Displaying publications 21 - 40 of 118 in total

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  1. Fulltext Impact of two-phase hybrid nanofluid approach on mixed convection inside wavy lid-driven cavity having localized solid block
    Alsabery AI, Tayebi T, Kadhim HT, Ghalambaz M, Hashim I, Chamkha AJ
    J Adv Res, 2021 May;30:63-74.
    PMID: 34026287 DOI: 10.1016/j.jare.2020.09.008
    Introduction: Mixed convection flow and heat transfer within various cavities including lid-driven walls has many engineering applications. Investigation of such a problem is important in enhancing the performance of the cooling of electric, electronic and nuclear devices and controlling the fluid flow and heat exchange of the solar thermal operations and thermal storage.

    Objectives: The main aim of this fundamental investigation is to examine the influence of a two-phase hybrid nanofluid approach on mixed convection characteristics including the consequences of varying Richardson number, number of oscillations, nanoparticle volume fraction, and dimensionless length and dimensionless position of the solid obstacle.

    Methods: The migration of composite hybrid nanoparticles due to the nano-scale forces of the Brownian motion and thermophoresis was taken into account. There is an inner block near the middle of the enclosure, which contributes toward the flow, heat, and mass transfer. The top lid cover wall of the enclosure is allowed to move which induces a mixed convection flow. The impact of the migration of hybrid nanoparticles with regard to heat transfer is also conveyed in the conservation of energy. The governing equations are molded into the non-dimensional pattern and then explained using the finite element technique. The effect of various non-dimensional parameters such as the volume fraction of nanoparticles, the wave number of walls, and the Richardson number on the heat transfer and the concentration distribution of nanoparticles are examined. Various case studies for Al2O3-Cu/water hybrid nanofluids are performed.

    Results: The results reveal that the temperature gradient could induce a notable concentration variation in the enclosure.

    Conclusion: The location of the solid block and undulation of surfaces are valuable in the control of the heat transfer and the concentration distribution of the composite nanoparticles.

    Matched MeSH terms: Electronics
  2. Fulltext Structural and Optical Characteristics of PVA:C-Dot Composites: Tuning the Absorption of Ultra Violet (UV) Region
    Aziz SB, Hassan AQ, Mohammed SJ, Karim WO, Kadir MFZ, Tajuddin HA, et al.
    Nanomaterials (Basel), 2019 Feb 06;9(2).
    PMID: 30736346 DOI: 10.3390/nano9020216
    : In this work the influence of carbon nano-dots (CNDs) on absorption of ultra violet (UV) spectra in hybrid PVA based composites was studied. The FTIR results reveal the complex formation between PVA and CNDs. The shifting was observed in XRD spectrum of PVA:CNDs composites compared to pure PVA. The Debye-Scherrer formula was used to calculate the crystallite size of CNDs and crystalline phases of pure PVA and PVA:CNDs composites. The FESEM images emphasized the presence and dispersion of C-dots on the surface of the composite samples. From the images, a strong and clear absorption was noticed in the spectra. The strong absorption that appeared peaks at 280 nm and 430 nm can be ascribed to the n-π* and π-π* transitions, respectively. The absorption edge shifted to lower photon energy sides with increasing CNDs. The luminescence behavior of PVA:CNDs composite was confirmed using digital and photo luminescence (PL) measurements. The optical dielectric constant which is related to the density of states was studied and the optical band gap was characterized accurately using optical dielectric loss parameter. The Taucs model was used to determine the type of electronic transition in the samples.
    Matched MeSH terms: Electronics
  3. E-waste recycling intention paradigm of small and medium electronics store managers in Bangladesh: An S-O-R perspective
    Mahmud I, Sultana S, Rahman A, Ramayah T, Cheng Ling T
    Waste Manag Res, 2020 Dec;38(12):1438-1449.
    PMID: 32364437 DOI: 10.1177/0734242X20914753
    Each year Bangladesh produces around 400,000 metric tonnes of e-waste. E-waste accumulation is expected to increase by 20% annually. In order to facilitate e-waste recycling, it is crucial to identify the factors. In this study, building on the stimulus-organism-response framework, we develop a research model to explore the effect of information publicity, ascription of responsibility and convenience of recycling on the recycling attitude, subjective norm, personal norm and perceived behaviour control which lead to recycling intention. Data were gathered from 127 small and medium electronics store managers. The structural equation modelling technique was used to test the paths. The result suggests a significant influence of the element of stimulus (S) on the element of organism (O). The relationship between the element of organism (O) and the element of response (R) is partial. This paper contributes to the body of work dedicated to helping us better understand the recycling behaviour from the stimulus-organism-response perspective. From the viewpoint of practice, this research sheds light on some of the challenges that the implementer might face when making strategy and policy for e-waste management in Bangladesh.
    Matched MeSH terms: Electronics
  4. Fulltext A Single Centre Annual Audit on Computed Tomography Pulmonary Angiogram: Demographic, Clinical Scoring System, Patients’ Outcome
    Low Qin Jian, Teo Kuo Zhau, Mohd Nadzri Misni, Cheo Seng Wee
    Borneo Journal of Medical Sciences, 2020;14(2):11-18.
    MyJurnal
    Computed tomography pulmonary angiogram (CTPA) is widely used in the investigation of suspected pulmonary embolism. CTPA is not without adverse effects as it involves intravenous contrast injection and radiation exposure. The annual incidence of pulmonary embolism is 60 – 70 per 100,000 populations and CTPA remains the commonest imaging modality1. This study aims to audit all CTPA performed at Hospital Sultanah Nora Ismail, Batu Pahat, Johor for the entire year of 2018 to illustrate the demographic data, symptoms, risk factors, clinical scoring system applied and patients’ outcome. A retrospective study was conducted to audit all CTPA performed between 1st January to 31st December 2018 via the radiology department electronic records and patients’ records. There were a total of 60 CTPA performed in the entire year of 2018 with 16 positive and 44 negative scans. Among the 16 positive scans, 7 (44%) had a Wells score above 6, 6 (38%) had a Wells score between 2 – 6 and 3 (18%) had a Wells score less than 2. Out of the 16 positive scans, 4 (25%) were known malignancy and 1 was a known case of anti-phospholipid syndrome. All 60 patients had electrographs and arterial blood gases performed prior to CTPA. D dimer was performed in 15 cases (5%). Among the 16 positive scan patients, 4 (25%) passed away during the same admission directly or indirectly related to pulmonary embolism. This annual computed tomography audit report will assist clinicians in making better diagnostic decision when dealing with patients with suspected pulmonary embolism.
    Matched MeSH terms: Electronics
  5. Fulltext An Improved Fabrication Technique for the 3-D Frequency Selective Surface based on Water Transfer Printing Technology
    Harnois M, Himdi M, Yong WY, Rahim SKA, Tekkouk K, Cheval N
    Sci Rep, 2020 Feb 03;10(1):1714.
    PMID: 32015444 DOI: 10.1038/s41598-020-58657-5
    Manufacturing an array of high-quality metallic pattern layers on a dielectric substrate remains a major challenge in the development of flexible and 3-D frequency selective surfaces (FSS). This paper proposes an improved fabrication solution for the 3-D FSS based on water transfer printing (WTP) technology. The main advantages of the proposed solution are its ability to transform complicated 2-D planar FSS patterns into 3-D structures while improving both manufacturing quality and production costs. WTP technology makes use of water surface tension to keep the thin metallic patterns of the proposed FSS floating flat with the absence of a solid planar substrate. This feature enables these metallic FSS patterns to be transferred onto 3-D structures through a dipping process. To test the effectiveness of the proposed technique, the FSS was designed using computer simulation software Microwave Studio to obtain the numerical performance of the FSS structure. The WTP technology was then used to fabricate the proposed FSS prototype before its performance was tested experimentally. The measurement results agreed well with the numerical results, indicating the proposed manufacturing solution would support the development of complicated 3-D electronics devices, such as conformal antenna arrays and metamaterials.
    Matched MeSH terms: Electronics
  6. Development of a control system for artificially rehabilitated limbs: a review
    Bhuiyan MS, Choudhury IA, Dahari M
    Biol Cybern, 2015 Apr;109(2):141-62.
    PMID: 25491411 DOI: 10.1007/s00422-014-0635-1
    Development of an advanced control system for prostheses (artificial limbs) is necessary to provide functionality, effectiveness, and preferably the feeling of a sound living limb. The development of the control system has introduced varieties of control strategies depending on the application. This paper reviews some control systems used for prosthetics, orthotics, and exoskeletons. The advantages and limitations of different control systems for particular applications have been discussed and presented in a comparative manner to help in deciding the appropriate method for pertinent application.
    Matched MeSH terms: Electronics, Medical
  7. Dual-response quadratic model for optimisation of electricity generation and chlorophenol degradation by electro-degradative Bacillus subtilis in microbial fuel cell system
    Hassan H, Jin B, Dai S
    Environ Technol, 2021 Apr 01.
    PMID: 33749543 DOI: 10.1080/09593330.2021.1907451
    The interactions within microbial, chemical and electronic elements in microbial fuel cell (MFC) system can be crucial for its bio-electrochemical activities and overall performance. Therefore, this study explored polynomial models by response surface methodology (RSM) to better understand interactions among anode pH, cathode pH and inoculum size for optimising MFC system for generation of electricity and degradation of 2,4-dichlorophenol. A statistical central composite design by RSM was used to develop the quadratic model designs. The optimised parameters were determined and evaluated by statistical results and the best MFC systematic outcomes in terms of current generation and chlorophenol degradation. Statistical results revealed that the optimum current density of 106 mA/m2 could be achieved at anode pH 7.5, cathode pH 6.3-6.6 and 21-28% for inoculum size. Anode-cathode pHs interaction was found to positively influence the current generation through extracellular electron transfer mechanism. The phenolic degradation was found to have lower response using these three parameter interactions. Only inoculum size-cathode pH interaction appeared to be significant where the optimum predicted phenolic degradation could be attained at pH 7.6 for cathode pH and 29.6% for inoculum size.
    Matched MeSH terms: Electronics
  8. Fulltext Design of a MEMS-Based Oscillator Using 180nm CMOS Technology
    Roy S, Ramiah H, Reza AW, Lim CC, Ferrer EM
    PLoS One, 2016;11(7):e0158954.
    PMID: 27391136 DOI: 10.1371/journal.pone.0158954
    Micro-electro mechanical system (MEMS) based oscillators are revolutionizing the timing industry as a cost effective solution, enhanced with more features, superior performance and better reliability. The design of a sustaining amplifier was triggered primarily to replenish MEMS resonator's high motion losses due to the possibility of their 'system-on-chip' integrated circuit solution. The design of a sustaining amplifier observing high gain and adequate phase shift for an electrostatic clamp-clamp (C-C) beam MEMS resonator, involves the use of an 180nm CMOS process with an unloaded Q of 1000 in realizing a fixed frequency oscillator. A net 122dBΩ transimpedance gain with adequate phase shift has ensured 17.22MHz resonant frequency oscillation with a layout area consumption of 0.121 mm2 in the integrated chip solution, the sustaining amplifier draws 6.3mW with a respective phase noise of -84dBc/Hz at 1kHz offset is achieved within a noise floor of -103dBC/Hz. In this work, a comparison is drawn among similar design studies on the basis of a defined figure of merit (FOM). A low phase noise of 1kHz, high figure of merit and the smaller size of the chip has accredited to the design's applicability towards in the implementation of a clock generative integrated circuit. In addition to that, this complete silicon based MEMS oscillator in a monolithic solution has offered a cost effective solution for industrial or biomedical electronic applications.
    Matched MeSH terms: Electronics, Medical*
  9. Fulltext A biomimetic sensor for the classification of honeys of different floral origin and the detection of adulteration
    Zakaria A, Shakaff AY, Masnan MJ, Ahmad MN, Adom AH, Jaafar MN, et al.
    Sensors (Basel), 2011;11(8):7799-822.
    PMID: 22164046 DOI: 10.3390/s110807799
    The major compounds in honey are carbohydrates such as monosaccharides and disaccharides. The same compounds are found in cane-sugar concentrates. Unfortunately when sugar concentrate is added to honey, laboratory assessments are found to be ineffective in detecting this adulteration. Unlike tracing heavy metals in honey, sugar adulterated honey is much trickier and harder to detect, and traditionally it has been very challenging to come up with a suitable method to prove the presence of adulterants in honey products. This paper proposes a combination of array sensing and multi-modality sensor fusion that can effectively discriminate the samples not only based on the compounds present in the sample but also mimic the way humans perceive flavours and aromas. Conversely, analytical instruments are based on chemical separations which may alter the properties of the volatiles or flavours of a particular honey. The present work is focused on classifying 18 samples of different honeys, sugar syrups and adulterated samples using data fusion of electronic nose (e-nose) and electronic tongue (e-tongue) measurements. Each group of samples was evaluated separately by the e-nose and e-tongue. Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were able to separately discriminate monofloral honey from sugar syrup, and polyfloral honey from sugar and adulterated samples using the e-nose and e-tongue. The e-nose was observed to give better separation compared to e-tongue assessment, particularly when LDA was applied. However, when all samples were combined in one classification analysis, neither PCA nor LDA were able to discriminate between honeys of different floral origins, sugar syrup and adulterated samples. By applying a sensor fusion technique, the classification for the 18 different samples was improved. Significant improvement was observed using PCA, while LDA not only improved the discrimination but also gave better classification. An improvement in performance was also observed using a Probabilistic Neural Network classifier when the e-nose and e-tongue data were fused.
    Matched MeSH terms: Electronics
  10. Chitin nanocrystals based complex fluids: A green nanotechnology
    Kumar S, Foroozesh J
    Carbohydr Polym, 2021 Apr 01;257:117619.
    PMID: 33541647 DOI: 10.1016/j.carbpol.2021.117619
    Chitin biopolymer has received significant attention recently by many industries as a green technology. Nanotechnology has been used to make chitin nanocrystals (ChiNCs) that are rod-shaped natural nanomaterials with nanoscale size. Owing to the unique features such as biodegradability, biocompatibility, renewability, rod-shape, and excellent surface and interfacial, physiochemical, and thermo-mechanical properties; ChiNCs have been green and attractive products with wide applications specifically in medical and pharmaceutical, food and packaging, cosmetic, electrical, and electronic, and also in the oil and gas industry. This review aims to give a comprehensive and applied insight into ChiNCs technology. It starts with reviewing different sources of chitin and their extraction methods followed by the characterization of ChiNCs. Furthermore, a detailed investigation into various complex fluids (dispersions, emulsions, foams, and gels) stabilized by ChiNCs and their characterisation have been thoroughly deliberated. Finally, the current status including ground-breaking applications, untapped investigations, and future prospective have been presented.
    Matched MeSH terms: Electronics
  11. The prevalence and risk factors of canine demodicosis: A retrospective long-term study of 409 cases
    Shchelkanov MY, Tabakaeva Moskvina TV, Kim EM, Derunov DA, Galkina IV
    Trop Biomed, 2020 Sep 01;37(3):778-782.
    PMID: 33612790 DOI: 10.47665/tb.37.3.778
    Canine demodicosis is a common skin disorder with multiple risk factors, including age and breed predisposition. There is relatively limited information about the risk factors for canine demodicosis in large canine populations. This retrospective case-control study was conducted by searching the electronic records of dogs with skin lesions for the presence of Demodex mites in skin scrapings. Diagnosis of demodicosis was based on the presence of skin lesions and mites in skin scrapings. Multivariate analysis was conducted using logistic regression analysis to estimate the relative risk and odds ratio of variables hypothesized to influence the risk of canine demodicosis, such as age, sex, breed, season, and parasitic infection. The results of multivariate logistic regression analysis showed a positive correlation between the dogs' age and demodicosis. Dogs older than three years, as well as puppies, had a high risk of demodicosis (P0.05). Breeds with the greatest association (odds ratio) with demodicosis included the American Staffordshire Terrier (OR=0.9) and Moscow Watchdog (OR=0.2). The presence of intestinal parasites, such as Diphyllobothrium latum, was significantly associated with demodicosis.
    Matched MeSH terms: Electronics
  12. Fulltext Synthesis mechanism of low-voltage praseodymium oxide doped zinc oxide varistor ceramics prepared through modified citrate gel coating
    Abdullah WR, Zakaria A, Ghazali MS
    Int J Mol Sci, 2012;13(4):5278-89.
    PMID: 22606043 DOI: 10.3390/ijms13045278
    High demands on low-voltage electronics have increased the need for zinc oxide (ZnO) varistors with fast response, highly non-linear current-voltage characteristics and energy absorption capabilities at low breakdown voltage. However, trade-off between breakdown voltage and grain size poses a critical bottle-neck in the production of low-voltage varistors. The present study highlights the synthesis mechanism for obtaining praseodymium oxide (Pr(6)O(11)) based ZnO varistor ceramics having breakdown voltages of 2.8 to 13.3 V/mm through employment of direct modified citrate gel coating technique. Precursor powder and its ceramics were examined by means of TG/DTG, FTIR, XRD and FESEM analyses. The electrical properties as a function of Pr(6)O(11) addition were analyzed on the basis of I-V characteristic measurement. The breakdown voltage could be adjusted from 0.01 to 0.06 V per grain boundary by controlling the amount of Pr(6)O(11) from 0.2 to 0.8 mol%, without alteration of the grain size. The non-linearity coefficient, α, varied from 3.0 to 3.5 and the barrier height ranged from 0.56 to 0.64 eV. Breakdown voltage and α lowering with increasing Pr(6)O(11) content were associated to reduction in the barrier height caused by variation in O vacancies at grain boundary.
    Matched MeSH terms: Electronics, Medical/instrumentation*
  13. Simulated electronic health documentation: A cross-sectional exploration of factors influencing nursing students' intention to use
    Chan KG, Pawi S, Ong MF, Kowitlawakul Y, Goy SC
    Nurse Educ Pract, 2020 Oct;48:102864.
    PMID: 32920369 DOI: 10.1016/j.nepr.2020.102864
    The aim of this study was to investigate factors influencing nursing students' intention to use a simulated web-application 'Integrated Nursing Education System' for practicing electronic health documentation. The cross-sectional study was conducted at a Malaysian University that provides undergraduate nursing degree program. A total of 133 undergraduate nursing students in their year 2 to year 4 of the program were recruited. They had accessed the simulated web-application as part of the teaching-learning activities during the academic year 2016/2017. Technology Acceptance Model was used to guide the study. Validated questionnaires were used to measure the students' perceived ease of use, perceived usefulness, attitudes and intention to use the application. Data collection was done at the end of the semester. Data analysis was done using SPSS (19.0) and AMOS (23.0). Perceived usefulness was the most influential factor of the students' intention to use the simulated web-application. Perceived ease of use influenced their perceived usefulness significantly. Nurse educators should explain the usefulness of the simulated web-application before assigning students to access it to practice electronic health documentation. The availability of a stable internet access and IT support is important to influence students' perceived ease of use and intention to use the application.
    Matched MeSH terms: Electronics
  14. Nicotine dependence and associated factors among persons who use electronic e-cigarettes in Malaysia - an online survey
    Sreeramareddy CT, Shroff SM, Gunjal S
    Subst Abuse Treat Prev Policy, 2023 Aug 29;18(1):51.
    PMID: 37644524 DOI: 10.1186/s13011-023-00558-7
    BACKGROUND: Nicotine dependence, factors associated with dependence, and self-reported side effects among people who use e-cigarettes are scarce in developing countries.

    METHODS: A sample of 302 persons who currently use e-cigarettes was recruited from discussion forums on Reddit, Facebook, and the forum 'lowyat'. The online Google form survey collected data on demographics, e-cigarette use, and the reasons, for cigarette smoking, Fagerstorm Test for Nicotine Dependence adapted for e-cigarettes (eFTND), and side effects experienced.

    RESULTS: The mean age was 25.5 years (6.5), 60.6% were males and 86% had higher education. About 47% were using e-cigarettes only, 27.8% were currently using dual products (both electronic and conventional cigarettes), and 25.2% had also smoked cigarettes in the past. 'Less harmful than cigarettes' (56.3%), 'because I enjoy it' (46.7%), and 'it has a variety of flavors (40.4%) were the common reasons for e-cigarette use. The mean eFTND score was 3.9 (SD = 2.2), with a median of four side effects (IQR 3-6), sore or dry mouth/throat (41.4%), cough 33.4%, headache (20.5%), dizziness (16.2%) were commonly reported side effects. eFTND score and side effects were higher among persons using dual products. By multiple linear regression analysis, males (β = 0.56 95% CI 0.45, 1.05, p = 0.033), dual-use (β = 0.95 95% CI 0.34, 1.56, p 

    Matched MeSH terms: Electronics
  15. A review of sustainable e-waste generation and management: Present and future perspectives
    Ismail H, Hanafiah MM
    J Environ Manage, 2020 Jun 15;264:110495.
    PMID: 32250915 DOI: 10.1016/j.jenvman.2020.110495
    Studies on sustainable management of waste from electrical and electronic equipment (or e-waste) have gained increasing attention from researchers around the world in recent years, with investigations into various aspects of e-waste management were investigated. Studies on e-waste generation by previous papers have been reviewed to provide an overview of the current research progress and recommendations for future research. The relevant existing studies were collected from various databases. Using content analysis, three main aspects of the existing studies were evaluated: the distribution and trends of the publications, the scope and boundaries of the studies, and the current research practices and research applications. Although there was a significant increasing trend of the amount of research on the evaluation of e-waste generation, however, the number of publications based on the countries of origin was still small. Another limitation was found related to the differences in the selection of research subjects and the level of analysis resulted in variations in the scopes and boundaries of the existing studies. Various other research areas were investigated further based on their research findings, but the analysis of various methodological aspects was complicated due to the increasing number of newly developed methodologies and the lack of comprehensive and up-to-date reviews on this research area. Additionally, there was also a need to evaluate emerging and/or older technology, which led electrical appliances to be overlooked. We found that comprehensive and up-to-date reviews of the methodological aspects of e-waste generation are still lacking. Based on the research gaps and limitations discussed, recommendations for future research were made.
    Matched MeSH terms: Electronics
  16. Preadmission use of inhaled corticosteroids and risk of fatal or severe COVID-19: a meta-analysis
    Kow CS, Hasan SS
    J Asthma, 2021 Feb 08.
    PMID: 33461348 DOI: 10.1080/02770903.2021.1878531
    Objective: With emerging of observational evidence, we aimed to perform a meta-analysis to summarize the overall effect of the chronic use of inhaled corticosteroids on the clinical outcomes in patients with coronavirus disease 2019 (COVID-19). Methods:Systematic literature search in electronic databases was performed to identify observational studies that investigated the preadmission use of inhaled corticosteroids on the risk of a fatal or severe course of illness in patients with COVID-19 and reported adjusted measures of association. Adjusted odds ratios or relative risks and the corresponding 95% confidence intervals from each study were pooled to produce pooled odds ratio and 95% confidence interval. Results: The meta-analysis revealed no significant difference in the risk for the development of a fatal course of COVID-19 with preadmission use of inhaled corticosteroids in patients with COVID-19 relative to non-use of inhaled corticosteroids (pooled odds ratio=1.28; 95% confidence interval 0.73-2.26). Similarly, the meta-analysis observed no significant difference in the risk for the development of a severe course of COVID-19 with preadmission use of inhaled corticosteroids in patients with COVID-19 relative to non-use of inhaled corticosteroids (pooled odds ratio=1.45; 95% confidence interval 0.96-2.20).Conclusions: Our findings assured the safety of continued use of inhaled corticosteroids during the COVID-19 pandemic.
    Matched MeSH terms: Electronics
  17. Fulltext Soldering Characteristics and Mechanical Properties of Sn-1.0Ag-0.5Cu Solder with Minor Aluminum Addition
    Leong YM, Haseeb ASMA
    Materials (Basel), 2016 Jun 28;9(7).
    PMID: 28773645 DOI: 10.3390/ma9070522
    Driven by the trends towards miniaturization in lead free electronic products, researchers are putting immense efforts to improve the properties and reliabilities of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC105 (Sn-1.0Ag-0.5Cu) because of economic reasons and improvement of impact resistance as compared to SAC305 (Sn-3.0Ag-0.5Cu. The present work investigates the effect of minor aluminum (Al) addition (0.1-0.5 wt.%) to SAC105 on the interfacial structure between solder and copper substrate during reflow. The addition of minor Al promoted formation of small, equiaxed Cu-Al particle, which are identified as Cu₃Al₂. Cu₃Al₂ resided at the near surface/edges of the solder and exhibited higher hardness and modulus. Results show that the minor addition of Al does not alter the morphology of the interfacial intermetallic compounds, but they substantially suppress the growth of the interfacial Cu₆Sn₅ intermetallic compound (IMC) after reflow. During isothermal aging, minor alloying Al has reduced the thickness of interfacial Cu₆Sn₅ IMC but has no significant effect on the thickness of Cu₃Sn. It is suggested that of atoms of Al exert their influence by hindering the flow of reacting species at the interface.
    Matched MeSH terms: Electronics
  18. Fulltext A Survey on Daily Activity Inclination and Health Complaints among Urban Youth in Malaysia
    Chen AH, Rosli SA, Hovis JK
    J Environ Public Health, 2020;2020:9793425.
    PMID: 33376494 DOI: 10.1155/2020/9793425
    Environmental influence is one of the attributing factors for health status. Chronic interaction with electronic display technology and lack of outdoor activities might lead to health issues. Given the concerns about the digital impact on lifestyle and health challenges, we aimed to investigate the daily activity inclination and health complaints among the Malaysian youth. A self-administered questionnaire covering lifestyle and health challenges was completed by 220 youths aged between 16 and 25. There were a total of 22 questions. Seven questions inspected the patterns of indoor and outdoor activities. Fifteen questions focused on the visual and musculoskeletal symptoms linked to both mental and physical health. The total time spent indoors (15.0 ± 5.4 hours/day) was significantly higher than that spent outdoors (2.5 ± 2.6 hours/day) (t = 39.01, p < 0.05). Total time engrossed in sedentary activities (13.0 ± 4.5 hours/day) was significantly higher than that in nonsedentary activities (4.5 ± 3.8 hours/day) comprised of indoor sports and any outdoor engagements (t = 27.10, p < 0.05). The total time spent on electronic related activities (9.5 ± 3.7 hours/day) was were higher than time spent on printed materials (3.4 ± 1.6 hours/day) (t = 26.01, p < 0.05). The association of sedentary activities was positive in relation to tired eyes (χ2 = 17.58, p < 0.05), sensitivity to bright light (χ2 = 12.10, p < 0.05), and neck pain (χ2 = 17.27, p < 0.05) but negative in relation to lower back pain (χ2 = 8.81, p < 0.05). Our youth spent more time in building and engaged in sedentary activities, predominantly electronic usage. The health-related symptoms, both visual and musculoskeletal symptoms, displayed a positive association with a sedentary lifestyle and a negative association with in-building time.
    Matched MeSH terms: Electronics
  19. Materials and Techniques for Implantable Nutrient Sensing Using Flexible Sensors Integrated with Metal-Organic Frameworks
    Ling W, Liew G, Li Y, Hao Y, Pan H, Wang H, et al.
    Adv Mater, 2018 Jun;30(23):e1800917.
    PMID: 29633379 DOI: 10.1002/adma.201800917
    The combination of novel materials with flexible electronic technology may yield new concepts of flexible electronic devices that effectively detect various biological chemicals to facilitate understanding of biological processes and conduct health monitoring. This paper demonstrates single- or multichannel implantable flexible sensors that are surface modified with conductive metal-organic frameworks (MOFs) such as copper-MOF and cobalt-MOF with large surface area, high porosity, and tunable catalysis capability. The sensors can monitor important nutriments such as ascorbicacid, glycine, l-tryptophan (l-Trp), and glucose with detection resolutions of 14.97, 0.71, 4.14, and 54.60 × 10-6 m, respectively. In addition, they offer sensing capability even under extreme deformation and complex surrounding environment with continuous monitoring capability for 20 d due to minimized use of biological active chemicals. Experiments using live cells and animals indicate that the MOF-modified sensors are biologically safe to cells, and can detect l-Trp in blood and interstitial fluid. This work represents the first effort in integrating MOFs with flexible sensors to achieve highly specific and sensitive implantable electrochemical detection and may inspire appearance of more flexible electronic devices with enhanced capability in sensing, energy storage, and catalysis using various properties of MOFs.
    Matched MeSH terms: Electronics
  20. Fulltext Automatic frequency controller for power amplifiers used in bio-implanted applications: issues and challenges
    Hannan MA, Hussein HA, Mutashar S, Samad SA, Hussain A
    Sensors (Basel), 2014;14(12):23843-70.
    PMID: 25615728 DOI: 10.3390/s141223843
    With the development of communication technologies, the use of wireless systems in biomedical implanted devices has become very useful. Bio-implantable devices are electronic devices which are used for treatment and monitoring brain implants, pacemakers, cochlear implants, retinal implants and so on. The inductive coupling link is used to transmit power and data between the primary and secondary sides of the biomedical implanted system, in which efficient power amplifier is very much needed to ensure the best data transmission rates and low power losses. However, the efficiency of the implanted devices depends on the circuit design, controller, load variation, changes of radio frequency coil's mutual displacement and coupling coefficients. This paper provides a comprehensive survey on various power amplifier classes and their characteristics, efficiency and controller techniques that have been used in bio-implants. The automatic frequency controller used in biomedical implants such as gate drive switching control, closed loop power control, voltage controlled oscillator, capacitor control and microcontroller frequency control have been explained. Most of these techniques keep the resonance frequency stable in transcutaneous power transfer between the external coil and the coil implanted inside the body. Detailed information including carrier frequency, power efficiency, coils displacement, power consumption, supplied voltage and CMOS chip for the controllers techniques are investigated and summarized in the provided tables. From the rigorous review, it is observed that the existing automatic frequency controller technologies are more or less can capable of performing well in the implant devices; however, the systems are still not up to the mark. Accordingly, current challenges and problems of the typical automatic frequency controller techniques for power amplifiers are illustrated, with a brief suggestions and discussion section concerning the progress of implanted device research in the future. This review will hopefully lead to increasing efforts towards the development of low powered, highly efficient, high data rate and reliable automatic frequency controllers for implanted devices.
    Matched MeSH terms: Electronics, Medical/methods*
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