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Improvement of Selected Morphological, Physiological, and Biochemical Parameters of Banana (Musa acuminata L.) Using Potassium Silicate under Drought Stress Condition Grown in vitro

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Phyton-International Journal of Experimental Botany 2023年第4期92卷 1019-1036页

作者： Hosny Abdel Aziz Mohamed Sharaf Magdy omar ahmed Abou El-Yazied Nada Ibrahim AlJwaizea Shaimaa Ismail Mohamed M.A.omar Khadiga Alharbi Amr Elkelish Moataz Tawfik Department of Horticulture Faculty of AgricultureAl-Azhar UniversityCairo11651Egypt Department of Biochemistry Faculty of AgricultureAl-Azhar UniversityCairo11651Egypt Department of Biochemistry and Molecular Biology College of Marine Life SciencesOcean University of ChinaQingdao266003China Department of Agricultural Botany Faculty of AgricultureAl-Azhar UniversityNasr CityCairo11751Egypt Department of Horticulture Faculty of AgricultureAin Shams UniversityCairo11566Egypt Department of Biology College of SciencePrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Biochemistry Faculty of AgricultureAin Shams UniversityCairo11566Egypt Biology Department College of ScienceImam Mohammad ibn Saud Islamic University(IMSIU)Riyadh11623Saudi Arabia Botany Department Faculty of ScienceSuez Canal UniversityIsmailia41522Egypt Botany Department Faculty of SciencePort Said UniversityPort Said42511Egypt

Drought stress has become more common in recent years as a result of climate change impacts on the production of banana crops and other fruit *** growth and productivity of Musa spp are severely impacted by the gradual degradation of water resources and the erratic distribution pattern of annual precipitation *** aim of the work includes increased drought tolerance in light of water scarcity in the world as a result of the bananas’being gluttonous for water *** investigation was carried out from 2019 to 2020 to study the effect of potassium silicate on morphological growth and biochemical parameters of Musa acuminata L under drought stress by *** a result,drought stress reduced the morphological characteristics such as shoots number,shoot length,roots number,and survival percentage and biochemical characteristics such as chlorophyll a,b,carotenoids,stomatal status,and *** proline content increased in the leaf of *** *** complemented with K2SiO3(2 to 6 mM)either individually or in combination with PEG led to an improvement in all morphological and biochemical *** activities of CAT,POD,and PPO enzymes increased significantly compared to ***,the lowest PPO,CAT,and POD activity were ***,K2SiO3 treatments under drought stress successfully enhanced the leaf stomatal *** results suggest that K2SiO3 can help to maintain plant integrity in the tested cultivar under drought stress.

关键词： Musa acuminata L potassium silicate photosynthetic pigments stomata enzymatic activity

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The Effect of Defects on the Mobility of HEMT Transistors Based on AIGaN/GaN

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Journal of Chemistry and Chemical Engineering 2014年第3期8卷 324-326页

作者： Meriem Hanzaz Said Fadlo ahmed Nouacry Abdelkader touhami Laboratory of Materials Physics Microelectronics Automatic and Thermic Faculty of Sciences Ain Chock Km8 University Hassan11 Casablanca 5366. Morocco

A phenomenological low-filed mobility model is developed to describe the dependence ot the carrier molgmty on me gate to source bias applied for AIGaN/GaN high electron mobility transistor. The results show excellent agreement with experimental data, when compared thereby proving the validity of the model. In the proposed work the temporal evolution of the mobility degradation shows a sharp decline in emission rates below 456 s-1. We also note a sharp decline for large defects densities.

关键词： AIGaN/GaN HEMT low-filed mobility model.

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Updated bone mineral density status in Saudi patients with inflammatory bowel disease

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World Journal of Gastroenterology 2020年第35期26卷 5343-5353页

作者： Mohammed Ewid Nawaf Al Mutiri Khalid Al omar Amal N Shamsan Awais A Rathore Nazmus Saquib Anas Salaas omar Al Sarraj Yaman Nasri ahmed Attal Abdulrahman Tawfiq Hossam Sherif Internal Medicine Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Internal Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt Gastroenterology Department King Fahad Specialist HospitalBuraidah 52366Al-QassimSaudi Arabia Epidemiology Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Medical students College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Critical Care Medicine Department College of MedicineSulaiman Al Rajhi UniversityBukairyah 51941Al-QassimSaudi Arabia Critical Care Medicine Department Faculty of MedicineCairo UniversityCairo 11562Egypt

BACKGROUND Little is known about inflammatory bowel disease(IBD)burden and its impact on bone mineral density(BMD)among adult patients in Saudi *** the best of our knowledge,our study is the only study to give an update about this health problem in adult Saudi patients with *** is a great risk factor for reduced BMD due to its associated chronic inflammation,malabsorption,weight loss and medication side ***,screening for reduced BMD among patients with IBD is of utmost importance to curb and control anticipated morbidity and mortality among those *** To assess the relationship between IBD and BMD in a sample of adult Saudi patients with *** Ninety adult patients with IBD-62 Crohn’s disease(CD)and 28 ulcerative colitis(UC)-were recruited from King Fahad Specialist Hospital gastroenterology clinics in Buraidah,*** enrolled patients were interviewed for their demographic information and for IBD-and BMD-related clinical *** patients had the necessary laboratory markers and dual-energy x-ray absorptiometry scans to evaluate their BMD *** were divided into two groups(CD and UC)to explore their clinical characteristics and possible risk factors for reduced *** The CD group was significantly more prone to osteopenia and osteoporosis compared to the UC group;44%of the CD patients had normal BMD,19%had osteopenia,and 37%had osteoporosis,while 78%of the UC patients had normal BMD,7%had osteopenia,and 25%had osteoporosis(P value<0.05).In the CD group,the lowest t-score showed a statistically significant correlation with body mass index(BMI)(r=0.45,P<0.001),lumbar z-score(r=0.77,P<0.05)and femur z-score(r=0.85,P<0.05).In the UC group,the lowest t-score showed only statistically significant correlation with the lumbar z-score(r=0.82,P<0.05)and femur z-score(r=0.80,P<0.05).The ROC-curve showed that low BMI could predict the lowest t-score in the CD group with the best cut-off value at≤23.43(m/kg2);area

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Bone mineral density Osteoporosis Fracture risk

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Robust Sliding Mode Controller for Rotary Electro-hydraulic Servo Systems

Robust Sliding Mode Controller for Rotary Electro-hydraulic ...

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作者：扎克（Zakarya Ali ahmed omar）东南大学

学位级别：硕士

控制技术的发展以及人们对机器人技术了解的增加,逐渐使机器人技术在人类活动的诸多领域中得到了应用。电机驱动、液压伺服驱动以及气压驱动等多种驱动方式被广泛运用于机器人的动力驱动中。其中,液压伺服驱动式机器人具有承载能力高、...

控制技术的发展以及人们对机器人技术了解的增加,逐渐使机器人技术在人类活动的诸多领域中得到了应用。电机驱动、液压伺服驱动以及气压驱动等多种驱动方式被广泛运用于机器人的动力驱动中。其中,液压伺服驱动式机器人具有承载能力高、适应性强、响应速度快等诸多优点,能够在很大程度上代替人类执行各种复杂的任务,具有广阔的应用前景。髋关节助力外骨骼机器人使用典型的弧形液压执行器驱动,用于帮助髋关节完成多种动作（例如跑步、爬升、弯腰和转身）所需的力量增强。这些电液伺服阀的流量压力特性和流量控制变化引起电液系统固有的非线性动态特性,使得电液伺服系统的控制精度和鲁棒性很难达到。因此,开发用于紧凑结构和大输出液压关节的高性能控制器一直是机器人领域的研究热点。滑模控制器（SMC）是一种应用广泛的非线性鲁棒控制器,它旨在减小或消除伺服系统参数的不确定性和髋关节外骨骼动力学非线性的影响。然而,大死区的存在会降低闭环系统的性能,导致系统不稳定而引发输出的不期望波动。此外,当这些高频欠阻尼振荡超过系统固有频率时,损坏致动器机械部件的风险增加。本文提出并将SMC与延迟补偿技术的结合,研究了两种方法:1)Smith Smith Predictor方案;2)时延估计（TDE）方案。这些延迟补偿技术与滑模控制相结合,消除了死区时间对系统性能的影响,同时,通过滑模控制克服了系统的非线性和固有参数不确定性。本论文有两个主要贡献:首先,设计一种鲁棒性滑模控制器,该控制器可计算系统的参数不确定性;其次,开发了延迟补偿技术以减轻死区时间或延迟时间对电液伺服系统闭环性能的影响。EHA系统是根据物理定律的理论建模的,它考虑了系统中非线性、不确定性和扰动的影响。在此基础上,提出了一种基于滑模控制律的鲁棒控制策略。针对具有非线性和模型不确定性的EHA系统,设计了相应的控制策略。SMC-SP方案中使用了典型电液伺服系统的ARX,SS和NLARX模型。实验结果证明了所提出控制器的鲁棒性。建议的SMC控制器迫使关节连杆跟踪所需路径,实现了平滑跟踪的同时并减少了稳态误差。然后,通过改变未建模的负载质量,测试了系统对参数不确定性的鲁棒性,并对结果进行了比较。最后,通过人工改变传输延迟周期来测试所提出的延迟补偿方案,比较了常规PID控制器和所提出方法的控制效果。结果表明,所提出的控制方法保证了执行器在大参数不确定性和死区/延迟时间下的鲁棒性和稳定性,能够比传统方法控制的系统获得了更好的跟踪性能。

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Bougainvillea spectabilis flowers extract protects against the rotenone-induced toxicity

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Asian Pacific Journal of Tropical Medicine 2017年第5期10卷 457-466页

作者： omar M.E.Abdel-Salam Eman R.Youness Nadia A.ahmed Sayed A.El-Toumy ahmed M.A.Souleman Nermeen Shaffie Dalia M.Abouelfadl Department of Toxicology and Narcotics National Research CentreCairoEgypt Department of Medical Biochemistry National Research CentreCairoEgypt Department of Chemistry of Tannins National Research CentreCairoEgypt Department of Phytochemistry and Plant Systematic National Research CentreCairoEgypt Department of Pathology National Research CentreCairoEgypt

Objective:To investigate the effect of two extracts of Bougainvillea spectabilis(B. spectabilis) flowers with yellow and pink/purple on brain oxidative stress and neuronal damage caused in rats by systemic rotenone injection. Methods:Rotenone 1.5 mg/kg was given three times per week alone or in combination with B. spectabilis flowers extracts(25 mg or 50 mg) via the subcutaneous route for 2 weeks. Brain concentrations of the lipid peroxidation marker malondialdehyde(MDA),reduced glutathione,nitric oxide(nitrite),the pro-inflammatory cytokine interleukin-1beta(Il-1β) as well as butyrylcholinesterase,and paraoxonase-1(PON-1) activities,were determined. Histopathology and caspase-3 immunohistochemistry were also performed. Results:Rotenone resulted in significant increases of brain MDA(the product of lipid peroxidation),and nitric oxide content along with decreased brain reduced glutathione. There were also marked and significant inhibition of brain PON-1 and BCh E activities and increased Il-1β in brain of rotenone-treated rats. B. spectabilis flowers extract itself resulted in brain oxidative stress increasing both lipid peroxidation and nitrite content whilst inhibiting PON-1 activity. The yellow flowers extract inhibited BCh E activity and increased brain Il-1β. When given to rotenone-treated rats,B. spectabilis extracts,however,decreased lipid peroxidation while their low administered doses increased brain GSH. Brain nitrite decreased by the pink extract but showed further increase by the yellow extract. Either extract,however,caused further inhibition of PON-1 activity while the yellow extract resulted in further inhibition of BChE activity. Histopathological studies indicated that both extracts protected against brain,liver and kidney damage caused by the toxicant. Conclusions:These data indicate that B. spectabilis flowers extracts exert protective effect against the toxic effects of rotenone on brain,liver and kidney. B. spectabilis flowers extracts decreased

关键词： Bougainvillea spectabilis Flowers Extract Rotenone Oxidative stress Parkinson’s disease

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Protective effect of Citrus reticulata peel extract against potassium dichromate-induced reproductive toxicity in rats

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Asian pacific Journal of Reproduction 2019年第6期8卷 267-275页

作者： Samir AE Bashandy omar A-H ahmed-Farid Enayat Aomara Sayed AEl-Toumy Josline YSalib Pharmacology Department National Research Centre33 El-Bohouth St.DokkiP.O.12622GizaCairoEgypt Physiology Department National Organization for Drug Control and ResearchCairoEgypt Pathology Department National Research CentreCairoEgypt Chemistry of Tannins Department National Research CentreCairoEgypt

Objective:To study the protective effect of Citrus reticulata peel extract against potassium dichromate-induced reproductive impairment in male Wistar ***:A total of 35 male Wistar rats were equally divided into 5 *** control group orally received an equivalent volume of saline(1 mL);group 2 was given potassium dichromate at 10 mg/kg/body weight(b.w.)orally for eight weeks;group 3 and 4 orally received Citrus reticulata peel extract at 200 and 400 mg/kg/***,followed by treatment with potassium *** 5 was administered with 400 mg/kg/*** reticulata peel extract *** parameters including oxidative stress(malondialdehyde,antioxidant enzymes),sex hormones(testosterone,luteinizing hormone,follicle-stimulating hormone)and inflammation indexes(tumor necrosis factor-alpha,inter leukin 6)were *** characteristics(sperm morphology,motility and count)were also ***:The decrease of male sex hormones concentration in plasma(testosterone,luteinizing hormone),testicular antioxidant parameters(reduced glutathione,catalase,superoxide dismutase,carnitine),sperm motility and sperm count induced by potassium dichromate was mitigated by Citrus reticulata peel ***,the peel extract alleviated the increase of sperm abnormalities,follicle-stimulating hormone,testicular malondialdehyde,tumor necrosis factor-alpha and nitric oxide levels caused by potassium *** sections of rats treated with the potassium dichromate were characterized by some histopathological changes as disorganization of spermatogonial cell layers and deformation of Leydig cells.A positive immune-reaction for p53 was observed in testicular cells of the rats treated with potassium *** extract of Citrus reticulata peel improved the testicular histology and decreased p53 positive immune-reaction in potassium dichromate administered ***:Citrus reticulata peel extract can alleviate the reproductive toxicity t

关键词： Citrus reticulatapeel extract Potassium dichromate Sperm Testicular function Oxidative stress Anti-inflammatory

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Monitoring and Change Detection along the Eastern Side of Qena Bend, Nile Valley, Egypt Using GIS and Remote Sensing

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Advances in Remote Sensing 2013年第3期2卷 276-281页

作者： ahmed omar Abd El-Aziz Senior of Geomatics-Al-Amar Consulting Group Cairo Egyp

This Article is set to track and monitor changes through spatial dependence of remote sensing data and GIS analysis, the suggested working method in this research is by sub pixel classification techniques. Change detection is a central task for land cover monitoring by remote sensing. It uses multi temporal image data sets in order to detect land cover changes from spectral discrepancies [1] (Rafael, et al.). It discusses the study perception of the situation in the past as well as the current and finally the future status of changes that land uses in Eastern Qena meander specifically in places of estuary floods, and the most important estuary leading to Qena, and whether these changes in land are used in direction of the mouth of the stream or not, especially that when it happened before, it caused destruction of both activities, urban & agricultural land. It will rely on Landsat images in years of (1972-2012), conduct analysis, different classifications integration with geographic information systems (GIS), and field as well as samples for the accuracy assessment.

关键词： Sub Pixel-Change Detection

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Spatial distribution,source apportionment,and associated risks of trace metals (As,Pb,Cr,Cd,and Hg) from a subtropical river,Gomti,Bangladesh

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International Journal of Sediment Research 2022年第1期37卷 83-96页

作者： Abu Sayeed Shafiuddin ahmed Mohammad Belal Hossain Saad Mohammad omar Faruque Babu Moshiur Rahman Jun Sun Mohammad Shafiqul Islam Sarker Department of Fisheries and Marine Science Noakhali Science and Technology University School of Engineering and Built Environment Griffith University College of Marine and Environmental Sciences Tianjin University of Science and Technology Forensic Science Laboratory Rapid Action Battalions Headquarters

Sediment samples from the Gomti River basin were investigated to determine and evaluate trace metal concentrations,their biological effect,and potential ecological and human health risks for adults and *** mean concentrations of trace metals were organized in the descending order of mercury(Hg)(0.08 mg/kg)>chromium (Cr)(0.06 mg/kg)>lead (Pb)(0.05 mg/kg)>arsenic (As)(0.02 mg/kg)>cadmium (Cd)(0.01 mg/kg).The current study illustrated that metals were attributed to the area from natural sources and different anthropogenic sources especially from ***,the concentration levels were lower than the sediment quality guidelines (SQGs) based on the effect-range classifications of threshold effect concentration (TEC) and probable effect concentration (PEC).Therefore,the concentration of the elements showed no adverse biological effects on aquatic *** evaluated potential ecological risk index also revealed the low toxicity to the aquatic ***,the applied sediment quality indices,geo-accumulation index (Igeo),contamination factor (CF),and contamination severity index (CSI) suggested that the contamination levels of the elements were in the acceptable range,and the contamination had not notably impacted on the sediment *** risk index (HI) concerning age groups was significantly less than the threshold limit of 1 indicating that the contamination had no non-carcinogenic risk *** total carcinogenic risk (TCR) was less than a risk value of 1×***,the current study suggests that immediate remediation is not required due to an absence of alarming conditions in the study *** monitoring of the attribution of the metal elements should be done for the betterment of human and environmental health.

关键词： Trace metals Biological effects Ecological risk Human health risk Gomti river Bangladesh

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Determination of delta-9-tetrahydrocannabinol content of cannabis seizures in Egypt

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Asian Pacific Journal of Tropical Medicine 2017年第3期10卷 291-294页

作者： ahmed M.A.Souleman Alaa El-Din M.Gaafar omar M.Abdel-Salam Shaimaa A.ElShebiney Department of Phytochemistry and Plant Systematic National Research CentreCairoEgypt Department of Photochemistry National Research CentreCairoEgypt Department of Toxicology and Narcotics National Research CentreCairoEgypt

Objective:To determine the delta-9-tetrahydrocannabinol(THC)content of cannabis seizures in ***:Unheated and heated extracts of cannabis seizures were prepared from the dried flowering tops and leaves(marijuana)or from the resin(hashish)and subjected to analysis using high performance liquid chromatography(HPLC).Results:The heated resin extract had the peak of THC in a relative ratio of 31.34%,while extracting the resin directly without heating contained only 18.34%of *** the other hand,marijuana showed minimum percentage of THC at 11.188% on heating and 9.55% without ***:These results indicate the high potency of the abused cannabis plant in the illicit Egyptian market.

关键词： Cannabis Hashish Marijuana THC High performance liquid chromatography

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Hydrocarbon-source correlation in the Obayied sub-basin， north Western Desert， Egypt: controls on generation of natural gas and light crude hydrocarbon blend

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Journal of Earth Science 2023年

作者： Mostafa Hassan Mahmoud Leila Mohammed ahmed Ghalib Issa Branimir ?egvi? omar Hegab Geology Departments， Faculty of Science-Mansoura University Texas Tech University， Department of Geosciences

Obayied sub-basin provides one-third of the annual natural gas production in the Egyptian Western Desert. The origin of the Obayied hydrocarbons are however poorly constrained. In this study， the molecular biomarkers of the Obayied hydrocarbon blend were studied to infer on their origin and generation mechanism. API values are in the range of (41.3°-53.7°) reflecting post-mature hydrocarbons. The molecular biomarkers suggest a generation of Obayied crude from clay-rich fluvio-deltaic source rocks. Age- and maturity-relevant biomarkers (e.g. Ts/Tm trisnorhopanes and methylphenanthrene indices) reflect a successive expulsion of the Obayied crudes from mature Jurassic rocks (> 1%Ro). Biological markers correlate perfectly with those of the Jurassic Khatatba shale and coal extracts attesting. Additionally， the Obayied gases are wet， thermogenic and have been derived from a mature (1.3%-2%Ro) type III kerogen. The studied gases display compositional characteristics of mixed coal- and oil-type gases， and were therefore derived via primary cracking of the Khatatba coal as well as secondary cracking of the light liquid crudes. The present study clarifies the controls on the geochemical processes responsible for the accumulation of liquid and gas hydrocarbon mix in the deep as well as shallow inverted rift basins of the north Western Desert， Egypt.

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