In addition to emission level reduction, combustion process optimization by modifications of pyrolysis boilers is aimed at fuel cost decrease. Knowledge of fuel composition and fuel combustion properties is important to the optimum and economical combustion process. The levels of emissions caused by the process can be reduced by several designs and operational modifications. This paper deals with modifications of combustion equipment in order to reduce harmful flue gas emissions in a boiler MA 23. The hot water boiler MA 23 belongs to gasification boilers for dry lump wood combustion; it is intended primarily for the heating of family houses, cottages, small office buildings and other small buildings and has the maximum required heat output of 23 kW. The boiler was tested in several modes, based on the requirements of the standard EN 303-5 dealing with emission limits. A basic requirement was the implementation of technical measures described in the paper and a proposal of method of regulation of flue gas volumetric flow rate and of installation in order to keep emission levels below the required limit.

关键词：排放水平；生物量；气体排放；生物质能

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NIH reimburses universities for both the direct and indirect costs of conducting research. Indirect costs cover general facility and administrative expenses, and are paid as a percentage, or rate, of certain direct costs of awarded grants. GAO was asked to look at the indirect costs of NIH-funded research. This report (1) identifies changes in reimbursements by NIH to universities for indirect costs of NIH-funded research; and (2) examines key factors affecting NIH reimbursement to universities for indirect costs and what assessment NIH has done to address any impact of these costs on NIH's research mission. GAO analyzed NIH data and interviewed officials at NIH, six universities, and other stakeholders. Universities were selected based on the number of grants and amount of funding received from NIH and their negotiated indirect cost rates.

关键词：医学研究；美国国立卫生研究院；生物医学；间接成本

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The welding process results in the formation of high concentrations of nano-sized particles loaded with toxic metals such as hexavalent chromium (Cr6+), nickel (Ni), and manganese (Mn). Welding fumes pose serious health risks to welders because fumes can cause respiratory and neurological ailments as well as cancer. Tightened occupational standards require an exposure reduction of at least 90that is not satisfied by current control technologies. There is also potential public concern about the environmental risks associated with the release of welding fumes into ambient air. The overall objective of this demonstration was to develop an innovative silica precursor technology that can limit the oxidation of chromium by quenching oxygen species and coating metal particles in welding fumes with a thin, amorphous silica layer. An additional objective was to assess the benefit of increased particle size distribution. The demonstration verified the feasibility and practicality of implementing silica precursor technology into DOD welding operations. Silica precursor technology was demonstrated to be an effective means of controlling metal emissions in welding fumes. The two-fold approach of limiting oxidation potential and coating metal particles with an amorphous silica layer goes beyond previous control technologies by addressing all the toxic metals, regardless of their oxidation state. This project demonstrated, through both a laboratory study and field tests, the benefits of adding silica precursor during the welding process.

关键词：空气污染；硅添加剂；有害空气污染物；排放量；焊接技术

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Neuroanatomy is one of the most challenging sections of anatomy to learn, partially related to the intricate relation of multiple 3D structures. As part of the medical student curriculum, it is usually taught in 2D using illustrations and plastinated brain section, since the number of hours devoted to anatomy have dropped in the curriculum, making the dissection of brain too time-consuming to be done. In this study we are analyzing the role of innate spatial ability of novices in learning some basic structures and placing them back in a 3D volumetric brain. Two tasks are performed after a short training session: the first one is to localize the ventricular tip as would be required during a temporal lobectomy, and the second task requires that the subject 'reconstruct' 3D anatomical structures within the context of our 3D brain model. We report our findings on the performance scores obtained from a population of subjects of differing backgrounds and spatial abilities.

关键词：神经解剖学；生物医学；三维可视化；虚拟现实

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Proliferation of invasive cattails (for example, Typha x glauca, T. angustifolia) is a concern of wetland managers across the country, and numerous methods have been used to control the spatial extent and density of the plant. To date, however, no single method has proven widely or consistently effective at reducing the long-term growth and spread of these species. We performed a multi-refuge study to evaluate the relative effects of growing-season and dormant-season prescribed burns on cattail production and to gain insight on variables such as soil moisture, groundwater, and biomass that affect the efficacy of burning as a control method. Results indicate total cattail cover recovers to pre-burn levels within 1 year regardless of whether the controlled burn was implemented during the growing season or dormant season. Growing-season burns, however, did result in lower aboveground and belowground cattail biomass 1-year post-burn, whereas no significant change in biomass was detected for dormant-season burns. Study results support the premise that burns implemented during the growing season should have a greater effect on nutrient reserves and cattail re-growth.

关键词：香蒲；植物生长;湿地;生物质能;作物;烧伤;地下水

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关键词：林野火灾;燃料;特征;生物质能;景观生态学

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Objective:p53,a tumor suppressor gene,is one of the hotspots in the world of the biomedical field.Mutation of p53 gene,which is found in approximately 50％ of human cancers,is a key event in carcinogenesis.This project aims to investigate the new characteristics of two p53 mutants,p53-W248 and p53-H175,in MCF-7 cells,so as to provide the experimental basis for understanding the functional alternations of mutant p53.Methods:In this study,MCF-7 cells transfected with p53-H175 or p53-W248 plasmids were used as experimental group and the MCF-7 cells transfected wild type p53 plasmid were used as control group.Then the biological effects at the cellular level were investigated using 3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay,flow cytometry analysis and cell scratch test.Results:MTT assay showed that p53-W248 might promote cell proliferation in MCF-7 cells.The results of flow cytometry indicated that no significant effect on cell cycle progression and cell apoptosis by p53-H175 or p53-W248 in cells.The cell scratch test showed that p53-H175 could increase the ability of cell migration.Conclusion:p53-H175 could lead to the promotion of tumor cell migration,while p53-W248 may promote tumor cell proliferation,p53-H175 and p53-W248 might have acquired some new characteristics of oncogenes.

关键词：细胞增殖；细胞周期；细胞迁移；生物医药

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Photovoltaics is the most popular technology choice for off-grid rural electrification. In the Philippines, some major socio-economic programs of the government utilize photovoltaics to bring electric power and economic development in remote rural areas. The main advantage of PV over other renewable energy technologies is its virtually inexhaustible source of power, i.e., the sun. PV converts solar radiation directly into electricity. The geographical location of the Philippines enables it to harness solar energy because of high daily insolation, ranging from 3.5 to 5.2 kWh per square meter, and the low seasonal variation of solar radiation. The solar potential is greatest during the summer months of May to July when the sun is positioned over the Northern Hemisphere. Conversely, the months with the weakest sunlight are November to January.

关键词：农村，太阳能；电力；光伏电站；可再生能源；太阳辐射

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America's Children and the Environment (ACE) is EPAs report presenting data on children's environmental health. ACE brings together information from a variety of sources to provide national indicators in the following areas: Environments and Contaminants, Biomonitoring, and Health. Environments and Contaminants indicators describe conditions in the environment, such as levels of air pollution. Biomonitoring indicators include contaminants measured in the bodies of children and women of child-bearing age, such as children's blood lead levels. Health indicators report the rates at which selected health outcomes occur among U.S. children, such as the annual percentage of children who currently have asthma. Accompanying each indicator is text discussing the relevance of the issue to children's environmental health and describing the data used in preparing the indicator. Wherever possible, the indicators are based on data sources that are updated in a consistent manner, so that indicator values may be compared over time. This report is the third edition of ACE (referred to as ACE3); previous editions of ACE were published in 2000 and 2003.

关键词：健康环保；环境监测；污染物；空气污染

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A goal throughout much of the developed world is to replace a considerable portion of petroleum fuel with biofuels, including those from cellulosic biomass sources (U.S. Department of Energy, 2006). Plant species that are more water-use efficient are preferred, and biofuel crops will be needed for each specific environment. Cellulosic biomass crops have been identified for most agro-ecoregions as defined by temperature, rainfall, and soil types, but few have been identified for semiarid, subtropical regions, such as the Southern High Plains of the USA, which is dominated by short, mixed, and tallgrass prairie.

关键词：生物燃料；植物种类；纤维素生物燃料作物；作物

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