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应用微机的地下水资源数据库管理系统

河海大学科技情报 1990年第3期10卷 125-129页

作者： H.u.khan s.m.khan T.Husain 王海曙

为了有效地管理水资源信息,70年代期间已经大规模使用了计算机系统。在沙特阿拉伯王国水利农业部,水资源开发部门已完成这样一个系统来管理水资源信息。这些信息是通过系统的各种功能而获得的。80年代微机的出现,提供了进一步改善数据... 详细信息

为了有效地管理水资源信息,70年代期间已经大规模使用了计算机系统。在沙特阿拉伯王国水利农业部,水资源开发部门已完成这样一个系统来管理水资源信息。这些信息是通过系统的各种功能而获得的。80年代微机的出现,提供了进一步改善数据采集能力和质量的条件。该数据库包括一些指令和数据库文件。

关键词：微机地下水资源数据库管理

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计算机在增压器设计、研制和试验中的作用

柴油机 1983年第4期 15-30页

作者： m. s. khan P. J. Langdon 聂长庚

增压器压气机叶轮的设计过程是循环递归过程,它包含着画出最后设计图形前在空气动力学和应力分析中多次的迭代步骤。本文讨论了在这两项分析间传递信息的接口,由于在全过程中采用了交互式图象显示技术,因此把设计师从冗长的数据准备中... 详细信息

增压器压气机叶轮的设计过程是循环递归过程,它包含着画出最后设计图形前在空气动力学和应力分析中多次的迭代步骤。本文讨论了在这两项分析间传递信息的接口,由于在全过程中采用了交互式图象显示技术,因此把设计师从冗长的数据准备中解放出来。这种交互式图象技术已扩大应用于加工铸模和样件时构成数据刀具轨迹,且使设计过程中建立的数据库也可用于铸件检查。最后,也可用在试验室进行实时数据采集,并把这些最新的经验数据提供给设计过程。

关键词：数据库空气动力学应力分析轮盖型线数据库系统流体动力学结构分析压缩机级压气机级叶轮出口计算机

感染西葫芦的帕兰波番茄曲叶病毒检测与鉴定(英文)

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广西农业科学 2010年第12期41卷 1291-1295页

作者： A K Tiwari s mall m s khan s K snehi P K sharma s K Rajt G P Rao Kunraghat甘蔗试验站印度戈勒克布尔273008 生物技术园印度勒克瑙226021 国家植物研究所病毒学研究室印度勒克瑙226001 Chaudhary Charan singh大学微生物学研究室印度密鲁特250004

2008年对印度北方邦东部Gorakhpur、Kushinagar与maharajganj等3个地区的西葫芦种植区进行调查,发现西葫芦叶片呈现花叶斑点状、卷曲,植株黄化萎缩。以菜豆金色花叶病毒组外壳蛋白基因特异引物AV1-F、AV1-R对从不同地区收集的西葫芦病... 详细信息

2008年对印度北方邦东部Gorakhpur、Kushinagar与maharajganj等3个地区的西葫芦种植区进行调查,发现西葫芦叶片呈现花叶斑点状、卷曲,植株黄化萎缩。以菜豆金色花叶病毒组外壳蛋白基因特异引物AV1-F、AV1-R对从不同地区收集的西葫芦病斑叶片样品进行PCR分析,获得约800 bp的扩增产物。对从Gorakhpur地区获得的分离物的扩增产物进行克隆和序列分析,测序结果提交GenBank核酸序列数据库;通过核酸BLAsT比对和系统发育分析,该分离物与帕兰波番茄曲叶病毒株的同源性最高,达95%,两者遗传关系最近,认为此病毒分离物是帕兰波番茄曲叶病毒株。

关键词：西葫芦聚合酶链反应系统发育分析帕兰波番茄曲叶病毒

Predicting maximum Lifespan Limits at mean menopausal Age

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Journal of mathematical Research with Applications 2025年第1期 133-142页

作者： m.sUmATHI s.ANTONY CARLA Department of mathematics N.M.S.S.Vellaichamy Nadar College Research scholar (Part-time) Madurai Kamaraj University

The age at which a woman enters natural menopause has also been associated to death from any cause. menopause is a natural component of aging that happens between the ages of 45 and 55, with the average menopausal age being 51. Previous research has revealed the age at which women reach menopause, but there is no evidence to support the link between menopause and longevity. We made a study in assessing the limits of maximum lifespan at menopausal age in our previous article. In this paper, we aim to predict the maximum lifespan of women at mean menopausal age.

关键词：

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa m.G.Cassiano Roney s.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNs)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： s U khan m K A Rahim Advanced RF & microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（mPT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of Hankel matrix（Hm） and execute the singular value decomposition（sVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of Hm. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： s U khan m L Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China University of Chinese Academy of sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Lead and Cadmium Contamination of Different Roadside soils and Plants in Peshawar City, Pakistan

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Pedosphere 2011年第3期21卷 351-357页

作者： s.khan m.A.khan s.REHmAN Department of Environmental sciences University of Peshawar

soil and plant samples were collected from roadside sites (along with primary, secondary and tertiary roads) and reference site to investigate the contamination of soils and old common plant species with lead (Pb) and cadmium (Cd) in Peshawar City, Pakistan. All the data were analyzed using ANOVA analysis that showed a significant (P ≤ 0.01) variation in Pb and Cd concentrations in the roadside soils and plants as compared to the reference site. The mean concentrations of Pb and Cd were 53.9 and 6.0 mg kg-1 in soils and 49.1 and 10.9 mg kg-1 in plants, respectively. significant variation (P ≤ 0.01) in concentrations of Pb and Cd in soil and plant samples along with primary, secondary and tertiary roads might be due to different traffic densities. The highest value (9.4) of metal accumulation index (mAI) was observed for Eucalyptus camaldulensis. In selected plant species, the Pb and Cd accumulation was found in the order of E. camaldulensis > Ficus elastica > Dalbergia sissoo > Alstonia scholaris. The roadside soils and plants were highly contaminated with Pb and Cd as compared to the reference site.

关键词： electrical conductivity heavy metals metal accumulation index tramc density

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-mañé Laia Just-Borràs marta Balanyà-segura Aleksandra Polishchuk Laura Nadal marta Tomàs Carolina silvera-simón manel m.santafé maria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB