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Agricultural management practices and soil quality - A study on agricultural lands of Hanna Village, Balochistan, Pakistan
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作者 KHAN Alamgeer GUL Shamim +4 位作者 AGHA Syed Abdul Sadiq PANEZAI Sanaullah KHAN Nayab ZIAD Tariq akbar ali 《Journal of Mountain Science》 2025年第3期846-859,共14页
Agricultural management practices influence soil health.In this study,agricultural lands of cold arid Hanna village,Balochistan,Pakistan,were studied to assess soil properties and the abundance of soil macrofauna spec... Agricultural management practices influence soil health.In this study,agricultural lands of cold arid Hanna village,Balochistan,Pakistan,were studied to assess soil properties and the abundance of soil macrofauna species.Five orchards,five tree-based intercropping(TBI)systems,two croplands and a barren unprotected rangeland were sampled.Soil properties,such as texture,concentrations of organic matter(SOM),organic carbon(SOC),mineral nitrogen and bioavailable phosphorus,pH and electrical conductivity were analyzed.The abundance and species of soil surface-dwelling and upper soil layer-dwelling(0-5 cm)macrofauna were also measured.Orchards and croplands were older than TBI systems.than the same agricultural systems(cropland or orchards),which were under intense tillage practice or receiving no fertilizer input.Our results demonstrate that the diversified cropping systems with the reduced(shallow)tillage and the amendment of both synthetic and organic fertilizers,promoted soil quality in this cold-winter desert.This study is a source of evidence for the farmers of this region,which highlights the importance of conservation agriculture and crop diversification under TBI system for improving soil quality.It warrants further investigation to evaluate biological indicators of soil health(soil microbial biomass,microbial diversity,microfauna,mesofauna and macrofauna)being influenced by various management practices in this region.Furthermore,the relationship between soil quality and crop production under various management practices in this region needs to be evaluated.Such an extensive study will further help encourage farmers to adopt the best management practice in their fields. 展开更多
关键词 Soil macrofauna Land use history Conservation agriculture Tree-based intercropping Quetta district
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在线固相萃取预富集-原子吸收联用测定痕量Fe(Ⅱ)和总铁量 被引量:16
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作者 徐光明 叶映雪 +2 位作者 殷学锋 沈宏 akbar ali 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2000年第3期350-353,共4页
以 1 ,1 0 -二氮菲 (1 ,1 0 -phen)为配合剂 ,乙醇为洗脱液 ,在 C1 8柱上将流动注射固相萃取预富集 -原子吸收光谱联用测定痕量 Fe( )和总铁 .Fe( )的含量可通过抗坏血酸还原后用差示法测得 .本法灵敏度高 ,选择性好 ,能在线分离干扰富... 以 1 ,1 0 -二氮菲 (1 ,1 0 -phen)为配合剂 ,乙醇为洗脱液 ,在 C1 8柱上将流动注射固相萃取预富集 -原子吸收光谱联用测定痕量 Fe( )和总铁 .Fe( )的含量可通过抗坏血酸还原后用差示法测得 .本法灵敏度高 ,选择性好 ,能在线分离干扰富集 Fe( ) ,采样速度 80次 / h,富集倍数 1 9倍 ,检测下限为 3μg/ L,相对标准偏差 1 .1 % (n=1 0 ) ,可用于测定水样中痕量 Fe( )和 Fe( ) ,回收率为 94 %~ 1 0 5% 展开更多
关键词 流动注射 原子吸收 在线预富集 铁测定 痕量分析
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因子分析-氢化物发生原子吸收法分析砷的形态 被引量:17
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作者 殷学锋 徐光明 +2 位作者 谷雪 杨炜春 akbar ali 《分析化学》 SCIE EI CAS CSCD 北大核心 1999年第7期798-801,共4页
报道了用流动注射氢化物发生原子吸收法(FI-HGAAS)对砷4种形态(As(Ⅲ),As(Ⅲ),DMA,MMA)的混合体系进行测量后,根据吸光度加和性原则,用因子分析法(TFA)对测定值进行解析,从而测定了混合体系中砷存在形态的数目、种类和含量.实验结果表明... 报道了用流动注射氢化物发生原子吸收法(FI-HGAAS)对砷4种形态(As(Ⅲ),As(Ⅲ),DMA,MMA)的混合体系进行测量后,根据吸光度加和性原则,用因子分析法(TFA)对测定值进行解析,从而测定了混合体系中砷存在形态的数目、种类和含量.实验结果表明,不同酸度介质中不同形态砷校正曲线的斜率可作为相应的目标检验向量,应用于μg/L级低浓度砷的形态分析,平均回收率为93.9%,结果令人满意. 展开更多
关键词 因子分析 流动注射 氢化物发生法 形态分析
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PTEN as a Novel Diagnostic and Prognostic Biomarker of Head and Neck Squamous Cell Carcinoma
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作者 Zain ali akbar ali 《Proceedings of Anticancer Research》 2024年第4期75-86,共12页
This review article explores phosphatase and tensin homolog(PTEN)’s role in head and neck squamous cell carcinoma(HNSCC)through comprehensive expression and methylation examinations,genetic mutation investigation,and... This review article explores phosphatase and tensin homolog(PTEN)’s role in head and neck squamous cell carcinoma(HNSCC)through comprehensive expression and methylation examinations,genetic mutation investigation,and prognostic evaluation.Using the UALCAN informational collection,PTEN expression examination uncovered a critical over-expression in HNSCC cells isolated from normal control samples,proposing its role in HNSCC multiplication.Further,analysis of PTEN expression across various clinical limits has shown critical up-regulation in different cancer development stages,racial groups,gender,and age classes within the context of HNSCC patients,suggesting its major role in cancer duplication.PTEN expression was validated by utilizing the GEPIA2.0 online tool,which showed PTEN expression was particularly significantly expressed in HNSCC cancer improvement when it appeared differently from normal control samples.Accordingly,examining PTEN validation across different phases of cancer advancement showed dysregulation in each of the four phases with the most raised expression in stage I and the least expression in stage IV.Thus,this study investigated the promoter methylation level of PTEN,figuring out a basic relationship between HNSCC samples and normal control samples.Analyzing promoter methylation across various clinical limits uncovered massive variations,with specific methylation patterns seen across malignant growth stages,race groups,gender,and age groups.Overall survival and disease-free survival(OS and DFS)utilizing the KM plotter tool showed a critical relationship between PTEN expression levels in HNSCC patients,showing high PTEN expression exhibited good overall survival when showed up distinctively comparable to low PTEN expression levels.In addition,in disease-free survival(DFS)evaluation HNSCC patients showing low PTEN expression experienced great DFS relative to HNSCC patients with high PTEN expression.Moreover,to validate PTEN expression against survival,the study examined the HNSCC patients into low and high-expression groups of PTEN.In HNSCC,low PTEN expression was connected with great overall survival(OS)when it appeared contrastingly relative to the high PTEN expression.In like manner,the study found that low PTEN expression level was connected with great DFS in HNSCC when it appeared contrastingly related to the high PTEN expression group.Genetic mutation analysis via cBioPortal identifies a minimal proportion of PTEN mutations in HNSCC,predominantly in-frame mutation,missense mutation,splice mutation,truncating mutation,and structural variant,indicating their basal significance in PTEN dysregulation within HNSCC.Further investigation of PTEN molecular components and their exchange inside the HNSCC microenvironment might disclose novel roads for designated treatment and accurate medication approaches in battling this harmful disease. 展开更多
关键词 Head and neck squamous cell carcinoma DIAGNOSIS TREATMENT BIOMARKER
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印度河流域文明遗传层次的比较生物学分析
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作者 KHAN Muhammad Hidayatullah KHAN Muhammad Asadullah +1 位作者 akbar ali 岳剑 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第S01期62-66,共5页
本文探索了约公元前2600年~公元1900年之间超过半个世纪印度古文明.由于气候、经济和社会的变化,使得其神秘消失,它被埋藏了将近4 000年,直到英国和印度的考古学家在1920年偶然发现了它的废墟才被揭晓.印度河流域有超过1 000个定居点,... 本文探索了约公元前2600年~公元1900年之间超过半个世纪印度古文明.由于气候、经济和社会的变化,使得其神秘消失,它被埋藏了将近4 000年,直到英国和印度的考古学家在1920年偶然发现了它的废墟才被揭晓.印度河流域有超过1 000个定居点,覆盖了至少100万平方公里,即目前的巴基斯坦和印度西北部.它是当时最大的城邦文明,拥有一百万人口和强大的海军出口贸易到海湾和美索不达米亚(乌尔)的城市,在那里发现了刻有印度河符号的物品.在20世纪末,发现了两个最大的遗址,即莫亨霍达罗和哈拉帕,这些遗址以其完善的城市卫生设施,精美的宝石首饰和石雕而著称.对哈拉帕(巴基斯坦)和法玛纳(印度)地区人类牙齿同位素数据(锶和铅)的分析,可以探究地球生物的化学迁移史和印度河域墓葬传统.另外,生物考古学的分析还揭示了由于气候变化和社会经济的破坏,疾病(包括传染病、创伤、关节病和牙科疾病)发病率从古到今都在增加.本文也为研究过去种群内部和种群之间的遗传关系提供了线索. 展开更多
关键词 印度河谷文明 哈拉帕 莫亨霍达罗 巴基斯坦考古遗址
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社区吸烟者心理特质及其对尼古丁依赖程度的影响研究 被引量:14
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作者 马含俏 刘涵 +4 位作者 金倩莹 乔昆 ali akbar 张曼华 李星明 《中国全科医学》 CAS 北大核心 2020年第15期1889-1894,1903,共7页
背景心理社会因素是影响尼古丁依赖的重要因素,关于吸烟原因和心理社会因素联合影响尼古丁依赖程度的研究较少见。目的调查北京市社区吸烟人群心理健康状况,并探讨其对尼古丁依赖程度的影响。方法2018-2019年,采用横断面研究方法,通过... 背景心理社会因素是影响尼古丁依赖的重要因素,关于吸烟原因和心理社会因素联合影响尼古丁依赖程度的研究较少见。目的调查北京市社区吸烟人群心理健康状况,并探讨其对尼古丁依赖程度的影响。方法2018-2019年,采用横断面研究方法,通过现场发放问卷调查北京市12家社区的吸烟者407人,纳入戒烟干预研究队列,采用自编社会人口学问卷收集吸烟者的人口学信息,采用尼古丁依赖量表评估吸烟者尼古丁依赖程度,采用拒烟自我效能问卷、Russell吸烟原因问卷、领悟社会支持量表及特质应对方式问卷进行吸烟者心理特质的调查。探讨人口学信息和心理特质得分与尼古丁依赖量表得分的相关关系;以尼古丁依赖程度为因变量,采用多重线性回归分析探讨影响尼古丁依赖程度的心理特质指标。结果本调查共发放问卷407份,回收有效问卷309份,有效问卷回收率为75.9%。不同文化程度、平均月收入吸烟者尼古丁依赖程度比较,差异有统计学意义(P<0.05)。不同尼古丁依赖程度吸烟者拒烟自我效能问卷总分及积极/社会情景、消极/情绪情景、习惯/成瘾情景维度得分,Russell吸烟原因问卷中心理意向、手口活动、享乐、镇静、刺激、成瘾及自动因子得分比较,差异有统计学意义(P<0.05)。Spearman秩相关分析结果显示,文化程度(rs=-0.224)、拒烟自我效能问卷总分(rs=-0.398)及积极/社会情景维度(rs=-0.292)、消极/情绪情景维度(rs=-0.226)、习惯/成瘾情景维度(rs=-0.465)得分与尼古丁依赖程度呈负相关(P<0.05),Russell吸烟原因问卷中的心理意向(rs=0.120)、手口活动(rs=0.240)、享乐(rs=0.354,P<0.05)、镇静(rs=0.239)、刺激(rs=0.227)、成瘾(rs=0.426)和自动(rs=0.298)因子得分与尼古丁依赖程度呈正相关(P<0.05)。多重线性回归分析结果显示,文化程度(t=-3.151)、习惯/成瘾情景维度得分(t=-5.401)、享乐因子得分(t=2.736)和成瘾因子得分(t=3.111)是吸烟者尼古丁依赖程度的影响因素(P<0.05)。结论影响吸烟者尼古丁依赖程度的因素包括文化程度、习惯成瘾情境下的拒烟自我效能和吸烟原因中的享乐因素以及成瘾因素,应从社会心理层面与成瘾方面入手进行吸烟者的戒烟干预。 展开更多
关键词 吸烟 吸烟戒断 问卷调查 心理特质 尼古丁依赖 社区
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Structural and optoelectronic properties of CsLnZnTe_(3)(Ln=La,Pr,Nd and Sm) 被引量:2
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作者 Imad Khan Ihsan Ullah +4 位作者 Izaz Ul Haq akbar ali A.Dahshan Zahid ali Iftikhar Ahmad 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第3期388-396,I0003,共10页
Zinc telluride is a versatile wide band gap semiconductor used in many applications.But it has certain limitations like large dimensions and large band gaps.Introducing alkali metal to its bulk lattice(3D)can reduce i... Zinc telluride is a versatile wide band gap semiconductor used in many applications.But it has certain limitations like large dimensions and large band gaps.Introducing alkali metal to its bulk lattice(3D)can reduce its dimensions and lanthanide can produce a red shift in the energy gap by converting it into quaternary compounds.The alkali and lanthanide incorporated quaternary zinc tellurides CsLnZnTe_(3)(Ln=La,Pr,Nd and Sm)form layered crystal structure in which_(∞)^(2)[LnZnTe_(3)]-layers are separated by Cs+layer.The famous lanthanide contraction is experimental both from lattice constants and bond lengths.The calculated band gaps are 2.26,2.28,2.12,2.05 eV for CsLaZnTe_(3),CsPrZnTe_(3),CsNdZnTe_(3) and CsSmZnTe_(3),respectively.These compounds show direct band gap nature.The energy band gaps of these compounds have not been evaluated yet both experimentally and theoretically.Energy loss functions,refractive index and dielectric functions were also calculated to explore the potential applications of CsLnZnTe_(3) in optoelectronic devices. 展开更多
关键词 CHALCOGENIDES Optical materials Electronic structure Dimensions reduction Ab-initio calculations Rare earths
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Surface Analysis of Etched Silicon
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作者 Arifullah   Qadeer Hussain +2 位作者 Nazir A. Naz Ammar akbar akbar ali 《Journal of Surface Engineered Materials and Advanced Technology》 2014年第2期98-104,共7页
P-type (100) oriented silicon wafers were etched with vapors of concentrated Hydrofluoric acid in a reaction chamber under continuous vapor-flow at standard temperature and pressure. The surface morphology of the etch... P-type (100) oriented silicon wafers were etched with vapors of concentrated Hydrofluoric acid in a reaction chamber under continuous vapor-flow at standard temperature and pressure. The surface morphology of the etched samples was examined by scanning electron microscope and pore size analyzer. The radius of the pores and quantum dots were found to be 6 nm and 4 nm respectively. Etched samples emitted red luminescence when exposed to ultra violet (UV) light. The red luminescence emitted by the etched surface has been assigned to energy states induced by quantum confinement of holes. 展开更多
关键词 SEMICONDUCTORS PS SEM TG/DTA
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Structural Characteristics of Porous Silicon
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作者 Qadeer Hussain Arifullah   +2 位作者 Nazir A. Naz Ammar akbar akbar ali 《Journal of Surface Engineered Materials and Advanced Technology》 2014年第2期105-110,共6页
Silicon wafers (p-type) were etched under continuous flow of HF vapors in a reaction chamber at standard temperature and pressure. Etched surface of the silicon wafer was found emitting red luminescence when exposed t... Silicon wafers (p-type) were etched under continuous flow of HF vapors in a reaction chamber at standard temperature and pressure. Etched surface of the silicon wafer was found emitting red luminescence when exposed to ultra violet (UV) light. XRD and Atomic Force Microscopy of the etched samples were carried out to study the surface of the etched silicon. It is noticed that etching has removed the stress induced atomic layers of silicon at grain boundaries and layer of porous silicon has been formed at the surface of silicon wafer which has higher inter planer distance than the silicon itself. The size of dots observed on the surface of etched silicon is of the order of few nm. The red emission from the surface of etched silicon appears to be due to the energy states induced by quantum confinement. 展开更多
关键词 PS XRD ELECTRON CONFINEMENT
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Deep Level Transient Spectroscopy of AlGaInP LEDs
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作者 M. Atiq Nazir A. Naz akbar ali 《Journal of Modern Physics》 2014年第18期2075-2079,共5页
Deep level transient spectroscopy (temperature scans) of AlGaInP based red light emitting diodes was carried out from 77 K to room temperature. At least ten defects were observed. Of these, five defects assigned to en... Deep level transient spectroscopy (temperature scans) of AlGaInP based red light emitting diodes was carried out from 77 K to room temperature. At least ten defects were observed. Of these, five defects assigned to energy states 0.21, 0.22, 0.24, 0.26, and 0.24 eV were characterized. Respective capture cross-sections, measured at infinite temperature (T = ∞), QUOTE were found to be 8.84 × 10-16, 6.98 × 10-16, 7.86 × 10-16, 9.9 × 10-16 and 2.1 × 10-16 cm2. Corresponding concentrations of defects were 3.7 × 1013, 3.5 × 1013, 3.2 × 1013, 3.3 × 1013 and 3.1 × 1013 cm-3. 展开更多
关键词 SEMICONDUCTORS MOCVD DEFECTS DLTS
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Optoelectronic and elastic properties of metal halides double perovskites Cs_(2)InBiX_(6)(X = F, Cl, Br, I)
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作者 Muhammad Saeed Izaz Ul Haq +5 位作者 Shafiq Ur Rehman akbar ali Wajid ali Shah Zahid ali Qasim Khan Imad Khan 《Chinese Optics Letters》 SCIE EI CAS CSCD 2021年第3期17-26,共10页
Structural geometry, electronic band gaps, density of states, optical and mechanical properties of double perovskite halides Cs2InBiX6(X = F, Cl, Br, I) are investigated using the density functional theory. These comp... Structural geometry, electronic band gaps, density of states, optical and mechanical properties of double perovskite halides Cs2InBiX6(X = F, Cl, Br, I) are investigated using the density functional theory. These compounds possess genuine perovskite stoichiometry, evaluated using various geometry-based indices like tolerance factor, octahedral factor, and formation energy. The fundamental electronic band gaps are direct and valued in the range 0.80–2.79 e V. These compounds have narrow band gaps(except Cs2InBiX6) due to strong orbital coupling of the cations. The valence band maximum and conduction band minimum are confirmed to be essentially of In 5 s and Bi 6 p characters, respectively. The splitting of Bi 6 p bands due to strong spin-orbit coupling causes reduction in the band gaps. These compounds have large dispersion in their bands and very low carrier effective masses. The substitution of halogen atoms has great influence on the optical properties. The mechanical properties reveal that Cs2InBiX6(X = F, Cl, Br, I) satisfy the stability criteria in cubic structures. 展开更多
关键词 optical materials metal halides density functional theory perovskite stoichiometry spin-orbit coupling
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医学生与临床医生健康教育学习需求差异化分析 被引量:1
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作者 王星雨 刘涵 +6 位作者 闫佳惠 王尧 金倩莹 马含俏 akbar ali 陈天祚 李星明 《中华健康管理学杂志》 CAS CSCD 2019年第2期118-122,共5页
目的了解医学生与临床医生对健康教育内容的需求度现况及差异。方法采用分层抽样方法,抽取某医科大学在校医学生511名(女性303名,男性208名),并以436名临床医生(女性144名,男性292名)调查结果为参照,对医学生与临床医生慢病管理的知识... 目的了解医学生与临床医生对健康教育内容的需求度现况及差异。方法采用分层抽样方法,抽取某医科大学在校医学生511名(女性303名,男性208名),并以436名临床医生(女性144名,男性292名)调查结果为参照,对医学生与临床医生慢病管理的知识与技能方面的学习需求内容进行分析,医学生与临床医生的学习需求度差异比较采用χ2检验。结果服药依从性、戒烟干预、合理膳食、中医康复技术、移动健康技术应用、运动康复指导及健康促进理论的学习需求度在临床医生与医学生之间,差异具有统计学意义(P<0.01),其中服药依从性、戒烟干预及运动康复指导,医学生认为需要的比例分别为87.1%、82.2%及81.2%,而医生认为这3项内容需要的比例则高达96.3%、93.8%及92.8%。对心理压力管理、慢性传染病健康教育及急性传染病健康教育的需求度评价在临床医生与医学生之间比较差异无统计学意义(P>0.05)。结论医学生与临床医生对慢病管理知识学习需求的认识尚存在较大差距,与临床医生相比,医学生尚未完全认识到慢病管理知识与技能学习的重要性。建议在今后的医学教育中应加强临床医学健康教育的课程建设。 展开更多
关键词 健康教育 医师 学生
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