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Prevalence and Molecular Diagnosis of Viruses Infecting Fig Trees in Saudi Arabia
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作者 muhammad zaman Mahmoud A.Amer +4 位作者 muhammad Amir Zaheer Khalid muhammad Taimoor Shakeel Ibrahim M.Al-Shahwan Mohammed A.Al-Saleh 《Phyton-International Journal of Experimental Botany》 2025年第3期897-910,共14页
The common fig(Ficus carica L.),Moraceae family,is a commonly grown fruit tree in the Mediterranean region.Fig mosaic disease(FMD)poses a substantial threat to Saudi Arabia’s fig-producing economy.A survey was conduc... The common fig(Ficus carica L.),Moraceae family,is a commonly grown fruit tree in the Mediterranean region.Fig mosaic disease(FMD)poses a substantial threat to Saudi Arabia’s fig-producing economy.A survey was conducted during the two seasons of 2021 and 2022 on fig trees,displaying various fig mosaic disease symptoms.A total of 200 fig leaves and fruit samples were collected from various governorates in several Regions of Saudi Arabia including Riyadh,Tabuk,Hail,Qassim,Al-Jouf,Makkah,Jazan,Al-Madinah,Asir,and Northern Borders.These samples were tested by reverse transcription polymerase chain reaction(RT-PCR)with specific pairs of primers to assess the existence of Fig mosaic virus(FMV),Fig leaf mottle-associated virus 1(FLMaV-1),Fig leaf mottle-associated virus 2(FLMaV-2),Fig mild mottle-associated virus(FMMaV)and Fig fleck-associated virus(FFkaV).The results indicate that four viruses were found in mixed infections and tested positive.FMV was detected with a high infection rate of 46%followed by FLMaV-2 with an infection rate of 20%,FMMaV with an infection rate of 16%,and FLMaV-1 with an infection rate of 7%,respectively,while FFkaV was negative in all tested samples.Sequencing and phylogenetic analysis results showed that the FMV isolates shared 90.3%similarity with other FMV isolates,particularly those from Bosnia and Herzegovina(KU198368).While FLMaV-1 showed 92.5%similarity with the reference isolate FLMaV-1(KX397035),the isolates of FLMaV-2 exhibited 94.7%similarity with reference FLMaV-2 isolate(FN687742),and the isolate of FMMaV showed 94%similarity with reference FMMaV isolate(MG242131)based on sequence comparison.According to the RT-PCR results,FMV was effectively identified in all five fig varieties(Al Faiz Yellow,Asali,Brown Turkey,Iraqi,and Kaab Al-Ghazal).Contrarily,none of these varieties had FLMaV-1,FLMaV-2,or FMMaV.This study investigates the occurrence and economic impact of the viruses that infect fig trees in Saudi Arabia.This suggests that FMV is the primary virus infecting these fig varieties and there is no co-infection with the other tested viruses.These findings underscore the urgent need for implementing region-specific management strategies,such as breeding resistant cultivars,enforcing phytosanitary measures to limit virus spread,and prioritizing vector control to mitigate the economic impact of FMD on Saudi Arabia’s fig industry. 展开更多
关键词 FIG FMD viruses GRAFTING RT-PCR SEQUENCING
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太阳能喷灌系统供给能源与水力性能关系 被引量:3
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作者 刘俊萍 许继恩 +1 位作者 李滔 muhammad zaman 《排灌机械工程学报》 CSCD 北大核心 2021年第6期637-642,共6页
为了解决太阳能喷灌系统应用中无法对喷头水力性能进行有效预测的问题,以光照强度为影响因素,太阳能喷灌系统泵出口流量、泵出口压力、喷洒射程、水量分布及系统灌溉均匀性系数为评价指标,通过在夏季典型天气25~36℃下的系统水力性能试... 为了解决太阳能喷灌系统应用中无法对喷头水力性能进行有效预测的问题,以光照强度为影响因素,太阳能喷灌系统泵出口流量、泵出口压力、喷洒射程、水量分布及系统灌溉均匀性系数为评价指标,通过在夏季典型天气25~36℃下的系统水力性能试验,寻找不同光照强度下系统喷洒水力性能的变化规律,获得系统最佳工作状态下所需光照强度.试验结果表明:随着光照强度的增大,系统流量及泵出口压力均增大,泵的流量和压力随光照强度的变化规律基本符合指数分布规律.当光照强度大于900.0 W/m^(2)时,系统流量、泵出口压力、射程及水量分布基本保持不变.获得了平均光照强度与均匀性系数函数关系,当光照强度大于900.0 W/m^(2)时,系统喷灌均匀系数大于88%.当光照强度为200.0~600.0 W/m^(2)时,系统喷灌均匀系数为76%~82%.太阳能喷灌系统在光照强度大于200.0 W/m2时可正常工作.该研究为改善太阳能喷灌系统水力性能,促进太阳能喷灌系统在实际工程中的推广应用提供了参考. 展开更多
关键词 喷灌系统 太阳能 水力性能 光照强度 喷灌均匀系数
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Occurrence of Conspecific in the Neighboring Space Influence on Flight Initiation Distance in Cape Hare <i>Lepus capensis</i>under Human Stimuli
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作者 muhammad zaman Bushra Allah Rakha +3 位作者 Kwasi Wrensford Mengyan Zhu Longcheng Fan Guangshun Jiang 《Open Journal of Ecology》 2020年第6期380-395,共16页
Optimal escape theory predicts that animals would balance the costs and benefits of flight. One cost of not fleeing is the ongoing cost of vigilance for upcoming environmental threats. Our results show that FID increa... Optimal escape theory predicts that animals would balance the costs and benefits of flight. One cost of not fleeing is the ongoing cost of vigilance for upcoming environmental threats. Our results show that FID increases for vigilant hares with predator starting distance, due to the costs acquired by continuing to scan for ecological dangers. The presence of conspecifics within proximity distance for social hare was reduced FID due to collective vigilance, while a solitary animal had greater FID, due to less cooperative defense for predator detection. In both seasons, detection and flight initiation distance of the focal hare increased in open habitat due to a higher probability of detection for upcoming danger, while dense cover provided concealment but reduced the probability of detecting an incoming threat, reducing FID. Moreover, proximity to roads and the nearest refuge significantly influenced anti-predator risk by compensation energy to cope with approaching stimuli. In a landscape with heavy human hunting in retaliation to plantations damage has modified the natural behavior of the hare in the Shigar valley. The findings are discussed in the context of hare FID by humans and the suggestions for management and mitigation of human-wildlife conflict are also considered. 展开更多
关键词 Alert Distance Distance to Refuge Flight Initiation Distance (FID) Group Size Effect Starting Distance Social or Solitary Hare
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Evaluation of SWAT Model performance on glaciated and non-glaciated subbasins of Nam Co Lake, Southern Tibetan Plateau, China 被引量:2
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作者 muhammad ADNAN KANG Shi-chang +3 位作者 ZHANG Guo-shuai muhammad Naveed ANJUM muhammad zaman ZHANG Yu-qing 《Journal of Mountain Science》 SCIE CSCD 2019年第5期1075-1097,共23页
This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau... This paper presents an assessment of the Soil and Water Assessment Tool(SWAT) on a glaciated(Qugaqie) and a non-glaciated(Niyaqu) subbasin of the Nam Co Lake. The Nam Co Lake is located in the southern Tibetan Plateau, two subbasins having catchment areas of 59 km^2 and 388 km^2, respectively. The scores of examined evaluation indices(i.e., R^2, NSE, and PBIAS) established that the performance of the SWAT model was better on the monthly scale compared to the daily scale. The respective monthly values of R^2, NSE, and PBIAS were 0.94, 0.97, and 0.50 for the calibration period while 0.92, 0.88, and -8.80 for the validation period. Glacier melt contribution in the study domain was simulated by using the SWAT model in conjunction with the Degree Day Melt(DDM) approach. The conjunction of DDM with the SWAT Model ensued improved results during both calibration(R^2=0.96, NSE=0.95, and PBIAS=-13.49) and validation (R^2=0.97, NSE=0.96, and PBIAS=-2.87) periods on the monthly time scale. Average contribution(in percentage) of water balance components to the total streamflow of Niyaqu and Qugaqie subbasins was evaluated. We found that the major portion(99.45%) of the streamflow in the Niyaqu subbasin was generated by snowmelt or rainfall surface runoff(SURF_Q), followed by groundwater(GW_Q, 0.47%), and lateral(LAT_Q, 0.06%) flows. Conversely, in the Qugaqie subbasin, major contributor to the streamflow(79.63%) was glacier melt(GLC_Q), followed by SURF_Q(20.14%), GW_Q(0.13%), and LAT_Q(0.089%). The contribution of GLC_Q was the highest(86.79%) in July and lowest(69.95%) in September. This study concludes that the performance of the SWAT model in glaciated catchment is weak without considering glacier component in modeling; however, it performs reasonably well in non-glaciated catchment. Furthermore, the temperature index approach with elevation bands is viable in those catchments where streamflows are driven by snowmelt. Therefore, it is recommended to use the SWAT Model in conjunction with DDM or energy base model to simulate the glacier melt contribution to the total streamflow. This study might be helpful in quantification and better management of water resources in data scarce glaciated regions. 展开更多
关键词 SWAT MODEL NAM Co Lake DEGREE-DAY MELT MODEL Streamflow HYDROLOGICAL Response Unit
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Counter-current three-phase fluidization in a turbulent contact absorber: A CFD simulation 被引量:1
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作者 Syed Shah Jehan Gillani Atta Ullah +2 位作者 muhammad zaman Imran Rafique Chugtai Mansoor Hameed Inayat 《Particuology》 SCIE EI CAS CSCD 2017年第6期51-67,共17页
A computational fluid dynamics study of three-phase counter-current fluidization occurring in a turbu- lent contact absorber was performed. A two-dimensional, transient Eulerian multi-fluid model was used, in which th... A computational fluid dynamics study of three-phase counter-current fluidization occurring in a turbu- lent contact absorber was performed. A two-dimensional, transient Eulerian multi-fluid model was used, in which the dispersed solid phase was modeled employing a kinetic theory of granular flow. The grid independence of the model, the effect of wall boundary conditions, the choice of granular temperature model, the effects of order of discretization scheme and drag models were studied for a base case setting, The results of simulations were validated against experimental results obtained from the literature. Once the model settings were finalized, simulations were performed for different gas and liquid velocities to predict the hydrodynamics of the absorber. Computed bed expansion and pressure drop were compared with experimental data. Good agreement between the two was found for low velocities of gas and liquid. 展开更多
关键词 MULTIPHASE COUNTER-CURRENT Computational fluid dynamics (CFD) FLUIDIZATION Turbulent contact absorber
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Measurement of ^(59)Co(ai,x)reaction cross sections with the fast neutrons based on the ^(9)Be(p,n)reaction
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作者 muhammad zaman muhammad Nadeem +3 位作者 muhammad Sahid Kwangsoo Kim Guinyun Kim Nguyen Thi Hien 《Chinese Physics C》 SCIE CAS CSCD 2021年第4期248-255,共8页
The cross sections of the ^(59)Co(n,x)reaction in the average energy range of 15.2-37.2 MeV were meas-ured using activation and an off-line γ-ray spectrometric technique.The neutrons were generated from the ^(9)Be(p,... The cross sections of the ^(59)Co(n,x)reaction in the average energy range of 15.2-37.2 MeV were meas-ured using activation and an off-line γ-ray spectrometric technique.The neutrons were generated from the ^(9)Be(p,n)reaction with proton beam energies of 25-45 MeV at the MC-50 Cyclotron facility of the Korean Institute of Radi-ological and Medical Sciences(KIRAMS).Theoretical cal lculations of neutron-induced reactions on ^(59)Co were per-formed using the nuclear model code TALYS-1.9.The results for the ^(59)Co(n,x)reactions were compared with the theoretical values obtained using TALYS-1.9 and the literature data provided in EXFOR and the TENDL 2019 nuc-lear data library.The theoretical values obtained using TALYS-1.9 with adjusted parameters are comparable to the experimental data.The measured reaction cross sections of a few radionuclides are new,and the others are compar-able to the literature data,and thus,they can strengthen the database.The present study on cross sections leads to useful insight into the mechanisms of ^(59)Co(n,x)reactions. 展开更多
关键词 ^(59)Co(n x)reaction cross sections average neutron energy of 15.2-37.2 MeV off-lineγ-ray spectrometry MCNPX 2.6.0 simulation TALYS-1.9
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