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Reproductive biology of Cornus capitata Wall. ex Roxb.: a native species in East Asia

Journal of Forestry Research 2019年第6期30卷 2039-2050页

作者： Vinod prasad Khanduri Arun Sukumaran Chandra Mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and Forestry

The reproductive biology of Cornus capitata was studied in detail from June 2014 to October 2015 in Tehri Garhwal, Uttarakhand, western Himalaya, India and elucidated floral morphology, confirming autogamy, geitonogamy, and xenogamy. A new inflorescence ball formed each year with developing fruits that were initiated the previous year; thus reproduction is a continuous cycle. The total pollen production within a tree ranged between 4.0 × 10~7 and 9.3 × 10~7. Anthesis peaked between 08:00 and 10:00. There was significant effect of micro-environmental condition on anthesis(F = 243.8, p = 3.01). A significant positive relationship between the number of lateral shoots and total inflorescence showed that the inflorescence production in C. capitate depends largely on the number of lateral shoots. Time and concentration of various solutions significantly affected pollen germination(time: F = 5.39, p = 0.002; concentration: F = 1.40,p = 0.234). Anthophora bees and thrips were observed as the main pollinators. There was a significant difference in seed set between natural and obligate self-pollination(t = 11.84, p = 1.99). Significant effect was also observed on fruit size(t = 8.88, p = 2.09) between open and shaded conditions. SEM micrographs of pollen grains showed that the shape of dehydrated pollen grains differed greatly due to variations in the rate of dehydration among pollen grains within the anther. Seed germination was observed only in quality seed derived from open pollination, supporting xenogamy in C. capitata. Findings of the present study will be of immense value in formulating effective conservation measures for the species in wild habitats.

关键词： Floral development Pollen production Pollination Pollinators Reproductive success SEM analysis

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Pollinator-mediated self-pollination and reproductive assurance in an isolated tree of Magnolia grandiflora L.

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Ecological Processes 2020年第1期9卷 517-525页

作者： Arun Sukumaran Vinod prasad Khanduri Chandra Mohan sharma College of Forestry VCSG Uttarakhand University of Horticulture and ForestryRanichauriTehri GarhwalUttarakhand 249199India

Background:The ability to produce seeds when pollinators or potential mates are scarce is one of the principal advantages of self-pollination in flowering ***,the role of pollinators mediating self-pollination to ensure seed set when pollen or potential mates are limited has received less *** study examined the reproductive consequences and involvement of pollinators in assuring seed set in an isolated tree of Magnolia grandiflora,a predominantly outcrossing ***:We tested various aspects of reproduction such as flower density,floral rewards,stigma receptivity,pollinator abundance and behaviour,fruit set and seed set,in two successive reproductive years(2015-2016).Results:Flowers of *** possess a suite of traits facilitating pollinator-mediated self-pollination(PMS),although the chances of autonomous self-pollination are reduced due to herkogamy,spatial separation of anther and *** mean pollen production/flower was 5,152,289±285,094 with a pollen-to-ovule ratio of 39430±*** found a significant positive correlation between number of visits and seed production for bees(r=0.5099,p=0.0007)and beetles(r=0.7159,p=0.00001),indicating these are effective at *** was a significant negative correlation for thrips(r=-0.3206,p=0.044)and no correlation for flies or *** percent fruit set was 100%and the seed set per ovule ranged between 19 and 20%.Conclusions:PMS will guarantee reproductive assurance and mitigate the effect of reduced mates or pollen limitation which is expected to increase the fecundity and establishment of individual trees in geographically isolated locations.

关键词： Pollinator-mediated self-pollination Magnolia grandiflora Autonomous self-pollination Pollinator behaviour Reproductive assurance

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Does offering only the spherical contact lens trial to the low astigmats mislead the practitioners?

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International Journal of Ophthalmology(English edition) 2021年第8期14卷 1281-1284页

作者： Monica Chaudhry Surendra prasad Sah Indra prasad sharma Soujanya Mondal Department of Optometry and Vision Science Amity UniversityHaryana 122003India School of Health Sciences Ansal UniversityGurugramHaryana 122003India Himalaya Eye Hospital GharinpatanPokhara 00977Nepal Gyalyum Kesang Choeden Wangchuck National Eye Center JDW National Referral HospitalThimphu 11001Bhutan Optsight Eye Care HCB RoadAmulapattiNear MFCSivasagarAssam 785640India

AIM:To compare the visual acuity(VA),comfort,and patient preference in a soft toric contact lens(TCL)versus soft spherical contact lens(SCL)in low astigmatic subjects during the contact lens(CL)***:This subject-masked,block randomized,2×2 crossover study recruited 40 neophyte subjects(80 eyes)aged 18 to 33 y with astigmatism in the range of 0.75-1.25 D with or without spherical power from-6.00 D to+6.00 *** participants were scheduled for two days CL trial and were fitted with the best-fit SCL and *** 4 h of wear,they were assessed objectively for high contrast VA and subjective vision,comfort,and ***:The responses of 36 subjects(response rate 90%)with a mean age of 23.02±2.97 y(range 18 to 33 y)were ***-line improvement of monocular VA in the logMAR chart was reported to TCL as compared to SCL(-0.044±0.06 vs 0.04±0.03 logMAR,P=0.01)but the binocular vision remained similar(-0.12±0.07 vs-0.14±0.04 logMAR,P=0.38).Subjects felt a noticeable difference in clarity when shifted to TCL as compared to the *** satisfaction with vision(vision quality)was significantly better with TCL(P=0.03).The fatigue with TCL was graded less at 2.5±0.6,compared to SCL at 4.6±1.3(P=0.04).Thirty-three participants(91.6%)preferred to use contact lens of which 26 participants(79%)preferred ***:The findings suggest that VA and comfort are better with TCL as compared to SCL which is only observed if the patient was offered both offering SCL with spherical equivalent power alone as the first option can mislead the practitioner;TCL trial should be the first choice of the lens in low-to-moderate astigmatism.

关键词： astigmatism comfort spherical contact lens toric contact lens visual acuity

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Design and Analysis of Cascaded Hybrid-Bridge Multi-Cell Multilevel Inverter with Reduced Total Harmonic Distortion Profile

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Energy Engineering 2022年第6期119卷 2585-2605页

作者： Bulbul sharma N.Karthick Durgesh prasad Bagarty Lovely Professional University Jalandhar144402India College of Engineering and Technology Bhubaneswar751003India

This multilevel inverter methodology is the center of focus among researchers in recent *** has been focused due to its advantages over existing topologies,drawbacks and improvement of power quality,Multi-level inverter has the ability to generate nearly sinusoidal *** sinusoidal wave can be further improved by increasing the level of output voltage or with the help of filter design,and this manuscript presents single-phase Multi cell Multi-Level Inverter(MLI).It has been considered for reducing component count to get a higher number of output voltage levels and lower Total harmonics distortion *** comprises with four symmetric DC input voltage and 10 IGBT switches to produces stepped output of 9 level,and when deploy asymmetric Dc voltage source the same circuit will produce 31 level output with some changes in firing scheme,moreover this circuit is the family of cascaded hybrid bridge inverter so this circuit covered advantage of CHB MLI,This circuit uses lower *** switch as compared to existing conventional MLIs such as FC-MLI,CHB-MLI,NPC-MLI,This paper also provides one of most pertinent controls and modulation mechanisms for a MLI using a hybrid reference/carrier-oriented sinusoidal PWM *** last,simulated outcomes are to validate the performance of both architectures in MLI structure as well as verify the concept.

关键词： Conventional topology multi-level inverters(MLIs) pulse width modulations(PWM) reduced component counts total of harmonics distortion(THD)

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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

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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

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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

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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

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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

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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

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