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  1. Synthesis of ZnO nanoparticles with chitosan as stabilizing agent and their antibacterial properties against Gram-positive and Gram-negative bacteria
    Yusof NAA, Zain NM, Pauzi N
    Int J Biol Macromol, 2019 Mar 01;124:1132-1136.
    PMID: 30496864 DOI: 10.1016/j.ijbiomac.2018.11.228
    Antibacterial activity of zinc oxide (ZnO) nanoparticles have received significant interest, particularly by the implementation of nanotechnology to synthesize particles in nanometer region. ZnO nanoparticles were successfully synthesized through microwave heating by using chitosan as a stabilizing agent and characterized by UV-vis, FTIR, XRD and FESEM-EDX. The aim of the present study is to determine the antibacterial activity of ZnO nanoparticles against Gram-positive bacterium Staphylococcus aureus (S. aureus) and Gram-negative bacterium Escherichia coli (E. coli). The antibacterial effect of ZnO nanoparticles was investigated for the inhibition zone and inactivation of cell growth. The absorption of ZnO nanoparticles was found to be around 360 nm. FTIR results showed the stretching mode of ZnO nanoparticles at 475 cm-1 of the absorption band. EDX results indicated that ZnO nanoparticles have been successfully formed with an atomic percentage of zinc and oxygen at 23.61 and 46.57% respectively. X-ray diffraction result was confirmed the single-phase formation of ZnO nanoparticles and the particle sizes were observed to be around 50 to 130 nm. The results showed that ZnO nanoparticles have displayed inhibition zone of 16 and 13 mm against S. aureus and E. coli respectively. Gram-negative bacteria seemed to be more resistant to ZnO nanoparticles than Gram-positive bacteria.
  2. Fulltext Down-regulation of steroidogenesis-related genes and its accompanying fertility decline in streptozotocin-induced diabetic male rats: ameliorative effect of metformin
    Nna VU, Bakar ABA, Ahmad A, Mohamed M
    Andrology, 2019 01;7(1):110-123.
    PMID: 30515996 DOI: 10.1111/andr.12567
    BACKGROUND: Metformin has long been used for glycemic control in diabetic state. Recently, other benefits of metformin beyond blood glucose regulation have emerged.

    OBJECTIVES: To investigate the effect of metformin on the expression of testicular steroidogenesis-related genes, spermatogenesis, and fertility of male diabetic rats.

    MATERIALS AND METHODS: Eighteen adult male Sprague Dawley rats were divided into three groups, namely normal control (NC), diabetic control (DC), and metformin-treated (300 mg/kg body weight/day) diabetic rats (D+Met). Diabetes was induced using a single intraperitoneal injection of streptozotocin (60 mg/kg b.w.), followed by oral treatment with metformin for four weeks.

    RESULTS: Diabetes decreased serum and intratesticular testosterone levels and increased serum but not intratesticular levels of luteinizing hormone. Sperm count, motility, viability, and normal morphology were decreased, while sperm nuclear DNA fragmentation was increased in DC group, relative to NC group. Testicular mRNA levels of androgen receptor, luteinizing hormone receptor, cytochrome P450 enzyme (CYP11A1), steroidogenic acute regulatory (StAR) protein, 3β-hydroxysteroid dehydrogenase (HSD), and 17β-HSD, as well as the level of StAR protein and activities of CYP11A1, 3β-HSD, and 17β-HSD, were decreased in DC group. Similarly, decreased activities of epididymal antioxidant enzymes and increased lipid peroxidation were observed in DC group. Consequently, decreased litter size, fetal weight, mating and fertility indices, and increased pre- and post-implantation losses were recorded in DC group. Following intervention with metformin, we observed increases in serum and intratesticular testosterone levels, Leydig cell count, improved sperm parameters, and decreased sperm nuclear DNA fragmentation. Furthermore, mRNA levels and activities of steroidogenesis-related enzymes were increased, with improved fertility outcome.

    DISCUSSION AND CONCLUSION: Diabetes mellitus is associated with dysregulation of steroidogenesis, abnormal spermatogenesis, and fertility decline. Controlling hyperglycemia is therefore crucial in preserving male reproductive function. Metformin not only regulates blood glucose level, but also preserves male fertility in diabetic state.

  3. Fulltext Cytogenetic analysis of buccal cells from farmers in Tanjung Karang and Kelantan who were exposed to pesticides
    Ahmad Rohi Ghazali, Maziani Abdullah, Asmah Hamid, Asmariah Ahmad, Tava Shelan Nagapan, Ismarulyusda Ishak, et al.
    Jurnal Sains Kesihatan Malaysia, 2018;16(101):1-8.
    MyJurnal
    Pesticides and chemical fertilizers are widely used in agriculture to increase crop productivity among farmers. However, exposure to pesticides will give potential risk to human health. The aim of this study was to analyze the frequency of micronucleus (MN) and binucleus (BNu) formation in buccal cells from farmers who were exposed to pesticides using the MN assay. Buccal swabs were collected from the farmers in Tanjung Karang (n = 32) and Kelantan (n = 43) using wooden tongue depressor. A structured questionnaire was used to obtain demographic data of the farmers. Cytogenetic analysis was carried out by Acridin Orange (AO) staining 0.0025% (w/v). The frequency of MN and BNu as the biomarkers for cytogenetic damage was observed by using a fluorescence microscope. Comparison of frequency of MN and BNu is conducted in two areas namely Tanjung Karang, Selangor and Kelantan because of the agricultural activity and the type of pesticides used are different. Results showed that the frequencies of both MN and BNu among farmers in Tanjung Karang were significantly higher (p < 0.05) compared to farmers in Kelantan. Meanwhile, for the socio-demographic factors (age, smoking status, working period), MN and BNu frequencies among farmers in Tanjung Karang were also significantly higher (p < 0.05) as compared to farmers in Kelantan. While in the aspect of pesticide exposure, the frequencies of MN and BNu showed no significant difference between the frequency of pesticide spraying (p > 0.05) and the practices of PPE (Personal Protective Equipment) (p > 0.05). This may suggests that cytogenetic changes were not influenced by these factors. In addition, correlation study shows positive correlation between the frequency of MN with the pesticide exposure of farmers in Tanjung Karang (p > 0.05, r = 0.015) and Kelantan (p > 0.05, r = 0.0158). Besides, the frequency of BNu also has a positive correlation with the pesticide exposure among farmers in Tanjung Karang (p > 0.05, r = 0.036) and farmers in Kelantan (p > 0.05, r = 0.013). Hence, this present study demonstrated that exposure to pesticides increased the formation of MN and BNu among farmers and the prolonged use of pesticides may induce genotoxicity and DNA damage to human
  4. Spatial distribution trend of plankton in sungai Pulai estuary, the straits of Johor, Malaysia
    Zaleha Kassim, Kamaruzzaman Yunus, Jalal K, Ili Nabilah Jaafar, Nur Suhaila Nordin, Wan Muhamad Amir Wan Ahmad, et al.
    Sains Malaysiana, 2015;44:1257-1262.
    A spatial distribution study was carried out to investigate the influence of some environmental factors to planktons using collected samples from the Sungai Pulai estuary, near to the Singapore boarder. Six stations chosen for the field sampling were Port Tanjung Pelepas (S1), Tanjung Bin Charcoal Plant (S2), seagrasses of Pulau Merambong (S4) and SecondLink Bridge (S5) and mangrove areas (S3, S6). There is no significant difference of phytoplankton abundance (p>0.05) between stations. Instead, it differs significantly at the level of p<0.05; p= 0.0001 (Two tailed, t=14.10 df=34) between sampling session. In contrast, there is a significant difference of zooplankton abundance (p<0.05) in the sampling stations (χ2 = 17.3,(5)), but there is no significant difference (p>0.05; p=0.8966) between the sampling session (Two tailed, t=0.1310, df=34). Biplot analysis shows that most species are associated with the stations except for Protoperidinium sp., Lithodesmia sp. and Alexendrium sp. Copepod species including Microcalanus sp., Calanus sp. and Temora sp. are associated with S5. Paracalanus sp., Euterpina sp., Tigriopus sp., Oithona sp. and Pseudocalanus sp. are associated with S1, S2 and S4. The planktons are correlated with the temperature (Pearson’s correlation, r2=-0.897) and salinity (Pearson’s correlation, r2=0.9416) in March but no correlation is found in November sampling session. The results indicated the important role of certain environmental factors, namely the salinity and temperature to the distribution of the planktons in Sungai Pulai estuary.
  5. Therapeutic effect of Vitamin E in preventing bone loss: An evidence-based review
    Nazrun Shuid A, Das S, Mohamed IN
    Int J Vitam Nutr Res, 2019 Nov;89(5-6):357-370.
    PMID: 30856080 DOI: 10.1024/0300-9831/a000566
    The present review explored the anti-inflammatory and immunomodulatory properties of vitamin E, which has protective action against osteoporosis. A systematic review of the literature was conducted to identify the published bone studies on vitamin E. The studies included inflammatory or immunology-related parameters. Medline and Scopus databases were searched for relevant studies published from 2005 till 2015. Research articles published in English and confined to the effect of vitamin E on bone were included. It is pertinent to mention that these studies took into consideration inflammatory or immunology parameters including interleukin (IL)-1, IL-6, receptor activator of nuclear factor kappa-B ligand (RANKL), inducible nitric oxide synthases (iNOS), serum amyloid A (SAA), e-selection and high-sensitivity C-reactive protein (hs-CRP). An extended literature search yielded 127 potentially relevant articles with seven articles meeting the inclusion and exclusion criteria. Another recent article was added with the total number accounting to eight. All these included literature comprised five animal studies, one in-vitro study and two human studies. These studies demonstrated that vitamin E, especially tocotrienol, was able to alleviate IL-1, IL-6, RANKL, iNOS and hs-CRP levels in relation to bone metabolism. In conclusion, vitamin E exerts its anti-osteoporotic actions via its anti-inflammatory and immunomodulatory effects.
  6. Fulltext Tourism crises and island destinations: Experiences in Penang, Malaysia
    Ghaderi Z, Mat Som AP, Henderson JC
    Tour Manag Perspect, 2012 04 26;2:79-84.
    PMID: 32289006 DOI: 10.1016/j.tmp.2012.03.006
    Crisis management and tourism is attracting increasing attention as an industry practice and subject of academic enquiry, not least in South East Asia which has been affected by a number of severe crises in recent years. However, organisations are not always well prepared and response strategies can be deficient. The paper discusses issues of tourism crisis management with specific reference to the popular Malaysian destination of Penang. Findings are based on qualitative research consisting of semi-structured interviews with industry leaders from assorted sectors. Tourism in Penang emerges as vulnerable to regional and global events which act as a trigger for tourism crises, demanding a response in which various strategies are employed. The destination is also seen to recover fairly quickly from experiences of crises, but a well designed and formulated tourism crisis management plan under the stewardship of the public sector is necessary to mitigate further damage in the future.
  7. Fulltext Compatibilization Effect of Ionic Liquid-Based Surfactants on Physicochemical Properties of PBS/Rice Starch Blends: An Initial Study
    Shamsuri AA, Md Jamil SNA
    Materials (Basel), 2020 Apr 17;13(8).
    PMID: 32316400 DOI: 10.3390/ma13081885
    Polybutylene succinate (PBS)/rice starch (RS) blends were prepared via the hot-melt extrusion technique through the usage of a twin-screw extruder without and containing ionic liquid-based surfactants (ILbS). Two types of ILbS were used, specifically, 1-dodecyl-3-methylimidazolium trifluoromethanesulfonate, [C12mim][OTf] and 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C12mim][NTf2] were mixed into the PBS/RS blends at the different contents (0-8 wt.%). The tensile and flexural results showed that the blends containing ILbS have a high tensile extension and tensile energy compared to the blend without ILbS. The blends containing ILbS also have a high flexural extension compared with the blend without ILbS. The blends containing [C12mim][NTf2] have a significant improvement in the tensile energy (up to 239%) and flexural extension (up to 17%) in comparison with the blends containing [C12mim][OTf]. The FTIR spectra demonstrated that the presence of ILbS in the blends generated the intermolecular interactions (ion-dipole force and hydrophobic-hydrophobic interaction) between PBS and RS. The DSC results exhibited that the melting points of the prepared blends are decreased with the addition of ILbS. However, the TGA results showed that the thermal decomposition of the blends containing ILbS are higher than the blend without ILbS. The values of decomposition temperature were 387.4 °C, 381.8 °C, and 378.6 °C of PBS/RS-[C12mim][NTf2], PBS/RS-[C12mim][OTf], and PBS/RS, respectively. In conclusion, the ILbS could significantly improve the physicochemical properties of the PBS/RS blends by acting as a compatibilizer.
  8. Gene expression programming for process parameter optimization during ultrafiltration of surfactant wastewater using hydrophilic polyethersulfone membrane
    Shishegaran A, Boushehri AN, Ismail AF
    J Environ Manage, 2020 Jun 15;264:110444.
    PMID: 32217322 DOI: 10.1016/j.jenvman.2020.110444
    Surfactants are the emerging contaminant and cause a detrimental effect on the ecosystem. In this study, an attempt is made to removal anionic surfactant Sodium dodecyl sulfate (SDS) containing wastewater using hydrophilic polyvinylpyrollidone (PVP) (5-15 wt%) modified polyethersulfone (PES) ultrafiltration membrane. The influence of operating variables on membrane performance was also sequentially analyzed using tests and three numerical modeling methods such as multiple linear regression (MLR), multiple Ln-equation regression (MLnER), and gene expression programming (GEP). Contact angle value of 10 wt% PVP modified PES membrane decreased up to 23.8°, whereas the neat PES membrane is 70.7°. This study indicates that the required hydrophilic property was improved in the modified membrane. The water flux and porosity also enhanced in PVP modified PES membranes. In performance evaluation, the optimum operating variable condition of transmembrane pressure (TMP), feed concentration, and the temperature is found to be 3 bar, 100 ppm, and 25 °C, respectively. Among the models, GEP has a good correlation with experimental anionic surfactant SDS filtration data. GEP performs better than other model with respect to statistical parameter and error terms. This study provides an insight into an adaptation of novel numerical modeling methods for the prediction of membrane performance to the treatment of surfactant wastewater.
  9. The influences of basic physical properties of clayey silt and silty sand on its laboratory electrical resistivity value in loose and dense conditions
    Mohd Hazreek Zainal Abidin, Devapriya Chitral Wijeyesekera, Mohamad Faizal Tajul Baharuddin, Saiful Azhar Ahmad Tajudin, Aziman Madun, Rosli Saad, et al.
    Sains Malaysiana, 2017;46:1959-1969.
    Non-destructive test which refers to electrical resistivity method is recently popular in engineering, environmental, archaeological and mining studies. Based on the previous studies, the results on electrical resistivity interpretation were often debated due to lack of clarification and evidences in quantitative perspective. Traditionally, most of the previous result interpretations were depending on qualitative point of view which is risky to produce unreliable outcomes. In order to minimise those problems, this study has performed a laboratory experiment on soil box electrical resistivity test which was supported by an additional basic physical properties of soil test like particle size distribution test (d), moisture content test (w), density test (ρbulk) and Atterberg limit test (LL, PL and PI). The test was performed to establish a series of electrical resistivity value (ERV) with different quantity of water content for clayey silt and silty sand in loose and dense condition. Apparently, the soil resistivity value was different under loose (L) and dense (C) conditions with moisture content and density variations (silty SAND = ERVLoose: 600 - 7300 Ωm & ERVDense: 490 - 7900 Ωm while Clayey SILT = ERVLoose: 13 - 7700 Ωm & ERVDense: 14 - 8400 Ωm) due to several factors. Moreover, correlation of moisture content (w) and density (ρbulk) due to the ERV was established as follows; Silty SAND: w(L) = 638.8ρ-0.418, w(D) = 1397.1ρ-0.574, ρBulk(L) = 2.6188e-6E-05ρ, ρBulk(D) = 4.099ρ-0.07 while Clayey SILT: w(L) = 109.98ρ-0.268, w(D) = 121.88ρ-0.363, ρBulk(L) = -0.111ln(ρ) + 1.7605, ρBulk(D) = 2.5991ρ-0.037 with determination coefficients, R2 that varied from 0.5643 – 0.8927. This study was successfully demonstrated that the consistency of ERV was greatly influenced by the variation of soil basic physical properties (d, w, ρBulk, LL, PL and PI). Finally, the reliability of the ERV result interpretation can be enhanced due to its ability to produce a meaningful outcome based on supported data from basic geotechnical properties.
  10. Are sociodemographic characteristics and attitude good predictors of speeding behavior among drivers on Malaysia federal roads?
    Mohamad FF, Abdullah AS, Mohamad J
    Traffic Inj Prev, 2019;20(5):478-483.
    PMID: 31188019 DOI: 10.1080/15389588.2019.1612057
    Objective: The increasing number of road crashes and fatalities on Malaysian federal roads is a cause for concern. The main causes of road crashes and fatalities on federal roads have been attributed to the speeding behavior among drivers. As such, this research investigates the possible predictors from sociodemographic characteristics and attitudes in predicting speeding behavior among drivers on Malaysia federal roads. Methods: A face-to-face survey was conducted via purposive sampling on 300 drivers at rest areas at 6 crash hotspots on Malaysian federal roads. A set of questions related to speeding behavior was developed. The questionnaire consisted of 10 questions related to sociodemographic characteristics of the participants, 37 questions regarding attitudes toward speeding, and 1 question regarding speeding behavior. Subsequently, the sociodemographics were analyzed using binary logistic regression and the attitude variable was analyzed using factor analysis and binary logistic regression. Results: The findings from the sociodemographic data revealed that male gender, single/separated status, broad driving experience, crash experience, and leisure/vacation trip purposes emerged as significant predictors for speeding behavior. Additionally, the results of factor analysis for the attitude variable revealed 3 components: Affective, behavioral, and cognitive. These 3 components are originally derived from the ABC model of attitude (affective, behavioral, and cognitive) that was adapted in this study. Furthermore, the findings from binary logistic regression appeared consistent with the model assumption, signifying that behavioral aspects significantly influenced speeding behavior among drivers. Nevertheless, affective and cognitive components were insignificant predictors. Furthermore, strong agreement with speeding countermeasures was observed among the participants. Conclusion: In conclusion, sociodemographic characteristics and attitude have been proven to affect speeding behavior among drivers on Malaysian federal roads. The findings have important implications in designing driver risk profiles on federal roads to develop suitable countermeasures based on the 4E approach (engagement, education, enforcement, and engineering) to enhance road safety.
  11. Drivers of food waste generation: Case study of island-based hotels in Langkawi, Malaysia
    Kasavan S, Mohamed AF, Abdul Halim S
    Waste Manag, 2019 May 15;91:72-79.
    PMID: 31203944 DOI: 10.1016/j.wasman.2019.04.055
    Food waste (FW) generation from hotel operations have a significant negative impact on the environment, society and economy. Hence, the urgent need to introduce sustainable food management to reduce both FW and operational costs in hotels. The aim of this paper is to identify the drivers of FW generation and barriers to sustainable food waste management (SFWM) in island based hotels. The data were collected using in-depth interview coupled with the observations conducted at 23 selected hoteliers in Langkawi Island, Malaysia. Based on the analysis, using qualitative content analysis (QCA), eight FW drivers were identified and the drivers were classified into three categories of factors, mainly internal, external and intermediate influence. There are four FW drivers identified as internal factors that influenced the implementation of food waste management namely (1) poor hotel management and policies, (2) lack of skills in food preparation, (3) lack of facilities and FW technology and (4) non-implementation of waste audit and waste separation. For external factors, there are two FW drivers, including (5) unsustainable food consumption patterns of the customers and (6) risk of food ingredients spoilage. As for intermediate factors, two FW drivers were identified, which are (7) ineffective communication and (8) inadequate education and awareness. Findings from this study contribute towards a better understanding on the complexity of FW issues, particularly for island-based hotel sector. It was also suggested that a holistic approach with multi-stakeholders is crucial to reduce food wastage towards achieving SFWM.
  12. Fulltext Void Content, Tensile, Vibration and Acoustic Properties of Kenaf/Bamboo Fiber Reinforced Epoxy Hybrid Composites
    Ismail AS, Jawaid M, Naveen J
    Materials (Basel), 2019 Jun 28;12(13).
    PMID: 31261821 DOI: 10.3390/ma12132094
    This study aims to investigate the void content, tensile, vibration and acoustic properties of kenaf/bamboo fiber reinforced epoxy hybrid composites. The composites were made using the hand lay-up method. The weight ratios of kenaf/bamboo were 30:70, 50:50 and 70:30. Further, kenaf and bamboo composites were fabricated for the purpose of comparison. The hybridization of woven kenaf/bamboo reduced the void content. The void contents of hybrid composites were almost similar. An enhancement in elongation at break, tensile strength and modulus of hybrid composites was observed until a kenaf/bamboo ratio of 50:50. Kenaf/bamboo (50:50) hybrid composite displays the highest elongation at break, tensile strength and modulus compared to the other hybrid composites which are 2.42 mm, 55.18 MPa and 5.15 GPa, respectively. On the other hand, the highest natural frequency and damping factors were observed for Bamboo/Kenaf (30:70) hybrid composites. The sound absorption coefficient of composites were measured in two conditions: without air gap and with air gap (10, 20, 30 mm). The sound absorption coefficient for testing without air gap was less than 0.5. Introducing an air gap improved the sound absorption coefficient of all composites. Hence, hybrid kenaf/bamboo composites exhibited less void content, as well as improved tensile, vibration and acoustic properties.
  13. Occurrence and potential risk of organophosphorus pesticides in urbanised Linggi River, Negeri Sembilan, Malaysia
    Zainuddin AH, Wee SY, Aris AZ
    Environ Geochem Health, 2020 Nov;42(11):3703-3715.
    PMID: 32488800 DOI: 10.1007/s10653-020-00604-4
    The application of organophosphorus pesticides (OPPs) increased gradually because of the rise in global food demand that triggered the agriculture sector to increase the production, leading to OPP residues in the surface water. This study elucidated the presence of OPPs and estimated its ecological risk in the riverine ecosystem of the urbanised Linggi River, Negeri Sembilan, Malaysia. The OPP concentration in surface water was determined using solid-phase extraction method and high-performance liquid chromatography coupled with diode array detection. Further, the ecological risk was estimated by using the risk quotient (RQ) method. The three OPPs, i.e. chlorpyrifos, diazinon, and quinalphos were detected with mean concentrations of 0.0275 µg/L, 0.0328 µg/L, and 0.0362 µg/L, respectively. The OPPs were at high risk (in general and worst cases) under acute exposure. The estimated risk of diazinon was observed as medium for general (RQm = 0.5857) and high for worst cases (RQex = 4.4678). Notably, the estimated risk for chlorpyrifos was high for both general and worst cases (RQm = 1.9643 and RQex = 11.5643) towards the aquatic ecosystem of the Linggi River. Chronic risk of quinalphos remains unknown because of the absence of toxicity endpoints. This study presented clear knowledge regarding OPP contamination and possible risk for aquatic ecosystems. Hence, OPPs should be listed as one of the main priority contaminants in pesticide mitigation management in the future.
  14. Fulltext Preliminary result of randomised controlled trial of three different coated archwires part 2: colour change and patient perception
    Hassanin Abdulkhabeer Ali Alyassiri, Anis Farhan Kamaruddin, Noor Ayuni Ahmad Shafiai, Khoirulzariah Ismail, Norma Ab Rahman, Wan Muhamad Amir W Ahmad
    Malaysian Journal of Medicine and Health Sciences, 2019;15(109):74-79.
    MyJurnal
    Introduction: Coated archwires improve aesthetics because of the tooth-coloured appearance. However, colour change of the coated archwires have been reported in vitro. Nonetheless, little is known to what extent this colour change occurs clinically. This second part of the multi-centre, double-blind, randomised controlled trial evaluated the colour change (E*) of three coated archwires with their controls and patient perception. Methods: 84 patients who received treatment with upper and lower fixed appliance treatment were invited. Consented patients were randomised to receive one of four treatment interventions using 0.014” superelastic nickel-titanium archwires from
    (1) Orthocare (2) RMO (3) G&H, and (4) 3M Unitek® uncoated. These archwires were ligated during bonding and collected after 8th week. After removal, the digital images of the archwires were assessed for colour change using Adobe® Photoshop® software, and the CIE L*a*b* system was used to calculate the ΔE* values. Patient perception was measured using oral aesthetic subjective impact scale (OASIS) questionnaire. Results: For colour change and patient perception assessment, 132 archwires from 66 participants who had been treated with aesthetic archwires were collected. Two fractured archwires were excluded. Initial analysis revealed all three aesthetic archwires groups showed significant mean of E* with the highest was found in Orthocare (23.9), and the lowest is G&H (16.8). Post hoc comparison revealed statistically significant mean of E* in Orthocare when compared with other groups (p
  15. Suitability of heat- and freeze-killed oothecae of the American cockroach (Dictyoptera: Blattidae) as hosts for an oothecal parasitoid, Aprostocetus hagenowii (Hymenoptera: Eulophidae)
    Tee HS, Saad AR, Lee CY
    J Econ Entomol, 2010 Oct;103(5):1770-4.
    PMID: 21061978
    The objective of this study was to evaluate the suitability of heat- and freeze-killed oothecae of Periplaneta americana (L.) (Dictyoptera: Blattidae) as hosts for parasitoid Aprostocetus hagenowii (Ratzeburg) (Hymenoptera: Eulophidae). The oothecae were subjected to -20, 45, 48, 50, and 55 degrees C at different exposure times (15, 30, 45, and 60 min). The effects of heat- and freeze-killed oothecae on several biological parameters (e.g., parasitism and emergence rates, developmental times, progeny number, and sex ratio) ofA. hagenowii were determined. Embryonic development of 2-d-old oothecae was terminated by either freezing at -20 degrees C or heating at > or = 48 degrees C for > or =30 min. A. hagenowii parasitized live oothecae as well as both heat- and freeze-killed oothecae. Percentage parasitism, emergence rates, and developmental times ofA. hagenowii in both heat- and freeze-killed oothecae were not significantly different from those of the live oothecae. Both heating and freezing did not influence progeny number (male and female) and sex ratio of A. hagenowii emerged from killed oothecae.
  16. Feeding response of subterranean termites Coptotermes curvignathus and Coptotermes gestroi (Blattodea: Rhinotermitidae) to baits supplemented with sugars, amino acids, and cassava
    Castillo VP, Sajap AS, Sahri MH
    J Econ Entomol, 2013 Aug;106(4):1794-801.
    PMID: 24020295
    Feeding responses of subterranean termites Coptotermes curvignathus (Holmgren) and Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae) to bait matrices supplemented with various sugars, amino acids, and cassava were evaluated both in the laboratory and field. The results indicated that the two termite species consumed significantly different amount of filter papers that had been treated with various types and concentrations of sugars and amino acids. Based on consumption and survival data, filter papers with 3% glucose and 3% xylose were among the most consumed by C. curvignathus and C. gestroi, respectively. Both termite species consumed more of the filter papers treated with 3% casein than filter papers treated with L-alanine. Both species had a comparable survival rate compared with those in the controls. Results from laboratory and field trials on bait prototypes indicated that C. gestroi consumed more bait prototypes containing cellulose, 3% xylose, 3% casein, and cassava, whereas C curvignathus consumed more bait prototype containing cellulose, 3% glucose, and cassava, than on pure crystalline cellulose baits. Thus, with an improved and cost-effective bait formulation, a much wider control of subterranean termite colonies could be achieved.
  17. Evaluation of Aprostocetus hagenowii (Hymenoptera: Eulophidae) for the control of American cockroaches (Dictyoptera: Blattidae) in sewers and crevices around buildings
    Tee HS, Saad AR, Lee CY
    J Econ Entomol, 2011 Dec;104(6):2031-8.
    PMID: 22299367
    The objective of this study was to evaluate the potential of Aprostocetus hagenowii (Ratzeburg) (Hymenoptera: Eulophidae) to control American cockroaches, Periplaneta americana (L.) (Dictyoptera: Blattidae), in sewer manholes and in crevices around buildings. Parasitoids were released weekly for 12 wk from laboratory parasitized heat-killed oothecae, and parasitism monitored using sentinel oothecae of American cockroaches. In addition, preference of A. hagenowii for 1- to 4-wk-old oothecae was evaluated in the laboratory. A. hagenowii females showed no preference for any ootheca age. Twenty of the 30 tested females parasitized one ootheca, whereas the other 10 parasitized two oothecae. The total progeny (males, females, and total) that emerged from a single ootheca parasitized by a female was not significantly different to the total progeny that emerged from two oothecae parasitized by a female. The number of males, females, and total progeny that emerged from the second parasitized ootheca was significantly less than the number that emerged from the first parasitized ootheca. The weekly mean sentinel oothecal parasitism rate in wall crevices was 18.1 +/- 3.2% and in sewer manholes was 13.3 +/- 2.0%. The mean number of released A. hagenowii females per number of parasitized sentinel oothecae recorded in crevices was 189 +/- 18, whereas it was 428 +/- 50 in sewers. A. hagenowii females were more effective at parasitizing sentinel oothecae placed at high and middle levels in manholes than at a low level when releases were made at the midpoint of the manhole shaft.
  18. Effect of Irradiating Puparia of Oriental Fruit Fly (Diptera: Tephritidae) on Adult Survival and Fecundity for Sterile Insect Technique and Quarantine Purposes
    Yusof S, Mohamad Dzomir AZ, Yaakop S
    J Econ Entomol, 2019 12 09;112(6):2808-2816.
    PMID: 31393572 DOI: 10.1093/jee/toz217
    The aim of this study was to investigate the effect of gamma irradiation on survivability (adult emergence, sex ratio, adult longevity), fecundity (eggs hatchability, number of eggs produced), and morphological differences in the size of the ovary and testes of unirradiated and irradiated adults of Oriental fruit fly [Bactrocera dorsalis (Hendel)]. A dose of 100 Gy was determined as the minimum needed for inhibitory effects against B. dorsalis that would not deter adult emergence, sex ratio (male:female), and adult longevity, with 82.6 ±7.02, 1:1.09, and 107 ± 24.5, respectively. Doses from 50 to 400 Gy range did not completely prevent the adult emergence; however, the emergence decreased by increasing the radiation dose. Adult survivability significantly decreased among all the treatment groups of B. dorsalis, except for the 50 Gy and unirradiated flies. At a dose of 50 Gy, fertile females showed a significant reduction in fecundity by not producing eggs after mating with the sterile males. Meanwhile, the number of eggs laid decreased with increasing dose and no fertile egg was hatched starting at 100 Gy of irradiation. Testes and ovaries of 20-d old flies irradiated as pupae were smaller than those of control flies. In this study, 100 Gy was concluded as the minimum effective dose for the disinfestation and sterilization of B. dorsalis puparia. Results represent new findings used as a basis for sterile insect technique and quarantine programs for managing B. dorsalis, particularly in Malaysia.
  19. Development and validation of the knowledge and attitude regarding childhood vaccination (KACV) questionnaire among healthcare workers: the Malay version
    Abdul Kadir A, Noor NM, Mukhtar AF
    Hum Vaccin Immunother, 2021 Oct 29.
    PMID: 34714713 DOI: 10.1080/21645515.2021.1989915
    Health care workers play an important role in supporting childhood vaccination as they are the most trusted source of vaccine-related information for parents. However, there is limited validated tools to measure their knowledge and attitude on childhood vaccination. This study aims to develop and validate knowledge and attitude regarding childhood vaccination (KACV) questionnaire among healthcare workers. The questionnaire was developed based on literature reviews and underwent a sequential validation process, including content, face validity and exploratory factor analysis. However, the attitude section is unidimensional and has undergone reliability analysis only. The preliminary knowledge questionnaire contains 33 items and the attitude questionnaire consists of 17 items. The preliminary KACV showed a high item Content Validity Index and Face Validity Index. The final questionnaire consists of 10 items for knowledge and 15 items for attitude. The Cronbach alpha for the knowledge and attitude section were 0.896 and 0.861, respectively. KACV is a valid and reliable tool to measure healthcare workers' knowledge and attitude on childhood vaccination.
  20. Fulltext Evaluating the effects of plasticizer interactions with HPMC on the tack-behavior of polymer film-forming coating solutions
    Saringat HB, Sheikh KA, Khan GM
    Pak J Pharm Sci, 2004 Jul;17(2):29-39.
    PMID: 16414595
    Tack is a concept that is widely used to describe the forces or energies involved in the separation of two parallel surfaces initially in contact through an intervening thin liquid film. The tackiness may cause tablets to stick with each other or to the walls of the coating apparatus. In this study, the HPMC coating solutions were evaluated for their tackiness and the effects of interactions between the polymer and plasticizers on the tack behavior of HPMC film-forming coating solutions were investigated, using type TA-XT2 texture analyzer. It was found that experimental factors such as the contact time, rate of separation and volume of the film-forming test solution could effectively influence the magnitude of tack behavior. Moreover, up to certain levels, the addition of plasticizers such as PEG 400 & 1000 and of triacetin caused a reduction in the tack value of the polymer solutions. It was concluded that in general, the tackiness depended upon the molecular weight and/or type and concentration of a plasticizer. The efficiency of plasticizers used to reduce the tackiness of HPMC solutions ranked as PEG1000 > triacetin > PEG400.
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