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Multi-scale analysis for transport of fine settling particles through an ice-covered channel in a laminar flow condition

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International Journal of Sediment Research 2022年第6期37卷 794-808页

作者： Subham Dhar nanda Poddar B.S.Mazumder Kajal kumar Mondal Department of Mathematics Cooch Behar Panchanan Barma University Physics and Applied Mathematics Unit Indian Statistical Institute Department of Civil Engineering Indian Institute of Technology Bombay

The current research deals with the dispersion of fine settling particles in a fluid flowing through an icecovered channel under the laminar flow condition. An analytical solution of the two-dimensional convection-diffusion equation, based on the multi-scale homogenization technique, is obtained. To validate the current study, analytical results for the dispersion coefficient are compared with the available earlier research work. Moreover, the proposed analytical solutions for mean concentration distributions of the tracers are compared with the numerical results obtained from the finite difference technique. From the industrial and environmental points of view, the vertical concentration distribution provides a very significant information. The downstream evolution of the concentration distribution also is shown for typical time periods at different values of the settling velocity. The approach to the vertical uniformity shows that it is too slow a process in comparison to that of longitudinal normality. It was found that settling velocities of particles disturb the vertical uniformity and the centroid of the solute cloud rises due to the increase in settling velocity. Results illustrate that in the downstream direction, the vertical concentration distribution increases near the bed surface and it decreases in the proximity of the ice-covered surface of the channel with the increase of settling velocity, but the mean concentration of the solute increases. The current study may play an important role to understand the mechanism of the sedimentation process in a closed channel system.

关键词： Sediment transport Dispersion Ice-covered channel Vertical uniformity Multi-scale analysis

Extensional collapse of the Gondwana orogen: Evidence from Cambrian mafic magmatism in the Trivandrum Block, southern India

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Geoscience Frontiers 2019年第1期10卷 263-284页

作者： Qiong-Yan Yang Sohini Ganguly E.Shaji Yunpeng Dong V.nanda-kumar School of Earth Science and Resources China University of Geosciences Department of Earth Science Goa University Department of Geology University of Kerala State Key Laboratory of Continental Dynamics Department of Geology Northwest University National Center for Earth Science Studies Akkulam Trivandrum India

The assembly of Late Neoproterozoice Cambrian supercontinent Gondwana involved prolonged subduction and accretion generating arc magmatic and accretionary complexes, culminating in collision and formation of high grade metamorphic orogens. Here we report evidence for mafic magmatism associated with post-collisional extension from a suite of gabbroic rocks in the Trivandrum Block of southern Indian Gondwana fragment. Our petrological and geochemical data on these gabbroic suite show that they are analogous to high Fe tholeiitic basalts with evolution of the parental melts dominantly controlled by fractional crystallization. They display enrichment of LILE and LREE and depletion of HFSE with negative anomalies at Zre Hf and Ti corresponding to subduction zone magmatic regime. The tectonic affinity of the gabbros coupled with their geochemical features endorse a heterogeneous mantle source with collective melt contributions from sub-slab asthenospheric mantle upwelling through slab break-off and arc-related metasomatized mantle wedge, with magma emplacement in subduction to post-collisional intraplate settings. The high Nb contents and positive Nbe Ta anomalies of the rocks are attributed to inflow of asthenospheric melts containing ancient recycled subducted slab components and/or fusion of subducted slab materials owing to upwelling of hot asthenosphere. Zircon grains from the gabbros show magmatic crystallization texture with low U and Pb content. The LA-ICPMS analyses show ^(206) Pb/^(238) U mean ages in the range of 507-494 Ma suggesting Cambrian mafic magmatism. The post-collisional mafic magmatism identified in our study provides new insights into mantle dynamics during the waning stage of the birth of a supercontinent.

关键词： Mafic dykes Geochemistry Zircon Ue Pb geochronology Post-collisional extension Gondwana supercontinent

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Biochemical synthesis of silver nanoprticles using filamentous fungi Penicillium decumbens (MTCC-2494) and its efficacy against A-549 lung cancer cell line

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Chinese Journal of Natural Medicines 2016年第8期14卷 615-620页

作者： Shahnaz Majeed Mohd Syafiq bin Abdullah Gouri kumar Dash Mohammed Tahir Ansari Anima nanda Faculty of Pharmacy and Health Universiti Kuala Lumpur Royal college of Medicine Ipoh Perak Malaysia 30450 Faculty of Bioscience and chemical Engineering Sathyabama University Rajiv Gandhi Salai Chennai 600119 India

Biosynthesis of silver and other metallic nanoparticles is one of the emerging research area in the field of science and technology due to their potentiality, especially in the field of nano-biotechnology and biomedical sciences in order to develop nanomedicine. In our present study, Penicillium decumbens(MTCC-2494) was brought from Institute of Microbial Technology(IMTECH) Chandigarh and employed for extracellular biological synthesis of silver nanoparticles. Ag-NPs formation was appeared with a dark brown color inside the conical flask. Characterization of Ag-NPs were done by UV-Spectrophotometric analysis which showed absorption peak at 430 nm determines the presence of nanoparticles, Fourier transform infrared(FT-IR) spectroscopic analysis, showed amines and amides are the possible proteins involved in the stabilization of nanoparticles as capping agent. Atomic force Microscopy(AFM) confirmed the particle are spherical, size was around 30 to 60 nm and also the roughness of nanoparticles. Field emission scanning electron microscopy(FE-SEM) showed the topology of the nanoparticles and were spherical in shape. The biosynthesis process was found fast, ecofriendly and cost effective. Nano-silver particle was found to have a broad antimicrobial activity and also it showed good enhancement of antimicrobial activity of Carbenicillin, Piperacillin, Cefixime, Amoxicillin, Ofloxacin and Sparfloxacin in a synergistic mode. These Ag-NPs showed good anti-cancer activity at 80 μg·m L^(-1) upon 24 hours of incubation and toxicity increases upon 48 hours of incubation against A-549 human lung cancer cell line and the synergistic formulation of the antibiotic with the synthesized nanoparticles was found more effective against the pathogenic bacteria studied.

关键词： Silver nanoparticles Penicillium decumbens(MTCC-2494) Antibacterial Anti-cancer

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Preoperative Serum Albumin Levels and Postoperative Acute Kidney Injury in Off-Pump Coronary Artery Bypass Surgery: A Single-Center Study in Bangladesh

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World Journal of Cardiovascular Surgery 2024年第8期14卷 131-144页

作者： Ahmad Pear Salahuddin Md. Abir Tazim Chowdhury Munama Magdum Dewan Iftakher Reza Chowdhury Nittya nanda Pal Md. Nahedul Morshed Md. Zafar-Al-Nimari Latifa Nasrin Farooque Ahmed Department of Cardiac Surgery National Heart Foundation Hospital and Research Institute (NHFH&RI) Dhaka Bangladesh Department of Cardiothoracic and Vascular Surgery Evercare Hospital Dhaka Dhaka Bangladesh National Institute of Preventive and Social Medicine Dhaka Bangladesh Mother and Child Welfare Center Cumilla Bangladesh

Background: Serum albumin, a vital plasma protein, helps maintain intravascular colloidal osmotic pressure, cardiac output, and renal function. Low preoperative serum albumin is linked to poor outcomes, including acute kidney injury (AKI), after off-pump coronary artery bypass (OPCAB) surgery. This study aimed to assess the relationship between preoperative serum albumin levels and early postoperative renal injury. Methods: This prospective comparative cross-sectional study was conducted from August 2019 to February 2021 at the National Heart Foundation Hospital & Research Institute, Bangladesh. It included 160 adult patients with normal preoperative renal function undergoing OPCAB. Patients were divided into two groups: Group A (serum albumin ≥ 4.0 gm/dl) and Group B (serum albumin Results: Preoperative serum albumin was significantly different between groups (Group A: 4.21 ± 0.05 gm/dl, Group B: 3.69 ± 0.04 gm/dl, p = 0.028). Group B had a higher incidence of hypertension (71.25% vs. 51.25%, p st and 3rd postoperative days were higher in Group B (p th day. Postoperative AKI occurred in 18.75% of Group A and 36.25% of Group B. Multivariate regression indicated that low preoperative serum albumin is an independent risk factor for postoperative AKI (p = 0.012, OR = 1.815, CI: 0.675 - 1.162). Conclusion: Preoperative serum albumin level is a valuable predictor of postoperative renal function. Ensuring high normal serum albumin levels before surgery can help minimize the risk of postoperative AKI.

关键词： Serum Albumin Acute Kidney Injury (AKI) Off-Pump Coronary Artery Bypass Surgery Bangladesh

A Novel Optimizer in Deep Neural Network for Diabetic Retinopathy Classification

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Computer Systems Science & Engineering 2022年第12期43卷 1099-1110页

作者： Pranamita nanda N.Duraipandian Department of Computer Science and Engineering Velammal Institute of TechnologyChennai601204TamilnaduIndia Department of Computer Science and Engineering Saveetha Engineering CollegeChennai602105TamilnaduIndia

In severe cases, diabetic retinopathy can lead to blindness. For decades,automatic classification of diabetic retinopathy images has been a challenge. Medical image processing has benefited from advances in deep learning systems. Toenhance the accuracy of image classification driven by Convolutional Neural Network (CNN), balanced dataset is generated by data augmentation method followed by an optimized algorithm. Deep neural networks (DNN) are frequentlyoptimized using gradient (GD) based techniques. Vanishing gradient is the maindrawback of GD algorithms. In this paper, we suggest an innovative algorithm, tosolve the above problem, Hypergradient Descent learning rate based Quasi hyperbolic (HDQH) gradient descent to optimize the weights and biases. The algorithms only use first order gradients, which reduces computation time andstorage space requirements. The algorithms do not require more tuning of thelearning rates as the learning rate tunes itself by means of gradients. We presentempirical evaluation of our algorithm on two public retinal image datasets such asMessidor and DDR by using Resnet18 and Inception V3 architectures. The findings of the experiment show that the efficiency and accuracy of our algorithm outperforms the other cutting-edge algorithms. HDQHAdam shows the highestaccuracy of 97.5 on Resnet18 and 95.7 on Inception V3 models respectively.

关键词： CNN diabetic retinopathy data augmentation gradient descent deep learning optimization

Biomineralized and chemically synthesized magnetic nanoparticles:A contrast

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Frontiers of Materials Science 2020年第4期14卷 387-401页

作者： Tanya nanda Ankita RATHORE Deepika SHARMA Present adress:School of Biological and Health Systems Engineering Ira A.Fulton Schools of EngineeringArizona State UniversityTempeAZ 85281USA Present address:Academy of Scientific and Innovative Research(AcSir) CSIR-National Institute of Science Communication and Information Resources(NISCAIR)New Delhi 110067India Institute of Nano Science and Technology Habitat CentreSector 64Mohali 160062India

Magnetic nanoparticles(MNPS)have widely been synthesized through chemical processes for biomedical applications over the past few ***,a new class of MNPs,known as bacterial magnetosomes,has been isolated from magnetotactic bacteria,a natural *** magnetosomes are magnetite or greigite nanocrystals which are biomineralized in the bacterial cell and provide magnet-like properties to *** to MNPs,bacterial magnetosomes are biocompatible,lower in toxicity,and can be easily cleared from the body due to the presence of a phospholipid bilayer around *** also do not demonstrate aggregation,which makes them highly *** this review,we have provided an in-depth comparative account of bacterial magnetosomes and chemically synthesized MNPs in terms of their synthesis,properties,and biomedical *** addition,we have also provided a contrast on how magnetosomes might have the potential to successfully substitute synthetic MNPs in therapeutic and imaging applications.

关键词： bacterial magnetosomes magnetic nanoparticles iron nanoparticles magnetotactic bacteria magnetosomes

Color and Texture Segmentation Using an Unified MRF Model

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Journal of Computer and Communications 2022年第6期10卷 139-164页

作者： Sucheta Panda Pradipta kumar nanda Department of Computer Application VSSUT Burla India Department of Electronics and Communication Engineering Siksha O Anusandhan Deemed to be University Bhubaneswar India

The color image segmentation problem has two main issues to be solved. The proper choice of a color model and the choice of an appropriate image model are the key issues in color image segmentation. In this work, Ohta (I1, I2, I3) is taken as the color model and different variants of Markov Random Field (MRF) models are proposed. In this regard, a Compound Markov Random Field (COMRF) model is porposed to take care of inter-color-plane and intra-color-plane interactions as well. In continuation to this model, a Constrained Compound Markov Random Field Model (CCOMRF) has been proposed to model the color images. The color image segmentation problem has been formulated in an unsupervised framework. The performance of the above proposed models has been compared with the standard MRF model and some of the state-of-the-art methods, and found to exhibit improved performance.

关键词： Color Image Color Model Image Segmentation Simulated Annealing MRF Model

Artificial intelligence powered glucose monitoring and controlling system:Pumping module

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World Journal of Experimental Medicine 2024年第1期14卷 100-112页

作者： Sravani Medanki Nikhil Dommati Hema Harshitha Bodapati Venkata Naga Sai Kowsik Katru Gollapalli Moses Abhishek Komaraju nanda Sai Donepudi Dhanya Yalamanchili Jasti Sateesh Pratap Turimerla Department of Electronics and Communication Engineering Velagapudi Ramakrishna Siddhartha Engineering CollegeVijayawada 520007Andhra PradeshIndia Department of General Medicine Siddhartha Government Medical CollegeVijayawada 520008Andhra PradeshIndia

BACKGROUND Diabetes,a globally escalating health concern,necessitates innovative solutions for efficient detection and *** glucose control is an essential aspect of managing diabetes and finding the most effective ways to control *** latest findings suggest that a basal insulin administration rate and a single,highconcentration injection before a meal may not be sufficient to maintain healthy blood glucose *** the basal insulin rate treatment can stabilize blood glucose levels over the long term,it may not be enough to bring the levels below the post-meal limit after 60 *** short-term impacts of meals can be greatly reduced by high-concentration injections,which can help stabilize blood glucose ***,they cannot provide long-term stability to satisfy the postmeal or pre-meal ***,proportional-integral-derivative(PID)control with basal dose maintains the blood glucose levels within the range for a longer *** To develop a closed-loop electronic system to pump required insulin into the patient's body automatically in synchronization with glucose sensor *** The proposed system integrates a glucose sensor,decision unit,and pumping module to specifically address the pumping of insulin and enhance system *** as the intelligence hub,the decision unit analyzes data from the glucose sensor to determine the optimal insulin dosage,guided by a pre-existing glucose and insulin level *** artificial intelligence detection block processes this information,providing decision instructions to the pumping *** with communication antennas,the glucose sensor and micropump operate in a feedback loop,creating a closed-loop system that eliminates the need for manual *** The incorporation of a PID controller to assess and regulate blood glucose and insulin levels in individuals with diabetes introduces a sophisticated and dynamic element to diabetes ***

关键词： Diabetes Hyperglycemia Insulin Micropump Closed loop systems Artificial intelligence automation

Geochemistry of a paleosol horizon at the base of the Sausar Group,central India： Implications on atmospheric conditions at the Archeane Paleoproterozoic boundary

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Geoscience Frontiers 2016年第5期7卷 759-773页

作者： Sarada P.Mohanty Sangitsarita nanda Department of Applied Geology. Indian School of Mines Dhanbad 826004 India

A paleosol horizon is described from the contact of the Sausar Group（w2400 Ma） and its basement（Tirodi Gneiss; 〉2500 Ma） in Central India. Physical evidence of pedogenesis is marked by the development of stress corrosion cracks, soil peds, corestone weathering and nodular rocks. XRD and SEM-EDX data indicate the presence of siderite, ankerite, uraninite, chlorite, alumino-silicate minerals, ilmenite,rutile and magnetite, in addition to quartz, feldspar and mica. The chemical index of alteration, the plagioclase index of alteration, and the chemical index of weathering show an increasing trend from parent rock to the paleosol and indicate a moderate trend of weathering. The A-CN-K plot indicates loss of feldspars, enrichment in Al2O3 and formation of illite. Different major element ratios indicate baseloss through hydrolysis, clay formation, leaching of some elements, and more precipitation with good surface drainage. The paleosol is depleted in HREE in comparison to the parent rock indicating high fluid-rock interaction during weathering. The paleosol samples show flat Ce and Eu anomalies, low SREE, and high（La/Yb）N, indicative of a reducing environment of formation. Reducing condition can also be inferred from the concentration of elements such as V, Co, Cu, Pb, and Zn in the paleosol profile. Although enriched in Fe and Mg, the overall geochemical patterns of the paleosol indicate oxygen deficient conditions in the atmosphere and development by weathering and leaching processes associated with high precipitation and good surface drainage at the time of development of this paleosol during the Archeane Paleoproterozoic transition.

关键词： Paleosol Anoxic weathering Great oxidation event Paleoproterozoic Sausar Group

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