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Focused ion beam and scanning electron microscope (FIB-SEM) instruments are extensively used to characterize nanoscale composition of composite materials, however, their application to analysis of organic corrosion barrier coatings has been limited. The primary concern that arises with use of FIB to mill organic materials is the possibility of severe thermal damage that occurs in close proximity to the ion beam impact. Recent research has shown that such localized artefacts can be mitigated for a number of polymers through cryogenic cooling of the sample as well as low current milling and intelligent ion beam control. Here we report unexpected nonlocalized artefacts that occur during FIB milling of composite organic coatings with pigment particles. Specifically, we show that FIB milling of pigmented polysiloxane coating can lead to formation of multiple microscopic voids within the substrate as far as 5 µm away from the ion beam impact. We use further experimentation and modelling to show that void formation occurs via ion beam heating of the pigment particles that leads to decomposition and vaporization of the surrounding polysiloxane. We also identify FIB milling conditions that mitigate this issue.
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BACKGROUND AND AIMS: Electrical burns are uncommon, but they result in high morbidity and mortality due to severe tissue damage. The purpose of this study is to analyze epidemiological variables of electrical injuries and identify preventable measures through them. MATERIAL AND METHODS: We retrospectively analyzed the clinical records of 625 patients admitted to Hangang Sacred Heart Hospital's Department of Plastic Surgery from January 2005 to December 2011. We divided the patients into two groups: (1) low-voltage injury (under 1000 V) and (2) high-voltage injury (over 1000 V). We reviewed the following variables: age, sex, total burn surface area, injury type and mode, and surgical modalities. RESULTS AND CONCLUSIONS: The mean age of all patients was 33.4 ± 18.2 years. The ratio of males to females was 13.5 in the whole group. The mean total body surface are burned was 14.0% ± 13.8% in total. The majority of electrical burns in the low-tension group and high-tension group occurred in patients under 20 years and in patients aged 40-59 years, respectively. Steel chopstick insertions and high-voltage electrical work/repair were the most common injury modes in the low-tension group and the high-tension group, respectively. Groin and abdominal distant flap surgeries were commonly performed in both groups. It is recommended that these risks be prevented through education and safety measures to reduce the incidence of electrical injuries.
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Quemaduras por Electricidad/epidemiología , Procedimientos de Cirugía Plástica/métodos , Colgajos Quirúrgicos , Adolescente , Adulto , Anciano , Quemaduras por Electricidad/diagnóstico , Quemaduras por Electricidad/cirugía , Niño , Preescolar , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , República de Corea/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Índices de Gravedad del Trauma , Adulto JovenRESUMEN
1. Two experiments were conducted to evaluate a multi-microbe probiotic formulation processed at low (LT) or high (HT) drying temperature. 2. In both the experiments, 640 d-old Ross male chicks were randomly allotted to 4 treatments on the basis of initial BW for 35 d experiments. 3. In experiment one, dietary treatments were a negative control (NC; basal diet without any antimicrobial); positive control (PC; basal diet +10 mg/kg avilamycin); basal diet with 0·3% probiotic LT; and basal diet with 0·3% probiotic HT. 4. Improved overall weight gain, FCR and retention of CP were observed in birds fed the PC and probiotic diets when compared with birds fed the NC diet. At d 21, birds fed the probiotic and NC diets had more caecal Bifidobacterium and total anaerobes than birds fed the PC diet; while birds fed the PC and probiotic diets had fewer caecal Clostridium than birds fed the NC diet at d 35. 5. In experiment two, a 2 × 2 factorial arrangement of treatments was employed to evaluate the effects of two concentrations of probiotic HT (0·30 or 0·60%) and avilamycin (0 or 10 mg/kg). 6. Birds fed the 0·60% probiotic HT diet showed improved overall weight gain and CP retention, higher Lactobacillus and Bifidobacterium in the caecum, and reduced Clostridium and coliforms in the caecum. Inclusion of avilamycin improved the overall weight gain and feed intake, and reduced the caecal Clostridium and Bifidobacterium population. 7. In conclusion, high drying temperature had no effect on the efficacy of the multi-microbe probiotic formulation; while the probiotic HT formulation was more effective at the 0·60% level. Moreover, inclusion of avilamycin improved performance of birds but did not have any interaction with probiotics.
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Antibacterianos/farmacología , Ciego/microbiología , Pollos/fisiología , Digestión , Oligosacáridos/farmacología , Alimentación Animal/microbiología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Pollos/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Fermentación , Masculino , Probióticos/administración & dosificación , Probióticos/farmacología , TemperaturaRESUMEN
Gold nanoparticles (Au NPs) were directly synthesized on the surface of polyvinylsilazane (PVSZ, -[(vinyl)SiH-NH2]-) without use of extra reductive additives. The reductive Si-H functional groups on the surface of cured PVSZ acted as surface bound reducing agents to form gold metal when contacted with an aqueous Au precursor (HAuCl4) solution, leading to formation of Au NPs adhered to silicate glass surface. The Au NPs-silicate platforms were preliminarily tested to detect Rhodamine B (1 µM) by surface enhanced Raman scattering. Furthermore, gold microelectrode obtained by post-chemical plating was used as an integrated amperometric detection element in the polydimethylsilane-glass hybrid microfluidic chip.
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PURPOSE: To assess the therapeutic effect and toxicity of intravenous colistin in the treatment of multidrug-resistant (MDR) Gram-negative bacteria in patients with severe burns. METHODS: The medical records of 930 patients admitted to the Burn Intensive Care Unit (ICU) at Hallym University Hangang Sacred Heart Hospital, Seoul, South Korea between April 2007 and December 2009 were retrospectively reviewed. Of these, the 104 patients who had received intravenous colistin treatments (104 courses) during this period were enrolled in the study. Changes in creatinine level were analyzed in three groups: all patients receiving colistin (n = 104), patients with undergoing continuous renal replacement therapy (CRRT group; n = 38), and patients not undergoing CRRT (non-CRRT group; n = 66). RESULTS: Among these patients, the burnt body surface area ranged from 5 to 96% (mean 49.7%). Thirty-five patients (33.7%) suffered inhalation injury, and CRRT was administered to 38 patients. The mean duration of colistin treatment was 14.7 (range 4-71) days. The total dose of colistin was 3,045.7 mg (range 100-13,800). The length of ICU stay was 48.9 (range 7-154) days. Forty patients (38.5%) died. The mean pre-colistin creatinine level of all patients was 1.04 mg/dL, and the mean post-colistin level was 1.34 mg/dL. The mean pre-colistin creatinine level of the CRRT group and non-CRRT group was 1.68 and 0.66 mg/dL, and the mean post-colistin level was 1.68 and 1.14 mg/dL, respectively. CONCLUSIONS: Colistin appears to be a relatively safe and effective treatment for major burn patients with infections caused by MDR Gram-negative bacteria when no other drug is available. Additionally, we found no statistically significant impairment of creatinine levels.
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Infecciones por Acinetobacter/tratamiento farmacológico , Antibacterianos/uso terapéutico , Quemaduras/tratamiento farmacológico , Colistina/uso terapéutico , Farmacorresistencia Bacteriana Múltiple , Infecciones por Pseudomonas/tratamiento farmacológico , Acinetobacter/aislamiento & purificación , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/mortalidad , Adulto , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Unidades de Quemados , Quemaduras/sangre , Quemaduras/microbiología , Quemaduras/mortalidad , Niño , Colistina/administración & dosificación , Creatinina/sangre , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Pseudomonas/aislamiento & purificación , Infecciones por Pseudomonas/microbiología , Infecciones por Pseudomonas/mortalidad , Terapia de Reemplazo Renal , República de Corea , Estudios Retrospectivos , Adulto JovenRESUMEN
The new title compound has been synthesized and characterized by physical property measurements and electronic structure calculations. The results ratify the highly uncommon deficiency of one electron that has been long speculated for its Ca3Ga5-type structure on the basis of the simple Zintl electron counting formalism. In the Sr3In5 structure (Cmcm), 4- and 2-bonded indium atoms in a 4:1 ratio form a three-dimensional classical network that encapsulates strontium atoms in its narrow channels. The electrical conductivity of the compound shows typical metallic behavior. The detailed electronic structure analysis suggests that the electron hole is mainly localized on a nonbonding p-orbital on the 2-bonded indium atoms, and that these orbitals, stacked in a sigma-type way along avector (4.97 A), interact only weakly with each other to form highly one-dimensional bands.
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Tight-binding electronic band structures of cesium trihalometalates CsGeX(3) (X = Cl, Br) were calculated to examine the pressure-dependence of their crystal structures and band gaps as well as their primitive cubic to rhombohedral structural phase transitions. In agreement with experiment, our calculations show that an increase in the applied pressure decreases the band gap and the stability of CsGeX(3), and the band gap is larger for CsGeCl(3) than for CsGeBr(3). CsGeCl(3) has a much stronger second-order Jahn-Teller instability than does CsGeBr(3) and therefore can adopt a disordered cubic phase unlike CsGeBr(3).
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Tight-binding electronic band structures and Madelung potentials were calculated for La(2)NiO(4), La(3)Ni(2)O(7), and La(4)Ni(3)O(10) to examine why a metal-to-metal transition occurs in the nickelate Ln(4)Ni(3)O(10) (Ln = La, Nd, Pr). La(4)Ni(3)O(10) and La(3)Ni(2)O(7) are each found to have two hidden one-dimensional (1D) Fermi surfaces, which suggests that both compounds should possess a charge density wave instability. Factors leading to hidden 1D Fermi surfaces in the e(g) block bands of the nickelates were discussed.