Hospitalized self-inflicted firearm injuries have not been extensively studied, particularly regarding clinical diagnoses at the index admission. The objective of this study was to discover the diagnostic phenotypes (DPs) or clusters of hospitalized self-inflicted firearm injuries. Using Nationwide Inpatient Sample data in the US from 1993 to 2014, we used International Classification of Diseases, Ninth Revision codes to identify self-inflicted firearm injuries among those ≥18 years of age. The 25 most frequent diagnostic codes were used to compute a dissimilarity matrix and the optimal number of clusters. We used hierarchical clustering to identify the main DPs. The overall cohort included 14072 hospitalizations, with self-inflicted firearm injuries occurring mainly in those between 16 to 45 years of age, black, with co-occurring tobacco and alcohol use, and mental illness. Out of the three identified DPs, DP1 was the largest (n=10,110), and included most common diagnoses similar to overall cohort, including major depressive disorders (27.7%), hypertension (16.8%), acute post hemorrhagic anemia (16.7%), tobacco (15.7%) and alcohol use (12.6%). DP2 (n=3,725) was not characterized by any of the top 25 ICD-9 diagnoses codes, and included children and peripartum women. DP3, the smallest phenotype (n=237), had high prevalence of depression similar to DP1, and defined by fewer fatal injuries of chest and abdomen. There were three distinct diagnostic phenotypes in hospitalizations due to self-inflicted firearm injuries. Further research is needed to determine how DPs can be used to tailor clinical care and prevention efforts.
The present study compared motivations to enter the teaching profession between native and nonnative pre-service Chinese as a second/foreign language (CSL/CFL) teachers. The participants included 325 native and 325 nonnative Chinese-speaking pre-service CSL/CFL teachers registered in Masters in Teaching Chinese to Speakers of Other Languages (MTCSOL) programmes; the teachers were asked to complete a 24-item questionnaire. Two major findings emerged. First, a similar six-factor teacher motivation were observed for the native and nonnative teachers. Second, the two groups showed nonsignificant differences in their ratings of the importance of cross-cultural value, intrinsic value, altruistic value and fallback career choice as types of motivation but differed significantly in their ratings of extrinsic value and social influence. These results highlight the differences and similarities in second language teacher motivation and offer insights into the variables at different levels that might influence second language teacher motivation. Teacher motivation is advised to be taken into account in the training and administration of CSL/CFL teachers to alleviate the problem of teacher shortage outside China.
We systematically investigate ellipticity dependence of high-order harmonic generation of Ar and N2 in intense elliptically polarized laser fields. The experimental normalized ratios of low-order harmonic intensity to high-order harmonic intensity increase with ellipticity for both Ar and N2, and quantitatively depend on targets and trajectory paths. The experimental results are well reproduced by a nonadiabatic semiclassical simulation and explained by trajectory-based analysis. In addition, the influence of nuclear distance on the ratios is theoretically investigated. Our work reveals that the difference between atoms and molecules can be attributed to the influence of different ionic potentials, which depends on the molecular structure (internuclear distance) and alignment, on the evolution of the photoelectron.
Why are organizations sometimes so similar, and in other cases so different? For decades this question has been central to research on organizations, and two leading theories have answered the question very differently. Neo-institutional theory has pointed to the importance of mimetic isomorphism, where organizations imitate one another as they navigate decisions in the context of uncertainty over what is regarded as legitimate action. By contrast, ecological theory argues that competitive exclusion explains the differences we see around us, as organizations repel one another when they vie for the same resources. Decades of empirical work has tended to confirm one or the other theory, with scant effort being made to reconcile these conflicting predictions. Furthermore, much of the existing empirical work is limited to descriptive studies that make little or no attempt to empirically identify their findings, leaving the empirical record open to concerns over endogeneity. This paper conducts an identified empirical test, in a context where the two arguments make opposing predictions. In an analysis of auditor selection after the collapse of Arthur Andersen, we find evidence of competitive exclusion, but no evidence of mimetic isomorphism. Implications for the continued progress of organization theory are discussed.