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美国大陆外来入侵物种斑马纹贻贝(Dreissena polymorpha)潜在生境预测模型 被引量:38
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作者 李明阳 居云为 +1 位作者 sunil kumar Thomas J.Stohlgren 《生态学报》 CAS CSCD 北大核心 2008年第9期4253-4258,共6页
防止外来生物入侵造成危害的重要手段是阻止可能造成入侵的物种进入适合其生存的地区。论文以1864个美国外来入侵物种斑马纹贻贝定点发生数据和开放式基础地理信息数据库Daymet的34个环境变量为主要信息源,采用逻辑斯蒂回归(LR)、分类... 防止外来生物入侵造成危害的重要手段是阻止可能造成入侵的物种进入适合其生存的地区。论文以1864个美国外来入侵物种斑马纹贻贝定点发生数据和开放式基础地理信息数据库Daymet的34个环境变量为主要信息源,采用逻辑斯蒂回归(LR)、分类与回归树模型(CART)、基于规则的遗传算法(GARP)、最大熵法(Maxent)4种途径,建立美国大陆部分潜在生境预测模型,从接受者运行特征曲线下面积(AUC)、Pearson相关系数、Kappa值3个方面来检验模型预测精度,在此基础上分析斑马纹贻贝的空间分布规律及其环境影响因素。研究结果表明:在3个评价指标中,4个生态位模型预测精度均达到优良水平,其中Maxent在物种现实生境模拟、主要生态环境因子筛选、环境因子对物种生境影响的定量描述方面都表现出了优越的性能;距水源距离、海拔高度、降水频率、太阳辐射是影响物种空间分布的主要环境因子。论文提出的研究方法对中国外来入侵物种生境预测具有较强的借鉴意义,研究结果对中国海洋外来入侵物种沙筛贝的预测与防治,具有一定的指导作用。 展开更多
关键词 外来入侵物种 斑马纹贻贝 潜在生境 生态位模型
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濒危野生动物潜在生境空间建模方法--以印度野牛(Bos gaurus)为例 被引量:14
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作者 李明阳 巨云为 +1 位作者 sunil kumar Thomas J. Stohlgren 《东北林业大学学报》 CAS CSCD 北大核心 2009年第5期88-91,共4页
以2002年印度野牛(Bos gaurus)印度次大陆的空间分布图和开放式生态环境数据库的30个环境变量为主要信息源,采用逻辑斯蒂回归(LR)、分类与回归树模型(CART)、基于规则的遗传算法(GARP)、最大熵法(Maxent)4种生态位模型,进行印度野牛印... 以2002年印度野牛(Bos gaurus)印度次大陆的空间分布图和开放式生态环境数据库的30个环境变量为主要信息源,采用逻辑斯蒂回归(LR)、分类与回归树模型(CART)、基于规则的遗传算法(GARP)、最大熵法(Maxent)4种生态位模型,进行印度野牛印度大陆部分潜在生境预测。结果表明:4个预测模型总体性能相差不大,其中,Maxent模型单项指标、总体平均值均最高;年平均降水量、温度季节性变化、林木覆盖率、标准归一化植被指数、海拔高度、距主要道路距离是影响印度野牛空间分布的主要环境因子;增加林木覆盖率、减少道路修建引起的生境破碎化、保证水源是印度野牛保护的主要措施。 展开更多
关键词 濒危物种 印度野牛 潜在生境 生态位模型
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Introduction to the Special Issue on Mathematical Aspects of Computational Biology and Bioinformatics-Ⅱ
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作者 Dumitru Baleanu Carla M.A.Pinto sunil kumar 《Computer Modeling in Engineering & Sciences》 2025年第5期1297-1299,共3页
1 Summary Mathematical modeling has become a cornerstone in understanding the complex dynamics of infectious diseases and chronic health conditions.With the advent of more refined computational techniques,researchers ... 1 Summary Mathematical modeling has become a cornerstone in understanding the complex dynamics of infectious diseases and chronic health conditions.With the advent of more refined computational techniques,researchers are now able to incorporate intricate features such as delays,stochastic effects,fractional dynamics,variable-order systems,and uncertainty into epidemic models.These advancements not only improve predictive accuracy but also enable deeper insights into disease transmission,control,and policy-making.Tashfeen et al. 展开更多
关键词 computational techniquesresearchers effectsfractional dynamicsvariable order understanding complex dynamics infectious diseases chronic health conditionswith computational techniques mathematical modeling infectious diseases chronic health conditions DELAYS
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Ecological Assessment of Nano Micronutrient Composites on Growth Dynamics and Yield Performance of Late-Sown Wheat(Triticum aestivum L.)
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作者 Samyak Jain Vivek kumar Pathak +16 位作者 Anant Deogaonkar Piyush Vashistha Deepshree kumar Gumpi Kabak kumar Gaurav Saurabh Gangola Divya Pragati Srivastava sunil kumar Anupama Rawat Pallavi Bhatt Rowndel Khwairakpam Supriya Gupta Somya Misra Ashish Gaur Samiksha Joshi Rajneesh Bhardwaj 《Research in Ecology》 2025年第4期97-107,共11页
Background:The study examines the ecological impact of nano-micronutrient composites on the growth and maturation of late-planted wheat within an agroecological framework.Methods:Experiments conducted using a Randomiz... Background:The study examines the ecological impact of nano-micronutrient composites on the growth and maturation of late-planted wheat within an agroecological framework.Methods:Experiments conducted using a Randomized Block Design(RBD)with three replications and eight treatment combinations,ensured uniform plant populations prior to treatment applications.Significant variations were observed across multiple growth parameters,including tiller density per square meter and dry matter accumulation at 30,60,90,and 120 days after sowing(DAS).Results:Notably,the treatment involving RDF+20 ppm rGO-Fe+rGO-Zn with two foliar sprays at 45 and 60 DAS(T6)exhibited markedly superior growth performance compared to the control and conventional zinc and iron applications.Maximum grain yield(29.2 q/ha)was achieved in T8(RDF+20ppm rGO-Fe+rGO-Zn with two sprays at 45 and 60 DAS)whereas straw yield(50.5 q/ha),biological yield(77.1 q/ha),Harvest Index(38.7%)and Grain Straw ratio(0.6)were found maximum in RDF+20ppm rGO-Fe+rGO(Reduced Graphene oxide)−Zn with two sprays at 45 and 60 DAS(T6).Conclusion:The application of reduced graphene oxide(rGO)-based iron and zinc nanoparticles significantly improved nutrient uptake and utilization efficiency,leading to enhanced crop vigor and yield.The study underscores the ecological importance of integrating nanotechnology with nutrient management to sustain a healthy and balanced agroecosystem.This research focuses on sustainable agriculture,nanofertilizers,nutrient use efficiency,and ecological impact,which follows the Q16,Q57,and O13 JEL(Journal of Economic Literature)classification. 展开更多
关键词 Ecology Sustainability Nano fertiliser rGO-Zn rGO-Fe MICRONUTRIENTS WHEAT
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Ecological Implications of Foliar Zinc and Iron Application on Growth Dynamics and Sustainable Productivity of Chickpea(Cicer arietinum L.)
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作者 Priyanka Bohra kumar Gaurav +13 位作者 Deepak Kholiya Piyush Vashistha Anant Deogaonkar Rajesh Vaidya Gumpi Kabak Divya Saurabh Gangola sunil kumar Anupama Rawat Shashank Srivastav Vivek kumar Pathak Pragati Srivastava Amit Mittal Ashish Gaur 《Research in Ecology》 2025年第4期85-96,共12页
The physico-chemical analysis of agricultural soil revealed a textured sandy loam at the surface(0–15 cm),with low organic carbon content(0.42%)and moderate levels of nitrogen(157 kg/ha),phosphorus(15.5 kg/ha),and po... The physico-chemical analysis of agricultural soil revealed a textured sandy loam at the surface(0–15 cm),with low organic carbon content(0.42%)and moderate levels of nitrogen(157 kg/ha),phosphorus(15.5 kg/ha),and potassium(112.6 kg/ha),under neutral pH conditions(pH 7.4).The chickpea variety PG-186 was used to evaluate the impact of nutrient treatments on plant performance and agroecological outcomes.Experimental findings demonstrated a significant influence of various treatments on the growth,yield,and economic returns of chickpea cultivation.The treatment comprising 100%Recommended Dose of Fertilizers(RDF)along with foliar application of 0.6%ZnSO_(4) and 0.9%FeSO_(4) at pre-flowering and pod development stages(T8)resulted in the maximum plant height(15.5 cm,33.7 cm,45.0 cm),dry matter accumulation(27.5 g,245.2 g,1006.7 g/m^(2)),and number of branches per plant(3.47,5.00,and 8.63)at 45,75,and 105 Days After Sowing(DAS),respectively.This treatment also resulted in the highest grain yield(21.00 q/ha)and stover yield(38.67 q/ha),along with a maximum net return of₹95,392/ha and a benefit-to-cost ratio of 2.32.From an ecological standpoint,this study highlights the vital role of balanced and targeted nutrient management in enhancing agroecosystem productivity while maintaining ecological balance.The integration of micronutrient foliar sprays not only boosts nutrient uptake efficiency and plant health but also reduces dependency on excessive chemical fertilizers,thereby mitigating potential negative impacts on soil ecology.Overall,the findings underscore the ecological importance of optimizing nutrient inputs in legume-based cropping systems to foster sustainable agricultural practices that align with ecological resilience,soil health preservation,and environmental stewardship. 展开更多
关键词 CHICKPEA Foliar Application ZnSO4 FESO4 Growth PRODUCTIVITY
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Influence of Processed Mustard Seed Meals on Growth and Health Parameters in Indian Major Carps
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作者 Shivanshu Garg Himanshu Punetha +8 位作者 Anant Deogaonkar Deepshree kumar Ashutosh Mishra Ashokkumar Verma Nityanand Pandey Ranjeet Singh Saurabh Gangola sunil kumar Amit Mittal 《Research in Ecology》 2025年第2期93-105,共13页
The current investigation focuses on intertwined relationships of ecology and aquaculture for the benefit of farmers involved in fish farming practices.The study evaluated glucosinolate reduction in black,brown,and wh... The current investigation focuses on intertwined relationships of ecology and aquaculture for the benefit of farmers involved in fish farming practices.The study evaluated glucosinolate reduction in black,brown,and white mustard meals as fish feed ingredients for Indian Major Carps.Fish were fed with 10%mustard meal-supplemented diets in three forms:Raw(R),Anti-nutritional Rich(AR),and Anti-nutritional Lowered(AL),alongside a control group using floating feed.The three-month indoor experiment(September-November 2023)was conducted in FRP tanks with triplicate treatments.Blood analysis revealed compromised health in AR-fed carps,with reduced hemoglobin levels in rohu,catla and mrigal and elevated total leukocyte counts indicating inflammation in all the three carps studied here.Liver function was impaired in AR-fed fish,shown by increased alanine transaminase levels,highest in rohu followed by mrigal and catla.Histopathological examination of AR-fed carps liver tissue revealed necrotic spots,deformed hepatocytes,and significant vacuolation.In contrast,AL-fed fish demonstrated improved health parameters through Complete Blood Count analysis,liver function tests,and histo-pathological observations,suggesting successful reduction of anti-nutritional factors in the processed mustard meals.In near future,replacement of unprocessed seed meal with processed seed meal will lead to economic gains in fish farming. 展开更多
关键词 Biochemical Parameters GLUCOSINOLATES Growth Parameters Histo-Pathological Analysis Indian Major Carps Liver Function Test
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Immunogenic proteins of Orientia tsutsugamushi and implications for scrub typhus intervention:A narrative review
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作者 Shakshi Shah Ankita Sharma +4 位作者 Alka Rana Rakesh kumar Amit kumar Sharma sunil kumar Dixit Sharma 《Asian Pacific Journal of Tropical Medicine》 2025年第4期149-155,共7页
Scrub typhus is an acute undifferentiated febrile infectious disease transmitted by a chigger(genus Leptotrombidium)bite carrying Orientia(O.)tsutsugamushi,affecting millions of people annually while more than one bil... Scrub typhus is an acute undifferentiated febrile infectious disease transmitted by a chigger(genus Leptotrombidium)bite carrying Orientia(O.)tsutsugamushi,affecting millions of people annually while more than one billion people are susceptible.Endemic areas are expanding to Africa,Europe,Middle East,and South America which is concerning,as despite best efforts,there is no vaccine to combat the bacteria.There are now three species of Orientia and over 20 strains of O.tsutsugamushi.The past attempts to develop a vaccine have been ineffective as they confer homologous strain-specific immunity.Various immunogenic proteins of O.tsutsugamushi have been identified that interact with the extracellular matrix(fibronectin)or vMLL5 receptor and modify the cytoskeleton of non-phagocytic host cells,which aids in host cell adhesion and invasion.These highly conserved proteins involve type specific antigen 56(TSA56),47 kDa,OmpA,and autotransporter proteins(ScaA,ScaB and ScaC).TSA56 is the most immunogenic and contains four types of hypervariable regions.Out of all autotransporter proteins,ScaA provides the homologous strains specific immunity and when coupled with TSA56 it shows better protective immunity against heterologous strains.The review provides detailed insight into the potential immunogenic proteins of Orientia which can be utilized to develop the vaccine.Furthermore,studies focused on highly antigenic proteins will provide more insight into their roles in developing therapeutics and easy-to-handle rapid diagnostic kits. 展开更多
关键词 Orientia tsutsugamushi Immunogenic genes Microbial pathogenesis VACCINE Scrub typhus
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Enhanced Electrochemical Performance and Theoretical Insights of Ni-Intercalated Ti_(3)C_(2)T_(x) MXene
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作者 Syed Muhammad Zain Mehdi Hafiz Ghulam Abbas +6 位作者 Muzahir Ali Syed Bilal Hasan Rizvi Sung Ryul Choi Jeung Choon Goak Yongho Seo sunil kumar Naesung Lee 《Energy & Environmental Materials》 2025年第3期172-181,共10页
Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs ... Two-dimensional MXenes are renowned for their remarkable electrical conductivity and electrochemical activity making them highly promising for electrode applications.However,the restacking of MXene nanosheets impairs their functionality by reducing active sites and obstructing ionic transport.This study presents a facile synthesis approach for nickel-intercalated MXene,designed to enhance surface reactivity,avoid restacking,and achieve improved electrochemical performance.Electrochemical studies revealed that the nickel-MXene hybrid showed better cycling stability,retaining 83.7%of its capacity after 10000 cycles and attaining an energy density of 26 Wh kg^(-1) at a power density of 1872Wkg^(-1).It also exhibited overpotentials of 109 and 482 mV at 10 and 100 mA cm^(-2),respectively,in the hydrogen evolution reaction.To predict the structural and electrical alterations caused by nickel inclusion,as well as to understand the intercalation mechanism,spin-polarized density functional theory calculations were carried out.The theoretical results showed an improved carrier concentration for nickel-MXene.Nickel-MXene possessed superior electronic characteristics and surplus active sites with hexagonal closed-packed(hcp)edge sites,which enhanced electrochemical properties.Our results demonstrate that nickel intercalation prevents the restacking of MXene but also significantly improves their electrochemical characteristics,making them ideal for energy storage and catalytic applications. 展开更多
关键词 DFT HER MXene Ni intercalation redox reaction
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Development and validation of a questionnaire to assess hypertension risk factors in Urban Mysuru
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作者 M.Rakesh sunil kumar +1 位作者 S.Kavya G.Hari PRAKASH 《Journal of Integrative Nursing》 2025年第2期78-82,共5页
Background:Hypertension is a significant public health concern and a leading cause of cardiovascular diseases worldwide.Urbanization has contributed to an increased prevalence of hypertension by introducing lifestyle-... Background:Hypertension is a significant public health concern and a leading cause of cardiovascular diseases worldwide.Urbanization has contributed to an increased prevalence of hypertension by introducing lifestyle-related risk factors such as physical inactivity,unhealthy dietary patterns,and stress.Region-specific tools for assessing hypertension risk factors are essential for designing effective public health interventions.Objectives:This study aimed to develop and validate a questionnaire to assess the risk factors for hypertension in the urban population of Mysuru and identify the prevalence of key modifiable and nonmodifiable risk factors.Materials and Methods:A cross-sectional study was conducted among 100 participants aged 18-60 years in urban Mysuru.A 40-item questionnaire was developed based on literature review and expert input.It included domains such as sociodemographic factors,lifestyle habits,and clinical history.Reliability was evaluated using Cronbach’s alpha,while construct validity was assessed through exploratory factor analysis.Descriptive statistics and Chi-square tests were used for data analysis.Results:The questionnaire demonstrated high internal consistency(Cronbach’s alpha>0.7)and satisfactory construct validity.Key findings included a high prevalence of low physical activity(60%),high salt intake(50%),and overweight individuals(30%).In addition,40%of participants reported a family history of hypertension,and 18%had prediabetes.These findings emphasize the role of modifiable risk factors in the rising hypertension burden in urban settings.Conclusion:The developed and validated questionnaire is a reliable and valid tool for assessing hypertension risk factors in urban populations. 展开更多
关键词 HYPERTENSION public health intervention questionnaire development risk factors urban population
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Hydro-Alcoholic Leaf Extract and Fractions of Codiaeum variegatum (var. Mollucanum) Exhibited an Improved Anti-Amoebic and Moderate Anti-Oxidant Potential
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作者 Sylvain Pechangou Nsangou Carine Matsingang Fondjou +5 位作者 Charifa Ngbetnkom Mandou sunil kumar Mfotie Njoya Emmanuel Frederic Nico Njayou Rakesh Sehgal Paul Fewou Moundipa 《American Journal of Plant Sciences》 CAS 2023年第3期339-356,共18页
Amoebiasis, classified as the third intestinal parasitic infection, represents a public health problem in low-income countries where hygiene and sanitation conditions are poor. With the resurgence of resistant pathoge... Amoebiasis, classified as the third intestinal parasitic infection, represents a public health problem in low-income countries where hygiene and sanitation conditions are poor. With the resurgence of resistant pathogenic strains as well as ancestral considerations in developing countries such as Cameroon, many people rely on medicinal plants to treat a plethora of diseases. This work aimed to highlight the anti-amoebic and anti-oxidant potential of Codiaeum variegatum extracts and fractions. The anti-amoebic potential of C. variegatum was assayed on the polyxenic culture of the clinical isolates of E. histolytica. Then, the anti-oxidant potential of the ethanolic/hydroethanolic extracts and fractions was evaluated through DPPH radical scavenging, iron reduction (FRAP), lipid peroxidation inhibitory potential and total antioxidant capacity tests followed by the determination of phenolic compound and flavonoid content. It was found that the fractionation process decreased the amoebicidal activities of C. variegatum leaf extracts. However hydroethanolic extract (CI<sub>50</sub>: 10.08 ± 0.42, 5.18 ± 0.09, 5.18 ± 0.09 μg/mL respectively after 24, 48 and 72 hours) was more active than ethanolic extract (CI<sub>50</sub>: 15.59 ± 6.17;9.61 ± 2.37;6.26 ± 3.22 μg/mL respectively after 24, 48 and 72 hours). Interestingly, the activities of hydroethanolic extract were significantly non-different compared to metronidazole CI<sub>50</sub>: 8.42 ± 0.44, 6.45 ± 0.22 and 3.42 ± 0.33 μg/mL, respectively after 24, 48 and 72 hours). Ethanolic extract and EF5 showed higher Phenolic compound contents and higher antioxidant activity than hydroethanolic extract and other fractions through DPPH radical scavenging power (EC50 = 311.50 ± 4.12 μg/mL) and total antioxidant capacity (44 ± 0.07 mgEAA/gF). However, these activities are significantly lower than those of ascorbic acid (EC50 = 31.20 ± 4.39 μg/mL, and 61.34 ± 4.42 μg/mL respectively). This low antioxidant activity was confirmed by poor phenolic and flavonoid compounds contents found in the extracts and fractions. The present result brings a new approach to the ethnopharmacological uses of C. variegatum against dysentery in cases associated with Amoebiasis in Cameroun. 展开更多
关键词 Codiaeum Variegatum AMOEBIASIS Antiamoebic Antioxidant
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Neovascular Glaucoma: An Update on Etiopathogenesis, Diagnostics and Management
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作者 sunil kumar Sujata kumari Ajay kumar Sinha 《Open Journal of Ophthalmology》 2022年第3期242-258,共17页
Neovascular glaucoma (NVG) is a severe secondary and refractory *severe secondary conditio, that accounts for a varying prevalence between 0.01% to 5.1% of all glaucoma those studied in different regions of the world.... Neovascular glaucoma (NVG) is a severe secondary and refractory *severe secondary conditio, that accounts for a varying prevalence between 0.01% to 5.1% of all glaucoma those studied in different regions of the world. **This is a pathological condition, which is caused by the new vessels over iris surface and followed by fibrovascular membrane formation over the trabecular meshwork, secondary to a local angiogenic stimulus. The fibrovascular membrane over trabecular meshwork obstructs the aqueous outflow at an angle of the anterior chamber. ***The obstruction in outflow of the aqueous results increase of intraocular pressure (IOP), within the eyeball. NVG results from a number of ocular and systemic conditions with retinal ischemia leading to anoxia as a mediator in over 95% of cases. Most of them are affected with proliferative diabetic retinopathy (PDR) followed by central retinal venous occlusion (CRVO), and ocular ischemic syndrome (OIS) along with other uncommon causes or all those causes that causes retinal anoxia which led to angiogenic activity in retina and iris of eye. Although NVG overall prevalence is low, but it is a dreadful condition led to blindness. The objective of this review is to provide detailed information on its basic and clinical aspects, to enable us to manage it logically. Here its etiopathogenesis, methods of early diagnosis and management are discussed. It was concluded that if NVG is detected earlier and managed systematically (both medical and surgical) along with an eye on alleviation of different aggravating factors of the retinal hypoxia, it could be a sight-saving measure to the affected person. 展开更多
关键词 Neovascular Glaucoma Rubeosis Iridis Retinal Hypoxia Diabetic Retinopa-thy Central Retinal Venous Occlusion Ocular Ischemic Syndrome
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Aorto-Pulmonary Artery Fistula Following Aortic Valve Replacement: A Diagnostic Dilemma
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作者 Tarun Raina Ramman Shyamveer Khangarot +2 位作者 sunil kumar M. A. Geelani D. K. Satsangi 《World Journal of Cardiovascular Surgery》 2016年第3期40-43,共4页
Aorto-pulmonary artery fistula is a rare and lethal occurrence after thoracic surgery and aortic aneurysms. Here we present a rare occurrence of acute aorto-pulmonary artery fistula in outpatient department in a follo... Aorto-pulmonary artery fistula is a rare and lethal occurrence after thoracic surgery and aortic aneurysms. Here we present a rare occurrence of acute aorto-pulmonary artery fistula in outpatient department in a follow up patient of aortic valve replacement and discuss challenges faced in diagnosis, etiopathogenesis and management. 展开更多
关键词 Aorto-Pulmonary Fistula Aortic Valve Replacement RARE COMPLICATIONS
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In vitro meat production: Challenges and benefits over conventional meat production 被引量:26
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作者 Zuhaib Fayaz Bhat sunil kumar Hina Fayaz 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第2期241-248,共8页
In vitro meat production system is the production of meat outside the food animals by culturing the stem cells derived from farm animals inside the bioreactor by using advanced tissue engineering techniques. Besides w... In vitro meat production system is the production of meat outside the food animals by culturing the stem cells derived from farm animals inside the bioreactor by using advanced tissue engineering techniques. Besides winning the favour of animal rights activists for its humane production of meat, in vitro meat production system also circumvents many of the issues associated with conventional meat production systems, like excessively brutal slaughter of food animals, nutrition-related diseases, foodborne illnesses, resource use, antibiotic-resistant pathogen strains, and massive emissions of methane that contribute to global warming. As the conditions in an in vitro meat production system are controlled and manipulatable, it will be feasible to produce designer, chemically safe and disease-free meat on sustainable basis. However, many challenges are to be faced before cultured meat becomes commercially feasible. Although, the production cost and the public acceptance are of paramount importance, huge funds are desperately required for further research in the field. 展开更多
关键词 in vitro meat HISTORY advantages techniques problems
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Structural characterization of monoterpene indole alkaloids in ethanolic extracts of Rauwolfia species by liquid chromatography with quadrupole time-of-flight mass spectrometry 被引量:8
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作者 sunil kumar Awantika Singh +3 位作者 Vikas Bajpai Mukesh Srivastava Bhim Pratap Singh Brijesh kumar 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第6期363-373,共11页
Rauwolfia species(Apocynaceae) are medicinal plants well known worldwide due to its potent bioactive monoterpene indole alkaloids(MIAs) such as reserpine,ajmalicine,ajmaline,serpentine and yohimbine.Reserpine,ajmalici... Rauwolfia species(Apocynaceae) are medicinal plants well known worldwide due to its potent bioactive monoterpene indole alkaloids(MIAs) such as reserpine,ajmalicine,ajmaline,serpentine and yohimbine.Reserpine,ajmalicine and ajmaline are powerful antihypertensive,tranquilizing agents used in hypertension.Yohimbine is an aphrodisiac used in dietary supplements.As there is no report on the comparative and comprehensive phytochemical investigation of the roots of Rauwolfia species,we have developed an efficient and reliable liquid chromatography-tandem mass spectrometry(LC–MS/MS) method for ethanolic root extract of Rauwolfia species to elucidate the fragmentation pathways for dereplication of bioactive MIAs using highperformance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry(HPLC–ESI–QTOF–MS/MS) in positive ion mode.We identified and established diagnostic fragment ions and fragmentation pathways using reserpine,ajmalicine,ajmaline,serpentine and yohimbine.The MS/MS spectra of reserpine,ajmalicine,and ajmaline showed C-ring-cleavage whereas E-ring cleavage was observed in serpentine via Retro Diels Alder(RDA).A total of 47 bioactive MIAs were identified and characterized on the basis of their molecular formula,exact mass measurements and MS/MS analysis.Reserpine,ajmalicine,ajmaline,serpentine and yohimbine were unambiguously identified by comparison with their authentic standards and other 42 MIAs were tentatively identified and characterized from the roots of Rauwolfia hookeri,Rauwolfia micrantha,Rauwolfia serpentina,Rauwolfia verticillata,Rauwolfia tetraphylla and Rauwolfia vomitoria.Application of LC–MS followed by principal component analysis(PCA) has been successfully used to discriminate among six Rauwolfia species. 展开更多
关键词 Rauwolfia SPECIES MONOTERPENE INDOLE ALKALOIDS (MIAs) HPLC–ESI–QTOF–MS/MS Principal component analysis (PCA)
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Identification and characterization of phenolics and terpenoids from ethanolic extracts of Phyllanthus species by HPLC-ESI-QTOF-MS/MS 被引量:11
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作者 sunil kumar Awantika Singh Brijesh kumar 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2017年第4期214-222,共9页
Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid... Phyllanthus species plants are a rich source of phenolics and widely used due to their medicinal properties. A liquid chromatography–tandem mass spectrometry(LC–MS/MS) method was developed using high-pressure liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry(HPLC-ESI-QTOFMS/MS) for the identification and characterization of quercetin, kaempferol, ellagic acid and their derivatives in ethanolic extracts of Phyllanthus species. The chromatographic separation was carried out on Thermo Betasil C_8 column(250 mm×4.5 mm, 5 μm) using 0.1% formic acid in water and 0.1% formic acid in methanol as the mobile phase. The identification of diagnostic fragment ions and optimization of collision energies were carried out using 21 reference standards. Totally 51 compounds were identified which include 21 compounds identified and characterized unambiguously by comparison with their authentic standards and the remaining 30 were tentatively identified and characterized in ethanolic extracts of P. emblica, P. fraternus, P. amarus and P.niruri. 展开更多
关键词 PHYLLANTHUS SPECIES HPLC-ESI-QTOF-MS/MS Phenolics
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Antidiabetic activity of methanolic bark extract of Alhizia odoratissima Benth.in alloxan induced diabetic albino mice 被引量:7
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作者 Dinesh kumar sunil kumar +2 位作者 Sonia Kohli Renu Arya Jyoti Gupta 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第11期900-903,共4页
Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any tre... Objective:To evaluate the antidiabetic potential of methanolic extract of Albizia odoratissima Benth.bark in alloxan induced diabetic mice.Methods:Group-Ⅰ(normal control) mice received only basal diet without any treatment.In Group-Ⅱ(Diabetic control) mice,diabetes was induced by alloxan(150 mg/kg i.p.) and received only Tween 80.5%v/v in normal saline. Group-Ⅲand Group-Ⅳmice received metformin(10 mg/kg) and gliclazide(10 mg/kg) as standard drugs.Group-ⅤandⅥmice received methanolic bark extract of Albizia odoratissima at doses of 250 and 500 mg/kg body weight p.o.,respectively.Results:The results of the study indicates that Albizia odoratissima bark extract significantly(P【0.01) reduced the blood sugar level.The bark extract also significantly reduced the levels of serum cholesterol,triglycerides, serum glutamic-oxaloacetic transaminase,serum glutamic-pyruvic transaminase,alkaline phosphatase and decreases level of total proteins in alloxan induced diabetic mice.Conclusions: Methanolic extract of Albizia odoratissima has protective effects on the protection of vital tissues(pancreas,kidney,liver,heart and spleen),thereby reducing the causation of diabetes in experimental animals. 展开更多
关键词 Albizia odoratissima ANTIDIABETIC potential Methanolic EXTRACT ALLOXAN MICE
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Mortality and morbidity in necrotizing pancreatitis managed on principles of step-up approach:7 years experience from a single surgical unit 被引量:12
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作者 Deshpande Aparna sunil kumar Shukla Kamalkumar 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2017年第10期200-208,共9页
AIM To determine percentage of patients of necrotizing pancreatitis(NP) requiring intervention and the types of interventions performed. Outcomes of patients of step up necrosectomy to those of direct necrosectomy wer... AIM To determine percentage of patients of necrotizing pancreatitis(NP) requiring intervention and the types of interventions performed. Outcomes of patients of step up necrosectomy to those of direct necrosectomy were compared. Operative mortality, overall mortality, morbidity and overall length of stay were determined. METHODS After institutional ethics committee clearance and waiver of consent, records of patients of pancreatitis were reviewed. After excluding patients as per criteria, epidemiologic and clinical data of patients of NP was noted. Treatment protocol was reviewed. Data of patients in whom stepup approach was used was compared to those in whom it was not used. RESULTS A total of 41 interventions were required in 39% patients. About 60% interventions targeted the pancreatic necrosis while the rest were required to deal with the complications of the necrosis. Image guided percutaneous catheter drainage was done in 9 patients for infected necrosis all of whom required further necrosectomy and in 3 patients with sterile necrosis. Direct retroperitoneal or anterior necrosectomy was performed in 15 patients. The average time to first intervention was 19.6 d in the non step-up group(range 11-36) vs 18.22 d in the Step-up group(range 13-25). The average hospital stay in non step-up group was 33.3 d vs 38 d in step up group. The mortality in the step-up group was 0%(0/9) vs 13%(2/15) in the non step up group. Overall mortality was 10.3% while post-operative mortality was 8.3%. Average hospital stay was 22.25 d.CONCLUSION Early conservative management plays an important role in management of NP. In patients who require intervention, the approach used and the timing of intervention should be based upon the clinical condition and local expertise available. Delaying intervention and use of minimal invasive means when intervention is necessary is desirable. The step-up approach should be used whenever possible. Even when the classical retroperitoneal catheter drainage is not feasible, there should be an attempt to follow principles of step-up technique to buy time. The outcome of patients in the step-up group compared to the non stepup group is comparable in our series. Interventions for bowel diversion, bypass and hemorrhage control should be done at the appropriate times. 展开更多
关键词 Necrotizing pancreatitis Nerosectomy Morbidity and mortality in necrotizing pancreatitis Step-up approach
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Antidiabetic,hypolipidemic and histopathological analysis of Dillenia indica (L.) leaves extract on alloxan induced diabetic rats 被引量:4
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作者 sunil kumar Vipin kumar Om Prakash 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第5期347-352,共6页
Objective:To investigate antidiabetic,hypolipidemic histopathological analysis of Dillenia indica(D.indica) methanolic leaves(DIME) extract in alloxan induced diabetic rat by administering oral doses(250 and 500 mg/kg... Objective:To investigate antidiabetic,hypolipidemic histopathological analysis of Dillenia indica(D.indica) methanolic leaves(DIME) extract in alloxan induced diabetic rat by administering oral doses(250 and 500 mg/kg body weight).Methods:Blood glucose levels were measured using blood glucose test strips with elegance glucometer on weekly intervals till the end of study(i.e.3 weeks).Other parameters e.g.liver profile,renal profile and total lipid levels were determined in normal and alloxan induced diabetic rats after oral administration of the extract for 21 days.Histopathological changes in diabetic rat organs(pancreas,liver and kidney) were also observed after extract treatment Results:Daily oral administration DIME(250 and 500 mg/kg body weight) and glibenclamide(10 mg/kg) showed beneficial effects on blood glucose level (P【0.001) as well as improving kidney,liver functions and hyperlipidaemia due to diabetes. The extract treatment also showed to enhanced serum insulin level and body weight of diabetic rats as compared to diabetic control group.Furthermore,the extract has a favorable effect on the histopathological changes of the pancreas,liver and kidney in alloxan induced diabetes. Conclusions:D.indica possess antidiabetic property as well improve body weight,liver profile, renal profile and total lipid levels.DIME has also favorable effect to inhibit the histopathological changes of the pancreas and kidney in alloxan induced diabetes. 展开更多
关键词 ANTIDIABETIC Dillenia INDICA HYPOLIPIDEMIC Rat Serum CHOLESTEROL
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New homotopy analysis transform method for solving the discontinued problems arising in nanotechnology 被引量:4
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作者 M.M.Khader sunil kumar S.Abbasbandy 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第11期135-139,共5页
We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential-difference equations. The proposed method is based on t... We present a new reliable analytical study for solving the discontinued problems arising in nanotechnology. Such problems are presented as nonlinear differential-difference equations. The proposed method is based on the Laplace trans- form with the homotopy analysis method (HAM). This method is a powerful tool for solving a large amount of problems. This technique provides a series of functions which may converge to the exact solution of the problem. A good agreement between the obtained solution and some well-known results is obtained. 展开更多
关键词 discretized mKdV lattice equation nonlinear differential-difference equations Laplace transform homotopy analysis transform method
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Neglected scrub typhus:An updated review with a focus on omics technologies 被引量:3
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作者 Dixit Sharma Ankita Sharma +2 位作者 Birbal Singh sunil kumar Shailender kumar Verma 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2022年第12期531-541,共11页
Scrub typhus is a neglected disease and one of the most serious health problems in the Asia-Pacific region.The disease is caused by an obligate intracellular bacteria Orientia tsutsugamushi,which is transmitted by chi... Scrub typhus is a neglected disease and one of the most serious health problems in the Asia-Pacific region.The disease is caused by an obligate intracellular bacteria Orientia tsutsugamushi,which is transmitted by chigger bites or larval mite bites.Scrub typhus is a threat to billions of people worldwide causing different health complications and acute encephalitis in infants and growing children.The disease causes multiple organ failure and mortality rates may reach up to 70%due to a lack of appropriate healthcare.Currently available genome and proteome databases,and bioinformatics methods are valuable tools to develop novel therapeutics to curb the pathogen.This review discusses the state-of-the-art of information about Orientia tsutsugamushi-mediated scrub typhus and delineates the role of omics technologies to develop drugs against the pathogen.The role of proteome-wide in silico approaches for the identification of therapeutic targets is also highlighted. 展开更多
关键词 Orientia tsutsugamushi Scrub typhus Therapeutic targets Omics technologies Drug discovery
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