Reliability evaluation of m-consecutive- k, l-out-of-n: F system subjected to shocks

In this paper, we propose a shock model for an m-consecutive- k, l-out-of- n: F system. This paper presents a reliability analysis of an m-consecutive- k, l-out-of- n: F system subjected to shocks that destroy a random number of components. One of the main random variables is the number of components affected by successive shocks. Phase-type distributions have been used to model the intervals between successive shocks. The main objective of this study is to show how phase-type distributions can be used to determine the reliability of m-consecutive- k, l-out-of- n: F systems subjected to shocks, which destroy a random number of components. Consideration is given to the optimal replacement time problem, which addresses the minimization of the total long-run average cost per unit time.

Privacy-preserving audit and feedback on the antibiotic prescribing of General Practitioners (Preprint)

BACKGROUND Antibiotic resistance is a worldwide public health problem that is accelerated by misuse and overuse of antibiotics. Studies have shown that audit and feedback enabling clinicians to compare their clinical performance with their peers is effective in reducing inappropriate prescribing of antibiotics. However, privacy concerns make the audit and feedback hard to implement in clinical settings. Therefore, we have developed a privacy-preserving audit and feedback (A&F). OBJECTIVE The paper aims to evaluate the privacy-preserving audit and feedback (A&F) system in clinical settings. METHODS A privacy-preserving A&F system was deployed in three primary care practices in Norway to generate feedback to twenty General Practitioners (GPs) on their prescribing of antibiotics for selected respiratory tract infections. The GPs were asked to participate in a survey shortly after using the system, and we analysed the data. RESULTS Fourteen GPs responded to the questionnaire, representing a 70% (14/20) response rate. The participants were generally satisfied with usefulness of the feedback and the comparison with peers, as well as protection of privacy. The majority of the GPs value the protection of their own privacy, as well as that of their patients. CONCLUSIONS The system overcomes important privacy and scaling challenges commonly associated with secondary use of electronic health record (EHR) data, and has a potential to improve antibiotic prescribing behaviour; however, further study is required to assess its actual effect.

Peptides affecting outer membrane lipid asymmetry (MlaA-OmpC/F) system reduce avian pathogenic Escherichia coli (APEC) colonization in chickens

Avian pathogenic E. coli (APEC), an extra-intestinal pathogenic E. coli (ExPEC), causes colibacillosis in chickens and is reportedly associated with urinary tract infections and meningitis in humans. Development of resistance is a major limitation of current ExPEC antibiotic therapy. New antibacterials that can circumvent resistance problem such as antimicrobial peptides (AMPs) are critically needed. Here, we evaluated the efficacy of Lactobacillus rhamnosus GG (LGG) derived peptides against APEC and uncovered their potential antibacterial targets. Three peptides (NPSRQERR: P1; PDENK: P2, and VHTAPK: P3) displayed inhibitory activity against APEC. These peptides were effective against APEC in biofilm and chicken macrophage HD11 cells. Treatment with these peptides reduced the cecum colonization (0.5 to 1.3 logs) of APEC in chickens. Microbiota analysis revealed two peptides (P1 and P2) decreased Enterobacteriaceae abundance with minimal impact on overall cecal microbiota of chickens. Bacterial cytological profiling showed peptides disrupt APEC membrane either by causing membrane shedding, rupturing or flaccidity. Further, gene expression analysis revealed that peptides downregulated the expression of omp C (>13.0 folds), omp F (>11.3 folds) and mla A (>4.9 folds) genes responsible for maintenance of outer membrane (OM) lipid asymmetry. Consistently, immunoblot analysis also showed decreased levels of OmpC and MlaA proteins in APEC treated with peptides. Alanine scanning studies revealed residues crucial (P1: N, E, R and P; P2: D and E; P3: T, P, and K) for their activity. Overall, our study identified peptides with new antibacterial target that can be developed to control APEC infections in chickens, thereby curtailing poultry-originated human ExPEC infections. Importance APEC is a subgroup of ExPEC and considered as a foodborne zoonotic pathogen transmitted through consumption of contaminated poultry products. APEC shares genetic similarities with human ExPECs, including uropathogenic E. coli (UPEC) and neonatal meningitis E. coli (NMEC). Our study identified LGG-derived peptides (P1: NPSRQERR, P2: PDENK, and P3: VHTAPK) effective in reducing APEC infection in chickens. Antimicrobial peptides (AMPs) are regarded as ideal candidates for antibacterial development because of their low propensity for resistance development and ability to kill resistant bacteria. Mechanistic studies showed peptides disrupt APEC membrane by affecting MlaA-OmpC/F system responsible for maintenance of OM lipid asymmetry, a promising new druggable target to overcome resistance problem in Gram-negative bacteria. Altogether, these peptides can provide a valuable approach for development of novel anti-ExPEC therapies, including APEC, human ExPECs and other related Gram-negative pathogens. Further, effective control of APEC infections in chickens can curb poultry-originated ExPEC infections in humans.

Modeling and Exact Reliability for a Consecutive Linear (k1,k2,…,kn−r+1)-Out-of-r-from-n: F System and Consecutive Circular (k1,k2,…,kn)-Out-of-r-from-n: F System

The consecutive linear [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text]:F system consists of [Formula: see text] linear ordered components and the consecutive circular [Formula: see text]-out-of-[Formula: see text]-from-[Formula: see text]:F system consists of [Formula: see text] circular ordered components. In this paper, we suggest, for the first time, modeling and exact reliability for these models. The linear system fails if and only if there exists a [Formula: see text]-order statistic of [Formula: see text]-consecutive [Formula: see text] [Formula: see text] of components in the failed state, [Formula: see text], [Formula: see text]; and the circular system fails if and only if there exists a [Formula: see text]-order statistic of [Formula: see text]-consecutive [Formula: see text] [Formula: see text] of components in the failed state, [Formula: see text], [Formula: see text]. In this paper, we designed an innovative algorithm to obtain the exact reliability for an extensive class of consecutive linear and circular systems. In continuation, there are the MATLAB Programs of exact reliability for consecutive linear and circular systems. In the following, we applied comparative and numerical results and calculated the exact reliability of this strategic systems. Finally, we calculated the exact reliability for two real-world practical examples.

An evaluation of an electronic audit and feedback system for patient safety in a tertiary hospital setting: A study protocol

An electronic audit and feedback (e-A&F) system was developed to support healthcare providers’ awareness of their own performance, improve delivery of care and ultimately the safety of patients while in hospital. The point-of-care e-A&F system provides healthcare providers, from a 600-bed tertiary hospital in Western Australia, with near real-time feedback via web-based dashboards. The aim of this evaluation is to determine the implications of e-A&F across multiple dimensions and domains of care in a tertiary hospital setting. The study also aims to address the paucity in the literature by validating hypothesised design and implementation mechanisms on its effectiveness. Key datasets to be examined include those related to patient outcomes, staff behaviour and costs. Quantitative methods, such as interrupted time series analysis and multiple logistic regression analysis, amongst other methods, will be employed to achieve these aims.