The Influence of Aerial Exposure on Sea Anemones Aulactinia veratra Mucin Genes Expression Using the RNA Sequencing

Mucin genes are the main component of mucus. The sea anemone species, Aulactinia veratra (Phylum Cnidaria) contains different types of mucin genes. In the intertidal zone, A. veratra is found to be exposed to air during the low tide and produces large quantities of mucus as an external covering. The relation between low tide and mucus secretion is still unclear, and what is the role of mucin during arial exposure is not yet investigated. This study hypothesised that the mucin genes in A. veratra would have significantly high expression in response to aerial exposure. Therefore, the aim of current study was to examine and analyses the response of A. veratra mucins in response to an experiment involving three hours of aerial exposure. To achieve this, aim the RNA-sequencing and bioinformatics analyses were used to examine the expression profile of A. veratra mucin genes in response to aerial exposure. The generated results have shown that, Mucin4-like and mucin5B-like were up-regulated in response to the three hours of aerial exposure in A. veratra. This finding shows a significant role of mucin5B-like and mucin4-like genes in response to air stress at low tide. The data generated from this study could be used in conjunction with future mucin gene studies of sea anemones and other cnidarians to compare A. veratra mucin gene expression results across time, and to extend our understanding of mucin stress response in this phylum.

Characterisation of the Bacteria and Archaea Community Associated with Wild Oysters, At Three Possible Restoration Sites in the North Sea

With 85% of the global oyster reefs destroyed, there is an urgent need for large scale restoration to benefit from the ecosystem services provided by biogenic oyster reefs and their associated biodiversity, including microorganisms that drive marine biogeochemical cycles. This experiment established a baseline for the monitoring of the bacterial and archaeal community associated with wild oysters, using samples from their immediate environment of the Voordelta, with cohabiting Crassostrea gigas and Ostrea edulis, Duikplaats with only C. gigas attached to rocks, and the Dansk Skaldyrcentre, with no onsite oysters. The microbial profiling was carried out through DNA analysis of samples collected from the surfaces of oyster shells and their substrate, the sediment and seawater. Following 16S rRNA amplicon sequencing and bioinformatics, alpha indices implied high species abundance and diversity in sediment but low abundance in seawater. As expected, Proteobacteria, Bacteroidetes, Firmicutes and Thaumarchaeota dominated the top 20 OTUs. In the Voordelta, OTUs related to Colwellia, Shewanella and Psychrobium differentiated the oysters collected from a reef with those attached to rocks. Duikplaats were distinct for sulfur-oxidizers Sulfurimonas and sulfate-reducers from the Sva 0081 sediment group. Archaea were found mainly in sediments and the oyster associated microbiome, with greater abundance at the reef site, consisting mostly of Thaumarchaeota from the family Nitrosopumilaceae. The oyster free site displayed archaea in sediments only, and algal bloom indicator microorganisms from the Rhodobacteraceae, Flavobacteriaceae family and genus [Polaribacter] huanghezhanensis, in addition to the ascidian symbiotic partner, Synechococcus. This study suggests site specific microbiome shifts, influenced by the presence of oysters and the type of substrate.

The Probable Cause for Nesting Pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar Beach, North East Coast of Andaman Island, India

The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with the nesting behaviour of the Olive Ridley turtles. In the present study, characteristics of the breeding beach and nesting pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of Andaman Islands were investigated, during the nesting periods 2016-2017. The study area hosts Olive Ridley, the dominant sea turtles with more than 300 individuals nesting each year. For this study, the number of sea turtles visited, nested, the sediment characters, salinity, and temperature were taken. The exposed sandy nesting beach characteristics are prone to varying degrees of morphological changes every day. The results depict that even though similar grain size (Coarse Sand to Fine Sand and Very well sorted to Poorly Sorted), with an ambient incubating temperature, pH and salinity with wide nesting area, the selective nesting in the particular location of the beach identified because of comfortable energy conditions in the waters (1.5 m/s) favours the female turtles to reach the beach at the preferable site of Ramnagar and nest.

Nesting Biology and Site Selection of Olive Ridley—A Coherence of Nature

Nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. In the present study, characteristics of the breeding turtle, Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of North Andaman Islands were investigated, for the nesting periods 2016-2017. Olive Ridley is the dominant sea turtles, with more than 300 individuals nesting every season with at least a 75% hatching success rate. It is one of the conducive, highly protective and undisturbed nesting sites for Olive Ridley on North Andaman coast. In the present study an initiative is made, to identify nature’s cues and the biological characteristics of Olive Ridley, which leads it to nest at Ramnagar beach, with a high hatchling success rate.

Hydrodynamic Performance of a Newly-Designed Pelagic and Demersal Trawls Using Physical Modeling and Analytical Methods for Cameroonian Industrial Fisheries

This study proposed the newly-designed Pelagic and demersal trawls for the fishing vessels operating in Cameroonian waters in pelagic and demersal fishing grounds. The engineering performances of both trawls were investigated using physical modelling method and analytical method based on the predicted equations. In a flume tank, a series of physical model tests based on Tauti’s law were performed to investigate the hydrodynamic and geometrical performances of both trawls and to assess the applicability of the analytical methods based on predicted equations. The results showed that in model scale, the working towing speed and door spread for the pelagic trawl were 3.5 knots and 1.85 m, respectively, and for the bottom trawl net they were 4.0 knots and 1.8 m. At that speed and door spread, the drag force, net opening height, and wing-end spread of the pelagic model trawl were 36.73 N, 0.89 m, and 0.86 m, respectively, and the swept area was 0.76 m2. Bottom trawl speed and door spread were 30.43 N, 0.38 m, and 0.45 m, respectively, and the swept area was 0.25 m2. The maximum difference between the experimental and analytical results of hydrodynamic performances was less than 56.22% and 41.45%, respectively, for pelagic and bottom trawls, the results of the geometrical performances obtained using predicted equations were close to the experimental results in the flume tank with a maximum relative error less than 12.85%. The newly developed pelagic and bottom trawls had advanced engineering performance for high catch efficiency and selectivity and could be used in commercial fishing operations in Cameroonian waters.

Concentration of Heavy Metals in Sediment and Seagrasses Tissue of the Red Sea Coastal Water of the Sudan

The study investigated the concentration of Lead, Cadmium, Nickels and Chromium in sediment and seagrass tissues at six selected sites along the Sudanese Red Sea coast. The findings of the study added some important and necessary information about the status and condition of the coastal environment in the Sudanese Red Sea coast in terms of the extent of pollution with heavy metals. The study sites included: Marsa Bashayer, Marsa Dama Dama, Green Area, Shipyard, Marsa Halout and Dungonab Bay. The Atomic Absorption Spectrophotometer was used to measure Lead, Cadmium and Nickels. The colorimetric detection method was used for Chromium using the Spectrophotometer. Marsa Dama Dama site revealed high levels concentration of heavy metals in sediment for Lead (60.5) μg/g, Cadmium (0.22) μg/g and Chromium (146.65) μg/g. Marsa Halout showed the highest mean concentration of Nickel in sediment at 14 μg/g. The variation of concentration of metals in sediment between the sites was not significant. The mean concentration of metals in seagrass species tissues ranged from 3.9 to 26.25 μg/g for Lead, 0.1 to 0.90 μg/g for Cadmium, 0.38 to 5.96 μg/g for Nickel and 0.15 to 0.495 μg/g for Chromium. The differences of concentration of heavy metals in seagrass tissues among the sites were significant for Lead and not significant for Cadmium;Nickel and Chromium.

Development and Characterization of 35 SNP Markers in the Fat Greenling Hexagrammos otakii

Hexagrammos otakii is an important kind of economic fish species in East Asia. However, wild H. otakii resources have declined sharply in recent years as a result of human disturbance and habitat destruction. Thus, it is crucial to protect the current resources of H. otakii. In this study, 35 novel single nucleotide polymorphism (SNP) markers were developed based on restriction-site associated DNA sequencing. The results showed that the observed heterozygosity and expected heterozygosity ranged from 0.1875 to 0.6562 and 0.2679 to 0.5079, respectively. The minor allele frequency ranged from 0.1875 to 0.4375. Polymorphic information content ranged from 0.229 to 0.375. Six SNPs were found to be deviated significantly from the HWE (P H. otakii.

Contents and Distribution of Petroleum Hydrocarbons (PHC) in Jiaozhou Bay Waters

Based on data from the investigation in Jiaozhou bay waters in 1979, the distribution, pollution source and seasonal variation of PHC in Jiaozhou Bay are analyzed. It is showed that in Jiaozhou bay PHC contents arrived the national Category Ⅱof the water quality standard during this year. In summer in the bay the pollution of PHC was heavy, while relatively light in spring. In the coastal waters in the east and the northeast of the bay, the PHC contents in spring surpassed the national Category Ⅱ, and surpassed the national Category Ⅲ. In the coastal waters, in the northeast of the bay, the change of the PHC contents formed the grads: the contents presented the falling trend from the big one to the small, which unveiled that the PHC souce in the bay mainly came from the discharge of the industrial waste water and living sewage.

Distribution of Chitinolytic Enzymes in the Organs and cDNA Cloning of Chitinase Isozymes from the Stomach of Two Species of Fish, Chub Mackerel (<i>Scomber japonicus</i>) and Silver Croaker (<i>Pennahia argentata</i>)

Chitinolytic activities were measured in two fish species having different feeding habits, chub mackerel (Scomber japonicus) and silver croaker (Pennahia argentata). Chitinase (an endo-type chitinolytic enzyme) activity was measured using pNP-(GlcNAc)n (n = 2, 3) as substrates;its level was significantly high in the stomachs of both species, as well as in the gills, intestine, pyloric appendage, testis, and liver of chub mackerel and in the spleen, kidney, pyloric appendage, ovaries, heart, and liver of silver croaker. β-N-Acetylhexosaminidase (an exo-type chitinolytic enzyme) activity was measured using pNP-(GlcNAc) as a substrate;it was detected at high levels in many parts apart from the digestive tracts of both species. The optimum pH for chitinase activity was 3.0 - 5.0 in the stomachs of both species, 4.0 in the liver of chub mackerel, and 4.0 and 8.0 in the kidney of silver croaker. Full-length cDNAs encoding two chitinase isozymes were obtained from the stomachs of the two fish species: SjChi-1 (1604 bp) and SjChi-2 (1512 bp) from chub mackerel and PaChi-1 (1630 bp) and PaChi-2 (1606 bp) from silver croaker. Expression analysis of these genes in the organs of the two species revealed strong expression of SjChi-1 in the stomach of chub mackerel and that of PaChi-1 andPaChi-2 in the stomach of silver croaker. The difference in the expression pattern of these genes is likely attributed to the difference in the feeding habits of the two fish species. Our results suggested the presence of novel chitinases in the two species.

Diversity of Secondary Metabolites from Two Antarctic Microbes Rhodococcus sp. NJ-008 and <i>Pseudomonas</i>sp. NJ-011

Diversity analysis on secondary metabolites of Antarctic microbes, Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011, together with the structural elucidation of some purified compounds, has been carried out for understanding of their chemical constituents. The methanol extracts of Rhodococcus sp. NJ-008 and Pseudomonas sp. NJ-011 were subjected to HPLC-TOF MS test for diversity analysis on secondary metabolites, respectively. The chemical constituents of NJ-011 are mainly N-containing compounds including some alkaloids and short polypeptides, while those of NJ-008 are not N-containing ones. Three compounds were also isolated and identified from extract of NJ011 by different column chromatography and preparative HPLC, and their structures were elucidated as b-carboline (1), 3-benzylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (2) and 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione (3) by comparison of TOF MS, 1Hand 13C-NMR data with those reported. More microbial material of Pseudomonas sp. NJ-011 should be needed for exploration of the minor constituents with complicated structures.

Cell Size Dependent Responses of Phytoplankton Assemblages to Nitrate and Phosphate Additions in Surface Waters of the Northern South China Sea

Bioavailability of nitrogen (N) and phosphorus (P) is known to affect marine phytoplankton physiology, thus influencing their primary productivity;and it’s of general interest to see how the N or/and P additions affect the differently cell-sized phytoplankton assemblages. Data from the northern South China Sea showed that P addition increased up to 6 times of total chl a content within 24 h in the estuarine water;and N+P addition increased more than 20 times of chl a within 144 h in the pelagic water. The P addition powered 18.0% and 149% increase in the carbon fixation of larger (>3 μm) and smaller (

Seismic Response of a Typical Fixed Jacket-Type Offshore Platform (SPD1) Under Sea Waves

Offshore platforms in seismically active areas should be designed to service severe earthquake excitations with no global structural failure. In seismic design of offshore platforms, it is often necessary to perform a dynamic analysis that accounts for nonlinear pile soil structures interaction effects. This paper summarizes the nonlinear dynamic analysis of a 3-D model of a typical Jacket-Type platform which is installed in Persian Gulf (SPD1), under simultaneously wave and earthquake loading has been conducted. It is assumed that they act in the same and different directions. The interaction between soil and piles is modeled by equivalent pile length theory. The structure is modeled by finite element method (Ansys Inc.). It be concluded that when the longitudinal components of the earthquake and wave are in different directions, an increase on the response of platform can be seen.

Geochemistry of the Rare Earth Elements (REE) Distribution in Terengganu Coastal Waters: A Study Case from Redang Island Marine Sediment

A study on the rare earth elements (REEs) of Redang Island marine sediments was conducted in August 2011 during the premonsoon season. Bottom sediments were collected from 27 sampling stations on board UMT Discovery II vessel using a Smith McIntyre grab and analyzed for rare earth elements (REEs) using inductively coupled plasma mass spectrometry (ICP-MS). Results showed that the REEs patterns in sediments reflected the source rock patterns with an overall order of abundance such as: light rare earth elements (LREE) > middle rare earth element (MREE) > high rare earth elements (HREE). The chondrite normalized patterns of REEs showed enrichment of LREEs over HREEs with La/Yb of 13.6 while the chondrite normalized value showed low (Gd/Yb)N ratios (2.12) which was illustrated in the flat HREE pattern. The chondrite normalized REE patterns of sediments showed the enrichment of LREE and depletion of HREE. From our findings, REEs concentrations in the study area were found to be of geogenic origins and the distributions were not influenced by anthropogenic sources.

Screening and Phylogenetic Analysis of Deep-Sea Bacteria Capable of Metabolizing Lignin-Derived Aromatic Compounds

Lignin is one of the most abundant biomasses in nature. It is composed of aromatic moieties and has great potential for use in the production of chemical alternatives to petroleum products. Because of increasing interest in biocatalysis, the potential for industrial application of microbial metabolism of lignin-derived compounds has gained considerable recent attention. Functional screenings of culturable bacteria isolated from sediments and sunken wood collected from the deep sea revealed the existence of a number of previously unidentified bacteria capable of metabolizing lignin-related aromatic compounds. Of the 510 isolates obtained in the present study, 208 completely or partially metabolized these compounds. The 208 isolates were classified into diverse phyla, including Firmicutes, Actinobacteria, Bacteroidetes, and Proteobacteria. Among the 208 isolates, 61 unique 16S rRNA gene sequences were detected including previously unidentified marine lineage isolates. The metabolites of the isolates were analysed using liquid chromatography/mass spectrometry (LC/MS) or gas chromatography/mass spectrometry (GC/MS). Most of the representative 61 isolates non-oxidatively decarboxylated the substrates to produce the corresponding aromatic vinyl monomers, which are used as feed stocks for bio-based plastics production. Oxidative metabolism of the lignin-related compounds for assimilation was frequently observed. Our study showed that the deep-sea environment contains an abundance of microorganisms capable of both non-oxidative and oxidative bioconversion of lignin-derived aromatic compounds. The ability for bio-conversion of aromatic compounds found in this study will facilitate the development of future biotechnological applications.

An Effective Extract Method of Phospholipids from Antarctic Krill <em>Euphausea superba</em>

Phospholipids are one of the major bioactive ingredients of Antarctic krill Euphausea superba. A feasible and effective extraction method of Antarctic krill oil was investigated and modified by orthogonal test which the ratio of solid to liquid was 1:2.5, extraction time was 5 min, ratio of ethyl acetate (EA) and n-butanol (BuOH) was 1:1. With this method, the extract of krill oil has a higher phospholipids content of 27.7% - 42.3%, together with total oil yields of 4.15% - 6.18%.

Genetic Variability and Population Structure of Ark Shell in Japan

Ark shell Scapharca kagoshimensis is one of the commercially important bivalve resources in East Asia. In Japan, the mass production method for its natural seedlings was developed in the 1880s, and they had been transplanted to an array of the major fishing areas. It has been therefore concerned with its genetic disturbance among not only current but also former fishing areas in Japan. This study was undertaken to ascertain its genetic diversity and population structure in East Asia by means of nucleotide sequence analysis of a 555-bp portion of the mitochondrial DNA COI gene. Of 225 individuals collected from 8 populations and 1 population in Japan and Korea, respectively, a total of 59 haplotypes, including 14 common haplotypes, were found, and Japan and Korea shared 3 common haplotypes. In Japan, the haplotype diversity and nucleotide diversity ranged from 0.65 to 0.93 and from 0.22% to 0.59%, respectively, reflecting relatively high levels of genetic diversity. The values in Korea were determined to be 0.45% and 0.19%, respectively, indicating significantly lower genetic diversity compared with that in Japan. Mismatch distribution analysis and neutrality tests showed a recent history of multiple types of reproduction and signals of demographic change in each population. These results suggest that S. kagoshimensis has experienced rapid population growth or reduction in population size such as a bottleneck in a short period.

Retrieval of Aerosol Optical Depth from Oceansat-2 OCM

Aerosols are the tiny suspended particles in the atmosphere playing a major role in influencing the net radiation budget of the earth. The aerosols also affect cloud microphysics and those with land origin, possibly reduce the monsoon rainfall. Dynamic and diverse nature of the aerosols varies according to different locations. The aerosols originating due to desert dust, rural atmospheric situations, urban pollutants and marine areas have wide variations and display specific characteristics. Routine monitoring of aerosol events and their subsequent dispersal pattern are important in order to understand their role in climatic process. Hence, it is very important to study the aerosols and their retrieval strategy from the ocean colour remote sensing sensors. The satellite sensors provide platform for making observations covering large area as also their short-term and frequent repetivity. Ocean-colour sensors e.g. CZCS, SeaWiFS, MODIS, POLDAR, Oceansat-1?& 2 OCM have been used to study aerosols, apart from being used to study ocean-colour. Most of the ocean-colour sensors are equipped with a few additional near infrared (NIR) bands (λ?> 700 nm), which are helpful in providing vital information on atmospheric aerosols due to strong absorption by water in NIR wavelengths. The present work is an attempt to study the temporal and spatial variations of Aerosol Optical Depth (AOD) over the Bay of Bengal using Oceansat-2 Ocean Colour Monitor (OCM).

Comparison of the Effect of Tetrapod Block and Armor X block on Reducing Wave Overtopping in Breakwaters

As the Armor shape has a significant effect on the reduction of wave overtopping, this study compares the performance of various shapes of concrete armored blocks of X block and Tetrapod as the most suitable armors. In this study, a three-dimensional numerical model was used for simulation of the effects of waves on the armors of Tetrapod and X Block breakwaters. In this regard, in order to calibrate the numerical model, a sample of conventional stone armor has been selected and using available experimental data on the design of armor such as wave overtopping, wave height, period of waves and energy density of the required spectral range of wave verification was conducted on a numerical model. In this regard, it is necessary to calibrate all the conditions of the model including boundary conditions, numerical modeling, initial conditions, numerical solvers and other parameters in the numerical model and simulation error rate is determined. The maximum error of the numerical model for the relative height values of the impact waves on the structure of breakwater is 7.87% for different conditions. Accordingly, the maximum error of the numerical model in determining overtopping values is 7.81%. The average fluctuation value of overtopping in the X block armor has dropped by about 31% compared to the tetrapod armor.

Molecular Phylogenetic Analysis of Chemosymbiotic Solemyidae and Thyasiridae

In order to invade and adapt to deep-sea environments, shallow-water organisms have to acquire tolerance to high hydrostatic pressure, low water temperature, toxic methane and hydrogen sulfide, and feeding strategies not relying on photosynthetic products. Our previous study showed that the “evolutionary stepping stone hypothe-sis”, which assumes that organic falls can act as stepping-stones to connect shallow sea with deep sea, was supported in Mytilidae. However, it is not known whether other bivalves constituting chemosynthetic communities experienced the same evolutionary process or different processes from mytilid mussels. Therefore, here, we performed phylogenetic analyses by sequencing the nuclear 18S rRNA and mitochondrial COI genes of solemyid and thyasirid bivalves. In Solemyidae, the two genera Solemya and Acharax formed each clade, the latter of which was divided into three subgroups. The Solemya clade and one of the Acharax subgroups diverged in the order of shallow-sea residents, whale-bone residents, and deep-sea vent/seep residents, which supported the “evolutionary stepping stone hypothesis”. Furthermore, in Thyasiridae, the two genera Thyasira and Maorithyas formed a paraphyletic group and the other genera, Adontorhina, Axinopsis, Axinulus, Leptaxinus, and Mendicula, formed a clade. The “evolu-tionary stepping stone hypothesis” was not seemingly supported in the other lineages of Solemyidae and Thyasiridae.

A Process Study of the Tidal Circulation in the Persian Gulf

A homogeneous shallow-water model with free surface is used to model the tidal circulation in the Persian Gulf. The numerical finite-difference model includes harmonic diffusion of horizontal momentum and quadratic bottom friction, it has a 9 km mesh size and it is forced by 7 tidal components at its southern boundary. High precision bathymetric data are used to obtain the bottom topography. The numerical model is run for more than a year. The results are the following: 1) The model accurately reproduces the tidal phase and amplitude observed at 42 tidal gauges in the region. This accuracy is attributed to the presence of the 7 components which are able to interact nonlinearly;2) The amphidromic points are also well positioned by the model due to a proper choice of bathymetry. This was checked also with a simpler geometry of the domain;3) The tidal currents can be strong in the Straits of Hormuz and in shallow areas;thus they will have an effect of the hydrology of the region. The residual currents are weak so that they will be negligible for the large-scale circulation on long periods;4) Finally, the sea-surface elevation forecast by the model is in close agreement with in-situ measurements of pressure in the Straits, performed during the GOGP99 experiment.