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Annual growth of Fagus orientalis is limited by spring drought conditions in Iran’s Golestan Province

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Journal of Forestry Research 2024年第1期35卷 128-142页

作者： Khalil Ghorbani jahangir mohammadi Laleh Rezaei Ghaleh Department of Water Engineering Faculty of Water and Soil EngineeringGorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Forestry Gorgan University of Agricultural Sciences and Natural ResourcesGorganIran Department of Water Engineering Faculty of AgricultureUrmia UniversityUrmiaIran

Due to the lack of a uniform and accurate defi-nition of‘drought’,several indicators have been introduced based on different variables and methods,and the efficiency of each of these is determined according to their relationship with *** relationship between two drought indices,SPI(standardized precipitation index)and SPEI(standard-ized precipitation-evapotranspiration index)in different sea-sons was investigated using annual rings of 15 tree samples to determine the effect of drought on the growth of oriental beech(Fagus orientalis Lipsky)in the Hyrcanian forests of northern *** different evapotranspiration calcula-tion methods were evaluated on SPEI efficiency based on Hargreaves-Samani,Thornthwaite,and Penman-monteith methods using the step-by-step m5 decision tree regression *** results show that SPEI based on the Penman-monteith in a three-month time scale(spring)had similar temporal changes and a better relationship with annual tree rings(R^(2)=0.81)at a 0.05 significant *** change and a decreasing trend in the time series of annual tree rings are similar to the variation in the SPEI based on the Penman-monteith *** affecting evapotranspiration,temperature,wind speed,and sunshine hours(used in the Penman-monteith method),increased but precipitation *** non-linear modeling methods,SPEI based on Penman-monteith best illustrated climate changes affecting tree growth.

关键词： Climate change Drought index Hyrcanian forests SPEI'Annual growth rings Fagus orientalis

基于机器学习算法的农田挥发氨多传感器阵列检测技术研究

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河南农业大学学报 2024年第2期58卷 269-278页

作者：耿宽 ATA jahangir moshayedi 张浩张伟胡建东河南农业大学机电工程学院河南郑州450002 省部共建小麦玉米作物学国家重点实验室河南郑州450002 河南省农业激光技术国际联合实验室河南郑州450002 江西理工大学信息工程学院江西赣州341000

【目的】设计能够快速、低成本、便捷检测农田挥发氨装置。【方法】构建基于二氧化锡(SnO_(2))半导体气体传感器阵列检测系统,并在新鲜空气(氨气质量浓度为0 mg·m^(-3))和氨气质量浓度分别为75.9、151.8、303.6 mg·m^(-3)条件下,以及... 详细信息

【目的】设计能够快速、低成本、便捷检测农田挥发氨装置。【方法】构建基于二氧化锡(SnO_(2))半导体气体传感器阵列检测系统,并在新鲜空气(氨气质量浓度为0 mg·m^(-3))和氨气质量浓度分别为75.9、151.8、303.6 mg·m^(-3)条件下,以及混合有乙醇的空气、纯乙醇气体(质量浓度为151.8 mg·m^(-3))、混合有氨气的空气和纯氨气气体(质量浓度为151.8 mg·m^(-3))样品下,通过主成分分析法(principal component analysis,PCA)、K-最近邻算法(K-nearest neighbors,KNN)和支持向量机算法(support vector machine,SVm)对多传感器阵列响应稳态阶段和暂态阶段的数据进行分类处理,分析该系统对不同质量浓度氨气和混合气体环境下氨气的区分效果。【结果】该装置能够明显区分不同质量浓度氨气,稳态阶段的主成分1值超过90%。KNN与SVm算法稳态阶段平均准确率超过97%,暂态阶段平均准确率68%,KNN与SVm平均分类准确率为68%。【结论】该多传感器阵列检测系统不需要等待传感器进入稳态阶段便可以读取数据,有助于农田环境中氨气快速和连续检测。

关键词：多传感器阵列挥发氨机器学习农田稳态相

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Deep Learning-based Environmental Sound Classification Using Feature Fusion and Data Enhancement

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Computers, materials & Continua 2023年第1期74卷 1069-1091页

作者： Rashid jahangir muhammad Asif Nauman Roobaea Alroobaea Jasem Almotiri muhammad mohsin malik Sabah m.Alzahrani Department of Computer Science COMSATS University IslamabadVehari CampusPakistan Department of Computer Science University of Engineering and Technology LahorePakistan Department of Computer Science College of Computers and Information TechnologyTaif UniversityTaif21974Saudi Arabia

Environmental sound classification(ESC)involves the process of distinguishing an audio stream associated with numerous environmental *** common aspects such as the framework difference,overlapping of different sound events,and the presence of various sound sources during recording make the ESC task much more complicated and *** research is to propose a deep learning model to improve the recognition rate of environmental sounds and reduce the model training time under limited computation *** this research,the performance of transformer and convolutional neural networks(CNN)are *** audio features,chromagram,mel-spectrogram,tonnetz,mel-Frequency Cepstral Coefficients(mFCCs),delta mFCCs,delta-delta mFCCs and spectral contrast,are extracted fromtheUrbanSound8K,ESC-50,and ESC-10,***,this research also employed three data enhancement methods,namely,white noise,pitch tuning,and time stretch to reduce the risk of overfitting issue due to the limited audio *** evaluation of various experiments demonstrates that the best performance was achieved by the proposed transformer model using seven audio features on enhanced *** UrbanSound8K,ESC-50,and ESC-10,the highest attained accuracies are 0.98,0.94,and 0.97 *** experimental results reveal that the proposed technique can achieve the best performance for ESC problems.

关键词： Environmental sound classification convolutional neural network deep learning transformer data augmentation

Reduced tillage with residue retention improves soil labile carbon pools and carbon lability and management indices in a seven-year trial with wheat-mung bean-rice rotation

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Pedosphere 2022年第6期32卷 916-927页

作者： Rafeza BEGUm mohammad m.R.jahangir mohammad JAHIRUDDIN mohammad Rafiqul ISLAm Shaikh m.BOKHTIAR Khandakar R.ISLAm Department of Soil Science Bangladesh Agricultural UniversityMymensingh 2202(Bangladesh) Soil Resource Development Institute Dhaka 1215(Bangladesh) South Asian Association for Regional Cooperation(SAARC)Agriculture Center Dhaka 1215(Bangladesh) The Ohio State University Columbus OH 43235(USA)

Soil total organic carbon(TOC)is a composite indicator of soil quality with implications for crop production and the regulation of soil ecosystem *** reports on the dynamics of TOC as a consequence of soil management practices in subtropical climatic conditions,where microbial carbon(C)loss is high,are very *** objective of our study was to evaluate the impact of seven years of continuous tillage and residue management on soil TOC dynamics(quantitative and qualitative)with respect to lability and stratification under an annual wheat-mung bean-rice cropping *** soil samples were collected at 0-15 and 15-30 cm depths from a three-replicate split-plot experiment with tillage treatment as the main plots and crop residue levels as the *** tillage treatments included conventional tillage(CT)and strip tillage(ST).Residue levels were high residue level(HR),30%of the plant height,and low residue level(LR),15%.In addition to TOC,soil samples were analyzed for particulate organic C(POC),permanganate oxidizable C(POXC),basal respiration(BR),specific maintenance respiration rate(qCO_(2)),microbial biomass C(mBC),potentially mineralizable C(PmC),and TOC lability and management *** ST treatment significantly increased the TOC and labile C pools at both depths compared with the CT treatment,with the effect being more pronounced in the surface *** HR treatment increased TOC and labile C pools compared with the LR *** ST+HR treatment showed significant increases in mBC,metabolic quotient(qR),C pool index(CPI),C lability index(CL_(I)),and C management index(CmI),indicating improved and efficient soil biological activities in such systems compared with the CT ***,the stratification values,a measure of soil quality improvement,for POC and mBC were>2,indicating improved soil quality in the ST+HR treatment compared with the CT *** ST+HR treatment not only significantly increased the contents o

关键词： basal respiration carbon management index carbon stratification particulate organic carbon permanganate oxidizable carbon total organic carbon

On the dynamics of nonlinear propagation and interaction of the modified KP solitons in multicomponent complex plasmas

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Journal of Ocean Engineering and Science 2022年第6期7卷 555-564页

作者： muhammad Shohaib W.masood R.jahangir m.Siddiq Sadah A.Alkhateeb S.A.El-Tantawy COmSATS University Islamabad Islamabad CampusPark RoadChak ShahzadIslamabad 44000Pakistan National Center for Physics(NCP) Quaid-i-Azam University CampusShahdrah Valley RoadIslamabad44000Pakistan mathematics Department Faculty of ScienceUniversity of JeddahJeddahSaudi Arabia Department of Physics Faculty of SciencePort Said UniversityPort Said 42521Egypt Research Center for Physics(RCP) Department of PhysicsFaculty of Science and ArtsAl-MikhwahAl-Baha UniversitySaudi Arabia

Dust-acoustic waves(DAWs)are analyzed in the small amplitude limit in a collisionless unmagnetized dusty plasma whose constituents are inertial dust grains,massless ions expressed by the generalized(r,q)distribution and inertialess maxwellian electrons using the fluid theory of *** modified Kadomtsev-Petviashvili(mKP)equation is derived at a critical plasma condition for which the quadratic nonlinearity *** propagation of single soliton and interaction of two solitons are analyzed for the mKP equation in the context of plasma physics by employing Hirota bilinear *** effects of the flatness parameter rand tail parameter q of the ions on the frequency of the DAWs are studied and the comparison with maxwellian and kappa distributions is *** the plasma parameters corresponding to the Saturn’s E-ring,the range of electric field amplitude for dust-acoustic solitary waves(DASWs)for different ion distributions is calculated and is shown to agree very well with the Cassini Wideband Receiver(WBR)*** interaction time of two DASWs for non-maxwellian ion distributions is estimated and shown to be fastest for the(r,q)distributed *** interesting feature of the interaction between compressive solitons with their rarefactive counterparts is also discussed in detail.

关键词： Non-maxwellian complex plasmas Dust-acoustic solitary waves Hirota bilinear method modified Kadomtsev-Petviashvili equation Solitons interaction

Establishment and Growth of Potato micro-Cuttings in Sand Trays

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American Journal of Plant Sciences 2012年第9期3卷 1219-1224页

作者： md. jahangir hossain mosammat Shamsun Nahar Plant Pathology Section Horticulture Research Center Bangladesh Agricultural Research Institute Joydebpur Bangladesh Research Wing Bangladesh Agricultural Research Institute Joydebpur Bangladesh

Two separate experiments were conducted to evaluate the success of the establishment and growth of micro-cuttings of potato (5 - 6 cm tall) in sand trays [38 cm (L) × 28 cm (W) × 7.5 cm (H) plastic trays] under controlled environment (22?C ± 2?C, 60 - 75 μmosm–1?s–1 light energy for 16 h daily). In the first experiment, micro-cuttings of potato cv. Diamant were planted at six populations (500, 600, 700, 800, 900 and 1000 cuttings per tray) in treated sand (sun dry, 1% formaldehyde, 0.2% Dithane m-45 and control). The mortality percentage of micro-cuttings was nil for sun dry sand while formaldehyde and dithane m-45 treated sand had 1% - 4% against 15% in the control with the highest population density. mortality of micro-cuttings in formaldehyde and dithane m-45 treated sand trays were found not to be related to pathogenic organism rather toxic effect of these two chemicals. micro-cuttings in Sun dry and control treatments showed better growth performance than these in chemically treated sand trays. In the second experiment, urea @ 1, 2 and 3 g per tray was applied as solid form after 15 days of planting the micro-cuttings and as liquid form @ 0.5, 1 and 2% solution sprayed in the micro-cuttings repeatedly after 15, 30, 45 and 60 days of planting. The micro-cuttings which received urea as solid state died within 2 - 3 days and 2% urea solution was also detrimental. Urea solution @ 0.5% found to be very effective for vegetative growth of micro-cuttings in sand trays. The control was also good for vegetative growth but at a slower rate.

关键词： Sand Tray Sun Dry Fungicides Urea Fertilizer Plant Population Growth Potato micro-Cuttings

Development and evaluation of local communities incentive programs for improving the traditional forest management:A case study of Northern Zagros forests,Iran

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Journal of Forestry Research 2014年第1期25卷 205-210页

作者： Jalal Henareh Khalyani manouchehr Namiranian S.m.Heshmatol Vaezin jahangir Feghhi Natural Resources Faculty University of Tehran

We examined the local community incentive programs to improve traditional forest management in three forested villages in Baneh city, Kurdistan province in the northern Zagros forests of western Iran. Zagros forests cover 6.07 million ha and support rich plant and animal diversity. Changes in local community social and economic sys-tems and the inefficiency of traditional forest management led to a criti-cal situation in the stability of forest regeneration in recent decades. Due to a shortage of productive and arable lands and resulting unemployment and poverty, people overexploited the Zagros forests. Outside interven-tion in traditional forest management creates conflicts between local peoples and forest management organizations. To achieve sustainable forest management, including forest resources conservation and im-provement of natural resource based livelihoods of communities, it is desirable to implement Forestry Incentive Programs （FIP） based on the important functions of forests. Detailed information on the so-cio-economics of communities, the effect of forests on local livelihoods, and lists of products extracted from the forest were obtained from a sur-vey of local communities though questionnaire, interview and observa-tion. We studied 276 households in three villages and completed 76 ques-tionnaires by householders in the quantitative analysis. Sampling was performed by simple random sampling （SRS）. The needs of rural com-munities, such as livestock husbandry, mainly arise from the characteris-tics and environmental features of villages. We identified the driving forces, pressures, status, impacts and responses （DPSIR） to design incen-tive programs, by DPSIR analysis and interaction analysis. Evaluation of local community benefits from forests showed that in order to improve forest management, 319 dollars per year would be needed by each family as an incentive in 2010 to prevent lopping and firewood collecting, the main causes of forest degradation.

关键词： Zagros forests traditional forest management forest protection Forestry Incentive Programs DPSIR analysis

Ameliorating Effects of TRIm67 on Ileum Inflammation and Barrier Function in Obese mice Induced by High Fat Diet

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Ameliorating Effects of TRIM67 on Ileum Inflammation and Bar...

作者： Asad jahangir 四川农业大学

学位级别：硕士

消化系统是宿主与其环境之间最大的屏障,它拥有一个完整的屏障框架,以保护宿主免受外部毒物,膳食抗原,微生物和其他可能有害的物质的侵害。这种保护是多种多样的,涉及不同的防御机制,例如粘膜层,不断代谢的上皮细胞和紧密连接(TJs)。如... 详细信息

消化系统是宿主与其环境之间最大的屏障,它拥有一个完整的屏障框架,以保护宿主免受外部毒物,膳食抗原,微生物和其他可能有害的物质的侵害。这种保护是多种多样的,涉及不同的防御机制,例如粘膜层,不断代谢的上皮细胞和紧密连接(TJs)。如今,由于长期高脂肪饮食(HFD)引起的肥胖和肥胖相关的代谢疾病是世界上的重大问题。动物研究的证据表明,HFD诱导肠道生态失调,炎症反应,氧化应激和增加肠道通透性。肠道屏障系统调节宿主防御机制以保护宿主免受外部毒物的侵害,但HFD通过刺激促炎信号级联直接增加肠道通透性,并间接通过激活屏障破坏细胞因子增加肠道通透性。TRIm67基因是TRIm家族蛋白质的成员,TRIm家族蛋白参与细胞周期停滞、细胞凋亡、DNA修复和衰老等重要的细胞过程。据我们所知,没有研究阐明TRIm67在HFD诱导肥胖小鼠回肠中的保护作用。本研究的目的是揭示TRIm67对肥胖诱导小鼠回肠炎症、氧化应激和屏障功能的改善作用。在本研究中通过在野生型(WT)和敲除(KO)小鼠中使用HFD饮食14周成功构建肥胖模型。通过使用包括H&E,PAS和masson染色来观察回肠的组织形态学变化。通过荧光定量PCR(q PCR)和蛋白质免疫印迹检查TRIm67基因缺失对肥胖小鼠肠道炎症,抗氧化酶活性和肠道屏障功能的影响。主要实验结果如下。1.高脂肪饮食对TRIm67表达的影响及肥胖模型构建成功HFD喂养14周后,与对照(CTR)饮食喂养的小鼠相比,用HFD喂养的小鼠体重显着增加。HFD增加了WT和KO小鼠的血糖水平,而对照饮食喂养的KO小鼠的血糖水平没有增加,并且表明TRIm67对血糖没有显着影响。此外,与WT CTR饮食小鼠相比,用HFD喂养的WT小鼠中的TRIm67表达下调。***67缺失诱导肥胖小鼠回肠组织病理学损伤组织病理学观察表明,KO小鼠和HFD喂养小鼠表现出病理损伤,包括绒毛的缩短和变钝以及隐窝深度的减少。而且,用HFD喂养的KO小鼠的杯状细胞数量减少和轻度纤维化。***67的缺失加剧肥胖诱导回肠中的炎症反应TRIm67缺失加剧肥胖诱导小鼠回肠中的肠炎症反应。包括TNF-α,IL-6,IL-1β和IL-2在内的炎性细胞因子的分析表明,与WT CTR组相比,KO CTR组中这些细胞因子的m RNA表达高。此外,与CTR组相比,HFD组(WT和KO)的m RNA表达量高。与WT HFD小鼠相比,KO HFD小鼠的IL-1β和IL-2m RNA表达上调。Western印迹(WB)结果显示KO HFD小鼠中TNF-α,IL-6和IL-1的蛋白表达量增加;与CTR组相比,HFD组小鼠抗炎细胞因子(IL-4和IL10)的m RNA表达受到抑制,IL-10和IL-4的蛋白表达水平表明,与所有其他组相比,KO HFD组的表达最低。***67缺失加剧肥胖小鼠回肠的屏障破坏本研究发现,用HFD喂养的WT和KO小鼠中claudin-1,occludin和ZO-1的m RNA表达下调,但KO CTR和KO HFD小鼠之间occludin的m RNA表达没有显着差异。此外,与WT CTR组相比,KO CTR饮食组中紧密连接蛋白的表达下调。WB结果表明,KO HFD组的相对蛋白表达水平比实验的所有其他组都受到抑制。***67缺失加剧肥胖小鼠回肠中的氧化应激与CTR组相比,HFD组中抗氧化酶SOD-1和SOD-2的m RNA表达降低。此外,HFD组中用试剂盒检测的SOD活力和GSH含量都显著下调,WT CTR组和KO CTR组的SOD活力没有显着差异,而KO CTR组的GSH含量与WT CTR组相比显著下降。总之,我们的数据提供了关于TRIm67在肥胖小鼠回肠中的保护作用的重要见解。我们证明TRIm67可以防止肠道炎症,保持肠道完整性,并减少HFD喂养引起的氧化应激。此外,需要更多的分析和临床试验来阐明TRIm67作为保护标志物的机制,因为近年来肥胖和肥胖相关的代谢疾病逐渐增加,TRIm67可能是有价值的治疗靶标。

关键词：高脂肪饮食 TRIm67 回肠炎症紧密连接氧化应激

Pilot Assignment Approach for Pilot Contamination mitigation in multi-Cell massive mImO System

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Pilot Assignment Approach for Pilot Contamination Mitigation...

作者： jahangir Khan 华南理工大学

学位级别：硕士

移动数据流量的快速增长对第五代(fifth-generation,5G)蜂窝网络来说是一个巨大的挑战。根据现有统计,2014年数据流量增长了69%,自2000年以来增长了30倍。据预测,未来几十年,这一需求仍将增加。然而,当前的蜂窝网络无法支持如此高的数... 详细信息

移动数据流量的快速增长对第五代(fifth-generation,5G)蜂窝网络来说是一个巨大的挑战。根据现有统计,2014年数据流量增长了69%,自2000年以来增长了30倍。据预测,未来几十年,这一需求仍将增加。然而,当前的蜂窝网络无法支持如此高的数据速率和频谱效率。为了满足对高数据速率和频谱效率的需求,时分双工(Time Division Duplex,TDD)大规模多输入多输出(massive multiple-Input multiple-Output,m mImO)系统被认为具有广阔的前景,它在基站(Base Stations,BS)使用大量天线来支持大规模用户(user,UE)。然而,TDD模式受到导频污染(Pilot Contamination,PC)的高度影响,这是由于在不同小区的用户之间使用相同的导频序列造成的。因此,PC是大规模mImO中的一个关键问题,它会显著降低系统性能,需要解决。在本论文中,我们提出了一种新的导频分配方案“超着色图导频分配(HCPA)来抑制PC并提高系统的频谱效率(Spectral Efficiency,SE)。根据这种HCPA方法,候选UE基于其信干噪比(Signal-to-Interference-Noise Ratio,SINR)分为两个区域,即小区中心区域和小区边缘区域。此外,为了限制最小上行链路速率,本文提出了具有超边的干扰关系图,利用图着色方法分配导频。仿真结果表明,该算法可以有效地降低PC,提高系统的和速率。此外,与传统的导频分配技术相比,该方法可以在较大的信噪比范围内保持较低的均方误差和归一化均方误差(mean Squared Error,mSE),更高的数据速率和更好的SE。

关键词：小区间干扰时分双工大规模mImO 信道状态信息导频分配信干噪比导频污染