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Abundance and Ecology of Endemic Asterorotalia trispinosa from the Western Bay of Bengal: Implications for its Application as a Paleomonsoon Proxy

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Acta Geologica Sinica(English Edition) 2017年第6期91卷 2268-2282页

作者： Rajeev SARASWAT Manumalenki MANASA Thejasino SUOKHRIE Mohammad Syed SAALIM Rajiv NIGAM Micropaleontology Laboratory CSIR-National Institute of Oceanography

A total of 97 surface sediment samples were collected from the continental shelf and slope of the western Bay of Bengal to assess the potential application of Asterorotalia trispinosa as a paleomonsoon proxy. The relative abundance of living as well as total （living and dead） A. trispinosa ranges from being absent to a maximum of-31%. The highest abundance ofA. trispinosa is close to the outfall region of the Ganga-Brahmaputra Rivers and decreases away from the river mouths. Contrary to that, A. trispinosa is rare in front of both the Cauvery and Pennar river outfall regions, in the central part of the western Bay of Bengal. The living A. trispinosa abundance is the lowest in between two major river systems, viz. Ganga-Brahmaputra-Mahanadi and Krishna-Godavari. The relative abundance of both the total and living A. trispinosa is strongly positively correlated with ambient seawater temperature, and negatively correlated with %Corg and salinity. Based on the spatial distribution, we conclude that A. trispinosa is stenohaline in nature, rather than euryhaline, and further that the increased relative abundance of A. trispinosa indicates warmer and only marginally hyposaline environment. Even though the ecological preference of A. trispinosa suggests it as a potential paleomonsoon proxy, the restricted distribution implies limited application.

关键词： Asterorotalia trispinosa ecology paleomonsoon riverine influx Bay of Bengal

How will Benthic Foraminifera Respond to Warming and Changes in Productivity ?: A Laboratory Culture Study on Cymbaloporetta plana

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Acta Geologica Sinica(English Edition) 2019年第1期93卷 175-182页

作者： KURTARKAR R.Sujata saraswat rajeev KAITHWAR Amrata NIGAM Rajiv Micropaleontology Laboratory Geological Oceanography Division National Institute of Oceanography

Anthropogenic activities are likely to cause global warming. Global warming will affect marine productivityand thus food availability for marine organisms. Both the seawater temperature and food availability affect benthicforaminifera, the most abundant marine calcareous microorganisms. Therefore, a laboratory culture experiment wasconducted on Cymbaloporetta plana to understand the coupled effect of temperature(25°C, 27°C, 30°C) and food(102±5,203±9, 305±14, 407±18, 508±23 diatom cells). At all temperatures, growth increased with increase in food. The specimenssubjected to 27°C temperature attained the maximum growth and those subjected to 25°C were the smallest. All specimensfed with 508±23 cells reproduced, 0 irrespective of temperature. Of all the specimens without food, 40% at 27°C and 20% at25°C reproduced, whereas specimens subjected to 30°C did not reproduce. The 100% rate of reproduction at 27°C suggeststhat it is the optimum temperature for growth and reproduction. All the specimens at 30°C and without additional food,died, whereas at 25°C and 27°C, the mortality rate was 80% and 60%, respectively. The limited growth and reproductionwith decreasing food clearly indicates that food availability also controls the growth and reproduction of shallow waterbenthic foraminifer C. plana. Therefore, warming coupled with decreasing productivity is likely to severely affect thegrowth and abundance of shallow water benthic foraminifera.

关键词： Cymbaloporetta plana culture experiment temperature food reproduction

Linkage between Seasonal Insolation Gradient in the Tropical Northern Hemisphere and the Sea Surface Salinity of the Equatorial Indian Ocean during the Last Glacial Period

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Acta Geologica Sinica(English Edition) 2012年第5期86卷 1265-1275页

作者： saraswat rajeev Nigam RAJIV Mackensen ANDREAS Weldeab SYEE Micropaleontology Laboratory National Institute of OceanographyGoaIndia Alfred Wegner Institute for Polar and Marine Research BremerhavenGermany Department of Earth Science University of CaliforniaSanta BarbaraUSA

Paired stable oxygen isotope and Mg/Ca analyses in calcite tests of the mixed-layer-dwelling planktic foraminifer Globigerinoides ruber has been used to reconstruct equatorial Indian Oceanδ18O of seawater （δ 18Osw ） over the last ~137 thousand years. On the basis of ice-volume-correctedδ18Osw （δ18Osw-ivc ）, relative changes in sea surface salinity （SSS） have been estimated. The SSS estimates suggest three episodes of higher SSS （131-113 thousand years before present （kyr BP）, 62-58 kyr BP, and 30-24 kyr BP） within the last glacial period as compared with the present. SSS comparison between interglacial episodes reveals that the surface seawater over the core site was significantly saltier during the penultimate interglacial than the Holocene. We suggest that the evolution of a seasonal insolation gradient between the Indian monsoon areas and the equator over the investigated time interval was instrumental in shaping the strength of the Indian winter and summer monsoons that left their imprints on the equatorial Indian Ocean SSS via freshwater input and wind-induced mixing. The study shows that the insolation difference between northern latitudes and the equator during winter affects monsoon strength in the Indian region, especially during cold intervals.

关键词： oxygen isotope Mg/Ca Globigerinoides ruber salinity insolation Indian Ocean

Multiphysics of multifunctional nanofluids based on different oxides nanoparticles and glycerol fluid

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Particuology 2023年第5期76卷 46-62页

作者： R.J.Sengwa Mukul saraswat Dielectric Research Laboratory Department of PhysicsJai Narain Vyas UniversityJodhpur342005India

Nanofluid(NF)materials consisting of glycerol(Gly)and different inorganic nano oxides(TiO_(2),ZnO,Al_(2)O_(3),and SiO_(2) for the oxides concentration of 0.01 wt%to the weight of Gly base fluid)were prepared by a two-step method through ultrasonic cavitation process.These nanofluids were investigated by employing an X-ray diffractometer(XRD),ultraviolet-visible(UV-Vis)spectrophotometer,20 Hz to 1 MHz frequency range dielectric relaxation spectroscopy(DRS),ultrasonic interferometer,and rotational viscometer.The multiphysics of these nanofluids includes structural and optical properties,dielectric permittivity,electrical conductivity,conductivity relaxation,ultrasound velocity,adiabatic compress-ibility,acoustic impedance,viscosity,density,thermal conductivity,and viscoacoustic relaxation were characterized.The XRD patterns identified monodispersed and stable suspensions of these different characteristic nanoparticles in the hydrogen-bonded 3D supramolecular structure of ultra-high viscous glycerol fluid which were supported by their UV-Vis absorbance analyses.The energy band gap values of the TiO_(2)and ZnO containing nanofluids were found primarily ruled by the characteristic optical prop-erties of these oxides nanomaterials.The complex dielectric and various electrical functions studied at 25℃revealed that the suspension of different oxide nanoparticles in the glycerol fluid increased the static permittivity whereas reduced the direct current electrical conductivity which showed strong conductivity relaxation process dependence.The rheological measurements of the formulated nanofluids were performed over a shear rate range of 0.4-40 s^(-1)at temperatures of 25-55℃.The linear rela-tionship between shear rate and shear stress and also the shear rate-independent viscosity revealed the Newtonian behaviour of these nanofluids.The shear viscosity non-linearly decreased with the increase of temperature and exhibited the Arrhenius behaviour for all different oxides containing Gly-based nanofluids.The acoustic parameters

关键词： Glycerol Nano oxides Nanofluids Optical properties Dielectric properties Thermophysical parameters

FedRec:Trusted rank-based recommender scheme for service provisioning in federated cloud environment

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Digital Communications and Networks 2023年第1期9卷 33-46页

作者： Ashwin Verma Pronaya Bhattacharya Umesh Bodkhe Deepti saraswat Sudeep Tanwar Kapal Dev Department of Computer Science and Engineering Institute of TechnologyNirma UniversityAhmedabadGujarat382481India Department of Institute of Intelligent Systems University of JohannesburgPO Box 524South Africa

The emergence of on-demand service provisioning by Federated Cloud Providers(FCPs)to Cloud Users(CU)has fuelled significant innovations in cloud provisioning models.Owing to the massive traffic,massive CU resource requests are sent to FCPs,and appropriate service recommendations are sent by FCPs.Currently,the FourthGeneration(4G)-Long Term Evolution(LTE)network faces bottlenecks that affect end-user throughput and latency.Moreover,the data is exchanged among heterogeneous stakeholders,and thus trust is a prime concern.To address these limitations,the paper proposes a Blockchain(BC)-leveraged rank-based recommender scheme,FedRec,to expedite secure and trusted Cloud Service Provisioning(CSP)to the CU through the FCP at the backdrop of base 5G communication service.The scheme operates in three phases.In the first phase,a BCintegrated request-response broker model is formulated between the CU,Cloud Brokers(BR),and the FCP,where a CU service request is forwarded through the BR to different FCPs.For service requests,Anything-as-aService(XaaS)is supported by 5G-enhanced Mobile Broadband(eMBB)service.In the next phase,a weighted matching recommender model is proposed at the FCP sites based on a novel Ranking-Based Recommender(RBR)model based on the CU requests.In the final phase,based on the matching recommendations between the CU and the FCP,Smart Contracts(SC)are executed,and resource provisioning data is stored in the Interplanetary File Systems(IPFS)that expedite the block validations.The proposed scheme FedRec is compared in terms of SC evaluation and formal verification.In simulation,FedRec achieves a reduction of 27.55%in chain storage and a transaction throughput of 43.5074 Mbps at 150 blocks.For the IPFS,we have achieved a bandwidth improvement of 17.91%.In the RBR models,the maximum obtained hit ratio is 0.9314 at 200 million CU requests,showing an improvement of 1.2%in average servicing latency over non-RBR models and a maximization trade-off of QoE index of 2.7688 at the flow request 1.088 and at granted serv

关键词： Blockchain 5G-enhanced mobile broadband Federated clouds Rank-based recommender model Smart contracts

Rigid body dynamics modeling, experimental characterization, and performance analysis of a howitzer

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Defence Technology（防务技术） 2016年第6期12卷 480-489页

作者： Nachiketa TIWARI Mukund PATIL Ravi SHANKAR Abhishek saraswat Rituraj DWIVEDI Department of Mechanical Engineering Indian Institute of Technology Ordnance Factory Kanpur India

A large caliber howitzer is a complex and cumbersome assembly. Understanding its dynamics and performance attributes' sensitivity to changes in its design parameters can be a very time-consuming and expensive exercise, as such an effort requires highly sophisticated test rigs and platforms. However, the need of such an understanding is crucially important for system designers, users, and evaluators. Some of the key performance attributes of such a system are its vertical jump, forward motion, recoil displacement, and force transmitted to ground through tires and trail after the gun has been fired. In this work, we have developed a rigid body dynamics model for a representative howitzer system, and used relatively simple experimental procedures to estimate its principal design parameters. Such procedures can help in obviating the need of expensive experimental rigs, especially in early stages of the design cycle. These parameters were subsequently incorporated into our simulation model,which was then used to predict gun performance. Finally, we conducted several sensitivity studies to understand the influence of changes in various design parameters on system performance. Their results provide useful insights in our understanding of the functioning of the overall system.

关键词： Howitzer gun CAD modeling Dynamic simulation Recoil assembly parameters Sensitivity analysis

Charged current quasi-elastic scattering of vμoff^12C

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Chinese Physics C 2018年第12期42卷 25-31页

作者： Deepika Grover Kapil saraswat Prashant Shukla Venktesh Singh Department of Physics Institute of ScienceBanaras Hindu UniversityVaranasi 221005India Nuclear Physics Division Bhabha Atomic Research CentreMumbai 400085India Homi Bhabha National Institute Anushakti NagarMumbai 400094India

In this work, we study charged current quasi-elastic scattering （QES） of vμ off nucleon and nucleus using a formalism based on the Llewellyn Smith （LS） model. Parameterizations by Galster et al. are used for electric and magnetic Sach＇s form factors of the nucleons. We use the Fermi gas model along with the Pauli suppression condition to take into account the nuclear effects in the anti-neutrino-nucleus QES. We calculate vμ-p and vμ-^12C charged current quasi-elastic scattering differential and total cross sections for different values of axial mass MA, and compare the results with data from the GGM, SKAT, BNL, NOMAD, MINERVA and MiniBooNE experiments. The present theoretical approach gives a good description of differential cross section data. The calculations with axial mass MA =0.979 and 1.05 GeV are compatible with data from most of the experiments.

关键词： cross section quasi-elastic scattering axial mass form factors

Day Time Seasonal Variation of Ozone and Its Association with Methane at Different Pressures over Barrow, Alaska

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Atmospheric and Climate Sciences 2022年第2期12卷 462-474页

作者： Nikunj Jaitawat Vimal saraswat Department of Physics Bhupal Nobles’ University Udaipur India

This study has explored the seasonal day time variations of the two most important trace gases involved in global warming i.e., Methane (CH4) and Ozone (O3). Since solar activities also play a vital role in the formation of ozone, and hence solar flux data is also consulted in the present paper. Here we have discussed, day hours seasonal variation of O3, solar flux and CH4 at different pressures for four different seasons i.e., winter, summer, autumn and spring. We have evaluated the correlation between O3, solar flux and CH4 over an American station “Barrow, Alaska” for a period of 18 years and conclude that in every season of the year, CH4 shows linear increment with a good significance level above 95%. The autumn season shows a good correlation between solar flux and O3 with a maximum value of 0.53 in October and a minimum value of 0.34 in November month. In the winter season, CH4 shows linear increment with a significance level above 95% at every pressure height. We also conclude that O3 shows an increment trend in March and April months, but its negative trend is found in May month of the spring season.

关键词： Surface Ozone Methane Solar Flux Climate and Season

Uterine prolapse in buffaloes: A review

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Asian pacific Journal of Reproduction 2018年第6期7卷 241-247页

作者： GN Purohit Atul Shanker Arora Tilok Gocher Mitesh Gaur Chandra Shekher saraswat Pankaj Mishra Department of Veterinary Gynecology and Obstetrics College of Veterinary and Animal SciencesRajasthan University of Veterinary and Animal Sciences BikanerRajasthanIndia Directorate of Extension Education Rajasthan University of Veterinary and Animal SciencesBikanerRajasthanIndia Department of Veterinary Gynecology and Obstetrics College of Veterinary and Animal ScienceNavaniaVallabhnagarUdaipurIndia Department of Veterinary Extension Education College of Veterinary and Animal ScienceRajasthan University of Veterinary and Animal SciencesBikanerRajasthanIndia

Uterine prolapse is an emergency postpartum problem occurring within 24 h of parturition and resulting in death or serious complications in unattended cases. Poor myometrial contractions during the post-partum period and traction during difficult births are two postulated etiologies and low serum calcium appear to be a significant risk factor for uterine prolapse in buffaloes. Shortly after eversion the uterus gets inflamed and edematous and shock may ensue in cases with excessive bleeding. Prompt replacement of prolapsed uterus with sufficient care assures good prognosis. The etiology, risk factors, clinical findings and approaches for therapy of uterine prolapse in buffaloes are mentioned in this review.

关键词： Uterine prolapse Prognosis Risk factors Therapy