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飞秒激光脉冲作用熔石英的超快传热动力学研究
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作者 余方锐 杜广庆 +3 位作者 waqas ahmad 陆宇 杨青 陈烽 《应用光学》 CAS 北大核心 2024年第3期529-536,共8页
飞秒激光具有超短脉冲宽度、超高峰值功率的特点,飞秒激光与物质作用表现出的非线性吸收和低热扩散特性,使其在高精密微纳器件加工中有着重要的应用前景。建立了针对飞秒激光脉冲与熔石英作用的瞬态光电离以及非平衡传热的超快动力学模... 飞秒激光具有超短脉冲宽度、超高峰值功率的特点,飞秒激光与物质作用表现出的非线性吸收和低热扩散特性,使其在高精密微纳器件加工中有着重要的应用前景。建立了针对飞秒激光脉冲与熔石英作用的瞬态光电离以及非平衡传热的超快动力学模型。通过数值求解该模型获得了飞秒激光单脉冲作用熔石英的载流子密度和非平衡电子与声子温度的时空演化;得到了在非平衡态条件下,电声耦合时间随激光能量密度、脉冲宽度的近线性调控规律。进一步研究得到了瞬态电子热导、热容、电声耦合系数的变化规律,并对上述模拟现象进行了分析和探讨。 展开更多
关键词 飞秒激光脉冲 瞬态光电离 超快传热 双温模型
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Carbon Monoxide Modulates Auxin Transport and Nitric Oxide Signaling in Plants under Iron Deficiency Stress
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作者 Kaiyue Hong Yasmina Radani +2 位作者 waqas ahmad Ping Li Yuming Luo 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第1期45-61,共17页
Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in mo... Carbon monoxide(CO)and nitric oxide(NO)are signal molecules that enhance plant adaptation to environmental stimuli.Auxin is an essential phytohormone for plant growth and development.CO and NO play crucial roles in modulating the plant’s response to iron deficiency.Iron deficiency leads to an increase in the activity of heme oxygenase(HO)and the subsequent generation of CO.Additionally,it alters the polar subcellular distribution of Pin-Formed 1(PIN1)proteins,resulting in enhanced auxin transport.This alteration,in turn,leads to an increase in NO accumulation.Furthermore,iron deficiency enhances the activity of ferric chelate reductase(FCR),as well as the expression of the Fer-like iron deficiency-induced transcription factor 1(FIT)and the ferric reduction oxidase 2(FRO2)genes in plant roots.Overexpression of the long hypocotyl 1(HY1)gene,which encodes heme oxygenase,or the CO donor treatment resulted in enhanced basipetal auxin transport,higher FCR activity,and the expression of FIT and FRO2 genes under Fe deficiency.Here,a potential mechanism is proposed:CO and NO interact with auxin to address iron deficiency stress.CO alters auxin transport,enhancing its accumulation in roots and up-regulating key iron-related genes like FRO2 and IRT1.Elevated auxin levels affect NO signaling,leading to greater sensitivity in root development.This interplay promotes FCR activity,which is crucial for iron absorption.Together,these molecules enhance iron uptake and root growth,revealing a novel aspect of plant physiology in adapting to environmental stress. 展开更多
关键词 Carbon monoxide nitric oxide AUXIN iron deficiency signal molecule PLANTS
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Use of Unmanned Aerial System (UAS) Phenotyping to Predict Pod and Seed Yield in Organic Peanuts
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作者 Aurora Manley Waltram Ravelombola +6 位作者 John Cason Brian Bennett Hanh Pham Emi Kimura Caroline Ruhl waqas ahmad Madeline Brown 《American Journal of Plant Sciences》 CAS 2023年第3期415-426,共12页
Peanut (Arachis hypogaea L.) is a highly nutritious food that is an excellent source of protein and is associated with increased coronary health, lower risk of type-2 diabetes, lower risk of breast cancer and a health... Peanut (Arachis hypogaea L.) is a highly nutritious food that is an excellent source of protein and is associated with increased coronary health, lower risk of type-2 diabetes, lower risk of breast cancer and a healthy profile of inflammatory biomarkers. The domestic demand for organic peanuts has significantly increased, requiring new breeding efforts to develop peanut varieties adapted to the organic farming system. The use of unmanned aerial system (UAS) has gained scientific attention because of the ability to generate high-throughput phenotypic data. However, it has not been fully investigated for phenotyping agronomic traits of organic peanuts. Peanuts are beneficial for cardio system protection and are widely used. Within the U.S., peanuts are grown in 11 states on roughly 600,000 hectares and averaging 4500 kg/ha. This study’s objective was to test the accuracy of UAS data in the phenotyping pod and seed yield of organic peanuts. UAS data was collected from a field plot with 20 Spanish peanut breeding lines on July 07, 2021 and September 27, 2021. The study was a randomized complete block design (RCBD) with 3 blocks. Twenty-five vegetation indices (VIs) were calculated. The analysis of variance showed significant genotypic effects on all 25 vegetation indices for both flights (p < 0.05). The vegetation index Red edge (RE) from the first flight was the most significantly correlated with both pod (r = 0.44) and seed yield (r = 0.64). These results can be used to further advance organic peanut breeding efforts with high-throughput data collection. 展开更多
关键词 PEANUT Unmanned Aerial System Vegetation Indices PHENOTYPING Pod Yield Seed Yield
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Wnt signaling pathway inhibitor promotes mesenchymal stem cells differentiation into cardiac progenitor cells in vitro and improves cardiomyopathy in vivo
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作者 Rabbia Muneer Rida-e-Maria Qazi +4 位作者 Abiha Fatima waqas ahmad Asmat Salim Luciana Dini Irfan Khan 《World Journal of Stem Cells》 SCIE 2023年第8期821-841,共21页
BACKGROUND Cardiovascular diseases particularly myocardial infarction(MI)are the leading cause of mortality and morbidity around the globe.As cardiac tissue possesses very limited regeneration potential,therefore use ... BACKGROUND Cardiovascular diseases particularly myocardial infarction(MI)are the leading cause of mortality and morbidity around the globe.As cardiac tissue possesses very limited regeneration potential,therefore use of a potent small molecule,inhibitor Wnt production-4(IWP-4)for stem cell differentiation into cardiomyocytes could be a promising approach for cardiac regeneration.Wnt pathway inhibitors may help stem cells in their fate determination towards cardiomyogenic lineage and provide better homing and survival of cells in vivo.Mesenchymal stem cells(MSCs)derived from the human umbilical cord have the potential to regenerate cardiac tissue,as they are easy to isolate and possess multilineage differentiation capability.IWP-4 may promote the differentiation of MSCs into the cardiac lineage.AIM To evaluate the cardiac differentiation ability of IWP-4 and its subsequent in vivo effects.METHODS Umbilical cord tissue of human origin was utilized to isolate the MSCs which were characterized by their morphology,immunophenotyping of surface markers specific to MSCs,as well as by tri-lineage differentiation capability.Cytotoxicity analysis was performed to identify the optimal concentration of IWP-4.MSCs were treated with 5μM IWP-4 at two different time intervals.Differentiation of MSCs into cardiomyocytes was evaluated at DNA and protein levels.The MI ratmodel was developed.IWP-4 treated as well as untreated MSCs were implanted in the MI model,then the cardiac function was analyzed via echocardiography.MSCs were labeled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate(DiI)dye for tracking,while the regeneration of infarcted myocardium was examined by histology and immunohistochemistry.RESULTS MSCs were isolated and characterized.Cytotoxicity analysis showed that IWP-4 was non-cytotoxic at 5μM concentration.Cardiac specific gene and protein expression analyses exhibited more remarkable results in fourteen days treated group that was eventually selected for in vivo transplantation.Cardiac function was restored in the IWP-4 treated group in comparison to the MI group.Immunohistochemical analysis confirmed the homing of pre-differentiated MSCs that were labeled with DiI cell labeling dye.Histological analysis confirmed the significant reduction in fibrotic area,and improved left ventricular wall thickness in IWP-4 treated MSC group.CONCLUSION Treatment of MSCs with IWP-4 inhibits Wnt pathway and promotes cardiac differentiation.These pre-conditioned MSCs transplanted in vivo improved cardiac function by cell homing,survival,and differentiation at the infarcted region,increased left ventricular wall thickness,and reduced infarct size. 展开更多
关键词 Myocardial infarction Inhibitor Wnt production-4 DIFFERENTIATION Mesenchymal stem cells Wnt pathway Cardiac function
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Aspect-Based Sentiment Classification Using Deep Learning and Hybrid of Word Embedding and Contextual Position
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作者 waqas ahmad Hikmat Ullah Khan +3 位作者 Fawaz Khaled Alarfaj Saqib Iqbal Abdullah Mohammad Alomair Naif Almusallam 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期3101-3124,共24页
Aspect-based sentiment analysis aims to detect and classify the sentiment polarities as negative,positive,or neutral while associating them with their identified aspects from the corresponding context.In this regard,p... Aspect-based sentiment analysis aims to detect and classify the sentiment polarities as negative,positive,or neutral while associating them with their identified aspects from the corresponding context.In this regard,prior methodologies widely utilize either word embedding or tree-based rep-resentations.Meanwhile,the separate use of those deep features such as word embedding and tree-based dependencies has become a significant cause of information loss.Generally,word embedding preserves the syntactic and semantic relations between a couple of terms lying in a sentence.Besides,the tree-based structure conserves the grammatical and logical dependencies of context.In addition,the sentence-oriented word position describes a critical factor that influences the contextual information of a targeted sentence.Therefore,knowledge of the position-oriented information of words in a sentence has been considered significant.In this study,we propose to use word embedding,tree-based representation,and contextual position information in combination to evaluate whether their combination will improve the result’s effectiveness or not.In the meantime,their joint utilization enhances the accurate identification and extraction of targeted aspect terms,which also influences their classification process.In this research paper,we propose a method named Attention Based Multi-Channel Convolutional Neural Net-work(Att-MC-CNN)that jointly utilizes these three deep features such as word embedding with tree-based structure and contextual position informa-tion.These three parameters deliver to Multi-Channel Convolutional Neural Network(MC-CNN)that identifies and extracts the potential terms and classifies their polarities.In addition,these terms have been further filtered with the attention mechanism,which determines the most significant words.The empirical analysis proves the proposed approach’s effectiveness compared to existing techniques when evaluated on standard datasets.The experimental results represent our approach outperforms in the F1 measure with an overall achievement of 94%in identifying aspects and 92%in the task of sentiment classification. 展开更多
关键词 Sentiment analysis word embedding aspect extraction consistency tree multichannel convolutional neural network contextual position information
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狂犬病病毒固定株感染对微管结合蛋白EB3表达的影响
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作者 宋颖 李莹莹 +5 位作者 陈云云 任严新 waqas ahmad 段铭 关振宏 张茂林 《中国预防兽医学报》 CAS CSCD 北大核心 2015年第5期330-333,共4页
为研究末端结合蛋白RP/EB家族成员3(EB3)在狂犬病病毒(RABV)感染引起大鼠神经元细胞骨架发生明显改变过程中的变化情况,本研究采用RABV固定株CVS感染大鼠原代神经元细胞,从转录及翻译水平分别对EB3进行检测,并通过免疫荧光观察EB3在神... 为研究末端结合蛋白RP/EB家族成员3(EB3)在狂犬病病毒(RABV)感染引起大鼠神经元细胞骨架发生明显改变过程中的变化情况,本研究采用RABV固定株CVS感染大鼠原代神经元细胞,从转录及翻译水平分别对EB3进行检测,并通过免疫荧光观察EB3在神经元细胞内的分布变化。结果显示,病毒感染6 h后,EB3转录和翻译水平有明显下调,EB3分布呈突起向胞体集中趋势,表明病毒可能通过对微管结合蛋白EB3的下调,使细胞骨架的稳定性降低。本实验结果为进一步研究RABV引起的神经元退行性病变机制奠定了基础。 展开更多
关键词 狂犬病病毒 EB3蛋白 细胞骨架 神经元细胞
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Oxidative desulfurization of dibenzothiophene over Fe promoted Co–Mo/Al_2O_3 and Ni–Mo/Al_2O_3 catalysts using hydrogen peroxide and formic acid as oxidants 被引量:3
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作者 Yaseen Muhammad Ayesha Shoukat +2 位作者 Ata Ur Rahman Haroon Ur Rashid waqas ahmad 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第3期593-600,共8页
This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al_2O_3 catalysts in the oxidative desulfurization(ODS) of dibenzothiophene(DBT) using H_2O... This work reports the enhancing effect of a highly cost effective and efficient metal, Fe, incorporation to Co or Ni based Mo/Al_2O_3 catalysts in the oxidative desulfurization(ODS) of dibenzothiophene(DBT) using H_2O_2 and formic acid as oxidants. The influence of operating parameters i.e. reaction time, catalyst dose, reaction temperature and oxidant amount on oxidation process was investigated. Results revealed that 99% DBT conversion was achieved at 60 °C and 150 min reaction time over Fe–Ni–Mo/Al_2O_3. Fe tremendously enhanced the ODS activity of Co or Ni based Mo/Al_2O_3 catalysts following the activity order: Fe–Ni–Mo/Al_2O_3 NFe–Co–Mo/Al_2O_3 NNi–Mo/Al_2O_3 NCo–Mo/Al_2O_3, while H_2O_2 exhibited higher oxidation activity than formic acid over all catalyst systems. Insight about the surface morphology and textural properties of fresh and spent catalysts were achieved using scanning electron microscopy(SEM), X-ray diffraction(XRD), energy dispersive X-ray(EDX)analysis, Atomic Absorption Spectroscopy(AAS) and BET surface area analysis, which helped in the interpretation of experimental data. The present study can be deemed as an effective approach on industrial level for ODS of fuel oils crediting to its high efficiency, low process/catalyst cost, safety and mild operating condition. 展开更多
关键词 Co-Mo/Al2O3 催化剂系统 氧化剂 氢过氧化物 FE 扫描电子显微镜 H2O2 反应时间
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Combination of mesenchymal stem cells and three-dimensional collagen scaffold preserves ventricular remodeling in rat myocardial infarction model 被引量:1
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作者 Rida-e-Maria Qazi Irfan Khan +5 位作者 Kanwal Haneef Tuba Shakil Malick Nadia Naeem waqas ahmad Asmat Salim Sadia Mohsin 《World Journal of Stem Cells》 SCIE 2022年第8期633-657,共25页
BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tis... BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model.Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control.Histological analysis also showed reduction in fibrotic scar,improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group.Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.CONCLUSION Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs,improves cell engraftment at the infarcted region,reduces infarct size and improves cardiac function. 展开更多
关键词 Mesenchymal stem cells Myocardial infarction Cardiac tissue engineering Demethylating agent Collagen scaffold ZEBULARINE
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Proliferation, Multiplication and Improvement of Micro-Propagation System for Mass Clonal Production of Rose through Shoot Tip Culture
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作者 Allah Jurio Khaskheli Muhammad Ibrahim Khaskheli +6 位作者 Maqsood ahmad Khaskheli Tahmina Shar waqas ahmad Umed Ali Lighari Muhammad Azeem Khaskheli Asad Ali Khaskheli Faisal Hayat Makan 《American Journal of Plant Sciences》 2018年第2期296-310,共15页
Present study was conducted to assess the regeneration potential and producing mass-clonal seedlings of Rose through shoot tip culture. A total of 40 explants were cultured on each of basal medium supplemented with di... Present study was conducted to assess the regeneration potential and producing mass-clonal seedlings of Rose through shoot tip culture. A total of 40 explants were cultured on each of basal medium supplemented with different concentrations of BAP, NAA and GA. The observations on the survival rate, days taken to initiate the shoots, total number of shoots and length of shoots, initiation of roots, total number of root, length of roots and number of leaves were investigated. Rose regenerated on MS-Basal medium (control) without addition of growth hormones showed significantly (P < 0.05) lower survival rate and did not show shoots up to the end of experiments. MS-Basal medium supplemented with different concentrations of BAP, NAA and GA showed increasing rate of survival. MS-Basal medium supplemented with highest BAP, NAA and GA concentration (MS-SV) has taken least time to initiate the shoots, whilst supplemented in concentrations of 0.5 and/or 1.0 mg/L, respectively revealed more time. Rooted plants were transplanted into the substrate and acclimatized in the laboratory greenhouse (humid cavity). The acclimatization in the humid cavity showed optimistic effect on the number of survived plants. 展开更多
关键词 ROSE Tissue Culture EXPLANTS BAP NAA and GA
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Initiation of Unmanned Aerial System (UAS) Phenotyping of Plant Height and Canopy Width in Guar
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作者 Waltram Ravelombola Aurora Manley +4 位作者 Caroline Ruhl Madeline Brown Hanh Pham Shubham Malani waqas ahmad 《American Journal of Plant Sciences》 CAS 2022年第12期1427-1438,共12页
The use of the Unmanned Aerial System (UAS) has attracted scientific attention because of its potential to generate high-throughput phenotyping data. The application of UAS to guar phenotyping remains limited. Guar is... The use of the Unmanned Aerial System (UAS) has attracted scientific attention because of its potential to generate high-throughput phenotyping data. The application of UAS to guar phenotyping remains limited. Guar is multi-purpose legume species. India and Pakistan are the world’s top guar producers. The U.S. is the world guar largest market with an import value of >$1 billion annually. The objective of this study was to test the feasibility of UAS phenotyping of plant height and canopy width in guar. The UAS data were collected from a field plot of 10 guar accessions on July 7, 2021, and September 27, 2021. The study was organized in a Randomized Complete Block Design (RCBD) with 3 blocks. A total of 23 Vegetation Indices (VIs) were computed. The analysis of variance showed significant genotypic effects on plant weight (p < 0.05) and canopy width (p on plant height (p most VIs were significant for both flights (p Vegetation Index (NDVI) and Red Edge Normalized Difference Vegetation Index (NDRE) were significantly and highly correlated with plant height (r = 0.74) and canopy width (r = 0.68). The results will be of interest in developing high throughput phenotyping approach for guar breeding. 展开更多
关键词 GUAR Unmanned Aerial System Vegetation Indices PHENOTYPING Plant Height Canopy Width
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Desulphurization of Transportation Fuels by Per-Formic Acid Oxidant Using MoOx Loaded on ZSM-5 Catalyst
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作者 waqas ahmad Imtiaz ahmad 《Journal of Power and Energy Engineering》 2017年第12期87-99,共13页
Desulphurization of model and real oil samples was investigated using performic acid as oxidant assisted by air as co-oxidant. The catalysts used were Mo-oxide supported on ZSM-5 zeolite, which was synthesized in the ... Desulphurization of model and real oil samples was investigated using performic acid as oxidant assisted by air as co-oxidant. The catalysts used were Mo-oxide supported on ZSM-5 zeolite, which was synthesized in the laboratory and characterized by FT-IR, XRD, SEM and SSA analysis. In case of model oil, the optimum condition determined for complete oxidation of all the model compounds including thiophene, DBT and 4,6-DMDBT were;60?C, 60 min, ambient pressure and air flow rate of 100 mL/min. The oxidation reactivity decreased from 4,6-DMDBT to DBT and thiophene, which was found to follow pseudo first order kinetics. The real oil sample used in the study included untreated naphtha (NP), light gas oil (LGO), heavy gas oil (HGO) and Athabasca bitumen (Bit.). In case of NP and LGO the sulfur removal of above 78% was attained whereas in case of HGO and Bit. samples about 60% of desulfurization was achieved. 展开更多
关键词 MOLYBDENUM Oxide NH4-ZSM-5 OXIDATIVE DESULPHURIZATION Air Oxidation Performic Acid Model Sulfur Compounds Wet-Impregnation
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Observability of parameter space for charged Higgs boson in its bosonic decays in two Higgs doublet model Type-1
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作者 Ijaz Ahmed waqas ahmad +1 位作者 M.S.Amjad Jamil Muhammad 《Chinese Physics C》 SCIE CAS CSCD 2024年第2期57-65,共9页
This study explores the possibility of discovering H±through its bosonic decays,i.e.,H±→W±φ(whereφ=h or A),within the Type-I two Higgs doublet model(2HDM).The main objective is to demonstrate the ava... This study explores the possibility of discovering H±through its bosonic decays,i.e.,H±→W±φ(whereφ=h or A),within the Type-I two Higgs doublet model(2HDM).The main objective is to demonstrate the available parameter space after applying recent experimental and theoretical exclusion limits.We suggest that mH±=150 GeV is the most probable mass for the H±→W±φdecay channel in pp collisions at s1/2=8,13,and 14 TeV.We also report on the application of a modern machine learning approach to a multivariate technique for heavy charged Higgs production in association with a single top quark through weak interaction to demonstrate its observability in comparison with the most relevant Standard Model backgrounds using the neural networks of boosted decision Tree(BDT),likelihood(LH),and multilayer perceptron(MLP). 展开更多
关键词 charged Higgs MSSM LHC
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Rab5与Rab7调控N2a细胞内狂犬病病毒的早期感染 被引量:3
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作者 李莹莹 王新宇 +5 位作者 陈云云 waqas ahmad 曹国燊 段铭 关振宏 张茂林 《中国兽医学报》 CAS CSCD 北大核心 2016年第5期768-771,共4页
狂犬病病毒(rabies virus,RABV)作为一种高度嗜神经性的病毒,通过网格蛋白介导和pH依赖的内吞途径侵入神经细胞,然后经胞内体途径进行传输。已有研究表明,Rab5和Rab7是介导胞内体分选、成熟及定向运输的关键蛋白,而RABV胞内运输是否也... 狂犬病病毒(rabies virus,RABV)作为一种高度嗜神经性的病毒,通过网格蛋白介导和pH依赖的内吞途径侵入神经细胞,然后经胞内体途径进行传输。已有研究表明,Rab5和Rab7是介导胞内体分选、成熟及定向运输的关键蛋白,而RABV胞内运输是否也受到这两者的调控尚不清楚。本试验通过免疫荧光、Western blot及TCID50等技术,检测了N2a中RABV核蛋白(N)和Rab5与Rab7的胞内共定位及RNAi下调Rab5与Rab7表达时,N蛋白表达水平、病毒滴度等的变化。结果发现,Rab5和Rab7与RABV N蛋白存在共定位;当Rab5和Rab7表达下调,RABV感染初期N蛋白表达显著下降,且病毒TCID50也随之降低。结果表明,RABV感染受Rab5和Rab7调节。为进一步解析狂犬病病毒逆轴浆传输机制提供了新的数据。 展开更多
关键词 Rab5 Rab7 狂犬病病毒 胞内体 早期感染
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狂犬病病毒入胞途径的初步探索 被引量:1
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作者 王新宇 郭艺迪 +6 位作者 高洁 赵铭昕 刘恩华 段铭 关振宏 waqas ahmad 张茂林 《中国兽医学报》 CAS CSCD 北大核心 2018年第3期502-507,共6页
狂犬病病毒(rabies virus,RABV)具有高度嗜神经性,通过识别细胞膜上特异性受体并借助内吞途径侵入细胞。为了探究其入胞途径,本研究在人神经瘤细胞(SH-SY5Y)和非洲绿猴肾上皮细胞(Vero)上,应用氯丙嗪(chlorpromazine)、制霉菌素... 狂犬病病毒(rabies virus,RABV)具有高度嗜神经性,通过识别细胞膜上特异性受体并借助内吞途径侵入细胞。为了探究其入胞途径,本研究在人神经瘤细胞(SH-SY5Y)和非洲绿猴肾上皮细胞(Vero)上,应用氯丙嗪(chlorpromazine)、制霉菌素(nystatin)、巴弗洛霉素a1(bafilomycin a1)、dynasore等抑制剂处理细胞后,进行RABV感染,通过检测病毒N基因拷贝数和RABV效价,对RABV入胞途径进行初步探究。结果显示,RABV通过网格蛋白介导、低pH值和发动蛋白(dynamin)依赖途径侵入SH-SY5Y和Vero细胞,但不通过小窝蛋白依赖途径入胞。这些结果为进一步研究狂犬病病毒感染机制和药物靶点研究提供了新的数据。 展开更多
关键词 狂犬病病毒 入胞途径 抑制剂 网格蛋白 低PH值 DYNAMIN 小窝蛋白
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聚乙二醇可提高包被抗原的稳定性 被引量:1
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作者 宋颖 李莹莹 +5 位作者 任严新 陈云云 waqas ahmad 段铭 关振宏 张茂林 《黑龙江畜牧兽医》 CAS 北大核心 2014年第10期6-9,共4页
为了筛选抗原封闭液中聚乙二醇(PEG4000)的适宜浓度,首先用狂犬病病毒(Rabies virus,RV)细胞培养物包被抗原板,以含1%BSA和5%蔗糖的PBST溶液中加入不同浓度的PEG作为封闭液,分别于4℃、37℃保存7,14,30,90,180 d,从中筛选含适宜浓度PEG... 为了筛选抗原封闭液中聚乙二醇(PEG4000)的适宜浓度,首先用狂犬病病毒(Rabies virus,RV)细胞培养物包被抗原板,以含1%BSA和5%蔗糖的PBST溶液中加入不同浓度的PEG作为封闭液,分别于4℃、37℃保存7,14,30,90,180 d,从中筛选含适宜浓度PEG的封闭液,然后分别用乙肝表面抗原(HBsAg)、猪瘟病毒E2抗原(CSFV E2)和猪繁殖与呼吸综合征nsp2基因(PRRSV nsp2)原核表达产物作为包被抗原,对所筛选出的封闭液进行稳定性评价。结果表明:当封闭液为含12%PEG+1%BSA+5%蔗糖的PBST时,上述4种抗原包被板均可在37℃稳定保存180 d。由于该封闭液对不同来源抗原所具有的良好稳定性,初步推断该封闭液可能具有较广泛的应用前景。 展开更多
关键词 聚乙二醇(PEG) 包被抗原 狂犬病毒(RV) 封闭液 保存稳定性
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Rabies virus co-localizes with early(Rab5) and late(Rab7) endosomal proteins in neuronal and SH-SY5Y cells 被引量:3
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作者 waqas ahmad Yingying Li +5 位作者 Yidi Guo Xinyu Wang Ming Duan Zhenhong Guan Zengshan Liu Maolin Zhang 《Virologica Sinica》 SCIE CAS CSCD 2017年第3期207-215,共9页
Rabies virus(RABV) is a highly neurotropic virus that follows clathrin-mediated endocytosis and p H-dependent pathway for trafficking and invasion into endothelial cells. Early(Rab5, EEA1) and late(Rab7, LAMP1) endoso... Rabies virus(RABV) is a highly neurotropic virus that follows clathrin-mediated endocytosis and p H-dependent pathway for trafficking and invasion into endothelial cells. Early(Rab5, EEA1) and late(Rab7, LAMP1) endosomal proteins play critical roles in endosomal sorting, maturity and targeting various molecular cargoes, but their precise functions in the early stage of RABV neuronal infection remain elusive. In this study, the relationship between enigmatic entry of RABV with these endosomal proteins into neuronal and SH-SY5 Y cells was investigated.Immunofluorescence, TCID_(50) titers, electron microscopy and western blotting were carried out to determine the molecular interaction of the nucleoprotein(N) of RABV with early or late endosomal proteins in these cell lines. The expression of N was also determined by down-regulating Rab5 and Rab7 in both cell lines through RNA interference. The results were indicative that N proficiently colocalized with Rab5/EEA1 and Rab7/LAMP1 in both cell lines at 24 and 48 h post-infection, while N titers significantly decreased in early infection of RABV. Down-regulation of Rab5 and Rab7 did not inhibit N expression, but it prevented productive infection via blocking the normal trafficking of RABV in a low pH environment. Ultrathin sections of cells studied by electron microscope also verified the close association of RABV with Rab5 and Rab7 in neurons. From the data it was concluded that primary entry of RABV strongly correlates with the kinetics of Rab-proteins present on early and late vesicles, which provides helpful clues to explain the early events of RABV in nerve cells. 展开更多
关键词 狂犬病病毒 神经细胞 早期阶段 胞内蛋白 神经元 晚期 共定位 分子相互作用
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