Displaying publications 401 - 420 of 529 in total

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  1. Fulltext An Insight into Amorphous Shear Band in Magnetorheological Solid by Atomic Force Microscope
    Johari MAF, Sarman AM, Mazlan SA, U U, Nordin NA, Abdul Aziz SA, et al.
    Materials (Basel), 2021 Aug 05;14(16).
    PMID: 34442907 DOI: 10.3390/ma14164384
    Micro mechanism consideration is critical for gaining a thorough understanding of amorphous shear band behavior in magnetorheological (MR) solids, particularly those with viscoelastic matrices. Heretofore, the characteristics of shear bands in terms of formation, physical evolution, and response to stress distribution at the localized region have gone largely unnoticed and unexplored. Notwithstanding these limitations, atomic force microscopy (AFM) has been used to explore the nature of shear band deformation in MR materials during stress relaxation. Stress relaxation at a constant low strain of 0.01% and an oscillatory shear of defined test duration played a major role in the creation of the shear band. In this analysis, the localized area of the study defined shear bands as varying in size and dominantly deformed in the matrix with no evidence of inhibition by embedded carbonyl iron particles (CIPs). The association between the shear band and the adjacent zone was further studied using in-phase imaging of AFM tapping mode and demonstrated the presence of localized affected zone around the shear band. Taken together, the results provide important insights into the proposed shear band deformation zone (SBDZ). This study sheds a contemporary light on the contentious issue of amorphous shear band deformation behavior and makes several contributions to the current literature.
  2. Fulltext Chitosan/Poly Vinyl Alcohol/Graphene Oxide Based pH-Responsive Composite Hydrogel Films: Drug Release, Anti-Microbial and Cell Viability Studies
    Khan MUA, Yaqoob Z, Ansari MNM, Razak SIA, Raza MA, Sajjad A, et al.
    Polymers (Basel), 2021 Sep 16;13(18).
    PMID: 34578025 DOI: 10.3390/polym13183124
    The composite hydrogels were produced using the solution casting method due to the non-toxic and biocompatible nature of chitosan (CS)/polyvinyl alcohol (PVA). The best composition was chosen and crosslinked with tetraethyl orthosilicate (TEOS), after which different amounts of graphene oxide (GO) were added to develop composite hydrogels. Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle was used to analyze the hydrogels. The samples were also evaluated for swelling abilities in various mediums. The drug release profile was studied in phosphate-buffered saline (PBS) at a pH of 7.4. To predict the mechanism of drug release, the data were fitted into kinetic models. Finally, antibacterial activity and cell viability data were obtained. FTIR studies revealed the successful synthesis of CS/PVA hydrogels and GO/CS/PVA in hydrogel composite. SEM showed no phase separation of the polymers, whereas AFM showed a decrease in surface roughness with an increase in GO content. 100 µL of crosslinker was the critical concentration at which the sample displayed excellent swelling and preserved its structure. Both the crosslinked and composite hydrogel showed good swelling. The most acceptable mechanism of drug release is diffusion-controlled, and it obeys Fick's law of diffusion for drug released. The best fitting of the zero-order, Hixson-Crowell and Higuchi models supported our assumption. The GO/CS/PVA hydrogel composite showed better antibacterial and cell viability behaviors. They can be better biomaterials in biomedical applications.
  3. Fulltext A Review on Rhenium Disulfide: Synthesis Approaches, Optical Properties, and Applications in Pulsed Lasers
    Fadhel MM, Ali N, Rashid H, Sapiee NM, Hamzah AE, Zan MSD, et al.
    Nanomaterials (Basel), 2021 Sep 12;11(9).
    PMID: 34578683 DOI: 10.3390/nano11092367
    Rhenium Disulfide (ReS2) has evolved as a novel 2D transition-metal dichalcogenide (TMD) material which has promising applications in optoelectronics and photonics because of its distinctive anisotropic optical properties. Saturable absorption property of ReS2 has been utilized to fabricate saturable absorber (SA) devices to generate short pulses in lasers systems. The results were outstanding, including high-repetition-rate pulses, large modulation depth, multi-wavelength pulses, broadband operation and low saturation intensity. In this review, we emphasize on formulating SAs based on ReS2 to produce pulsed lasers in the visible, near-infrared and mid-infrared wavelength regions with pulse durations down to femtosecond using mode-locking or Q-switching technique. We outline ReS2 synthesis techniques and integration platforms concerning solid-state and fiber-type lasers. We discuss the laser performance based on SAs attributes. Lastly, we draw conclusions and discuss challenges and future directions that will help to advance the domain of ultrafast photonic technology.
  4. Fulltext Prevalence of burnout among Universiti Sains Malaysia medical students
    Chin ARW, Chua YY, Chu MN, Mahadi NF, Yusof MSB, Wong MS, et al.
    Education in Medicine Journal, 2016;8(3):61-74.
    MyJurnal
    Introduction: The academic life of medical students can be considered as psychological toxic. About half of United States medical students experience burnout and more than 25% experience depression. This study aimed to determine the prevalence of burnout among medical students in a Malaysian medical school and its associated factors.
    Methods: This is a cross sectional study of 452 medical students from Universiti Sains Malaysia (USM). Copenhagen Burnout Inventory was distributed via Google Forms through Facebook Messenger. Ethical approval was obtained from the Human Research Ethics Committee USM. Data were collected via Google Sheets. Each respondent only submitted one Google Form as no resubmission link was provided once completed Google Form was submitted.
    Result: The prevalence of burnout among USM medical students was 67.9%. Personal burnout was the highest (81.6%), followed by work-related burnout (73.7%) and client-related burnout (68.6%). The analysis showed that regardless of year of study, gender and ethnicity (all P > 0.05), USM medical students were vulnerable to burnout.
    Conclusion: The prevalence of burnout among USM medical students was high and the most prevalent type of burnout was personal burnout. Therefore, burnout among medical students should be a concern and must be addressed to prevent subsequent unwanted consequences.
  5. Influence of citric acid on the physical and biomineralization ability of freeze/thaw poly(vinyl alcohol) hydrogel
    Wahid MNA, Abd Razak SI, Abdul Kadir MR, Hassan R, Nayan NHM, Mat Amin KA
    J Biomater Appl, 2018 07;33(1):94-102.
    PMID: 29716417 DOI: 10.1177/0885328218771195
    This work reports the modification of freeze/thaw poly(vinyl alcohol) hydrogel using citric acid as the bioactive molecule for hydroxyapatite formation in simulated body fluid. Inclusion of 1.3 mM citric acid into the poly(vinyl alcohol) hydrogel showed that the mechanical strength, crystalline phase, functional groups and swelling ability were still intact. Adding citric acid at higher concentrations (1.8 and 2.3 mM), however, resulted in physically poor hydrogels. Presence of 1.3 mM of citric acid showed the growth of porous hydroxyapatite crystals on the poly(vinyl alcohol) surface just after one day of immersion in simulated body fluid. Meanwhile, a fully covered apatite layer on the poly(vinyl alcohol) surface plus the evidence of apatite forming within the hydrogel were observed after soaking for seven days. Gel strength of the soaked poly(vinyl alcohol)/citric acid-1.3 mM hydrogel revealed that the load resistance was enhanced compared to that of the neat poly(vinyl alcohol) hydrogel. This facile method of inducing rapid growth of hydroxyapatite on the hydrogel surface as well as within the hydrogel network can be useful for guided bone regenerative materials.
  6. Induction of apoptosis and G2/M arrest by ampelopsin E from Dryobalanops towards triple negative breast cancer cells, MDA-MB-231
    Rahman NA, Yazan LS, Wibowo A, Ahmat N, Foo JB, Tor YS, et al.
    BMC Complement Altern Med, 2016;16:354.
    PMID: 27609190 DOI: 10.1186/s12906-016-1328-1
    Several compounds isolated from Dryobalanops have been reported to exhibit cytotoxic effects to several cancer cell lines. This study investigated the cytotoxic effects, cell cycle arrest and mode of cell death in ampelopsin E-treated triple negative cells, MDA-MB-231.
  7. Fulltext Material Characterization of a Magnetorheological Fluid Subjected to Long-Term Operation in Damper
    Utami D, Ubaidillah, Mazlan SA, Imaduddin F, Nordin NA, Bahiuddin I, et al.
    Materials (Basel), 2018 Nov 06;11(11).
    PMID: 30404193 DOI: 10.3390/ma11112195
    This paper investigates the field-dependent rheological properties of magnetorheological (MR) fluid used to fill in MR dampers after long-term cyclic operation. For testing purposes, a meandering MR valve was customized to create a double-ended MR damper in which MR fluid flowed inside the valve due to the magnetic flux density. The test was conducted for 170,000 cycles using a fatigue dynamic testing machine which has 20 mm of stroke length and 0.4 Hz of frequency. Firstly, the damping force was investigated as the number of operating cycles increased. Secondly, the change in viscosity of the MR fluid was identified as in-use thickening (IUT). Finally, the morphological observation of MR particles was undertaken before and after the long-term operation. From these tests, it was demonstrated that the damping force increased as the number of operating cycles increases, both when the damper is turn on (on-state) and off (off-state). It is also observed that the particle size and shape changed due to the long operation, showing irregular particles.
  8. Fulltext Enhancement of Viscoelastic and Electrical Properties of Magnetorheological Elastomers with Nanosized Ni-Mg Cobalt-Ferrites as Fillers
    Abdul Aziz SA, Mazlan SA, Ubaidillah U, Shabdin MK, Yunus NA, Nordin NA, et al.
    Materials (Basel), 2019 Oct 28;12(21).
    PMID: 31661837 DOI: 10.3390/ma12213531
    Carbon-based particles, such as graphite and graphene, have been widely used as a filler in magnetorheological elastomer (MRE) fabrication in order to obtain electrical properties of the material. However, these kinds of fillers normally require a very high concentration of particles to enhance the conductivity property. Therefore, in this study, the nanosized Ni-Mg cobalt ferrite is introduced as a filler to soften MRE and, at the same time, improve magnetic, rheological, and conductivity properties. Three types of MRE samples without and with different compositions of Mg, namely Co0.5Ni0.2Mg0.3Fe2O4 (A1) and Co0.5Ni0.1Mg0.4Fe2O4 (A2), are fabricated. The characterization related to the micrograph, magnetic, and rheological properties of the MRE samples are analyzed using scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), and the rheometer. Meanwhile, the effect of the nanosized Ni-Mg cobalt ferrites on the electrical resistance property is investigated and compared with the different Mg compositions. It is shown that the storage modulus of the MRE sample with the nanosized Ni-Mg cobalt ferrites is 43% higher than that of the MRE sample without the nanomaterials. In addition, it is demonstrated that MREs with the nanosized Ni-Mg cobalt ferrites exhibit relatively low electrical resistance at the on-state as compared to the off-state condition, because MRE with a higher Mg composition shows lower electrical resistance when higher current flow occurs through the materials. This salient property of the proposed MRE can be effectively and potentially used as an actuator to control the viscoelastic property of the magnetic field or sensors to measure the strain of the flexible structures by the electrical resistance signal.
  9. Isolation and identification of salt-tolerant plant-growth-promoting rhizobacteria and their application for rice cultivation under salt stress
    Sultana S, Paul SC, Parveen S, Alam S, Rahman N, Jannat B, et al.
    Can J Microbiol, 2020 Feb;66(2):144-160.
    PMID: 31714812 DOI: 10.1139/cjm-2019-0323
    Growth and productivity of rice are negatively affected by soil salinity. However, some salt-tolerant rhizosphere-inhabiting bacteria can improve salt resistance of plants, thereby augmenting plant growth and production. Here, we isolated a total of 53 plant-growth-promoting rhizobacteria (PGPR) from saline and non-saline areas in Bangladesh where electrical conductivity was measured as >7.45 and <1.80 dS/m, respectively. Bacteria isolated from saline areas were able to grow in a salt concentration of up to 2.60 mol/L, contrary to the isolates collected from non-saline areas that did not survive beyond 854 mmol/L. Among the salt-tolerant isolates, Bacillus aryabhattai, Achromobacter denitrificans, and Ochrobactrum intermedium, identified by comparing respective sequences of 16S rRNA using the NCBI GenBank, exhibited a higher amount of atmospheric nitrogen fixation, phosphate solubilization, and indoleacetic acid production at 200 mmol/L salt stress. Salt-tolerant isolates exhibited greater resistance to heavy metals and antibiotics, which could be due to the production of an exopolysaccharide layer outside the cell surface. Oryza sativa L. fertilized with B. aryabhattai MS3 and grown under 200 mmol/L salt stress was found to be favoured by enhanced expression of a set of at least four salt-responsive plant genes: BZ8, SOS1, GIG, and NHX1. Fertilization of rice with osmoprotectant-producing PGPR, therefore, could be a climate-change-preparedness strategy for coastal agriculture.
  10. Correlation and assessment of coronary artery luminal stenosis: Post-mortem computed tomography angiogram versus histopathology
    Chainchel Singh MK, Abdul Rashid SN, Abdul Hamid S, Mahmood MS, Feng SS, Mohd Nawawi H, et al.
    Forensic Sci Int, 2020 Mar;308:110171.
    PMID: 32032870 DOI: 10.1016/j.forsciint.2020.110171
    BACKGROUND: Post-mortem Computed Tomography (PMCT) allows non-invasive or minimally invasive detection of findings that may or may not be visible during conventional autopsy, however, it does not allow the investigator to draw any conclusions regarding patency of the vessel's lumen. To address this deficiency, Post-mortem Computed Tomography Angiography (PMCTA) utilizing different contrast media and techniques have been introduced with various studies looking at the correlation between PMCTA, autopsy (gross) findings and coronary artery histology in diagnosing coronary artery disease.

    OBJECTIVES: The aim of this study is to investigate the sensitivity and specificity of PMCTA in diagnosing coronary artery stenosis using water-based contrast media introduced though the vessels of the neck, compared to the gold standard of diagnosis i.e. gross and histological evaluation of the coronary artery.

    METHOD: This was a cross sectional study of 158 arterial sections involving 37 subjects recruited from the National Institute of Forensic Medicine (IPFN), Hospital Kuala Lumpur (HKL). An unenhanced PMCT was performed followed by PMCTA using water-based contrast media introduced though the vessels of the neck. Coronary artery stenosis was determined using multiplanar reconstructionD while the degree of stenosis was determined by calculating the percentage of luminal diameter divided by the diameter of the vessel internal elastic.

    RESULTS: The analysis of PMCTA and histopathology examinations revealed a sensitivity of 61.5%, specificity of 91.7%; positive predictive value (PPV) of 40.0% and negative predictive value (NPV) of 96.4%.

    CONCLUSION: PMCTA utilizing water-based contrast introduced though the vessels of the neck yielded similar results as other methods and techniques of PMCTA. We would therefore conclude that PMCTA utilizing this technique could be used to assess the degree of calcification and the presence of significant stenosis.

  11. Non-parametric multiple inputs prediction model for magnetic field dependent complex modulus of magnetorheological elastomer
    Saharuddin KD, Ariff MHM, Bahiuddin I, Ubaidillah U, Mazlan SA, Aziz SAA, et al.
    Sci Rep, 2022 Feb 17;12(1):2657.
    PMID: 35177686 DOI: 10.1038/s41598-022-06643-4
    This study introduces a novel platform to predict complex modulus variables as a function of the applied magnetic field and other imperative variables using machine learning. The complex modulus prediction of magnetorheological (MR) elastomers is a challenging process, attributable to the material's highly nonlinear nature. This problem becomes apparent when considering various possible fabrication parameters. Furthermore, traditional parametric modeling methods are limited when applied to solve larger-scale cases involving large databases. Consequently, the application of non-parametric modeling such as machine learning has gained increasing attraction in recent years. Therefore, this work proposes a data-driven approach for predicting multiple input-dependent complex moduli using feedforward neural networks. Besides excitation frequency and magnetic flux density as operating conditions, the inputs consider compositions and curing conditions represented by magnetic particle weight percentage and the curing magnetic field, respectively. Extreme learning machines and artificial neural networks were used to train the models. The simulation results obtained at various curing conditions and other inputs confirm that the predicted complex modulus has high accuracy with an R2 of about 0.997, as compared to the experimental results. Furthermore, the predicted complex modulus pattern and magnetorheological effect agree with the experimental data using both the learned and unlearned data.
  12. Fulltext A scoping review of clinical reasoning research with Asian healthcare professionals
    Lee CY, Jenq CC, Chandratilake M, Chen J, Chen MM, Nishigori H, et al.
    Adv Health Sci Educ Theory Pract, 2021 Dec;26(5):1555-1579.
    PMID: 34254202 DOI: 10.1007/s10459-021-10060-z
    Clinical reasoning is the thought process that guides practice. Although a plethora of clinical reasoning studies in healthcare professionals exists, the majority appear to originate from Western cultures. A scoping review was undertaken to examine clinical reasoning related research across Asian cultures. PubMed, SciVerse Scopus, Web of Science and Airiti Library databases were searched. Inclusion criteria included full-text articles published in Asian countries (2007 to 2019). Search terms included clinical reasoning, thinking process, differential diagnosis, decision making, problem-based learning, critical thinking, healthcare profession, institution, medical students and nursing students. After applying exclusion criteria, n = 240 were included in the review. The number of publications increased in 2012 (from 5%, n = 13 in 2011 to 9%, n = 22) with a steady increase onwards to 12% (n = 29) in 2016. South Korea published the most articles (19%, n = 46) followed by Iran (17%, n = 41). Nurse Education Today published 11% of the articles (n = 26), followed by BMC Medical Education (5%, n = 13). Nursing and Medical students account for the largest population groups studied. Analysis of the articles resulted in seven themes: Evaluation of existing courses (30%, n = 73) being the most frequently identified theme. Only seven comparative articles showed cultural implications, but none provided direct evidence of the impact of culture on clinical reasoning. We illuminate the potential necessity of further research in clinical reasoning, specifically with a focus on how clinical reasoning is affected by national culture. A better understanding of current clinical reasoning research in Asian cultures may assist curricula developers in establishing a culturally appropriate learning environment.
  13. Smart and pH-sensitive rGO/Arabinoxylan/chitosan composite for wound dressing: In-vitro drug delivery, antibacterial activity, and biological activities
    Khan MUA, Haider S, Raza MA, Shah SA, Razak SIA, Kadir MRA, et al.
    Int J Biol Macromol, 2021 Dec 01;192:820-831.
    PMID: 34648803 DOI: 10.1016/j.ijbiomac.2021.10.033
    Carbohydrate polymers are biological macromolecules that have sparked a lot of interest in wound healing due to their outstanding antibacterial properties and sustained drug release. Arabinoxylan (ARX), Chitosan (CS), and reduced graphene oxide (rGO) sheets were combined and crosslinked using tetraethyl orthosilicate (TEOS) as a crosslinker to fabricate composite hydrogels and assess their potential in wound dressing for skin wound healing. Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM), and biological assays were used to evaluate the composite hydrogels. FTIR validated the effective fabrication of the composite hydrogels. The rough morphologies of the composite hydrogels were revealed by SEM and AFM (as evident from the Ra values). ATC-4 was discovered to have the roughest surface. TEM revealed strong homogeneous anchoring of the rGO to the polymer matrix. However, with higher amount of rGO agglomeration was detected. The % swelling at various pHs (1-13) revealed that the hydrogels were pH-sensitive. The controlled release profile for the antibacterial drug (Silver sulfadiazine) evaluated at various pH values (4.5, 6.8, and 7.4) in PBS solution and 37 °C using the Franz diffusion method revealed maximal drug release at pH 7.4 and 37 °C. The antibacterial efficacy of the composite hydrogels against pathogens that cause serious skin diseases varied. The MC3T3-E1 cell adhered, proliferated, and differentiated well on the composite hydrogels. MC3T3-E1 cell also illustrated excellent viability (91%) and proper cylindrical morphologies on the composite hydrogels. Hence, the composite hydrogels based on ARX, CS, and rGO are promising biomaterials for treating and caring for skin wounds.
  14. Fulltext Development of Antibacterial, Degradable and pH-Responsive Chitosan/Guar Gum/Polyvinyl Alcohol Blended Hydrogels for Wound Dressing
    Khan MUA, Iqbal I, Ansari MNM, Razak SIA, Raza MA, Sajjad A, et al.
    Molecules, 2021 Sep 30;26(19).
    PMID: 34641480 DOI: 10.3390/molecules26195937
    The present research is based on the fabrication preparation of CS/PVA/GG blended hydrogel with nontoxic tetra orthosilicate (TEOS) for sustained paracetamol release. Different TEOS percentages were used because of their nontoxic behavior to study newly designed hydrogels' crosslinking and physicochemical properties. These hydrogels were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and wetting to determine the functional, surface morphology, hydrophilic, or hydrophobic properties. The swelling analysis in different media, degradation in PBS, and drug release kinetics were conducted to observe their response against corresponding media. The FTIR analysis confirmed the components added and crosslinking between them, and surface morphology confirmed different surface and wetting behavior due to different crosslinking. In various solvents, including water, buffer, and electrolyte solutions, the swelling behaviour of hydrogel was investigated and observed that TEOS amount caused less hydrogel swelling. In acidic pH, hydrogels swell the most, while they swell the least at pH 7 or higher. These hydrogels are pH-sensitive and appropriate for controlled drug release. These hydrogels demonstrated that, as the ionic concentration was increased, swelling decreased due to decreased osmotic pressure in various electrolyte solutions. The antimicrobial analysis revealed that these hydrogels are highly antibacterial against Gram-positive (Staphylococcus aureus and Bacillus cereus) and Gram negative (Pseudomonas aeruginosa and Escherichia coli) bacterial strains. The drug release mechanism was 98% in phosphate buffer saline (PBS) media at pH 7.4 in 140 min. To analyze drug release behaviour, the drug release kinetics was assessed against different mathematical models (such as zero and first order, Higuchi, Baker-Lonsdale, Hixson, and Peppas). It was found that hydrogel (CPG2) follows the Peppas model with the highest value of regression (R2 = 0.98509). Hence, from the results, these hydrogels could be a potential biomaterial for wound dressing in biomedical applications.
  15. Fulltext Dual Properties of Polyvinyl Alcohol-Based Magnetorheological Plastomer with Different Ratio of DMSO/Water
    Hapipi NM, Mazlan SA, Ubaidillah U, Abdul Aziz SA, Choi SB, Nordin NA, et al.
    Sensors (Basel), 2021 Nov 22;21(22).
    PMID: 34833835 DOI: 10.3390/s21227758
    Polyvinyl alcohol (PVA)-based magnetorheological plastomer (MRP) possesses excellent magnetically dependent mechanical properties such as the magnetorheological effect (MR effect) when exposed to an external magnetic field. PVA-based MRP also shows a shear stiffening (ST) effect, which is very beneficial in fabricating pressure sensor. Thus, it can automatically respond to external stimuli such as shear force without the magnetic field. The dual properties of PVA-based MRP mainly on the ST and MR effect are rarely reported. Therefore, this work empirically investigates the dual properties of this smart material under the influence of different solvent compositions (20:80, 40:60, 60:40, and 80:20) by varying the ratios of binary solvent mixture (dimethyl sulfoxide (DMSO) to water). Upon applying a shear stress with excitation frequencies from 0.01 to 10 Hz, the storage modulus (G') for PVA-based MRP with DMSO to water ratio of 20:40 increases from 6.62 × 10-5 to 0.035 MPa. This result demonstrates an excellent ST effect with the relative shear stiffening effect (RSTE) up to 52,827%. In addition, both the ST and MR effect show a downward trend with increasing DMSO content to water. Notably, the physical state of hydrogel MRP could be changed with different solvent ratios either in the liquid-like or solid-like state. On the other hand, a transient stepwise experiment showed that the solvent's composition had a positive effect on the arrangement of CIPs within the matrix as a function of the external magnetic field. Therefore, the solvent ratio (DMSO/water) can influence both ST and MR effects of hydrogel MRP, which need to be emphasized in the fabrication of hydrogel MRP for appropriate applications primarily with soft sensors and actuators for dynamic motion control.
  16. Fulltext Influence of the Degumming Process Parameters on the Formation of Glyceryl Esters and 3-MCPDE in Refined Palm Oil: Optimization and Palm Oil Quality Analyses
    Nidzam MS, Hossain MS, Ismail N, Abdul Latip R, Mohammad Ilias MK, Mobin Siddique MB, et al.
    Foods, 2022 Jan 05;11(1).
    PMID: 35010250 DOI: 10.3390/foods11010124
    The presence of glyceryl esters (GE) and 3-monochloropropane-1,2-diol esters (3-MCPDE) in refined, bleached, and deodorized (RBD) palm oil is severely concerning to the palm oil consumer. In the present study, the influence of the phosphoric acid degumming process on the formation of GE and 3-MCDE and in the RBD palm oil was determined with varying the acid dose (0.03-0.06 wt%), temperature (70-100 °C), and reaction time (15-45 min). The experimental conditions of the acid degumming process were designed following the central composite design of experiments, and they were optimized using Response Surface Methodology (RSM) based on the minimal formation of GE and 3-MCDE in the RBD palm oil. The optimal experimental conditions of the acid degumming process were a reaction time of 30 min, phosphoric acid concentration of 0.06 wt%, and temperature of 90 °C. Under these experimental conditions, the minimal GE and 3-MCDE formation in RBD palm oil were determined to be 0.61 mg/kg and 0.59 mg/kg; respectively. Several analytical methods were employed to determine RBD palm oil quality, including color, phosphorus, free fatty acids (FFAs), peroxide values, and fatty acid properties. It was found that the phosphoric acid degumming of CPO effectively removed the phosphorus and hydroperoxide content without conceding the quality of palm oil.
  17. Sources and management of marine litter pollution along the Bay of Bengal coast of Bangladesh
    Islam MS, Phoungthong K, Islam ARMT, Ali MM, Ismail Z, Shahid S, et al.
    Mar Pollut Bull, 2022 Dec;185(Pt B):114362.
    PMID: 36410195 DOI: 10.1016/j.marpolbul.2022.114362
    Marine debris is often detected everywhere in the oceans after it enters the marine ecosystems from various sources. Marine litter pollution is a major threat to the marine ecosystem in Bangladesh. A preliminary study was conducted to identify the sources of marine litter (plastics, foamed plastic, clothes, glass, ceramic, metals, paper, and cardboard) along the Bay of Bengal coast. From the observations, the range of abundance of the collected marine litter was 0.14-0.58 items/m2. From the ten sampling sites, the highest amount of marine litter was observed for aluminium cans (3500), followed by plastic bottles (3200). The spatial distribution pattern indicated that all the study areas had beach litter of all types of materials. The present investigation showed that plastics were the dominating pollutants in the marine ecosystem in Bangladesh. The clean-coast index (CCI) value indicated that the Cox's Bazar coast was clean to dirty class. The abundance, distribution, and pollution of marine litter along the coastal belts pose a potential threat to the entire ecosystem. This study will help come up with ways to manage and get rid of marine litter along the coast in an effective way.
  18. Genetic and phenotype recovery of Ananas comosus var. MD2 in response to ionizing radiation
    Ma S, Mohd Raffi AN, Rosli MA, Mohd Zain NA, Ibrahim MH, Karsani SA, et al.
    Sci Rep, 2023 Jan 05;13(1):182.
    PMID: 36604574 DOI: 10.1038/s41598-022-26745-3
    Due to their sessile nature, plants are exposed to various environmental stressors such as exposure to high levels of harmful ultraviolet (UV), ionizing, and non-ionizing radiations. This exposure may result in various damages, ranging from DNA and chromosomal aberrations to phenotypic abnormalities. As an adaptation, plants have evolved efficient DNA repair mechanisms to detect and repair any damage caused by exposure to these harmful stressors to ensure their survival. In this study, the effects of gamma radiation (as a source of ionizing radiation) on clonal Ananas comosus var. MD2 was evaluated. The morphology and physiology of the clonal plantlets before and after exposure to gamma radiation were monitored at specific time intervals. The degree of genetic variation between the samples pre- and post-irradiation was also analyzed by using inter-simple sequence repeat (ISSR) markers. The resulting data revealed that the heights of the irradiated plantlets were significantly reduced (compared to control), but improved with the recovery period. Irradiated samples also exhibited relatively good photosynthetic efficiency that further improved as the plantlets recover. These observations were supported by the ISSR analysis, where the genetic dissimilarities between the irradiated samples and control were reduced by 0.1017, after 4 weeks of recovery. Overall, our findings suggested that the phenotype recovery of the clonal A. comosus var. MD2 plantlets was contributed by their ability to detect and repair the DNA lesions (as exemplified by the reduction in genetic dissimilarity after 4 weeks) and hence allow the plantlets to undergo phenotype reversion to normal plant stature.
  19. Fulltext Knowledge, attitudes, and practices regarding Crimean-Congo hemorrhagic fever among general people: A cross-sectional study in Pakistan
    Jamil H, Din MFU, Tahir MJ, Saqlain M, Hassan Z, Khan MA, et al.
    PLoS Negl Trop Dis, 2022 Dec;16(12):e0010988.
    PMID: 36480553 DOI: 10.1371/journal.pntd.0010988
    BACKGROUND: Crimean-Congo hemorrhagic fever (CCHF) continues to pose a serious threat to the fragile healthcare system of Pakistan with a continuous increase of morbidity and mortality. The present study aimed to assess the knowledge, attitudes, and practices regarding CCHF among general people who resided in Pakistan.

    METHODS: An online cross-sectional survey design was applied, and a convenience sampling technique was used to recruit 1039 adult people from Pakistan. Data were collected from September 08 to October 12, 2021. The questionnaire consisted of a total of 32 questions in four parts assessing socio-demographics, as well as knowledge, attitudes, and practices regarding CCHF. All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS), and logistic regression analyses were performed to determine the factors associated with good knowledge, positive attitudes, and good practices.

    RESULTS: Alarmingly, 51.5% of participants heard about CCHF infection before administering the survey. Among these, 20.2%, 33.3%, and 48.2% of the study participants had demonstrated good knowledge, positive attitudes, and good practices, respectively. Binary logistic regression analysis revealed that education and income status had a significant impact on knowledge and attitudes (p<0.05). Similarly, the mean attitude scores differed significantly by age, education, and income status (p<0.05).

    CONCLUSIONS: The findings reflected inadequate levels of knowledge, attitudes, and practices regarding CCHF among general people in Pakistan which may regard as lower than expected. As CCHF is a highly contagious disease, it's urgent to initiate a comprehensive approach to handle the situation before it spreads further in Pakistan.

  20. Fulltext Evaluation of allelopathic effects of Parthenium hysterophorus L. methanolic extracts on some selected plants and weeds
    Bashar HMK, Juraimi AS, Ahmad-Hamdani MS, Uddin MK, Asib N, Anwar MP, et al.
    PLoS One, 2023;18(1):e0280159.
    PMID: 36608038 DOI: 10.1371/journal.pone.0280159
    Herbicides made from natural molecules are cost-effective and environmentally friendly alternatives to synthetic chemical herbicides for controlling weeds in the crop field. In this context, an investigation was carried out to ascertain the allelopathic potential of Parthenium hysterophorus L. as well as to identify its phenolic components which are responsible for the allelopathic effect. During the observation, the rate of germination and seedlings' growth of Vigna subterranea (L.) Verdc, Raphanus sativus (L.) Domin, Cucurbita maxima Duchesne., Cucumis sativus L., Solanum lycopersicum L., Capsicum frutescens L., Zea mays L., Abelmoschus esculentus (L.) Moench, Daucus carota L., Digitaria sanguinalis (L.) Scop and Eleusine indica (L.) Gaertn were investigated by using methanol extracts, isolated from leaf, stem and flower of P. hysterophorus. Six concentrations (i.e., 25, 50, 75, 100, and 150 g L-1) of methanol extracts were isolated from P. hysterophorus leaf, stem and flower were compared to the control (distilled water). It was also observed that the concentration of methanol extracts (isolated from P. hysterophorus leaf, stem, and flower) while increased, the rate of seed germination and seedling growth of both selected crops and weeds decreased drastically, indicating that these methanol extracts have allelopathic potential. The allelopathic potential of P. hysterophorus leaf extraction (811) was found higher than the extraction of the stem (1554) and flower (1109), which is confirmed by EC50 values. The principal component analysis (PCA) was also used to re-validate the allelopathic potentiality of these methanol extracts and confirmed that Raphanus sativus, Solanum lycopersicum, Capsicum frutescens, Abelmoschus esculentus, Daucus carota, Digitaria sanguinalis, and Eleusine indica were highly susceptible to allelochemicals of P. hysterophorus. Besides these, the LC-MS analysis also revealed that the P. hysterophorus leaf extract contained 7 phenolic compounds which were responsible for the inhibition of tested crops and weeds through allelopathic effect. The results of the current study revealed that the leaf of P. hysterophorus is a major source of allelopathic potential on crops and weeds and which could be used as a valuable natural herbicide in the future for the sustainability of crop production through controlling weeds.
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