Displaying publications 341 - 360 of 668 in total

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  1. Al-Worafi YM, Kassab YW, Alseragi WM, Almutairi MS, Ahmed A, Ming LC, et al.
    Ther Clin Risk Manag, 2017;13:1175-1181.
    PMID: 28924350 DOI: 10.2147/TCRM.S140674
    OBJECTIVE: The aim of this study was to compare the knowledge, attitude and barriers of pharmacy technicians and pharmacists toward pharmacovigilance, adverse drug reactions (ADRs) and ADR reporting in community pharmacies in Yemen.

    METHODS: This cross-sectional survey was conducted among community pharmacists and pharmacy technicians in the capital of Yemen, Sana'a. A total of 289 community pharmacies were randomly selected. The validated and pilot-tested questionnaire consisted of six sections: demographic data, knowledge about pharmacovigilance, experience with ADR reporting, attitudes toward ADR reporting, and the facilitators to improve ADR reporting.

    RESULTS: A total of 428 pharmacy technicians and pharmacists were contacted and 179 went on to complete a questionnaire (response rate: 41.8%). Of the 179 respondents, 21 (11.7%) were pharmacists and 158 (88.3%) were pharmacy technicians, of which, 176 (98.3%) were male and 3 (1.7%) were female. The mean age of the respondents was 25.87±2.63 years. There was a significant difference between the pharmacists and pharmacy technicians in terms of knowledge scores (P<0.05). The mean knowledge scores for pharmacists was 3.33±2.852 compared to 0.15±0.666 for pharmacy technicians. With regard to attitudes toward ADR reporting, all pharmacists (100%) showed a positive attitude, while only 43% of pharmacy technicians showed a positive attitude.

    CONCLUSION: Pharmacists have a significantly better knowledge than pharmacy technicians with regard to pharmacovigilance. More than half of pharmacy technicians showed a negative attitude toward ADR reporting. Therefore, educational interventions and training is very important for community pharmacists and pharmacy technicians in Yemen to increase their awareness and participation in ADR reporting.

  2. Ng YP, Balasubramanian GP, Heng YP, Kalaiselvan M, Teh YW, Cheong KM, et al.
    Diabetes Metab Syndr, 2018 May;12(3):305-308.
    PMID: 29279269 DOI: 10.1016/j.dsx.2017.12.005
    AIMS: Recent data showed an alarming rise of new dialysis cases secondary to diabetic nephropathy despite the growing usage of RAAS blockers. Primary objective of this study is to explore the prevalence of RAAS blockers usage among type II diabetic patients, secondary objectives are to compare the prescribing pattern of RAAS blocker between primary and tertiary care center and to explore if the dose of RAAS blocker prescribed was at optimal dose as suggested by trials.

    MATERIALS AND METHODS: This is a retrospective study conducted at one public tertiary referral hospital and one public health clinic in Sungai Petani, Kedah, Malaysia.

    RESULTS: RAAS blockers in T2DM patients was found to be 65%. In primary care, 14.3% of the RAAS blockers prescribed was ARB. Tertiary care had higher utilization of ARB, which was 42.9%. In primary care setting, the most commonly used ACEI were perindopril (92.4%) followed by enalapril (7.6%), meanwhile perindopril was the only ACEI being prescribed in tertiary care. The most prescribed ARB was irbesartan (63.6%) and telmisartan (54.2%) respectively in primary and tertiary care. Overall, 64.9% of RAAS blockers prescribed by both levels of care were found to be achieving the target dose as recommended in landmark trials. Crude odd ratio of prescribing RAAS blocker in primary care versus tertiary care was reported as 2.70 (95% CI: 1.49 to 4.91).

    CONCLUSION: RAAS blockers usage among T2DM patients was higher in primary care versus tertiary care settings. Majority of the patients did not receive optimal dose of RAAS blockers.
  3. Salmasi S, Lee KS, Ming LC, Neoh CF, Elrggal ME, Babar ZD, et al.
    BMC Cancer, 2017 12 28;17(1):903.
    PMID: 29282008 DOI: 10.1186/s12885-017-3888-y
    BACKGROUND: Globally, cancer is one of the leading causes of mortality. High treatment cost, partly owing to higher prices of anti-cancer drugs, presents a significant burden on patients and healthcare systems. The aim of the present study was to survey and compare retail prices of anti-cancer drugs between high, middle and low income countries in the South-East Asia, Western Pacific and Eastern Mediterranean regions.

    METHODS: Cross-sectional survey design was used for the present study. Pricing data from ten counties including one from South-East Asia, two from Western Pacific and seven from Eastern Mediterranean regions were used in this study. Purchasing power parity (PPP)-adjusted mean unit prices for 26 anti-cancer drug presentations (similar pharmaceutical form, strength, and pack size) were used to compare prices of anti-cancer drugs across three regions. A structured form was used to extract relevant data. Data were entered and analysed using Microsoft Excel®.

    RESULTS: Overall, Taiwan had the lowest mean unit prices while Oman had the highest prices. Six (23.1%) and nine (34.6%) drug presentations had a mean unit price below US$100 and between US$100 and US$500 respectively. Eight drug presentations (30.7%) had a mean unit price of more than US$1000 including cabazitaxel with a mean unit price of $17,304.9/vial. There was a direct relationship between income category of the countries and their mean unit price; low-income countries had lower mean unit prices. The average PPP-adjusted unit prices for countries based on their income level were as follows: low middle-income countries (LMICs): US$814.07; high middle income countries (HMICs): US$1150.63; and high income countries (HICs): US$1148.19.

    CONCLUSIONS: There is a great variation in pricing of anticancer drugs in selected countires and within their respective regions. These findings will allow policy makers to compare prices of anti-cancer agents with neighbouring countries and develop policies to ensure accessibility and affordability of anti-cancer drugs.

  4. Ming LC, Hameed MA, Lee DD, Apidi NA, Lai PSM, Hadi MA, et al.
    Ther Innov Regul Sci, 2016 Jul;50(4):419-426.
    PMID: 30227023 DOI: 10.1177/2168479015624732
    BACKGROUND: Handheld computers (HHCs) such as smartphones and tablets are providing a variety of drug information (DI) applications to assist pharmacists' decision making in the clinical and hospital setting. However, little is known about the extent of their use among Malaysian pharmacists. The current study aimed to assess the use of electronic DI resources via HHCs by pharmacists in Malaysia. This study also aimed to investigate the pharmacists' perception toward the DI content and functions of mobile medical applications.

    METHODS: A convenience sampling method was adopted to invite pharmacists (N = 450) working in various sectors such as hospitals, the drug approval authority, and academia to participate in this online survey. A 36-item questionnaire was administered, and data were summarized and presented using descriptive statistics.

    RESULTS: The response rate to this survey was 49.8% (n = 224). Overall, 213 respondents (95.1%) were active HHCs users in their daily clinical practice. About 194 respondents (86.6%) disclosed that they often use HHCs for searching DI. Dosage recommendations (n = 198; 88.4%), adverse drug reactions (n = 153; 68.3%), and drug interactions (n = 146; 65.2%) were the most common DI retrieved. Meanwhile, general dosage recommendation, pediatric dosage recommendations and dosage recommendations for renal failure were ranked as the most important DI in mobile medical applications. Gaining access to the latest information on drugs and clinical practice were regarded as the most important functions of the mobile medical app.

    CONCLUSIONS: The use of HHCs for DI among pharmacists in Malaysia was high. The use of locally produced DI sources is still low compared to overseas sources. The most popular applications used for drug-related medical information were Micromedex, followed by Lexicomp and Medscape.

  5. Koupaei Malek S, Gabris MA, Hadi Jume B, Baradaran R, Aziz M, Karim KJBA, et al.
    Daru, 2019 Jun;27(1):9-20.
    PMID: 30554368 DOI: 10.1007/s40199-018-0232-2
    Polyethylene glycol functionalized with oxygenated multi-walled carbon nanotubes (O-PEG-MWCNTs) as an efficient nanomaterial for the in vitro adsorption/release of curcumin (CUR) anticancer agent. The synthesized material was morphologically characterized using scanning electron microscopy, Fourier transform infrared spectroscopy and transmission electron microscopy. In addition, the CUR adsorption process was assessed with kinetic and isotherm models fitting well with pseudo-second order and Langmuir isotherms. The results showed that the proposed O-PEG-MWCNTs has a high adsorption capacity for CUR (2.0 × 103 mg/g) based on the Langmuir model. The in vitro release of CUR from O-PEG-MWCNTs was studied in simulating human body fluids with different pHs (ABS pH 5, intestinal fluid pH 6.6 and body fluid pH 7.4). Lastly, to confirm the success compliance of the O-PEG-MWCNT nanocomposite as a drug delivery system, the parameters affecting the CUR release such as temperature and PEG content were investigated. As a result, the proposed nanocomposite could be used as an efficient carrier for CUR delivery with an enhanced prolonged release property. Graphical Abstract ᅟ.
  6. Venkatason P, Zubairi YZ, Wan Ahmad WA, Hafidz MI, Ismail MD, Hadi MF, et al.
    BMJ Open, 2019 05 05;9(5):e025734.
    PMID: 31061031 DOI: 10.1136/bmjopen-2018-025734
    OBJECTIVES: Cardiogenic shock (CS) complicating ST-elevation myocardial infarction (STEMI) carries an extremely high mortality. The clinical pattern of this life threatening complication has never been described in Malaysian setting. This study is to investigate the incidence, clinical characteristics and outcome of STEMI patients with CS in our population.

    DESIGN: A retrospective analysis of STEMI patients from 18 hospitals across Malaysia contributing to the Malaysian National Cardiovascular Database-acute coronary syndrome) registry (NCVD-ACS) year 2006-2013.

    PARTICIPANTS: 16 517 patients diagnosed of STEMI from 18 hospitals in Malaysia from the year 2006 to 2013.

    PRIMARY OUTCOME MEASURES: In-hospital and 30 day post-discharge mortality.

    RESULTS: CS complicates 10.6% of all STEMIs in this study. They had unfavourable premorbid conditions and poor outcomes. The in-hospital mortality rate was 34.1% which translates into a 7.14 times mortality risk increment compared with STEMI without CS. Intravenous thrombolysis remained as the main urgent reperfusion modality. Percutaneous coronary interventions (PCI) in CS conferred a 40% risk reduction over non-invasive therapy but were only done in 33.6% of cases. Age over 65, diabetes mellitus, hypertension, chronic lung and kidney disease conferred higher risk of mortality.

    CONCLUSION: Mortality rates of CS complicating STEMI in Malaysia are high. In-hospital PCI confers a 40% mortality risk reduction but the rate of PCI among our patients with CS complicating STEMI is still low. Efforts are being made to increase access to invasive therapy for these patients.

  7. Fitriani N, Kusuma MN, Wirjodirdjo B, Hadi W, Hermana J, Ni'matuzahroh, et al.
    Heliyon, 2020 Sep;6(9):e04967.
    PMID: 33015386 DOI: 10.1016/j.heliyon.2020.e04967
    In a slow sand filter, a biological layer consisting of alluvial mud and various types of microorganisms grows and attaches to the sand media and forms a matrix called schmutzdecke. Changes to several factors, including the quality of raw water, filtration speed, and the addition of media, affect the performance of the slow sand filter unit in producing treated water. Geotextiles can be equipped to improve the performance of a slow sand filter in removing pollutants. The selection of several factors that affect slow sand filter performance can be used as a starting point for the engineering system to determine the best pattern of performance behavior. This approach was carried out by looking at the dynamic behavior patterns of slow sand filter system performance in treating raw water. This research has not yet been conducted extensively. The dynamic behavior pattern approach to the performance of the slow sand filter unit was used to obtain the behavior model for the schmutzdecke layer on the filter. The system dynamic approach focused on treatment scenarios that can determine the behavior of the slow sand filter system. Several factors were assessed, including temperature, turbidity, nutrient concentration, algal concentration, bacteria and dissolved oxygen. Model simulation results show that the comparison of C: N: P values affected the performance of the schmutzdecke layer in removing total coli. The slow sand filter unit was capable of producing treated water with a total amount of coli equal to 0 on the C: N: P values of 85: 5.59: 1.25, respectively, and a 9 cm geotextile thickness.
  8. Wilkinson CL, Chua KWJ, Fiala R, Liew JH, Kemp V, Hadi Fikri A, et al.
    Ecology, 2021 01;102(1):e03199.
    PMID: 32969053 DOI: 10.1002/ecy.3199
    In Southeast Asia, biodiversity-rich forests are being extensively logged and converted to oil palm monocultures. Although the impacts of these changes on biodiversity are largely well documented, we know addition to samples we collected in 201 little about how these large-scale impacts affect freshwater trophic ecology. We used stable isotope analyses (SIA) to determine the impacts of land-use changes on the relative contribution of allochthonous and autochthonous basal resources in 19 stream food webs. We also applied compound-specific SIA and bulk-SIA to determine the trophic position of fish apex predators and meso-predators (invertivores and omnivores). There was no difference in the contribution of autochthonous resources in either consumer group (70-82%) among streams with different land-use type. There was no change in trophic position for meso-predators, but trophic position decreased significantly for apex predators in oil palm plantation streams compared to forest streams. This change in maximum food chain length was due to turnover in identity of the apex predator among land-use types. Disruption of aquatic trophic ecology, through reduction in food chain length and shift in basal resources, may cause significant changes in biodiversity as well as ecosystem functions and services. Understanding this change can help develop more focused priorities for mediating the negative impacts of human activities on freshwater ecosystems.
  9. Aziz SB, M Hadi J, Dannoun EMA, Abdulwahid RT, R Saeed S, Shahab Marf A, et al.
    Polymers (Basel), 2020 Aug 27;12(9).
    PMID: 32867191 DOI: 10.3390/polym12091938
    In this study, plasticized films of polyvinyl alcohol (PVA): chitosan (CS) based electrolyte impregnated with ammonium thiocyanate (NH4SCN) were successfully prepared using a solution-casting technique. The structural features of the electrolyte films were investigated through the X-ray diffraction (XRD) pattern. The enrichment of the amorphous phase with increasing glycerol concentration was confirmed by observing broad humps. The electrical impedance spectroscopy (EIS) portrays the improvement of ionic conductivity from 10-5 S/cm to 10-3 S/cm upon the addition of plasticizer. The electrolytes incorporated with 28 wt.% and 42 wt.% of glycerol were observed to be mainly ionic conductor as the ionic transference number measurement (TNM) was found to be 0.97 and 0.989, respectively. The linear sweep voltammetry (LSV) investigation indicates that the maximum conducting sample is stable up to 2 V. An electrolyte with the highest conductivity was used to make an energy storage electrical double-layer capacitor (EDLC) device. The cyclic voltammetry (CV) plot depicts no distinguishable peaks in the polarization curve, which means no redox reaction has occurred at the electrode/electrolyte interface. The fabricated EDLC displays the initial specific capacitance, equivalent series resistance, energy density, and power density of 35.5 F/g, 65 Ω, 4.9 Wh/kg, and 399 W/kg, respectively.
  10. Noviany N, Samadi A, Yuliyan N, Hadi S, Aziz M, Purwitasari N, et al.
    Phytochem Lett, 2020 Feb;35:211-215.
    PMID: 32863985 DOI: 10.1016/j.phytol.2019.12.008
    A new 2-arylbenzofuran, sesbagrandiflorain C (1), together with four known compounds, 2-(3,4-dihydroxy-2-methoxyphenyl)-4-hydroxy-6-methoxybenzofuran-3-carbaldehyde (2), 2-(4-hydroxy-2-methoxyphenyl)-5,6-dimethoxybenzofuran-3-carboxaldehyde (3), sesbagrandiflorain A (4) and sesbagrandiflorain B (5), have been isolated from the stem bark of an Indonesian plant, Sesbania grandiflora (L.) Pers. The chemical structure of compound 1 was elucidated by UV, IR, MS, and NMR spectroscopic techniques. The proton and carbon NMR resonances of 1 were also compared with the predicted chemical shifts obtained from DFT quantum mechanical calculations with Gaussian. None of the compounds showed antibacterial activity against Bacillus subtilis, Escherichia coli, Mycobacterium smegmatis, Pseudomonas aeruginosa, and Staphylococcus aureus in an agar diffusion assay. However, sesbagrandiflorains A (4) and B (5) exhibited moderate activity against Mycobacterium tuberculosis H37Rv. In addition, compounds 1 - 5 have moderate cytotoxicity against HeLa, HepG2, and MCF-7 cancer cell lines.
  11. Cheema E, McGuinness K, Hadi MA, Paudyal V, Elnaem MH, Alhifany AA, et al.
    J Pain Res, 2020;13:3281-3294.
    PMID: 33324089 DOI: 10.2147/JPR.S280462
    PURPOSE: Fentanyl poisoning has been widely reported, yet there is a lack of systematic evaluation of the nature and toxicology of associated deaths in the published literature. This article aims to systematically review the nature, causes, routes of administration and toxicology of fentanyl-associated deaths using case studies and case series in peer-reviewed published literature.

    METHODS: Four electronic databases including Embase, Medline (via Ovid), Scopus and Google Scholar were searched from inception until October 2019 to identify the studies reporting fentanyl related deaths. Two independent reviewers screened and selected the titles and then evaluated the full texts. Only case studies and case series were included. A structured data extraction tool was used to extract data on the number of deaths, routes of administration, concomitant drug use and toxicological data. The Joanna Briggs Institute quality assessment tool was used to evaluate the quality of included studies. Data were synthesized narratively.

    RESULTS: Of 1251 articles identified during initial search, 8 case reports and 9 case series met the inclusion criteria. A total of 1969 deaths were reported in the included studies. Deaths were concentrated in the north American region (n = 1946) and the Nordic region (n = 22). Reported causes of death included fentanyl overdose (n = 321, 56.4%), mixed drug toxicity (n = 196, 34.5%), natural (n = 28, 4.9%), other drug toxicity (n = 10, 1.8%), fentanyl and ethanol intoxication (n = 8, 1.4%), incidental (n = 5, <1%) and aspiration (n = 1). Most common routes of use were intravenous (70.5%) and transdermal routes (23.0%). Deaths came swiftly via the intravenous route. Mean level of blood fentanyl amongst all reported deaths was 0.024 µg/mL.

    CONCLUSION: Literature related to fentanyl-associated deaths predominantly come from North America. Deaths are comparatively lower or not reported in peer-reviewed publications from the rest of the world. Abuse through intravenous administration, mixed drug toxicities and self-treatment of breakthrough pain are mainly responsible for majority of the reported deaths.

  12. Iijima C, Wong CP, Nugroho AE, Sotozono Y, Someya S, Hirasawa Y, et al.
    J Nat Med, 2016 Oct;70(4):702-7.
    PMID: 27357963 DOI: 10.1007/s11418-016-1016-y
    The ceramicines, a series of limonoids from Chisocheton ceramicus (Meliaceae), were evaluated for anti-melanin deposition activity on α-melanocyte stimulating hormone (α-MSH) and 3-isobutyl-1-methylxanthine (IBMX)-treated B16-F10 melanoma cell, and several ceramicines were found to be active. The structure-activity relationship of ceramicines as anti-melanin deposition inhibitors was deduced. Furthermore, the mechanism of anti-melanin deposition activity of ceramicine B, a major constituent of C. ceramicus that showed potent anti-melanin deposition activity, was investigated. Tyrosinase enzymatic activity and tyrosinase mRNA expression were not affected by ceramicine B. The anti-melanin deposition activity of ceramicine B was shown to be related to the downregulation of tyrosinase protein expression. These results suggest that ceramicines have potential to be used as depigmentation agents.
  13. Mohd Mujar NM, Dahlui M, Emran NA, Abdul Hadi I, Wai YY, Arulanantham S, et al.
    PLoS One, 2017;12(4):e0176394.
    PMID: 28448541 DOI: 10.1371/journal.pone.0176394
    Complementary and alternative medicine (CAM) is widely used among the breast cancer patients in Malaysia. Delays in presentation, diagnosis and treatment have been shown to impact the disease prognosis. There is considerable use of CAM amongst breast cancer patients. CAM use has been cited as a cause of delay in diagnosis and treatments in qualitative studies, however there had not been any confirmatory study that confirms its impact on delays. The purpose of this study was to evaluate whether the use of CAM among newly diagnosed breast cancer patients was associated with delays in presentation, diagnosis or treatment of breast cancer. This multi-centre cross-sectional study evaluating the time points of the individual breast cancer patients' journey from first visit, resolution of diagnosis and treatments was conducted in six public hospitals in Malaysia. All newly diagnosed breast cancer patients from 1st January to 31st December 2012 were recruited. Data were collected through medical records review and patient interview by using a structured questionnaire. Complementary and alternative medicine (CAM) was defined as the use of any methods and products not included in conventional allopathic medicine before commencement of treatments. Presentation delay was defined as time taken from symptom discovery to first presentation of more than 3 months. The time points were categorised to diagnosis delay was defined as time taken from first presentation to diagnosis of more than 1 month and treatment delay was defined as time taken from diagnosis to initial treatment of more than 1 month. Multiple logistic regression was used for analysis. A total number of 340 patients participated in this study. The prevalence of CAM use was 46.5% (n = 158). Malay ethnicity (OR 3.32; 95% CI: 1.85, 5.97) and not interpreting symptom as cancerous (OR 1.79; 95% CI: 1.10, 2.92) were significantly associated with CAM use. The use of CAM was associated with delays in presentation (OR 1.65; 95% CI: 1.05, 2.59), diagnosis (OR 2.42; 95% CI: 1.56, 3.77) and treatment of breast cancer (OR 1.74; 95% CI: 1.11, 2.72) on univariate analyses. However, after adjusting with other covariates, CAM use was associated with delays in presentation (OR 1.71; 95% CI: 1.05, 2.78) and diagnosis (OR 2.58; 95% CI: 1.59, 4.17) but not for treatment of breast cancer (OR 1.58; 95% CI: 0.98, 2.55). The prevalence of CAM use among the breast cancer patients was high. Women of Malay ethnicity and not interpreting symptom as cancerous were significantly associated with CAM use. The use of CAM is significantly associated with delay in presentation and resolution of diagnosis. This study suggests further evaluation of access to breast cancer care is needed as poor access may cause the use of CAM. However, since public hospitals in Malaysia are heavily subsidized and readily available to the population, CAM use may impact delays in presentation and diagnosis.
  14. Lim HM, Teo CH, Ng CJ, Chiew TK, Ng WL, Abdullah A, et al.
    JMIR Med Inform, 2021 Feb 26;9(2):e23427.
    PMID: 33600345 DOI: 10.2196/23427
    BACKGROUND: During the COVID-19 pandemic, there was an urgent need to develop an automated COVID-19 symptom monitoring system to reduce the burden on the health care system and to provide better self-monitoring at home.

    OBJECTIVE: This paper aimed to describe the development process of the COVID-19 Symptom Monitoring System (CoSMoS), which consists of a self-monitoring, algorithm-based Telegram bot and a teleconsultation system. We describe all the essential steps from the clinical perspective and our technical approach in designing, developing, and integrating the system into clinical practice during the COVID-19 pandemic as well as lessons learned from this development process.

    METHODS: CoSMoS was developed in three phases: (1) requirement formation to identify clinical problems and to draft the clinical algorithm, (2) development testing iteration using the agile software development method, and (3) integration into clinical practice to design an effective clinical workflow using repeated simulations and role-playing.

    RESULTS: We completed the development of CoSMoS in 19 days. In Phase 1 (ie, requirement formation), we identified three main functions: a daily automated reminder system for patients to self-check their symptoms, a safe patient risk assessment to guide patients in clinical decision making, and an active telemonitoring system with real-time phone consultations. The system architecture of CoSMoS involved five components: Telegram instant messaging, a clinician dashboard, system administration (ie, back end), a database, and development and operations infrastructure. The integration of CoSMoS into clinical practice involved the consideration of COVID-19 infectivity and patient safety.

    CONCLUSIONS: This study demonstrated that developing a COVID-19 symptom monitoring system within a short time during a pandemic is feasible using the agile development method. Time factors and communication between the technical and clinical teams were the main challenges in the development process. The development process and lessons learned from this study can guide the future development of digital monitoring systems during the next pandemic, especially in developing countries.

  15. Hadi AE, Hamdan MHM, Siregar JP, Junid R, Tezara C, Irawan AP, et al.
    Polymers (Basel), 2021 Aug 01;13(15).
    PMID: 34372175 DOI: 10.3390/polym13152572
    Woven laminated composite has gained researchers' and industry's interest over time due to its impressive mechanical performance compared to unidirectional composites. Nevertheless, the mechanical properties of the woven laminated composite are hard to predict. There are many micromechanical models based on unidirectional composite but limited to the woven laminated composite. The current research work was conducted to evaluate elastic moduli of hybrid jute-ramie woven reinforced unsaturated polyester composites using micromechanical effectiveness unidirectional models, such as ROM, IROM, Halpin-Tsai, and Hirsch, which are based on stiffness. The hybrid jute-ramie laminated composite was fabricated with different layering sizes, and the stacking sequence was completed via hand lay-up with the compression machine. Tensile modulus values for hybrid composites are between those for single jute and single ramie. Obtained p-values less than 0.05 prove the relationship between layering size and tensile modulus. This study showed that several micromechanical models, such as Halpin-Tsai's predicted value of homogenized mechanical properties, were in good agreement with the experimental result. In the case of the hybrid composite, the micromechanical model deviates from the experimental result. Several modifications are required to improve the current existing model. A correlation function was calculated based on the differences between the elastic modulus values determined experimentally and those derived from each micromechanical model calculation.
  16. Nugroho AE, Nakajima S, Wong CP, Hirasawa Y, Kaneda T, Shirota O, et al.
    J Nat Med, 2022 Jan;76(1):94-101.
    PMID: 34351584 DOI: 10.1007/s11418-021-01556-4
    Eight new limonoids, walsogynes H-O (1-8) were isolated from the barks of Walsura chrysogyne, and their structures were determined on the basis of the 1D and 2D NMR data. Walsogynes H-M (1-6) and O (8) were concluded to be 11,12-seco limonoids with a dodecahydro-1H-naphtho[1,8-bc:3,4-c']difuran skeleton, and walsogyne N (7) to be 11,12-seco limonoid sharing a unique dodecahydronaphtho[1,8-bc:5,4-b'c']difuran skeleton. Walsogynes H-O (1-8) exhibited potent antimalarial activity against Plasmodium falciparum 3D7 strain with IC50 value of 2.5, 2.6, 1.6, 2.5, 1.5, 2.6, 2.1, and 1.1 µM, respectively.
  17. Ridwan ES, Wiratama BS, Lin MY, Hou WH, Liu MF, Chen CM, et al.
    PLoS One, 2021;16(2):e0246179.
    PMID: 33561132 DOI: 10.1371/journal.pone.0246179
    Reduced peak expiratory flow is a common physiological change in older individuals and age is an important predictor for sarcopenia. We analyzed nationwide survey data to determine the relationship between peak expiratory flow rate and sarcopenia in older Indonesians. Community-dwelling Indonesian individuals aged ≥60 years (n = 2422; mean age = 67.21 y) from the fifth-wave data of the Indonesian Family Life Survey was selected. Sarcopenia was diagnosed based on handgrip strength, gait speed, and appendicular skeletal muscle mass measurements. Peak expiratory flow rates (PEFRs) were categorized according to their percentage of predicted flow rates as <50%, 50% to 80%, and >80%. Confounders previously determined to be associated with sarcopenia occurrence were included. Sarcopenia prevalence was 50.25%. After adjustment for confounders, PEFRs of <50% and 50% to 80% were associated with an increased sarcopenia risk (odds ratio = 5.22 and 1.88, respectively) compared with PEFRs of >80%. Poor lung function was independently associated with sarcopenia occurrence. Future studies should explore the usefulness of PEFR as a risk factor of sarcopenia.
  18. Nofal MM, Hadi JM, Aziz SB, Brza MA, Asnawi ASFM, Dannoun EMA, et al.
    Materials (Basel), 2021 Aug 26;14(17).
    PMID: 34500952 DOI: 10.3390/ma14174859
    In this research, a biopolymer-based electrolyte system involving methylcellulose (MC) as a host polymeric material and potassium iodide (KI) salt as the ionic source was prepared by solution cast technique. The electrolyte with the highest conductivity was used for device application of electrochemical double-layer capacitor (EDLC) with high specific capacitance. The electrical, structural, and electrochemical characteristics of the electrolyte systems were investigated using various techniques. According to electrochemical impedance spectroscopy (EIS), the bulk resistance (Rb) decreased from 3.3 × 105 to 8 × 102 Ω with the increase of salt concentration from 10 wt % to 40 wt % and the ionic conductivity was found to be 1.93 ×10-5 S/cm. The dielectric analysis further verified the conductivity trends. Low-frequency regions showed high dielectric constant, ε' and loss, ε″ values. The polymer-salt complexation between (MC) and (KI) was shown through a Fourier transformed infrared spectroscopy (FTIR) studies. The analysis of transference number measurement (TNM) supported ions were predominantly responsible for the transport process in the MC-KI electrolyte. The highest conducting sample was observed to be electrochemically constant as the potential was swept linearly up to 1.8 V using linear sweep voltammetry (LSV). The cyclic voltammetry (CV) profile reveals the absence of a redox peak, indicating the presence of a charge double-layer between the surface of activated carbon electrodes and electrolytes. The maximum specific capacitance, Cs value was obtained as 118.4 F/g at the sweep rate of 10 mV/s.
  19. Aziz SB, Nofal MM, Kadir MFZ, Dannoun EMA, Brza MA, Hadi JM, et al.
    Materials (Basel), 2021 Apr 16;14(8).
    PMID: 33923484 DOI: 10.3390/ma14081994
    This report shows a simple solution cast methodology to prepare plasticized polyvinyl alcohol (PVA)/methylcellulose (MC)-ammonium iodide (NH4I) electrolyte at room temperature. The maximum conducting membrane has a conductivity of 3.21 × 10-3 S/cm. It is shown that the number density, mobility and diffusion coefficient of ions are enhanced by increasing the glycerol. A number of electric and electrochemical properties of the electrolyte-impedance, dielectric properties, transference numbers, potential window, energy density, specific capacitance (Cs) and power density-were determined. From the determined electric and electrochemical properties, it is shown that PVA: MC-NH4I proton conducting polymer electrolyte (PE) is adequate for utilization in energy storage device (ESD). The decrease of charge transfer resistance with increasing plasticizer was observed from Bode plot. The analysis of dielectric properties has indicated that the plasticizer is a novel approach to increase the number of charge carriers. The electron and ion transference numbers were found. From the linear sweep voltammetry (LSV) response, the breakdown voltage of the electrolyte is determined. From Galvanostatic charge-discharge (GCD) measurement, the calculated Cs values are found to drop with increasing the number of cycles. The increment of internal resistance is shown by equivalent series resistance (ESR) plot. The energy and power density were studied over 250 cycles that results to the value of 5.38-3.59 Wh/kg and 757.58-347.22 W/kg, respectively.
  20. Aziz SB, Asnawi ASFM, Kadir MFZ, Alshehri SM, Ahamad T, Yusof YM, et al.
    Polymers (Basel), 2021 Apr 07;13(8).
    PMID: 33916979 DOI: 10.3390/polym13081183
    In this work, a pair of biopolymer materials has been used to prepare high ion-conducting electrolytes for energy storage application (ESA). The chitosan:methylcellulose (CS:MC) blend was selected as a host for the ammonium thiocyanate NH4SCN dopant salt. Three different concentrations of glycerol was successfully incorporated as a plasticizer into the CS-MC-NH4SCN electrolyte system. The structural, electrical, and ion transport properties were investigated. The highest conductivity of 2.29 × 10-4 S cm-1 is recorded for the electrolyte incorporated 42 wt.% of plasticizer. The complexation and interaction of polymer electrolyte components are studied using the FTIR spectra. The deconvolution (DVN) of FTIR peaks as a sensitive method was used to calculate ion transport parameters. The percentage of free ions is found to influence the transport parameters of number density (n), ionic mobility (µ), and diffusion coefficient (D). All electrolytes in this work obey the non-Debye behavior. The highest conductivity electrolyte exhibits the dominancy of ions, where the ionic transference number, tion value of (0.976) is near to infinity with a voltage of breakdown of 2.11 V. The fabricated electrochemical double-layer capacitor (EDLC) achieves the highest specific capacitance, Cs of 98.08 F/g at 10 mV/s by using the cyclic voltammetry (CV) technique.
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