Browse publications by year: 2018

  1. ELTurk M, Abdullah R, Rozainah MZ, Abu Bakar NK
    Mar Pollut Bull, 2018 Nov;136:1-9.
    PMID: 30509789 DOI: 10.1016/j.marpolbul.2018.08.063
    This study was carried out to evaluate the distribution, enrichment and ecological risk of heavy metals (arsenic (As), zinc (Zn), manganese (Mn), copper (Cu) and lead (Pb)) concentration in Kuala Selangor estuary at the Kuala Selangor Nature Park. The results suggested that As and Pb in sediment were as high as the background value, suggesting the presence of anthropogenic contamination. The risk assessment of sediment Igeo, CD, and PERI, on the other hand, showed low risk of heavy metals in Kuala Selangor estuary. Meanwhile, risk assessment code (RAC) results showed that Mn, As and Zn presented medium to high level of environmental risk. The translocation factor and bioaccumulation factors of heavy metal concentration by mangrove vegetation showed a variety of trends, which indicates the different partitioning and uptake ability of heavy metal in the tissues of different mangrove species. Therefore, underscores the importance of preserving the high diversity of mangroves at securing the health and productivity of the coastal region. These results may play a critical role in facilitating decision makers in managing the sustainability of mangrove forests.
    MeSH terms: Ecology; Environmental Monitoring/methods*; Malaysia; Water Pollutants, Chemical/analysis*; Risk Assessment; Geologic Sediments/chemistry; Metals, Heavy/analysis*; Wetlands*; Estuaries*
  2. Praveena SM, Shaifuddin SNM, Akizuki S
    Mar Pollut Bull, 2018 Nov;136:135-140.
    PMID: 30509794 DOI: 10.1016/j.marpolbul.2018.09.012
    This study aims understand microplastics from personal care and cosmetic products in Malaysia via quantification and characterization of microplastics together with emission estimation to marine environment. A total of 214 respondents from all over Malaysia were surveyed with identification of top ten personal care and cosmetic products usage. Particles found in facial cleaner/scrub and toothpaste were colored and colorless with majority of granular shapes. Particles in toothpaste were found between 3 and 145 μm while particles in facial cleaner/scrub were found to be between 10 and 178 μm, stipulating the presence of microplastics. Plastic polymers (LDPE and polypropylene) were found in all facial cleaner/scrub samples while only plastic polymers (LDPE) were present in toothpaste sample G. A total of 0.199 trillion microplastics are expected to be released annually to marine environment in Malaysia. Personal care and cosmetic products are seen as one of the microplastics sources for Malaysia and worldwide.
    MeSH terms: Cosmetics; Environmental Monitoring; Malaysia; Plastics; Polypropylenes; Surveys and Questionnaires; Toothpastes; Polyethylene
  3. Besser K, Malyon GP, Eborall WS, Paro da Cunha G, Filgueiras JG, Dowle A, et al.
    Nat Commun, 2018 12 03;9(1):5125.
    PMID: 30510200 DOI: 10.1038/s41467-018-07575-2
    Woody (lignocellulosic) plant biomass is an abundant renewable feedstock, rich in polysaccharides that are bound into an insoluble fiber composite with lignin. Marine crustacean woodborers of the genus Limnoria are among the few animals that can survive on a diet of this recalcitrant material without relying on gut resident microbiota. Analysis of fecal pellets revealed that Limnoria targets hexose-containing polysaccharides (mainly cellulose, and also glucomannans), corresponding with the abundance of cellulases in their digestive system, but xylans and lignin are largely unconsumed. We show that the limnoriid respiratory protein, hemocyanin, is abundant in the hindgut where wood is digested, that incubation of wood with hemocyanin markedly enhances its digestibility by cellulases, and that it modifies lignin. We propose that this activity of hemocyanins is instrumental to the ability of Limnoria to feed on wood in the absence of gut symbionts. These findings may hold potential for innovations in lignocellulose biorefining.
    MeSH terms: Animals; Cellulose/metabolism; Diet; Digestion/physiology; Feces/chemistry; Hemocyanin/metabolism*; Lignin/metabolism*; Microscopy, Electron, Scanning; Wood/parasitology*; Xylans/metabolism; Isopoda/metabolism; Isopoda/physiology*; Gastrointestinal Tract/metabolism; Gastrointestinal Tract/physiology*; Gastrointestinal Tract/ultrastructure; Microscopy, Electron, Transmission
  4. Antonova SV, Haffke M, Corradini E, Mikuciunas M, Low TY, Signor L, et al.
    Nat Struct Mol Biol, 2018 12;25(12):1119-1127.
    PMID: 30510221 DOI: 10.1038/s41594-018-0156-z
    TFIID is a cornerstone of eukaryotic gene regulation. Distinct TFIID complexes with unique subunit compositions exist and several TFIID subunits are shared with other complexes, thereby conveying precise cellular control of subunit allocation and functional assembly of this essential transcription factor. However, the molecular mechanisms that underlie the regulation of TFIID remain poorly understood. Here we use quantitative proteomics to examine TFIID submodules and assembly mechanisms in human cells. Structural and mutational analysis of the cytoplasmic TAF5-TAF6-TAF9 submodule identified novel interactions that are crucial for TFIID integrity and for allocation of TAF9 to TFIID or the Spt-Ada-Gcn5 acetyltransferase (SAGA) co-activator complex. We discover a key checkpoint function for the chaperonin CCT, which specifically associates with nascent TAF5 for subsequent handover to TAF6-TAF9 and ultimate holo-TFIID formation. Our findings illustrate at the molecular level how multisubunit complexes are generated within the cell via mechanisms that involve checkpoint decisions facilitated by a chaperone.
    MeSH terms: HeLa Cells; Humans; Models, Molecular*; Mass Spectrometry; Transcription, Genetic; Crystallography, X-Ray; Transcription Factor TFIID/metabolism; Transcription Factor TFIID/chemistry*; TATA-Binding Protein Associated Factors/chemistry; Chaperonin Containing TCP-1/metabolism; Chaperonin Containing TCP-1/physiology*; Protein Domains
  5. Salim NA, Muttlib NAA, Alawi R, Rahman NA, Ariffin Z
    Acta Stomatol Croat, 2018 Sep;52(3):218-226.
    PMID: 30510297 DOI: 10.15644/asc52/3/5
    Objective: This study aimed to compare the difference in marginal dye penetration between everStick, Parapost XP, Parapost fiber white and control groups under gradual loading.

    Materials and Methods: Sixty-eight human maxillary permanent incisors were divided into four groups. Each specimen was endodontically treated with step-back technique and prepared for each post system according to experimental groups, subsequently cemented in the canal. Composite resin cores were built and laboratory fabricated metal crowns were cemented. All specimens except those in the control group were subjected to thermal cycling. All groups were subjected to gradual loading from 0N-50N for 100 cycles. Specimens were sectioned transversely and the depths of dye penetration along the post were measured. Data were entered in SPSS ver. 22 and analyzed using two-way ANOVA test.

    Results: There was no significant difference in marginal dye penetration between each group (p-value>0.05). However, there was a significant difference in percentage of marginal dye penetration between all groups (p-value<0.05); post-hoc comparison showed significant difference between Fiber White and Control groups (p-value=0.009).

    Conclusion: All the groups showed dye penetration but the percentage was significant only between Parapost Fiber White and the control groups.

    MeSH terms: Analysis of Variance; Composite Resins; Humans; Incisor; Maxilla; Metals; Control Groups
  6. Amin F, Khan S, Shah SMH, Rahim H, Hussain Z, Sohail M, et al.
    Drug Des Devel Ther, 2018;12:3855-3866.
    PMID: 30510401 DOI: 10.2147/DDDT.S183534
    Background: The obnoxious bitter taste of orally taken antibiotics is one of the biggest problems in the treatment of children. The pediatric population cannot tolerate the bitter taste of drugs and vomit out which ultimately leads to suboptimal therapeutic value, grimace and mental stress so it is the challenging task for the formulation scientists to formulate a palatable formulation particularly to overcome address the issue.

    Purpose of study: The study aimed to mask and evaluate the unpleasant bitter taste of azithro-mycin (AZ) in the dry suspension dosage form by physisorption technique.

    Materials and methods: AZ was selected as an adsorbent and titanium dioxide nanoparticles as adsorbate. The AZ nanohybrids (AZN) were prepared by treating fixed amount of adsorbent with a varied amount of adsorbate, prepared separately by dispersing it in an aqueous medium. The mixture was sonicated, stirred followed by filtration and drying. The AZN produced were characterized by various techniques including scanning electron microscopy (SEM), energy dispersive X-rays (EDX), powder X-ray diffraction (PXRD), HPLC and Fourier-transformed infrared (FTIR). The optimized nanohybrid was blended with other excipients to get stable and taste masked dry suspension dosage form.

    Results: The results confirmed the adsorption of titanium dioxide nanoparticles on the surface of AZ. The fabricated optimized formulation was subjected for taste masking by panel testing and accelerated stability studies. The results showed a remarkable improvement in bitter taste masking, inhibiting throat bite without affecting the dissolution rate. The product showed an excellent stability both in dry and reconstituted suspension. The optimized formulation of AZN and was found stable when subjected to physical and chemical stability studies, this is because of short and single step process which interns limits the exposure of the product to various environmental factors that could potentially affect the stability of the product. The dissolution rate of the optimized formulation of AZN was compared with its marketed counterpart, showing the same dissolution rate compared to its marketed formulation.

    Conclusion: The current study concludes that, by fabricating AZ-titanium nanohybrids using physisorption can effectively mask the bitter taste of the drug. The palatability and stability of azithromycin formulation was potentially enhanced without affecting its dissolution rate.

    MeSH terms: Adsorption; Anti-Bacterial Agents/pharmacology*; Anti-Bacterial Agents/chemistry; Humans; Molecular Conformation; Particle Size; Surface Properties; Taste/drug effects*; Titanium/pharmacology*; Titanium/chemistry; Azithromycin/pharmacology*; Azithromycin/chemistry; Nanoparticles/chemistry*; Healthy Volunteers
  7. Bunmark W, Jinatongthai P, Vathesatogkit P, Thakkinstian A, Reid CM, Wongcharoen W, et al.
    Front Pharmacol, 2018;9:1322.
    PMID: 30510510 DOI: 10.3389/fphar.2018.01322
    Background: Patients undergoing percutaneous coronary intervention (PCI) who require anticoagulant therapy are at increased risk of bleeding. The optimal regimen for these patients is uncertain. This study aimed to compare safety and efficacy of antithrombotic regimens used in patients undergoing PCI with concomitant anticoagulant therapy. Methods: A systematic review and network meta-analysis was performed among studies comparing antithrombotic regimens for anticoagulated patients undergoing PCI. The primary outcome of interest was major bleeding. The secondary outcomes were coronary events. The reference intervention was classic triple therapy (aspirin plus clopidogrel plus VKA). Cluster rank incorporating risk (major bleeding) and benefit (all-cause death) was performed to identify the most appropriate regimen(s). Results: There were 3 RCTs (6 interventions) and 29 non-RCTs (8 interventions) that met the inclusion criteria with 22,179 patients. Network meta-analysis of RCTs indicated that dual therapy (DT), either with vitamin K antagonist (VKA) or direct anticoagulant (DOAC) plus an antiplatelet, significantly reduced the risk of major bleeding compared to triple therapy (TT) [pooled RR of 0.51 (0.30-0.87) and 0.68 (0.49-0.94), respectively]. In addition, VKA-DT significantly reduced the risk of all-cause death compared to TT [pooled RR of 0.40 (0.17-0.93)]. Results from network meta-analysis of non-RCT paralleled that of RCTs. No significant differences of coronary events were found. Conclusions: In conclusion, for anticoagulated patients undergoing PCI, dual therapy, either with warfarin or DOAC plus an antiplatelet, should be considered due to its optimal balance on efficacy and safety.
    MeSH terms: Anticoagulants; Aspirin; Hemorrhage; Humans; Risk; Ticlopidine; Vitamin K; Warfarin; Percutaneous Coronary Intervention; Network Meta-Analysis
  8. Bong WC, Savage G
    Food Sci Nutr, 2018 Nov;6(8):2015-2019.
    PMID: 30510702 DOI: 10.1002/fsn3.706
    The total, soluble, and insoluble oxalate contents of fresh and wok-fried bitter gourd (Momordica charantia) fruits were extracted and measured using HPLC chromatography. Frozen bitter gourds were imported from Vietnam, and two cultivars characteristic of bitter gourd fruits grown in India and Malaysia were grown locally in the North Island of New Zealand. The mean total oxalate contents of ripe fruits from Vietnam, India, and Malaysia were 85.90 ± 8.60 mg/100 g wet matter (WM), while the mean total oxalates fell to 88.06 ± 0.95 mg/100 g FM when the fruits were wok-fried. The mean soluble oxalate content of the total oxalate was 54.42% of the ripe fruits and 58.14% of the wok-fried fruits. The three cultivars of bitter gourds were processed into juice by the addition of standard ingredients and then processed through a screw press to remove excess fiber. The final juices had an overall mean value of 27.11 mg of total oxalates/100 g WM; the mean soluble oxalate content was 85.5% of the total, which was much higher than that measured in the cooked gourds (mean 70.7%).
  9. Michael NDB, Tuan Jaffar TN, Hussein A, Wan Hitam WH
    Cureus, 2018 Sep 24;10(9):e3352.
    PMID: 30510863 DOI: 10.7759/cureus.3352
    Vaccination-induced optic neuritis is not common. The development of optic neuritis following various vaccinations have been reported, suggesting a possible association between optic neuritis and vaccination. Of those reported cases, influenza vaccines have been the most common. Although rare, those patients who developed optic neuritis following HPV vaccination also presented with other central nervous system (CNS) demyelinating syndromes, especially following a booster dose. We present a rare case of simultaneous isolated bilateral optic neuritis following the first dose of an HPV vaccination in a young child. She received treatment with a systemic corticosteroid that resulted in a good clinical outcome without developing any demyelinating disease.
    MeSH terms: Adrenal Cortex Hormones; Child; Demyelinating Diseases; Female; Humans; Influenza Vaccines; Optic Neuritis; Syndrome; Vaccination; Papillomavirus Vaccines
  10. Talib I, Sundaraj K, Lam CK, Sundaraj S
    J Musculoskelet Neuronal Interact, 2018 12 01;18(4):446-462.
    PMID: 30511949
    This systematic review aims to categorically analyses the literature on the assessment of biceps brachii (BB) muscle activity through mechanomyography (MMG). The application of our search criteria to five different databases identified 319 studies. A critical review of the 48 finally selected records, revealed the diversity of protocols and parameters that are employed in MMG-based assessments of BB muscle activity. The observations were categorized into the following: muscle torque, fatigue, strength and physiology. The available information on the muscle contraction protocol, sensor(s), MMG signal parameters and obtained results were then tabulated based on these categories for further analysis. The review affirms that - 1) MMG is suitable for skeletal muscle activity assessment and can be employed potentially for further investigation of the BB muscle activity and condition (e.g., force, torque, fatigue, and contractile properties), 2) a majority of the records focused on static contractions of the BB, and the analysis of dynamic muscle contractions using MMG is thus a research gap, and 3) very few studies have focused on the analysis of BB muscle activity under externally stimulated contractions. Taken together, the findings of this review on BB activity assessment using MMG affirm the potential of MMG as an alternative tool.
    MeSH terms: Biomechanical Phenomena/physiology; Electromyography/methods*; Humans; Muscle Contraction/physiology*; Muscle, Skeletal/physiology*; Muscle Fatigue/physiology*
  11. Nasaruddin RR, Yao Q, Chen T, Hülsey MJ, Yan N, Xie J
    Nanoscale, 2018 Dec 04.
    PMID: 30512030 DOI: 10.1039/c8nr07197g
    Quasi-homogeneous ligand-protected gold nanoclusters (Au NCs) with atomic precision and well-defined structure offer great opportunity for exploring the catalytic nature of nanogold catalysts at a molecular level. Herein, using real-time electrospray ionization mass spectrometry (ESI-MS), we have successfully identified the desorption and re-adsorption of p-mercaptobenzoic acid (p-MBA) ligands from Au25(p-MBA)18 NC catalysts during the hydrogenation of 4-nitrophenol in solution. This ligand dynamic (desorption and re-adsorption) would initiate structural transformation of Au25(p-MBA)18 NC catalysts during the reaction, forming a mixture of smaller Au NCs (Au23(p-MBA)16 as the major species) at the beginning of catalytic reaction, which could further be transformed into larger Au NCs (Au26(p-MBA)19 as the major species). The adsorption of hydrides (from NaBH4) is identified as the determining factor that could induce the ligand dynamic and structural transformation of NC catalysts. This study provides fundamental insights into the catalytic nature of Au NCs, including catalytic mechanism, active species and stability of Au NC catalysts during a catalytic reaction.
    MeSH terms: Adsorption; Catalysis; Gold; Hydrogenation; Ligands; Nitrophenols; Spectrometry, Mass, Electrospray Ionization
  12. Lo TS, Chua S, Tan YL, Patrimonio MC, Pue LB
    PLoS One, 2018;13(12):e0207375.
    PMID: 30513097 DOI: 10.1371/journal.pone.0207375
    OBJECTIVE: To compare the ultrasonographic positional changes of mid-urethral sling(MUS) tape in relation to symphysis pubis, and the different clinical outcomes among women who underwent MUS insertion with MiniArcTM or MonarcTM for the treatment of stress urinary incontinence 3 years after.

    MATERIALS AND METHODS: A retrospective follow-up study on patients with clinically confirmed stress urodynamic incontinence and urodynamic stress incontinence who had undergone MiniArc or Monarc surgery. Data regarding preoperative evaluation, intraoperative complications and post-operative follow-ups were collated. Main outcome is to determine the change in position of the sling through measurement of the x- and y-axis at rest and during Valsalva maneuver using the 3D introital ultrasound.

    RESULTS: A total of 138 patients were evaluated, 82 belonged to Monarc and 56 to MiniArc. At 3years, objective and subjective cure rates for MiniArc and Monarc were comparable (88%, 91%; p>0.05; 83%, 89%, p>0.05 respectively). Ultrasonographic changes between MiniArc and Monarc from 6 months to 3 years, showed MiniArc to exhibit significant movement in both x- [3.0 ±0.4 mm vs. 2.2 ±0.3 mm (p = 0.02) at rest; 2.6 ±0.3 mm vs. 1.6 ±0.3 mm (p<0.001) during valsalva] and y-axis [3.5 ±0.5 mm vs. 2.0 ±0.3 mm (p<0.001) at rest; 3.3 ±0.5 mm vs. 2.9 ±0.3 mm (p = 0.037) during Valsalva]. The mobility of MiniArc was significantly more than Monarc from rest to Valsalva (1.1 ±0.4 mm vs. 0.3 ±0.3 mm, p = 0.001). Tightness of the sling assessed from the major and minor axis of the urethral core had no significant difference in both groups at rest and during Valsalva. Urethral kinking percentage and the location of the sling did not yield statistical difference.

    CONCLUSION: Maintenance of continence rates of mid-urethral slings depends on the compressive effect of the sling on the urethra, urethral kinking, and sling fixation. From 6months to 3 years, MiniArc changed its position in both x- and y-axis over time, which the authors attribute to loosening of the anchoring mechanism since no clinical relevance could be sought.

    MeSH terms: Female; Follow-Up Studies; Humans; Male; Middle Aged; Postoperative Period; Ultrasonography; Urinary Incontinence, Stress/surgery*; Treatment Outcome; Suburethral Slings*
  13. Adipriyana, Raditianto, Rosmahaida Jamaludin, Hayati Habibah Abdul Talib
    MyJurnal
    Management is consistently facing fast-flowing and lots of changes in business, including in the inventory management. Especially for fast-moving inventories, the correct stocking, controlling, checking and safety stock calculation is highly needed to have an exquisite inventory management and to reduce the possibility of running out of inventory which leads to unavailability to meet the demand. One of the ways to overcome this is by doing an excellent and appropriate forecasting. Therefore, the objective of this concept paper is to analyse and recommend tools to improve inventory management using the appropriate time-series forecasting method. The firm studied in this study is serving its employees as customers that demand the routine items including stationeries and other routine products to support their job as auditors and consultants for its client. However, there are occasions when there is out-of-stock situation for fast-moving items, especially in the peak season period. Furthermore, the firm is only applying replenishment based on the used inventories from the previous month. Therefore, this study suggests to eliminate out-of-stock items situation by applying precaution initiatives such as time-series forecasting. This study is planned to employ 10 time-series forecasting methods such as moving average, exponential smoothing, regression analysis, Holt-Winters analysis, Seasonal analysis and Autoregressive Integrated Moving Average (ARIMA) using Risk Simulator Software. By simulating those methods, the most appropriate method is selected based on the forecasting accuracy measurement.
    MeSH terms: Consultants; Forecasting; Regression Analysis; Risk; Seasons; Software; Moclobemide
  14. Norfarah, I.R., Adlina, M., Nadia, M.E.
    ASM Science Journal, 2018;11(2):124-145.
    MyJurnal
    Oxidative stress (OXS) has been associated with many diseases such as neurodegenerative diseases, cancer, diabetes and osteoporosis as it can alter cellular components in the body. Oxidative stress can be neutralised by anti-oxidative compounds found in many natural products such as berries, turmeric and figs. The objective of this paper is to evaluate the anti-oxidative and anti-inflammatory properties of figs. Fig, or its scientific name Ficus carica (F. carica), is one of the fruits mentioned in the Quran and is known among the Malays as ‘buah tin’. Electronic databases used were Scopus, Ovid, Proquest and Science Direct. The inclusion criteria were studies that utilised the fresh, dried, juice, extract of F. carica, written in English, published within 2007 to 2017, studies carried out in tissue culture and animal studies. Anti-oxidative effect, lipid peroxidation inhibition and anti-inflammatory were the key outcomes in this review. A total of 19 studies met all the criteria. The results showed that treatment with F. carica increased anti-oxidative enzymes such as catalase, superoxide dismutase, glutathione peroxidase and decreased lipid peroxidation activity. F. carica also reported to reduce pro-inflammatory cytokines such as interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) in acute and chronic inflammation. In conclusion, F. carica exhibited anti-oxidative and anti-inflammatory properties.
  15. Azrul Ghazali, Sivadass Thiruchelvam, Kamal Nasharuddin Mustapha, Ahmad Kamal Kadir, Fatin Faiqa Norkhairi, Nora Yahya, et al.
    ASM Science Journal, 2018;11(2):117-123.
    MyJurnal
    Series of catastrophic floods that we have witnessed over the last decade in Malaysia have necessitated the adoption of reliable early warning system. Ultimate concern during any event of natural or manmade disaster would be information dissemination to lessen the disaster impact on lives and property. The Bertam Valley incident in the wee hours of 23rd October 2013 has been considered as the game changer of how we view the role of vulnerable communities in facing dam-related disasters. Empowerment of local communities has been considered as vital in disaster management, as they are often the first responders to disaster. Local Community-Based Early Warning System (CBEWS) is a smart mechanism operated by the communities. This study revolves around the actual implementation of such system in Cameron Highlands in the effort of increasing human resilience towards damrelated disasters. While establishing the system, the Bertam Valley community has received support from different individuals and organisations. It is paramount that the community develops and maintains close coordination and strong links with these stakeholders. The performance of early warning systems can be evaluated via key parameters such as timeliness, accuracy, reliability, user friendliness, flexibility, and costs & benefits.
    MeSH terms: Disasters; Environment; Humans; Maintenance; Malaysia; Reproducibility of Results; Information Dissemination; Floods
  16. Azlinda Abu Bakar, Sallehudin Sulaiman, Baharudin Omar, Rasadah Mat Ali
    ASM Science Journal, 2018;11(2):103-116.
    MyJurnal
    The adverse effects of prolonged and rampant usage of chemical insecticides in controlling the population of vector arthropod have caused the development of resistance among vector populations as well as non-target organism. Application of plant extracts could be alternative sources for mosquito control. The present study assessed larvicidal activities of methanol extracts of leaf and stem of Jacaranda mimosifolia Don (Family: Bignoniaceae), Melaleuca cajuputi Powell (Family: Myrtaceae), Tabebuia chrysantha (Jacq.) Nicholson (Family: Bignoniaceae), Tabebuia pallida (Lindl.) Miers (Family: Bignoniaceae) and Tabebuia rosea Toll (Family: Bignoniaceae) against dengue vectors, Aedes (Diptera: Culicidae) sp. Among plants tested, M. cajuputi exhibited the most effective with the highest mortality against Ae. aegypti and Ae. albopictus. Leaf extracts showed significantly higher larvicidal effects in relative to stem extracts. The findings also revealed that Ae. aegypti is the most susceptible compared to Ae. albopictus. LC50 values of M. cajuputi leaf extracts were 183.35mg/L and 191.82mg/L against Ae. aegypti and Ae. albopictus respectively. These studies suggest leaf extracts of M. cajuputi have moderate potential as larvicidal against vector larvae of Aedes mosquitoes.
    MeSH terms: Aedes; Methanol; Animals; Arthropod Vectors; Dengue; Disease Vectors; Insecticides; Larva; Mosquito Control; Plant Extracts; Myrtaceae; Bignoniaceae; Tabebuia; Melaleuca
  17. Babura, Babangida Ibrahim, Mohd Bakri Adam, Anwar Fitrianto, Abdul Rahim, A.S.
    ASM Science Journal, 2018;11(2):86-102.
    MyJurnal
    A boxplot is an exploratory data analysis (EDA) tool for a compact visual display of a distributional summary of a univariate data set. It is designed to capture all typical observations and displays the location, spread, skewness and the tail of the data. The precision of some of this functionality is considered to be more reliable for symmetric data type and thus less appropriate for skewed data such as the extreme data. Many observations from extreme data were mistakenly marked as outliers by the Tukey’s standard boxplot. A new boxplot implementation is presented which adopts a fence definition using the extent of skewness and enhances the plot with additional features such as a quantile region for the parameters of generalized extreme value (GEV) distribution in fitting an extreme data set. The advantage of the new superimposed region was illustrated in term of batch comparison of extreme samples and an EDA tool to determine search region or direction as contained in the optimisation routines of a maximum likelihood parameter estimation of GEV model. A simulated and real-life data were used to justify the advantages of the boxplot enhancement.
  18. Mohd Razali Md Razak, Zaleha Kassim
    ASM Science Journal, 2018;11(2):76-85.
    MyJurnal
    Information on feeding behaviour of tropical horseshoe crabs, Tachypleus gigas (M¨uller, 1785) is still scanty compared to Limulus polyphemus (Linnaeus, 1758). Foods condition such as decayed, sheltered and etc., would substantially influence the edibility of food by the T. gigas. However, horseshoe crabs might have specific behaviour to manipulate the foraged food. The aim of this paper was to investigate the feeding mechanism of T. gigas toward different feed conditions. Experiments were conducted inside a glass tank. A total of 30 males and females respectively were introduced to five different natural potential feeds, namely, gastropods (Turritella sp.), crustacean (Squilla sp.), fish (Lates calcarifer ), bivalve (Meretrix meretrix ) and polychaete (Nereis sp.). We have manipulated the condition of introduced feed based on the several potential foods conditions in nature such as sheltered (protected with shell, hard outer skin or host tube), unsheltered and decayed before introduced the feeds to the crabs. In present study, female crabs took shorter response period towards surrounding feed compared to males. Overall, they prefer to consume freshly dead feeds and would totally reject the sheltered feeds, such as, shell, hard outer skin and tube host. Male crabs have particular feeding behaviours to manipulate the edibility of the decayed feeds. Detailed experiments on the feeding mechanism of T. gigas could provide more information on their foraging activity in the wild.
  19. Sofian Ibrahim, Keong, Chai Chee, Ratnam, Chantara Thevy, Khairiah Badri
    ASM Science Journal, 2018;11(2):67-75.
    MyJurnal
    Radiation pre-vulcanised natural rubber latex (RVNRL) prepared by using gamma irradiation technique has many advantages over the conventionally prepared sulphur pre-vulcanised natural rubber latex (SPVL). Despite the fact that many potential latex dipped products can be made from RVNRL, little effort was made to fully commercialise the products because of the inferior strength of RVNRL products compared to SPVL products. An attempt was made to improve the tensile strength of RVNRL by combining both radiation and peroxide vulcanisation in order to ensure that the products will not tear or fail, and has sufficient stretch. Hexanediol diacrylate (HDDA) plays the main role as sensitizer during radiation vulcanisation and tert-butyl hydroperoxide (t-BHPO) as the co-sensitizer in peroxide vulcanisation. Pre-vulcanised natural rubber latex dipped films via hybrid radiation and peroxidation vulcanisations obtained showed tensile strength of 26.7 MPa, an increment of more than 15% compared to controlled film (22.5 MPa). Besides, the crosslink percentage of the rubber films also showed around 5% increment from 90.7% to 95.6%.
    MeSH terms: Acrylates; Latex; Peroxides; Rubber; Sulfur; Tensile Strength; tert-Butylhydroperoxide; Lacerations
External Links