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1113篇 您的检索式:作者名="TAHIR"
    题名 作者 年代 出处 被引量
1黄土高原苹果园深层土壤干燥化特征显示文摘为了评价黄土高原苹果产区深层土壤干燥化特征及其区域分布规律,测定了其半湿润黄土台塬区(Ⅰ)、半湿润易旱黄土旱塬区(Ⅱ)、半湿润偏旱和半干旱黄土丘陵区(Ⅲ)等不同气候和地貌类型区32块苹果园地0~1500cm土层土壤湿度,定量比较和分析了各类型区苹果园地深层土壤含水率、土壤湿度剖面分布及其土壤干燥化特征。结果表明:1)Ⅰ、Ⅱ、Ⅲ区苹果园地0~1500cm土层土壤含水率依次为17.53%、13.44%和10.29%,土壤有效贮水量依次为1273.70、973.98和864.05mm,土壤水分过耗量依次为199.93、465.10和362.70mm,年均土壤干燥化速率依次为8.47、26.29和23.44mm/a。人工补灌、树龄、种植密度和地貌类型等因素影响果园土壤湿度和土壤干燥化程度。2)各区有补充灌溉的果园土壤剖面湿度显著高于旱作果园,不存在或部分土层存在干燥化现象;旱作果园土壤剖面均存在深厚的干燥化土层。3)Ⅰ、Ⅱ和Ⅲ区有补充灌溉的苹果园地土壤干燥化指数(SDI)分别为-8%、-11%和-34%;旱作果园土壤干燥化指数(SDI)分别为32%、50%和46%,各类型干层厚度分别达到或超过790、1297和910cm。研究结果为黄土高原苹果园地深层土壤水分可持续利用和苹果生产基地可持续发展提供参考。曹裕 李军 张社红 王亚莉 程科 王学春 王玉玲 M.Naveed Tahir 2012农业工程学报2012,28,15:48
2A scientometric review of biochar research in the past 20 years(1998-2018)显示文摘Biochar is the carbon-rich product obtained from the thermochemical conversion of biomass under oxygen-limited conditions.Biochar has attained extensive attention due to its agronomical and environmental benefits in agro-ecosystems.This work adopts the scientometric analysis method to assess the development trends of biochar research based on the literature data retrieved from the Web of Science over the period of 1998-2018.By analysing the basic characteristics of 6934 publications,we found that the number of publications grew rapidly since 2010.Based on a keyword analysis,it is concluded that scholars have had a fundamental recognition of biochar and preliminarily found that biochar application had agronomic and environmental benefits during the period of 1998-2010.The clustering results of keywords in documents published during 2011-2015 showed that the main research hotspots were“biochar production”,“biochar and global climate change”,“soil quality and plant growth”,“organic pollutants removal”,and“heavy metals immobilization”.While in 2016-2018,beside these five main research hotspots,“biochar and composting”topic had also received greater attention,indicating that biochar utilization in organic solid waste composting is the current research hotspot.Moreover,updated reactors(e.g.,microwave reactor,fixed-bed reactor,screw-feeding reactor,bubbling fluidized bed reactor,etc.)or technologies(e.g.,solar pyrolysis,Thermo-Catalytic Reforming process,liquefaction technology,etc.)applied for efficient energy production and modified biochar for environmental remediation have been extensively studied recently.The findings may help the new researchers to seize the research frontier in the biochar field.Ping Wu Syed Tahir Ata-Ul-Karim Bhupinder Pal Singh Hailong Wang Tongliang Wu Cun Liu Guodong Fang Dongmei Zhou Yujun Wang Wenfu Chen 2019Biochar2019,1,1:36
3Structural basis of SARS-CoV-2 3CL^pro and anti-COVID-19 drug discovery from medicinal plants显示文摘The recent pandemic of coronavirus disease 2019(COVID-19)caused by SARS-CoV-2 has raised global health concerns.The viral 3-chymotrypsin-like cysteine protease(3CL^pro)enzyme controls coronavirus replication and is essential for its life cycle.3CL^pro is a proven drug discovery target in the case of severe acute respiratory syndrome coronavirus(SARS-CoV)and Middle East respiratory syndrome coronavirus(MERS-CoV).Recent studies revealed that the genome sequence of SARS-CoV-2 is very similar to that of SARS-CoV.Therefore,herein,we analysed the 3CL^pro sequence,constructed its 3D homology model,and screened it against a medicinal plant library containing 32,297 potential anti-viral phytochemicals/traditional Chinese medicinal compounds.Our analyses revealed that the top nine hits might serve as potential anti-SARS-CoV-2 lead molecules for further optimisation and drug development process to combat COVID-19.Muhammad Tahir ul Qamar Safar MAlqahtani Mubarak AAlamri Ling-Ling Chen 2020Journal of Pharmaceutical Analysis2020,10,4:29
4阿拉伯胶/白色玫瑰茄提取物复合涂膜对低温贮藏蓝莓保鲜效果的影响显示文摘为改善低温贮藏蓝莓果实易于腐败的问题,探讨一种可以改善蓝莓贮藏品质的保鲜处理方法。实验以‘兔眼’蓝莓品种为试材,在(4.0±0.5)℃、相对湿度75%的贮藏条件下,采用100 mg/mL阿拉伯胶+体积分数1.5%甘油(M1)、100 mg/mL阿拉伯胶+体积分数1.5%甘油+体积分数1.5%白色玫瑰茄提取物(white roselle extract,WRE)(M2)、100 mg/mL阿拉伯胶+体积分数1.5%甘油+体积分数2.5%WRE(M3)3种可食性涂膜液对蓝莓样品进行涂膜处理,通过分析果实理化性质、抗氧化酶活力和抗氧化物质含量等指标的变化,探讨复合涂膜对低温贮藏蓝莓保鲜效果的影响。结果表明:在低温贮藏的条件下,阿拉伯胶复合涂膜可以显著减缓蓝莓果实质量损失、降低腐烂率和延缓硬度降低(P<0.05),并能维持果实较高的总酚、花色苷含量和较好的感官品质,显著抑制多酚氧化酶(polyphenol oxidase,PPO)活力和降低果实表面褐变程度(P<0.05);且M3涂膜剂在抑制低温贮藏蓝莓果实PPO活力、维持果实总酚和花色苷含量、改善感官品质方面具有最佳效果。综合分析各项指标可得出,M3涂膜剂对低温贮藏蓝莓的保鲜效果最好。邹小波 杨志坤 石吉勇 黄晓玮 张文 Haroon Elrasheid TAHIR 2019食品科学2019,40,7:23
5夏玉米叶片全氮含量高光谱遥感估算模型研究显示文摘在5种不同施氮量和2种夏玉米品种处理下,分别在玉米拔节期、大喇叭口期、抽雄期、吐丝期、乳熟期测定了玉米冠层高光谱反射率及其对应叶片的全氮含量。选取了470、550、620和720 nm 4个代表性光谱波段,分品种对叶片全氮含量与原始光谱反射率、光谱反射率一阶微分以及部分高光谱特征参数(基于光谱位置、面积、植被指数的特征参量)分别进行线性回归和非线性回归拟合。在每个生育时期,选择决定系数和F值最高的模型3个,并分别用第二年测定的光谱和全氮含量数据分别对两个品种进行均方根差和相对误差的验证,选择均方根差和相对误差较小的拟合模型。结果表明,在拔节期、大喇叭口期、抽雄期、吐丝期和乳熟期,玉米叶片全氮含量最佳拟合光谱参量分别为R720、DR720、SDb、DR550和DR550,玉米叶片全氮含量最佳高光谱遥感估算模型依次为Y=5.129e-2.317x、Y=3.421-10.010x-477802.331x3、Y=4.070-2.304x-52.177x2、Y=-0.468-0.528lnx和Y=-2.390-0.793lnx。刘冰峰 李军 赵刚峰 Naveed Tahir 贺佳 2012植物营养与肥料学报2012,18,4:18
6Endoscopic pancreatic sphincterotomy:indications,outcome,and a safe stentless technique显示文摘Endoscopicpancreaticsphincterotomy:indications,outcome,andasafestentlesstechniquericElton,MD,DouglasA.Howel,MD,WilisG.Parsons...Eric Elton, MD, Douglas A. Howell, MD, Willis G. Parsons, MD, Tahir Qaseem, MD, Brian L. Hanson, MDPortland, MaineDivision of Gastroenterology, Maine Medical Center, Portland, Maine 1998World Journal of Gastroenterology1998,4,3:16
7Liquid Phase Bonding of 316L Stainless Steel to AZ31 Magnesium Alloy显示文摘The excellent corrosion resistance,formability and strength make stainless steels versatile for diverse applications.However,its high specific strength and good crashworthiness make it suitable for transportation and aerospace industry.On the other hand,the need to reduce the weight of vehicle and aerospace components has created renewed interest in the use of magnesium alloys.Due to their differences in physical and metallurgical properties,bonding of the 316L steel and AZ31 magnesium alloy using conventional fusion welding methods encountered many limitations.Therefore,the use of liquid phase forming interlayers is required to overcome the differences in their properties,eliminates the need for a high bonding pressure to achieve intimate contact between the bonded surfaces.Both Cu and Ni interlayers successively formed a eutectic phase with magnesium.The formation of intermetallics and Mg diffusion caused the eutectic phase to isothermally solidify with increasing bonding time.The formation of ternary intermetallic phases(λ1 and B2) impaired the bond shear strength particularly at the end of the isothermal solidification stage where no eutectic phase was observed.However,the joints showed a higher shear strength value of 57 MPa when bonding with Cu interlayer at 530℃ for 30 min compared to 32 MPa when Ni interlayer was used at 510℃ for 20 min.Waled Elthalabawy Tahir Khan 2011Journal of Materials Science & Technology2011,27,1:14
8Retrospective study on mixed neuroendocrine non-neuroendocrine neoplasms from five European centres显示文摘BACKGROUND Mixed neuroendocrine non-neuroendocrine neoplasm(MiNEN)is a rare diagnosis,mainly encountered in the gastro-entero-pancreatic tract.There is limited knowledge of its epidemiology,prognosis and biology,and the best management for affected patients is still to be defined.AIM To investigate clinical-pathological characteristics,treatment modalities and survival outcomes of a retrospective cohort of patients with a diagnosis of MiNEN.METHODS Consecutive patients with a histologically proven diagnosis of MiNEN were identified at 5 European centres.Patient data were retrospectively collected from medical records.Pathological samples were reviewed to ascertain compliance with the 2017 World Health Organisation definition of MiNEN.Tumour responses to systemic treatment were assessed according to the Response Evaluation Criteria in Solid Tumours 1.1.Kaplan-Meier analysis was applied to estimate survival outcomes.Associations between clinical-pathological characteristics and survival outcomes were explored using Log-rank test for equality of survivors functions(univariate)and Cox-regression analysis(multivariable).RESULTS Sixty-nine consecutive patients identified;Median age at diagnosis:64 years.Males:63.8%.Localised disease(curable):53.6%.Commonest sites of origin:colon-rectum(43.5%)and oesophagus/oesophagogastric junction(15.9%).The neuroendocrine component was;predominant in 58.6%,poorly differentiated in 86.3%,and large cell in 81.25%,of cases analysed.Most distant metastases analysed(73.4%)were occupied only by a poorly differentiated neuroendocrine component.Ninety-four percent of patients with localised disease underwent curative surgery;53%also received perioperative treatment,most often in line with protocols for adenocarcinomas from the same sites of origin.Chemotherapy was offered to most patients(68.1%)with advanced disease,and followed protocols for pure neuroendocrine carcinomas or adenocarcinomas in equal proportion.In localised cases,median recurrence free survival(RFS);14.0 months(95%CI:9.2-24.4),and median overall survival(OS):28.6 months(95%CI:18.3-41.1).On univariate analysis,receipt of perioperative treatment(vs surgery alone)did not improve RFS(P=0.375),or OS(P=0.240).In advanced cases,median progression free survival(PFS);5.6 months(95%CI:4.4-7.4),and median OS;9.0 months(95%CI:5.2-13.4).On univariate analysis,receipt of palliative active treatment(vs best supportive care)prolonged PFS and OS(both,P<0.001).CONCLUSION MiNEN is most commonly driven by a poorly differentiated neuroendocrine component,and has poor prognosis.Advances in its biological understanding are needed to identify effective treatments and improve patient outcomes.Melissa Frizziero Xin Wang Bipasha Chakrabarty Alexa Childs Tu V Luong Thomas Walter Mohid S Khan Meleri Morgan Adam Christian Mona Elshafie Tahir Shah Annamaria Minicozzi Wasat Mansoor Tim Meyer Angela Lamarca Richard A Hubner Juan W Valle Mairéad G McNamara 2019World Journal of Gastroenterology2019,25,39:13
9Biochar for Sustainable Soil Health:A Review of Prospects and Concerns显示文摘Biochar as a soil amendment is confronted with the challenge that it must benefit soil health as it can be by no means separated from soils once it is added. The available literature even though sparse and mostly based on short-term studies has been encouraging and the trend obtained so far has raised many hopes. Biochar has been reported to positively impact an array of soil processes ranging from benefiting soil biology, controlling soil-borne pathogens, enhancing nitrogen fixation, improving soil physical and chemical properties,decreasing nitrate(NO-3) leaching and nitrous oxide(N2O) emission to remediation of contaminated soils. However, very little biochar is still utilized as soil amendment mainly because these benefits are yet to be quantified, and also the mechanisms by which the soil health is improved are poorly understood. Due to the infancy of research regarding this subject, there are still more questions than answers. The future research efforts must focus on carrying out long-term experiments and uncover the mechanisms underlying these processes so that key concerns surrounding the use of biochar are addressed before its large scale application is recommended.Aabid H.LONE Ghulam R.NAJAR Mumtaz A.GANIE Javid A.SOFI Tahir ALI 2015Pedosphere2015,25,5:12
10稻壳和麦麸对鲜玉米秸秆青贮品质的影响显示文摘为更好地利用稻壳和麦麸,本试验将2者与新鲜玉米(Zea mays L.)秸秆按不同比例混合青贮,发酵60天后测定其青贮品质和营养成分,以期筛选出混贮的最佳比例。结果表明,与鲜玉米秸秆单独青贮(对照)相比,麦麸和鲜玉米秸秆混合青贮的干物质、可溶性碳水化合物和粗蛋白含量均显著提高(P<0.05),但丁酸含量超过1%,发酵品质较差;与对照相比,稻壳与鲜玉米秸秆混合青贮的粗蛋白、可溶性碳水化合物含量和氨态氮/总氮的值均显著下降(P<0.05);稻壳、麦麸与鲜玉米秸秆混合青贮的发酵品质与对照相当,但干物质含量显著提高(P<0.05),且M1F1(5%麦麸+10%稻壳+85%鲜玉米秸秆)处理的Kaiser法评分最高。因此,建议将麦麸、稻壳和鲜玉米秸秆按5∶10∶85的鲜重比混合青贮。杜昭昌 王红 闫艳红 Muhammad Tahir 韦潇 曾泰儒 李洪亮 2021草地学报2021,29,7:12
11苹果赤霉素信号转导因子MdGAMYB的克隆和表达分析显示文摘以‘长富2号’苹果为试验材料,从其短枝顶芽中克隆得到1个赤霉素信号转导因子MdGAMYB,对其进行生物信息学和表达分析。结果表明,MdGAMYB的开放阅读框(ORF)长度为1 656bp,编码551个氨基酸,蛋白质分子量为59.741 kD。生物信息学分析表明MdGAMYB编码的蛋白存在多个糖基化位点和磷酸化位点;序列分析表明,Md GAYMB和其他物种的GAMYB蛋白有很高的相似性,均含有保守的R2R3 DNA结合域和GAMYB家族所特有的Box1,Box2和Box3保守区域;系统进化分析表明,Md GAYMB与梨、梅花、草莓、枣和葡萄等的GAMYB蛋白具有较高的同源性。实时荧光定量PCR分析表明,Md GAYMB具有组织表达特异性,在叶片、花和芽中的表达量较高。外源GA3处理抑制了花芽孕育和翌年成花,抑制MdGAMYB的表达。在易成花品种‘烟富6号’中的表达量高于难成花品种‘长富2号’。樊胜 雷超 辛明志 邵红霞 Muhammad Mobeen Tahir 张东 韩明玉 2017园艺学报2017,44,5:11
12Ibrutinib alleviated LPS-induced neuroinflam⁃mation and synaptic defects in mouse model of depression显示文摘OBJECTIVE Previous studies have demonstrated a close association between an altered immune system and major depressive disorders,and inhibition of neuroinflammation may represent an alternative mechanism to treat depression.Recently,the anti-inflammatory activ⁃ity of ibrutinib has been reported.However,the effect of ibrutinib on neuroinflammation-induced depression and its underlying mechanism has not been comprehensively studied.Therefore,we aimed to elucidate the potential anti-depres⁃sive role and mechanism of ibrutinib against neu⁃roinflammation-induced depression and synaptic defects.METHODS AND RESULTS Ibrutinib treatment significantly reduced lipopolysaccha⁃ride(LPS)-induced depressive-like behaviors and neuroinflammation via inhibiting NF-κB acti⁃vation,decreasing proinflammatory cytokine levels,and normalizing redox signaling and its downstream components,including Nrf2,HO-1,and SOD2,as well as glial cell activation mark⁃ers,such as Iba-1 and GFAP.Further,ibrutinib treatment inhibited LPS-activated inflammasome activation by targeting NLRP3/P38/caspase-1 signaling.Interestingly,LPS reduced the number of dendritic spines and expression of BDNF,and synaptic-related markers,including PSD95,snap25,and synaptophysin,were improved by ibrutinib treatment in the hippocampal area of the mouse brain.CONCLUSION Ibrutinib can allevi⁃ate neuroinflammation and synaptic defects,sug⁃gesting it has antidepressant potential against LPS-induced neuroinflammation and depression.LI Wei-fen Tahir Ali HE Kai-wu LIU Zi-zhen Fawad Ali Shah REN Qing-guo LIU Yan JIANG An-long LI Shu-peng 2021中国药理学与毒理学杂志2021,35,9:10
13黄土高原半干旱偏旱区草粮轮作田土壤水分恢复效应模拟显示文摘采用实地调查和EPIC模型相结合的方法,模拟研究了黄土高原半干旱偏旱区不同草粮轮作模式的土壤水分恢复效应.结果表明:多年生苜蓿地和苜蓿翻耕后种植粮食作物农田0~10m土层土壤湿度调查值与模拟值间的相关系数均超过0.9(P<0.01),相对均方根误差在0.05~0.16,相对误差均低于10%;模拟与实测的土壤湿度剖面分布变化趋势一致.在黄土高原半干旱偏旱区,苜蓿地深层土壤干层恢复难度较大,在种植苜蓿期间应避免8~10m土层土壤湿度降到5.7%以下.苜蓿地适宜种植年限为4~6a,最长不应超过8a.苜蓿翻耕后适宜采用马铃薯→马铃薯→春小麦轮作模式进行土壤水分恢复,32~33a后可以再次种植苜蓿.王学春 李军 方新宇 孙剑 Muhammad Naveed Tahir 2011应用生态学报2011,22,1:8
14Psychophysiological Effects of Bamboo Plants on Adults显示文摘The present study was conducted to clarify the psychophysiological relaxation effects of viewing bamboo on university students. Forty healthy Chinese participants enrolled in this study to clarify the psychophysiological relaxation effects of viewing bamboo. The effects of visual stimulation using a pot both with and without a bamboo were recorded by measuring the student's blood pressure, EEG and STAI. We observed that viewing bamboo plants resulted in significantly lower systolic(female, P < 0.001; male, P < 0.001; P < 0.05) and diastolic(female,P < 0.001; male, P < 0.001; P < 0.05) blood pressures, but no changes in the pulse rate(female, P = 0.09; male, P = 0.07; P > 0.05) were observed. The results of the EEG analysis indicated brainwave variation(all P < 0.05) and lower anxiety scores(P < 0.01) after 3 min of viewing bamboo compared with the control. These findings indicate that visual stimulation with bamboo plants induced psychophysiological relaxation effects on adults.Ahmad Hassan CHEN Qi Bing JIANG Tao LYU Bing Yang LI Nian LI Shu SHANGGUAN Zi Yue LI Yun Ting JUN Zhou Li LUO Qian CHEN Xin Yi WANG Yi Yan ZENG Cheng Cheng YANG Jun Muhammad Sohaib Tahir 2017Biomedical and Environmental Sciences2017,30,11:8
15茶多酚热解特性及其反应机理研究显示文摘以红茶茶多酚和绿茶茶多酚为原料,利用同步热分析(TGA/DSC)、红外光谱分析(FT-IR)和质谱分析(MS)联用技术观测其热解过程中质量变化及产生的气相产物,同时对不同热处理温度下固相残留物的化学组成进行表征,分析茶多酚热解反应机理。结果表明:茶多酚为富含侧链结构的芳香族化合物,主要由C、H、O和微量N元素构成。温度低于200℃时,茶多酚的热失重基本源于所含自由水和结合水的蒸发;热解反应起于200℃附近,取决于其侧链结构的稳定性;在200~350℃间发生剧烈热分解反应,侧链结构出现断裂和重组,生成H2O和CO2为主的气相产物;在350~800℃温度区间,热解反应变得缓慢而持久,反映了残留物向稳定的稠环芳烃结构转变的机制。建立起的认识为茶多酚有效利用和开拓防火领域应用前景提供指南。姚奉奇 陶骏骏 王海晖 胡国庆 陈帅 TAHIR Mudassir Hussian 2017林产化学与工业2017,37,5:8
16Carcinogenesis on the background of liver fibrosis: Implications for the management of hepatocellular cancer显示文摘Hepatocellular carcinoma(HCC) is now the second leading cause of cancer-related deaths globally and many patients have incurable disease. HCC predominantly occurs in the setting of liver cirrhosis and is a paradigm for inflammation-induced cancer. The causes of chronic liver disease promote the development of transformed or premalignant hepatocytes and predisposes to the development of HCC. For HCC to grow and progress it is now clear that it requires an immunosuppressive niche within the fibrogenic microenvironment of cirrhosis. The rationale for targeting this immunosuppression is supported by responses seen in recent trials with checkpoint inhibitors. With the impact of immunotherapy, HCC progression may be delayed and long term durable responses may be seen. This makes the management of the underlying liver cirrhosis in HCC even more crucial as studies demonstrate that measures of liver function are a major prognostic factor in HCC. In this review, we discuss the development of cancer in the setting of liver inflammation and fibrosis, reviewing the microenvironment that leads to this tumourigenic climate and the implications this has for patient management.Joanne Marie O'Rourke Vandana Mridhu Sagar Tahir Shah Shishir Shetty 2018World Journal of Gastroenterology2018,24,39:8
17Transfer of Heavy Metals from Soils to Vegetables and Associated Human Health Risks at Selected Sites in Pakistan显示文摘Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper(Cu),zinc(Zn), chromium(Cr), nickel(Ni), and manganese(Mn) in agricultural soils and food crops(fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn > Zn > Cr > Ni > Cu.The bioaccumulation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu > Ni > Cr > Mn >Zn, while the calculated daily intake of metals(DIM) in adults and children through consumption of food crops was in the decreasing order of Mn > Zn > Ni > Cr > Cu. The health risk index(HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops.Zahir Ur REHMAN Sardar KHAN Mohammad Tahir SHAH Mark L.BRUSSEAU Said Akbar KHAN Jon MAINHAGU 2018Pedosphere2018,28,4:7
18Nonlinear joint PP-PS AVO inversion based on improved Bayesian inference and LSSVM显示文摘Multiwave seismic technology promotes the application of joint PP–PS amplitude versus offset (AVO) inversion;however conventional joint PP–PS AVO inversioan is linear based on approximations of the Zoeppritz equations for multiple iterations. Therefore the inversion results of P-wave, S-wave velocity and density exhibit low precision in the faroffset;thus, the joint PP–PS AVO inversion is nonlinear. Herein, we propose a nonlinear joint inversion method based on exact Zoeppritz equations that combines improved Bayesian inference and a least squares support vector machine (LSSVM) to solve the nonlinear inversion problem. The initial parameters of Bayesian inference are optimized via particle swarm optimization (PSO). In improved Bayesian inference, the optimal parameter of the LSSVM is obtained by maximizing the posterior probability of the hyperparameters, thus improving the learning and generalization abilities of LSSVM. Then, an optimal nonlinear LSSVM model that defi nes the relationship between seismic refl ection amplitude and elastic parameters is established to improve the precision of the joint PP–PS AVO inversion. Further, the nonlinear problem of joint inversion can be solved through a single training of the nonlinear inversion model. The results of the synthetic data suggest that the precision of the estimated parameters is higher than that obtained via Bayesian linear inversion with PP-wave data and via approximations of the Zoeppritz equations. In addition, results using synthetic data with added noise show that the proposed method has superior anti-noising properties. Real-world application shows the feasibility and superiority of the proposed method, as compared with Bayesian linear inversion.Xie Wei Wang Yan-Chun Liu Xue-Qing Bi Chen-Chen Zhang Feng-Qi Fang Yuan Tahir Azeem 2019Applied Geophysics2019,16,1:7
19国外农业航空静电喷雾技术研究进展与借鉴显示文摘农业航空静电喷雾技术作为中国发展精准农业航空应用技术的内容之一,对农药的有效利用和减少环境污染有积极意义。农业航空静电喷雾技术在国外发展较早也相对成熟,美国已有应用于有人机的商业化产品,并在美国、巴西等国各类粮食作物、经济作物和杂草防治作业中开展了大规模田间应用。该研究首先从基础研究、田间应用和优化工作等方面梳理了国外农业航空静电喷雾技术的研究进展,分析了农业航空静电喷雾技术在增加雾滴沉积、减少飘移和具备低施药液量等方面的优势。在此基础上结合中国植保无人机快速发展的实际对研究和应用适合中国国情的农业航空静电喷雾技术进行思考,提出了农业航空静电喷雾技术的研究路线,最后从采用接触式等非感应式充电方式、开发农业航空静电喷雾的测量技术,以及思考荷质比作为衡量指标的意义等方面探讨了可进行深入研究的方向。中国农业航空静电喷雾技术研究特别在植保无人机静电喷雾技术方面的研究与应用有很大的发展空间,可参考国外经验,围绕航空静电喷雾技术的基础性研究、田间试验、成果转化、示范推广和服务指导全方面制定发展规划,把单一强调对雾滴带电的实现转向对技术系统的整体研究。张亚莉 黄鑫荣 王林琳 邓继忠 曾文 兰玉彬 Muhammad Naveed Tahir 2021农业工程学报2021,37,6:7
20自噬相关蛋白激酶的研究进展显示文摘自噬是细胞在应激过程中为了维持细胞稳态进行自我降解的过程,适度的细胞自噬有利于细胞生存,但是自噬水平过高或过低都会导致细胞内稳态失衡,甚至细胞死亡,且自噬水平变化与癌症等多种疾病相关.激酶在自噬调控通路中必不可少,近年来对于自噬的研究越来越深入,关于调节自噬进程的蛋白激酶研究也更加全面,有些蛋白激酶直接作为自噬核心蛋白发挥作用,比如unc-51样自噬激活蛋白激酶1(ULK1)/自噬相关蛋白1(Atg1)和Ⅲ类磷脂酰肌醇3-激酶(PI3K),还有些蛋白通过磷酸化自噬核心蛋白对自噬进行调控,比如雷帕霉素靶点蛋白(TOR)、AMP激活蛋白激酶(AMPK)、蛋白激酶C(PKC)、丝裂原活化蛋白激酶(MAPK).以细胞自噬为基础,对蛋白激酶,TOR,ULK1/Atg1,MAPK,PI3K,AMPK和PKC的研究现状进行了综述.宋嘉宁 MUHAMMAD Tahir 张文婷 王娟 2021河北师范大学学报(自然科学版)2021,45,6:7
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