Matrix continued fractions and Expansions of the Error Function

In this paper we recall some results and some criteria on the convergence of matrix continued fractions. The aim of this paper is to give some properties and results of continued fractions with matrix arguments. Then we give continued fraction expansions of the error function erf(A) where A is a matrix. At the end, some numerical examples illustrating the theoretical results are discussed

Effect of Mn Doped and Mn+Sn Co-doping on the Properties of ZnO Thin Films

Mn doped and Mn/Sn co-doped ZnO thin films nanoparticles have been successfully synthesized by Spray pyrolysis technique at 300 0C. X-ray diffraction study showed that all the films have the hexagonal wurtzite structure with the preferential orientation (002) plane. The optical measurement exhibited an increase in the average transmittance from 77% for Mn doped ZnO to 84% for Mn/Sn co-doped ZnO films in the visible region. Further the optical band gap changes from 3.18 eV for undoped ZnO films to 3.27 eV for Mn/Sn co-doped ZnO films. The electrical resistivity has decreased with incorporation of Mn and Sn ions to reach the minimum value of 11 (Ω.cm) for Mn doped ZnO film

PREDICTING PERCEIVED COMPLEXITY USING LOCAL CONTRAST STATISTICS AND FRACTAL INFORMATION

This study aims to explore visual complexity in streetscape composition using RMS contrast information and Fractal Analysis. The dataset was composed of 74 streetscape images, taken in Algeria and Japan in daytime and nighttime. The evaluation and analysis covered two phases: (1) Subjective quantification of perceived complexity using ranking method. (2) Visual complexity measurement based on RMS contrast statistics and fractal characteristics of the streetscape images. The results showed a positive correlation between the subjective ranking of complexity in streetscape images and the proposed measure of visual complexity “α” as well as with the fractal dimension D

A multi-country test of brief reappraisal interventions on emotions during the COVID-19 pandemic

The COVID-19 pandemic has increased negative emotions and decreased positive emotions globally. Left unchecked, these emotional changes might have a wide array of adverse impacts. To reduce negative emotions and increase positive emotions, we tested the effectiveness of reappraisal, an emotion-regulation strategy that modifies how one thinks about a situation. Participants from 87 countries and regions (n = 21,644) were randomly assigned to one of two brief reappraisal interventions (reconstrual or repurposing) or one of two control conditions (active or passive). Results revealed that both reappraisal interventions (vesus both control conditions) consistently reduced negative emotions and increased positive emotions across different measures. Reconstrual and repurposing interventions had similar effects. Importantly, planned exploratory analyses indicated that reappraisal interventions did not reduce intentions to practice preventive health behaviours. The findings demonstrate the viability of creating scalable, low-cost interventions for use around the world

Protective intraoperative ventilation with higher versus lower levels of positive end-expiratory pressure in obese patients (PROBESE): study protocol for a randomized controlled trial

Background: Postoperative pulmonary complications (PPCs) increase the morbidity and mortality of surgery in obese patients. High levels of positive end-expiratory pressure (PEEP) with lung recruitment maneuvers may improve intraoperative respiratory function, but they can also compromise hemodynamics, and the effects on PPCs are uncertain. We hypothesized that intraoperative mechanical ventilation using high PEEP with periodic recruitment maneuvers, as compared with low PEEP without recruitment maneuvers, prevents PPCs in obese patients. Methods/design The PRotective Ventilation with Higher versus Lower PEEP during General Anesthesia for Surgery in OBESE Patients (PROBESE) study is a multicenter, two-arm, international randomized controlled trial. In total, 2013 obese patients with body mass index ≥35 kg/m2 scheduled for at least 2 h of surgery under general anesthesia and at intermediate to high risk for PPCs will be included. Patients are ventilated intraoperatively with a low tidal volume of 7 ml/kg (predicted body weight) and randomly assigned to PEEP of 12 cmH2O with lung recruitment maneuvers (high PEEP) or PEEP of 4 cmH2O without recruitment maneuvers (low PEEP). The occurrence of PPCs will be recorded as collapsed composite of single adverse pulmonary events and represents the primary endpoint. Discussion To our knowledge, the PROBESE trial is the first multicenter, international randomized controlled trial to compare the effects of two different levels of intraoperative PEEP during protective low tidal volume ventilation on PPCs in obese patients. The results of the PROBESE trial will support anesthesiologists in their decision to choose a certain PEEP level during general anesthesia for surgery in obese patients in an attempt to prevent PPCs. Trial registration ClinicalTrials.gov identifier: NCT02148692. Registered on 23 May 2014; last updated 7 June 2016. Electronic supplementary material The online version of this article (doi:10.1186/s13063-017-1929-0) contains supplementary material, which is available to authorized users

Molarities Effect on Structural Optical and Electrical Properties of Nanostructured Zinc Oxide deposited by Spray Pyrolysis Technique

ZnO thin film were synthesized by spray pyrolysis on glass substrates, using zinc chloride as precursor with different molarities 0.05M,0.1M and 0.15 M. The XRD patterns showed that the films deposited are polycrystalline with hexagonal structure and a preferred orientation of the along (002) plane. Increasing of solution molarity caused the increase the crystallite size of the films from37.01nm for 0.05M to 45.79 for 0.1M and it is slightly reduced for 0.15M. XPS studies indicates clearly the formation of the ZnO films. The optical study showed that the average transmittance enhancement when the molarity increases and reaches the maximum of about 80% for 0.1M. Further it exhibits increase in the optical band gap from 2.71 eV to 3.04 eV as the molarity increment. The room temperature electrical resistivity of ZnO films decreases when the molarity increases and reaches the optimum value of 1.92 × 10+2 (Ωcm) for 0.1

Tco’s Thin Films Grown By Spray Pyrolysis Technique For Window Layer Of Solar Cell Application: A Comparative Study

Thin films of ZnO, SnO2 and CdO have been deposited using spray pyrolysis technique. They were characterized by X-Ray diffraction (XRD), optical absorption in the wavelength range 200-2500 nm and Hall Effect measurements. A comparative study was conducted for the prepared TCO’s thin films. The structural studies revealed the formation of polycrystalline thin films with a hexagonal wurtzite and tetragonal rutile structure for ZnO and SnO2 thin films respectively, whereas a cubic structure was found for the CdO films. Optical studies showed that the prepared SnO2, ZnO and CdO thin films had a direct band gap of 3.72, 2.98 and 2.43 eV, respectively. The ZnO films exhibited highest optical transmittance that varied between 70% - 88%. The film thickness of the samples was estimated from transmission spectra. The effective mass of the carriers (m*) at the Fermi level and the figure of merit of the deposited films are also investigated. Hall Effect measurements confirm the n-type nature of the TCO’s thin films. A low resistivity in the order of 10-2 (Ω.cm) has been observed for SnO2 and CdO thin films