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Forest cover dynamics in Palas Valley Kohistan, Hindu Kush-Himalayan Mountains, Pakistan

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Journal of Mountain Science 2021年第2期18卷 416-426页

作者： Noor ul HAQ Fazlur RAHMAN Iffat TABASSUM MEHRAN Department of Geography University of PeshawarPeshawar 25120Pakistan Department of Urban and Regional Planning University of PeshawarPeshawar 25120Pakistan

Forest cover change in the mountainous region is driven by a variety of anthropogenic and natural *** Hindu Kush-Himalayan Mountains has experienced a considerable vegetation cover change due to intensive human activities,such as population growth,proximate causes,accessibility,unstable political situations,government policy failure and *** present study seeks to find out the impact of population growth and road network expansion on forest cover of Palas valley based on remotely sensed data and employing geospatial *** in forest cover were determined by classifying time-series satellite images of Landsat and Sentinel 2 *** images of October 1980,2000,2010 and 2017 were classified into six land cover classes and then the impact of population growth and accessibility on forest cover was ***,forest cover and land-use change detection map was prepared using classified images of 1980 and *** data were collected mainly from field visits(ground verification),census reports,Communication and Works Department,*** imageries were obtained from the United States Geological Survey’s websites and classified in ERDAS imagine 2014 and ESRI ArcGIS 10.2.1 using supervised classification-maximum likelihood *** of this study revealed that a substantial reduction in forest cover has taken place mainly in the proximity of human *** the average,during the study period,annually more than 460 hectares of forest area has been converted into other uses.

关键词： Forest cover changes Population growth Road networks Deforestation Palas Valley Pakistan

多种信号途径介导花生四烯酸与5-羟色胺在促人类血小板凝集中的协同作用(英文)

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Acta Pharmacologica Sinica 2003年第10期24卷 8-14+110页

作者： Sheikh Arshad SAEED,Huma RASHEED,Anwar-ul-Hassan GILANI Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan Department of Biological and Biomedical Sciences The Aga Khan University PO Box 3500 Stadium Road Karachi 748700 Pakistan

AIM: To examine the signalling mechanisms involved in the synergistic interaction of 5-hydroxytryptamine （5-HT） and arachidonic acid （AA） in human platelet aggregation. METHODS: Blood was obtained from healthy human subjects, mixed with 3.8% sodium citrate （9:1）, and centrifuged to prepare platelet rich plasma （PRP）. Aggregation was monitored using a Dual-channel Lumi-aggregometer. The agonist-induced influx of Ca2+was measured using Fura-2 AM. TXA2formation was studied using radiochemical method. RESulTS: Subthreshold concentration of 5-HT （2μmol/L） potentiated the effect of low dose of AA （0.2 mmol/L） in human platelets. This synergistic effect was blocked by 5-HT2receptor antagonist (methysergide IC50=5.2 nmol/L; cyproheptadine IC50=0.6 nmol/L), and thromboxane A2receptor antagonist (SQ 29 548; IC50=30 nmol/L), showing that the effect is receptor-mediated. To examine the down-stream signalling pathways, we found that such an interaction was inhibited by calcium channel blockers (d

关键词：血清素花生四烯酸类血小板聚集环氧化酶抑制剂美舍吉特塞庚啶血栓烷A2 磷脂酶C 钙药物协同作用

Anti-obesity effect and UHPLC-QTOF-MS/MS based metabolite profiling of Solanum nigrum leaf extract

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Asian Pacific Journal of Tropical Biomedicine 2022年第4期12卷 164-174页

作者： Zain ul Aabideen Muhammad Waseem Mumtaz Muhammad Tayyab Akhtar Muhammad Asam Raza Hamid Mukhtar Ahmad Irfan Syed Ali Raza Muhammad Nadeem Yee Soon Ling Department of Chemistry University of GujratGujratPakistan Institute of Industrial Biotechnology GC University LahoreLahorePakistan Department of Chemistry College of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Research Center for Advanced Materials Science King Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia Department of Chemistry GC University LahoreLahorePakistan Sabah Occupational Safety Health and Environment AssociationLot331st FloorBlock EIramanis CenterJalanLinatas88450Kota KinabaluSabahMalaysia

Objective:To evaluate the antioxidant potential and pancreatic lipase inhibitory action of optimized hydroethanolic extracts of Solanum ***:Optimized extraction for maximum recovery of metabolites was performed using a combination of freeze-drying and ultrasonication followed by determination of antioxidant and antiobesity *** ultra-high performance liquid chromatography equipped with mass spectrometry was used to analyze metabolite profiling of Solanum *** studies were performed using molecular docking and electrostatic potential analysis for individual *** hypolipidemic potential of the most potent extract was assessed in the obese mice fed on fat rich ***:The 80%hydroethanolic extract exhibited the highest extract yield,total phenolic contents,total flavonoid contents along with the strongest 2,2-diphenyl-1-picrylhydrazyl scavenging activity,total antioxidant power,and pancreatic lipase inhibitory *** 80%hydroethanolic extract not only regulated the lipid profile of obese mice but also restricted the weight gain in the liver,kidney,and *** 80%hydroethanolic extract also reduced alanine transaminase and aspartate transaminase concentrations in *** effects of plant extract at 300 mg/kg body weight were quite comparable with the standard drug ***:Solanum nigrum is proved as an excellent and potent source of secondary metabolites that might be responsible for obesity mitigation.

关键词： Solanum nigrum ultrasonication Metabolite profiling Total phenolic contents Total flavonoid content Antioxidant DPPH Total antioxidant power Pancreatic lipase UHPLC-QTOF-MS/MS Antiobesity Mice Hypolipidemic Molecular docking

Toxic and Antifeedant Effects of Different Pesticidal Plant Extracts against Beet Armyworm (Spodoptera exigua)

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Phyton-International Journal of Experimental Botany 2023年第4期92卷 1161-1172页

作者： Muhammad Asad Rashad Rasool Khan Ahmed B.Aljuboory Muhammad Haroon URashid Uttam Kumar Inzamam ul Haq Aqsa Hafeez Ahmed Noureldeen Khadiga Alharbi College of Life Science Fujian Agriculture and Forestry UniversityFuzhou350002China Department of Entomology University of AgricultureFaisalabad38000Pakistan Department of Plant Protection College of Agricultural Engineering ScienceUniversity of BaghdadBaghdad10071Iraq Department of Forestry and Range Management University of AgricultureFaisalabad38000Pakistan College of Plant Protection Fujian Agriculture and Forestry University Fuzhou350002China College of Plant Protection Gansu Agricultural UniversityLanzhou730070China Department of Plant Sciences Quaid-i-Azam UniversityIslamabad45320Pakistan Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Biology College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia

The beet armyworm(BAW),Spodoptera exigua(Lepidoptera:Noctuidae)is a highly destructive pest of vegetables and field *** of beet armyworm primarily relies on synthetic pesticides,which is threatening the beneficial community and *** importantly,the BAW developed resistance to synthetic pesticides with making it difficult to ***,alternative and environment-friendly pest management tactics are urgently *** use of pesticidal plant extracts provides an effective way for a sustainable pest management *** evaluate the use of pesticidal plant extracts against BAW,we selected six plant species(Lantana camara,Aloe vera,Azadirachta indica,Cymbopogon citratus,Nicotiana tabacum,and Ocimum basilicum)for initial screening *** out of six plant species such as ***,***,*** and *** showed promising mortality of more than 50%.Therefore,we selected these four plant extracts for the subsequent *** contact bioassay,*** showed high mortality 66.63%,followed by the *** 53.33%,at 10%w/v ***,*** showed the highest mortality rate,66%at 10%w/v concentration,followed by the *** 46%through feeding ***,the feeding deterrence assay showed that *** had a high antifeedant index(−50)followed by ***(−39),and ***(−28).In living plant assay,the *** extract showed a low mean damage score 3.6 on living cotton plant followed by *** 4.5 and *** ***,extracts of three plant species provided promising results against the BAW,which can minimize the use of synthetic chemicals,particularly for small landholding *** studies are also required to evaluate the effects of these plant extract against BAW on cotton plants under field conditions to optimize the further use.

关键词： Bioassay methods feeding deterrence botanical pesticide pest management sustainable agriculture

Combined Role of ACC Deaminase Producing Bacteria and Biochar on Cereals Productivity under Drought

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Phyton-International Journal of Experimental Botany 2020年第2期89卷 217-227页

作者： Subhan Danish Muhammad Zafar-ul-Hye Department of Soil Science Faculty of Agricultural Sciences and TechnologyBahauddin Zakariya UniversityMultan60800Pakistan Soil and Water Testing Laboratory PakArab Fertilizer LimitedPlantsiteMultan60800Pakistan

Most of the cereal crops are widely cultivated to fulfil the humans food *** changing climate scenario,the intensity of drought stress is continuously increasing that is adversely affecting the growth and yield of cereal *** the cereals can tolerate moderate drought to some extent,but mostly they are susceptible to severe drought *** biosynthesis of ethylene under drought stress has been *** scientists observed that inoculation of 1-aminocyclopropane-1-carboxylate(ACC)deaminase producing plant growth promoting rhizobacteria(PGPR)is an efficacious tool to overcome this *** PGPR secrete ACC deaminase which cleavage the ACC into the compounds,other than ***,secretion of growth hormones also play imperative role in enhancing the growth of the cereals under limited availability of *** addition,the use of biochar has also been recognized as another effective amendment to grant resistance against *** application improves the soil physiochemical attributes i.e.,porosity,nutrients retention and water holding capacity which decrease the loss of water and increase its *** recent era,the idea of coapplication of ACC deaminase producing PGPR and biochar is becoming popular which might be more efficient to use water under drought *** aim of current review is to combine the facts and understanding of this novel idea to grant maximum resistance to crops against drought *** scientists have observed significant improvement in yield of cereal crops by combined use of ACC deaminase producing PGPR and ***,more research is suggested for deep understanding of complex synergistic mechanism of ACC deaminase activity in combination with biochar.

关键词： ACC deaminase biochar cereals drought ethylene PGPR yield

Average Convergence for Directed&Undirected Graphs in Distributed Systems

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Computer Systems Science & Engineering 2021年第6期37卷 399-413页

作者： Ali Mustafa M Najam ul Islam Salman Ahmed Bahria University Islamabad44000Pakistan Comsats University Islamabad Attock campus43600Pakistan University of Engineering&Technology Peshawar25000Pakistan

Consensus control of multi-agent systems is an innovative paradigm for the development of intelligent distributed *** has fascinated numerous scientific groups for their promising applications as they have the freedom to achieve their local and global goals and make their own *** communication topologies based on graph and matrix theory are widely used in a various real-time applications ranging from software agents to ***,while sustaining the significance of both directed and undirected graphs,this research emphases on the demonstration of a distributed average consensus *** uses the harmonic mean in the domain of multi-agent systems with directed and undirected graphs under static topologies based on a control input *** proposed agreement protocol focuses on achieving a constant consensus on directional and undirected graphs using the exchange of information between neighbors to update their status values and to be able to calculate the total number of agents that contribute to the communication network at the same *** proposed method is implemented for the identical networks that are considered under the directional and non-directional communication *** different scenarios are simulated and it is concluded that the undirected approach has an advantage over directed graph communication in terms of processing time and the total number of iterations required to achieve *** same network parameters are introduced for both orientations of the communication *** addition,the results of the simulation and the calculation of various matrices are provided at the end to validate the effectiveness of the proposed algorithm to achieve consensus.

关键词： Multi-agent systems average consensus distributed estimation directed graphs undirected graphs agent counting

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深基坑双排支护桩受力特性研究

深基坑双排支护桩受力特性研究

作者： ZAIN ul ABDIN 西安理工大学

学位级别：硕士

当前,随着社会经济的逐步发展和越来越城市化,在土木建设工程中深基坑支护获得了越来越多的关注,也成为了时下的难点。靠近地铁隧道、地铁站等地下结构的深基坑支护结构,受附近地下建筑物和土体的约束,影响支护结构的支护方式和变形稳定... 详细信息

当前,随着社会经济的逐步发展和越来越城市化,在土木建设工程中深基坑支护获得了越来越多的关注,也成为了时下的难点。靠近地铁隧道、地铁站等地下结构的深基坑支护结构,受附近地下建筑物和土体的约束,影响支护结构的支护方式和变形稳定性,导致土压力分布不同本研究在前人研究的基础上,针对地铁隧道双排桩、基坑、基坑支护结构的联合作用,建立了三维有限元模型,采用大型通用计算程序ABAQUS模拟西安施工过程的单元计算模型。研究了有限宽度土深基孔双排桩支护系统的理想设计方法和变形特性,得出以下结论:1、在地铁隧道附近的深基坑工程中,双排桩能有效应对复杂的周边环境,减少基坑周围土体位移,为基坑开挖提供良好的支撑。本文介绍了双排桩支撑系统的参数优化:桩长33米,桩径1.2米,桩刚度,桩间距2D,桩排间距4D。2、双排桩支护结构与单排桩的变形特征不同:单排桩的变形曲线是上大下小的渐变曲线,而双排桩的变形曲线是上下小、中间大的弓形或双反弯点曲线。双排桩支撑体系中桩体的最大位移明显小于单排桩支撑结构。冠梁的存在可以极大地改变双排桩的变形状况,导致桩顶位移显著减小。前后桩会有一个中间大的弓形或双反弯点位移曲线并且两侧细小。3、双排桩支护系统受力或变形情况的变化,可由桩长、直径、刚度、桩间距、桩排间距的变化引起:使基坑周围的土壤更受限制。(1)桩长由27m增加到35m时,桩的最大水平位移降低了 2cm左右,降低幅度为29%。桩长可以改变双排桩支撑结构的变形形式,有效减小桩顶位移和最大位移,有效增加桩的嵌入效果。能有效减小双排桩的水平位移,有利于双排桩支护结构的稳定性。(2)桩径由0.6m增加至1.4m时,桩身最大水平位移降低3cm左右,降低幅度为38%°双排桩的横向抗弯刚度随着桩径的增加而增加,这显著增强了双排桩对基坑周围土体的限制作用。该技术有效地减少了基坑周围的水平土壤位移,同时还增加了双排桩支撑结构的稳定性。(3)当柱刚度从0.5EI增加到1.5EI时,桩的最大水平位移减少了 2.2cm左右,相关减少了 27%。增加桩身刚度,提高桩身对周围土体的抵抗力,从而减小桩身的水平位移,有利于双排桩支护系统的稳定性。(1)国家研究表明,当桩距从2D增加到6D时,后桩的最大水平位移增加了1.99cm,而前桩的最大水平位移增加了 3.3c,上升率分别为52%和75%,前排桩的水平位移增加比后排桩大得多。随着桩间距的增加,相同间距内的双排桩数量会减少,其横向抗弯能力会不知不觉地降低,这对基坑的支护条件是不利的。(2)桩排间距由2D增加到6D时,前后桩最大水平位移分别减少3.32cm和2.65cm,减少幅度分别为50.69%和38.97%。通过增加双排桩的桩排间距,可以调整桩间土壤的分布比例,从而减少桩的水平位移。随着桩排间距的增加,桩的水平位移会继续减小。1、针对双排桩不同弯矩分布特点,采用多种加固方法,降低工程造价:当桩长和单桩弯矩分布不同时,可采用分段加固。当前后排桩的直径和弯矩不同时,可以使用不对称加固。当桩排间距和单桩弯矩增加量不同时,可以同时使用分段配筋和不对称配筋。2、随着基础隧道距离从10米增加到30米,地铁隧道水平位移从5.6米下降到2.1米,相关减少62.9%;垂直位移从3.7米减少到0.7米,减少了 80.7%。由于减小幅度较大,水平和竖向位移均呈下降趋势。基坑开挖对地铁隧道的影响越明显,基坑与隧道的距离越近。地铁隧道的存在会使基坑与隧道距离较小时改变双排桩的力学变形性能,降低基坑与隧道之间的地表沉降,但地表沉降距离基坑末端会不断增加,地铁隧道对基坑有一定的屏蔽作用;当基坑与隧道距离较大时,基坑与隧道之间的地表沉降减小,但地表沉降远离。3、随着基坑开挖深度由15米增加到25米,地铁隧道水平位移由0.7厘米增加到11.6厘米,相差1426.3%;垂直位移由2.5cm增加到10.4cm,相差308.2%。横轴和纵轴位移均呈上升趋势,增长幅度异常大。基坑开挖对地铁管道的影响越大,基坑开挖深度越深。地铁隧道的存在对其紧邻的基坑开挖有重大影响。地铁隧道的存在可以改变基坑与地铁隧道之间的土体沉降方式,以及双排桩支护系统的变形特性。随着基坑开挖深度的增加,地铁隧道对基坑开挖的影响会逐渐减弱,双排桩支护结构的水平位移会明显增加,基坑周围的地表沉降会迅速增加。

关键词：深基坑双排桩地铁隧道有限元数值模拟

Assessment of Nutrient Leaching Losses and Crop Uptake with Organic Fertilization,Water Saving Practices and Reduced Inorganic Fertilizer

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Phyton-International Journal of Experimental Botany 2023年第5期92卷 1555-1570页

作者： Xiaotong Liu Muhammad Amjad Bashir Yucong Geng Qurat-ul-Ain Raza Abdur Rehim Muhammad Aon Jianhang Luo Ying Zhao Xuejun Zhang Hongbin Liu Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry SciencesYinchuan750002China Faculty of Agricultural Sciences and Technology Bahauddin Zakariya UniversityMultan60800Pakistan College of Agriculture University of LayyahLayyah31200Pakistan Key Laboratory of Nonpoint Source Pollution Control Ministry of AgricultureInstitute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural Sciences(CAAS)Beijing100081China

The increasing world population has forced excessive chemical fertilizer and irrigation to complete the global food demand,deteriorating the water quality and nutrient ***-term studies do not compile the evidences;therefore,the study aimed to identify the effectiveness of reduced doses of inorganic fertilizer and water-saving practices,hence,a six-year experiment(2015-2020)was conducted in China to address the knowledge *** experimental treatments were:farmer accustomed fertilization used as control(525:180:30 kg NPK ha^(-1)),fertilizer decrement(450:150:15 kg NPK ha^(-1)),fertilizer decrement+water-saving irrigation(450:150:15 kg NPK ha^(-1)),application of organic and inorganic fertilizer+water-saving irrigation(375:120:0 kg NPK ha^(-1)+4.5 tones organic fertilizer ha^(-1)),and application of controlled-release fertilizer(80:120:15 kg NPK ha^(-1)).Each treatment was replicated thrice following a randomized complete block *** results achieved herein showed that control has the highest losses in the six-year study for total nitrogen(225.97 mg L^(-1)),total soluble nitrogen(121.58 mg L^(-1)),nitrate nitrogen(0.93 mg L^(-1)),total phosphorus(0.57 mg L^(-1)),and total soluble phosphorus(0.57 mg L^(-1))*** fertilizer and water application improved crop nutrient uptake,nitrogen concentration was significantly enhanced with organic and inorganic fertilizer+water-saving irrigation,P concentration was increased with fertilizer decrement+water-saving irrigation,and K concentration was improved with fertilizer decrement+water-saving ***,this study concludes that reduced inorganic fertilizer dose combined with water-saving practices is significantly helpful in reducing nutrient leaching losses and improving nutrient uptake and water *** studies are needed to explore the impacts of reduced fertilization and water-saving irrigation on leaching *** benefits at different climatic conditions,soil types,and ferti

关键词： Corn production feeding system water consumption efficiency sustainable agriculture water use

基于深度学习的巴基斯坦国家输配电公司短期电力负荷预测案例研究

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基于深度学习的巴基斯坦国家输配电公司短期电力负荷预测案例研究

作者： Izaz ul Haq 兰州理工大学

学位级别：硕士

电力是当今时代广泛使用的主要能源,发电公司正试图不断监测和管理基础设施,以维持完美的供需平衡,电力能源的供需平衡对社会稳定和经济发展至关重要。为了实现可靠、可持续的电力供应,准确的负荷预测至关重要。由于电力系统每天都必须... 详细信息

电力是当今时代广泛使用的主要能源,发电公司正试图不断监测和管理基础设施,以维持完美的供需平衡,电力能源的供需平衡对社会稳定和经济发展至关重要。为了实现可靠、可持续的电力供应,准确的负荷预测至关重要。由于电力系统每天都必须安排次日的发电,因此日前短期负荷预测(short term load forecasting,STLF)是电力公司日常工作的重要组成部分,短期负荷预测指的是几个小时到几天的电力负荷预测。在本文中,提出了一种新的卷积神经网络(convolutional neural network,CNN)来评估STLF的性能。首次使用管理巴基斯坦全国电力负荷的国家级机构——国家输配电公司(national transmission and dispatched company,NTDC)的6年平均小时负荷数据集进行测试,并与其他应用的基准模型的结果进行比较。采用平均绝对百分比误差(mean absolute percentage error,MAPE)、均方根误差(root mean square error,RMSE)、R等5个评价指标对模型的精度进行评价。将所提出的模型与LSTM、ANN、RNN等8种不同的机器学习(machine learning,ML)和深度学习(deep learning,DL)模型进行了比较。研究了五种不同时间范围的STLF,例如提前一小时、提前一天、提前半天(12小时)、提前四分之一天(6小时)和提前三小时。预测结果表明,所提出的CNN模型可以作为巴基斯坦NTDC短期负荷预测工具。在实际应用中,该模型在25%的数据上进行训练,在不同的STLF层位上获得了93%-98%的精度,取得了很好的预测结果。

关键词：人工智能深度学习短期负荷预测神经网络电力系统