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Stretchable electronic devices are progressively deployed in many applications of mechanical, electrical, and biomedical engineering. These circuits are made of stretchable and flexible substrates, as well as conductive ink and various electronic components. The choice of components and layouts for the substrate and conductive ink can regulate the stretchability of stretchable circuits. On top of that, the substance utilized to create the conductive ink must have high electrical conductivity and strong adherence to the substrate in order to produce a high-quality stretchable printed circuit. Thus, this study focused on the development of stretchable conductive ink using silver powder as a conductive filler and PDMS-OH as a binder. The mechanical properties of the synthesized ink were investigated via a simple uniaxial tensile testing method and nanoindentation technique, respectively. Accordingly, the modulus of elasticity, tensile stress and yield stress of the ink were obtained as 5.72 MPa, 1.195 MPa, and 0.86 MPa, congruently at 137% strain before undergoing failure. The experimental stress-strain data was then employed on the elastic-plastic constitutive model to investigate the elastomeric properties of the ink as it is an alternative method of lengthy and expensive procedures of validating different polymers. Moreover, the hardness and reduced modulus of the ink were evaluated by the nanoindentation method using a 5 mN maximum load with 0.5 mN/s loading/unloading rate and 2 secs holding time. Consequently, the hardness and reduced modulus values were obtained as 1.45 MPa and 34.53 MPa, respectively. These values were further validated by the Oliver-Pharr method and were in good agreement. [ABSTRACT FROM AUTHOR]

Coral reefs in Southeast Asia are becoming progressively degraded due to the natural and anthropogenic disturbances which lead to poor water quality threatening the reefs' health. Coral disease is one of the threats to the coral reefs worldwide but research on coral disease in Southeast Asia is relatively scarce especially on bacterial community associated with the disease. The destructive coral black band disease (BBD) can be found widely in the southern region of the South China Sea, Malaysia. This study aims to compare the microbial communities of healthy and BBD-infected coral tissue from two different coral species Montipora turtlensis and Acropora spicifera collected at the Shark Point of Pulau Redang, Terengganu. The bacterial isolated from corals nubbins were examined by combining culture-dependent method and bacterial sequencing of 16S rDNA. A total of 18 bacteria isolates were identified from both species of coral tissue samples prior to sub-culturing colonies samples. The sequences detected were derived from a wide taxonomic range, including representatives of Actinobacteria, Furmicutes and Proteobacteria phyla. Bacteria belonging to the phyla Proteobacteria were further divided into alpha and gammaproteobacteria. Most of the bacteria identified can be found on healthy and BBD-affected coral tissue samples; however, there are few bacteria which can be only found on BBD-affected tissue of respective coral species such as Lelliottia sp., Salnicola salarius and Microbacterium petrolearium for M. turtlensis while Pseudomonas stutzeri and Erythrobacter sp. for A. spicifera. [ABSTRACT FROM AUTHOR]

To mitigate adverse effects of ocean warming on coral reef degradation, resource managers increasingly explore management and regulation of local stressors to strengthen coral resilience and recovery. Comprehensive assessments and monitoring efforts offer a holistic understanding of reef dynamic ecosystems. In this study, we documented the distribution of benthic foraminiferal assemblages surrounding Pulau Redang, Malaysia, and assessed their potential for monitoring coral reef health using the Foraminifera in Reef Assessment and Monitoring (FoRAM) Index. Undeveloped (R1-R3) and developed (R4-R6) reef sites revealed distinct differences in reef conditions. Foraminiferal distribution showed Amphistegina lessonii (14-34%) as the dominant species, followed by Calcarina hispida (21%) and Calcarina mayori (19%). The Q-mode cluster analysis classified the distribution of foraminiferal assemblages in Pulau Redang into four sub-groups based on the reef ecological conditions. Group A1 and A2, represent the foraminiferal assemblage on the undeveloped west side of the island where live coral cover was >30%. Meanwhile, Group B1 and B2 represent the assemblage found in developed coastal regions with low live coral cover (≤20%). Additionally, the CCA results revealed a substantial influence of substrate type on the distribution of benthic foraminifera in the reef environments of Pulau Redang. FoRAM index consistently yielded high values across the study area despite varying coral reef conditions, probably due to the prevalence of Calcarina mayori in mesotrophic reefs (R4-R6), potentially distorting FoRAM values and providing a misleading indicator of reef conditions. The Modified Foram Index (MFI), calculated by excluding calcarinids, classified R3, R4, and R6 as less conducive for reef growth, aligning better with observed reef conditions. We recommend calibrating the FoRAM Index, particularly in mesotrophic reefs where calcarinids dominate foraminiferal assemblages, to enhance its precision and reliability for coral reef health monitoring and assessment within the region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This paper presents the observations of predation by the grouper Epinephelus quoyanus on sea turtle hatchlings in Chagar Hutang bay, Redang Island, Malaysia. Two of the eight collected specimens had hatchlings in their guts, whereas the remaining specimens had empty stomachs. This field report provides an in-depth understanding of the E. quoyanus diet and new insights into its feeding behavior., (© 2024 Fisheries Society of the British Isles.)

Malaysia is bounded by the South China Sea with many islands that support species megadiversity and coral reef ecosystems. This study investigates the distribution of microplastics (MPs) in the surface water around the four marine park islands (Perhentian, Redang, Kapas, and Tenggol) during COVID-19. The global pandemic has reset human activities, impacting the environment while possibly reducing anthropogenic contributions of microplastic pollution near the South China Sea islands. It was found that Pulau Perhentian recorded the most abundance of MPs (588.33 ± 111.77 items/L), followed by Pulau Redang (314.67 ± 58.08 items/L), Pulau Kapas (359.8 ± 87.70 items/L) and Pulau Tenggol (294.33 ± 101.64 items/L). Kruskal-Wallis analysis indicates a significant difference in total MPs abundance between islands. There are moderate correlations between salinity, pH, temperature and MPs variability. Among these parameters, only temperature is significant (p < 0.05) as proven by the principal component analysis and multiple linear regression analysis. Nearly 99 % of MPs are fiber type, with the majority of them being black and transparent. Micro-FTIR spectroscopy revealed polyethylene, polypropylene, polyvinyl methyl ether, polyamide, phenoxy-resins and polyurethane-acrylic are associated with MPs. The findings provide a new baseline reference for the MPs distribution on Malaysian islands, which contributes to a potential future direction regarding marine sustainability., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Zainudin Bachok reports financial support was provided by Marine Park and Resources Management Section, Department of Fisheries Malaysia (DOF), Malaysia. Yusof Shuaib Ibrahim reports article publishing charges was provided by Universiti Malaysia Terengganu., (Copyright © 2023 Elsevier Ltd. All rights reserved.)