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In the existing papers considering the stability analysis of discrete-time systems with distributed delays via the Lyapunov-Krasovskii functional (LKF) method, the delay kernels are normally restricted to be non-negative. In this paper, we aim to remove such a restriction and deal with the stability analysis of systems with arbitrary delay kernels. For this purpose, a kernel-related summation inequality is first constructed. Then, a stability condition is derived based on the proposed inequality and a model transformation. Finally, two numerical examples are presented to show that the proposed stability condition not only has a wider scope of application and is less conservative than the existing ones. [ABSTRACT FROM AUTHOR]

Triaging patients into correct severity categories in an emergency department is an advanced skill that depends on a quick assessment after obtaining very little information. The purpose of this study was to assess specific risk factors associated with hospital admissions in the emergency department environment of the specialized Eye, Ear, Nose, and Throat hospital located in Shanghai, China. This study was a retrospective cohort study. Patients visiting the emergency department in a tertiary hospital in eastern China from February 2008 to August 2015 were included. Univariate and multivariate analyses were used to identify the risk factors related to hospital admissions. Combining variables calculated from the regression equation of multivariate analysis (binary logistic regression analysis) enabled the risk factors quantification. The receiver operating characteristic analysis was used to identify the most informative cutoff point of the combining predictors. A total of 188715 patients were enrolled in the study. Of them, 8395 patients (4.4%) required hospital admission. Hour of visit, season, age, sex, chief complaint, anatomical location, and locale of patients were independent risk factors of hospital admission by univariate and multivariate analysis. Combining predictors were calculated from the equation of the multivariate logistic model. The area under the curve of the combining predictors was 0.949, and the 95% confidence interval was 0.947 to 0.951 (P <.001), with a sensitivity of 95.2% and a specificity of 85.6%. A cutoff score of less than –35.1975 was associated with hospital admission. This study provided a method to build a feasible predictive model of hospital admission during triage. Understanding risk factors is an important part of the triage process in order to correctly assign priorities to the patients served. The outcomes of this study would add additional information for the triage nurse to consider in assessing the patient and assigning acuity ratings. The model developed here requires validation in future research. [ABSTRACT FROM AUTHOR]

In this paper, a Bessel-type inequality in semi-inner produce (s.i.p.) spaces is presented to deal with the problem of stability analysis for a class of discrete-time systems with distributed delays. The main purpose of this paper is to obtain less conservative stability conditions for the investigated systems. For this purpose, a novel inequality (which is referred to as Bessel-type inequality in s.i.p. spaces) is constructed by combining the Bessel inequality and a set of polynomials which is pairwise orthogonal in a s.i.p. space. The proposed inequality is more general than the conventional Jensen-type inequality, which is, to the best of our knowledge, the only inequality to deal with the problem of stability analysis for discrete-time systems with distributed delays up to now. Based on the proposed inequality and the Lyapunov-Krasovskii stability theory, a stability condition is presented. Finally, a numerical example is given to indicate that the proposed method is able to effectively reduce the conservatism. [ABSTRACT FROM AUTHOR]

Abstract: As a kind of organocatalyst, 1-[4-(perfluorooctyl)phenyl]-3-phenylthiourea was employed to the chemoselective oxidation of sulfides in the presence of 30% H2O2. A variety of diaryl, dialkyl, alkyl aryl sulfides could be oxidized to sulfoxide under the mild condition. The catalyst could be easily recovered by fluorous solid-phase extraction for reuse. [Copyright &y& Elsevier]

Abstract: A commercially available perfluorooctyl aniline and phenyl isothiocyanate were reacted under mild conditions to give 1-[4-(perfluorooctyl)phenyl]-3-phenylthiourea as an analogue of thiourea-based organocatalyst. This fluorous organocatalyst was successfully employed to direct reductive amination of aldehydes. It could be readily separated from reaction product by fluorous solid phase extraction for direct use. [Copyright &y& Elsevier]

• The first report of direct reprogramming fibroblast into inner ear HC lineage. • The current approach is characterized by cell activation and signal direction. • Adult endogenous fibroblast as the reprogramming object is promising in medicine. • There are barriers in adult fibroblast to resist a radical cell fate change. • Activation of FGF signal path is important for the conversion to HC lineage. Loss of inner ear hair cell (HC) is an irreversible process in mammals and is the most common cause of human hearing and balance disorders especially in the elderly. Cell therapy based on highly scalable generation of HC linage and inner ear transplantation is one of the most promising therapeutic approaches for HC impairment. For fibroblast is quite abundant and readily available in human body, it is an ideal endogenous cell source to generate HC lineage for transplantation purpose. In the present study, by using a cell activation and signaling directed method, we demonstrate that adult fibroblast can be direct reprogrammed into a kind of cell which expresses lots of HC markers. At the same time, an intermediate progenitor stage exists during such a lineage conversion and activation of FGF pathway is critical for its formation. Although these reprogrammed cells still lack some of the key features of HC such as mechanosensitive ion channel hence have not acquired the functional properties of HC, the findings reported here raise the possibility of reprogramming endogenous fibroblasts into functional HC for regenerative purpose. [ABSTRACT FROM AUTHOR]

• C(sp2)–H bond activation reactions of N -(hetero)aryl-7-azaindoles. • Cross-coupling with α-carbonyl sulfoxonium ylides. • High regioselectivity. • Excellent chemical yields and good functional group tolerance. We described a protocol for rhodium-catalyzed C(sp2)–H bond activation reactions of N- (hetero)aryl-7-azaindoles and cross-coupling with α-carbonyl sulfoxonium ylides. In the C–H activation reaction, the 7-azaindole moiety acts as a directing group, which results in high regioselectivity. The protocol features excellent chemical yields and good functional group tolerance. [ABSTRACT FROM AUTHOR]