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放牧和刈割对内蒙古典型草原植物养分的不同影响

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Journal of Plant Ecology 2023年第1期16卷 25-36页

作者： Jiayue Liu Lu Li Lei Ji Yanlong Li Jiaojiao Liu frank Yonghong Li Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau and Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China collaborative Innovation center for Grassland Ecological Security Ministry of Education of ChinaHohhot 010021China National Agricultural Experimental Station for Soil Quality Institute of Grassland ResearchChinese Academy of Agricultural ScienceHohhot 010022China

放牧和刈割管理是天然草原的两种主要利用方式。放牧和刈割分别通过粪尿归还和养分移除的形式影响草原生态系统养分循环。植物养分对草原生态系统养分循环具有敏感的响应。然而,放牧和刈割管理在植物器官水平、种群和群落水平对植物养... 详细信息

放牧和刈割管理是天然草原的两种主要利用方式。放牧和刈割分别通过粪尿归还和养分移除的形式影响草原生态系统养分循环。植物养分对草原生态系统养分循环具有敏感的响应。然而,放牧和刈割管理在植物器官水平、种群和群落水平对植物养分具有怎样的影响,目前还缺乏准确的认知。我们在内蒙古半干旱草原地区通过野外控制实验探究持续放牧和轮牧以及低频率刈割和高频率刈割对草原生态系统的影响,并对不同处理下植物群落特征进行调查以及群落优势物种碳、氮和磷浓度进行测定。结果表明,(i)在持续放牧和轮牧下随放牧强度的增加,群落高度和地上现存量显著降低;每年一次刈割处理显著降低群落高度和地上现存量;(ii)在两种放牧制度下随放牧强度的增加,植物地上部分碳浓度显著降低,而氮、磷浓度则显著提高;不同刈割制度对植物地上部分碳、氮、磷浓度无显著影响;(iii)在两种放牧制度下随放牧强度的增加,植物群落碳、氮、磷库显著降低;不同刈割制度对植物群落碳、氮、磷库无显著影响;(iv)两种放牧下随放牧强度的增加,植物根系碳、氮、磷浓度无显著变化;两种刈割制度下植物根系碳、氮、磷浓度无显著变化,表明植物根系养分对外界干扰具有相对较高的稳定性和滞后性。本研究从多角度阐明了放牧和刈割管理对草原生态系统养分循环的影响。

关键词：放牧制度刈割制度植物地上养分植物根系养分典型草原

Electrical properties and microstructure formation of V/Al-based n-contacts on high Al mole fraction n-AlGaN layers

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Photonics Research 2020年第8期8卷 1381-1387页

作者： LUcA SULMONI frank MEHNKE ANNA MOGILATENKO MARTIN GUTTMANN TIM WERNIcKE MIcHAEL KNEISSL Institut für Festkorperphysik Technische Universitat Berlin10623 BerlinGermany Ferdinand-Braun-Institut Leibniz-Institut fur Höchstfrequenztechnik12489 BerlinGermany Institut für Physik Humboldt Universität zu Berlin12489 BerlinGermany

The electrical and structural properties of V/Al-based n-contacts on n‐AlxGa1−xN with an Al mole fraction x ranging from x=0.75 to x=0.95 are *** n-contacts are obtained up to x=0.75 with a contact resistivity of 5.7×10^−4Ω·cm^2 whereas for higher Al mole fraction the iv characteristics are *** electron microscopy reveals a thin crystalline AlN layer formed at the metal/semiconductor interface upon thermal *** analysis confirmed an Al enrichment at the *** interfacial nitride-based layer in n-contacts on n‐Al0.9Ga0.1N is partly amorphous and heavily contaminated by *** role and resulting limitations of Al in the metal stack for n-contacts on n-AlGaN with very high Al mole fraction are ***,ultraviolet c(UVc)LEDs grown on n‐Al0.87Ga0.13N and emitting at 232 nm are fabricated with an operating voltage of 7.3 V and an emission power of 120μW at 20 mA in cw operation.

关键词： AlGaN fraction properties

A Possible Alternative to the Accelerating Universe iv

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Journal of Modern Physics 2017年第4期8卷 622-635页

作者： frank R. Tangherlini P.O. Box 928211 San Diego CA 92192 USA

This work briefly reviews and extends the author’s three previous works (2015), Journal of Modern Physics, 6, 78-87, and 1360-1370;(2016), 7, 1829-1844 that propose as an alternative to the accelerating ΛcDM universe, the decelerating Einstein de Sitter (EdS) universe, in which dark energy is a different phase of dark matter located only in intergalactic space (IGS), and that instead of a negative pressure, it has an index of refraction n≈1.50, and hence a reduced speed of light c / n through it. This allows the EdS universe to expand the extra distance necessary to obtain the diminished brightness of the Type Ia supernovae. In view of the recent suggestion that the universe is not accelerating, but possibly expanding uniformly, a table is given comparing both the accelerating and uniformly expanding universes with the EdS universe supplemented by the reduced speed of light. It is shown that fitting the uniformly expanding universe leads to a smaller value of n, and hence too short an age for the EdS universe, unlike the case with fitting the accelerating universe. The main result is that the proposed reduced speed of light in the IGS predicts discordant redshifts. It is shown that the current explanation of “accidental superposition,” is most likely insufficient to explain the number of observations, and that the present proposal could make up the difference. It can be tested astronomically, as illustrated in a figure.

关键词： Dark Energy Speed of Light Expansion comparisons Discordant Redshifts

Development and quality of bovine embryos produced in vitro using growth factor supplemented serum-free system

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Open Journal of Animal Sciences 2011年第3期1卷 97-105页

作者： Arindam Dhali Vahida M. Anchamparuthy Steve P. Butler Isis K. Mullarky Ronald E. Pearson frank c. Gwazdauskas 不详

The influence of a growth factor supplemented serum-free system on the development, gene expression, and cryotolerance of in vitro pro- duced bovine embryos was investigated. To assess the embryo development and gene ex- pression in blastocysts, abattoir-derived oo- cytes (obtained from 3 - 10 or cles) were matured and fertilized in serum-free media and cultured in synthetic oviductal fluid sup- plemented with fetal bovine serum (FBS, 4%), epidermal growth factor (EGF, 10 ng/mL), insulin like growth factor-1 (IGF-1, 100 ng/mL), stem cell factor (ScF, 50 ng/mL) or combinations of the growth factors. Expressions of selected gene transcripts were relatively quantified in the d 8 blastocysts. To assess the cryotolerance, d 4 morulae (derived from 3 - 10 mm follicles and cultured with the supplementation of FBS or combinations of the growth factors) were vitri- fied, thawed and cultured (with respective sup- plementations). Total cell number and DNA frag- mentation in blastocysts derived from the vitri- fied morulae were assessed through TUNEL assay. The rate (%) of cleavage, blastocyst and expanded/hatched blastocyst did not differ among the culture medium supplementations within the follicle size of 3 - 10 mm (range 65.1 ± 4.3 - 75.4 ± 3.9;22.4 ± 3.9 - 36.4 ± 3.6;and 11.2 ± 2.9 - 23.3 ± 3.2, respectively) or ctively). Nevertheless, significantly lower (P cleavage and blastocyst rates with FBS and lower blastocyst rate with ScF supplementations were observed for the oocytes derived from compared to 3 - 10 mm follicles. The expression patterns of BcL-2, BAX, HSP1A1, GJA1 and BIRc5 tran- scripts varied significantly (P cases, except for BIRc5 in the blastocysts derived from 3 - 10 mm follicles. Following thaw and culture, the development (%) of vitrified morulae into expanded/hatched blastocysts was lower (P supplementation of

关键词： ivF Growth Factors Embryo Development Gene Expression cryotolerance Bovine

The Adverse Event Profile in Patients Treated with Transferon<sup>TM</sup>(Dialyzable Leukocyte Extracts): A Preliminary Report

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Pharmacology & Pharmacy 2015年第2期6卷 65-74页

作者： Toni Homberg Violeta Sáenz Jorge Galicia-carreón iván Lara Edgar cervantes-Trujano Maria c. Andaluz Erika Vera Oscar Pineda Julio Ayala-Balboa Alejandro Estrada-García Sergio Estrada-Parra Mayra Pérez-Tapia Maria c. Jiménez-Martínez clinical Trials Branch and clinical Immunology Service Unit of External Services and Clinical Research (USEIC) National School of Biological Sciences National Polytechnic Institute Mexico City Mexico Unit of Pharmacovigilance Unit of External Services and Clinical Research (USEIC) National School of Biological Sciences National Polytechnic Institute Mexico City Mexico Department of Immunology National School of Biological Sciences National Polytechnic Institute Mexico City Mexico Unit of R&D in Bioprocesses (UDIBI) National School of Biological Sciences National Poly-technic Institute Mexico City Mexico Department of Biochemistry Faculty of Medicine National Autonomous University of Mexico Mexico City Mexico

Background: Dialyzable leukocyte extracts (DLE) are heterogeneous mixtures of peptides less than 10 kDa in size that are used as immunomodulatory adjuvants in immune-mediated diseases. TransferonTM is DLE manufactured by National Polytechnic Institute (IPN), and is registered by Mexican health-regulatory authorities as an immunomodulatory drug and commercialized nationally. The proposed mechanism of action of TransferonTM is induction of a Th1 immunoregulatory response. Despite that it is widely used, to date there are no reports of adverse events related to the clinical safety of human DLE or TransferonTM. Objective: To assess the safety of TransferonTM in a large group of patients exposed to DLE as adjuvant treatment. Methods: We included in this study 3844 patients from our clinical Immunology Service at the Unit of External Services and clinical Research (USEIc), IPN. Analysis was performed from January 2014 to November 2014, searching for clinical adverse events in patients with immune-mediated diseases and treated with TransferonTM as an adjuvant. Results: In this work we observed clinical nonserious adverse events (AE) in 1.9% of patients treated with TransferonTM (MD 1.9, IQR 1.7 - 2.0). AE were 2.8 times more frequently observed in female than in male patients. The most common AE were headache in 15.7%, followed by rash in 11.4%, increased disease-related symptomatology in 10%, rhinorrhea in 7.1%, cough in 5.7%, and fatigue in 5.7% of patients with AE. 63% of adverse event presentation occurred from day 1 to day 4 of treatment with TransferonTM, and mean time resolution of adverse events was 14 days. In 23 cases, the therapy was stopped because of adverse events and no serious adverse events were observed in this study. conclusion: TransferonTM induced low frequency of nonserious adverse events during adjuvant treatment. Further monitoring is advisable for different age and disease groups of patients.

关键词： Dialyzable Leukocyte Extracts Adverse Events Monitoring Drug Safety Adjuvant Therapy Immunoregulation Guidelines Transfer Factor Pharmacovigilance

clinical and cost impact of intravenous proton pump inhibitor use in non-IcU patients

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World Journal of Gastroenterology 2010年第8期16卷 982-986页

作者： Soumana c Nasser Jeanette G Nassif Hani I Dimassi Department of Pharmacy Practice School of PharmacyLebanese American University

AIM:To assess the appropriateness of the indication and route of administration of proton-pump-inhibitors (PPIs) and their associated cost impact. METHODS:Data collection was performed prospec-tively during a 6-mo period on 340 patients who re-ceived omeprazole intravenously during their hospital stay in non-intensive care floors. Updated guidelines were used to assess the appropriateness of the indication and route of administration. RESULTS:complete data collection was available for 286 patients which were used to assess intravenous (iv) PPIs utilization. Around 88% of patients were receiving PPIs for claimed stress ulcer prophylaxis (sup) indication; of which,only 17% met the guideline criteria for sup indication,14% met the criteria for non-steroidal-anti-inflammatory drugs-induced ulcer prophylaxis,while the remaining 69% were identifi ed as having an unjustified indication for PPI use. Theinitiation of iv PPIs was appropriate in 55% of pa-tients. Half of these patients were candidates for switching to the oral dosage form during their hos-pitalization,while only 36.7% of these patients were actually switched. The inappropriate initiation of PPIs via the iv route was more likely to take place on the medical floor than the surgical floor (53% vs 36%,P = 0.003). The cost analysis associated with the appro-priateness of the indication for PPI use as well as the route of administration of PPI revealed a possible saving of up to $17 732.5 and $14 571,respectively. cONcLUSION:This study highlights the over-utili-zation of iv PPIs in non-intensive care unit patients. Restriction of iv PPI use for justified indications and route of administration is recommended.

关键词： cost saving Lebanon Non-intensive care unit patients Omeprazole Over-utilization Proton-pump-inhibitors Stress ulcer prophylaxis

Electronic structure analysis of c-H bond oxidation by high-valent iron complexes

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Electronic structure analysis of C-H bond oxidation by high-...

Soil properties, grassland management, and landscape diversity drive the assembly of earthworm communities in temperate grasslands

中国化学会第十二届全国量子化学会议

作者： Shengfa Ye cai-Yun Geng Bhaskar Mondal frank Neese Max-Planck Institute for chemical Energy conversion

High-valent iron-oxo species are implicated as key intermediates to selectively functionalize target c-H bonds in the catalytic cycles of a range of O2-activating iron *** reactions are typically performed under ambient conditions with high efficiency and ***,elucidation of the enzymatic reaction mechanism at the atomic level should aid in designing of novel bio-inspired catalysts that are able to oxidize unactivated c-H bond under mild chemical ***,we carried out systematic studies of hydroxylation of alkane c-H bond by high-valent iron-oxo and–nitrido complexes.1 We first evaluated all feasible reaction channels for alkane hydroxylation by iron（iv）oxo complexes.2 Analysis of the electronic structure changes along the key reaction coordinates reveals that the intrinsic oxidant is an iron（Ⅲ）oxyl species,which is generated by lengthening of the Fe-oxo bond.3,4 Then we extend our analysis to rationalize different reactivity of iron（iv/V/VI）-oxo and–nitrido complexes toward c-H bond oxidation5 and diiron systems.6

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Pedosphere 2021年第3期31卷 375-383页

作者： Kevin HOEFFNER Mathieu SANTONJA cécileMONARD Lou BARBE Mathilde LEMOING Daniel cLUZEAU University of Rennes CNRSECOBIO UMR 6553Rennes F-35000France INRAE AGROCAMPUS OUEST UMR SASRennes F-35000France Aix Marseille Université Avignon UniversitéCNRSIRDIMBEMarseille F-13397France

Earthworms are widespread soil organisms that contribute to a wide range of ecosystem *** such,it is important to improve our knowledge,still scanty,of the factors that drive the assembly of earthworm *** aim of the present study was to conjointly evaluate the effects on the assembly of earthworm communities of i)soil properties(texture,organic matter content,and pH),ii)grassland management(grassland age,livestock unit,and type of fertilization),iii)landscape diversity(richness,diversity of surrounding habitats,and grassland plant diversity),and iv)presence of *** study was conducted in temperate grasslands of Brittany,*** were sampled in 24 grasslands and,in three of these grasslands,they were sampled near a hedgerow or near a ditch(control without a hedgerow).Soil properties explained the larger portion of the variation in the earthworm community parameters compared to grassland management or landscape *** increase in soil organic matter content and pH were the most favorable factors for earthworm abundance and biomass,in particular for endogeic *** grassland management,the increase in the livestock unit was the most damaging factor for earthworm communities,in particular for the anecic earthworm biomass and endogeic species ***,landscape diversity negatively affected the total earthworm abundance and epigeic earthworm biomass,but it was related to an increase in the epi-anecic *** a finer scale,we also demonstrated that the presence of hedgerows surrounding grasslands enhanced earthworm species richness,especially within the epigeic and anecic ecological *** study highlights that the earthworm ecological categories respond specifically to environmental filters;further studies need to be conducted to elucidate the factors that drive the assembly of earthworm communities at this ecological category *** recommend that policymakers should act on landscape man

关键词： ecological categoryfield marginhedgerowlivestock unitsoil organic mattersoil PHtrampling

EcONOMIc-LOGIc, cONcEPTS AND METHODS: ANALYTIcAL AIDS IN SEDIMENT MANAGEMENT

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International Journal of Sediment Research 1989年 41-56页

作者： frank H. Bolhan ( consultant (Natural Resources Economies). c/o Agriculture Industries, Incorporated, 3002 Beacon Blvd., P. 0. Box 1076, West Sacramento, california 95691, U. S. A.)

In the introduction, the usefulness of economic analysis in the valuation of sediment management options is demonstrated for five different stages of the planning process: (i) policy formulation, (ii) the initial search for valid options, (iii) the predesign stage, (iv) determining the scope of the appraisal, and (v) monitoring the performance of completed projects. In the second section of the paper a scheme for classifying the economic and social effects of sediment-related effects on-site and off-site is designed and used to show how the social worth of a sediment management option can be estimated. The treatment of irreversibility, flexibility, externality and uncertainty in benefit-cost estimation is discussed in the third section of the paper, which concludes with a summary of the major points developed.

关键词： Economic analysis Sediment management Planning Environmental effects Social effects Diseconomy