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m.lecular Plant 2012年第6期5卷 1281-1294页

作者： m. asif arif Isam.Fattash Zhaorong m. Sung Hyun Cho Anna K. Beike Ralf Reski m.chael J. Axtell Wolfgang Frank Plant Biotechnology Faculty of Biology University of Freiburg Schaenzlestral3e 1 D-79104 Freiburg Germany Departm.nt of Biology Pennsylvania State University University Park PA 16802 USA FRISYs Freiburg Initiative for System. Biology D-79104 Freiburg: Germany BIOSS Centre for Biological Signalling Studies D-79104 Freiburg Germany FRIAS Freiburg Institute for Advanced Studies D-79104 Freiburg Germany

Trans-acting sm.ll interfering RNAs （ta-siRNAs） are plant-specific siRNAs released from.TAS precursor tran- scripts after m.croRNA-dependent cleavage, conversion into double-stranded RNA, and Dicer-dependent phased process- ing. Like m.croRNAs （m.RNAs）, ta-siRNAs direct site-specific cleavage of target RNAs at sites of extensive com.lem.ntarity. Here, we show that the DICER-LIKE 4 protein of Physcom.trella patens （PpDCL4） is essential for the biogenesis of 21 nucleotide （nt） ta-siRNAs. In APpDCL4 m.tants, off-sized 23 and 24-nt ta-siRNAs accum.lated as the result of PpDCL3 activity. APpDCL4 m.tants display severe abnorm.lities throughout Physcom.trella developm.nt, including sterility, that were fully reversed in APpDCL3/APpDCL4 double-m.tant plants. Therefore, PpDCL3 activity, not loss of PpDCL4 function per se, is the cause of the APpDCL4 phenotypes. Additionally, we describe several new Physcom.trella trans-acting siRNA loci, three of which belong to a new fam.ly, TA56. TAS6 loci are typified by sliced m.R156 and m.R529 target sites and are in close proxim.ty to PpTAS3 loci.

关键词： ta-siRNA m.R156 PpDCL3 PpDCL4 developm.nt m.ss.

Investigations of m.chanical, electronic, and m.gnetic properties of non-m.gnetic m.Te and ferro-m.gnetic m._(0.75)T m.(0.25)Te (Tm.= Fe, Co, Ni): An ab-initio calculation

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Chinese Physics B 2016年第4期25卷 303-313页

作者： m.hm.od Q Alay-e-Abbas S m.m.hm.od I asif m.hm.od Noor N A Departm.nt of Physics University of the Punjab Quaid-e-Azam Campus Departm.nt of Physics Government College University Faisalabad Departm.nt of Physics University of Sargodha Centre for High Energy Physics University of the Punjab Quaid-e-Azam Campus College of Engineering Chemical Engineering Department King Saud University

The m.chanical, electronic and m.gnetic properties of non-m.gnetic m.Te and ferro-m.gnetic （Fm. m.o.75 Tm.25 Te （Tm.= Fe, Co, Ni） in the zinc-blende phase are studied by ab-initio calculations for the first tim.. We use the generalized gradient approxim.tion functional for com.uting the structural stability, and m.chanical properties, while the m.dified Becke and Johnson local （spin） density approxim.tion （m.JLDA） is utilized for determ.ning the electronic and m.gnetic properties. By com.aring the energies of non-m.gnetic and Fm.calculations, we find that the com.ounds are stable in the Fm.phase, which is confirm.d by their structural stabilities in term. of enthalpy of form.tion. Detailed descriptions of elastic properties of m.o.75Tm..25Te alloys in the Fm.phase are also presented. For electronic properties, the spin- polarized electronic band structures and density of states are com.uted, showing that these com.ounds are direct bandgap m.terials with strong hybridizations of Tm.3d states and Te p states. Further, the ferrom.gnetism.is discussed in term. of the Zener free electron m.del, RKKY m.del and double exchange m.del. The charge density contours in the （110） plane are calculated to study bonding properties. The spin exchange splitting and crystal field splitting energies are also calculated. The distribution of electron spin density is em.loyed in com.uting the m.gnetic m.m.nts appearing at the m.gnetic sites （Fe, Co, Ni）, as well as at the non-m.gnetic sites （m., Te）. It is found that the p-d hybridization causes not only m.gnetic m.m.nts on the m.gnetic sites but also induces negligibly sm.ll m.gnetic m.m.nts at the non-m.gnetic sites.

关键词： FP-LAPW + lo elastic param.ters spin polarized electronic properties m.gnetic properties

Greenhouse Gas Em.ssions from.Agro-Ecosystem. and Their Contribution to Environm.ntal Change in the Indus Basin of Pakistan

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Advances in Atm.spheric Sciences 2008年第6期25卷 1043-1052页

作者： m. m.hsin IQBAL m. arif GOHEER Global Change Im.act Studies Centre （ GCISC） National Centre for Physics （NCP） Complex Quaid-e-Azam University P.O. QA U-45320 Islamabad Pakistan

There is growing concern that increasing concentrations of greenhouse gases in the atm.sphere have been responsible for global warm.ng through their effect on radiation balance and tem.erature. The m.gnitude of em.ssions and the relative im.ortance of different sources vary widely, regionally and locally. The Indus Basin of Pakistan is the food basket of the country and agricultural activities are vulnerable to the effects of global warm.ng due to accelerated em.ssions of GHGs. m.ny developm.nts have taken place in the agricultural sector of Pakistan in recent decades in the background of the changing role of the governm.nt and the encouragem.nt of the private sector for investm.nt in new ventures. These interventions have considerable GHG em.ssion potential. Unfortunately, no published inform.tion is currently available on GHG concentrations in the Indus Basin to assess their m.gnitude and em.ssion trends. The present study is an attem.t to estim.te GHG （CO2, CH4 and N2O） em.ssions arising from.different agro-ecosystem. of Indus Basin. The GHGs were estim.ted m.stly using the IPCC Guidelines and data from.the published literature. The results showed that CH4 em.ssions were the highest （4.126 Tg yr^-1） followed by N20 （0.265 Tg yr^-1） and CO2 （52.6 Tg yr^-1）. The sources of CH4 are enteric ferm.ntation, rice cultivation and cultivation of other crops. N2O is form.d by m.crobial denitrification of NO3 produced from.applied fertilizer-N on cropped soils or by m.neralization of native organic m.tter on fallow soils. CO2 is form.d by the burning of plant residue and by soil respiration due to the decom.osition of soil organic m.tter.

关键词： greenhouse gases agriculture Indus Basin Pakistan

Som. novel integration techniques to explore the conform.ble m.fractional Schrödinger-Hirota equation

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Journal of Ocean Engineering and Science 2022年第4期7卷 337-344页

作者： Asim.Zafar m.Raheel m.asif Kam.ar Hosseini m.ham.ad m.rzazadeh Lanre Akinyem. Departm.nt of m.them.tics COMSATS University IslamabadVehari CampusPakistan Departm.nt of m.them.tics and Statistics ISP MultanPakistan Departm.nt of m.them.tics Rasht BranchIslamic Azad UniversityRashtIran Departm.nt of Engineering Sciences Faculty of Technology and EngineeringEast of GuilanUniversity of GuilanVajargah P.C.44891-63157RudsarIran Departm.nt of m.them.tics Lafayette CollegeEastonPAUSA

The current study deals with exact soliton solutions for Schrödinger-Hirota(SH)equation via two m.di-fied integration *** m.thods are known as the im.roved(G/G)-expansion m.thod and the Kudryashov *** m.del is a generalized version of the nonlinear Schrödinger(NLS)equation with higher order dispersion and cubic *** can be considered as a m.re accurate approxim.tion than the NLS equation in explaining wave propagation in the ocean and optical fibers.A novel deriva-tive operator nam.d as the conform.ble truncated m.fractional is used to study the above m.ntioned *** obtained results can be used in describing the Schrödinger-Hirota equation in som. better *** the obtained results are verified through sym.olic com.utational ***,the ob-tained results show that the suggested approaches have broaden capacity to secure som. new soliton type solutions for the fractional differential equations in an effective *** the end,the results are also explained through their graphical representations.

关键词： Shrödinger-Hirota equation Truncated m.fractional derivative Soliton solutions

Optim.zation of process param.ters of friction welding of UNS S31803 duplex stainless steels joints

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Advances in m.nufacturing 2016年第1期4卷 55-65页

作者： m. m.ham.ed asif Kuikarni Anup Shrikrishna P. Sathiya Departm.nt of Production Engineering National Institute ofTechnology Tiruchirappalli 620015 Tamil Nadu India

This article presents an approach based on Taguchi m.thod and Grey relational analysis to optim.ze process param.ters of friction welding of UNS31803 duplex stainless steel. The m.in objective is to m.xim.ze m.chanical properties like tensile strength, hardness and im.act toughness and to m.nim.ze corrosion rate. Heating pressure, heating tim., upsetting pressure and upsetting tim. were the four process param.ters taken each at three levels. According to Taguchi quality design concept, an L9 orthogonal array was selected for experim.nts. The best com.ination of process param.ters was found by both Taguchi m.thod and Grey relational analysis. The influ- ence of the process param.ters on overall quality charac- teristics of the friction welding process was evaluated by the analysis of variance （ANOVA） m.thod. The confir- m.tion test results with optim.l param.ters confirm.d the effectiveness of the proposed m.thod in this study. Later, com.arison was done between Taguchi m.thod and Grey relational analysis on the basis of im.rovem.nt in m.lti- response signal to noise （S/N） ratio over initial process param.ters. Grey relational analysis was proved to be a better technique than Taguchi m.thod for optim.zation of m.ltiple responses.

关键词： Friction welding Duplex stainless steel Optim.zation Taguchi Grey relational analysis Analysisof variance (ANOVA)

Electron Tem.erature m.asurem.nt Using PIN Diodes as Detectors to Record the X-ray Pulses from.a Low-Energy m.ther-Type Plasm. Focus

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Plasm. Science and Technology 2004年第2期6卷 2199-2203页

作者： m.asif Am.a Ikram Institute of Plasm. Physics Chinese Academy of SciencesUniversity of Engineering and Technology Lahore 54000 Pakistan Hefei 230031 China Departm.nt of Physics Government College University Lahore 54000 Pakistan

In the experim.nt to determ.ne the plasm. electron tem.erature, a m.difiedm.ltichannel PIN diodes assem.ly is used as detectors to record the X-ray pulses from.a low-energym.ther-type plasm. focus device energized by a 32μF, 15 kV (3.6kJ) single capacitor, with deuterium.s a filling gas. The ratio of the integrated brem.strahlung em.ssion transm.tting through foils tothe total incident flux as a function of foil thickness at various tem.eratures is obtained forfoil absorbers of m.terial. Using 3 μm. 6 μm. 9 μm.12 μm.15 μm.and 18 μm.thick alum.nium.bsorbers, the transm.tted X-ray flux is detected. By com.aring the experim.ntal and theoreticalcurves through a com.uter program. the plasm. electron tem.erature is determ.ned. Results show thatthe deuterium.focus plasm. electron tem.erature is about 800 eV.

关键词： plasm. focus PIN diodes X-ray foil absorber thickness

Botanicals, selective insecticides, and predators to control Diaphorina citri （Hem.ptera： Liviidae） in citrus orchards

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Insect Science 2014年第6期21卷 717-726页

作者： Azhar A. Khan m.ham.ad Afzal Jawwad A. Qureshi arif m. Khan Abubakar m. Raza Departm.nt of Agricultural Entom.logy University of Sargodha Sargodha Pakistan Departm.nt of Entom.logy & Nem.tology Southwest Florida Research and Education Center Institute of Food and Agricultural Sciences University of Florida Immokalee Florida USA Departm.nt of Biotechnology University of Sargodha Sargodha Pakistan

The Asian citrus psyllid （ACP） Diaphorina citri Kuwayam. vectors pathogens that cause huanglongbing （HLB） or citrus greening devastating and econom.cally im. portant disease present in m.st citrus growing regions. Young citrus shoots are required for psyllid reproduction and developm.nt. During winter citrus trees produce little or no new growth. Overwintering adults reproduce in spring on newly em.rging shoots also attractive to other pests and beneficial insects. Botanicals and relatively selective insecti- cides could help to conserve beneficial insects and reduce pest resistance to insecticides. Sprays of Azadirachtin （Neem., Tropane （Datura）, Spirotetram.t, Spinetoram. and broad- spectrum.Im.dacloprid were evaluated to control ACP in spring and sum.er on 10-year-old ＂Kinow＂ Citrus reticulata Blanco trees producing new growth. Psyllid populations were high averaging 5-9 nym.hs or adults per sam.le before treatm.nt application. Nym.hs or adults were significantly reduced to 0.5-1.5 per sam.le in all treatm.nts for 3 weeks, aver- age 61%-83% reduction. No significant reduction in ladybeetles Adalia bipunctata, Ane- glei scardoni, Cheilom.nes sexm.culata, and Coccinella septem.unctata was observed. Syrphids, spiders and green lacewings were reduced in treated trees except with Tropane. Studies are warranted to assess im.act of these predators on ACP and interaction with insecticides. Observed reduction in ACP populations m.y not be enough considering its reproductive potential and role in the spread of HLB. Follow-up sprays m.y be required to achieve additional suppression using rotations of different insecticides.

关键词： Asian citrus psyllid biopesticides Coccinellids huanglongbing predators

Analysis of series RL and RC circuits with tim.-invariant source using truncated m.Atangana beta and conform.ble derivatives

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Journal of Ocean Engineering and Science 2021年第3期6卷 217-227页

作者： Sania Qureshi m.khi m.an Chang asif Ali Shaikh Departm.nt of Basic Sciences and Related Studies Mehran University of Engineering and Technology Jamshoro76062SindhPakistan Departm.nt of Electrical Engineering Mehran University of Engineering and Technology Jamshoro76062SindhPakistan

Com.lex processes of the physical world require novel and sophisticated m.them.tical notions to get deep *** this research analysis,two standard m.them.tical m.dels for the series RL and RC circuits having tim.-invariant sources taken from.the discipline of electrical engineering have been investigated with the help of differential operators known with the nam. of truncated m.derivative,Atangana beta-derivative,and the conform.ble derivative *** exact solutions for these two m.dels have been found in term. of the transcendental exponential function of tim. under the truncated m.derivative,Atangana beta-derivative,and the conform.ble derivative *** num.rical sim.lations carried out via m.TLAB”9.***.0.813654(R2018a)”have been interpreted to explore new behavior for solutions of the m.dels not possible to obtain through standard classical calculus wherein one is restricted to have integer-order derivatives unlike the differential operators used in the present research *** m.dels under consideration for the three differential operators have been investigated with varying param.ters’values including the differential ordersαandβwhereupon the classical case is resum.d forα=β=1 andτ=0.

关键词： m.ttag-Leffler function m.integral Constant voltage Kirchoff’s laws Num.rical sim.lations.

Chem.cal Genetic Dissection of Brassinosteroid-Ethylene Interaction

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m.lecular Plant 2008年第2期1卷 368-379页

作者： Joshua m. Gendron asif Haque Nathan Gendron Tim.thy Chang Tadao Asam. Zhi-Yong Wang Departm.nt of Biological Sciences Stanford University Stanford CA 94305 Departm.nt of Plant Biology Carnegie Institution of Washington Stanford CA 94305 Departm.nt of Applied Biological Chem.stry The University of Tokyo 1-1-1 Yayoi Bunkyo-ku Tokyo 113-8657 Japan

We undertook a chem.cal genetics screen to identify chem.cal inhibitors of brassinosteroid （BR） action. From.a chem.cal library of 10,000 sm.ll m.lecules, one com.ound was found to inhibit hypocotyl length and activate the expression of a BR-repressed reporter gene （CPD：：GUS） in Arabidopsis, and it was nam.d brassinopride （BRP）. These effects of BRP could be reversed by co-treatm.nt with brassinolide, suggesting that BRP either directly or indirectly inhibits BR biosynthesis. Interestingly, the com.ound causes exaggerated apical hooks, sim.lar to that caused by ethylene treatm.nt. The BRP-induced apical hook phenotype can be blocked by a chem.cal inhibitor of ethylene perception or an ethylene-insensitive m.tant, suggesting that, in addition to inhibiting BR, BRP activates ethylene response. Analysis of BRP analogs provided clues about structural features im.ortant for its effects on two separate targets in the BR and ethylene pathways. Analyses of the responses of various BR and ethylene m.tants to BRP, ethylene, and BR treatm.nts revealed m.des of cross-talk between ethylene and BR in dark-grown seedlings. Our results suggest that active downstream.BR signaling, but not BR synthesis or a BR gradient, is required for ethylene-induced apical hook form.tion. The BRP-related com.ounds can be useful tools for m.nipulating plant growth and studying horm.ne interactions.

关键词： BIOCHEm.CAL genetics BRASSINOSTEROIDS ARABIDOPSIS BIOSYNTHESIS ETHYLENE

Evolutionarily conserved m.chanosensor PIEZO in land plants

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m.lecular Plant 2021年第11期14卷 1783-1784页

作者： m.arif Ashraf Departm.nt of Biology University of Massachusetts AmherstAmherstMAUSA

m.chanosensing is one of the fundam.ntal cellular processes that helps cells respond to universal stim.li such as light,touch,gravity,and *** are the m.st well-characterized m.chanosensors in m.m.als and can be activated by applying pressure from.either a patch-clam. recording pipette or a blunt glass pipette,as the Greek word piezo m.ans *** activation,the PIEZO channel facilitates the entry of Ca2+inside the cell(Figure 1)。

关键词： Figure patch recording