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The chemical and phase composition of the coating and the coating/substrate interface of an Al-Si-coated 22MnB5 hot stamped steel was investigated by means of SEM-EDS, XRD, micro-XRD and electron diffraction. Moreover, the surface profile was analyzed by XPS and roughness measurements. The XPS measurements showed that the thickness of the Si and Al oxide layers increased from 14 to 76 nm after die-quenching, and that the surface roughness increased as well as a result of volume changes caused by phase transformations. In addition to the FeAl(Si) and Fe2Al5 phases and the interdiffusion layer forming complex structures in the coating, electron diffraction confirmed the presence of an Fe2Al5 phase, and also revealed very thin layers of Fe3(Al,Si)C, Fe2(Al,Si)5 and Al-bearing rod-shaped particles in the immediate vicinity of the steel interface. Moreover, the scattered nonuniform layer of the Fe2Al8Si phase was identified in the outermost layer of the coating. Despite numerous studies devoted to researching the phase composition of the Al-Si coating applied to hot stamped steel, electron diffraction revealed very thin layers and particles on the coating/substrate interface and outermost layer, which have not been analyzed in detail.  相似文献   
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Objectives: This study aims to describe frequent users of Emergency Medical Services (EMS) conveyed to a Singapore tertiary hospital, focusing on a comparison between younger users (age <65) and older users in diagnoses and admission rates. Methods: All patients conveyed by EMS to a tertiary hospital 4 times or more over a 1-year period in 2015 had their EMS ambulance charts and Emergency Department (ED) electronic records retrospectively analyzed (n?=?243), with admission the primary outcome. Results: The 243 frequent users were analyzed with a combined total of 1,705 visits, out of a total of 10,183 patients with 12,839 visits conveyed by EMS to Singapore General Hospital (SGH) in 2015. Younger frequent users (<65 years age) were found to be predominantly male (79.6%, p?=?0.001) and were on average responsible for more visits than elderly frequent users (8.6 vs. 5.7, p?=?0.004). Medical co-morbidities were significantly more prevalent in older users. Younger frequent users were more likely to be smokers (60.2% vs. 22.3%), heavy drinkers (51.3% vs. 8.5%), substance abusers (12.4% vs. 0.8%), and bad debtors (49.6% vs. 20.0%, p?<?0.001). A larger proportion presented with altered mental states (11.7% vs. 5.4%, p?<?0.001) and alcohol related diagnoses (34.7% vs. 5.3%, p?<?0.001). Many were picked up from public areas (45.5% vs. 19.6%, p?<?0.001), and had lower acuity triage scores at both EMS (p?<?0.001) and ED (p?=?0.001). They had lower admission rates (40.5% vs. 78.7%, p?<?0.001) and shorter length of stay (4.3 vs. 5.9 days, p?<?0.001). Univariable and multivariable analysis showed alcohol related diagnoses, history of alcohol abuse and lower triage scores were less likely to require admissions. Conclusion: Frequent EMS users consume a disproportionate amount of healthcare resources. Two broad subgroups of patients were identified: younger patients with social issues and older patients with multiple medical conditions. EMS usage by older patients was significantly associated with higher rates of admission  相似文献   
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Rates of relapse in BD are high with medication nonadherence identified as an important contributor to relapse. Psychopharmacology remains a key component to the treatment of BD; therefore, increased understanding of medication use and ways to promote greater adherence is essential. The aim of the study was to identify how participants with BD experience taking prescribed medication. Participants had BD I or BD II, were users of specialist mental health services, aged 18–64 years, euthymic, mildly hypomanic or depressed, and on any combination of medication. Exclusion criteria were minimal. A semistructured interview was completed exploring patients’ views of BD and factors influencing adherence based on the Subjective Experience of Medication Interview. An inductive thematic analysis was used to identify themes. The study participants (n = 36) had predominantly bipolar I (78%) and were female (69%), and of New Zealand European ethnicity (67%) with 14% Maori. The mean age was 41 years (SD: 12.0). Findings from the thematic analysis generated three themes: Learning about the clinical meaning of having BD, Understanding how to use medication, and Understanding what works for me. The qualitative nature of our study limits the generalizability of our findings to a broader population of individuals with BD. The participants developed confidence in being in charge of their BD through a process of learning about BD and medication and understanding what this meant for them. The findings support greater emphasis on collaborative approaches that recognize the expertise of the individual with BD and the clinician.  相似文献   
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