Moments of Gamma type and the Brownian supremum process area

We study positive random variables whose moments can be expressed by products and quotients of Gamma functions; this includes many standard distributions. General results are given on existence, series expansion and asymptotics of density functions. It is shown that the integral of the supremum process of Brownian motion has moments of this type, as well as a related random variable occuring in the study of hashing with linear displacement, and the general results are applied to these variables.Comment: 51 page

Solid state morphology and band gap studies of ETS-10 supported CdS nanoparticles

Engelhard titanosilicate (ETS-10) supported cadmium sulphide (CdS) nanoparticles were synthesized and characterized by various solid state techniques including: XRD, DR UV-Vis, TEM and FESEM. The effect of different synthesis routes of CdS nanoparticles on its physicochemical character was studied. It was observed that CdS nanoparticles prepared by both in situ sulphur reduction (CdS-IS) and reverse micelle (CdS-RM) methods showed similar properties. However, CdS-IS nanoparticles are more feasible and economically practical. The reflectance measurements of the as-synthesized CdS nanoparticles are apparently blue-shifted compared to bulk CdS. This phenomenon of blue-shifted absorption edge has been ascribed to an increase in bandgap energy with a decrease in particle sizes. The bandgap of the as-synthesized CdS samples was calculated from the linear correlation of [F(R) h?]2 and h?. The bandgap of CdS in ETS-10 was noticeably slightly reduced when compared with the as-synthesized CdS (8 nm) due to the formation of cluster arrays on the pores of ETS-10

Effects of the preparation method of the ternary CdS/TiO_2/Pt hybrid photocatalysts on visible light-induced hydrogen production

A variety of combinations of CdS, TiO2, and Pt in preparing the hybrid catalysts were studied for hydrogen production under visible light ( > 420 nm) irradiation. The preparation method sensitively influenced the activity of the ternary hybrid catalysts. The formation of the potential gradient at the interface between CdS and TiO2 is necessary in achieving the efficient charge separation and transfer and how the platinum as a cocatalyst is loaded onto the CdS/TiO2 hybrid catalysts determines the overall hydrogen production efficiency. The common method of photoplatinization of CdS/TiO2 hybrid [Pt-(CdS/TiO2)] was much less efficient than the present method in which Pt was photodeposited on bare TiO2, which was followed by the deposition of CdS [CdS/(Pt-TiO2)]. The CdS/(Pt-TiO2) has the hydrogen production rate ranging (6–9) × 10-3 mol h-1 g-1, which is higher by a factor of 3–30 than that of Pt-(CdS/TiO2). The photocatalytic activity of the ternary hybrid catalysts was extremely sensitive to where the platinum is loaded. The photoactivity of the hybrid catalyst was also assessed in terms of the photocurrent collected by the methyl viologen electron shuttle in the catalyst suspension. CdS/(Pt-TiO2) generated higher photocurrents than Pt-(CdS/TiO2) by a factor of 2–7. The extreme sensitivity of the preparation method to the hydrogen production activity should be taken into account when hybrid photocatalysts are designed and prepared

Preparation of N-doped carbon dots based on starch and their application in white LED

N-doped carbon dots (CDs) were synthesized simply and economically by a one-step hydrothermal method using starch as a carbon source and ethylenediamine (EDA) as a nitrogen dopant. The prepared CDs possess the properties of excitation-wavelength dependence and emit blue fluorescence under the excitation wavelength of 365 nm. CDs/starch composite was prepared to achieve the solid-state emission of CDs and their application in light emitting diode (LED) as fluorescent materials. White LED, with CIE coordinates of (0.33, 0.37) and correlated color temperature of 5462 K, was obtained by combining CDs/starch and ultraviolet LED light source, indicating that starch-based CDs have the promising potential in the field of optoelectronic devicesPeer reviewe

A conceptual framework and protocol for defining clinical decision support objectives applicable to medical specialties.

BackgroundThe U.S. Centers for Medicare and Medicaid Services established the Electronic Health Record (EHR) Incentive Program in 2009 to stimulate the adoption of EHRs. One component of the program requires eligible providers to implement clinical decision support (CDS) interventions that can improve performance on one or more quality measures pre-selected for each specialty. Because the unique decision-making challenges and existing HIT capabilities vary widely across specialties, the development of meaningful objectives for CDS within such programs must be supported by deliberative analysis.DesignWe developed a conceptual framework and protocol that combines evidence review with expert opinion to elicit clinically meaningful objectives for CDS directly from specialists. The framework links objectives for CDS to specialty-specific performance gaps while ensuring that a workable set of CDS opportunities are available to providers to address each performance gap. Performance gaps may include those with well-established quality measures but also priorities identified by specialists based on their clinical experience. Moreover, objectives are not constrained to performance gaps with existing CDS technologies, but rather may include those for which CDS tools might reasonably be expected to be developed in the near term, for example, by the beginning of Stage 3 of the EHR Incentive program. The protocol uses a modified Delphi expert panel process to elicit and prioritize CDS meaningful use objectives. Experts first rate the importance of performance gaps, beginning with a candidate list generated through an environmental scan and supplemented through nominations by panelists. For the highest priority performance gaps, panelists then rate the extent to which existing or future CDS interventions, characterized jointly as "CDS opportunities," might impact each performance gap and the extent to which each CDS opportunity is compatible with specialists' clinical workflows. The protocol was tested by expert panels representing four clinical specialties: oncology, orthopedic surgery, interventional cardiology, and pediatrics

The GUIDES checklist: development of a tool to improve the successful use of guideline-based computerised clinical decision support

Background: Computerised decision support (CDS) based on trustworthy clinical guidelines is a key component of a learning healthcare system. Research shows that the effectiveness of CDS is mixed. Multifaceted context, system, recommendation and implementation factors may potentially affect the success of CDS interventions. This paper describes the development of a checklist that is intended to support professionals to implement CDS successfully. Methods: We developed the checklist through an iterative process that involved a systematic review of evidence and frameworks, a synthesis of the success factors identified in the review, feedback from an international expert panel that evaluated the checklist in relation to a list of desirable framework attributes, consultations with patients and healthcare consumers and pilot testing of the checklist. Results: We screened 5347 papers and selected 71 papers with relevant information on success factors for guideline-based CDS. From the selected papers, we developed a 16-factor checklist that is divided in four domains, i.e. the CDS context, content, system and implementation domains. The panel of experts evaluated the checklist positively as an instrument that could support people implementing guideline-based CDS across a wide range of settings globally. Patients and healthcare consumers identified guideline-based CDS as an important quality improvement intervention and perceived the GUIDES checklist as a suitable and useful strategy. Conclusions: The GUIDES checklist can support professionals in considering the factors that affect the success of CDS interventions. It may facilitate a deeper and more accurate understanding of the factors shaping CDS effectiveness. Relying on a structured approach may prevent that important factors are missed

“Does the tail wag the dog? The effect of credit default swaps on credit risk”

Credit default swaps (CDS) are derivative contracts that are widely used as tools for credit risk management. However, in recent years, concerns have been raised about whether CDS trading itself affects the credit risk of the reference entities. We use a unique, comprehensive sample covering CDS trading of 901 North American corporate issuers, between June 1997 and April 2009, to address this question. We find that the probability of both a credit rating downgrade and bankruptcy increase, with large economic magnitudes, after the inception of CDS trading. This finding is robust to controlling for the endogeneity of CDS trading. Beyond the CDS introduction effect, we show that firms with relatively larger amounts of CDS contracts outstanding, and those with relatively more “no restructuring” contracts than other types of CDS contracts covering restructuring, are more adversely affected by CDS trading. Moreover, the number of creditors increases after CDS trading begins, exacerbating creditor coordination failure for the resolution of financial distress