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Systematic analysis of low/hard state RXTE spectra of GX 339–4 to constrain the geometry of the system

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Research in Astronomy and Astrophysics 2018年第5期18卷 37-46页

作者： kalyani Bagri Ranjeev Misra Anjali Rao Jagdish singh Yadav shiv kumar Pandey Pt. Ravishankar Shukla University Raipur Chhattisgard 492010 India Inter-University Centre for Astronomy and Astrophysics Ganeshkhind Pune 411007 India Tata Institute of Fundamental Research Colaba Mumbai 400005 India

One of the popular models for the low/hard state of black hole binaries is that the standard accretion disk is truncated and the hot inner region produces, via Comptonization, hard X-ray *** is supported by the value of the high energy photon index, which is often found to be small,～ 1.7（〈 2）, implying that the hot medium is starved of seed photons. On the other hand, the suggestive presence of a broad relativistic Fe line during the hard state would suggest that the accretion disk is not truncated but extends all the way to the innermost stable circular orbit. In such a case, it is a puzzle why the hot medium would remain photon starved. The broad Fe line should be accompanied by a broad smeared reflection hump at ～ 30 ke V and it may be that this additional component makes the spectrum hard and the intrinsic photon index is larger, i.e. 〉2. This would mean that the medium is not photon deficient, reconciling the presence of a broad Fe line in the observed hard state. To test this hypothesis,we have analyzed the RXTE observations of GX 339–4 from the four outbursts during 2002–2011 and identify observations when the system was in the hard state and showed a broad Fe line. We have then attempted to fit these observations with models, which include smeared reflection, to understand whether the intrinsic photon index can indeed be large. We find that, while for some observations the inclusion of reflection does increase the photon index, there are hard state observations with a broad Fe line that have photon indices less than 2.

关键词： accretion accretion disks - stars black holes - X-rays binaries - X-rays individual(GX 339-4)

A Weakly Supervised Deep Learning Framework for Sorghum Head Detection and Counting

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Plant Phenomics 2019年第1期1卷 1-14页

作者： Sambuddha Ghosa Bangyou Zheng Scott Chapman Andries B.Potgieter David R.Jordan Xuemin Wang Asheesh k.singh Arti singh Masayuki Hirafuji Seishi Ninomiya Baskar Ganapathysubramanian Soumik Sarkar Wei Guo Department of Mechanical Engineering Iowa State UniversityAmesIAUSA Department of Computer Science Iowa State UniversityAmesIAUSA CSIRO Agriculture and Food St.LuciaQLDAustralia School of Agriculture and Food Sciences The University of QueenslandGattonQLD 4343Australia Queensland Alliance for Agriculture and Food Innovation(QAAFI) The University of QueenslandGattonQLDAustralia Queensland Alliance for Agriculture and Food Innovation(QAAFI) The University of QueenslandWarwickQLDAustralia Department of Agronomy Iowa State UniversityAmesIAUSA International Field Phenomics Research Laboratory Institute for Sustainable Agro-Ecosystem Services

The yield of cereal crops such as sorghum(Sorghum bicolor ***)depends on the distribution of crop-heads in varying branching ***,counting the head number per unit area is critical for plant breeders to correlate with the genotypic variation in a specific breeding ***,measuring such phenotypic traitsmanually is an extremely labor-intensive process and suffers from low efficiency and human ***,the process is almost infeasible for large-scale breeding plantations or *** learning-based approaches like deep convolutional neural network(CNN)based object detectors are promising tools for efficient object detection and ***,a significant limitation of such deep learningbased approaches is that they typically require a massive amount of hand-labeled images for training,which is still a tedious ***,we propose an active learning inspired weakly supervised deep learning framework for sorghum head detection and counting from UAV-based *** demonstrate that it is possible to significantly reduce human labeling effort without compromising final model performance(R^(2)between human count and machine count is 0.88)by using a semitrained CNN model(i.e.,trained with limited labeled data)to perform synthetic *** addition,we also visualize key features that the network *** improves trustworthiness by enabling users to better understand and trust the decisions that the trained deep learning model makes.

关键词： Unmanned aerial vehicles (UAV)

Current therapeutic modalities and chemopreventive role of natural products in liver cancer:Progress and promise

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World Journal of Hepatology 2023年第1期15卷 1-18页

作者： Amit kumar singh shiv Vardan singh Ramesh kumar Shashank kumar Sabyasachi Senapati Abhay k Pandey Department of Botany Government Naveen Girls CollegeBalod(Hemchand Yadav University)DurgChattisgarhIndia Department of Biochemistry University of AllahabadPrayagraj 211002Uttar PradeshIndia Department of Biochemistry School of Basic and Applied SciencesCentral University of PunjabBathinda 151401PunjabIndia Department of Human Genetics and Molecular Medicine Central University of PunjabBathinda 151401PunjabIndia

Liver cancer is a severe concern for public health officials since the clinical cases are increasing each year,with an estimated 5-year survival rate of 30%–35%after *** carcinoma(HCC)constitutes a significant subtype of liver cancer(approximate75%)and is considered primary liver *** for liver cancer mainly depends on the stage of its progression,where surgery including,hepatectomy and liver transplantation,and ablation and radiotherapy are the prime *** advanced liver cancer,various drugs and immunotherapy are used as first-line treatment,whereas second-line treatment includes chemotherapeutic drugs from natural and synthetic *** and lenvatinib are first-line therapies,while regorafenib and ramucirumab are secondline *** metabolic and signaling pathways such as Notch,JAk/STAT,Hippo,TGF-β,and Wnt have played a critical role during HCC *** has also been implicated in liver ***-induced toxicity is a key obstacle in the treatment of liver cancer,necessitating the development of effective and safe medications,with natural compounds such as resveratrol,curcumin,diallyl sulfide,and others emerging as promising anticancer *** review highlights the current status of liver cancer research,signaling pathways,therapeutic targets,current treatment strategies and the chemopreventive role of various natural products in managing liver cancer.

关键词： Liver cancer Hepatocellular carcinoma Signaling pathways Therapeutic targets Natural products Chemopreventive

key microorganisms mediate soil carbon-climate feedbacks in forest ecosystems

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Science Bulletin 2021年第19期66卷 2036-2044,M0004页

作者： Jinquan Li Ting Zhu Brajesh k.singh Elise Pendall Bo Li Changming Fang Ming Nie National Observations and Research Station for Wetland Ecosystems of the Yangtze Estuarine and Ministry of Education Key Laboratory for Biodiversity Science and Ecological EngineeringInstitute of Biodiversity ScienceSchool of Life SciencesFudan UniversityShanghai 200438China Hawkesbury Institute for the Environment Western Sydney UniversityPenrith NSW 2751Australia Global Centre for Land-Based Innovation Western Sydney UniversityPenrith NSW 2751Australia

Soil microorganisms are known to significantly contribute to climate change through soil carbon(C)cycle ***,it is challenging to incorporate these feedbacks into predictions of future patterns of terrestrial C cycling,largely because of the vast diversity of soil microorganisms and their responses to environmental ***,we show that the composition of the bacterial community can provide information about the microbial community-level thermal response(MCTR),which drives ecosystemscale soil C-climate *** dominant taxa from 169 sites representing a gradient from tropical to boreal forest mainly belonged to the phyla Actinobacteria and ***,we show that the MCTR in warm biomes and acidic soils was linked primarily to bacteria,whereas the MCTR in cold biomes and alkaline soils was primarily associated with *** results provide strong empirical evidence of linkages between microbial composition and the MCTR across a wide range of forests,and suggest the importance of specific microorganisms in regulating soil C-climate feedbacks.

关键词： Soil respiration Temperature sensitivity key microorganisms Microbial community Climate warming

Effect of induced magnetic field on natural convection in vertical concentric annuli

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Acta Mechanica Sinica 2012年第2期28卷 315-323页

作者： R.k.singh A.k.singh Department of Mathematics Central University of BiharPatnaIndia Department of Mathematics Banaras Hindu UniversityVaranasiIndia

In the present paper, we have considered the steady fully developed laminar natural convective flow in open ended vertical concentric annuli in the presence of a ra- dial magnetic field. The induced magnetic field produced by the motion of an electrically conducting fluid is taken into account. The transport equations concerned with the con- sidered model are first recast in the non-dimensional form and then unified analytical solutions for the velocity, induced magnetic field and temperature field are obtained for the cases of isothermal and constant heat flux on the inner cylin- der of concentric annuli. The effects of the various phys- ical parameters appearing into the model are demonstrated through graphs and tables. It is found that the magnitude of maximum value of the fluid velocity as well as induced magnetic field is greater in the case of isothermal condition compared with the constant heat flux case when the gap be- tween the cylinders is less or equal to 1.70 times the radius of inner cylinder, while reverse trend occurs when the gap between the cylinders is greater than 1.71 times the radius of inner cylinder. These fields are almost the same when the gap between the cylinders is equal to 1.71 times the radius of inner cylinder for both the cases. It is also found that as the Hartmann number increases, there is a flattening ten- dency for both the velocity and the induced magnetic field. The influence of the induced magnetic field is to increase the velocity profiles.

关键词： Natural convection Isothermal Heat flux Skin-friction Induced magnetic field Magnetohydrody- namics

Molecular signalling during cross talk between gut brain axis regulation and progression of irritable bowel syndrome:A comprehensive review

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World Journal of Clinical Cases 2023年第19期11卷 4458-4476页

作者： shiv Vardan singh Risha Ganguly kritika Jaiswal Aditya kumar Yadav Ramesh kumar Abhay k Pandey Department of Biochemistry University of AllahabadAllahabad(Prayagraj)211002Uttar PradeshIndia

Irritable bowel syndrome(IBS)is a chronic functional disorder which alters gastrointestinal(GI)functions,thus leading to compromised health *** of IBS is not fully understood,whereas abnormal gut brain axis(GBA)has been identified as a major etiological *** studies are suggestive for visceral hyper-sensitivity,altered gut motility and dysfunctional autonomous nervous system as the main clinical abnormalities in IBS *** signalling interactions among these abnormalities are derived through various exogenous and endogenous factors,such as microbiota population and diversity,microbial metabolites,dietary uptake,and psychological *** efforts focused to study these interactions including probiotics,antibiotics and fecal transplantations in normal and germfree animals are clearly suggestive for the pivotal role of gut microbiota in IBS ***,neurotransmitters act as communication tools between enteric microbiota and brain functions,where serotonin(5-hydroxytryptamine)plays a key role in pathophysiology of *** regulates GI motility,pain sense and inflammatory responses particular to mucosal and brain *** the absence of a better understanding of various interconnected crosstalks in GBA,more scientific efforts are required in the search of novel and targeted therapies for the management of *** this review,we have summarized the gut microbial composition,interconnected signalling pathways and their regulators,available therapeutics,and the gaps needed to fill for a better management of IBS.

关键词： Irritable bowel syndrome Microbiota Gut brain axis Stress Serotonin

Elemental variations in glacier cryoconites of Indian Himalaya and Spitsbergen,Arctic

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作者： Ajay k.singh原

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Geoscience Frontiers 2017年第6期8卷 1339-1347页

作者： shiv Mohan singh kumar Avinash Parmanand Sharma Ravindra Uttam Mulik Ajay kumar Upadhyay Rasik Ravindra Earth System Science Organisation National Centre for Antarctic and Ocean ResearchHeadland SadaGoa403804India National Research Centre for Grapes Pune412307India Ministry of Earth Sciences Prithvi BhavanIMD CampusOpp.India Habitat CentreLodi RoadNew Delhi110003India

Cryoconite samples were collected from two different climatic domains i.e.,the Sutri Dhaka glacier,western Himalaya India and Svalbard glaciers,the Spitsbergen,Arctic,to understand the elemental source and elemental deposition *** data of geochemical analysis suggest that the Himalayan cryoconite samples accumulate higher concentrations as compared to the cryoconite samples of the Arctic *** concentration of lithophile elements(Cs,Li,Rb and U)was recorded higher in the cryoconite holes of the Himalayas,especially,in the lower to the higher parts of the glacier,whereas,lower concentrations were recorded in the Arctic *** elements in the Himalayan cryoconites are enriched in As and Bi while the Arctic cryoconite samples show a higher concentration of Bi,Pb and *** higher concentrations are responsible for influencing the ecosystem and in human health related *** elements(Co,Fe,Mn and Ni)show high concentrations in the Himalayan samples,whereas,the Arctic samples show minor variations and low elemental concentration in these elements,*** addition,a few elements,such as Ag,Mg,and Ca show higher concentration in the Himalayan glacier *** also occurs in high concentrations in Arctic glacier samples.R-mode factor analysis of the Himalayas(Arctic)samples indicate that the elements are distributed in four(three)factors,explaining 89%(90%)of the variance in their elemental *** Factor 1 suggests statistically significant positive loadings for most of the lithophile,chalcophile and siderophile elements of the "Himalayan" and the Arctic cryoconite *** sample-wise factor score distribution shows a considerable variation in the sampling locations along the glaciers of both the *** 2 and 3,demonstrate insignificant loading for most of the elements,except statistically significant positive loading in some of the elements of the both,Himalayan and Arctic "cryoconites".The higher el

关键词： Cryoconite Elemental concentration Factor analyses Himalaya Spitsbergen

Micronization enhanced extractability of polyphenols and anthocyanins in tart cherry puree

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Food Bioscience 2022年第6期50卷 676-684页

作者： Nishtha Lukhmana Fanbin kong Rakesh k.singh Department of Food Science and Technology The University of Georgia100 Cedar StreetAthensGA30602-2610USA

Tart cherries(Prunus cerasus L.)are the richest in phenolic compounds,among all the members of drupe family of *** reduce the inherent sourness of the cherries,thermal processing or filtration steps are *** processes lead to changes in pH,and exposure to temperature enhances oxidation leading to degradation of *** the present study,Megatron®and high-pressure homogenization(HPH)were employed to produce micronized puree,which was analyzed for polyphenolic,flavonoid and anthocyanin contents using various *** methods of micronization lead to breakage of cell wall structure facilitating enhanced release of bioactives from the cellular matrix and thus higher antioxidant *** presence of functional groups was corroborated by FTIR spectrophotometric analysis,and reversed phase HPLC for the presence and relative amounts of various polyphenols and *** was a significant increase(p<0.05)of in the extractability of polyphenols with HPH(285.05 GAEμg/g)in comparison with the non-micronized samples(166.80 GAEμg/g).The changes in anthocyanins and flavonoids were also significant(p<0.05),thus confirming the impact of micronization on the antioxidant release in tart cherries.

关键词： Particle size Antioxidants Polyphenols High-pressure homogenization Bioaccessibility