检索结果-南通市图书馆

Determination of the time of refractive stability after uneventful phacoemulsification in Indian eyes

在线全文

学校读者我要写书评

暂无评论

World Journal of Experimental Medicine 2024年第2期14卷 89-96页

作者： Ashok kumar Nanda Bijnya Birajita Panda Asish Swain logesh Balakrishnan Department of Ophthalmology Kar Vision Eye HospitalBhubaneswar 751013OdishaIndia Department of Ophthalmology All India Institute of Medical SciencesBhubaneswar 751019OdishaIndia Department of Optometry Kar Vision Eye HospitalBhubaneswar 751013OdishaIndia Department of Statistics Apollo HospitalsChennai 823104India

BACKGROUND Knowledge about refractive stabilization and the accuracy of postoperative refractive error measurements are crucial for improved patient outcomes after *** guidelines typically recommend waiting 4-6 wk before prescribing corrective *** research focused on identifying factors that influence refractive errors in the early stages of post-cataract surgery,thus contributing to the existing literature on this *** To investigate the time required for refraction stability after uneventful phacoemulsification *** We compared the variation and statistical significance of the difference in spherical,cylindrical components,and the spherical equivalent between the 1-and 6-wk follow-up period in a group of 257 eyes that underwent uneventful phacoemulsification with foldable intraocular lens implantation,all performed by a single experienced *** Wilcoxon-Signed Rank Test was utilized to assess the magnitude of the change and determine its statistical *** refractive stability was defined as the point at which the change in spherical equivalent was within±0.5 dioptres for two consecutive *** The average age of the patients was 64.9±8.9 *** differences observed in both the visits in spherical power(0.1±0.2),cylinder power(0.3±0.4),and spherical equivalent(0.2±0.2)were minimal and not statistically *** majority of eyes(93.4%)achieved refractive stability within 6 wk after the *** cylindrical power differed between age groups at the 6th wk post-operative and the difference was statistically significant(P value 0.013).There were no significant differences in refractive stability when considering sex and axial *** Phacoemulsification with foldable intraocular lens implantation results in no significant changes in refraction for the majority of cases during the 6-wk follow-up ***,a spectacle prescription can be given at the completion of 1 wk.

关键词： Cataract surgery Phacoemulsification Refraction stability Visual acuity Spherical equivalent

Honey vesicle-like nanoparticles protect aged liver from non-alcoholic steatohepatitis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Pharmaceutica Sinica B 2024年第8期14卷 3661-3679页

作者： Baolong Liu Phuong Linh Nguyen Han Yu Xingzhi Li Huiren Wang Tram Gia Bao Nguyen Prakash kumar Sahoo Meghna Sur Jay Reddy Sarah Sillman Stephen D.Kachman Bara Altartouri Guoqing Lu Sathish kumar natarajan Mahesh Pattabiraman Jiujiu Yu Department of Nutrition and Health Sciences University of Nebraska-LincolnLincolnNE 68583USA Shaanxi Key Laboratory of Molecular Biology for Agriculture College of Animal Science and TechnologyNorthwest A&F UniversityYangling 712100China Department of Nutrition Case Western Reserve UniversityClevelandOH 44106USA School of Veterinary Medicine and Biomedical Sciences University of Nebraska-LincolnLincolnNE 68583USA Department of Statistics University of Nebraska-LincolnLincolnNE 68583USA Center for Biotechnology University of Nebraska-LincolnLincolnNE 68588USA Department of Biology University of Nebraska OmahaOmahaNE 68182USA Department of Chemistry University of Nebraska-KearneyKearneyNE 68849USA

Non-alcoholic steatohepatitis(NASH),an advanced form of non-alcoholic fatty liver disease(NAFLD),has emerged as the leading cause of liver failure and related ***,no medication is specifically approved to treat NAFLD or *** we report that oral administration of honey vesiclelike nanoparticles(H-VLNs)to naturally aged mice protects the liver from NASH development.H-VLNs are dominantly taken up by Kupffer cells in the liver and suppress hepatic chronic inflammation and further development of fibrosis and nodule formation in aged *** their reported antiinflammasome function,H-VLNs are found to inhibit the transcriptional activities of C-JUN and nuclear factor-kappa B(NF-κB).MicroRNAs miR5119 and miR5108 and phenolic compound luteolin in H-VLNs are identified in suppressing both the C-JUN and NF-kB ***,oral intake of H-VLNs represents a promising new user-friendly modality to prevent the development of NASH.

关键词： Honey Extracellular vesicles Exosomes Nanoparticles microRNAs Aging Inflammation Non-alcoholic steatohepatitis

A FEniCS implementation of the phase field method for quasi-static brittle fracture

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2019年第2期13卷 380-396页

作者： HIRSHIKESH Sundararajan natarajan Ratna kumar ANNABATTULA Integrated Modeling and Simulation Lab Department of Mechanical EngineeringIndian Institute of Technology MadrasChennai- 600036India

In the recent years, the phase field method for simulating fracture problems has received considerable attention. This is due to the salient features of the method: 1) it can be incorporated into any conventional finite element software;2) has a scalar damage variable is used to represent the discontinuous surface implicitly and 3) the crack initiation and subsequent propagation and branching are treated with less complexity. Within this framework, the linear momentum equations are coupled with the diffusion type equation, which describes the evolution of the damage variable. The coupled nonlinear system of partial differential equations are solved in a 'staggered? approach. The present work discusses the implementation of the phase field method for brittle fracture within the open-source finite element software, FEniCS. The FEniCS provides a framework for the automated solutions of the partial differential equations. The details of the implementation which forms the core of the analysis are presented. The implementation is validated by solving a few benchmark problems and comparing the results with the open literature.

关键词： phase field method FEniCS brittle fracture crack propagation variational theory of fracture

Evolution of fracture permeability due to co-colloidal bacterial transport in a coupled fracture-skin-matrix system

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geoscience Frontiers 2012年第4期3卷 503-514页

作者： N.natarajan G.Suresh kumar EWRE Division Department of Civil EngineeringIndian Institute of TechnologyMadrasChennai 600036India Department of Ocean Engineering Indian Institute of TechnologyMadrasChennai 600036India

A numerical model is developed for investigating the evolution of fracture permeability in a coupled fracture-matrix system in the presence of fracture-skin with simultaneous colloidal and bacte- rial transport, by taking into account the effects of thermal stress and silica precipitation/dissolution, which is computed using linear reaction kinetics. The non-linear coupled equations are numerically modeled using the fully implicit finite difference method and a constant continuous source is adopted while modeling thermal, contaminant, colloidal and bacterial transport. Due to co-colloid bacterial trans- port under non-isothermal conditions, in a coupled fracture-skin-matrix system, the fracture apertures vary spatially, with a corresponding pressure variation for a constant discharge. A series of numerical experiments were conducted for analyzing the spatial variation of fracture aperture in response to the combined effects of thermal stress, silica precipitation/dissolution, and simultaneous colloidal and bacte- rial transport in the presence of the fracture-skin. The simulation results suggest that temperature and contaminant concentration of the mobile fluid within the fracture increases with reduction in initial frac- ture aperture. The pattern of variation followed by the fracture aperture is nearly the same in the presence and absence of bacterial transport but the magnitude of the fracture aperture is low under the influence of bacterial transport. The variation in the fracture aperture resulting from precipitation-dissolution and thermoelastic stress is significant when the fracture aperture is very low and reduces with increment in fracture aperture. The variation in fracture aperture and pressure remains the same for both undersaturated and supersaturated fluid entering the fracture due to the influence of bacterial transport at the inlet of the fracture.

关键词： Bacterial transport Colloidal transport Fracture permeability Fracture skin Precipitation-dissolution

Unsupported nanoporous palladium‐catalyzed chemoselective hydrogenation of quinolines:Heterolytic cleavage of H_2 molecule

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2018年第11期39卷 1746-1752页

作者： Ye Lu Yoshinori Yamamoto Abdulrahman I.Almansour natarajan Arumugam Raju Suresh kumar Ming Bao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116023LiaoningChina Department of Chemistry Graduate School of ScienceTohoku UniversitySendai 980‐8578Japan Research Organization of Science and Technology Ritsumeikan UniversityKusatsuShiga 525‐8577Japan Department of Chemistry College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

An efficient and highly chemoselective heterogeneous catalyst system for quinoline hydrogenation was developed using unsupported nanoporous palladium(PdNPore).The PdNPore‐catalyzed chemoselective hydrogenation of quinoline proceeded smoothly under mild reaction conditions(low H2 pressure and temperature)to yield 1,2,3,4‐tetrahydroquinolines(py‐THQs)in satisfactory to excellent *** synthetically useful functional groups,such as halogen,hydroxyl,formyl,ethoxycarbonyl,and aminocarbonyl groups,remained intact during the quinoline *** palladium was leached from PdNPore during the hydrogenation ***,the catalyst was easily recovered and reused without any loss of catalytic *** results of kinetic,deuterium‐hydrogen exchange,and deuterium‐labeling experiments indicated that the present hydrogenation involves heterolytic H2 splitting on the surface of the catalyst.

关键词： Nanoporous materials Palladium Quinoline Chemoselective hydrogenation Heterogeneous catalyst

Cytogenetic studies of chromium(Ⅲ) oxide nanoparticles on Allium cepa root tip cells

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2015年第12期27卷 150-157页

作者： Deepak kumar A.Rajeshwari Pradeep Singh Jadon Gouri Chaudhuri Anita Mukherjee natarajan Chandrasekaran Amitava Mukherjee Centre for Nanobiotechnology VIT University Centre of Advanced Study Department of BotanyUniversity of Calcutta

The current study evaluates the cytogenetic effects of chromium（Ⅲ） oxide nanoparticles on the root cells of Allium *** root tip cells of *** were treated with the aqueous dispersions of Cr2O3 nanoparticles（NPs） at five different concentrations（0.01,0.1,1,10,and 100 μg/m L） for 4 *** colloidal stability of the nanoparticle suspensions during the exposure period were ascertained by particle size *** 4 hr exposure to Cr2O3 NPs,a significant decrease in mitotic index（MI） from 35.56%（Control） to 35.26%（0.01 μg/m L）,34.64%（0.1 μg/m L）,32.73%（1 μg/m L）,29.6%（10 μg/m L） and 20.92%（100 μg/m L） was *** optical,fluorescence and confocal laser scanning microscopic analyses demonstrated specific chromosomal aberrations such as-chromosome stickiness,chromosome breaks,laggard chromosome,clumped chromosome,multipolar phases,nuclear notch,and nuclear bud at different exposure *** concentration-dependent internalization/bio-uptake of Cr2O3 NPs may have contributed to the enhanced production of anti oxidant enzyme,superoxide dismutase to counteract the oxidative stress,which in turn resulted in observed chromosomal aberrations and cytogenetic *** results suggest that *** root tip assay can be successfully applied for evaluating environmental risk of Cr2O3 NPs over a wide range of concentrations.

关键词： A.cepa Bio-uptake Chromosomal aberration C2O3 nanoparticles Mitotic index SOD

Effect of fracture-skin on virus transport in fractured porous media

在线全文

学校读者我要写书评

暂无评论

Geoscience Frontiers 2012年第6期3卷 893-900页

作者： N.natarajan G.Suresh kumar EWRE Division Department of Civil EngineeringIndian Institute of TechnologyMadrasChennai 36India Department of Ocean Engineering Indian Institute of TechnologyMadrasChennai 36India

A numerical model is developed for describing the transport of virus in a fracture-matrix coupled system with fracture-skin. An advective dispersive virus transport equation, including first- order sorption and inactivation constant is used for simulating the movement of viruses. Implicit finite-difference numerical technique is used to solve the coupled non-linear governing equations for the triple continuum model consisting of fracture, fracture-skin and the rock-matrix. A varying grid is adopted at the fracture and fracture-skin interface to capture the mass transfer. Sensitivity analysis was performed to investigate the effect of various properties of the fracture-skin as well as viruses on the virus concentration in the fractured formation with fracture-skin. Simulation results suggest that the virus concentration in the fracture decreases with increment in the fracture-skin porosity, fracture-skin diffu- sion coefficient, mass transfer coefficient, inactivation constant and sorption distribution coefficient, and with reduction in the fracture aperture.

关键词： Fracture-skin Virus transport Rock-matrix Fracture

sp^(2)碳用于3D打印技术综述:材料、性能和应用

在线全文

学校读者我要写书评

暂无评论

新型炭材料（中英文） 2022年第6期37卷 1046-1065页

作者： Satendra kumar Manoj Goswami Netrapal Singh Sathish natarajan Surender kumar Academy of Scientific and Innovative Research(AcSIR) Ghaziabad 201002India CSIR-Advanced Materials and Processes Research Institute(AMPRI) Bhopal 462026India

3D打印可以改变现有的生产方法,是第四次工程革命中的一项现代技术。它从成型原理上提出了分层制造、逐层叠加成型的新颖生产方法,从根本上简化了制造工艺,实现了大规模定制生产。然而,这一新技术仍存在许多问题。除了纯石墨烯外,sp^(2... 详细信息

3D打印可以改变现有的生产方法,是第四次工程革命中的一项现代技术。它从成型原理上提出了分层制造、逐层叠加成型的新颖生产方法,从根本上简化了制造工艺,实现了大规模定制生产。然而,这一新技术仍存在许多问题。除了纯石墨烯外,sp^(2)碳具有好的亲水性,3D打印难度较小。sp^(2)碳还可在3D打印中的各种阶段应用。纯石墨烯的疏水性使其难以在水系介质中打印和加工。毛细管油墨的发展使得纯石墨烯的3D打印成为可能。本文综述了sp^(2)碳的3D打印技术的最新进展。首先简要概述了3D打印技术,随后概述了sp^(2)碳的3D打印及其在各种方面的应用。最后,讨论了这一新领域的发展前景和机遇。

关键词： 3D打印技术 sp^(2)碳碳基复合材料应用

Carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacolborate catalyzed by palladium nanoparticles

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Catalysis 2018年第7期39卷 1258-1262页

作者： Jian Sun Jiasheng Wang Xiujuan Feng Yoshinori Yamamoto Abdulrahman I.Almansour natarajan Arumugam Raju Suresh kumar Ming Bao State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116023LiaoningChina School of Petroleum and Chemical Engineering Dalian University of TechnologyPanjin 124221Liaoning China Department of Chemistry Graduate School of Science Tohoku UniversitySendai 980-8578Japan Research Organization of Science and Technology Ritsumeikan UniversityKusatsuShiga 525-8577Japan Department of Chemistry College of Sciences King Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arobia

Palladium-catalyzed carboxylative Suzuki coupling reactions of benzyl chlorides with allyl pinacol-borate were successfully conducted in the absence of any extra ligand to produce β,γ-unsaturated esters in satisfactory to good yields. The carboxylative Suzuki coupling reaction proceeded smooth-ly under mild conditions in the presence of palladium nanoparticles generated in situ through the formation of a π-benzylpalladium chloride intermediate.

关键词： Palladium nanoparticles Carboxylative Suzuki coupling Carbon dioxide Benzyl chlorides Allyl pinacolborate