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Perspectives of Using L-Tryptophan for Improving Productivity of Agricultural Crops: A Review

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Pedosphere 2018年第1期28卷 16-34页

作者： Ayesha MUSTAFA Muhammad IMRAN Muhammad ASHRAF khalid MAHMOOD Soil and Environmental Sciences Division Nuclear Institute for Agriculture and Biology (NIAB)

Plant growth regulators are biologically active signaling molecules that regulate a number of plant physiological processes. Auxin(indole-3-acetic acid) is an important plant growth regulator and is synthesized within plant tissues through L-tryptophan(L-TRP)-dependent and-independent pathways. It has been found that plants respond to exogenously applied L-TRP due to insufficient endogenous auxin biosynthesis. The exogenous application of L-TRP is highly significant for normal plant growth and development.L-tryptophan is applied through foliar spray, seed priming, and soil application. Soil-applied L-TRP is either directly taken up by plants or metabolized to auxin by soil microbiota and then absorbed by plant roots. Similarly, foliar spray and seed priming with L-TRP stimulates auxin synthesis within plants and improves the growth and productivity of agricultural crops. Furthermore, L-TRP contains approximately 14% nitrogen(N) in its composition, which is released upon its metabolism within a plant or in the rhizosphere and plays a role in enhancing crop productivity. This review deals with assessing crop responses under the exogenous application of L-TRP in normal and stressed environments, mode of action of L-TRP, advantages of using L-TRP over other auxin precursors, and role of the simultaneous use of L-TRP and auxin-producing microbes in improving the productivity of agricultural crops. To the best of our knowledge, this is the first review reporting the importance of the use of L-TRP in agriculture.

关键词： auxin biosynthesis auxin precursors auxin-producing microbes crop productivity indole-3-acetic acid plant growth-promoting rhizobacteria plant response to abiotic stresses

Non-Thermal Effects on CO-NO Surface Catalytic Reaction on Square Surface： Monte Carlo Study

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Chinese Physics Letters 2005年第6期22卷 1533-1535页

作者： M.khalid A.U.Qaisrani W.Ahmad DepartmentofPhysics GomalUniversityDeraIsmailKhanPakistan PhysicsResearchDivision PakistanInstituteofNuclearScienceandTechnologyPONiloreIslamabadPakistan

A Monte Carlo simulation of the CO–NO heterogeneous catalytic reaction over a square surface has already been studied with a model based on the Langmuir–Hinshelwood (LH) mechanism. The results of this study are well known. Here we study the effects of transient non-thermal mobility of monomer (CO) based on precursor mechanism, diffusion of adsorbed nitrogen and oxygen atoms, on the phase diagram. The interesting feature of this model is the yield of a steady reactive window, while simple LH mechanism is not capable of producing a steady reactive state.

关键词： FOPT SOPT CO ZGB

Effect of rare earth and transition metal La-Mn substitution on electrical properties of co-precipitated M-type Ba-ferrites nanoparticles

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Journal of Rare Earths 2019年第2期37卷 193-197页

作者： Muhammad Ayub Iftikhar Hussain Gul khalid Nawaz Khurram Yaqoob Thermal Transport Laboratory School of Chemical and Materials Engineering (SCME) National University of Sciences and Technology (NUST)

In the current research work Ba_(1-x)La)xMn)yFe_(12-y)O_(19) hexa-ferrite nanoparticles of different compositions were synthesized using chemical co-precipitation technique. The structural properties were explored using X-ray diffractions(XRD), scanning electron microscopy(SEM) and Fourier transmission infrared spectroscopy(FTIR). XRD indexed pattern confirms the formation of M-type hexagonal phase. The crystallite size of synthesized samples ranges from 13 to 34 ± 2 nm. FTIR peaks observe also confirmed the presence of metaloxygen bond of the desired product. The position of peak at 467 cm^(-1) corresponds to A_2 u vibration for octahedral Fe(4+)-O and peak position E1 u corresponds to vibration of Fe(3+)O4 octahedral bonds. The band v_1 in range(677-559 cm^(-1)) and v_2 in frequency range(356-419 cm^(-1)) are associated to A and B *** properties of all compositions were measured with frequency. The dielectric constant, loss and tangent loss decrease from 26 to 9, 25 to 2 and 0.94 to 0.14, respectively with frequency. DC electrical resistivity is increased with dopant concentration increasing from 2.15 × 10~4 to 1.92 ×10~5 Ω·cm.

关键词： Co-precipitation Electrical properties Dielectric X-ray diffraction Rare earths

Combined stochastic and discrete simulation to optimise the economics of mixed single-horizontal and multilateral well offshore oil developments

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Petroleum Exploration and Development 2021年第5期48卷 1183-1197页

作者： ALMEDALLAH Mohammed ALTAHEINI Suleiman khalid CLARK Stuart WALSH Stuart University of New South Wales Sydney 2052Australia Monash University Victoria 3800Australia

Multilateral wells promise cost savings to oil and fields as they have the potential to reduce overall drilling distances and minimize the number of slots required for the surface facility managing the ***,drilling a multilateral well does not always increase the flow rate when compared to two single-horizontal wells due to competition in production inside the ***,a holistic approach is proposed to find the optimum balance between single and multilateral wells in an offshore oil *** so doing,the integrated approach finds the highest Net Present Value(NPV)configuration of the field considering drilling,subsurface,production and financial *** model employs stochastic perturbation and Markov Chain Monte-Carlo methods to solve the global maximising-NPV *** addition,a combination of Mixed-Integer Linear Programming(MILP),an improved Dijkstra algorithm and a Levenberg-Marquardt optimiser is proposed to solve the rate allocation *** the outcome from this analysis,the model suggests the optimum development including number of multilateral and single horizontal wells that would result in the highest *** results demonstrate the potential for modelling to find the optimal use of petroleum facilities and to assist with planning and decision making.

关键词： multilateral well horizontal well well pattern optimisation drilling cost Net Present Value offshore oil development

Direct Model Predictive Control of Noninverting Buck-boost DC-DC Converter

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CES Transactions on Electrical Machines and Systems 2022年第3期6卷 332-339页

作者： Basharat Ullah Hikmat Ullah Sumeet khalid IEEE Electrical and Computer Engineering COMSATS University IslamabadAbbottabad 22060Pakistan School of Information and Communication Engineering Harbin Institute of TechnologyHarbinP.R.150006China

In this paper, direct model predictive control(DMPC) of the noninverting buck-boost DC-DC converter with magnetic coupling between input and output is proposed. Unlike most of the other converters, the subject converter has the advantage of exhibiting minimum phase behavior in the boost mode. However, a major issue that arises in the classical control of the converter is the dead zone near the transition of the buck and boost mode. The reason for the dead zone is practically unrealizable duty cycles, which are close to zero or unity, of pulse width modulation(PWM) near the transition region. To overcome this issue, we propose to use DMPC. In DMPC, the switches are manipulated directly by the controller without the need of ***, avoiding the dead zone altogether. DMPC also offers several other advantages over classical techniques that include optimality and explicit current constraints. Simulations of the proposed DMPC technique on the converter show that the dead zone has been successfully avoided. Moreover, simulations show that the DMPC technique results in a significantly improved performance as compared to the classical control techniques in terms of response time, reference tracking, and overshoot.

关键词： Noninverting buck-boost DC-DC converter Direct model predictive control Dead zone avoidance

Global geoepidemiology of gastrointestinal surgery rates in Crohn’s disease

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1835-1844页

作者： Simcha Weissman Muhammad Aziz Ayrton Bangolo Vignesh K Nagesh Htat Aung Midhun Mathew Lino Garcia Shiva A Chandar Praveena Karamthoti Harinder Bawa Aseel Alshimari Yabets Kejela Nazish Mehdi Chrishanti A Joseph Athri Kodali Rohan Kumar Priya Goyal Sanya Satheesha Fnu Nivedita Nicole Tesoro Tanni Sethi Gurpreet Singh Areej Belal Alina Intisar Hirra khalid Samuel Cornwell Suchith B Suresh Kareem Ahmed Karabo K Marole Om P Anand Rahat B Reshi Tej I Mehta Sameh Elias Joseph D Feuerstein Department of Medicine Hackensack Meridian Health Palisades Medical CenterNorth BergenNJ 07047United States Division of Gastroenterology and Hepatology University of Toledo Medical CenterToledoOH 43614United States Department of Medicine University of WashingtonSeattleWA 98195United States Department of Radiology Johns Hopkins University HospitalBaltimoreMD 21218United States Division of Gastroenterology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMA 02215United States

BACKGROUND Data regarding the worldwide gastrointestinal surgery rates in patients with Crohn’s disease(CD)remains *** To systematically review the global variation in the rates of surgery in *** A comprehensive search analysis was performed using multiple electronic databases from inception through July 1,2020,to identify all full text,randomized controlled trials and cohort studies pertaining to gastrointestinal surgery rates in adult patients with *** included continent based demographic data,CD surgery rates over time,as well as the geoepidemiologic variation in CD surgery *** analyses were conducted using *** Twenty-three studies spanning four continents were *** median proportion of persons with CD who underwent gastrointestinal surgery in studies from North America,Europe,Asia,and Oceania were 30%(range:1.7%-62.0%),40%(range:0.6%-74.0%),17%(range:16.0%-43.0%),and 38%*** clear association was found regarding the proportion of patients undergoing gastrointestinal surgery over time in North America(R^(2)=0.035)and Europe(R^(2)=0.100).A moderate,negative association was seen regarding the proportion of patients undergoing gastrointestinal surgery over time(R^(2)=0.520)in *** There appears to be significant inter-continental variation regarding surgery rates in *** evidencebased guidelines accounting for the geographic differences in managing patients with CD is ***,as a paucity of data on surgery rates in CD exists outside the North American and European continents,future studies,particularly in less studied locales,are warranted.

关键词： Gastrointestinal surgery Crohn’s disease Geoepidemiology Inflammatory bowel disease Prevalence

Epidemiology of varicocele

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Asian Journal of Andrology 2016年第2期18卷 179-181,J0002页

作者： Bader Alsaikhan khalid Alrabeeah Guila Delouya Armand Zini Division of Urology Department of Surgery McGill University Montreal Quebec Canada Department of Urology College of Medicine King Saud bin Abdulaziz University for Health Sciences Riyadh Kingdom of Saudi Arabia Department of Radiology Research Centre of the University of Montreal Hospital Centre Quebec Canada.

Varicocele is a common problem in reproductive medicine practice. A varicocele is identified in 15% of healthy men and up to 35% of men with primary infertility. The exact pathophysiology of varicoceles is not very well understood, especially regarding its effect on male infertility. We have conducted a systematic review of studies evaluating the epidemiology of varicocele in the general population and in men presenting with infertility. In this article, we have identified some of the factors that can influence the epidemiological aspects of varicoceles. We also recognize that varicocele epidemiology remains incompletely understood, and there is a need for well-designed, large-scale studies to fully define the epidemiological aspects of this condition.

关键词： epidemiology infertility varicocele

Decoherence Effects on Multiplayer Cooperative Quantum Games

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Communications in Theoretical Physics 2011年第8期56卷 228-234页

作者： Salman Khan M.Ramzan M.khalid.Khan Department of Physics Quaid-i-Azam University

We study the behavior of cooperative multiplayer quantum games [Q. Chen, Y. Wang, J.T. Liu, and K.L. Wang, Phys. Lett. A 327 （2004） 98; A.P. Flitney and L.C.L. Hollenberg, Quantum Inf. Comput. 7 （2007） 111] in the presence of decoherence using different quantum channels such as amplitude damping, depolarizing and phase damping. It is seen that the outcomes of the games for the two damping channels with maximum values of decoherence reduce to same value. However, in comparison to phase damping channel, the payoffs of cooperators are strongly damped under the influence amplitude damping channel for the lower values of decoherence parameter. In the case of depolarizing channel, the game is a no-payoff game irrespective of the degree of entanglement in the initial state for the larger values of decoherence parameter. The deeoherenee gets the cooperators worse off.

关键词： multiplayer cooperative quantum games payoffs Nash equilibria

The role of dilatancy in shallow overburden tunneling

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Underground Space 2019年第3期4卷 181-200页

作者： Muhammad Shehzad khalid Mamoru Kikumoto Ying Cui Kiyoshi Kishid Department of Urban Management Kyoto UniversityNishikyo-KuKyoto 615-8540Japan Department of Civil Engineering Yokohama National UniversityYokohamaKanagawa 240-8501Japan

The mechanical behavior of sandy ground during shallow circular tunneling is explored for various overburden heights H(=0.5D,1.0D,1.5D and 2.0D;D is the diameter of the tunnel)and various dilatancy coefficients(w//=0,1/3,1/2,and 1;/and w are the internal friction angle and dilation angle,respectively)through finite difference *** ground is modeled as a linear elastic-perfectly plastic material that employs the Mohr-Coulomb yield criterion and obeys the non-associated flow *** ground reaction curve is applied in conjunction with the stress path as a conceptual tool for interpreting the mechanical response of the ground to *** is revealed that,at a certain relaxation value,a yield zone develops during tunneling and extends to the *** relaxation value increases with increases in the overburden and w//values for the cases of less shallow tunnels(i.e.,H=1.0D,1.5D and 2.0D),while for the shallowest case(H=0.5D),the extent of the yield zone to the ground surface is not sensitive to the w//*** shear strain due to tunneling also increases with an increase in the w//***,the w//value affects the radial displacement and the surface settlement due to *** magnitudes of the surface settlement and the radial displacement at the tunnel crown both decrease with an increase in the w//*** relative difference in the displacement at the tunnel crown between the upper bound and lower bound values,w//(at the last computed stage),increases with an increase in the overburden *** is recommended,therefore,that careful consideration be given to the dilatancy angle in the case of relatively less shallow tunnels.

关键词： Shallow tunnels Dilatancy Overburden Ground reaction curve Stress path