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This study identified 260 lanternfish larvae specimens belonging to 20 species from 12 genera, which were obtained from 544 samples of the Ninety East Ridge waters in the Indian Ocean using the COI DNA barcoding. Among the samples, the intra-specific genetic distances ranged from 0% to 2.99%, while inter-specific genetic distances ranged from 1.88% to 25.71%. With the exception of Notolychnus valdiviae, the maximum intra-specific genetic distances were lower than the minimum inter-specific genetic distances for all species. The haplotypes of nine species were analyzed, revealing significant differences in the number, structure, and spatial distribution patterns. Notably, Ceratoscopelus warmingii and Notolychnus valdiviae displayed a significant north-south divergence pattern. The results indicated that seamount topography may influence the gene flow and horizontal distribution patterns of some lanternfish species, as shown by the distribution patterns of different populations of some species.

The application of fast semiautomatic techniques to magnetic data is very useful for data interpretation. A new automatic method is developed to use for 2D magnetic interpretation based on combinat...

Medusae in 116 samples collected from the coastal waters of the northern Beibu Gulf during four seasonal oceanographic cruises from October 2017 to August 2018 were analyzed. In total, 34 species were identified. Two of the species are new to science, Proboscidactyla pentacanalis Xu, Chen & Yang sp. nov. and Helgicirrha apapillata Xu, Chen & Wang sp. nov., and three species are newly recorded in the Beibu Gulf, i.e., Hydractinia vacuolata Xu & Huang, 2006, Proboscidactyla flavicirrata Brandnt, 1834 and Phialella macrogona Xu, Huang & Wang, 1985. Collections of the species were deposited at the Third Institute of Oceanography, Ministry of Natural Resources.

The West Pacific Ocean is considered as the provenance center of global marine life and has the highest species diversity of numerous marine taxa. The phytoplankton, as the primary producer at the base of the food chain, effects on climate change, fish resources as well as the entire ecosystem. However, there are few large-scale surveys covering several currents with different hydrographic characteristics. This study aimed to explore the relationships between the spatio-temporal variation in phytoplankton community structure and different water masses. A total of 630 water samples and 90 net samples of phytoplankton were collected at 45 stations in the Northwest Pacific Ocean (21.0°–42.0°N, 118.0°–156.0°E) during spring and summer 2017. A total of 281 phytoplankton taxa (>5 µm) belonging to 61 genera were identified in the study area. The distribution pattern of the phytoplankton community differed significantly both spatially and temporally. The average abundances of phytoplankton in spring and summer were 797.07×102 cells/L and 84.94×102 cells/L, respectively. Whether in spring or summer, the maximum abundance always appeared in the northern transition region affected by the Oyashio Current, where nutrients were abundant and diatoms dominated the phytoplankton community; whereas the phytoplankton abundance was very low in the oligotrophic Kuroshio region, and the proportion of dinoflagellates in total abundance increased significantly. The horizontal distribution of phytoplankton abundance increased from low to high latitudes, which was consistent with the trend of nutrient distributions, but contrary to that of water temperature and salinity. In the northern area affected by the Oyashio Current, the phytoplankton abundance was mainly concentrated in the upper 30 m of water column, while the maximum abundance often occurred at depths of 50–75 m in the south-central area affected by the Kuroshio Current. Pearson correlation and redundancy analysis (RDA) showed that phytoplankton abundance was significant negatively correlated with temperature and salinity, but positively correlated with nutrient concentration. The phytoplankton community structure was mainly determined by nutrient availability, especially the N:P ratio.

During the last several decades, since the discovery of a decagonal quasicrystal, a 2 nm cluster model has been widely accepted as its basic quasi-unit-cell (QUC). Instead of the traditional 2 nm QUC, a 3.2 nm QUC is proposed in this paper. The 3.2 nm QUC can fill all the blank areas. The 3.2 nm QUC consists of 251 atoms. The element type and position of each atom are determined using high-angle annular detector dark-field (HAADF) images taken along three projection directions, i.e., one along the ten-fold symmetry and the other two along the two-fold symmetry with an intersection angle of 18 degrees. The proposed model opens an avenue for further investigation of the aperiodic atomic structure of other quasicrystals.

In this paper, we present a new method based on the reciprocal of the analytic signal amplitude and its derivatives, to directly estimate the structural indices and location parameters of 2...

We report on the microstructure evolution of yttria-stablized zirconia (YSZ) corroded by molten deposits of Ca10Mg7Al13Si70 (CMAS). The CMAS corrosion induces significant zirconium silicate (ZrSiO4) growth across the entire YSZ coating and causes dramatic microstructure changes marked by the complete disappearance of the feather-like structure of the columnar grains in the upper region of the coating and disintegration of the parent columnar grains into an equiaxed grains near the YSZ/Al2O3 interface. CMAS infiltration along the intercolumnar gaps results in ZrSiO4 growth into YSZ grains. Curvature-driven infiltration of the molten CMAS along ZrSiO4/YSZ interfaces gives rise to dendritic-like ZrSiO4 growth.

The microstructural features of high-temperature sintered and CaO-MgO-Al2O3-SiO2 (CMAS) corroded air plasma sprayed Y2O3 stabilized ZrO2 (YSZ) thermal barrier coatings (TBCs) under the thermal gradient condition were comparatively studied. As-sprayed YSZ has a lamellar structure and the lamellae are composed of closely aligned columnar crystals. The sintered and the CMAS corroded YSZ coatings maintain the t’-ZrO2 phase as the as-sprayed YSZ coating. The sintered YSZ remains the lamellar structure with reduced interlamellar gaps and grains coarsening. After the CMAS corrosion, the top layer of the YSZ coating keeps its lamellar structure consisting of some columnar grains with the CMAS infiltration into the intergrain gaps and the formation of striped Zr2Y2O7. The typical lamellar structure transforms into more equiaxed grains in the middle and bottom layers of the ceramic coating along with significant infiltration of amorphous CMAS and anorthite formation in the bottom layer owing to the high contents of Ca and Al.

Quasicrystals have special crystal structures with long-range order, but without translational symmetry. Unexpectedly, carousel-like successive flippings of groups of atoms inside the ∼2 nm decagonal structural subunits of the decagonal quasicrystal Al

Quasicrystals have special crystal structures with long-range order, but without translational symmetry. Unexpectedly, carousel-like successive flippings of groups of atoms inside the ∼2 nm decagonal structural subunits of the decagonal quasicrystal Al60Cr20Fe10Si10 were directly observed using in situ high-temperature high-resolution transmission electron microscopy imaging. The observed directionally successive phason flips occur mainly clockwise and occasionally anticlockwise. The origin of these directional phason flips is analyzed and discussed.

To investigate the correlation between preoperative inflammatory markers, Ki-67 expression and the pathological grade of glioma, and to provide a reference for clinical prediction of glioma prognosis. A total of 45 glioma patients who underwent surgery with complete clinical and pathological data were in our hospital from January 2012 to December 2018 were enrolled. Glioma was divided into WHO grade I to IV. Forty-five healthy health examiners with matched clinical characteristics were included to the control group. Blood routine tests were recorded at admission in both the glioma and control group. The ratio of neutrophil to lymphocyte cytometry (NLR), derived neutrophil to lymphocyte ratio (dNLR) (white blood cell count – neutrophil count to neutrophil count), platelet to lymphocyte ratio (PLR) and prognostic nutritional index (PNI, serum albumin content + 5 × lymphocyte count) were calculated. The expression of Ki-67 in glioma was detected by immunohistochemistry. The relationship between the above markers, Ki-67 expression and pathological grade of glioma was evaluated with receiver operating characteristics curve analysis and Spearman correlation test. The correlation between the markers and Ki-67 were also determined. NLR, dNLR, PLR were increased in the glioma group (P

Fish species composition and spatio-temporal variability of the community were studied in a tropical seagrass meadow located in a lagoon in the eastern part of North Sulawesi. The diversity of fish community in the seagrass meadows was relatively high, with the Shannon-Wiener index ranging from 1.57 to 3.69. The family Apogonidae was the most dominant in abundance (8.27 ind./(100 m2)) and biomass (28.49 g/(100 m2)). At the species level, Apogon lateralis and Sphaeramia orbicularis were the most dominant species in abundance and biomass, respectively. For spatial distribution on species, the end, middle and mouth of the lagoon clustered together as a whole, which may be due to the substrate types found in those zones. The fish species, fish abundance and fish biomass were greater in the dry and wet seasons than in the transition season, which is explained by the strong monsoon, which provides a more suitable environment and food for the fish. The maximum length of 93.10% of the captured species was less than their length at maturity, indicating that seagrass meadows are nursery habitats for many fishes. Therefore, protection of the seagrass meadows is essential for fisheries and sustainable resource utilization.

Based on oceanographic survey data in June 2012 in the Lembeh Strait, the zooplankton ecological characteristics such as species composition, individual abundance, dominant species and distribution were analyzed. The results showed that 183 species (including 4 sp.) had been recognized, most of them belonged to copepoda. Cnidaria followed with 43 species (including 1 sp.) were identified. The average abundance of zooplankton was (150.47±58.91) ind./m3. As to the horizontal distribution, the abundance of the zooplankton was higher in the southern waters than in the northern waters. The dominant species in the study area were Lensia subtiloides, Sagitta enflata, Lucifer intermedius, Oikopleura rufescens, Diphyes chamissoni, Creseis acicula, Subeucalanus subcrassus, Temora discaudata, Aglaura hemistoma, Doliolum denticulatum, Canthocalanus pauper, Oikopleura longicauda and Nanomia bijuga. Zooplankton biodiversity indexes were higher in study area than previous study in the other regions. The findings from this study provide important baseline information for future research and monitoring programs.

The community structure of zooplankton has been conducted in the Lembeh Strait in Bitung and Wori Beach in Manado, North Sulawesi in October 2015. Sampling of this research was conducted in 22 sampling sites along the strait. Zooplankton samples were collected from 22 stations, by NORPAC 300 μm net that was vertically hauled from maximum 10 m depth up to the surface water. The samples were poured into the bottle with formalin of 4% as preservative. The results showed that there were 43 taxa of zooplankton. The abundance of zooplankton was between 21.216–4 193.776 ind./m3. The dominant taxa were copepod, especially Calanoida. The composition of zooplankton was relatively similar in all stations. We showed the abundance, dominance, composition and distribution of zooplankton at this research. More extensive studies concerning zooplankton is required to understand zooplankton biodiversity as a whole especially on the geographical and spatial distribution to describe population and community dynamic in the Lembeh Strait and Wori Beach.

The structural aspects of yttria-stabilized zirconia (YSZ) thermal barrier coatings grown on a polycrystalline alumina substrate have been studied as a function of annealing time at 1250 °C with the use of electron microscopy, X-ray diffraction, and Raman spectroscopy. Upon the high temperature exposure, the feathery morphology of the columnar grains of the as-deposited coatings smoothens out with the concurrent development of surface undulations and grain coarsening. It is shown that the grain coarsening results in significant voiding along the merged grain boundaries and inside YSZ grains. The nucleation and growth of the high density of voids is related to the clustering of vacancies supplied from the merged gaps between columnar grains and subgrains within the columnar grains. The continued development of the voids leads to the formation and propagation of large cracks within the columnar grains, which weakens the overall mechanical integrity of the coating.

The interface oxidation induced microstructural evolution of air plasma spayed (APS) thermal barrier coatings (TBCs) is investigated. As the oxidation progresses, the thermally grown oxide (TGO) formed at the YSZ/NiCrAlY interface develops from a bi-layered structure, to a three-layered structure, then to a four-layered structure of Al2O3, Y3Al5O12 (YAG), NiCr2O4 and NiO, respectively. An oxidation mechanism is proposed to account for the growth of the layered TGO. The YAG formation consumes the underlying alumina layer and facilitates the outward diffusion of Cr and Ni, leading to a detrimental effect on the TBC life.

We developed a multilayer structure shear lag model used in analyzing tensile fracture behavior of supersonic plasma sprayed 8 wt% yttria-stabilized zirconia thermal barrier coatings (TBCs). The closed-form solutions of plane and shear stresses were deduced by using the shear lag model. Dynamic strain fields, cracking nucleation and propagation features of TBCs during tensions were in-situ monitored by non-contact digital image correlation (DIC) measurement system. The evolutions of plane and shear stresses in TBCs were estimated by the above closed-form solutions. Using in-situ measurement results of DIC, we further obtained the fracture strengths, interface shear strengths, fracture energy and fracture toughness of TBCs, and summarized the whole tensile fracture mechanisms of TBCs. This shear lag model with the aid of DIC is useful for measuring the mechanical properties of other novel multiple-layer structure brittle coating/ductile substrate systems.

In this paper, scanning transmission electron microscopy is used to study the microstructures of the defects in LaCoO3/SrRuO3 multilayer films grown on the SrTiO3 substrates, and these films have different thickness of SrRuO3 (SRO) layers. Several types of Ruddlesden-Popper (R.P.) faults at an atomic level are found, and these chemical composition fluctuations in the growth process are induced by strain fields originating from the film-film and film-substrate lattice mismatches. Furthermore, we propose four types of structural models based on the atomic arrangements of the R.P. planar faults, which severely affect the functional properties of the films.

Global warming has caused Arctic sea ice to rapidly retreat, which is affecting phytoplankton, the primary producers at the base of the food chain, as well as the entire ecosystem. However, few studies with large spatial scales related to the Arctic Basin at high latitude have been conducted. This study aimed to investigate the relationship between changes in phytoplankton community structure and ice conditions. Fifty surface and 41 vertically stratified water samples from the western Arctic Ocean (67.0°–88°26′N, 152°–178°54′W) were collected by the Chinese icebreaker R/V Xuelong from July 20 to August 30, 2010 during China’s fourth Arctic expedition. Using these samples, the species composition, spatial distribution, and regional disparities of phytoplankton during different stages of ice melt were assessed. A total of 157 phytoplankton taxa (>5 μm) belonging to 69 genera were identified in the study area. The most abundant species were Navicula pelagica and Thalassiosira nordenskioeldii, accounting for 31.23% and 14.12% of the total phytoplankton abundance, respectively. The average abundance during the departure trip and the return trip were 797.07×102 cells/L and 84.94×102 cells/L, respectively. The highest abundance was observed at Sta. R09 in the north of Herald Shoal, where Navicula pelagica was the dominant species accounting for 59.42% of the abundance. The vertical distribution of phytoplankton abundance displayed regional differences, and the maximum abundances were confined to the lower layers of the euphotic zone near the layers of the halocline, thermocline, and nutricline. The species abundance of phytoplankton decreased from the low-latitude shelf to the high-latitude basin on both the departure and return trips. The phytoplankton community structure in the shallow continental shelf changed markedly during different stages of ice melt, and there was shift in dominant species from centric to pennate diatoms. Results of canonical correspondence analysis (CCA) showed that there were two distinct communities of phytoplankton in the western Arctic Ocean, and water temperature, ice coverage and silicate concentration were the most important environmental factors affecting phytoplankton distribution in the surveyed sea. These findings will help predict the responses of phytoplankton to the rapid melting of Arctic sea ice.

Double perovskite generally exhibits small structure distortion induced by the expansion/contraction and tilting of the BO6 octahedron. It is difficult to precisely determine their structures, particularly the phase with notable pseudo-symmetry structure and two or more phases with slightly different structures. In this paper, the double perovskite Y2CrMnO6 synthesized under high pressure was studied using scanning transmission electron microscopy and first-principles calculations. The new finding is that a rock-salt ordered structure and a layer ordered structure coexist in Y2CrMnO6. Similar to the Cu2+-based compound, this Mn3+-based compound is another new system with layer ordered structure. Unlike the structures of YCrO3 and YMnO3, the ordered structure of Y2CrMnO6 displays half-metal characteristics.

Manganese bromide has attracted enormous attention for its applications in the syntheses of organic-inorganic hybrid compounds. A complete understanding of structural and chemical stabilities of MnBr 2 is important for controlling its properties. Here, we focus on the irradiation resistance of MnBr 2 . The chief purpose of this research is reached by in situ transmission electron microscopy. It is demonstrated that the deliquescent MnBr 2 powder is prone to adsorb the vapor in air, and the hydrous MnBr 2 can be decomposed under its continuous exposure to electron beam, indicated by a transmission electron microscope via the catalysis of Cu grid at room temperature.

Inverse [Formula: see text] filtering can perform energy compensation and phase correction of seismic reflection data, but it has an instability problem due to its high-pass characteristics. Although improved methods, such as gain-limited inverse [Formula: see text] filtering and stabilized inverse [Formula: see text] filtering, overcome the instability to some extent, they are not suitable for compensating deep seismic reflection events with weak energy. Focusing on the enhancement of deep seismic events, we have developed a balanced filtering method based on the ratio of the phase-compensated signal to its analytic signal counterpart. The method is insensitive to the depth of seismic records, and it can make shallow and deep seismic records visible simultaneously. When tested on synthetic data and real seismic data, compared with other methods, the balanced filtering method improves the amplitude strength of the deep reflection events and the continuity of shallow and deep seismic events effectively, which makes the deep reflection data easier to interpret.

Ca50Mg10Al10Si30 (CMAS) corrosion induced microstructure evolution and composition development in yttria-stabilized zirconia (YSZ) thermal barrier coatings prepared by electron-beam physical vapor deposition (EB-PVD), have been investigated by means of analytical electron microcopy, Raman spectroscopy and X-ray diffraction. The corroded YSZ still mainly consists of t-ZrO2 and no harmful monoclinic zirconia formation occurs; however, the feathery and columnar morphology of the as-deposited YSZ coating transforms into an equiaxed grain structure with dramatic grain coarsening and significant CMAS infiltration. The CMAS corrosion induces dissolution of YSZ into the molten CMAS, spinel MgAl2O4 formation both in the intergranular gaps and inside YSZ grains, and anorthite (CaAl2Si2O8) precipitates in the intergranular gaps with reduced Mg and Ca content in the infiltrated amorphous CMAS. These results show that CMAS with a high content of calcium can induce significant grain coarsening and microstructure evolution that has a detrimental effect on primary function of the YSZ coating.

To characterize the metallogenic environment of a typical vein-type uranium deposit, samples from diabase dykes, alteration zones including metamorphic diabase and uranium ore, and granites were systematically investigated for six boreholes from southeastern China. Rock magnetic results indicate that coarse-grained magnetites (pseudosingle domain, PSD, and multidomain, MD) are dominant magnetic carriers in diabase. In contrast, the uranium ore is dominated by fine-grained magnetites (superparamagnetic, SP, and single-domain, SD). The concentration of magnetic particles in fresh granites is low. Magnetic properties of metamorphic diabases exhibit much greater variability of magnetic properties and higher degrees of sulfuration than unaltered diabase and granite, due to contact metasomatism and reduction effects close to the vein. Compared with diabase, magnetic remanence of the uranium ore is much lower, but displays much higher stability. The Koenigsberger ratio Q peaks in the uranium ore with a value of ∼1.00. Using the systematic rock magnetic results to constrain the interpretation, the contribution of the intersection zone of diabase dyke and silicified fault to magnetic anomalies was further modeled, and the effects of the ore body are significant for magnetic exploration. Overall, rock magnetic investigations of vein-type uranium deposit provide a better understanding of the interactions between different rock types, and further facilitate regional magnetic surveys on the ground.