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Tigris, Euphrates, and Shatt Al-Arab river System: Historic and Modern Attempts to Manage and restore Iraq’s Lifeline

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Open Journal of Soil Science 2024年第1期14卷 28-63页

作者： Kenneth ray Olson david r. speidel College of Agricultural Consumer and Environmental Sciences University of Illinois Urbana USA US Army Iraq Mosul Iraq Foreign Agricultural Service Mahmudiyah Iraq Foreign Agricultural Service Washington D.C. USA

In Iraq, the principal rivers are the Tigris, Shatt Al-Arab and Euphrates. From their headwater sources in the mountains of eastern Türkiye, these rivers descend through valleys and gorges and flow into the uplands of Syria and northern and central alluvial plain of Iraq. The Euphrates and Tigris rivers confluence to form the Shatt Al-Arab river at Al-Qurnah which flows into the Persian Gulf. From sources in the Zagros Mountains other tributaries join the Tigris from the east. The Tigris and Euphrates rivers flow in a southeastern direction through the central plain and discharge into the Mesopotamian Marshes, which include permanent marshes, lakes, and riparian habitat. The rivers and their tributaries drain an area of 879,790 km2 which includes almost the entire area of Iraq as well as land in Syria, Türkiye, Kuwait and Iran. The region has historical importance as part of the Fertile Crescent region and where Mesopotamian civilization first emerged. The post war reconstruction efforts in the Yusifiyah township, an important food production region for Baghdad, illustrate the importance of these water resources. In addition, the advent of soil tunnels by Iraqi insurgents within the riverine corridors will make reconstruction of this resource more complex. The primary objectives of this study are to assess lessons learned, manage, and restore the Tigris, Euphrates, and Shatt Al-Arab river system lifeline in Iraq.

关键词： Mesopotamian Shatt Al-Arab Iraq Tigris Euphrates Baghdad Soil Tunnels Yusifiyah

Soil security and global food security

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Frontiers of Agricultural Science and Engineering 2024年第2期11卷 297-302页

作者： david r.MONTGOMErY Department of Earth and Space Sciences University of Washington townSeattleWA 98105USA

Over the course of the postglacial period has managed to add degrade a substantial portion of the world's potential agricultural land. The soil loss and degradation that has repeatedly impacted regional societies around the world resulted from agricultural practices that increased the physical loss of soil(erosion), reduced soil organic matter, changed p H(acidification) or salinity,and disrupted or altered communities of soil life. In the coming century, as continued soil degradation threatens global food security while the global population keeps rising it is imperative that farmers develop and adopt soilhealth building(regenerative) practices to solve a problem that has plagued societies throughout history. Growing evidence suggests that agricultural systems that combine cover crops, reduced tillage, and diverse crop rotations can reduce erosion, enhance soil health and rebuild soil organic matter to cultivate beneficial soil life and harvest both economic and environmental benefits. In the coming post-oil world, global food security would benefit from a global effort to promote soil restoration to help addresses the challenge of sustainably feeding the world, increase soil-based carbon sequestration,protect on-farm biodiversity and reduce off-farm water pollution. Because soil security sets a solid foundation for global food security, agricultural policies and subsidies should be reformed to encourage farmers to adopt regenerative,soil-building practices.

关键词： Agriculture soil security food security regenerative

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Hybrid LES/rANS Simulations of Compressible Flow in a Linear Cascade of Flat Blade Profiles

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Journal of Thermal Science 2024年第5期33卷 1839-1850页

作者： Jaromír PrIHODA Petr STrAKA david SIMUrDA Petr SIDLOF Jan LEPICOVSKY Institute of Thermomechanics of the Czech Academy of Sciences Dolejskova 1402/518200 Prague 5Czech Republic Aerospace research and Test Centre Beranovych 13019905 PragueCzech Republic Technical University of Liberec Faculty of MechatronicsStudentska 246117 Liberec 1Czech Republic

The paper reports on 3D numerical simulations of unsteady compressible airflow in a blade cascade consisting of flat profiles using a hybrid LES/rANS approach including a transition *** a first step towards simulation of blade flutter in turbomachinery,various incidence angle offsets of the middle blade were *** simulations were run for the flow regime characterized by outlet isentropic Mach number M_(is)=0.5and zero *** results of the LES/rANS simulations(pressure and Mach number distributions)were compared to a baseline rANS model,and to experimental data measured in a high-speed wind *** numerical results show that both methods overpredict flow separation taking place at the leading *** this regard,the hybrid LES/rANS method does not provide superior results compared to the traditional rANS ***,the LES/rANS results also capture vortex shedding from the blunt trailing *** frequency of the trailing edge vortex shedding in CFD simulations matches perfectly the spectral peak recorded during wind tunnel measurements.

关键词： numerical simulation blade cascade hybrid LES/rANS

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reflections on four decades of physical activity epidemiology

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Journal of Sport and Health Science 2024年第5期13卷 608-610页

作者： Barbara Sternfeld david r.Jacobs Jr. Division of research Kaiser Permanente Northern CaliforniaOaklandCA 94610USA Division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

In 1985,Public Health reports published a series of papers prepared for a workshop sponsored by the Centers for Disease Control and Prevention(CDC).1 Building on the seminal work of Jeremy Morris and ralph Paffenbarger Jr.,who were among the first to use epidemiological methods to study physical activity(PA),2,3 the workshop itself was the result of a growing scientific understanding of the importance of“physical fitness and exercise for improving the health of the public”.

关键词： semi workshop ralph

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Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.J.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

real-world clinical efficacy of tofacitinib in moderate-to-severe ulcerative colitis

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World Journal of Gastroenterology 2024年第34期30卷 3929-3931页

作者： Sara r Lopes Claudio Martins Madalena Teixeira david Tomás Department of Gastroenterology Unidade Local de Saúde da Arrábida-Hospital de São BernardoSetúbal 2910-446Portugal

Tofacitinib is an oral small-molecule Janus kinase(JAK)inhibitor that preferentially inhibits JAK1 and *** efficacy in inducing and maintaining remission in ulcerative colitis(UC)as well as its safety profile has been demonstrated in multicenter,randomized,double-blind,placebo-controlled ***,real-world studies evaluating the effectiveness and adverse effects of tofacitinib have been conducted,affirming its clinical efficacy in moderate-to-severe UC.

关键词： Ulcerative colitis Tofacitinib real-world studies Inflammatory bowel disease Janus kinase inhibitor

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science review 2024年第1期11卷 51-65页

作者： david A.T.Harper Palaeoecosystems Group Department of Earth SciencesDurham University

The Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. Two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. These symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas