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Salton Sea: An ecosystem in crisis

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International Journal of Biomathematics 2018年第8期11卷 363-392页

作者： ranjit kumar upadhyay Sarita kumari Sangeeta kumari Department of Applied Mathematics Indian Institute of Technology (ISM) Dhanbad 826004 Jharkhand India

Salton Sea (a destination resort) is to be saved from being converted into a skeletonfilled wasteland. The critical amount of water flowing into the sea to maintain its level and salinity has been diverted since January 2018. This will lead to shrinking volumes and increasing salinities. Ecological consequences and public health impacts of altered conditions will be phenomenal. We design and analyze a minimal eco-epidemiological model to figure out future journey of this sea;a way station for fish-eating migratory birds. The mathematical model has been assembled in terms of prey-predator interaction. The salient feature of the proposed model is its seasonally varying contact rate which represents rate of conversion of susceptible fishes into infectives. We have analytically investigated the global stability, disease persistence and periodic solutions of the proposed model system. Susceptible prey-induced periodic solution is globally asymptotically stable when R01 *** stability and Hopf bifurcation (HB) analysis help us extract parameter values to explore the dynamical behavior of the model system. Two-dimensional parameter scans and bifurcation diagrams reveal that the model displays propensity towards chaotic dynamics, which is associated with extinction-sized population densities. In the presence of stochastic external forces, this implies extinction of most of the fish species. This, in turn, suggests that resident birds will have to migrate to other destinations. The fish-eating migratory birds will be forced to switch over to invertebrates. Ecological consequences and public health impacts of this transition would be severe. Conservation groups are solicited to draw attention of the government to avert this impounding danger. It is important to plan for an ecosystem-wide transition such that impacts on birds and on human inhabitants living adjacent to the shrinking and salinizing sea are minimized

关键词： Eco-epidemiological model seasonally varying contact rate diseases in fish species avian predator chaotic dynamics fish-eating migratory birds invertebrates

Harmful algal blooms in fresh and marine water systems： The role of toxin producing phytoplankton

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International Journal of Biomathematics 2016年第3期9卷 191-210页

作者： Nilesh kumar Thakur S. K. Tiwari ranjit kumar upadhyay Department of MathematicsNational Institute of Technology Raipur 492010 Department of Applied MathematicsIndian School of Mines Dhanbad 826004

In this paper, we have investigated a model with three interacting species： non-toxic phy- toplankton, toxic phytoplankton and zooplankton with Holling type II and III functional responses over the space and time. The role of toxin producing phytoplankton （TPP） has been studied. We have presented the theoretical analysis of pattern formation in spatially distributed population with local diffusion. The paper highlights the hetero- geneity of HABs over space and time. The choice of parameter values and the functional response is important to study the effect of TPP, also it would depend more on the non- linearity of the system. With the help of numerical simulations, we have observed the spatial and spatiotemporal patterns for plankton system. This study demonstrates that TPP plays an important role in controlling the dynamics. We have observed that prey＇s anti-predator efforts promote predator switching. It has been found that high predation of TPP helps for the coexistence of toxic, non-toxic phytoplankton and zooplankton population.

关键词： Plankton harmful algal bloom toxin producing phytoplankton spatiotem-poral pattern.

Exploring the dynamics of a Holling-Tanner model with cannibalism in both predator and prey population

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International Journal of Biomathematics 2018年第1期11卷 225-253页

作者： Aladeen Al Basheer Rana D. Parshad Emmanuel Quansah Shengbin Yu ranjit kumar upadhyay Mathematics Department The University of Georgia 240A Riverbend Rd Athens GA 30602 USA Department of Mathematics Clarkson University Potsdam New York 13699 USA Pacific Source Health PlansSpringfield Oregon 97477 USA Department of Basic Teaching and ResearchYango University Fuzhou Fujian 350015 P. R. China Department of Applied MathematicsIndian Institute of Technology (ISM) Dhanbad 826004 Jharkhand India

Cannibalism is an intriguing life history trait, that has been considered primarily in the predator, in predator-prey population models. Recent experimental evidence shows that prey cannibalism can have a significant impact on predator-prey population dyna- mics in natural communities. Motivated by these experimental results, we investigate a ratio-dependent Holling-Tanner model, where cannibalism occurs simultaneously in both the predator and prey species. We show that depending on parameters, whilst prey or predator cannibalism acting alone leads to instability, their joint effect can actually stabilize the unstable interior equilibrium. Furthermore, in the spatially explicit model, we find that depending on parameters, prey and predator cannibalism acting jointly can cause spatial patterns to form, while not so acting individually. We discuss ecologicalconsequences of these findings in light of food chain dynamics, invasive species control and climate change.

关键词： Holling-Tanner model prey cannibalism predator cannibalism stability global attraction Turing instability.

Electro-magnetohydrodynamic Flow of Biofluid Induced by Peristaltic Wave： A Non-newtonian Model

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Journal of Bionic Engineering 2016年第3期13卷 436-448页

作者： Gopal Chandra Shit Nayan kumar ranjit Aniruddha Sinha Department of Mathematics Jadavpur University Kolkata - 700032 India Yogoda Satsanga Palpara Mahavidyalaya Purba Medinipur - 721458 India

This article aims to develop a mathematical model for peristaltic transport of magnetohydrodynamic flow of biofluids through a micro-channel with rhythmically contracting and expanding walls under the influence of an applied electric field. The couple stress fluid model is considered to represent the non-Newtonian characteristics ofbiofluids. The velocity slip condition at the channel walls is taken into account because of the hyclrophilic/hydrophobic interaction with negatively charged walls. The essential features of the electromagnetohydrodynamic flow of biofluid through micro-channels are clearly highlighted in the variations of the non-dimensional parameters of the physical quantities of interest such as the velocity, wall shear stress, pressure gradient, pressure rise per wave length, frictional force at the channel walls and the distribution of stream function. It reveals that the flow ofhiofluid is appreciably influenced by the sufficient strength of externally applied magnetic field and electro-osmotic parameter. The velocity slip condition reduces the frictional force at the channel wall. Moreover, the formation of the trapping bolus strongly depends on electro-osmotic parameter and magnetic field strength.

关键词： peristaltic transport couple stress fluid magnetohydrodynamics electro-osmosis

Impact of geomorphometric parameters on the occurrence and distribution of landslides in Yamuna River Basin,North-Western Himalaya,India

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Journal of Mountain Science 2022年第8期19卷 2374-2396页

作者： Ravi SHANKAR Gyan Prakash SATYAM Prakash kumar SINGH Nilesh kumar RAI ranjit kumar PASWAN REED CSIR-Central Institute of Mining and Fuel ResearchDhanbad 826001India Department of Applied Geology Indian Institute of Technology(ISM)Dhanbad 826004India Department of Earth and Planetary Sciences University of AllahabadPrayagraj 211002Uttar PradeshIndia

The majority of landslides in the Indian Himalayas are triggered by rainfall and *** geology and geomorphology also play an important role and constitute the major predisposing factor controlling ***,active tectonics modify the landscape,impacting the occurrence and distribution of *** objective of this study is to investigate the role of some of the major predisposing factors to assess landslide patterns in the Yamuna River Basin as it is prone to recurrent landslide *** approach mainly deals with the application of geographical information system-based statistical analysis and quantifying frequency-area distribution of rainfalltriggered landslides for the years 2015 to *** analysis shows that the frequency of landslides is highest in the slope range 40°-70°and the mean landslide size is higher in the slope range 0°-20°and 30°-40°,remaining constant on further increase in slope *** study shows that some critical slope range controls both the frequency and size of *** were mostly restricted to south facing *** 91%of the landslide occur in the drainage density range of 1.2 to 2.1 km/km^(2) while landslides show very low occurrence in either lower(2.1)drainage *** distribution analysis of landslides depicts a distinct cutoff point but an indistinct rollover ***-sampling of small landslides can be a reasonable cause for *** other studies,the present data fits very well for medium and large landslides following an inverse power law with a scaling exponent *** 80% of landslides are smaller than the cutoff size and 20% larger than this *** geology and tectonics of Lesser Himalayas and Sivaliks offer favorable conditions for frequent *** such as Dehradun,Uttarkashi,Sirmaur,Shimla,and Solan are very prone to landslide activity owing to the presence of poorly consolidated sandstone,conglomerate,quartzites,phylli

关键词： Himalaya Geomorphometry Landslide Yamuna River Basin

Tracing overlapping biological signals in mid-infrared using colonic tissues as a model system

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World Journal of Gastroenterology 2017年第2期23卷 286-296页

作者： ranjit kumar Sahu Ahmad Salman Shaul Mordechai Department of Physics Ben Gurion University Department of Medicine University of Virginia Department of Physics SCE-Shamoon College of Engineering

AIMTo understand the interference of carbohydrates absorbance in nucleic acids signals during diagnosis of malignancy using Fourier transform infrared (FTIR) *** used formalin fixed paraffin embedded colonic tissues to obtain infrared (IR) spectra in the mid IR region using a bruker II IR microscope with a facility for varying the measurement area by varying the aperture available. Following this procedure we could measure different regions of the crypt circles containing different biochemicals. Crypts from 18 patients were measured. Circular crypts with a maximum diameter of 120 μm and a lumen of about 30 μm were selected for uniformity. The spectral data was analyzed using conventional and advanced computational *** the various components that are observed to contribute to the diagnostic capabilities of FTIR, the carbohydrates and nucleic acids are prominent. However there are intrinsic difficulties in the diagnostic capabilities due to the overlap of major absorbance bands of nucleic acids, carbohydrates and phospholipids in the mid-IR region. The result demonstrates colonic tissues as a biological system suitable for studying interference of carbohydrates and nucleic acids under ex vivo conditions. Among the diagnostic parameters that are affected by the absorbance from nucleic acids is the RNA/DNA ratio, dependent on absorbance at 1121 cm-1 and 1020 cm-1 that is used to classify the normal and cancerous tissues especially during FTIR based diagnosis of colonic malignancies. The signals of the nucleic acids and the ratio (RNA/DNA) are likely increased due to disappearance of interfering components like carbohydrates and phosphates along with an increase in amount of *** present work, proposes one mechanism for the observed changes in the nucleic acid absorbance in mid-IR during disease progression (carcinogenesis).

关键词： Spectral interference Fourier transform infrared diagnosis Nucleic acids Malignancy Colonic tissue

Aspects of high-performance and bio-acceptable magnetic nanoparticles for biomedical application

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Asian Journal of Pharmaceutical Sciences 2021年第6期16卷 704-737页

作者： Preeti Kush Parveen kumar ranjit Singh Ajeet Kaushik School of Pharmacy Adarsh Vijendra Institute of Pharmaceutical SciencesShobhit University GangohSaharanpurUttar Pradesh 247341India Nanotechnology Division(H-1) CSIR-Central Scientific Instruments OrganizationChandigarh 160030India NanoBioTech Laboratory Health System EngineeringDepartment of Natural SciencesFlorida Polytechnic UniversityLakelandFL 33805-8531United States

This review covers extensively the synthesis&surface modification,characterization,and application of magnetic *** biomedical applications,consideration should be given to factors such as design strategies,the synthesis process,coating,and surface *** synthesis method regulates post-synthetic change and specific applications in vitro and in vivo imaging/diagnosis and pharmacotherapy/*** insights have been provided on biodistribution,pharmacokinetics,and toxicity in a living system,which is imperative for their wider application in *** nanoparticles can be decorated with multiple contrast agents and thus can also be used as a probe for multi-mode imaging or double/triple imaging,for example,MRI-CT,*** loading with different drug molecules/dye/fluorescent molecules and integration with other carriers have found application not only in locating these particles in vivo but simultaneously target drug delivery/hyperthermia inside the *** are underway to collect the potential of these magnetically driven nanoparticles in various scientific fields such as particle interaction,heat conduction,imaging,and ***,this comprehensive data will help in the further development of advanced techniques for theranostics based on high-performance magnetic nanoparticles and will lead this research area in a new sustainable direction.

关键词： Magnetism Synthesis Characterization Delivery Imaging Biodistribution Pharmacokinetic

Deep Convolutional Network Based Machine Intelligence Model for Satellite Cloud Image Classification

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Big Data Mining and Analytics 2023年第1期6卷 32-43页

作者： Kalyan kumar Jena Sourav kumar Bhoi Soumya Ranjan Nayak ranjit Panigrahi Akash kumar Bhoi Department of Computer Science and Engineering Parala Maharaja Engineering CollegeBerhampur 761003India Amity School of Engineering and Technology Amity UniversityUttar Pradesh 201303India Department of Computer Applications Sikkim Manipal Institute of TechnologySikkim Manipal UniversitySikkim 737102India Directorate of Research Sikkim Manipal UniversityGangtokSikkim 737102India

As a huge number of satellites revolve around the earth,a great probability exists to observe and determine the change phenomena on the earth through the analysis of satellite images on a real-time ***,classifying satellite images plays strong assistance in remote sensing communities for predicting tropical *** this article,a classification approach is proposed using Deep Convolutional Neural Network(DCNN),comprising numerous layers,which extract the features through a downsampling process for classifying satellite cloud *** is trained marvelously on cloud images with an impressive amount of prediction *** time decreases for testing images,whereas prediction accuracy increases using an appropriate deep convolutional network with a huge number of training dataset *** satellite images are taken from the Meteorological&Oceanographic Satellite Data Archival Centre,the organization is responsible for availing satellite cloud images of India and its *** proposed cloud image classification shows 94% prediction accuracy with the DCNN framework.

关键词： satellite images satellite image classification cyclone prediction Deep Convolutional Neural Network(DCNN) features layers down-sampling process

Characterization of Black Carbon in the Ambient Air of Agra,India:Seasonal Variation and Meteorological Influence

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Advances in Atmospheric Sciences 2017年第9期34卷 1082-1094页

作者： Pratima GUPTA Shalendra Pratap SINGH Ashok JANGID ranjit kumar Department of Chemistry Faculty of ScienceDayalbagh Educational Institute (Deemed University) Department of Physics and Computer Science Faculty of ScienceDayalbagh Educational Institute (Deemed University)

This study characterizes the black carbon in Agra, India home to the Taj Mahal--and situated in the lndo-Gangetic basin. The mean black carbon concentration is 9.5 μg m-3 and, owing to excessive biomass/fossil fuel combustion and automobile emissions, the concentration varies considerably. Seasonally, the black carbon mass concentration is highest in winter, probably due to the increased fossil fuel consumption for heating and cooking, apart from a low boundary layer. The nocturnal peak rises prominently in winter, when the use of domestic heating is excessive. Meanwhile, the concentration is lowest during the monsoon season because of the turbulent atmospheric conditions and the process of washout by precipitation. The ratio of black carbon to brown carbon is less than unity during the entire study period, except in winter （December）. This may be because that biomass combustion and diesel exhaust are major black carbon contributors in this region, while a higher ratio in winter may be due to the increased consumption of fossil fuel and wood for heating purposes. ANOVA reveals significant monthly variation in the concentration of black carbon; plus, it is negatively correlated with wind speed and temperature. A high black carbon mass concentration is observed at moderate （1-2 m s-1） wind speed, as compared to calm or turbulent atmospheric conditions.

关键词： black carbon aerosol seasonal variation diurnal variation meteorological parameter,