Missing data are common in clinical prediction studies, yet their handling may affect not only predictive performance but also which model is judged best. This study examined the stability of classifier selection when missing data handling was changed under controlled, paired evaluation conditions. Using SUPPORT2 data from 9,105 patients, Logistic Regression, Random Forest, and XGBoost were evaluated with median, K nearest neighbor, and iterative imputation. The analysis retained natural missingness, added nested missing completely at random (MCAR) perturbations of 5%, 10%, 20%, and 30%, and included a separate 20% missing at random (MAR) condition. Repeated stratified five fold cross validation used the same patient partitions, model seeds, and artificial missingness masks across corresponding comparisons. Ranking stability was assessed through condition level winner changes, paired rank reversals, and agreement across receiver operating characteristic area under the curve (ROC AUC), Average Precision, and Brier Score. The condition level winner remained stable under natural and mild additional missingness, but became dependent on imputation at higher missingness. Winner changes occurred in 6 of 12 imputation comparisons and 9 of 15 missingness comparisons, while pairwise rank reversals occurred in about 44% of matched repeat comparisons. All three metrics selected the same winner in 8 of 18 conditions. Because competing winners were separated by small ROC AUC margins, the results indicate sensitivity of model selection rather than large performance advantages. Reporting ranking stability alongside conventional performance estimates may therefore provide a more cautious basis for comparative clinical prediction studies.

• Several types of steroids are a class of medications used worldwide to treat pain. Despite significant differences in their use across various age groups, particularly among young people, including university students, steroids offer a significant health benefit when used without a prescription and with guidance from a pharmacist. 425 new Libyan students from various colleges in Gharyan University (Medicine, Pharmacy, Science, Arts, etc.). The data were collected using a structured self-designed questionnaire consisting of 32 items. Descriptive (frequencies and percentages) and inferential statistics (Cronbach's alpha coefficient) were applied to assess internal consistency, and the Chi-squared test and ANOVA. The analysis revealed that 90.4% of students do not use non-steroidal anti-inflammatory drugs for pain, 94.1% do not use them for headaches, and 94.6% do not use them without a prescription. 6.1% reported experiencing stomach pain after use, and 1.6% indicated that they needed a larger dose to achieve the same effect. The Cronbach's alpha coefficient was 0.81, indicating good internal consistency. This study found significant differences in eight question items (29.6%) between genders and in three items between age groups. Thus, students at Gharyan University have a high level of awareness regarding the safe use of non-steroidal anti-inflammatory drugs and avoiding their use without a prescription.

ABSTRACT

The fatigue behavior of 2024 aluminum alloy is strongly influenced by heat treatment conditions, particularly T6 and retrogression and re-ageing (RRA) processes. In this study, specimens obtained from 2024 alloy plates were solution heat-treated at 520°C /2 h and subsequently aged to the T4 condition at 120°C/24 h. All samples were then subjected to a natural ageing (shelf life) period of 15 days before undergoing retrogression at approximately 220°C/3 min, followed by re-ageing at 165°C for 2h. The heat-treated samples were evaluated using tensile testing, electrical conductivity in %IACS and high cycle fatigue testing after all proposed heat treatment cycles. The samples were further tested under high-cycle fatigue conditions. The results indicate that both tensile properties and electrical conductivity were adversely affected after the 15-day shelf life. Distinct differences in fatigue behavior were observed between the retrogression and T6 (re-ageing) treated alloys. The retrogression treatment for a short time for the samples after 15 days, exhibited an improvement of mechanical strength and electrical conductivity. However, re-aging of these samples for 165/2hr shows beak strength with decrease in electrical conductivity. Although, T6 condition provides superior strength, the Retrogression treatment offers high fatigue performance by improving crack growth resistance, making it a more suitable choice for applications requiring enhanced fatigue durability. Keywords: Retrogression and re-aging, Fatigue, Electrical conductivity, crack growth, Strength 

• English plays an important role in university study, academic communication, access to information, technology, and future employment. For many first-year students, however, the transition from school English to the language demands of university study can be challenging. This volume develops the core grammatical foundations required for first-year university English. The sequence begins with basic sentence structure and the verb to be, then develops through the present simple, questions and negatives, there is/there are, countable and uncountable nouns, and the past simple in affirmative, negative, and question forms. Each lecture is organised around explicit learning outcomes and combines explanation, examples, guided practice, vocabulary, reading, speaking, writing, review, and homework. The aim is not only to teach grammatical forms but also to help students use those forms to communicate about their studies, routines, experiences, plans, and academic life. Teachers may use the book as a core classroom text or adapt individual lectures to suit student level, contact hours, and local curriculum requirements. Students are encouraged to complete the exercises actively, speak and write whenever possible, review recurring errors, and build confidence through regular practice. 

Hereditary cancer syndromes (i.e. BRCA1/2-breast cancer) represent a small portion of around 6% of the population worldwide with genetic diseases, but their histopathological diagnosis is still difficult. In this paper, we present a clinical decision support system that combines an improved XGBoost classifier with SHapley Additive Explanations (SHAP) to provide high predictive accuracy and interpretable AI (XAI) in breast cancer diagnosis based on nuclear morphological features. The proposed approach employs a five-stage framework, namely: (1) Data collection from the Wisconsin Breast Cancer Diagnostic (WDBC) dataset, (2) missing value treatment by using multiple imputation by chained equations (MICE), (3) feature normalization, (4) biomarker selection using recursive feature elimination with cross validation (RFECV), and (5) class imbalance addressing by synthetic minority over-sampling technique (SMOTE). Hyperparameter tuning was done with Optuna using the Tree-structured Parzen Estimator (TPE) for 300 trials. The XGBoost model, evaluated on a test data consisting of 114 samples (20% of the total 569 samples), attained the highest accuracy of 96% and recall of 97% for class malignant, with a close to perfection ROC AUC of 0.99. SHAP results demonstrated that morphological characteristics (convex points and concavity, in particular) were the most important features, which is in line with histopathological understanding of nuclear alterations in hereditary cancer syndromes. Local waterfall plots ensured case-specific interpretability by breaking down single predictions into additive feature contributions. Although the WDBC dataset does not contain direct labels of genotype, the designed framework acts as a reproducible proof-of-concept for transparent, high-performance diagnosis of breast cancer with potential for application to hereditary syndromes, and veterinary histopathology incorporating appropriate species specific validation.

ABSTRACT

Background: Incisional hernia is a common complication following abdominal surgery, and mesh reinforcement has become

the standard of care. This study aimed to compare the clinical outcomes of sublay versus onlay mesh repair in patients with

incisional her

nia.

Methods: This prospective randomized controlled clinical trial was conducted at the General Surgery Department, Faculty

of Medicine, ..... Hospitals. A total of 60 patients diagnosed with incisional hernia and scheduled for elective surgical repai

r

were recr

uited from general surgery outpatient clinics and the emergency department. Patients were randomly assigned into

two equal groups: Group A (Onlay Group, n=30) underwent onlay mesh repair, and Group B (Sublay Group, n=30)

underwent sublay (retrorectus) mesh

repair. Baseline demographic, clinical, laboratory, and radiological characteristics were

recorded. Operative parameters, postoperative pain scores (Visual Analogue Scale), hospital stay, return to normal activity,

postoperative complications (seroma, hem

atoma, surgical site infection), and hernia recurrence at 12 months were compared

between the two groups.

Results: Operative time was significantly shorter in the onlay group (88.93 ± 7.93 minutes) compared to the sublay group

(99.67 ± 7.74 minutes) (p < 0.001). Postoperative pain scores were significantly lower in the sublay group at day 1 (4.70 ±

0.76 vs. 6.

10 ± 0.79), 1 week (2.39 ± 0.75 vs. 3.99 ± 0.82), 1 month (0.85 ± 0.74 vs. 2.41 ± 0.88), 3 months (0.30 ± 0.49 vs.

1.41 ± 0.86), 6 months (0.16 ± 0.36 vs. 1.02 ± 0.82), and 12 months (0.14 ± 0.48 vs. 0.82 ± 0.86) (p < 0.001 for all). Hospit

al

stay was sign

ificantly shorter in the sublay group (3.47 ± 1.11 days vs. 4.40 ± 0.93 days, p < 0.001), and return to normal

activity was significantly earlier (21.53 ± 3.41 days vs. 26.07 ± 4.73 days, p < 0.001). No significant difference was found

in drain removal day

(p = 0.257). Postoperative complications including seroma (10.0% vs. 23.3%, p = 0.299), hematoma

(3.3% vs. 6.7%, p = 1.000), and surgical site infection (6.7% vs. 16.7%, p = 0.424) were directionally lower in the sublay

group but did not reach statistical

significance. Hernia recurrence at 12 months was 3.3% in the sublay group versus 10.0%

in the onlay group (p = 0.612). All patients completed the 12

-

month follow

-

up.

Conclusion: Sublay (retrorectus) mesh repair offers significant clinical advantages over onlay mesh repair for incisional

hernia, including superior postoperative pain control, shorter hospital stay, and earlier return to normal activity. Postoper

ative

com

plications and recurrence showed consistent trends favoring sublay repair. These findings support sublay mesh repair as

the preferred technique for elective incisional hernia repair in appropriately selected patients.

.

Keywords

: Incisional hernia, mesh repair, sublay, retrorectus, onlay, postoperative pain, randomized controlled trial.