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Assessing the coherence in biological and environmental drivers of young sea bass abundance across important estuarine nursery areas of the northern European sea bass stock
No full textYear class strength is an important determinant of fish population size, but the
drivers are often unknown. The northern stock of European sea bass
(Dicentrarchus labrax) is an important target species for both commercial and
recreational fisheries. Scientific assessments showed a rapid decline in spawning
stock biomass from 2010-18 attributed to a combination of fishing mortality and
poor year class strength. Recruitment to the adult stock is linked to the
abundance and temporal dynamics of young bass in estuarine nursery areas,
but little is known about the relative importance of environmental and biological
drivers on the survival of these young life stages. In this study, we use Generalised
Linear Models to attempt to identify important local environmental (sea surface
temperature and river flow) and biological (chlorophyll-a concentration and
predator abundance) drivers of young sea bass abundance. We focus on seven
British and Irish estuarine areas that are important to the northern stock of
European sea bass. In four English estuarine areas there were good model fits to
the abundance of young sea bass, but predictors differed amongst these
suggesting that drivers of abundance may differ among individual nursery
areas. This was further demonstrated by poor fits of models generated for
English estuaries to interannual patterns of abundance in the Irish nursery
areas tested. The differences found in the most important abundance drivers
amongst areas highlight the complex and differing dynamics between estuaries. If the number of young bass that eventually join the adult stock is dependent
on survivors from a diverse set of unique nursery area conditions, then
endeavours to incorporate this knowledge into fisheries management
should be further explored
Biodiversity and Hemolytic Toxicity of the Genus Heterocapsa (Dinophyceae) in the Beibu Gulf, China
No full textThe dinoflagellate genus Heterocapsa includes several widely distributed and potentially
toxic species associated with Harmful Algal Blooms (HABs), particularly affecting theWestern Pacific
Ocean. To reveal the biodiversity of Heterocapsa in Beibu Gulf, six strains were morphologically
characterized using light and scanning electron microscopy, while large subunit rDNA (LSU rDNA)
and internal transcribed spacer (ITS) were sequenced for phylogenetic analysis through maximum
likelihood and Bayesian inferences. Two strains (BGERL169, BGERL170) were identified as Heterocapsa
philippinensis ribotype I, three (BGERL171-BGERL173) as a new Heterocapsa philippinensis ribotype
II, and one strain (BGERL174) as Heterocapsa pseudotriquetra. Cells of H. philippinensis were ovoid
to spherical, yellowish-brown, with reticulate chloroplasts, and had a sausage-shaped nucleus
positioned longitudinally along the dorsal side of the cell, and the theca was arranged in Po, cp, X, 5? ,
3a, 7?? , 6c, 5s, 5??? , 2???? . Additionally, BGERL169 and BGERL171 showed no hemolytic toxicity in rabbit
erythrocyte lysis assays. To the best of our knowledge, this research provides the first morphological
and phylogenetic analysis of H. philippinensis, including the identification of a new ribotype, as well
as the discovery of H. pseudotriquetra in Chinese waters. The findings contribute to the understanding
of Heterocapsa species biogeography and toxicity in Chinese waters, offering valuable data for future
HAB monitoring in Beibu Gulf
Antiviral Effect of Microalgae Phaeodactylum tricornutum Protein Hydrolysates against Dengue Virus Serotype 2
No full textDengue, caused by the dengue virus (DENV), is a global health threat transmitted by Aedes
mosquitoes, resulting in 400 million cases annually. The disease ranges from mild to severe, with
potential progression to hemorrhagic dengue. Current research is focused on natural antivirals due
to challenges in vector control. This study evaluates the antiviral potential of peptides derived from
the microalgae Phaeodactylum tricornutum, known for its bioactive compounds. Microalgae were
cultivated under controlled conditions, followed by protein extraction and hydrolysis to produce
four peptide fractions. These fractions were assessed for cytotoxicity via the MTT assay and antiviral
activity against DENV serotype 2 using flow cytometry and plaque formation assays. The 10?30 kDa
peptide fraction, at 150 and 300 ?g/mL concentrations, demonstrated no cytotoxicity and significantly
reduced the percentage of infected cells and viral titers. These findings suggest that peptides derived from Phaeodactylum tricornutum exhibit promising antiviral activity against dengue virus serotype 2,
potentially contributing to developing new therapeutic approaches for dengue
Land-Use Optimization and Allocation for Saltwater Intrusion Regions: A Case Study in Soc Trang Province, Vietnam
No full textLand-use planning plays an important role in agricultural development. However, the
tools used to support planners in proposing land-use planning solutions are lacking, especially
when considering saltwater intrusion conditions in coastal regions. In this study, optimization is
applied by analyzing land use in developing solutions for agricultural land-use planning, wherein
a multi-objective optimization model is developed to optimize land-use area, including land-use
allocation, and taking into account socioeconomic and environmental factors. The model was applied
to three districts of Soc Trang province, Vietnam (Long Phu, My Xuyen, and Tran De), representing
three ecological regions of salt water, brackish water, and fresh water in the Mekong Delta of
Vietnam. The results are shown for the implementation of two multi-objective optimization scenarios
(in terms of profit, labor, environment benefits, and risk reduction) as follows: (i) multi-objective
optimization of agricultural land use until 2030 under normal conditions; (ii) optimizing agricultural
land use until 2030 under climate change conditions similar to the 2016 drought and saltwater
intrusion phenomenon in the Mekong Delta. The results demonstrate that the second scenario is the
preferred option for implementing land-use planning thanks to the balance between good profits and
minimizing economic and environmental risk. Land allocation was carried out by taking into account
the factors of household economics, the influence of adjacent production types, local traffic, and canal
systems to allocate areas toward ensuring optimal land use. This process, involving a combination of
land-use optimization and spatial allocation, can help planners to improve the quality of agricultural
land-use planning
A Comprehensive Review of Machine Learning for Water Quality Prediction over the Past Five Years
No full textWater quality prediction, a well-established field with broad implications across various
sectors, is thoroughly examined in this comprehensive review. Through an exhaustive analysis of
over 170 studies conducted in the last five years, we focus on the application of machine learning
for predicting water quality. The review begins by presenting the latest methodologies for acquiring
water quality data. Categorizing machine learning-based predictions for water quality into two
primary segments?indicator prediction and water quality index prediction?further distinguishes
between single-indicator and multi-indicator predictions. A meticulous examination of each method?s
technical details follows. This article explores current cutting-edge research trends in machine
learning algorithms, providing a technical perspective on their application in water quality prediction.
It investigates the utilization of algorithms in predicting water quality and concludes by highlighting
significant challenges and future research directions. Emphasis is placed on key areas such as
hydrodynamic water quality coupling, effective data processing and acquisition, and mitigating
model uncertainty. The paper provides a detailed perspective on the present state of application and
the principal characteristics of emerging technologies in water quality prediction
The Effect of Phosphorus Concentration on the Co-Production of Fucoxanthin and Fatty Acids in Conticribra weissflogii
No full textThe production of fucoxanthin and fatty acids in Conticribra weissflogii has been examined,
but the role of elements like phosphorus in their mutualistic interactions is not well understood. To
fill this gap, our study utilized potassium dihydrogen phosphate (KH2PO4) as a source of phosphorus
to examine its impact on the synthesis of fucoxanthin and fatty acids in C. weissflogii. Our findings
revealed that at a phosphorus concentration of 10 mg L?1, the cell density (9.5 ? 105 cells mL?1),
carotenoid concentration (1.67 mg g?1), fucoxanthin concentration (0.91 mg L?1), and fucoxanthin
content (1.33 mg g?1) were maximized. Additionally, at a phosphorus concentration of 20 mg L?1,
cell dry weight (0.76 ? 0.08 g L?1), total fatty acid content, saturated fatty acids, and unsaturated
fatty acids were all at their highest levels, making this concentration optimal for EPA accumulation.
In conclusion, manipulating the phosphorus concentration can enhance the levels of fucoxanthin and
unsaturated fatty acids in C. weissflogii, offering valuable insights into the co-production of these two
high-value compounds within this species
Nine New Antibacterial Diterpenes and Steroids from the South China Sea Soft Coral Lobophytum catalai Tixier-Durivault
No full textFive newcembrane-type diterpenes, lobocalinesA?E (1?5), and four newsteroids, lobocaloids
A?D (9?12), along with six known related compounds (6?8 and 13?15) were isolated from the Yalong
Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated
by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent
density functional theory?electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction
analyses and comparison with the reported spectroscopic data of known compounds. Further, with
the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a.
In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic
bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory
concentration (MIC) values of 8.7 and 17.3 ?g/mL, respectively. All the steroids exhibited antibacterial
activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 ?g/mL.
Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus
aureus, while compounds 8?12 have medium inhibitory effects on the pyocyanin production in
Pseudomonas aeruginosa
ELUSIDASI PROTEIN YANG BERPOTENSI BERKAIT DENGAN JANGKITAN Vibrio parahaemolyticus dalam udang putih, Penaeus vannamei MENGGUNAKAN ANALISIS RANGKAIAN INTERAKSI PROTEIN- PROTEIN PERUMAH-PATOGEN
No full textLEVERAGING AI IN HUMAN RESOURCE MANAGEMENT
Get PDFAutonomic computing investigates how systems can achieve (user) specified ??control?? outcomes
on their own, without the intervention of a human operator. Autonomic computing
fundamentals have been substantially influenced by those of control theory for closed and
open-loop systems. In practice, complex systems may exhibit a number of concurrent and
inter-dependent control loops. Despite research into autonomic models for managing compute
