Search results for: Vijaykumar Sinha
22 A Computational Fluid Dynamics Simulation of Single Rod Bundles with 54 Fuel Rods without Spacers
Authors: S. K. Verma, S. L. Sinha, D. K. Chandraker
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The Advanced Heavy Water Reactor (AHWR) is a vertical pressure tube type, heavy water moderated and boiling light water cooled natural circulation based reactor. The fuel bundle of AHWR contains 54 fuel rods arranged in three concentric rings of 12, 18 and 24 fuel rods. This fuel bundle is divided into a number of imaginary interacting flow passage called subchannels. Single phase flow condition exists in reactor rod bundle during startup condition and up to certain length of rod bundle when it is operating at full power. Prediction of the thermal margin of the reactor during startup condition has necessitated the determination of the turbulent mixing rate of coolant amongst these subchannels. Thus, it is vital to evaluate turbulent mixing between subchannels of AHWR rod bundle. With the remarkable progress in the computer processing power, the computational fluid dynamics (CFD) methodology can be useful for investigating the thermal–hydraulic characteristics phenomena in the nuclear fuel assembly. The present report covers the results of simulation of pressure drop, velocity variation and turbulence intensity on single rod bundle with 54 rods in circular arrays. In this investigation, 54-rod assemblies are simulated with ANSYS Fluent 15 using steady simulations with an ANSYS Workbench meshing. The simulations have been carried out with water for Reynolds number 9861.83. The rod bundle has a mean flow area of 4853.0584 mm2 in the bare region with the hydraulic diameter of 8.105 mm. In present investigation, a benchmark k-ε model has been used as a turbulence model and the symmetry condition is set as boundary conditions. Simulation are carried out to determine the turbulent mixing rate in the simulated subchannels of the reactor. The size of rod and the pitch in the test has been same as that of actual rod bundle in the prototype. Water has been used as the working fluid and the turbulent mixing tests have been carried out at atmospheric condition without heat addition. The mean velocity in the subchannel has been varied from 0-1.2 m/s. The flow conditions are found to be closer to the actual reactor condition.Keywords: AHWR, CFD, single-phase turbulent mixing rate, thermal–hydraulic
Procedia PDF Downloads 32021 Treatment of High Concentration Cutting Fluid Wastewater by Ceramic Membrane Bioreactor
Authors: Kai-Shiang Chang, Shiao-Shing Chen, Saikat Sinha Ray, Hung-Te Hsu
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In recent years, membrane bioreactors (MBR) have been widely utilized as it can effectively replace conventional activated sludge process (CAS). Membrane bioreactor (MBR) is found to be more effective technology compared to other conventional activated sludge process and advanced membrane separation technique. Additionally, as far as the MBR is concerned, it is having excellent control of sludge retention time (SRT) and hydraulic retention time (HRT) and conducive to the retention of high concentration of sludge biomass. The membrane bioreactor (MBR) can effectively reduce footprint in terms of area and omit the secondary processing procedures in the conventional activated sludge process (CAS). Currently, as per the membrane technology, the ceramic membrane is found to have highly strong anti-acid-base properties, and it is more suitable than polymeric membrane while using for backwash and chemical cleaning. This study is based upon the treatment of Cutting Fluid wastewater, as the Cutting Fluid is widely used in the cutting equipment. However, the Cutting Fluid wastewater is very difficult to treat. In this study, the ceramic membrane was used and combine with of MBR system to treat the Cutting Fluid wastewater. In this present study, different kind of chemical coagulants have been utilized for pretreatment purpose in order to get the supernatant and simultaneously this wastewater (supernatant) was treated by MBR process. Nevertheless, ceramic membrane has three advantages such as high mechanical strength, drug resistance and reuse. During the experiment, the backwash technique was used for every interval of 10 minutes in order to avoid fouling of the membrane. In this study, during pretreatment the Chemical Oxygen Demand (COD) removal efficiency was found to be 71-86% and oil removal efficiency was analyzed to be 83-92%. This pretreatment study suggests that it is quiet effective methodology to reduce COD and oil concentration. Finally, In the MBR system when the HRT is more than 7.5 hour, the COD removal efficiency was found to be 87-93% and could achieve 100% oil removal efficiency. Coagulation test series were seen in Refs coagulants for the treatment of wastewater containing cutting oil with better oil and COD removal efficiency. The results also showed that the oil removal efficiency in the MBR system could reduce the oil content to less than 1 mg / L when the oil quality was 126 mg / L. Therefore, in this paper, the performance of membrane bioreactor by utilizing ceramic membrane has been demonstrated for treatment of Cutting Fluid wastewater.Keywords: membrane bioreactor, cutting fluid, oil, chemical oxygen demand
Procedia PDF Downloads 31420 Therapeutic Role of T Subpopulations Cells (CD4, CD8 and Treg (CD25 and FOXP3+ Cells) of UC MSC Isolated from Three Different Methods in Various Disease
Authors: Kumari Rekha, Mathur K Dhananjay, Maheshwari Deepanshu, Nautiyal Nidhi, Shubham Smriti, Laal Deepika, Sinha Swati, Kumar Anupam, Biswas Subhrajit, Shiv Kumar Sarin
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Background: Mesenchymal stem cells are multipotent stem cells derived from mesoderm and are used for therapeutic purposes because of their self-renewal, homing capacity, Immunomodulatory capability, low immunogenicity and mitochondrial transfer signaling. MSCs have the ability to regulate the mechanism of both innate as well as adaptive immune responses through the modulation of cellular response and the secretion of inflammatory mediators. Different sources of MSC are UC MSC, BM MSC, Dental Pulp, and Adipose MSC. The most frequent source used is umbilical cord tissue due to its being easily available and free of limitations of collection procedures from respective hospitals. The immunosuppressive role of MSCs is particularly interesting for clinical use since it confers resistance to rejection by the host immune response. Methodology: In this study, T helper cells (TH4), Cytotoxic T cells (CD-8), immunoregulatory cells (CD25 +FOXP3+) are compared from isolated MSC from three different methods, UC Dissociation Kit (Miltenyi), Explant Culture and Collagenase Type-IV. To check the immunomodulatory property, these MSCs were seeded with PBMC(Coculture) in CD3 coated 24 well plates. Cd28 antibody was added in coculture for six days. The coculture was analyzed in FACS Verse flow cytometry. Results: From flow cytometry analysis of coculture, it found that All over T helper cells (CD4+) number p<0.0264 increases in (All Enzymes) MSC rather than explant MSC(p>0.0895) as compared to Collagenase(p>0.7889) in a coculture of Activated T cell and Mesenchymal Stem Cell. Similar T reg cells (CD25+, FOXP3+) expression p<0.0234increases in All Enzymes), decreases in Explant and Collagenase. Experiments have shown that MSCs can also directly prevent the cytotoxic activity of CD8 lymphocytes mainly by blocking their proliferation rather than by inhibiting the cytotoxic effect. And promoting the t-reg cells, which helps in the mediation of immune response in various diseases. Conclusion: MSC suppress Cytotoxic CD8 T cell and Enhance immunoregulatory T reg (CD4+, CD25+, FOXP3+) Cell expression. Thus, MSC maintains a proper balance(ratio) between CD4 T cells and Cytotoxic CD8 T cells.Keywords: MSC, disease, T cell, T regulatory
Procedia PDF Downloads 11319 CFD Simulation of Spacer Effect on Turbulent Mixing Phenomena in Sub Channels of Boiling Nuclear Assemblies
Authors: Shashi Kant Verma, S. L. Sinha, D. K. Chandraker
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Numerical simulations of selected subchannel tracer (Potassium Nitrate) based experiments have been performed to study the capabilities of state-of-the-art of Computational Fluid Dynamics (CFD) codes. The Computational Fluid Dynamics (CFD) methodology can be useful for investigating the spacer effect on turbulent mixing to predict turbulent flow behavior such as Dimensionless mixing scalar distributions, radial velocity and vortices in the nuclear fuel assembly. A Gibson and Launder (GL) Reynolds stress model (RSM) has been selected as the primary turbulence model to be applied for the simulation case as it has been previously found reasonably accurate to predict flows inside rod bundles. As a comparison, the case is also simulated using a standard k-ε turbulence model that is widely used in industry. Despite being an isotropic turbulence model, it has also been used in the modeling of flow in rod bundles and to produce lateral velocities after thorough mixing of coolant fairly. Both these models have been solved numerically to find out fully developed isothermal turbulent flow in a 30º segment of a 54-rod bundle. Numerical simulation has been carried out for the study of natural mixing of a Tracer (Passive scalar) to characterize the growth of turbulent diffusion in an injected sub-channel and, afterwards on, cross-mixing between adjacent sub-channels. The mixing with water has been numerically studied by means of steady state CFD simulations with the commercial code STAR-CCM+. Flow enters into the computational domain through the mass inflow at the three subchannel faces. Turbulence intensity and hydraulic diameter of 1% and 5.9 mm respectively were used for the inlet. A passive scalar (Potassium nitrate) is injected through the mass fraction of 5.536 PPM at subchannel 2 (Upstream of the mixing section). Flow exited the domain through the pressure outlet boundary (0 Pa), and the reference pressure was 1 atm. Simulation results have been extracted at different locations of the mixing zone and downstream zone. The local mass fraction shows uniform mixing. The effect of the applied turbulence model is nearly negligible just before the outlet plane because the distributions look like almost identical and the flow is fully developed. On the other hand, quantitatively the dimensionless mixing scalar distributions change noticeably, which is visible in the different scale of the colour bars.Keywords: single-phase flow, turbulent mixing, tracer, sub channel analysis
Procedia PDF Downloads 20718 Functional Performance of Unpaved Roads Reinforced with Treated Coir Geotextiles
Authors: Priya Jaswal, Vivek, S. K. Sinha
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One of the most important and complicated factors influencing the functional performance of unpaved roads is traffic loading. The complexity of traffic loading is caused by the variable magnitude and frequency of load, which causes unpaved roads to fail prematurely. Unpaved roads are low-volume roads, and as peri-urbanization increases, unpaved roads act as a means to boost the rural economy. This has also increased traffic on unpaved roads, intensifying the issue of settlement, rutting, and fatigue failure. This is a major concern for unpaved roads built on poor subgrade soil, as excessive rutting caused by heavy loads can cause driver discomfort, vehicle damage, and an increase in maintenance costs. Some researchers discovered that when a consistent static load is exerted as opposed to a rapidly changing load, the rate of deformation of unpaved roads increases. Previously, some of the most common methods for overcoming the problem of rutting and fatigue failure included chemical stabilisation, fibre reinforcement, and so on. However, due to their high cost, engineers' attention has shifted to geotextiles which are used as reinforcement in unpaved roads. Geotextiles perform the function of filtration, lateral confinement of base material, vertical restraint of subgrade soil, and the tension membrane effect. The use of geotextiles in unpaved roads increases the strength of unpaved roads and is an economically viable method because it reduces the required aggregate thickness, which would need less earthwork, and is thus recommended for unpaved road applications. The majority of geotextiles used previously were polymeric, but with a growing awareness of sustainable development to preserve the environment, researchers' focus has shifted to natural fibres. Coir is one such natural fibre that possesses the advantage of having a higher tensile strength than other bast fibres, being eco-friendly, low in cost, and biodegradable. However, various researchers have discovered that the surface of coir fibre is covered with various impurities, voids, and cracks, which act as a plane of weakness and limit the potential application of coir geotextiles. To overcome this limitation, chemical surface modification of coir geotextiles is widely accepted by researchers because it improves the mechanical properties of coir geotextiles. The current paper reviews the effect of using treated coir geotextiles as reinforcement on the load-deformation behaviour of a two-layered unpaved road model.Keywords: coir, geotextile, treated, unpaved
Procedia PDF Downloads 9317 Structural and Binding Studies of Peptidyl-tRNA Hydrolase from Pseudomonas aeruginosa Provide a Platform for the Structure Based Inhibitor Design against Peptidyl-tRNA Hydrolase
Authors: Sujata Sharma, Avinash Singh, Lovely Gautam, Pradeep Sharma, Mau Sinha, Asha Bhushan, Punit Kaur, Tej P. Singh
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Peptidyl-tRNA hydrolase (Pth) Pth is an essential bacterial enzyme that catalyzes the release of free tRNA and peptide moeities from peptidyl tRNAs during stalling of protein synthesis. In order to design inhibitors of Pth from Pseudomonas aeruginosa (PaPth), we have determined the structures of PaPth in its native state and in the bound states with two compounds, amino acylate-tRNA analogue (AAtA) and 5-azacytidine (AZAC). The peptidyl-tRNA hydrolase gene from Pseudomonas aeruginosa was amplified by Phusion High-Fidelity DNA Polymerase using forward and reverse primers, respectively. The E. coliBL21 (λDE3) strain was used for expression of the recombinant peptidyl-tRNA hydrolase from Pseudomonas aeruginosa. The protein was purified using a Ni-NTA superflow column. The crystallization experiments were carried out using hanging drop vapour diffusion method. The crystals diffracted to 1.50 Å resolution. The data were processed using HKL-2000. The polypeptide chain of PaPth consists of 194 amino acid residues from Met1 to Ala194. The centrally located β-structure is surrounded by α-helices from all sides except the side that has entrance to the substrate binding site. The structures of the complexes of PaPth with AAtA and AZAC showed the ligands bound to PaPth in the substrate binding cleft and interacted with protein atoms extensively. The residues that formed intermolecular hydrogen bonds with the atoms of AAtA included Asn12, His22, Asn70, Gly113, Asn116, Ser148, and Glu161 of the symmetry related molecule. The amino acids that were involved in hydrogen bonded interactions in case of AZAC included, His22, Gly113, Asn116, and Ser148. As indicated by fittings of two ligands and the number of interactions made by them with protein atoms, AAtA appears to be a more compatible with the structure of the substrate binding cleft. However, there is a further scope to achieve a better stacking than that of O-tyrosyl moiety because it is not still ideally stacked. These observations about the interactions between the protein and ligands have provided the information about the mode of binding of ligands, nature and number of interactions. This information may be useful for the design of tight inhibitors of Pth enzymes.Keywords: peptidyl tRNA hydrolase, Acinetobacter baumannii, Pth enzymes, O-tyrosyl
Procedia PDF Downloads 43016 Perceived Competence toward Helping an Accident Victim in Pre-Hospital Setting among Medical Graduates: A Cross Sectional Study from Jodhpur, Rajasthan
Authors: Neeti Rustagi, Naveen Dutt, Arvind Sinha, Mahaveer S. Rhodha, Pankaja R. Raghav
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Background: Pre-hospital trauma care services are in developing stage in fast-urbanizing cities of India including Jodhpur. Training of health professionals in providing necessary pre-hospital trauma care is an essential step in decreasing accident related morbidity and mortality. The current study explores the response of a medical graduate toward helping an accident victim in a pre-hospital setting before patient can be transferred to definitive trauma facility. Methodology: This study examines the perceived competence in predicting response to an accident victim by medical graduates in Jodhpur, Rajasthan. Participants completed measures of attitude, normative influence and perceived behavior control toward providing pre-hospital care to an accident victim. Likert scale was used to measure the participant responses. Preliminary and descriptive analysis were used using SPSS 21.0. Internal consistency of the responses received was measured using Cronbach’s alpha. Results: Almost all medical graduates agreed that road accidents are common in their area (male: 92%; female: 78%). More male medical graduates (28%) reported helping an accident victim as compared to female physicians (9%) in the previous three months. Majority of study participants (96%) reported that providing immediate care to an accident victim is essential to save the life of an individual. Experience of helping an accident victim was considered unpleasant by the majority of female participants (70%) as compared to male participants (36%). A large number of participants believed that their friends (80%) and colleagues (96%) would appreciate them helping an accident victim in a pre-hospital setting. A large number of participants also believed that they possess the necessary skills and competencies (80%) towards helping a roadside accident victim in the pre-hospital care environment. Perceived competence of helping a roadside accident victim until they are transferred to a health facility was reported by less than half of the participants (male: 56%; female: 43%). Conclusion: Medical graduates have necessary attitude, competencies, and intention of helping a roadside accident victim. The societal response towards helping a road side accident victim is also supportive. In spite of positive determinants, a large proportion of medical graduates have perceived lack of competence in helping a roadside accident victim. This is essential to explore further as providing pre-hospital care to a roadside accident victim is an essential step in establishing the continuum of care to an accident victim especially in countries where pre-hospital services are in developing phase.Keywords: prehospital care, perceived behavior, perceived competence, medical graduates
Procedia PDF Downloads 13015 Amniotic Fluid Stem Cells Ameliorate Cisplatin-Induced Acute Renal Failure through Autophagy Induction and Inhibition of Apoptosis
Authors: Soniya Nityanand, Ekta Minocha, Manali Jain, Rohit Anthony Sinha, Chandra Prakash Chaturvedi
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Amniotic fluid stem cells (AFSC) have been shown to contribute towards the amelioration of Acute Renal Failure (ARF), but the mechanisms underlying the renoprotective effect are largely unknown. Therefore, the main goal of the current study was to evaluate the therapeutic efficacy of AFSC in a cisplatin-induced rat model of ARF and to investigate the underlying mechanisms responsible for its renoprotective effect. To study the therapeutic efficacy of AFSC, ARF was induced in Wistar rats by an intra-peritoneal injection of cisplatin, and five days after administration, the rats were randomized into two groups and injected with either AFSC or normal saline intravenously. On day 8 and 12 after cisplatin injection, i.e., day 3 and day7 post-therapy respectively, the blood biochemical parameters, histopathological changes, apoptosis and expression of pro-apoptotic, anti-apoptotic and autophagy-related proteins in renal tissues were studied in both groups of rats. Administration of AFSC in ARF rats resulted in improvement of renal function and attenuation of renal damage as reflected by significant decrease in blood urea nitrogen, serum creatinine levels, tubular cell apoptosis as assessed by Bax/Bcl2 ratio, and expression of the pro-apoptotic proteins viz. PUMA, Bax, cleaved caspase-3 and cleaved caspase-9 as compared to saline-treated group. Furthermore, in the AFSC-treated group as compared to saline-treated group, there was a significant increase in the activation of autophagy as evident by increased expression of LC3-II, ATG5, ATG7, Beclin1 and phospho-AMPK levels with a concomitant decrease in phospho-p70S6K and p62 expression levels. To further confirm whether the protective effects of AFSC on cisplatin-induced apoptosis were dependent on autophagy, chloroquine, an autophagy inhibitor was administered by the intra-peritoneal route. Chloroquine administration led to significant reduction in the anti-apoptotic effects of the AFSC therapy and further deterioration in the renal structure and function caused by cisplatin. Collectively, our results put forth that AFSC ameliorates cisplatin-induced ARF through induction of autophagy and inhibition of apoptosis. Furthermore, the protective effects of AFSC were blunted by chloroquine, highlighting that activation of autophagy is an important mechanism of action for the protective role of AFSC in cisplatin-induced renal injury.Keywords: amniotic fluid stem cells, acute renal failure, autophagy, cisplatin
Procedia PDF Downloads 10414 Integration of EEG and Motion Tracking Sensors for Objective Measure of Attention-Deficit Hyperactivity Disorder in Pre-Schoolers
Authors: Neha Bhattacharyya, Soumendra Singh, Amrita Banerjee, Ria Ghosh, Oindrila Sinha, Nairit Das, Rajkumar Gayen, Somya Subhra Pal, Sahely Ganguly, Tanmoy Dasgupta, Tanusree Dasgupta, Pulak Mondal, Aniruddha Adhikari, Sharmila Sarkar, Debasish Bhattacharyya, Asim Kumar Mallick, Om Prakash Singh, Samir Kumar Pal
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Background: We aim to develop an integrated device comprised of single-probe EEG and CCD-based motion sensors for a more objective measure of Attention-deficit Hyperactivity Disorder (ADHD). While the integrated device (MAHD) relies on the EEG signal (spectral density of beta wave) for the assessment of attention during a given structured task (painting three segments of a circle using three different colors, namely red, green and blue), the CCD sensor depicts movement pattern of the subjects engaged in a continuous performance task (CPT). A statistical analysis of the attention and movement patterns was performed, and the accuracy of the completed tasks was analysed using indigenously developed software. The device with the embedded software, called MAHD, is intended to improve certainty with criterion E (i.e. whether symptoms are better explained by another condition). Methods: We have used the EEG signal from a single-channel dry sensor placed on the frontal lobe of the head of the subjects (3-5 years old pre-schoolers). During the painting of three segments of a circle using three distinct colors (red, green, and blue), absolute power for delta and beta EEG waves from the subjects are found to be correlated with relaxation and attention/cognitive load conditions. While the relaxation condition of the subject hints at hyperactivity, a more direct CCD-based motion sensor is used to track the physical movement of the subject engaged in a continuous performance task (CPT) i.e., separation of the various colored balls from one table to another. We have used our indigenously developed software for the statistical analysis to derive a scale for the objective assessment of ADHD. We have also compared our scale with clinical ADHD evaluation. Results: In a limited clinical trial with preliminary statistical analysis, we have found a significant correlation between the objective assessment of the ADHD subjects with that of the clinician’s conventional evaluation. Conclusion: MAHD, the integrated device, is supposed to be an auxiliary tool to improve the accuracy of ADHD diagnosis by supporting greater criterion E certainty.Keywords: ADHD, CPT, EEG signal, motion sensor, psychometric test
Procedia PDF Downloads 9813 Development and Characterization of Topical 5-Fluorouracil Solid Lipid Nanoparticles for the Effective Treatment of Non-Melanoma Skin Cancer
Authors: Sudhir Kumar, V. R. Sinha
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Background: The topical and systemic toxicity associated with present nonmelanoma skin cancer (NMSC) treatment therapy using 5-Fluorouracil (5-FU) make it necessary to develop a novel delivery system having lesser toxicity and better control over drug release. Solid lipid nanoparticles offer many advantages like: controlled and localized release of entrapped actives, nontoxicity, and better tolerance. Aim:-To investigate safety and efficacy of 5-FU loaded solid lipid nanoparticles as a topical delivery system for the treatment of nonmelanoma skin cancer. Method: Topical solid lipid nanoparticles of 5-FU were prepared using Compritol 888 ATO (Glyceryl behenate) as lipid component and pluronic F68 (Poloxamer 188), Tween 80 (Polysorbate 80), Tyloxapol (4-(1,1,3,3-Tetramethylbutyl) phenol polymer with formaldehyde and oxirane) as surfactants. The SLNs were prepared with emulsification method. Different formulation parameters viz. type and ratio of surfactant, ratio of lipid and ratio of surfactant:lipid were investigated on particle size and drug entrapment efficiency. Results: Characterization of SLNs like–Transmission Electron Microscopy (TEM), Differential Scannig calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), Particle size determination, Polydispersity index, Entrapment efficiency, Drug loading, ex vivo skin permeation and skin retention studies, skin irritation and histopathology studies were performed. TEM results showed that shape of SLNs was spherical with size range 200-500nm. Higher encapsulation efficiency was obtained for batches having higher concentration of surfactant and lipid. It was found maximum 64.3% for SLN-6 batch with size of 400.1±9.22 nm and PDI 0.221±0.031. Optimized SLN batches and marketed 5-FU cream were compared for flux across rat skin and skin drug retention. The lesser flux and higher skin retention was obtained for SLN formulation in comparison to topical 5-FU cream, which ensures less systemic toxicity and better control of drug release across skin. Chronic skin irritation studies lacks serious erythema or inflammation and histopathology studies showed no significant change in physiology of epidermal layers of rat skin. So, these studies suggest that the optimized SLN formulation is efficient then marketed cream and safer for long term NMSC treatment regimens. Conclusion: Topical and systemic toxicity associated with long-term use of 5-FU, in the treatment of NMSC, can be minimized with its controlled release with significant drug retention with minimal flux across skin. The study may provide a better alternate for effective NMSC treatment.Keywords: 5-FU, topical formulation, solid lipid nanoparticles, non melanoma skin cancer
Procedia PDF Downloads 51612 Application of a Submerged Anaerobic Osmotic Membrane Bioreactor Hybrid System for High-Strength Wastewater Treatment and Phosphorus Recovery
Authors: Ming-Yeh Lu, Shiao-Shing Chen, Saikat Sinha Ray, Hung-Te Hsu
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Recently, anaerobic membrane bioreactors (AnMBRs) has been widely utilized, which combines anaerobic biological treatment process and membrane filtration, that can be present an attractive option for wastewater treatment and water reuse. Conventional AnMBR is having several advantages, such as improving effluent quality, compact space usage, lower sludge yield, without aeration and production of energy. However, the removal of nitrogen and phosphorus in the AnMBR permeate was negligible which become the biggest disadvantage. In recent years, forward osmosis (FO) is an emerging technology that utilizes osmotic pressure as driving force to extract clean water without additional external pressure. The pore size of FO membrane is kindly mentioned the pore size, so nitrogen or phosphorus could effectively improve removal of nitrogen or phosphorus. Anaerobic bioreactor with FO membrane (AnOMBR) can retain the concentrate organic matters and nutrients. However, phosphorus is a non-renewable resource. Due to the high rejection property of FO membrane, the high amount of phosphorus could be recovered from the combination of AnMBR and FO. In this study, development of novel submerged anaerobic osmotic membrane bioreactor integrated with periodic microfiltration (MF) extraction for simultaneous phosphorus and clean water recovery from wastewater was evaluated. A laboratory-scale AnOMBR utilizes cellulose triacetate (CTA) membranes with effective membrane area of 130 cm² was fully submerged into a 5.5 L bioreactor at 30-35℃. Active layer-facing feed stream orientation was utilized, for minimizing fouling and scaling. Additionally, a peristaltic pump was used to circulate draw solution (DS) at a cross flow velocity of 0.7 cm/s. Magnesium sulphate (MgSO₄) solution was used as DS. Microfiltration membrane periodically extracted about 1 L solution when the TDS reaches to 5 g/L to recover phosphorus and simultaneous control the salt accumulation in the bioreactor. During experiment progressed, the average water flux was achieved around 1.6 LMH. The AnOMBR process show greater than 95% removal of soluble chemical oxygen demand (sCOD), nearly 100% of total phosphorous whereas only partial removal of ammonia, and finally average methane production of 0.22 L/g sCOD was obtained. Therefore, AnOMBR system periodically utilizes MF membrane extracted for phosphorus recovery with simultaneous pH adjustment. The overall performance demonstrates that a novel submerged AnOMBR system is having potential for simultaneous wastewater treatment and resource recovery from wastewater, and hence, the new concept of this system can be used to replace for conventional AnMBR in the future.Keywords: anaerobic treatment, forward osmosis, phosphorus recovery, membrane bioreactor
Procedia PDF Downloads 27011 Deep Convolutional Neural Network for Detection of Microaneurysms in Retinal Fundus Images at Early Stage
Authors: Goutam Kumar Ghorai, Sandip Sadhukhan, Arpita Sarkar, Debprasad Sinha, G. Sarkar, Ashis K. Dhara
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Diabetes mellitus is one of the most common chronic diseases in all countries and continues to increase in numbers significantly. Diabetic retinopathy (DR) is damage to the retina that occurs with long-term diabetes. DR is a major cause of blindness in the Indian population. Therefore, its early diagnosis is of utmost importance towards preventing progression towards imminent irreversible loss of vision, particularly in the huge population across rural India. The barriers to eye examination of all diabetic patients are socioeconomic factors, lack of referrals, poor access to the healthcare system, lack of knowledge, insufficient number of ophthalmologists, and lack of networking between physicians, diabetologists and ophthalmologists. A few diabetic patients often visit a healthcare facility for their general checkup, but their eye condition remains largely undetected until the patient is symptomatic. This work aims to focus on the design and development of a fully automated intelligent decision system for screening retinal fundus images towards detection of the pathophysiology caused by microaneurysm in the early stage of the diseases. Automated detection of microaneurysm is a challenging problem due to the variation in color and the variation introduced by the field of view, inhomogeneous illumination, and pathological abnormalities. We have developed aconvolutional neural network for efficient detection of microaneurysm. A loss function is also developed to handle severe class imbalance due to very small size of microaneurysms compared to background. The network is able to locate the salient region containing microaneurysms in case of noisy images captured by non-mydriatic cameras. The ground truth of microaneurysms is created by expert ophthalmologists for MESSIDOR database as well as private database, collected from Indian patients. The network is trained from scratch using the fundus images of MESSIDOR database. The proposed method is evaluated on DIARETDB1 and the private database. The method is successful in detection of microaneurysms for dilated and non-dilated types of fundus images acquired from different medical centres. The proposed algorithm could be used for development of AI based affordable and accessible system, to provide service at grass root-level primary healthcare units spread across the country to cater to the need of the rural people unaware of the severe impact of DR.Keywords: retinal fundus image, deep convolutional neural network, early detection of microaneurysms, screening of diabetic retinopathy
Procedia PDF Downloads 14110 An Assessment of Suitable Alternative Public Transport System in Mid-Sized City of India
Authors: Sanjeev Sinha, Samir Saurav
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The rapid growth of urban areas in India has led to transportation challenges like traffic congestion and an increase in accidents. Despite efforts by state governments and local administrations to improve urban transport, the surge in private vehicles has worsened the situation. Patna, located in Bihar State, is an example of the trend of increasing reliance on private motor vehicles, resulting in vehicular congestion and emissions. The existing transportation infrastructure is inadequate to meet future travel demands, and there has been a notable increase in the share of private vehicles in the city. Additionally, there has been a surge in economic activities in the region, which has increased the demand for improved travel convenience and connectivity. To address these challenges, a study was conducted to assess the most suitable transit mode for the proposed transit corridor outlined in the Comprehensive Mobility Plan (CMP) for Patna. The study covered four stages: developing screening criteria, evaluating parameters for various alternatives, qualitative and quantitative evaluations of alternatives, and implementation options for the most viable alternative. The study suggests that a mass transit system such as a metro rail is necessary to enhance Patna's urban public transport system. The New Metro Policy 2017 outlines specific prerequisites for submitting a Metro Rail Project Proposal to the Ministry of Housing and Urban Affairs (MoHUA), including the preparation of a CMP, the formation of an Urban Metropolitan Transport Authority (UMTA), the creation of an Alternative Analysis Report, the development of a Detailed Project Report, a Multi-Modal Integration Plan, and a Transit-Oriented Development (TOD) Plan. In 2018, the Comprehensive Mobility Plan for Patna was prepared, setting the stage for the subsequent steps in the metro rail project proposal. The results indicated that from the screening and analysis of qualitative parameters for different alternative modes in Patna, it is inferred that the Metro Rail and Monorail score 82.25 and 70.50, respectively, on a scale of 100. Based on the initial analysis and alternative evaluation in the form of quantitative analysis, the Metro Rail System significantly outperformed the Monorail system. The Metro Rail System has a positive Economic Net Present Value (ENPV) at a 14% internal rate of return, while the Monorail has a negative value. In conclusion, the study recommends choosing metro rail over monorail for the proposed transit corridor in Patna. However, the lack of broad-based technical expertise may result in implementation delays and increased costs for monorail.Keywords: comprehensive mobility plan, alternative analysis, mobility corridors, mass transit system
Procedia PDF Downloads 1199 Re-Entrant Direct Hexagonal Phases in a Lyotropic System Induced by Ionic Liquids
Authors: Saheli Mitra, Ramesh Karri, Praveen K. Mylapalli, Arka. B. Dey, Gourav Bhattacharya, Gouriprasanna Roy, Syed M. Kamil, Surajit Dhara, Sunil K. Sinha, Sajal K. Ghosh
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The most well-known structures of lyotropic liquid crystalline systems are the two dimensional hexagonal phase of cylindrical micelles with a positive interfacial curvature and the lamellar phase of flat bilayers with zero interfacial curvature. In aqueous solution of surfactants, the concentration dependent phase transitions have been investigated extensively. However, instead of changing the surfactant concentrations, the local curvature of an aggregate can be altered by tuning the electrostatic interactions among the constituent molecules. Intermediate phases with non-uniform interfacial curvature are still unexplored steps to understand the route of phase transition from hexagonal to lamellar. Understanding such structural evolution in lyotropic liquid crystalline systems is important as it decides the complex rheological behavior of the system, which is one of the main interests of the soft matter industry. Sodium dodecyl sulfate (SDS) is an anionic surfactant and can be considered as a unique system to tune the electrostatics by cationic additives. In present study, imidazolium-based ionic liquids (ILs) with different number of carbon atoms in their single hydrocarbon chain were used as the additive in the aqueous solution of SDS. At a fixed concentration of total non-aqueous components (SDS and IL), the molar ratio of these components was changed, which effectively altered the electrostatic interactions between the SDS molecules. As a result, the local curvature is observed to modify, and correspondingly, the structure of the hexagonal liquid crystalline phases are transformed into other phases. Polarizing optical microscopy of SDS and imidazole-based-IL systems have exhibited different textures of the liquid crystalline phases as a function of increasing concentration of the ILs. The small angle synchrotron x-ray diffraction (SAXD) study has indicated the hexagonal phase of direct cylindrical micelles to transform to a rectangular phase at the presence of short (two hydrocarbons) chain IL. However, the hexagonal phase is transformed to a lamellar phase at the presence of long (ten hydrocarbons) chain IL. Interestingly, at the presence of a medium (four hydrocarbons) chain IL, the hexagonal phase is transformed to another hexagonal phase of direct cylindrical micelles through the lamellar phase. To the best of our knowledge, such a phase sequence has not been reported earlier. Even though the small angle x-ray diffraction study has revealed the lattice parameters of these phases to be similar to each other, their rheological behavior has been distinctly different. These rheological studies have shed lights on how these phases differ in their viscoelastic behavior. Finally, the packing parameters, calculated for these phases based on the geometry of the aggregates, have explained the formation of the self-assembled aggregates.Keywords: lyotropic liquid crystals, polarizing optical microscopy, rheology, surfactants, small angle x-ray diffraction
Procedia PDF Downloads 1388 Tracking Patient Pathway for Assessing Public Health and Financial Burden to Community for Pulmonary Tuberculosis: Pointer from Central India
Authors: Ashish Sinha, Pushpend Agrawal
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Background: Patients with undiagnosed pulmonary TB predominantly act as reservoirs for its transmission through 10-15 secondary infections in the next 1-5 Yrs. Delays in the diagnosis and treatment may worsen the disease with increase the risk of death. Factors responsible for such delays by tracking patient pathways to treatment may help in planning better interventions. The provision of ‘free diagnosis and treatment’ forms the cornerstone of the National Tuberculosis Elimination Programme (NTEP). OOPE is defined as the money spent by the patient during TB care other than public health facilities. Free TB care at all health facilities could reduce out-of-pocket expenses to the minimum possible levels. Material and Methods: This cross-sectional study was conducted among randomly selected 252 TB patients from Nov – Oct 2022 by taking in-depth interviews following informed verbal consent. We documented their journey from initial symptoms until they reached the public health facility, along with their ‘out-of-pocket expenditure’ (OOPE) pertaining to TB care. Results: Total treatment delay was 91±72 days on average (median: 77days, IQR: 45-104 days), while the isolated patient delay was 31±45 days (median: 15 days, IQR: 0 days to 43 days); diagnostic delay; 57±60 days (median: 42days, IQR 14-78 days), treatment delay 19 ± 18 days (median: 15days, IQR: 11-19 days). A patient delay (> 30 days) was significantly associated with ignorance about classic symptoms of pulmonary TB, adoption of self-medication, illiteracy, and middle and lower social class. Diagnostic delay was significantly higher among those who contacted private health facilities, were unaware of signs and symptoms, had >2 consultations, and not getting an appropriate referral for TB care. Most (97%) of the study participants interviewed claimed to have incurred some expenditure.Median total expenses were 6155(IQR: 2625-15175) rupees. More than half 141 (56%) of the study participants had expenses >5000 rupees. Median transport expenses were 525(IQR: 200-1012) rupees; Median consultation expenses were 700(IQR: 200-1600) rupees; Median investigation expenses were 1000(IQR: 0-3025) rupees and the Median medicine expenses were 3350(IQR: 1300-7525).OOPE for consultation, investigation, and medicine was observed to be significantly higher among patients who ignored classical signs& symptoms of TB, repeated visits to private health facilities, and due to self-medication practices. Transport expenses and delays in seeking care at facilities were observed to have an upward trend with OOP Expenses (r =1). Conclusion: Delay in TB care due to low awareness about signs and symptoms of TB and poor seeking care, lack of proper consultation, and appropriate referrals reported by the study subjects indicate the areas which need proper attention by the program managers. Despite a centrally sponsored programme, the financial burden on TB patients is still in the unacceptable range. OOPE could be reduced as low as possible by addressing the responsible factors linked to it.Keywords: patient pathway, delay, pulmonary tuberculosis, out of pocket expenses
Procedia PDF Downloads 657 Insulin Resistance in Early Postmenopausal Women Can Be Attenuated by Regular Practice of 12 Weeks of Yoga Therapy
Authors: Praveena Sinha
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Context: Diabetes is a global public health burden, particularly affecting postmenopausal women. Insulin resistance (IR) is prevalent in this population, and it is associated with an increased risk of developing type 2 diabetes. Yoga therapy is gaining attention as a complementary intervention for diabetes due to its potential to address stress psychophysiology. This study focuses on the efficacy of a 12-week yoga practice in attenuating insulin resistance in early postmenopausal women. Research Aim: The aim of this research is to investigate the effect of a 3-month long yoga practice on insulin resistance in early postmenopausal women. Methodology: The study conducted a prospective longitudinal design with 67 women within five years of menopause. Participants were divided into two groups based on their willingness to join yoga. The Yoga group (n = 37) received routine gynecological management along with an integrated yoga module, while the Non-Yoga group (n = 30) received only routine management. Insulin resistance was measured using the homeostasis model assessment of insulin resistance (HOMA-IR) method before and after the intervention. Statistical analysis was performed using GraphPad Prism Version 5 software, with statistical significance set at P < 0.05. Findings: The results indicate a significant decrease in serum fasting insulin levels and HOMA-IR measurements in the Yoga group, although the decrease did not reach statistical significance. In contrast, the Non-Yoga group showed a significant rise in serum fasting insulin levels and HOMA-IR measurements after 3 months, suggesting a detrimental effect on insulin resistance in these postmenopausal women. Theoretical Importance: This study provides evidence that a 12-week yoga practice can attenuate the increase in insulin resistance in early postmenopausal women. It highlights the potential of yoga as a preventive measure against the early onset of insulin resistance and the development of type 2 diabetes mellitus. Regular yoga practice can be a valuable tool in addressing hormonal imbalances associated with early postmenopause, leading to a decrease in morbidity and mortality related to insulin resistance and type 2 diabetes mellitus in this population. Data Collection and Analysis Procedures: Data collection involved measuring serum fasting insulin levels and calculating HOMA-IR. Statistical analysis was performed using GraphPad Prism Version 5 software, and mean values with standard error of the mean were reported. The significance level was set at P < 0.05. Question Addressed: The study aimed to address whether a 3-month long yoga practice could attenuate insulin resistance in early postmenopausal women. Conclusion: The research findings support the efficacy of a 12-week yoga practice in attenuating insulin resistance in early postmenopausal women. Regular yoga practice has the potential to prevent the early onset of insulin resistance and the development of type 2 diabetes mellitus in this population. By addressing the hormonal imbalances associated with early post menopause, yoga could significantly decrease morbidity and mortality related to insulin resistance and type 2 diabetes mellitus in these subjects.Keywords: post menopause, insulin resistance, HOMA-IR, yoga, type 2 diabetes mellitus
Procedia PDF Downloads 686 Capability of a Single Antigen to Induce Both Protective and Disease Enhancing Antibody: An Obstacle in the Creation of Vaccines and Passive Immunotherapies
Authors: Parul Kulshreshtha, Subrata Sinha, Rakesh Bhatnagar
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This study was conducted by taking B. anthracis as a model pathogen. On infecting a host, B. anthracis secretes three proteins, namely, protective antigen (PA, 83kDa), edema factor (EF, 89 kDa) and lethal factor (LF, 90 kDa). These three proteins are the components of two anthrax toxins. PA binds to the cell surface receptors, namely, tumor endothelial marker (TEM) 8 and capillary morphogenesis protein (CMG) 2. TEM8 and CMG2 interact with LDL-receptor related protein (LRP) 6 for endocytosis of EF and LF. On entering the cell, EF acts as a calmodulin-dependent adenylate cyclase that causes a prolonged increase of cytosolic cyclic adenosine monophosphate (cAMP). LF is a metalloprotease that cleaves most isoforms of mitogen-activated protein kinase kinases (MAPKK/MEK) close to their N-terminus. By secreting these two toxins, B.anthracis ascertains death of the host. Once the systemic levels of the toxins rise, antibiotics alone cannot save the host. Therefore, toxin-specific inhibitors have to be developed. In this wake, monoclonal antibodies have been developed for the neutralization of toxic effects of anthrax toxins. We created hybridomas by using spleen of mice that were actively immunized with rLFn (recombinant N-terminal domain of lethal factor of B. anthracis) to obtain anti-toxin antibodies. Later on, separate group of mice were immunized with rLFn to obtain a polyclonal control for passive immunization studies of monoclonal antibodies. This led to the identification of one cohort of rLFn-immunized mice that harboured disease-enhancing polyclonal antibodies. At the same time, the monoclonal antibodies from all the hybridomas were being tested. Two hybridomas secreted monoclonal antibodies (H8 and H10) that were cross-reactive with EF (edema factor) and LF (lethal factor), while the other two hybridomas secreted LF-specific antibodies (H7 and H11). The protective efficacy of H7, H8, H10 and H11 was investigated. H7, H8 and H10 were found to be protective. H11 was found to have disease enhancing characteristics in-vitro and in mouse model of challenge with B. anthracis. In this study the disease enhancing character of H11 monoclonal antibody and anti-rLFn polyclonal sera was investigated. Combination of H11 with protective monoclonal antibodies (H8 and H10) reduced its disease enhancing nature both in-vitro and in-vivo. But combination of H11 with LETscFv (an scFv with VH and VL identical to H10 but lacking Fc region) could not abrogate the disease-enhancing character of H11 mAb. Therefore it was concluded that for suppression of disease enhancement, Fc portion was absolutely essential for interaction of H10 with H11. Our study indicates that the protective potential of an antibody depends equally on its idiotype/ antigen specificity and its isotype. A number of monoclonal and engineered antibodies are being explored as immunotherapeutics but it is absolutely essential to characterize each one for their individual and combined protective potential. Although new in the sphere of toxin-based diseases, it is extremely important to characterize the disease-enhancing nature of polyclonal as well as monoclonal antibodies. This is because several anti-viral therapeutics and vaccines have failed in the face of this phenomenon. The passive –immunotherapy thus needs to be well formulated to avoid any contraindications.Keywords: immunotherapy, polyclonal, monoclonal, antibody-dependent disease enhancement
Procedia PDF Downloads 3865 Optimizing Data Transfer and Processing in Multi-Cloud Environments for Big Data Workloads
Authors: Gaurav Kumar Sinha
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In an era defined by the proliferation of data and the utilization of cloud computing environments, the efficient transfer and processing of big data workloads across multi-cloud platforms have emerged as critical challenges. This research paper embarks on a comprehensive exploration of the complexities associated with managing and optimizing big data in a multi-cloud ecosystem.The foundation of this study is rooted in the recognition that modern enterprises increasingly rely on multiple cloud providers to meet diverse business needs, enhance redundancy, and reduce vendor lock-in. As a consequence, managing data across these heterogeneous cloud environments has become intricate, necessitating innovative approaches to ensure data integrity, security, and performance.The primary objective of this research is to investigate strategies and techniques for enhancing the efficiency of data transfer and processing in multi-cloud scenarios. It recognizes that big data workloads are characterized by their sheer volume, variety, velocity, and complexity, making traditional data management solutions insufficient for harnessing the full potential of multi-cloud architectures.The study commences by elucidating the challenges posed by multi-cloud environments in the context of big data. These challenges encompass data fragmentation, latency, security concerns, and cost optimization. To address these challenges, the research explores a range of methodologies and solutions. One of the key areas of focus is data transfer optimization. The paper delves into techniques for minimizing data movement latency, optimizing bandwidth utilization, and ensuring secure data transmission between different cloud providers. It evaluates the applicability of dedicated data transfer protocols, intelligent data routing algorithms, and edge computing approaches in reducing transfer times.Furthermore, the study examines strategies for efficient data processing across multi-cloud environments. It acknowledges that big data processing requires distributed and parallel computing capabilities that span across cloud boundaries. The research investigates containerization and orchestration technologies, serverless computing models, and interoperability standards that facilitate seamless data processing workflows.Security and data governance are paramount concerns in multi-cloud environments. The paper explores methods for ensuring data security, access control, and compliance with regulatory frameworks. It considers encryption techniques, identity and access management, and auditing mechanisms as essential components of a robust multi-cloud data security strategy.The research also evaluates cost optimization strategies, recognizing that the dynamic nature of multi-cloud pricing models can impact the overall cost of data transfer and processing. It examines approaches for workload placement, resource allocation, and predictive cost modeling to minimize operational expenses while maximizing performance.Moreover, this study provides insights into real-world case studies and best practices adopted by organizations that have successfully navigated the challenges of multi-cloud big data management. It presents a comparative analysis of various multi-cloud management platforms and tools available in the market.Keywords: multi-cloud environments, big data workloads, data transfer optimization, data processing strategies
Procedia PDF Downloads 674 Growth Mechanism and Sensing Behaviour of Sn Doped ZnO Nanoprisms Prepared by Thermal Evaporation Technique
Authors: Sudip Kumar Sinha, Saptarshi Ghosh
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While there’s a perpetual buzz around zinc oxide (ZnO) superstructures for their unique optical features, the versatile material has been constantly utilized to manifest tailored electronic properties through rendition of distinct morphologies. And yet, the unorthodox approach of implementing the novel 1D nanostructures of ZnO (pristine or doped) for volatile sensing applications has ample scope to accommodate new unconventional morphologies. In the last two decades, solid-state sensors have attracted much curiosity for their relevance in identifying pollutant, toxic and other industrial gases. In particular gas sensors based on metal oxide semiconducting (wide Eg) nanomaterials have recently attracted intensive attention owing to their high sensitivity and fast response and recovery time. These materials when exposed to air, the atmospheric O2 dissociates and get absorb on the surface of the sensors by trapping the outermost shell electrons. Finally a depleted zone on the surface of the sensors is formed, that enhances the potential barrier height at grain boundary . Once a target gas is exposed to the sensor, the chemical interaction between the chemisorbed oxygen and the specific gas liberates the trapped electrons. Therefore altering the amount of adsorbate is a considerable approach to improve the sensitivity of any target gas/vapour molecule. Likewise, this study presents a spontaneous but self catalytic creation of Sn-doped ZnO hexagonal nanoprisms on Si (100) substrates through thermal evaporation-condensation method, and their subsequent deployment for volatile sensing. In particular, the sensors were utilized to detect molecules of ethanol, acetone and ammonia below their permissible exposure limits which returned sensitivities of around 85%, 80% and 50% respectively. The influence of Sn concentration on the growth, microstructural and optical properties of the nanoprisms along with its role in augmenting the sensing parameters has been detailed. The single-crystalline nanostructures have a typical diameter ranging from 300 to 500 nm and a length that extends up to few micrometers. HRTEM images confirmed the hexagonal crystallography for the nanoprisms, while SAED pattern asserted the single crystalline nature. The growth habit is along the low index <0001>directions. It has been seen that the growth mechanism of the as-deposited nanostructures are directly influenced by varying supersaturation ratio, fairly high substrate temperatures, and specified surface defects in certain crystallographic planes, all acting cooperatively decide the final product morphology. Room temperature photoluminescence (PL) spectra of this rod like structures exhibits a weak ultraviolet (UV) emission peak at around 380 nm and a broad green emission peak in the 505 nm regime. An estimate of the sensing parameters against dispensed target molecules highlighted the potential for the nanoprisms as an effective volatile sensing material. The Sn-doped ZnO nanostructures with unique prismatic morphology may find important applications in various chemical sensors as well as other potential nanodevices.Keywords: gas sensor, HRTEM, photoluminescence, ultraviolet, zinc oxide
Procedia PDF Downloads 2403 OpenFOAM Based Simulation of High Reynolds Number Separated Flows Using Bridging Method of Turbulence
Authors: Sagar Saroha, Sawan S. Sinha, Sunil Lakshmipathy
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Reynolds averaged Navier-Stokes (RANS) model is the popular computational tool for prediction of turbulent flows. Being computationally less expensive as compared to direct numerical simulation (DNS), RANS has received wide acceptance in industry and research community as well. However, for high Reynolds number flows, the traditional RANS approach based on the Boussinesq hypothesis is incapacitated to capture all the essential flow characteristics, and thus, its performance is restricted in high Reynolds number flows of practical interest. RANS performance turns out to be inadequate in regimes like flow over curved surfaces, flows with rapid changes in the mean strain rate, duct flows involving secondary streamlines and three-dimensional separated flows. In the recent decade, partially averaged Navier-Stokes (PANS) methodology has gained acceptability among seamless bridging methods of turbulence- placed between DNS and RANS. PANS methodology, being a scale resolving bridging method, is inherently more suitable than RANS for simulating turbulent flows. The superior ability of PANS method has been demonstrated for some cases like swirling flows, high-speed mixing environment, and high Reynolds number turbulent flows. In our work, we intend to evaluate PANS in case of separated turbulent flows past bluff bodies -which is of broad aerodynamic research and industrial application. PANS equations, being derived from base RANS, continue to inherit the inadequacies from the parent RANS model based on linear eddy-viscosity model (LEVM) closure. To enhance PANS’ capabilities for simulating separated flows, the shortcomings of the LEVM closure need to be addressed. Inabilities of the LEVMs have inspired the development of non-linear eddy viscosity models (NLEVM). To explore the potential improvement in PANS performance, in our study we evaluate the PANS behavior in conjugation with NLEVM. Our work can be categorized into three significant steps: (i) Extraction of PANS version of NLEVM from RANS model, (ii) testing the model in the homogeneous turbulence environment and (iii) application and evaluation of the model in the canonical case of separated non-homogeneous flow field (flow past prismatic bodies and bodies of revolution at high Reynolds number). PANS version of NLEVM shall be derived and implemented in OpenFOAM -an open source solver. Homogeneous flows evaluation will comprise the study of the influence of the PANS’ filter-width control parameter on the turbulent stresses; the homogeneous analysis performed over typical velocity fields and asymptotic analysis of Reynolds stress tensor. Non-homogeneous flow case will include the study of mean integrated quantities and various instantaneous flow field features including wake structures. Performance of PANS + NLEVM shall be compared against the LEVM based PANS and LEVM based RANS. This assessment will contribute to significant improvement of the predictive ability of the computational fluid dynamics (CFD) tools in massively separated turbulent flows past bluff bodies.Keywords: bridging methods of turbulence, high Re-CFD, non-linear PANS, separated turbulent flows
Procedia PDF Downloads 1452 Development & Standardization of a Literacy Free Cognitive Rehabilitation Program for Patients Post Traumatic Brain Injury
Authors: Sakshi Chopra, Ashima Nehra, Sumit Sinha, Harsimarpreet Kaur, Ravindra Mohan Pandey
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Background: Cognitive rehabilitation aims to retrain brain injured individuals with cognitive deficits to restore or compensate lost functions. As illiterates or people with low literacy levels represent a significant proportion of the world, specific rehabilitation modules for such populations are indispensable. Literacy is significantly associated with all neuropsychological measures and retraining programs widely use written or spoken techniques which essentially require the patient to read or write. So, the aim of the study was to develop and standardize a literacy free neuropsychological rehabilitation program for improving cognitive functioning in patients with mild and moderate Traumatic Brain Injury (TBI). Several studies have pointed out to the impairments seen in memory, executive functioning, and attention and concentration post-TBI, so the rehabilitation program focussed on these domains. Visual item memorization, stick constructions, symbol cancellations, and colouring techniques were used to construct the retraining program. Methodology: The development of the program consisted of planning, preparing, analyzing, and revising the different modules. The construction focussed on areas of retraining immediate and delayed visual memory, planning ability, focused and divided attention, concentration, and response inhibition (to control irritability and aggression). A total of 98 home based retraining modules were prepared in the 4 domains (42 for memory, 42 for executive functioning, 7 for attention and concentration, and 7 for response inhibition). The standardization was done on 20 healthy controls to review, select and edit items. For each module, the time, errors made and errors per second were noted down, to establish the difficulty level of each module and were arranged in increasing level of difficulty over a period of 6 weeks. The retraining tasks were then administered on 11 brain injured individuals (5 after Mild TBI and 6 after Moderate TBI). These patients were referred from the Trauma Centre to Clinical Neuropsychology OPD, All India Institute of Medical Sciences, New Delhi, India. Results: The time was taken, errors made and errors per second were analysed for all domains. Education levels were divided into illiterates, up to 10 years, 10 years to graduation and graduation and above. Mean and standard deviations were calculated. Between group and within group analysis was done using the t-test. The performance of 20 healthy controls was analyzed and only a significant difference was observed on the time taken for the attention tasks and all other domains had non-significant differences in performance between different education levels. Comparing the errors, time taken between patient and control group, there was a significant difference in all the domains at the 0.01 level except the errors made on executive functioning, indicating that the tool can successfully differentiate between healthy controls and patient groups. Conclusions: Apart from the time taken for symbol cancellations, the entire cognitive rehabilitation program is literacy free. As it taps the major areas of impairment post-TBI, it could be a useful tool to rehabilitate the patient population with low literacy levels across the world. The next step is already underway to test its efficacy in improving cognitive functioning in a randomized clinical controlled trial.Keywords: cognitive rehabilitation, illiterates, India, traumatic brain injury
Procedia PDF Downloads 3331 Cognitive Decline in People Living with HIV in India and Correlation with Neurometabolites Using 3T Magnetic Resonance Spectroscopy (MRS): A Cross-Sectional Study
Authors: Kartik Gupta, Virendra Kumar, Sanjeev Sinha, N. Jagannathan
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Introduction: A significant number of patients having human immunodeficiency virus (HIV) infection show a neurocognitive decline (NCD) ranging from minor cognitive impairment to severe dementia. The possible causes of NCD in HIV-infected patients include brain injury by HIV before cART, neurotoxic viral proteins and metabolic abnormalities. In the present study, we compared the level of NCD in asymptomatic HIV-infected patients with changes in brain metabolites measured by using magnetic resonance spectroscopy (MRS). Methods: 43 HIV-positive patients (30 males and 13 females) coming to ART center of the hospital and HIV-seronegative healthy subjects were recruited for the study. All the participants completed MRI and MRS examination, detailed clinical assessments and a battery of neuropsychological tests. All the MR investigations were carried out at 3.0T MRI scanner (Ingenia/Achieva, Philips, Netherlands). MRI examination protocol included the acquisition of T2-weighted imaging in axial, coronal and sagittal planes, T1-weighted, FLAIR, and DWI images in the axial plane. Patients who showed any apparent lesion on MRI were excluded from the study. T2-weighted images in three orthogonal planes were used to localize the voxel in left frontal lobe white matter (FWM) and left basal ganglia (BG) for single voxel MRS. Single voxel MRS spectra were acquired with a point resolved spectroscopy (PRESS) localization pulse sequence at an echo time (TE) of 35 ms and a repetition time (TR) of 2000 ms with 64 or 128 scans. Automated preprocessing and determination of absolute concentrations of metabolites were estimated using LCModel by water scaling method and the Cramer-Rao lower bounds for all metabolites analyzed in the study were below 15\%. Levels of total N-acetyl aspartate (tNAA), total choline (tCho), glutamate + glutamine (Glx), total creatine (tCr), were measured. Cognition was tested using a battery of tests validated for Indian population. The cognitive domains tested were the memory, attention-information processing, abstraction-executive, simple and complex perceptual motor skills. Z-scores normalized according to age, sex and education standard were used to calculate dysfunction in these individual domains. The NCD was defined as dysfunction with Z-score ≤ 2 in at least two domains. One-way ANOVA was used to compare the difference in brain metabolites between the patients and healthy subjects. Results: NCD was found in 23 (53%) patients. There was no significant difference in age, CD4 count and viral load between the two groups. Maximum impairment was found in the domains of memory and simple motor skills i.e., 19/43 (44%). The prevalence of deficit in attention-information processing, complex perceptual motor skills and abstraction-executive function was 37%, 35%, 33% respectively. Subjects with NCD had a higher level of Glutamate in the Frontal region (8.03 ± 2.30 v/s. 10.26 ± 5.24, p-value 0.001). Conclusion: Among newly diagnosed, ART-naïve retroviral disease patients from India, cognitive decline was found in 53\% patients using tests validated for this population. Those with neurocognitive decline had a significantly higher level of Glutamate in the left frontal region. There was no significant difference in age, CD4 count and viral load at initiation of ART between the two groups.Keywords: HIV, neurocognitive decline, neurometabolites, magnetic resonance spectroscopy
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