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Research in Astronomy and Astrophysics 2014年第11期14卷 1491-1503页

作者： Mradul sharma Jitadeepa Nayak Maharaj krishna Koul Smarajit Bose Abhas Mitra Astrophysical Sciences Division Bhabha Atomic Research Centre The Bayesian and Interdisciplinary Research Unit Indian Statistical Institute

A detailed case study of γ-hadron segregation for a ground based atmo- spheric Cherenkov telescope is presented. We have evaluated and compared various supervised machine learning methods such as the Random Forest method, Artificial Neural Network, Linear Discriminant method, Naive Bayes Classifiers, Support Vector Machines as well as the conventional dynamic supercut method by simulating triggering events with the Monte Carlo method and applied the results to a Cherenkov telescope. It is demonstrated that the Random Forest method is the most sensitive machine learning method for γ-hadron segregation.

关键词： methods statistical -- telescopes

Numerical investigations on HCCI engine with increased induction induced swirl and engine speed

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Journal of Central South University 2015年第10期22卷 3837-3848页

作者： T.Karthikeya sharma G.Amba prasad Rao K.Madhu Murthy Department of Mechanical Engineering NIT

Homogeneous charge compression ignition(HCCI) mode of combustion is popularly known for achieving simultaneous reduction of NOx as well as soot emissions as it combines the compression ignition(CI) and spark ignition(SI) engine features. In this work, a CI engine was simulated to work in HCCI mode and was analyzed to study the effect of induction induced swirl under varying speeds using three-zone extended coherent flame combustion model(ECFM-3Z, compression ignition) of STAR-CD. The analysis was done considering speed ranging from 800 to 1600 r/min and swirl ratios from 1 to 4. The present study reveals that ECFM-3Z model has well predicted the performance and emissions of CI engine in HCCI mode. The simulation predicts reduced in-cylinder pressures, temperatures, wall heat transfer losses, and piston work with increase in swirl ratio irrespective of engine speed. Also, simultaneous reduction in CO2 and NOx emissions is realized with higher engine speeds and swirl ratios. Low speeds and swirl ratios are favorable for low CO2 emissions. It is observed that increase in engine speed causes a marginal reduction in in-cylinder pressures and temperatures. Also, higher turbulent energy and velocity magnitude levels are obtained with increase in swirl ratio, indicating efficient combustion necessitating no modifications in combustion chamber design. The investigations reveal a total decrease of 38.68% in CO2 emissions and 12.93% in NOx emissions when the engine speed increases from 800 to 1600 r/min at swirl ratio of 4. Also an increase of 14.16% in net work done is obtained with engine speed increasing from 800 to 1600 r/min at swirl ratio of 1. The simulation indicates that there is a tradeoff observed between the emissions and piston work. It is finally concluded that the HCCI combustion can be regarded as low temperature combustion as there is significant decrease in in-cylinder temperatures and pressures at higher speeds and higher swirl ratios.

关键词： HCCI engine ECFM-3Z swirl ratio emissions and performance

Review on current concepts of myopia and its control strategies

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International Journal of Ophthalmology(English edition) 2021年第4期14卷 606-615页

作者： Raju Kaiti Ranjila Shyangbo Indra prasad sharma Manish Dahal Nepal Eye Hospital Kathmandu 44600Nepal National Academy of Medical Sciences Kathmandu 44600Nepal Gyalyum Kesang Choeden Wangchuck National Eye Center JDW National Referral HospitalThimpu 11001Bhutan

Myopia poses a significant burden on the healthcare system,economy and quality of *** is an emerging global public health challenge and requires interventions to delay or stop onset and *** changing times and evidence,the concepts of myopia are changing along with the treatment and control *** modifications including increased outdoors time and reduced near work,optical and pharmaceutical management options are *** paper presents a current overview on the concepts of myopia,and is expected to summarize updates on myopia control methods.

关键词： atropine myopia myopia control myopic maculopathy public health

Control of peak pressures of an HCCI engine under varying swirl and operating parameters

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Frontiers in Energy 2016年第3期10卷 337-346页

作者： T. KARTHIKEYA sharma G. AMBA prasad RAO K. MADHU MURTHY Department of Mechanical Engineering NIT Warangal Warangal506004 India

The major advantages of homogeneous charge compression ignition （HCCI） are high efficiency in combination with low NOx-emissions. However, one of the major challenges with HCCI is the control of higher peak pressures which may damage the engine, limiting the HCCI engine life period. In this paper, an attempt is made to analyze computationally the effect of induction swirl in controlling the peak pressures of an HCCI engine under various operating parameters. A single cylinder 1.6 L reentrant piston bowl diesel engine is chosen. For computational analysis, the ECFM-3Z model of STAR - CD is considered because it is suitable for analyzing the combustion processes in SI and CI engines. As an HCCI engine is a hybrid version of SI and CI engines, the ECFM- 3Z model with necessary modifications is used to analyze the peak pressures inside the combustion chamber. The ECFM-3Z model for HCCI mode of combustion is validated with the existing literature to make sure that the results obtained are accurate. Numerical experiments are performed to study the effect of varying properties like speed of the engine, piston bowl geometry, exhaust gas recirculation （EGR） and equivalence ratio under different swirl ratios in controlling the peak pressures inside the combustion chamber. The results show that the swirl ratio has a considerable impact on controlling the peak pressures of HCCI engine. A reduction in peak pressures are observed with a swirl ratio of 4 because of reduced in cylinder temperatures. The combined effect of four operating parameters, i.e., the speed of the engine, piston bowl geometry, EGR, and equivalence ratio with swirl ratios suggest that lower intake temperatures, reentrant piston bowl, higher engine speeds and higher swirl ratios are favorable in controlling the peak pressures.

关键词： HCCI engine ECFM-3Z Swirl ratio peak pressures engine speed piston bowl geometry

Half-a-century(1971–2020)of glacier shrinkage and climatic variability in the Bhaga basin,western Himalaya

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Journal of Mountain Science 2023年第3期20卷 299-324页

作者： DAS Suresh sharma Milap Chand MURARI Madhav krishna NÜSSER Marcus SCHMIDT Susanne Centre for the Study of Regional Development Jawaharlal Nehru UniversityNew Delhi 110067India National Geochronology Facility Inter-University Accelerator CentreNew Delhi 110067India Department of Geography South Asia Institute(SAI)Heidelberg UniversityHeidelberg 69115Germany Heidelberg Centre for the Environment(HCE) Heidelberg UniversityHeidelberg 69120Germany

Glacier shrinkage is a globally occurring ***-resolution change detection based on frequent mapping and monitoring of high-altitude glaciers is necessary to precisely evaluate future water availability and to understand glacier evolution under different climatic scenarios in the Hindukush-Karakoram-Himalayan(HKH)*** also holds true for the Bhaga basin of the western *** study investigates glacier and glacier lake changes in the Bhaga basin,over the last five decades based on satellite imagery including Corona KH4(1971),Landsat 7 Enhanced Thematic Mapper Plus(ETM+;2000),Linear Imaging Self-Scanning Sensor(LISS Ⅳ;2013),and Sentinel 2(2020).Regional temperature and precipitation trends were evaluated from gridded climatic datasets(1900–2020).In the Bhaga basin 306 glaciers(>0.2 km^(2))were mapped with a total area of 360.3±4.0 km^(2),of which 55.7±0.6 km^(2)was covered with debris in *** total glacier covered area decreased by∼8.2±1.5%(0.16±0.03%yr-1)during the entire observation period 1971–2020,with noticeable heterogeneity between tributary *** the past two decades(2000–2020),the deglaciation rate has increased significantly(0.25%yr-1)compared to the previous decades(1971–2000;0.12%yr-1).Glacier lake area increased by 0.6±0.1 km^(2)(0.012 km^(2)yr-1)between 1971 and *** NCEP/NCAR climatic data reveals an increase of 0.63℃in temperature and a decrease of 6.39 mm in precipitation for the period 1948–*** comparison,APHRODITE data shows an increasing trend in temperature of 1.14℃between 1961 and 2015 and decreasing trend in precipitation of 31 mm between 1951 and *** NCEP/NCAR and APHRODITE data reveal significant temperature increase and precipitation decrease since the 1990s,which have probably augmented ice loss in the Bhaga basin during the early 21st century.

关键词： Glacier change Remote sensing APHRODITE NCEP/NCAR reanalysis Climate change Western Himalaya

MicroRNAs:a new ray of hope for diabetes mellitus

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Protein & Cell 2012年第10期3卷 726-738页

作者： Munish Kumar Sayantan Nath Himanshu K prasad G D sharma Yong Li Department of Biotechnology Assam UniversitySilchar 788011 India 2 Department of Life Science and Bioinformatics Assam UniversitySilchar 788011 India 3 Department of Biochemistry and Molecular Biology University of LouisvilleKY 40292USA

Diabetes mellitus has become one of the most common chronic diseases,thereby posing a major challenge to global *** by high levels of blood glucose(hyperglycemia),diabetes usually results from a loss of insulin-producing β-cells in the pancreas,leading to a deficiency of insulin(type 1 diabetes),or loss of insulin sensitivity(type 2 diabetes).Both types of diabetes have serious secondary complications,such as microvascular abnormalities,cardiovascular dysfunction,and kidney *** complex factors,such as genetic and environmental factors,are associated with the pathophysiology of *** the past two decades,the role of small,single-stranded noncoding microRNAs in various metabolic disorders,especially diabetes mellitus and its complications,has gained widespread attention in the scientific *** first as an endogenous regulator of development in the nematode Caenorhabditis elegans,these small RNAs post-transcriptionally suppress mRNA target *** this review,we discuss the potential roles of different microRNAs in diabetes and diabetes-related complications.

关键词： diabetes diabetic complications dicer glucose insulin microRNA pancreas

Current trends of antibiotic resistance in clinical isolates of Staphylococcus aureus

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Frontiers in Biology 2014年第4期9卷 287-290页

作者： Kapil Dev sharma Rajendra prasad SAINI Loganathan KARTHIK Dhanwantri Hospital and Research Centre Jaipur Rajasthan India Department ofBiosciences Shri Jagdishprasad Jhabarmal Tibrewala University Jhunjhunu Rajasthan 333 001 India

Staphyloccus aureus （S. aureus） is a well known human pathogen known to causes a verity of infections in humans. In recent years S. aureus is reported to show drug resistant toward commonly known drugs. Therefore, this study was designed to study the pattern of antibiotic resistance in 50 clinical isolates ofS. aureus isolated at Dhanwantri Hospital and Research Centre, Jaipur, Rajasthan, India. S. aureus cultures were isolated from different clinical samples, pus, throat swabs and urine on Blood agar and MacConkey agar and Chrom agar plats and characterized by an array of microscopic and biochemical tests. Antibiotic sensitivity test was performed by standard disc diffusion method （Kirby bayer＇s method） on Muller Hinton agar plates. During this study, among 50 S. aureus isolates 48 （96%） were found to be resistance toward Aztreonam and Doxicycline followed by Ciprofloxacin （n = 45, 90%）, Cefpodoxime and Ceftazidime （n = 44, 88%）, Cefuroxime （n = 40, 80%）, Pipracillin ＋ Tazobactum （n = 38, 76%）, Cefoparazone （n = 36, 72%）, Amoxicillin ＋ Clavulanic acid and Ceftriaxone （n = 33, 66%）, Levofloxacin （n = 32, 64%）, Moxifloxacin （n = 31, 62%）, Ofloaxacin （n = 25, 50%）, Cloxacillin （n = 22, 44%）, Azithromycin （n = 21, 42%）, Clindamycin （n = 19, 38%）, Meropenem （n = 18, 36%）, Clarithromycin （n = 16, 32%）, Ampicillin ＋ sulbactam （n = 13, 26%）, Amikacin （n = 12, 24%）, Impipenem （n = 8, 16%）, Linezolid and Methicillin （n = 7, 14%） and Teicoplanin （n = 3, 6%）. In conclusion, the isolated S. aureus found to be resistant toward common antibiotics, however all isolates were found to be susceptible to Vancomycin.

关键词： Staphyloccus aureus infections antibiotic resistance

Ecological Consequences of Land Use Change: Forest Structure and Regeneration across the Forest-grassland Ecotone in Mountain Pastures in Nepal

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Journal of Mountain Science 2014年第4期11卷 838-849页

作者： Lila Nath sharma Ole Reidar VETAAS Ram prasad CHAUDHARY Inger Elisabeth MREN Department of Geography University of Bergen Bergen 5020 Norway Research Centre for Applied Science and Technology and Central Department of Botany Tribhuvan UniversityKathmandu 977 Nepal

The ecotone, the spatial transition zone between two vegetation communities, is claimed to have more species than the adjoining communities. However, empirical studies do not always confirm higher richness at the ecotone. The ecotone position and structure are dynamic over time and space and it is driven by the changes in climate, land use or their interaction. In this context, we assessed the forest- grassland ecotone of temperate mountains in central Nepal by i） comparing species composition and richness across the ecotone, ii） analyzing if the forestgrassland ecotone is shifting towards the grassland center by colonizing them with trees, and iii） discussing the consequence of changed disturbance regime in the dynamics of this ecotone and the surrounding grasslands. We analyzed vegetation data sampled from belt transects laid across the forest- grassland ecotone in semi-natural grassland patches. Vegetation data consisting of species richness and composition, and size structure and regeneration of the two most dominant tree species, namely Rhododendron arboreum and Abies spectabilis, from the transects, were used to analyze the trend of the forest-grassland ecotone. Forest and grasslands were different in terms of floristic composition and diversity. Vascular plant speciesrichness linearly increased while moving from forest interior to grassland center. Spatial pattern of tree size structure and regeneration infers that forest boundary is advancing towards the grasslands at the expense of the grassland area, and tree establishment in the grasslands is part of a suceessional process. Temporally, tree establishment in grasslands started following the gradual decline in disturbance. We argue that local processes in terms of changed land use may best explain the phenomenon of ecotone shift and consequent forest expansion in these grasslands. We underpin the need for further research on the mechanism, rate and spatial extent of ecotone shift by using advaneed tools to

关键词： Ecotone shift Grasslands Forest Landuse change Rhododendron

Surveying the genomic landscape of silage-quality traits in maize(Zea mays L.)

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The Crop Journal 2023年第6期11卷 1893-1901页

作者： Jatin sharma Shubham sharma krishna Sai Karnatam Om Prakash Raigar Chayanika Lahkar Dinesh Kumar Saini Sushil Kumar Alla Singh Abhijit Kumar Das Priti sharma Ramesh Kumar Department of Plant Breeding and Genetics Punjab Agricultural UniversityLudhianaPunjab 141004India School of Agricultural Biotechnology Punjab Agricultural UniversityLudhianaPunjab 141004India ICAR-Indian Institute of Maize Research LudhianaPunjab 141004India Department of Plant and Soil Science Texas Tech UniversityLubbockTX 79409-2122USA

Despite the longstanding importance of silage as a critical feed source for ruminants,its quality improvement has been largely *** numerous quantitative trait loci(QTL)and genes affecting silage quality in maize have been reported,only a few have been effectively incorporated into breeding *** this gap,the present study undertook a comprehensive meta-QTL(MQTL)analysis involving 523 QTL associated with silage-quality traits collected from 14 published *** the 523 QTL,405 were projected onto a consensus map comprising 62,424 genetic markers,resulting in the identification of 60 MQTL and eight *** average confidence interval(CI)of the MQTL was 3.9-fold smaller than that of the source *** of the 60 identified MQTL were classified as breeder’s MQTL owing to their small CIs,involvement of more QTL,and large contribution to phenotypic ***-third of the MQTL co-localized with DNA marker-trait associations identified in previous genomewide association mapping studies.A set of 78 high-confidence candidate genes influencing silage quality were identified in the MQTL *** genes and associated markers may advance marker-assisted breeding for maize silage quality.

关键词： Meta-QTL Silage quality Maize GWAS Candidate genes

A Comparative Study on the Corrosion Behaviour of Hard Anodic Coatings on AA 6061 Obtained Using DC and Pulsed DC Power Sources

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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 647-656页

作者： Franco M. Hari krishna T. Anju M.Pillai A.Rajendra A.K.sharma Thermal Systems Group ISRO Satellite Centre

The corrosion behaviour of the hard anodic coatings prepared by three different methods viz., conventional hard anodizing （C-HA）, pulse hard anodizing （P-HA） and low voltage room temperature pulse hard anodizing （LVP- HA） on AA 6061 was compared using electrochemical impedance spectroscopy （EIS） and linear polarisation. Scanning electron microscope （SEM） was used to study the surface morphology before and after corrosion. EIS data revealed that no significant difference in corrosion resistance was observed among three types. Rp, Icorr and Ecorr were found to be highly stable over the exposure period up to 72 h which confirms the excellent corrosion resistance. The studies indicate that the corrosion resistance of LVP-HA and P-HA, which are processed at lower voltage and at relatively higher temperatures, are comparable to that of C-HA which is processed at sub-zero temperatures and high operating voltages. The corrosion resistance of all coatings was found to be improved after hydrothermal sealing.

关键词： Aluminium Anodic films EIS Polarisation SEM