New extensions of Rayleigh distribution based on inverted-Weibull and Weibull distributions

The Rayleigh distribution was proposed in the fields of acoustics and optics by lord Rayleigh. It has wide applications in communication theory, such as description of instantaneous peak power of received radio signals, i.e. study of vibrations and waves. It has also been used for modeling of wave propagation, radiation, synthetic aperture radar images, and lifetime data in engineering and clinical studies. This work proposes two new extensions of the Rayleigh distribution, namely the Rayleigh inverted-Weibull (RIW) and the Rayleigh Weibull (RW) distributions. Several fundamental properties are derived in this study, these include reliability and hazard functions, moments, quantile function, random number generation, skewness, and kurtosis. The maximum likelihood estimators for the model parameters of the two proposed models are also derived along with the asymptotic confidence intervals. Two real data sets in communication systems and clinical trials are analyzed to illustrate the concept of the proposed extensions. The results demonstrated that the proposed extensions showed better fitting than other extensions and competing models

Reliability estimation for the randomly censored pareto distribution

Widespread applications of random censoring in life testing experiments to estimate reliability of engineering products or systems are avialable. Different parametric statistical models such as exponential, Rayleigh, Weibull and Maxwell distributions are used under random censoring scheme. In this paper, random censoring under Pareto distribution is considered. The maximum likelihood estimators (MLE’s) of the model parameters and survival function were derived along with Fisher information matrix and asymptotic confidence intervals. A simulation study was performed to observe the behavior of the MLE’s. The simulation results showed that the bias and MSE were reasonably small in all cases

GC/MS and LC-MS/MS phytochemical evaluation of the essential oil and selected secondary metabolites of Ajuga orientalis from Jordan and its antioxidant activity

The current investigation aimed to shed light in the volatile and non-volatile secondary metabolites of Ajuga orientalis L. from Jordan. GC/MS and GC/FID analysis of the hydrodistilled essential oil obtained from aerial parts of the plant revealed tiglic acid (18.90 %) as main constituent. Each of the methanol and butanol fractions of A. orientalis were screened for their total phenol content (TPC), total flavonoid content (TFC), and antioxidant activity determined by DDPH and ABTS methods. The extracts were then analyzed by LC-ESI-MS/MS to unveil their chemical constituents, especially phenols and flavonoids. Results showed that the AO-B extract had the highest TPC (217.63 ± 2.65 mg gallic acid/g dry extract), TFC (944.41 ± 4.77 mg quercetin /g dry extract), highest DPPH and ABTS antioxidant activity ((4.00 ± 0.20) × 10-2; (3.00 ± 0.20) × 10-2 mg/mL, respectively) as compared to the AO-M extract. LC-ESI-MS/MS analysis of both extracts revealed the presence of several phenolics, flavonoids and nonphenolic acids

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

Bayesian Threshold Moving Average Models

A Bayesian approach in threshold moving average model for time series with two regimes is provided. The posterior distribution of the delay and threshold parameters are used to examine and investigate the intrinsic characteristics of this nonlinear time series model. The proposed approach is applied to both simulated data and a real data set obtained from a chemical system. Key words: Threshold time series, moving average model, Bayesia

Progressive Type-II Censoring Ailamujia distribution Under Binomial Removals with Data Analysis

Ailamujia distribution is a useful lifetime model for several engineering applications. The Ailamujia distribution is a versatile distribution to model the repair time and guarantee the distribution delay time. This study considers the estimation problem for Ailamujia distribution based on progressive Type-II censoring with Binomial removals. The maximum likelihood estimators (MLE’s) for the model parameters were derived along with the asymptotic confidence intervals. A simulation study was performed using different values of sample sizes, parameters, and different number of removed observations to investigate the behavior of the estimators. A real life time data set was analyzed using progressive Type-II Ailamujia distribution and showed appropriate results

Pattern of Uveitis in a Tertiary Hospital in North Jordan and the Impact of Behcet’s Disease

Aim. The purpose of this study is to assess the prevalence of autoimmune-mediated uveitis in relation to other diseases and to describe the clinical patterns of uveitis in a single tertiary hospital in north Jordan. Methods. A cross-sectional retrospective review was performed. We included all patients diagnosed with uveitis in King Abdullah University Hospital (KAUH) ophthalmology clinic and/or patients referred to KAUH rheumatology clinics for evaluation of suspected autoimmune mediated uveitis or for difficult to treat uveitis. This included patients from January 2015 to January 2019. Data collected about patients’ age, sex, anatomical location of the disease, etiology, treatment, complications, and outcomes on vision loss were analyzed. Results. A total of 221 patients were included in our study. The mean (±SD) age was 36 (±16) years. A total of 111 patients were female and 110 were male with a ratio of 1 : 1. Noninfectious uveitis was found to be more common than infectious uveitis (95% vs. 5% respectively). Autoimmune-mediated uveitis accounted for 40% of the total cases. The most common causes of autoimmune-mediated uveitis included Behcet’s disease (n = 41, 19%) and seronegative spondyloarthropathy (n = 29, 13%). The majority of patients (n = 207, 94%) were treated with ophthalmic eye drops, cDMARDs (n = 101, 46%), biologics (n = 33, 15%), and colchicine (n = 30, 14%). Conclusion. Autoimmune-mediated uveitis, most commonly associated with Behcet’s disease and seronegative spondyloarthropathy, represents a high percentage of uveitis in our area. This implies the need for a high index of suspicion at the time of evaluation