检索结果-南通市图书馆

Pattern dynamics of a reaction-diffusion predator-prey system with both refuge and harvesting

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Biomathematics 2021年第1期14卷 1-29页

作者： lakshmi Narayan Guin Sudipta Pal Santabrata Chakravarty Salih Djilali Department of Mathematics Visva-BharatiSantiniketan 731235West BengalIndia Department of Mathematics Universite Hassiba Benbouali de ChlefChlef 02000Algeria Laboratoire d’Analyse Non Linéaire et Mathématiques AppliquéesUniversitéde TlemcenTlemcenAlgeria

We are concerned with a reaction-diffusion predator–prey model under homogeneous Neumann boundary condition incorporating prey refuge(proportion of both the species)and harvesting of prey species in this *** for asymptotic stability(local and global)and bifurcation of the subsequent temporal model system are thoroughly analyzed around the unique positive interior equilibrium *** partial differential equation(PDE),the conditions of diffusion-driven instability and the Turing bifurcation region in two-parameter space are *** results around the unique interior feasible equilibrium point specify that the effect of refuge and harvesting cooperation is an important part of the control of spatial pattern formation of the species.A series of computer simulations reveal that the typical dynamics of population density variation are the formation of isolated groups within the Turing space,that is,spots,stripe-spot mixtures,labyrinthine,holes,stripe-hole mixtures and stripes ***,we discuss spatiotemporal dynamics of the system for a number of different momentous parameters via numerical simulations.

关键词： Two species reaction-diffusion system ratio-dependent functional response diffusion-driven instability pattern selection stationary patterns

Implications of turbulent shear on clay floc break-up along the Atlantic estuary(Bouregreg),Morocco

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Sediment Research 2022年第2期37卷 248-257页

作者： Krishnamoorthy lakshmi Ammal Priya Soufiane Haddout Joan Cecilia Catubig Casila Department of Civil Engineering TKM College of Engineering Department of Physics Faculty of Science Ibn Tofail University Land and Water Resources Division IABE CEAT University of the Philippines Los Ba?os

Water depth,salinity,current,and suspended sediment concentration(SSC) were measured along with the grain size distribution of bed sediment along an estuarine longitudinal *** floc size increased with increase in the percentage of clay and silt,while decreased with increase in the percentage of sand content of bed *** turbulent shear,G,had a direct effect on floc size with its value increasing with increase in G up to a G value of 15 s,while an inverse relation existed between floc size and G at higher G(C> 15 s).Further,higher turbulence enabled sand to get resuspended and cause additional shear leading to the break-up of *** attempt was made to modify G to account for the combined effect of water turbulence(C) and shear imparted by sand(C) and the impact of the modification of G on the predictability of floc size was evaluated.A new model was developed which explains floc size in terms of sediment concentration(C),salinity gradient(S),and G for different scenarios based on the value of *** analysis was done for observed floc size(FS) and predicted floc size using four approaches:(Ⅰ) FS β C~χ;(Ⅱ) FS α C~χS;(Ⅲ) FS α C~χSG~z for G 15 s; and(Ⅳ) FS α C~χSGfor G> 15 sand G=G+G,where x,y,and z are determined by *** was observed that the predictability of the floc size improved when the turbulence was modified to account for shear imparted by sand so that the coefficient of determination was increased from 0.78 for model Ⅲ to 0.89 for model Ⅳ.Further,the settling velocity was expressed as a function of suspended sediment concentration,turbulent shear,and salinity *** predictability of settling velocity was improved(R~2 increased from 0.77 to 0.86) when the additional turbulence created by sand was incorporated in the non-dimensional empirical *** study highlights the influence of sand in causing the break-up of flocs and suggests that for turbulence shear values high enough to resuspend

关键词： Floc size Settling velocity Turbulent shear Non-cohesive sediment Bouregreg estuary Morocco

Impact of predation in the spread of an infectious disease with time fractional derivative and social behavior

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Modeling, Simulation, and Scientific Computing 2021年第4期12卷 92-119页

作者： Soufiane Bentout Behzad Ghanbari Salih Djilali lakshmi Narayan Guin Department of Mathematics and Informatics Belhadj Bouchaib University Center of Ain Temouchent BP 284 RP 46000Algeria Laboratoire d’Analyse Non Linaire et Mathmatiques Appliques Universit de Tlemcen TlemcenAlgeria Department of Engineering Science Kermanshah University of Technology KermanshahIran Department of Biomedical Engineering Faculty of Engineering and Naturel Sciences Bah¸ce¸sehir University 34349 IstanbulTurkey Faculty of Exact and Computer Sciences Mathematic Department Hassiba Benbouali University ChlefAlgeria Department of Mathematics Visva-Bharati Santiniketan-731235 West BengalIndia

The main purpose of this paper is to explore the influence of predation on the spread of a disease developed in the prey population where we assume that the prey has a social *** memory of the prey and the predator measured by the time fractional derivative plays a crucial role in modeling the dynamical response in a predator–prey *** memory can be modeled to articulate the involvement of interacting species by the presence of the time fractional derivative in the considered *** the purpose of studying the complex dynamics generated by the presence of infection and the time-fractional-derivative we split our study into two cases. The first one is devotedto study the effect of a non-selective hunting on the spread of the disease, where the localstability of the equilibria is investigated. Further the backward bifurcation is obtainedconcerning basic reproduction rate of the infection. The second case is for explaining theimpact of selecting the weakest infected prey on the edge of the herd by a predator onthe prevalence of the infection, where the local behavior is scrutinized. Moreover, for thegraphical representation part, a numerical simulation scheme has been achieved usingthe Caputo fractional derivative operator.

关键词： Predator–prey model herd behavior fractional derivative numerical schema backward bifurcation eco-epidemiological model

Bacteria as indicators for finding oil and gas reservoirs:A case study of the Bikaner-Nagaur Basin,Rajasthan,India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2011年第3期8卷 264-268页

作者： Mohammed Abdul Rasheed Mutnuri lakshmi Deshoju Srinu Anurodh Mohan Dayal Microbiology Laboratory Petroleum Geochemistry DivisionNational Geophysical Research InstituteCouncil for Scientific and Industrial Research (CSIR)Uppal RoadHyderabad-500606India

Geo-microbial prospecting for hydrocarbons is an exploration method based on the seepage of light gaseous hydrocarbons from oil/gas reservoirs to the surface and their utilization by hydrocarbon oxidizing bacteria. These bacteria utilize hydrocarbon gases as their sole source of food and are found to be enriched in the near surface soils/sediments above the oil and gas reservoirs. The detection of anomalous populations of n-pentane and n-hexane oxidizing bacteria in the surface soils can help to evaluate the prospects for hydrocarbon exploration. A geo-microbial survey has been carried out in the Bikaner Nagaur basin to investigate the prospects for hydrocarbon exploration. In the present study, bacterial counts for n-pentane utilizing bacteria range between 2.0× 10^2 and 1.26× 10^6 cfu/gm and n-hexane utilizing bacteria range between 2.0× 10^2 and 1.21 × 10^6 cfu/gm. The bacterial concentration distribution maps show four distinct anomalies in the study area. The possibility of discovering oil or gas reservoirs using the microbiological method is emphasized by the tact that the hydrocarbon-oxidizing bacteria range between 103 and 106 cfu/gm in soil/sediment receiving hydrocarbon micro-seepages. In the present study area of the Bikaner Nagaur basin, n-pentane and n-hexane utilizing bacteria are found between 105 and 106 cfu/gm of soil sample, which is significant and thereby substantiates the seepage of lighter hydrocarbon accumulations from oil and gas reservoirs. Geo-microbial prospecting studies suggest that hydrocarbon micro-seepage of subsurface origin is present in the study area and indicate that the area has positive prospects for petroleum exploration.

关键词： Hydrocarbon utilizing bacteria microbial prospecting micro-seepage petroleum exploration

Evaluation of 1-Chloroacetophenone (CN) and Dibenz (b, f)-1, 4 oxazepine (CR) Induced Respiratory Tract Sensory Irritation Following a Simple Inhalation Exposure Method in Mice

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1998年第2期11卷 171-178页

作者： PRAVIN KUMAR AND A. S. SACHAN(Division of Pharmacology and Toxicology, Defence Research and Development Establishment, jhansi Road,Gwalior-474002, India)(To whom all correspondence should be addressed.) Division of Pharmacology and Toxicology Defence Research and Development Establishment Jhansi Road Gwalior-474002 India

Sensory irritation of the upper respiratory tract was induced in mice by inhalation of vapors, generated under thermal stress of two tear gases viz. 1-chloroacetophenone (CN) and dibenz (b, f)-1, 4 oxazepine (CR) following a simple exposure technique. A known quantity of the irritant was kept in an adapter fitted with glass exposure chamber, heated, and the vapor thus generated was purged into the chamber. The restrained mouse inhaled the vapor, and the resultant depression of respiratory rate was recorded on a polygraph. Fifty percent depression of the respiration rate and the corresponding air concentration of the irritant was determined by obtaining the linear curve fitting equation and putting the value of Y=50. It was concluded that inhalation of CR vapor was 2. 66 times more irritating than that of CN in mice. The employed exposure method also proved to be simple, sensitive, easy t0 operate,and may also prove useful in evaluating irritation of upper respiratory tract fOllowing the inhalation of vapors of various chemicals.

关键词： Evaluation of 1-Chloroacetophenone and Dibenz CN CR

A New Gastroprotective Effect of Limonoid Compounds Xyloccensins X and Y from Xylocarpus Molluccensis in Rats

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Natural Products and Bioprospecting 2014年第5期4卷 277-283页

作者： Vijai lakshmi Vaibhav Mishra Gautam Palit Division of Medicinal and Process Chemistry Central Drug Research InstituteLucknow 226001UPIndia Department of Biochemistry King George Medical UniversityLucknow 226003India Division of Pharmacology Central Drug Research InstituteLucknow 226001UPIndia

Gastric ulcer is a very common gastrointestinal disorder affecting a large number of people *** arises due to an imbalance between aggressive(acid,pepsin and Helicobacter pylori infection)and protective(mucin secretion,prostaglandin,epidermal growth factors and bicarbonate)factors in the *** this study,the gastroprotective activity has been investigated of the active constituents from Xylocarpus *** activity of xyloccensins X?Y was investigated and found to be active in various ulcer models in Sprague–Dawley(SD)*** understand the mechanism of action of active constituent of natural products,the effects of the compounds on antisecretory and cytoprotective activities were *** dried fruits were extracted with ethanol and fractionated into four *** X?Y were isolated from the active fraction and was tested against different ulcer *** X?Y were found to possess anti-ulcerogenic *** antiulcer activity might be due to its anti-secretory activity and subsequent strengthening of the defensive *** present study has helped us in identifying a new lead in the form of xyloccensins that could be exploited in the treatment of gastric ulcer disease.

关键词： Gastric ulcer Xyloccensins X?Y Antiulcerogenic activity

Pervasive underwater passive target tracking for the computation of standard deviation solution in a 3D environment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Intelligent Computing and Cybernetics 2021年第4期14卷 580-597页

作者： M.Kavitha lakshmi S.Koteswara Rao Kodukula Subrahmanyam Computer Science and Engineering Koneru Lakshmaiah Education FoundationGunturIndia Electronics and Communications Engineering Koneru Lakshmaiah Education FoundationGunturIndiaand

Purpose-Nowadays advancement in acoustic technology can be explored with marine *** purpose of the paper is pervasive computing underwater target tracking has aroused military and civilian interest as a key component of ocean *** many pervasive techniques are currently found in the literature,there is little published research on the effectiveness of these paradigms in the target tracking ***/methodology/approach-The unscented Kalman filter(UKF)provides good results for bearing and elevation angles only *** methodology and mathematical modeling are carried out and used to analyze the performance of the filter based on the Monte Carlo ***-Due to the intricacy of maritime surroundings,tracking underwater targets using acoustic signals,without knowing the range parameter is *** intention is to find out the solution in terms of standard deviation in a three-dimensional(3D)***/value-A new method is found for the acceptance criteria for range,course,speed and pitch based on the standard deviation for bearing and elevation 3D target tracking using the unscented Kalman filter covariance *** the Monte Carlo simulation,several scenarios are used and the results are shown.

关键词： Unscented Kalman filter Underwater target tracking Acceptance criteria Three-dimensional target tracking Standard deviation

Forensic Science and its Limitations in Rape and Murder Cases in India

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Forensic Science and Medicine 2023年第1期9卷 91-97页

作者： J lakshmi Charan K Sita Manikyam Dr.B.R.Ambedkar College of Law Andhra UniversityVisakhapatnamAndhra PradeshIndia

Forensic science plays a significant role in crime scene analysis and other evidence collection(such as clothes,cigarette butts,blood,semen,hair,etc.,)to scientifically establish the accused’s *** rape and murder cases,DNA tests confirm the victim’s *** provides certain evidence that is helpful in the speedy investigation and conclusion of a ***,it is not a foolproof science and it has certain ***,the first responders,such as the Crime Laboratory Ultimate Evidence System team and the forensic experts,must keep these limitations in mind during sample collection and examination,otherwise,it may lead to incorrect *** incorrect results may be obtained due to insufficient sample quantity,improper collection methods,or delay in an *** is highly recommended to implement standard operating procedure guidelines,failing which the admissibility of such forensic evidence to prove beyond all reasonable doubts is at ***,the court shall acquit the accused giving him the benefit of *** article focuses on the applicability and limitations of forensic science in the Indian Criminal Justice System and the need to adopt due protocols to yield viable results.

关键词： Crime scene forensic science Indian criminal justice system rape standard operating procedure

Noninvasive in vivo cell tracking using molecular imaging:A useful tool for developing mesenchymal stem cell-based cancer treatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2020年第12期12卷 1492-1510页

作者： Ramya lakshmi Rajendran Manasi Pandurang Jogalekar Prakash Gangadaran Byeong-Cheol Ahn Department of Nuclear Medicine Kyungpook National UniversityDaegu 41944South Korea Brigham and Women’s Hospital Harvard Medical SchoolBostonMA 02115United States Department of Nuclear Medicine School of MedicineKyungpook National UniversityDaegu 41944South Korea BK21 Plus KNU Biomedical Convergence Program Department of Biomedical ScienceSchool of MedicineKyungpook National UniversityDaegu 41944South Korea Department of Nuclear Medicine School of MedicineKyungpook National UniversityKyungpook National University HospitalDaegu 41944South Korea

Mounting evidence has emphasized the potential of cell therapies in treating various diseases by restoring damaged tissues or replacing defective cells in the *** therapies have become a strong therapeutic modality by applying noninvasive in vivo molecular imaging for examining complex cellular processes,understanding pathophysiological mechanisms of diseases,and evaluating the kinetics/dynamics of cell *** particular,mesenchymal stem cells(MSCs)have shown promise in recent years as drug carriers for cancer *** can also be labeled with different probes and tracked in vivo to assess the in vivo effect of administered cells,and to optimize *** exact role of MSCs in oncologic diseases is not clear as MSCs have been shown to be involved in tumor progression and inhibition,and the exact interactions between MSCs and specific cancer microenvironments are not *** this review,a multitude of labeling approaches,imaging modalities,and the merits/demerits of each strategy are *** addition,specific examples of the use of MSCs and in vivo imaging in cancer therapy are ***,present limitations and future outlooks in terms of the translation of different imaging approaches in clinics are discussed.

关键词： Cell therapy Mesenchymal stem cells In vivo molecular imaging Drug delivery Superparamagnetic iron oxide