Abstract Wood densification and alkaline pretreatment are well-known to enhance the mechanical properties and lignin-removal, respectively, especially those of low-density timber species. This study was aimed to determine the mechanical properties (static bending and compression) of untreated and alkaline-pretreated densified 3-layered Paraserianthes falcataria timbers. Pretreatment with 3%, 6% and 9% NaOH resulted in an increase up to 44% in mechanical static bending properties, where Modulus of Elasticity with 9% NaOH having the highest value in edge-wise bending, while 6% NaOH obtained the highest value of flat-wise bending. Both edge-wise and flat-wise bending showed slight increment in values for Modulus of Rupture between the concentrations. Compressive strength for compression parallel to the grain obtained by 0% NaOH (control) shows the highest value compared to other concentrations. Meanwhile, compression perpendicular to the grain of 9% NaOH enhanced for about 10% in compressive strength value compared to 0% NaOH.

Abstract The emergence of resistance in vector mosquitoes such as Aedes, mainly against pyrethroids group of insecticide, has become a serious threat to vector control management in public health services. This study aims to investigate the susceptibility/resistance status of the dichloro-diphenyl-trichloroethane (DDT), lambda-cyhalothrin, and permethrin and the presence of F1534C and V1016G knockdown (kdr) alleles mutations in Aedes aegypti populations in Kota Bharu Kelantan Malaysia. The long-lasting resistant effects of DDT against Ae. aegypti is evaluated. The F1 adults' of Ae. aegypti were collected from Kota Bharu and assayed to the WHO susceptibility test with 4% DDT, 0.05% lambda-cyhalothrin, and 0.75% permethrin. Mortality percentage, knockdown time KT50, and resistance ratio RR values were calculated for susceptibility analysis. All the mosquito survivors from the assay were kept in -80 °C and subjected to the Allele Specific-Polymerase Chain Reaction (AS-PCR) analysis on the presence of kdr mutation F1534C and V1016G. Results obtained from the assay show Ae. aegypti was resistant phenotypically against type I and type II pyrethroids viz permethrin and lambda-cyhalothrin. AS-PCR analysis however showed a resistance genotypically against pyrethroid type I only. The RR values for all insecticides tested were more than 10, which indicate resistance. The kdr mutation alleles frequencies of 1/3 F/C1534 and 2/3 C/C1534 were detected in Ae. aegypti population.

Abstract The interior forest ecosystem of Sabah is inhabited by a wide range of bat species, and yet their survivals are threatened by the loss and degradation of the interior forest habitat. The relevant past studies mainly focused onto the bat communities presented at the local permanent forest reserves, which subsequently resulted in the lacking in information on the bat communities at the local state land forests. Therefore, a preliminary bat survey was conducted to determine the bat species that inhabited the Tenghilan Community Forest, Sabah, Malaysia. Three existing forest trails were selected as the sampling areas, and then three sampling points were established along each trail. Mist-net trapping technique was used in sampling the bat individuals, and then ancillary data was recorded through visual observation, at each sampling point. A total of 36 bat individuals belonged to 6 different species and 4 different families were captured and recorded within 6 days of sampling period in this study. The trapped individuals were comprised mainly of the least-concerned (n = 34) frugivorous and nectarivorous bat species (n = 32). Among the three selected trails, the diversity richness and distribution evenness of bat species at Tongkat Ali Trail were determined to be significantly higher (H’ = 1.351; 1-D = 0.6979) than those of both the Liposu Trail and Bambangan Trail (H’ = 0, t = -11.315, p<0.001; 1-D = 0, t = 14.317, p<0.001). In summary, this state land forest serves as an important habitat for the local bat community, even though the existing local bat composition is different from that of an undisturbed forest in Sabah. Further research should be conducted onto the entire area of this state land forest, by using a longer sampling period and more sampling points in future.

Abstract Increasing concerns regarding sustainable soil improvement point towards biocementation. Different biocementation methods are in the field today. Without disturbing the soil structure and its natural habitat calcium carbonate precipitation provides soil stabilization. The bonding of particles in combination with urea, water and calcium chloride produce calcium carbonate precipitation which is applied to the soil with urease enzyme can result in the binding of soil particles. The process Enzyme Induced Carbonate Precipitation is a process using chemicals to improve soil engineering properties like strength, shear strength, permeability. The improved versions of Enzyme Induced Carbonate Precipitation with the addition of magnesium chloride, sisal fibres and biopolymer can provide high strength to soils in vulnerable conditions. Unconfined Compressive Strength test and Scanning Electron Microscopy are the tests to measure the strength and particle binding respectively in soils.

Abstract Matang Mangrove Estuaries is dominantly surrounded with mangrove vegetations, making it rich with numerous types of commercially important fish species and thus has a critical role for providing food resources and generating income for local residents. Several studies about the species availability and distribution of fish have been conducted at there but none have been conducted on assessing the Length-weight relationships (LWR) of commercially important fishes. Thus, the main objective of this study was to establish the first record of LWR of estuarine fish from Marudu Mangrove Estuaries. A total of 16 species of fish from Matang Mangrove Estuaries located in Perak, Peninsular Malaysia were selected for the study. The total length and wet weight of the specimens, totaling of about 4372 individuals and comprising of 13 families were measured and estimated. The dominant families were Clupeidae, Engraulidae and Leiognathidae with two species for each of them, and only one species each for other remaining families. Overall, negative allometric growth was observed in 15 species whereas only one species showed isometric growth. This research serves as the first record of LWR data for 16 fish species in the Malaysian waters of Matang Mangrove Estuaries. It is hoped that these findings can help researchers in extending future studies, particularly about fish population in this study area.