422 research outputs found
Isolation and potential culture of phytoplankton live feed for freshwater mussels Sinanodonta woodiana (Lea, 1834)
Background and Objective: Gastropod and Bivalves are widely known as filter feeders which used to feed the phytoplankton and other micro creatures. This study was conducted to identify, isolate and determine the potential culture of phytoplankton species for mussel culture. Materials and Methods: The phytoplankton identification and the culture of phytoplankton in ponds in UPMKB, Sarawak, Malaysia were studied for a period of 3 months from February 2019 to May 2019. Results: Three genera were recorded from the ponds namely Selenastrum sp. followed by Licmophora sp. and Gloeocapsa sp. The highest abundant genus was Licmophora sp. due to their presence in every pond while the highest composition in culture condition was Selenastrum sp. because every treatment had this genus. The impact of physicochemical parameters on phytoplankton compositions and abundances in four ponds in UPMKB was assessed. Water quality parameters, such as temperature, dissolved oxygen, pH and conductivity were measured in situ from the ponds. Phytoplankton compositions and abundances were analyzed in the laboratory. ANOVA result of the physicochemical parameters showed the presence of significant difference among pH and temperature between ponds. Conclusion: The study concluded that the presence of the Selenastrum sp. genus could be the biological indicator of the water quality ponds. The best culture of phytoplankton shown by using the fertilizer treatment which was NPK fertilizer that improves the distribution of the culture of the phytoplankton
THE MOLECULAR APPROACH REVEALS THE RELATIONSHIP AMONG VENUS CLAMS ( Meretrix spp.) COMMUNITY IN MALAYSIA
Molecular study is important to detect variations and similarities among species from the same genus, in case if they do not encompass any morphological or physiological differences. The study was conducted to differentiate among species of Meretrix spp. (Meretrix lyrata, M. meretrix, and M. lusoria) obtained from two locations in Malaysia through the phylogenetic tree. The adductor muscle tissues were used to extract DNA and to perform other procedures; the samples were subjected to analyses using PCR and gel electrophoresis. The multiple sequence comparison was conducted by MUSCLE and the phylogenetic relationships were established using Maximum Likelihood (ML) statistical methods with MEGA 6.0 statistical software. M. lyrata samples showed 99% similarity to the three accessions sequence, where M. lyrata indicated 87% similarities, and M. meretrix showed not more than 89% similarities from the deposited sequence. The nucleotide base composition sequences consisted of the mean of Thiamine (T) 37.9%, Cytosine (C) 15.4%, Adenine (A) 27.4%, and Guanine (G) 19.4%. Maximum Likelihood (ML) analysis was conducted using the Tamura 3-parameter model to establish five major clades on Meretrix spp. and two out-groups clades significantly different from the Meretrix spp. These major clades were closely related to each other at the 50% evidence of bootstrap, which grouped as genus Meretrix. The present study on Meretrix spp. from the Sarawak locality was able to differentiate COI sequences between M. lyrata, M. meretrix, and M. lusoria. M. lusoria was close related to M. meretrix with strong bootstrap supporting evidence at 96% scoring. Moreover, M. lyrata was inferred as the ancestor to M. meretrix, and M. lusoria from Sarawak, Malaysia
Trends in Seagrass Research and Conservation in Malaysian Waters
The seagrass ecosystems found in the marine and coastal areas, with substantial economic and ecological services and span all over the globe excluding the Antarctic region. The Coral Triangle and Southeast Asia are recognized as a worldwide hotspot of seagrass species and habitats, encompassing 10-21 species of seagrass in every nation, although the study, understanding, and quantity of publications on seagrass ecosystems are rather limited in the region, including Malaysia. Malaysia contains 18 seagrass species from three families, which occupy 16.8 km2 of coastal area, where the study and discovery of seagrass species and meadows began in 1904 with the report of Beccari. All of the published papers reviewed reported on Malaysian seagrass-related research, which was divided into nine topic groups: biology and distribution, carbon sequestration, fauna, remote sensing, impact and pollution genetic study, restoration, microbiological investigation, and others. The extensive study of the seagrass ecosystem began in 1993, and we have identified 183 published papers from Scopus, 141 publications from Web of Science, and 42 from Google Scholar. However, the average trend of the number of publications from 1993 to 1999 was 0.71 ± 0.36, while from 2000 to 2022 was 7.70 ± 1.16 followed by the average trend of the yearly number of publications was 6.78 ± 1.08. The highest number of publications was found on faunal categories (43.17%), followed by biology and distribution (21.85%). The number of articles that were published on Malaysian seagrass meadows each year has been discovered to be rising, which indicates that the trends in seagrass study and publishing were progressively garnering the attention of researchers, academics, and the government. However, to better understand the sustainable ecology and ecosystem services provided by seagrass habitats, an emphasis on certain research niches, such as the genetic study of flora and fauna in seagrass meadows, microbial ecology, and restoration as well as conservation of seagrass species might be helpful.22 página
Short note:The fecundity and egg size of the freshwater crab(Isolapotamon bauense Ng,1987)from Sarawak, Borneo
The Island of Borneo harbors a high species richness of freshwater brachyurans, many of which are endemic in the region and their existence is threatened by an thropogenic activities. Our knowledge on the fundamental aspects which are required for species conservation assessment is currently limited. For instance, information on fecundity of most Bornean freshwater crabs is almost non-existent despite this being an important predictor of vulnerability to extinction. This paper describes the fecundity and egg size of the giant freshwater crab(Isolapotamon bauense Ng,1987)from Kuching Division in Sarawak, Borneo. The fecundity of the crab is between 26and 81 eggs, with the egg diameter ranging between 3.7–4.2 mm. The macrolecithal eggs are attached to the pleopods of the female abdominal brood pouch;they are bright orange and are comprised of two layers of membrane, with a thicker outer layer and a thinner inner layer,encapsulating the large embryonic yolk sac
Benthic macrofaunal assemblage in seagrass-mangrove complex and adjacent ecosystems of Punang-Sari Estuary, Lawas, Sarawak, Malaysia
Present study dealt with the on faunal and in faunal assemblage from seagrass bed, mangrove area, and adjacent non-mangrove and seagrass (NMS) in Punang-Sari estuary, Lawas, Sarawak, Malaysia. Samples were collected from June to July 2019 by using quadrates and handpicking from the outside the sampling area to know the real checklist of surface macrofauna in this area. A ten-meter transect line was settled in three habitat areas where sampling was performed by putting three quadrates (0.35m×0.35m). Epifauna and infauna samples were collected from inside the quadrate and sieved using 0.4 mm mesh size sieve. A total of 111 species of gastropod (87 species from 30 families), bivalve (18 species from 9 families), Polychaeta (2 species), echinoderms (1 species), and crustacean (3 species) were recorded during the study period. Seagrass meadows comprised most diverse and abundant faunal (50 species) assemblage followed by mangrove habitats (48 species), and NMS (20 species). The dendrogram revealed two significant habitats in the sampling site. PCA analysis revealed, seagrass habitat sheltered a higher number of species followed by mangrove and NMS area. Jaccard similarity index revealed seagrass and mangrove habitats (0.42) contains the highest similar species amongst all habitats compared to mangrove and non-seagrass-mangrove area (0.26). Out of total species recorded (101), only ten species were reported as least concern, and 2 species hold deficient data status, and the rest are not evaluated. Bio-assemblage in seagrass habitat was found rich compared to other habitats, which could be useful for future ecological investigation and marine ranching
SYMBIOTICALLY SNAPPER SHRIMP ANCHISTUS CUSTOIDES BRUCE, 1977 (DECAPODA: PALAEMONIDAE) INHABITING THE MANTLE CAVITY OF THE PEN SHELL (BIVALVIA: PINNIDAE)
Snapper shrimp is a symbiotic organism usually hidden under the rocks,
sponges and pen shells in the seagrass and coral habitats. The relationship study within
snapper shrimp and pen shell was conducted from Merambong shoal, one of the biggest
seagrass beds in peninsular Malaysia. A total of 40 individual pen shells were collected
randomly and four species of pen shells were identified. 40 Anchistus custoides were found
inhabiting symbiotically in the mantle cavity of the pen shell as solitary males and females
and heterosexual pairs. Pen shell, Pinna bicolor and Atrina vexillum recorded the highest
average SH 217.79±53.15 mm, SV 2.62±1.36 dm3 and SH 164.10-224.78 mm with the SV
1.18±0.43 dm3, respectively compared to the other species. The size of Anchistus custoides
ranged from 15.00 to 20.00 mm in length and it was determined to be female due to the
presence of eggs in the pleopods. The length of the cephalothorax and its length were
highly related (rs=0.563, p≤0.01, N=40) and found wider in females. A little difference
in size between the left and right chela in males of identical length was noticed, although
the left chela is much bigger than the right. The significant relationship (rs=0.450, p≤0.01,
N=40) between the pen shell length and shrimp (male-female) length revealed that the size
of the shell is important to be hosted the snapper shrimp in the shell cavity
Fifteen new risk loci for coronary artery disease highlight arterial-wall-specific mechanisms
Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide. Although 58 genomic regions have been associated with CAD thus far, most of the heritability is unexplained, indicating that additional susceptibility loci await identification. An efficient discovery strategy may be larger-scale evaluation of promising associations suggested by genome-wide association studies (GWAS). Hence, we genotyped 56,309 participants using a targeted gene array derived from earlier GWAS results and performed meta-analysis of results with 194,427 participants previously genotyped, totaling 88,192 CAD cases and 162,544 controls. We identified 25 new SNP-CAD associations (P < 5 × 10(-8), in fixed-effects meta-analysis) from 15 genomic regions, including SNPs in or near genes involved in cellular adhesion, leukocyte migration and atherosclerosis (PECAM1, rs1867624), coagulation and inflammation (PROCR, rs867186 (p.Ser219Gly)) and vascular smooth muscle cell differentiation (LMOD1, rs2820315). Correlation of these regions with cell-type-specific gene expression and plasma protein levels sheds light on potential disease mechanisms
The Female Athlete's Heart: Facts and Fallacies.
Purpose of the review
For many years, competitive sport has been dominated by men. Recent times have witnessed a significant increase in women participating in elite sports. As most studies investigated male athletes, with few reports on female counterparts, it is crucial to have a better understanding on physiological cardiac adaptation to exercise in female athletes, to distinguish normal phenotypes from potentially fatal cardiac diseases. This review reports on cardiac adaptation to exercise in females.
Recent findings
Recent studies show that electrical, structural, and functional cardiac changes due to physiological adaptation to exercise differ in male and female athletes. Women tend to exhibit eccentric hypertrophy, and while concentric hypertrophy or concentric remodeling may be a normal finding in male athletes, it should be evaluated carefully in female athletes as it may be a sign of pathology. Although few studies on veteran female athletes are available, women seem to be affected by atrial fibrillation, coronary atherosclerosis, and myocardial fibrosis less than male counterparts.
Summary
Males and females exhibit many biological, anatomical, and hormonal differences, and cardiac adaptation to exercise is no exception. The increasing participation of women in sports should stimulate the scientific community to develop large, longitudinal studies aimed at a better understanding of cardiac adaptation to exercise in female athletes
Trans-ancestry meta-analyses identify rare and common variants associated with blood pressure and hypertension
High blood pressure is a major risk factor for cardiovascular disease and premature death. However, there is limited knowledge on specific causal genes and pathways. To better understand the genetics of blood pressure, we genotyped 242,296 rare, low-frequency and common genetic variants in up to ~192,000 individuals, and used ~155,063 samples for independent replication. We identified 31 novel blood pressure or hypertension associated genetic regions in the general population, including three rare missense variants in RBM47, COL21A1 and RRAS with larger effects (>1.5mmHg/allele) than common variants. Multiple rare, nonsense and missense variant associations were found in A2ML1 and a low-frequency nonsense variant in ENPEP was identified. Our data extend the spectrum of allelic variation underlying blood pressure traits and hypertension, provide new insights into the pathophysiology of hypertension and indicate new targets for clinical intervention
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