Fire Safety Analysis of a Railway Compartment using Computational Fluid Dynamics

Trains are considered to be the safest on-land transportation means for both passengers and cargo. Train accidents have been mainly disastrous, especially in case of fire, where the consequences are extensive loss of life and goods. The fire would generate smoke and heat which would spread quickly inside the railway compartments. Both heat and smoke are the primary reasons of casualties in a train. This study has been carried out to perform numerical analysis of fire characteristics in a railway compartment using commercial Computational Fluid Dynamics code ANSYS. Non-premixed combustion model has been used to simulate a fire scenario within a railway compartment, while Shear Stress Transport k-ω turbulence model has been used to accurately predict the hot air turbulence parameters within the compartment. The walls of the compartment have been modelled as no-slip stationary adiabatic walls, as is observed in real life conditions. Carbon dioxide concentration (CO2), temperature distribution and air flow velocity within the railway compartment has been monitored. It has been observed that the smoke above the fire source flows to both sides of the compartment. The highest temperature zone is located downstream the fire source, and gradually decreases with the increase in the distance from the fire source. It can be seen that CFD can be used as an effective tool in order to analyse the evolution of fire in railway compartments with reasonable accuracy. The paper also briefly discusses the topical reliability issues

Thinking beyond low-density lipoprotein cholesterol: strategies to further reduce cardiovascular risk

Several large statin trials and meta-analyses have demonstrated a reduction in low-density lipoprotein cholesterol (LDL-C) and cardiovascular morbidity and mortality. Some trials have also highlighted the significance of residual cardiovascular risk after treatment of LDL-C to target levels. This reflects the complex nature of residual cardiovascular risk. This residual risk is partially due to low HDL-C and high triglycerides (TG) despite achievement of LDL goals with statin therapy. The NCEP ATP III guidelines reported that low HDL-C is a significant and an independent risk factor for coronary heart disease (CHD) and is inversely related to CHD. Epidemiologic studies have also shown a similar inverse relationship of HDL-C with CHD. High-density lipoprotein cholesterol (HDL-C) may directly participate in the anti-atherogenic process by promoting efflux of cholesterol of the foam cells of atherogenic lesions. Many studies have demonstrated multiple anti-atherogenic actions of HDL-C and its role in promoting efflux of cholesterol from the foam cells. The residual risk by increased TG with or without low HDL-C can be assessed by calculating non–HDL-C and a reduction in TG results in decreased CHD

Lightweight MobileNet Model for Image Tempering Detection

In recent years, there has been a wide range of image manipulation identification challenges and an overview of image tampering detection and the relevance of applying deep learning models such as CNN and MobileNet for this purpose. The discussion then delves into the construction and setup of these models, which includes a block diagram as well as mathematical calculations for each layer. A literature study on Image tampering detection is also included in the discussion, comparing and contrasting various articles and their methodologies. The study then moves on to training and assessment datasets, such as the CASIA v2 dataset, and performance indicators like as accuracy and loss. Lastly, the performance characteristics of the MobileNet and CNN designs are compared. This work focuses on Image tampering detection using convolutional neural networks (CNNs) and the MobileNet architecture. We reviewed the MobileNet architecture's setup and block diagram, as well as its application to Image tampering detection. We also looked at significant literature on Image manipulation detection, such as major studies and their methodologies. Using the CASIA v2 dataset, we evaluated the performance of MobileNet and CNN architectures in terms of accuracy and loss. This paper offered an overview of the usage of deep learning and CNN architectures for image tampering detection and proved their accuracy in detecting manipulated images

SYNTHESIS, CHARACTERIZATION AND ELECTROCHEMICAL INVESTIGATION OF NOVEL 17-MEMBERED DIOXADIAZA NAPTHALDEHYDE BASED MACROCYCLIC LIGAND AND ITS COMPLEXES OF Co (III), Ni (II) AND Cu (II) PERCHLORATE IONS

Objective: The objective of this research is to synthesis hitherto, novel unreported [17]-membered dioxadiaza napthaldehyde based macrocyclic ligand (L) and to synthesize its Co(III), Ni(II) and Cu(II) metal ion complexes.Methods: The synthesis of the ligand has been accomplished by two different synthetic routes each involving two stages. 2-Hydroxy-1-Napthaldehyde in the presence of potassium carbonate was treated with α,α'-dibromo-m-xylene to yield the dial derivative (I). The dial derivative (I) was further made to undergo Schiff base condensation with 1,2-diaminobenzene to yield the bright yellow macrocycle (L) in good yield. In the second method the Schiff base condensed product Napthaloph was synthesized and allowed to undergo Williamson's condensation with α,α'-dibromo-m-xylene to yield the ligand (L).Results: The ligand and its complexes were characterized by elemental analysis, electronic spectroscopy, IR, Conductivity measurements, EPR, magnetic susceptibility, 1H NMR and MS. The neutral seventeen membered tetradentate dioxadiaza ligand (L) readily complexes with Co(III), Ni(II) and Cu(II) perchlorate salts in 1:1 mole ratio to yield complexes of formulae [Co(L)X2]ClO4, [Ni(L)X2], [Cu(L)X]ClO4, (X = Cl-, Br-and NO3-). The complexes were also synthesized by the metal template method. The yield of the template procedure was found to be greater than the non-template method.Conclusion: A hitherto 2, 10-dioxa-21,29-diaza-heptacyclo-[29.4.2.1[4,8].0[1,32].0[11,20].0[14,19].0[23,28].0[32,37]]-tetraconta-4, 6, 8, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39-octatecaene. The [17]-membered tetradentate dioxadiaza macrocycle (L) was found to accommodate Co3+, Ni2+, and Cu2+ions with ease due to the presence of flexible alkyl groups. Further studies with the inner-transition metal ions will be highly informative in understanding the coordinating capabilities of lanthanides and actinides.Â

A process optimization for bio-catalytic production of substituted catechols (3-nitrocatechol and 3-methylcatechol

<p>Abstract</p> <p>Background</p> <p>Substituted catechols are important precursors for large-scale synthesis of pharmaceuticals and other industrial products. Most of the reported chemical synthesis methods are expensive and insufficient at industrial level. However, biological processes for production of substituted catechols could be highly selective and suitable for industrial purposes.</p> <p>Results</p> <p>We have optimized a process for bio-catalytic production of 3-substituted catechols viz. 3-nitrocatechol (3-NC) and 3-methylcatechol (3-MC) at pilot scale. Amongst the screened strains, two strains viz. <it>Pseudomonas putida </it>strain (F1) and recombinant <it>Escherichia coli </it>expression clone (pDTG602) harboring first two genes of toluene degradation pathway were found to accumulate 3-NC and 3-MC respectively. Various parameters such as amount of nutrients, pH, temperature, substrate concentration, aeration, inoculums size, culture volume, toxicity of substrate and product, down stream extraction, single step and two-step biotransformation were optimized at laboratory scale to obtain high yields of 3-substituted catechols. Subsequently, pilot scale studies were performed in 2.5 liter bioreactor. The rate of product accumulation at pilot scale significantly increased up to ~90-95% with time and high yields of 3-NC (10 mM) and 3-MC (12 mM) were obtained.</p> <p>Conclusion</p> <p>The biocatalytic production of 3-substituted catechols viz. 3-NC and 3-MC depend on some crucial parameters to obtain maximum yields of the product at pilot scale. The process optimized for production of 3-substituted catechols by using the organisms <it>P. putida </it>(F1) and recombinant <it>E. coli </it>expression clone (pDTG602) may be useful for industrial application.</p

Shear Strength Behaviour of Clay Reinforced with Treated Coir Fibres

The effect of treated coir fibres on the shear strength behaviour of clay is presented in this study. A series of consolidated undrained test were performed on soil reinforced with untreated, sodium hydroxide treated and carbon tetrachloride treated fibres. The coir fibre content was varied from 0.4% to 1.6%. The results indicated that the deviator stress at failure of the clay and clay with untreated coir fibres can be increased by treatment with carbon tetrachloride and sodium hydroxide. A significant increase was also observed in shear strength parameters of clay reinforced with coir fibres at different percentages. The two parameter dependent hyperbolic models were used for predicting the experimental results. The back predicted stressstrain curve at dierent fibre percentage was found to compare well with the experimental results. The clay reinforced with untreated/treated coir fibres has shown improved strength behaviour, it can be used for short term stability problems

Elemental Analysis and Bioactivities of Ripe and Unripe Pericarp of Polyalthia longifolia (Annonaceae)

Polyalthia longifolia (Annonaceae) is an ornamental street tree having several medicinal values. The plant is used in traditional systems of medicine. The present study was conducted with an aim of estimating the content of minerals and determining bioactivities viz., antibacterial, cytotoxic and larvicidal activity of ripe and unripe pericarp of P. longifolia. The content of major and minor elements in powdered ripe and unripe pericarp was estimated by ICP-OES after microwave digestion using nitric acid. The pericarp powders were extracted using methanol and the extracts were subjected to preliminary phytochemical analysis. Antibacterial activity of pericarp extracts was determined against two Gram positive and three Gram negative bacteria by agar well diffusion assay. Cytotoxic potential of pericarp extracts was determined against two cell lines viz., HT-29 and MDA-MB-231 by MTT assay. Insecticidal activity, in terms of larvicidal activity of pericarp extracts was tested against II instar larvae of Aedes aegypti. The content of all elements except copper was highest in ripe pericarp. The content of potassium and iron was highest among major and minor elements respectively. Pericarp extracts caused dose dependent inhibition of test bacteria. Extract of ripe pericarp caused higher inhibition of test bacteria than extract of unripe pericarp. Both extracts showed concentration dependent cytotoxic effect. The cytotoxic effect of both the extract was pronounced against HT-29 than MDA-MB-231. The extracts exhibited dose dependent larvicidal effect. Among extracts, potent larvicidal activity was observed in case of ripe extract. Preliminary phytochemical analysis revealed the presence of flavonoids, tannins, saponins, steroids and glycosides in both the extracts. In conclusion, the ripe and unripe pericarp extracts of P. longifolia were found to contain various minerals in an appreciable quantity. The observed dose dependent bioactivities viz., antibacterial, cytotoxic and larvicidal activities might be ascribed to the presence of phytoconstituents. There is a great potential for the development of therapeutic agents from ripe and unripe pericarp. Further studies on isolation of active principles from pericarp extracts and their bioactivity determinations are under progress.Keywords: Polyalthia longifolia; Pericarp; Minerals; ICP-OES; Agar well diffusion; MTT;Larvicida

A Clinical Study of Jalaukavacharana in Varicose Eczema (Vicharchika)

In adolescents varicose eczema is a common skin condition encountered by general practitioners and dermatologists in day today clinical practices. Varicose eczema is the condition usually present secondary to varicosity of superficial veins. For this condition there is no successful surgery as well as medical remedy available for the complete cure. However in Ayurveda, Jalaukavacharana (Leech therapy) as a parasurgical method is useful in this condition. Leech is used for the bloodletting at that particular site. With this background a study has been conducted to compare the effect of Jalaukavacharana without and with internal medications, Two groups were done as Group-A and Group-B, each with 15 patients. Jalaukavacharana was done at eczema in Group-A for four time with an interval of seven days that is, on day 1, day 7, day 14 and day 21 with internal medication. In Group B only internal medication is given. The pre and post therapeutic subjective and objective criteria were recorded. All data were analyzed clinically as well as statistically. In both Group-A and Group-B. Jalaukavacharana has shown good result in reducing the symptoms of varicose eczema (Vicharchika)