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Waste cooking oil (WCO) from various sources were evaluated as low-cost carbon feedstock to produce poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] copolymer, which is a type of polyhydroxyalkanoate (PHA). Different Cupriavidus necator transformants harbouring phaCBP−M−CPF4 were employed as PHA-producing organisms in one-stage cultivation in shake flasks. Biological and chemical recovery of PHA were evaluated. C. necator Re2058/pHT1-CBP−M−CPF4 was able to achieve a cell dry weight (CDW) of 8.5 g/L, PHA content of 75.5 wt% and PHA concentration of 6.4 g/L from 1% (v/v) WCO. The weight-average molecular weight (Mw) of the synthesized PHA obtained from the same strain was 1440 kDa. The CDW, PHA content and concentration acquired using WCO are comparable to those using fresh oils as carbon substrates. The copolymer produced from distinct sources of WCO and different extraction methods did not have significant differences in molecular weights and thermal properties. Mealworms can perform biological recovery of PHA from cells fed with WCO from distinct sources. This study suggests that WCO from any source can be used as carbon source for bacteria to produce PHA. WCO can be a sustainable alternative for the more expensive fresh oils, and the synthesized PHA can be biologically recovered by mealworms. A combination approach of utilising low-cost substrate such as WCO, high-performance PHA producer including C. necator transformants and biological recovery to extract PHA is beneficial in biosynthesis of PHA copolymer, since this can make PHA production more economical and can improve the ability of PHA to compete with conventional petrochemical plastics. [ABSTRACT FROM AUTHOR]

Since the outbreak of COVID-19, the upstream oil and gas industry has faced unprecedented challenges in terms of low prices. Given the volatility and uncertainty around oil prices, it is critical for the sector to exercise capital constraints and manage costs effectively to ensure its future success. In response to the difficulties with cost overruns, oil and gas operators have implemented various strategies and measures, such as cost reduction, project prioritisation, project delays and streamlining the supply chain and contracts. However, these approaches do not provide a sustainable or cost-effective solution in the long term. Previous research on project cost overruns has shown that internal factors, particularly project data integration, are the main cause of poor project performance and cost overruns. However, no approaches or technologies have been proposed to improve cost management or control cost overruns. This paper aims to review the features and functions of 5D BIM that could improve the integration of project data throughout the lifecycle and provide a solution for cost management in Malaysia's oil and gas upstream projects. The methodology adopted in this study ensures a rigorous and systematic approach in reviewing the literature on cost management issues, cost overruns and the role of 5D BIM. Consequently, BIM streamlines cost estimating, saves time by automating data entry and producing accurate estimates, increases productivity and promotes better collaboration within the project team. [ABSTRACT FROM AUTHOR]

The conventional geotechnical investigation method using borehole drilling and sampling was usually performed for subsurface exploration. However, it is -time-consuming, invasive and requires the closing of railway lanes that disrupts the train service. To avoid this problem, a geophysical method is an alternative that can be proposed to assess the conditions of the soil subgrade under the railway track. Electrical resistivity is one of the geophysical methods that study the nature of the electricity flow in the soil by injecting the electric current into the soil and measuring the generated potential difference. The field investigation was conducted at two different locations using electrical resistivity methods to identify the properties of the soil. Two railway track site locations selected were Pinang Tunggal, Pulau Pinang (KM 23), and Alor Setar, Kedah (250 m from the station in the north direction). ABEM Terrameter LS was used in field work that applied two configurations of an array, the Wenner and Schlumberger arrays, to infer the subsurface soil layer. The results concluded that the apparent resistivity data need to be inverted into an actual resistivity data set using Resistivity 2D Inversion (RES2DINV) software. The analysis found that the soil properties are both classified as soft soil with electrical resistivity values ranging from 0 - 100 Ω-m. [ABSTRACT FROM AUTHOR]

Tissue engineering technology aids in the regeneration of new tissue to replace damaged or wounded tissue. Three-dimensional biodegradable and porous scaffolds are often utilized in this area to mimic the structure and function of the extracellular matrix. Scaffold material and design are significant areas of biomaterial research and the most favorable material for seeding of in vitro and in vivo cells. Polyhydroxyalkanoates (PHAs) are biopolyesters (thermoplastic) that are appropriate for this application due to their biodegradability, thermo-processability, enhanced biocompatibility, mechanical properties, non-toxicity, and environmental origin. Additionally, they offer enormous potential for modification through biological, chemical and physical alteration, including blending with various other materials. PHAs are produced by bacterial fermentation under nutrient-limiting circumstances and have been reported to offer new perspectives for devices in biological applications. The present review discusses PHAs in the applications of conventional medical devices, especially for soft tissue (sutures, wound dressings, cardiac patches and blood vessels) and hard tissue (bone and cartilage scaffolds) regeneration applications. The paper also addresses a recent advance highlighting the usage of PHAs in implantable devices, such as heart valves, stents, nerve guidance conduits and nanoparticles, including drug delivery. This review summarizes the in vivo and in vitro biodegradability of PHAs and conducts an overview of current scientific research and achievements in the development of PHAs in the biomedical sector. In the future, PHAs may replace synthetic plastics as the material of choice for medical researchers and practitioners. [ABSTRACT FROM AUTHOR]

Background: Real world data (RWD) is increasingly relevant in breast cancer (BCa) as it is the most frequently diagnosed cancer. Developed world has seen improved breast cancer survival, however, RWDon BCa survival in Malaysia is still lacking. Aims and Objectives: This study aims to determine characteristics and survival of BCa patients from a single institute. Materials and Methods: Retrospective analysis of 168 BCa patients who were treated with at least one treatment modality in Beacon International Specialist Centre (BISC) from 2008-2012 was conducted. Patient characteristicsand treatments received were analysed descriptively to survival outcome. Vital status was obtained from the National Registry of Birth and Death (NRD) records. Observed survival rates wereestimated by Kaplan-Meier method and difference between groups by log-rank. Results: Of 143 eligible BCa patients,28 (19.6%) died during the study period. Five-year BCa specific survival rates were 100% for Stage I and II, 79.31% for stage III and 38.89% for Stage IV disease. In the multivariate analysis, higher stage at diagnosis, triple negative breast cancer with metastases and higher grade were associated with worse survival outcomes. The overall 5-year survival rate of BCa patients in BISC from 2008-2012 compares favourably to the survival data of developed countries. Conclusion: In conclusion, the overall 5-year survival rate of BCa patients in BISC compares favourably to the survival data of developed countries, as well as to other institutions. [ABSTRACT FROM AUTHOR]

The structures of two genes from Roseateles depolymerans strain TB-87 encoding the esterases Est-H and Est-L, which can degrade aliphatic-aromatic copolyesters, were annotated. Two open reading frames (ORFs) consisting of 1083 bp and 870 bp nucleotides, corresponding to est-H and est-L , encoding enzymes of 290 and 289 amino acids, respectively, were predicted. In addition, another ORF consisting of 735 bp encoding a chaperone-like protein (Est-Ch) of 244 amino acids was identified in the intergenic region of est-H and est-L. The presence of a promoter region upstream of est-H and the absence of a terminator region downstream of the ORF and vice versa for est-Ch , suggests that est-H and est-Ch are polycistronically expressed. A homology search for Est-H and Est-L revealed homology with plastic degrading enzymes, such as esterases and cutinases, while Est-Ch showed homology with a bacterial lipase chaperone. As consensus lipase sequences (-Gly-His-Ser-Met-Gly-) were observed in these enzymes, Est-H and Est-L were hypothesized to be hydrolases with serine (Ser) in their active center. Three-dimensional structures of Est-H and Est-L without their putative signal sequences were constructed using Est119 from Thermobifida alba strain AHK119 as the template; the structures and positions of the catalytic triad (Ser, Asp, His) active centers were similar to those of Est119. A mutant strain in which the annotated esterase-encoding genes were disrupted using a homologous recombination method lost the ability to form a clear zone on poly(butylene succinate- co -adipate (PBSA) emulsion-overlaid nutrient agar plates. Characterization of the esterases from strain TB-87 could contribute to the development of novel biodegradable plastics with unique properties such as recyclable monomers. • Est-H and Est-L showed different cleavage patterns despite having the similar substrate specificity and nearly identical molecular masses. • A chaperon gene, est-Ch , was present within the intergenic region of Est-H and Est-L's encoding genes. • A promoter and a terminator regions flanking the est-H and est-Ch ; suggests that both genes are polycistronically expressed. • est-H-est-Ch-est-L genes deficient mutant could not form halo zone on PBSA emulsion-overlaid nutrient agar plate. [ABSTRACT FROM AUTHOR]

Slope failures always occur in Malaysia especially during the monsoon seasons between October and January every year causing fatalities and damages to properties. The main factors causing the slope failure to occur are reduction of the shear strength parameters and loss of negative suction due to saturation of the slope. The objective of this study is to determine the effective shear strength parameters of the soil taken at slope failure using consolidation drain (CD) shear box and also to determine the factor of safety using SLOPE/W software. The soil samples were tested under submerged condition. The minimum value of effective shear strength parameters obtained from the CD shear box tests were c' = ° kN/m2 and ϕ' = 47.3° while the maximum value of c' = 3°.2 kN/m2 and ϕ' = 35.6 °. The FOS varied from °.377 to °.749 with minimum value of factor of safety was °.377. When using SLOPE/W software on a stable slope cross section having minimum value of effective shear strength parameters, the minimum value of factor of safety was less than 1 indicating that the slope had already failed. [ABSTRACT FROM AUTHOR]