Structure of soot-containing laminar jet diffusion flames

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76650/1/AIAA-1993-708-697.pd

Spatial distribution of polychlorinated biphenyls, organochlorine pesticides, and dechlorane plus in Northeast Asia

XAD-2 resin-based passive air samplers (PAS) were deployed for one year at eight cities in Mongolia, China, and South Korea to investigate the spatial distribution of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and dechlorane plus (DP). PCB levels were highly correlated with population size and density in China and South Korea. In Mongolia, PCB levels were relatively high considering the low population. In the cases of OCPs and DP, a country-specific distribution was observed. The highest levels of HCHs (hexachlorocyclohexane isomers) and DDTs (dichlorodiphenyl trichloroethane isomers) were detected at sites in China, whereas the highest endosulfan and DP levels were measured at South Korean sites. These results strongly reflected the patterns of use of these chemicals. Mirex, an insecticide never registered in Mongolia and South Korea, was detected at all sampling sites; this is likely to have resulted from long-range transport. Nevertheless, OCPs were generally low in Mongolia. This study confirms that PAS results reflect well the past and current usage of POPs in Northeast Asia. (C) 2012 Elsevier Ltd. All rights reserved.X112624sciescopu

The aadB Gene Cassette Is Associated with bla(SHV) Genes in Klebsiella Species Producing Extended-Spectrum β-Lactamases

Integrons were detected in 37 (72.5%) of 51 Klebsiella spp. producing extended-spectrum beta-lactamases by PCR with primers that targeted integrase genes and cassette regions. PCR and amplicon sequencing of the cassette regions revealed aadB and aadA2 gene cassettes that confer resistance to a range of aminoglycosides. aadB was associated with a class 1 integron on a 28-kb plasmid, pES1, that also contained bla(SHV-12) and IS26

The electrochemical behavior of poly 1-pyrenemethyl methacrylate binder and its effect on the interfacial chemistry of a silicon electrode

The physico-chemical properties of poly (1-pyrenemethyl methacrylate) (PPy) are presented with respect to its use as a binder in a Si composite anode for Li-ion batteries. PPy thin-films on Si(100) wafer and Cu model electrodes are shown to exhibit superior adhesion as compared to conventional polyvinylidene difluoride (PVdF) binder. Electrochemical testing of the model bi-layer PPy/Si(100) electrodes in a standard organic carbonate electrolyte reveal higher electrolyte reduction current and an overall irreversible cathodic charge consumption during initial cycling versus the uncoated Si electrode. The PPy thin-film is also shown to impede lithiation of the underlying Si. XAS, AFM, TGA and ATR-FTIR analysis indicated that PPy binder is both chemically and electrochemically stable in the cycling potential range however significant swelling is observed due to a selective uptake of diethyl carbonate (DEC) from the electrolyte. The increased concentration of DEC and depletion of ethylene carbonate (EC) at the Si/PPy interface leads to continuous decomposition of the electrolyte and results in non-passivating behavior of the Si(100)/PPy electrode as compared to pristine silicon. Consequently, PPy binder improves the mechanical integrity of composite Si anodes but it influences mass transport at the Si(100)/PPy interface and alters electrochemical response of silicon during cycling in an adverse manner

Norovirus Excretion in an Aged-Care Setting▿

Norovirus genogroup II excretion during an outbreak of gastroenteritis was investigated in an aged-care facility. Viral shedding peaked in the acute stage of illness and continued for an average of 28.7 days. The viral decay rate was 0.76 per day, which corresponds to a viral half-life of 2.5 days

Human macrophage cathepsin B-mediated C-terminal cleavage of apolipoprotein A-I at Ser²²⁸ severely impairs antiatherogenic capacity

Apolipoprotein A-I (apoA-I) is the major component of HDL and central to the ability of HDL to stimulate ATP-binding cassette transporter A1 (ABCA1)-dependent, antiatherogenic export of cholesterol from macrophage foam cells, a key player in the pathology of atherosclerosis. Cell-mediated modifications of apoA-I, such as chlorination, nitration, oxidation, and proteolysis, can impair its antiatherogenic function, although it is unknown whether macrophages themselves contribute to such modifications. To investigate this, human monocyte-derived macrophages (HMDMs) were incubated with human apoA-I under conditions used to induce cholesterol export. Two-dimensional gel electrophoresis and Western blot analysis identified that apoA-I is cleaved (∼20-80%) by HMDMs in a time-dependent manner, generating apoA-I of lower MW and isoelectric point. Mass spectrometry analysis identified a novel C-terminal cleavage site of apoA-I between Ser²²⁸-Phe²²⁹. Recombinant apoA-I truncated at Ser²²⁸ demonstrated profound loss of capacity to solubilize lipid and to promote ABCA1-dependent cholesterol efflux. Protease inhibitors, small interfering RNA knockdown in HMDMs, mass spectrometry analysis, and cathepsin B activity assays identified secreted cathepsin B as responsible for apoA-I cleavage at Ser²²⁸. Importantly, C-terminal cleavage of apoA-I was also detected in human carotid plaque. Cleavage at Ser²²⁸ is a novel, functionally important post-translational modification of apoA-Imediated byHMDMsthat limits the antiatherogenic properties of apoA-I.17 page(s