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  1. Nurnazahiah A, Shahril MR, Nor Syamimi Z, Ahmad A, Sulaiman S, Lua PL
    Health Qual Life Outcomes, 2020 Jul 10;18(1):222.
    PMID: 32650777 DOI: 10.1186/s12955-020-01478-x
    BACKGROUND: Lack of physical activity throughout one's lifetime has been associated with obesity and it is also an important risk factor of breast cancer. This study aimed to determine the relationship between objectively measured physical activity and sedentary behaviour with health-related quality of life (HRQoL) among breast cancer survivors in the East Coast region of Peninsular Malaysia.

    METHODS: A cross-sectional study involving 83 breast cancer survivors was carried out in two main government referral hospitals in the region. Participants wore the ActivPAL3™ microdevice physical activity monitor for seven consecutive days. The validated European Organization for Research and Treatment of Cancer Quality of Life Questionnaires (EORTC QLQ-C30) and Breast Cancer Supplementary Measure (EORTC QLQ-BR23) were used to measure their HRQoL. Multiple linear regression analysis was conducted to determine the relationship between objectively measured physical activity and sedentary behaviour with HRQoL.

    RESULTS: Longer time spent on moderate to vigorous physical activity (MVPA) was significantly associated with an improvement of HRQoL (p = 0.039) whereas longer time spent on sedentary behaviour significantly reduced the functioning score (p = 0.005). In addition, prolonged sedentary bouts were also significantly associated with better body image that led to improved HRQoL (p = 0.013).

    CONCLUSIONS: The study findings suggest that an increase in the time spent on MVPA was associated with improved HRQoL while sedentary behaviour was associated with poorer HRQoL among breast cancer survivors. Thus, it is essential to displace sedentary behaviour with MVPA to improve the quality of life of breast cancer survivors.

  2. Rahumatullah A, Ahmad A, Noordin R, Lai JY, Baharudeen Z, Lim TS
    Exp Parasitol, 2020 Dec;219:108029.
    PMID: 33096112 DOI: 10.1016/j.exppara.2020.108029
    Echinococcus granulosus is a worldwide zoonotic infection that causes human cystic echinococcosis (CE) or hydatid disease. The present study describes the isolation and production of a monoclonal antibody against recombinant AgB protein using the developed Human AntibodY Disease ENhanced (HAYDEN)-Filariasis library. The DNA sequences of the isolated clones were analyzed, followed by gene analysis and binding assays. Clone E1 showed a full-length sequence and represents the IgHV5-LV3 antibody gene family. The antibody protein yield was satisfactory, and it reacted specifically against rAgB. The novel E1 protein is potentially useful for the development of an antigen detection assay for CE. The ability of the Brugia malayi immune antibody library to isolate antibodies against Echinococcus granulosus antigens highlights the broad coverage of immune antibody libraries.
  3. Ismail MA, Ahmad A, Mohammad JA, Fakri NMRM, Nor MZM, Pa MNM
    BMC Med Educ, 2019 Jun 25;19(1):230.
    PMID: 31238926 DOI: 10.1186/s12909-019-1658-z
    BACKGROUND: Gamification is an increasingly common phenomenon in education. It is a technique to facilitate formative assessment and to promote student learning. It has been shown to be more effective than traditional methods. This phenomenological study was conducted to explore the advantages of gamification through the use of the Kahoot! platform for formative assessment in medical education.

    METHODS: This study employed a phenomenological design. Five focus groups were conducted with medical students who had participated in several Kahoot! sessions.

    RESULTS: Thirty-six categories and nine sub-themes emerged from the focus group discussions. They were grouped into three themes: attractive learning tool, learning guidance and source of motivation.

    CONCLUSIONS: The results suggest that Kahoot! sessions motivate students to study, to determine the subject matter that needs to be studied and to be aware of what they have learned. Thus, the platform is a promising tool for formative assessment in medical education.

  4. Ahmad A, Bahri Yusoff MS, Zahiruddin Wan Mohammad WM, Mat Nor MZ
    J Taibah Univ Med Sci, 2018 Apr;13(2):113-122.
    PMID: 31435313 DOI: 10.1016/j.jtumed.2017.12.001
    Objectives: Community-based education (CBE) has an impact on the types of medical students produced at the end of medical training. However, its impact on professional identity development (PID) has not been clearly understood. This study thus explores the effect of the CBE program on PID.

    Methods: A qualitative phenomenological study was conducted on a group of Universiti Sains Malaysia medical students who had finished the Community and Family Case Study (CFCS) program. Data were gathered through focused group discussions and student reflective journals. Participants were sampled using the maximal variation technique of purposive sampling. Three steps of thematic analysis using the Atlasti software were employed to identify categories, subthemes, and themes.

    Results: Personal, role, social, and research identities were generated that contribute to the PID of medical students through the CFCS program. The results indicate that the CFCS program nurtured personal identity through the development of professional skills, soft skills, and personal values. Pertaining to role identity, this is related to patient care in terms of primary care and interprofessional awareness. Pertaining to social identity, the obvious feature was community awareness related to culture, society, and politics. A positive outcome of the CFCS program was found to be its fostering of research skills, which is related to the use of epidemiology and research methods.

    Conclusion: The findings indicate that the CFCS program promotes PID among medical students. The current data highlight and provide insights into the importance of integrating CBE into medical curricula to prepare future doctors for their entry into the profession.

  5. Mohamad N, Abdul Khanan MF, Ahmad A, Md Din AH, Shahabi H
    Sensors (Basel), 2019 Aug 31;19(17).
    PMID: 31480412 DOI: 10.3390/s19173778
    Evaluating water level changes at intertidal zones is complicated because of dynamic tidal inundation. However, water level changes during different tidal phases could be evaluated using a digital surface model (DSM) captured by unmanned aerial vehicle (UAV) with higher vertical accuracy provided by a Global Navigation Satellite System (GNSS). Image acquisition using a multirotor UAV and vertical data collection from GNSS survey were conducted at Kilim River, Langkawi Island, Kedah, Malaysia during two different tidal phases, at high and low tides. Using the Structure from Motion (SFM) algorithm, a DSM and orthomosaics were produced as the main sources of data analysis. GNSS provided horizontal and vertical geo-referencing for both the DSM and orthomosaics during post-processing after field observation at the study area. The DSM vertical accuracy against the tidal data from a tide gauge was about 12.6 cm (0.126 m) for high tide and 34.5 cm (0.345 m) for low tide. Hence, the vertical accuracy of the DSM height is still within a tolerance of ±0.5 m (with GNSS positioning data). These results open new opportunities to explore more validation methods for water level changes using various aerial platforms besides Light Detection and Ranging (LiDAR) and tidal data in the future.
  6. Alzoubi MM, Hayati KS, Rosliza AM, Ahmad AA, Al-Hamdan ZM
    Risk Manag Healthc Policy, 2019;12:167-177.
    PMID: 31576185 DOI: 10.2147/RMHP.S197038
    Background: Synergistic integration of predictors and elements that determine the success of total quality management (TQM) implementations in hospitals has been the bane of theoretical development in the TQM research area. Thus, this paper aims to offer a systematic literature review to provide a foundation on which research on TQM can be built and to identify the predictors of successful TQM in the health-care context.

    Materials and methods: A systematic literature survey was adopted in this paper, involving the review of 25 relevant researched articles found in the databases Science Direct, EBSCO, MEDLINE, CINAHL and PubMed.

    Result: The systematic literature survey reveals five variables to be core predictors of TQM, signifying how important these variables are in the successful implementation of TQM in the health-care context. Also, it is revealed that the identified core predictors have positive effects on an improved health-care system. However, the systematic survey of the literature reveals a dearth of studies on TQM in the health-care context.

    Conclusion: As TQM has become an important management approach for advancing effectiveness in the health-care sector, this kind of research is of value to researchers and managers. Stakeholders in the health sectors should introduce and implement TQM in hospitals and clinics. Nevertheless, this study has limitations, including that the databases and search engines adopted for the literature search are not exhaustive.

  7. Whba R, Su'ait MS, Tian Khoon L, Ibrahim S, Mohamed NS, Ahmad A
    Polymers (Basel), 2021 Feb 23;13(4).
    PMID: 33672185 DOI: 10.3390/polym13040660
    The exploitation of epoxidized natural rubber (ENR) in electrochemical applications is approaching its limits because of its poor thermo-mechanical properties. These properties could be improved by chemical and/or physical modification, including grafting and/or crosslinking techniques. In this work, acrylonitrile (ACN) has been successfully grafted onto ENR- 25 by a radical photopolymerization technique. The effect of (ACN to ENR) mole ratios on chemical structure and interaction, thermo-mechanical behaviour and that related to the viscoelastic properties of the polymer was investigated. The existence of the -C≡N functional group at the end-product of ACN-g-ENR is confirmed by infrared (FT-IR) and nuclear magnetic resonance (NMR) analyses. An enhanced grafting efficiency (~57%) was obtained after ACN was grafted onto the isoprene unit of ENR- 25 and showing a significant improvement in thermal stability and dielectric properties. The viscoelastic behaviour of the sample analysis showed an increase of storage modulus up to 150 × 103 MPa and the temperature of glass transition (Tg) was between -40 and 10 °C. The loss modulus, relaxation process, and tan delta were also described. Overall, the ACN-g-ENR shows a distinctive improvement in characteristics compared to ENR and can be widely used in many applications where natural rubber is used but improved thermal and mechanical properties are required. Likewise, it may also be used in electronic applications, for example, as a polymer electrolyte in batteries or supercapacitor.
  8. Ahmad A, Ramasamy K, Jaafar SM, Majeed AB, Mani V
    Food Chem Toxicol, 2014 Mar;65:120-8.
    PMID: 24373829 DOI: 10.1016/j.fct.2013.12.025
    The present study was undertaken to compare the neuroprotective effects between total isoflavones from soybean and tempeh against scopolamine-induced cognitive dysfunction. Total isoflavones (10, 20 and 40mg/kg) from soybean (SI) and tempeh (TI) were administered orally to different groups of rats (n=6) for 15days. Piracetam (400mg/kg, p.o.) was used as a standard drug while scopolamine (1mg/kg, i.p.) was used to induce amnesia in the animals. Radial arm and elevated plus mazes served as exteroceptive behavioural models to measure memory. Brain cholinergic activities (acetylcholine and acetylcholinesterase) and neuroinflammatory activities (COX-1, COX-2, IL-1β and IL10) were also assessed. Treatment with SI and TI significantly reversed the scopolamine effect and improved memory with TI group at 40mg/kg, p.o. exhibiting the best improvement (p<0.001) in rats. The TI (10, 20 and 40mg/kg, p.o.) significantly increased (p<0.001) acetylcholine and reduced acetylcholinesterase levels. Meanwhile, only a high dose (40mg/kg, p.o.) of SI showed significant improvement (p<0.05) in the cholinergic activities. Neuroinflammation study also showed that TI (40mg/kg, p.o.) was able to reduce inflammation better than SI. The TI ameliorates scopolamine-induced memory in rats through the cholinergic neuronal pathway and by prevention of neuroinflammation.
  9. Mani V, Ramasamy K, Ahmad A, Parle M, Shah SA, Majeed AB
    Food Chem Toxicol, 2012 Mar;50(3-4):1036-44.
    PMID: 22142688 DOI: 10.1016/j.fct.2011.11.037
    Dementia is a syndrome of gradual onset and continuous decline of higher cognitive functioning. It is a common disorder in older persons and has become more prevalent today. The fresh leaves of Murraya koenigii are often added to various dishes in Asian countries due to the delicious taste and flavor that they impart. These leaves have also been proven to have health benefits. In the present study, the effect of total alkaloidal extract from M. koenigii leaves (MKA) on cognitive functions and brain cholinesterase activity in mice were determined. In vitro β-secretase 1 (BACE1) inhibitory activity was also evaluated. The total alkaloidal extract was administered orally in three doses (10, 20 and 30 mg/kg) for 15 days to different groups of young and aged mice. Elevated plus maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam-, scopolamine-, and ageing-induced amnesia served as the interoceptive behavioral models. MKA (20 and 30 mg/kg, p.o.) showed significant improvement in memory scores of young and aged mice. Furthermore, the same doses of MKA reversed the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Interestingly, the brain cholinesterase activity was also reduced significantly by total alkaloidal extract of M. koenigii leaves. The IC50 value of MKA against BACE1 was 1.7 μg/mL. In conclusion, this study indicates MKA to be a useful remedy in the management of Alzheimer's disease and dementia.
  10. Taufiqurrahman I, Ahmad A, Mustapha M, Lenggo Ginta T, Ady Farizan Haryoko L, Ahmed Shozib I
    Materials (Basel), 2021 Feb 27;14(5).
    PMID: 33673716 DOI: 10.3390/ma14051129
    Welding parameters obviously determine the joint quality during the resistance spot welding process. This study aimed to investigate the effect of welding current and electrode force on the heat input and the physical and mechanical properties of a SS316L and Ti6Al4V joint with an aluminum interlayer. The weld current values used in this study were 11, 12, and 13 kA, while the electrode force values were 3, 4, and 5 kN. Welding time and holding time remained constant at 30 cycles. The study revealed that, as the welding current and electrode force increased, the generated heat input increased significantly. The highest tensile-shear load was recorded at 8.71 kN using 11 kA of weld current and 3 kN of electrode force. The physical properties examined the formation of a brittle fracture and several weld defects on the high current welded joint. The increase in weld current also increased the weld diameter. The microstructure analysis revealed no phase transformation on the SS316L interface; instead, the significant grain growth occurred. The phase transformation has occurred on the Ti6Al4V interface. The intermetallic compound layer was also investigated in detail using the EDX (Energy Dispersive X-Ray) and XRD (X-Ray Diffraction) analyses. It was also found that both stainless steel and titanium alloy have their own fusion zone, which is indicated by the highest microhardness value.
  11. Chaudhry MH, Ahmad A, Gulzar Q, Farid MS, Shahabi H, Al-Ansari N
    Sensors (Basel), 2021 Feb 27;21(5).
    PMID: 33673425 DOI: 10.3390/s21051649
    Unmanned Aerial Vehicle (UAV) is one of the latest technologies for high spatial resolution 3D modeling of the Earth. The objectives of this study are to assess low-cost UAV data using image radiometric transformation techniques and investigate its effects on global and local accuracy of the Digital Surface Model (DSM). This research uses UAV Light Detection and Ranging (LIDAR) data from 80 meters and UAV Drone data from 300 and 500 meters flying height. RAW UAV images acquired from 500 meters flying height are radiometrically transformed in Matrix Laboratory (MATLAB). UAV images from 300 meters flying height are processed for the generation of 3D point cloud and DSM in Pix4D Mapper. UAV LIDAR data are used for the acquisition of Ground Control Points (GCP) and accuracy assessment of UAV Image data products. Accuracy of enhanced DSM with DSM generated from 300 meters flight height were analyzed for point cloud number, density and distribution. Root Mean Square Error (RMSE) value of Z is enhanced from ±2.15 meters to 0.11 meters. For local accuracy assessment of DSM, four different types of land covers are statistically compared with UAV LIDAR resulting in compatibility of enhancement technique with UAV LIDAR accuracy.
  12. Ahmad A, Sheikh Abdullah SR, Hasan HA, Othman AR, Ismail N'
    J Environ Manage, 2021 Jun 01;287:112271.
    PMID: 33706093 DOI: 10.1016/j.jenvman.2021.112271
    The aquaculture industry has become increasingly important and is rapidly growing in terms of providing a protein food source for human consumption. With the increase in the global population, demand for aquaculture is high and is estimated to reach 62% of the total global production by 2030. In 2018, it was reported that the demand for aquaculture was 46% of the total production, and with the current positive trends, it may be possible to increase tremendously in the coming years. China is still one of the main players in global aquaculture production. Due to high demand, aquaculture production generates large volumes of effluent, posing a great danger to the environment. Aquaculture effluent comprises solid waste and dissolved constituents, including nutrients and contaminants of emerging concern, thereby bringing detrimental impacts such as eutrophication, chemical toxicity, and food insecurity. Waste can be removed through culture systems, constructed wetlands, biofloc, and other treatment technologies. Some methods have the potential to be applied as zero-waste discharge treatment. Thus, this article analyses the supply and demand for aquaculture products, the best practices adopted in the aquaculture industry, effluent characteristics, current issues, and effluent treatment technology.
  13. Singh PKM, Noor MIM, Jaafar R, Ahmad A, Mohamad I
    Medeni Med J, 2021;36(1):75-79.
    PMID: 33828894 DOI: 10.5222/MMJ.2021.37539
    Retropharyngeal calcific tendonitis (RCT) is an aseptic inflammatory process of the superior oblique tendons of the longus colli muscle caused by the deposition of calcium hydroxyapatite crystals. We reported a 23-year-old woman who presented with a sudden onset of neck pain with odynophagia after waking up from sleep. Physical examination showed paracervical point tenderness with limited neck movement in all directions. Prior to surgery, further imaging was requested to aid in diagnosis, which in turn revealed RCT. It is important to be aware that RCT presentation may mimic other severe conditions such as retropharyngeal space abscess or meningitis.
  14. Villines TC, Ahmad A, Petrini M, Tang W, Evans A, Rush T, et al.
    Eur Heart J Cardiovasc Pharmacother, 2019 Apr 01;5(2):80-90.
    PMID: 30500885 DOI: 10.1093/ehjcvp/pvy044
    AIMS: We used the US Department of Defense Military Health System database to compare the safety and effectiveness of direct oral anticoagulants (DOACs) in patients with non-valvular atrial fibrillation (NVAF) initiating dabigatran vs. rivaroxaban or apixaban.
    METHODS AND RESULTS: Two cohorts of adults with NVAF, newly initiated on standard-dose DOAC, were identified based on clinical approval dates: July 2011-June 2016 for dabigatran (150 mg b.i.d.) or rivaroxaban (20 mg QD) and January 2013-June 2016 for dabigatran (150 mg b.i.d.) or apixaban (5 mg b.i.d.). Propensity score matching (1:1) identified two well-balanced cohorts (dabigatran vs. rivaroxaban n = 12 763 per treatment group; dabigatran vs. apixaban n = 4802 per treatment group). In both cohorts, baseline characteristics and follow-up duration were similar between treatment groups. Patients newly initiating dabigatran had significantly lower risk of major bleeding vs. rivaroxaban [2.08% vs. 2.53%; hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.70-0.97; P = 0.018], while stroke risk was similar (0.60% vs. 0.78%; HR 0.77, 95% CI 0.57-1.04; P = 0.084). The dabigatran vs. apixaban cohort analysis found no differences in risk of major bleeding (1.60% vs. 1.21%; HR 1.37, 95% CI 0.97-1.94; P = 0.070) or stroke (0.44% vs. 0.35%; HR 1.26, 95% CI 0.66-2.39; P = 0.489).
    CONCLUSION: Among NVAF patients newly initiated on standard-dose DOAC therapy in this study, dabigatran was associated with significantly lower major bleeding risk vs. rivaroxaban, and no significant difference in stroke risk. For dabigatran vs. apixaban, the reduced sample size limited the ability to draw definitive conclusions.
    Study site: Department of Defense (DoD) Military Health System, United States
  15. Rayung M, Aung MM, Su'ait MS, Chuah Abdullah L, Ahmad A, Lim HN
    ACS Omega, 2020 Jun 23;5(24):14267-14274.
    PMID: 32596563 DOI: 10.1021/acsomega.9b04348
    Biobased polymers are useful materials in substituting conventional petroleum-derived polymers because of their good properties, ready availability, and abundance in nature. This study reports a new jatropha oil-based gel polymer electrolyte (GPE) for use in dye-sensitized solar cells (DSSCs). The GPE was prepared by mixing jatropha oil-based polyurethane acrylate (PUA) with different concentrations of lithium iodide (LiI). The GPE was characterized by infrared spectroscopy, thermal analysis, lithium nuclear magnetic resonance analysis, electrochemical analysis, and photocurrent conversion efficiency. The highest room-temperature ionic conductivity of 1.88 × 10-4 S cm-1 was obtained at 20 wt % of LiI salt. Additionally, the temperature-dependent ionic conductivity of the GPE exhibited Arrhenius behavior with an activation energy of 0.42 eV and a pre-exponential factor of 1.56 × 103 S cm-1. The electrochemical stability study showed that the PUA GPE was stable up to 2.35 V. The thermal stability of the gel electrolyte showed an improvement after the addition of the salt, suggesting a strong intermolecular interaction between PUA and Li, which leads to polymer-salt complexation, as proven by Fourier transform infrared spectroscopy analysis. A DSSC has been assembled using the optimum ionic conductivity gel electrolyte which indicated 1.2% efficiency under 1 sun condition. Thus, the jatropha oil-based GPE demonstrated favorable properties that make it a promising alternative to petroleum-derived polymer electrolytes in DSSCs.
  16. Nurnazahiah A, Shahril MR, Syamimi ZN, Ahmad A, Sulaiman S, Lua PL
    Health Qual Life Outcomes, 2020 Aug 06;18(1):259.
    PMID: 32762686 DOI: 10.1186/s12955-020-01513-x
    An amendment to this paper has been published and can be accessed via the original article.
  17. Fahad Ahmad A, Aziz SHA, Abbas Z, Mohammad Abdalhadi D, Khamis AM, Aliyu US
    Polymers (Basel), 2020 Aug 26;12(9).
    PMID: 32858790 DOI: 10.3390/polym12091919
    This article describes attenuation and absorption measurements using the microstrip transmission line technique connected with a microwave vector network analyzer (Agilent 8750B). The magnitudes of the reflection (S11) and transmission (S21) coefficients obtained from the microstrip transmission line were used to determine the attenuation and absorption of oil palm empty fruit bunch/polylactic acid (OPEFB/PLA) composites in a frequency range between 0.20 GHz and 12 GHz at room temperature. The main structure of semi-flexible substrates (OPEFF/PLA) was fabricated using different fiber loading content extracted from oil palm empty fruit bunch (OPEFB) trees hosted in polylactic acid (PLA) using the Brabender blending machine, which ensured mixture homogeneity. The commercial software package, Computer Simulation Technology Microwave Studio (CSTMWS), was used to investigate the microstrip line technique performance by simulating and determine the S11 and S21 for microwave substrate materials. Results showed that the materials' transmission, reflection, attenuation, and absorption properties could be controlled by changing the percentage of OPEFB filler in the composites. The highest absorption loss was calculated for the highest percentage of filler (70%) OPEFB at 12 GHz to be 0.763 dB, while the lowest absorption loss was calculated for the lowest percentage of filler 30% OPEFB at 12 GHz to be 0.407 dB. Finally, the simulated and measured results were in excellent agreement, but the environmental conditions slightly altered the results. From the results it is observed that the value of the dielectric constant (εr') and loss factor (εr″) is higher for the OPEFB/PLA composites with a higher content of OPEFB filler. The dielectric constant increased from 2.746 dB to 3.486 dB, while the loss factor increased from 0.090 dB to 0.5941 dB at the highest percentage of 70% OPEFB filler. The dielectric properties obtained from the open-ended coaxial probe were required as input to FEM to calculate the S11 and S21 of the samples.
  18. Ali Khan M, Govindasamy R, Ahmad A, Siddiqui MR, Alshareef SA, Hakami AAH, et al.
    Polymers (Basel), 2021 Jan 28;13(3).
    PMID: 33525497 DOI: 10.3390/polym13030419
    Agglomeration and restacking can reduce graphene oxide (GO) activity in a wide range of applications. Herein, GO was synthesized by a modified Hummer's method. To minimize restacking and agglomeration, in situ chemical oxidation polymerization was carried out to embed polyaniline (PANI) chains at the edges of GO sheets, to obtain GO-PANI nanocomposite. The GO-PANI was tested for the adsorptive removal of brilliant green (BG) from an aqueous solution through batch mode studies. Infrared (FT-IR) analysis revealed the dominance of hydroxyl and carboxylic functionalities over the GO-PANI surface. Solution pH-dependent BG uptake was observed, with maximum adsorption at pH 7, and attaining equilibrium in 30 min. The adsorption of BG onto GO-PANI was fit to the Langmuir isotherm, and pseudo-second-order kinetic models, with a maximum monolayer adsorption capacity (qm) of 142.8 mg/g. An endothermic adsorption process was observed. Mechanistically, π-π stacking interaction and electrostatic interaction played a critical role during BG adsorption on GO-PANI.
  19. Fatmahardi I, Mustapha M, Ahmad A, Derman MN, Lenggo Ginta T, Taufiqurrahman I
    Materials (Basel), 2021 Apr 30;14(9).
    PMID: 33946335 DOI: 10.3390/ma14092336
    Resistance spot welding (RSW) is one of the most effective welding methods for titanium alloys, in particular Ti-6Al-4V. Ti-6Al-4V is one of the most used materials with its good ductility, high strength, weldability, corrosion resistance, and heat resistance. RSW and Ti-6Al-4V materials are often widely used in industrial manufacturing, particularly in automotive and aerospace industries. To understand the phenomenon of resistance spot weld quality, the physical and mechanical properties of Ti-6Al-4V spot weld are essential to be analyzed. In this study, an experiment was conducted using the Taguchi L9 method to find out the optimum level of the weld joint strength. The given optimum level sample was analyzed to study the most significant affecting RSW parameter, the failure mode, the weld nugget microstructure, and hardness values. The high heat input significantly affect the weld nugget temperature to reach and beyond the β-transus temperature. It led to an increase in the weld nugget diameter and the indentation depth. The expulsion appeared in the high heat input and decreased the weld nugget strength. It was caused by the molten material ejection in the fusion zone. The combination of high heat input and rapid air cooling at room temperature generated a martensite microstructure in the fusion zone. It increased the hardness, strength, and brittleness but decreased the ductility.
  20. Rahman MA, Yusoff MSB, Roslan NS, Mohammad JA, Ahmad A
    BMC Health Serv Res, 2021 May 21;21(1):482.
    PMID: 34016095 DOI: 10.1186/s12913-021-06542-w
    PURPOSE: Most of the resilience scales were developed for the non-medical population, therefore the purpose of this study was developing and validating a resilience scale for medical professionals - namely Medical Professionals Resilience Scale (MeRS).

    METHODS: A questionnaire development and validation study was conducted. The resilience domains and items were identified and generated through a literature review. The content validation was carried out by content experts and the content validity index (CVI) was calculated. The face validation was performed by medical officers and the face validity index (FVI) was calculated. The final MeRS was administered to 167 medical officers, exploratory factor analysis (EFA) and reliability analysis were performed to assess MeRS's factorial structure and internal consistency.

    RESULTS: Four domains with 89 items of medical professionals' resilience were developed. Following that, the content and face validation was conducted, and a total of 41-items remained for construct validation. EFA extracted four factors, namely growth, control, involvement, and resourceful, with a total of 37 items. The items' CVI and FVI values were more than 0.80. The final MeRS's items had factor loading values ranged from 0.41 to 0.76, and the Cronbach's alpha values of the resilience domains ranged from 0.72 to 0.89.

    CONCLUSIONS: MeRS is a promising scale for measuring medical professionals' resilience as it showed good psychometric properties. This study provided validity evidence in terms of content, response process, and internal structure that supported the validity of MeRS in the measurement of resilience domains among medical professionals.

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