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Box-Behnken supported development and validation of robust HPTLC method: an application in estimation of punarnavine in leaf, stem, and their callus of Boerhavia diffusa Linn

Ahmad W, Husain I, Ahmad N, Amir M, Sarafroz M, Ansari MA, et al.

3 Biotech, 2020 Apr;10(4):165.
PMID: 32206499 DOI: 10.1007/s13205-020-2154-1

Boerhavia diffusa (BD) Linn. (Nyctaginaceae) is one of the most commonly used herbs in the Indian traditional system of medicine for the urinary disorders. The aim of the current investigation was to carry out initiation, development, and maintenance of BD callus cultures and quantitative estimation of punarnavine in plant and callus extracts. Leaves and stem of BD were used as explant for the tissue culture studies using Murashige and Skoog (MS) basal medium. MS Media comprising 2,4-Dichlorophenoxy acetic acid (2,4-D) (1 ppm) and 2,4-D (1 ppm) + Indole-3-acetic acid (IAA) (1.0 ppm) were found to yield friable callus from leaf explant; similarly, 2,4-D (0.3 ppm) + IAA (0.75 ppm) + Kinetin (0.3 ppm) and 2,4-D (0.5 ppm) + Naphthalene acetic acid (NAA) (1.5 ppm) + Kinetin (0.3 ppm) were found to yield friable callus from the stem explant. High-performance thin-layer chromatography method was been developed for the quantitative estimation of punarnavine (Rf = 0.73) using mobile phase containing toluene: ethyl acetate: formic acid in the ratio (7.0:2.5:0.7, v/v/v) at 262 nm. The validated method was found linear (r2 = 0.9971) in a wide range (100-1000 ng spot-1), precise, accurate, and robust. The values of limit of detection, LOD = 30.3 ng spot-1, and limit of quantification, LOQ = 100.0 ng spot-1. The robustness of the method was proved by applying the Box-Behnken design (BBD). The developed method found appropriate for the quality control of medicinal plants containing punarnavine as a constituent.
Fulltext Improving knowledge of doctors and paramedics through effective bone procurement workshop: A cognitive approach

Mohd S, Yusof N, Lai LL, Hossain MG, Ramalingam S, Hamid SSA, et al.

BMC Med Educ, 2019 Jul 01;19(1):238.
PMID: 31262281 DOI: 10.1186/s12909-019-1685-9

BACKGROUND: Procurement of bone allograft must be performed by trained personnel. Improper handling and lack of knowledge during bone procurement will lead to contamination hence jeopardizing quality of the procured bones and expose bone recipients to risks of infection in post-operative phase. Bone procurement workshop is the fundamental training programme to enhance skill among personnel who has been or will be involved in bone procurement. This study evaluated the effectiveness of the workshop contents including teaching materials by assessing the knowledge on bone procurement among the participants before and after the workshop.
METHODS: Bone procurement workshop was held for 2 days for doctors and paramedics. The knowledge on bone procurement was evaluated in pre- and post-assessments by answering self administration questionnaire before and after the workshop, respectively.
RESULTS: A total of 50 participants comprised of doctors and paramedics attended the workshop however only 15 (55.6%) doctors and 12 (44.4%) paramedics completed the assessments. Overall, the mean total score for the post-assessment (61.4%) was significantly higher (p
Fulltext Metamaterial Cell-Based Superstrate towards Bandwidth and Gain Enhancement of Quad-Band CPW-Fed Antenna for Wireless Applications

Al-Bawri SS, Islam MS, Wong HY, Jamlos MF, Narbudowicz A, Jusoh M, et al.

Sensors (Basel), 2020 Jan 14;20(2).
PMID: 31947533 DOI: 10.3390/s20020457

A multiband coplanar waveguide (CPW)-fed antenna loaded with metamaterial unit cell for GSM900, WLAN, LTE-A, and 5G Wi-Fi applications is presented in this paper. The proposed metamaterial structure is a combination of various symmetric split-ring resonators (SSRR) and its characteristics were investigated for two major axes directions at (x and y-axis) wave propagation through the material. For x-axis wave propagation, it indicates a wide range of negative refractive index in the frequency span of 2-8.5 GHz. For y-axis wave propagation, it shows more than 2 GHz bandwidth of near-zero refractive index (NZRI) property. Two categories of the proposed metamaterial plane were applied to enhance the bandwidth and gain. The measured reflection coefficient (S11) demonstrated significant bandwidths increase at the upper bands by 4.92-6.49 GHz and 3.251-4.324 GHz, considered as a rise of 71.4% and 168%, respectively, against the proposed antenna without using metamaterial. Besides being high bandwidth achieving, the proposed antenna radiates bi-directionally with 95% as the maximum radiation efficiency. Moreover, the maximum measured gain reaches 6.74 dBi by a 92.57% improvement compared with the antenna without using metamaterial. The simulation and measurement results of the proposed antenna show good agreement.
Fulltext Norovirus outbreak among students of a boarding school in Kluang, Johor, Malaysia

Subahir MN, Jeffree MS, Hassan MR, Razak MFA, Mohamad SNG, Fong SY, et al.

J Infect Dev Ctries, 2019 04 30;13(4):274-277.
PMID: 32045370 DOI: 10.3855/jidc.11199

INTRODUCTION: Norovirus (NoV) is a contagious virus causing acute gastroenteritis and is mainly responsible for diarrheal outbreak in closed settings. The aims of this study were to describe the epidemiological characteristic of an outbreak in a boarding school, to assess the extent of the outbreak and to implement appropriate control measures.
METHODOLOGY: A descriptive study was conducted to describe the epidemiological characteristics of the outbreak. Data on demographic details, onset of abdominal symptoms, food intake history and contact with ill person three days prior to illness were obtained.
RESULTS: Twelve fresh stool and 14 food samples were tested for NoV and enteric pathogens, respectively. Out of 745 students, 42 (5.6%) were infected during this outbreak. Predominant clinical features were diarrhea (76.1%), vomiting (71.4%) and abdominal pain (67%). Eight (67%) stool samples and six (43.9%)food samples were positive for NoV and total coliforms, respectively. The dissemination of the disease was due to poor hygiene practices among students. Quarantine was imposed until the last case on September 28, 2016. The outbreak was declared over on September 30, 2016.
CONCLUSIONS: A NoV outbreak was determined first time in Malaysia. Environmental assessment showed poor hygienic conditions in the school's kitchen. The number of infected students increased considerably despite the implementation of preventive and control measures. Quarantine was effective to stop the outbreak which is characteristics of NoV outbreak.
Fulltext Development of generic Asian pelvic bone models using CT-based 3D statistical modelling

Ahrend MD, Noser H, Shanmugam R, Burr F, Kamer L, Kamarul T, et al.

J Orthop Translat, 2020 Jan;20:100-106.
PMID: 31908940 DOI: 10.1016/j.jot.2019.10.004

Background/Objective: Artificial bone models (ABMs) are used in orthopaedics for research of biomechanics, development of implants and educational purposes. Most of the commercially available ABMs approximate the morphology of Europeans, but they may not depict the Asian anatomy. Therefore, our aim was to develop the first Asian ABM of the pelvis and compare it with the existing pelvic ABM (Synbone®; Caucasian male).
Methods: One hundred clinical computed tomography (CTs) of adult pelvises (male n = 50, female n = 50) of Malay, Chinese and Indian descent were acquired. CTs were segmented and defined landmarks were placed. Three 3D statistical pelvic model and mean models (overall, male, female) were generated. Anatomical variations were analysed using principal component analysis. To measure gender-related differences and differences to the existing ABM, distances between the anterior superior iliac spines (ASIS), the anterior inferior iliac spines (AIIS), the promontory and the symphysis (conjugate vera, CV) as well as the ischial spines (diameter transversa, DT) were quantified.
Results: Principal component analysis displayed large variability regarding the pelvic shape and size. Female and male statistical models were similar in ASIS (225 ± 20; 227 ± 13 mm; P = 0.4153) and AIIS (185 ± 11; 187 ± 10 mm; P = 0.3982) and differed in CV (116 ± 10; 105 ± 10 mm; P
Fulltext Draft genome sequencing data of a pathogenic Pantoea stewartii subspecies stewartii strain SQT1 causing bronzing disease of jackfruit in Malaysia

Ibrahim R, Ismail-Suhaimy NW, Shu-Qing T, Ismail SI, Ina-Salwany MY, Yusof MT, et al.

Data Brief, 2020 Jun;30:105634.
PMID: 32395592 DOI: 10.1016/j.dib.2020.105634

A Gram-negative bacterium, Pantoea stewartii subspecies stewartii (P. stewartii subsp. stewartii) has been recognized as the causative agent for jackfruit bronzing disease in Malaysia. Here, we report the whole genome sequencing dataset of P. stewartii subsp. stewartii strain SQT1 isolated from local infected jackfruit. The paired-end libraries with an insert size of 350 bp was subjected to the Illumina Hiseq 4000, generating a genome size of 4,783,993 bp with a G+C content of 53.7%. A total protein of 4,671 was identified including virulence factors, resistance factors and secretion systems. Pantoea stewartii subsp. stewartii strain DC283 (NCBI accession no. CP017581.1) was used as a reference genome, where the query hit 72% coverage and average sequencing depth of 68. In total, 28,717 nucleotide polymorphisms, 520 small insertion/deletions and 142 structure variants were identified. The complete genome was deposited at the European Nucleotide Archive under the sample accession number ERP119356 and study accession number PRJEB36196.
An efficient biosorption-based dispersive liquid-liquid microextraction with extractant removal by magnetic nanoparticles for quantification of bisphenol A in water samples by gas chromatography-mass spectrometry detection

Subuhi NEAM, Saad SM, Zain NNM, Lim V, Miskam M, Kamaruzaman S, et al.

J Sep Sci, 2020 Aug;43(16):3294-3303.
PMID: 32519432 DOI: 10.1002/jssc.201901194

In this work, a simple, fast, sensitive, and environmentally friendly method was developed for preconcentration and quantitative measurement of bisphenol A in water samples using gas chromatography with mass spectrometry. The preconcentration approach, namely biosorption-based dispersive liquid-liquid microextraction with extractant removal by magnetic nanoparticles was performed based on the formation of microdroplet of rhamnolipid biosurfactant throughout the aqueous samples, which accelerates the mass transfer process between the extraction solvent and sample solution. The process is then followed by the application of magnetic nanoparticles for easy retrieval of the analyte-containing extraction solvent. Several important variables were optimized comprehensively including type of disperser solvent and desorption solvent, rhamnolipid concentration, volume of disperser solvent, amount of magnetic nanoparticles, extraction time, desorption time, ionic strength, and sample pH. Under the optimized microextraction and gas chromatography with mass spectrometry conditions, the method demonstrated good linearity over the range of 0.5-500 µg/L with a coefficient of determination of R2 = 0.9904, low limit of detection (0.15 µg/L) and limit of quantification (0.50 µg/L) of bisphenol A, good analyte recoveries (84-120%) and acceptable relative standard deviation (1.8-14.9%, n = 6). The proposed method was successfully applied to three environmental water samples, and bisphenol A was detected in all samples.
Fulltext Dataset on insightful bio-evaluation of 2-(quinoline-4-yloxy)acetamide analogues as potential anti-Mycobacterium tuberculosis catalase-peroxidase agents via in silico mechanisms

Oyebamiji AK, Josiah OM, Akintelu SA, Adeoye MD, Sabitu BO, Latona DF, et al.

Data Brief, 2021 Oct;38:107441.
PMID: 34692949 DOI: 10.1016/j.dib.2021.107441

The continuous havoc wrecked by tuberculosis among humans worldwide remains colossal. In this work, twenty-one (21) 2-(quinoline-4-yloxy)acetamide analogues were observed against Mycobacterium tuberculosis catalase-peroxidase (This enzyme shields bacteria from poisonous drug-like molecules) (PDB ID: 1sj2) using density functional theory method, QSAR study using material studio software and docking method via PyMol, AutoDock Tool, AutoDock Vina and Discovery studio 2017 as well as ADMET study via admetSAR2. Twelve descriptors were obtained from the optimized compounds which were used to develop valid QSAR model. More so, the binding affinity between 2-(quinoline-4-yloxy)acetamide analogues and Mycobacterium tuberculosis catalase-peroxidase (PDB ID: 1sj2) via docking method were reported. ADMET properties of some selected compounds were also examined.
Fulltext Classification of Breast Cancer Lesions in Ultrasound Images by Using Attention Layer and Loss Ensemble in Deep Convolutional Neural Networks

Kalafi EY, Jodeiri A, Setarehdan SK, Lin NW, Rahmat K, Taib NA, et al.

Diagnostics (Basel), 2021 Oct 09;11(10).
PMID: 34679557 DOI: 10.3390/diagnostics11101859

The reliable classification of benign and malignant lesions in breast ultrasound images can provide an effective and relatively low-cost method for the early diagnosis of breast cancer. The accuracy of the diagnosis is, however, highly dependent on the quality of the ultrasound systems and the experience of the users (radiologists). The use of deep convolutional neural network approaches has provided solutions for the efficient analysis of breast ultrasound images. In this study, we propose a new framework for the classification of breast cancer lesions with an attention module in a modified VGG16 architecture. The adopted attention mechanism enhances the feature discrimination between the background and targeted lesions in ultrasound. We also propose a new ensembled loss function, which is a combination of binary cross-entropy and the logarithm of the hyperbolic cosine loss, to improve the model discrepancy between classified lesions and their labels. This combined loss function optimizes the network more quickly. The proposed model outperformed other modified VGG16 architectures, with an accuracy of 93%, and also, the results are competitive with those of other state-of-the-art frameworks for the classification of breast cancer lesions. Our experimental results show that the choice of loss function is highly important and plays a key role in breast lesion classification tasks. Additionally, by adding an attention block, we could improve the performance of the model.
Fulltext Ethyl Cellulose and Hydroxypropyl Methyl Cellulose Blended Methotrexate-Loaded Transdermal Patches: In Vitro and Ex Vivo

Latif MS, Azad AK, Nawaz A, Rashid SA, Rahman MH, Al Omar SY, et al.

Polymers (Basel), 2021 Oct 09;13(20).
PMID: 34685214 DOI: 10.3390/polym13203455

Transdermal drug delivery systems (TDDSs) have become innovative, fascinating drug delivery methods intended for skin application to achieve systemic effects. TDDSs overcome the drawbacks associated with oral and parenteral routes of drug administration. The current investigation aimed to design, evaluate and optimize methotrexate (MTX)-loaded transdermal-type patches having ethyl cellulose (EC) and hydroxypropyl methyl cellulose (HPMC) at different concentrations for the local management of psoriasis. In vitro release and ex vivo permeation studies were carried out for the formulated patches. Various formulations (F1-F9) were developed using different concentrations of HPMC and EC. The F1 formulation having a 1:1 polymer concentration ratio served as the control formulation. ATR-FTIR analysis was performed to study drug-polymer interactions, and it was found that the drug and polymers were compatible with each other. The formulated patches were further investigated for their physicochemical parameters, in vitro release and ex vivo diffusion characteristics. Different parameters, such as surface pH, physical appearance, thickness, weight uniformity, percent moisture absorption, percent moisture loss, folding endurance, skin irritation, stability and drug content uniformity, were studied. From the hydrophilic mixture, it was observed that viscosity has a direct influence on drug release. Among all formulated patches, the F5 formulation exhibited 82.71% drug release in a sustained-release fashion and followed an anomalous non-Fickian diffusion. The permeation data of the F5 formulation exhibited about a 36.55% cumulative amount of percent drug permeated. The skin showed high retention for the F5 formulation (15.1%). The stability study indicated that all prepared formulations had very good stability for a period of 180 days. Therefore, it was concluded from the present study that methotrexate-loaded transdermal patches with EC and HPMC as polymers at different concentrations suit TDDSs ideally and improve patient compliance for the local management of psoriasis.
Fulltext Development and Relative Validity of a Semiquantitative Food Frequency Questionnaire to Estimate Dietary Intake among a Multi-Ethnic Population in the Malaysian Cohort Project

Shahar S, Shahril MR, Abdullah N, Borhanuddin B, Kamaruddin MA, Yusuf NAM, et al.

Nutrients, 2021 Apr 01;13(4).
PMID: 33915922 DOI: 10.3390/nu13041163

Measuring dietary intakes in a multi-ethnic and multicultural setting, such as Malaysia, remains a challenge due to its diversity. This study aims to develop and evaluate the relative validity of an interviewer-administered food frequency questionnaire (FFQ) in assessing the habitual dietary exposure of The Malaysian Cohort (TMC) participants. We developed a nutrient database (with 203 items) based on various food consumption tables, and 803 participants were involved in this study. The output of the FFQ was then validated against three-day 24-h dietary recalls (n = 64). We assessed the relative validity and its agreement using various methods, such as Spearman's correlation, weighed Kappa, intraclass correlation coefficient (ICC), and Bland-Altman analysis. Spearman's correlation coefficient ranged from 0.24 (vitamin C) to 0.46 (carbohydrate), and almost all nutrients had correlation coefficients above 0.3, except for vitamin C and sodium. Intraclass correlation coefficients ranged from -0.01 (calcium) to 0.59 (carbohydrates), and weighted Kappa exceeded 0.4 for 50% of nutrients. In short, TMC's FFQ appears to have good relative validity for the assessment of nutrient intake among its participants, as compared to the three-day 24-h dietary recalls. However, estimates for iron, vitamin A, and vitamin C should be interpreted with caution.
Study name: The Malaysian Cohort (TMC) project
Quorum sensing: a new prospect for the management of antimicrobial-resistant infectious diseases

Haque M, Islam S, Sheikh MA, Dhingra S, Uwambaye P, Labricciosa FM, et al.

Expert Rev Anti Infect Ther, 2021 05;19(5):571-586.
PMID: 33131352 DOI: 10.1080/14787210.2021.1843427

INTRODUCTION: Quorum-sensing (QS) is a microbial cell-to-cell communication system that utilizes small signaling molecules to mediates interactions between cross-kingdom microorganisms, including Gram-positive and -negative microbes. QS molecules include N-acyl-homoserine-lactones (AHLs), furanosyl borate, hydroxyl-palmitic acid methylester, and methyl-dodecanoic acid. These signaling molecules maintain the symbiotic relationship between a host and the healthy microbial flora and also control various microbial virulence factors. This manuscript has been developed based on published scientific papers.
AREAS COVERED: Furanones, glycosylated chemicals, heavy metals, and nanomaterials are considered QS inhibitors (QSIs) and are therefore capable of inhibiting the microbial QS system. QSIs are currently being considered as antimicrobial therapeutic options. Currently, the low speed at which new antimicrobial agents are being developed impairs the treatment of drug-resistant infections. Therefore, QSIs are currently being studied as potential interventions targeting QS-signaling molecules and quorum quenching (QQ) enzymes to reduce microbial virulence.
EXPERT OPINION: QSIs represent a novel opportunity to combat antimicrobial resistance (AMR). However, no clinical trials have been conducted thus far assessing their efficacy. With the recent advancements in technology and the development of well-designed clinical trials aimed at targeting various components of the, QS system, these agents will undoubtedly provide a useful alternative to treat infectious diseases.
Diagnosis of hearing deficiency using EEG based AEP signals: CWT and improved-VGG16 pipeline

Islam MN, Sulaiman N, Farid FA, Uddin J, Alyami SA, Rashid M, et al.

PeerJ Comput Sci, 2021;7:e638.
PMID: 34712786 DOI: 10.7717/peerj-cs.638

Hearing deficiency is the world's most common sensation of impairment and impedes human communication and learning. Early and precise hearing diagnosis using electroencephalogram (EEG) is referred to as the optimum strategy to deal with this issue. Among a wide range of EEG control signals, the most relevant modality for hearing loss diagnosis is auditory evoked potential (AEP) which is produced in the brain's cortex area through an auditory stimulus. This study aims to develop a robust intelligent auditory sensation system utilizing a pre-train deep learning framework by analyzing and evaluating the functional reliability of the hearing based on the AEP response. First, the raw AEP data is transformed into time-frequency images through the wavelet transformation. Then, lower-level functionality is eliminated using a pre-trained network. Here, an improved-VGG16 architecture has been designed based on removing some convolutional layers and adding new layers in the fully connected block. Subsequently, the higher levels of the neural network architecture are fine-tuned using the labelled time-frequency images. Finally, the proposed method's performance has been validated by a reputed publicly available AEP dataset, recorded from sixteen subjects when they have heard specific auditory stimuli in the left or right ear. The proposed method outperforms the state-of-art studies by improving the classification accuracy to 96.87% (from 57.375%), which indicates that the proposed improved-VGG16 architecture can significantly deal with AEP response in early hearing loss diagnosis.
Fulltext A cluster-randomized trial study on effectiveness of health education based intervention (HEBI) in improving flood disaster preparedness among community in Selangor, Malaysia: a study protocol

Mohd Tariq MN, Shahar HK, Baharudin MR, Ismail SNS, Manaf RA, Salmiah MS, et al.

BMC Public Health, 2021 09 24;21(1):1735.
PMID: 34560858 DOI: 10.1186/s12889-021-11719-3

BACKGROUND: Flood disaster preparedness among the community seldom received attention. Necessary intervention must be taken to prevent the problem. Health Education Based Intervention (HEBI) was developed following the Health Belief Model, particularly in improving flood disaster preparedness among the community. The main objective of this study is to assess the effect of HEBI on improving flood disaster preparedness among the community in Selangor. This study aims to develop, implement, and evaluate the impact of health education-based intervention (HEBI) based on knowledge, skills, and preparedness to improve flood disaster preparedness among the community in Selangor.
METHOD: A single-blind cluster randomized controlled trial will conduct at six districts in Selangor. Randomly selected respondents who fulfilled the inclusion criteria will be invited to participate in the study. Health education module based on Health Believed Theory will be delivered via health talks and videos coordinated by liaison officers. Data at three-time points at baseline, immediate, and 3 months post-intervention will be collected. A validated questionnaire will assess participants' background characteristics, knowledge, skill, and preparedness on disaster preparedness and perception towards disaster. Descriptive and inferential statistics will be applied for data analysis using IBM Statistical Package for Social Sciences version 25. Longitudinal correlated data on knowledge, skills, preparedness, and perception score at baseline, immediate post-intervention, and 6 months post-intervention will be analyzed using Generalized Estimating Equations (GEE).
DISCUSSION: It is expected that knowledge, skills, preparedness, and flood disaster perception score are more significant in the intervention group than the control group, indicating the Health Education Based Intervention (HEBI).
TRIAL REGISTRATION: Thai Clinical Trial TCTR20200202002 .
Improvement and screening of astaxanthin producing mutants of newly isolated Coelastrum sp. using ethyl methane sulfonate induced mutagenesis technique

Tharek A, Yahya A, Salleh MM, Jamaluddin H, Yoshizaki S, Hara H, et al.

Biotechnol Rep (Amst), 2021 Dec;32:e00673.
PMID: 34621628 DOI: 10.1016/j.btre.2021.e00673

Natural astaxanthin is known to be produced by green microalgae, a potent producer of the most powerful antioxidant. To increase the productivity of astaxanthin in microalgae, random mutagenesis has been extensively used to improve the yield of valuable substances. In the presented work, a newly isolated Coelastrum sp. was randomly mutagenized by exposure to ethyl methane sulfonate and further screened using two approaches; an approach for high growth mutant and an approach for high astaxanthin producing mutant with a high-throughput screening method using glufosinate. Among these, mutant G1-C1 that was selected using glufosinate showed the highest of total carotenoids (45.48±1.5 mg/L) and astaxanthin (28.32±2.5 mg/L) production, which was almost 2-fold higher than that of wild type. This study indicates that random mutagenesis via chemical mutation strategy and screening using glufosinate successfully expedited astaxanthin production in a mutated strain of a Coelastrum sp.
Enhanced Mechanical and Thermal Properties of Modified Oil Palm Fiber-Reinforced Polypropylene Composite via Multi-Objective Optimization of In Situ Silica Sol-Gel Synthesis

Mat Rozi N, Hamid HA, Hossain MS, Khalil NA, Ahmad Yahaya AN, Syimir Fizal AN, et al.

Polymers (Basel), 2021 Sep 29;13(19).
PMID: 34641152 DOI: 10.3390/polym13193338

A multi-objective optimization of in situ sol-gel process was conducted in preparing oil palm fiber-reinforced polypropylene (OPF-PP) composite for an enhancement of mechanical and thermal properties. Tetraethyl orthosilicate (TEOS) and butylamine were used as precursors and catalysts for the sol-gel process. The face-centered central composite design (FCCD) experiments coupled with response surface methodology (RSM) has been utilized to optimize in situ silica sol-gel process. The optimization process showed that the drying time after the in-situ silica sol-gel process was the most influential factor on silica content, while the molar ratio of TEOS to water gave the most significant effect on silica residue. The maximum silica content of 34.1% and the silica residue of 35.9% were achieved under optimum conditions of 21.3 h soaking time, 50 min drying time, pH value of 9.26, and 1:4 molar ratio of TEOS to water. The untreated oil palm fiber (OPF) and silica sol-gel modified OPF (SiO2-OPF) were used as the reinforcing fibers, with PP as a matrix and maleic anhydride grafted polypropylene (MAgPP) as a compatibilizer for the fiber-reinforced PP matrix (SiO2-OPF-PP-MAgPP) composites preparation. The mechanical and thermal properties of OPF-PP, SiO2-OPF-PP, SiO2-OPF-PP-MAgPP composites, and pure PP were determined. It was found that the OPF-S-PP-MAgPP composite had the highest toughness and stiffness with values of tensile strength, Young's modulus, and elongation at break of 30.9 MPa, 881.8 MPa, and 15.1%, respectively. The thermal properties analyses revealed that the OPF-S-PP-MAgPP exhibited the highest thermally stable inflection point at 477 °C as compared to pure PP and other composites formulations. The finding of the present study showed that the SiO2-OPF had the potential to use as a reinforcing agent to enhance the thermal-mechanical properties of the composites.
Physical, Mechanical, and Morphological Properties of Hybrid Cyrtostachys renda/Kenaf Fiber Reinforced with Multi-Walled Carbon Nanotubes (MWCNT)-Phenolic Composites

Loganathan TM, Hameed Sultan MT, Jawaid M, Ahsan Q, Naveen J, Shah AUM, et al.

Polymers (Basel), 2021 Oct 08;13(19).
PMID: 34641263 DOI: 10.3390/polym13193448

Adequate awareness of sustainable materials and eco-legislation have inspired researchers to identify alternative sustainable and green composites for synthetic fiber-reinforced polymer composites in the automotive and aircraft industries. This research focused on investigating the physical, mechanical, and morphological properties of different hybrid Cyrtostachys renda (CR)/kenaf fiber (K) (10C:0K, 7C:3K, 5C:5K, 3C:7K, 0C:10K) reinforced with 0.5 wt% MWCNT-phenolic composites. We incorporated 0.5 wt% of MWCNT into phenolic resin (powder) using a ball milling process for 25 h to achieve homogeneous distribution. The results revealed that CR fiber composites showed higher voids content (12.23%) than pure kenaf fiber composites (6.57%). CR fiber phenolic composite was more stable to the swelling tendency, resulting in the lowest percentage of swelling rate (4.11%) compared to kenaf composite (5.29%). The addition of kenaf fiber into CR composites had improved the tensile, flexural, and impact properties. The highest tensile and flexural properties were found for weight fraction of CR and kenaf fiber at 5C:5K (47.96 MPa) and 3C:7K (90.89 MPa) composites, respectively. In contrast, the highest impact properties were obtained for 0C:10K composites (9.56 kJ/m2). Based on the FE-SEM image, the CR fiber lumen was larger in comparison to kenaf fiber. The lumen of CR fiber was attributed to higher void and water absorption, lower mechanical properties compared to kenaf fiber. 5C:5K composite was selected as an optimal hybrid composite, based on the TOPSIS method. This hybrid composite can be used as an interior component (non-load-bearing structures) in the aviation and automotive sectors.
Waste NR Latex Based-Precursors as Carbon Source for CNTs Eco-Fabrications

Hazan MA, Chan KF, Jofri KA, Mamat MS, Endot NA, Liza S, et al.

Polymers (Basel), 2021 Oct 04;13(19).
PMID: 34641224 DOI: 10.3390/polym13193409

In this work, the potential of utilizing a waste latex-based precursor (i.e., natural rubber glove (NRG)) as a carbon source for carbon nanotube (CNT) fabrication via chemical vapor deposition has been demonstrated. Gas chromatography-mass spectroscopy (GC-MS) analysis reveals that the separation of the lightweight hydrocarbon chain from the heavier long chain differs in hydrocarbon contents in the NRG fraction (NRG-L). Both solid NRG (NRG-S) and NRG-L samples contain >63% carbon, <0.6% sulfur and <0.08% nitrogen content, respectively, as per carbon-nitrogen-sulfur (CNS) analysis. Growth of CNTs on the samples was confirmed by Raman spectra, SEM and TEM images, whereby it was shown that NRG-S is better than NRG-L in terms of synthesized CNTs yield percentage with similar quality. The optimum vaporization and reaction temperatures were 350 and 800 °C, respectively, considering the balance of good yield percentage (26.7%) and quality of CNTs (ID/IG = 0.84 ± 0.08, diameter ≈ 122 nm) produced. Thus, utilization of waste NRG as a candidate for carbon feedstock to produce value-added CNTs products could be a significant approach for eco-technology.
Fulltext Hypoxia-Induced Neuroinflammation in Alzheimer's Disease: Potential Neuroprotective Effects of Centella asiatica

Hambali A, Kumar J, Hashim NFM, Maniam S, Mehat MZ, Cheema MS, et al.

Front Physiol, 2021;12:712317.
PMID: 34721056 DOI: 10.3389/fphys.2021.712317

Alzheimer's disease (AD) is a neurodegenerative disorder that is characterised by the presence of extracellular beta-amyloid fibrillary plaques and intraneuronal neurofibrillary tau tangles in the brain. Recurring failures of drug candidates targeting these pathways have prompted research in AD multifactorial pathogenesis, including the role of neuroinflammation. Triggered by various factors, such as hypoxia, neuroinflammation is strongly linked to AD susceptibility and/or progression to dementia. Chronic hypoxia induces neuroinflammation by activating microglia, the resident immune cells in the brain, along with an increased in reactive oxygen species and pro-inflammatory cytokines, features that are common to many degenerative central nervous system (CNS) disorders. Hence, interests are emerging on therapeutic agents and plant derivatives for AD that target the hypoxia-neuroinflammation pathway. Centella asiatica is one of the natural products reported to show neuroprotective effects in various models of CNS diseases. Here, we review the complex hypoxia-induced neuroinflammation in the pathogenesis of AD and the potential application of Centella asiatica as a therapeutic agent in AD or dementia.
Fulltext Health management during COVID-19 pandemic-contribution of women health informaticians, medical physicists and veterinarians from Bangladesh and Malaysia during the world crisis

Yeong CH, Azhari HA, Parveen S, Juyena NS, Nahar N, Islam MA, et al.

Health Technol (Berl), 2021;11(5):1149-1163.
PMID: 34485010 DOI: 10.1007/s12553-021-00588-w

This article aims to highlight some of the contributions from Bangladeshi and Malaysian women scientists in the fields of health informatics, medical physics and biomedical engineering, and veterinary science in combating the COVID-19 world crisis. The status of COVID-19 situations in Bangladesh and Malaysia in respect to global scenario, some relevant government policies, lessons learnt from previous pandemics, socio-economic impacts of COVID-19, the impact on healthcare system and health management approaches taken by individual/institutional research group led by women scientists during the COVID-19 pandemic have been discussed and demonstrated in this article. These promising activities and initiatives will eventually motivate other women in science and extend their roles from laboratory to society in more aspects.

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