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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]

This paper presents the influence of Fe2O3 nanoparticles on the microstructure and fillet height for the ultra-fine electronics assembly in the reflow soldering process. Lead-free SAC solder paste was reinforced with different weighted percentages of Fe2O3 nanoparticles (i.e., 0.01, 0.05, and 0.15 wt.%) using a mechanical solder paste mixer. A new form of nano-reinforced lead-free solder paste was applied to assemble the ultra-fine capacitor (i.e., 01005 size) onto the printed circuit board by applying the reflow soldering method. Focused ion beam (FIB), high-resolution transmission electron microscope (HRTEM) system equipped with energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (EDS), and nanoindentation tester, were all used to examine the microstructure, hardness, and the fillet height of the solder joints. The experimental results revealed that nano-reinforced solder with the content of 0.01, 0.05, and 0.05 wt% yielded small changes in the intermetallic layers. Furthermore, applying an increment of Fe2O3 to 0.05 wt% also improved the fillet height. The mechanism of the agglomeration of Fe2O3 in the bulk solder is discussed in this study. Moreover, simulation analysis using the volume of fluid (VOF) and discrete phase method (DPM) was both employed to describe the mechanism of nanoparticle distribution in the solder and the reflow soldering process. The findings are expected to provide profound knowledge and further reference towards the reflow soldering process of the miniaturised electronic package. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of cyclic loading on structural integrity of a P91 specimen at high temperature. The experiments were conducted using a thermomechanical fatigue test machine at 600 °C and electron microscopy investigation. The evolution of the elastic modulus can be used as an indication of the strength degradation of the material. Scanning and transmission electron microscopy were used to investigate the microstructural variations that occurred in the specimen at different life fractions during the cyclic tests. Based on the experimental stress-strain data, variations in the Young's modulus and the area enclosed in the hysteresis loops were determined, together with the variations in other parameters throughout the test. The initiation of cracks begins in the second stage of cyclic softening. The changes of structure, on a micro-scale, do not significantly affect the strength of the specimen, as the Young's modulus values of the specimen remain approximately constant up to the end of the stage 2 cyclic softening before damage to the specimen starts to increase. The cracks cause the material to become weaker, as indicated by the decrease of the Young's modulus value. The evolution of damage was found to be significant in the final stages of softening owing to the propagation of cracks in the P91 steel affecting the integrity of the material. [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.)

Irgarol 1051 and diuron are photosystem II inhibitors in agricultural activities and antifouling paints in the shipping sector. This study focused on three major ports (western, southern, and eastern) surrounding Peninsular Malaysia to construct the distribution of both biocides on the basis of the seasonal and geographical changes. Surface seawater samples were collected from November 2011 to April 2012 and pretreated using the solid-phase extraction technique followed by quantification with GC-MS and LC-MS-MS for Irgarol 1051 and diuron, respectively. Generally, the distribution of Irgarol 1051 was lowest during November 2011 and highest during April 2012, and similar patterns were observed at all ports, whereas the distribution of diuron was rather vague. The increasing pattern of Irgarol 1051 from time to time is probably related to its accumulation in the seawater as a result of its half-life and consistent utilization. On the basis of the discriminant analysis, the temporal distribution of Irgarol 1051 varied at Klang North Port, Klang South Port, and Pasir Gudang Port, whereas diuron was temporally varied only at Kemaman Port. Furthermore, Irgarol 1051 was spatially varied during November 2011, whereas diuron did not show any significant changes throughout all sampling periods. Ecological risk assessment exhibited a high risk for diuron and Irgarol 1051, but Irgarol 1051 should be of greater concern because of its higher risk compared to that of diuron. Thus, it is recommended that the current Malaysian guidelines and regulations of biocide application should be reevaluated and improved to protect the ecosystem, as well as to prevent ecological risks to the aquatic environment., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This article provides raw datasets of the coral reefs status in Pulau Bidong, southern of South China Sea before and after being strike by the tropical storm Pabuk on January 2019. Data were collected using a rapid coral survey method called Coral Video Transect (CVT) technique. The data were collected along a 100 m transect line set up parallel to the shoreline and at a constant depth. In total, eight transects were surveyed during both periods (pre - August 2016, post - March 2019). Back in laboratory, the footage was then extracted into non-overlapping frames or still images prior to image analysis using Coral Point Count with Excel Extension (CPCe) software. The benthic coral reefs relative percentage cover was automatically generated after the image analysis and represented by five major categories; live coral (C), algae (ALG), other invertebrates (OT), dead coral (DC), and sand silt and rock (SR). Live coral cover was identified up to the genus level. This raw dataset was used in this article. The data provided in this article could be of significant use for future studies especially on coral recovery after the natural disturbances. It can provide a baseline assessment especially for coral reefs management as well as to comprehend changes in coral health status in the face of natural and anthropogenic disturbances. The data presented here support the information in the article Safuan et al. (2020)., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2020 Published by Elsevier Inc.)

This study investigates the presence of microplastics in surface seawater and zooplankton at five different locations off the Terengganu coast in Malaysia, southern South China Sea. A total of 983 microplastic particles, with an average abundance of 3.3 particles L -1 were found in surface seawater. An average of one plastic particle was detected in 130 individuals from 6 groups of zooplankton. These groups include fish larvae, cyclopoid, shrimps, polychaete, calanoid and chaetognath where they ingested 0.14, 0.13, 0.01, 0.007, 0.005 and 0.003 particle per individual, respectively. Microplastics in the form of fragments are the most common type of ingested microplastics that ranged between 0.02 mm (cyclopoid) - 1.68 mm (shrimp and zoea). Contrastingly, fibers, which are identified as polyamide are the main type of microplastics that dominate in seawater., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pulau Redang and Pulau Tioman have experienced huge tourism growth over the last two decades, but minimal sewage treatment may threaten the resilience of their coral reefs. This study uses stable isotope techniques to identify suitable bioindicators of sewage nutrients (δ 15 N) at these islands by measuring macroalgae (Lobophora spp.), gastropods (Drupella spp.), scleractinian coral (Acropora spp.), and leather coral (Sinularia spp.). At tourist hubs using seepage septic tank systems, enrichment of Acropora δ 15 N (Redang, +0.7‰) and Sinularia δ 15 N (Tioman, +0.4‰) compared to pristine background levels indicate enhanced sewage nutrient discharge. Carbon isotopes and survey data suggest that sedimentation did not confound these δ 15 N trends. Potential damaging effects of sewage discharge on the coral reef communities at both islands are highlighted by strong correlations between Acropora δ 15 N and regional variation in coral reef community structure, and exclusive occurrence of degraded reefs at regions of high sewage influence., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Background: In order to understand trophic ecology, habitat use and migration of coral reef fish, fatty acid composition and levels were examined in the bigeye snapper Lutjanus lutjanus collected in the Malaysian South China Sea., Results: Proportions of saturated fatty acids (SAFA) ranged from 55.0% to 66.5%, with the highest proportions in fatty acids, the second highest was monounsaturated fatty acids (MUFA) ranged from 30.7% to 40.2% while the proportion of polyunsaturated fatty acids (PUFA) was the lowest ranged from 2.8% to 4.8%. Palmitic acid (16:0) was the most common in SAFA, oleic acid (C18:1ω9c) was the dominant in MUFA and linolenic acid (C18:3n3) showed the highest value in PUFA. Fatty acid concentrations, especially in SAFA and MUFA, increased with fish growth, suggesting diet and habitat shifts during the fish life history. Most of the fish had more than 1 of EPA: DHA ratio, which suggested that diets of L. lutjanus tended to be higher trophic organisms such as zooplankton and crustacean in coral ecosystem., Conclusions: The diet shift revealed by the composition and levels of the fatty acid profile revealed potential pattern in the habitat use and migration scale in coral reef environment of L. lutjanus.

Background: In order to understand feeding ecology and habitat use of coral reef fish, fatty acid composition was examined in five coral reef fishes, Thalassoma lunare, Lutjanus lutjanus, Abudefduf bengalensis, Scarus rivulatus and Scolopsis affinis collected in the Bidong Island of Malaysian South China Sea., Results: Proportions of saturated fatty acids (SAFA) ranged 57.2% 74.2%, with the highest proportions in fatty acids, the second highest was monounsaturated fatty acids (MUFA) ranged from 21.4% to 39.0% and the proportion of polyunsaturated fatty acids (PUFA) was the lowest ranged from 2.8% to 14.1%. Each fatty acid composition differed among fishes, suggesting diverse feeding ecology, habitat use and migration during the fishes' life history in the coral reef habitats., Conclusions: Diets of the coral fish species might vary among species in spite of that each species are living sympatrically. Differences in fatty acid profiles might not just be considered with respect to the diets, but might be based on the habitat and migration.

In order to understand feeding ecology, habitat use and migration of coral reef fish, fatty acid composition was examined in damselfish species Abudefduf bengalensis and A. sexfasciatus collected in the Malaysian South China Sea. Proportions of saturated fatty acids (SAFA) ranged from 49.5% to 74.2%, with the highest proportions in fatty acids, the second highest was monounsaturated fatty acids (MUFA) ranged from 21.4% to 47.4% and the proportion of polyunsaturated fatty acids (PUFA) was the lowest ranged from 3.1% to 6.0%. Palmitic acid (16:0) was the most common in SAFA, oleic acid (C18:1ω9c) was the dominant in MUFA and linolenic acid (C18:3n3) showed the highest proportion in PUFA. Fatty acid concentrations, especially in SAFA and MUFA, could be related to physiological condition, sexual development, and recent feeding events. The diet shift revealed by the fatty acid composition suggests changes in habitat use and migration scale in coral reef environment of genus Abudefduf.

The use of antifouling paints to the boats and ships is one among the threats facing coastal resources including coral reefs in recent decades. This study reports the current contamination status of diuron and its behaviour in the coastal waters of Malaysia. The maximum concentration of diuron was 285 ng/L detected at Johor port. All samples from Redang and Bidong coral reef islands were contaminated with diuron. Temporal variation showed relatively high concentrations but no significant difference (P>0.05) during November and January (North-East monsoon) in Klang ports (North, South and West), while higher levels of diuron were detected during April, 2012 (Inter monsoon) in Kemaman, and Johor port. Although no site has shown concentration above maximum permissible concentration (430 ng/L) as restricted by the Dutch Authorities, however, long term exposure studies for environmental relevance levels of diuron around coastal areas should be given a priority in the future., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Emerging booster biocides contamination raises particular attention in the marine ecosystem health. This study provides the baseline data on the occurrence of Irgarol-1051 (2-methylthio-4-tert-butylamino-6-cyclopropylamiono-s-triazine) in the selected coastal water around Malaysia. The maximum detected concentration of Irgarol was 2021 ng/L at Klang West, commercial and cargo port. Coral reef Islands (Redang and Bidong) were relatively less contaminated compared to other coastal areas. The temporal variation revealed that only 1% of 28 stations sampled on November, 2011 was above the environmental risk limit of 24 ng/L as suggested by Dutch Authorities, while in January and April, 2012; 46% and 92% of the stations were above the limit respectively. The present findings demonstrate the wide detection of novel antifouling materials Irgarol-1051 which advocates the need for proper monitoring and conservation strategies for the coastal resources., (Copyright © 2013 Elsevier Ltd. All rights reserved.)