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Journal of Molecular Cell Biology 2022年第1期14卷 47-55页

作者： Qiansen Zhang Jie Fu sh.oying Zhang Peipei Guo sh.ie Liu Juwen sh.n Jiangtao Guo Huaiyu Yang sh.nghai Key Laboratory of Regulatory Biology Institute of Biomedical SciencesSchool of Life SciencesEast China Normal UniversityShanghai 200241China Department of Biophysics and Department of Pathology of Sir Run Run sh.w Hospital Zhejiang University School of MedicineHangzhou 310058China

Two-pore domain potassium (K2P) channels gate primarily within the selectivity filter, termed ‘C-type’ gating. Due to the lack of structural insights into the nonconductive (closed) state, ‘C-type’ gating mechanisms remain elusive. Here, molecular dynamics (MD) simulations on TREK-1, a K2P channel, revealed that M4 helix movements induce filter closing in a novel ‘deeper-down’ structure that represents a ‘C-type’ closed state. The ‘down’ structure does not represent the closed state as previously proposed and instead acts as an intermediate state in gating. The study identified the allosteric ‘seesaw’ mechanism of M4 helix movements in modulating filter closing. Finally, guided by this recognition of K2P gating mechanisms, MD simulations revealed that gain-of-function mutations and small-molecule activators activate TREK-1 by perturbing state transitions from open to closed states. Together, we reveal a ‘C-type’ closed state and provide mechanical insights into gating procedures and allosteric regulations for K2P channels.

关键词： K2P state selectivity filter C-type gating

Thermo-economic analysis of the performance of the combined system with evacuated tube collectors

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Clean Energy 2023年第2期7卷 242-252页

作者： Ghassan Fadhil Smaisim Salema K.Hadrawi Azher M.Abed Hasan sh.Majdi Ali sh.mel Department of Mechanical Engineering Faculty of EngineeringUniversity of Kufa54001Iraq Nanotechnology and Advanced Materials Research Unit(NAMRU) Faculty of EngineeringUniversity of Kufa54001Iraq Refrigeration and Air-conditioning Technical Engineering Department College of Technical EngineeringThe Islamic UniversityNajaf54001Iraq Computer Engineering Department Imam Reza UniversityMashhadIran Department of Air Conditioning and Refrigeration Al-Mustaqbal University CollegeBabylon51001Iraq Department of Chemical Engineering and Petroleum Industries Al-Mustaqbal University CollegeBabylon51001Iraq Department of Chemistry Ardebil BranchIslamic Azad UniversityArdebilIran

Using combined cooling,heat and power systems can be an appropriate substitute for preventing emissions of pollutants and excessive consumption of fossil *** renewable energy in these systems as a source of power generation can be an appropriate substitute for fossil-fuel-based ***,in this paper,cogeneration cooling,heat and power systems based on gas-fired internal combustion engines with a solar-thermal system with evacuated tube collectors have been modelled and thermo-economic analysis has been done to compare fossil-fuel-based *** required rate of heat to supply the hot water is 50 *** the studied system,the internal combustion engine produces electrical ***,the solar-thermal system with evacuated tube collectors and the gas-burning generator provide the thermal energy required by the studied building and the primary stimulus of the absorption chiller for *** this study,two different scenarios are conducted in states considering simultaneous production systems and regardless of this environmental and thermo-economic analysis *** results sh.wed that the efficiency of the studied system was 60% in summer and 56% in winter.

关键词： combined cooling,heat and power thermo-economic analysis evacuated tube collectors environmental analysis solar-thermal energy

Testicular Fine Needle Aspiration Cytology versus Open Biopsy in the Evaluation of Azoospermic Men

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Open Journal of Urology 2015年第9期5卷 133-141页

作者： Ala’a Al-Deen Al-Dabbagh Basim sh. Ahmed Department of Surgery College of Medicine Al-Mustansiriya University Baghdad Iraq Department of Pathology College of Medicine Al-Mustansiriya University Baghdad Iraq

Background: Male infertility is a common problem and needs a minimally invasive method to arrive at the appropriate diagnosis. Alternative to open testicular biopsy the fine needle aspiration cytology (FNAC) of the testis is being increasingly used?as a minimally invasive method of evaluating testicular function. Aim: To determine the causes of azoospermia and evaluate the efficacy of FNAC as compared to open testicular biopsy in evaluating azoosparmic men by correlating diagnosis from testis FNAC with biopsy histology. Patients and Methods: We prospectively studied 67 consecutive infertile patients who referred to andrology department of Al-Yarmouk Teaching hospital, Baghdad, Iraq between (January 2010-January 2014). All patients were azoospermic. They underwent bilateral testicular fine needle aspiration for cytological evaluation as well as bilateral testicular biopsy for histopathological correlation. Results: The morphological diagnosis revealed normal spermatogenesis in 12 patients (17.9%), hyposparmatogenesis in 4 (5.9%), spermatogenic arrest in 39 (58.2%), Sertoli cell only in 7 (10.4%), and complete tubular hyalinization in 5 patients (7.4%). Good correlation between the 2 methods was found in 120 (91.6%) testes which was identical in the right and left testis. Discrepancies between cytology and histology were mainly the result of insufficient and scanty smears. Conclusion: Testicular FNAC is a simple and minimally invasive alternative method to open testicular biopsy in the investigation and assessment of patients with azoospermia.

关键词： Azoospermia Testis FNA Biopsy Cytology Histology

高分散多壁碳纳米管增强铝基复合材料的制备(英文)

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新型炭材料 2012年第3期27卷 161-165页

作者： A. H. Javadi sh. Mirdamadi M. A. Faghihisani S. sh.khesi R. Soltani Department of Materials Engineering Science and Research Branch Islamic Azad University Tehran Iran Engineering Research Institute Tehran Iran

采用机械合金化技术制备高分散多壁碳纳米管(MWCNTs)-铝(Al)复合材料。将纯度99%的铝粉和质量分数2%的MWCNTs经超声和水平球磨处理使Al颗粒与MWCNTs间产生机械键合力。场发射SEM观察表明,MWCNTs分散在Al薄片的表面,随球磨时间的不同,颗... 详细信息

采用机械合金化技术制备高分散多壁碳纳米管(MWCNTs)-铝(Al)复合材料。将纯度99%的铝粉和质量分数2%的MWCNTs经超声和水平球磨处理使Al颗粒与MWCNTs间产生机械键合力。场发射SEM观察表明,MWCNTs分散在Al薄片的表面,随球磨时间的不同,颗粒大小和形貌各异。采用加压烧结手段将混合粉末加工成块体材料,其微观硬度测试表明,加入MWCNTs后Al基体的机械性能得到提高。

关键词：多壁碳纳米管金属基体复合材料球磨

Oscillation Properties of Third Order Neutral Delay Differential Equations

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Applied Mathematics 2016年第15期7卷 1780-1788页

作者： Elmetwally M. Elabbasy Osama Moaaz Ebtesam sh. Almehabresh Department of Mathematics Faculty of Science Mansoura University Mansoura Egypt Department of Mathematics Faculty of Education AL Asmarya Islamic University Zliten Libya

Oscillation criteria are establish.d for third-order neutral delay differential equations with deviating arguments. These criteria extend and generalize those results in the literature. Moreover, some illustrating exa... 详细信息

关键词： Oscillation Third Order Neutral Delay Differential Equations

Modelling and optimization of combined heat and power system in microgrid based on renewable energy

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Clean Energy 2023年第4期7卷 735-746页

作者： Ghassan F.Smaisim Azher M.Abed Salema K.Hadrawi Hasan sh.Majdi Ali sh.mel Department of Mechanical Engineering Faculty of EngineeringUniversity of Kufa54001Iraq Nanotechnology and Advanced Materials Research Unit(NAMRU) Faculty of EngineeringUniversity of Kufa54001Iraq Air Conditioning and Refrigeration Techniques Engineering Department Al-Mustaqbal University CollegeBabylon51001Iraq Refrigeration and Air-conditioning Technical Engineering Department College of Technical EngineeringThe Islamic UniversityNajafIraq Department of Chemical Engineering and Petroleum Industries Al-Mustaqbal University CollegeBabylon 51001Iraq Department of Chemistry Ardebil BranchIslamic Azad UniversityArdebilIran

Due to the sh.rt distance between the sources of production and consumption,microgrids(MGs)have received considerable attention because these systems involve fewer losses and waste less *** another advantage of MGs is that renewable energy sources can be widely used because these resources are not fully available and can provide a part of the required *** purpose of this research is to model the MG considering the production sources of microturbines,gas turbines and internal combustion *** energies such as wind turbines(WTs)and photovoltaic(PV)cells have been used to provide part of the required power and,because of the lack of access to renewable energy sources at all times,energy reserves such as batteries and fuel cells(FCs)have been *** power of the microturbine,gas turbine,internal combustion engine,FC and battery in this system is 162,150,90,100 and 225 kW,*** modelling the studied system,optimization was done using the imperialist competitive algorithm to minimize production costs and provide maximum thermal and electrical *** maximum production power for PVs is equal to 0.6860 MWh and at this time this value for WTs is equal to 0.3812 MWh,in which case the excess electricity produced will be sold to the grid.

关键词： microgrid energy management system optimization optimal power flow combined heat and power sustainable development

On Isoperimetric Inequalities of Riesz Potentials and Applications

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Applied Mathematics 2013年第7期4卷 1-4页

作者： Tynysbek sh. Kalmenov Ernazar Nysanov Bolys Sabitbek Institute of Mathematics and Mathematical Modeling Almaty Kazakhstan

In this article, we prove certain isoperimetric inequalities for eigenvalues of Riesz potentials and sh.w some applications of the results to a non-local boundary value problem of the Laplace operator.

关键词： Isoperimetric Inequalities Eigenvalues of the Laplacian Riesz Potentials

Bombyx Mori Chitosan Nanoparticles: Synthesis and Properties

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Open Journal of Organic Polymer Materials 2019年第4期9卷 63-73页

作者： R. Yu. Milush.va S. sh. Rash.dova Institute of Polymer Chemistry and Physics Academy of Sciences Tashkent Uzbekistan

A synthesis of nanochitosan from Bombyx mori chitosan with particle sizes of 20 - 100 nm was carried out. The antibacterial and immunological properties of synthesized nanochitosan were first studied. It was revealed that preparations based on nanochitosan have pronounced antibacterial activity, and are also able to significantly increase the immune response of the living system.

关键词： Antibacterial Activity Biodegradability Chitosan Nanoparticles

The Outcomes of Pregnancy with Congenital Heart Disease: An Integrative Literature Review

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Open Journal of Nursing 2020年第5期10卷 473-489页

作者： Hanan Al Obieat Inaam Khalaf Maan sh. Al Momani School of Nursing The University of Jordan Amman Jordan Royal Medical Services Queen Alia Heart Institute Amman Jordan

Purpose: The purpose of this review was to identify the sh.rt-term and long-term outcomes of pregnancy in women suffering from congenital heart disease (CHD). Methods: An integrative review is used to identify the pregnancy outcomes in women with CHD. Data search was between 2010 and 2020 using Google Scholar, Scopus, Web of Science, Science Direct, Pub Med, Medline, CINAHL, EBSCO, Cochrane, and EBSCO host. Sixteen articles met the eligibility criteria. Results: The sixteen reviewed articles utilized descriptive retrospective and prospective design. Themes were sh.rt-term outcomes that include;cardiac maternal and obstetric outcomes, and long-term outcomes. Conclusion: Previous uncertainty about the ability of CHD patients to successfully become pregnant and deliver safely has replaced by the recognition that a large number can have excellent outcomes. However, these patients do continue to have higher cardiac, obstetric, and fetal risks than the general population. This illuminates the importance of preconception counseling and risk assessment for women suffering from CHD regarding the expected maternal and fetal outcomes. Moreover, there is a need for providing accurate and appropriate education about pregnancy and delivery options.

关键词： Congenital Heart Disease Pregnancy Outcomes Adverse Events

Two-dimensional analysis of a negative differential conductance gate transistor as a THz emitter

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Plasma Science and Technology 2017年第4期19卷 15-22页

作者： sh.RAHMATALLAHPUR A ROSTAMI S KHORRAM Photonics and Nanocrystal Research Lab.(PNRL) Faculty of Electrical and Computer EngineeringUniversity of TabrizTabriz 51666-14761Iran Photonics Group Research Institute for Applied Physics and Astronomy(RIAPA)University of TabrizTabriz 51664-14761Iran

We investigate plasma modes in a transistor including a negative differential conductance in the gate. The analytical results sh.w that the plasma wave generation is substantially influenced by the lateral direction （width of the transistor）, gate leakage current and ＇viscosity. The injection from the gate （opposed to the gate leakage current） can improve the plasma oscillations and their amplitude with respect to ordinary transistors. We also estimate, which to our best knowledge has been derived for the first time, the total power emitted by the transistor and the emitted pattern which qualitatively gives reasonable agreement with the experimental data. The results sh.w that the radiated power depends on various parameters such as drift velocity, momentum relaxation time, gate leakage current and especially the lateral direction. A negative gate current enhances the power while the gate leakage current decreases the power.

关键词： terahertz emitter solid state plasma two-dimensional analysis negative differentialconductance