Estimation of the finite population mean using extreme values and ranks of the auxiliary variable in two-phase sampling

This study aimed to improve the estimation of the mean of the dependent variable by incorporating the smallest and largest values and ranks of the independent variable. To achieve this, we introduce two new classes of estimators that offer enhanced accuracy compared with the existing approaches, as evaluated using the mean squared error (MSE) criterion. The key features of the proposed estimators are examined through a first-order approximation method, particularly focusing on the bias and mean squared error under two-phase sampling. In addition, their performance is assessed using simulated populations generated from six different distributions with varying parameter settings, along with three real datasets. Furthermore, the findings show that the new estimators achieve lower mean squared errors compared with existing methods

Governors and directors: Competing models of corporate governance

Why do we use the term ‘corporate governance’ rather than ‘corporate direction’? Early British joint stock companies were normally managed by a single ‘governor’. The ‘court of governors’ or ‘board of directors’ emerged slowly as the ruling body for companies. By the nineteenth century, however, companies were typically run by directors while not-for-profit entities such as hospitals, schools and charitable bodies had governors. The nineteenth century saw steady refinement of the roles of company directors, often in response to corporate scandals, with a gradual change from the notion of the director as a ‘representative shareholder’ to the directors being seen collectively as ‘representatives of the shareholders’. Governors in not-for-profit entities, however, were regarded as having broader responsibilities. The term ‘governance’ itself suggests that corporate boards should be studied as ‘political’ entities rather than merely through economic lenses such as agency theory

The influence of green trade openness, natural resources rent, institutional quality, and R&D investment on environmental sustainability in the OECD: testing the EKC and LCC hypotheses

IntroductionThis study examines the impact of green trade openness, natural resource rents, institutional quality, and R&D investment on environmental sustainability across OECD countries from 2007 to 2022, testing both the Environmental Kuznets Curve (EKC) and Load Capacity Curve (LCC) hypotheses.MethodsWe apply panel econometric techniques, including CS-ARDL and nonlinear NARDL models, alongside causality analysis, to assess bidirectional and asymmetric relationships among variables.ResultsGreen trade openness, institutional quality, and R&D investment significantly reduce CO2 emissions and enhance load capacity. Conversely, natural resource rents increase emissions and degrade sustainability metrics. The EKC hypothesis holds with an inverted-U shape, while the LCC demonstrates sustainability improvement beyond economic thresholds.DiscussionFindings stress the critical role of governance, innovation, and sustainable trade in ecological outcomes. Policy recommendations advocate reinvestment of resource rents into green innovation and strengthening of institutional frameworks to align economic and environmental goals

Fertility awareness and oocyte cryopreservation among obstetrics and gynecology physicians

Background: Fertility awareness, including the natural decline in fertility with age and fertility preservation through oocyte cryopreservation, is vital for reproductive health. OB/GYN physicians play a crucial role in educating women on these topics, yet their knowledge and attitudes in Saudi Arabia are underexplored. This study assessed OB/GYN physicians’ perceptions, knowledge, and attitudes regarding fertility awareness and oocyte cryopreservation, focusing on their understanding of age-related fertility decline and integration into patient discussions. Methods: A cross-sectional survey of 100 OB/GYN physicians in Saudi Arabia was conducted from April to July 2024, using stratified random sampling. The survey evaluated their knowledge of fertility issues, attitudes towards preconception planning, and views on incorporating oocyte cryopreservation discussions in practice. Data were analyzed using descriptive statistics and ANOVA. Results: Most physicians showed substantial knowledge of fertility decline, with 71% recognizing a slight decline at 35-39 years and 57% a marked decline at 45-49 years. Nearly all (96%) supported OB/GYN-initiated discussions on preconception planning, and 95% endorsed discussing age-related fertility decline. Additionally, 78% favoured discussing oocyte cryopreservation, with 63% supporting its inclusion in routine visits. Concerns about discussion frequency and potential emotional distress were noted by a minority. Conclusions: OB/GYN physicians in Saudi Arabia are generally aware of fertility issues, but knowledge gaps persist, particularly among less experienced physicians. While there is broad support for proactive fertility discussions, some reservations remain, highlighting the need for targeted educational initiatives

Feasibility and acceptability of a tailored health coaching intervention to improve type 2 diabetes self-management in Saudi Arabia: a mixed-methods randomised feasibility trial

Background Around one-third of the population of Saudi Arabia have been diagnosed with type 2 diabetes, a condition often requiring lifestyle changes. Personalised health coaching, a strategy developed to assist individuals in overcoming challenges to adopt healthy behaviours, has not yet been widely applied in the country. Aims We aim to explore the feasibility and acceptability of tailored health coaching in Saudi Arabia, in order to help those with type 2 diabetes to more effectively manage their condition. Methods Using a mixed-methods approach, this research involved a randomised controlled trial with 30 Saudi adults who have type 2 diabetes. They were randomly allocated into either the intervention or control arm for 12 weeks. The Capability, Opportunity, Motivation and Behaviour framework was used to guide the intervention implementation along with the Behaviour Change Techniques Taxonomy V.1. The primary goal was to assess the suitability and duration of the intervention, recruitment, retention and completion rates. The secondary outcome focused on the preliminary efficacy of the health coaching measured by the glycaemic index, blood pressure, body mass index (BMI), waist circumference, weight, patient self-efficacy and diabetes self-management. Results The results showed high rates of eligibility, recruitment and retention (a screening rate of 90%, a recruiting rate of 79% and a retention rate of 97%). Notable improvements were observed in the health coaching group across five outcomes: haemoglobin A1c, BMI, waist circumference, patient self-efficacy and diabetes self-care. Qualitative findings highlighted the participants’ perceived benefits from the intervention, including enhanced motivation, better understanding of diabetes management and a supportive coaching relationship. Participants expressed high satisfaction with the intervention and advocated for its expansion. Conclusion The findings demonstrated positive outcomes, supporting the need for a larger randomised controlled trial to evaluate the efficacy of health coaching in improving diabetes self-management among individuals with type 2 diabetes in Saudi Arabia

Local linear estimation for the censored functional regression

This work considers the Local Linear Estimation (LLE) of the conditional functional mean. This regression model is used when the independent variable is functional, and the dependent one is a censored scalar variable. Under standard postulates, we establish the asymptotic distribution of the LLE by proving its asymptotic normality. The obtained results show the superiority of the LLE approach over the functional local constant one. The feasibility of the studied model is demonstrated using artificial data. Finally, the usefulness of the obtained asymptotic distribution in incomplete functional data is highlighted through a real data application

Facial Lichen Planus Pigmentosus-Like Pigmentation Induced by Vicks VapoRub: A Case Report

Khalid M Al-Husain,1 Musaed M Alsebayel,2 Sarah Al-Breiki,1 Nasser Almulhim,3 Ahmed Alsayyah4 1Department of Dermatology, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia; 2Department of Dermatology, King Fahad University Hospital, Al-Khobar, Saudi Arabia; 3College of Medicine, King Faisal University, Al-Ahsa, Saudi Arabia; 4Department of Pathology, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi ArabiaCorrespondence: Nasser Almulhim, King Faisal University, 36362, Al Mazrooa, Al-Ahsa, Eastern Province, Saudi Arabia, Tel +966536537773, Email [email protected]: Lichen planus pigmentosus is a variant of lichen planus characterized by gray-brown hyperpigmented macules and patches occurring in sun exposed areas. Vicks VapoRub is an inhalant ointment frequently used to relieve symptoms of upper respiratory tract infections. We report a case of lichen planus pigmentosus induced by Vicks VapoRub and successfully treated with topical tacrolimus 0.1% cream.Keywords: lichen planus pigmentosus, Vicks VapoRub, tacrolimus, facial hyperpigmentation, lichen planu

Prevalence and Pattern of Cerebral Variations during Endovascular Diagnostic Angiography in Saudi Patients: A Retrospective Observational Study

Background:  Previous studies detected large number of variations in circle of Willis in normal populations. There is limited data for the effect and correlation of normal varieties and pathologic vascular anomalies Purpose:  Prevalence of normal variants and impact of its presence in decision making process. Patients and methods: Ninety patients\u27 records underwent therapeutic angiography were retrospectively reviewed and reallocated into two equal groups according to pathology (group 1=vascular malformation group, group 2= ischemic insults). Age, sex, type of pathology, site of normal variants and finally their impact on decision making process were calculated.    Results: The mean and standard deviation of age in our study was found to be (40.18 years ± 15.6), most of patients were between 30-40 years old. The total number of normal variants that were detected in our study either at extra- or intracranial vascular tree was 46 variants. Forty-nine cases were "ignored" or added no impact on the proposed plan during neurointervention. The sensitivity of normal variants in changing decision making process was seen in 15% of cases while the specificity was 100%. Conclusion:  Normal variants were detected accidently through DSA for therapeutic purposes in 47% of cases. The term normal vascular variation is simple to be defined per se. However, when additional vascular event (aneurysm or AVM) was detected, the neurointerventionist should be aware of its presence, possible complications and how to proceed to the target without additional damage. These variations should be reported and explained to the patient and/or family especially when they interfere with operative plan or decision to avoid medicolegal consequences

Weekly Semaglutide Use Shows Promise Among Type 2 Diabetes Patients at a Polyclinic in Alahsa, Saudi Arabia: A Retrospective Study

Background: Glucagon-like peptide-1 receptor agonist (GLP-1RAs) are vital for glycemic control and weight loss. Due to lack of extensive evidence on semaglutide efficacy in Saudi population, this study aimed to evaluate the effectiveness of once-weekly (OW) semaglutide in adults with type 2 diabetes.Methods: This retrospective cohort study conducted in king faisal university polyclinic in 2023 which assessed patients with type 2 diabetes who started treatment with OW semaglutide alone or combined with other antidiabetic medications. Measurements taken before and six months after starting OW semaglutide which include glycated hemoglobin (HbA1c), body weight and other health variables.Results: A total of 22 participants were enrolled in the study. After the intervention the HgA1c and body weight were significantly decreased (p < 0.001, P < 0.001) respectively. Additionally, there were notable decrease with statistical level in serum cholesterol, triglycerides (TG), low density lipoprotein (LDL) and alanine transferase (ALT) (P = 0.001, p = 0.001, p = 0.013, p < 0.001) whereas high density lipoprotein (HDL) and creatinine level did not show statistical difference (p = 0.057, p = 0.829). Conclusion: This study examined the impact of OW semaglutide on individuals with type 2 diabetes, assessing HgA1c, body weight and other health metrics. Results showed significant health improvements post-intervention, suggesting key areas for further research. Future studies could explore OW semaglutide long-term effects on type 2 diabetes in the Saudi population

Charting sustainable urban development through a systematic review of SDG11 research

The Sustainable Development Goal (SDG) 11 underscores the imperative of creating inclusive, safe, resilient and sustainable cities and communities by 2030. Here we employ bibliometric techniques to assess the evolving landscape of SDG11 research. Using a comprehensive dataset of over 21,000 scholarly publications, we investigate publication trends, thematic focus areas, authorship patterns, keyword co-occurrences and citation networks related to SDG11 research. The results reveal a consistent increase in research output, reflecting the growing global interest in urban sustainability studies. We identify influential authors, organizations and countries shaping the research landscape, highlighting existing global collaborative networks and emerging research hubs. Core thematic areas emphasize critical topics and interdisciplinary connections. Citation networks underscore the impacts of disseminating research outputs, including seminal works. This study offers insights for policymakers, academics and practitioners to align their collective efforts toward sustainable, inclusive and climate-resilient urban development. Moreover, it advances SDG11 by noting opportunities for further research, knowledge dissemination and international collaboration