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TaNRT2.1-6B is a dual-affinity nitrate transporter contributing to nitrogen uptake in bread wheat under both nitrogen deficiency and sufficiency

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The Crop Journal 2022年第4期10卷 993-1005页

作者： Mengjiao Li Tian Wang Hui Zhang Shuo Liu Wenhu Li Salah F.Abou Elwafa Hui Tian Key Laboratory of Plant Nutrition and Agri-environment in Northwest China Ministry of Agriculture and Rural AffairsCollege of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100ShaanxiChina Agronomy Department Faculty of AgricultureAssiut UniversityAssiut 71526Egypt

Multiple nitrate transporter(NRT)genes exist in the genome of bread wheat,and it is of great importance to identify the elite NRT genes for N-efficient wheat cultivar breeding.A candidate gene association study(CGAS)of six N use efficiency(NUE)related traits(grain N concentration(GNC),straw N concentration(SNC),grain yield(GY),grain N accumulation(GNA),shoot total N accumulation(STN)and N harvest index(NHI))was performed based on SNPs in 46 NRT2 genes using a panel composed of 286 wheat *** identified TaNRT2.1-6B as an elite NRT gene that is significantly associated with four(NHI,SNC,GNA and GY)of the six NUE-related traits ***2.1-6B is located on the plasma membrane and acts as a dual-affinity *** overexpression of TaNRT2.1-6B increased the N influx and root growth of wheat,whereas gene silence lines resulted in the opposite *** overexpression of TaNRT2.1-6B also improved GY and N accumulation of wheat under either limited or sufficient N *** data provide the TaNRT2.1-6B gene and the two associated SNP markers as promising powerful tools for breeding wheat cultivars with high N uptake ability and NUE.

关键词： Candidate gene association study Wheat TaNRT2.1-6B Dual-affinity transporter Nitrogen use efficiency

Orientation on the Mechanistics of Electron-Transfer on Oxidation of Chondroitin-4-Sulfate as Sustainable Sulfated Polysaccharide by Permanganate Ion in Aqueous Perchlorate Solutions

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Journal of Renewable Materials 2020年第2期8卷 205-218页

作者： Refat Hassan Hideo Takagi Samia Ibrahim Department of Chemistry Faculty of ScienceAssiut UniversityAssiut71516Egypt Department of Chemistry School of ScienceResearch Center of Materials ScienceNagoya464-01Japan Department of Chemistry Faculty of ScienceNew Valley UniversityEl-Kharga72511New ValleyEgypt

A spectrophotometric investigation of oxidation of chondroitin-4-sulfate(CS)as a sustainable and biodegradable sulfated macromolecule by oxyanion permanganate ion as multi-equivalent oxidant in acid perchlorate solutions at a constant ionic strength of 2.0 mol dm^(-3)has been *** experimental results on the influence of the concentration of the reactants the reaction rates revealed first-order dependence in MnO^(-)_(4),fractional second-order in[CS]and fractional first-order with respect to the hydrogen ion *** hydrogen acid concentration dependence of the rate constants indicated that the oxidation rates were increased with increasing the acid concentration which means that the oxidation reaction is of acid-catalyzed *** oxidation of all other polysaccharides by this oxidant in acidic solutions indicated that the oxidation processes were proceeding throughout two distinct *** first stage was relatively slow,followed by a more fast reaction in the second *** addition of Mn^(2+)and F^(-)ions to the reaction mixtures indicated that the Mn^(3+)and/or Mn^(4+)as the reduced forms of permanganate were the reactive species in the second fast ***,neither formation of Mn^(3+)and/or Mn^(4+)transient species nor presence of two stages in the oxidation reaction were detected in the oxidation process,and this result was found to be on contrary to that observed for oxidation of all other polysaccharides by this *** of 1:2 coordination biopolymer intermediate complexes prior to the rate-determining step was revealed,*** of the oxidation product revealed the formation of keto-acid as derivative precursor of CS *** product was identified by formation of 2,4-dinitrophenyhydrazone and dioxime as wells as by the bands at frequencies 3430(OH of COOH group);1760-1730 cm^(-1)(broad)for C=O of diketone;1639 cm^(-1)ofν_(as),OCO;1418 cm^(-1)ofν_(s)OCO and 1338 cm^(-1)of C-O-C,respectively,in the

关键词： Chondroitin-4-sulfate permanganate oxidation electron-transfer kinetics mechanisms

Bacterial and fungal endophthalmitis in Upper Egypt:related species and risk factors

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Asian Pacific Journal of Tropical Biomedicine 2012年第8期2卷 655-659页

作者： AA Gharamah AM Moharram MA Ismail AK AL-Hussaini School of Biological Sciences Universiti Sains Malaysia Department of Botany Faculty of SciencesAssiut University Department of Ophthalmology Faculty of MedicineAssiut University

Objective:To study risk factors,contributing factors of bacterial and fungal endophthalmitis in Upper Egypt,test the isolated species sensitive to some therapeutic agents,and to investigate the air-borne bacteria and fungi in opthalmology operating ***:Thirty one cases of endophthalmitis were clinically diagnosed and microbiologically *** air-borne bacteria and fungi inside four air-conditioned operating rooms in the Ophthalmology Department at assiut university Hospitals were also *** isolated microbes from endophthalmitis cases were tested for their ability to produce some extracellular enzymes including protease,lipase,urease,phosphatase and *** the ability of 5 fungal isolates from endophthalmitis origin to produce mycotoxins and their sensitivity to some therapeutic agents were ***:Results showed that bacteria and fungi were responsible for infection in 10 and 6 cases of endophthalmitis,respectively and only 2 cases produced a mixture of bacteria and *** was the most prevalent risk factor of endophthalmitis where 58.1%of the 31 cases were due to *** ophthalmology operating rooms,different bacterial and fungal species were isolated.8 bacterial and 5 fungal isolates showed their ability to produce enzymes while only 3 fungal isolates were able to produce *** showed the highest effect against most isolates in ***:The ability of bacterial and fungal isolates to produce extracellular enzymes and mycotoxins may be aid in the invasion and destruction of eye tissues. Microbial contamination of operating rooms with air-borne bacteria and fungi in the present work may be a source of postoperative endophthalmitis.

关键词： Bacterial Fungal Endophthalmitis Upper Egypt Risk factors Trauma Ophthalmic surgery

A New Trinortriterpenoid from Cleome chrysantha

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Chinese Chemical Letters 1998年第12期9卷 0-0页

作者： Ye Gao CHEN Guo Wei QIN (Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai 200031)Arafa I. HAMED (Faculty of Science, South Valley university, Aswan 81528, Egypt)Nasra EL-EMARY (Faculty of Pharmacy, assiut university, assiut Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai 200031 China Faculty of Science South Valley University Aswan 81528 Egypt Faculty of Pharmacy Assiut University Assiut 71526 Egypt Department of Chemistry University of Hong Kong Hong Kong Hong Kong

A new trinortriterpenoid, 1-epibrachycarpone, was isolated from the aerial parts ofCleome chrysantha. Its stfucture was elucidated by spectral and X-ray crystallographic studies.

关键词： Cleome chrysantha capparidaceae trinortriterpene 1-epibrachycarpone

Genesis of nanocrystalline Ho_2O_3 via thermal decomposition of holmium acetate: Structure evolution and electrical conductivity properties

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Journal of Rare Earths 2019年第2期37卷 185-192页

作者： Bahaa M.Abu-Zied Abdullah M.Asiri Center of Excellence for Advanced Materials Research (CEAMR) King Abdulaziz University Chemistry Department Faculty of Science King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This study focuses on the preparation of nanostructured holmium oxide via the decomposition of holmium acetate precursor utilizing the non-isothermal strategy. Thermogravimetric analysis(TGA) was used to follow up the various thermal events involved in the decomposition process. Dehydration completes approximately at 150℃, which is followed by the decomposition of the anhydrous acetate leading to the formation of holmium oxide. Based on the TGA results the acetate precursor was heated non-isothermally at the temperature range of 150 e700℃. The obtained solids were characterized using powder X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), Fourier transform infrared spectroscopy(FT-IR), field-emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM). It is found that nanocrystalline Ho_2 O_3 starts to form at 500℃ and presents the only phase detected at the 500 e700℃ range. The electrical conductivity of the solids that form at the temperature range of 300 e700℃ was investigated. The obtained values were correlated with the observed structural modifications accompanying the heat treatment. The electrical conductivity of the Ho_2 O_3 samples prepared at 500, 600 and 700℃ reaches the values of 1.92 × 10^(-7), 1.61 × 10^(-7) and 8.33 × 10^(-8) Ω^(-1)cm^(-1) at a measuring temperature of 500℃, respectively. These values are potentially advantageous for high-resistivity devices.

关键词： Nanocrystalline Ho2O3 Thermal decomposition Ho2O3 Holmium oxide Rare earth oxides Nanomaterials

Synthesis of Dy_2O_3 nanoparticles via hydroxide precipitation: effect of calcination temperature

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Journal of Rare Earths 2014年第3期32卷 259-264页

作者： Bahaa M.Abu-Zied Abdullah M.Asiri Chemistry Department Faculty of Science King Abdulaziz University Center of Excellence for Advanced Materials Research (CEAMR) King Abdulaziz University Chemistry Department Faculty of Science Assiut University

This work described the preparation of dysprosium oxide, Dy203, nanoparticles using the homogeneous precipitation method. Dy3＋ ions were precipitated using NaOH solution. The obtained product was filtered, dried, and then calcined for 1 h at the temperature range of 300-700 ℃ in static air. The calcination temperature of the Dy-precttrsor was chosen based on its decomposi- tion as indicated by the TGA analysis. The crystalline structure and surface morphology of the calcined solids were studied by X-ray diffraction （XRD）, field emission scanning electron microscopy （FE-SEM）, transmission electron microscopy （TEM） and X-ray pho- toelectron spectroscopy （XPS）. The obtained results revealed that Dy203 with crystallites size of 11-21 nm was formed at 500 ℃. Such value increased to 25-37 nm for the sample calcined at 700 ℃.

关键词： nanocrystalline dysprosium oxide Dy203 precipitation method Dy203 nanoparticles rare earths

Application of 3D Static Modelling in Reservoir Characterization:A Case Study from the Qishn Formation in Sharyoof Oil Field,Masila Basin,Yemen

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Acta Geologica Sinica(English Edition) 2022年第1期96卷 348-368页

作者： Emad A.ABDULLAH Ahmed ABDELMAKSOUD Musab A.HASSAN Department of Mineral Developing and Oil&Gas Engineering Academy of EngineeringPeople’s Friendship University of Russia(RUDN University)Moscow 117198Russia Department of Earth Sciences Khalifa UniversityAbu Dhabi 127788United Arab Emirates Department of Geology Faculty of ScienceAssiut UniversityAssiut 71516Egypt

Three-dimensional(3 D)static modelling techniques are applied to the characterization of the Qishn Formation(Fm.)in the Sharyoof oil field locating within the Masila basin,southeastern *** present study was initiated by the seismic structural interpretation,followed by building a 3 D structural framework,in addition to analysing well log data and from these,3 D facies and petrophysical models are *** the Sharyoof oil field,the Qishn *** depth values within the range of 400-780 m below sea level,with a general increase towards the SSE.A set of high dip angle normal faults with a general ENE-WSW trend dissect the *** strata are also folded as a main anticline with an axis that is parallel to the fault trend,formed as a result of basement *** to the facies models,the Qishn *** 43.83% limestone,21.53% shale,21.26% sandstone,13.21% siltstone and 0.17% *** Qishn Carbonates Member has low porosity values making it a potential seal for the underlying reservoirs whereas the Upper Qishn Clastics SI A and C have good reservoir quality and SIB has fair reservoir *** Upper Qishn Clastics S2 and S3 also have fair reservoir quality,while the Lower Qishn Clastics zone has good reservoir *** water saturation decreases towards the west and east and increases towards north and *** total original oil in-place(OOIP)of the Upper Qishn clastics is 106 million STB within the SI A,SIC and S2 *** of development wells is recommended in the eastern study area,where good trapping configuration is exhibited in addition to the presence of a potential seal(Upper Qishn Carbonates Member)and reservoir(Qishn Clastics Member)with high porosity and low water saturation.

关键词： upstream exploration petroleum basins seismic interpretation structural modelling well log analysis facies modelling petrophysical modelling Sayun-Masila basin

Compressive Sensing Approach in Multicarrier Sparsely Indexing Modulation Systems

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China Communications 2017年第11期14卷 151-166页

作者： Mostafa Salah Osama A.Omer Usama S.Mohamed Dept. of Electrical Engineering Sohag University Sohag Egypt Dept. of Electrical Engineering Aswan University Aswan 81542 Egypt Dept. of Electrical Engineering Assiut University Assiut Egypt Dept. of Electronics & Comm. Engineering Arab Academy for Science Technology and Maritime Transport Aswan

recently the indexed modulation(IM) technique in conjunction with the multi-carrier modulation gains an increasing attention. It conveys additional information on the subcarrier indices by activating specific subcarriers in the frequency domain besides the conventional amplitude-phase modulation of the activated subcarriers. Orthogonal frequency division multiplexing(OFDM) with IM(OFDM-IM) is deeply compared with the classical OFDM. It leads to an attractive trade-off between the spectral efficiency(SE) and the energy efficiency(EE). In this paper, the concept of the combinatorial modulation is introduced from a new point of view. The sparsity mapping is suggested intentionally to enable the compressive sensing(CS) concept in the data recovery process to provide further performance and EE enhancement without SE loss. Generating artificial data sparsity in the frequency domain along with naturally embedded channel sparsity in the time domain allows joint data recovery and channel estimation in a double sparsity framework. Based on simulation results, the performance of the proposed approach agrees with the predicted CS superiority even under low signal-to-noise ratio without channel coding. Moreover, the proposed sparsely indexed modulation system outperforms the conventional OFDM system and the OFDM-IM system in terms of error performance, peak-to-average power ratio(PAPR) and energy efficiency under the same spectral efficiency.

关键词： indexed modulation combinatorial modulation double sparsity critical sparsity sparsely indexed modulation OFDM-IM

Unique situation of hepatocellular carcinoma in Egypt:A review of epidemiology and control measures

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World Journal of Gastrointestinal Oncology 2021年第12期13卷 1919-1938页

作者： Reem Ezzat Mohamed Eltabbakh Mohamed El Kassas Internal Medicine Department Faculty of MedicineAssiut UniversityAssiut 71515Egypt Tropical Medicine Department Faculty of MedicineAin Shams UniversityCairo 11566Egypt Endemic Medicine Department Faculty of MedicineHelwan UniversityCairo 11795CairoEgypt

Hepatocellular carcinoma(HCC)is the sixth most common primary malignancy worldwide,and the third most common cause of death among cancers *** occurs in several pre-existing conditions,including hepatitis C,hepatitis B virus,and non-alcoholic *** used to be the country with the heaviest hepatitis C virus(HCV)*** relationship between HCV and HCC is an important research *** Egypt,HCC is a significant public health problem.A possible cause for the increasing rates of detection of HCC in Egypt is the mass screening program that was carried by the government for detecting and treating HCV.A multidisciplinary approach is now widely applied to HCC management in health centers all over *** treatment modalities are available in Egypt,with success rates comparable to global *** Egyptian health authorities have made the elimination of HCV from Egypt a special priority,and this approach should lead to a decrease in number of HCC cases in the near *** this article we review the current situation of HCC in Egypt,including epidemiological aspects,relevant risk factors for HCC development,strategies,and efforts established by health authorities for the screening and prevention of both HCV and HCC in *** highlight the different modalities for HCC treatment.

关键词： Hepatocellular carcinoma Liver cancer Hepatitis C virus Hepatitis B virus Screening Egypt