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白藜芦醇对重症急性胰腺炎大鼠肝脏的保护作用

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西安交通大学学报（医学版） 2009年第1期30卷 5-9页

作者：沙焕臣马清涌 jha rajiv kumar 徐复国马振华西安交通大学医学院第一附属医院肝胆外科陕西西安710061

目的探讨白藜芦醇对实验性重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠肝功能的保护作用。方法96只成年雄性SD大鼠随机分为假手术(shamoperation,SO)组、重症急性胰腺炎(SAP)组、地塞米松(dexamethasone,DEX)治疗组和白藜芦醇(r... 详细信息

目的探讨白藜芦醇对实验性重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠肝功能的保护作用。方法96只成年雄性SD大鼠随机分为假手术(shamoperation,SO)组、重症急性胰腺炎(SAP)组、地塞米松(dexamethasone,DEX)治疗组和白藜芦醇(resveratrol,RES)治疗组。各组大鼠均于制模后3、6、12h采集标本。生化方法进行肝功能测定;酶联免疫吸附试验(enzyme linked i mmunosorbent assay,ELISA)测定血清TNF-α和IL-6含量;透射电镜观察胰腺和肝脏超微结构的变化;RT-PCR检测凋亡调控基因Bax、Bcl-2和caspase-3mRNA表达;Western Blot检测凋亡调控基因Bax、Bcl-2、caspase-3和线粒体内细胞色素C蛋白的表达。结果SAP组各时间点血清谷丙转氨酶(alanineaminotransferase,ALT)、谷草转氨酶(aspartate aminotransferase,AST)和总胆红素(total bilirubin,TBIL)水平均明显高于SO组(P0.05)。结论白藜芦醇可以降低SAP大鼠肝细胞凋亡的发生,从而起到减轻SAP介导的肝脏功能损伤的作用。

关键词：重症急性胰腺炎白藜芦醇肝功能损害 Bax Bcl-2 caspase-3 细胞色素C

猫眼草中科罗索酸对肝癌SMMC-7721细胞作用的研究

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世界科学技术-中医药现代化 2022年第9期24卷 3524-3531页

作者：张彦白思雨马建梅景维张蕾何昊郭增军拉吉姆西安医学院药学院西安710021 西安医学院中尼友好拉吉姆医学实验室西安710021 西安交通大学陕西省中医药管理局七药资源及抗肿瘤重点实验室西安710065

目的研究猫眼草活性单体的体外诱导人肝癌SMMC-7721细胞凋亡的作用与机制。方法以人肝癌SMMC-7721细胞为研究对象,MTT法测定猫眼草的活性单体科罗索酸对细胞的增殖作用的影响并考察不同浓度药物作用下的细胞形态。细胞划痕实验检测细胞... 详细信息

目的研究猫眼草活性单体的体外诱导人肝癌SMMC-7721细胞凋亡的作用与机制。方法以人肝癌SMMC-7721细胞为研究对象,MTT法测定猫眼草的活性单体科罗索酸对细胞的增殖作用的影响并考察不同浓度药物作用下的细胞形态。细胞划痕实验检测细胞迁移能力。流式细胞仪测定细胞凋亡和周期的情况。蛋白质免疫印迹(Western Blot)实验检测凋亡相关蛋白的表达。结果MTT实验结果显示科罗索酸对人肝癌SMMC-7721细胞抑制作用强于巨大戟醇但弱于盐酸阿霉素。对细胞形态学和细胞划痕、细胞凋亡实验证实了科罗索酸有抑制该细胞生长的作用。细胞周期检测发现低剂量的科罗索酸使人肝癌SMMC-7721细胞周期阻滞在S期,而高剂量的科罗索酸会使人肝癌SMMC-7721细胞阻滞在G0/G1期。Western Blot结果显示上调抑癌蛋白Bax表达、下调Bcl-2基因。结论猫眼草中的科罗索酸主要通过诱导细胞凋亡、阻滞细胞周期两个机制发挥抗肿瘤作用,是通过调控Bax/Bcl-2的表达来抑制肿瘤细胞的生长,是一种线粒体膜损伤导致的内源性路径调节。

关键词：猫眼草抗肿瘤 SMMC-7721

Adaptive Linear Quadratic Regulator for Continuous-Time Systems With Uncertain Dynamics

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IEEE/CAA Journal of Automatica Sinica 2020年第3期7卷 833-841页

作者： Sumit kumar jha Shubhendu Bhasin IEEE Department of Electronics and Communication Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj-211004India Department of Electrical Engineering Indian Institute of Technology DelhiNew Delhi-110016India

In this paper, adaptive linear quadratic regulator(LQR) is proposed for continuous-time systems with uncertain dynamics. The dynamic state-feedback controller uses inputoutput data along the system trajectory to continuously adapt and converge to the optimal controller. The result differs from previous results in that the adaptive optimal controller is designed without the knowledge of the system dynamics and an initial stabilizing policy. Further, the controller is updated continuously using input-output data, as opposed to the commonly used switched/intermittent updates which can potentially lead to stability issues. An online state derivative estimator facilitates the design of a model-free controller. Gradient-based update laws are developed for online estimation of the optimal gain. Uniform exponential stability of the closed-loop system is established using the Lyapunov-based analysis, and a simulation example is provided to validate the theoretical contribution.

关键词： Adaptive optimal control continuous policy update linear quadratic regulator uncertain system dynamics

Temporal patterns of storage and flux of N and P in young Teak plantations of tropical moist deciduous forest,India

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Journal of Forestry Research 2014年第1期25卷 75-86页

作者： Kaushalendra kumar jha Technical Forestry Indian Institute of Forest Management

Teak （Tectona grandis Linn. f.） ranks among the top five tropical hardwood species and is being promoted for use in plantations in its non-native range due to its high economic value. However, there is a general lack of data on ecosystem functioning of teak plantations. We aimed at understanding storage and flux of nutrients related to young plantations of teak. Cycling of nitrogen （N） and phosphorus （P） in a chronosequence of plantations （1, 5, 11, 18, 24 and 30 years） was studied in the Moist Deciduous Forest Region of North India with the objective of investigating the nutrient cycling pattern at younger age since the current trend of harvesting age of the species in several tropical countries is being drastically reduced for quick return from this high value crop. Standing state, nutrient uptake, nutrient return and nutrient retransloca-tion in these plantations were estimated by tree harvesting and chemical analysis methods. The range of total standing nutrient across all these plantations was 20.3 to 586.6 kg？ha-1 for N and 5.3 to 208.8 kg？ha-1 for P. Net uptake of N ranged from 19.4 to 88.9 kg？ha-1？a-1 and P from 3.8 to 18.1 kg？ha-1？a-1. Retranslocation of N and P among all the stands ranged from 8.7 to 48.0 kg？ha-1？a-1 and 0.01 to 3.5 kg？ha-1？a-1, respectively. Range of total nutrient return was 25.8 to 91.3 kg？ha-1？a-1 for N and 2.7 to 10.1 kg？ha-1？a-1 for P. N and P use efficiency was between 107.4 and 192.5 g dry organic matter （OM） g-1N, and 551.9 and 841.1 g OM g-1P, respec-tively. The turnover time ranged from 2.04-13.17 years for N and be-tween 2.40-22.66 years for P. Quantity of N and P in the soil nutrient pool ranged from 2566.8 to 4426.8 kg？ha-1 and 372 to 520 kg？ha-1, re-spectively. Storage and flux of components in different plant parts of different aged plantations were assessed and depicted in compartment models. Percentage storage in soil, litter and vegetation ranged from 82% to 99%, 0.6% to 2.4% and 0.5% to 15% for N, respectively, and from

关键词： nutrient uptake standing state return turnover time nutrient use efficiency compartment model harvest loss Tectona grandis

Biomass production and carbon balance in two hybrid poplar(Populus euramericana)plantations raised with and without agriculture in southern France

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Journal of Forestry Research 2018年第6期29卷 1689-1701页

作者： Kaushalendra kumar jha UMR Systems Institute Nationale de la Recherche Agronomique2 place Pierre Viala34060 MontpellierFrance Technical Forestry Indian Institute of Forest ManagementBhopalIndia

Poplar is useful in different climates for bioenergy production and carbon sequestration when planted as a single species or in agroforestry. Europe has large areas potentially suitable for poplar forestry and a bioenergy policy that would encourage poplar forestry. In this study I estimated biomass production and carbon sequestration in poplar monoculture plantation and poplar-wheat agroforestry, in the Mediterranean region of France. A single-tree harvesting method was used to estimate biomass and an empirical conversion factor was adopted to calculate sequestered carbon. Total biomass was higher in agroforestry trees(1223 kg tree) than in monoculture plantation trees(1102 kg tree).Aboveground and belowground biomass distributions were similar in both cases(89 and 88% aboveground, and 11 and12% belowground, respectively in agroforestry and monoculture). The partitioning of total biomass in an agroforestry tree in leaves, branch, and trunk(aboveground), and fine roots, medium roots, coarse roots and underground stem(belowground) was 1,22,and 77,and 6,9, 44 and 40%,respectively. Except for branch and trunk, all other compartments were similarly distributed in a monoculture *** of C was higher in agroforestry trees(612 kg tree)than in monoculture trees(512 kg tree). In contrast, C storage on a per hectare basis was lower in agroforestry(85 Mg ha) than in monoculture(105 Mg ha) due to the lower density of trees per hectare in agroforestry(139 trees in agroforestry vs 204 trees in monoculture). On a per hectare basis, soil C stocks pattern were similar to per tree stocking:They were higher in agroforestry at 330 Mg hathan in monoculture 304 Mg ha. Higher C accumulation by agroforestry has a direct management implication in the sense that expanding agroforestry into agriculture production areas with short rotation and fast growing trees like poplar would encourage quicker and greater C sequestration. This could simultaneously fulfil the requirement of bioenergy

关键词： Populus euramericana Wood volume and density Root:shoot ratio Vegetation and soil carbon System efficiency

Carbon storage and sequestration rate assessment and allometric model development in young teak plantations of tropical moist deciduous forest, India

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Journal of Forestry Research 2015年第3期26卷 589-604页

作者： Kaushalendra kumar jha Technical Forestry Indian Institute of Forest ManagementPO Box No. 357 Nehru Nagar Bhopal 462 003 MP India

Carbon （C） sequestration through plantations is one of the important mitigation measures for rising levels of carbon dioxide and other greenhouse gases in the atmosphere. This study aimed to assess C stocks and their sequestration rate, and to develop allometric models for estimation of C stocking in age-series young teak （Tectona grandis） planta- tions （1, 5, 11, 18, 24 and 30 years） by using biomass and productivity estimation and regression, respectively. These plantations were raised in tropical moist deciduous forests of Kumaun Himalayan tarai. Total C stocks estimated for these plantations were 1.6, 15.8, 35.4, 39.0, 61.5 and 73.2 Mg ha-1, respectively. Aboveground and belowground C storage in- creased with increasing plantation age; however, the range of their percentage contribution showed little variation （87.8-88.2 and 11.7-12.7 %, respectively）, The rate of C sequestration for these respective plantations was 1.06, 6.95, 5.46, 5.42, 3.39 and 5.37 Mg ha-1 a-1. Forty percent of the aboveground annual storage was retained in the tree while 60 % was released in the form of foliage, twigs, and fruit litter. In the case of total （tree） annual production, 43 % was retained while 57 % was released as litter including root. C stock, C sequestration rate, accumulation ratio （1.4-18.1）, root：shoot C ratio （0.61--0.13） and production efficiency （0.01-0.18） were comparable to some previous reports for other species and forests. These data could be useful in deciding the harvesting age for young teak with respect to C storage and sequestrationrate. Four allometric models using linear regression equations were developed between biomass （twice the C stock） and diameter, girth, and height of the tree at different ages. The diameter model was found more suitable for C stock predic- tion in similar areas.

关键词： Age series Biomass Carbon budget DBH Productivity Production ratios Regression equations -Tectona grandis

Proactive Connection Recovery Strategy with Recovery Time Constraint for Survivable Elastic Optical Networks

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China Communications 2021年第9期18卷 236-248页

作者： Dinesh kumar rajiv kumar Neeru Sharma Department of Electronics&Communication Engineering Jaypee University of Information Technology WaknaghatSolan(HP)India

This paper presents a halfway signaling exchange shared path protection(HSE-SPP)on the backup route for a fast connection recovery *** the proposed HSE-SPP,a pre-assigned intermediate node on the backup route is chosen for signaling *** connection fails,source and destination nodes simultaneously generate backup connection setup messages to the pre-assigned intermediate node on the reserved backup *** the intermediate node,signaling process occurs,and acknowledgment is generated for data transmission to the respective end ***,connection recovery time by applying HSE-SPP becomes very *** are performed for network parameters and results are verified with existing *** average recovery time(RT),bandwidth blocking probability(BBP),bandwidth provisioning ratio(BPR),and resource overbuild(RO)ratio of HSE-SPP for ARPANET is 13.54 ms,0.18,3.02,0.55,and for dedicated path protection(DPP)are 13.20 ms,0.56,6.30,3.75 and for shared path protection(SPP)22.19 ms,0.22,3.23,0.70 ***,average RT,BBP,BPR and RO of HSE-SPP for COST239 are8.33 ms,0.04,1.64,0.26,and for DPP 4.23,0.47,3.50,2.04,and for SPP 11.81,0.08,1.66,0.27 ***,results of the proposed strategy are better in terms of RT,BBP,BPR,and RO ratio.

关键词： routing and spectrum assignment halfway signaling exchange-shared path protection(HSE-SPP) dedicated path protection bandwidth blocking probability(BBP)

Synthetic and biological studies on a cyclopolypeptide of plant origin

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第5期9卷 391-400页

作者： rajiv DAHIYA Akhilesh kumar Department of Pharmaceutical Chemistry Rajiv Academy for Pharmacy

Objective:A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling of tetrapep-tide units Boc-Leu-Pro-Trp-Leu-OMe and Boc-Ile-Ala-Ala-Gly-OMe after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment. Methods:Solution phase technique was adopted for the synthesis of cyclooctapeptide-sarcodactylamide. Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz. Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-OMe and Ala-Gly-OMe. Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method. The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis. The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities. Results:Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide(DCC) as coupling agent. Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites(DLA) and Ehrlich's ascites carcinoma(EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp. Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin. Conclusion:Solution phase technique employing DCC and triethylamine(TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide. N-methyl morpholine(NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine.

关键词： Cyclic octapeptide Citrus medica var. sarcodactylis Sarcodactylamide Peptide synthesis Anthelmintic activity Antimicrobial activity Cytotoxicity

Optical anisotropy and the direction of polarization of exciton emissions in a semiconductor quantum dot:Effect of heavy-and light-hole mixing

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Chinese Physics B 2017年第8期26卷 400-406页

作者： Ranber Singh rajiv kumar Vikramjeet Singh Department of Physics Sri Guru Gobind Singh CollegeSector 26Chandigarh 160019India Department of Physics DAV University JalandharPunjab 144012India IKGPTU Campus HoshiarpurPunjab 146001India

The dependence of the directions of polarization of exciton emissions, fine structure splittings （FSS）, and polarization anisotropy on the light- and heavy-hole （LH-HH） mixing in semiconductor quantum dots （QDs） is investigated using a mesoscopic model. In general, all QDs have a four-fold exciton ground state. Two exciton states have directions of polarization in the growth-plane, while the other two are along the growth direction of the QD. The LH-HH mixing does affect the FSS and polarization anisotropy of bright exciton states in the growth-plane in the low symmetry QDs （e.g., C2v, CS, C1 ）, while it has no effect on the FSS and polarization anisotropy in high symmetry QDs （e.g., C3V, D2d）. When the hole ground state is pure HH or LH, the bright exciton states in the growth-plane are normal to each other. The LH-HH mixing affects the relative intensities and directions of bright exciton states in the growth-plane of the QD. The polarization anisotropy of exciton emissions in the growth-plane of the QD is independent of the phase angle of LH-HH mixing but strongly depends on the magnitude of LH-HH mixing in low symmetry QDs.

关键词： light-heavy hole mixing excitons quantum dots