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Infectious Disease Modelling 2022年第1期7卷 199-211页

作者： David Nino-Torres Andres Ríos-Gutierrez Viswanathan Arunachalam Comfort Ohajunwa padmanabhan seshaiyer Department of Statistics Universidad Nacional de ColombiaBogotaColombia George Mason University FairfaxVAUSA

In this paper,a stochastic epidemiological model is presented as an extension of a compartmental SEIR model with random perturbations to analyze the dynamics of the COVID-19 pandemic in the city of Bogota D.C.,*** model incorporates thespread of COVID-19 impacted by social behaviors in the population and allows for projecting the number of infected,recovered,and deceased individuals considering the mitigation measures,namely confinement and partial relaxed ***,the role of randomness using the concept of Brownian motion is emphasized to explain the behavior of the *** experiments for the stochastic model with random perturbations were performed,and the model is validated through numerical simulations for actual data from Bogota D.C.

关键词： Epidemic spread SARS-CoV-2 Compartmental modeling Stochastic perturbations Parameter estimation

Enhancing Groundwater Quality through Computational Modeling and Simulation to Optimize Transport and Interaction Parameters in Porous Media

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Journal of Water Resource and Protection 2015年第5期7卷 398-409页

作者： Akhil Waghmare padmanabhan seshaiyer Thomas Jefferson High School for Science and Technology Alexandria VA USA Mathematical Sciences George Mason University Fairfax VA USA

There is a shortage of high quality drinking water caused by the introduction of contaminants into aquifers from various sources including industrial processes and uncontrolled sewage. Studies have shown that colloids, collections of nanoparticles, have the potential to remediate polluted groundwater. For such applications of nanoparticles, it is important to understand the movement of colloids. This study aims to enhance the previously developed MNM1D (Micro- and Nanoparticle transport Model in porous media in one-dimensional geometry) by making more realistic assumptions about physical properties of the groundwater-porous medium system by accounting for a non-constant flow velocity and the presence of electromagnetic interactions. This was accomplished by coupling the original model with the Darcy-Forchheimer fluid model, which is specific to transport in porous media, coupled with electromagnetic effects. The resulting model also accounts for attachment and detachment phenomena, both of the linear and Langmuirian type, as well as changes to hydrochemical parameters such as maximum colloidal particle concentration in the porous medium. The system of partial-differential equations that make up the model was solved using an implicit finite-difference discretization along with the iterative Newton’s method. A parameter estimation study was also conducted to quantify parameters of interest. This more realistic model of colloid transport in porous media will contribute to the production of a more efficient method to counteract contaminants in groundwater and ultimately increase availability of clean drinking water.

关键词： Water Quality Computational Modeling Colloid Transport

Performance assessment of prefabricated vertical drains in mitigating soil reliquefaction subjected to repeated seismic events using shaking table experiments

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 411-427页

作者： Gowtham padmanabhan Ganesh Kumar SHANMUGAM Department of Earthquake Engineering Indian Institute of Technology RoorkeeUttarakhand 247667India Geotechnical Engineering Division CSIR-Central Building Research Institute Academy of Scientific and Innovative Research(AcSIR)Uttarakhand 247667India

The use of prefabricated vertical drains(PVD)in liquefiable deposits is gaining attention due to enhanced ***,investigations on PVD in mitigating re-liquefaction during repeated shaking events are not *** study performed a series of shaking table experiments on untreated and PVD-treated specimens prepared with 40%and 60%relative *** sinusoidal loading was applied with an incremental peak acceleration of 0.1g,0.2g,0.3g,and 0.4g,at 5 Hz shaking frequency with 40 s *** performance of treated ground was evaluated based on the generation and dissipation of excess pore water pressure(EPWP),induced sand densification,subsidence,and cyclic stress *** addition,the strain accumulated in fresh and exhumed PVD was investigated using geotextile tensile testing apparatus aided with digital image *** evidence of pore pressure was reported up to 0.2g peak acceleration for 40%and 60%relative density *** continuous occurrence of soil densification and drainage medium restrained and delayed the generation of EPWP and expedited the dissipation *** study demonstrates PVD can mitigate re-liquefaction,without suffering from deterioration,when subjected to medium to high intense repeated shaking events.

关键词： prefabricated vertical drains drainage re-liquefaction shaking table digital image correlation

Hepatocellular carcinoma presenting as an extrahepatic mass:A case report and review of literature

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2241-2252页

作者： Wei Kelly Wu Krutika Patel Chandrasekhar padmanabhan Kamran Idrees Department of Surgery Vanderbilt University Medical CenterNashvilleTN 37232United States Department of Pathology Microbiology and ImmunologyVanderbilt University Medical CenterNashvilleTN 37232United States Division of Surgical Oncology and Endocrine Surgery Department of SurgeryVanderbilt University Medical CenterNashvilleTN 37232United States

BACKGROUND Hepatocellular carcinoma(HCC)is a primary liver tumor generally diagnosed based on radiographic *** disease is typically associated with increased tumor diameter,multifocality,and vascular *** report a case of a patient who presented with extrahepatic HCC metastasis to a portocaval lymph node with occult hepatic primary on computed tomography(CT).We review the literature for cases of extrahepatic HCC presentation without known hepatic lesions and discuss strategies to differentiate between metastatic and ectopic *** SUMMARY A 67-year-old male with remotely treated hepatis C was referred for evaluation of an enlarging portocaval,mixed cystic-solid *** CT evaluations demonstrated steatosis,but no cirrhosis or liver *** ultrasound demonstrated a normal-appearing pancreas,biliary tree,and *** needle aspiration yielded atypical *** differential diagnosis included duodenal or pancreatic cyst,lymphoproliferative cyst,stromal or mesenchymal lesions,nodal involvement from gastrointestinal or hematologic malignancy,or duodenal gastrointestinal stromal *** review by a multidisciplinary tumor board,the patient underwent open surgical resection of a 5.2 cm×5.5 cm retroperitoneal mass with pathology consistent with moderately-differentiated *** resonance imaging(MRI)subsequently demonstrated a 1.2 cm segment VIII hepatic lesion with late arterial enhancement,fatty sparing,and intrinsic T1 *** fetoprotein was 23.3 ng/*** patient was diagnosed with HCC with portocaval nodal ***:We surveyed the literature for HCC presenting as extrahepatic masses without history of concurrent or prior intrahepatic *** identified 18 cases of extrahepatic HCC ultimately found to represent metastatic lesions,and 30 cases of extrahepatic HCC found to be primary,ectopic *** Hepatocellular carcinoma can seldomly present with extrahepatic metastasis in the setting of

关键词： Extrahepatic Metastasis Portocaval Lymph node Case report

Nitrosamines crisis in pharmaceuticals-Insights on toxicological implications,root causes and risk assessment:A systematic review

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Journal of Pharmaceutical Analysis 2024年第5期14卷 639-652页

作者： Hemanth P.R.Vikram Tegginamath Pramod Kumar Gunjan Kumar Narasimha M.Beeraka Rajashree Deka Sheik Mohammed Suhail Sandeep Jat Namitha Bannimath Gayatiri padmanabhan Ravandur S.Chandan Pramod Kumar Bannimath Gurupadayya Department of Pharmaceutical Chemistry JSS College of Pharmacy MysuruJSS Academy of Higher Education and Research(JSSAHER)Mysuru570015India Xenone Healthcare Pvt.Ltd. New Delhi110076India Department of Pharmaceutics JSS College of Pharmacy MysuruJSS Academy of Higher Education and Research(JSSAHER)Mysuru570015India Department of Human Anatomy I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow119991Russian Federation Department of Pharmacology Raghavendra Institute of Pharmaceutical Education and Research(RIPER)Ananthapuramu515721India Herman B.Wells Center for Pediatric Research Department of PediatricsIndiana University School of MedicineIndianapolisIN46202USA Animal Physiology and Biochemistry Laboratory Department of ZoologyGauhati UniversityGuwahati781014India Department of Pharmacology JSS College of Pharmacy MysuruJSS Academy of Higher Education and Research(JSSAHER)Mysuru570015India Department of Pharmaceutical Analysis National Institute of Pharmaceutical Education and Research(NIPER)-GuwahatiChangsari781101India Department of Pharmacology University of GalwayGalwayH91 TK33Ireland

The presence of N-nitroso compounds,particularly N-nitrosamines,in pharmaceutical products has raised global safety concerns due to their significant genotoxic and mutagenic *** systematic review investigates their toxicity in active pharmaceutical ingredients(APIs),drug products,and pharmaceutical excipients,along with novel analytical strategies for detection,root cause analysis,reformulation strategies,and regulatory guidelines for *** review emphasizes the molecular toxicity of N-nitroso compounds,focusing on genotoxic,mutagenic,carcinogenic,and other physiological ***,it addresses the ongoing nitrosamine crisis,the development of nitrosamine-free products,and the importance of sensitive detection methods and precise risk *** comprehensive overview will aid molecular biologists,analytical scientists,formulation scientists in research and development sector,and researchers involved in management of nitrosamine-induced toxicity and promoting safer pharmaceutical products.

关键词： Carcinogenicity Genotoxicity Mutagenicity Molecular toxicity Nitrosamine impurities Nitrosamine drug substance-related impurities

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大男孩的玩具

中学生英语 2024年第25期 20-23页

作者： Chitra padmanabhan 李明娟

罗内特·苏布兰马尼安七岁了，他是班上最高的学生。这让他感到非常自豪。但是当他想起小时候经常做的一些事情时，他感到有点害羞。他希望他的母亲不要一遍又一遍地给她的朋友们讲那些往事。上周他母亲的老校友来看过她，（毕业）10年...

罗内特·苏布兰马尼安七岁了，他是班上最高的学生。这让他感到非常自豪。但是当他想起小时候经常做的一些事情时，他感到有点害羞。他希望他的母亲不要一遍又一遍地给她的朋友们讲那些往事。上周他母亲的老校友来看过她，（毕业）10年后她们又见面了。罗内特刚从学校回来，这时他听到妈妈说:“你知道我的罗内特小时候经常做什么吗？他过去认为一切事物和每个人都是苏布兰马尼安家庭的一部分。所以他称冰箱为‘苏布兰马尼安家的冰箱’。他会把蜷缩在我家门口门垫上的小狗叫做‘苏布兰马尼安家的小狗’。”罗内特听到母亲的朋友在笑，他就跑出了家——午饭都没吃。“我希望妈妈不要再做这事情了。”这话他说了上千次了。

关键词：

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水果之王——芒果

中学生英语 2024年第9期 22-25页

作者： Chitra padmanabhan 李明娟(选译) 不详

这是一种一年四季都是绿色的树。但它在盛夏结果实。天气越热,果实越甜。而且我们人类似乎吃不腻这种美味的水果,因为全世界有将近1000个品种的“水果之王”来取悦我们的舌头和眼睛。

关键词：水果之王芒果舌头盛夏眼睛

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Corrigendum to“Nitrosamines crisis in pharmaceuticals-Insights on toxicological implications,root causes and risk assessment:A systematic review”[***.14(2024)100919]

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Journal of Pharmaceutical Analysis 2024年第6期14卷 934-936页

Original statement in the Section 2:*** search Our primary screening of 180 articles yielded the relevant data for this *** selection A total of 180 articles spanning from 1960 to the present day,including original research,reviews,case reports and studies reporting nitrosamine impurities above the no-observed-adverse-effect levels(NOAEL)established by regulatory agencies,were initially *** the primary screening,we considered factors such as relevance,publication date,access to the full article text,and content.

关键词： statement initially spanning

Experimental studies on liquefaction and reliquefaction potential of saturated ground subjected to repeated incremental acceleration loading with varying shaking duration

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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 909-920页

作者： Gowtham padmanabhan Ganesh Kumar Shanmugam Department of Earthquake Engineering Indian Institute of Technology RoorkeeRoorkeeUttarakhand 247667India Geotechnical Engineering Division CSIR-Central Building Research InstituteAcademy of Scientific and Innovative Research(AcSIR)RoorkeeUttarakhand 247667India

Past research has focused on the factors that influence liquefaction under normal shaking ***,studies on parameters that influence the reliquefaction potential of saturated deposits during repeated shaking events are *** this study,an attempt has been made to examine the influence of acceleration amplitude and shaking duration on liquefaction and reliquefaction potential under repeated shaking conditions is conducted.1-g uni-axial shaking table experiments were performed on saturated ground prepared with 40%and 60%relative *** prepared ground was subjected to alternate longer and shorter shaking durations(40 and 20 s)of repeated incremental 0.1 g,0.2 g,0.3 g and 0.4 g acceleration loading,*** variation in density,excess pore water pressure(EPWP),cyclic resistance ratio(CRR)and surface settlement were *** results showed that due to repeated incremental shaking events,reliquefaction was observed on the prepared *** longer shaking duration,the post-liquefied soil showed density improvement with improved soil ***,the application of shorter duration loading followed by longer shaking reduced the beneficial effect of density improvement by disturbing the densified *** to this,the ground was found to be more susceptible to reliquefaction in the subsequent incremental longer shaking event.

关键词： 1g–shaking table reliquefaction acceleration amplitude shaking duration relative density

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Emergent perspective of gravity and dark energy

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Research in Astronomy and Astrophysics 2012年第8期12卷 891-916页

作者： T.padmanabhan IUCAA Pune University CampusGaneshkhind

There is sufficient amount of internal evidence in the nature of gravitational theories to indicate that gravity is an emergent phenomenon like, e.g, elasticity. Such an emergent nature is most apparent in the structure of gravitational dynamics. It is, however, possible to go beyond the field equations and study the space itseff as emer- gent in a well-defined manner in （and possibly only in） the context of cosmology. In the first part of this review, I describe various pieces of evidence which show that gravitational field equations are emergent. In the second part, I describe a novel way of studying cosmology in which I interpret the expansion of the universe as equivalent to the emergence of space itself. In such an approach, the dynamics evolves towards a state of holographic equipartition, characterized by an equality in the number of bulk and surface degrees of freedom in a region bounded by the Hubble radius. This prin- ciple correctly reproduces the standard evolution of a Friedmann universe. Further, （a） it demands the existence of an early inflationary phase as well as late time accelera- tion for its successful implementation and （b） allows us to link the value of late time cosmological constant to the e-folding factor during inflation.

关键词： cosmology: theory -- cosmology: cosmological parameters -- emergentgravity -- holographic principle

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