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Soil enzyme Activities and Organic Matter Composition Affected by 26 Years of Continuous Cropping

Pedosphere 2016年第5期26卷 618-625页

作者： Fugen DOU alan L.WRIGHT Rao S.MYLAVARAPU JIANG Xianjun John e.MATOCHA Texas A&M AgriLife Research Center at Beaumont BeaumontTX 77713(USA) University of Florida Indian River Research&Education CenterFt.PierceFL 34945(USA) University of Florida Soil&Water Science Dept.GainesvilleFL 32611(USA) Southwest University College of Resources and EnvironmentChongqing(China) Texas A&M University Agricultural Research and Extension CenterCorpus ChristiTX 78406(USA)

The study was to determine the long-term effects of subtropical monoculture and rotational cropping systems and fertilization on soil enzyme activities and soil C, N, and P levels. Cropping systems included continuous sorghum(Sorghum bicolor L.), cotton(Gossypium hirsutum L.), corn(Zea mays L.), and cotton/sorghum rotations after 26 years of treatment imposition. Soil under continuous sorghum and continuous corn had 15% and 11%, respectively, greater C concentrations than soil under continuous *** C was 10% higher at 0–7.5 cm than at 7.5–15 cm. Total N followed similar trends with soil depth as organic C. Continuous sorghum had 19% higher total N than other crop species and rotations. With fertilization, continuous cotton had the highest total P at 0–7.5 cm and sorghum had the highest at 7.5–15 cm. Soil total P was 14% higher at 0–7.5 than at 7.5–15 cm, and fertilization increased 15% total P compared to unfertilized soil. Arylsulfatase, alkaline phosphatase, and β-d-glucosidase activity were the highest for sorghum and the lowest for cotton. Rotation increased enzyme activities compared to continuous cotton but not for continuous sorghum. Of all crop species and rotations, continuous cotton generally showed the lowest levels of organic matter and enzyme activities after 26 years. Fertilization significantly increased the yields for all cropping systems, but rotation had no significant effect on either sorghum or cotton lint yield compared to each crop grown in monoculture. Long-term cropping did not increase soil organic matter levels beyond short-term gains, indicating the difficulty in promoting C sequestration in subtropical soils.

关键词： C sequestration fertilization monoculture rotation subtropical soil

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How Could evidence-Based Reform Advance education?

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eCNU Review of education 2021年第1期4卷 7-24页

作者： Robert e.Slavin alan C.K.Cheung Tengteng Zhuang Johns Hopkins University The Chinese University of Hong Kong Beijing Normal University

Purpose:This article presents a definition and rationale for evidence-based reform in education,and a discussion of the current state of evidence-based research,focusing on China,the U.S.,and the ***/Approach/Methods:The article contrasts the state of educational research in the U.S.,the UK,and China,world leaders in evidence-based ***:The article suggests ways in which Chinese,U.S.,UK,and other scholars might improve the worldwide quality of evidence-based reform in *** indicator of this partnership is an agreement among the Chinese University of Hong Kong,Nanjing Normal University,and Johns Hopkins University to work together on Chinese and english versions of the website Best evidence in Brief and a collaboration between Johns Hopkins and the eCNU Review of education at east China Normal ***/Value:This article is the first to compare developments in evidence-based reform in education in China with parallel developments in the *** UK Building understanding of current evidence-based policies should help all countries learn how evidence can play a greater role in education policy and benefit many students.

关键词： evidence-based reform in education experiments international comparisons meta-analysis research designs

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Remote monitoring of implantable cardioverters defibrillators:a comparison of acceptance between octogenarians and younger patients

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Journal of Geriatric Cardiology 2020年第7期17卷 417-426页

作者： Iva Safarikova alan Bulava Premysl Hajek Faculty of Health and Social Sciences the University of South Bohemia in Ceske BudejoviceCeske BudejoviceCzech Republic Cardiac Center Department of CardiologyCeske Budejovice HospitalCeske BudejoviceCzech Republic Faculty of Medicine and Dentistry of Palacky University Olomouc OlomoucCzech Republic

Background Remote monitoring(RM)is increasingly employed for all types of cardiac implantable devices(CIeD).However,there are only limited data on the acceptance of RM by the *** aim of our study was to ascertain how octogenarians assess RM technologies compared to younger,presumably technically more literate patients,and what concerns or technical problems the system presents to both groups of *** The trial was designed as a descriptive,register-based single-center *** study population consisted of all consecutive patients≥80 years of age(group A,n=94)and all consecutive patients aged≤40 years(group B,n=71),who had undergone implantation of an implantable cardioverter-defibrillator(ICD)between the years of 2009 and 2018 and were using a Home Monitoring?(HM,Biotronik,Berlin,Germany)*** patients fulfilling entry criteria were approached with a request to participate in the *** A total of 85(90.4%)and 65(91.5%)valid surveys were obtained for groups A and B,***-two percent of patients in both groups(P=0.903)were satisfied with the limited number of planned ambulatory follow-ups(i.e.,once a year).All patients in both groups(100%)reported that they were satisfied with the HM system,and 97%and 94%of patients in Groups A and B,respectively,ranked it highly beneficial(P=0.68).A significant proportion of patients in both groups were completely unaware of any health-related benefits associated with the use of the HM system(42%in Group A vs.49%in Group B,P=0.4).Among the most frequently reported personal benefits of HM were a sense of safety and security and savings on travel expenses and time.5%and 9%of patients in Groups A and B,respectively,reported that usage of HM caused them some degree of psychological stress(P=0.27).Nearly all patients in both groups reported receiving information on HM from their doctor after ICD *** of Group A reported receiving information from a nurse either before or after

关键词： education Implantable electronic devices Remote monitoring The elderly

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efficiently adding mode multiplexing for cost-effective,high-capacity fiber links

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Advanced Photonics 2024年第1期6卷 8-9页

作者： alan e.Willner Huibin Zhou University of Southern California Los AngelesCaliforniaUnited States

For decades,a powerful approach to adding data capacity in an optical communication link has been to multiplex independent data-carrying channels and transmit them simultaneously along a fiber.^(1)For example,wavelength-division-multiplexing(WDM)was a key technology in the 1990s and early 2000s to dramatically increase aggregate capacity in a fiber by multiplexing beams of different wavelengths.^(2)For the past roughly 15 years,there has been great promise that space-division-multiplexing(SDM)may bring similar capacity enhancements to optical fiber communications.^(1–3)

关键词： fiber multiplexing adding

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Prograde and retrograde growth of monazite in migmatites:An example from the Nagercoil Block,southern India

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Geoscience Frontiers 2015年第3期6卷 373-387页

作者： Tim e.Johnson Chris Clark Richard J.M.Taylor M.Santosh alan S.Collins Department of Applied Geology The Institute for Geoscience Research(TIGeR)Curtin University School of the earth Sciences and Resources China University of Geosciences(Beijing) Tectonics Resources and Exploration(TRaX)Department of Earth SciencesUniversity of Adelaide

Data from a migmatised metapelite raft enclosed within charnockite provide quantitative constraints on the pressure-temperature-time （P-T-t） evolution of the Nagercoil Block at the southernmost tip of peninsular India. An inferred peak metamorphic assemblage of garnet, K-feldspar, sillimanite, plagioclase, magnetite, ilmenite, spinel and melt is consistent with peak metamorphic pressures of 6-8 kbar and temperatures in excess of 900 ℃. Subsequent growth of cordierite and biotite record high-temperature retrograde decompression to around 5 kbar and 800 ℃. SHRIMP U-Pb dating of magmatic zircon cores suggests that the sedimentary protoliths were in part derived from felsic igneous rocks with Palae- oproterozoic crystallisation ages. New growth of metamorphic zircon on the rims of detrital grains constrains the onset of melt crystallisation, and the minimum age of the metamorphic peak, to around 560 Ma. The data suggest two stages of monazite growth. The first generation of Ree-enriched monazite grew during partial melting along the prograde path at around 570 Ma via the incongruent breakdown of apatite. Relatively Ree-depleted rims, which have a pronounced negative europium anomaly, grew during melt crystallisation along the retrograde path at around 535 Ma. Our data show the rocks remained at suprasolidus temperatures for at least 35 million years and probably much longer, supporting a long-lived high-grade metamorphic history. The metamorphic conditions, timing and duration of the implied clockwise P-T-t path are similar to that previously established for other regions in peninsular India during the ediacaran to Cambrian assembly of that part of the Gondwanan supercontinent.

关键词： Monazire Migmatite Zircon Geochronology Phase equilibria modelling Gondwana

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Integrated sensing and communication in an optical fibre

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Light(Science & Applications) 2023年第5期12卷 729-742页

作者： Haijun He Lin Jiang Yan Pan Anlin Yi Xihua Zou Wei Pan alan e.Willner Xinyu Fan Zuyuan He Lianshan Yan Center for Information Photonics&Communications School of Information Science and TechnologySouthwest Jiaotong University611756 ChengduSichuanChina Peng Cheng Laboratory 518052 ShenzhenChina Optical Fiber Communications Laboratory University of Southern CaliforniaLos AngelesCA 90089USA State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University200240 ShanghaiChina

The integration of high-speed optical communication and distributed sensing could bring intelligent functionalities to ubiquitous optical fibre networks,such as urban structure imaging,ocean seismic detection,and safety monitoring of underground embedded *** work demonstrates a scheme of integrated sensing and communication in an optical fibre(ISAC-OF)using the same wavelength channel for simultaneous data transmission and distributed vibration *** scheme not only extends the intelligent functionality for optical fibre communication system,but also improves its transmission performance.A periodic linear frequency modulation(LFM)light is generated to act as the optical carrier and sensing probe in PAM4 signal transmission and phase-sensitive optical time-domain reflectometry(Φ-OTDR),*** a 24.5 km fibre transmission,the forward PAM4 signal and the carriercorrespondence Rayleigh backscattering signal are detected and *** results show that the integrated solution achieves better transmission performance(~1.3 dB improvement)and a larger launching power(7 dB enhancement)at a 56 Gbit/s bit rate compared to a conventional PAM4 signal ***,a 4m spatial resolution,4.32-nε/√Hz strain resolution,and over 21 kHz frequency response for the vibration sensing are *** proposed solution offers a new path to further explore the potential of existing or future fibre-optic networks by the convergence of data transmission and status *** addition,such a scheme of using shared spectrum in communication and distributed optical fibre sensing may be used to measure non-linear parameters in coherent optical communications,offering possible benefits for data transmission.

关键词： communication optical fibre

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Phase constitution of the noble metal thin-film complex solid solution system Ag-Ir-Pd-Pt-Ru in dependence of elemental compositions and annealing temperatures

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Nano Research 2022年第6期15卷 4827-4836页

作者： Bin Xiao Xiao Wang alan Savan Alfred Ludwig Materials Discovery and Interfaces Institute for MaterialsRuhr University Bochum44780 BochumGermany Zentrum für Grenzflächendominierte Höchstleistungswerkstoffe(ZGH) Ruhr University Bochum44780 BochumGermany

Multiple-principal element alloys hold great promise for multifunctional material discovery(e.g.,for novel electrocatalysts based on complex solid solutions)in a virtually unlimited compositional ***,the phase constitution of the noble metal system Ag-Ir-Pd-Pt-Ru was investigated over a large compositional range in the quinary composition space and for different annealing temperatures from 600 to 900°C using thin-film materials ***-dependent X-ray diffraction mapping of the asdeposited thin-film materials library indicates different phases being present across the composition space(face-centered cubic(fcc),hexagonal close packed(hcp)and mixed fcc+hcp),which are strongly dependent on the Ru *** general,low Ru contents promote the fcc phase,whereas high Ru contents favor the formation of an hcp solid-solution ***,a temperature-induced phase transformation study was carried out for a selected measurement area of fcc-Ag_(5)Ir_(8)Pd_(56)Pt_(8)Ru_(23).With increasing temperature,the initial fcc phase transforms to an intermediate C14-type Laves phase at 360°C,and then to hcp when the temperature reaches 510°*** formation and disappearance of the hexagonal Laves phase,which covers a wide temperature range,plays a crucial role of bridging the fcc to hcp phase *** obtained composition,phase and temperature data are transformed into phase maps which could be used to guide theoretical studies and lay a basis for tuning the functional properties of these materials.

关键词： noble metal high-entropy alloys phase transformation combinatorial synthesis and high-throughput characterization

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equal Sex Ratios of a Marine Green Alga, Bryopsis plumosa

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Journal of Integrative Plant Biology 2008年第6期50卷 648-652页

作者： Tatsuya Togashi Paul alan Cox Marine Biosystems Research Center Chiba University Institute for ethnomedicine Box 3464 Jackson Hole Wyoming 83001 USA Institute for ethnomedicine Box 3464 Jackson Hole

By finding some important culture conditions as below, we succeeded in experimentally controlling the whole life history of a dioecious marine green alga, Bryopsis plumosa （Hudson） C. Agardh. In this study, we focused on the primary and secondary sex ratios （i.e. at inception and maturity） using these culture techniques. Gametogenesis was induced by culturing haploid gametophytes with Provasoli＇s enriched seawater （PeS） medium under a 14：10 h light： dark cycle at 14 ℃. Formed zygotes grew into diploid sporophytes, which were cultured for 3 months with PeS medium under a 14：10 h light ： nbsp;dark cycle at 18℃. Then they were transferred into Schreiber medium and cultured under a 10：14 h light： dark cycle at 22℃. Within 1 week, zoosporogenesis was observed. Zoospores were released within a couple of days. each zoospore soon germinated and grew into a unisexual gametophyte. The primary sex ratio was examined in gametophytes that originated from a single sporophyte. The secondary sex ratio was studied in the field. Both were estimated as 1：1. Synchronized meiotic cell divisions might occur during zoosporogenesis dividing each sex-determining factor evenly among zoospores. Given the equal sex ratio at maturity, there seems to be no environmental factor that differentially affects the survival of male or female gametophytes in nature.

关键词： algal culture Bryopsis green algae life history sex ratio.

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Quality audit of colonoscopy reports amongst patients screened or surveilled for colorectal neoplasia

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World Journal of Gastroenterology 2012年第27期18卷 3551-3557页

作者： Daphnée Beaulieu alan Barkun Myriam Martel Division of Gastroenterology The McGill University Health CenterMcGill UniversityMontreal H3G 1A4Canada Clinical epidemiology the McGill University Health CenterMcGill UniversityMontreal H3G 1A4Canada

AIM： To complete a quality audit using recently pub- lished criteria from the Quality Assurance Task Group of the National Colorectal Cancer Roundtable. MeTHODS： Consecutive colonoscopy reports of patients at average/high risk screening, or with a prior col6rectal neoplasia （CRN） by endoscopists who perform 11 000 procedures yearly, using a commercial computerized endoscopic report generator. A separate institutional da- tabase providing pathological results. Required documen- tation included patient demographics, history, procedure indications, technical descriptions, colonoscopy findings, interventions, unplanned events, follow-up plans, and pathology results. Reports abstraction employed a stan- dardized glossary with 10% independent data validation. Sample size calculations determined the number of re- ports ***： Two hundreds and fifty patients （63.2± 10.5 years, female： 42.8%, average risk： 38.5%, per- sonal/family history of CRN： 43.3%/20.2%） were scoped in June 2009 by 8 gastroenterologists and 3 surgeons （mean practice： 17.1 ± 8.5 years）. Procedural indica- tion and informed consent were always documented. 14% provided a previous colonoscopy date （past polyp removal information in 25%, but insufficient in most to determine surveillance intervals appropriateness）. Most procedural indicators were recorded （exam date： 98.4%, medications： 99.2%, difficulty level： 98.8%, prep quality： 99.6%）. All reports noted extent of visualization （cecum： 94.4%, with landmarks noted in 78.8% - photodocu- mentation： 67.2%）. No procedural times were recorded. One hundred and eleven had polyps （44.4%） with ana- tomic location noted in 99.1%, size in 65.8%, morphol- ogy in 62.2%; removal was by cold biopsy in 25.2% （cold snare： 18%, snare cautery： 31.5%, unrecorded： 20.7%）, 84.7% were retrieved. Adenomas were noted in 24.8% （advanced adenomas： 7.6%, cancer： 0.4%） in this population with varying previous colonic investigations. CONCLUSION： This audit reveals lacking repo

关键词： Colonic-disorders endoscopy-general Oncol-ogy-clinical Colonoscopy endoscopic reporting system

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Technical challenges in tackling regulatory concerns for urban atmospheric nanoparticles

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Particuology 2011年第6期9卷 566-571页

作者： Prashant Kumar alan Robins Sotiris Vardoulakis Paul Quincey Division of Civil Chemical and Environmental EngineeringFaculty of Engineering and Physical Sciences(FEPS)University of Surrey environmental Flow(enFlo)Research Centre FEPSUniversity of Surrey Centre for Radiation Chemical and Environmental HazardsHealth Protection Agency Analytical Science Division National Physical Laboratory

Recent euro 5 and euro 6 vehicle emission standards are the first ever initiative to control particles on a number basis at the source. Related standards are also desirable for ambient nanoparticles （taken in this article to be those below 300 rim） to protect against possible adverse effects on public health and the environment. However, there are a number of technical challenges that need to be tackled before developing a regulatory framework for atmospheric nanoparticles. Some of the challenges derive from a lack of standardisation of the key measurement parameters, including sampling, necessary for robust evaluation of particle number concentrations, especially in the context of insufficient knowledge of the physicochemical characteristics of emerging sources （i.e. bio-fuel derived and manufactured nanoparti- cles）. Ideally, ambient concentrations of primary particles could be linked to primary particle emissions by use of nanoparticle dispersion models, and secondary nanoparticles using photochemical modeling tools. The limitations in these areas are discussed. Although there is inadequate information on the exact biological mechanism through which these particles cause harm, it is argued that this should not in itself delay the introduction of regulation. This article reviews the missing links between the existing knowledge of nanoparticle number concentrations and the advances required to tackle the technical challenges implied in developing regulations.

关键词： Airborne and manufactured nanoparticles Particle number concentrations Size distributions Street canyons Ultrafine particles Vehicle emissions

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