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effects of Salt Pond Restoration on Benthic Flux: Sediment as a Source of Nutrients to the Water Column

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Journal of environmental Protection 2016年第7期7卷 1064-1071页

作者： brent R. Topping James S. Kuwabara James L. Carter Krista K. Garrett eric Mruz Sarah Piotter John Y. Takekawa U.S. Geological Survey Menlo Park CA USA U.S. Fish and Wildlife Service Fremont CA USA U.S. Geological Survey Vallejo CA USA

Understanding nutrient flux between the benthos and the overlying water (benthic flux) is critical to restoration of water quality and biological resources because it can represent a major source of nutrients to the water column. extensive water management commenced in the San Francisco Bay, Beginning around 1850, San Francisco Bay wetlands were converted to salt ponds and mined extensively for more than a century. Long-term (decadal) salt pond restoration efforts began in 2003. A patented device for sampling porewater at varying depths, to calculate the gradient, was employed between 2010 and 2012. Within the former ponds, the benthic flux of soluble reactive phosphorus and that of dissolved ammonia were consistently positive (i.e., moving out of the sediment into the water column). The lack of measurable nitrate or nitrite concentration gradients across the sediment-water interface suggested negligible fluxes for dissolved nitrate and nitrite. The dominance of ammonia in the porewater indicated anoxic sediment conditions, even at only 1 cm depth, which is consistent with the observed, elevated sediment oxygen demand. Nearby open-estuary sediments showed much lower benthic flux values for nutrients than the salt ponds under resortation. Allochthonous solute transport provides a nutrient advective flux for comparison to benthic flux. For ammonia, averaged for all sites and dates, benthic flux was about 80,000 kg/year, well above the advective flux range of -50 to 1500 kg/year, with much of the variability depending on the tidal cycle. By contrast, the average benthic flux of soluble reactive phosphorus was about 12,000 kg/year, of significant magnitude, but less than the advective flux range of 21,500 to 30,000 kg/year. These benthic flux estimates, based on solute diffusion across the sediment-water interface, reveal a significant nutrient source to the water column of the pond which stimulates algal blooms (often autotrophic). This benthic source may be augmented

关键词： Benthic Flux Nutrients Algal Blooms Restoration

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美国航海院校海事类数字文献资源调研

航海教育研究 2010年第3期27卷 97-99页

作者：那春光张世平 brent Hall Rebecca Whitney Carl Phillips 董颖大连海事大学图书馆辽宁大连116026 Maine Mariti me Academy Library castineme04420 California University Mariti me Academy 大连外国语学院图书馆辽宁大连116044

对美国7家航海学院图书馆的数字文献资源进行调研,归纳其图书馆主页上列出的海事类数字文献资源情况,对其中的核心资源进行简要的分析,并对有关海事类数字文献资源建设与服务提出建议。

关键词：美国航海院校数字文献资源核心资源

Synthesis of Solid Acid Catalysts Based on TiO2- SO42-and Pt/TiO2- SO42-Applied in n-Hexane Isomerization

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Open Journal of Metal 2013年第3期3卷 34-44页

作者： Juan Manuel Hernández enríquez Luz Aracely Cortez Lajas Ricardo García Alamilla estefanía ángeles San Martín Pedro García Alamilla edward brent Handy Guadalupe Cárdenas Galindo Luz Arcelia García Serrano CIeP Facultad de Ciencias Químicas Universidad Autónoma de San Luis Potosí Av. Dr. Manuel Nava #6 Zona Universitaria 78210 San Luis Potosí San Luis Potosí México Instituto Politécnico Nacional Centro Interdisciplinario de Investigaciones y Estudios sobre Medio Ambiente y Desarrollo 30 de Junio #1520 Barrio La Laguna Ticomán 07340 México D.F. México Instituto Tecnológico de Cd. Madero División de Estudios de Posgrado e Investigación Juventino Rosas y Jesús Urueta S/N Col. Los Mangos 89440 Cd. Madero Tamaulipas México Universidad Juárez Autónoma de Tabasco División Académica de Ciencias Agropecuarias Avenida Universidad S/N Zona Cultura Colonia Magisterial 86040 Villahermosa Tabasco México

The physicochemical properties and catalytic activity of pure and sulfated titanium oxide (TiO2 and ) is described in this work. Titanium hydroxide synthesized by the sol-gel method was impregnated with a 1 N H2SO4 solution, varying amount of sulfate ions () in the range from 10 to 20 wt%. Pure and modified hydroxides were calcined at 500°C for 3 h and then characterized by TGA-DTG, XRD, BeT, FT-IR, potentiometric titration with n-butylamine and 2-propanol dehydration. Catalytic activity of materials was tested in the n-hexane isomerization at 350°C. The results showed that TiO2 and mainly developed anatase phase. All have acceptable specific surface area (95-105 m2/g). Potentiometric titration with n-butylamine revealed that showed higher acidity (430-530 mV) than compared to pure TiO2 (﹣15 mV), indicating that this oxide only has weak acidity. The results showed good relationship between acidity determined by potentiometric titration with n-butylamine and the catalytic activity evaluated by 2-propanol dehydration and n-hexane isomerization. Titanium oxide with 20 wt% ofions was the material that demonstrated the highest catalytic activity for both reactions.

关键词： Acid Catalysts Sulfated Titanium Oxide Physico-Chemical Properties n-Hexane Isomerization

贯序和并行求解线性与非线性方程组的一类算法

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数学进展 1989年第1期18卷 55-61页

作者： e.Spedicato 邓乃扬意大利Bergamo大学北京工业大学应用数学系

1.引论 Abaffy,Broyden和spedicato在最近的论文中,提出了一类求解线性和非线性方程组的算法(有可能推广于求解其它问题,例如最优化问题).我们首先给出这类算法求解线性方程组时的基本形式.设线性方程组为或把它写成矩阵形式其中A=(a... 详细信息

1.引论 Abaffy,Broyden和spedicato在最近的论文中,提出了一类求解线性和非线性方程组的算法(有可能推广于求解其它问题,例如最优化问题).我们首先给出这类算法求解线性方程组时的基本形式.设线性方程组为或把它写成矩阵形式其中A=(a_1,…,a_m)是n×m阶矩阵,共秩q可以小于m.算法具有拟Newton型结构,其计算步骤如下:

关键词：线性方程组非线性方程数值解

Cryo-eM structure of the plant 26S proteasome

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Plant Communications 2022年第3期3卷 116-126页

作者： Susanne Kandolf Irina Grishkovskaya Katarina Belacic Derek L.Bolhuis Sascha Amann brent Foster Richard Imre Karl Mechtler Alexander Schleiffer Hemant D.Tagare ellen D.Zhong Anton Meinhart Nicholas G.Brown David Haselbach Research Institute of Molecular Pathology(IMP) Vienna BioCenter(VBC)Campus-Vienna-BioCenter 11030 ViennaAustria Department of Radiology and Biomedical Imaging Yale UniversityNew HavenCT 06510USA Department of Pharmacology and Lineberger Comprehensive Cancer Center University of North Carolina School of MedicineChapel HillNC 27599USA Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of TechnologyCambridgeMA 02139USA Vienna BioCenter PhD Program Doctoral School of the University at Vienna and Medical University of ViennaVienna BioCenter(VBC)ViennaAustria Institute of Physical Chemistry University of FreiburgAlbertstraße 21Freiburg 79104Germany CIBSS Centre for Integrative Biological Signalling Studies University of FreiburgFreiburgGermany

Targeted proteolysis is a hallmark of *** is especially important in long-lived cells that can be found in higher eukaryotes,like *** task is mainly fulfilled by the ubiquitin–proteasome ***,proteolysis by the 26S proteasome is vital to development,immunity,and cell *** the yeast and animal proteasomes are well characterized,there is only limited information on the plant *** determined the first plant 26S proteasome structure from Spinacia oleracea by single-particle electron cryogenic microscopy at an overall resolution of 3.3 A°.We found an almost identical overall architecture of the spinach proteasome compared with the known structures from mammals and ***,we noticed a structural difference in the proteolytic active b1 ***,we uncovered an unseen compression state by characterizing the proteasome’s conformational *** suspect that this new conformation of the 20S core protease,in correlation with a partial opening of the unoccupied gate,may contribute to peptide release after *** data provide a structural basis for the plant proteasome,which is crucial for further studies.

关键词： 26S proteasome spinach UPS cryo-eM conformational landscape

Physico-Chemical Features and Catalytic Activity of ZrO2-MoO3

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材料科学与工程（中英文版） 2010年第9期4卷 1-9页

作者： Hernandez Juan Garcia Luz Cortez Luz Garcia Ricardo Handy brent Cairdenas Maria Cueto Arturo Instituto Politecnico Nacional Escuela Superior de Ingenieria Textil Av. lnstituto Politecnico Nacional S/N Edificio # 8 Col. Linda Vista Mexico D.F. 07738. Mexico Instituto Tecnologico de Cd. Madero Division de Estudios de Posgrado e Investigacion Cd. Madero Tam. 89440 Mexico CIeP Facultad de Ciencias Qulmicas Universidad Aut6noma de San Luis Potosi San Luis Potosl 78210 Mdxico Universidad Autonoma Metropolitana-Azcapotzalco Av. San Pablo #180 Col. Reynosa Tamaulipas Delegacin Azcapotzalco Mexico D.F. 02200 oMexico

Zirconium hydroxide synthesized by sol-gel was impregnated with an aqueous solution of ammonium heptamolybdate in order to obtain 15 wt% of MoO3 on ZrO2. Pure and modified hydroxides were calcined at 400, 500, and 600 oC. In order to evaluate the catalytic activity for n-hexane isomerization, the materials were impregnated with 0.5 wt% of platinum and treated at 400 oC. For pure ZrO2 it was observed that the surface area decreases from 144 to 18 m2/g when the calcination temperature increases from 400 to 600 oC. The addition of Mo to zirconia increases the specific surface area (238-130 m2/g) in samples treated at the same temperatures. Pure zirconia transformed from tetragonal to monoclinic phase when calcined between 400 and 600 °C. However, this transformation did not occur in the ZrO2-MoO3 supports. The n-butylamine results showed that all the ZrO2-MoO3 supports presented a higher acidity (> 255 mV) than that corresponding to pure ZrO2 (- 48 mV), which presented only weakly acidic sites. Pt/ZrO2-MoO3 calcined at 600 oC proved to be the best catalyst for n-hexane isomerization, presenting a high selectivity to isomerization products (82%) at high conversion (72%).

关键词： MoO3 ZrO2 催化活性物理化学特征氢氧化锆焙烧温度比表面积浸渍材料

Manual aspiration thrombectomy in acute ST elevation myocardial infarction:New gold standard?

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World Journal of Cardiology 2011年第2期3卷 43-47页

作者： brent Rochon Youssef Chami Rajesh Sachdeva Joe K Bissett Nick Willis Barry F Uretsky Department of Medicine Central Arkansas Veterans Health SystemUniversity of Arkansas for Medical SciencesLittle RockAR 72205United States

Percutaneous coronary intervention(PCI) is the preferred method to treat ST segment myocardial infarction(STeMI).The use of thrombus aspiration(TA) may be particularly helpful as part of the PCI process,insofar as the presence of thrombus is essentially a universal component of the STeMI *** article reviews evidence favoring the routine use of TA,and the limitations of these *** on current evidence,we consider TA to be an important maneuver during STeMI PCI,even in the absence of visible angiographic thrombus,and recommend it whenever the presence of thrombus is likely.

关键词： Aspiration thrombectomy Myocardial infarction Guidelines Thrombus

Ten questions concerning future buildings beyond zero energy and carbon neutrality

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建筑节能 2017年第7期45卷 27-27页

作者： Na Wang Patrick e. Phelan Jorge G onzalez Chioke Harris G regor P. Henze Robert Hutchinson Jared Langevin Mary Ann Lazarus brent Nelson Chris Pyke Kurt Roth David Rouse Karma Sawyer Stephen Selkowitz 侯恩哲 <建筑节能>杂志社

Architects and planners have been at the forefront of envisioning a future built environment for millennia. How ever,fragmental view s that emphasize one facet of the built environment,such as energy,environment,or groundbreaking technologies,often do not achieve expected outcomes. Buildings are responsible for approximately one-third of w orldw ide carbon emissions and account for about 40% of primary energy consumption in the U. S. In addition to achieving the very ambitious goal of reducing building-associated greenhouse gas emissions by75% by 2050,buildings must improve their functionality and performance to meet current and future human,societal,and environmental needs in a changing w orld. In this article,w e introduce a new framew ork to guide potential evolution of the building stock in the next century,based on greenhouse gas emissions as the common thread to investigate the potential implications of new design paradigms,innovative operational strategies,and disruptive technologies. This framew ork emphasizes integration of multidisciplinary know ledge,scalability for mainstream buildings,and proactive approaches considering constraints and unknow *** framew ork integrates the interrelated aspects of the built environment through a series of quantitative metrics that aim to improve environmental outcomes w hile optimizing building performance to achieve healthy,adaptive,and productive buildings.

关键词：建筑节能建筑设计建筑风格建筑材料

Training stem cells for treatment of malignant brain tumors

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World Journal of Stem Cells 2014年第4期6卷 432-440页

作者： Shengwen Calvin Li Mustafa H Kabeer Long T Vu Vic Keschrumrus Hong Zhen Yin brent A Dethlefs Jiang F Zhong John H Weiss William G Loudon Neuro-On-cology and Stem Cell Research Laboratory Center for Neurosci-ence ResearchChildren’s Hospital of Orange CountyUniversity of California-IrvineOrangeCA 92868United States Department of Neurology University of California IrvineOrangeCA 92862United States Department of Pathology University of Southern CaliforniaLos AngelesCA 90033United States

The treatment of malignant brain tumors remains a challenge. Stem cell technology has been applied in the treatment of brain tumors largely because of the ability of some stem cells to infiltrate into regions within the brain where tumor cells migrate as shown in preclinical studies. However, not all of these efforts can translate in the effective treatment that improves the quality of life for pa-tients. Here, we perform a literature review to identify the problems in the field. Given the lack of efficacy of most stem cell-based agents used in the treatment of malignant brain tumors, we found that stem cell distribution(i.e., only a fraction of stem cells applied capable of targeting tumors) are among the limiting factors. We provide guidelines for potential improvements in stem cell distribution. Specifically, we use an engineered tissue graft platform that replicates the in vivo microenvironment, and provide our data to validate that this culture platform is viable for producing stem cells that have better stem cell distribution than with the Petri dish culture system.

关键词： Stem cells Malignant brain tumors engineered tissue graft Organotypic slice model