Temporal distribution of water characteristics in the Miri estuary, east Malaysia

This baseline study was carried out to investigate the physicochemical factors such as pH, salinity, temperature, turbidity, total dissolved solids (TDS), total suspended solids and dissolved oxygen (DO), as well as nutrient (nitrate, phosphate, ammonium) concentrations and the level of heavy metals (Fe, Zn, Cu, Mn) in the surface water of the Miri estuary at four sampling times based on the four seasons of Malaysia. Results indicated marked temporal differences in each of the water characteristics measured (except ammonium), where DO level (mean: 3.6 mg/L) was found in a concern level. The principle component analysis (PCA) was applied to the hydrological and hydrochemical data set of the Miri estuary; results indicated that principle component 1 and principle component 2 explained 61.78 and 18.69%, respectively, of the total variance in the data set. Besides, results of PCA also indicated that the factors for water characteristics variations were mainly related to TDS, salinity, and Fe. The data presented here will serve as benchmark information, especially to the agencies related to the formulation of suitable policy on water quality in such areas

Reliability measurement of total aberrations using Galilei G4 Dual Scheimpflug Analyzer

38 eyes of subjects aged 21 to 27 years with spherical equivalent ranging from -1.50D to 7.00D were recruited. Corneal wavefront aberrations were measured; LoA (1st and 2nd order aberration), HoA (3rd and 4th order aberration). Any conditions in which corneal videoker-atography could not provide reproducible measurement (obstruction of the central cornea) were also excluded. Total corneal aberrations were measured based on root mean square (RMS) value converted from Zernike polynomials. For repeatability measurement, three repetitive measure-ments in five minutes for each eye in a single session were taken by 2 experience examiners. Time-interval between measurements was set at one week for reproducibility measurement,. Re-peated-measures analysis of variance (RM-ANOVA), Bland-Altman, limits of agreement and intraclass correlation coefficients (ICCs) were used for analysis

Phytoplankton Composition and Productivity of a Shallow Tropical Lake

Phy toplankton composition and production in Paya Bungor, Pahang, were studied from October 1981 to Septemoer 1982 and from January to December 1982 respectively. Phytoplankton diversity is in the order of Chlorophyta> Bacillariophyceae > Cyanophyta> Chrysophyceae > Euglenophyta > Phyrrhophyta; but the order in terms or ab~ndance is Cyanophyta> Chrysophyceae > Chlorophyceae> Bacillariophyceae. The brown water system of Paya Bungor seems to contain a higher phytoplankton production than the white water system. Maximum production generally occurs at the top layer of the water, but shifts to the subsurface layers on hot days due to photo-inhibition at the surface. Generally, nutrient and light energy are the two most important factors controlling phytoplankton production in Paya Bungor

In-vivo confocal microscopy: comparison of Keratocytes cell density (KCD) between Femtosecond LASIK (FS-LASIK) and Photorefractive keratectomy (PRK) at one month follow-up

Sixteen eyes of 8 participants who underwent FS-LASIK and PRK involved in this prospective nonrandomised study. Inclusion criteria includes of having moderate to high myopia (spherical equivalent, SE: - 3.25D to 9.25D).A flap was created and repositioned back after ablated in FS-LASIK, while in PRK the entire corneal epithelium was removed(flap-less)before ablated. Central corneas were scanned throughout their full thickness using HRTIII/RCM during baseline and post-operative 1 month by single examiner. Morphologic modifications of KCD were evaluated. Using image analysis, KCD was measured in cell/mm2. Two images with non-artefact were selected from each stromal layer for evaluation of KCD and the average mean was taken for analysis. KCD was manually calculated within a region of interest (ROI)set at 0.16mm2 by modification of brightness and contrast. Cells which are more illuminated and refringent were selected and analysed using Wilcoxon signed-rank and Mann-Whitney U test

Refractive surprise in post-cataract surgery in post Epi-LASIK patient : a lesson learnt

Post-myopic laser refractive surgery corneal power measurement for intraocular lens power calculation is one of the most challenging issues in cataract surgery. Standard keratometry measurement is likely to be overestimated which could lead to false-low intraocular lens power. As a result, this can lead to hyperopic surprise. Contact lens method is an alternative method which is relatively inexpensive and accessible procedure in many optometry and ophthalmology centres. The contact lens method with optimised equations have been used for this case to obtain an accurate postoperative corneal power

Comparison between point-based and ring-based technologies in keratometric measurement among post myopic laser refractive surgery patients

Introduction: Corneal power or keratometric value represents two-third of total refractive power of the eye. It is an important parameter in intraocular lens calculation. Purpose of the study was to evaluate repeatability and agreement of keratometric measurements obtained from a six points-based keratometry device; IOLMaster 500 (Carl Zeiss Meditec AG, Jena, Germany) and two Placido disc-based keratometry devices; Atlas Topographer 995 and 9000 models (Carl Zeiss Meditec AG, Jena, Germany). Materials and method: A total of 97 post myopic laser refractive surgery subjects were recruited. Three set of mean corneal power measurements from each device were performed by an examiner in a single visit. The repeatability was evaluated by withinsubject standard deviation, coefficient of variation and intraclass correlation coefficient. A one-way repeated measures analysis of variance was conducted to evaluate keratometric measurement differences between the devices. The BlandAltman analysis was employed to assess inter-device agreement. Results: There were no significant differences of three repeated keratometric measurements in each device (p > 0.05). IOLMaster showed the lowest coefficient of variations in all meridians (< 0.30%).The intraclass correlations were higher than 0.90 in all devices. For inter-device agreement, there were statistically significant differences between Atlas 9000-IOLMaster and Atlas 995-IOLMaster (p < 0.05). The 95% limit of agreement ranged from 0.94 to 1.68. Conclusion: The six points-based technology has a higher repeatability compared to ring based technology in measuring postoperative keratometric measurements. Different keratometry technologies cannot be used interchangeably in clinical setting

The Critical Review on the Malaysian Construction Industry

The construction industry is a very important part of Malaysian economy. The government’s aim is to make the industry more productive, efficient and safe. However reports and researchers on Malaysian construction industry showed little evidence of success on the efforts to improve productivity of the industry. This paper sought to provide an understanding on the characteristics of the Malaysian construction industry and further understand the issues/problems related to the industry. The paper is based on critical literature synthesis on the Malaysian construction industry. It is identified that the characteristics and current practices in the Malaysian construction industry has led to serious problem. Malaysian construction industry is identified as being fragmented, having high dependency on unskilled foreign labour, poor application of technology and problems on the implementation of policy. The issues identified by this literature synthesis will form a basis for future research on the Malaysian construction industry. Keywords: Construction industry, Malaysi