Displaying publications 41 - 60 of 71 in total

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  1. Ahmed M. Mbarib, Mohammad Hamiruce Marhaban, Abdul Rahman Ramli
    MyJurnal
    Skin colour is an important visual cue for face detection, face recogmtlon, hand segmentation for gesture analysis and filtering of objectionable images. In this paper, the adaptive skin color detection model is proposed, based on two bivariate normal distribution models of the skin chromatic subspace, and on image segmentation using an automatic and adaptive multi-thresholding technique. Experimental results on images presenting a wide range of variations in lighting condition and background demonstrate the efficiency of the proposed skin-segmentation algorithm.
    Matched MeSH terms: Lighting
  2. Mohd Fudzi L, Zainal Z, Lim HN, Chang SK, Holi AM, Sarif Mohd Ali M
    Materials (Basel), 2018 Apr 29;11(5).
    PMID: 29710822 DOI: 10.3390/ma11050704
    Despite its large band gap, ZnO has wide applicability in many fields ranging from gas sensors to solar cells. ZnO was chosen over other materials because of its large exciton binding energy (60 meV) and its stability to high-energy radiation. In this study, ZnO nanorods were deposited on ITO glass via a simple dip coating followed by a hydrothermal growth. The morphological, structural and compositional characteristics of the prepared films were analyzed using X-ray diffractometry (XRD), field emission scanning electron microscopy (FESEM), and ultraviolet-visible spectroscopy (UV-Vis). Photoelectrochemical conversion efficiencies were evaluated via photocurrent measurements under calibrated halogen lamp illumination. Thin film prepared at 120 °C for 4 h of hydrothermal treatment possessed a hexagonal wurtzite structure with the crystallite size of 19.2 nm. The average diameter of the ZnO nanorods was 37.7 nm and the thickness was found to be 2680.2 nm. According to FESEM images, as the hydrothermal growth temperature increases, the nanorod diameter become smaller. Moreover, the thickness of the nanorods increase with the growth time. Therefore, the sample prepared at 120 °C for 4 h displayed an impressive photoresponse by achieving high current density of 0.1944 mA/cm².
    Matched MeSH terms: Lighting
  3. Hassan MA, Malik AS, Fofi D, Karasfi B, Meriaudeau F
    PMID: 32287815 DOI: 10.1016/j.measurement.2019.07.032
    The paper presents a feasibility study for heart rate measurement using a digital camera to perform health monitoring. The feasibility study investigates the reliability of the state of the art heart rate measuring methods in realistic situations. Therefore, an experiment was designed and carried out on 45 subjects to investigate the effects caused by illumination, motion, skin tone, and distance variance. The experiment was conducted for two main scenarios; human-computer interaction scenario and health monitoring scenario. The human-computer scenario investigated the effects caused by illumination variance, motion variance, and skin tone variance. The health monitoring scenario investigates the feasibility of health monitoring at public spaces (i.e. airports, subways, malls). Five state of the art heart rate measuring methods were re-implemented and tested with the feasibility study database. The results were compared with ground truth to estimate the heart rate measurement error. The heart rate measurement error was analyzed using mean error, standard deviation; root means square error and Pearson correlation coefficient. The findings of this experiment inferred promising results for health monitoring of subjects standing at a distance of 500 cm.
    Matched MeSH terms: Lighting
  4. Sirimahachai R, Harome H, Wongnawa S
    Sains Malaysiana, 2017;46:1393-1399.
    AgCl/BiYO3
    composite was successfully synthesized via the aqueous precipitation method followed by calcination. The
    varied amount of AgCl (10, 20 and 30%) was mixed into BiYO3
    via sonochemical-assisted method. The structures and
    morphologies of the as-prepared AgCl/BiYO3
    composite were characterized by x-ray diffraction (XRD), scanning electron
    microscopy (SEM) and UV-vis diffused reflectance spectroscopy (UV-vis DRS). The optical absorption spectrum of AgCl/
    BiYO3
    composite showed strong absorption in visible region. The photocatalytic activity of AgCl/BiYO3
    composite was
    evaluated by the photodegradation of reactive orange16 (RO16), which was selected to represent the dye pollutants,
    under UV and visible light irradiation. The results indicated that 20% AgCl/BiYO3 photocatalyst was the most capable
    photocatalyst in this series in the degradation of RO16 under both UV and visible light illumination within 1 h. Moreover,
    the mechanism of photocatalytic degradation of AgCl/BiYO3
    was elucidated using three types of free radical scavengers.
    The significant enhancement was attributed to the formation of AgCl/BiYO3
    heterojunction resulting in the low electronhole
    pair recombination rate.
    Matched MeSH terms: Lighting
  5. Prepageran N, Lingham OR
    PMID: 23120731 DOI: 10.1007/s12070-010-0090-9
    The advent of endoscopes has revolutionized rhinology and the traditional headlight based surgeries have largely been replaced by endoscopes. Septoplasty for deviated nasal septum or Sluder's neuralgia have been conventionally performed with the aid of headlight. This can be technically challenging as visualization of the nasal cavity, particularly the posterior portion is rather limited as the procedure is performed via the nostrils. In addition, with headlights for illumination, teaching this procedure can be difficult as only the surgeon who is wearing the headlights has direct vision of the surgical field.Endoscopic septoplasty is an accepted alternative to traditional headlight approach to septoplasty. This approach provides a direct-targeted route to the anatomic deformity, improved visualization, and magnification of the surgical field. Our experience in endoscopic septoplasty is highlighted in this paper, excluding septoplasties performed as part of exposure to the sinuses. We use the open book method that to best of our knowledge has not been described in literature before.
    Matched MeSH terms: Lighting
  6. Ch'ng YH, Osman MA, Jong HY
    Malays J Med Sci, 2021 Apr;28(2):161-170.
    PMID: 33958970 DOI: 10.21315/mjms2021.28.2.15
    Background: Specific language impairment (SLI) diagnosis is inconvenient due to manual procedures and hardware cost. Computer-aided SLI diagnosis has been proposed to counter these inconveniences. This study focuses on evaluating the feasibility of computer systems used to diagnose SLI.

    Methods: The accuracy of Webgazer.js for software-based gaze tracking is tested under different lighting conditions. Predefined time delays of a prototype diagnosis task automation script are contrasted against with manual delays based on human time estimation to understand how automation influences diagnosis accuracy. SLI diagnosis binary classifier was built and tested based on randomised parameters. The obtained results were cross-compared to Singlims_ES.exe for equality.

    Results: Webgazer.js achieved an average accuracy of 88.755% under global lighting conditions, 61.379% under low lighting conditions and 52.7% under face-focused lighting conditions. The diagnosis task automation script found to execute with actual time delays with a deviation percentage no more than 0.04%, while manually executing time delays based on human time estimation resulted in a deviation percentage of not more than 3.37%. One-tailed test probability value produced by both the newly built classifier and Singlims_ES were observed to be similar up to three decimal places.

    Conclusion: The results obtained should serve as a foundation for further evaluation of computer tools to help speech language pathologists diagnose SLI.

    Matched MeSH terms: Lighting
  7. Chen AH, Norazman FN, Buari NH
    Indian J Ophthalmol, 2012 Mar-Apr;60(2):101-4.
    PMID: 22446903 DOI: 10.4103/0301-4738.90489
    BACKGROUND: Visual acuity is an essential estimate to assess ability of the visual system and is used as an indicator of ocular health status.
    AIM: The aim of this study is to investigate the consistency of acuity estimates from three different clinical visual acuity charts under two levels of ambient room illumination.
    MATERIALS AND METHODS: This study involved thirty Malay university students aged between 19 and 23 years old (7 males, 23 females), with their spherical refractive error ranging between plano and -7.75D, astigmatism ranging from plano to -1.75D, anisometropia less than 1.00D and with no history of ocular injury or pathology. Right eye visual acuity (recorded in logMAR unit) was measured with Snellen letter chart (Snellen), wall mounted letter chart (WM) and projected letter chart (PC) under two ambient room illuminations, room light on and room light off.
    RESULTS: Visual acuity estimates showed no statistically significant difference when measured with the room light on and with the room light off (F1,372 = 0.26, P = 0.61). Post-hoc analysis with Tukey showed that visual acuity estimates were significantly different between the Snellen and PC (P = 0.009) and between Snellen and WM (P = 0.002).
    CONCLUSIONS: Different levels of ambient room illumination had no significant effect on visual acuity estimates. However, the discrepancies in estimates of visual acuity noted in this study were purely due to the type of letter chart used.
    Matched MeSH terms: Lighting*
  8. Teh KK, Ng ES, Choon DS
    J Hand Surg Eur Vol, 2009 Aug;34(4):506-10.
    PMID: 19675032 DOI: 10.1177/1753193409100962
    This cadaveric study evaluates the margin of safety and technical efficacy of mini open carpal tunnel release performed using Knifelight (Stryker Instruments) through a transverse 1 cm wrist incision. A single investigator released 32 wrists in 17 cadavers. The wrists were then explored to assess the completeness of release and damage to vital structures including the superficial palmar arch, palmar cutaneous branch and recurrent branch of the median nerve. All the releases were complete and no injury to the median nerve and other structures were observed. The mean distance of the recurrent motor branch to the ligamentous divisions was 5.7 +/- 2.4 mm, superficial palmar arch was 8.7 +/- 3.1 mm and palmar cutaneous branch to the ligamentous division was 7.2 +/- 2.4 mm. The mean length of the transverse carpal ligament was 29.3 +/- 3.7 mm. Guyon's canal was preserved in all cases.
    Matched MeSH terms: Lighting/instrumentation*
  9. Srinivasan V, Spence DW, Pandi-Perumal SR, Trakht I, Esquifino AI, Cardinali DP, et al.
    Breast Cancer Res Treat, 2008 Apr;108(3):339-50.
    PMID: 17541739
    Although many factors have been suggested as causes for breast cancer, the increased incidence of the disease seen in women working in night shifts led to the hypothesis that the suppression of melatonin by light or melatonin deficiency plays a major role in cancer development. Studies on the 7,12-dimethylbenz[a]anthracene and N-methyl-N-nitrosourea experimental models of human breast cancer indicate that melatonin is effective in reducing cancer development. In vitro studies in MCF-7 human breast cancer cell line have shown that melatonin exerts its anticarcinogenic actions through a variety of mechanisms, and that it is most effective in estrogen receptor (ER) alpha-positive breast cancer cells. Melatonin suppresses ER gene, modulates several estrogen dependent regulatory proteins and pro-oncogenes, inhibits cell proliferation, and impairs the metastatic capacity of MCF-7 human breast cancer cells. The anticarcinogenic action on MCF-7 cells has been demonstrated at the physiological concentrations of melatonin attained at night, suggesting thereby that melatonin acts like an endogenous antiestrogen. Melatonin also decreases the formation of estrogens from androgens via aromatase inhibition. Circulating melatonin levels are abnormally low in ER-positive breast cancer patients thereby supporting the melatonin hypothesis for breast cancer in shift working women. It has been postulated that enhanced endogenous melatonin secretion is responsible for the beneficial effects of meditation as a form of psychosocial intervention that helps breast cancer patients.
    Matched MeSH terms: Lighting/adverse effects*
  10. Van Rostenberghe H, Ho JJ, Lim CH, Abd Hamid IJ
    Cochrane Database Syst Rev, 2020 07 01;7:CD012011.
    PMID: 32609375 DOI: 10.1002/14651858.CD012011.pub2
    BACKGROUND: Phototherapy is a well-established effective therapy for treating babies with significant neonatal jaundice. Studies have shown that increasing light intensity will increase its efficiency. A potentially inexpensive and easy way of increasing the intensity of light on the body of the infant may be to hang reflective materials from the sides of phototherapy units.

    OBJECTIVES: To assess the effects of reflective materials in combination with phototherapy compared with phototherapy alone for unconjugated hyperbilirubinaemia in neonates.

    SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 11), in the Cochrane Library; Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations, Daily and Versions(R); and the Cumulative Index of Nursing and Allied Health Literature (CINAHL), on 1 November 2019. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

    SELECTION CRITERIA: We included randomised and quasi-randomised controlled trials if the participants, who were term or preterm infants, received phototherapy with curtains made of reflective materials of any type in the treatment arm, and if those in the comparison arm received similar phototherapy without curtains or other intensified phototherapy, such as a double bank of lights.

    DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. We used the GRADE approach to assess the certainty of evidence.

    MAIN RESULTS: Of 15 studies identified, we included 12 (1288 babies) in the review - 11 comparing phototherapy with reflective materials and phototherapy alone, and one comparing a single phototherapy light bank with reflective materials with double phototherapy. All reflective materials consisted of curtains on three or four sides of the cot and were made of white plastic (five studies), white linen (two studies), or aluminium (three studies); materials were not specified in two studies. Only 11 studies (10 comparing reflective materials versus none and one comparing reflective curtains and a single bank of lights with a double (above and below) phototherapy unit) provided sufficient data to be included in the meta-analysis. Two excluded studies used the reflective materials in a way that did not meet our inclusion criteria, and we excluded one study because it compared four different phototherapy interventions not including reflective materials. The risk of bias of included studies was generally low, but all studies had high risk of performance bias due to lack of blinding of the intervention. Three studies (281 participants) reported a decline in serum bilirubin (SB) (μmol/L) at four to eight hours (mean difference (MD) -14.61, 95% confidence interval (CI) -19.80 to -9.42; I² = 57%; moderate-certainty evidence). Nine studies (893 participants) reported a decline in SB over 24 hours and showed a faster decline in SB in the intervention group, but heterogeneity (I² = 97%) was too substantial to permit a meaningful estimate of the actual effect size (very low-certainty evidence). Subgroup analysis by type of reflective material used did not explain the heterogeneity. Exchange transfusion was reported by two studies; both reported none in either group. Four studies (466 participants) reported the mean duration of phototherapy, and in each of these studies, it was reduced in the intervention group but there was substantial heterogeneity (I² = 88%), precluding meaningful meta-analysis of data. The only two studies that reported the mean duration of hospital stay in hours showed a meaningful reduction (MD -41.08, 95% CI -45.92 to -36.25; I² = 0; moderate-certainty evidence). No studies reported costs of the intervention, parental or medical staff satisfaction, breastfeeding outcomes, or neurodevelopmental follow-up. The only study that compared use of curtains with double phototherapy reported similar results for both groups. Studies that monitored adverse events did not report increased adverse events related to the use of curtains, including acute life-threatening events, but other rarer side effects could not be excluded.

    AUTHORS' CONCLUSIONS: Moderate-certainty evidence shows that the use of reflective curtains during phototherapy may result in greater decline in SB. Very low-certainty evidence suggests that the duration of phototherapy is reduced, and moderate-certainty evidence shows that the duration of hospital stay is also reduced. Available evidence does not show any increase in adverse events, but further studies are needed.

    Matched MeSH terms: Lighting/instrumentation
  11. Chen AH, Ahmad A, Kearney S, Strang N
    Graefes Arch Clin Exp Ophthalmol, 2019 Sep;257(9):1997-2004.
    PMID: 31273509 DOI: 10.1007/s00417-019-04405-z
    PURPOSE: Near work, accommodative inaccuracy and ambient lighting conditions have all been implicated in the development of myopia. However, differences in accommodative responses with age and refractive error under different visual conditions remain unclear. This study explores differences in accommodative ability and refractive error with exposure to differing ambient illumination and visual demands in Malay schoolchildren and adults.

    METHODS: Sixty young adults (21-25 years) and 60 schoolchildren (8-12 years) were recruited. Accommodative lag and accommodative fluctuations at far (6 m) and near (25 cm) were measured using the Grand Seiko WAM-5500 open-field autorefractor. The effects of mesopic room illumination on accommodation were also investigated.

    RESULTS: Repeated-measures ANOVA indicated that accommodative lag at far and near differed significantly between schoolchildren and young adults [F(1.219, 35.354) = 11.857, p  0.05). Accommodative lag and fluctuations were greater under mesopic room conditions for all ages [all p 

    Matched MeSH terms: Lighting*
  12. Lee YM, Sheppard E
    Accid Anal Prev, 2016 Oct;95(Pt A):202-8.
    PMID: 27450792 DOI: 10.1016/j.aap.2016.07.011
    Failure in making the correct judgment about the intention of an approaching vehicle at a junction could lead to a collision. This paper investigated the impact of dynamic information on drivers' judgments about the intentions of approaching cars and motorcycles, and whether a valid or invalid signal was provided was also manipulated. Participants were presented with videoclips of vehicles approaching a junction which terminated immediately before the vehicle made any manoeuvre, or images of the final frame of each video. They were asked to judge whether or not the vehicle would turn. Drivers were better in judging the manoeuvre of approaching vehicles in dynamic than static stimuli, for both vehicle types. Drivers were better in judging the manoeuvre of cars than motorcycles for videos, but not for photographs. Drivers were also better in judging the manoeuvre of approaching vehicles when a valid signal was provided than an invalid signal, demonstrating the importance of providing a valid signal while driving. However, drivers were still somewhat successful in their judgments in most of the conditions with an invalid signal, suggesting that drivers were able to focus on other cues to intention. Finally, given that dynamic stimuli more closely reflect the demands of real-life driving there may be a need for drivers to adopt a more cautious approach while inferring a motorcyclist's intentions.
    Matched MeSH terms: Lighting/instrumentation*
  13. Sithravel R, Ibrahim R, Lye MS, Perimal EK, Ibrahim N, Dahlan ND
    PLoS One, 2018;13(11):e0207488.
    PMID: 30496193 DOI: 10.1371/journal.pone.0207488
    Workplace architectural lighting conditions that are biologically dim during the day are causing healthy individuals to experience light-induced health and performance-related problems. Dynamic lighting was reported beneficial in supporting individuals' psychological behavior and physiological responses during work period in Europe. It has yet to be investigated in workplaces with minimal/no natural daylight contribution in tropical Malaysia. Hence, an exploratory experimental study was initiated in an experimental windowless open-plan workplace in Universiti Putra Malaysia, Serdang. The aim was to identify dynamic lighting configurations that were more supportive of a morning boosting effect than the control constant lighting, to support dayshift individuals' psychophysiological wellbeing indicators during the peak morning work period. The immediate impact of a 2-hour morning exposure to overhead white LED (6500 K) with different horizontal illuminance levels and oscillations (lighting patterns) were investigated on physiological indicator limited to urinary 6-sulfatoxymelatonin, and psychological indicators for alertness, mood, visual comfort, cognitive and visual task performance. Not all of the investigated dynamic lighting configurations were supportive of a morning boost. Only configurations 500increased to750 and 500increased to1000 lx therapeutically supported most of the indicators. Both these configurations suppressed urinary 6-sulfatoxymelatonin, and improved alertness, cognitive performance, positive affect, and visual comfort better than 'visit 1: 500constant500' lx (control). The increasing oscillation was observed more beneficial for the morning boost in tropical Malaysia, which is in reverse to that specified in the human rhythmic dynamic lighting protocol developed by researchers from the Netherlands for application during winter. The findings from this study present the feasibility of dynamic architectural lighting acting as an environmental therapeutic solution in supporting the individuals' psychophysiological wellbeing indicators in windowless open-plan workplace in tropical Malaysia. Further investigations on the two prospective configurations are recommended to determine the better supportive one for the morning boosting effect in Malaysia.
    Matched MeSH terms: Lighting*
  14. Roslizar A, Alghoul MA, Bakhtyar B, Asim N, Sopian K
    ScientificWorldJournal, 2014;2014:310539.
    PMID: 25485294 DOI: 10.1155/2014/310539
    Buildings are among the largest consumers of energy. Part of the energy is wasted due to the habits of users and equipment conditions. A solution to this problem is efficient energy usage. To this end, an energy audit can be conducted to assess the energy efficiency. This study aims to analyze the energy usage of a primary school and identify the potential energy reductions and cost savings. A preliminary audit was conducted, and several energy conservation measures were proposed. The energy conservation measures, with reference to the MS1525:2007 standard, were modelled to identify the potential energy reduction and cost savings. It was found that the school's usage of electricity exceeded its need, incurring an excess expenditure of RM 2947.42. From the lighting system alone, it was found that there is a potential energy reduction of 5489.06 kWh, which gives a cost saving of RM 2282.52 via the improvement of lighting system design and its operating hours. Overall, it was found that there is a potential energy reduction and cost saving of 20.7% when the energy conservation measures are earnestly implemented. The previous energy intensity of the school was found to be 50.6 kWh/m(2)/year, but can theoretically be reduced to 40.19 kWh/mm(2)/year.
    Matched MeSH terms: Lighting
  15. Chen LH, Shen HT, Chang WH, Khalil I, Liao SY, A Yehye W, et al.
    Nanomaterials (Basel), 2020 Oct 07;10(10).
    PMID: 33036455 DOI: 10.3390/nano10101985
    Graphene (Gr)/gold (Au) and graphene-oxide (GO)/Au nanocomposites (NCPs) were synthesized by performing pulsed-laser-induced photolysis (PLIP) on hydrogen peroxide and chloroauric acid (HAuCl4) that coexisted with Gr or GO in an aqueous solution. A 3-month-long aqueous solution stability was observed in the NCPs synthesized without using surfactants and additional processing. The synthesized NCPs were characterized using absorption spectroscopy, transmission electron microscopy, Raman spectroscopy, energy dispersive spectroscopy, and X-ray diffraction to prove the existence of hybrid Gr/Au or GO/Au NCPs. The synthesized NCPs were further evaluated using the photocatalytic reaction of methylene blue (MB), a synthetic dye, under UV radiation, visible light (central wavelength of 470 nm), and full spectrum of solar light. Both Gr/Au and GO/Au NCPs exhibited photocatalytic degradation of MB under solar light illumination with removal efficiencies of 92.1% and 94.5%, respectively.
    Matched MeSH terms: Lighting
  16. Ting SL, Saimon R, Rahman MM, Safii R, Ho SL, John N, et al.
    Med J Malaysia, 2020 11;75(6):649-654.
    PMID: 33219172
    BACKGROUND AND OBJECTIVE: Physical and behavioural problems from extended usage of electronic devices are issues among primary school children. This study is aimed to investigate the prevalence of physical and behavioural complaints arising from the electronic device usage and to identify the potential factors that predicted the complaints.

    METHODS: This was a primary school-based cross-sectional study using multistage cluster sampling, conducted at Bau district in Sarawak, Malaysia in 40 primary schools. A questionnaire was used to collect information of usage pattern in insufficient lighting, timing and position. The physical and behavioural complaints were traced. Data analysis was performed using SPSS version 22. A p-value < 0.05 with 95% CI was considered as statistically significant.

    RESULTS: About 52.8% of the 569 students used digital devices in a bright room, 69.8% in the day time and 54.4% in sitting position. The physical complaints were headache (32.9%), neck, shoulder and back pain (32.9%) followed by by eye strain (31.8%). Regarding behavioural problems, 25.7% of the students had loss of interest in study and outdoor activities (20.7%), skipped meals (19.0%) and arguments/disagreements with parents (17.9%). After logistic regression analysis, the lying position (OR=1.71, 95% CI: 1.096, 2.688) and darkroom lighting (OR=2.323 95% CI: 1.138, 4.744) appeared to be potential predictors of the complaint.

    CONCLUSION: One-quarter of the students studied experienced physical complaints, and one-fifth had behavioural problems associated with the use of electronic devices. Lying position and darkroom lighting are the potential predictors of complaints. Therefore, we suggest that the children should use electronic devices in the sitting position with adequate room lighting.

    Matched MeSH terms: Lighting
  17. Keith LM, Matsumoto TK
    Plant Dis, 2013 Jan;97(1):146.
    PMID: 30722309 DOI: 10.1094/PDIS-07-12-0702-PDN
    Mangosteen (Garcinia mangostana L.) is a tropical evergreen tree that produces one of the most prized tropical fruits, commonly known as the "Queen of the Fruits.″ Mangosteen has the potential to occupy a rapidly expanding niche market in Hawaii. In October 2009, a disease was observed that produced brown leaf spots and blotches surrounded by bright yellow halos at a mangosteen orchard located in Hakalau, Hawaii (19° 53' 49″ N, 155° 7' 35″ W). Recently transplanted 10+ year old trees were 95 to 100% infected. Pieces of infected leaves and stems were surface-sterilized, plated on potato dextrose agar (PDA), and incubated at 24°C ± 1°C for 21 days. The fungus growing on PDA was pale buff with sparse aerial mycelium and acervuli containing black, slimy spore masses. Single spore isolates were used for the morphological characteristics and molecular analysis. Conidia were 5-celled. Apical and basal cells were hyaline; the three median cells were umber to olivaceous. Conidia (n = 50) were 24.3 ± 0.2 × 7.5 ± 0.1 μm, with apical appendages, typically three, averaging 24.3 ± 0.4 μm long, and a basal appendage averaging 6.7 ± 0.2 μm long. DNA sequences were obtained from the β-tubulin gene and the internal transcribed spacer (ITS1 and ITS2) and 5.8S regions of the rDNA to confirm the identification. The morphological descriptions and measurements were similar to P. virgatula (Kleb.) Steyaert (1). Although sequence data of the ITS region (GenBank Accession No. JN542546) supports the identity of the fungus as P. virgatula, the taxonomy of this genus remains confused since there are only a few type cultures, so it is impossible to use sequences in GenBank to reliably clarify species names (2). To confirm pathogenicity, six leaves of two 3-year-old seedlings were inoculated. Seven-day-old cultures grown on 10% V8 agar at 24°C under continuous fluorescent lighting were used for inoculations. The inoculum consisted of spore suspensions in sterile distilled water adjusted to 6 × 105 conidia/ml. Using a fine haired paint brush, the inoculum was brushed onto the youngest leaves, while sterile distilled water was used as the control. The plants were incubated in a clear plastic bag placed on the laboratory bench at 24°C for 48 hours, then placed on a greenhouse bench and observed weekly for symptoms. After 14 days, leaf spots ranging in size from pinpoint to 5.4 mm in diameter with a distinctive yellow halo were present. Within 35 days, the leaf spots enlarged to leaf blotches ranging in size from 11.5 × 13.3 mm up to 28.3 × 34.6 mm with brown centers and a distinctive yellow halo identical to the field symptoms. A Pestalotiopsis sp. identical to that used to inoculate the seedlings was recovered from the leaf spots and blotches, confirming Koch's postulates. The experiment was repeated twice. Pestalotiopsis leaf blight has been reported in other countries growing mangosteen, including Thailand, Malaysia, and North Queensland, Australia (3). However, to our knowledge, this is the first report of a Pestalotiopsis sp. causing a disease on mangosteen in Hawaii. Although this disease is considered a minor problem in the literature (3), effective management practices should be established to avoid potential production losses. References: (1) E. F. Guba. Monograph of Pestalotia and Monochaetia. Harvard University Press, Cambridge, MA. 1961. (2) S. S. N. Maharachchikumbura et al. Fungal Div. 50:167, 2011. (3) R. C. Ploetz. Diseases of Tropical Fruit Crops. CABI Publishing. Wallingford, Oxfordshire, UK, 2003.
    Matched MeSH terms: Lighting
  18. Anuar, I., Mohamad Jauhari, J., Mohd Riduan, A.
    MyJurnal
    Background: Level of comfort in working environment can contribute to increase level of health, emotion during working, level of safety, quality and productivity of work. A study of physical factors (heat, noise and lighting) is important to determine the level of comfort during working. This study was carried out to study those physical factors upon comfort level during working among Casting Shop workers in a car manufacturing factory.

    Methods: Instruments for the physical monitoring including Questemp°36 Thermal Environment Monitor, Sound Level Meter and Lux Meter were used at seven measured areas. The information about the level of comfort during working was collected using questionnaires among 65 respondents by random sampling method.

    Results: Measured data showed there were four measured areas which Wet Bulb Globe Temperature indoor (WBGTi) value are above the standard limit recommended by ACGIH, three measured areas recorded noise level above the standard limit recommended by Factories and Machineries (Noise Exposure) 1989, while there was no measured area recorded lighting reading below the standard limit recommended by MS ISO 8995:2005. Result from questionnaire found that the majority of the workers did not feel comfortable towards the heat and noise level in their workplace while most of the respondents felt comfortable towards lighting level in their workplace. Mean of WBGTi reading and lighting reading have a significant difference (p
    Matched MeSH terms: Lighting
  19. Mawlud SQ
    PMID: 30359852 DOI: 10.1016/j.saa.2018.10.032
    Enhanced red and orange fluorescence emissions of Sm3+ Rare earth (RE) ions were observed in sodium‑zinc tellurite glasses embedded with silver and gold nanoparticles (NPs). The fine distribution of NPs in the glass matrix with an average diameter ~ 11.09 nm and ~3.86 nm for Ag and Au NPs respectively were confirmed by using transmission electron microscope (TEM). The embedding of Ag and Au NPs into the glass structure caused an increasing in the transition emission intensity of Sm3+ ions, which is ascribed to the progress of the presence of the localized surface Plasmon resonance (LSPR) indicating from the characteristic absorption peaks. The luminescence and absorption spectra have been discussed using a standard hypothesis Judd-Ofelt theory for a certain absorption transitions 6P3/2, 4I11/2, 6F11/2, 6F9/2, 6F7/2, 6F5/2, 6F3/2, 6H15/2, 6F1/2 and emission transitions 6H5/2, H7/2, 6H9/2 and H11/2 under 409 nm excitation of the Sm3+ ions. The decay life time curve exhibited a non-exponential behavior of the studied glass samples and the results were compared with the similar reported glasses. An efficient red and orange fluorescence emission illustrate that the Sm3+-doped sodium‑zinc tellurite embedded with Ag and Au NPs are potential materials for the laser illumination.
    Matched MeSH terms: Lighting
  20. Nur Anira Syafiqah Hazman, Hassimi Abu Hasan, Kamrul Fakir Kamarudin, Nazlina Haiza Mohd Yasin, Mohd Sobri Takriff, Noor Irma Nazashida Mohd Hakimi
    Sains Malaysiana, 2018;47:1455-1464.
    Malaysian economy relies on palm oil industries as a driver for rural development. However, palm oil mill effluent
    (POME) that is generated from palm oil processing stages causes major environmental challenges. Before being
    released to the environment, POME treatment is crucial to comply with standard discharge limit. Microalgae have
    demonstrated excellent potential for phycoremediating POME and capturing CO2
    . In this study, local microalgae isolate
    such as Chlamydomonas sp. UKM 6 and Chlorella spp. UKM 8 were used for POME treatment in 21 days with different
    inoculum sizes (5%, 10% and 15%). In addition, an integrated treatment process was performed by taking the treated
    POME supernatant for cultivation of Chorella spp. UKM 2, Chorella sorokiniana UKM 3 and Chlorella vulgaris for CO2
    sequestration study. Different CO2
    concentrations (5%, 10% and 15%) were used and the experiments were carried
    out in 10 days under continuous illumination. The results showed that among two species involves in POME treatment,
    Chlamydomonas sp. UKM 6 showed a great potential to remove pollutant such as COD (56%), nitrogen (65%) and
    phosphorus (34%). The biomass after POME treatment and CO2
    biofixation content high lipid (90 mg lipid/g biomass)
    which can be the potential source for biodiesel production. In CO2
    sequestration study, C. sorokininana UKM3 able
    to takes up to 15% CO2
    with CO2
    uptake rate of 273 mgL-1d-1. In this study, the integrated system of POME treatment
    and CO2
    sequestration were feasible using microalgae.
    Matched MeSH terms: Lighting
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