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1.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-1012675

RESUMO

@#Introduction: Ergonomics is the scientific study of the interactions between humans and other elements of a system to improve human well-being and overall system performance. In larger scope ergonomics examines human behavioral, psychological, and physiological capabilities and limitations. It has given a huge impact on the workers comfort which directly affects the work efficiency and productivity. In Malaysia, the electronics industry is the leading industry in the manufacturing sector and one of the largest employers. This study was conducted to examine the relationship between ergonomics factors and job performance among employees in electronics industry. Material and Method: A total of 155 employees in electronic industry were involved as respondents in this study. A cross-sectional study was conducted using self-administered questionnaires consisting of sections on physical ergonomics, cognitive ergonomics, and organizational ergonomics and job performance. The data were analysed using SPSS version 25, and descriptive statistics, person correlation and multiple liner regressions were used to identify the factors associated with job performance. Results: The findings showed that there is a significant relationship between ergonomics factors (physical ergonomics, cognitive ergonomics, and organizational ergonomics) and employee performance with p<0.05. While the multiple linear regression analysis found that the most contributing ergonomics factors was physical ergonomics that significantly affects job performance in the electronics industry in Malaysia. Conclusion: Ergonomics factors can be used to promote improved performance and productivity from the employees in the organization such as awareness training and education.

2.
Biomol NMR Assign ; 17(2): 249-255, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37668860

RESUMO

Spider dragline silk has attracted great interest due to its outstanding mechanical properties, which exceed those of man-made synthetic materials. Dragline silk, which is composed of at least major ampullate spider silk protein 1 and 2 (MaSp1 and MaSp2), contains a long repetitive domain flanked by N-terminal and C-terminal domains (NTD and CTD). Despite the small size of the CTD, this domain plays a crucial role as a molecular switch that regulates and directs spider silk self-assembly. In this study, we report the 1H, 13C, and 15N chemical shift assignments of the Latrodectus hesperus MaSp2 CTD in dimeric form at pH 7. Our solution NMR data demonstrated that this protein contains five helix regions connected by a flexible linker.


Assuntos
Fibroínas , Aranhas , Humanos , Animais , Ressonância Magnética Nuclear Biomolecular , Fibroínas/química , Seda/química , Seda/metabolismo , Espectroscopia de Ressonância Magnética , Aranhas/metabolismo
3.
Methods Mol Biol ; 2702: 3-12, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37679612

RESUMO

The application of antibodies has transcended across many areas of work but mainly as a research tool, for diagnostic and for therapeutic applications. Antibodies are immunoproteins from vertebrates that have the unique property of specifically binding foreign molecules and distinguish target antigens. This property allows antibodies to effectively protect the host from infections. Apart from the hybridoma technology using transgenic animals, antibody phage display is commonly considered the gold standard technique for the isolation of human monoclonal antibodies. The concept of antibody phage display surrounds the ability to display antibody fragments on the surface of M13 bacteriophage particles with the corresponding gene packaged within the particle. A repetitive in vitro affinity based selection process permits the enrichment of target specific binders. This process of recombinant human monoclonal antibody generation also enables additional engineering for various applications. This makes phage display an indispensable technique for antibody development and engineering activities.


Assuntos
Anticorpos Monoclonais , Bacteriófago M13 , Animais , Humanos , Anticorpos Monoclonais/genética , Animais Geneticamente Modificados , Técnicas de Visualização da Superfície Celular , Hibridomas
4.
Polymers (Basel) ; 15(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36904513

RESUMO

Textile industrialization causes water pollution due to the discharge of industrial effluents into the environment. To reduce the impact of industrial effluent, it must be treated in wastewater treatment plants before discharge into rivers. Among all wastewater treatment approaches, the adsorption process is one method to remove pollutants from wastewater, but it has some limitations in term of reusability and ionic selective adsorption properties. In this study, we prepared cationic poly (styrene sulfonate) (PSS)-incorporated anionic chitosan beads synthesized using the oil-water emulsion coagulation method. The produced beads were characterized using FESEM and FTIR analysis. In batch adsorption studies, the PSS-incorporated chitosan beads exhibited monolayer adsorption processes, that is, exothermic processes that occur spontaneously at low temperatures, which were analyzed based on the adsorption isotherms, adsorption kinetics, and thermodynamics model fittings. The presence of PSS enables cationic methylene blue dye to adsorb to the anionic chitosan structure via electrostatic interaction between the sulfonic group and the dye molecule. The maximum adsorption capacity of PSS-incorporated chitosan beads achieved 42.21 mg/g, as calculated from the Langmuir adsorption isotherm. Finally, the PSS-incorporated chitosan beads demonstrated good regeneration with different types of reagents, especially using sodium hydroxide as a regeneration reagent. With the use of sodium hydroxide regeneration of this adsorbent material, a continuous adsorption setup also demonstrated that PSS-incorporated chitosan beads can be reused for methylene blue adsorption for up to three cycle processes.

5.
Biomacromolecules ; 24(4): 1604-1616, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36990448

RESUMO

Spider dragline silk is a remarkably tough biomaterial and composed primarily of spidroins MaSp1 and MaSp2. During fiber self-assembly, the spidroin N-terminal domains (NTDs) undergo rapid dimerization in response to a pH gradient. However, obtaining a detailed understanding of this mechanism has been hampered by a lack of direct evidence regarding the protonation states of key ionic residues. Here, we elucidated the solution structures of MaSp1 and MaSp2 NTDs from Trichonephila clavipes and determined the experimental pKa values of conserved residues involved in dimerization using NMR. Surprisingly, we found that the Asp40 located on an acidic cluster protonates at an unusually high pH (∼6.5-7.1), suggesting the first step in the pH response. Then, protonation of Glu119 and Glu79 follows, with pKas above their intrinsic values, contributing toward stable dimer formation. We propose that exploiting the atypical pKa values is a strategy to achieve tight spatiotemporal control of spider silk self-assembly.


Assuntos
Fibroínas , Aranhas , Animais , Fibroínas/química , Seda/química , Dimerização , Espectroscopia de Ressonância Magnética , Aranhas/metabolismo
6.
Int. microbiol ; 26(1): 91-98, Ene. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-215920

RESUMO

Paddy is an important crop in Malaysia. There are various pathogens able to infect paddy causing a loss in yield’s production. In this study, dual culture method, volatile organic compound (VOC) analysis, and non-volatile compound analysis were used to assess the ability of mushroom to control fungal rice pathogens including Curvularia lunata, Bipolaris panici-miliacei, and Nigrospora sp. Four mushroom isolates were further analysed for their antagonistic activity against rice pathogen. The highest percentage inhibition of radial growth (PIRG) was recorded between 45.55 and 73.68% observed in isolate 42b. The 4 isolates with the highest PIRG based on the dual culture analysis were then tested for their production of VOCs and non-volatile compound. Internal transcribed spacer (ITS) region analysis of the 4 mushroom isolates revealed their identity as Coprinellus disseminates (isolate 12b), Marasmiellus palmivorus (isolate 42b), Trametes maxima (isolate 56e), and Lentinus sajor-caju (isolate 60a). This study showed that mushroom isolates have the potential of antagonistic effect on various fungal rice pathogens tested by the production of secondary metabolites and mycoparasitic interaction.(AU)


Assuntos
Humanos , Oryza , Agaricales , Compostos Orgânicos Voláteis , Micotoxicose , Genes Fúngicos , Microbiologia , Malásia
7.
Int Microbiol ; 26(1): 91-98, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36089618

RESUMO

Paddy is an important crop in Malaysia. There are various pathogens able to infect paddy causing a loss in yield's production. In this study, dual culture method, volatile organic compound (VOC) analysis, and non-volatile compound analysis were used to assess the ability of mushroom to control fungal rice pathogens including Curvularia lunata, Bipolaris panici-miliacei, and Nigrospora sp. Four mushroom isolates were further analysed for their antagonistic activity against rice pathogen. The highest percentage inhibition of radial growth (PIRG) was recorded between 45.55 and 73.68% observed in isolate 42b. The 4 isolates with the highest PIRG based on the dual culture analysis were then tested for their production of VOCs and non-volatile compound. Internal transcribed spacer (ITS) region analysis of the 4 mushroom isolates revealed their identity as Coprinellus disseminates (isolate 12b), Marasmiellus palmivorus (isolate 42b), Trametes maxima (isolate 56e), and Lentinus sajor-caju (isolate 60a). This study showed that mushroom isolates have the potential of antagonistic effect on various fungal rice pathogens tested by the production of secondary metabolites and mycoparasitic interaction.


Assuntos
Agaricales , Oryza , Trametes , Malásia
8.
Nanomaterials (Basel) ; 12(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35889589

RESUMO

The development of carbon dots (CDs), either using green or chemical precursors, has inevitably led to their wide range application, from bioimaging to optoelectronic devices. The reported precursors and properties of these CDs have opened new opportunities for the future development of high-quality CDs and applications. Green precursors were classified into fruits, vegetables, flowers, leaves, seeds, stem, crop residues, fungi/bacteria species, and waste products, while the chemical precursors were classified into acid reagents and non-acid reagents. This paper quickly reviews ten years of the synthesis of CDs using green and chemical precursors. The application of CDs as sensing materials in optical sensor techniques for environmental monitoring, including the detection of heavy metal ions, phenol, pesticides, and nitroaromatic explosives, was also discussed in this review. This profound review will offer knowledge for the upcoming community of researchers interested in synthesizing high-quality CDs for various applications.

9.
BMC Med Educ ; 22(1): 544, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35836223

RESUMO

BACKGROUND: The popularity of mobile health (mHealth) applications (or apps) in the field of health and medical education is rapidly increasing, especially since the COVID-19 pandemic. We aimed to assess awareness, attitudes, practices, and factors associated with the mHealth app usage among medical students. METHODS: We conducted a cross-sectional study involving medical students at a government university in Sarawak, Malaysia, from February to April 2021. Validated questionnaires were administered to all consenting students. These questionnaires included questions on basic demographic information as well as awareness, attitude toward, and practices with mHealth apps concerned with medical education, health and fitness, and COVID-19 management. RESULTS: Respondents had favorable attitudes toward mHealth apps (medical education [61.8%], health and fitness [76.3%], and COVID-19 management [82.7%]). Respondents' mean attitude scores were four out of five for all three app categories. However, respondents used COVID-19 management apps more frequently (73.5%) than those for medical education (35.7%) and fitness (39.0%). Usage of all three app categories was significantly associated with the respondent's awareness and attitude. Respondents in the top 20% in term of household income and study duration were more likely to use medical education apps. The number of respondents who used COVID-19 apps was higher in the top 20% household income group than in the other income groups. The most common barrier to the use of apps was uncertainty regarding the most suitable apps to choose. CONCLUSION: Our study highlighted a discrepancy between awareness of mHealth apps and positive attitudes toward them and their use. Recognition of barriers to using mHealth apps by relevant authorities may be necessary to increase the usage of these apps.


Assuntos
COVID-19 , Aplicativos Móveis , Estudantes de Medicina , Telemedicina , Atitude , COVID-19/epidemiologia , Estudos Transversais , Humanos , Malásia , Pandemias
10.
Nanomaterials (Basel) ; 12(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35683655

RESUMO

Abnormality of dopamine (DA), a vital neurotransmitter in the brain's neuronal pathways, causes several neurological diseases. Rapid and sensitive sensors for DA detection are required for early diagnosis of such disorders. Herein, a carbon quantum dot (CQD)-based refractive index surface plasmon resonance (SPR) sensor was designed. The sensor performance was evaluated for various concentrations of DA. Increasing DA levels yielded blue-shifted SPR dips. The experimental findings revealed an excellent sensitivity response of 0.138°/pM in a linear range from 0.001 to 100 pM and a high binding affinity of 6.234 TM-1. The effects of varied concentrations of DA on the optical characteristics of CQD thin film were further proved theoretically. Increased DA levels decreased the thickness and real part of the refractive index of CQD film, according to fitting results. Furthermore, the observed reduction in surface roughness using AFM demonstrated that DA was bound to the sensor layer. This, in turn, explained the blue shift in SPR reflectance curves. This optical sensor offers great potential as a trustworthy solution for direct measurement due to its simple construction, high sensitivity, and other sensing features.

11.
Biomacromolecules ; 23(5): 1827-1840, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35378031

RESUMO

The tiny spider makes dragline silk fibers with unbeatable toughness, all under the most innocuous conditions. Scientists have persistently tried to emulate its natural silk spinning process using recombinant proteins with a view toward creating a new wave of smart materials, yet most efforts have fallen short of attaining the native fiber's excellent mechanical properties. One reason for these shortcomings may be that artificial spider silk systems tend to be overly simplified and may not sufficiently take into account the true complexity of the underlying protein sequences and of the multidimensional aspects of the natural self-assembly process that give rise to the hierarchically structured fibers. Here, we discuss recent findings regarding the material constituents of spider dragline silk, including novel spidroin subtypes, nonspidroin proteins, and possible involvement of post-translational modifications, which together suggest a complexity that transcends the two-component MaSp1/MaSp2 system. We subsequently consider insights into the spidroin domain functions, structures, and overall mechanisms for the rapid transition from disordered soluble protein into a highly organized fiber, including the possibility of viewing spider silk self-assembly through a framework relevant to biomolecular condensates. Finally, we consider the concept of "biomimetics" as it applies to artificial spider silk production with a focus on key practical aspects of design and evaluation that may hopefully inform efforts to more closely reproduce the remarkable structure and function of the native silk fiber using artificial methods.


Assuntos
Fibroínas , Aranhas , Sequência de Aminoácidos , Animais , Fibroínas/química , Fibroínas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Seda/química , Aranhas/metabolismo
12.
PLoS Negl Trop Dis ; 16(3): e0010092, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35333859

RESUMO

BACKGROUND: Schistosomiasis (SCH) and soil-transmitted helminthiasis (STH) are known to be endemic in Yemen. However, the distribution of both diseases had not previously been assessed by a well-structured national mapping study covering all governorates. The main aim of this study was, therefore, to map the prevalence of SCH and STH in Yemen in order to better inform implementation of effective national control and elimination interventions. The assessment of the distribution of anaemia was also included as a well-known consequence of infection with both SCH and STH. Secondarily, the study aimed to provide a broad indication of the impact of large-scale treatment on the distribution of infection. METHODOLOGY AND PRINCIPAL FINDINGS: To achive these aims, 80,432 children (10-14 years old) from 2,664 schools in 332 of Yemen's 333 districts were included, in 2014, into this national cross-sectional survey. Countrywide, 63.3% (210/332) and 75.6% (251/332) of districts were found to be endemic for SCH and STH respectively. More districts were affected by intestinal than urogenital SCH (54.2% and 31.6% respectively). SCH infection was mostly mild and moderate, with no districts reporting high infection. One quarter (24.4%) of Yemeni districts had high or moderate levels of Ascaris lumbricoides infection. Infection with Trichuris trichiura was the second most common STH (44.9% of districts infected) after A. lumbricoides (68.1%). Hookworm was the least prevalent STH (9.0%). Anaemia was prevalent in 96.4% of districts; it represented a severe public health problem (prevalence ≥ 40%) in 26.5% of districts, and a mild to moderate problem in two thirds of the districts (33.7% and 36.1% respectively). CONCLUSION: This study provided the first comprehensive mapping of SCH, STH, and anaemia across the country. This formed the basis for evaluating and continuing the national control and elimination programme for these neglected tropical diseases in Yemen.


Assuntos
Anemia , Ascaríase , Helmintíase , Helmintos , Esquistossomose Urinária , Adolescente , Anemia/epidemiologia , Animais , Ascaríase/epidemiologia , Criança , Estudos Transversais , Fezes , Helmintíase/epidemiologia , Helmintíase/prevenção & controle , Humanos , Doenças Negligenciadas/epidemiologia , Prevalência , Solo , Iêmen/epidemiologia
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 263: 120202, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34333400

RESUMO

Due to the crucial role of dopamine (DA) in health and peripheral nervous systems, it is particularly important to develop an efficient and accurate sensor to monitor and determine DA concentrations for diagnostic purposes and diseases prevention. Up to now, using surface plasmon resonance (SPR) sensors in DA determination is very limited and its application still at the primary stage. In this work, a simple and ultra-sensitive SPR sensor was constructed for DA detection by preparation of chitosan- graphene quantum dots (CS-GQDs) thin film as the sensing layer. Other SPR measurements were conducted using different sensing layers; GQDs, CS for comparison. The proposed thin films were prepared by spin coating technique. The developed CS-GQDs thin film-based SPR sensor was successfully tested in DA concentration range from 0 fM to 1 pM. The designed SPR sensor showed outstanding performance in detecting DA sensitively (S = 0.011°/fM, R2 = 0.8174) with low detection limit of 1.0 fM has been achieved for the first time. The increased angular shift of SPR dip, narrow full width half maximum of the SPR curves, excellent signal-to-noise ratio and figure of merit, and a binding affinity constant (KA) of 2.962 PM-1 demonstrated the potential of this sensor to detect DA with high accuracy. Overall, it was concluded that the proposed sensor would serve as a valuable tool in clinical diagnostic for the serious neurological disorders. This in turns has a significant socio-economic impact.


Assuntos
Quitosana , Grafite , Pontos Quânticos , Dopamina , Ressonância de Plasmônio de Superfície
14.
Sensors (Basel) ; 21(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204853

RESUMO

Insecticides are enormously important to industry requirements and market demands in agriculture. Despite their usefulness, these insecticides can pose a dangerous risk to the safety of food, environment and all living things through various mechanisms of action. Concern about the environmental impact of repeated use of insecticides has prompted many researchers to develop rapid, economical, uncomplicated and user-friendly analytical method for the detection of insecticides. In this regards, optical sensors are considered as favorable methods for insecticides analysis because of their special features including rapid detection time, low cost, easy to use and high selectivity and sensitivity. In this review, current progresses of incorporation between recognition elements and optical sensors for insecticide detection are discussed and evaluated well, by categorizing it based on insecticide chemical classes, including the range of detection and limit of detection. Additionally, this review aims to provide powerful insights to researchers for the future development of optical sensors in the detection of insecticides.


Assuntos
Inseticidas , Agricultura , Alimentos , Inseticidas/análise
15.
Bio Protoc ; 11(9): e4005, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-34124305

RESUMO

The COVID-19 pandemic requires mass screening to identify those infected for isolation and quarantine. Individually screening large populations for the novel pathogen, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is costly and requires a lot of resources. Sample pooling methods improve the efficiency of mass screening and consume less reagents by increasing the capacity of testing and reducing the number of experiments performed, and are therefore especially suitable for under-developed countries with limited resources. Here, we propose a simple, reliable pooling strategy for COVID-19 testing using clinical nasopharyngeal (NP) and/or oropharyngeal (OP) swabs. The strategy includes the pooling of 10 NP/OP swabs for extraction and subsequent testing via quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR), and may also be applied to the screening of other pathogens.

16.
Arch Med Sci ; 17(3): 752-763, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025846

RESUMO

INTRODUCTION: Replicative senescence results in dysregulation of cell proliferation and differentiation, which plays a role in the regenerative defects observed during age-related muscle atrophy. Vitamin E is a well-known antioxidant, which potentially ameliorates a wide range of age-related manifestations. The aim of this study was to determine the effects of tocotrienol-rich fraction (TRF) in modulating the expression of proliferation- and differentiation-associated proteins in senescent human myoblasts during the differentiation phase. MATERIAL AND METHODS: Human skeletal muscle myoblasts were cultured until senescence. Young and senescent cells were treated with TRF for 24 h before and after differentiation induction, followed by evaluation of cellular morphology and efficiency of differentiation. Expression of cell proliferation marker Ki67 protein and myogenic regulatory factors MyoD and myogenin were determined. RESULTS: Our findings showed that treatment with TRF significantly improved the morphology of senescent myoblasts. Promotion of differentiation was observed in young and senescent myoblasts with TRF treatment as shown by the increased fusion index and larger size of myotubes. Increased Ki67 and myogenin expression with TRF treatment was also observed in senescent myoblasts, suggesting amelioration of the myogenic program by TRF during replicative senescence. CONCLUSIONS: TRF modulates the expression of regulatory factors related to proliferation and differentiation in senescent human myoblasts and could be beneficial for ameliorating the regenerative defects during aging.

17.
Polymers (Basel) ; 13(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33671059

RESUMO

This paper proposes a novel idea to enhance the sensitivity and selectivity of surface plasmon resonance (SPR) optical sensor for detection of dengue virus type-2 envelope proteins (DENV-2 E-proteins) using polyamidoamine (PAMAM) dendrimer biopolymer-based nanocomposite thin film. For this purpose, two ranges of DENV-2 E-protein concentrations, i.e., 0.000008-0.0001 nM and 0.00008-0.005 nM were evaluated, and the lowest detectable concentration was achieved at 0.00008 nM. The incorporation of PAMAM dendrimer-based nanocomposite thin film with an SPR sensor exhibited a significant increase in sensitivity and binding affinity to a lower range DENV-2 E-protein concentrations. Moreover, the proposed sensor displayed good selectivity towards DENV-2 E-proteins and have an average recovery of 80-120%. The findings of this study demonstrated that PAMAM dendrimer-based nanocomposite thin film combined with SPR sensor is a promising diagnostic tool for sensitive and selective detection of DENV-2 E-proteins.

18.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670482

RESUMO

In this paper, the structural and optical properties of ZnO-SiO2-based ceramics fabricated from oil palm empty fruit bunch (OPEFB) were investigated. The OPEFB waste was burned at 600, 700 and 800 °C to form palm ash and was then treated with sulfuric acid to extract silica from the ash. X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses confirmed the existence of SiO2 in the sample. Field emission scanning electron microscopy (FESEM) showed that the particles displayed an irregular shape and became finer after leaching. Then, the solid-state method was used to produce the ZnO-SiO2 composite and the samples were sintered at 600, 800, 1000, 1200 and 1400 °C. The XRD peaks of the Zn2SiO4 showed high intensity, which indicated high crystallinity of the composite. FESEM images proved that the grain boundaries were larger as the temperature increased. Upon obtaining the absorbance spectrum from ultraviolet-visible (UV-Vis) spectroscopy, the energy band gaps obtained were 3.192, 3.202 and 3.214 eV at room temperature, 600 and 800 °C, respectively, and decreased to 3.127, 2.854 and 2.609 eV at 1000, 1200 and 1400 °C, respectively. OPEFB shows high potential as a silica source in producing promising optical materials.


Assuntos
Frutas/química , Óleo de Palmeira/química , Dióxido de Silício/síntese química , Óxido de Zinco/síntese química , Dióxido de Silício/química , Análise Espectral , Temperatura , Resíduos , Difração de Raios X , Óxido de Zinco/química
19.
Materials (Basel) ; 14(5)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670923

RESUMO

Arecanut husk (AH) was selected as a material for silica replacement in the synthesis process of glass-ceramics zinc silicate and also the fact that it has no traditional use and often being dumped and results in environmental issues. The process of pyrolysis was carried out at temperature 700 °C and above based on thermogravimetric analysis to produce arecanut husk ash (AHA). The average purity of the silica content in AHA ranged from 29.17% to 45.43%. Furthermore, zinc oxide was introduced to AHA and zinc silicate started to form at sintering temperature 700 °C and showed increased diffraction intensity upon higher sintering temperature of 600 °C to 1000 °C based on X-ray diffraction (XRD) analysis. The grain sizes of the zinc silicate increased from 1011 nm to 3518 nm based on the morphological studies carried out by field emission scanning electron microscopy (FESEM). In addition, the optical band gap of the sample was measured to be in the range from 2.410 eV to 2.697 eV after sintering temperature. From the data, it is believed that a cleaner production of low-cost zinc silicate can be achieved by using arecanut husk and have the potential to be used as phosphors materials.

20.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-978980

RESUMO

@#Introduction: Dental surgeon exposes to numerous occupational hazards include the bloodborne pathogens, pharmaceuticals, ergonomic hazards, noise, vibration and workplace violence. It causes prolonged health effects on short or long term exposure include musculoskeletal disorder, back pain and other health issues. This study aimed to identify the awareness level of occupational hazards and experiences among dental surgeons and to determine whether preventive measures are employed. Methods: A cross-sectional study design and convenience sampling method had been used in this study. The Occupational Hazards in Dentistry questionnaire was self-administered by 39 dental surgeons in International Islamic University Malaysia, Kuantan. The data were analysed using descriptive, chi-square and thematic analysis. Results: The overall response rate was good (78%). Among the participants, 59% were female, and 41% were male. Half of the participants (59%) had worked for 11-20 years. The majority of the participants (82%) practised a correct posture while providing dental treatment. The most-reported pain areas were at the shoulder and neck and followed by the lower back. Approximately, 10% of the participants had been diagnosed with cervical spondylitis/ degenerative cervical discs. Most participants have taken preventive measures to reduce exposure to these occupational hazards. Conclusion: Work-related pain is common among dental surgeons. The most affected pain area is the shoulder and neck, followed by back and wrist pain. Occupational hazards can be alleviated effectively using a comprehensive approach. It is essential for dentistry to incorporate comprehensive strategies into practice to improve productivity and enhance occupational safety.

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