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With the expanding size of 3D seismic data, manual seismic interpretation becomes time-consuming and labor-intensive. For automating this process, recent progress in machine learning, in particular the convolutional neural network (CNN), has been introduced into the seismic community and successfully implemented for interpreting seismic structural and stratigraphic features. In principle, such automation aims at mimicking the intelligence of experienced seismic interpreters to annotate subsurface geology accurately and efficiently. However, most of the implementations and applications are relatively simple in their CNN architectures, which primary rely on the seismic amplitude but undesirably fail to fully use the preknown geologic knowledge and/or solid interpretational rules of an experienced interpreter who works on the same task. We have developed a generally applicable framework for integrating a seismic interpretation CNN with such commonly used knowledge and rules as constraints. Three example use cases, including relative geologic time-guided facies analysis, layer-customized fault detection, and fault-oriented stratigraphy mapping, are provided for illustrating how one or more constraints can be technically imposed and demonstrating what added values such a constrained CNN can bring. It is concluded that the imposition of interpretational constraints is capable of improving CNN-assisted seismic interpretation and better assisting the tasks of subsurface mapping and modeling.

A Gymnodinium-like dinoflagellate, Kirithra sigma sp. nov., was isolated from Jiaozhou Bay, China, and the southern coast of Korea, and examined by light, scanning, and transmission electron micros...

Although the life cycle of Margalefidinium polykrikoides, formerly called Cochlodinium polykrikoides, has been described previously, the descriptions on asexual and sexual phases of this species collected from Korean coastal waters are strange and still unclear. We collected the resting cysts of M. polykrikoides from surface sediments and re-examined the germination process, and asexual and sexual life stages, and the mating behavior of the vegetative cells using a microscope equipped with high-resolution time-lapse digital camera. The resting cyst of M. polykrikoides had a distinct germination process; before germination, a mature cell in shape was visible within the resting cyst body, and the cell quickly emerged from the resting cyst. The asexual reproduction and cell chain formation of M. polykrikoides were generated in a slightly oblique direction at the epicone of cell and the chain-forming cells of M. polykrikoides could form the chain-forming temporary cysts without asexual or sexual reproduction. The planozygote produced by gamete fusion of M. polykrikoides may not necessarily develop to resting cysts but instead may divide into vegetative cells occasionally. In this phase, the armored cell, which was previously recorded by Kim et al. (2007), was not observed. The sexuality of M. polykrikoides had a homothallic mating behavior.

Depicting geologic sequences from 3D seismic surveying is of significant value to subsurface reservoir exploration, but it is usually time- and labor-intensive for manual interpretation by experienced seismic interpreters. We have developed a semisupervised workflow for efficient seismic stratigraphy interpretation by using the state-of-the-art deep convolutional neural networks (CNNs). Specifically, the workflow consists of two components: (1) seismic feature self-learning (SFSL) and (2) stratigraphy model building (SMB), each of which is formulated as a deep CNN. Whereas the SMB is supervised by knowledge from domain experts and the associated CNN uses a similar network architecture typically used in image segmentation, the SFSL is designed as an unsupervised process and thus can be performed backstage while an expert prepares the training labels for the SMB CNN. Compared with conventional approaches, the our workflow is superior in two aspects. First, the SMB CNN, initialized by the SFSL CNN, successfully inherits the prior knowledge of the seismic features in the target seismic data. Therefore, it becomes feasible for completing the supervised training of the SMB CNN more efficiently using only a small amount of training data, for example, less than 0.1% of the available seismic data as demonstrated in this paper. Second, for the convenience of seismic experts in translating their domain knowledge into training labels, our workflow is designed to be applicable to three scenarios, trace-wise, paintbrushing, and full-sectional annotation. The performance of the new workflow is well-verified through application to three real seismic data sets. We conclude that the new workflow is not only capable of providing robust stratigraphy interpretation for a given seismic volume, but it also holds great potential for other problems in seismic data analysis.

Gonyaulax verior was initially described as Amylax diacantha from Belgian coastal waters a century ago but its detailed morphology needed restudy. Here, we established nine strains of G. verior by germinating cysts or isolating cells from localities from the European Atlantic to the Caspian Sea and the Pacific Ocean. Both cyst and thecal morphology were examined by light and scanning electron microscopy. SSU, LSU and/or ITS-5.8S rRNA gene sequences were obtained from all strains. Cells of G. verior have a plate formula of Po, 4′, 2a, 6-7′′, 6C, 6S, 6′′′, 1p, 1′′′′ with an L-type ventral organisation, characterised by two either straight or curved antapical horns of variable length. Cysts of G. verior are oval, smooth and contain one or two yellow accumulation bodies. The maximum-likelihood and Bayesian inference analyses based on SSU and LSU rRNA gene sequences revealed two clades of G. verior, referred to as ribotypes A and B. Genetic distances based on ITS-5.8S rRNA gene sequences within the same ribotype were less than 0.06, but greater than 0.32 between ribotypes. G. verior is reclassified as Sourniaea diacantha gen. et comb. nov., which is attributed to Lingulodiniaceae together with Pyxidinopsis, Lingulodinium and Amylax. Our results suggest that Lingulodiniaceae can be separated from Protoceratiaceae and Gonyaulacaceae based on ventral organisation, apical complex, ventral pore and number of anterior intercalary plates. One strain of S. diacantha was examined for yessotoxin production by LC-MS/MS but did not produce toxin.

Metallic glasses (MGs) have attracted great attention in wastewater treatment because of their high reactivity arising from amorphous structure, large residual stress and high density of low coordination sites. However, the reactivity of MGs would gradually slow down with time due to the passivation of active sites by corrosion products, resulting in limited long-term reactivity, which is also an unsolved key issue for established crystalline zero valent iron (ZVI) technology. Here, such problems are successfully overcome by introducing nanoscale chemical inhomogeneities in Fe-based MG (Fe-MGI), which apparently contributes to local galvanic cell effect and accelerates electron transfer during degradation process. More importantly, the selective depletion of Fe0 causes local volume shrinkage and crack formation, leading to self-peeling of precipitated corrosion products and reacted regions. Thereby fresh low coordination sites could be continuously provided, counteracting the mass transport and reactivity deteriorating problem. Consequently, Fe-MGI demonstrates excellent long-term reactivity and self-refreshing properties even in neutral solution. The present results provide not only a new candidate but also a new route of designing ZVI materials for wastewater treatment.

An aerobic, Gram-stain-negative, weak-motile, short-rod-shaped bacterial strain, designated JBR3-12T, was isolated from halophyte Carex pumila plants, and its taxonomic position was investigated by using a polyphasic taxonomic approach. The strain produced a pink pigment on tryptic soy agar and grew optimally at 25 °C, pH 8 and in the presence of 3 % (w/v) NaCl. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain JBR3-12T formed a lineage within the genus Pedobacter and was most closely related to Pedobacter sandarakinus DS-27T (98.0 %) and Pedobacter agri PB92T (97.6 %). The DNA G+C content of the genome was 41.3 mol%; the whole genome length was 5 426 070 bp. The major fatty acids of JBR3-12T were iso-C15 : 0, summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c) and iso-C17 : 0 3-OH. The predominant polar lipid was phosphatidylethanolamine. The predominant quinone was menaquinone-7. Based on its phenotypic, phylogenetic and genotypic features, strain JBR3-12T is proposed to represent a novel species of the genus Pedobacter , for which the name is Pedobacter endophyticus sp. nov. The type strain is JBR3-12T (=KCTC 82363T=NBRC 114901T).

There have been controversies regarding the taxonomy of Prorocentrum donghaiense, however Zhang et al. (2016) recently developed a probe with a quantitative real-time PCR (qPCR) assay that targets the D1–D2 region of the large subunit (LSU) rDNA of this species. We used this qPCR assay to determine the spatial distribution and abundance of P. donghaiense along the East China Sea (ECS) and Korean coastal area. During 15–22 May 2017, surface water samples were collected to extract genomic DNA and subsequent qPCR at 29 stations of the ECS and Korean coastal area, and the water temperature and salinity were also recorded at the time of sampling. The morphological features of P. donghaiense collected from the study area were identical to those of P. shikokuense and P. donghaiense reported in previous studies. Higher cell densities were recorded at water temperatures of 14.8 to 19.3°C and at salinity of 32.3 to 34.0, indicating that P. donghaiense can grow in a broad range of water temperatures. In addition, relatively higher cell densities were generally observed within stations that are affected by the Changjiang Diluted Water and Taiwan Warm Current flows, and low cell densities were prominent near the Japanese coast that is affected by the Tsushima Current flow and in the southwest coast of Korea. These results suggest that P. donghaiense occurs throughout a broad area of the ECS and Korean coastal area, and the current flows in the ECS may stimulate P. donghaiense blooms.

We describe the life cycle, morphology and molecular phylogenetic position of Fragilidium mexicanum, based on vegetative cells established by incubation of resting cysts isolated from sedim...

To facilitate the utilization of large-scale unlabeled data, we propose a simple and effective method for semi-supervised deep learning that improves upon the performance of the deep learning model. First, we train a classifier and use its outputs on unlabeled data as pseudo-labels. Then, we pre-train the deep learning model with the pseudo-labeled data and fine-tune it with the labeled data. The repetition of pseudo-labeling, pre-training, and fine-tuning is called naive semi-supervised deep learning. We apply this method to the MNIST, CIFAR-10, and IMDB data sets, which are each divided into a small labeled data set and a large unlabeled data set by us. Our method achieves significant performance improvements compared to the deep learning model without pre-training. We further analyze the factors that affect our method to provide a better understanding of how to utilize naive semi-supervised deep learning in practical application.

Carbonate-type Mg–Al layered double hydroxides were successfully prepared using ion exchange resins. Based on XRD patterns, 8 h and 40°C were considered to be an optimal reactive condition to obtain pure Mg6Al2(OH)16CO3 · 4H2O. SEM showed a sheet structure of samples, the largest diameter and the mean thickness were roughly 2 µm and 100 nm, respectively. EDS datas indicated that temperature was one of key influence factors to obtain the excellent composite materials. FT-IR and TG-DSC results further confirmed that the proposed method was feasible and effective to prepare carbonate-type Mg–Al layered double hydroxides.

Acid propped fracturing is one of the most effective methods to enhance the stimulation effect, especially in the high-temperature deep carbonate formation. However, the short-term conductivity experimental data used in existing acid fracturing optimal designs may not be directly applicable to the real case. Aiming at this problem, this paper conducted a research on long-term acid conductivity behavior and proposed a new method to raise acid fracture conductivity under high closure stress. Frist, a series of experiments with carbonate core samples were conducted to investigate long-term acid conductivity behavior of carbonate reservoirs with closure stress up to 100 MPa. Gelled and cross-linked acids with different acid-rock contact times were tested to analyze the effects of acid type and acid-rock contact time on the conductivity. Next, acid fracture conductivity by adding proppant was tested to investigate the feasibility of increasing acid fracture conductivity under high closure stress. Long-term conductivity was measured up to 168 h to analyze the impact of deformation and embedment of proppant on conductivity. Finally, proppant size and concentration on conductivity were optimized for maximizing conductivity. The study shows that the conductivity with gelled acid is higher than the case with cross-linked acid for the same contact time. When the contact time is 60 min, gelled acid fracture conductivity has already reached its upper limit. The ideal combination of proppant size and concentration are optimized at different stress level. When the closure pressure is below 50 MPa, the conductivity is the highest at the proppant concentration of 0.75 kg/m2 using 20/40 mesh proppant. While the closure pressure exceeds 50 MPa, the conductivity is the highest at the proppant concentration of 3 kg/m2 using 40/70 mesh proppant. The acid propped fracture conductivity decreases rapidly in 48 h and undergoes the gradual drop, remaining steady after 120 h. An analytical model of acid propped fracture conductivity was also developed. This study provided an insight into optimizing acid propped fracturing design and predicting well performance.

To investigate dinoflagellate cyst production and seasonality in relation to major environmental factors, such as water temperature, salinity, chlorophyll-a (chl-a) and dissolved nutrients, and to propose dinoflagellate cysts as possible biological indicators for the reconstruction of past environmental conditions, a sediment trap study was conducted for one year, from March 2011 to February 2012, in Jinhae-Masan Bay, Korea. Marked increases in dinoflagellate cyst production were documented in Jinhae-Masna Bay during two distinct seasons (summer and late autumn) characterized by different environmental conditions. Summer (July and August) was characterized by relatively high water temperature, dissolved inorganic nitrogen (DIN), and chl-a concentrations and low salinity, whereas late autumn (November and December) exhibited high dissolved inorganic phosphorus, low water temperature and high salinity, compared to those of the summer. Fourteen dinoflagellate cyst taxa were identified. These assemblages were dominated by Brigantedinium species (round brown cyst), cysts of Scrippsiella species, Spiniferites species and cysts of Alexandrium species (ellipsoidal cyst). The total flux of dinoflagellate cysts ranged from 781 cysts m −2 day −1 to 5602 cysts m −2 day −1, and the production of autotrophic dinoflagellate cysts was mainly restricted to the warmest months (July–September) and autumn. Multivariable analysis revealed that the production of major dinoflagellate cysts, excluding those of Brigantedinium species, can be enhanced by environmental conditions during summer in Jinhae-Masan Bay. In particular, the increased production of cysts of Scrippsiella species was related to increased water temperature, and the increased production of Spiniferites species was associated with lower salinity. Two peaks in cyst production of Alexandrium species in August and November corresponded with significant increases in DIN and DIP; however, no significant relationship was found between the production of Brigantedinium species and environmental factors in Jinhae-Masan Bay. These results suggest that the cysts of Scrippsiella species, Spiniferites species and cysts of Alexandrium species present in sediment samples from Jinhae-Masan Bay can be used as biological indicators to reconstruct past environmental conditions involving relatively high water temperature, low salinity and enhanced nutrient level.

The dinoflagellate genus Scrippsiella is a common member of phytoplankton and their cysts are also frequently reported in coastal sediments worldwide. However, the diversity of Scrippsiella in Korean waters has not been fully investigated. Here, several isolates of Scrippsiella precaria collected from Korean waters and germinated from resting cysts were examined using light and scanning electron microscopy. The resting cysts were characterized by pointed calcareous spines and one or two red accumulation bodies, and the archeopyle was mesoepicystal, representing the loss of 2–4′ and 1–3a paraplates. Rounded resting cysts were found in culture, and an increase in spine length was observed until 8 days of development. Korean isolates of S. precaria had the plate formula of Po, X, 4′, 3a, 7″, 6C, 4S, 5‴, 2⁗. There were differences in the cell size and location of the red body between Korean isolates and previously described cells of S. precaria. In addition, the Korean isolates of S. precaria had two types of the 5″ plate that either contacted the 2a plate or not. Molecular phylogeny based on internal transcribed spacer (ITS) and large subunit (LSU) rDNA sequences revealed that the Korean isolates were nested within the subclade of PRE (S. precaria and related species) in the clade of Scrippsiella sensu lato, and that the PRE subclade had two ribotypes: ribotype 1 consisting of the isolates from Korea, China, and Australia, and ribotype 2 consisting of the isolates from Italy and Greece. Lineages between isolates of ribotype 1 were likely to be related to the dispersal by ocean currents and ballast waters from international shipping, and the two types of spine shapes and locations of the 5″ plates may be a distinct feature for ribotype 1.

Liquid unloading is a very common and important issue in horizontal gas wells, and the presence of curve sections increases the complexity of the phenomenon and its study. Liquid loading in a gas well will sharply reduce production, therefore, the liquid-unloading onset of different curved pipes is essential to gas production. In this work, liquid-unloading onset experiments were conducted in curved pipes with different curvatures. Then, the critical gas velocityVsgCRcan be determined according to the measured pressure gradients, liquid holdup, and liquid film reversal. This work analyzes the factors which will lead to the liquid unloading and explores the trend of the pipe curvature’s influence on the liquid unloading under laboratory conditions. The experimental results show that the critical gas velocity rises with the increase of pipe curvature, the increase is mainly due to the centrifugal force. The present work also compares the predicted results of the OLGA model and Beggs–Brill model with experimental data. The comparison results indicate that both models fit relatively well to the experimental data at the low superficial gas velocity, and both models have poor performance at high superficial gas velocity. The OLGA model fits the experimental data better than the Beggs–Brill model at high superficial gas velocity. The error analysis shows that most of the predicted data is not in good agreement with experimental data. Some errors between experimental data and calculation results are out of the range of 50%.

8 pages, 2 tables, A recently published study analyzed the phylogenetic relationship between the genera Centrodinium and Alexandrium, confirming an earlier publication showing the genus Alexandrium as paraphyletic. This most recent manuscript retained the genus Alexandrium, introduced a new genus Episemicolon, resurrected two genera, Gessnerium and Protogonyaulax, and stated that: “The polyphyly [sic] of Alexandrium is solved with the split into four genera”. However, these reintroduced taxa were not based on monophyletic groups. Therefore this work, if accepted, would result in replacing a single paraphyletic taxon with several non-monophyletic ones. The morphological data presented for genus characterization also do not convincingly support taxa delimitations. The combination of weak molecular phylogenetics and the lack of diagnostic traits (i.e., autapomorphies) render the applicability of the concept of limited use. The proposal to split the genus Alexandrium on the basis of our current knowledge is rejected herein. The aim here is not to present an alternative analysis and revision, but to maintain Alexandrium. A better constructed and more phylogenetically accurate revision can and should wait until more complete evidence becomes available and there is a strong reason to revise the genus Alexandrium. The reasons are explained in detail by a review of the available molecular and morphological data for species of the genera Alexandrium and Centrodinium. In addition, cyst morphology and chemotaxonomy are discussed, and the need for integrative taxonomy is highlighted, Support to DMA from the NOAA ECOHAB program (Grant #NA15NOS4780181) is gratefully acknowledged. Support to EG, AR, NS from the COPAs project (CTM2017-86121-R) is acknowledged. IGL and CJBS are COFFA-IPN and EDI-IPN fellows, With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

Dinoflagellates are a major component of the modern plankton. Of the 2192 species of marine free-living dinoflagellates presently described, an increasing number are being shown to produce resting cysts (probably hypnozygotes) within their life cycle. With rare exception, only the resting cysts fossilize, so they are of central importance in tracing the history of dinoflagellates through geological time. Cysts of many of the more common dinoflagellate species have distinctive morphologies allowing their geographic and stratigraphic occurrences to be traced. An ever-increasing number of taxa are also being shown to produce distinctive and geologically preservable cysts, potentially enhancing our knowledge of the diverse representation of dinoflagellates through time. Here the organic-walled cysts of 73 rare, poorly known or morphologically problematic marine dinoflagellate cyst species belonging to the orders Gymnodiniales (nine species) and Peridiniales (64 species) are reviewed, described and illustrated, and their stratigraphic ranges assessed. The names Echinidinium aculeatum and Echinidinium transparantum are validated herein. © 2019 Elsevier B.V.

Metallic glasses (MGs) are promising candidates for catalysts with high efficiency for dyeing wastewater remediation, due to their metastable nature, disordered structure, and large residual stresses. However, dyeing wastewater usually contains a high concentration of inorganic ions which may have adverse effects on the degradation process, while the impacts of these ions on MGs' degradation capability have often been overlooked and still remain unknown. Thus, the roles of inorganic ions (Cl-, NO3-, SO42-, and H2PO4-) on the degradation of azo dye by Fe-based MG with nominal composition of Fe81Si4B14Cu1 were systematically investigated. The results showed that the inorganic ions have significant influence on MG's surface morphology, degradation capability, mineralization and durability. All these aspects need to be considered prior to application of MGs for azo dyes degradation in real natural contaminated water or saline wastewater.

Three-dimensional flowerlike nanostructured metal oxides attached on the surfaces of Fe-based multi-phase nanocrystalline ribbons (Fe-MNRs) were prepared by a simple way (through immersing the Fe-MNRs in Orange II solution). It has been found that the as-prepared Fe-MNRs with 3D flowerlike nanostructures (Fe-MNRs + FNs) exhibit good absorption property for a typical heavy metal ion (CrVI) in wastewater, while Fe-MNRs do not possess such properties. The Fe-MNRs + FNs could remove 99% CrVI ions from the solution in 40 min, and this adsorption property can be attributed to the ion exchange between CrVI and surface hydroxyl groups (O–H) of 3D flowerlike nanostructures. The present result suggests that the Fe-MNRs + FNs, prepared by facile way, possess great potentials in removing heavy metallic ions in wastewater.

A versatile porous adsorbent of sulfonated polystyrene/ferrosoferric oxide/diazoresin (SPS/Fe3O4/DR) nanocomposite microspheres with magnetic property and acidic/basic groups was prepared and applied for removal of different dyes from water. The adsorbent showed good adsorption performance due to its functional groups and strong adsorption forces. The selective removal of methylene blue (MB) from MB/methyl orange (MO) mixture can be realized using this adsorbent. The adsorption uptake capacity of the adsorbents was 223.71 mg/g and the removal efficiency was more than 90% even after five adsorption-desorption cycles. This adsorbent could be readily separated from solution within 2 min using a magnet. Furthermore, adsorption kinetics for SPS/Fe3O4/DR followed by the pseudo-second order model. Isothermal equilibrium data were fitted with Langmuir model, which indicated the adsorption process is the monolayer adsorption. This novel, low cost and high effective adsorbent possesses great potential in environmental pollution cleanup. Keywords: Sulfonated polystyrene, Ferrosoferric oxide, Diazoresin, Adsorption, Dyes

The tight reservoirs have been successfully developed by horizontal wells with massive hydraulic fractures. The inherent heterogeneity along the wellbore, complex fracture networks generated due to the pre-existing natural fracture and stress isotropy, the difference of reservoir properties between the stimulated reservoir volume (SRV) and the unstimulated region all bring huge challenges in predicting pressure and rate transient responses. Previous study always simplified the whole reservoir as homogeneous or radial composite region, and treated the complex networks as orthogonal fracture networks. In the light of this situation, by using the source function, boundary element method and composite reservoir model, a rigorous semi-analytical model for a horizontal well with complex fracture networks in heterogeneous reservoirs was presented in this paper. A previous semi-analytical model and numerical model established by commercial simulator were both used to verify the feasibility of the proposed model. The effects of critical parameters on the transient pressure behaviors are discussed. The results show that heterogeneity of the reservoir has a significant influence on pressure behavior. The sensitivity analysis of fracture number, fracture geometry, storage coefficient and inter-porosity factor of SRV, reservoir sizes and relative position between SRV and the outer boundaries are conducted to further understand the transient pressure behaviors of volume fractured horizontal well. In this paper, both the heterogeneity along the horizontal well in the SRV and the heterogeneity between the SRV and the unstimulated region is brought into consideration. In addition, the complex fracture geometry is also captured. Therefore, our model can be capable of studying the transient pressure behaviors of volume fractured horizontal wells in heterogeneous reservoir. The research results provided by this work have some significance for well test interpretation of tight reservoirs.

Dense patches were observed in the tidal pools of the southern area of Korea. To clarify the causative organisms, the cells were collected and their morphological features were examined using light and scanning electron microscopy (SEM). In addition, after establishing strains for the cells the molecular phylogeny was inferred with concatenated small subunit (SSU) and large subunit (LSU) rRNA sequences. The cells were characterized by a nucleus in the hypotheca, strong reticulations in thecal plates, the separation of plates 2a and 3a, the tear-shaped apical pore complex, an elongated rectangular 1a plate and the absence of the right sulcal list. The thecal plate formula was Po, X, 4′, 3a, 7″, 6c, 4S, 5′′′, 2′′′′. Based on these morphological features, the cells were identified as Bysmatrum subsalsum. In the culture, the spherical cysts of B. subsalsum without thecal plates were observed. Molecular phylogeny revealed two ribotypes of B. subsalsum are identified, The Korean isolates were nested within the ribotype B consisting of the isolates from China, Malaysia and the French Atlantic, whereas the ribotype A includes only the isolates from the Mediterranean Sea. In the phylogeny, B. subsalsum and B. austrafrum were grouped. This can be supported by the morphological similarity between the two species, indicating that the two species may be conspecific, however B. subsalsum may distinguish from B. austrafrum, because of differences in the types of eyespots reported in previous studies. These findings support the idea that there is cryptic diversity within B. subsalsum.

A new phototrophic dinoflagellate, Grammatodinium tongyeonginum gen. & sp. nov., was established by incubating resting cysts collected from surface sediment samples from Tongyeong coastal area, Korea. The resting cysts were ovoid with a large reddish pigment body and surrounded with a thick mucous layer that incorporated attached detritus particles. The vegetative cells were 24.6–40.9 μm long and 16.4–27.3 μm wide. The cell surface was covered with prominent longitudinal equidistant furrows. The cingulum was narrow and descended two to eight times its width. The nucleus was located at the central part of the epicone. The peripheral chloroplasts were usually granular and yellow-green in culture and were distributed along the rim of the cingulum. The horseshoe-shaped apical groove ran from the end of the sulcal extension anticlockwise around the apex. The distal end of the apical groove was located next to the extension of the sulcus and more to the ventral side than the proximal end. Molecular phy...

Outbreaks of paralytic shellfish poisoning (PSP) and dense blooms caused by Alexandrium species in Jinhae-Masan Bay, Korea have been nearly annual events for many years. However, excluding some Alexandrium species responsible for PSP, there are no critical reports on the morphology of Alexandrium species in this bay. To identify the Alexandrium species based on detailed morphological features, vegetative cells collected water samples and established by the incubation of resting cysts isolated from sediment trap samples were analyzed. Four species of Alexandrium were identified: Alexandrium affine, A. fundyense, A. catenella, and A. insuetum. Morphological features of these species were basically consistent with those outlined in previous studies. However, the ventral pore and the connecting pore on the sulcal plate, which have been accepted as diagnostic characteristics for the identification of A. fundyense and A. catenella, need to be reevaluated, indicating that useful morphological features for identifying these two species should be recommended to avoid confusion in the classification of species in genus Alexandrium.

Different from the reported results, multiphase (Fe73.5Si13.5B9Nb3Cu1)91.5Ni8.5 nanocrystalline ribbons (CR-II) show much better degradation capability in Orange II than their metallic glass (MG) counterparts. CR-II ribbons have superior properties, such as high degradation capability, good durability and facile fabrication. In particular, high degradation efficiency could be expected even under an alkaline environment, while most reported zero-valent metals would only be available for acid or neutral environments. Galvanic cells between the α-Fe nanocrystals and intermetallics contribute to the high degradation capability of CR-II by accelerating the α-Fe nanocrystals to lose electrons, leading to the fracture of the azo bond (–NN–). Additionally, 3D nanoporous architectures and 3D flowerlike nanostructure sediments formed during the degradation process are also beneficial to the high degradation capability by promoting mass transport. These findings could provide new clues to design new materials with superior degradation capability and low cost for wastewater treatment.

Fouled anion exchange resins were regenerated by electric field intensification of Mg/Al double-metal hydroxides. Regenerative experiments were performed with varying voltages (10–30 V) and dosages of Mg/Al hydroxides (0.045–0.135 mol and 0.015–0.045 mol, respectively) for 1–5 h. Optimal results were obtained under the following regenerative conditions: 20 V, 4 h, and 0.09/0.03 mol of Mg/Al hydroxides. The maximum regenerative capacity of resins was increased to 41.07%. The regenerative mechanism was presented by Fourier-transform infrared spectrum of resins and Mg/Al hydroxides, and the regenerative degree was analyzed with respect to conductivity, pH value, and electric current. Mg/Al hydroxides were also recycled after the regeneration. This method was proven to be cost-effective and environmentally friendly.

Although the genus Pseliodinium within the family Ceratoperidiniaceae includes Ceratoperidinium falcatum, Cochlodinium cf. convolutum, C. cf. helix and unidentified Cochlodinium species, it is in need of reclassification because of the morphological differences and lack of morphological details of the species within the genus. A Cochlodinium-like species was isolated from a Korean coastal area and examined by light and scanning electron microscopy, as well as by the analysis of nuclear-encoded small subunit (SSU) and large subunit (LSU) rDNA. The Korean isolate was morphologically characterized by cellular torsion, and outer rows consisting of small rectangular and polygonal vesicles were visible along the sides of the cingulum. The apical structure complex (ASC) formed a complete circle surrounding the cell apex, consisting of three parallel rows of vesicles. In the ASC, the upper row was sometimes hidden and very small knobs were present on the central row. Morphological characteristics separated the Korean isolate from Ce. margalefii, Pseliodinium fusus(=Ce. falcatum), Kirithra asteri and Gymnodinium species (Gymnodinium sp. 1 and sp. 2) within the family Ceratoperidiniaceae. However, the morphological characteristics coincided with those of the previously recorded C. convolutum, C. cf. helix and other Cochlodinium species within the same family. Phylogeny based on SSU and LSU rDNA sequences revealed that the Korean isolate forms a clade independent from P. fusus, although they have high sequence similarity. Based on the morphological and phylogenetic analyses, we propose the new genus Torquentidium gen. nov. and a new combination for C. cf. helix and the Korean isolate Torquentidium convolutum erected within the family Ceratoperidiniaceae.

The key to the success of matrix acidizing in carbonate reservoirs depends on the diversion efficiency of treating fluid over the total production interval, especially for treatments on vertical wells with thick formations or horizontal wells with long and heterogeneous intervals. Foamed viscoelastic-surfactant (VES) acid combined the advantage of foam and VES can distribute acid evenly in the entire production interval. However, its diversion capability and wormhole propagation behavior has not been investigated yet. Therefore, the conventional core-flooding setup was modified by adding nitrogen source and foam generator, which was used to conduct single and parallel core-flooding acidizing experiments to investigate the effect of injection rate and initial permeability on wormhole propagation, and evaluate the diversion capability under extreme permeability contrast. Furthermore, in order to characteristic the wormhole morphology, computerized tomography (CT) scanning experiments were performed on the cores after acidizing to generate a 3D view of the wormholes inside the cores. The results of single core-flooding experiments achieved the following findings: 1. The injection rate was found to be a critical parameter in maximizing the acidizing efficiency during the foamed-VES acidizing, and the optimal acid injection rate ranges from 1 mL/min to 2 mL/min under laboratory conditions. 2. The wormhole morphology changes from conical wormhole to dominant wormhole and ramified wormhole with the increase of injection rate. 3. The initial permeability of cores hardly affects the optimal injection rate and wormhole morphology, but the pore volume to breakthrough (PVbt) decreases with the increase of the core initial permeability. 4. The foamed-VES acid has a better temporary plugging capability on the cores with high permeability due to the combined effects of foam's Jamin effect and VES self-viscosified property. The parallel core-flooding experiments show that foamed-VES acid can realize the uniform distribution of acid when the permeability contrast is about 10, and overcome the limitation of conventional VES acid. However, the foamed-VES acid will work ineffectively when the permeability contrast is greater than 20. This study deepens the understanding on the foamed-VES acidizing in carbonate reservoirs and provides fundamental for field acidizing treatment design.

Centrodinium punctatum is a fusiform dinoflagellate with a global marine distribution. Due to a close phylogenetic relationship of one C. punctatum strain to Alexandrium species, toxin production of this C. punctatum strain was assessed using liquid chromatography coupled to tandem mass spectrometry. The paralytic shellfish toxin (PST) profile of C. punctatum was dominated by six analogs, i.e. STX (30%), GTX-1 (20%) and neoSTX (24%), followed by GTX-2 (9%), GTX-4 (9%) and GTX-3 (8%); deoxy-STX was also putatively identified while no gymnodimines, spirolides or goniodomins were detected. This is the first record of C. punctatum producing saxitoxins. The estimated cellular toxicity was rather elevated, between 91 and 212 pg cell−1 (or 259 and 601 fmol cell−1). When considering the toxicity equivalent factors, results suggest that this species can produce high cellular toxicity compared to other STX-producing dinoflagellates. Morphological details of the sulcal area and the hypotheca of Centrodinium punctatum were re-examined by scanning electron microscopy (SEM); this revealed that in the sulcal area, the left posterior sulcal plate (Ssp) is larger and longer than the left posterior sulcal plate and extended into the hypotheca. Based on the morphological observation, a revised interpretation of the sulcus and hypotheca is proposed.

Two new isomers containing pyridine ring diamine monomers, 2,2′-bis[4-(5-amino-2-pyridinoxy)phenyl] propane (1b) and 2,2′-bis[4-(6-amino-3-pyridinoxy)phenyl] propane (2b), were prepared via a simple nucleophilic reaction of 2-chloro-5-nitropyridine and 5-bromo-2-nitropyridine with bisphenol A in the presence of potassium carbonate, respectively. A series of polyimides (PIs) were obtained from the heterocyclic diamine with various commercially available aromatic dianhydrides via the conventional two-step method. These obtained PIs were investigated in aspects of their solubility, thermal, mechanical, and optical properties for studying the effects of the heteroaromatic rings into the main chain. At the same time, the impact of the two isomers introduced into the PI was discussed in detail.

A hybrid material of diazoresin (DR) and ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) coated onto silica particles were synthesized and applied as adsorbents. The study of UV-vis spectrum revealed that DR and EDTA could be successfully modified onto silica. The effect of initial pH value of aqueous solution and dosage of the adsorbents on the adsorption capability for heavy metal Cu(II) ion were investigated and discussed.

The nonlinear stability analysis of a structure with initial geometric imperfections is very complex, difficult, and unsolved yet in designing. At present, there are no unified design guidelines for imperfection sensitive metal shells (spherical, cylindrical, conical, and so forth), and the study about composite shell structures is often for a specific ply parameter and therefore less adaptable. In this paper, the imperfection sensitivity analysis of orthotropic conical shells with and without cutouts under compression is investigated numerically. The eigenmode-shape imperfections and dimple-shape imperfections are introduced to conical shells with different cutout sizes. In order to find the worst imperfections that can reduce the buckling load as far as possible, an optimization framework based on the multiple perturbation load approach is developed by the present authors to search the possible positions of dimple-shape imperfections; the effectiveness of the algorithm has been proved by comparing with other conventional approaches.Mid-surface imperfections, a type of realistic imperfection, transferred from a cylinder are considered for a conical shell with a cutout at last. This work can provide a reference value for conical shell design for practical engineering applications.

The effects of the addition of nutrients (nitrate: N, phosphate: P, and vitamin B1) and trace metals (iron: Fe, Copper: Cu, and selenium: Se) on the growth of Gymnodinium catenatum, which was isolated from Korean coastal waters, were investigated. The Korean isolate of G. catenatum grew under a wide range of concentrations of N and P. Whilst high concentrations of N (&gt, N: P ratio of 23.5) did not stimulate the growth rate, an enhanced growth rate and cell density were observed with the addition of P. The experimental addition of vitamin B1 revealed that G. catenatum is not dependent on vitamin B1 for growth. Moreover, the addition of Fe and Cu resulted in no significant differences in the growth patterns and rates of G. catenatum between the controls and treatments. It is thus possible that growth of the Korean isolate of G. catenatum does not require high concentrations of Fe and Cu. However, the cell densities were enhanced in the stationary phases of treatments upon addition of Se, and the maximum cell densities were higher than those in the culture experiments upon additions of other nutrient and trace metals. Our findings indicate that G. catenatum prefers P and Se for proliferation, rather than other nutritional sources.

In Japanese, Chinese and Korean coastal waters, recurrent blooms of a small, elongate Prorocentrum species have been observed in recent years. In previous studies, this species has been respectively identified as P. shikokuense, P. donghaiense and P. dentatum, despite morphological similarity and identical rDNA sequences. To resolve the confusion, morphological features, including the architectural details of the periflagellar area, were examined and ribosomal DNA (rDNA) sequences were obtained from specimens collected from the East China Sea and Korean coast, and a strain established in the waters off the Canary Islands of Spain. In addition, the descriptions of the three species and allied species were reviewed. Morphological observations and a phylogeny based on the SSU, ITS region and LSU rDNA sequences revealed that the previously confused species and our studied strains are conspecific and that the morphology of strains identified as P. dentatum in the phylogenetic trees does not coincide with P. dentatum sensu stricto. The confusion can be traced back to Dodge (1975, p. 116), who considered P. veloi, P. monacense and P. obtusidens as junior heterotypic synonyms of P. dentatum. However, Dodge’s P. dentatum are closer to P. obtusidens sensu stricto, rather than P. dentatum sensu stricto. P. obtusidens sensu stricto can be distinguished from P. dentatum sensu stricto by its relatively small size, parallel sides towards the anterior and a blunt anterior extension on one side. This indicates that P. obtusidens should not be considered a synonym of P. dentatum sensu stricto. In addition, a comparison of the original descriptions of P. obtusidens and allied species allowed to conclude that small, elongate Prorocentrum from Japanese, Chinese and Korean coastal waters previously identified as P. shikokuense, P. donghaiense, P. dentatum sensu Yoo and Lee (1986) and the specimens studied herein, which share identical rDNA sequences, morphologically coincide with P. obtusidens. Therefore, it is proposed that P. shikokuense and P. donghaiense should be regarded as junior synonyms of P. obtusidens.

The goal of semi-supervised learning is to improve the performance of supervised learning tasks using unlabeled data. Deep learning has a high demand for making use of large-scale unlabeled data. We propose a simple and novel method of utilizing unlabeled data for semi-supervised learning to improve the performance of the deep learning model. First, we train a Gaussian process classifier (GPC), and use its output on unlabeled data as a pseudo-label. Then, we pre-train the deep learning model with the pseudo-labeled data to initialize the parameters of the model. Finally, we fine-tune it with the labeled data. We apply this method to five classes of video from the UCF101 data set which contains a small amount of labeled data. The experiment results show significant performance improvements compared to those of the deep learning model without pre-training. We further study the pre-training effect using pseudo-labeled data with a different probability, and give some advice for practical application. Moreover, we propose to train GPC with stratified sampled data (SGPC) to reduce the computation time of GPC when there are large amounts of data. Finally, we generalize proposed pseudo-labeling method to any classifier having good performance and give some advice for pseudo-labeling method selection.

Despite the importance of understanding the bloom mechanisms that influence cyanobacterial toxin production, the dynamics of toxic Microcystis subpopulations are largely unknown. Here, we quantified both toxic and entire (i.e., toxic and non-toxic) Microcystis populations based on the microcystin synthetase E (mcyE) and 16S ribosomal RNA genes. Samples were collected from pelagic water and sediments twice per week from October to December 2011, and we investigated the effects of physicochemical factors (pH, water temperature, dissolved oxygen, nutrients, etc.) and biological factors (ciliates and zooplankton) on the abundance of toxic and non-toxic Microcystis. During the study period, Microcystis blooms were composed of toxic and non-toxic subpopulations. Resting stage Microcystis in sediment may be closely linked to Microcystis populations in pelagic water and may contribute to the toxic subpopulation composition in surface Microcystis blooms. In pelagic water, the toxic and entire Microcystis population had a significant positive correlation with the pH and water temperature (p

Paralytic shellfish poisoning (PSP) caused the deaths of four people in coastal area of Korea, mainly Jinhae-Masan Bay and adjacent areas, in April 1986 and in 1996. The PSP outbreaks were caused by the consumption of mussels, Mytilus edulis . The organism that caused PSP was identified, from morphological data only, as Alexandrium tamarense which is recently renamed as A. catenella , however recent studies have shown that the morphological diagnostic characteristics used to identify Alexandrium species have uncertainties and molecular tools and other criteria should be considered as well. The organism that caused past PSP outbreaks and incidents in Korea therefore need to be carefully reconsidered. The aim of this study was to re-evaluate the species really responsible for past outbreaks of PSP in Jinhae-Masan Bay, Korea. The temporal production and fluxes of the resting cysts of Alexandrium species were investigated for one year (from March 2011 to February 2012) using a sediment trap, and the morphology and phylogeny of vegetative cells germinated from the resting cysts were analysed. The production of Alexandrium species peaked in August and November, when temporal discrepancies were found in the water temperature (22.4 and 22.7 °C in August, 19.1 and 19.6 °C in November) and salinity (29.5 and 26.1 psu in August, 30.5 and 31.8 psu in November). The morphological data revealed that Alexandrium species germinated from resting cysts collected in August have a ventral pore on the 1′ plate, whereas the 1′ plate in Alexandrium species germinated from resting cysts collected in November lacks a ventral pore. Molecular phylogenetic data for the vegetative cells from the germination experiments allowed the August and November peaks to be assigned to Alexandrium catenella (Group I) and A. pacificum (Group IV), respectively. This indicates that the production of resting cysts of A. catenella can be enhanced by relatively high water temperature. This result is not consistent with those of previous studies that A. catenella responsible for PSP outbreaks was found at relatively low water temperature. In addition, large subunit ribosomal sequences data revealed that A. pacificum isolates from Korea were closely related to those from Australia, Japan and New Zealand where the PSP toxicity of shellfish and blooms occurred in the 1990s, indicating that the introduction of toxic dinoflagellates were related to ballast water from bulk-cargo shipping. Based on these results, we concluded that past PSP outbreaks in Jinhae-Masan Bay of Korea could have been caused by A. pacificum rather than by A. catenella .

While the initiation and development of dense bloom of Cochlodinium polykrikoides have been shown to be related to some environmental factors, little is known about the ecological role of the formation and germination of temporary cysts, nor of their significance for the rapid expansion of dense regional-scale blooms. This study examined the factors affecting the formation and germination of temporary cysts of C. polykrikoides , and provides details about the germination process. In the laboratory experiments, C. polykrikoides produced the chain-forming temporary cysts that are immobile and surrounded by a hyaline membrane. The encystment experiment indicated that darkness induces the formation of chain-forming temporary cysts, consistent with field observation of morphology and fluxes of temporary cysts. Germination occurred twice from a single four-celled temporary cysts within 24 h after exposure to light, and the germlings appeared as two-celled chain-forming vegetative cells. The germination behavior of temporary cysts of C. polykrikoides differs from that of other dinoflagellates, and this may be a survival strategy for the maintenance of population size during dense blooms.

NanoSQUIDs with Dayem nanobridge weak-link junctions were fabricated on single layer niobium film by focus ion beam(FIB) milling. The dimension of the nanobridge is less than 60 nm and the loop scale is from 400×400 nm to 2.5×20 μm. The working temperature range for this device was researched. The voltage-flux transfer properties were measured at different working temperatures.

In this paper we report the progress on single quantum Hall devices for the resistance standards in NIM. We use the NIM-made device and the LEP-made device distributed to NIM by BIPM to calibrate a Tinsley 100 Ω transfer resistor using a cryogenic current comparator (CCC) at the filling factor k=2. The deviations of resistance values from the nominal value were −4.4808×10−6±3.5×10−9 by NIM-1 and −4.4987×10−6±3.5×10−9 by BIPM-2 separately. We assume the relative difference 1.8×10−8 is due to the drift of the 100 Ω transfer resistor. More stable resistor will be used in future experiments.

Anion-exchange resins (AERs) were regenerated with Mg/Al double-metal hydroxides as the regenerant. Electrical conductivity breakthrough curves were adopted to estimate the relatively rapid regenerative effect of the AERs. The results show that the optimal regenerative effect of AER was obtained when the Mg/Al molar ratio was 3 and the dosages of Mg and Al hydroxides were 0.045 and 0.015 mol, respectively. The highest effluent water yield was obtained at an AER/cation-exchange resin volume ratio of 2:1. Characterization through scanning electron microscopy, X-ray diffraction, and thermogravimetry–differential thermal analysis showed that the regenerant was transformed and exhibited the distinguishing features of Mg/Al layered double hydrotalcites. Cycle experimentation showed that all calcined products effectively regenerated the fouled resins, and the regenerative mechanism was then established. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42928.