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SYNTHESIS OF BIFUNCTIONAL ACTIVATED CARBON FROM GASIFICATION RESIDUES FOR MALACHITE GREEN DYE AND ATENOLOL ADSORPTION
No full textThe abundance of gasification char residues which contributed to solid waste management problem is one of the major concerns in biomass gasification industry. This study aims to synthesize activated carbon (AC) derived from gasification residues for malachite green (MG) dye and atenolol (ATN) adsorption via microwave- induced potassium hydroxide (KOH) and carbon dioxide (CO2) activation. Optimum preparation conditions for all ACs prepared were determined using response surface methodology (RSM). Gasified Glyricidia sepium woodchips-based AC (GGSWAC) showed the highest BET surface area and total pore volume of 633.30 m2/g and 0.34 cm3/g, respectively for MG removal; and 483.07 m2/g and 0.26 cm3/g , respectively for ATN adsorption. All adsorbents best fitted to the n-BET isotherm model, suggesting a multilayer adsorption for all systems. Gasified rubber tree root-based AC (GRTRAC) and GGSWAC showed higher maximum saturation capacity (Qe) of 259.49 and 120.57 mg/g, respectively for MG and ATN adsorption at 30ºC. The AC derived from gasified oil palm empty fruit bunches (GOPEFBAC) showed reasonably high removal of MG with Qe value of 219.39 mg/g. Kinetic studies showed that all system followed Avrami model with film diffusion was the rate-limiting step controlling MG removal, while film diffusion and chemisorption controlled the ATN adsorption. Thermodynamic study confirmed that all systems, except ATN-GRTRAC were endothermic in nature. For the column studies, the better correlation of breakthrough data shown by Thomas and Yoon-Nelson model. Results indicated that GGSWAC was the best adsorbent due to its high adsorption performance for both MG dye and ATN removal
SHARED DECISION MAKING IN ANTIDEPRESSANT USE AMONG PATIENTS WITH MAJOR DEPRESSIVE DISORDER: TOOL ADAPTATION AND IMPLEMENTATION
No full textPatient-centred care (PCC), patient engagement, and shared decision-making (SDM) are increasingly known as contributors to health services quality improvement. This study aims to adapt a shared decision-making (SDM) tool, which is relevant, systematic and easy to administer by psychiatrists during their consultations on the antidepressant use among patients with major depressive disorder (MDD). There are four phases in this study, which include qualitative and quantitative methods. The first phase was related to the scoping and narrative review of the literature. The findings from this phase were brought forward to the subsequent phases of this study. Then, the second phase followed with the focus group discussions study (FGD) involving patients and psychiatrists in a psychiatric department of University Malaya Medical Centre (UMMC). This qualitative study aimed to develop a strategic tool that was informed by psychiatrists’ and patients’ perspectives toward the promotion and implementation of SDM in the use of antidepressants among patients with MDD. Next, the third phase of this study included a multicentre cross-sectional study of 15 public and private psychiatric outpatient clinics to investigate the depressive disorder patients’ and psychiatrists’ perceived involvement of the SDM process during outpatient clinic consultations. Finally, during the fourth phase of this study, the involved psychiatrists in the previous phase study were invited to become the clinical expert panels in reviewing the feedback of the last multicentre study. The scoping review of the literature was conducted using PubMed, CINAHL and Cochrane. Out of 494 records identified, a total of 13 articles were included in the scoping review. SDM was found to be a critical feature of patient-centred communication. The narrative review also provided some useful information regarding the use of antidepressants for physical and psychological symptoms in cancer. From the FGDs, patients’ and doctors’ views on providing the information needed for SDM practice were organized into six major themes; summary of treatment options, correct ways of taking medication, potential side effects of treatments related to patients, sharing of case study related to the treatment options, cost of treatment options, and input from pharmacists. For the multicentre study, a total of 160 patients (60 males and 100 females, mean age ± SD: 37.1 ± 14.2 years) were included as the subjects of this study. SDM-Q-9 total score (median score ± SD: 82.2 ± 15.4 transformed scores) indicated a high degree of perceived involvement, with statistically significant different perceptions, stratified by ethnicity, religion and employment status. Differences were further observed when item by item analysis of SDM-Q-9 and SDM-Q-Doc was applied. Finally, a booklet of scripts for doctors to conduct SDM in the use of antidepressants among MDD patients had been produced by an expert panel in the fourth phase of this study. A relevant, systematic and easy to administer booklet of scripts for psychiatrists to conduct SDM had been adapted from thorough four phases of the study. Future research should include the development of patient decision aid, specific to this type of population
LITERASI MEDIA DAN KONSTRUKSI IDENTITI DALAM TALIAN DALAM KALANGAN PENGGUNA FACEBOOK
No full textSetiap individu mempunyai identiti tersendiri sama ada di luar talian mahupun dalam talian. Identiti kendiri yang dikonstruksi memiliki keunikan serta perbezaan tersendiri yang membolehkan individu dikenali oleh orang lain. Walaupun terdapat banyak kajian yang mengkaji konstruksi identiti kendiri, khususnya dalam bidang komunikasi silang budaya tetapi faktor-faktor yang digunakan oleh individu dalam membentuk identiti dalam talian belum diterokai sepenuhnya. Kajian ini menyelidik bagaimana pemilik akaun Facebook menggunakan literasi media dalam mengkonstruksi identiti dalam talian. Objektif kajian ini adalah untuk menganalisis bagaimana pengetahuan, emosi dan kemahiran membantu individu mengkonstruksi identiti kendiri dalam talian. Dengan mengaplikasi perspektif interaksi simbolik, kajian ini mengembangkan korpus ilmu teori identiti dengan menggabungkan tiga faktor literasi media dalam konstruksi identiti dalam talian. Kajian ini menggunakan kaedah penyelidikan campuran untuk menyelidik bagaimana literasi media digunakan dalam mengkonstruksi identiti sebenar, unggul ataupun samaran dalam talian. Seramai 400 pelajar yang mengikuti program komunikasi di Universiti Kebangsaan Malaysia, Universiti Malaya, Universiti Putra Malaysia dan Universiti Sains Malaysia dipilih sebagai responden dalam kajian tinjauan. Mereka menjawab borang soal selidik yang mengukur hubungan pemboleh ubah tidak bersandar dan bersandar dalam kajian ini. Temu bual kumpulan fokus dengan sekumpulan pelajar terpilih menyusuli kaedah tinjauan. Dapatan kajian mendapati literasi media digunakan oleh seseorang untuk mengkonstruksi identiti dalam talian. Identiti sebenar dikonstruksikan dengan menggunakan pengetahuan am, pengalaman, emosi sedih dan marah serta kemahiran. Identiti unggul ditentukan oleh pengetahuan am, penapisan bahasa, selain emosi teruja dan gembira serta penggunaan gambar sebenar. Manakala identiti samaran ditentukan oleh penulisan status, emosi marah dan takut serta kemahiran mengubah suai status dan gambar. Hasil kajian merumuskan bahawa faktor literasi media yang berbeza digunakan dalam membentuk identiti sebenar, unggul ataupun samaran seseorang individu dalam talian. Kajian masa depan disyorkan melihat penerimaan orang lain terhadap identiti yang dikonstruksi oleh individu dalam talian
Numerical Simulation For Polymer Blend Using Openfoam
No full textThis thesis models the flow behaviour of polymer blends using a new constitutive model derived from tube theory and double reptation called the bidisperse Rolie-Double-Poly equation (Boudara et al., Journal of Rheology, 63, 71 (2019)) in two different geometrical flows using finite-volume based OpenFOAM software. This model incorporates the molecular mechanisms of reptation motion, thermal and convective constraint release, chain stretch and accounts for the interactions between polymer chain of different lengths in a
polydisperse melt. In this thesis, the model was implemented within OpenFOAM using the RheoTool library. This implementation was validated against published results for the transient extensional viscosity. Numerical simulations for the bidisperse Rolie-Double-Poly were performed for two different flow geometries used to characterise extension flow properties, the hyperbolic contraction and a cross-slot with both sharp and hyperbolic corners. For each flow the effects
of varying the geometric details, the flow-rate and composition of the blend are examined. In addition, we compare the results to those obtained from the equivalent multimode Rolie-Poly model that is based on linear superposition to distinguish the coupling effect predicts
by the Rolie-Double-Poly model. The study of the cross-slot flow is extended to investigate the symmetry-breaking bifurcation for a single mode Rolie-Poly and bidisperse Rolie-Double-Poly model. We find that the bifurcation to a steady asymmetric flow depends on the ratio of the stretch to orientation relaxation times and is not observed when this ratio is small even for high Deborah numbers in the Rolie-Poly model, but is observed in blends described by the Rolie-Double-Poly model
Development Of Sustainable Bricks Utilising Solid Waste Fly Ash And Paint Sludge
No full textUncontrolled infrastructure development may produce excessive carbon emission and scarcity of natural resources that are exploited for development. The reuse of waste materials in general promote material ecology and the cradle to cradle concept. The utilisation of waste from industry in the development of advanced materials has been the researcher’s aspiration to create eco-accommodating building components. The main objective of this research was to investigate the potential of utilising local industrial waste, for the development unfired bricks, evaluate, the mechanical, properties, durability and environmental performance to develop the material profile for sustainable unfired bricks. Solid Waste Fly Ash (SWFA) and Paint Sludge (PS) as target material replacing laterite soil that is non-renewable natural resources. During the preliminary stage of the research, compacted cylinder of 4 systems as target materials consists of Laterite clay (LC) and SWFA on its own as control, combination of LC with SWFA (LS) at 50:50 ratio, and to enhance sustainability, the combination of LC with SWFA and PS (LSP) at 50:25:25 ratio were investigated. Compacted cylinders of these target materials stabilised with Hydrated Lime (HL) and Ordinary Portland Cement (OPC) on its own and incorporating Ground Granulated Blast Furnace Slag (GGBS), (HL: GGBS and OPC:GGBS) both at 50:50 ratio at 10%, 20%, 30% and 40% stabiliser dosage. The cylinders are made under controlled laboratory conditions and cured for 7, 28, and 60 days prior to unconfined compressive strength (UCS) and water absorption tests. Results indicated that 30% stabiliser dosages achieved better strength and economical in optimal usage of OPC. With this preliminary results, pilot industrial and commercial trials are then carried out using full size unfired bricks of 225mm x 102mm x 65mm. These trials demonstrated that all key parameters of compressive strength, tensile strength, durability, water absorption, thermal and acoustic properties were within the acceptable engineering standards of masonry units for unfired clay bricks with the system of LSP with blended stabiliser HL-GGBS recorded the best engineering performances. The test results obtained from this investigation suggest that there is potential in the use of SWFA and Paint Sludge as substitute to clay for unfired bricks especially for the mix of LSP bricks stabilised with Lime:GGBS stabiliser. This will certainly contribute to the effort of recycling of SWFA and Industrial Sludge (Paint Sludge and possibly others) and hence to minimise the impact of these by-product landfills on the environment. The manufacture of unfired bricks/blocks able to exploit locally available waste materials is a viable alternative instead of fired bricks, especially in certain applications of low-load bearing situation. It also suggests innovation and enhanced waste management and contribution towards the concept of green building has been made in this research study. Simultaneously this helps in the reduction of unrenewable clay usage to produce bricks. Furthermore, the energy usage and hazardous emissions of the firing process from bricks making will be minimised if not eliminated
A Modified Location Housing Affordability Index of Low and Middle Income Households Urban Areas Of Malaysia
No full textGlobally, affordability is vital for the housing market. During the past few years, urban housing in Malaysia has inclined towards severely unaffordable prices. Housing affordability is to ensure that houses offered are affordable for every income groups,
especially the low and middle-income households. If the location is included as part of housing affordability criteria, can house affordability be changed? When location is taken into consideration, would housing affordability be different between two income households? The definition together with the quantifying of housing affordability uses household income, and housing expenditure has disregarded transportation expenditure which forms a substantial amount of household expenditure. There are needs to include location as part of the housing affordability. Location of housing project will ultimately
influence transportation expenditure. This research aims to determine the housing affordability by applying a simplified Location Housing Affordability Index on low and middle income households in urban areas of Klang Valley. The scope and limitation of the research are within low and middle income households’ housing and transportation expenditure and relate the housing affordability to location. This research quantitatively
examines three urban areas within the Klang Valley which are Kerinchi, Subang Bestari and Putra Heights, selected based on their distances to Kuala Lumpur as an employment centre. By combining both housing and transportation affordability, a simplified Location Housing Affordability equation has been created to indicate the housing affordability of 434 respondents from low and middle-income households answering a
questionnaire survey from the selected urban areas. Using PLS-SEM, this research has identified a relationship between the household income, housing expenditure and transportation expenditure with Location Housing Affordability Index. The findings suggest that the overall location of the urban areas in Malaysia for the low and middleincome households is very unaffordable. In the same time, the finding also suggest that
an urban area near (Kerinchi) to employment centre is deemed to be affordable, for intermediate (Subang Bestari) and further (Putra Height) from employment centre are very unaffordable. The recommendation is to propose a simplified equation of the
Location Housing Affordability Index as a measuring tool to determine housing affordability in Malaysia. Furthermore, it recommends enhancing housing rental market close to employment centres in relation to location and transportation expenditure. Moreover, the impact of location on housing expenditure needs to be included in the calculation of affordable housing
COMPARISON BETWEEN INJECTABLE AND IMPLANTABLE COMBINATION OF MESENCHYMAL STEM CELLS, PLASMA RICH PLATELET AND CERAMIC IN TREATMENT OF CRITICAL SIZE LONG BONE DEFECT
No full textBackground: The treatment of critical long bone defect remains a challenge in orthopaedics surgery. Even though gold standard is autologous bone grafting, tissue engineered bone has been widely experimented to provide alternative to the standard practice for treatment of long bone defect.
Methodology: A prospective comparison study to determine and compare efficacy between implantable and injectable combination of autologous mesenchymal stem cells (MSC), hydroxyapatite/ tri-calcium phosphate (HA/TCP) scaffold and plasma rich platelet (PRP) was conducted on six rabbits. A 1.7 cm unilateral critical segmental radius defect was done and subsequently intervention was divided into injectable and implantable group. The intervention was done after 3 weeks when no spontaneous bone healing occurred. Radiological assessment in term of serial radiograph and micro computed tomography (CT) was performed up to 12 weeks post intervention. The specimens were sent for histopathological examination for evidence of new bone formation.
Results: No bone union was observed in both group. However, bone healing was evident in both group. There was relatively significant amount of new bone was found in implantable group.
Conclusion: Implantable composite was better alternative compared to injectable composite in term of bone healing in critical long bone defect
COMPARATIVE GENOMICS ANALYSIS AND MOLECULAR CHARACTERIZATION OF COMMUNITY AND HOSPITAL-ASSOCIATED METHICILLIN-RESISTANT Staphylococcus aureus
No full textPublished genomics data regarding CA-MRSA and HA-MRSA isolates from Malaysia are scarce. Therefore, the aim of this study was to characterise the Malaysian CA-MRSA and HA-MRSA isolates in depth using molecular typing, as well as whole-genome sequencing. CA-S. aureus isolates were obtained from the nasal swabs of undergraduate students whereas HA-S. aureus isolates were archived samples obtained from hospital laboratories. Out of 168 S. aureus nasal carriage isolates obtained, the occurrence of MRSA was 8.3% and 15% among undergraduate students of the agriculture biotechnology and health sciences programmes, respectively, with multidrug resistance were observed in 15% (26/168) of the isolates. Among the 146 hospital archived samples of S. aureus, 28% (41/146) were MRSA, out of which 63% (i.e. 26/41) were categorised as multidrug-resistant (MDR; resistant to three or more classes of antimicrobial compounds).
The most predominant SCCmec type among both CA- and HA-MRSA was SCCmec-III, with the highest occurrences observed among HA-MRSA (68%; 28/41) compared to CA-MRSA (41%; 9/22) isolates. Other SCCmec types that were found in CA-MRSA were SCCmec-IV (32%), SCCmec-I (23%), and SCCmec-II (4%), while in HA-MRSA were SCCmec-IV (22%), SCCmec-V (7%), and SCCmec-I (2%). spa type t037 was the most predominantly found among CA-MRSA (50%) and HA-MRSA (61%). Higher occurrence of the pvl gene (which encodes the pore-forming Panton-Valentine
leucocidin) at 27% (11/41) among HA-MRSA compared to CA-MRSA at 23% (5/22). Another virulence factor, the staphylococcal surface protein gene (sasX), was more prevalent in HA-MRSA at 61% (25/41) compared with CA-MRSA (50%; 11/22).
Nine S. aureus isolates representing HA-MRSA (SAZ_1, SAZ_10, SAZ_16, SAZ_31, and KT/Y21), hospital-associated methicillin-susceptible S. aureus (HA-MSSA, M314250), and CA-MRSA (ZS_Z30, ZS_Z37 and ZS_Z46) were subjected to wholegenome
sequence analysis. Genomic content of all isolates were diverse with the presence of various mobile genetic elements (MGEs) such as insertional sequence (IS), transposons, plasmids, genomic islands (νSAα and νSAβ), phages, Staphylococcal
pathogenicity islands (SaPIs: SaPI1, SaPI2, SaPI3, and SaPI5) as well as both virulence and resistance determinants. In-silico, MLST and spa type of nine representative isolates revealed five sequence types (ST)-spa types combinations, i.e. ST1-t127 (M314250), ST30-t122 (SAZ_31), ST239-t037 (SAZ_10, ZS_Z30, ZS_Z37, and ZS_Z46), ST239- t421 (SAZ_1), and ST772-t657 (SAZ_16 and KT/Y21). Interestingly, one of the HAMRSA isolates, SAZ_10, harboured a novel 35 kb conjugative plasmid designated pSAZ10A that carried multiple antimicrobial resistance (AMR) determinants (aadD, ileS, and tcaA) as well as complete conjugative transfer (tra) genes.
Genome analyses showed the presence of multidrug efflux pumps and AMR genes, which were likely to contribute to the MDR phenotypes in these isolates. Moreover, various virulence factors were revealed among both CA and HA-MRSA isolates, which were likely to play essential roles in their pathogenesis. Pan-genome analysis of all representative isolates and other 49 global reference strains revealed an open genome with a large accessory genome allowing acquisition of exogenous DNA and facilitating successful adaptation to the selective hospital and community environment.
Thus, this analysis provided us an insight into the characteristics and adaptability related to both virulence and resistance of MRSA and MSSA of Malaysian isolates, which will assist in the surveillance, prevention and control of pathogenic S. aureus particularly in community- and hospital-associated environment
ALUMINUM SULPHATE DOSAGE CONTROL FOR ARTIFICIAL CLAY WATER FILTRATION USING MODEL PREDICTIVE CONTROLLER (MPC)
No full textFlood is commonly considered to be an overflow of a large amount of highly turbid water. In some cases, the flood is filtered to be used as a portable water source. In the conventional method, the flood has been treated using Aluminum Sulphate (alum) as a coagulant. The main problems associated with the conventional method are long treatment duration and difficulty to determine the optimum coagulant dosage for the desired turbidity level. Moreover, high sediment levels in the flood can reduce the lifespan of the filter as it requires regular backwashing. In light of this matter, the study is focused on a multidisciplinary approach relating to environmental engineering and electrical control engineering to produce an efficient turbidity removal system. The main objective of this study is to regulate Aluminum Sulphate dosing for optimal water filtration under various water turbidity conditions. The scope of the research involved the development of a process control system based on the combination of alum and water filters technique to remove turbidity from the water. An artificial flood using clay water was treated using an innovative Smart Tube Aqua Filter (STAF) system equipped with a special filter tube staging for coagulation and flocculation process. The STAF process is controlled using a single-input-single-output (SISO) system that has a single input from the turbidity sensor and an analog control valve as an output for optimum alum dosing control. Thus, the efficiency of the turbidity removal process was improved through the implementation of a proper dosage control technique. The system performance was evaluated based on transient response such as settling time, rise time and percentage of overshoot. The water turbidity exhibits nonlinear behavior, thus three suitable controllers namely Proportional Control (PI ZN, PI CC, PID ZN and PID CC), Self-Tuning Fuzzy PID (SFTPID) and Model Predictive Control (MPC) were implemented in order to compare the transient response. While for simulation modeling, First-Order-Plus-Dead-Time (FOPDT) model was applied to represent the STAF plant characteristic behavior and the system dynamics. From the result, MPC has exhibited the best transient response in all categories of the test (step, set point change, and load disturbance) during the simulation test. The result was consistent with previous studies that demonstrated MPC greater capability in handling the nonlinearity process compared to the conventional and other control techniques. The proposed system was implemented in an experimental validation application for evaluation purposes, and the finding validated MPC high performance in terms of transient response. As a result, in simulation for step test, shows that MPC managed to produce improved of rise time, settling time and percentage of overshoot compared to PID ZN, with the difference of 31.97 min faster for rise time, 30.14 min faster for settling time and reduction of 18.88 % for percentage overshoot. Identically to experimental validation step test found that again MPC managed to produce better results compared to PID ZN, wherewith difference of 31.97 min faster for rise time, 30.14 min faster for settling time and reduction of 18.88 % for percentage overshoot. Although there was a slight difference in the amount of each test performed, however, it did prove that MPC has advantages over PID ZN in both simulation and experimental validation. Therefore the implementation of MPC is highly recommended for turbidity removal especially in flood treatment
Scanning Electron Microscopy Study Of Novel Biomaterial Antibiotic Delivery System For Treatment Of Osteomyelitis In New Zealand White Rabbit (Nzwr) Model
No full textTreatment of osteomyelitis is still evolving in orthopaedics. The aim of this study is to evaluate the treatment of osteomyelitis using Gentamicin impregnated biomaterials in New Zealand White Rabbit (NZWR) model. Osteomyelitis was created by inoculation of Staphylococcus aureus ATCC 25923 into the drilled distal femur of NZWR. Thirty-four (34) NZWR were used during the study. They were divided into two groups Hydroxyapatite (HA) vs Calcium sulphate, (CaSO4) ) with four subgroups at weeks 3, 6, 12 and 26. The response of the treatment with Gentamicin impregnated biomaterials Hydroxyapatite (HA) and Calcium sulphate (CaSO4) against the infection were evaluated through Scanning Electron Microscope (SEM). The rabbits were sacrificed at intervals to evaluate the healing process of the affected bone. The results showed osteomyelitis changes of the rabbit at 3,6,12 and 26 weeks. SEM findings showed the presence of CaSO4 biomaterial at 3, 6 weeks and absent at 12 and 26 weeks. HA is present until 26 weeks. Biofilm is visible under SEM in HA group at 12 and 26 week. At week 26, features of marked osteolysis activity suggesting recurrence in the CaSO4 group. At week 26, there are fewer osteomyelitis changes and more remodelling of the bone in the HA group as compared to CaSO4 group. Gentamicin impregnated HA showed good osseointegration, biocompatibility and slower dissolution compared to Gentamicin impregnated CaSO4. In conclusion, these findings suggest that Hydroxyapatite shows significant potential as a drug delivery system in the treatment of osteomyelitis due to its slower dissolution. This study also highlights the importance of longer duration of assessment in experimental osteomyelitis due to potential of recurrence