Previous work by us and others demonstrates induction of a systemic pro-inflammatory and pro-coagulant state in response to inhalation of environmental particulate matter. Our work demonstrated PM exposure activated platelets to a enhanced state of reactivity and suggested this could be a key factor in adverse cardiovascular events. This project evaluated pulmonary inflammation and systemic inflammatory and platelet responses to fine and ultrafine (PM2.5) ambient particulate matter collected from an urban (Sacramento) and rural (Davis) location. The objective of these experiments was to determine whether prior chelation of transition metals with deferoxamine mesylate (DFM) or binding of bacterial source endotoxin by polymyxin B reduced pulmonary and systemic responses to PM2.5. We hypothesized those inflammatory responses to a more transition metal rich urban source PM2.5 would be inhibited more by metal chelation while rural source PM2.5 would be more affected by endotoxin binding. Adult mice were given intratracheal instillations of collected PM2.5 and pulmonary pathology, systemic cytokine concentrations, and platelet activation were evaluated 24 hours later. To better assess contributions of aromatic hydrocarbons, oxidants or pro-inflammatory responses to biologically active material like endotoxin, we used laser capture microscopy to probe specific anatomic locations in lung for gene responses associated with each of these components.

关键词：大气；环境污染；健康

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This project centered on a close interaction between the TCON Division of Fire line, Inc. and various individuals affiliated with the College of Science, Technology, Engineering, and Mathematics (STEM) at Youngstown State University (YSU). Fireline, a local company within 10 minutes walking distance from the YSU campus core, has developed a unique process that utilizes displacement reactions to transform ceramic preforms into ceramic-metallic co-continuous interpenetrating phase composites with enhanced properties while retaining the original shape and dimensions of the preform. Through initial development efforts, it was discovered that TCON(TradeName) composite materials have extraordinary macro-, micro-, and nanoscale features that lead to their exceptional properties ideal for applications that require cost effective, lightweight materials. The unique properties of TCON composites in general are derived from the fine interlocking of ceramic and metallic phases throughout the composite microstructure. The ceramic phase provides high stiffness, low density and high strength to the composite, while the continuous network of reinforced metal gives high thermal & electrical conductivity, and high fracture toughness to the material. Such properties make these materials excellent candidates for replacing traditional materials in a number of applications, such as high wear/corrosion resistant refractory shapes for molten metal transport and/or containment in industrial processes (the major area in which Fireline currently commercializes some of its TCON products), or for new applications, including light weight, high strength components for vehicle braking systems.

关键词：大气；空气污染；新型复合

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According to the NRC and the USGCRP, changes in the earth's climate--including higher temperatures, changes in precipitation, rising sea levels, and increases in the severity and frequency of severe weather events--are under way and expected to grow more severe over time. These impacts present significant risks to the nation's energy infrastructure. Economic losses arising from weather-related events--including floods, droughts, and storms--have been large and are increasing, according to USGCRP. Adaptation--an adjustment to natural or human systems in response to actual or expected climate change--is a risk-management strategy to help protect vulnerable sectors and communities that might be affected by climate change. GAO was asked to examine the vulnerability of the nation's energy infrastructure to climate change impacts. This report examines: (1) what is known about potential impacts of climate change on U.S. energy infrastructure; (2) measures that can reduce climate-related risks and adapt energy infrastructure to climate change; and (3) the role of the federal government in adapting energy infrastructure and adaptation steps selected federal entities have taken. GAO reviewed climate change assessments; analyzed relevant studies and agency documents; and interviewed federal agency officials and industry stakeholders, including energy companies at four sites that have implemented adaptive measures.

关键词：大气；能源；气候变化

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This project was an initial effort to investigate the feasibility of an instrument combining real-time atmospheric particle composition measurements using an ATOFMS (Atmospheric Time-Of-Flight Mass Spectrometer) such as those performed by Prathers group at the University of California, San Diego (UCSD) with multi-wavelength scattering measurements of the type investigated by Sorensen et al., of Kansas State University (KSU). In this Phase I effort we proposed to investigate near-angle scattering and the possibility of integration of a multi-wavelength scattering instrument into the UCSD ATOFMS. After an initial optical design and calculations, we discovered issues with the theory of measurement and with mechanical integration. Evidence emerged that the method of multi-wavelength scattering is only efficacious for spherical particles, while most atmospheric particles are non-spherical fractal aggregates. We also determined that the integration of the detector into existing ATOFMS instruments would be severely limited by volume constraints, and additional volume would require prohibitive additional pumping compared with the existing ATOFMS systems. Based on this evidence, we decided not to pursue a Phase II effort.

关键词：大气；光子；气溶胶

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Carbon storage and flux estimates for the two national forests in Alaska are provided using inventory data from permanent plots established in 19952003 and remeasured in 20042010. Estimates of change are reported separately for growth, sapling recruitment, harvest, mortality, snag recruitment, salvage, snag falldown, and decay. Although overall aboveground carbon mass in live trees did not change in the Tongass National Forest, the Chugach National Forest showed a 4.5 percent increase. For the Tongass National Forest, results differed substantially for managed and unmanaged forest: managed lands had higher per-acre rates of sequestration through growth and recruitment, and carbon stores per acre that were higher for decomposing downed wood, and lower for live trees and snags. The species composition of carbon stores is changing on managed lands, with a carbon mass loss for yellow-cedar but increases for red alder and Sitka spruce. On unmanaged lands, the Chugach National forest had carbon mass increases in Sitka spruce and white spruce, and the Tongass National Forest had increases in western redcedar and red alder.

关键词：大气；碳通量；森林公园

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In this review, we summarize the literature from the warm deserts of North America and consider leaf (Anet), soil (Rs), and plant community (aboveground net primary productivity; ANPP) studies from the Mojave, Sonoran, and Chihuahuan Deserts to determine if common trends exist across measurement scales that can be utilized to effectively manage the warm deserts. Furthermore, we investigate the potential management strategies that may increase carbon sequestration or minimize carbon losses in this region. We begin by describing the warm deserts in the southwestern United States and consider climate change projections for this region. We then examine how climate change may affect NEE and carbon sequestration.

关键词：大气；碳存储；空气管理

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This report explores the volatility of primary organic aerosol (POA) emitted from light duty gasoline-powered vehicles at atmospherically relevant concentrations using state of the science instrumentation. Existing POA partitioning models were tested through analysis of emissions changes that result from perturbations to the dilution air used during vehicle sampling.

关键词：大气；有机气溶胶；sip分析

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Superparamagnetic iron oxide nanoparticle (SPION) has attracted a great deal of attention in the fields of medicine and biology due to its non-toxicity, large specific surface area, amenability to various surface fuctionalization, and unique magnetic properties. For biomedical applications, we synthesized two kinds of SPIONs by co-precipitation and polyol methods, designated as C- and P-SPIONs, respectively. To increase their solubility and stability in an aqueous solution, both of the SPIONs were functionalized with hyperbranched polyglycerol (PG) through ring-opening polymerization of glycidol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) measurements revealed that the P-SPION provided individual nanoparticles without aggregation after the PG fuctionalization. This P-SPION-PG was highly soluble not only in pure water (＞ 40 mg/mL), but also in a phosphate buffer solution (＞ 25 mg/mL). Such high solubility enabled separation of P-SPION-PG according to their size by size exclusion chromatography (SEC). The size-separated P-SPION-PG shows a gradual increase in transverse relaxivity (r_2) with increasing particle size. The hydroxyl group in PG also serves as a scaffold for further surface functionalization. For targeted cell labeling, we functionalized P-SPION-PG through multi-step organic transformations (-OH → -OTs (tosylate) → -N_3 → -RGD) including click chemistry as a key step to impart targeting specificity by immobilization of cyclic RGD peptide on the surface. The targeting effect was demonstrated by the cell experiments; P-SPION-PG-RGD was taken up by the cells overexpressing α_vP_3-integrin such as U87MG and A549. In addition, near-infrared (NIR) fluorescence dye (IRdye 800CW) was immobilized on the surface of P-SPION-PG through amide linkage. The resulting P-SPION-PG-IRdye showed good solubility in phosphate buffered saline (PBS) and strong fluorescence in NIR region, which may find application in optical/MR bimodal imaging.

关键词：氧化铁；纳米颗粒；聚甘油；功能化

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In contrast to composite long rods, composite post insulators are subjected mainly to loads which act perpendicular to the longitudinal axis of the insulator and thus produce bending stresses over the cross-section of the insulator. These bending stresses reach their maximum value at the point at which the FRP rod is fixed in the metal fitting (circled in red in Fig. 3.1), the latter being located where the insulator is attached to the support structure, whether this be the cross-arm of a steel lattice tower for an overhead transmission line, the coupling plate of a tubular steel or concrete pole, or the platform in a pole-mounted substation. Calculation of these bending stresses is discussed in detail in Sect. 3.9.

关键词：复合长棒；绝缘体；钢铁

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The ideal materials used for biomedical application are of high biocompatibility, acceptable strength, minimal tissue responses and low cytotoxicity. Polyhydroxyalkanoates (PHAs) represent a class of biopolymers composed of different types of hydroxyalkanoic acids monomers, which are produced by microorganisms under unbalanced growth conditions. With excellent biodegradability and biocompatibility, PHAs attract more and more attention of various areas especially medicine and health care, where they have already been used in lots of aspects, ranging from wound dressings, drug delivery applications, and surgical implants to other medical devices. However, it is a crucial issue should be taken into consideration that the potential cytotoxicity is caused by both the chemical compositions and the methods of processing and forming PHAs, such as the surface properties and the chemical purities of the materials. Therefore, systematic assessment of PHAs' cytotoxicity is very important for their biological and biomedical applications. In this chapter, we focus on the cytotoxicity caused by different types of PHAs and the mechanisms behind are also discussed.

关键词：聚羟基烷酸酯；细胞毒性；生物相容性；生物医学

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