MyMedR

Displaying publications 161 - 180 of 364 in total

Abstract:

Sort:

Fulltext What are the direct medical costs of managing type 2 diabetes mellitus in Malaysia?

Feisul IM, Azmi S, Mohd Rizal AM, Zanariah H, Nik Mahir NJ, Fatanah I, et al.

Med J Malaysia, 2017 10;72(5):271-277.
PMID: 29197881 MyJurnal

INTRODUCTION: An economic analysis was performed to estimate the annual cost of diabetes mellitus to Malaysia.

METHODS: We combined published data and clinical pathways to estimate cost of follow-up and complications, then calculated the overall national cost. Costs consisted of diabetes follow-up and complications costs.

RESULTS: Patient follow-up was estimated at RM459 per year. Complications cost were RM42,362 per patient per year for nephropathy, RM4,817 for myocardial infarction, RM5,345 for stroke, RM3,880 for heart failure, RM5,519 for foot amputation, RM479 for retinopathy and RM4,812 for cataract extraction.

CONCLUSION: Overall, we estimated the total cost of diabetes as RM2.04 billion per year for year 2011 (both public and private sector). Of this, RM1.40 billion per year was incurred by the government. Despite some limitations, we believe our study provides insight to the actual cost of diabetes to the country. The high cost to the nation highlights the importance of primary and secondary prevention.
Fulltext Lernaea cyprinacea Linnaeus, 1758 (Copepoda: Lernaeidae) infection on Betta rubra Perugia, 1893 (Anabantiformes: Osphronemidae) from Aceh Province, Indonesia

Nur FM, Batubara AS, Fadli N, Rizal S, Siti-Azizah MN, Wilkes M, et al.

Rev Bras Parasitol Vet, 2022;31(1):e020421.
PMID: 35293430 DOI: 10.1590/S1984-29612022015

Betta rubra is an ornamental freshwater fish endemic to northern Sumatra, Indonesia. The B. rubra population has decreased in recent decades, and is classified as an endangered species in the IUCN Red List. This study aims to report for the first time infection by L. cyprinacea in B. rubra harvested from the Aceh Besar region of Indonesia. The fish samples were obtained from the Cot Bira tributaries, Aceh Besar District, Indonesia from January to December 2020. The results showed that the parasite infected 6 out of 499 samples in August and September, with a prevalence and intensity rate of 1% and 2 parasites/fish, respectively. The eyes and pectoral fins were the common infection sites. Despite B. rubra is not an optimal host (small size) for the parasite, this parasite might serve as additional threatening factors for the endangered B. rubra fish population.
Fulltext Active Ageing Awareness and Quality of Life among Pre-Elder Malaysian Public Employees

Bahuri NHA, Rizal H, Said MA, Myint PK, Su TT

Int J Environ Res Public Health, 2022 Jul 25;19(15).
PMID: 35897412 DOI: 10.3390/ijerph19159034

Increasing life expectancy has led to a global rise in late-life diseases. Quality of Life (QOL) is important for healthy life expectancy. The active ageing framework serves as a guide for policymakers to design policies that enhance the QOL of older people. This study aims to determine the association between awareness of active ageing and QOL. The Malay version of the 26-item WHOQOL-BREF questionnaire was utilised along with the 14-item Active Ageing Awareness Questionnaire (AAAQ). A total of 532 participants had a mean (SD) age of 50.2 (5.9), were largely ethnic Malay (96.2%), female (52.8%), and comprised largely of low-income households (65.4%). The median (IQR) AAAQ score was 71.4 (19.1). The hierarchical multiple regression analysis revealed significant positive association between AAAQ and the QOL domains of physical (β = 0.154, p < 0.001), psychological (β = 0.196, p < 0.001), social relationship (β = 0.175, p < 0.001), and environment (β = 0.145, p < 0.001) after adjusting for all covariates. Awareness of active ageing was found to have a positive effect on all domains of QOL among pre-elder employees, and thus, we recommend that policies to improve active ageing awareness should be implemented for healthy life expectancy in ageing populations.
Fulltext Pre-treatment of Oil Palm Biomass for Fermentable Sugars Production

Rizal NFAA, Ibrahim MF, Zakaria MR, Abd-Aziz S, Yee PL, Hassan MA

Molecules, 2018 Jun 07;23(6).
PMID: 29880760 DOI: 10.3390/molecules23061381

Malaysia is the second largest palm oil producer in the world and this industry generates more than 80 million tonnes of biomass every year. When considering the potential of this biomass to be used as a fermentation feedstock, many studies have been conducted to develop a complete process for sugar production. One of the essential processes is the pre-treatment to modify the lignocellulosic components by altering the structural arrangement and/or removing lignin component to expose the internal structure of cellulose and hemicellulose for cellulases to digest it into sugars. Each of the pre-treatment processes that were developed has their own advantages and disadvantages, which are reviewed in this study.
Fulltext The Effects of Brain Breaks on Motives of Participation in Physical Activity among Primary School Children in Malaysia

Hajar MS, Rizal H, Kueh YC, Muhamad AS, Kuan G

Int J Environ Res Public Health, 2019 Jul 02;16(13).
PMID: 31269644 DOI: 10.3390/ijerph16132331

Brain breaks is a physical activity (PA) video designed for school settings that is used to stimulate student's health and learning. The purpose of this study is to measure the effects of brain breaks on motives of participation in PA among primary school children in Malaysia. Purposive sampling was used to divide 159 male and 176 female students aged 10 to 11 years old, mean (standard deviation (SD)) = 10.51 (0.50), from two schools in Kelantan, Malaysia into intervention (n = 183) and control (n = 152) groups. Students undertook brain breaks activities on school days (five minutes per session) spread out for a period of four months. Mixed factorial analysis of variance (ANOVA) was used to test the students' motives of participation in PA for pre-, mid-, and post-tests using the Physical Activity and Leisure Motivation Scale-Youth-Malay (PALMS-Y-M). Mixed factorial ANOVA showed significant changes in enjoyment, F(2, 392) = 8.720, p-value (ηp2) = 0.001 (0.043); competitiveness, F(2, 195) = 4.364, p-value (ηp2) = 0.014 (0.043); appearance, F(2, 392) = 5.709, p-value (ηp2) = 0.004 (0.028); and psychological condition, F(2, 392) = 4.376, p-value (ηp2) = 0.013 (0.022), whereas mastery, affiliation, and physical condition were not significant (p < 0.05). Further post-hoc analysis revealed a significant downward trend in the control group (p < 0.05). Brain breaks is successful in maintaining students' motives for PA in four of the seven factors.
Fulltext The Effects of Fixed Combination of Bimatoprost-Timolol and Travoprost-Timolol on Intraocular Pressure in Patients With Primary Open-Angle Glaucoma or Ocular Hypertension, Previously on Nonfixed Combination of Latanoprost and Timolol

Lee MY, Teh NC, Nur Zulekha M, Thayanithi S, Jelinar MN, Rizal AM, et al.

Asia Pac J Ophthalmol (Phila), 2012;1(4):208-12.
PMID: 26107474 DOI: 10.1097/APO.0b013e31825c5b1b

PURPOSE: To compare the effects of fixed combination of bimatoprost-timolol and travoprost-timolol on intraocular pressure (IOP) in patients with primary open-angle glaucoma or ocular hypertension.
DESIGN: This was a prospective, randomized, observer-masked, crossover parallel comparison trial.
METHODS: Forty-one patients with primary open-angle glaucoma or ocular hypertension on nonfixed combination of latanoprost and timolol with IOP of 21 mm Hg or less were randomized to either bimatoprost-timolol or travoprost-timolol fixed combinations for 8-week treatment period. Intraocular pressure was measured at 8 AM, 12 PM, 4 PM, and 8 PM at the baseline and at the end point. Conjunctiva hyperemia and superficial punctate keratopathy after treatment with each fixed combination therapy were assessed and compared with the baseline. Patients were then switched to the opposite drug without a medication-free period for another 8-week, and diurnal IOP measurement was repeated.
RESULTS: Bimatoprost-timolol fixed combination reduced the baseline mean diurnal IOP statistically significantly from 17.3 mm Hg [95% confidence interval (CI), 16.8-17.7 mm Hg] to 16.4 mm Hg (95% CI, 15.9-17.0 mm Hg) (P = 0.036). Travoprost-timolol fixed combination lowered the mean diurnal IOP to 17.1 mm Hg (95% CI, 16.5-17.7 mm Hg), but it was not significant. Direct comparison between the 2 fixed combinations showed no significant difference. Both fixed combinations had no significant effect on conjunctiva hyperemia. Interestingly, patients on travoprost-timolol fixed combination had significantly less superficial punctuate keratopathy (P = 0.012).
CONCLUSIONS: Both fixed combination of bimatoprost-timolol and travoprost-timolol had no significantly different ocular hypotensive effect. However, bimatoprost-timolol fixed combination produced additional IOP lowering in patients previously treated with nonfixed combination of latanoprost and timolol.
Fulltext Freshwater fishes (Actinopterygii) of Kenyir Reservoir, Peninsular Malaysia: Updated checklist, taxonomic concerns and alien species

Aqmal-Naser M, Ali NA, Azmi NU, Fahmi-Ahmad M, Rizal SA, Ahmad AB

Biodivers Data J, 2023;11:e100337.
PMID: 38327369 DOI: 10.3897/BDJ.11.e100337

BACKGROUND: A total of 87 freshwater fish species from 30 families were recorded from the Kenyir Reservoir, Peninsular Malaysia, where 75 are native and 12 are introduced species. Few species still have unstable taxonomy identities which urge further studies. Most of the species were categorised as Least Concern (LC) and two were threatened species; Endangered and Critically Endangered (EN and CR). One introduced species, Gambusiaaffinis is widespread in the human-associated area, while other introduced fish species can be considered low in numbers.
NEW INFORMATION: Twenty five fish species are recorded for the first time in the Kenyir Reservoir.
Fulltext Development of the Active Ageing Awareness Questionnaire in Malaysia

Ahmad Bahuri NH, Rizal H, Abdul Majid H, Said MA, Su TT

Healthcare (Basel), 2021 Apr 22;9(5).
PMID: 33922206 DOI: 10.3390/healthcare9050499

The world's ageing population is associated with increased morbidity, disability, and social and financial insecurity, which may affect quality of life (QoL). Therefore, the World Health Organization (WHO) endorsed the Active Ageing Framework (AAF) in 2002 to enhance QoL as people age. However, little is known about the status of awareness of active ageing among the population, and there is no appropriate tool for assessment. Hence, the Awareness of Active Ageing Questionnaire (AAAQ) was developed. The content, linguistic and face validations together with test-retest reliability were conducted. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed to test the structural validity of the AAAQ. A total of 110 participants (mean ± SD = 50.19 ± 5.52) were selected for the pilot, 81 participants (mean ± SD = 49.40 ± 5.70) for the test-retest, and 404 participants (mean ± SD = 49.90 ± 5.80) for CFA and EFA tests. The 16-item AAAQ Malay version showed satisfactory reliability and validity. The Cronbach's alpha was more than 0.7 and showed good fit: Cmin/df = 2.771, GFI = 0.903, TLI = 0.951, RMSEA = 0.08. The AAAQ is suitable for measuring the awareness of active ageing among the middle-aged population in Malaysia.
Fulltext An improved method to detect arrhythmia using ensemble learning-based model in multi lead electrocardiogram (ECG)

Mandala S, Rizal A, Adiwijaya, Nurmaini S, Suci Amini S, Almayda Sudarisman G, et al.

PLoS One, 2024;19(4):e0297551.
PMID: 38593145 DOI: 10.1371/journal.pone.0297551

Arrhythmia is a life-threatening cardiac condition characterized by irregular heart rhythm. Early and accurate detection is crucial for effective treatment. However, single-lead electrocardiogram (ECG) methods have limited sensitivity and specificity. This study propose an improved ensemble learning approach for arrhythmia detection using multi-lead ECG data. Proposed method, based on a boosting algorithm, namely Fine Tuned Boosting (FTBO) model detects multiple arrhythmia classes. For the feature extraction, introduce a new technique that utilizes a sliding window with a window size of 5 R-peaks. This study compared it with other models, including bagging and stacking, and assessed the impact of parameter tuning. Rigorous experiments on the MIT-BIH arrhythmia database focused on Premature Ventricular Contraction (PVC), Atrial Premature Contraction (PAC), and Atrial Fibrillation (AF) have been performed. The results showed that the proposed method achieved high sensitivity, specificity, and accuracy for all three classes of arrhythmia. It accurately detected Atrial Fibrillation (AF) with 100% sensitivity and specificity. For Premature Ventricular Contraction (PVC) detection, it achieved 99% sensitivity and specificity in both leads. Similarly, for Atrial Premature Contraction (PAC) detection, proposed method achieved almost 96% sensitivity and specificity in both leads. The proposed method shows great potential for early arrhythmia detection using multi-lead ECG data.
Fulltext Confirmatory Factor Analysis of the Malay-Language Transtheoretical Model of Physical Activity among Malaysian Primary School Children

Rizal H, Hajar MS, Kueh YC, Muhamad AS, Kuan G

Malays J Med Sci, 2019 Mar;26(2):99-113.
PMID: 31447613 MyJurnal DOI: 10.21315/mjms2019.26.2.11

Introduction: The transtheoretical model (TTM) is an integrative model of intentional change consisting of stages of change, processes of change, decisional balance and self-efficacy. This study aimed at validating the TTM questionnaires on physical activity for Malaysian children using confirmatory factor analysis.
Methods: The participants were 381 Malay students (188 male; 193 female), aged 10-12 years old, with a mean age of 10.94 (SD = 0.81). The original version of the TTM was translated into the Malay language using forward and backward translation. Certain phrases were adapted based on the local culture and vocabulary suitable for primary school students.
Results: The final measurement models and their fit indices were: processes of change (CFI = 0.939, TLI = 0.925, SRMR = 0.040, RMSEA = 0.030); decisional balance (CFI = 0.897, TLI = 0.864, SRMR = 0.045, RMSEA = 0.038); and self-efficacy (CFI = 0.934, TLI = 0.915, SRMR = 0.042, RMSEA = 0.032).
Conclusion: Care must be taken when using the TTM with children, as it has been prevalently validated with adults. The final version of the TTM questionnaire for Malay primary school children had 24 items for process of changes, 13 items for self-efficacy and 10 items for decisional balance.
Thoraco-laparotomy approach to salvage a life-threatening cardiac box stab injury to the infecrior vena cava in Malaysia: a case report

Mahadi IA, Tan JH, Teh JZ, Mohamad Y, Rizal IA

J Trauma Inj, 2023 Sep;36(3):286-289.
PMID: 39381707 DOI: 10.20408/jti.2022.0071

Torso stab injuries near the cardiac box may present unique challenges due to difficulties in hemorrhage control. For a stab injury to the heart, the repair is straightforwardly performed via median sternotomy. In contrast, injuries to the inferior vena cava are challenging to repair, especially when they are close to the diaphragm, and the bleeding can be torrential. Herein, we describe a case of a self-inflicted stab wound within the "cardiac box." The trajectory of the stab injuries went below the diaphragm and injured the infradiaphragmatic inferior vena cava. Successful emergent repair via the thoraco-laparotomy approach revived the young man. In this report, we revisit and discuss previous large series of patients with this rare vena cava injury.
cagA gene variants in Malaysian Helicobacter pylori strains isolated from patients of different ethnic groups

Ramelah M, Aminuddin A, Alfizah H, Isa MR, Jasmi AY, Tan HJ, et al.

FEMS Immunol. Med. Microbiol., 2005 May 1;44(2):239-42.
PMID: 15866222

Helicobacter pylori infection of a distinct subtype of cagA may lead to different pathological manifestation. The aim of this study is to determine the presence of cagA gene and its variants in H. pylori infection among different ethnic groups and its effect on gastroduodenal diseases. Overall detection of cagA among the 205 clinical isolates of H. pylori was 94%. Variations in size of the 3' region of cagA gene were examined among 192 Malaysian H. pylori cagA-positive strains. Results showed that three cagA variants differing in fragment length of PCR products were detected and designated as type A (621-651bp), type B (732-735bp) and type C (525 bp). Although there was no association between any of the cagA subtypes with peptic ulcer disease (p>0.05), an association between cagA subtypes with a specific ethnic group was observed. Specific-cagA subtype A strains were predominantly isolated from Chinese compared to Malays and Indians (p<0.0005), and cagA subtype B strains were predominantly isolated from Malays and Indians compared to Chinese (p<0.05). The cagA type A strains of H. pylori is commonly found in the Chinese patients who have a higher risk of peptic ulcer disease, thus indicating that it could be used as an important clinical biomarker for a more severe infection.
Fulltext Unexpected complication of arteriovenous fistula of the left common carotid to internal jugular vein following central venous catheterization

Henry TCL, Huei TJ, Yuzaidi M, Safri LS, Krishna K, Rizal IA, et al.

Chin J Traumatol, 2020 Feb;23(1):29-31.
PMID: 31744657 DOI: 10.1016/j.cjtee.2019.10.001

Incidence of inadvertent arterial puncture secondary to central venous catheter insertion is not common with an arterial puncture rate of <1%. This is due to the advancements and wide availability of ultrasound to guide its insertion. Formation of arteriovenous fistula after arterial puncture is an unexpected complication. Till date, only five cases (including this case) of acquired arteriovenous fistula formation has been described due to inadvertent common carotid puncture. The present case is a 26-year-old man sustained traumatic brain injuries, chest injuries and multiple bony fractures. During resuscitative phase, attempts at left central venous catheter via left internal jugular vein under ultrasound guidance resulted in inadvertent puncture into the left common carotid artery. Surgical neck exploration revealed that the catheter had punctured through the left internal jugular vein into the common carotid artery with formation of arteriovenous fistula. The catheter was removed successfully and common carotid artery was repaired. Postoperatively, the patient recovered and clinic visits revealed no neurological deficits. From our literature review, the safest method for removal is via endovascular and open surgical removal. The pull/push technique (direct removal with compression) is not recommended due to the high risk for stroke, bleeding and hematoma formation.
Evaluation of the thermomechanical properties and biodegradation of brown rice starch-based chitosan biodegradable composite films

Hasan M, Gopakumar DA, Olaiya NG, Zarlaida F, Alfian A, Aprinasari C, et al.

Int J Biol Macromol, 2020 Aug 01;156:896-905.
PMID: 32289410 DOI: 10.1016/j.ijbiomac.2020.04.039

Biodegradable films composed of starch and chitosan plasticized by palm oil were fabricated via a solvent casting technique. In this study, the influence of the ratio of brown rice starch and chitosan on the mechanical, thermal, antimicrobial, and morphological properties of the films was investigated. Antimicrobial films with a smooth surface and a compact structure of brown rice starch were obtained. The results showed that a higher proportion of chitosan in the polymer blends resulted in a substantial enhancement in the tensile strength (TS) and thermal stability of the film. The TS values for BRS100, BRS30CH70, BRS50CH50, BRS70CH30, and CH100 were 3.7, 15.2, 10.2, 9.3, and 8.8 MPa, respectively, and the elongation at break (EB) values of the BRS100, BRS30CH70, BRS50CH50, BRS70CH30, and CH100 samples were 39.5%, 34.7%, 7.3%, 11.5%, and 6.9%, respectively. The addition of chitosan to the brown rice starch samples resulted in a reduced water uptake of the film. The film with a balanced ratio of brown rice starch and chitosan exhibited excellent water resistance, with its water absorption being the lowest among all of the studied compositions.
Fulltext Functional Properties of Antimicrobial Neem Leaves Extract Based Macroalgae Biofilms for Potential Use as Active Dry Packaging Applications

Oyekanmi AA, Kumar USU, H P S AK, Olaiya NG, Amirul AA, Rahman AA, et al.

Polymers (Basel), 2021 May 20;13(10).
PMID: 34065404 DOI: 10.3390/polym13101664

Antimicrobial irradiated seaweed-neem biocomposite films were synthesized in this study. The storage functional properties of the films were investigated. Characterization of the prepared films was conducted using SEM, FT-IR, contact angle, and antimicrobial test. The macroscopic and microscopic including the analysis of the functional group and the gas chromatography-mass spectrometry test revealed the main active constituents present in the neem extract, which was used an essential component of the fabricated films. Neem leaves' extracts with 5% w/w concentration were incorporated into the matrix of seaweed biopolymer and the seaweed-neem bio-composite film were irradiated with different dosages of gamma radiation (0.5, 1, 1.5, and 2 kGy). The tensile, thermal, and the antimicrobial properties of the films were studied. The results revealed that the irradiated films exhibited improved functional properties compared to the control film at 1.5 kGy radiation dosage. The tensile strength, tensile modulus, and toughness exhibited by the films increased, while the elongation of the irradiated bio-composite film decreased compared to the control film. The morphology of the irradiated films demonstrated a smoother surface compared to the control and provided surface intermolecular interaction of the neem-seaweed matrix. The film indicated an optimum storage stability under ambient conditions and demonstrated no significant changes in the visual appearance. However, an increase in the moisture content was exhibited by the film, and the hydrophobic properties was retained until nine months of the storage period. The study of the films antimicrobial activities against Staphylococcus aureus (SA), and Bacillus subtilis (BS) indicated improved resistance to bacterial activities after the incorporation of neem leaves extract and gamma irradiation. The fabricated irradiated seaweed-neem bio-composite film could be used as an excellent sustainable packaging material due to its effective storage stability.
Fulltext Bionanocarbon Functional Material Characterisation and Enhancement Properties in Nonwoven Kenaf Fibre Nanocomposites

Rizal S, Mistar EM, Rahman AA, H P S AK, Oyekanmi AA, Olaiya NG, et al.

Polymers (Basel), 2021 Jul 14;13(14).
PMID: 34301059 DOI: 10.3390/polym13142303

Bionanocarbon as a properties enhancement material in fibre reinforced nanobiocomposite was investigated for sustainable material applications. Currently, an extensive study using the micro size of biocarbon as filler or reinforcement materials has been done. However, poor fibre-matrix interface results in poor mechanical, physical, and thermal properties of the composite. Hence in this study, the nanoparticle of biocarbon was synthesised and applied as a functional material and properties enhancement in composite material. The bionanocarbon was prepared from an oil palm shell, an agriculture waste precursor, via a single-step activation technique. The nanocarbon filler loading was varied from 0, 1, 3, and 5% as nanoparticle properties enhancement in nonwoven kenaf fibre reinforcement in vinyl ester composite using resin transfer moulding technique. The functional properties were evaluated using TEM, particle size, zeta potential, and energy dispersion X-ray (EDX) elemental analysis. While the composite properties enhancement was evaluated using physical, mechanical, morphological, thermal, and wettability properties. The result indicated excellent nanofiller enhancement of fibre-matrix bonding that significantly improved the physical, mechanical, and thermal properties of the bionanocomposite. The SEM morphology study confirmed the uniform dispersion of the nanoparticle enhanced the fibre-matrix interaction. In this present work, the functional properties of bionanocarbon from oil palm shells (oil palm industrial waste) was incorporated in nanaobiocomposite, which significantly enhance its properties. The optimum enhancement of the bionanocomposite functional properties was obtained at 3% bionanocarbon loading. The improvement can be attributed to homogeneity and improved interfacial interaction between nanoparticles, kenaf fibre, and matrix.
Fulltext Propionic Anhydride Modification of Cellulosic Kenaf Fibre Enhancement with Bionanocarbon in Nanobiocomposites

Rizal S, Mistar EM, Oyekanmi AA, H P S AK, Alfatah T, Olaiya NG, et al.

Molecules, 2021 Jul 13;26(14).
PMID: 34299524 DOI: 10.3390/molecules26144248

The use of chemical modification of cellulosic fibre is applied in order to increase the hydrophobicity, hence improving the compatibility between the fibre and matrix bonding. In this study, the effect of propionic anhydride modification of kenaf fibre was investigated to determine the role of bionanocarbon from oil palm shell agricultural wastes in the improvement of the functional properties of bionanocomposites. The vinyl esters reinforced with unmodified and propionic anhydride modified kenaf fibres bio nanocomposites were prepared using 0, 1, 3, 5 wt% of bio-nanocarbon. Characterisation of the fabricated bionanocomposite was carried out using FESEM, TEM, FT-IR and TGA to investigate the morphological analysis, surface properties, functional and thermal analyses, respectively. Mechanical performance of bionanocomposites was evaluated according to standard methods. The chemical modification of cellulosic fibre with the incorporation of bionanocarbon in the matrix exhibited high enhancement of the tensile, flexural, and impact strengths, for approximately 63.91%, 49.61% and 54.82%, respectively. The morphological, structural and functional analyses revealed that better compatibility of the modified fibre-matrix interaction was achieved at 3% bionanocarbon loading, which indicated improved properties of the bionanocomposite. The nanocomposites exhibited high degradation temperature which signified good thermal stability properties. The improved properties of the bionanocomposite were attributed to the effect of the surface modification and bionanocarbon enhancement of the fibre-matrix networks.
On the taxonomy and phylogeny of the skinks Lipinia sekayuensis Grismer, Ismail, Awang, Rizal, & Ahmad and Lipinia surda Boulenger from Peninsular Malaysia

Grismer LL, Wood PL, Syafiq MF, Badli-Sham BH, Rizal SA, Ahmad AB, et al.

Zootaxa, 2016 Aug 02;4147(1):59-66.
PMID: 27515603 DOI: 10.11646/zootaxa.4147.1.3

An integrative taxonomic analysis based on additional specimens and color photographs of Lipinia sekayuensis and additional color photographs of L. surda from Pulau Tioman and the Gunung Panti Forest Reserve, Peninsular Malaysia confirm the previous hypotheses that L. sekayuensis is a valid species and is the sister species of L. surda. The two species share a 12.8% sequence divergence between them.
Two new Tytthoscincus Linkem, Diesmos, Brown (Squamata; Scincidae) from Peninsular Malaysia and another case of microsyntopy between ecologically specialized, unrelated, leaf-litter species

Grismer LL, Wood PLJ, Ahmad AB, Baizul-Hafsyam BS, Afiq-Shuhaimi M, Rizal SA, et al.

Zootaxa, 2018 May 29;4425(1):87-107.
PMID: 30313468 DOI: 10.11646/zootaxa.4425.1.5

Two new species of diminutive, sympatric, lowland, leaf-litter skinks of the genus Tytthoscincus Linkem, Diesmos Brown from the Sekayu region of Hulu Terengganu, Terengganu State in northeastern Peninsular Malaysia are described on the basis genetic and morphological data. One of the new species, T. monticolus sp. nov., was collected in a hilly riparian area along Sungai (=river) Bubu and is most closely related to an undescribed species from the Tembak Reservoir area. The other, T. keciktuek sp. nov. collected along Sungai Peres, is most closely related to T. perhentianensis Grismer, Wood, Grismer from Pulau (=island) Perhentian Besar. Sympatry and syntopy of multiple, specialized, unrelated, leaf-litter species of Tytthoscincus was previously only known from upland areas and these new species represent the first example of lowland of sympatry. More importantly, however, these endemic species add to a growing body of research and discoveries that continue to underscore the unrealized biodiversity of the riparian systems of Hulu Terengganu and the Sekayu region and their need for protection and continued study.
Fulltext Properties and Characterization of a PLA-Chitin-Starch Biodegradable Polymer Composite

Olaiya NG, Surya I, Oke PK, Rizal S, Sadiku ER, Ray SS, et al.

Polymers (Basel), 2019 Oct 11;11(10).
PMID: 31614623 DOI: 10.3390/polym11101656

This paper presents a comparison on the effects of blending chitin and/or starch with poly(lactic acid) (PLA). Three sets of composites (PLA-chitin, PLA-starch and PLA-chitin-starch) with 92%, 94%, 96% and 98% PLA by weight were prepared. The percentage weight (wt.%) amount of the chitin and starch incorporated ranges from 2% to 8%. The mechanical, dynamic mechanical, thermal and microstructural properties were analyzed. The results from the tensile strength, yield strength, Young's modulus, and impact showed that the PLA-chitin-starch blend has the best mechanical properties compared to PLA-chitin and PLA-starch blends. The dynamic mechanical analysis result shows a better damping property for PLA-chitin than PLA-chitin-starch and PLA-starch. On the other hand, the thermal property analysis from thermogravimetry analysis (TGA) shows no significant improvement in a specific order, but the glass transition temperature of the composite increased compared to that of neat PLA. However, the degradation process was found to start with PLA-chitin for all composites, which suggests an improvement in PLA degradation. Significantly, the morphological analysis revealed a uniform mix with an obvious blend network in the three composites. Interestingly, the network was more significant in the PLA-chitin-starch blend, which may be responsible for its significantly enhanced mechanical properties compared with PLA-chitin and PLA-starch samples.

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links