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Dynamic Mechanical Properties and Thermal Properties of Longitudinal Basalt/Woven Glass Fiber Reinforced Unsaturated Polyester Hybrid Composites

Haris NIN, Ilyas RA, Hassan MZ, Sapuan SM, Afdzaluddin A, Jamaludin KR, et al.

Polymers (Basel), 2021 Sep 29;13(19).
PMID: 34641159 DOI: 10.3390/polym13193343

This study investigates the mechanical, thermal, and chemical properties of basalt/woven glass fiber reinforced polymer (BGRP) hybrid polyester composites. The Fourier transform infrared spectroscopy (FTIR) was used to explore the chemical aspect, whereas the dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA) were performed to determine the mechanical and thermal properties. The dynamic mechanical properties were evaluated in terms of the storage modulus, loss modulus, and damping factor. The FTIR results showed that incorporating single and hybrid fibers in the matrix did not change the chemical properties. The DMA findings revealed that the B7.5/G22.5 composite with 7.5 wt% of basalt fiber (B) and 22.5 wt% of glass fiber (G) exhibited the highest elastic and viscous properties, as it exhibited the higher storage modulus (8.04 × 109 MPa) and loss modulus (1.32 × 109 MPa) compared to the other samples. All the reinforced composites had better damping behavior than the neat matrix, but no further enhancement was obtained upon hybridization. The analysis also revealed that the B22.5/G7.5 composite with 22.5 wt% of basalt fiber and 7.5 wt% of glass fiber had the highest Tg at 70.80 °C, and increased by 15 °C compared to the neat matrix. TMA data suggested that the reinforced composites had relatively low dimensional stabilities than the neat matrix, particularly between 50 to 80 °C. Overall, the hybridization of basalt and glass fibers in unsaturated polyester formed composites with higher mechanical and thermal properties than single reinforced composites.
Challenges in the Diagnosis of Beta-thalassemia Syndrome: The Importance of Molecular Diagnosis

Rameli N, Ramli M, Zulkafli Z, Hassan MN, Yusoff SM, Noor NHM, et al.

Oman Med J, 2022 Jan;37(1):e331.
PMID: 35136660 DOI: 10.5001/omj.2021.48

Patients with heterozygous β-thalassemia are generally asymptomatic. However, the intermediate phenotype is uncommon, and patients require further investigation to confirm the diagnosis. We describe a 32-year-old woman (gravida 3, para 2) with heterozygous β-thalassemia who presented with symptomatic anemia and had a history of frequent blood transfusion in each pregnancy. Physical examination was unremarkable. Laboratory results at presentation showed hypochromic microcytic anemia with reticulocytosis. Molecular study revealed intermedia phenotypes resulting from coinheritance of heterozygous β-globin chain mutation (IVS1-5) and a rare heterozygous α-globin triplication (αααanti-3.7). In this case report, we discuss the laboratory diagnostic approaches and the challenges faced in investigating this case.
Applicability of bio-synthesized nanoparticles in fungal secondary metabolites products and plant extracts for eliminating antibiotic-resistant bacteria risks in non-clinical environments

Kamaruzaman NH, Mohd Noor NN, Radin Mohamed RMS, Al-Gheethi A, Ponnusamy SK, Sharma A, et al.

Environ Res, 2022 Feb 03;209:112831.
PMID: 35123962 DOI: 10.1016/j.envres.2022.112831

The abundance of antibiotic-resistant bacteria in the prawn pond effluents can substantially impact the natural environment. The settlement ponds, which are the most common treatment method for farms wastewater, might effectively reduce the suspended solids and organic matter. However, the method is insufficient for bacterial inactivation. The current paper seeks to highlight the environmental issue associated with the distribution of antibiotic resistant bacteria (ARB) from prawn farm wastewater and their impact on the microbial complex community in the surface water which receiving these wastes. The inactivation of antibiotic-resistant bacteria in prawn wastewater is strongly recommended because the presence of antibiotic-resistant bacteria in the environment causes water pollution and public health issues. The nanoparticles are more efficient for bacterial inactivation. They are widely accepted due to their high chemical and mechanical stability, broad spectrum of radiation absorption, high catalytic activity, and high antimicrobial activity. Many studies have examined the use of fungi or plants extract to synthesis zinc oxide nanoparticles (ZnO NPs). It is evident from recent papers in the literature that green synthesized ZnO NPs from microbes and plant extracts are non-toxic and effective. ZnO NPs inactivate the bacterial cells as a function for releasing reactive oxygen species (ROS) and zinc ions. The inactivation of antibiotic-resistant bacteria tends to be more than 90% which exhibit strong antimicrobial behavior against bacterial species.
Self-perception of sexual harassment: A comparison between female medical and nursing students during clinical practice

Waryam Singh Malhi FSA, Sugathan S, Binti Azhar NAS, Binti Wan Roslan WIN, Abu Bakar HAB, Binti Zolkaine SM

Educ Health (Abingdon), 2021 12 24;34(2):55-63.
PMID: 34937299 DOI: 10.4103/1357-6283.332958

Background: Sexual harassment (SH) may occur anywhere in the world, including the hospital setting. Medical and nursing students are not excluded from being sexually harassed during their clinical practice. This study examined the experiences and compared the perception of SH between female medical and nursing students during their clinical practice in Perak, Malaysia.
Methods: A comparative cross-sectional study design was done among female medical and nursing students during their clinical practice.
Results: Total respondents were 481 female medical and nursing students (response rate of 96.2%). About 17.8% of medical and 18.8% of nursing students had been sexually harassed. The most common harasser for medical and nursing students were males (51.2% and 48.8%, respectively), patients (39.7% and 60.3%, respectively), age 30s (41.0% and 59.0%, respectively) and 40s (65.5% and 34.5%, respectively), occurred in medical wards for both groups (50% each). From the SH checklist, 76.9% of medical and 73.5% of nursing students had experienced at least one item of the total 18 items. The abnormal sexual desire of an individual was chosen as the reason for SH by 44.9% of medical and 33.8% of nursing students. The majority of respondents said the issue of SH in clinical practice was very serious. Around 32% of medical students choose the fear of being disadvantaged during clinical practice as the reason why the victims kept quiet while 41.5% of nursing students chose because of not having evidence. Both groups of students suggested establishing rules and laws relating to SH (30.8% and 35.5%, respectively) as effective methods to prevent it. About 75.3% of medical and 81.6% of nursing students agreed that it was very necessary for implementing a SH prevention program.
Discussion: Although SH is not a new issue, there is insufficient exposure about SH among medical and nursing students. This can be corrected by increasing their knowledge and awareness about SH.
Development and validation of pan-Leptospira Taqman qPCR for the detection of Leptospira spp. in clinical specimens

Mohd Ali MR, Mohd Safee AW, Ismail NH, Abu Sapian R, Mat Hussin H, Ismail N, et al.

Mol Cell Probes, 2018 04;38:1-6.
PMID: 29524642 DOI: 10.1016/j.mcp.2018.03.001

BACKGROUND: Early diagnosis of leptospirosis is important for ensuring better clinical management and achieving better outcomes. Currently, serological assays suffer from inconsistent performance and are less useful for early diagnosis of leptospirosis. As an alternative, qPCR is more sensitive, specific and able to detect the presence of leptospiral DNA during the acute phase of the infection. Meanwhile, most molecular assays do not detect the non-pathogenic group of Leptospira, even though these groups may also infect humans, although less frequently and less severely.
METHODS: A set of primers and probe targeting rrs genes of 22 Leptospira spp. were designed and evaluated on 31 Leptospira isolates, 41 other organisms and 65 clinical samples from suspected patients.
RESULTS: The developed assay was able to detect as low as 20 fg Leptospira DNA per reaction (equivalent to approximately 4 copies) and showed high specificity against the tested leptospiral strains. No cross amplification was observed with the other organisms. During the evaluation of the confirmed clinical specimens, the developed assay was able to correctly identify all positive samples (n = 10/10). One amplification was observed in a negative sample (n = 1/55). The sequencing of the PCR product of the discordant sample revealed that the sequences were similar to those of L. interrogans and L. kirschneri.
CONCLUSION: The findings suggest that the developed Taqman qPCR assay is sensitive, specific and has potential to be applied in a larger subsequent study.
Fulltext Performance and Characterization of Bi-Metal Compound on Activated Carbon for Hydrogen Sulfide Removal in Biogas

Zulkefli NN, Noor Azam AMI, Masdar MS, Baharuddin NA, Wan Isahak WNR, Mohd Sofian N

Molecules, 2022 Dec 17;27(24).
PMID: 36558155 DOI: 10.3390/molecules27249024

This study reports on the synthesis of bi-metal compound (BMC) adsorbents based on commercial coconut activated carbon (CAC), surface-modified with metal acetate (ZnAc2), metal oxide (ZnO), and the basic compounds potassium hydroxide (KOH) and sodium hydroxide (NaOH). The adsorbents were then characterized by scanning electron microscopy and elemental analysis, microporosity analysis through Brunauer-Emmett-Teller (BET) analysis, and thermal stability via thermogravimetric analysis. Adsorption-desorption test was conducted to determine the adsorption capacity of H2S via 1 L adsorber and 1000 ppm H2S balanced 49.95% for N2 and CO2. Characterization results revealed that the impregnated solution homogeneously covered the adsorbent surface, morphology, and properties. The adsorption test result reveals that the ZnAc2/ZnO/CAC_B had a higher H2S breakthrough adsorption capacity and performed at larger than 90% capability compared with a single modified adsorbent (ZnAc2/CAC). Therefore, the synthesized BMC adsorbents have a high H2S loading, and the abundance and low cost of CAC may lead to favorable adsorbents in H2S captured.
Fulltext Impact Analysis of Potential Induced Degradation on Crystalline Silicon Solar Cell Performance by Correlating Practical Diagnosis with MATLAB Simulation

Hasan AAQ, Alkahtani AA, Islam MA, Alsariera YA, Sathiswary S, Kassim NM, et al.

Materials (Basel), 2022 Nov 15;15(22).
PMID: 36431542 DOI: 10.3390/ma15228056

Extensive research on fault diagnosis is essential to detect various faults that occur to different photovoltaic (PV) panels to keep PV systems operating at peak performance. Here, we present an impact analysis of potential induced degradation (PID) on the current-voltage (I-V) characteristics of crystalline silicon (c-Si) solar cells. The impact of parasitic resistances on solar cell performance is highlighted and linked to fault and degradation. Furthermore, a Simulink model for a single solar cell is proposed and used to estimate the I-V characteristics of a PID-affected PV cell based on experimental results attributes. The measured data show that the fill factor (FF) drops by approximately 13.7% from its initial value due to a decrease in shunt resistance (Rsh). Similarly, the simulation results find that the fill factor degraded by approximately 12% from its initial value. The slight increase in measured data could be due to series resistance effects which were assumed to be zero in the simulated data. This study links simulation and experimental work to confirm the I-V curve behavior of PID-affected PV cells, which could help to improve fault diagnosis methods.
Insights into the decolorization of mono and diazo dyes in single and binary dyes containing wastewater and electricity generation in up-flow constructed wetland coupled microbial fuel cell

Teoh TP, Ong SA, Ho LN, Wong YS, Lutpi NA, Oon YL, et al.

Environ Sci Pollut Res Int, 2023 Feb;30(7):17546-17563.
PMID: 36197611 DOI: 10.1007/s11356-022-23101-w

The treatment of single and binary azo dyes, as well as the effect of the circuit connection, aeration, and plant on the performance of UFCW-MFC, were explored in this study. The decolorization efficiency of Remazol Yellow FG (RY) (single dye: 98.2 %; binary dye: 92.3 %) was higher than Reactive Black 5 (RB5) (single: 92.3 %; binary: 86.7 %), which could be due to monoazo dye (RY) requiring fewer electrons to break the azo bond compared to the diazo dye (RB5). In contrast, the higher decolorization rate of RB5 in binary dye indicated the removal rate was affected by the electron-withdrawing groups in the dye structure. The closed circuit enhanced about 2% of color and 4% of COD removal. Aeration improved the COD removal by 6%, which could be contributed by the mineralization of intermediates. The toxicity of azo dyes was reduced by 11-26% and the degradation pathways were proposed. The dye removal by the plants was increased with a higher contact time. RB5 was more favorable to be uptook by the plant as RB5 holds a higher partial positive charge. 127.39 (RY), 125.82 (RB5), and 58.66 mW/m3 (binary) of maximum power density were generated. The lower power production in treating the binary dye could be due to more electrons being utilized for the degradation of higher dye concentration. Overall, the UFCW-MFC operated in a closed circuit, aerated, and planted conditions achieved the optimum performance in treating binary azo dyes containing wastewater (dye: 87-92%; COD: 91%) compared to the other conditions (dye: 83-92%; COD: 78-87%).
Transformation from biofiltration unit to hybrid constructed wetland-microbial fuel cell: Improvement of wastewater treatment performance and energy recovery

Teoh TP, Koo CJ, Ho LN, Wong YS, Lutpi NA, Tan SM, et al.

Environ Sci Pollut Res Int, 2023 Apr 04.
PMID: 37016256 DOI: 10.1007/s11356-023-26789-6

This study aimed to compare the performance of biofiltration, constructed wetland, and constructed wetland microbial fuel cell (CW-MFC). The transformation from a biofiltration unit to a hybrid CW-MFC was demonstrated with the advantages of improvement of wastewater treatment while generating electricity simultaneously. The introduction of plants to the upper region of the bioreactor enhanced the DO level by 0.8 mg/L, ammonium removal by 5 %, and COD removal by 1 %. The integration of electrodes and external circuits stimulated the degradation rate of organic matter in the anodic region (1 % without aeration and 3 % with aeration) and produced 5.13 mW/m3 of maximum power density. Artificial aeration improved the nitrification efficiency by 38 % and further removed the residual COD to an efficiency of 99 %. The maximum power density was also increased by 3.2 times (16.71 mW/m3) with the aid of aeration. In treating higher organic loading wastewater (3M), the maximum power density showed a significant increment to 78.01 mW/m3 (4.6-fold) and the COD removal efficiency was 98 %. The ohmic overpotential dominated the proportion of total loss (67-91 %), which could be ascribed to the low ionic conductivity. The reduction in activation and concentration loss contributed to the lower internal resistance with the additional aeration and higher organic loading. Overall, the transformation from biofiltration to a hybrid CW-MFC system is worthwhile since the systems quite resemble while CW-MFC could improve the wastewater treatment as well as recover energy from the treated wastewater.
Chemical and biological combined treatment for sugarcane vinasse: selection of parameters and performance studies

Kee WC, Wong YS, Ong SA, Lutpi NA, Sam ST, Dahalan FA, et al.

Environ Sci Pollut Res Int, 2023 May;30(24):65364-65378.
PMID: 37081370 DOI: 10.1007/s11356-023-27046-6

Sugarcane vinasse has been reported as a high strength industrial wastewater that could cause severe environmental pollution due to its complex and bio-refractory compounds. Thus, the combined coagulation and sequencing batch biofilm reactor (SBBR) system was employed for the sugarcane vinasse treatment. This study aims to determine the recommended conditions of various parameters under coagulation and SBBR and investigate the effectiveness of combined processes. First, the approach of the coagulation process could achieve the maximum COD reduction and decolorization efficiencies of 79.0 ± 3.4% and 94.1 ± 1.9%, respectively, under the recommended conditions. Next, SBBR as an integrated biofilm reactor showed excellent synergistic biodegradability, removing 86.6 ± 4.3% COD concentration and 94.6 ± 3.8% color concentration at 3.0 g·COD/L of substrate loading concentration. The kinetic studies of SBBR revealed that the first-order kinetic model was the best fit for COD reduction efficiency. In contrast, the second-order kinetic model was the best fit for decolorization efficiency. The SBBR reaction was further investigated by ultraviolet-visible spectrophotometry (UV-Vis). In the combined processes, SBBR followed by the coagulation process (SBBR-CP) showed greater COD reduction and decolorization efficiencies (97.5 ± 0.3 and 99.4 ± 0.1%) when compared to the coagulation process followed by SBBR (CP-SBBR). This study demonstrated the removal performance and potential application of the combined sequential process to produce effluent that can be reused for bioethanol production and fertigation. This finding provides additional insight for developing effective vinasse treatment using combined chemical and biological processes.
Fulltext Environmentally Benign Water-Soluble Sodium L-2-(1-Imidazolyl) Alkanoic Acids as New Corrosion Inhibitors for Mild Steel in Artificial Seawater

Haque J, Zulkifli MFR, Ismail N, Quraishi MA, Mohd Ghazali MS, Berdimurodov E, et al.

ACS Omega, 2023 Jul 18;8(28):24797-24812.
PMID: 37483193 DOI: 10.1021/acsomega.3c00366

Three novel natural amino acid-derived sodium L-2-(1-imidazolyl) alkanoic acids (IZSs), namely, sodium 2-(1H-imidazol-1-yl)-4-methylpentanoate (IZS-L), sodium 2-(1H-imidazol-1-yl)-3-phenylpropanoate (IZS-P), and sodium 2-(1H-imidazol-1-yl)-4-(methylthio)butanoate (IZS-M), were investigated as corrosion inhibitors. The IZSs were synthesized following the green chemistry principles, and their structure was characterized using FTIR and NMR techniques. The corrosion study results reveal that a moderate concentration of IZSs (having low solution conductivity) showed potential corrosion inhibition for mild steel in artificial seawater. At longer immersion, IZS-P forms a uniform protective film and exhibits the potential inhibition efficiency of 82.46% at 8.4 mmol L-1. Tafel polarization results reveal that IZS-P and IZS-M act as mixed types with an anodic predominantly corrosion inhibitor. The electrochemical impedance spectroscopy results signify that IZSs inhibit mild steel corrosion through the formation of an inhibitor film on the metal surface, which was further confirmed by the FTIR, SEM, EDX, and XPS studies. DFT result shows that in IZS-P, the benzylic group (-CH2-Ph) has greater electron distribution compared to isobutyl (-CH2CH(CH3)2) in IZS-L and methythioethyl group (-CH2CH2SCH3) which supported the corrosion inhibition performance at longer immersion [IZS-P (82.46%) > IZS-M (67.19%) > IZS-L (24.77%)].
Exploring the potential of thermophilic anaerobic co-digestion between agro-industrial waste and water hyacinth: operational performance, kinetic study and degradation pathway

Chai A, Wong YS, Ong SA, Lutpi NA, Sam ST, Wirach T, et al.

Bioprocess Biosyst Eng, 2023 Jul;46(7):995-1009.
PMID: 37160769 DOI: 10.1007/s00449-023-02879-0

Anaerobic co-digestion (co-AD) of agro-industrial waste, namely, palm oil mill effluent (POME) and sugarcane vinasse (Vn), with water hyacinth (WH) as co-substrate was carried out in two separate Anaerobic Suspended Growth Closed Bioreactors (ASGCBs) under thermophilic (55 °C) conditions. The highest chemical oxygen demand (COD) and soluble COD reduction in co-AD of POME-WH (78.61%, 78.86%) is slightly higher than co-AD of Vn-WH (75.75%, 78.24%). However, VFA reduction in co-AD of POME-WH (96.41%) is higher compared to co-AD of Vn-WH (85.94%). Subsequently, biogas production peaked at 13438 mL/day values and 16122 mL/day for co-AD of POME-WH and Vn-WH, respectively. However, the methane content was higher in the co-AD of POME-WH (72.04%) than in the co-AD of Vn-WH (69.86%). Growth yield (YG), maximum specific substrate utilization rate (rx,max) and maximum specific biomass growth rate (μmax) are higher in co-AD of POME-WH, as supported by the higher mixed liquor volatile suspended solids (MLVSS) and COD reduction efficiency compared to co-AD of Vn-WH. However, methane yield ([Formula: see text]) reported in the co-AD of POME-WH and Vn-WH are 0.2748 and 0.3112 L CH4/g CODreduction, respectively, which suggests that WH is a more suitable co-substrate for Vn compared to POME.
Fulltext Factors Associated With Length of Stay for Patients With Stroke in Malaysia

Ismail A, Reffien MAM, Ibrahim NM, Sobri HNM, Abidin NDIZ, Rusli SASS, et al.

Glob J Qual Saf Healthc, 2020 Nov;3(4):134-138.
PMID: 37260578 DOI: 10.36401/JQSH-20-10

INTRODUCTION: Globally, stroke continues to become a significant public health issue contributing to one of the significant causes of morbidity and mortality. The study aimed to describe the characteristics of patients with stroke who were admitted to a teaching hospital in Malaysia and to determine the factors associated with length of stay (LOS).
METHODS: This is a single-center, cross-sectional study using in-patient data maintained by the Case-Mix Unit of a teaching hospital in Malaysia from 2016 to 2017. The study included all patients with International Classification of Disease (ICD) code 164 (stroke, not specified as hemorrhage or infarct). The significance of association was determined using nonparametric tests in the form of the Mann-Whitney U test and the Kruskal-Wallis test.
RESULTS: A total of 162 stroke patients from 2016 to 2017 from Case-Mix database were included in the study. The age ranged from 31 to 97 years old. The minimum and maximum LOS for patients with stroke ranged from 1 to 17 days. The severity of illness was found to be significantly associated with longer LOS (p < 0.001); however, age, sex, and presence of co-morbidities did not show any significant association.
CONCLUSION: Despite its limitations, this study is an essential first step to examine the characteristics of patients with stroke and to determine the factors associated with LOS.
Fulltext Air-Processable Perovskite Solar Cells by Hexamine Molecule Phase Stabilization

Alias N, Ali Umar A, Sadikin SN, Ridwan J, Hamzah AA, Ali Umar MI, et al.

ACS Omega, 2023 May 30;8(21):18874-18881.
PMID: 37273642 DOI: 10.1021/acsomega.3c01236

Perovskite solar cells have emerged as a potential energy alternative due to their low cost of fabrication and high power conversion efficiency. Unfortunately, their poor ambient stability has critically limited their industrialization and application in real environmental conditions. Here, we show that by introducing hexamine molecules into the perovskite lattice, we can enhance the photoactive phase stability, enabling high-performance and air-processable perovskite solar cells. The unencapsulated and freshly prepared perovskite solar cells produce a power conversion efficiency of 16.83% under a 100 mW cm-2 1.5G solar light simulator and demonstrate high stability properties when being stored for more than 1500 h in humid air with relative humidity ranging from 65 to 90%. We envisage that our findings may revolutionize perovskite solar cell research, pushing the performance and stability to the limit and bringing the perovskite solar cells toward industrialization.
Sex estimation of Malaysian sub-adults using craniometrics: A computed tomography study

Syed Mohd Hamdan SN, Rahmat RA, Abdul Razak F, Abd Kadir KA, Mohd Faizal Abdullah ER, Ibrahim N

Leg Med (Tokyo), 2023 Sep;64:102275.
PMID: 37229938 DOI: 10.1016/j.legalmed.2023.102275

Sex estimation is crucial in biological profiling of skeletal human remains. Methods used for sex estimation in adults are less effective for sub-adults due to varied cranium patterns during the growth period. Hence, this study aimed to develop a sex estimation model for Malaysian sub-adults using craniometric measurements obtained through multi-slice computed tomography (MSCT). A total of 521 cranial MSCT dataset of sub-adult Malaysians (279 males, 242 females; 0-20 years old) were collected. Mimics software version 21.0 (Materialise, Leuven, Belgium) was used to construct three-dimensional (3D) models. A plane-to-plane (PTP) protocol was utilised to measure 14 selected craniometric parameters. Discriminant function analysis (DFA) and binary logistic regression (BLR) were used to statistically analyze the data. In this study, low level of sexual dimorphism was observed in cranium below 6 years old. The level was then increased with age. For sample validation data, the accuracy of DFA and BLR in estimating sex improved with age from 61.6% to 90.3%. All age groups except 0-2 and 3-6 showed high accuracy percentage (≥75%) when tested using DFA and BLR. DFA and BLR can be utilised to estimate sex for Malaysian sub-adult using MSCT craniometric measurements. However, BLR showed higher accuracy than DFA in sex estimation of sub-adults.
Fulltext Mathematical Modelling of Canola Oil Biodegradation and Optimisation of Biosurfactant Production by an Antarctic Bacterial Consortium Using Response Surface Methodology

Zahri KNM, Khalil KA, Gomez-Fuentes C, Zulkharnain A, Sabri S, Convey P, et al.

Foods, 2021 Nov 14;10(11).
PMID: 34829082 DOI: 10.3390/foods10112801

An Antarctic soil bacterial consortium (reference BS14) was confirmed to biodegrade canola oil, and kinetic studies on this biodegradation were carried out. The purpose of this study was to examine the ability of BS14 to produce biosurfactants during the biodegradation of canola oil. Secondary mathematical equations were chosen for kinetic analyses (Monod, Haldane, Teissier-Edwards, Aiba and Yano models). At the same time, biosurfactant production was confirmed through a preliminary screening test and further optimised using response surface methodology (RSM). Mathematical modelling demonstrated that the best-fitting model was the Haldane model for both waste (WCO) and pure canola oil (PCO) degradation. Kinetic parameters including the maximum degradation rate (μmax) and maximum concentration of substrate tolerated (Sm) were obtained. For WCO degradation these were 0.365 min-1 and 0.308%, respectively, while for PCO they were 0.307 min-1 and 0.591%, respectively. The results of all preliminary screenings for biosurfactants were positive. BS14 was able to produce biosurfactant concentrations of up to 13.44 and 14.06 mg/mL in the presence of WCO and PCO, respectively, after optimisation. The optimum values for each factor were determined using a three-dimensional contour plot generated in a central composite design, where a combination of 0.06% salinity, pH 7.30 and 1.55% initial substrate concentration led to the highest biosurfactant production when using WCO. Using PCO, the highest biosurfactant yield was obtained at 0.13% salinity, pH 7.30 and 1.25% initial substrate concentration. This study could help inform the development of large-scale bioremediation applications, not only for the degradation of canola oil but also of other hydrocarbons in the Antarctic by utilising the biosurfactants produced by BS14.
Fulltext A failure in decryption process for bivariate polynomial reconstruction problem cryptosystem

Yusof SN, Kamel Ariffin MR, Yip SC, Lau TSC, Mahad Z, Chin JJ, et al.

Heliyon, 2024 Feb 29;10(4):e25470.
PMID: 38370193 DOI: 10.1016/j.heliyon.2024.e25470

In 1999, the Polynomial Reconstruction Problem (PRP) was put forward as a new hard mathematics problem. A univariate PRP scheme by Augot and Finiasz was introduced at Eurocrypt in 2003, and this cryptosystem was fully cryptanalyzed in 2004. In 2013, a bivariate PRP cryptosystem was developed, which is a modified version of Augot and Finiasz's original work. This study describes a decryption failure that can occur in both cryptosystems. We demonstrate that when the error has a weight greater than the number of monomials in a secret polynomial, p, decryption failure can occur. The result of this study also determines the upper bound that should be applied to avoid decryption failure.
Fulltext Knowledge, attitude and practice about leptospirosis prevention among town service workers in northeastern Malaysia: a cross sectional study

Azfar ZM, Nazri SM, Rusli AM, Maizurah O, Zahiruddin WM, Azwany YN, et al.

J Prev Med Hyg, 2018 Mar;59(1):E92-E98.
PMID: 29938244 DOI: 10.15167/2421-4248/jpmh2018.59.1.776

INTRODUCTION: Many efforts have been done to reduce leptospirosis infections in Malaysia especially among high risk groups including town service workers. Town service workers are more likely to be exposed to the leptospiral infection resulting from their occupational activities.
METHODS: A cross sectional study was conducted in northeastern Malaysia involving 321 town service workers who were subjected to answer an interviewer-guided validated questionnaire which consists of sociodemographic, knowledge, attitude and practice information. Data were entered and analyzed using SPSS Version 20.
RESULTS: All of the respondents were Malay with mean (SD) age of 40.6 (10.28) years old. The mean (SD) duration of employment was 12.1 (9.62) years. Fifty four respondents (16.8%) had never heard of leptospirosis. Among the respondents, 215 (67.0%) of them had poor knowledge on leptospirosis. Meanwhile, 167 (52.0%) and only 128 (39.9%) of them had satisfactory attitude and practice respectively. It was found that knowledge on risk factors for leptospirosis was lacking. There were high risk attitudes such as drinking habit and protective equipment used during working with the favourable answers ranged from 67.3% to 89.1%. The weakest area identified in their practice was also on the use of protective equipment.
CONCLUSIONS: The workers' level of knowledge and practice were relatively poor despite an overall good practice on leptospirosis. This finding might expose them to an increased risk of contracting leptospirosis. Identified weak areas in their knowledge, attitude and practice will assist the policy makers to develop a focused and well-directed intervention program on leptospirosis infection.
Marrow Fat-Cortical Bone Relationship in β-Thalassemia: A Study Using MRI

Ismail UN, Azlan CA, Khairullah S, Azman RR, Omar NF, Md Shah MN, et al.

J Magn Reson Imaging, 2024 Mar 31.
PMID: 38556790 DOI: 10.1002/jmri.29366

BACKGROUND: Growing evidence suggests that marrow adipocytes play an active role in the regulation of bone metabolism and hematopoiesis. However, research on the relationship between bone and fat in the context of hematological diseases, particularly β-thalassemia, remains limited.
PURPOSE: To investigate the relationship between marrow fat and cortical bone thickness in β-thalassemia and to identify key determinants influencing these variables.
STUDY TYPE: Prospective.
SUBJECTS: Thirty-five subjects in four subject groups of increasing disease severity: 6 healthy control (25.0 ± 5.3 years, 2 male), 4 β-thalassemia minor, 13 intermedia, and 12 major (29.1 ± 6.4 years, 15 male).
FIELD STRENGTH/SEQUENCE: 3.0 T, 3D fast low angle shot sequence and T1-weighted turbo spin echo.
ASSESSMENT: Analyses on proton density fat fraction (PDFF) and R2* values in femur subregions (femoral head, greater trochanter, intertrochanteric, diaphysis, distal) and cortical thickness (CBI) of the subjects' left femur. Clinical data such as age, sex, body mass index (BMI), and disease severity were also included.
STATISTICAL TESTS: One-way analysis of variance (ANOVA), mixed ANOVA, Pearson correlation and multiple regression. P-values <0.05 were considered significant.
RESULTS: Bone marrow PDFF significantly varied between the femur subregions, F(2.89,89.63) = 44.185 and disease severity, F(1,3) = 12.357. A significant interaction between subject groups and femur subregions on bone marrow PDFF was observed, F(8.67,89.63) = 3.723. Notably, a moderate positive correlation was observed between PDFF and CBI (r = 0.33-0.45). Multiple regression models for both PDFF (R2 = 0.476, F(13,151) = 10.547) and CBI (R2 = 0.477, F(13,151) = 10.580) were significant. Significant predictors for PDFF were disease severity (βTMi = 0.36, βTMa = 0.17), CBI (β = 0.24), R2* (β = -0.32), and height (β = -0.29) while for CBI, the significant determinants were sex (β = -0.27), BMI (β = 0.55), disease severity (βTMi = 2.15), and PDFF (β = 0.25).
DATA CONCLUSION: This study revealed a positive correlation between bone marrow fat fraction and cortical bone thickness in β-thalassemia with varying disease severity, potentially indicating a complex interplay between bone health and marrow composition.
EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.
Enhancement of energy recovery from caffeine wastewater in constructed wetland-microbial fuel cell through operating conditions

Teoh TP, Ong SA, Ho LN, Wong YS, Lutpi NA, Tan SM, et al.

Environ Sci Pollut Res Int, 2023 Jul;30(35):84397-84411.
PMID: 37358771 DOI: 10.1007/s11356-023-28362-7

The enhancement of up-flow constructed wetland-microbial fuel cell (UFCW-MFC) performance in energy retrieval from caffeine containing wastewater has been explored via various operating conditions (hydraulic retention time (HRT), multianode (MA), multicathode current collector (MC), external resistance). The anaerobic decaffeination and COD removal improved by 37 and 12% as the HRT extended from 1 to 5 d. The increment in contact time between the microbes and organic substrates promoted the degradation and contributed to higher power output (3.4-fold), CE (eightfold), and NER (14-16-fold). The MA and MC connections facilitated the electron transfer rate and the degradation rate of organic substrates in the multiple anodic zones, which enhanced the removal efficiency in the anaerobic compartment (Caffeine: 4.2%; COD: 7.4%) and led to higher electricity generation (Power: 4.7-fold) and energy recovery (CE: 1.4-fold; NER: 2.3-2.5-fold) compared to SA. The lower external resistance favored the growth of electrogens and induced higher electron flux, where the best treatment performance and electricity production was obtained when the external resistance approached the internal resistance. Overall, it was noteworthy that the optimum operating conditions were achieved with 5 d HRT, MA, and MC connection along with external resistance of 200 Ω, which significantly outperformed the initial conditions (1 d HRT, SA connection, and 1000 Ω) by 43.7 and 29.8% of caffeine and COD removal in the anaerobic compartment, respectively as well as 14-fold of power generation.

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