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Abstract Partial accelerated life tests (PALTs) are employed when the results of accelerated life testing cannot be extended to usage circumstances. This work discusses the challenge of different estimating strategies in constant PALT with complete data. The lifetime distribution of the test item is assumed to follow the power half-logistic distribution. Several classical and Bayesian estimation techniques are presented to estimate the distribution parameters and the acceleration factor of the power half-logistic distribution. These techniques include Anderson–Darling, maximum likelihood, Cramér von-Mises, ordinary least squares, weighted least squares, maximum product of spacing and Bayesian. Additionally, the Bayesian credible intervals and approximate confidence intervals are constructed. A simulation study is provided to compare the outcomes of various estimation methods that have been provided based on mean squared error, absolute average bias, length of intervals, and coverage probabilities. This study shows that the maximum product of spacing estimation is the most effective strategy among the options in most circumstances when adopting the minimum values for MSE and average bias. In the majority of situations, Bayesian method outperforms other methods when taking into account both MSE and average bias values. When comparing approximation confidence intervals to Bayesian credible intervals, the latter have a higher coverage probability and smaller average length. Two authentic data sets are examined for illustrative purposes. Examining the two real data sets shows that the value methods are workable and applicable to certain engineering-related problems.

The unit new X-Lindley distribution, which is a novel one-parameter distribution on the unit interval, is presented in this study. It was developed by altering the new X-Lindley distribution using the exponential transformation. This new one-parameter distribution's fundamental features, including moments, incomplete moments, Lorenz and Bonferroni curves, Gini index, mode, extropy, Havrda and Charvat entropy, Rényi entropy, and Tsallis entropy, are explored. Additionally, it has bathtub-shaped hazard rate functions and monotonically increasing hazard rate functions with a single parameter. The new distribution is therefore sufficiently rich to model real data. Also, different estimation methods, such as maximum likelihood, least-squares, and weighted least-squares, are used to estimate the parameters of this model, and using a simulation research, their respective performances are evaluated. Finally, two real-life datasets are used to demonstrate the suggested model's competency.

Ahmed Ali Amer,1,&ast; Esam Ahmed Ghanem Abu El Wafa Ali,2,&ast; Esam Sayed Ahmed,2,&ast; Mohamed Ateto Hamed,2,&ast; Wael el Shazly Eata,3,&ast; Ibrahim Amer1,&ast; 1Ophthalmology Department, Qena Faculty of Medicine, South Valley University, Qena, Egypt; 2Ophthalmology Department, Al Azhar University, Assuit, Egypt; 3Ophthalmology Department, Luxor University, Luxor, Egypt&ast;These authors contributed equally to this workCorrespondence: Ahmed Ali Amer, Tel +20 101 182 7000, Email AhmedALi.ophth@gmail.comPurpose: This study aimed to compare the short-term outcome of implanting the Visian implantable collamer lens V4 ICL versus the Visian V4c ICL in patients with moderate and high myopia.Patients and Methods: This is a retrospective that was conducted on patients with moderate or high myopia who were scheduled for ICL implantation at our institution, Patients who underwent V4 ICL implantation with peripheral iridectomy were assigned to group A, and those who underwent V4c ICL implantation without peripheral iridectomy were assigned to group B. In group A, a preoperative peripheral iridectomy was performed. In group B, the patients received cycloplegic and dilating agents. The patients underwent a complete ocular examination preoperatively and during the follow-up visits that were conducted at 3, 6, and 12 months postoperatively.Results: This study included 214 eyes from 107 patients; group A included 110 eyes, and group B included 104 eyes. Postoperatively, the UCVA and BCVA showed statistically significant improvement across the follow-up time points (p< 0.001), with no significant difference between the two groups. No statistically significant difference was found between the two groups in the mean achieved correction or the residual refraction. Both groups showed a strong correlation between the target and the achieved correction, with R2 = 0.99 in the two groups. No significant difference was found between the two groups in the IOP across all time measures. However, the intraocular pressure showed a statistically significant postoperative increase in group A (p=0.004), and no significant change in group B (p=0.817). There was a downward slope in the vaults of both groups across time, with significant variation in the last follow-up measure compared to the 3-month measure in the two groups (p< 0.001). No significant difference was found between the two groups across all time measures.Conclusion: The current study adds new evidence concerning the feasibility, safety, and efficacy of ICL V4c implantation for the treatment of moderate and high myopia, with safer postoperative IOP.Keywords: moderate and high myopia, Visian implantable collamer lens, central hole, peripheral iridectomy

This paper offers the odd inverted Topp–Leone family of probability distributions with new statistical models capable of fitting data in various fields. Different density function shapes as well as different shapes of hazard rate are observed. Explicit formulas of structural properties to the family are discussed. The two-parameter inverted Topp-Leone exponential distribution, which has been created as part of the offered family, has been explored due to its intended features for the statistical modeling. Parameter estimation of the inverted Topp–Leone exponential distribution is considered under complete and censored samples. The usefulness of the estimators is regarded by employing Monte Carlo simulations. We deal with practical data analysis for new modeling strategy, which gives quite convenient results compared with some other models.

Recently, the two-parameter Xgamma distribution (TPXGD) is suggested as a new lifetime distribution for modeling some real data. The TPXGD is investigated in different areas and generalized to other forms by many of the researchers. The acceptance sampling plans are one of the main important statistical tools in production and engineering fields. In this paper, modified acceptance sampling plans for the TPXGD are proposed with the assumption that the lifetime is truncated at a predetermined level. The mean of the TPXGD model is utilized as a quality parameter. The variables of the acceptance sampling plans including the acceptance numbers, the minimum sample sizes, operating characteristic function and the producer's risk are investigated for various values of the model parameters. Numerical examples are offered to illustrate the process of the proposed plans. Also, a real data is fitted to the TPXGD and an application based on the suggested acceptance sampling plans is considered for explanation.

Ibrahim Amer,1 Abdelhakeem Elaskary,1 Ali Mostafa,2 Hazem A Hazem,2 Ahmed Omar,2,3 Ahmed Abdou2 1Ophthalmology Department, Faculty of Medicine, AL-Azhar University, Assiut, Egypt; 2Ophthalmology Department, Faculty of Medicine, Assiut University, Assiut, Egypt; 3University Hospitals Eye Institute and the Department of Ophthalmology and Visual Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio, USACorrespondence: Ahmed AbdouOphthalmology Department, Faculty of Medicine, Assiut University, Assiut 71515, EgyptTel +201004343388Email Abdou.ahmed@aun.edu.egPurpose: To compare the visual, refractive and topographic outcomes of standard and accelerated corneal collagen cross-linking (CXL) in pediatric keratoconus patients.Methods: Prospective, comparative observational study on 68 eyes of 35 pediatric keratoconus patients (< 18 years). Patients were classified into two groups, group (I) included 34 eyes and received standard “Epi-Off” CXL (3 mW/cm2, 30 min.) and group (II) included 34 eyes and received accelerated “Epi-Off” CXL (9 mW/cm2, 10 min.). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), spherical equivalent (SE), simulated keratometry (Sim K-1, Sim K-2, K-max, K-mean), cylindrical (CYL), pachymetry and Q-value were evaluated preoperatively and for 3 years postoperatively.Results: Postoperative UDVA and CDVA did not significantly change in both groups after 3 years. Postoperative SE was increased significantly in accelerated CXL (p=0.012) with no significant change in the postoperative cylinder in both procedures. Standard CXL had greater “significant” effect in decreasing Sim K-1, K-max and K-mean. The mean reduction in postoperative corneal pachymetry (at thinnest location) was significant in standard CXL (18.4 μm) (p=0.001). No significant change was noticed in postoperative Q-value.Conclusion: Standard and accelerated CXL protocols are efficient in pediatric keratoconus management with better outcomes in the standard procedure.Keywords: standard CXL, accelerated CXL, corneal collagen cross-linking, pediatric keratoconus

The method of maximum likelihood estimation based on ranked set sampling (RSS) and some of its modifications is used to estimate the unknown parameters of the new Weibull-Pareto distribution. The estimators are compared with the conventional estimators based on simple random sampling (SRS). The biases, mean squared errors, and confidence intervals are used to the comparison. The effect of the set size and number of cycles of the RSS schemes are addressed. Monte Carlo simulation is carried out by using R. The results showed that the RSS estimators are more efficient than their competitors using SRS.

Monkeypox is a rare disease but is increasing in incidence in different countries since the first case was diagnosed in the UK by the United Kingdom (UK) Health Security Agency on 6 May 2022. As of 9 August, almost 32,000 cases have been identified in 89 countries. In endemic areas, the monkeypox virus (MPXV) is commonly transmitted through zoonosis, while in non-endemic regions, it is spread through human-to-human transmission. Symptoms can include flu-like symptoms, rash, or sores on the hands, feet, genitalia, or anus. In addition, people who did not take the smallpox vaccine were more likely to be infected than others. The exact pathogenesis and mechanisms are still unclear; however, most identified cases are reported in men who have sex with other men (MSM). According to the CDC, transmission can happen with any sexual or non-sexual contact with the infected person. However, a recent pooled meta-analysis reported that sexual contact is involved in more than 91% of cases. Moreover, it is the first time that semen analysis for many patients has shown positive monkeypox virus DNA. Therefore, in this review, we will describe transmission methods for MPXV while focusing mainly on potential sexual transmission and associated sexually transmitted infections. We will also highlight the preventive measures that can limit the spread of the diseases in this regard.

This paper studies estimation of the parameters of the generalized Gompertz distribution based on ranked-set sample (RSS). Maximum likelihood (ML) and Bayesian approaches are considered. Approximate confidence intervals for the unknown parameters are constructed using both the normal approximation to the asymptotic distribution of the ML estimators and bootstrapping methods. Bayes estimates and credible intervals of the unknown parameters are obtained using differential evolution Markov chain Monte Carlo and Lindley’s methods. The proposed methods are compared via Monte Carlo simulations studies and an example employing real data. The performance of both ML and Bayes estimates is improved under RSS compared with simple random sample (SRS) regardless of the sample size. Bayes estimates outperform the ML estimates for small samples, while it is the other way around for moderate and large samples.

In this paper we introduce new class of open sets called weak N-open sets and we study the relation between N-open sets , weak N-open sets and some other open sets. We prove several results about them.

Increased carotid intima-media thickness (cIMT) is associated with heart failure (HF) in previous studies, but it is not known whether the association of cIMT differs between HF with reduced (HFrEF) versus preserved ejection fraction (HFpEF). We studied 6699 participants (mean age 62 ± 10 years, 47% male, and 38% white) from the Multi-Ethnic Study of Atherosclerosis (MESA) with baseline cIMT measurements. We classified HF events as HFrEF (EF

BackgroundSouth Asians are the second fastest growing ethnic group in the United States, and they have a high risk for cardiovascular disease (CVD). Moderate alcohol consumption has been associated with lower CVD risk in some race/ethnic groups, but the association of alcohol consumption and atherosclerosis in South Asians has not been investigated.Methods and resultsWe used data from 906 South Asian participants who participated in the Mediators of Atherosclerosis in South Asians Living in America (MASALA) cohort (2010-2012). Alcohol consumption was ascertained via questionnaire, coronary artery calcium (CAC) was measured with computed tomography, and common carotid artery intima-media thickness (cIMT) was measured using B-mode ultrasonography. We used multivariable regression models to examine cross-sectional associations of alcohol consumption with the presence and amount of CAC and cIMT. Compared with never drinkers, participants consuming 4-7 drinks/week had a 63% decreased odds of any CAC after adjusting for potential confounders and mediators. Participants consuming 4-7 drinks/week had significantly lower odds of CAC score between 1 and 300 [OR (95% CI): 0.34 (0.16-0.72)]. A similar inverse association was seen for the odds of CAC>300 [OR (95% CI): 0.28 (0.07-0.97)]. Alcohol consumption of >7 drinks/week was associated with a 0.096 mm increase in common-cIMT.ConclusionThere was an inverse association between the amount of alcohol intake and CAC among South Asians while a positive association was found between alcohol consumption and common-cIMT. Long-term follow-up of the MASALA cohort will examine prospective associations of alcohol intake with the progression of subclinical atherosclerosis, incident CVD events, and mortality.

The unit new X-Lindley distribution, which is a novel one-parameter distribution on the unit interval, is presented in this study. It was developed by altering the new X-Lindley distribution using the exponential transformation. This new one-parameter distribution’s fundamental features, including moments, incomplete moments, Lorenz and Bonferroni curves, Gini index, mode, extropy, Havrda and Charvat entropy, Renyi entropy, and Tsallis entropy, are explored. Additionally, it has ´ bathtub-shaped hazard rate functions and monotonically increasing hazard rate functions with a single parameter. The new distribution is therefore sufficiently rich to model real data. Also, different estimation methods, such as maximum likelihood, least-squares, and weighted least-squares, are used to estimate the parameters of this model, and using a simulation research, their respective performances are evaluated. Finally, two real-life datasets are used to demonstrate the suggested model’s competency. [ABSTRACT FROM AUTHOR]

Arterial calcification reflects an atherosclerotic process associated with vascular stiffness. Whether baseline coronary artery calcium (CAC) and extra-coronary calcium (ECC), measured using noncontrast computed tomography imaging, are associated with incident hypertension is poorly understood. We studied participants from the Multi-Ethnic Study of Atherosclerosis without measured or self-reported hypertension at baseline. Incident hypertension was defined by blood pressure criteria (BP, ≥140/90 mmHg), BP medication use, or both, and was assessed at in-person visits. We analyzed incident hypertension using multivariable-adjusted discrete-time proportional hazards models. Net reclassification improvement (NRI) assessed whether CAC reclassified hypertension risk when added to the Framingham hypertension risk score. Among 3,304 subjects analyzed, mean age was 59 ± 10 years; 48% were male and 42% were white. There were 1,283 incident hypertension cases over a median (interquartile range) follow-up time of 10.6 (4.5, 11.5) years. Each 1-unit increase in ln(CAC+1) was independently associated with a 12% higher risk of hypertension (95% confidence interval [CI] 9% to 16%). Relative to CAC = 0, patients with CAC >400 had a hazard ratio for incident hypertension of 2.2 (95% CI 1.8 to 2.9). There was no interaction by age, gender, or baseline BP (p = 0.43, 0.19, 0.09, respectively). Continuous NRI analyses demonstrated that CAC can reclassify risk of incident hypertension; NRI = 0.19 (95% CI 0.10 to 0.26). Furthermore, all measurements of ECC were significantly associated with incident hypertension, even after adjustment for CAC (hazard ratios ranging from 1.36 to 1.38). In conclusion, patients with CAC and ECC are at markedly higher risk of incident hypertension and may benefit from more intensified prevention efforts.

Background: Spodoptera littoralis is an important agricultural pest; thus, knowledge about the effect of latex serum and latex-synthesized nanoparticles of Calotropis procera on this species can assist in its management.. Nanotechnology is currently taking root in the agriculture economy as a substitute for pest management that is targeted, safe, and effective. The repellent and antifeedant efficacy of C. procera latex serum and its nanoparticles against S. littoralis fourth instar larvae was investigated in this work. Methods: The process of synthesizing silver nanoparticles has been carried out, followed by their subsequent characterization. The objective of this study was to assess the antifeedant properties of the latex serum and its nanoparticles against the 4th instar larvae of S. littoralis through the implementation of a bioassay. Results: With rising latex serum content, the proportion of repellency and hunger rose. In comparison to insects injected with latex serum, utilizing nanoparticles of LAgNPs with this larva via injection resulted in much increased mortality. Conclusion: According to the findings of this study, insects injected with LAgNPs died at a substantially higher rate than insects injected with latex serum. LAgNPs was efficient against S. littoralis larvae and can thus be utilized to specifically control the pest. [ABSTRACT FROM AUTHOR]

In this article, we address the problem of estimating the parameters of Farlie-Gumbel-Morgenstern bivariate Weibull distribution using ranked set sample (RSS) design. The suggested estimators of the FGMBW distribution parameters are compared with their counterparts based on simple random sampling (SRS) via Monte Carlo simulations studies. An example of a real data set consists of times (in days) to the first and second recurrence of infection for 30 kidney patients is considered for illustration. It turns out that the RSS estimators results in an improvement in efficiency as compared to the simple random sampling estimators based on the same number of measured units for all cases considered in this study. [ABSTRACT FROM AUTHOR]

Missing data occurs frequently in sample surveys. Numerous imputation techniques have been proposed to tackle the problem of missing data, and, in fact, limited works are available in the literature to deal with the issue of missingness while the data are ridden with measurement errors (ME). In addition, no work has been done on the robustness to handle the issue of missing data when it is contaminated with correlated measurement errors (CME). This article proposes some robust imputation methods (RIM) to impute the missing data in the presence of CME. The mean square error (MSE) of the proposed RIM is derived from the first-order approximation and examined with the MSE of the conventional imputation methods. The results are theoretically established and explained using a vast simulation study. Two applications of real data sets are presented to illustrate the efficiency and superiority of the suggested estimators relative to some estimators considered in this study.

Abstract The nuclear receptor-related factor 1 (Nurr1), an orphan nuclear receptor in microglia, has been recognized as a major player in attenuating the transcription of the pro-inflammatory genes to maintain CNS homeostasis. In this study, we investigate Nurr1 trans-repression activity by targeting this receptor with one of the indole derivatives 3-Indole acetic acid hydrazide (IAAH) loaded onto zinc iron oxide (ZnFe2O4) NPs coated with PEG. XRD, SEM, FTIR, UV–Vis spectroscopy, and DLS were used to characterize the synthesized IAAH-NPs. The anti-inflammatory properties of IAAH-NPs on LPS-stimulated SimA9 microglia were assayed by measuring pro-inflammatory cytokine gene expressions and protein levels using RT-PCR and ELISA, respectively. As a result, IAAH-NPs showed an ability to suppress pro-inflammatory genes, including IL-6, IL-1β, and TNF-α in LPS-stimulated SimA9 via targeting Nurr1. The current study suggests that ZnFe2O4 NPs as a delivery system can increase the efficiency of cellular uptake and enhance the IAAH ability to inhibit the pro-inflammatory cytokines. Collectively, we demonstrate that IAAH-NPs is a potential modulator of Nurr1 that combines nanotechnology as a delivery system to suppress neuroinflammation in CNS which opens a window for possible ambitious neuroprotective therapeutic approaches to neuro disorders.

Recently, MiniMax ranked set sampling (MiniMax RSS) scheme is suggested for population mean estimation. In this article, we consider moving extreme ranked set sampling (MERSS) and MiniMax RSS for estimating the distribution function of a random variable. Using the maximum likelihood estimation method, new estimators of the cumulative distribution function (CDF) are derived and also their variances are obtained. In the light of a simulation study, we conclude that the estimators based on MiniMax RSS work well compared to those based on MERSS setups regardless of the ranking quality. Additionally, the proposed concomitant-based CDF estimators tend to be superior to their analogs as long as the ranking process is done with fairly good accuracy. For the sake of illustration, two empirical datasets are considered to show the applicability of the proposed estimators in practice. [ABSTRACT FROM AUTHOR]

The ranked set sampling (RSS) procedure was initially established by McIntyre (1952) for estimating the mean of forage and pasture yield as more precise than simple random sampling (SRS). Recently, Aldrabseh and Ismail (2023) suggested the except extreme RSS (EERSS) approach as a modification to RSS for estimating the population mean. In this paper, a new estimator of the population variance is proposed using the EERSS method. The mean squared error and bias equations of the new estimator are derived. When the underlying distribution is non-symmetric, a simulation study is conducted to evaluate the suggested estimator relative to SRS and RSS, based on the same number of measured units, in terms of the relative precision and bias values for several sample sizes. For symmetric distributions, the exact values of the bias and relative precision of the EERSS variance estimator are evaluated. Two real datasets are utilized to illustrate the performance of the suggested variance estimator. It is found that the EERSS variance estimator is more efficient than the SRS estimator and more precise than RSS in most cases, especially for small set sizes.

To define useful numbers having values from 0 to 1, as percentages, probabilities, and proportions, the unit probability models are often employed in probability and statistics. In this paper, a new two-parameter model on the unit interval, entitled the unit Mirra distribution (UMD) is suggested which is a modification of the Mirra distribution (MD). Various statistical properties of the proposed UMD as the rth moment, variance, inverse moments, and incomplete moments are presented. Also, the distributions of order statistics, coefficients of variation and skewness, stochastics ordering, and median and mean deviations are provided. The reliability functions such the hazard function, survival function, odds function, reversed hazard rate function, and the mean residual function are provided with supported graphical representation. The Lorenz curve, Gini index, and Bonferroni curve of the UMD with some simulations are included. The distribution parameters are estimated based on the maximum likelihood estimation, ordinary least squares estimation, Anderson-Darling and maximum product of spacing’s estimation. Finally, two different applications of actual data sets that represent the times to infection of kidney dialysis patients in months and the trade share data on unit interval are carried out to evaluate the model's performance as compared to some competitors. It turns out that the suggested UMD can serve as a good alternative for modeling these data sets.

Building efficient sampling procedures to provide more accurate results with small sample sizes is one of the main goals in sampling surveys. The ranked set sampling (RSS) is a well-known procedure for selecting representative samples and improving parametric estimation by employing ranking on observations. In order to have a more efficient sampling procedure, new sampling procedures are proposed and investigated in this article. The main focus of this article is to enhance the mean estimation of the study population using the proposed RSS procedures. The performance of the proposed sampling procedures is compared with their competitors in RSS, double RSS (DRSS), extreme RSS (ERSS), and double extreme RSS (DERSS) by conducting simulation studies for numerous (symmetric and asymmetric) distributions. An application to a real dataset is also considered to exemplify the achievement of the proposals. Numerical simulations show that the new modified estimators are unbiased for the population mean for symmetric distributions and they outperform their competitors in most of the cases investigated in this article. [ABSTRACT FROM AUTHOR]

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