Finite Element Modelling of Creep Rupture on Grade 91 Steel using Monkman-Grant Ductility based Damage Model

Failure strain is a main parameter used in the ductility exhaustion based damage model in which the accuracy of the prediction is dependent on its input value. The experimental measured has indicated that the value of strain at fracture is extensively scattered, therefore may affect the prediction. This paper presents the result of creep rupture time using a modified creep damage model incorporating Monkman-Grant (MG) failure strain as an alternative to strain at fracture. Both strains at fracture and MG failure strain are separately employed in the damage model to predict the failure time of uniaxial smooth specimen and notched bar with different acuity ratios of 3.0 and 20. The FE model of the specimen is loaded under different stress values and the multiaxial failure strain at each stress level is estimated using Cock and Ashby void growth model. The predicted creep rupture time that is compared to the experimental data (in a range of 40-1000 hours) showing a good agreement within the scatter band of +/- factor of 2. Both approaches using strain at fracture and MG failure strain can be used in predicting the creep failure under uniaxial and multiaxial features. The advantage of using MG strain is that the laboratory creep testing can be interrupted prior to specimen fractured or once the secondary creep deformation occurs. Meanwhile, the determination of strain at fracture needs longer test duration where the test can be stopped only when the specimen broken

Finite Element Modelling of Creep Rupture on Grade 91 Steel using Monkman-Grant Ductility based Damage Model

Failure strain is a main parameter used in the ductility exhaustion based damage model in which the accuracy of the prediction is dependent on its input value. The experimental measured has indicated that the value of strain at fracture is extensively scattered, therefore may affect the prediction. This paper presents the result of creep rupture time using a modified creep damage model incorporating Monkman-Grant (MG) failure strain as an alternative to strain at fracture. Both strains at fracture and MG failure strain are separately employed in the damage model to predict the failure time of uniaxial smooth specimen and notched bar with different acuity ratios of 3.0 and 20. The FE model of the specimen is loaded under different stress values and the multiaxial failure strain at each stress level is estimated using Cock and Ashby void growth model. The predicted creep rupture time that is compared to the experimental data (in a range of 40-1000 hours) showing a good agreement within the scatter band of +/- factor of 2. Both approaches using strain at fracture and MG failure strain can be used in predicting the creep failure under uniaxial and multiaxial features. The advantage of using MG strain is that the laboratory creep testing can be interrupted prior to specimen fractured or once the secondary creep deformation occurs. Meanwhile, the determination of strain at fracture needs longer test duration where the test can be stopped only when the specimen broken

Responses of tropical fruit bats to monoculture and polyculture farming in oil palm smallholdings

The oil palm industry is one of the main economic drivers in Southeast Asia. The industry has caused tropical deforestation on a massive scale in producing countries, and this forest conversion to oil palm agriculture has decimated the habitat of numerous native species. Monoculture and polyculture practices are two distinctive oil palm production systems. We hypothesize that polyculture farming hosts a greater diversity of species than monoculture farming. Habitat complexity in smallholdings is influenced by multiple farming practices (i.e. polyculture and monoculture). However, little is known about the effects of such farming practices in smallholdings on mammalian biodiversity, and particularly frugivorous bats. Our study aimed to find the best farming practice to reconcile oil palm production with biodiversity conservation. Mist-nets were used to trap frugivorous bats at 120 smallholdings in Peninsular Malaysia. We compared species richness and the abundance of frugivorous bats between monoculture and poly-culture smallholdings. We investigated their relationships with vegetation structure characteristics. Our results revealed that species richness and abundance of frugivorous bats were significantly greater in polyculture smallholdings than monoculture smallholdings. We also found that 28.21% of the variation in species richness was explained by in situ habitat characteristics, including the number of dead standing oil palms and immature oil palms, non-grass cover, height of non-grass cover, and farming practices. Thein situ habitat quality was closely associated with oil palm farming management. Commercial growers should implement polyculture rather than monoculture farming because polyculture farming has positive effects on the abundance and species richness of bats in oil palm production landscapes

Dynamic mechanical properties and thermal properties of longitudinal basalt/woven glass fiber reinforced unsaturated polyester hybrid composites

This study investigates the mechanical, thermal, and chemical properties of basalt/woven glass fiber reinforced polymer (BGRP) hybrid polyester composites. The Fourier transform infrared spectroscopy (FTIR) was used to explore the chemical aspect, whereas the dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA) were performed to determine the mechanical and thermal properties. The dynamic mechanical properties were evaluated in terms of the storage modulus, loss modulus, and damping factor. The FTIR results showed that incorporating single and hybrid fibers in the matrix did not change the chemical properties. The DMA findings revealed that the B7.5/G22.5 composite with 7.5 wt% of basalt fiber (B) and 22.5 wt% of glass fiber (G) exhibited the highest elastic and viscous properties, as it exhibited the higher storage modulus (8.04 × 109 MPa) and loss modulus (1.32 × 109 MPa) compared to the other samples. All the reinforced composites had better damping behavior than the neat matrix, but no further enhancement was obtained upon hybridization. The analysis also revealed that the B22.5/G7.5 composite with 22.5 wt% of basalt fiber and 7.5 wt% of glass fiber had the highest Tg at 70.80◦C, and increased by 15◦C compared to the neat matrix. TMA data suggested that the reinforced composites had relatively low dimensional stabilities than the neat matrix, particularly between 50 to 80◦C. Overall, the hybridization of basalt and glass fibers in unsaturated polyester formed composites with higher mechanical and thermal properties than single reinforced composites

Mechanical properties of longitudinal basalt/woven-glass-fiber-reinforced unsaturated polyester-resin hybrid composites

This work represents a study to investigate the mechanical properties of longitudinal basalt/woven-glass-fiber-reinforced unsaturated polyester-resin hybrid composites. The hybridization of basalt and glass fiber enhanced the mechanical properties of hybrid composites. The unsaturated polyester resin (UP), basalt (B) and glass fibers (GF) were fabricated using the hand lay-up method in six formulations (UP, GF, B7.5/G22.5, B15/G15, B22.5/G7.5 and B) to produce the composites, respectively. This study showed that the addition of basalt to glass-fiber-reinforced unsaturated polyester resin increased its density, tensile and flexural properties. The tensile strength of the B22.5/G7.5 hybrid composites increased by 213.92 MPa compared to neat UP, which was 8.14 MPa. Scanning electron microscopy analysis was used to observe the fracture mode and fiber pullout of the hybrid composites

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

Impak pelancongan terhadap kualiti hidup bandar: perspektif penduduk Putrajaya

Pelancongan memainkan peranan penting dalam menentukan tahap kualiti hidup atau kesejahteraan penduduk di sesebuah bandar. Kajian menunjukkan bahawa pelancongan boleh diterima secara positif oleh penduduk apabila mereka mendapat faedah daripada aktiviti pelancongan yang dijalankan. Artikel ini bertujuan menilai persepsi penduduk di Putrajaya terhadap pembangunan pelancongan sama ada mereka telah mendapat manfaat atau sebaliknya, dan seterusnya mempengaruhi tahap kualiti hidup mereka. Satu kajian dijalankan ke atas 200 responden penduduk yang menetap di Putrajaya. Lima petunjuk kualiti hidup telah digunakan dalam mengenal pasti tahap kesejahteraan penduduk - kebendaan/ekonomi, emosi, sosial dan budaya, komuniti dan alam sekitar, kesihatan dan keselamatan. Kajian ini mendapati bahawa kesejahteraan emosi memperoleh purata min tertinggi iaitu 3.62 dan antara faktor tersebut ialah penerimaan kedatangan pelancong tanpa menjejaskan keselesaan dan kebahagiaan penduduk tempatan. Sementara itu, kesejahteraan kebendaan/ekonomi memperoleh purata min sebanyak 2.67, bermakna pelancongan hanya memberikan impak minimum daripada segi kesejahteraan penduduk. Ini kerana, majoriti penduduk merasakan bahawa mereka tidak terlibat secara aktif dalam perniagaan dan aktiviti pelancongan keusahawanan. Kesimpulannya, kajian ini telah membuktikan pelancongan sememangnya mempengaruhi kualiti hidup penduduk yang tinggal di Putrajaya. Dengan usaha yang lebih bersepadu dan inklusif, Putrajaya akan menjadi salah satu contoh untuk mempromosi penyertaan penduduk bandar dalam aktiviti pelancongan

Navigating puberty with special needs teenagers: empowering parents through a sexuality education workshop

Adolescence is a crucial phase of development, marked by significant physical, emotional, and social changes. Navigating these changes for teenagers with special needs can be particularly challenging. Addressing these topics is essential to ensure holistic well-being and healthy development of teenagers with special needs. This workshop aimed to equip parents with the necessary knowledge, skills, and strategies to navigate conversations about puberty and sexuality effectively. This paper is to present the findings of this workshop focused on puberty and sexuality education for parents of teenagers with special needs. A diverse group of parents of teenagers with special needs were recruited through Facebook groups, special schools, and community organizations. Prior to the workshop participants were invited to answer questions regarding their concerns about their special needs child sexuality. A total of 150 parents responded to this qualitative survey. The workshop includes a slot for a sexuality education lecture and a hands-on practical session focusing on managing menstruation and masturbation. A total of 69 participants for the workshop were required to answer pre and post-questionnaires – to determine the knowledge, perceptions, dedication, and willingness in delivering sexual information to teenagers with special needs

Hormone consumption among Mak Nyahs in Kuantan Town: A preliminary survey

Introduction: Mak nyahs (male-to-female transgenders) often consume feminizing hormones to achieve and maintain the female physical appearance. They do it without professional prescription/advise, and often take excessive doses. This renders them at risk of developing complications of hormone consumption. This paper provides some quantitative data on hormone consumption among mak nyahs in Kuantan, Pahang, in Malaysia. Materials and Methods: A cross-sectional study was carried out from July to August in 2015 among 35 mak nyahs. Convenience sampling was used. Participants who gave consent answered an interview-guided questionnaire which documents socio-demographic profile, hormone usage, and morbidities as a result of hormone consumption. Data was analysed using SPSS, Version 16.0. (version 16). Results: Majority of the subjects were Malays (91.4%) and Muslims (97.1%), their median (IQR) age being 31 (±17) years, more than half (57.1%) were between 20 to 40 years old. Most (80.0%) of them are sex workers. Oral hormone was most commonly used (88.6%), while more than half (67.7%) of them added hormone injections. Almost all subjects purchased hormones over the counter from local pharmacies (94.2%). However, many received information on hormone from non-professional sources. Possible adverse effects of hormones reported among subjects were hypertension, ischemic heart disease, diabetes mellitus, and venous thrombo-embolism. Conclusion: Hormone consumption was very common among the subjects in this study, and may be associated with certain medical problems. Medical personnel must pay more attention in educating the mak nyahs on adverse effects of hormones consumption. Mak nyahs should also be screened for complications every time they seek medical attention

The impact of movement control order on rural livelihood in Malaysia

In 2020, the spread of Coronavirus (COVID-19) had a global impact on normal daily life. The Government of Malaysia officially declared the Movement Control Order (MCO), an official national lockdown, to reduce the virus’s spread. In the face of the unprecedented global health pandemic, Malaysia had struggled to protect its citizens’ welfare and livelihoods, particularly in the hardest-hit rural areas. Therefore, this study uses the sustainable livelihood approach (SLA) focusing on the aspect of financial assets and government intervention to enhance understanding on the vulnerability in rural area’s livelihood. Pasir Puteh, Kelantan was identified as the rural area for this study. The analysis was performed on a questionnaire survey based on convenience sampling of 62 respondents. Cross table analysis and a correlation test were used to examine the livelihood of the rural area concerning the financial assets, government intervention and vulnerability. The findings indicated that the MCO had a substantial impact on the rural area regarding the vulnerability toward the financial assets, such as employment status, job loss, increasing living costs, and an insufficient response to rural economic challenges. At the same time, there is no substantial government intervention in the welfare of rural areas. According to the results, the study concluded that the government should set up training courses to assist in the long-term recovery of rural areas due to the enforced lockdown, which has adversely affected rural livelihoods