Search results for: V. Ramesh Naidu

Authors: Kiran Kumar K., Ramesh Babu Bejjam, Atul Najan

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A thermosyphon system is a heat transfer loop which operates on the basis of gravity and buoyancy forces. It guarantees a good reliability and low maintenance cost as it does not involve any mechanical pump. Therefore it can be used in many industrial applications such as refrigeration and air conditioning, electronic cooling, nuclear reactors, geothermal heat extraction, etc. But flow instabilities and loop configuration are the major problems in this system. Several previous researchers studied that stabilities can be suppressed by using nanofluids as loop fluid. In the present study a rectangular thermosyphon loop with end heat exchangers are considered for the study. This configuration is more appropriate for many practical applications such as solar water heater, geothermal heat extraction, etc. In the present work, steady-state analysis is carried out on thermosyphon loop with parallel flow coaxial heat exchangers at heat source and heat sink. In this loop nano fluid is considered as the loop fluid and water is considered as the external fluid in both hot and cold heat exchangers. For this analysis one-dimensional homogeneous model is developed. In this model, conservation equations like conservation of mass, momentum, energy are discretized using finite difference method. A computer code is written in MATLAB to simulate the flow in thermosyphon loop. A comparison in terms of heat transfer is made between water and nano fluid as working fluids in the loop.

Keywords: heat exchanger, heat transfer, nanofluid, thermosyphon loop

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Authors: Ananthakrishna L. R., Ramesh D., Kumar Wodeyar, Kotresh A. M., Gururaj P. M.

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Malnad Gidda is the indigenous recognized cattle breed of Shivamogga District of Karnataka state, India is known for its disease resistance to many of the infectious diseases. There are 25 LRR (Leucine Rich Repeats) identified in bovine (Bos indicus) TLR9. The amino acid sequence of LRR is deduced to nucleotide sequence in BLASTx bioinformatic online tools. LRR2 to LRR10 are involved in pathogen recognition and binding in human TLR9 which showed a higher degree of nucleotide variations with respect to disease resistance to various pathogens. Hence, primers were designed to amplify the flanking sequences of LRR2 to LRR10, to discover the nucleotide variations if any, in Malnad Gidda breed of Cattle which is associated with disease resistance. The DNA isolated from peripheral blood mononuclear cells of ten Malnad Gidda cattle. A desired and specific amplification product of 0.8 kb was obtained at an annealing temperature of 56.6ᵒC. All the PCR products were sequenced on both sides by gene-specific primers. The sequences were compared with TLR9 sequence of cross breed cattle obtained from NCBI data bank. The sequence analysis between Malnad Gidda and crossbreed cattle revealed no nucleotide variations in the region LRR2 to LRR9 which shows the conserved in pathogen binding domain (LRR) of TLR9.

Keywords: leucine rich repeats, Malnad Gidda, cross breed, TLR9

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Authors: Ashish Jaiswal, Ashwin Ramesh Babu, Mohammad Zaki Zadeh, Fillia Makedon, Glenn Wylie

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Functional magnetic resonance imaging (fMRI) is a neuroimaging technique that records neural activations in the brain by capturing the blood oxygen level in different regions based on the task performed by a subject. Given fMRI data, the problem of predicting the state of cognitive fatigue in a person has not been investigated to its full extent. This paper proposes tackling this issue as a multi-class classification problem by dividing the state of cognitive fatigue into six different levels, ranging from no-fatigue to extreme fatigue conditions. We built a spatio-temporal model that uses convolutional neural networks (CNN) for spatial feature extraction and a long short-term memory (LSTM) network for temporal modeling of 4D fMRI scans. We also applied a self-supervised method called MoCo (Momentum Contrast) to pre-train our model on a public dataset BOLD5000 and fine-tuned it on our labeled dataset to predict cognitive fatigue. Our novel dataset contains fMRI scans from Traumatic Brain Injury (TBI) patients and healthy controls (HCs) while performing a series of N-back cognitive tasks. This method establishes a state-of-the-art technique to analyze cognitive fatigue from fMRI data and beats previous approaches to solve this problem.

Keywords: fMRI, brain imaging, deep learning, self-supervised learning, contrastive learning, cognitive fatigue

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Authors: Suhas Pednekar, Prashant Chavan, Ramesh Chaughule, Deepak Patkar

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Iron oxide (Fe3O4) magnetic nanoparticles (MNPs) are one of the most attractive nanomaterials for various biomedical applications. An important potential medical application of polymer-coated iron oxide nanoparticles (NPs) is as imaging agents. Composition, size, morphology and surface chemistry of these nanoparticles can now be tailored by various processes to not only improve magnetic properties but also affect the behavior of nanoparticles in vivo. MNPs are being actively investigated as the next generation of magnetic resonance imaging (MRI) contrast agents. Also, there is considerable interest in developing magnetic nanoparticles and their surface modifications with therapeutic agents. Our study involves the synthesis of biocompatible cancer drug coated with iron oxide nanoparticles and to evaluate their efficacy as MRI contrast agents. A simple and rapid microwave method to prepare Fe3O4 nanoparticles has been developed. The drug was successfully conjugated to the Fe3O4 nanoparticles which can be used for various applications. The relaxivity R2 (reciprocal of the spin-spin relaxation time T2) is an important factor to determine the efficacy of Fe nanoparticles as contrast agents for MRI experiments. R2 values of the coated magnetic nanoparticles were also measured using MRI technique and the results showed that R2 of the Fe complex consisting of Fe3O4, polymer and drug was higher than that of bare Fe nanoparticles and polymer coated nanoparticles. This is due to the increase in hydrodynamic sizes of Fe NPs. The results with various amounts of iron molar concentrations are also discussed. Using MRI, it is seen that the R2 relaxivity increases linearly with increase in concentration of Fe NPs in water.

Keywords: cancer drug, hydrodynamic size, magnetic nanoparticles, MRI

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Authors: Kalbende Krunal Ramesh

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The Carbon Capture and Storage Technology (CCS) provides a veritable platform to bridge the gap between the seemingly irreconcilable twin global challenges of ensuring a secure, reliable and diversified energy supply and mitigating climate change by reducing atmospheric emissions of carbon dioxide. Making its proper regulatory policy and making it flexible for the government and private company by law to regulate, also exploring the opportunity in this sector is the main aim of this paper. India's total annual emissions was 1725 Mt CO2 in 2011, which comprises of 6% of total global emission. It is very important to control the greenhouse gas emission for the environment protection. This paper discusses the various regulatory policy and technology adopted by some of the countries for successful using CCS technology. The brief geology of sedimentary basins in India is studied, ranging from the category I to category IV and deep water and potential for mature technology in CCS is reviewed. Areas not suitable for CO2 storage using presently mature technologies were over viewed. CSS and Clean development mechanism was developed for India, considering the various aspects from research and development, project appraisal, approval and validation, implementation, monitoring and verification, carbon credit issued, cap and trade system and its storage potential. The opportunities in oil and gas operations, power sector, transport sector is discussed briefly.

Keywords: carbon credit issued, cap and trade system, carbon capture and storage technology, greenhouse gas

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Authors: Ramesh Kumar, Rajesh Kumar, Shaktiman Singh, Atar Singh, Anshuman Bhardwaj, Ravindra Kumar Sinha, Anupma Kumari

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A detailed study of the ion chemistry of the Shaune Garnag glacier meltwater has been carried out to assess the role of active glacier in the chemical denudation rate. The chemical compositions of various ions in meltwater of the Shaune Garang glacier were analyzed during the melting period 2015 and 2016. Total 112 of melt water samples twice in a day were collected during ablation season of 2015 and 2016. To identify various factors controlling the dissolved ionic strength of Shaune Garang Glacier meltwater statistical analysis such as correlation matrix, Principle Component Analysis (PCA) and factor analysis were applied to deduce the result. Cation concentration for Ca²⁺ > Mg²⁺ > Na⁺ > K⁺ in the meltwater for both the years can be arranged in the order as Ca²⁺ > Mg²⁺ > Na⁺ > K⁺. Study showed that Ca²⁺ and HCO₃⁻ found to be dominant on the both melting period. Carbonate weathering identified as the dominant process controlling the dissolved ion chemistry of meltwater due to the high ratios of (Ca²⁺ + Mg²⁺) versus TZ+ and (Ca²⁺ + Mg²⁺) versus (Na⁺ + K⁺) in the study area. The cation denudation rate of the Shaune Garnag catchment is 3412.2 m⁻² a⁻¹, i.e. higher than the other glacierised catchment in the Himalaya, indicating intense chemical erosion in this catchment.

Keywords: Shaune Garang glacier, Hydrochemistry, chemical composition, cation denudation rate, carbonate weathering

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Authors: Ramesh Subramani, Mathivanan Narayanasamy, William Aalbersberg

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It is well accepted by last 35 years of research and on-going programmes that marine environment harbours abundant and unique biodiversity, which is currently playing as an important source in bioprospecting. It has become apparent that marine microorganisms are lead in the biodiscovery. Among marine organisms, actinobacteria are a target phylum for discovering novel antibiotics against increasing the multi-drug resistant human pathogens because of these taxa representing for novel genera and species. Marine actinomycetes are a proven source of new antibiotic leads and novel enzymes with important industrial applications. A total of 183 streptomycete and 25 non-streptomycete strains were isolated from different marine samples collected from north-eastern part of the Indian Ocean. Among them, 111 isolates displayed antibacterial activity against human pathogens and 151 exhibited antifungal activity against phytopathogens. Importantly, most of them produced various extracellular enzymes and 58 of them produced exopolysaccharides. Totally eight small bioactive compounds and a thermostable alkaline protease have been purified from a selected strain, Streptomyces fungicidicus. Besides, our on-going studies on non-streptomycete strains (rare actinomycetes) are most likely promising resource for new and unique compounds against current emerging drug-resistant pathogens. We have just recognised the chemical diversity in marine microorganisms. Therefore it is worthwhile to continue the exploration of marine microorganisms for new drug leads, novel enzymes and other bioprospecting research.

Keywords: bioactive compounds, industrial enzymes, marine actinobacteria, microbial metabolites, marine natural products

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Authors: Mohamed Abbas, Ramesh Singh

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This study investigates the hydrothermal aging behavior of undoped and copper oxide-doped alumina-toughened zirconia (ATZ). The ATZ ceramic composites underwent conventional sintering at temperatures ranging from 1250 to 1500°C with a holding time of 12 minutes. XRD analysis revealed a stable 100% tetragonal phase for conventionally sintered ATZ samples up to 1450°C, even after 100 hours of exposure. At 1500℃, XRD patterns of both undoped and doped ATZ samples showed no phase transformation after up to 3 hours of exposure to superheated steam. Extended exposure, however, resulted in phase transformation beyond 10 hours. CuO-doped ATZ samples initially exhibited lower monoclinic content, gradually increasing with aging. Undoped ATZ demonstrated better-aging resistance, maintaining ~40% monoclinic content after 100 hours. FESEM images post-aging revealed surface roughness changes due to the tetragonal-to-monoclinic phase transformation, with limited nucleation in the largest tetragonal grains. Fracture analysis exhibited macrocracks and microcracks on the transformed surface layer after aging. This study found that 0.2wt% CuO doping did not prevent the low-temperature degradation (LTD) phenomenon at elevated temperatures. Transformation zone depth (TZD) calculations supported the trend observed in the transformed monoclinic phase.

Keywords: alumina toughened zirconia, conventional sintering, copper oxide, hydrothermal ageing

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Authors: D. Karibasavaraja, Ramesh M.R., Sufiyan Ahmed, Noyonika M.R., Sameeksha A. V., Mamatha J., Samiksha S. Urs

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This research paper gives an overview of the experimental analysis of natural fibers with polymer composite. The whole world is concerned about conserving the environment. Henceforth, the demand for natural and decomposable materials is increasing. The application of natural fibers is widely used in aerospace for manufacturing aircraft bodies, and ship construction in navy fields. Based on the literature review, researchers and scientists are replacing synthetic fibers with natural fibers. The selection of these fibers mainly depends on lightweight, easily available, and economical and has its own physical and chemical properties and many other properties that make them a fine quality fiber. The pineapple fiber has desirable properties of good mechanical strength, high cellulose content, and fiber length. Hybrid composite was prepared using different proportions of pineapple fiber and banana fiber, and their ratios were varied in 90% polypropylene mixed with 5% banana fiber and 5% pineapple fiber, 85% polypropylene mixed with 7.5% banana fiber and 7.5% pineapple fiber and 80% polypropylene mixed with 10% banana fiber and 10% pineapple fiber. By impact experimental analysis, we concluded that the combination of 90% polypropylene and 5% banana fiber and 5% pineapple fiber exhibits a higher toughness value with mechanical strength. We also conducted scanning electron microscopy (SEM) analysis which showed better fiber orientation bonding between the banana and pineapple fibers with polypropylene composites. The main aim of the present research is to evaluate the properties of pineapple fiber and banana fiber reinforced with hybrid polypropylene composites.

Keywords: toughness, fracture, impact strength, banana fibers, pineapple fibers, tensile strength, SEM analysis

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Authors: Ramesh Nagarajappa, Upasana Mohapatra

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Considered a modern phobia, Nomophobia (NO MObile PHOne PhoBIA) is a term that describes the irrational fear or anxiety of being unable to access one’s own mobile phone. Objectives: To develop and validate the nomophobia questionnaire, administering it to a sample of adolescents representing undergraduate dental students. To assess the prevalence of Nomophobia, determine the usage pattern of mobile phones, and evaluate the impact due to lack of access to mobile phones among undergraduate dental students. Methodology: A cross-sectional study was conducted on 302 undergraduate students at Bhubaneswar through a self-administered questionnaire via Google Forms consisting of 19 items evaluating the pattern and anxiety related to usage of mobile phones. Responses were recorded on a 5-point Likert scale. Kruskal Wallis, Mann-Whitney U, and Chi-square tests were used for statistical analysis. Results: Test-Retest reliability showed kappa of k=0.86 and Internal consistency Chronbach’s-Alpha to be α=0.82. Prevalence of nomophobia (score ≥ 58) was 32.1%, and students at risk of being nomophobic (score 39-57) was 61.9%. It was highest in males (32.6%) and amongst the interns (41.9%) and lowest (25.5%) amongst the second-year students. Participants felt nervous/insecure if their phones were away from them because of the fear that somebody might have accessed their data (3.07±1.93) and or tried to contact them (3.09±1.13), which were not statistically significant (p>0.05). Conclusions: Effect of mobile phone on dental students and the fear of not having their phones with them is increasing elaborately, that needs to be controlled, which if not achieved, would negatively hamper their academic performance and their being in the society.

Keywords: addiction, dental students, mobile phone, nomophobia

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Authors: Kusum Kumari, Ramesh Banoth, V. S. Reddy Channu

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Organic-inorganic perovskite solar cells (PrSCs) have emerged as a promising solar photovoltaic technology in terms of realizing high power conversion efficiency (PCE). However, their limited lifetime and poor device stability limits their commercialization in future. In this regard, interface engineering of the electron transport layer (ETL) using 2D materials have been currently used owing to their high carrier mobility, high thermal stability and tunable work function, which in turn enormously impact the charge carrier dynamics. In this work, we report an easy and effective way of simultaneously enhancing the efficiency of PrSCs along with the long-term stability through interface engineering via the incorporation of 2D-Molybdenum disulfide (2D-MoS₂, few layered nanoflakes) in mesoporous-Titanium dioxide (mp-TiO₂)scaffold electron transport buffer layer, and using poly 3-hexytheophene (P3HT) as hole transport layers. The PSCs were fabricated in ambient air conditions in device configuration, FTO/c-TiO₂/mp-TiO₂:2D-MoS₂/CH3NH3PbI3/P3HT/Au, with an active area of 0.16 cm². The best device using c-TiO₂/mp-TiO₂:2D-MoS₂ (0.5wt.%) ETL exhibited a substantial increase in PCE ~13.04% as compared to PCE ~8.75% realized in reference device fabricated without incorporating MoS₂ in mp-TiO₂ buffer layer. The incorporation of MoS₂ nanoflakes in mp-TiO₂ ETL not only enhances the PCE to ~49% but also leads to better device stability in ambient air conditions without encapsulation (retaining PCE ~86% of its initial value up to 500 hrs), as compared to ETLs without MoS₂.

Keywords: perovskite solar cells, MoS₂, nanoflakes, electron transport layer

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Authors: Saeed Bagherifam, Trevor Brown, Chris Fellows, Ravi Naidu

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Over the last century, rapid urbanization, industrial emissions, and mining activities have resulted in widespread contamination of the environment by heavy metal(loid)s. Arsenic (As) is a toxic metalloid belonging to group 15 of the periodic table, which occurs naturally at low concentrations in soils and the earth’s crust, although concentrations can be significantly elevated in natural systems as a result of dispersion from anthropogenic sources, e.g., mining activities. Bioavailability is the fraction of a contaminant in soils that is available for uptake by plants, food chains, and humans and therefore presents the greatest risk to terrestrial ecosystems. Numerous attempts have been made to establish in situ and ex-situ technologies of remedial action for remediation of arsenic-contaminated soils. In situ stabilization techniques are based on deactivation or chemical immobilization of metalloid(s) in soil by means of soil amendments, which consequently reduce the bioavailability (for biota) and bioaccessibility (for humans) of metalloids due to the formation of low-solubility products or precipitates. This study investigated the effectiveness of two different types of synthetic manganese and iron oxides (birnessite and goethite) for stabilization of As in a soil spiked with 1000 mg kg⁻¹ of As and treated with 10% dosages of soil amendments. Birnessite was made using HCl and KMnO₄, and goethite was synthesized by the dropwise addition of KOH into Fe(NO₃) solution. The resulting contaminated soils were subjected to a series of chemical extraction studies including sequential extraction (BCR method), single-step extraction with distilled (DI) water, 2M HNO₃ and simplified bioaccessibility extraction tests (SBET) for estimation of bioaccessible fractions of As in two different soil fractions ( < 250 µm and < 2 mm). Concentrations of As in samples were measured using inductively coupled plasma mass spectrometry (ICP-MS). The results showed that soil with birnessite reduced bioaccessibility of As by up to 92% in both soil fractions. Furthermore, the results of single-step extractions revealed that the application of both birnessite and Goethite reduced DI water and HNO₃ extractable amounts of arsenic by 75, 75, 91, and 57%, respectively. Moreover, the results of the sequential extraction studies showed that both birnessite and goethite dramatically reduced the exchangeable fraction of As in soils. However, the amounts of recalcitrant fractions were higher in birnessite, and Goethite amended soils. The results revealed that the application of both birnessite and goethite significantly reduced bioavailability and the exchangeable fraction of As in contaminated soils, and therefore birnessite and Goethite amendments might be considered as promising adsorbents for stabilization and remediation of As contaminated soils.

Keywords: arsenic, bioavailability, in situ stabilisation, metalloid(s) contaminated soils

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Authors: ShyamKrishna Kirithivasan, Shreyas Battula, Aditi Soori, Richa Ramesh, Ramamoorthy Srinath

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The human brain, among the most complex and mysterious aspects of the body, harbors vast potential for extensive exploration. Unraveling these enigmas, especially within neural perception and cognition, delves into the realm of neural decoding. Harnessing advancements in generative AI, particularly in Visual Computing, seeks to elucidate how the brain comprehends visual stimuli observed by humans. The paper endeavors to reconstruct human-perceived visual stimuli using Functional Magnetic Resonance Imaging (fMRI). This fMRI data is then processed through pre-trained deep-learning models to recreate the stimuli. Introducing a new architecture named LatentNeuroNet, the aim is to achieve the utmost semantic fidelity in stimuli reconstruction. The approach employs a Latent Diffusion Model (LDM) - Stable Diffusion v1.5, emphasizing semantic accuracy and generating superior quality outputs. This addresses the limitations of prior methods, such as GANs, known for poor semantic performance and inherent instability. Text conditioning within the LDM's denoising process is handled by extracting text from the brain's ventral visual cortex region. This extracted text undergoes processing through a Bootstrapping Language-Image Pre-training (BLIP) encoder before it is injected into the denoising process. In conclusion, a successful architecture is developed that reconstructs the visual stimuli perceived and finally, this research provides us with enough evidence to identify the most influential regions of the brain responsible for cognition and perception.

Keywords: BLIP, fMRI, latent diffusion model, neural perception.

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Authors: K. A. Ramesh

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Purpose: The study is to find out the effect of isolated and combined aerobic and anaerobic interval training on stride length and stride frequency of Soccer players. Method(s): To achieve this purpose, 45 women Soccer players who participated in the Anna University, Tamilnadu, India. Intercollegiate Tournament was selected as subjects and were randomly divided into three equal groups of fifteen each, such as an anaerobic interval training group (group-I), anaerobic interval training group (group-II) and combined aerobic-anaerobic interval training group (group-III). The training program was conducted three days per weeks for a period of six weeks. Stride length and Stride frequency was selected as dependent variables. All the subjects of the three groups were tested on selected criterion variables at prior to and immediately after the training program. The concepts of dependent test were employed to find out the significant improvement due to the influence of training programs on all the selected criterion variables. The analysis of covariance (ANCOVA) was also used to analyze the significant difference, if, any among the experimental groups. Result(s): The result of the study revealed that combined group was higher than aerobic interval training and anaerobic interval training groups. Conclusion(s): It was concluded that when experimental groups were compared with each other, the combined aerobic – anaerobic interval training program was found to be greater than the aerobic and the anaerobic interval training programs on the development of stride length and stride frequency. High intensity, combined aerobic – anaerobic interval training program can be carried out in a more soccer specific way than plain running.

Keywords: stride length, stride frequency, interval training, soccer

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Authors: Bhawna Chandravanshi, Ramesh Bhonde

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In the present study, we focused on the improvisation of islet survival in hypoxia. The Islet-like cell aggregates (ICAs) derived from Wharton's jelly mesenchymal stem cells (WJ-MSC) were cultured with and without WJ-MSC for 48h in hypoxia and normoxia and tested for their direct trophic effect on β cell survival. The WJ MSCs themselves secreted insulin upon glucose challenge and expressed the pancreatic markers at both transcription and translational level (C-peptide, Insulin, Glucagon and Glut 2). Direct contact of MSCs with ICAs facilitate the highest viability under hypoxia as evidenced by fluorescein diacetate/propidium iodide and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cytokine analysis of the co-cultured ICAs revealed amplification of anti-inflammatory cytokine-like TGFβ and TNFα accompanied by depletion of pro-inflammatory cytokines. The increment in VEGF and PDGFa was also seen showing their ability to vascularize upon transplantation. This was further accompanied by reduction in total reactive oxygen species, nitric oxide, and super oxide ions and down-regulation of Caspase3, Caspase8, p53 and up regulation of Bcl2 confirming prevention of apoptosis in ICAs. There was a significant reduction in the expression of p38 protein in the presence of MSCs making the ICAs responsive to glucose. Taken together our data demonstrate for the first time that the WJ-MSC expressed pancreatic markers and their supplementation protected engineered islets against hypoxia, oxidative stress, and inflammatory cytokines by inhibiting p38 MAPK protein.

Keywords: hypoxia, islet-like cell aggregates, inflammatory cytokines, oxidative stress

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Authors: Spandana Ramisetty, Mandan Chidambaram, Ramesh Bhujade

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Algal biomass is not only a potential source for biocrude but also for high value chemicals like carotenoids, fatty acids, proteins, polysaccharides, vitamins etc. Astaxanthin is one such high value vital carotenoid which has extensive applications in pharmaceutical, aquaculture, poultry and cosmetic industries and expanding as dietary supplement to humans. Green microalgae Haematococcus pluvialis is identified as the richest natural source of astaxanthin and is the key source of commercial astaxanthin. Several extraction processes from wet and dry Haematococcus pluvialis biomass have been explored by researchers. Extraction with supercritical CO₂ and various physical disruption techniques like mortar and pestle, homogenization, ultrasonication and ball mill from dried algae are widely used extraction methods. However, these processes require energy intensive drying of biomass that escalates overall costs notably. From the process economics perspective, it is vital to utilize wet processing technology in order to eliminate drying costs. Hydrothermal liquefaction (HTL) is a thermo-chemical conversion process that converts wet biomass containing over 80% water to bio-products under high temperature and high pressure conditions. Astaxanthin is a lipid soluble pigment and is usually extracted along with lipid component. Mild HTL at 200°C and 60 bar has been demonstrated by researchers in a microfluidic platform achieving near complete extraction of astaxanthin from wet biomass. There is very limited work done in this field. An integrated approach of sequential HTL offers cost-effective option to extract astaxanthin/lipid from wet algal biomass without drying algae and also recovering water, minerals and nutrients. This paper reviews past work and evaluates the astaxanthin extraction processes with focus on hydrothermal extraction.

Keywords: astaxanthin, extraction, high value chemicals, hydrothermal liquefaction

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Authors: Ramesh Kumar Behera, Md. Izhar Hassan

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Accident investigation and analysis are useful to identify deficiencies in plant, process, and management practices and formulate preventive strategies for injury elimination. In India and other parts of the world, industrial accidents are investigated to know the causes and also to fulfill legal compliances. However, findings of investigation are seldom used appropriately to strengthen Occupational Safety and Health (OSH) in expected lines. The mineral rich state of Odisha in eastern coast of India; known as a hub for Iron and Steel industries, witnessed frequent accidents during 2005-2009. This article based on study of 982 fatal ‘factory-accidents’ occurred in Odisha during the period 2001-2016, discusses the ‘turnaround-story’ resulting in reduction of fatal accident from 122 in 2009 to 45 in 2016. This paper examines various factors causing incidents; accident pattern in steel and chemical sector; role of climate and harsh weather conditions on accident causation. Software such as R, SQL, MS-Excel and Tableau were used for analysis of data. It is found that maximum fatality is caused due to ‘fall from height’ (24%); steel industries are relatively more accident prone; harsh weather conditions of summer increase chances of accident by 20%. Further, the study suggests that enforcement of partial work-restriction around lunch time during peak summer, screening and training of employees reduce accidents due to fall from height. The study indicates that learning from accident investigation and analysis can be used as a method to reduce work related accidents in the journey towards ‘Vision Zero’.

Keywords: accident investigation and analysis, fatal accidents in India, fall from height, vision zero

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Authors: V. Kuzhandai Velu, R. Ramesh

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Background and objectives: Acute myocardial infarction (AMI) is the most common cause of mortality and morbidity. Over the last decade, microRNAs (miRs) have emerged as a potential marker for detecting AMI. The current study evaluates the kinetics and importance of miRs in the differential diagnosis of ST-segment elevated MI (STEMI) and non-STEMI (NSTEMI) and its correlation to conventional biomarkers and to predict the immediate outcome of AMI for arrhythmias and left ventricular (LV) dysfunction. Materials and Method: A total of 100 AMI patients were recruited for the study. Routine cardiac biomarker and miRNA levels were measured during diagnosis and serially at admission, 6, 12, 24, and 72hrs. The baseline biochemical parameters were analyzed. The expression of miRs was compared between STEMI and NSTEMI at different time intervals. Diagnostic utility of miR-1, miR-133, miR-208, and miR-499 levels were analyzed by using RT-PCR and with various diagnostics statistical tools like ROC, odds ratio, and likelihood ratio. Results: The miR-1, miR-133, and miR-499 showed peak concentration at 6 hours, whereas miR-208 showed high significant differences at all time intervals. miR-133 demonstrated the maximum area under the curve at different time intervals in the differential diagnosis of STEMI and NSTEMI which was followed by miR-499 and miR-208. Evaluation of miRs for predicting arrhythmia and LV dysfunction using admission sample demonstrated that miR-1 (OR = 8.64; LR = 1.76) and miR-208 (OR = 26.25; LR = 5.96) showed maximum odds ratio and likelihood respectively. Conclusion: Circulating miRNA showed a highly significant difference between STEMI and NSTEMI in AMI patients. The peak was much earlier than the conventional biomarkers. miR-133, miR-208, and miR-499 can be used in the differential diagnosis of STEMI and NSTEMI, whereas miR-1 and miR-208 could be used in the prediction of arrhythmia and LV dysfunction, respectively.

Keywords: myocardial infarction, cardiac biomarkers, microRNA, arrhythmia, left ventricular dysfunction

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Authors: Hannah Rachel Vasanthi, Paomipem Phazang, Veereshkumar, Sali, Ramesh Parjapath, Sangeetha Marimuthu Kannan

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Garcinia indica (G. indica) fruit rind extract commonly used in South Indian culinary and Indian System of medicines is reported to exhibit various biological activities. The present study envisages the influence of the phytoconstituents in G. indica extract (Vrikshamla capsules- a herbal supplement) on diabetic condition. The condition of type 2 diabetes was triggered in experimental animals by feeding high fat diet for 8 weeks followed by a sub-diabetogenic dose of 35mg/kg bw of streptozotocin intraperitoneally. Oral supplementation of the extract at two doses (100 and 200 mg/kg body weight) for 14 days reduced hyperglycemia, hypercholesterolemia and dyslipidemia (p< 0.001). Pathophysiological changes of obesity and diabetes associated complications majorly mediated by oxidative stress were analyzed by measuring the markers of oxidative stress such as lipid peroxidation, enzymatic (SOD, Catalase, GPx) and non-enzymatic markers (GSH). Conspicuous changes markers were noticed in diabetic condition which was reverted by the G. indica extract. Screening the extract by AccuTOF-DART (MS) revealed the presence of hydroxycitric acid and garcinol in abundant quantity which probably has influenced the biological activity. This was also corroborated through docking studies of hydroxycitric acid and garcinol both individually and synergistically with the antioxidant proteins. Altogether, hydroxycitric acid and garcinol present in G. indica fruit extract alleviates the pathophysiological conditions such as hyperglycemia, dyslipidemia, insulin resistance and oxidative stress mediated by diabesity.

Keywords: antioxidants , diabesity, hydroxycitric acid, garcinol, Garcinia indica, sreptozotocin

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Authors: Ramesh K. Adsul, V. R. Shinde, S. S. Jadhav

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The main aim of the present study was to explore the effect of various levels of parental acceptance – avoidance attitude on various areas of adjustment of urban and rural junior college students. It was hypothesized that 1. There exists no significant effect of various levels of parental acceptance attitude on adjustment of urban and rural junior college students. 2. There exists no significant effect of various levels of parental avoidance attitude on adjustment of urban and rural junior college students. 3. There would be no significant difference between urban and rural Junior College students on various areas of (home, health, social, and emotional) adjustment. The 847 students (427 boys and 420 girls) studying in 11th class of various Junior colleges in Sangli ,Satara and Kolhapur districts of Maharashtra State, India were selected by random sampling method. Study was conducted by using two psychological tests namely 1. Family Relationship Inventory. 2.Bell’s Adjustment Inventory. One way ANOVA was employed to find out the effect of parental acceptance – avoidance attitude and adjustment in various areas of urban and rural junior college students. ‘t’ test was used to find out the difference between urban and rural students on various areas of adjustment. The results of the study indicate that (1) It is observed that three groups of parental acceptance attitude (PA) are significantly varied on home and social adjustment. It means that PA affects home and social adjustment of adolescents. High PA creates excellent adjustment and low PA creates poor adjustment in adolescents. (2) Study revealed that PV significantly affects adjustment of adolescents. High PV significantly creates poor adjustment in adolescents than average and low PV. (3) There is significant difference between urban and rural adolescents on adjustment. Urban adolescents have better adjustment than rural adolescents.

Keywords: parental acceptance, avoidance attitude, adjustment, urban-rural student

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Authors: P. S. Dhananjaya Swamy, B. Chinnappa, G. B. Ramesh, Naveen P. Kumar

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Kodagu district is one of the most densely forested districts in the India as around sixty five per cent of geographical areas under tree cover. Nearly 53 per cent of the flora of Kodagu is endemic. The district is also a hotspot of endemic orchids found mainly in the Thadiandamol. Shade grown, eco-friendly coffee farms are perhaps a selected few places on this planet where nature runs wild. The Kodagu accounts for more than 8.8 per cent of floral diversity of Karnataka state. Estimation of unit cost of cultivation plays a vital role in determining the governmental program their market intervention policies. On an average, planters incurred around Rs. 17041 per acre. The extent of production risk was highest among small category of planters (66 %) compared to other two exhibiting production instability. The result shows that, the coffee productivity in medium plantations was 1051.2 kg per acre as against 758.5 and 789.2 kg in the case of small and large plantations. An annual net return per acre was highest in the case of medium planters (Rs. 26109.3) as against Rs. 20566.7 and Rs. 18572.7 in the case of small and large planters. Cost of production was lowest in the case of small planters (Rs. 18.9 per kg of output) followed by medium planters (Rs. 21.2 per kg of output) and large planters (Rs. 22.5 per kg of output). The productivity of coffee is less whenever it is grown under high shade and native tree cover; it is around 6 quintals per acre when compared with low shade conditions, which is around 8.9 quintals per acre, without a significant difference in the amount invested for growing coffee. Net gain was lower by Rs. 15.5 per kg for the planters growing under high shade and native trees cover when compared with low shade and exotic trees cover.

Keywords: coffee, cultivation, economics, Kodagu

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Authors: K. Geetha Ramesh, A. Ramachandraiah

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In an internal building space, daylight becomes a powerful source of illumination. The challenge therefore, is to develop means of utilizing both direct and diffuse natural light in buildings while maintaining and improving occupant's visual comfort, particularly at greater distances from the windows throwing daylight. The geometrical features of windows in a building have significant effect in providing daylight. The main goal of this research is to develop an innovative window geometry, which will effectively provide the daylight component adequately together with internal reflected component(IRC) and also the external reflected component(ERC), if any. This involves exploration of a light redirecting system using fractal geometry for windows, in order to penetrate and distribute daylight more uniformly to greater depths, minimizing heat gain and glare, and also to reduce building energy use substantially. Of late the creation of fractal geometrical window and the occurrence of daylight illuminance due to such windows is becoming an interesting study. The amount of daylight can change significantly based on the window geometry and sky conditions. This leads to the (i) exploration of various fractal patterns suitable for window designs, and (ii) quantification of the effect of chosen fractal window based on the relationship between the fractal pattern, size, orientation and glazing properties for optimizing daylighting. There are a lot of natural lighting applications able to predict the behaviour of a light in a room through a traditional opening - a regular window. The conventional prediction methodology involves the evaluation of the daylight factor, the internal reflected component and the external reflected component. Having evaluated the daylight illuminance level for a conventional window, the technical performance of a fractal window for an optimal daylighting is to be studied and compared with that of a regular window. The methodologies involved are highlighted in this paper.

Keywords: daylighting, fractal geometry, fractal window, optimization

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Authors: R. Vimal, K. Hari Hara Subramaniyan, C. Aswin, B. Logeshwaran, M. Ramesh

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Due to several environmental concerns, natural fibers have greatly replaced the synthetic fibers as a reinforcing material in polymer matrix composites. Among the natural fibers, jute fibers are the most abundant plant fibers which are manufactured mainly in countries like India. In recent years, modification of plant fibers with range of chemicals to increase various mechanical and thermal properties has been focused greatly. Among that, some of the plant fibers were modified using succinic anhydride. In the present study, Jute fibers have been modified chemically by treatment with succinic anhydride and glutaric anhydride at different concentrations of 5%, 10%, 20%, 30% and 40%. The fiber modification was done under retting condition at various retention times of 3, 6, 12, 24, 36, and 48 hours. The modification of fiber structure in both the cases is confirmed with Infrared Spectroscopy. The degree of modification increases with increase in retention time, but higher retention time has damaged the fiber structure which is common in both the cases. Comparatively, treatment of fibers with glutaric anhydride has shown efficient output than that of succinic anhydride. The unmodified fibers, succinylated fibers and glutarylated fibers at different retention times are reinforced with epoxy matrix at various volume fractions of fiber under room temperature. The composite made using unmodified fiber is used as a standard material. The tensile strength and flexural strength of the composites are analyzed in detail. Among these, the composite made with glutarylated fiber has shown good mechanical properties when compared to those made of succinylated and unmodified fiber.

Keywords: flexural strength, glutarylation, jute fibers, succinylation, tensile strength

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Authors: Chetan Gupta, Ramesh Gupta

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Unmanned aerial vehicles, of all sizes, are prime targets of the wing morphing concept as their lightweight structures demand high aerodynamic stability while traversing unsteady atmospheric conditions. In this research study, a hybrid morphing technology is developed to aid the trailing edge of the aircraft wing to alter its camber as a monolithic element rather than functioning as conventional appendages like flaps. Kinematic tailoring, actuation techniques involving shape memory alloys (SMA), piezoelectrics – individually fall short of providing a simplistic solution to the conundrum of morphing aircraft wings. On the other hand, the feature of negligible hysteresis while actuating using compliant mechanisms has shown higher levels of applicability and deliverability in morphing wings of even large aircrafts. This research paper delves into designing a wing section model with a periodic, multi-stable compliant structure requiring lower orders of topological optimization. The design is sub-divided into three smaller domains with external hyperelastic connections to achieve deflections ranging from -15° to +15° at the trailing edge of the wing. To facilitate this functioning, a hybrid actuation system by combining the larger bandwidth feature of piezoelectric macro-fibre composites and relatively higher work densities of shape memory alloy wires are used. Finite element analysis is applied to optimize piezoelectric actuation of the internal compliant structure. A coupled fluid-surface interaction analysis is conducted on the wing section during morphing to study the development of the velocity boundary layer at low Reynold’s numbers of airflow.

Keywords: compliant mechanism, hybrid morphing, piezoelectrics, shape memory alloys

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Authors: Ramesh Chand Chauhan, Sanjay Kumar Rai, Shashi kant, Rakesh Lodha, Nand Kumar

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Background: With a better understanding of HIV pathogenesis and availability of antiretroviral therapy more children are growing and entering in teenage group; informing children of their own HIV status has become an important aspect of long-term disease management. There is little evidence of how and when this type of disclosure takes place in a resource-limited setting. Methods: A cross-sectional study was conducted from June 2010 to May 2011 among a dyads of 156 HIV-infected children and their caregivers, those were visiting pediatric clinic at a tertiary care hospital in Delhi, India. The study protocol was approved by the Institute Ethics Committee. After taking written informed consent; pretested structured questionnaire was administered to caregivers during routine clinic visits. Information regarding socio-demographic characteristics, awareness of HIV infection status among children and their perception regarding disclosure was collected. Mean and frequencies were calculated and chi-square and logistic regression test were applied. Results: The mean age of children was 8.4 ±3.45 years. Among them 73.7% were male and 39.1% were orphans. Among 156 enrolled children, 74.4% (n=116) were of ≥ 6 years and were assessed for disclosure. Only 18.1% (n=21) children had been informed of their HIV status. Of those under 9 years, 6.4% knew their status, whereas 18.4% of 9-11 years and 35.5% of 12-14 years children knew they had HIV. Awareness among males (23.3%) was higher than females (3.3%). Both age and sex of child were significantly (p<0.01) associated with disclosure status. Other factors favoring disclosure were orphan-hood, non-perinatal mode of transmission (OR = 4.32; 95% CI 1.01-7.12), ART initiation (OR = 4.21; 95% CI 1.03-6.98), and caregiver educated beyond primary level (OR = 1.89; 95% CI 1.03-3.26). Repeated enquiry regarding the visit to clinic was the most common reason (66.6%) for disclosure. In 52.4% children disclosure was done with the involvement of other family members. 82.5% caregivers felt the age of > 10 years is appropriate for disclosing the HIV infection status to the child. Conclusion: Detailed guidelines on disclosure are required focusing on children of school-going age with perinatal infection who are not on ART and with caregivers of low educational status.

Keywords: HIV, children, India, disclosure

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Authors: Rohit Agarwal, Mrityunjay K. Singh, Soma Ghosh, Ramesh Shankar, Biswajit Ghosh, Vinay V. Mahashabde

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Thermo-mechanical treatment (TMT) of rebars is a critical process to impart sufficient strength and ductility to rebar. TMT rebars are produced by the Tempcore process, involves an 'in-line' heat treatment in which hot rolled bar (temperature is around 1080°C) is passed through water boxes where it is quenched under high pressure water jets (temperature is around 25°C). The quenching rate dictates composite structure consisting (four non-homogenously distributed phases of rebar microstructure) pearlite-ferrite, bainite, and tempered martensite (from core to rim). The ferrite and pearlite phases present at core induce ductility to rebar while martensitic rim induces appropriate strength. The TMT process is difficult to model as it brings multitude of complex physics such as heat transfer, highly turbulent fluid flow, multicomponent and multiphase flow present in the control volume. Additionally the presence of film boiling regime (above Leidenfrost point) due to steam formation adds complexity to domain. A coupled heat transfer and fluid flow model based on computational fluid dynamics (CFD) has been developed at product technology division of Tata Steel, India which efficiently predicts temperature profile and percentage martensite rim thickness of rebar during quenching process. The model has been validated with 16 mm rolling of New Bar mill (NBM) plant of Tata Steel Limited, India. Furthermore, based on the scenario analyses, optimal configuration of nozzles was found which helped in subsequent increase in rolling speed.

Keywords: boiling, critical heat flux, nozzles, thermo-mechanical treatment

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Authors: Ramesh Bhat, Ammu Somanath, A. K. Nayanatara

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Background: The increasing prevalence of overweight and obesity is a critical public health problem for women. The negative effect of stress on memory and cognitive functions has been widely explored for decades in numerous research projects using a wide range of methodology. Deterioration of memory and other brain functions are hallmarks of Alzheimer’s disease. Estrogen fluctuations and withdrawal have myriad direct effects on the central nervous system that have the potential to influence cognitive functions. Aim: The present study aims to compare the effect of stress on the cognitive functions in overweight/obese women before and after menopause. Material and Methods: A total of 142 female subjects constituting women before menopause between the age group of 18–44 years and women after menopause between the age group of 45–60 years were included in the sample. Participants were categorized into overweight/obese groups based on the body mass index. The Perceived Stress Scale (PSS) the major tool was used for measuring the perception of stress. Based on the stress scale measurement each group was classified into with stress and without stress. Addenbrooke’s cognitive Examination-III was used for measuring the cognitive functions. Results: Premenopausal women with stress showed a significant (P<0.05) decrease in the cognitive parameters such as attention and orientation Fluency, language and visuospatial ability. Memory did not show any significant change in this group. Whereas, in the postmenopausal stressed women all the cognitive functions except fluency showed a significant (P<0.05) decrease after menopause stressed group. Conclusion: Stress is a significant factor on the cognitive functions of obese and overweight women before and after menopause. Practice of Yoga, Encouragement in activities like gardening, embroidery, games and relaxation techniques should be recommended to prevent stress. Insights into the neurobiology before and after menopause can be gained from future studies examining the effect on the HPA axis in relation to cognition and stress.

Keywords: cognition, stress, premenopausal, body mass index

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Authors: Deepak Nathiya1, Ramesh Roop Rai, Pratima Singh1, Preeti Raj1, Supriya Suman, Balvir Singh Tomar

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Background: Sarcopenia is a catabolic state in liver cirrhosis (LC), accelerated with a breakdown of skeletal muscle to release amino acids which adversely affects survival, health-related quality of life, and response to any underlying disease. The primary objective of the study was to investigate the long-term effect of branched-chain amino acids (BCAA) supplementations on parameters associated with improved prognosis in sarcopenic patients with LC, as well as to evaluate its impact on cirrhotic-related events. Methods: We carried out a 24 week, single-center, randomized, open-label, controlled, two cohort parallel-group intervention trial comparing the efficacy of BCAA against lactoalbumin (L-ALB) on 106 sarcopenic liver cirrhotics. The BCAA (intervention) group was treated with 7.2 g BCAA per whereas, the lactoalbumin group was also given 6.3 g of L-Albumin. The primary outcome was to assess the impact of BCAA on parameters of sarcopenia: muscle mass, muscle strength, and physical performance. The secondary outcomes were to study combined survival and maintenance of liver function changes in laboratory and clinical markers in the duration of six months. Results: Treatment with BCAA leads to significant improvement in sarcopenic parameters: muscle strength, muscle function, and muscle mass. The total cirrhotic-related complications and cumulative event-free survival occurred fewer in the BCAA group than in the L-ALB group. Prognostic markers also improved significantly in the study. Conclusion: The current clinical trial demonstrated that long-term BCAAs supplementation improved sarcopenia and prognostic markers in patients with advanced liver cirrhosis.

Keywords: sarcopenia, liver cirrhosis, BCAA, quality of life

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Authors: Ishan Naidu, Jessica Ryvlin, Devin Videlefsky

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Introduction: Back pain is a leading cause of years lived with disability and economic burden, exceeding over $20 billion in healthcare costs not including indirect costs such as absence from work and caregiving. The multifactorial nature of back pain leads to treatment modalities administered by a variety of specialists, which are often disjointed. Multiple studies have found that patients receiving delayed physical therapy for lower back pain had higher medical-related costs from increased health service utilization as well as a reduced improvement in pain severity compared to early management. Uncoordinated health care delivery can exacerbate the physical and economic toll of the chronic condition, thus improvements in interdisciplinary, shared decision-making may improve outcomes. Objective: To assess whether a multidisciplinary spine clinic (MSC), consisting of orthopedic surgery, neurosurgery, pain medicine, and physiatry, alters interventional and non-interventional planning and treatment compared to a traditional unidisciplinary spine clinic (USC) including only orthopedic surgery. Methods: We conducted a retrospective cohort study with patients initially presenting for spine care to orthopedic surgeons between July 1, 2018 to June 30, 2019. Time to treatment recommendation, time to treatment and rates of treatment recommendations were assessed, including physical therapy, injections and surgery. Treatment rates were compared between MSC and USC using Pearson’s chi-square test logistic regression. Time to treatment recommendation and time to treatment were compared using log-rank test and Cox proportional hazard regression. All analyses were repeated for the propensity score (PS) matched subsample. Results: This study included 1,764 patients, with 692 at MSC and 1,072 at USC. Patients in MSC were more likely to be recommended injection when compared to USC (8.5% vs. 5.4%, p=0.01). When adjusted for confounders, the likelihood of injection recommendation remained greater in MSC than USC (Odds ratio [OR]=2.22, 95% CI: (1.39, 3.53), p=0.001). MSC was also associated with a shorter time to receiving injection recommendation versus USC (median: 21 vs. 32 days, log-rank: p<0.001; hazard ratio [HR]=1.90, 95% CI: (1.25, 2.90), p=0.003). MSC was associated with a higher likelihood of injection treatment (OR=2.27, 95% CI: (1.39, 3.73), p=0.001) and shorter lead time (HR=1.98, 95% CI: (1.27, 3.09), p=0.003). PS-matched analyses yielded similar conclusions. Conclusions: Care delivered at a multidisciplinary spine clinic was associated with a higher likelihood of recommending injection and a shorter lead time to injection administration when compared to a traditional unidisciplinary spine surgery clinic. Multidisciplinary clinics may facilitate coordinated care amongst different specialties resulting in increased utilization of less invasive treatment modalities while also improving care efficiency. The multidisciplinary clinic model is an important advancement in care delivery and communication, which can be used as a powerful method of improving patient outcomes as treatment guidelines evolve.

Keywords: coordinated care, epidural steroid injection, multi-disciplinary, non-invasive

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Authors: Pratap K. Chhotaray, Jitendriya Swain, Ashok Mishra, Ramesh L. Gardas

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Ionic liquids (ILs) are molten salts, consist predominantly of ions and found to be liquid below 100°C. The unparalleled growing interest in ILs is based upon their never ending design flexibility. The use of ILs as a co-solvent in binary as well as a ternary mixture with molecular solvents multifold it’s utility. Since polarity is one of the most widely applied solvent concepts which represents simple and straightforward means for characterizing and ranking the solvent media, its study for a binary mixture of ILs is crucial for its widespread application and development. The primary approach to the assessment of solution phase intermolecular interactions, which generally occurs on the picosecond to nanosecond time scales, is to exploit the optical response of photophysical probe. Pyrene butyric acid (PBA) is used as fluorescence probe due to its high quantum yield, longer lifetime and high solvent polarity dependence of fluorescence spectra. Propylammonium formate (PAF) is the IL used for this study. Both the UV-absorbance spectra and steady state fluorescence intensity study of PBA in different concentration of aqueous PAF, reveals that with an increase in PAF concentration, both the absorbance and fluorescence intensity increases which indicate the progressive solubilisation of PBA. Whereas, near about 50% of IL concentration, all of the PBA molecules get solubilised as there are no changes in the absorbance and fluorescence intensity. Furthermore, the ratio II/IV, where the band II corresponds to the transition from S1 (ν = 0) to S0 (ν = 0), and the band IV corresponds to transition from S1 (ν = 0) to S0 (ν = 2) of PBA, indicates that the addition of water into PAF increases the polarity of the medium. Time domain lifetime study shows an increase in lifetime of PBA towards the higher concentration of PAF. It can be attributed to the decrease in non-radiative rate constant at higher PAF concentration as the viscosity is higher. The monoexponential decay suggests that homogeneity of solvation environment whereas the uneven width at full width at half maximum (FWHM) indicates there might exist some heterogeneity around the fluorophores even in the water-IL mixed solvents.

Keywords: fluorescence, ionic liquid, lifetime, polarity, pyrene butyric acid

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