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Fulltext Congenital dislocation of hip in children: a review of patients treated in the Institute of Orthopaedics and Traumatology, General Hospital, Kuala Lumpur, 1975-1988

Chai AL, Sivanantham M

Med J Malaysia, 1990 Jun;45(2):159-68.
PMID: 2152021

A retrospective review of patients with congenital dislocation of the hip (CDH) seen in the Institute of Orthopaedics, Kuala Lumpur General Hospital from 1975 to 1988 is presented. There was a female predominance of 17 to five. The average follow-up was 43 months and the average age at final assessment was 63 months. The results were assessed clinically and radiographically using Severin criteria. Eighty eight percent of the hips had excellent or good clinical results at final review compared with 40% of the hips which had excellent or good radiological grading (Severin I and II). Initial acetabular angle before treatment and types of treatment appeared to have a correlation with the final result. The incidence of avascular necrosis was 16%.
Haldane-Andrews substrate inhibition kinetics for pilot scale thermophilic anaerobic degradation of sugarcane vinasse

Chai A, Wong YS, Ong SA, Aminah Lutpi N, Sam ST, Kee WC, et al.

Bioresour Technol, 2021 Sep;336:125319.
PMID: 34049168 DOI: 10.1016/j.biortech.2021.125319

A pilot scale anaerobic degradation of sugarcane vinasse was carried out at various hydraulic retention time (HRT) in the Anaerobic Suspended Growth Closed Bioreactor (ASGCB) under thermophilic temperature. The performance and kinetics were evaluated through the Haldane-Andrews model to investigate the substrate inhibition potential of sugarcane vinasse. All parameters show great performance between HRT 35 and 25 days: chemical oxygen demand (COD) reduction efficiency (81.6 to 86.8%), volatile fatty acids (VFA) reduction efficiency (92.4 to 98.5%), maximum methane yield (70%) and maximum biogas production (19.35 L/day). Furthermore, steady state values from various HRT were obtained in the kinetic evaluation for: rXmax (1.20 /day), Ks (19.95 gCOD/L), Ki (7.00 gCOD/L) and [Formula: see text] (0.33 LCH4/gCOD reduction). This study shows that anaerobic degradation of sugarcane vinasse through ASGCB could perform well at high HRT and provides a low degree of substrate inhibition as compared to existing studies from literature.
Fulltext Photocatalytic Degradation of Sugarcane Vinasse Using ZnO Photocatalyst: Operating Parameters, Kinetic Studies, Phytotoxicity Assessments, and Reusability

Kee WC, Wong YS, Ong SA, Lutpi NA, Sam ST, Chai A, et al.

Int J Environ Res, 2022;16(1):3.
PMID: 34899925 DOI: 10.1007/s41742-021-00382-6

Abstract: Photocatalytic degradation performance is highly related to optimized operating parameters such as initial concentration, pH value, and catalyst dosage. In this study, the impact of various parameters on the photocatalytic degradation of anaerobically digested vinasse (AnVE) has been determined through decolourization and chemical oxygen demand (COD) reduction efficiency using zinc oxide (ZnO) photocatalyst. In this context, the application of photocatalytic degradation in treating sugarcane vinasse using ZnO is yet to be explored. The COD reduction efficiency and decolourization achieved 83.40% and 99.29%, respectively, under the conditions of 250 mg/L initial COD concentration, pH 10, and 2.0 g/L catalyst dosage. The phytotoxicity assessment was also conducted to determine the toxicity of AnVE before and after treatment using mung bean (Vigna radiata). The reduction of root length and the weight of mung bean indicated that the sugarcane vinasse contains enormous amounts of organic substances that affect the plant's growth. The toxicity reduction in the AnVE solution can be proved by UV-Vis absorption spectra. Furthermore, the catalyst recovery achieved 93% in the reusability test. However, the COD reduction efficiency and decolourization were reduced every cycle. It was due to the depletion of the active sites in the catalyst with the adsorption of organic molecules. Thus, it can be concluded that the photocatalytic degradation in the treatment of AnVE was effective in organic degradation, decolorization, toxicity reduction and can be reused after the recovery process.
Graphical abstract:
Chemical and biological combined treatment for sugarcane vinasse: selection of parameters and performance studies

Kee WC, Wong YS, Ong SA, Lutpi NA, Sam ST, Dahalan FA, et al.

Environ Sci Pollut Res Int, 2023 May;30(24):65364-65378.
PMID: 37081370 DOI: 10.1007/s11356-023-27046-6

Sugarcane vinasse has been reported as a high strength industrial wastewater that could cause severe environmental pollution due to its complex and bio-refractory compounds. Thus, the combined coagulation and sequencing batch biofilm reactor (SBBR) system was employed for the sugarcane vinasse treatment. This study aims to determine the recommended conditions of various parameters under coagulation and SBBR and investigate the effectiveness of combined processes. First, the approach of the coagulation process could achieve the maximum COD reduction and decolorization efficiencies of 79.0 ± 3.4% and 94.1 ± 1.9%, respectively, under the recommended conditions. Next, SBBR as an integrated biofilm reactor showed excellent synergistic biodegradability, removing 86.6 ± 4.3% COD concentration and 94.6 ± 3.8% color concentration at 3.0 g·COD/L of substrate loading concentration. The kinetic studies of SBBR revealed that the first-order kinetic model was the best fit for COD reduction efficiency. In contrast, the second-order kinetic model was the best fit for decolorization efficiency. The SBBR reaction was further investigated by ultraviolet-visible spectrophotometry (UV-Vis). In the combined processes, SBBR followed by the coagulation process (SBBR-CP) showed greater COD reduction and decolorization efficiencies (97.5 ± 0.3 and 99.4 ± 0.1%) when compared to the coagulation process followed by SBBR (CP-SBBR). This study demonstrated the removal performance and potential application of the combined sequential process to produce effluent that can be reused for bioethanol production and fertigation. This finding provides additional insight for developing effective vinasse treatment using combined chemical and biological processes.
Exploring the potential of thermophilic anaerobic co-digestion between agro-industrial waste and water hyacinth: operational performance, kinetic study and degradation pathway

Chai A, Wong YS, Ong SA, Lutpi NA, Sam ST, Wirach T, et al.

Bioprocess Biosyst Eng, 2023 Jul;46(7):995-1009.
PMID: 37160769 DOI: 10.1007/s00449-023-02879-0

Anaerobic co-digestion (co-AD) of agro-industrial waste, namely, palm oil mill effluent (POME) and sugarcane vinasse (Vn), with water hyacinth (WH) as co-substrate was carried out in two separate Anaerobic Suspended Growth Closed Bioreactors (ASGCBs) under thermophilic (55 °C) conditions. The highest chemical oxygen demand (COD) and soluble COD reduction in co-AD of POME-WH (78.61%, 78.86%) is slightly higher than co-AD of Vn-WH (75.75%, 78.24%). However, VFA reduction in co-AD of POME-WH (96.41%) is higher compared to co-AD of Vn-WH (85.94%). Subsequently, biogas production peaked at 13438 mL/day values and 16122 mL/day for co-AD of POME-WH and Vn-WH, respectively. However, the methane content was higher in the co-AD of POME-WH (72.04%) than in the co-AD of Vn-WH (69.86%). Growth yield (YG), maximum specific substrate utilization rate (rx,max) and maximum specific biomass growth rate (μmax) are higher in co-AD of POME-WH, as supported by the higher mixed liquor volatile suspended solids (MLVSS) and COD reduction efficiency compared to co-AD of Vn-WH. However, methane yield ([Formula: see text]) reported in the co-AD of POME-WH and Vn-WH are 0.2748 and 0.3112 L CH4/g CODreduction, respectively, which suggests that WH is a more suitable co-substrate for Vn compared to POME.
Fulltext Optimising technology to measure functional vision, mobility and service outcomes for people with low vision or blindness: protocol for a prospective cohort study in Australia and Malaysia

Deverell L, Meyer D, Lau BT, Al Mahmud A, Sukunesan S, Bhowmik J, et al.

BMJ Open, 2017 12 21;7(12):e018140.
PMID: 29273657 DOI: 10.1136/bmjopen-2017-018140

INTRODUCTION: Orientation and mobility (O&M) specialists assess the functional vision and O&M skills of people with mobility problems, usually relating to low vision or blindness. There are numerous O&M assessment checklists but no measures that reduce qualitative assessment data to a single comparable score suitable for assessing any O&M client, of any age or ability, in any location. Functional measures are needed internationally to align O&M assessment practices, guide referrals, profile O&M clients, plan appropriate services and evaluate outcomes from O&M programmes (eg, long cane training), assistive technology (eg, hazard sensors) and medical interventions (eg, retinal implants). This study aims to validate two new measures of functional performance vision-related outcomes in orientation and mobility (VROOM) and orientation and mobility outcomes (OMO) in the context of ordinary O&M assessments in Australia, with cultural comparisons in Malaysia, also developing phone apps and online training to streamline professional assessment practices.
METHODS AND ANALYSIS: This multiphase observational study will employ embedded mixed methods with a qualitative/quantitative priority: corating functional vision and O&M during social inquiry. Australian O&M agencies (n=15) provide the sampling frame. O&M specialists will use quota sampling to generate cross-sectional assessment data (n=400) before investigating selected cohorts in outcome studies. Cultural relevance of the VROOM and OMO tools will be investigated in Malaysia, where the tools will inform the design of assistive devices and evaluate prototypes. Exploratory and confirmatory factor analysis, Rasch modelling, cluster analysis and analysis of variance will be undertaken along with descriptive analysis of measurement data. Qualitative findings will be used to interpret VROOM and OMO scores, filter statistically significant results, warrant their generalisability and identify additional relevant constructs that could also be measured.
ETHICS AND DISSEMINATION: Ethical approval has been granted by the Human Research Ethics Committee at Swinburne University (SHR Project 2016/316). Dissemination of results will be via agency reports, journal articles and conference presentations.