Temperature-programmed reaction/desorption and reflection-absorption infrared spectroscopy have been employed to investigate the adsorption and decomposition of HOCH 2 CH 2 NH 2 on Cu(100). HOCH 2 CH 2 NH 2 molecules desorb from the multilayer and monolayer with a maximum rate at 203 and 255 K, respectively. The desorption state at 255 K corresponds to an adsorption energy of 66.0 kJ • mol -1 calculated for a firstorder kinetics with a preexponential factor of 10 13 s -1 . RAIRS suggests that the multilayer and monolayer may be composed of different HOCH 2 CH 2 NH 2 rotational isomers. HOCH 2 CH 2 NH 2 can also decompose on Cu( 100), approximately at the same temperature range of monolayer desorption, mainly to evolve H 2 and H 2 O at ∼400 K. An Ar + -sputtered Cu(100) surface is found to promote the dissociation of HOCH 2 CH 2 NH 2 . Temperature-dependent RAIRS, with the assistance of theoretical calculations based on density-functional theory, strongly suggests that HOCH 2 CH 2 NH 2 on Cu(100) dissociates first by losing a hydrogen atom to form -OCH 2 CH 2 NH 2 , followed by transformation into HOCH 2 CH 2 Nd. Decomposition of the latter species is responsible for the desorption of H 2 and H 2 O.

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Additive manufacturing (AM) is the process of fabricating three-dimensional physical models by layered manufacturing without the need of molds or dies. Surface finish of AM physical models is not satisfactory for most general engineering purposes. The aim of this study is to develop an acetone-vapor polishing system to smooth acrylonitrile butadiene styrene (ABS) parts fabricated by fused deposition modeling. Acetone vapor dissolved the outer surface of ABS parts and the surface roughnesses of ABS parts with complex geometries can be significantly reduced. The advantages of this system include flexibility to maintain dimensional accuracy, high polishing efficiency, low equipment costs, and no waste chemicals compared to conventional approaches.

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Increasing antimicrobial resistance in nontyphoidal Salmonella (NTS) species complicates the use of antibiotics if indicated. We investigated the impact of antimicrobial resistance on clinical outcomes and discussed how to use antibiotics rationally. Hospitalized children in 2005-2006 with stool cultures positive for NTS were identified. The clinical and microbiological features were retrospectively reviewed. A total of 683 children were included [371 (54.3%) male; 89.5% <5 years of age]. Antibiotics were given to 56.5% of the patients; third-generation cephalosporin was the most commonly used drug class. Cases receiving antibiotics that were inactive in vitro did not have more complications than those receiving antibiotics active in vitro. Complications occurred in 7.9% of the patients, with bacteraemia being the most common (57.4%). Compared to the others, patients with longer febrile duration and higher C-reactive protein (CRP) levels (CRP ≥100 mg/L) were more frequently put on empirical antimicrobial therapy and had more complications. These patients usually had shorter hospitalization and duration of fever if antimicrobial agents that can reach high tissue concentrations in the intestinal mucosa were administered, such as fluoroquinolone or ceftriaxone. It is concluded that adequate antibiotics may be clinically beneficial to a subset of patients with high CRP and longer duration of fever among children with NTS enteritis. To prevent the induction of antibiotic resistance from this therapy, we suggested a short course (3-5 days) of intravenous ceftriaxone for such patients, which would lead to a faster clinical recovery.

This study was undertaken to determine whether there was a correlation between fine particles (PM2.5) levels and hospital admissions for myocardial infarction (MI) in Taipei, Taiwan. Hospital admissions for MI and ambient air pollution data for Taipei were obtained for the period 2006-2010. The relative risk of hospital admissions for MI was estimated using a casecrossover approach, controlling for weather variables, day of the week, seasonality, and longterm time trends. For the single-pollutant model (without adjustment for other pollutants), increased numbers of MI admissions were significantly associated with higher PM2.5 levels both on warm days (>23°C) and on cool days (<23°C). This was accompanied by an interquartile range elevation correlated with a 10% (95% CI = 6-15%) and 5% (95% CI = 1-9%) rise in number of MI admissions, respectively. In the two-pollutant models, PM2.5 remained significant after inclusion of SO2 or O3 on both warm and cool days. This study provides evidence that higher levels of PM2.5 increase the risk of hospital admissions for MI.

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