71 research outputs found

    The Effect of the Solution Heat Treatment on the Mechanical Properties of Aluminum-Copper Alloy (2024-T3) Using Rolling Process

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    The effect of solution heat treatment on the mechanical properties of Aluminum-Copper alloy. (2024-T3) by the rolling process is investigated. The solution heat treatment was implemented by heating the sheets to 480 C° and quenching them by water; then forming by rolling for many passes. And then natural aging is done for one month. Mechanical properties (tensile strength and hardness) are evaluated and the results are compared with the metal without treatment during the rolling process. ANSYS analysis is used to show the stresses distribution in the sheet during the rolling process. It has been seen that good mechanical properties are evident in the alloy without heat treatment due to the strain hardening and also the mechanical properties are improved after heat treatment and rolling process but with lower forces and stresses when compared with the untreated

    Tualang honey supplement improves memory performance and hippocampal morphology in stressed ovariectomized rats

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    Recently, our research team has reported that Tualang honey was able to improve immediate memory in postmenopausal women comparable with that of estrogen progestin therapy. Therefore the aim of the present study was to examine the effects of Tualang honey supplement on hippocampal morphology and memory performance in ovariectomized (OVX) rats exposed to social instability stress. Female Sprague-Dawley rats were divided into six groups: (i) sham-operated controls, (ii) stressed shamoperated controls, (iii) OVX rats, (iv) stressed OVX rats, (v) stressed OVX rats treated with 17�-estradiol (E2), and (vi) stressed OVX rats treated with Tualang honey. These rats were subjected to social instability stress procedure followed by novel object recognition (NOR) test. Right brain hemispheres were subjected to Nissl staining. The number and arrangement of pyramidal neurons in regions of CA1, CA2, CA3 and the dentate gyrus (DG) were recorded. Two-way ANOVA analyses showed significant interactions between stress and OVX in both STM and LTM test as well as number of Nissl-positive cells in all hippocampal regions. Both E2 and Tualang honey treatments improved both short-term and long-term memory and enhanced the neuronal proliferation of hippocampal CA2, CA3 and DG regions compared to that of untreated stressed OVX rat

    Creating an engaging and stimulating anatomy lecture environment using the Cognitive Load Theory-based Lecture Model: Students' experiences

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    Objective: There is a need to create a standard interactive anatomy lecture that can engage students in their learning process. This study investigated the impact of a new lecturing guideline, the Cognitive Load Theory-based Lecture Model (CLT-bLM), on students’ cognitive engagement and motivation. Methods: A randomised controlled trial involving 197 participants from three institutions was conducted. The control group attended a freestyle lecture on the gross anatomy of the heart, delivered by a qualified anatomist from each institution. The intervention group attended a CLT-bLM-based lecture on a similar topic, delivered by the same lecturer, three weeks thereafter. The lecturers had attended a CLT-bLM workshop that allowed them to prepare for the CLT-bLM-based lecture over the course of three weeks. The students’ ratings on their cognitive engagement and internal motivation were evaluated immediately after the lecture using a validatedLearners’ Engagement and Motivation Questionnaire. The differences between variables were analysed and the results were triangulated with the focus group discussion findings that explored students’ experience while attending the lecture. Results: The intervention group has a significantly higher level of cognitive engagement than the control group; however, no significant difference in internal motivation score was found. In addition, the intervention group reported having a good learning experience from the lectures. Conclusion: The guideline successfully stimulated students’ cognitive engagement and learning experience, which indicates a successful stimulation of students’ germane resources. Stimulation of these cognitive resources is essential for successful cognitive processing, especially when learning a difficult subject such as anatomy

    Developing constructs of anatomy education environment measurement: A Delphi study

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    Inadequate anatomical knowledge due to unsatisfactory anatomy education environment has contributed to poor clinical performance among medical graduates. Unfortunately, no specific environment measurement tool is available. Delphi technique was conducted to identify the anatomy education environment components and their items. It involved identification of possible components and their definitions by nine anatomists which were then appraised and verified, getting critical appraisal from five medical educationists, determining suitable items for each component and finally appraised by content experts. Eleven components with 129 items that might represent the anatomy education environment were proposed. Further validation is required to determine its psychometric properties

    Gut microbiota in early life and its influence on health and disease: a position paper by the Malaysian Working Group on Gastrointestinal Health

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    The role of gut microbiota in early life and its impact on gut health and subsequent diseases remain unclear. There is a lack of research and awareness in this area, especially in the Asia-Pacific region, including Malaysia. This paper reports the position of a Malaysian Working Group on some key issues surrounding gut microbiota in early life and its role in gut health and diseases, as well as experts’ stand on probiotics and prebiotics. The group reached a consensus that certain factors, including elective caesarean; premature deliveries; complementary feeding; use of antibiotics, prebiotics and/or probiotics; and exposure to the external environmental, have an impact on gut microbiota in early life. However, as evidence is lacking, especially from the Asia-Pacific region, further studies are needed to understand how gut microbiota in early life affects subsequent diseases, including allergy, inflammatory bowel disease, obesity and infantile colic. Lastly, although beneficial in acute diarrhoeal disease and probably allergic eczema, probiotics (and/or prebiotics) should be used cautiously in other gut dysbiotic conditions until more data are available

    Knowledge, attitude and practice about leptospirosis prevention among town service workers in northeastern Malaysia: a cross sectional study

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    Introduction. Many efforts have been done to reduce leptospirosis infections in Malaysia especially among high risk groups including town service workers. Town service workers are more likely to be exposed to the leptospiral infection resulting from their occupational activities.Methods. A cross sectional study was conducted in northeastern Malaysia involving 321 town service workers who were subjected to answer an interviewer-guided validated questionnaire which consists of sociodemographic, knowledge, attitude and practice information. Data were entered and analyzed using SPSS Version 20.Results. All of the respondents were Malay with mean (SD) age of 40.6 (10.28) years old. The mean (SD) duration of employment was 12.1 (9.62) years. Fifty four respondents (16.8%) had never heard of leptospirosis. Among the respondents, 215 (67.0%) of them had poor knowledge on leptospirosis. Meanwhile, 167 (52.0%) and only 128 (39.9%) of them had satisfactory attitude and practice respectively. It was found that knowledge on risk factors for leptospirosis was lacking. There were high risk attitudes such as drinking habit and protective equipment used during working with the favourable answers ranged from 67.3% to 89.1%. The weakest area identified in their practice was also on the use of protective equipment.Conclusions. The workers’ level of knowledge and practice were relatively poor despite an overall good practice on leptospirosis. This finding might expose them to an increased risk of contracting leptospirosis. Identified weak areas in their knowledge, attitude and practice will assist the policy makers to develop a focused and well-directed intervention program on leptospirosis infection. 

    Evaluation of toxicity and antibacterial activities of Andrographis paniculata herbal mouthwash against oral pathogens

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    Andrographis paniculata (AP) is an ancient herb known for its medicinal and therapeutic values. In this study, we aimed to evaluate the antibacterial activity and cytotoxicity of AP herbal mouthwash. Aqueous extract of AP was used to prepare the herbal mouthwash. The product was tested against selected oral pathogens namely Actinomyeces viscosus, Staphylococcus aureus, Streptococcus mutans, Streptococcus sobrinus, and Porphyromonas gingivalis for its antibacterial activity using the agar well diffusion method. Toxicity analysis was carried out and subjected to cytotoxicity screening using 3-(4,5-dimethylthiazol-2- yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, in vivo study using brine shrimp lethality bioassay, and detection of heavy metals using atomic absorption spectroscopy (AAS). Five AP herbal mouthwash concentrations (62.5, 125, 250, 500, 1000 mg/mL) were developed. AP herbal mouthwash exhibited the strongest antibacterial activity against A. viscosus. AP herbal mouthwash (125 to 1000 mg/mL) showed inhibition against P. gingivalis, S. mutans and S. sobrinus, except for S. aureus which did not reflect any sign of antibacterial activity. In brine shrimp lethality bioassay, AP herbal mouthwash has LC50 3255.064 µg/ mL. In vitro cytotoxic evaluation was done on L929 mouse fibroblast cell lines using MTT assay with IC50 43.55 mg/mL denotes the mouthwash is non-toxic. Heavy metals content in AP herbal mouthwash falls within the permissible range of plumbum (2.50 ppm) followed by arsenic (1.875 ppm), mercury (0.15 ppm), and cadmium (0.06 ppm). Thus, verifying AP herbal mouthwash is effective in common oral pathogens and has a non-toxic effect

    Anatomy education environment measurement inventory (AEEMI): a cross-validation study in Malaysian medical schools

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    Background: The Anatomy Education Environment Measurement Inventory (AEEMI) evaluates the perception of medical students of educational climates with regard to teaching and learning anatomy. The study aimed to cross-validate the AEEMI, which was previously studied in a public medical school, and proposed a valid universal model of AEEMI across public and private medical schools in Malaysia. Methods: The initial 11-factor and 132-item AEEMI was distributed to 1930 pre-clinical and clinical year medical students from 11 medical schools in Malaysia. The study examined the construct validity of the AEEMI using exploratory and confirmatory factor analyses. Results: The best-fit model of AEEMI was achieved using 5 factors and 26 items (χ 2 = 3300.71 (df = 1680), P < 0.001, χ 2/df = 1.965, Root Mean Square of Error Approximation (RMSEA) = 0.018, Goodness-of-fit Index (GFI) = 0.929, Comparative Fit Index (CFI) = 0.962, Normed Fit Index (NFI) = 0.927, Tucker–Lewis Index (TLI) = 0.956) with Cronbach’s alpha values ranging from 0.621 to 0.927. Findings of the cross-validation across institutions and phases of medical training indicated that the AEEMI measures nearly the same constructs as the previously validated version with several modifications to the item placement within each factor. Conclusions: These results confirmed that variability exists within factors of the anatomy education environment among institutions. Hence, with modifications to the internal structure, the proposed model of the AEEMI can be considered universally applicable in the Malaysian context and thus can be used as one of the tools for auditing and benchmarking the anatomy curriculum

    Association of respiratory symptoms and lung function with occupation in the multinational Burden of Obstructive Lung Disease (BOLD) study

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    Background Chronic obstructive pulmonary disease has been associated with exposures in the workplace. We aimed to assess the association of respiratory symptoms and lung function with occupation in the Burden of Obstructive Lung Disease study. Methods We analysed cross-sectional data from 28 823 adults (≥40 years) in 34 countries. We considered 11 occupations and grouped them by likelihood of exposure to organic dusts, inorganic dusts and fumes. The association of chronic cough, chronic phlegm, wheeze, dyspnoea, forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1)/FVC with occupation was assessed, per study site, using multivariable regression. These estimates were then meta-analysed. Sensitivity analyses explored differences between sexes and gross national income. Results Overall, working in settings with potentially high exposure to dusts or fumes was associated with respiratory symptoms but not lung function differences. The most common occupation was farming. Compared to people not working in any of the 11 considered occupations, those who were farmers for ≥20 years were more likely to have chronic cough (OR 1.52, 95% CI 1.19–1.94), wheeze (OR 1.37, 95% CI 1.16–1.63) and dyspnoea (OR 1.83, 95% CI 1.53–2.20), but not lower FVC (β=0.02 L, 95% CI −0.02–0.06 L) or lower FEV1/FVC (β=0.04%, 95% CI −0.49–0.58%). Some findings differed by sex and gross national income. Conclusion At a population level, the occupational exposures considered in this study do not appear to be major determinants of differences in lung function, although they are associated with more respiratory symptoms. Because not all work settings were included in this study, respiratory surveillance should still be encouraged among high-risk dusty and fume job workers, especially in low- and middle-income countries.publishedVersio

    Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey

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    Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10&nbsp;years; 78.2% included were male with a median age of 37&nbsp;years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
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