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In this study, Inconel 625 weldments with different Nb contents were prepared via shielded metal arc welding followed by aging heat treatment. The microstructures of the resulting weldments were observed using scanning electron microscopy/energy-dispersive X-ray spectroscopy. The fabrication process used in this study resulted in the partial formation of the γ" (750 °C), δ (850 °C), and M6C carbide (950 °C) phases in the weldments. The electron backscattering diffraction results revealed that with an increase in the Nb content, the secondary phase fraction of the weldments increased. Potentiodynamic polarization tests were carried out to evaluate the pitting corrosion resistance of the weldments. With increasing Nb content of the weldments, the fraction of the passive region increased at 750 and 850 °C. The corrosion and formal potentials of the weldment with 4.26 wt% Nb decreased after the heat treatment at 950 °C, resulting in a relatively small passive region. Double loop-potentiokinetic reactivation tests were carried out to evaluate the sensitization of the weldments to interphase corrosion. The degree of sensitization increased with increasing Nb content when the heat treatment was carried out at 750 and 850 °C. The δ-phase showed lesser effect on the interphase corrosion resistance of the weldments than the γ" phase. The specimen with 4.26 wt% Nb heat-treated at 950 °C showed high degree of sensitization to interphase corrosion.

Terpenoids are naturally occurring compounds involved in respiration, photosynthesis, membrane fluidity, and pathogen interactions and are classified according to the structure of their carbon skeleton. Although most terpenoids possess pharmacological activity, knowledge about terpenoid metabolism in medicinal plants is insufficient. Rehmannia glutinosa (R. glutinosa) is a traditional herb that is widely used in East Asia and has been reported to contain various terpenoids. In this study, we performed a comprehensive transcriptome analysis of terpenoid metabolism in R. glutinosa using two RNA sequencing platforms: Illumina and PacBio. The results show that the sterol, saponin, iridoid, and carotenoid pathways are active in R. glutinosa. Sterol and saponin biosynthesis were mevalonate pathway dependent, whereas iridoid and carotenoid biosynthesis were methylerythritol 4-phosphate pathway dependent. In addition, we found that the homologous genes of key enzymes involved in terpenoid metabolism were expressed differentially and that the differential expression of these genes was associated with specific terpenoid biosynthesis. The different expression of homologous genes encoding acetyl-CoA acetyltransferase, 3-hydroxy-3-methylglutaryl-CoA reductase, mevalonate kinase, mevalonate diphosphate decarboxylase, farnesyl pyrophosphate synthase, squalene synthase, and squalene epoxidase was associated with sterol and saponin biosynthesis. Homologous genes encoding 1-deoxy-D-xylulose 5-phosphate synthase were also differentially expressed and were associated with carotenoid and iridoid biosynthesis. These results suggest that the biosynthesis of specific terpenoids can be regulated by the homologous of key enzymes involved in plant terpenoid metabolism.

Ultra-dense network (UDN) has been considered a promising solution to improve the signal quality of cell edge UEs and enhance the serving coverage. However, a large number of small cells causes severe inter-cell interference and high energy consumption, and efficient small cell management is an important issue. In this paper, a UE throughput guaranteed small cell on/off algorithm in UDN environment is proposed to solve the problem of UE throughput reduction due to small cell off process. The proposed small cell on/off algorithm with machine learning is executed by the following processes: First, the network attributes that affect UE throughput are analyzed. Second, the correlation between UE throughput and network attributes is evaluated through multiple linear regression analysis. Third, through understanding the correlation between UE throughput and network attributes, we determine the proper criteria for small cell on/off process. Simulation results show that the proposed small cell on/off algorithm can improve the total network energy efficiency as well as efficiently ensure sufficient UE throughput. Compare to the conventional algorithm, the proposed algorithm shows more than 75% improvements of average network energy efficiency. whole network.

Rehmannia glutinosa (RG) is a widely cultivated medicinal crop in Korea. Its rhizomes are commonly distributed in dried form as a food or traditional medicine. However, very little research into the drying methods for R. glutinosa has been conducted. This study was performed to determine the effect of the drying temperature on the quality characteristics of R. glutinosa. The famous domestic cultivar ‘Dagang’ was used for the study. The drying experiments were carried out at 40, 50, 60, 70, and 80°C in a hot air dryer. All samples were dried until their moisture content was less than 12%; the moisture content of the raw root was 78.97±1.27%. Under the hot-air drying conditions, the drying process required 288 h at 40°C, 144 h at 50°C, 45 h at 60°C, 22 h at 70°C, 12 h at 80°C. The physical properties of RG were different for each drying temperature. When the temperature was increased, the lightness color value decreased. Hardness which is an important texture factor, was high for a drying temperature of 50–60°C and relatively low for 40°C, 70°C, and 80°C. The catalpol content increased with increasing temperature up to 70°C, and then decreased at higher temperature. Considering the overall characteristics of the dried RG, hot-air drying at 60°C is optimal to achieve desirable physical properties and high active content. These results should provide useful information for the manufacture of high-quality dried RG.

Dinoflagellates are an important group of phytoplanktons, characterized by two dissimilar flagella and distinctive features of both plants and animals. Dinoflagellate-generated harmful algal blooms (HABs) and associated damage frequently occur in coastal areas, which are concomitant with increasing eutrophication and climate change derived from anthropogenic waste and atmospheric carbon dioxide, respectively. The severe damage and harmful effects of dinoflagellate phycotoxins in the fishing industry have been recognized over the past few decades, and the management and monitoring of HABs have attracted much attention, leaving aside the industrial application of their valuable toxins. Specific modes of action of the organisms’ toxins can effectively be utilized for producing beneficial materials, such as Botox and other therapeutic agents. This review aims to explore the potential industrial applications of marine dinoflagellate phycotoxins; furthermore, this review focuses on their modes of action and summarizes the available knowledge on them.

The deleted in azoospermia like (DAZL) is required for germ cells development and maintenance. In chickens, the mRNA and protein of DAZL, a representative maternally inherited germ plasm factor, are detected in the germ plasm of oocyte, zygote, and all stages of the intrauterine embryos. However, it is still insufficient to explain the origin and specification process of chicken germ cells, because the stage at which the zygotic transcription of DAZL occurs and the stage at which the maternal DAZL RNA/protein clears have not yet been fully identified. Moreover, a comprehensive understanding of the expression of DAZL interacting genes during the germ cells specification and development and zygotic genome activation (ZGA) is lacking in chickens. In this study, we identified a set of DAZL interacting genes in chickens using in silico prediction method. Then, we analyzed the whole-transcriptome sequencing (WTS)-based expression of DAZL and its interacting genes in the chicken oocyte, zygote, and Eyal-Giladi and Kochav (EGK) stage embryos (EGK.I to EGK.X). In the results, DAZL transcripts are increased in the zygote (onset of transcription), maintained the increased level until EGK.VI, and decreased from EGK.VIII (possible clearance of maternal RNAs). Among the DAZL interacting genes, most of them are increased either at 1st ZGA or 2nd ZGA, indicating their involvement in germ cells specification and development.

Lectins have the ability to bind specific carbohydrates and they have potential applications as medical and pharmacological agents. The unique structure and usefulness of red algal lectin have been reported, but these lectins are limited to a few marine algal groups. In this study, a novel mannose-binding lectin from Grateloupia chiangii (G. chiangii lectin, GCL) was purified using antiviral screens and affinity chromatography. We characterized the molecular weight, agglutination activity, hemagglutination activity, and heat stability of GCL. To determine the carbohydrate specificity, a glycan microarray was performed. GCL showed strong binding affinity for Maltohexaose-&beta, Sp1 and Maltoheptaose-&beta, Sp1 with weak affinity for other monosaccharides and preferred binding to high-mannan structures. The N-terminal sequence and peptide sequence of GCL were determined using an Edman degradation method and LC-MS/MS, and the cDNA and peptide sequences were deduced. GCL was shown to consist of 231 amino acids (24.9 kDa) and the N-terminus methionine was eliminated after translation. GCL possessed a tandem repeat structure of six domains, similar to the other red algal lectins. The mannose binding properties and tandem repeat structure of GCL may confer it the potential to act as an antiviral agent for protection against viral infection.

The algal cell wall is a potent barrier for delivery of transgenes for genetic engineering. Conventional methods developed for higher plant systems are often unable to penetrate or remove algal cell walls owing to their unique physical and chemical properties. Therefore, we developed a simple transformation method for Chlamydomonas reinhardtii using commercially available enzymes. Out of 7 enzymes screened for cell wall disruption, a commercial form of subtilisin (Alcalase) was the most effective at a low concentration (0.3 Anson units/mL). The efficiency was comparable to that of gamete lytic enzyme, a protease commonly used for the genetic transformation of C. reinhardtii. The transformation efficiency of our noninvasive method was similar to that of previous methods using autolysin as a cell wall-degrading enzyme in conjunction with glass bead transformation. Subtilisin showed approximately 35% sequence identity with sporangin, a hatching enzyme of C. reinhardtii, and shared conserved active domains, which may explain the effective cell wall degradation. Our trans­formation method using commercial subtilisin is more reliable and time saving than the conventional method using autolysin released from gametes for cell wall lysis.

Pyropia tenera is an intertidal red alga of commercial significance owing to its popularity as a health-promoting seafood product. This alga grows in marine environments and is frequently exposed to high salinity and osmotic stress, which impact its growth. Therefore, the enhancement of stress tolerance in P. tenera is critical. In the present work, we aimed to elucidate the mechanisms underlying abiotic stress tolerance in this species; specifically, we identified the P. tenera S-adenosylmethionine synthetase-encoding gene (PtSAMS) and characterized its biological function. This gene, which is known to play a role in stress tolerance in other plants, was cloned and overexpressed in Escherichia coli under high-salinity conditions. The PtSAMS gene was found to encode a 385-amino-acid protein with a molecular weight of 41.8 kDa. In silico sequence alignment and phylogenetic analysis of the PtSAMS amino acid sequence showed that the encoded protein comprises three conserved domains and two motifs that are highly conserved in other plants. Growth assay results indicated that PtSAMS-overexpressing E. coli cells exhibit enhanced tolerance to salt stress. The results suggest that PtSAMS expression is induced by a combination of ion toxicity and osmotic stress resulting from exposure to high salinity in marine environments, and that this gene is expressed at housekeeping levels owing to growth in such conditions. The findings suggest that PtSAMS could be used as a potentially valuable bioresource with utility in the genetic engineering of salt stress-tolerant crop plants.

Lectins have the ability to bind specific carbohydrates and they have potential applications as medical and pharmacological agents. The unique structure and usefulness of red algal lectin have been reported, but these lectins are limited to a few marine algal groups. In this study, a novel mannose-binding lectin from Grateloupia chiangii (G. chiangii lectin, GCL) was purified using antiviral screens and affinity chromatography. We characterized the molecular weight, agglutination activity, hemagglutination activity, and heat stability of GCL. To determine the carbohydrate specificity, a glycan microarray was performed. GCL showed strong binding affinity for Maltohexaose-β-Sp1 and Maltoheptaose-β-Sp1 with weak affinity for other monosaccharides and preferred binding to high-mannan structures. The N-terminal sequence and peptide sequence of GCL were determined using an Edman degradation method and LC-MS/MS, and the cDNA and peptide sequences were deduced. GCL was shown to consist of 231 amino acids (24.9 kDa) and the N-terminus methionine was eliminated after translation. GCL possessed a tandem repeat structure of six domains, similar to the other red algal lectins. The mannose binding properties and tandem repeat structure of GCL may confer it the potential to act as an antiviral agent for protection against viral infection.

S-adenosylmethionine (SAM) is widely involved in variety of biosynthetic processes. It participates in the methionine (Met) metabolic pathway. SAM synthetase (EC 2.5.1.6) is the main enzyme that creates SAM from Met and adenosine triphosphate. SAMS genes are highly conserved in different species. We have isolated SAMS genes from red algae, Pyropia tenera. It has been reported that SAMS genes can confer abiotic stress-related response and growth of plant organs in other species. To elucidate the function of PtSAMS gene in evolutionary perspective, we analyzed SAMS gene using bioinformatics tools and plant transformation of Arabidopsis.

Photosynthesis in the ciliate Mesodinium rubrum is achieved using a consortium of cryptophyte algal organelles enclosed in its specialized vacuole. A time-series microarray analysis was conducted on the photosynthetic ciliate using an oligochip containing 15,654 primers designed from EST data of the cryptophyte prey, Teleaulax amphioxeia. The cryptophycean nuclei were transcriptionally active over 13 weeks and approximately 13.5% of transcripts in the ciliate came from the sequestered nuclei. The cryptophyte nuclei and chloroplasts could divide in the ciliate, which were loosely synchronized with host cell division. A large epigenetic modification occurred after the cryptophyte nuclei were sequestered into the ciliate. Most cryptophyte genes involved in the light and dark reactions of photosynthesis, chlorophyll assimilation, as well as in DNA methylation, were consistently up-regulated in the ciliate. The imbalance of division rate between the sequestered cryptophyte nuclei and host nuclei may be the reason for the eventual cessation of the kleptoplastidy.

The algal cell wall is a potent barrier for delivery of transgenes for genetic engineering. Conventional methods developed for higher plant systems are often unable to penetrate or remove algal cell walls owing to their unique physical and chemical properties. Therefore, we developed a simple transformation method for Chlamydomonas reinhardtii using commercially available enzymes. Out of 7 enzymes screened for cell wall disruption, a commercial form of subtilisin (Alcalase) was the most effective at a low concentration (0.3 Anson units/mL). The efficiency was comparable to that of gamete lytic enzyme, a protease commonly used for the genetic transformation of C. reinhardtii. The transformation efficiency of our noninvasive method was similar to that of previous methods using autolysin as a cell wall-degrading enzyme in conjunction with glass bead transformation. Subtilisin showed approximately 35% sequence identity with sporangin, a hatching enzyme of C. reinhardtii, and shared conserved active domains, which may explain the effective cell wall degradation. Our trans-formation method using commercial subtilisin is more reliable and time saving than the conventional method using autolysin released from gametes for cell wall lysis.