39 research outputs found
Maximum Likelihood Performance of Mean Time to Failure for Right-Censored Data
In this paper failure times following Weibull,
exponential and log-normal distribution are considered.
The parameters of these distributions are estimated
by the maximum likelihood method and these values
are used to estimate other quantity of interest such as
Mean Time to Failure (MTTF), an important function
in a reliability analysis. This study is to look at the
performance of maximum likelihood estimate (MLE)
under various conditions by considering varying sample
size and percentage of censored data. The performance
is quantified from the study
Kesan Faktor Jantina, Etnik Dan Gaya Kognitif Ke Atas Pencapaian Pengajian Am (The Effect Of Gender Ethnicity And Cognitive Styles On Achievement In General Paper)
Penyelidikan ini bertujuan untuk mengkaji kesan jantina, etnik dan gaya
kognitif ke atas pencapaian Pengajian Am dalam kalangan pelajar tingkatan enam.
Sampel kajian terdiri daripada 152 orang pelajar tingkatan enam atas (60 lelaki dan 92
perempuan) yang diambil dari sebuah sekolah terpilih di daerah Larut Matang dan
Selama, Perak. Sampel ini merangkumi pelajar yang berbangsa Melayu, Cina dan India.
Ujian GEFT (Group Embedded Figures Test) telah digunakan untuk mengukur gaya
kognitif pelajar manakala pencapaian mereka dalam mata pelajaran Pengajian Am pula
diukur dengan peperiksaan Sijil Tinggi Pelajaran Malaysia (STPM) tahun 2006. Dapatan
analisis ujian-t menunjukkan bahawa pelajar perempuan mempunyai pencapaian
Pengajian Am yang lebih baik secara signifikan berbanding dengan pelajar lelaki (t =
3.53, p < 0.05). Dari segi etnik pula, Analysis of Variance (ANOVA) menunjukkan
bahawa terdapat perbezaan yang signifikan dari segi pencapaian mengikut etnik. Namun,
analisis post-hoc membuktikan bahawa perbezaan yang signifikan hanya wujud antara
pelajar Melayu dan Cina sahaja. Hubungan antara gaya kognitif dengan pencapaian
Pengajian Am telah diuji melalui analisis korelasi Pearson. Kedua-dua variabel ini
didapati mempunyai hubungan yang positif dan signifikan (r = 0.15, p < 0.05). Keputusan
ANOVA dua hala seterusnya menunjukkan bahawa gaya kognitif tidak mempunyai kesan
interaksi yang signifikan dengan faktor jantina [F(1, 148) = 3.63, p > 0.05, eta squared
0.02] mahupun faktor etnik [F(2, 146) = 0.86, p > 0.05, eta squared = 0.01]. Kajian ini
mendapati bahawa pelajar perempuan mempunyai pencapaian yang lebih baik berbanding
dengan lelaki. Perbezaan pencapaian ini mungkin berpunca daripada faktor-faktor lain
kerana ia bukan disebabkan oleh perbezaan gaya kognitif mereka. Secara ringkasnya,
kajian ini menyumbang dari segi penyelidikan kerana ia membekalkan data empirikal
tentang psikologi dan pencapaian pelajar dalam mata pelajaran Pengajian Am yang jarang
dikaji oleh pengkaji tempatan. Selain daripada itu, maklumat kajian ini juga berguna
untuk para pendidik dan kaunselor sekolah dalam mengatur strategi untuk meningkatkan
pencapaian pelajar dalam Pengajian Am, sebuah mata pelajaran yang wajib di peringkat
tingkatan enam
Risk of metabolic syndrome among children living in metropolitan Kuala Lumpur: A case control study
Background With the increasing prevalence of childhood obesity, the metabolic syndrome has been studied among children in many countries but not in Malaysia. Hence, this study aimed to compare metabolic risk factors between overweight/obese and normal weight children and to determine the influence of gender and ethnicity on the metabolic syndrome among school children aged 9-12 years in Kuala Lumpur and its metropolitan suburbs. Methods A case control study was conducted among 402 children, comprising 193 normal-weight and 209 overweight/obese. Weight, height, waist circumference (WC) and body composition were measured, and WHO (2007) growth reference was used to categorise children into the two weight groups. Blood pressure (BP) was taken, and blood was drawn after an overnight fast to determine fasting blood glucose (FBG) and full lipid profile, including triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and total cholesterol (TC). International Diabetes Federation (2007) criteria for children were used to identify metabolic syndrome. Results Participants comprised 60.9% (n = 245) Malay, 30.9% (n = 124) Chinese and 8.2% (n = 33) Indian. Overweight/obese children showed significantly poorer biochemical profile, higher body fat percentage and anthropometric characteristics compared to the normal-weight group. Among the metabolic risk factors, WC ≥90th percentile was found to have the highest odds (OR = 189.0; 95%CI 70.8, 504.8), followed by HDL-C≤1.03 mmol/L (OR = 5.0; 95%CI 2.4, 11.1) and high BP (OR = 4.2; 95%CI 1.3, 18.7). Metabolic syndrome was found in 5.3% of the overweight/obese children but none of the normal-weight children (p < 0.01). Overweight/obese children had higher odds (OR = 16.3; 95%CI 2.2, 461.1) of developing the metabolic syndrome compared to normal-weight children. Binary logistic regression showed no significant association between age, gender and family history of communicable diseases with the metabolic syndrome. However, for ethnicity, Indians were found to have higher odds (OR = 5.5; 95%CI 1.5, 20.5) compared to Malays, with Chinese children (OR = 0.3; 95%CI 0.0, 2.7) having the lowest odds. Conclusions We conclude that being overweight or obese poses a greater risk of developing the metabolic syndrome among children. Indian ethnicity is at higher risk compared to their counterparts of the same age. Hence, primary intervention strategies are required to prevent this problem from escalating
Level of fear towards COVID-19 and its determinants among healthcare providers in Malaysia: A cross-sectional study
Introduction: Malaysia is one of the hardest-hit countries by COVID-19 in Asia. The rapidly rising number of cases had sparked fear among healthcare providers. This study aimed to assess the determinants of fear towards COVID-19 among healthcare providers in primary care settings.
Methods: This online-based cross-sectional study was conducted among 1280 healthcare providers aged ≥18 years from 30 primary care clinics in the state of Selangor, Malaysia. The Fear of COVID-19 Scale was used to assess the level of fear, and the results were analysed using multiple linear regression.
Results: The mean age of the respondents was 36 years, and the mean working experience was 11 years. The majority of the respondents were women (82.4%) and Malays (82.3%). The factors that were significantly correlated with higher levels of fear were underlying chronic disease (ß=1.12, P=0.002, 95% confidence interval [CI]=0.08, 3.15), concern about mortality from COVID-19 (ß=3.3, P<0.001, 95% CI=0.19, 7.22), higher risk of exposure (ß=0.8, P<0.001, 95% CI=0.14, 5.91), concern for self at work (ß=2.8, P=0.002, 95% CI=0.08, 3.10) and work as a nurse (ß=3.6, P<0.001, 95% CI=0.30, 7.52), medical laboratory worker (ß=3.0, P<0.001, 95% CI=0.12, 4.27) and healthcare assistant (ß=3.9, P<0.001, 95% CI=0.17, 5.73). The level of fear was inversely correlated with a higher work-related stress management score (ß=−0.9, P<0.001, 95% CI=−0.14, −5.07) and a higher sleep quality score (ß=−1.8, P<0.001, 95% CI=−0.28, −10.41).
Conclusion: Family physicians should be vigilant and identify healthcare providers at risk of developing COVID-19-related fear to initiate early mental health intervention
Ethnic differences in body fat distribution among Asian pre-pubertal children: A cross-sectional multicenter study
Background Ethnic differences in body fat distribution contribute to ethnic differences in cardiovascular morbidities and diabetes. However few data are available on differences in fat distribution in Asian children from various backgrounds. Therefore, the current study aimed to explore ethnic differences in body fat distribution among Asian children from four countries. Methods A total of 758 children aged 8-10 y from China, Lebanon, Malaysia and Thailand were recruited using a non-random purposive sampling approach to enrol children encompassing a wide BMI range. Height, weight, waist circumference (WC), fat mass (FM, derived from total body water [TBW] estimation using the deuterium dilution technique) and skinfold thickness (SFT) at biceps, triceps, subscapular, supraspinale and medial calf were collected. Results After controlling for height and weight, Chinese and Thai children had a significantly higher WC than their Lebanese and Malay counterparts. Chinese and Thais tended to have higher trunk fat deposits than Lebanese and Malays reflected in trunk SFT, trunk/upper extremity ratio or supraspinale/upper extremity ratio after adjustment for age and total body fat. The subscapular/supraspinale skinfold ratio was lower in Chinese and Thais compared with Lebanese and Malays after correcting for trunk SFT. Conclusions Asian pre-pubertal children from different origins vary in body fat distribution. These results indicate the importance of population-specific WC cut-off points or other fat distribution indices to identify the population at risk of obesity-related health problems
Six Strategies for Optimizing Linear Growth through Improving Awareness of Breastfeeding, Dietary Diversity in Complementary Feeding, and Growth Monitoring during Early Life
Only one-fourth of the countries under the Sustainable Development Goal are ‘on track’ to reduce the burden of malnutrition as of 2020. A deficit in linear growth during the first 5 years of life is mainly due to growth faltering in the first 1000 days. This deficit has been consistently reported to be linked to suboptimal cognitive neurodevelopment, while its improvement in early childhood has been reported to offer an opportunity for rescuing neurocognitive potential. This paper describes the perspectives of multidisciplinary experts, representing a range of disciplines related to child growth and nutrition, from Nigeria, Indonesia, and Malaysia, who convened virtually to review and discuss measures aimed at preventing a further increase in growth faltering, including stunting, among children aged 0-3 years under the current prevailing circumstances. Based on the latest evidence of practices and knowledge, the expert panel proposed six strategies to support linear growth in early life which consists of 2 new initiatives: 1) increasing peer-to-peer knowledge transfer among HCP via digital engagement; 2) increasing knowledge transfer from HCPs to caregivers via social media; while maintaining the existing strategies: 1) stimulating initiatives to support breastfeeding during the first 6 months of life; 2) improving quality of complementary feeding; 3) strengthening growth monitoring to detect suboptimal growth in early childhood; 4) optimizing public-private engagement. The recommended solutions presented herein are the culmination of the collective insights of the expert panel. These recommendations offer invaluable approaches on addressing the critical public health issue of malnutrition, specifically growth faltering, and can benefit not only the three countries concerned but also other low and middle-income countries facing similar nutritional challenges
Children’s and adolescents’ rising animal-source food intakes in 1990–2018 were impacted by age, region, parental education and urbanicity
Animal-source foods (ASF) provide nutrition for children and adolescents’ physical and cognitive development. Here, we use data from the Global Dietary Database and Bayesian hierarchical models to quantify global, regional and national ASF intakes between 1990 and 2018 by age group across 185 countries, representing 93% of the world’s child population. Mean ASF intake was 1.9 servings per day, representing 16% of children consuming at least three daily servings. Intake was similar between boys and girls, but higher among urban children with educated parents. Consumption varied by age from 0.6 at <1 year to 2.5 servings per day at 15–19 years. Between 1990 and 2018, mean ASF intake increased by 0.5 servings per week, with increases in all regions except sub-Saharan Africa. In 2018, total ASF consumption was highest in Russia, Brazil, Mexico and Turkey, and lowest in Uganda, India, Kenya and Bangladesh. These findings can inform policy to address malnutrition through targeted ASF consumption programmes.publishedVersio
Incident type 2 diabetes attributable to suboptimal diet in 184 countries
The global burden of diet-attributable type 2 diabetes (T2D) is not well established. This risk assessment model estimated T2D incidence among adults attributable to direct and body weight-mediated effects of 11 dietary factors in 184 countries in 1990 and 2018. In 2018, suboptimal intake of these dietary factors was estimated to be attributable to 14.1 million (95% uncertainty interval (UI), 13.8–14.4 million) incident T2D cases, representing 70.3% (68.8–71.8%) of new cases globally. Largest T2D burdens were attributable to insufficient whole-grain intake (26.1% (25.0–27.1%)), excess refined rice and wheat intake (24.6% (22.3–27.2%)) and excess processed meat intake (20.3% (18.3–23.5%)). Across regions, highest proportional burdens were in central and eastern Europe and central Asia (85.6% (83.4–87.7%)) and Latin America and the Caribbean (81.8% (80.1–83.4%)); and lowest proportional burdens were in South Asia (55.4% (52.1–60.7%)). Proportions of diet-attributable T2D were generally larger in men than in women and were inversely correlated with age. Diet-attributable T2D was generally larger among urban versus rural residents and higher versus lower educated individuals, except in high-income countries, central and eastern Europe and central Asia, where burdens were larger in rural residents and in lower educated individuals. Compared with 1990, global diet-attributable T2D increased by 2.6 absolute percentage points (8.6 million more cases) in 2018, with variation in these trends by world region and dietary factor. These findings inform nutritional priorities and clinical and public health planning to improve dietary quality and reduce T2D globally.publishedVersio
Measurements of photo-nuclear jet production in Pb plus Pb collisions with ATLAS
Ultra-peripheral heavy ion collisions provide a unique opportunity to study the parton distributions in the colliding
nuclei via the measurement of photo-nuclear jet production. An analysis of jet production in ultra-peripheral Pb+Pb
collisions at √sNN = 5.02 TeV performed using data collected with the ATLAS detector in 2015 is described. The data
set corresponds to a total Pb+Pb integrated luminosity of 0.38 nb−1. The ultra-peripheral collisions are selected using a
combination of forward neutron and rapidity gap requirements. The cross-sections, not unfolded for detector response,
are compared to results from Pythia Monte Carlo simulations re-weighted to match a photon spectrum obtained from
the STARlight model. Qualitative agreement between data and these simulations is observed over a broad kinematic
range suggesting that using these collisions to measure nuclear parton distributions is experimentally realisable
Heavy Ion Results from ATLAS
These proceedings provide an overview of the new results obtained with the ATLAS detector at the LHC, which were
presented in the Quark Matter 2017 conference. These results were covered by twelve parallel talks, one flash talk and
eleven posters. These proceedings group these results into five areas: initial state, jet quenching, quarkonium production,
longitudinal flow dynamics, and collectivity in small systems