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Crop yields and soil organic carbon dynamics in a long-term fertilization experiment in an extremely arid region of northern Xinjiang, China

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Journal of Arid Land 2017年第3期9卷 345-354页

作者： LYU Jinling LIU Hua WANG Xihe rodrigo OLAVE TIAN Changyan LIU Xuejun State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Graduate University of Chinese Academy of Sciences Beijing 100049 China Institute of Plant Nutrition Resources and Environmental Sciences Henan Academy of Agricultural Sciences Zhengzhou 450000 China Institute of Soils and Fertilizers Xinjiang Academy of Agricultural Sciences Urumqi 830000 China Agri-Food and Biosciences Institute Hillsborough BT26 6DR United Kingdom College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China

A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control （CK） and six different combinations of phosphorus （P）, potassium （K）, nitrogen （N）, straw （S） and animal manure （M）. The balanced fertilization treatments had significantly （P〈0.05） higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate （NPK） and 1/3 N from farmyard manure （NPKM） had a higher average yield than the other treatments. The average yields （over the 23 years） in the treatments of NPK, and urea, calcium superphosphate （NP） did not differ significantly （P〉0.05） but were higher than that in the treatment with urea and potassium sulfate （NK; P〈0.05）. The results also show that the highest increases in SOC （P〈0.05） occurred in NPKM with a potential increase of 1.2 t C/（hm2.a）. The increase in SOC was only 0.31, 0.30 and 0.12 t C/（hm2.a） for NPKS （9/10 N from NPK and 1/10 N from straw）, NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration.

关键词： long-term fertilization experiment extremely arid conditions soil organic carbon organic C inputs Xinjiang

Trends of stellar entropy along stellar evolution

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Research in Astronomy and Astrophysics 2016年第2期16卷 1-12页

作者： Marcio Guilherme Bronzato de Avellar rodrigo Alvares de Souza Jorge Emesto Horvath Instituto de Astronomia Geofísica e Ciencias Atmosféricas-Universidade de Sao PauloRua do Matao1226

This paper is devoted to discussing the difference in the thermodynamic entropy budget per baryon in each type of stellar object found in the Universe. We track and discuss the actual decrease of the stored baryonic thermodynamic entropy from the most primitive molecular cloud up to the final fate of matter in black holes, passing through evolved states of matter as found in white dwarfs and neutron stars. We then discuss the case of actual stars with different masses throughout their evolution, clarifying the role of the virial equilibrium condition for the decrease in entropy and related issues. Finally, we discuss the role of gravity in driving the composition and the structural changes of stars with different Main Sequence masses during their evolution up to the final product. Particularly, we discuss the entropy of a black hole in this context arguing that the dramatic increase in its entropy, differently from the other cases, is due to the gravitational field itself.

关键词： stars formation -- stars neutron -- black holes

Structural Optimization of Metal and Polymer Ore Conveyor Belt Rollers

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Computer Modeling in Engineering & Sciences 2022年第12期133卷 601-618页

作者： Joao Pedro Ceniz rodrigo de Sá Martins Marco Antonio Luersen Tiago Cousseau Department of Mechanical Engineering Federal University of Technology-Parana(UTFPR)Curitiba81280-340Brazil

Ore conveyor belt rollers operate in harsh environments,making them prone to premature *** service lives are highly dependent on the stress field and bearing misalignment angle,for which limit values are defined in a *** this work,an optimization methodology using metamodels based on radial basis functions is implemented to reduce themass of twomodels of *** a structural point of view,one of the rollers ismade completely of metal,while the other also has some components made of polymeric *** objective of this study is to develop and apply a parametric structural optimization methodology to minimize the mass of the two models of *** represent the mechanical behavior of the rollers,simulations were performed using the finite element *** the numerical optimization process,the variable parameters were the dimensions of the shaft and external *** geometric configuration that corresponded at the same time to the lowest mass and acceptable ranges for the stress and bearingmisalignment angle was *** the proposed methodology,a 32.3% reduction in mass was obtained for a metal roller design and an 18.9% reduction for a polymer *** both cases,the constraints were not *** the all-metal roller,the safety factors for the maximum stress and bearingmisalignment angle were 1.44 and 1.75,respectively,while for the polymer roller the corresponding figures were 1.50 and *** work describes a low-computational-cost optimization methodology for roller designs that have been little studied in the ***,the methodology could be adapted for use with other types of rollers and rollers made of different materials.

关键词： Conveyor belt rollers structural optimization surrogate models radial basis functions

Comparative Analysis of Stability and Electromagnetic Transient Studies for HVDC Multi-infeed Systems

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CSEE Journal of Power and Energy Systems 2017年第3期3卷 253-259页

作者： Marcio Szechtman Maria Jose Ximenes Arnoldo rodrigo Saavedra Dual Consulting Rio de JaneiroBrazil ONS-National System Operator of Brazil Rio de JaneiroBrazil Electel Engineering Rio de JaneiroBrazil

In previous papers,the authors presented various electromagnetic transient(EMT)results for multi-infeed configurations focusing on possible effects from failures in one link being transferred to others in terms of induced commutation failures(CF),either during the fault events or after fault clearing in the recovery ***,the AC system networks in these cases were represented by simplified *** interesting conclusions arose from these publications without enabling a much-detailed analysis of overall system effects,which is only possible when the network is modeled in full *** paper aims at complementing and comparing simulation results on HVDC multi-infeed configurations using both dynamic stability and electromagnetic transient,while establishing some basic proposals for optimal use of both *** identifies the limitations from each type of study so that a comprehensive and useful analysis of HVDC multi-infeed systems can be obtained.

关键词： AC/DC interactions commutation failures HVDC multi-infeed configurations

The effects of plyometric jump training on lower-limb stiffness in healthy individuals:A meta-analytical comparison

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Journal of Sport and Health Science 2023年第2期12卷 236-245页

作者： Jason Moran Bernard Liew rodrigo Ramirez-Campillo Urs Granacher Yassine Negra Helmi Chaabene School of Sport Rehabilitation and Exercise SciencesUniversity of EssexColchesterEssex CO43SQUK Department of Physical Activity Sciences Universidad de Los LagosOsorno 5290000Chile Division of Training and Movement Science University of PotsdamPotsdam 14469Germany Higher Institute of Sport and Physical Education of Ksar Saı¨d University of Manouba Tunis 2037Tunisia High Institute of Sports and Physical Education of Kef University of JendoubaJendouba 8189Tunisia

Purpose:This study aimed to examine the effects of plyometric jump training(PJT)on lower-limb ***:Systematic searches were conducted in PubMed,Web of Science,and *** participants included healthy males and females who undertook a PJT programme isolated from any other training ***:There was a small effect size(ES)of PJT on lower-limb stiffness(ES=0.33,95%confidence interval(95%CI):0.07-0.60,z=2.47,p=0.01).Untrained individuals exhibited a larger ES(ES=0.46,95%CI:0.08-0.84,p=0.02)than trained individuals(ES=0.15,95%CI:-0.23 to 0.53,p=0.45).Interventions lasting a greater number of weeks(>7 weeks)had a larger ES(ES=0.47,95%CI:0.06-0.88,p=0.03)than those lasting fewer weeks(ES=0.22,95%CI:-0.12 to 0.55,p=0.20).Programmes with2 sessions per week(ES=0.20,95%CI:-0.10 to 0.50,p=0.18).Programmes with500 jumps per week had negative effects(ES=-0.22,95%CI:-1.10 to 0.67,p=0.63).Programmes with>7.5 jumps per set showed larger effect sizes(ES=0.55,95%CI:0.02-1.08,p=0.04)than those with7 weeks).

关键词： Jumps Stretch shortening cycle Tendon

Macrofaunal communities of threatened subtidal maёrl seabeds on Tenerife (Canary Islands, north-east Atlantic Ocean) in summer

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Acta Oceanologica Sinica 2012年第1期31卷 98-105页

作者： rodrigo Riera Juan Domingo Delgado Myriam Rodríguez Óscar Monterroso Eva Ramos Centro de Investigaciones Medioambientales del Atlántico(CIMA SL) C/Arzobispo Elías Yanes Área de Ecología Departamento de Sistemas FísicosQuímicos y Naturales.Facultad de Ciencias ExperimentalesUniversidad Pablo de Olavide

This study contributes with the first data on physical and taxonomical structure of macrofaunal assemblages of maerl beds from the Canary Islands. Maerl beds and Cymodocea nodosa meadows of the Canary Islands are considered biodiversity hot-spots in terms of taxonomic and functional biodiversity with a broad geographical and depth ranges. The authors have studied the structure of the macrofaunal assemblages on different habitat types （Cymodocea, Caulerpa, sabellid field, garden eel and maerl beds）. Samples were taken at a range of depths between 14 and 46 m. Correlations were performed among abiotic variables （granulometry, organic matter, nitrogen and phosphates） and the most abundant taxa. Similarity analysis was performed to explore the patchiness of seabeds at a local scale. Significant differences were found in macrofaunal assemblages among seabed types, with highest abundances and lowest biodiversity in sabellid fields, where the sabellid Bispira viola dominated. The polychaetes Aponuphis bilineata and Chone filicauda and the mollusc Turritella brochii were the most abundant taxa on maerl beds. The mosaic of granulometric conditions would explain the associated macroinfaunal community structure and contribute to the creation of diversity on these relatively well preserved seabeds at a local scale.

关键词： Macrofauna Polychaetes Amphipods Molluscs soft-bottoms subtidal Tenerife Canary Islands

The Discrete Orthogonal Polynomial Least Squares Method for Approximation and Solving Partial Differential Equations

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Communications in Computational Physics 2008年第3期3卷 734-758页

作者： Anne Gelb rodrigo B.Platte W.Steven Rosenthal Department of Mathematics and Statistics Arizona State UniversityTempeArizona 85287USA

We investigate numerical approximations based on polynomials that are orthogonal with respect to a weighted discrete inner product and develop an algorithm for solving time dependent differential *** focus on the family of super Gaussian weight functions and derive a criterion for the choice of parameters that provides good accuracy and stability for the time evolution of partial differential *** results show that this approach circumvents the problems related to the Runge phenomenon on equally spaced nodes and provides high accuracy in *** time stability,small corrections near the ends of the interval are computed using local polynomial *** numerical experiments illustrate the performance of the method.

关键词： Discrete least-squares orthogonal polynomials spectralmethods high order numerical methods uniform grid.

Neuroplastin in Ca^(2+)signal regulation and plasticity of glutamatergic synapses

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Neural Regeneration Research 2023年第8期18卷 1705-1706页

作者： Ayse Malci Xiao Lin Yun Stone Shi rodrigo Herrera-Molina Center for Neuroscience Research Children’s National Medical CenterWashingtonDCUSA Guangdong Institute of Intelligence Science and Technology ZhuhaiGuangdong ProvinceChina Combinatorial Combinatorial NeuroImaging Leibniz Institute for NeurobiologyMagdeburgGermany Centro Integrativo de Biología y Química Aplicada Universidad Bernardo O’HigginsSantiagoChile

The main function of neurons is information transmission in the form of action *** fulfill this duty,neurons are connected functionally with each other via synapses,the microscopic structures where specialized molecular machinery is strategically placed to release and receive neurotransmitters and to generate and extinguish calcium(Ca^(2+))*** synaptic molecular components are highly dynamic and they influence each other to confer structural and functional adaptability(plasticity)to neuronal communication(Biederer et al.,2017).

关键词： plasticity specialized structural

Different risk factors influence peptic ulcer disease development in a Brazilian population

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World Journal of Gastroenterology 2012年第38期18卷 5404-5411页

作者： rodrigo Buzinaro Suzuki rodrigo Faria Cola Larissa Tranquilino Bardela Cola Camila Garcia Ferrari Fred Ellinger Altino Luiz Therezo Luis Carlos da Silva André Eterovic Márcia Aparecida Sperana Department of Genotyping Hemocenter Marilia Medical School Marilia 17519-030 So Paulo Brazil Center for Natural and Human Sciences Universidade Federal do ABC Santo André 09210-170 So Paulo Brazil Department of Molecular Biology Marilia Medical School Marilia 17519-030 So Paulo Brazil Department of Pathology Marilia Medical School Marilia 17519-030 So Paulo Brazil

AIM: To investigate age, sex, histopathology and Helicobacter pylori (H. pylori) status, as risk factors for gastroduodenal disease outcome in Brazilian dyspeptic *** submitted to upper gastroscopy at Hospital das Clinicas of Marilia, antral biopsy specimens were obtained and subjected to histopathology and H. pylori diagnosis. All patients presenting chronic gastritis (CG) and peptic ulcer (PU) disease localized in the stomach, gastric ulcer (GU) and/or duodenal ulcer (DU) were included in the study. Gastric biopsies (n = 668) positive for H. pylori by rapid urease test were investigated for vacuolating cytotoxin A (vacA ) medium (m) region mosaicism by polymerase chain reaction. Logistic regression analysis was performed to verify the association of age, sex, histopathologic alterations, H. pylori diagnosis and vacA m region mosaicism with the incidence of DU, GU and CG in patients. RESULTS: Of 1466 patients submitted to endoscopy, 1060 (72.3%) presented CG [male/female = 506/554; mean age (year) ± SD = 51.2 ± 17.81], 88 (6.0%) presented DU [male/female = 54/34; mean age (year) ± SD = 51.4 ± 17.14], and 75 (5.1%) presented GU [male/female = 54/21; mean age (year) ± SD = 51.3 ± 17.12] and were included in the comparative analysis. Sex and age showed no detectable effect on CG incidence (overall c 2 = 2.1, P = 0.3423). Sex [Odds ratios (OR) = 1.8631, P = 0.0058] but not age (OR = 0.9929, P = 0.2699) was associated with DU and both parameters had a highly significant effect on GU (overall c 2 = 30.5, P < 0.0001). The histopathological results showed a significant contribution of ageing for both atrophy (OR = 1.0297, P < 0.0001) and intestinal metaplasia (OR = 1.0520, P < 0.0001). Presence of H. pylori was significantly associated with decreasing age (OR = 0.9827, P < 0.0001) and with the incidence of DU (OR = 3.6077, P < 0.0001). The prevalence of m1 in DU was statistically significant (OR = 2.3563, P = 0.0018) but not in CG (OR = 2.678, P = 0.0863) and G

关键词： Helicobacter pylori Gastric ulcer disease Duodenal ulcer disease Gastric atrophy Helicobacter pylori vacuolating cytotoxin A medium region mosaicism