the diffuse reflection and laser induced fluorescence spectra of Yb3+ ions excited at around 4f-4f and 4f-5d transitions of Pr3+, Eu3+ and Ce3+ ions in the synthesized powders are reported. The investigation of down conversion luminescence capability of synthesized compounds included measurements of fluorescence decays and quantum yield of 2F5/2-2F7/2 fluorescence of Yb3+ ions as function of Yb3+ and sensitizer contents. An optimal chemical composition of CaF2-YbF3- LnF3 (Ln=Ce, Eu, Pr), SrF2-YbF3-LnF3 (Ln=Ce, Eu, Pr) micro- and nano- powders according to criteria of maximal IR fluorescence yield is proposed. We suppose that investigated materials are prospective in solar panels improvement applications. Work was supported by Russian Science Foundation grant #17-73- 20352.

Keywords: solar cell, fluorides, down-conversion luminescence, maximum quantum yield

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605 Preservation of High Quality Fruit Products: Microwave Freeze Drying as a Substitute for the Conventional Freeze Drying Process

Authors: Sabine Ambros, Ulrich Kulozik

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Berries such as blue- and raspberries belong to the most valuable fruits. To preserve the characteristic flavor and the high contents of vitamins and anthocyanins, the very sensitive berries are usually dried by lyophilization. As this method is very time- and energy-consuming, the dried fruit is extremely expensive. However, healthy snack foods are growing in popularity. Especially dried fruit free of any additives or additional sugar are more and more asked for. To make these products affordable, the fruits have to be dried by a method that is more energy-efficient than freeze drying but reveals the same high product quality. The additional insertion of microwaves to a freeze drying process was examined in this work to overcome the inconveniences of freeze drying. As microwaves penetrate the product volumetrically, sublimation takes place simultaneously all over the product and leads to a many times shorter process duration. A range of microwave and pressure settings was applied to find the optimum drying condition. The influence of the process parameters microwave power and chamber pressure on drying kinetics, product temperature and product quality was investigated to find the best condition for an energy-efficient process with high product quality. The product quality was evaluated by rehydration capacitiy, crispiness, shrinkage, color, vitamin C content and antioxidative capacity. The conclusion could be drawn that microwave freeze dried berries were almost equal to freeze dried fruit in all measured quality parameters or even could overcome it. Additionally, sensory evaluations could confirm the analytical studies. Drying time could be reduced by more than 75% at much lower energy consumption rates. Thus, an energy-efficient and cost saving method compared to the conventional freeze drying technique for the gentle production of tasty fruit or vegetable snacks has been found. This technique will make dried high-quality snacks available for many of consumers.

Keywords: blueberries, freeze drying, microwave freeze drying, process parameters, product quality

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604 Using 3D Satellite Imagery to Generate a High Precision Canopy Height Model

Authors: M. Varin, A. M. Dubois, R. Gadbois-Langevin, B. Chalghaf

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Good knowledge of the physical environment is essential for an integrated forest planning. This information enables better forecasting of operating costs, determination of cutting volumes, and preservation of ecologically sensitive areas. The use of satellite images in stereoscopic pairs gives the capacity to generate high precision 3D models, which are scale-adapted for harvesting operations. These models could represent an alternative to 3D LiDAR data, thanks to their advantageous cost of acquisition. The objective of the study was to assess the quality of stereo-derived canopy height models (CHM) in comparison to a traditional LiDAR CHM and ground tree-height samples. Two study sites harboring two different forest stand types (broadleaf and conifer) were analyzed using stereo pairs and tri-stereo images from the WorldView-3 satellite to calculate CHM. Acquisition of multispectral images from an Unmanned Aerial Vehicle (UAV) was also realized on a smaller part of the broadleaf study site. Different algorithms using two softwares (PCI Geomatica and Correlator3D) with various spatial resolutions and band selections were tested to select the 3D modeling technique, which offered the best performance when compared with LiDAR. In the conifer study site, the CHM produced with Corelator3D using only the 50-cm resolution panchromatic band was the one with the smallest Root-mean-square deviation (RMSE: 1.31 m). In the broadleaf study site, the tri-stereo model provided slightly better performance, with an RMSE of 1.2 m. The tri-stereo model was also compared to the UAV, which resulted in an RMSE of 1.3 m. At individual tree level, when ground samples were compared to satellite, lidar, and UAV CHM, RMSE were 2.8, 2.0, and 2.0 m, respectively. Advanced analysis was done for all of these cases, and it has been noted that RMSE is reduced when the canopy cover is higher when shadow and slopes are lower and when clouds are distant from the analyzed site.

Keywords: very high spatial resolution, satellite imagery, WorlView-3, canopy height models, CHM, LiDAR, unmanned aerial vehicle, UAV

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603 Effect of Geometric Imperfections on the Vibration Response of Hexagonal Lattices

Authors: P. Caimmi, E. Bele, A. Abolfathi

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Lattice materials are cellular structures composed of a periodic network of beams. They offer high weight-specific mechanical properties and lend themselves to numerous weight-sensitive applications. The periodic internal structure responds to external vibrations through characteristic frequency bandgaps, making these materials suitable for the reduction of noise and vibration. However, the deviation from architectural homogeneity, due to, e.g., manufacturing imperfections, has a strong influence on the mechanical properties and vibration response of these materials. In this work, we present results on the influence of geometric imperfections on the vibration response of hexagonal lattices. Three classes of geometrical variables are used: the characteristics of the architecture (relative density, ligament length/cell size ratio), imperfection type (degree of non-periodicity, cracks, hard inclusions) and defect morphology (size, distribution). Test specimens with controlled size and distribution of imperfections are manufactured through selective laser sintering. The Frequency Response Functions (FRFs) in the form of accelerance are measured, and the modal shapes are captured through a high-speed camera. The finite element method is used to provide insights on the extension of these results to semi-infinite lattices. An updating procedure is conducted to increase the reliability of numerical simulation results compared to experimental measurements. This is achieved by updating the boundary conditions and material stiffness. Variations in FRFs of periodic structures due to changes in the relative density of the constituent unit cell are analysed. The effects of geometric imperfections on the dynamic response of periodic structures are investigated. The findings can be used to open up the opportunity for tailoring these lattice materials to achieve optimal amplitude attenuations at specific frequency ranges.

Keywords: lattice architectures, geometric imperfections, vibration attenuation, experimental modal analysis

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602 Large-Scale Screening for Membrane Protein Interactions Involved in Platelet-Monocyte Interactions

Authors: Yi Sun, George Ed Rainger, Steve P. Watson

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Background: Beyond the classical roles in haemostasis and thrombosis, platelets are important in the initiation and development of various thrombo-inflammatory diseases. In atherosclerosis and deep vein thrombosis, for example, platelets bridge monocytes with endothelium and form heterotypic aggregates with monocytes in the circulation. This can alter monocyte phenotype by inducing their activation, stimulating adhesion and migration. These interactions involve cell surface receptor-ligand pairs on both cells. This list is likely incomplete as new interactions of importance to platelet biology are continuing to be discovered as illustrated by our discovery of PEAR-1 binding to FcεR1α. Results: We have developed a highly sensitive avidity-based assay to identify novel extracellular interactions among 126 recombinantly-expressed platelet cell surface and secreted proteins involved in platelet aggregation. In this study, we will use this method to identify novel platelet-monocyte interactions. We aim to identify ligands for orphan receptors and novel partners of well-known proteins. Identified interactions will be studied in preliminary functional assays to demonstrate relevance to the inflammatory processes supporting atherogenesis. Conclusions: Platelet-monocyte interactions are essential for the development of thromboinflammatory disease. Up until relatively recently, technologies only allow us to limit our studies on each individual protein interaction at a single time. These studies propose for the first time to study the cell surface platelet-monocyte interactions in a systematic large-scale approach using a reliable screening method we have developed. If successful, this will likely to identify previously unknown ligands for important receptors that will be investigated in details and also provide a list of novel interactions for the field. This should stimulate studies on developing alternative therapeutic strategies to treat vascular inflammatory disorders such as atherosclerosis, DVT and sepsis and other clinically important inflammatory conditions.

Keywords: membrane proteins, large-scale screening, platelets, recombinant expression

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601 The Effects of Cardiovascular Risk on Age-Related Cognitive Decline in Healthy Older Adults

Authors: A. Badran, M. Hollocks, H. Markus

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Background: Common risk factors for cardiovascular disease are associated with age-related cognitive decline. There has been much interest in treating modifiable cardiovascular risk factors in the hope of reducing cognitive decline. However, there is currently no validated neuropsychological test to assess the subclinical cognitive effects of vascular risk. The Brief Memory and Executive Test (BMET) is a clinical screening tool, which was originally designed to be sensitive and specific to Vascular Cognitive Impairment (VCI), an impairment characterised by decline in frontally-mediated cognitive functions (e.g. Executive Function and Processing Speed). Objective: To cross-sectionally assess the validity of the BMET as a measure of the subclinical effects of vascular risk on cognition, in an otherwise healthy elderly cohort. Methods: Data from 346 participants (57 ± 10 years) without major neurological or psychiatric disorders were included in this study, gathered as part of a previous multicentre validation study for the BMET. Framingham Vascular Age was used as a surrogate measure of vascular risk, incorporating several established risk factors. Principal Components Analysis of the subtests was used to produce common constructs: an index for Memory and another for Executive Function/Processing Speed. Univariate General Linear models were used to relate Vascular Age to performance on Executive Function/Processing Speed and Memory subtests of the BMET, adjusting for Age, Premorbid Intelligence and Ethnicity. Results: Adverse vascular risk was associated with poorer performance on both the Memory and Executive Function/Processing Speed indices, adjusted for Age, Premorbid Intelligence and Ethnicity (p=0.011 and p<0.001, respectively). Conclusions: Performance on the BMET reflects the subclinical effects of vascular risk on cognition, in age-related cognitive decline. Vascular risk is associated with decline in both Executive Function/Processing Speed and Memory groups of subtests. Future studies are needed to explore whether treating vascular risk factors can effectively reduce age-related cognitive decline.

Keywords: age-related cognitive decline, vascular cognitive impairment, subclinical cerebrovascular disease, cognitive aging

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600 Wharton's Jelly-Derived Mesenchymal Stem Cells Modulate Heart Rate Variability and Improve Baroreflex Sensitivity in Septic Rats

Authors: Cóndor C. José, Rodrigues E. Camila, Noronha L. Irene, Dos Santos Fernando, Irigoyen M. Claudia, Andrade Lúcia

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Sepsis induces alterations in hemodynamics and autonomic nervous system (ASN). The autonomic activity can be calculated by measuring heart rate variability (HRV) that represents the complex interplay between ASN and cardiac pacemaker cells. Wharton’s jelly mesenchymal stem cells (WJ-MSCs) are known to express genes and secreted factors involved in neuroprotective and immunological effects, also to improve the survival in experimental septic animals. We hypothesized, that WJ-MSCs present an important role in the autonomic activity and in the hemodynamic effects in a cecal ligation and puncture (CLP) model of sepsis. Methods: We used flow cytometry to evaluate WJ-MSCs phenotypes. We divided Wistar rats into groups: sham (shamoperated); CLP; and CLP+MSC (106 WJ-MSCs, i.p., 6 h after CLP). At 24 h post-CLP, we recorded the systolic arterial pressure (SAP) and heart rate (HR) over 20 min. The spectral analysis of HR and SAP; also the spontaneous baroreflex sensitivity (measure by bradycardic and tachycardic responses) were evaluated after recording. The one-way ANOVA and the post hoc Student– Newman– Keuls tests (P< 0.05) were used to data comparison Results: WJ-MSCs were negative for CD3, CD34, CD45 and HLA-DR, whereas they were positive for CD73, CD90 and CD105. The CLP group showed a reduction in variance of overall variability and in high-frequency power of HR (heart parasympathetic activity); furthermore, there is a low-frequency reduction of SAP (blood vessels sympathetic activity). The treatment with WJ-MSCs improved the autonomic activity by increasing the high and lowfrequency power; and restore the baroreflex sensitive. Conclusions: WJ-MSCs attenuate the impairment of autonomic control of the heart and vessels and might therefore play a protective role in sepsis. (Supported by FAPESP).

Keywords: baroreflex response, heart rate variability, sepsis, wharton’s jelly-derived mesenchymal stem cells

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599 Engineering of Reagentless Fluorescence Biosensors Based on Single-Chain Antibody Fragments

Authors: Christian Fercher, Jiaul Islam, Simon R. Corrie

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Fluorescence-based immunodiagnostics are an emerging field in biosensor development and exhibit several advantages over traditional detection methods. While various affinity biosensors have been developed to generate a fluorescence signal upon sensing varying concentrations of analytes, reagentless, reversible, and continuous monitoring of complex biological samples remains challenging. Here, we aimed to genetically engineer biosensors based on single-chain antibody fragments (scFv) that are site-specifically labeled with environmentally sensitive fluorescent unnatural amino acids (UAA). A rational design approach resulted in quantifiable analyte-dependent changes in peak fluorescence emission wavelength and enabled antigen detection in vitro. Incorporation of a polarity indicator within the topological neighborhood of the antigen-binding interface generated a titratable wavelength blueshift with nanomolar detection limits. In order to ensure continuous analyte monitoring, scFv candidates with fast binding and dissociation kinetics were selected from a genetic library employing a high-throughput phage display and affinity screening approach. Initial rankings were further refined towards rapid dissociation kinetics using bio-layer interferometry (BLI) and surface plasmon resonance (SPR). The most promising candidates were expressed, purified to homogeneity, and tested for their potential to detect biomarkers in a continuous microfluidic-based assay. Variations of dissociation kinetics within an order of magnitude were achieved without compromising the specificity of the antibody fragments. This approach is generally applicable to numerous antibody/antigen combinations and currently awaits integration in a wide range of assay platforms for one-step protein quantification.

Keywords: antibody engineering, biosensor, phage display, unnatural amino acids

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598 Studies on Knockdown Resistance Mutations in Aedes aegypti and Aedes albopictus in India

Authors: Neera Kapoor

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Background: Knockdown Resistance (KDR) is one of the mechanisms of insecticide resistance in insects caused by the reduced target site sensitivity i.e. voltage gated sodium channel (VGSC) rendering it less sensitive to the toxic effects of DDT and pyrethroids. In this study, we evaluated insecticide susceptibility and its underlying KDR mechanism in eight Ae. aegypti and five Ae. albopictus field populations. Methodology: Field population was collected from four different geographical regions of India covering 18 districts of ten states. For genotyping of twelve KDR alleles in Ae. aegypti field populations, three PCR based assays were used; with DNA sequencing; ASPCR; PCR-RFLP. Genomic DNA was isolated, and three partial domains (II, III, and IV) of VGSC were amplified and sequenced. Results: Molecular screening for common KDR mutations, revealed the presence of five mutations viz. S989P, V1016G, T1520I, F1534C/L. Two novel mutations were observed, first at T1520 (ACC) residue where a C > T substitution at the second position of codon results in amino acid change to Isoleucine (ATC). Second mutation was an alternative point mutation at F1534 (TTC) residue where a substitution of T > C at the first position of codon results in an amino acid change to Leucine (CTC). ASPCRs were not accurate, so three PCR-RFLP assays were developed for genotyping of five KDR alleles in Ae. aegypti; viz. T1520I, F1534C/L. Representative samples of all genotypes (n=200) were sequenced to validate the newly developed PCR based assays for Ae. aegypti. Genotyping results showed that 989P is linked to 1016G and novel mutation 1520I was always found with 1534C allele. Conclusion: Present study confirmed the presence of DDT and pyrethroid resistance among Ae. aegypti populations in India and for the first time reported KDR mutations in this species from India including two novel mutations. Results of present study lead us to infer that, at least five KDR mutations (S989P, V1016G, T1530I, F1534C, and F1534L) can be seen as a potential marker for DDT/pyrethroid resistance.

Keywords: F1534C, F1534L, S989P, T1530I, V1016G

Procedia PDF Downloads 194
597 Unsupervised Learning and Similarity Comparison of Water Mass Characteristics with Gaussian Mixture Model for Visualizing Ocean Data

Authors: Jian-Heng Wu, Bor-Shen Lin

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The temperature-salinity relationship is one of the most important characteristics used for identifying water masses in marine research. Temperature-salinity characteristics, however, may change dynamically with respect to the geographic location and is quite sensitive to the depth at the same location. When depth is taken into consideration, however, it is not easy to compare the characteristics of different water masses efficiently for a wide range of areas of the ocean. In this paper, the Gaussian mixture model was proposed to analyze the temperature-salinity-depth characteristics of water masses, based on which comparison between water masses may be conducted. Gaussian mixture model could model the distribution of a random vector and is formulated as the weighting sum for a set of multivariate normal distributions. The temperature-salinity-depth data for different locations are first used to train a set of Gaussian mixture models individually. The distance between two Gaussian mixture models can then be defined as the weighting sum of pairwise Bhattacharyya distances among the Gaussian distributions. Consequently, the distance between two water masses may be measured fast, which allows the automatic and efficient comparison of the water masses for a wide range area. The proposed approach not only can approximate the distribution of temperature, salinity, and depth directly without the prior knowledge for assuming the regression family, but may restrict the complexity by controlling the number of mixtures when the amounts of samples are unevenly distributed. In addition, it is critical for knowledge discovery in marine research to represent, manage and share the temperature-salinity-depth characteristics flexibly and responsively. The proposed approach has been applied to a real-time visualization system of ocean data, which may facilitate the comparison of water masses by aggregating the data without degrading the discriminating capabilities. This system provides an interface for querying geographic locations with similar temperature-salinity-depth characteristics interactively and for tracking specific patterns of water masses, such as the Kuroshio near Taiwan or those in the South China Sea.

Keywords: water mass, Gaussian mixture model, data visualization, system framework

Procedia PDF Downloads 146
596 Silicon-Photonic-Sensor System for Botulinum Toxin Detection in Water

Authors: Binh T. T. Nguyen, Zhenyu Li, Eric Yap, Yi Zhang, Ai-Qun Liu

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Silicon-photonic-sensor system is an emerging class of analytical technologies that use evanescent field wave to sensitively measure the slight difference in the surrounding environment. The wavelength shift induced by local refractive index change is used as an indicator in the system. These devices can be served as sensors for a wide variety of chemical or biomolecular detection in clinical and environmental fields. In our study, a system including a silicon-based micro-ring resonator, microfluidic channel, and optical processing is designed, fabricated for biomolecule detection. The system is demonstrated to detect Clostridium botulinum type A neurotoxin (BoNT) in different water sources. BoNT is one of the most toxic substances known and relatively easily obtained from a cultured bacteria source. The toxin is extremely lethal with LD50 of about 0.1µg/70kg intravenously, 1µg/ 70 kg by inhalation, and 70µg/kg orally. These factors make botulinum neurotoxins primary candidates as bioterrorism or biothreat agents. It is required to have a sensing system which can detect BoNT in a short time, high sensitive and automatic. For BoNT detection, silicon-based micro-ring resonator is modified with a linker for the immobilization of the anti-botulinum capture antibody. The enzymatic reaction is employed to increase the signal hence gains sensitivity. As a result, a detection limit to 30 pg/mL is achieved by our silicon-photonic sensor within a short period of 80 min. The sensor also shows high specificity versus the other type of botulinum. In the future, by designing the multifunctional waveguide array with fully automatic control system, it is simple to simultaneously detect multi-biomaterials at a low concentration within a short period. The system has a great potential to apply for online, real-time and high sensitivity for the label-free bimolecular rapid detection.

Keywords: biotoxin, photonic, ring resonator, sensor

Procedia PDF Downloads 117
595 Barriers to Access among Indigenous Women Seeking Prenatal Care: A Literature Review

Authors: Zarish Jawad, Nikita Chugh, Karina Dadar

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Introduction: This paper aims to identify barriers indigenous women face in accessing prenatal care in Canada. It explores the differences in prenatal care received between indigenous and non-indigenous women. The objective is to look at changes or programs in Canada's healthcare system to reduce barriers to accessing safe prenatal care for indigenous women. Methods: A literature search of 12 papers was conducted using the following databases: PubMed, Medline, OVID, Google Scholar, and ScienceDirect. The studies included were written in English only, including indigenous females between the age of 19-35, and review articles were excluded. Participants in the studies examined did not have any severe underlying medical conditions for the duration of the study, and study designs included in the review are prospective cohort, cross-sectional, case report, and case-control studies. Results: Among all the barriers Indigenous women face in accessing prenatal care, the three most significant barriers Indigenous women face include a lack of culturally safe prenatal care, lack of services in the Indigenous community, proximity of prenatal facilities to Indigenous communities and costs of transportation. Discussion: The study found three significant barriers indigenous women face in accessing prenatal care in Canada; the geographical distribution of healthcare facilities, distrust between patients and healthcare professionals, and cultural sensitivity. Some of the suggested solutions include building more birthing and prenatal care facilities in rural areas for indigenous women, educating healthcare professionals on culturally sensitive healthcare, and involving indigenous people in the decision-making process to reduce distrust and power imbalances. Conclusion: The involvement of indigenous women and community leaders is important in making decisions regarding the implementation of effective healthcare and prenatal programs for indigenous women. However, further research is required to understand the effectiveness of the solutions and the barriers that make prenatal care less accessible for indigenous women in Canada.

Keywords: indigenous, maternal health, prenatal care, barriers

Procedia PDF Downloads 152
594 Gradient Boosted Trees on Spark Platform for Supervised Learning in Health Care Big Data

Authors: Gayathri Nagarajan, L. D. Dhinesh Babu

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Health care is one of the prominent industries that generate voluminous data thereby finding the need of machine learning techniques with big data solutions for efficient processing and prediction. Missing data, incomplete data, real time streaming data, sensitive data, privacy, heterogeneity are few of the common challenges to be addressed for efficient processing and mining of health care data. In comparison with other applications, accuracy and fast processing are of higher importance for health care applications as they are related to the human life directly. Though there are many machine learning techniques and big data solutions used for efficient processing and prediction in health care data, different techniques and different frameworks are proved to be effective for different applications largely depending on the characteristics of the datasets. In this paper, we present a framework that uses ensemble machine learning technique gradient boosted trees for data classification in health care big data. The framework is built on Spark platform which is fast in comparison with other traditional frameworks. Unlike other works that focus on a single technique, our work presents a comparison of six different machine learning techniques along with gradient boosted trees on datasets of different characteristics. Five benchmark health care datasets are considered for experimentation, and the results of different machine learning techniques are discussed in comparison with gradient boosted trees. The metric chosen for comparison is misclassification error rate and the run time of the algorithms. The goal of this paper is to i) Compare the performance of gradient boosted trees with other machine learning techniques in Spark platform specifically for health care big data and ii) Discuss the results from the experiments conducted on datasets of different characteristics thereby drawing inference and conclusion. The experimental results show that the accuracy is largely dependent on the characteristics of the datasets for other machine learning techniques whereas gradient boosting trees yields reasonably stable results in terms of accuracy without largely depending on the dataset characteristics.

Keywords: big data analytics, ensemble machine learning, gradient boosted trees, Spark platform

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593 Evaluation and Risk Assessment of Heavy Metals Pollution Using Edible Crabs, Based on Food Intended for Human Consumption

Authors: Nayab Kanwal, Noor Us Saher

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The management and utilization of food resources is becoming a big issue due to rapid urbanization, wastage and non-sustainable use of food, especially in developing countries. Therefore, the use of seafood as alternative sources is strongly promoted worldwide. Marine pollution strongly affects marine organisms, which ultimately decreases their export quality. The monitoring of contamination in marine organisms is a good indicator of the environmental quality as well as seafood quality. Monitoring the accumulation of chemical elements within various tissues of organisms has become a useful tool to survey current or chronic levels of heavy metal exposure within an environment. In this perspective, this study was carried out to compare the previous and current levels (Year 2012 and 2014) of heavy metals (Cd, Pb, Cr, Cu and Zn) in crabs marketed in Karachi and to estimate the toxicological risk associated with their intake. The accumulation of metals in marine organisms, both essential (Cu and Zn) and toxic (Pb, Cd and Cr), natural and anthropogenic, is an actual food safety issue. Significant (p>0.05) variations in metal concentrations were found in all crab species between the two years, with most of the metals showing high accumulation in 2012. For toxicological risk assessment, EWI (Estimated weekly intake), Target Hazard quotient (THQ) and cancer risk (CR) were also assessed and high EWI, Non- cancer risk (THQ < 1) showed that there is no serious threat associated with the consumption of shellfish species on Karachi coast. The Cancer risk showed the highest risk from Cd and Pb pollution if consumed in excess. We summarize key environmental health research on health effects associated with exposure to contaminated seafood. It could be concluded that considering the Pakistan coast, these edible species may be sensitive and vulnerable to the adverse effects of environmental contaminants; more attention should be paid to the Pb and Cd metal bioaccumulation and to toxicological risks to seafood and consumers.

Keywords: cancer risk, edible crabs, heavy metals pollution, risk assessment

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592 Enhancing Healthcare Data Protection and Security

Authors: Joseph Udofia, Isaac Olufadewa

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Everyday, the size of Electronic Health Records data keeps increasing as new patients visit health practitioner and returning patients fulfil their appointments. As these data grow, so is their susceptibility to cyber-attacks from criminals waiting to exploit this data. In the US, the damages for cyberattacks were estimated at $8 billion (2018), $11.5 billion (2019) and $20 billion (2021). These attacks usually involve the exposure of PII. Health data is considered PII, and its exposure carry significant impact. To this end, an enhancement of Health Policy and Standards in relation to data security, especially among patients and their clinical providers, is critical to ensure ethical practices, confidentiality, and trust in the healthcare system. As Clinical accelerators and applications that contain user data are used, it is expedient to have a review and revamp of policies like the Payment Card Industry Data Security Standard (PCI DSS), the Health Insurance Portability and Accountability Act (HIPAA), the Fast Healthcare Interoperability Resources (FHIR), all aimed to ensure data protection and security in healthcare. FHIR caters for healthcare data interoperability, FHIR caters to healthcare data interoperability, as data is being shared across different systems from customers to health insurance and care providers. The astronomical cost of implementation has deterred players in the space from ensuring compliance, leading to susceptibility to data exfiltration and data loss on the security accuracy of protected health information (PHI). Though HIPAA hones in on the security accuracy of protected health information (PHI) and PCI DSS on the security of payment card data, they intersect with the shared goal of protecting sensitive information in line with industry standards. With advancements in tech and the emergence of new technology, it is necessary to revamp these policies to address the complexity and ambiguity, cost barrier, and ever-increasing threats in cyberspace. Healthcare data in the wrong hands is a recipe for disaster, and we must enhance its protection and security to protect the mental health of the current and future generations.

Keywords: cloud security, healthcare, cybersecurity, policy and standard

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591 Defence Industry in the Political Economy of State and Business Relations

Authors: Hatice Idil Gorgen

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Turkey has been investing in its national defence industrial base since the 1980s. State’s role in defence industry showed differences in Turkey. Parallel with this, ruling group’s attitude toward companies in defence sector varied. These changes in policies and behaviors of the state have occurred throughout such milestones as political and economic turmoil in domestic and international level. Hence, it is argued that state’s role, relations with private companies in defense sector and its policies towards the defense industry has shown differences due to the international system, political institutions, ideas and political coalitions in Turkey since the 1980s. Therefore, in order to see changes in the role of the state in defence sector, this paper aims to indicate first, history of state’s role in production and defence industry in the post-1980s era. Secondly, to comprehend the changes in the state’s role in defence industry, Stephan Haggard’s sources of policy change will be provided in the theoretical ground. Thirdly, state cooperated, and joint venture defence firms, state’s actions toward them will be observed. The remaining part will explore the underlying reasons for the changes in the role of the state in defence industry, and it implicitly or explicitly impacts on state business relations. Major findings illustrate that targeted idea of self-sufficient or autarky Turkey to attract domestic audience and to raise the prestige through defence system; ruling elites can regard defence industry and involved business groups as a mean for their ends. State dominant value, sensitive perception which has been ever since Ottoman Empire, prioritizes business groups in defence industry compared to others and push the ruling elites to pursue hard power in defence sectors. Through the globally structural transformation in defence industry, integration of Turkey to liberal bloc deepened and widened interdependence among states. Although it is a qualitative study, it involves the numerated data and descriptive statistics. Data will be collected by searching secondary sources from the literature, examining official documents of ministry of defence, and other appropriate ministries.

Keywords: defense industry, state and business relations, public private relations, arm industry

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590 Investigation of External Pressure Coefficients on Large Antenna Parabolic Reflector Using Computational Fluid Dynamics

Authors: Varun K, Pramod B. Balareddy

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Estimation of wind forces plays a significant role in the in the design of large antenna parabolic reflectors. Reflector surface accuracies are very sensitive to the gain of the antenna system at higher frequencies. Hence accurate estimation of wind forces becomes important, which is primary input for design and analysis of the reflector system. In the present work, numerical simulation of wind flow using Computational Fluid Dynamics (CFD) software is used to investigate the external pressure coefficients. An extensive comparative study has been made between the CFD results and the published wind tunnel data for different wind angle of attacks (α) acting over concave to convex surfaces respectively. Flow simulations using CFD are carried out to estimate the coefficients of Drag, Lift and Moment for the parabolic reflector. Coefficients of pressures (Cp) over the front and the rear face of the reflector are extracted over surface of the reflector to study the net pressure variations. These resultant pressure variations are compared with the published wind tunnel data for different angle of attacks. It was observed from the CFD simulations, both convex and concave face of reflector system experience a band of pressure variations for the positive and negative angle of attacks respectively. In the published wind tunnel data, Pressure variations over convex surfaces are assumed to be uniform and vice versa. Chordwise and spanwise pressure variations were calculated and compared with the published experimental data. In the present work, it was observed that the maximum pressure coefficients for α ranging from +30° to -90° and α=+90° was lower. For α ranging from +45° to +75°, maximum pressure coefficients were higher as compared to wind tunnel data. This variation is due to non-uniform pressure distribution observed over front and back faces of reflector. Variations in Cd, Cl and Cm over α=+90° to α=-90° was in close resemblance with the experimental data.

Keywords: angle of attack, drag coefficient, lift coefficient, pressure coefficient

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589 Hypertension and Obesity: A Cross-National Comparison of BMI and Waist-Height Ratio

Authors: Adam M. Yates, Julie E. Byles

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Hypertension has been identified as a prominent co-morbidity of obesity. To improve clinical intervention of hypertension, it is critical to identify metrics that most accurately reflect risk for increased morbidity. Two of the most relevant and accurate measures for increased risk of hypertension due to excess adipose tissue are Body Mass Index (BMI) and Waist-Height Ratio (WHtR). Previous research has examined these measures in cross-national and cross-ethnic studies, but has most often relied on secondary means such as meta-analysis to identify and evaluate the efficacy of individual body mass measures. In this study, we instead use cross-sectional analysis to assess the cross-ethnic discriminative power of BMI and WHtR to predict risk of hypertension. Using the WHO SAGE survey, which collected anthropometric and biometric data from respondents in six middle-income countries (China, Ghana, India, Mexico, Russia, South Africa), we implement logistic regression to examine the discriminative power of measured BMI and WHtR with a known population of hypertensive and non-hypertensive respondents. We control for gender and age to identify whether optimum cut-off points that are adequately sensitive as tests for risk of hypertension may be different between groups. We report results for OR, RR, and ROC curves for each of the six SAGE countries. As seen in existing literature, results demonstrate that both WHtR and BMI are significant predictors of hypertension (p < .01). For these six countries, we find that cut-off points for WHtR may be dependent upon gender, age and ethnicity. While an optimum omnibus cut-point for WHtR may be 0.55, results also suggest that the gender and age relationship with WHtR may warrant the development of individual cut-offs to optimize health outcomes. Trends through multiple countries show that the optimum cut-point for WHtR increases with age while the area under the curve (AUROC) decreases for both men and women. Comparison between BMI and WHtR indicate that BMI may remain more robust than WHtR. Implications for public health policy are discussed.

Keywords: hypertension, obesity, Waist-Height ratio, SAGE

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588 Petrology of the Post-Collisional Dolerites, Basalts from the Javakheti Highland, South Georgia

Authors: Bezhan Tutberidze

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The Neogene-Quaternary volcanic rocks of the Javakheti Highland are products of post-collisional continental magmatism and are related to divergent and convergent margins of Eurasian-Afroarabian lithospheric plates. The studied area constitutes an integral part of the volcanic province of Central South Georgia. Three cycles of volcanic activity are identified here: 1. Late Miocene-Early Pliocene, 2. Late Pliocene-Early /Middle/ Pleistocene and 3. Late Pleistocene. An intense basic dolerite magmatic activity occurred within the time span of the Late Pliocene and lasted until at least Late /Middle/ Pleistocene. The age of the volcanogenic and volcanogenic-sedimentary formation was dated by geomorphological, paleomagnetic, paleontological and geochronological methods /1.7-1.9 Ma/. The volcanic area of the Javakheti Highland contains multiple dolerite Plateaus: Akhalkalaki, Gomarethi, Dmanisi, and Tsalka. Petrographic observations of these doleritic rocks reveal fairly constant mineralogical composition: olivine / Fo₈₇.₆₋₈₂.₇ /, plagioclase / Ab₂₂.₈ An₇₅.₉ Or₁.₃; Ab₄₅.₀₋₃₂.₃ An₅₂.₉₋₆₂.₃ Or₂.₁₋₅.₄/. The pyroxene is an augite and may exhibit a visible zoning: / Wo 39.7-43.1 En 43.5-45.2 Fs 16.8-11.7/. Opaque minerals /magnetite, titanomagnetite/ is abundant as inclusions within olivine and pyroxene crystals. The texture of dolerites exhibits intergranular, holocrystalline to ophitic to sub ophitic granular. Dolerites are most common vesicular rocks. Vesicles range in shape from spherical to elongated and in size from 0.5 mm to than 1.5-2 cm and makeup about 20-50 % of the volume. The dolerites have been subjected to considerable alteration. The secondary minerals in the geothermal field are: zeolite, calcite, chlorite, aragonite, clay-like mineral /dominated by smectites/ and iddingsite –like mineral; rare quartz and pumpellyite are present. These vesicles are filled by secondary minerals. In the chemistry, dolerites are the calc-alkalic transition to sub-alkaline with a predominance of Na₂O over K₂O. Chemical analyses indicate that dolerites of all plateaus of the Javakheti Highland have similar geochemical compositions, signifying that they were formed from the same magmatic source by crystallization of olivine basalis magma which less differentiated / ⁸⁷Sr \ ⁸⁶Sr 0.703920-0704195/. There is one argument, which is less convincing, according to which the dolerites/basalts of the Javakheti Highland are considered to be an activity of a mantle plume. Unfortunately, there does not exist reliable evidence to prove this. The petrochemical peculiarities and eruption nature of the dolerites of the Javakheti Plateau point against their plume origin. Nevertheless, it is not excluded that they influence the formation of dolerite producing primary basaltic magma.

Keywords: calc-alkalic, dolerite, Georgia, Javakheti Highland

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587 A Combined Fiber-Optic Surface Plasmon Resonance and Ta2O5: rGO Nanocomposite Synergistic Scheme for Trace Detection of Insecticide Fenitrothion

Authors: Ravi Kant, Banshi D. Gupta

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The unbridled application of insecticides to enhance agricultural yield has become a matter of grave concern to both the environment and the human health and, thus pose a potential threat to sustainable development. Fenitrothion is an extensively used organophosphate insecticide whose residues are reported to be extremely toxic for birds, humans and aquatic life. A sensitive, swift and accurate detection protocol for fenitrothion is, thus, highly demanded. In this work, we report an SPR based fiber optic sensor for the detection of fenitrothion, where a nanocomposite arrangement of Ta2O5 and reduced graphene oxide (rGO) (Ta₂O₅: rGO) decorated on silver coated unclad core region of an optical fiber forms the sensing channel. A nanocomposite arrangement synergistically integrates the properties of involved components and consequently furnishes a conducive framework for sensing applications. The modification of the dielectric function of the sensing layer on exposure to fenitrothion solutions of diverse concentration forms the sensing mechanism. This modification is reflected in terms of the shift in resonance wavelength. Experimental variables such as the concentration of rGO in the nanocomposite configuration, dip time of silver coated fiber optic probe for deposition of sensing layer and influence of pH on the performance of the sensor have been optimized to extract the best performance of the sensor. SPR studies on the optimized sensing probe reveal the high sensitivity, wide operating range and good reproducibility of the fabricated sensor, which unveil the promising utility of Ta₂O₅: rGO nanocomposite framework for developing an efficient detection methodology for fenitrothion. FOSPR approach in cooperation with nanomaterials projects the present work as a beneficial approach for fenitrothion detection by imparting numerous useful advantages such as sensitivity, selectivity, compactness and cost-effectiveness.

Keywords: surface plasmon resonance, optical fiber, sensor, fenitrothion

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586 Distance and Coverage: An Assessment of Location-Allocation Models for Fire Stations in Kuwait City, Kuwait

Authors: Saad M. Algharib

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The major concern of planners when placing fire stations is finding their optimal locations such that the fire companies can reach fire locations within reasonable response time or distance. Planners are also concerned with the numbers of fire stations that are needed to cover all service areas and the fires, as demands, with standard response time or distance. One of the tools for such analysis is location-allocation models. Location-allocation models enable planners to determine the optimal locations of facilities in an area in order to serve regional demands in the most efficient way. The purpose of this study is to examine the geographic distribution of the existing fire stations in Kuwait City. This study utilized location-allocation models within the Geographic Information System (GIS) environment and a number of statistical functions to assess the current locations of fire stations in Kuwait City. Further, this study investigated how well all service areas are covered and how many and where additional fire stations are needed. Four different location-allocation models were compared to find which models cover more demands than the others, given the same number of fire stations. This study tests many ways to combine variables instead of using one variable at a time when applying these models in order to create a new measurement that influences the optimal locations for locating fire stations. This study also tests how location-allocation models are sensitive to different levels of spatial dependency. The results indicate that there are some districts in Kuwait City that are not covered by the existing fire stations. These uncovered districts are clustered together. This study also identifies where to locate the new fire stations. This study provides users of these models a new variable that can assist them to select the best locations for fire stations. The results include information about how the location-allocation models behave in response to different levels of spatial dependency of demands. The results show that these models perform better with clustered demands. From the additional analysis carried out in this study, it can be concluded that these models applied differently at different spatial patterns.

Keywords: geographic information science, GIS, location-allocation models, geography

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585 Prevalence, Antimicrobial Susceptibility Pattern and Associated Risk Factors for Salmonella Species and Escherichia coli from Raw Meat at Butchery Houses in Mekelle, Tigray, Ethiopia

Authors: Haftay Abraha Tadesse, Atsebaha Gebrekidan Kahsay, Mahumd Abdulkader

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Background: Salmonella species and Escherichia coli are important foodborne pathogens affecting humans and animals. They are among the most important causes of infection that are associated with the consumption of contaminated food. This study was aimed to determine the prevalence, antimicrobial susceptibility patterns and associated risk factors for Salmonella species and E. coli in raw meat from butchery houses of Mekelle, Northern Ethiopia. Methodology: A cross-sectional study was conducted from January to September 2019. Socio-demographic data and risk factors were collected using a predesigned questionnaire. Meat samples were collected aseptically from the butchery houses and transported using icebox to Mekelle University, College of Veterinary Sciences for the isolation and identification of Salmonella species and E. coli, Antimicrobial susceptibility patterns were determined using Kirby disc diffusion method. Data obtained were cleaned and entered into Statistical Package for the Social Sciences version 22 and logistic regression models with odds ratio were calculated. P-value < 0.05 was considered as statistically significant. Results: A total of 153 out of 384 (39.8%) of the meat specimens were found to be contaminated. The contamination of Salmonella species and E. coli were 15.6% (n=60) and 20.8%) (n=80), respectively. Mixed contamination (Salmonella species and E. coli) was observed in 13 (3.4 %) of the analyzed. Poor washing hands regularly (AOR = 8.37; 95% CI: 2.75-25.50) and not using gloves during meat handling (AOR=11. 28; 95% CI: (4.69 27.10) were associated with an overall bacterial contamination.About 95.5% of the tested isolates were sensitive to chloramphenicol and norfloxacin while the resistance of amoxyclav_amoxicillin and erythromycin were both isolated bacteria species. The overall multidrug resistance pattern for Salmonella and E. coli were 51.4% (n=19) and 31.8% (14), respectively. Conclusion: Of the 153 (153/384) contaminated raw meat, 60 (15.6%) and 80 (20.8%) were contaminated by Salmonella species and E. coli, respectively. Poor hand washing practice and not using glove during meat handling showed significant association with bacterial contamination. Multidrug-resistant showed in Salmonella species and E. coli were 19 (51.4%) and 14 (31.8%), respectively.

Keywords: antimicrobial susceptibility test, butchery houses, e. coli, salmonella species

Procedia PDF Downloads 54
584 Enhancing Chinese Foreign Language Teachers’ Intercultural Competence: An Action Research Study

Authors: Wei Hing Rosenkvist

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In the past few decades, concerns and demands of promoting student intercultural communicative competence in foreign language education have been increasing along with the rapid growth of information technologies and globalization in the 21st century. In Sweden, related concepts such as internationalization, global citizenship, multiculturalism, and intercultural communication, are also keywords that would be found in the written learning objectives of foreign language education at all levels. Being one of the leading higher institutes in distance education in Europe, Dalarna University clearly states that after completion of the teacher education program, students shall understand the needs for integrating internationalization, intercultural and global perspective in teaching and learning in Swedish schools and implement their studies to promote education in an international and global context. Even though many teachers and educators agree with the institutes’ mission and vision about the importance of internationalization and the need to increase student understanding of intercultural and global perspectives, they might find this objective unattainable and restricted due to the nature of the subject and their knowledge of intercultural competence. When conducting a comprehensive Chinese language course for the students who are going to become Chinese foreign language teachers, the researcher found that all the learning objectives are linguistic oriented while grammatical components dominate the entire course. Apparently, there is a gap between the learning objectives of the course and the DU’s mission of fostering an international learner with intercultural and globalized perspectives. How to include this macro-learning objective in a foreign language course is a great challenge to the educator. Although scholars from different academic domains have provided different theoretical frameworks and approaches for developing student intercultural competence, research that focuses on the didactic perspectives of developing student intercultural competence in teaching Chinese as a foreign language education (CFL) is limited, and practical examples are rare. This challenge has motivated the researcher to conduct an action research study that aims at integrating DU’s macro-learning objective in a current CFL course through different didactic practices to develop the student's intercultural competence. This research study aims to, firstly, illustrate the cross-cultural knowledge integrated into the present Chinese language course for developing intercultural competence. Secondly, it investigates different didactic means that can be utilized to deliver cross-cultural knowledge to student teachers in the present course without generating dramatic disturbance of the syllabus. Thirdly, it examines the effectiveness of these didactic means in enhancing student-teacher intercultural competence regarding the need for integrating and implementing internationalization, intercultural and global perspectives in teaching and learning in Swedish schools. Last but not least, it intends to serve as a practical example for developing the student teachers’ intercultural competence in foreign language education in DU and fill in the research gap of this academic domain worldwide.

Keywords: action research, intercultural competence, Chinese as a foreign language education, teacher education

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583 Human-Automation Interaction in Law: Mapping Legal Decisions and Judgments, Cognitive Processes, and Automation Levels

Authors: Dovile Petkeviciute-Barysiene

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Legal technologies not only create new ways for accessing and providing legal services but also transform the role of legal practitioners. Both lawyers and users of legal services expect automated solutions to outperform people with objectivity and impartiality. Although fairness of the automated decisions is crucial, research on assessing various characteristics of automated processes related to the perceived fairness has only begun. One of the major obstacles to this research is the lack of comprehensive understanding of what legal actions are automated and could be meaningfully automated, and to what extent. Neither public nor legal practitioners oftentimes cannot envision technological input due to the lack of general without illustrative examples. The aim of this study is to map decision making stages and automation levels which are and/or could be achieved in legal actions related to pre-trial and trial processes. Major legal decisions and judgments are identified during the consultations with legal practitioners. The dual-process model of information processing is used to describe cognitive processes taking place while making legal decisions and judgments during pre-trial and trial action. Some of the existing legal technologies are incorporated into the analysis as well. Several published automation level taxonomies are considered because none of them fit well into the legal context, as they were all created for avionics, teleoperation, unmanned aerial vehicles, etc. From the information processing perspective, analysis of the legal decisions and judgments expose situations that are most sensitive to cognitive bias, among others, also help to identify areas that would benefit from the automation the most. Automation level analysis, in turn, provides a systematic approach to interaction and cooperation between humans and algorithms. Moreover, an integrated map of legal decisions and judgments, information processing characteristics, and automation levels all together provide some groundwork for the research of legal technology perceived fairness and acceptance. Acknowledgment: This project has received funding from European Social Fund (project No 09.3.3-LMT-K-712-19-0116) under grant agreement with the Research Council of Lithuania (LMTLT).

Keywords: automation levels, information processing, legal judgment and decision making, legal technology

Procedia PDF Downloads 144