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Concentration–discharge patterns of weathering products from global rivers

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Acta Geochimica 2017年第3期36卷 405-409页

作者： Daniel E.Ibarra Seulgi Moon Jeremy K.Caves C.Page Chamberlain Kate maher Earth System Science Stanford University StanfordCA 94305-4216 USA Earth Planetary and Space Sciences University of California Los Angeles CA 90095-1567 USA Earth Science ETH Ziirich 8092 Zurich Switzerland Geological Sciences Stanford University StanfordCA 94305-2115 USA

Quantifying the functional relationships relating river discharge and weathering products places key constraints on the negative feedback between the silicate weathering and climate. In this study we analyze the concentration–discharge relationships of weathering products from global rivers using previously compiled time-series datasets for concentrations and discharge from global rivers. To analyze the nature of the covariation between specific discharge and concentrations, we use both a power law equation and a recently developed solute production equation. The solute production equation allows us to quantify weathering efficiency, or the resistance to dilution at high runoff, via the Damkohler coefficient. These results are also compared to those derived using average concentration–discharge *** the power law exponent and the Damkohler coefficient increase and asymptote as catchments exhibit increasingly chemostatic behavior, resulting in an inverse relationship between the two parameters. We also show that using thedistribution of average concentration–discharge pairs from global rivers, rather than fitting concentration–discharge relationships for each individual river, underestimates global median weathering efficiency by up to a factor of ～10. This study demonstrates the utility of long time-series sampling of global rivers to elucidate controlling processes needed to quantify patterns in global silicate weathering rates.

关键词： Concentration–discharge Rivers Silicate weathering Solutes

In-situ measurement on air-water flux of CH_(4),CO_(2) and their carbon stable isotope in lakes of northeast Tibetan Plateau

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Advances in Climate Change Research 2022年第2期13卷 279-289页

作者： Lei WANG Cun-De XIAO Zhi-Heng DU Damien T.maher Jing-Feng LIU Zhi-Qiang WEI State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Southern Cross Geoscience Southern Cross UniversityLismoreNSW 2480Australia College of Geography and Environmental Science Northwest Normal UniversityLanzhou 730070China Zhuhai Branch of State Key Laboratory of Earth Surface Process and Resource Ecology Beijing Normal UniversityZhuhai 519087China

Inland waters are important sources of greenhouse gases(GHGs)to the atmosphere that may partially offset the terrestrial carbon ***,GHG emissions from high altitude saline lakes on the Tibetan Plateau are currently poorly *** this study,we measured methane(CH_(4))and carbon dioxide(CO_(2))concentrations and their carbon stable isotope(δ13C),and calculated diffusive water-to-air fluxes from two saline high-altitude lakes,Qinghai Lake and Hala Lake,located in northeast Tibetan Plateau in October *** two lakes were mostly supersaturated in CH_(4)(89.8%-4623.9%sat)and acted as sources of CH_(4) to the ***,more than 96%investigated area of Qinghai Lake and all investigated area of Hala Lake was a sink of CO_(2).The average diffusive fluxes of CH_(4) and CO_(2) in the surface waters of Qinghai Lake were 34.51μmol m−2 d−1 and−1.29 mmol m−2 d−1,while diffusive fluxes of CH_(4) and CO_(2) in Hala Lake averaged 5.48μmol m−2 d−1 and−5.24 mmol m−2 d−1,***(Sal),fluorescent dissolved organic matter(fDOM),temperature(Temp)and dissolved oxygen(DO)are key factors for diffusive CH_(4) and CO_(2) flux in Qinghai Lake and Hala ***_(4) diffusive fluxes across water-air interface from Qinghai Lake and Hala Lake were found to be significantly lower than other freshwater lakes,likely due to their saline nature.A simple isotope mixing model(Miller-Tans plots)revealed a distinctly different isotopic source values of CO_(2) and CH_(4) in Qinghai Lake and Hala *** CH_(4) production pathway of Qinghai Lake was mainly by the acetate fermentation,while that of Hala Lake was mainly by the CO_(2) *** results show that the continuous measurement can help capture the spatial variability of GHGs fluxes in saline lakes.

关键词： Greenhouse gas Air-water flux Carbon stable isotope Tibetan Plateau Saline lakes

SOX9 in biliary atresia: New insight for fibrosis progression

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 154-162页

作者： Hanaa Ahmed El-Araby Magdy Anwar Saber Noha Mohamed Radwan Doha maher Taie Nermin Mohamed Adawy Ahmad Mohamed Sira Department of Pediatric Hepatology Gastroenterologyand NutritionNational Liver InstituteMenoufia University32511 Shebin El-koomMenoufiaEgypt Department of Pathology National Liver InstituteMenoufia University32511 Shebin El-koomMenoufiaEgypt

Background:Liver fibrosis is a hallmark determinant of morbidity in biliary atresia(BA)even in successfully operated *** factors for this rapid progression of fibrosis are not completely *** expression of the transcription factor SOX9 and hepatic progenitor cells(HPCs)proliferation have roles in fibrogenesis in cholestatic ***,they were not investigated sufficiently in *** aimed to delineate the relation of SOX9 and HPCs to fibrosis and its progression in ***:Forty-eight patients with BA who underwent an initial diagnostic liver biopsy(LB)and consequent intraoperative LB were recruited and compared to 28 cases with non-BA cholestasis that had an LB in their diagnostic *** fibrosis,tissue SOX9 and HPC expressions were studied in both BA and non-BA-cholestasis *** fibrosis,SOX9,and HPCs’dynamic changes in BA cases were *** of fibrosis and its progression to SOX9 and HPCs in BA was ***:SOX9 and HPCs in ductular reaction(DR)form were expressed in 100%of BA and their grades increased significantly in the second *** rapidly progressive fibrosis in BA,represented by fibrosis grade of the intraoperative LB,correlated significantly to SOX9-DR and HPC-DR at the diagnostic(r=0.420,P=0.003 and r=0.405,P=0.004,respectively)and the intraoperative(r=0.460,P=0.001 and r=0.467,P=0.001,respectively)*** the other hand,fibrosis,SOX9-DR,and HPC-DR were significantly lower in non-BA cases at a comparable age(P<0.001,P=0.006,and P=0.014,respectively).Conclusions:Fibrosis in BA is rapidly progressive within a short time and is significantly correlated to SOX9 and *** of targeting SOX9 and HPCs on fibrosis progression is warranted.

关键词： Biliary atresia Fibrosis Hepatic progenitor cells Immunohistochemistry Neonatal cholestasis SOX9

Students’Mathematical Reasoning,Communication,and Language Representations:A Video-Narrative Analysis

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ECNU Review of Education 2018年第3期1卷 1-22页

作者： Louise C.Wilkinson Alison L.Bailey Carolyn A.maher Psychology and Communication Sciences at Syracuse University University of California-Los Angeles Rutgers the State University of New Jersey

Purpose-Learning mathematics is a complex process,requiring many conceptual lenses and rich data sources to document and understand students’construction of *** purpose of this article is both to introduce a unique database on students’mathematical learning and to describe analytical techniques used to study students’growth of the knowledge of mathematics and ***/Approach/Methods-Our approach includes the following aspects:First,we describe a unique collection of video-taped recordings of longitudinal and cross-sectional studies of diverse,***,learning mathematics(Video Mosaic Collaborative,VMC).Second,we introduce our analytical methods,which utilize the database for collaborative study of students’*** methods include video-narrative analyses that display fine-grained examinations of interactions among students who are solving engaging problems that require them to reason mathematically and to represent their understandings with language and non-language *** analyses,referenced as VMCAnalytics,demonstrate the accessibility and flexibility of the database to study relationships among students’mathematics and language ***-The findings generated are illustrated by two examples demonstrating the accessibility and flexibility of the database to study relationships between mathematics and language learning(mathematics register).Originality/Value-The contribution of our work is illustrated by describing the rich database;employing a collaborative research approach;and signifying our understanding of relationships among students’mathematical and language learning.

关键词： Mathematics register communication mathematical understanding video-narratives academic language

Non-integer Order Control Scheme for Pressurized Water Reactor Core Power

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Computers, Materials & Continua 2022年第7期72卷 651-662页

作者： Ibrahim M.Mehedi maher H.AL-Sereihy Asmaa Ubaid Al-Saggaf Ubaid M.Al-Saggaf Department of Electrical and Computer Engineering(ECE) King Abdulaziz UniversityJeddah21589Saudi Arabia Center of Excellence in Intelligent Engineering Systems(CEIES) King Abdulaziz UniversityJeddah21589Saudi Arabia

Tracking load changes in a pressurized water reactor(PWR)with the help of an efficient core power control scheme in a nuclear power station is very *** reason is that it is challenging to maintain a stable core power according to the reference value within an acceptable tolerance for the safety of *** overcome the uncertainties,a non-integer-based fractional order control method is demonstrated to control the core power of *** available dynamic model of the reactor core is used in this *** power is controlled using a modified state feedback approach with a non-integer integral scheme through two different approximations,CRONE(Commande Robuste d’Ordre Non Entier,meaning Non-integer orderRobust Control)and FOMCON(non-integer order modeling and control).Simulation results are produced using MATLAB■*** non-integer results are compared with an integer order PI(Proportional Integral)algorithm to justify the effectiveness of the proposed ***-spacemodel Core power control Non-integer control Pressurized water reactor PI controller CRONE FOMCON.

关键词： Sate-space model core power control non-integer control pressurized water reactor PI controller CRONE FOMCON

Cook a Christmas Dinner for My Chinese Family

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国际人才交流 2011年第2期 58-59页

作者： Edwin maher

Hyers-Ulam-Rassias Stability for the Heat Equation

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Applied Mathematics 2013年第7期4卷 1001-1008页

作者： maher Nazmi Qarawani Department of Mathematics AlQuds Open University Salfit Palestine

In this paper we apply the Fourier transform to prove the Hyers-Ulam-Rassias stability for one dimensional heat equation on an infinite rod. Further, the paper investigates the stability of heat equation in ?with initial condition, in the sense of Hyers-Ulam-Rassias. We have also used Laplace transform to establish the modified Hyers-Ulam-Rassias stability of initial-boundary value problem for heat equation on a finite rod. Some illustrative examples are given.

关键词： Hyers-Ulam-Rassias Stability Heat Equation Fourier Transform Laplace Transform

Rational design of Pd-TiO_(2)/g-C_(3)N_(4) heterojunction with enhanced photocatalytic activity through interfacial charge transfer

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Clean Energy 2019年第1期3卷 59-68页

作者： Tayirjan Taylor Isimjan Shahid Rasul maher Nasser Aloufi Mohd Adnan Khan Ibrahim Khalid Alhowaish Toseef Ahmed Fundamental Catalysis SABIC-CRD at KAUSTThuwalSaudi Arabia King Abdullah University of Science and Technology(KAUST) Physical Science and Engineering DivisionThuwal23955-6900Saudi Arabia SABIC Technology Center RiyadhSaudi Arabia

A hybrid heterojunction-based photocatalyst is synthesized by an electrostatic self-assembly strategy including surface modification and controlled metal *** interfacial contact was made by mixing negatively charged anatase TiO_(2) nanoparticles with positively charged ***-light deposition of Pd nanoparticles largely on TiO_(2) was made possible due to the charge transfer from C_(3)N_(4)(excited by visible light)to the conduction band of TiO_(2) reducing Pd ions on contact with its *** order to further test the efficiency of this cascade of electron transfer across the conduction bands of the two semiconductors,photocatalytic H2 production from water was *** optimizing the ratio of the two semiconductors,increased H2 production rates were observed and attributed to enhanced charge *** were studied by a variety of techniques in order to probe into their properties and link them to *** reaction rate,under visible-light excitation,of the best sample showed an 8-fold enhancement when compared to that of Pd-C_(3)N_(4) in identical conditions and the highest apparent quantum yield of 31%was achieved by a 0.1% Pd/20%TiO_(2)/C_(3)N_(4) sample in a 420-to 443-nm range.

关键词： surface charge heterojunction photocatalyst electrostatic self-assembly hydrogen generation

Voice outcome measures after flexible endoscopic injection laryngoplasty

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2018年第2期4卷 130-134页

作者： Abdul-Latif Hamdan Marwan Rizk Elie Khalifee Georges Ziade maher Kasti Department of Otolaryngology and Head & Neck Surgery American University of Beirut-Medical Center Lebanon Department of Anesthesiology American University of Beirut-Medical Center Lebanon Department of Otolaryngology Head & Neck Surgery Rafic Hariri University Hospital Lebanon

Objective: To report voice outcome measures after injection laryngoplasty using the transnasal or transoral flexible endoscopic technique. Methods: A retrospective review of all patients who underwent flexible endoscopic injection laryngoplasty between June 2010 and August 2016 was carried out. Only those patients who had pre- and post-injection voice outcome measures recorded were included. Voice outcome measures recorded included perceptual voice evaluation using GRBAS, Voice Handicap Index-10 (VHI-10), maximum phonation time (MPT) and closed quotient (CQ) before and after treat-ment. Results: Forty-six patients were identified, of which 32 had pre- and post-injection voice outcome measures recorded. There were 19 males and 13 females. The mean age was 56.97 years (range 20—86 years) and the most common indication was unilateral vocal fold paralysis. Thirteen patients had a transnasal flexible endoscopic injection), while 19 patients were in-jected transorally. Following injection laryngoplasty, there was significant improvement in the mean grade of dysphonia (2.81 vs. 1.22, P < 0.01, roughness (2.44 vs. 1.34, P < 0.01), breathiness (2.72 vs. 1.13, P < 0.01), asthenia (2.78 vs. 1.06, P < 0.01), and strain (2.44 vs. 1.19, P < 0.01), MPT (3.85 s vs. 9.85 s, P < 0.01) and mean CQ (0.19 vs. 0.46, P < 0.01). There was also a decrease in the mean VHI-10 score (33.31 vs. 7.94, P < 0.01). Conclusion: s: Patients achieved significant improvement in both subjective and objective voice measures after flexible endoscopic injection laryngoplasty via the nasal or transoral route. Voice outcomes were comparable to those reported for other approaches. This tech-nique provides an alternative approach for the management of patients with vocal fold paral-ysis or glottal insufficiency.

关键词： Injection Laryngoplasty Transnasal Transoral Flexible endoscopic Vocal fold paralysis