Factors Related to Student Performance in Statistics Courses in Lebanon

The purpose of the present study was to identify factors that may contribute to business students in Lebanese universities having difficulty in introductory and advanced statistics courses. Two statistics courses are required for business majors at Lebanese universities. Students are not obliged to be enrolled in any math courses prior to taking statistics courses. Drawing on recent educational research, this dissertation attempted to identify the relationship between (1) students’ scores on Lebanese university math admissions tests; (2) students’ scores on a test of very basic mathematical concepts; (3) students’ scores on the survey of attitude toward statistics (SATS); (4) course performance as measured by students’ final scores in the course; and (5) their scores on the final exam. Data were collected from 561 students enrolled in multiple sections of two courses: 307 students in the introductory statistics course and 260 in the advanced statistics course in seven campuses across Lebanon over one semester. The multiple regressions results revealed four significant relationships at the introductory level: between students’ scores on the math quiz with their (1) final exam scores; (2) their final averages; (3) the Cognitive subscale of the SATS with their final exam scores; and (4) their final averages. These four significant relationships were also found at the advanced level. In addition, two more significant relationships were found between students’ final average and the two subscales of Effort (5) and Affect (6). No relationship was found between students’ scores on the admission math tests and both their final exam scores and their final averages in both the introductory and advanced level courses. On the other hand, there was no relationship between students’ scores on Lebanese admissions tests and their final achievement. Although these results were consistent across course formats and instructors, they may encourage Lebanese universities to assess the effectiveness of prerequisite math courses. Moreover, these findings may lead the Lebanese Ministry of Education to make changes to the admissions exams, course prerequisites, and course content. Finally, to enhance the attitude of students, new learning techniques, such as group work during class meetings can be helpful, and future research should aim to test the effectiveness of these pedagogical techniques on students’ attitudes toward statistics

Study on the application of phototransferred thermoluminescence to reassessment of radiation dose using MCP-N and MTS-N detectors

The topic of a dissertation is to examine the impact of UV and thermal stimulation on the emission of thermoluminescence light using the PTTL (PhotoTransferred ThermoLuminescence) phenomenon, and consequently – the search for optimal stimulation conditions determining the accuracy of dose re-evaluation. Measurements were performed with the MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P) dosimeters exposed to electromagnetic radiation with dose up to 1000 mGy for MTS-N and up to 25 mGy for MCP-N detectors. Using the TLD Reader-Analyser RA’04 the dependence of PTTL data reading performance on UV wavelength, irradiation time and temperature of detectors during UV irradiation was examined. Among all available UV wavelengths (254, 302 and 365 nm) the highest efficiency occurred at λ = 254 nm. Further measurements were carried out with this wavelength. The light emission efficiency of the detectors using the PTTL phenomenon was tested with the following stimulation parameters: – UV irradiation time: from 30 minutes to 8 hours for MTS-N and from10 minutes to 4 hours for MCP-N detectors, and – a heating temperature during UV irradiation: from 33 to 140 °C for MTS-N and from 30 to 120 °C for MCP-N detectors. The most important results relate to the usefulness of the PTTL method for the dose re-evaluation: PTTL reading performance, detector linearity, and an indication of optimal conditions for UV irradiation and thermal treatment of detectors. Studies have shown that the high sensitivity of MCP-N detectors in routine measurements of TL dosimetry is lost at repeated readings in PTTL mode.Tematem rozprawy jest badanie wpływu parametrów stymulacji UV i termicznej na emisję światła z detektorów termoluminescencyjnych promieniowania jonizującego, z wykorzystaniem zjawiska termoluminescencji stymulowanej światłem (PTTL: PhotoTransferred ThermoLuminescence), a w konsekwencji – poszukiwanie warunków stymulacji optymalnych ze względu na dokładność ponownego (tzn. wykonywanego po pierwszym odczycie) wyznaczenia dawki. Pomiary były wykonywane z dozymetrami MTS-N (LiF:Mg,Ti) i MCP-N (LiF:Mg,Cu,P) napromieniowanymi promieniowaniem elektromagnetycznym o dawce do 1000 mGy dla MTS-N oraz do 25 mGy dla MCP-N. Za pomocą czytnika TLD Reader-Analyser RA’04 została zbadana zależność wydajności odczytu danych PTTL od długości fali promieniowania UV, czasu ekspozycji i temperatury detektorów w trakcie naświetlania UV. Spośród wszystkich dostępnych długości fal promieniowania UV (254, 302 i 365 nm) najwyższa wydajność detekcji wystąpiła przy λ = 254 nm. Dalsze pomiary były prowadzone ze stymulacją promieniowaniem UV o tej długości fali. Wydajność detekcji z wykorzystaniem zjawiska PTTL była badana przy następujących parametrach stymulacji: – czas ekspozycji na promieniowanie UV połączonej z nagrzewaniem detektorów: od 30 min. do 8 godz. dla detektorów MTS-N i od 10 min. do 4 godz. dla MCP-N, – temperatura ogrzewania w trakcie ekspozycji UV: od 33°C do 140°C dla detektorów MTS-N i od 30°C do 120°C dla MCP-N. Najważniejsze wyniki dotyczą przydatności metody PTTL do powtórnej oceny dawki: wyznaczenie wydajności odczytu PTTL, analiza liniowości wskazań detektorów, oraz wskazanie optymalnych warunków ekspozycji UV i obróbki termicznej detektorów TL. Badania wykazały, że wysoka czułość detektorów MCP-N w rutynowych pomiarach dozymetrycznych nie znajduje odzwierciedlenia w powtórnym odczycie, z wykorzystaniem zjawiska PTTL

On-line coupling of aptamer affinity solid-phase extraction and immobilized enzyme microreactor capillary electrophoresis-mass spectrometry for the sensitive targeted bottom-up analysis of protein biomarkers

In this paper, we present a fully integrated valve-free method for the sensitive targeted bottom-up analysis of proteins through on-line aptamer affinity solid-phase extraction and immobilized enzyme microreactor capillary electrophoresis-mass spectrometry (AA-SPE-IMER-CE-MS). The method was developed analyzing α-synuclein (α-syn), which is a protein biomarker related to different neurodegenerative disorders, including Parkinson's disease. Under optimized conditions, on-line purification and preconcentration of α-syn, enzymatic digestion, electrophoretic separation, and identification of the tryptic peptides by mass spectrometry was achieved in less than 35 min. The limit of detection was 0.02 μg mL-1 of digested protein (66.7% of coverage, i.e., 8 out of 12 expected tryptic peptides were detected). This value was 125 and 10 times lower than for independent on-line digestion by IMER-CE-MS (2.5 μg mL-1) and on-line preconcentration by AA-SPE-CE-MS (0.2 μg mL-1). The repeatability of AA-SPE-IMER-CE-MS was adequate (at 0.5 μg mL-1,% RSD ranged from 3.7 to 16.9% for peak areas and 3.5 to 7.7% for migration times of the tryptic peptides), and the modified capillary could be reused up to 10 analyses with optimum performance, similarly to IMER-CE-MS. The method was subsequently applied to the analysis of endogenous α-syn from red blood cell lysates. Ten α-syn tryptic peptides were detected (83.3% of coverage), enabling the characterization and localization of post-translational modifications of blood α-syn (i.e., N-terminal acetylation)

A review of sample preparation for purification of microRNAs and analysis by mass spectrometry methods

MicroRNAs (miRNAs) play an important role in regulation of different bioprocesses, including multiple diseases, such as cancer, neurodegenerative and immune-related disorders. Analysis of miRNA biomarkers in biological fluids requires accurate, sensitive, reproducible, and multiplexed methods. This review covers miRNA purification and measurement, which are the core of these analytical methods, and critically affect the output of biomarker research studies. With regard to miRNA measurement, the typical bioanalytical methods (e.g. reverse transcription polymerase chain reaction, RT-PCR), which have been extensively reviewed elsewhere, have been excluded to focus on less conventional methods based on mass spectrometry (MS). This review provides a broad overview of liquid-phase and solid-phase extraction purification methods for miRNA clean-up and enrichment and a critical insight into direct and indirect MS-based methods to disclose the true potential of MS in the field

Parental Attitude towards the Prescription of Psychotropic Medications for Mental Disorders in Children in a Tertiary Care University Hospital in Oman

Objectives: This study investigated parental attitudes towards psychotropic drugs for children's mental disorders. Methods: A questionnaire was distributed to parents of children attending a child psychiatry clinic at a tertiary hospital in Muscat, Oman. Similarly, in a small proportion, other caregivers filled out the questionnaire in case the child attended with them. The questionnaire comprised questions regarding parents' opinions, and attitudes about psychotropic medications use. The logistic regression model was used to identify the risk factors associated with parents who prefer to consult a folk healer (FH) for children with mental disorders. Results: A total of 299 parents agreed to participate in the study. The majority of them (81.6%, n=244) agreed that they would give their child psychotropic medications if necessary, but 25.4% of them (n=76) would consult a FH before consulting a psychiatrist if their child experienced psychiatric symptoms. Married parents were 14 times (OR=14.5, p=0.011) more likely to consult a FH than were separated or divorced parents. Caregivers with a monthly income below 500 OMR and between 500-1,000 OMR were two times (OR=2.5, p=0.016) and three times (OR=3.2, p<.001), respectively, more likely to consult a FH than those with a monthly income of more than 1,000 OMR. Parents who disagreed with giving psychotropic medications to their children were three times (OR=3.7, p<.001) more likely to consult a FH than were parents who agreed to give psychotropic medications to their children if necessary. Conclusion: Most parents agreed to give their children psychotropic medications if it were deemed necessary. However, a sizeable proportion of parents and caregivers preferred to consult a FH before accessing mental health services. Keywords: Parents; Children; Attitudes; Psychotropic Drugs; Oma

Fourth-generation glucose sensors composed of coppernanostructures for diabetes management: A critical review

More than five decades have been invested in understanding glucose biosensors. Yet, this immensely versatile field has continued to gain attention from the scientific world to better understand and diagnose diabetes. However, such extensive work done to improve glucose sensing devices has still not yielded desirable results. Drawbacks like the necessity of the invasive finger pricking step and the lack of optimization of diagnostic interventions still need to be considered to improve the testing process of diabetic patients. To upgrade the glucose-sensing devices and reduce the number of intermediary steps during glucose measurement, fourth-generation glucose sensors (FGGS) have been introduced. These sensors, made using robust electrocatalytic copper nanostructures, improve diagnostic efficiency and cost-effectiveness. This review aims to present the essential scientific progress in copper nanostructure-based FGGS in the past ten years (2010 – present). After a short introduction, we presented the working principles of these sensors. We then highlighted the importance of copper nanostructures as advanced electrode materials to develop reliable real-time FGGS. Finally, we cover the advantages, shortcomings, and prospects for developing highly sensitive, stable, and specific FGGS

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030