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Trace fossils of an amalgamated storm-bed succession from the Jurassic of the kachchh Basin,India:The significance of time-averaging in ichnology

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Journal of Palaeogeography 2018年第1期7卷 14-31页

作者： Franz To Fürsich Alfred Uchman Matthias Alberti Dhirendra k.pandey GeoZentrum Nordbayern Fachgruppe PalaoUmweltFriedrich-Alexander-Universitat Erlangen-Numberg Loewenichstra■e 2891054 ErlangenGermany Institute of Geological Sciences Jagiellonian UniversityGronostajowa 3a30-387KrakowPoland Institut fur Geowissenschaften Christian-Albrechts-Universitat zu KielLudewig-Meyn-Stral3e 1024118Kiel Germany Earth and Planetary Sciences GrouplPalaeontology Manipal Center for Natural SciencesManipal University Manipal 576104KarnatakaIndia

The uppermost part of the Upper Bathonian Sponge Limestone member, Patcham Formation, of the Jhura Dome of kachchh Mainland is a thickening-and shallowing-upward succession topped by medium-to thick-bedded hummocky cross-stratified grainstones deposited by storm waves. Occasionally, thin, commonly lenticular, intraclastic-bioclastic silty marl intercalations between the grainstones are highly bioturbated, in contrast to the grainstones, in which, for the most part, trace fossils occur scattered. Large exposures of bedding planes of the grainstones allow the detailed investigation of ichnological features, whereas the high density of traces in the soft marls precludes the identification of any ichnotaxa. Eighteen ichnotaxa have been recorded including Ophiomorpha, Thalassinoides, Taenidium, Gyrophyllites, Chondrites, Dactyloidites, Teichichnus, Bolonia, and Ancorichnus. Except for Ophiomorpha nodosa and Thalassinoides, which generally indicate moderate to high energy conditions and are the dwelling burrows of suspension-feeding to omnivorous crustaceans, the ichnotaxa represent a deposit-feeding behaviour of their producers and thus are characteristic of low-energy environments. The trace fossils form three ichnoassemblages characterized by(1) Ophiomorpha nodosa and Thalassinoides suevicus,(2)?Thalassinoides isp. A, Taenidium, and Bolonia lata,and(3) Ancorichnus. The dominance of traces of deposit-feeders in rocks indicative of high-energy events is counterintuitive and points to their non-contemporaneity. The sediments were deposited during brief highenergy events, whereas the trace fossils were produced when, after waning of storms low-energy conditions prevailed. This time-averaging is particularly pronounced in trace fossils that extend vertically downwards and may reach strata deposited under distinctly different conditions. Thus, environmental interpretations based on trace fossils should refer to colonisation surfaces rather than to the sediment surrounding th

关键词： Trace fossils Middle Jurassic kachchh Basin Taxonomy Time averaging Ichnology

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Slumping in the Upper Jurassic Baisakhi Formation of the Jaisalmer Basin, western India: Sign of synsedimentary tectonics?

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Journal of Palaeogeography 2017年第4期6卷 321-332页

作者： Matthias Alberti Dhirendra k.pandey Jitendra k.Sharma Narendra k.Swami Alfred Uchman Institut für Geowissenschaften Christian-Albrechts-Universitt zu Kiel Department of Geology University of Rajasthan Earth & Planetary Sciences Group/Palaeontology Manipal Center for Natural Sciences Manipal University Institute of Geological Sciences Jagiellonian University

A spectacularly exposed slump is described from a 120-m-long road cut between the villages of kanod and Deva in the northeastern Jaisalmer Basin of rajasthan,*** Upper Jurassic part of the sediments at the outcrop was formed in a near-shore setting and belongs to the Ludharwa Member of the Baisakhi *** 3-m-thick unit shows a number of asymmetric folds and thrust faults leading to an imbrication of partly lithified sandstone *** deformation structures allow the reconstruction of a movement towards the *** agrees well with the basin configuration that shows a deepening into this *** the determination of a specific trigger mechanism is difficult for soft-sediment deformation structures,an earthquake caused by synsedimentary tectonics in the basin seems to be the most likely explanation.

关键词： Sedimentology Mass movements Slumping Soft-sediment deformation structures Jaisalmer Basin Jurassic

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Diagnostic performance of C-reactive protein level and its role as a potential biomarker of severe dengue in adults

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Asian Pacific Journal of Tropical Medicine 2020年第8期13卷 358-365页

作者： raghavendra rao Snehal Nayak Akhilesh k pandey Shobha U kamath Department of Medicine Kasturba Medical CollegeManipalIndia Manipal Academy of Higher Education ManipalIndia Department of Biochemistry Kasturba Medical CollegeManipalIndia Department of Community Medicine Kasturba Medical CollegeManipalIndia

Objective: To determine the relationship between C-reactive protein(CrP) level and the severity of dengue and the potential use of CrP in predicting acute dengue ***: A prospective observational study was performed on dengue patients admitted to a tertiary care hospital in southern India. All patients of age above 18 years, diagnosed with dengue were included in the study. The detailed laboratory parameters pertaining to dengue were recorded. CrP levels were estimated and compared between groups i.e. severe and non-severe dengue. CrP cut-off value was detected using the receiver-operator ***: Totally 98 patients with a mean age of 40 years were included. Among them, 11.2% of the patients suffered from severe dengue, 54.1% of the cases had non-severe dengue without warning signs, and 34.7% had non-severe dengue with warning signs. The median CrP was significantly higher in patients with severe dengue compared to patients with non-severe dengue(96.2 mg/d L vs. 5.3 mg/d L). Univariate logistic regression analysis showed that the odd’s ratio(Or) of CrP was 1.053(P≤0.001, 95% CI=1.029-1.078). CrP at a cutoff value of 21.6 mg/L(0.929 AUC) had excellent sensitivity(100%) and specificity(81.6%) in predicting severe dengue infection. Multivariate logistic regression analysis showed that CrP(Or=1.089, P=0.013) and ALT(Or=1.010, P=0.034) were statistically significant independent predictors of dengue ***: CrP level could be used as a potential biomarker to predict severity of dengue in adults.

关键词： Vector-borne Arbovirus Inflammation Biochemical Tropical disease

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Effect of ultrasonic assisted sintering on mechanical properties and degradation behaviour of Mg15Nb3Zn1Ca biomaterial

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Journal of Magnesium and Alloys 2021年第6期9卷 1989-2008页

作者： Ajit kumar Pulak M pandey Department of Mechanical Engineering Indian Institute of TechnologyDelhiNew Delhi 110016India

The present work investigates the effect of ultrasonic power(%)and the time of ultrasonic vibration on the sintered density and ultimate compressive strength(UCS)of Mg15Nb3Zn1Ca fabricated using ultrasonic assisted conventional sintering(UACS).The customized UACS setup was designed and manufactured to conduct the experimentations.A customized ultrasonic stepped horn assembly was used for providing vibrations to the sample during ***,to evaluate the efficacy of ultrasonic vibration parameters,the developed setup was used to sinter Mg15Nb3Zn1Ca composite *** study unveiled an increased sintered density and UCS of the fabricated sample by the increase in ultrasonic power(%).Moreover,a decrease in sintered density and UCS was observed with an increase in the time of ultrasonic vibration beyond a certain *** sintered with the assistance of ultrasonic vibration at 100%ultrasonic power,and 20 min of ultrasonic vibration resulted in a sintered density of 1.928±0.062 g·cm^(-3)and UCS of 234.9±12.3 *** obtained mechanical properties of the fabricated sample were comparable to the properties of cortical *** surface morphology and elemental compositions of samples fabricated using UACS declared a fair dispersion of reinforcement in the matrix containing merely the source *** results of corrosion test have showed that the assistance of ultrasonic vibration suppressed the degradation behaviour of the sintered sample after performing electrochemical study of samples using 3-electorde cell ***15Nb3Zn1Ca fabricated using UACS showed a 50.18%and 9.08%of reduction in corrosion rate over conventionally sintered pure Mg and Mg15Nb3Zn1Ca *** addition,electrochemical impedance spectroscopy(EIS)results indicated an enhanced corrosion resistance of the Mg15Nb3Zn1Ca composite material when fabricated at 100%of ultrasonic power with 20 min of vibration *** from that,electrochemical equivalent circuits also result

关键词： Ultrasonic assisted sintering Magnesium Corrosion EIS Mechanical properties

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Can we constrain the evolution of HI bias using configuration entropy?

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research in Astronomy and Astrophysics 2021年第2期21卷 82-88页

作者： Biswajit Das Biswajit pandey Department of Physics Visva-Bharati UniversitySantiniketanBirbhum731235India

We study the evolution of the configuration entropy of HI distribution in the post-reionization era assuming different time evolution of HI *** describe time evolution of linear bias of HI distribution using a simple form b(a)=b_(0)a^(n) with different index *** derivative of the configuration entropy rate is known to exhibit a peak at the scale factor corresponding to theΛ-matter equality in the unbiasedΛCDM *** show that in theΛCDM model with time-dependent linear bias,the peak shifts to smaller scale factors for negative values of *** is related to the fact that the growth of structures in the HI density field can significantly slow down even before the onset ofΛdomination in the presence of a strong time evolution of the HI *** find that the shift is linearly related to the index *** obtain the best fit relation between these two parameters and propose that identifying the location of this peak from observations would allow us to constrain the time evolution of HI bias within the framework of theΛCDM model.

关键词： methods analytical-cosmology theory-large scale structure of the universe

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A New Stable Algorithm to Compute Hankel Transform Using Chebyshev Wavelets

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Communications in Computational Physics 2010年第7期8卷 351-373页

作者： rajesh k.pandey Vineet k.Singh Om P.Singh PDPM Indian Institute of Information Technology Design and Manufacturing JabalpurIndia Birla Institute of Technology and Science-Pilani Goa CampusGoaIndia Department of Applied Mathematics Institute of TechnologyBanaras Hindu UniversityVaranasiIndia

A new stable numerical method,based on Chebyshev wavelets for numerical evaluation of Hankel transform,is proposed in this *** Chebyshev wavelets are used as a basis to expand a part of the integrand,r f(r),appearing in the Hankel transform *** transforms the Hankel transform integral into a Fourier-Bessel *** truncating the series,an efficient and stable algorithm is obtained for the numerical evaluations of the Hankel transforms of order ν>−*** method is quite accurate and stable,as illustrated by given numerical examples with varying degree of random noise terms εθ_(i) added to the data function f(r),where θ_(i) is a uniform random variable with values in[−1,1].Finally,an application of the proposed method is given for solving the heat equation in an infinite cylinder with a radiation condition.

关键词： Hankel transforms Bessel functions Chebyshev wavelets random noise term

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Alkaline phosphatase as a bio-indicator of phosphorus-eutrophy in freshwater ecosystems: A review

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International Journal of Sediment research 2023年第3期38卷 349-360页

作者： Madhulika Singh Jitendra pandey Ganga river Ecology research Laboratory Environmental Science Division Centre of Advanced Study in Botany Institute of Science Banaras Hindu University

Limnologists have greatly advanced the understanding of indicators of phosphorus(P)-eutrophy in surface waters. Biotic variables such as macro-invertebrates, fish, zooplankton, benthic algae, and diatoms are extensively used for bio-assessment of eutrophy. New concepts highlight the importance of bed-sediment based “response” variables predicting functional shifts during eutrophication. A cross analysis of studies reveals that alkaline phosphatase(ALP), which serves as a proxy of P-deficiency, and also as an indicator of benthic anoxia/hypoxia-driven feedbacks, can be an easy to measure, cost-effective and reliable tool to assess changes in nutrient stoichiometry, trophic status, and ecological functioning at the sediment-water interface. Here, the issues discussed in this paper are highly relevant to explore new domains of research and “response” based ecosystem models for potential eutrophication management decisions. Because ALP is used in molecular cloning and fingerprinting studies, it is suggested that approaches based on the “omics” technologies need to be used to explore more intricate connections to empirically address ALP-P-eutrophy linkages to track eutrophication in freshwater ecosystems.

关键词： Alkaline phosphatase Sediment based-indicators Ecosystem feedback Nutrient stoichiometry Phosphorus-eutrophy

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Preparation,characterization and thermophysical properties investigation of A70/polyaniline nanocomposite phase change material for medium temperature solar applications

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能源与人工环境(英文) 2021年第3期2卷 271-277页

作者： A.k.pandey Mathew George Nasrudin Abd rahim V.V.Tyagi Syed Shahabuddin r.Saidur research Centre for Nano-Materials and Energy Technology(rCNMET) School of Science and TechnologySunway UniversityNo.5Jalan UniversitiBandar SunwayPetaling Jaya47500 Selangor Darul EhsanMalaysia Higher Institution Centre of Excellence(HICoE) UM Power Energy Dedicated Advanced Centre(UMPEDAC)Level 4Wisma R&DUniversity of MalayaJalan Pantai Baharu59990 Kuala LumpurMalaysia renewable Energy research Group King Abdulaziz UniversityJeddah 21589Saudi Arabia School of Energy Management Shri Mata Vaishno Devi UniversityKatra 182320(J&K)India Department of Science School of TechnologyPandit Deendayal Petroleum UniversityKnowledge CorridorRaisan VillageGandhinagar 382007GujratIndia

The ever-present demand for energy from various application in industrial and domestic processes has led to the consumption of fossil fuel at a rapid rate with adverse effect due to global *** study focuses on the thermal energy storage aspect intended for medium temperature applications.A novel composite A70 and PANI was prepared and *** study investigates the composites thermophysical and optical *** Scanning Calorimetry and Transient Hot Bridge measured thermal storage capacity and thermal conductivity of the composite,*** heat storage capacity of the composite remained stable within 4%whereas a highest rise of 11.96%in thermal conductivity was *** composites thermal,chemical,and physical stability were analysed from Thermogravimetric Analyser,Fourier Infrared Transform,and Scanning Electron Microscope,*** composites were thermally stable up to a temperature of 250°*** chemical reaction occurred between the nanomaterial and base PCM *** microscopic visuals did not show any considerable change in the microscopic structure of the *** the case of optical properties,the composites showed significant reduction in transmittance of solar spectrum with respect to pure *** maximum decrement in transmission was around~89%compared to *** the composite prepared were thermally stable till 250°C,hence may be utilized for solar thermal and low concentrated photovoltaic application but not limited to these.

关键词： Phase change materials Solar energy Thermal conductivity Latent heat Polyaniline

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Exploration of deep seabed polymetallic sulphides: Scientific rationale and regulations of the International Seabed Authority

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矿业科学技术学报：英文版 2013年第3期23卷 457-462页

作者： Anju pandey Ministry of Earth Sciences Prithvi Bhavan New Delhi 110003 India

Polymetallic sulphides have been consistent source of metals like iron, copper, zinc and lead. Apart from these they are also seen as economically viable resources of silver and gold. As the demand of these metals is showing an astoundingly increasing trend, the search for their resources has also increased in similar folds. This has resulted in many nations' focus on deep seabed resources of the polymetallic sulphides. Consequently, International Seabed Authority (ISBA) has provided 'regulations' to obtain plan of work for exploration of polymetallic sulphide deposits in deep seabed 'Area'. Following the release of these regulations, several countries are in the process of obtaining the licence for exploration of these metals from the deep seabed regions. Detailed information about the science and ISBA regulations for exploration of polymetallic sulphide deposits is prerequisite to submit an application to ISBA for their exploration. The current contribution provides a comprehensive review of the science behind locating polymetallic sulphide deposits in geological setting of deep seabed as well as about the ISBA regulations for their exploration.

关键词： Polymetallic sulphide International Seabed Authority Exploration Mid ocean ridges

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A multiwavelength view of a classical T Tauri star CV Cha

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research in Astronomy and Astrophysics 2019年第1期19卷 75-86页

作者： Jeewan Chandra pandey Subhajeet karmakar Arti Joshi Saurabh Sharma Shashi Bhushan pandey Anil kumar pandey Aryabhatta research Institute of Observational Sciences (ArIES)

Using long-term optical, ultraviolet(UV) and X-ray data, we present a study of a classical T Tauri star CV Cha. The V-band light curve obtained from the All Sky Automated Survey(ASAS) shows short as well as long-term variability. The short-term variability could be due to rotational modulation of CV Cha. We derive the rotational period of 3.714 ± 0.001 d for CV Cha. UV light curves obtained from Swift also show the variations. X-ray light curves from XMM-Newton and Swift do not show any significant short as well as long-term variability. However, the light curve from Chandra appears to be variable, which could be due to the emergence of flaring activities. X-ray spectra from all observations are explained well by the single temperature plasma of 0.95 keV with X-ray luminosity of 1030.4erg s-1in the 0.5–7.5 keV energy band. It appears that variability in optical and UV bands could be due to the presence of both hot and cool spots on the surface, while X-ray emission is dominated by magnetic processes.

关键词： stars:activity stars:individual(CV Cha) stars:pre-main sequence stars:variable:T Tauri X-ray:stars

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