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photon orbits and phase transition for Letelier AdS black holes immersed in perfect fluid dark matter

Chinese physics C 2024年第6期48卷 247-259页

作者： Ashima Sood Md Sabir Ali J.K.singh Sushant G.Ghosh Department of Mathematics Netaji Subhas University of TechnologyNew Delhi-110078India Centre for Theoretical physics Jamia Millia IslamiaNew Delhi 110025India Department of physics Mahishadal Raj CollegePurba MedinipurWest Bengal721628India Institute of Theoretical physics&Research Center of Gravitation Lanzhou UniversityLanzhou 730000China Key Laboratory of Quantum Theory and Applications of MoE Lanzhou UniversityLanzhou 730000China Lanzhou Center for Theoretical physics&Key Laboratory of Theoretical physics of Gansu province Lanzhou UniversityLanzhou 730000China Astrophysics and Cosmology Research Unit School of MathematicsStatistics and Computer ScienceUniversity of KwaZulu-NatalPrivate Bag X54001Durban 4000South Africa

We obtain an exact solution for spherically symmetric Letelier AdS black holes immersed in perfect fluid dark matter(pFDM).Considering the cosmological constant as the positive pressure of the system and volume as its conjugate variable,we analyze the thermodynamics of our black holes in the extended phase *** to the background clouds of strings parameter(a)and the parameter endowed with pFDM(β),we analyze the Hawking temperature,entropy,and specific ***,we investigate the relationship between the photon sphere radius and phase transition for the Letelier AdS black holes immersed in *** the analysis,with a particular condition,non-monotonic behaviors are found between the photon sphere radius,impact parameter,pFDM parameter,temperature,and *** can regard the changes in both the photon sphere radius and impact parameter before and after phase transition as the order parameter;their critical exponents near the critical point are equal to the same value,1/2,similar to that in ordinary thermal *** indicates that a universal relation of gravity may exist near the critical point for a black hole thermodynamic system.

关键词： AdS black holes perfect fluid dark matter Letelier spacetime photon orbit extended phase space thermodynamics correlation of photon orbit and thermodynamics

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Influence of edaphic factors on distribution and condition of Himalayan silver birch(betula utilis ***)communities in the northwestern Indian Himalayas

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Journal of Mountain Science 2024年第2期21卷 590-606页

作者： Khashti DASILA Renu RAWAL Tanay bARMAN Sher singh SAMANT Anita pANDEY Veena pANDE G.b.p.nt National Institute of Himalayan Environment Almora 263643India Centre of Excellence on Sustainable Land Management Indian Council of Forestry Research and EducationDehradun 248006India Uttarakhand State Council for Science&Technology Dehradun 248015India Department of biotechnology Graphic Era(Deemed to be University)Dehradun 248002India Department of biotechnology Kumaun UniversityNainital 263136India

The basic concept of phytosociology is crucial for the assessment of species composition and dynamic ecological succession of forests supporting ecological services,functions,disturbance,and resilience that lead to the development of integrated areas such as ecological niche modeling and contribute to identifying the valuable bio-indicators which can be used in framing conservation and management *** is one of the most dominant tree species of treeline ecotone in the Himalayan *** species is also considered as indicator species for monitoring the past and recent climate change *** current study was carried out in the natural populations of *** from the sub-alpine zone of North-western Indian *** birch dominated forest harbors a total of 305 plant species comprising Angiosperms(51 families,160 genera and 277 species),Gymnosperms(03 families,05 genera and 07 species)and pteridophytes(07 families,11 genera and 21 species)with Asteraceae,Ranunculaceae and Rosaceae as dominant *** forests are found dominant in shady moist habitat and North West *** characteristics,anthropogenic and developmental activities affect the population structure of *** and associated ***,the species has fair regeneration status in the study *** acidic nature of soil pH and spatial variation in edaphic characteristics may be due to geographical differences,rooting patterns and litter accumulation of below and above-ground *** estimation of a representative population of *** from each site showed that TAGbD,TCD and TbD were found maximum in ST3(Hamta pass II site).The CCA analysis determined that environmental variables such as altitude,organic matter,available phosphorous,organic carbon,available nitrogen,and electrical conductivity played a significant role in determining tree species composition and distribution in *** dominated forests.

关键词： Species composition Indicator species biomass North-western Indian Himalaya Regeneration Environmental variables

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prediction of rock fragmentation in a fiery seam of an open-pit coal mine in India

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 2879-2893页

作者： Mukul Sharma bhanwar singh Choudhary Autar K.Raina Manoj Khandelwal Saurav Rukhiyar Department of Mining Engineering Indian Institute of Technology(ISM)Dhanbad826004India CSIR-Central Institute of Mining and Fuel Research Nagpur Research Center(Mining Technology)Nagpur440006India Institute of Innovation Science and SustainabilityFederation University AustraliaBallaratVIC3350Australia

Spontaneous combustion of coal increases the temperature in adjoining overburden strata of coal seams and poses a challenge when loading *** condition,known as hot-hole blasting,is dangerous due to the increased possibility of premature explosions in loaded ***,it is crucial to load the blastholes with an appropriate amount of explosives within a short period to avoid premature detonation caused by high temperatures of ***,it will help achieve the desired fragment *** study tried to ascertain the most influencial variables of mean fragment size and their optimum values adopted for blasting in a fiery *** on blast design,rock mass,and fragmentation of 100 blasts in fiery seams of a coal mine were collected and used to develop mean fragmentation prediction models using soft computational *** coefficient of determination(R^(2)),root mean square error(RMSE),mean absolute error(MAE),mean square error(MSE),variance account for(VAF)and coefficient of efficiency in percentage(CE)were calculated to validate the *** indicates that the random forest algorithm(RFA)outperforms the artificial neural network(ANN),response surface method(RSM),and decision tree(DT).The values of R^(2),RMSE,MAE,MSE,VAF,and CE for RFA are 0.94,0.034,0.027,0.001,93.58,and 93.01,*** parametric sensitivity analyses(MpSAs)of the input variables showed that the Schmidt hammer rebound number and spacing-to-burden ratio are the most influencial variables for the blast fragment *** analysis was finally used to define the best blast design variables to achieve optimum fragment size from *** optimum factor values for RFA of S/b,ld/b and ls/ld are 1.03,1.85 and 0.7,respectively.

关键词： Fiery seam Rock fragmentation Response Surface Method(RSM) Artificial Neural Network(ANN) Random Forest Algorithm(RFA) Multiple parametric Sensitivity Analysis (MpSA)

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Variation in the Flaring potential of Different Sunspot Groups During Different phases of Solar Cycles 23 and 24

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Research in Astronomy and Astrophysics 2024年第2期24卷 144-153页

作者： Abha singh Anurag Chaudhari Gyaneshwar Sharma A.K.singh Department of physics T.D.P.G.College Jaunpur-222002India Department of physics Banaras Hindu UniversityVaranasi-221005India

In this present study,we have analyzed different types of X-ray solar flares(C,M,and X classes)coming out from different classes of sunspot groups(SSGs).The data which we have taken under this study cover the duration of 24 yr from 1996 to *** this,we observed a total of 15015 flares(8417 in SC-23 and 6598 in SC-24)emitted from a total of 33780 active regions(21746 in SC-23 and 12034 in SC-24)with sunspot *** defined the flaring potential or flare-production potential as the ratio of the total number of flares produced from a particular type of SSG to the total number of the same-class SSGs observed on the solar *** we studied yearly changes in the flaring potential of different McIntosh class groups of sunspots in different phases of SC-23 and *** addition,we investigated yearly variations in the potential of producing flares by different SSGs(A,b,C,D,E,F,and H)during different phases(ascending,maximum,descending,and minimum)of SC-23 and *** are our findings:(1)D,E,and F SSGs have the potential of producing flares≥8 times greater than A,b,C and H SSGs;(2)The larger and more complex D,E,and F SSGs produced nearly 80%of flares in SC-23 and 24;(3)The A,b,C and H SSGs,which are smaller and simpler,produced only 20%of flares in SC-23 and 24;(4)The biggest and most complex SSGs of F-class have flaring potential 1.996 and 3.443 per SSG in SC-23 and 24,respectively.(5)The potential for producing flares in each SSG is higher in SC-24 than in SC-23,although SC-24 is a weaker cycle than SC-23.(6)The alterations in the number of flares(C+M+X)show different time profiles than the alterations in sunspot numbers during SC-23 and 24,with several peaks.(7)The SSGs of C,D,E,and H-class have the highest flaring potential in the descending phase of both SC-23 and 24.(8)F-class SSGs have the highest flaring potential in the descending phase of SC-23 but also in the maximum phase of SC-24.

关键词： (Sun:)sunspots-Sun flares-Sun activity-Sun magnetic fields-Sun filaments-prominences

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Vegetative propagation of Dalbergia sissoo:effect of growth regulators,length,position of shoot and type of cuttings on rooting potential in stem cuttings

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Forestry Studies in China 2012年第3期14卷 187-192页

作者： bhupendra singh Rajendra YADAV b.p. bHATT Department of Forestry H.N.B.Garhwal UniversitySrinagar (Garhwal)Uttarakhand 246174India Chhattisgarh Minor Forest produce Federation A-25VIP EstateKhamhardihShankar NagarRaipur 492007India ICAR Research Complex for Eastern Region PatnaBihar 800014India

The effect of auxins （IAA or IbA at 100, 200, 500 mg.L J） on rooting and sprouting parameters differed significantly （p 〈 0.05）. Rooting and sprouting percentages were higher in some treatments while other parameters were significantly higher in other treatments. The results of the present study revealed that rooting was significantly （p 〈 0.05） affected by the length of cuttings, as well as the position of shoots and type of cuttings. On average, 86.0 per cent rooting was observed in the 30-cm long cuttings com- pared to the other two lengths of cuttings, i.e., 20 and 25 cm, irrespective of any auxin treatment. In a control set, without any auxin treatment, a maximum of 60.0% rooting was recorded in the 30-cm long cuttings and a minimum of 40.0% of the cuttings rooted in the 20-cm long cuttings. Similarly, cuttings collected from the lower and upper portions of shoots resulted in 72.5 and 52.5 per cent rooting respectively, irrespective of auxin treatments. Maximum rooting was observed in the lower portion （40.0%） of cutting com- pared to the upper portion （30.0%） in the control set without auxin treatment. Leafless branches produced maximum （72.0%） rooting compared to the leafy cuttings （35.0%）, irrespective of the auxin treatment. The leafy cuttings produces a minimum of 15.0% sprout- ing and rooting in the control set.

关键词： auxin Dalbergia sissoo length position of shoots type of cuttings vegetative propagation

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Experimental and Finite Element Analysis of Corroded High-pressure pipeline Repaired by Laminated Composite

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Computer Modeling in Engineering & Sciences 2024年第8期140卷 1783-1806页

作者： Seyed Mohammad Reza Abtahi Saeid Ansari Sadrabadi Gholam Hosein Rahimi Gaurav singh Hamid Abyar Daniele Amato Luigi Federico Faculty of Mechanical Engineering Tarbiat Modares UniversityTehran***Iran A.Leon Linton Department of Mechanical Robotics and Industrial EngineeringLawrence Technological UniversitySouthfieldMI48075USA Department of Mechanical Engineering Faculty of EngineeringMeybod UniversityYazd***Iran Department of Industrial Engineering University of SalernoVia Giovanni PaoloⅡFiscianoItaly Italian Aerospace Research Center(C.I.R.A.) Via MaioriseCapuaCE81043Italy

Repairs of corroded high-pressure pipelines are essential for fluids transportation under high *** of the methods used in their repairs is the use of layered *** composite used must have the necessary ***,the experiments and analytical solutions presented in this paper are performed according to the relevant standards and codes,including ASME pCC-2,ASME b31.8S,ASME b31.4,ISO 24817 and ASME *** addition,the experimental tests are replicated numerically using the finite element *** the strain gauges at different distances from the defect location,can reduce the nonlinear effects,deformation,and fluctuations due to the high *** direct relationship between the depth of an axial defect and the stress concentration is observed at the inner side edges of the *** reparation reduces the non-linearities related to the sharp variation of the geometry and a more reliable numerical simulation could be performed.

关键词： High-pressure pipeline composite repair ASME pCC-2 ISO 24817

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高速火焰喷涂VC-CuNiCr涂层的耐腐蚀性能

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Journal of Central South University 2024年第5期31卷 1385-1397页

作者： singh Vikrant bANSAL Anuj SINGLA Anil Kumar KUMAR Vijay Sant Longowal Institute of Engineering and Technology Longowal Sangrur 148106India Industrial and production Engineering Department Dr B R Ambedkar National Institute of TechnologyJalandhar 144011India

本研究采用高速火焰喷涂(HVOF)沉积技术,将碳化钒(VC)和铜镍铬(CuNiCr)复合涂层应用于SS316不锈钢上,以解决不锈钢在海洋环境中的腐蚀问题。在室温环境下,在3.5%氯化钠溶液中进行电化学腐蚀,通过扫描电子显微镜(SEM)和能量色散光谱(EDS... 详细信息

本研究采用高速火焰喷涂(HVOF)沉积技术,将碳化钒(VC)和铜镍铬(CuNiCr)复合涂层应用于SS316不锈钢上,以解决不锈钢在海洋环境中的腐蚀问题。在室温环境下,在3.5%氯化钠溶液中进行电化学腐蚀,通过扫描电子显微镜(SEM)和能量色散光谱(EDS)对有涂层和未覆涂层样品的表面形貌进行检测。结果表明,涂层内由铜(Cu)、镍(Ni)和铬(Cr)组成的金属间黏合剂在氯化钠介质的影响下发生变质,从而导致出现衬底间的局部点蚀现象。有趣的是,在涂层配方中加入碳化钒(VC)显著地增强了表面的耐腐蚀性能,从而阻止了密闭腐蚀凹坑的出现。在不同类的涂层中,加入VC的效果最好,最小的腐蚀速率为72.38×10^(-3)mm/a,相比之下,SS316基底的腐蚀速率最快。

关键词：高速火焰喷涂碳化钒铜镍铬电化学腐蚀氯化钠溶液

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parents’s knowledge and awareness about hepatitis b can influence the vaccination of their children

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World Journal of Virology 2024年第2期13卷 96-106页

作者： Nanda Chhavi Geetika Srivastava Mariya Waseem Abhishek Yadav Surender singh Rajani singh Amit Goel Department of paediatrics Era’s Lucknow Medical CollegeLucknow 226003Uttar PradeshIndia Medical Consultant National Disease Control ProgramNational Health MissionLucknow 226003Uttar PradeshIndia Department of Hepatology Sanjay Gandhi Postgraduate Institute of Medical SciencesLucknow 226014Uttar PradeshIndia

bACKGROUND birth-dose(Hep-bD)followed by three additional doses(Hep-b3)of hepatitis b virus(HbV)vaccine are key to eliminating HbV by ***,Hep-bD and Hep-b3 coverage in our country is *** To studied the parent’s knowledge and awareness about HbV infection,its prevention,consequences and *** parents of 6 months to 8 years old children were interviewed to assess their knowledge&awareness about hepatitis b,its transmission,prevention,illness caused by this,and *** close-ended questions were admini-stered,and responses were recorded as‘yes’,‘no’,or‘not sure’.HbV knowledge score was calculated based on the sum of correct *** correct response scored one point and incorrect,missing or‘not sure’responses received no *** data are presented as number(%)and numerical data are expressed as *** were compared using Chi2 tests and level of significance was kept as pparents(58.3%mothers)of 384 children(89.9%ageppropriately vaccinated)were *** hundred and twenty-two(83.9%)children were Hep-b3 vaccinated.94.3%,87.5%,and 29.2%parents knew about polio,tetanus,and hepatitis b ***,41.2%,15.8%,and 23%parents knew about hepatitis b transmission,consequences of infection,and prevention *** 7.6%parents knew about three-dose schedule of hepatitis b *** 23%parents believed that vaccine could prevent HbV,15.7%knew that HbV affects *** of Hep-b3 vaccinated children were significantly more aware about HbV than the parents of unvaccinated children(pparents about hepatitis b is *** Increasing knowledge/awareness about HbV among parents may improve Hep-b3 vaccination coverage.

关键词： Hepatitis b Viral hepatitis Cirrhosis Hepatocellular carcinoma Hepatotropic viruses Transfusion transmitted infection Mother to child transmission

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Evolution of the paleogene succession of the western Himalayan foreland basin

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Geoscience Frontiers 2013年第2期4卷 199-212页

作者： b.p.singh CAS in Geology.banaras Hindu University

The paleogene succession of the Himalayan foreland basin is immensely important as it preserves evidence of India-Asia collision and related records of the Himalayan *** this paper,the depositional regime of the paleogene succession of the Himalayan foreland basin and variations in composition of the hinterland at different stages of the basin developments are *** paleogene succession of the western Himalayan foreland basin developed in two stages,*** stage and post-collisional *** the onset,chert breccia containing fragments derived from the hanging walls of faults and reworked bauxite developed as a result of erosion of the forebulge. The overlying early Eocene succession possibly deposited in a coastal system,where carbonates represent barriers and shales represent ***-section,the middle Eocene marl beds likely deposited on a tidal *** late Eocene/Oligocene basal Murree beds,containing tidal bundles,indicate that a mixed or semi-diurnal tidal system deposited the sediments and the sedimentation took place in a tidedominated *** the higher-up,the succession likely deposited in a river-dominated estuary or in meandering *** the beginning of the basin evolution,the sediments were derived from the precambrian basement or from the metasediments/volcanic rocks possessing terrains of the *** early and middle Eocene（54.7-41.3 Ma） succession of the embryonic foreland possibly developed from the sediments derived from the Trans-Himalayan schists and phyllites and Indus ophiolite of the north during syn-collisional *** detrital minerals especially the lithic fragments and the heavy minerals suggest the provenance for the late Eocene/Oligocene sequences to be from the recycled orogenic belt of the Higher Himalaya,Tethyan Himalaya and the Indus-suture zone from the north during post-collisional *** is also supported by the paleocurrent measurements those suggest main flows directed towards sou

关键词： Facies architecture provenance basin evolution paleogene Himalayan foreland Tectonics

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Global geoepidemiology of gastrointestinal surgery rates in Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1835-1844页

作者： Simcha Weissman Muhammad Aziz Ayrton bangolo Vignesh K Nagesh Htat Aung Midhun Mathew Lino Garcia Shiva A Chandar praveena Karamthoti Harinder bawa Aseel Alshimari Yabets Kejela Nazish Mehdi Chrishanti A Joseph Athri Kodali Rohan Kumar priya Goyal Sanya Satheesha Fnu Nivedita Nicole Tesoro Tanni Sethi Gurpreet singh Areej belal Alina Intisar Hirra Khalid Samuel Cornwell Suchith b Suresh Kareem Ahmed Karabo K Marole Om p Anand Rahat b Reshi Tej I Mehta Sameh Elias Joseph D Feuerstein Department of Medicine Hackensack Meridian Health Palisades Medical CenterNorth BergenNJ 07047United States Division of Gastroenterology and Hepatology University of Toledo Medical CenterToledoOH 43614United States Department of Medicine University of WashingtonSeattleWA 98195United States Department of Radiology Johns Hopkins University HospitalBaltimoreMD 21218United States Division of Gastroenterology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215United States

bACKGROUND Data regarding the worldwide gastrointestinal surgery rates in patients with Crohn’s disease(CD)remains *** To systematically review the global variation in the rates of surgery in *** A comprehensive search analysis was performed using multiple electronic databases from inception through July 1,2020,to identify all full text,randomized controlled trials and cohort studies pertaining to gastrointestinal surgery rates in adult patients with *** included continent based demographic data,CD surgery rates over time,as well as the geoepidemiologic variation in CD surgery *** analyses were conducted using *** Twenty-three studies spanning four continents were *** median proportion of persons with CD who underwent gastrointestinal surgery in studies from North America,Europe,Asia,and Oceania were 30%(range:1.7%-62.0%),40%(range:0.6%-74.0%),17%(range:16.0%-43.0%),and 38%*** clear association was found regarding the proportion of patients undergoing gastrointestinal surgery over time in North America(R^(2)=0.035)and Europe(R^(2)=0.100).A moderate,negative association was seen regarding the proportion of patients undergoing gastrointestinal surgery over time(R^(2)=0.520)in *** There appears to be significant inter-continental variation regarding surgery rates in *** evidencebased guidelines accounting for the geographic differences in managing patients with CD is ***,as a paucity of data on surgery rates in CD exists outside the North American and European continents,future studies,particularly in less studied locales,are warranted.

关键词： Gastrointestinal surgery Crohn’s disease Geoepidemiology Inflammatory bowel disease prevalence

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