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Electrical parameters are vital for electrical discharge machining (EDM) process performance. The study utilized the combination of Taguchi and grey relational analysis (GRA) to optimize sinking EDM. Optimization of peak current, pulse duration, duty ratio and electrode lifting time affecting material removal rate (MRR), relative electrode wear rate (REWR) and surface roughness (SR) in sinking EDM. Analysis of variance (ANOVA) shows that peak current and pulse duration significantly affect MRR and REWR, respectively. Peak current and pulse duration significantly affect SR. The optimized parameters were subjected to EDM experiments and the results are 8.54% increase in MRR, 11.11% decrease in REWR and 9.42% decrease in SR. It was found that at a peak current of 1A, the discharge pit not only depends on peak current and pulse duration but also on pulse off time. Compared to conventional optimization methods, this study analyzed the microstructure and recast layer of the workpieces. [ABSTRACT FROM AUTHOR]

Chemical investigation of the Penicillium sp. SCSIO 41038 led to the isolation and characterization of one new cyclopiazonic acid-type alkaloid, speradine I (1), and one new phloroglucinol derivative, speradine J (8), along with 13 known compounds. Their structures were determined on the basis of extensive spectroscopic analysis, and by a comparison with data from the literature. All the compounds were evaluated for their antitumor (22Rv1 and PC-3) and enzyme inhibitory activity against acetylcholinesterase (AChE) in vitro. [ABSTRACT FROM AUTHOR]

The chemical investigation of the EtOAc extract from the solid rice medium cultured with a sponge-associated fungus Penicillium sp. SCSIO41033 led to the isolation of two quinolones including a new one, penicinolone (1), three xanthone derivatives (3–5), and four anthraquinones (6–9). Their structures were determined by comprehensive analysis of 1H and 13C NMR, COSY, HSQC, and HMBC spectroscopic, and HRESIMS mass spectrometric data. The bioactive assays revealed that compounds 1 and 2 showed no antimicrobial activities against five bacteria and eight fungi, and compounds 5, 8 and 9 exhibited inhibition against AChE with IC50 values of 45.9, 42.5 and 40.5 μg/mL. Molecular docking analysis was performed to explore the interactions between active molecules and AChE protein, which indicated that xanthone and anthraquinone derivatives had the potential for developing AChE inhibitors. [ABSTRACT FROM AUTHOR]

This study aimed to explore the pressure sensitivity of the external ear that can be the basis for adapting the pressure distribution on the concha for in-ear earphone design. Overall, 30 participants were included in this study, where an electronic mechanical algometer with a stepping motor was used to apply constant pressure. Before the experiment, the customised concha shell models of the participants were positioned in the ear perpendicular to the concha surface. Furthermore, the pressure discomfort threshold (PDT), moderate pressure discomfort (MPD), and maximum pressure threshold (MPT) in eight regions of the ear were recorded. This study's results indicate that the four regions of the external ear are less sensitive to pressure than those of the other regions. Additionally, women had higher pressure sensitivity values in the external ear. Therefore, this study's findings could have important implications for earphone designs and evaluating discomfort conditions in the external ear. Practitioner summary: This study explores the pressure sensitivity threshold (PDT, MPD, and MPT) on the external ear and the relevant implications for in-ear earphone design. Interestingly, regions closer to the bone structure were less sensitive to pressure, and men could tolerate greater pressure on the external ear than women. [ABSTRACT FROM AUTHOR]

A new anthraquinone, asperquinone A (1), and four known anthraquinone derivatives 2–5 were isolated from the mangrove endophytic fungus Aspergillus sp. 16-5C. These structures were elucidated by spectroscopic analysis and the absolute configuration of 1 was unambiguously determined by ECD calculation. Compounds 1–5 showed no significant inhibitory effect against Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB). [ABSTRACT FROM AUTHOR]

An insufficient number of ground support vehicles and improper dispatch have a significant impact on the quality of airport services. The reasonable dispatch of airport special vehicles can greatly improve the efficiency of airport services. In this paper, a bi-objective mixed-integer programming model is proposed which takes the minimum number of vehicles required and minimum total extra time cost of special vehicles as objectives. Additionally, the service constraint relationship of various vehicles and the reusable nature of vehicles to make full use of existing special vehicle resources are considered. To easily solve the model, the comprehensive scheduling problem is reduced to several sub-problems with parallel services and timing constraints. A non-dominated sorting genetic algorithm with multiple chromosomes and an elite strategy are developed to solve them separately. Finally, using the actual flight data of a domestic airport, we demonstrate the effectiveness of the proposed model and offer useful managerial insights. [ABSTRACT FROM AUTHOR]

The present work reports the bioassay-guided isolation of four bioactive fatty acid derivatives involving a new butenolide, namely sinulolide I (1) together with three known metabolites (2–4) from the deep-sea sediment derived fungus Aspergillus terreus SCSIO 41202. The chemical structure of compound 1 was elucidated based on extensive spectroscopic methods (1D/2D NMR and HR-ESI-MS), optical rotation and circular dichroism analyses, while the structures of the known compounds (2–4) were established by comparison of NMR spectral data with those reported in literature. All of these four compounds (1–4) exhibited significant antifungal activity against citrus postharvest pathogen Penicillium italicum (MICs around 0.031–0.125 mg/mL). [ABSTRACT FROM AUTHOR]

Stichopus ocellatus, known as eye-spotted sea cucumber, is a commercially important Stichopodidae holothuroid in Indo-Pacific region for its valuable nutrition and medicinal ingredients. However, because the taxonomic analyses based on morphological characters and molecular data within Aspidochirotida are limited, the deep-level evolutionary relationships of Aspidochirotida are still poorly understood. Here, for providing better insight of future evolutionary and taxonomic classification of Stichopodidae, we report the first complete mitogenome of S. ocellatus along with 37 annotated and characterized mitochondrial genes, and the phylogenetic analysis based on mitogenome data reveals sister relationship between S. ocellatus and S. monotuberculatus. [ABSTRACT FROM AUTHOR]

Over 70% of the cities in China are experiencing urbanization, and urban heat island intensity (UHII) evaluation studies have been widely performed. However, under the rapid economic development in China, few studies on surface urban heat island (SUHI) interannual variations have been conducted in coastal cities in the leading economic region of the Yangtze River Delta. In this study, the long-term summer daytime SUHI from 2001 to 2019 is studied based on the remotely sensed land surface temperature (LST) in 11 coastal cities in the Yangtze River Delta. The results show that notable SUHIs occur in the study area with high spatial heterogeneity, particularly in the central area, including Shanghai, Hangzhou, and Ningbo. The SUHI trends are not synchronous across the study area, with suburban areas revealing higher trends than city center areas. In addition, all 11 cities show an increasing trend of the urban heat proportion index (UHPI) over 19 years, which is more profound in Shanghai and Zhoushan but less profound in Lianyungang and Wenzhou. The strong correlation between the UHPI and artificial impervious coverage indicates that artificial impervious coverage plays an important role in determining the spatial and temporal distributions of the summer daytime SUHI in the 11 coastal cities, which are especially notable in Ningbo and Taizhou. [ABSTRACT FROM AUTHOR]

Two new polyketides, xerucitrinin A (1) and coniochaetone M (8), and one new steroid, 16α-methylpregna-17α,19-dihydroxy-(9,11)-epoxy-4-ene-3,18-dione-20-acetoxy (13), together with eleven known analogues were isolated from fungus Penicillium citrinum SCSIO 41017 associated with the sponge Callyspongia sp. Their structures and absolute configurations were elucidated by NMR spectra, MS, CD, optical rotation, X-ray crystallography, and compared with literature data. Biological evaluation results revealed that 5 exhibited significant cytotoxic activity against MCF-7 cell line with IC50 values of 1.3 μM. Compound 13 showed moderate activity against all cell lines with IC50 values of 13.5–18.0 μM, and compounds 9 and 14 showed weak activity with MIC values of ranging from 125 μg/mL to 250 μg/mL respectively. [ABSTRACT FROM AUTHOR]

Application of the electric field to water-in-oil system can accelerate the coalescence of droplets. However, when an excessively high electric field is applied, droplets will exhibit break-up behavior. In addition to the strength of the electric field, the salt type in droplets significantly affects their break-up behavior. However, the break-up behavior of droplets containing the same valence cation is rarely investigated, and the mechanism underlying the influence of ionic type remains unclear. In this study, the break-up behavior of droplets containing chlorine salt with the same valence cation is studied by molecular dynamics simulations. The influences of electric field strength and ionic type on the break-up behavior of droplets are analyzed. Simulation results demonstrate that the droplet deformation increases with the increase in the electric field, and the droplets break when the degree of deformation exceeds a critical value. The ionic type mainly affects the break-up time of droplets through drift velocity, which is proportional to the electric field strength and ionic mobility. Moreover, from Na+ to Cs+, the cationic mobility increases first and then decreases with the increase of crystallographic radius. [ABSTRACT FROM AUTHOR]

A new griseofulvin derivative, eupenigriseofulvin (1), together with six known compounds, griseofulvin (2), dechlorogriseofluvin (3), dechloroisogriseofulvin (4), trichopyrone (5), 2-(4-hydroxyphenyl)-ethanol (6), and 1-phenylethane-1,2-diol (7), were isolated from the EtOAc extract of Eupenicillium sp. SCSIO41208. The structures of these compounds were elucidated by spectroscopic methods including NMR and mass spectrometry. The absolute configuration of 1 was determined on the basis of electronic circular dichroism (ECD) data analysis. [ABSTRACT FROM AUTHOR]

Superalloys are typical "difficult to machine" materials, which could be processed by electrical discharge machining (EDM). The studies about the machining performance of superalloys mainly concentrate on nickel-based superalloys and titanium superalloys. But for iron-based superalloys, such as GH2132, which has an extensive application in numerous fields, the investigations are seldom conducted. A high energy die-sinking EDM is proposed in this paper, and the deionized water is used as the dielectric. The machining performance of GH2132 through the proposed machining method is systemically investigated. Taguchi L25 orthogonal array (L25) is utilized to investigate the influences of machining parameters (peak current (I), pulse on time (Ton), and pulse off time (Toff)) on output indexes (material removal rate (MRR), relative electrode wear rate (REWR), and diameter overcut (DOC)). Single-objective optimization is performed to acquire maximum MRR, minimum REWR, and DOC by analysis of variance (ANOVA). The optimal machining performance, which is better than the results from L25, is also obtained by gray relation analysis (GRA) and multi-objective optimization. [ABSTRACT FROM AUTHOR]

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The most common dielectric in sinking electrical discharge machining (EDM) is kerosene. However, kerosene is inflammable; besides, it can be decomposed and release harmful gases during machining process. And, owing to its low viscosity, using kerosene in sinking EDM has low machining efficiency. Accordingly, conventional sinking EDM using kerosene as dielectric has poor safety, unfriendly environment impact, and low machining efficiency. A new water-in-oil (W/O) nanoemulsion is presented in this paper. This W/O nanoemulsion not only can eliminate the hazards from kerosene to operator and environment but also improve the machining performance of conventional sinking EDM. This research aims to experimentally investigate the machining performance of W/O nanoemulsion in comparison with kerosene in sinking EDM at relatively low discharge energy. The effects of electrode material, electrode polarity, peak current, and pulse duration on machining performance are studied. The machined surface and recast layer of workpiece are characterized as well. The experimental results demonstrate that compared with kerosene, using W/O nanoemulsion in sinking EDM can obtain a higher material removal rate (MRR), a lower relative electrode wear rate (REWR), and a machined workpiece with fewer defects and thinner recast layer. [ABSTRACT FROM AUTHOR]

The marine fungus Emericella sp was isolated from the deep sea sediments. The fungus was identified by its morphology and ITS region. A new emerixanthone E (1) together with four (2–5) known emodin derivatives were isolated from the metabolites of the fungus Emericella SCSIO05240. The structures were elucidated on the basis of NMR spectroscopic analysis and mass spectrometry. The biological properties of those compounds (1–5) were explored for antimicrobial, antifungal and antitumor activity. [ABSTRACT FROM AUTHOR]

Marine micro-organisms have been proven to be excellent sources of bioactive compounds against HIV-1. Several natural products obtained from marine-derived Aspergillus fungi were screened for their activities to inhibit HIV-1 infection. Penicillixanthone A (PXA), a natural xanthone dimer from jellyfish-derived fungus Aspergillus fumigates, displayed potent anti-HIV-1 activity by inhibiting infection against CCR5-tropic HIV-1 SF162 and CXCR4-tropic HIV-1 NL4-3, with IC50 of 0.36 and 0.26 μM, respectively. Molecular docking study was conducted to understand the possible binding mode of PXA with the CCR5/CXCR4. The results revealed that, the marine-derived PXA, as a CCR5/CXCR4 dual-coreceptor antagonist, presents a new type of potential lead product for the development of anti-HIV therapeutics. [ABSTRACT FROM AUTHOR]

Marine micro-organisms in the deep-sea hydrothermal vent systems are considered as potential sources of bioactive natural products. Sixteen bacterial strains were isolated from a deep-sea hydrothermal field and screened for bioactive metabolism studies. After the strains were subjected to bioactive testing at different culture media, chemical dereplication by HPLC coupled to high-resolution mass spectrometer was performed to analyse or determine the main secondary metabolisms in those strains. Strain 06204 was large-scale fermented with relative optimal media, for isolating the desired sulphur compound. Butyrolactone I 3-sulphate was isolated and structurally identified from the extract, guided by dereplication and showed moderate antivirus activities against H3N2 and EV71 viruses. Our study suggests that deep-sea hydrothermal bacteria are good sources of sulphur natural products. Meanwhile, the described approach, mainly bioactive screening, dereplication and targeted isolation, is effective and efficient to discover interesting bioactive compounds in hydrothermal bacteria. [ABSTRACT FROM AUTHOR]

From the deep-sea-derived bacterium Bacillus subterraneus 11593, a new indole alkaloid (1) was isolated along with three known compounds (2‒4). By detailed analysis of its NMR spectroscopic data, and further by the theoretical ECD calculations, the absolute configuration of the new compound was determined to be (R)-N-[2-(3-hydroxy-2-oxoindolin-3-yl)ethyl]acetamide, and named bacilsubteramide A. All four isolates were tested for anti-allergic bioactivities; however, none exhibited positive effect (IC50 > 0.2 mM). Noteworthily, it is the first report on secondary metabolites from the bacterium B. subterraneus. [ABSTRACT FROM AUTHOR]

Aim of the study: Thiopurines are effective drugs in treating neuromyelitis optica spectrum disorders and other diseases. Thiopurines’ toxicity is mainly imputed to thiopurine S-methyltransferase activity. In Chinese population, the most common and important variation of thiopurine S-methyltransferase is TPMT*3C (rs1142345). This study aims to reveal the association between thiopurine S-methyltransferase activity and genetic polymorphisms of thiopurine S-methyltransferase in patients with neuromyelitis optica spectrum disorders in China. Material and methods: A liquid chromatography tandem mass/mass method was used to evaluate the thiopurine S-methyltransferase activity by using 6-mercapthioprine as the substrate in human erythrocyte haemolysate via 1 h incubation at 37 °C to form its methylated product 6-methylmercaptopurine. The amount of 6-methylmercaptopurine was adjusted by haematocrit and normalized to 8 × 108 erythrocytes. The selected polymorphisms of thiopurine S-methyltransferase were identified using MassARRAY system (Sequenom) and multiple SNaPshot technique. Results: In 69 patients with neuromyelitis optica spectrum disorders, thiopurine S-methyltransferase activity was 80.29-154.53 (127.51 ± 16.83) pmol/h/8 × 108 erythrocytes. TPMT*3C (rs1142345) was associated with lower thiopurine S-methyltransferase activity (BETA = −25.37, P = 0.011). Other selected variants were not associated with thiopurine S-methyltransferase activity. Conclusions: TPMT*3C affects TPMT activity in Chinese patients with neuromyelitis optica spectrum disorders. Further studies are warranted to confirm the results. Abbreviations:TPRs = thiopurines; NMOSD = neuromyelitis optica spectrum disorders; TPMT = thiopurine S-methyltransferase; LC-MS/MS = liquid chromatography tandem mass/mass; 6-MMP = 6-methylmercaptopurine; IS = internal standard; SNP = single nucleotide polymorphism; MAF = minor allele frequency; HWE = Hardy-Weinberg equilibrium; BETA = regression coefficients; UTR-3 = untranslated region 3 [ABSTRACT FROM AUTHOR]

The growing public opposition to p-xylene (PX) project proposals in China requires understanding the divergence between the general public's risk perception and environmental risk assessment (ERA) results and its implications on its decision-making. In a case study in Fujian Province of China, a questionnaire was designed to investigate the public perception of risks of a proposed PX project, interviews were further conducted in Zhangzhou City and Xiamen City, and the survey results were compared with the ERA results of the proposed PX project. Results indicate that the environmental risk is acceptable according to current technical ERA guidelines and standards, while the public acceptance of the PX project is very low. The underlying factors causing the difference between the general public's risk perception and ERA results were identified from the ERA technical perspective. A better understanding of the risk perception divergence from different disciplinary perspectives is helpful for the public acceptance of these kinds of projects, which are on high demand in China. This study not only highlights the necessity to improve the risk communication but also provides insights on future research of ERA for this kind of large-scale project proposal. [ABSTRACT FROM AUTHOR]

Three new polyketides named trichbenzoisochromen A (1), 5,7-dihydroxy-3-methyl -2-(2-oxopropyl)naphthalene-1,4-dione (2) and 7-acetyl-1,3,6-trihydroxyanthracene-9,10- dione (3) together with six known compounds (4–9) were isolated from a sponge-derived fungus Trichoderma sp. SCSIO41004. The structures of three new polyketides (1–3) were determined by the extensive spectroscopic analysis, including 1D, 2D NMR and HRESIMS data. The absolute configuration of compound 1 was confirmed by the specific optical rotation value and CD spectra analyses. Compound 4 exhibited significant inhibitory activity against EV71 with the IC50 value of 25.7 μM. [ABSTRACT FROM AUTHOR]

Eleven diketopiperazine and fumiquinazoline alkaloids (1–11) together with a tetracyclic triterpenoid helvolic acid (12) were obtained from the cultures of a deep-sea derived fungus Aspergillus sp. SCSIO Ind09F01. The structures of these compounds (1–12) were determined mainly by the extensive NMR, ESIMS spectra data and by comparison with previously described compounds. Besides, anti-tuberculosis, cytotoxic, antibacterial, COX-2 inhibitory and antiviral activities of these compounds were evaluated. Gliotoxin (3), 12,13-dihydroxy-fumitremorgin C (11) and helvolic acid (12) exhibited very strong anti-tuberculosis activity towards Mycobacterium tuberculosis with the prominent MIC50 values of <0.03, 2.41 and 0.894 μM, respectively, which was here reported for the first time. Meanwhile gliotoxin also displayed significant selective cytotoxicities against K562, A549 and Huh-7 cell lines with the IC50 values of 0.191, 0.015 and 95.4 μM, respectively. [ABSTRACT FROM AUTHOR]

Fifteen compounds, including six quinone/hydroquinone meroterpenoids, purpurogemutantin (1), macrophorin A (2), 4′-oxomacrophorin (3), 7-deacetoxyyanuthone A (4), 2,3-hydro-deacetoxyyanuthone A (5), 22-deacetylyanuthone A (6), anicequol (7), three roquefortine derivatives, roquefortine C (8), (16S)-hydroxyroquefortine C (9), (16R)-hydroxyroquefortine C (10), dihydroresorcylide (11), nectriapyrone (12), together with three fatty acid derivatives, methyl linoleate (13), phospholipase A2 (14), methyl elaidate (15), were isolated from the sponge-derived fungus Gliomastix sp. ZSDS1-F7 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by extensive NMR spectroscopic and mass spectrometric analyses. Among these compounds, compounds 1–3 and 5–7 showed significant in vitro cytotoxicities against the K562, MCF-7, Hela, DU145, U937, H1975, SGC-7901, A549, MOLT-4 and HL60 cell lines, with IC50 values ranging from 0.19 to 35.4 μM. And compounds 2–4 exhibited antitubercular activity with IC50 values of 22.1, 2.44 and 17.5 μM, respectively. Furthermore, compound 7 had anti-enterovirus 71 activity with MIC value of 17.8 μM. To the best of our knowledge, this is the first report to product two quinone/hydroquinone meroterpenoids skeletons (linear skeleton and drimane skeleton) from the same fungal strain. [ABSTRACT FROM AUTHOR]

A three-step model of the transitional phase inversion (TPI) process for the formation of water-in-oil (W/O) emulsions is presented. Three types of emulsions exist in an emulsification process at different oil–water ratios and hydrophilic–lipophilic balance (HLB). A stable W/O emulsion was obtained using Sorbitan oleate (Span 80) and polyoxyethylenesorbitan monooleate (Tween 80) with a specified HLB and oil volume fraction. Oil was added into water, which contained the water-soluble surfactant, to dissolve the oil-soluble surfactant. This route allowed TPI to occur, and an interesting emulsification process was observed by varying the HLB, which corresponded to the change in the oil–water ratio. Two types of emulsions in the emulsification process were found: transition emulsion 1 (W/O/W high internal phase emulsion) and target emulsion 2 (W/O emulsion with low viscosity). This study describes the changes that occurred in the emulsification process. [ABSTRACT FROM AUTHOR]

Compound machining (CM) compounded by arc machining and electrical discharge machining (EDM) milling is a new and fast processing method used to machine so-called “difficult-to-machine” materials. This method has an exciting maximum material removal rate that reaches 11,218 mm3/min with the relative electrode wear rate (REWR) of 1.54% when machining Inconel718. The electrode material is an important factor that affects the processing cost and quality of CM. Traditionally used electrode materials in arc machining and EDM, including pure tungsten (W), cerium tungsten (WCe20), copper (Cu), tungsten copper alloy (W80), and graphite (C), were used as electrode materials to process Inconel718. Experimental results show that tubular C is the best electrode material for CM. When tubular C is unavailable, WCe20 is the suitable electrode material for rough machining and W is a better choice in finish machining. Cu electrode is unsuitable for CM because of its low melting point. Results of this work provide guidance for selecting electrode materials for the industry application of efficient CM. [ABSTRACT FROM AUTHOR]

Two new phenyl derivatives (1 and 3), along with two new natural products (4 and 5), and three known compounds (2, 6 and 7), were isolated from an endophytic fungus Botryosphaeria sp. SCSIO KcF6. The structures of these compounds 1–7 were elucidated by the extensive 1D and 2D-NMR and HRESIMS Data analysis, and compared with those of reported data. The absolute configuration of the compounds 1 and 3 were assigned by optical rotation and CD data. The isolated compounds were evaluated for their cytotoxic, anti-inflammatory (COX-2) and antimicrobial activities. Compound 3 exhibited a specific COX-2 inhibitory activity with the IC50 value of 1.12 μM. [ABSTRACT FROM AUTHOR]

Context: Pinellia ternata (Thunb.) Berit., a perennial herb belonging to Araceae, is one of the few medicinal plants to produce purine alkaloids. It is speculated that endophytic bacteria from P. ternata may produce guanosine or inosine. However, there is no report about endophytic bacteria in P. ternata. Objective: In this study, endophytic bacteria were isolated from P. ternata and examined for the first time. This study finds a novel way to increase the yield of P. ternata herb, and to provide some new alkaloid producers. Materials and methods: Plant material includes leaves, tubers, and roots of cultivated and wild P. ternata. The dilutions were smeared onto beef extract-peptone medium and cultured at 28 °C in darkness for 48-72 h. Co-culture treatments were prepared by inoculating 100 mL liquid 1/2 MS medium with bacterial culture broth at concentrations of 0 (control), 0.5%, and 1.5% (v/v). Results: Of the 34 endophytic bacterial colonies isolated from P. ternata leaves, roots, and tubers, five strains were able to produce purine alkaloids . Results from 16s rDNA sequence analysis indicated that the bacteria belonged to Bacillus cereus, Aranicola proteolyticus, Serratia liquefaciens, Bacillus thuringiensis, and Bacillus licheniformis. Co-culture with living Serratia liquefaciens cells increased PLB growth by 58-71%. Co-culture with living Bacillus licheniformis cells increased PLB growth by 4-11%. Conclusion: This study provides a novel way for improving the yield of P. ternata herb, and for the production of purine alkaloids by the fermentation industry. [ABSTRACT FROM AUTHOR]

Echinoderms (Echinodermata) are morphologically diverse and ecologically important groups of marine invertebrate, many of which are key components of local benthic ecosystem. However, due to morphological plasticity and limited molecular phylogenetic studies, the taxonomic histories in echinoderms have not been completely resolved. The phylogenetic relationships of Phyllophoridae genera and species remain controversial and many species are incorrectly assigned within genus Phyrella. In this study, we report the first complete mitochondrial genome of Phyrella from Phyrella fragilis. The mitogenome has 15,910 base pairs (64.32% A + T content) and is made up of a total of 37 genes (13 protein-coding, 22 transfer RNAs and 2 ribosomal RNAs), plus a putative control region. This study will provide useful genetic data for future phylogenetic and taxonomic classification of Phyllophoridae. [ABSTRACT FROM AUTHOR]

The white-bottomed sea cucumber, Actinopyga lecanora, is a valuable inshore fisheries resource which is famous for its high nutrition and pharmacological compounds. However, due to morphological plasticity and limited molecular phylogenetic studies, the taxonomic histories in the genus Actinopyga have not been completely resolved yet. Moreover, there remains a complex of cryptic species within Actinopyga, many of which are incorrectly assigned within the family Holothuriidae. In this study, we report the complete mitochondrial genome of A. lecanora. The mitogenome has 15,568 base pairs (63.40% A + T content) and is made up of a total of 37 genes (13 protein-coding, 22 transfer RNAs and 2 ribosomal RNAs), plus a putative control region. This study offers useful mitogenome data for future phylogenetic and taxonomic classification of Holothuriidae. [ABSTRACT FROM AUTHOR]

Sea urchins (Echinoidea) are key components of marine benthic communities and many are commercially important fishery resources as luxury and healthy seafood. However, despite their high ecological and economic value, the mitochondrial genomes of all sea urchins have yet to be analyzed. In this study, we report the first complete mitochondrial genome of Stomopneustidae from Stomopneustes variolaris. The mitogenome has 15,767 base pairs (59.77% A + T content) and contains 37 genes (13 protein-coding, 22 transfer RNAs and 2 ribosomal RNAs), plus a putative control region. This study provides useful molecular resources for clarifying evolutionary and phylogenetic histories of sea urchins. [ABSTRACT FROM AUTHOR]

Fifteen compounds, including two tetramic acid derivatives, penicillenol A1 (1) and penicillenol A2 (2), six polyphenols containing both phenolic bisabolane sesquiterpenoid and diphenyl ether units, expansols A–F (3–8), together with six phenolic bisabolane sesquiterpenoids (9–14) and diorcinol (15), were isolated from the fermentation broth of the marine-derived fungus ZSDS1-F11 isolated from the sponge Phakellia fusca Thiele collected in the Yongxing island of Xisha. Their structures were elucidated mainly by using extensive NMR spectroscopic and mass spectrometric analyses. Compounds 3–5, 7 and 8 showed potent COX-1 inhibitory activity with IC50 values of 5.3, 16.2, 30.2, 41.0 and 56.8 μM, respectively. Meanwhile, compounds 3–8 showed potent COX-2 inhibitory activity with IC50 values of 3.1, 5.6, 3.0, 5.1, 3.2 and 3.7 μM, respectively. In addition, compound 1 exhibited antituberculosis activity with 96.1% inhibition at concentration of 10 μM. [ABSTRACT FROM AUTHOR]

The bouncing motion of aqueous drops between two oppositely charged electrodes has been observed. However, the forward and backward velocities of the drops are nonuniform in some cases because of unknown reasons. In this study, the velocity difference was mainly caused by the distribution of ions that altered the electric field strength between the electrodes. This result yielded accurate control of the drops in the electric field and opened opportunities for industrial applications. [ABSTRACT FROM PUBLISHER]

A new citromycetin analogue, ascomycotin A (1), together with eight known compounds, wortmannilactone E (2), orcinol (3), orsellinic acid (4), isosclerone (5), (3R,4S)-( − )-4-hydroxymellein (6), diorcinol (7), chaetocyclinone B (8) and 2,5-dimethoxy-3,6-di(p-methoxypheny1)-1,4-benzoquinone (9), was isolated from the fungal strainAscomycotasp. Ind19F07, which was isolated from the deep sea sediment of the Indian Ocean. The structures of the compounds were established by spectroscopic data including 1D and 2D NMR and HR-ESI-MS. Compounds (1–9) were evaluated for antibacterial activity. [ABSTRACT FROM PUBLISHER]

One new briarane-type diterpenoid, dichotellide V (1), along with four known analogues, gemmacolide N (2), dichotellide J (3), junceelin A (4) and junceellolide A (5), was isolated from the South China Sea gorgonianDichotella gemmacea. All of the isolated compounds (1–5) were established by comprehensive analysis of the spectral data, especially 1D and 2D NMR (HMQC and HMBC) spectra. The cytotoxic activities of these compounds were evaluated. [ABSTRACT FROM PUBLISHER]

In this study, the dehydration of water-in-oil emulsion subjected to an electric field was investigated both experimentally and via computer simulation. The time evolution of the droplets subjected to an electric field was investigated using optical microscopy. We also implemented a computer simulation of the dynamic behavior of the droplets resulting from the balance of forces applied on them. The probability of coalescence between droplets as well as coalescence between droplets and the water/oil interface was also investigated. Thus, the behavior of the droplets could be observed more directly, and the problem could be solved stochastically and mathematically. Through adjustment of the values of the two coalescence probabilities, the simulated results could accurately represent the actual process. [ABSTRACT FROM AUTHOR]

A new methyl 2-(4-((2-hydroxy-3-methylbut-3-en-1-yl)oxy)phenyl) acetate 1, together with five known compounds 2–6, was isolated from the culture of the deep sea-derived fungus Aspergillus westerdijkiae SCSIO 05233. The new structure was determined by NMR (1H and 13C NMR, HSQC, HMBC and MS) and optical rotation analysis. Compound 5 displayed weak inhibitory activities towards K562 and promyelocytic HL-60 with IC50 values of 25.8 and 44.9 μM, and compound 6 showed strong antifouling activity with EC50 value 8.81 μg/mL. [ABSTRACT FROM AUTHOR]

Axinelline A, a new cyclooxygenase-2 (COX-2) inhibitor, was isolated from Streptomyces axinellae SCSIO02208. The structures of compounds 1–9 were determined by analysing the NMR and MS data. The absolute configuration of 1 was determined by using optical rotation and comparing with the reported data. Compound 1 exhibited COX-2 inhibitory activity, the IC50 value being 2.8 μM. [ABSTRACT FROM AUTHOR]

One new naphthalene derivative, 1,8-dihydroxynaphthol-1-O-α-l-rhamnopyranoside (1), together with one known α-dibenzopyrone, alternariol (2), and five xanthones (3–7) were isolated from the sponge-derived fungus Arthrinium sp. ZSDS1-F3. All the isolated compounds (1–7) were established by comprehensive analysis of the spectral data, especially 1D and 2D NMR (HMQC and HMBC) spectra. In the primary bioassays, compound 3 exhibited moderate COX-2 inhibition, with IC50 values of 12.2 μM. [ABSTRACT FROM AUTHOR]

Chemical investigation of the fungus Xylariaceae sp. DPZ-SY43 has led to the isolation of a new compound, xylaolide A (1) together with three known compounds (2–4). The structures were established by analysing the spectroscopic data. Compound 1 was evaluated for its cytotoxicity. [ABSTRACT FROM AUTHOR]

Many cutting operations are necessary for tubular structures and the wellhead during platform decommission. Electric arc cutting technology for casing and wellhead inner cutting is presented in this study. The electric arc cutting system eliminates the plasma gas system and focuses only on high cutting efficiency given that this cutting operation has no requirements on dimensional accuracy. An arc ignition circuit that is different from traditional arc cutting power is introduced. This study aims to explore cutting performance, such as cutting efficiency and electrode wear. Several cutting parameters, including the working medium, electrode material, electrode diameter, cutting current, and workpiece thickness, are investigated by a series of experiments to analyze cutting performance. Cutting time and electrode wear rate are obtained to evaluate the cutting performance. The morphological features of the experimental results are also investigated. Results show that electric arc cutting technology can be employed to cut a workpiece effectively in sea water with a 4mm tungsten electrode. Cutting performance is affected significantly by cutting current and velocity. A 13 3/8inch casing is cut within 5min in the laboratory with optimal machining parameters, which allow for a good cutting effect. [ABSTRACT FROM PUBLISHER]

Context: Epidioxy sterols and sterols with special side chains, such as hydroperoxyl sterols, usually obtained from marine natural products, are attractive for bioactivities. Objective: To isolate and screen bioactive and special sterols from China Sea invertebrates. Materials and methods: Two hydroperoxyl sterols ( 1 and 2) from the sponge Xestospongia testudinaria Lamarck (Petrosiidae), three epidioxy sterols ( 3- 5) from the sea urchin Glyptocidaris crenularis A. Agassiz (Glyptocidaridae), sponge Mycale sp. (Mycalidae) and gorgonian Dichotella gemmacea Milne Edwards and Haime (Ellisellidae) and an unusual sterol with 25-acetoxy-19-oate ( 6) also from D. gemmacea were obtained and identified. Using high-throughput screening, their bioactivities were tested toward Forkhead box O 3a (Foxo3a), 3-hydroxy-3-methylglutaryl CoA reductase gene fluorescent protein (HMGCR-GFP), nuclear factor kappa B (NF-κB) luciferase, peroxisome proliferator-activated receptor-γ co-activator 1α (PGC-1α), protein-tyrosine phosphatase 1B (PTP1B), mitochondrial membrane permeabilization (MMP) and adenosine monophosphate-activated protein kinase. Results: Their structures were determined by comparing their nuclear magnetic resonance data with those reported in the literature. Three epidioxy sterols ( 3- 5) showed inhibitory activities toward Foxo3a, HMGCR-GFP and NF-κB-luciferase with the IC50 values 4.9-6.8 μg/mL. The hydroperoxyl sterol 29-hydroperoxystigmasta-5,24(28)-dien-3-ol ( 2) had diverse inhibitory activities against Foxo3a, HMGCR-GFP, NF-κB-luciferase, PGC-1α, PTP1B and MMP, with IC50 values of 3.8-19.1 μg/mL. Discussion and conclusion: The bioactivities of 3- 5 showed that 5α,8α-epidioxy is the active group. Otherwise, the most plausible biosynthesis pathway for 1 and 2 in sponge involves the abstraction of an allylic proton by an activated oxygen, such as O2, along with migration of carbon-carbon double bond. Therefore, the bioactive and unstable steroid should be biosynthesized in sponge under a special ecological environment to act as a defensive strategy against invaders. [ABSTRACT FROM AUTHOR]

A new (1) and two known (2 and 3) acylated taurine derivatives were isolated from the South China Sea marine sponge Axinella sp. The structures of the compounds were determined on the basis of spectral analysis. Compounds 1–3 did not inhibit the growth of hepatoma carcinoma cell (HepG2), lung carcinoma cell (A549), human breast carcinoma (MCF-7), no-small cell lung cancer (NCI-H460) and human nasopharyngeal carcinoma cell lines. [ABSTRACT FROM AUTHOR]

This article proposes a high current density electrical discharge milling for machining Inconel 718. The proposed power supply comprises a pulse generator with high voltage and a DC power source with high current. The pip graphite electrode and the workpiece are connected to the negative and positive poles of the power supply, respectively. Benefiting from efficient flushing and high current density, the maximum material removal rate (MRR) achieved 15,062 mm3/min with a relative electrode wear ratio (REWR) of 1.73%. The effects of peak current and injection flushing pressure on the MRR and REWR were investigated. Experiments showed little differences between the thickness of recast layer with the peak currents of 150 A and 920 A, and the thickness was less than 50 µm. It is also evident that the microcracks within the recast layer penetrated into the base material and propagated along the grain boundar. [ABSTRACT FROM AUTHOR]

Micro-electric discharge machining (micro-EDM) has become an important issue in the fabrication of microcomponents, especially after the development of the wire electro discharge grinding (WEDG) technology. However, the fabrication of microelectrodes through the WEDG technology is very complicated and time consuming, which limits the extensive industrial application of micro-EDM. This article reports the feasibility of utilizing carbon fiber as the electrode in micro-EDM. A novel chucking method and device are developed to chunk the extremely slender carbon fiber. The experiment results show that carbon fiber is a promising material in micro-EDM. [ABSTRACT FROM AUTHOR]

The true crabs (Brachyura) including Calappidea are one of the most diverse groups of Decapod crustaceans However, despite their great diversity and commercial importance, phylogenetic and classification relationships within Calappidea are still complicated and controversial. In this study, we report the first complete mitochondrial genome of Matuta victos. The mitogenome has 17,782 base pairs (70.1% A + T content) and is made up of a total of 37 genes (13 protein-coding, 22 transfer RNAs and two ribosomal RNAs), plus a putative control region. This study will provide useful molecular resources for clarifying evolutionary and phylogenetic confusion within Calappidea. [ABSTRACT FROM AUTHOR]

Miters including Mitra chinensis are important fishery resources in China. However, the phylogenetic and taxonomic studies in Mitridae have been limited. In this study, we report the first complete mitochondrial genome of M. chinensis. The mitogenome has 16,238 base pairs (66.9% A + T content) and is made up of a total of 37 genes (13 protein-coding, 22 transfer RNAs, and two ribosomal RNAs), plus a putative control region. This study will provide useful molecular resources for addressing taxonomic and evolutionary issues in Neogastropoda. [ABSTRACT FROM AUTHOR]

The common frogsnail Bufonaria rana, is an ecologically and economically important Tonnoideans in China due to valuable nutrition and pharmacological compounds. However, the taxonomy and phylogeny of the Bursidae have been debated and synonyms among Bursidae species have been reported recently. In this study, we report the first complete mitochondrial genome of Bursidae from B. rana. The mitogenome has 15,510 base pairs (69.0% A + T content) and made up of total of 37 genes (13 protein-coding, 22 transfer RNAs and 2 ribosomal RNAs), and a putative control region. This study was the first available complete mitogenomes of Bursidae and will provide useful genetic information for future phylogenetic and taxonomic classification of Tonnoideans. [ABSTRACT FROM AUTHOR]

Phascolosoma is one of the most important genera of Sipuncula, many species of which including P. scolops are economic important species in the fishery of southeast China. However, the synonym and misidentification of species in Phascolosoma have been reported repeatedly. Here, we report the complete mitochondrial genome sequence of P. scolops. The mitogenome has 15,515 base pairs and made up of total of 38 genes (13 protein-coding, 23 transfer RNAs and 2 ribosomal RNAs), and a putative control region. The complete mitogenomes of P. scolops will contribute to further phylogenetic and taxonomic study in the genus Phascolosoma. [ABSTRACT FROM AUTHOR]