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On the basis of the structure of nicotlactone A (

AMPA receptors (AMPARs) mediate the majority of excitatory transmission in the brain and enable the synaptic plasticity that underlies learning1. A diverse array of AMPAR signalling complexes are established by receptor auxiliary subunits, which associate with the AMPAR in various combinations to modulate trafficking, gating and synaptic strength2. However, their mechanisms of action are poorly understood. Here we determine cryo-electron microscopy structures of the heteromeric GluA1–GluA2 receptor assembled with both TARP-γ8 and CNIH2, the predominant AMPAR complex in the forebrain, in both resting and active states. Two TARP-γ8 and two CNIH2 subunits insert at distinct sites beneath the ligand-binding domains of the receptor, with site-specific lipids shaping each interaction and affecting the gating regulation of the AMPARs. Activation of the receptor leads to asymmetry between GluA1 and GluA2 along the ion conduction path and an outward expansion of the channel triggers counter-rotations of both auxiliary subunit pairs, promoting the active-state conformation. In addition, both TARP-γ8 and CNIH2 pivot towards the pore exit upon activation, extending their reach for cytoplasmic receptor elements. CNIH2 achieves this through its uniquely extended M2 helix, which has transformed this endoplasmic reticulum-export factor into a powerful AMPAR modulator that is capable of providing hippocampal pyramidal neurons with their integrative synaptic properties. Analyses of AMPA receptor–auxiliary subunit complexes provide insights into the gating and modulation of the AMPA receptor by TARP-γ8 and CNIH2.

Biliary-stent implantation has become an effective treatment for patients with malignant obstructive jaundice caused by hepatobiliary carcinoma. Stent restenosis due to tumor ingrowth is a common problem. In this study, we assessed a biodegradable form of magnesium (Mg) for its anticancer effect on hepatobiliary carcinoma, compared to the conventional stent material of titanium (Ti). The results showed that a Mg extract inhibited proliferation and induced apoptosis in human cholangiocarcinoma cells, while a Mg plate inhibited cell adhesion and destroyed the cytoskeleton in the process of biodegradation. In animal experiments with H22 tumor-bearing mice, Mg wires implanted in tumors exhibited an inhibitory effect on their growth compared with Ti wires. Fifteen days after implantation of metal wires, the mean tumor volume and weight in the Mg group were significantly smaller than in the Ti group. We observed the dynamic-degradation process of Mg wires in tumors and generation of H2 gas via soft X-ray photography and scanning electron microscopy. Histopathological analyses showed that apoptosis of tumor cells around Mg wires significantly increased, expression of carbonic anhydrase 9 significantly decreased, and the upstream protein hypoxia-inducible factor 1-alpha also decreased to some extent. Taken together, these results indicated that biodegradable Mg had antitumor properties both in vitro and in vivo, suggesting its potential application as a novel material for biodegradable biliary stents.

Data science has maintained its popularity for about 20 years. This study adopts a bottom-up approach to understand what data science is by analyzing the descriptions of courses offered by the data science programs in the United States. Through topic modeling, 14 topics are identified from the current curricula of 56 data science programs. These topics reiterate that data science is at the intersection of statistics, computer science, and substantive fields.

Stimulating learners’ engagement in a large class is one of the most important issues for language educators (Lamb, 2017). The present review aims to offer a review of Mentimeter for creating interactive presentations in large language classrooms. Driven by the continuous development of mobile technologies, language educators and teachers apply ‘Bring Your Own Device’ (BYOD) approach in using technology in classes. BYOD allows teachers and students to use their personally owned device and invite them to actively participate in various forms of in-class activities (Stowell, 2015). Mentimeter is an engaging and interactive Learner Response System (LRS). It allows real-time interaction between language educators and learners via mobile devices. At present, Mentimeter has over 200 million users, and 90,000 customers across more than 220 countries and territories (Mentimeter, 2021), and the application of this tool in language education deserves a deep and critical review.

To achieve global sustainable development and actively respond to climate change, China, as the world’s largest energy consumer and carbon emitter, needs to save energy and reduce emissions without delay. By constructing LEAP-China production-side and LEAP-China consumption-side models, we predict the carbon emissions of China’s production side and consumption side in different scenarios from 2020 to 2050, respectively. The results show that under the current policies, neither the production side nor consumption side can achieve targeted peak carbon emissions by 2030, which is contrary to China’s current carbon emission policy. Under the sustainable development scenario, China’s production-side CO2 emissions would peak at 10,462.2 Mt in 2029, and China’s consumption-side CO2 emissions would peak 3 years later compared to the production side at 9904.3 Mt in 2032. Therefore, to achieve the peak for both the production and consumption side, we need to coordinate various policies and actively promote industrial restructuring and energy structure optimization. In terms of trade structure, China’s existing import and export trade structure should be adjusted to reduce the export of industrially manufactured goods and increase the proportion of technology-intensive products in foreign trade to realize the transformation from a high-carbon trade structure to a low-carbon trade structure.

ObjectivesDirect inhibition of M1 polarization of synovial macrophages may be a useful therapeutic treatment for OA and OA-associated synovitis. Frugoside (FGS) is a cardiac glycoside compound isolated and extracted from Calotropis gigantea. Cardiac glycosides possess interesting anti-inflammatory potential. However, the corresponding activity of FGS has not been reported. Therefore, our aim was to find direct evidence of the effects of FGS on synovial macrophage M1 polarization and OA control.MethodsCollagenase was used to establish an experimental mouse OA model (CIOA) with considerable synovitis. Then, FGS was intra-articular administered. The mRNA and protein levels of iNOS were analysed by real-time PCR and Western blotting in vitro. Immunohistochemical and immunofluorescence staining were used to measure the expression of F4/80, iNOS, Col2α1 and MMP13 in vivo. The levels of pro-inflammatory cytokines in FGS-treated M1 macrophage culture supernatants were analysed by flow cytometry.ResultsFGS attenuates synovial inflammation and delays the development of OA in CIOA mice. Further results demonstrate that FGS inhibits macrophage M1 polarization in vitro and in vivo, which subsequently decreases the secretion of IL-6 and TNF-α, in turn delaying cartilage and extracellular matrix (ECM) degradation and chondrocyte hypertrophy. FGS inhibits macrophage M1 polarization by partially downregulating miR-155 levels.ConclusionThis study demonstrates that intra-articular injection of FGS is a potential strategy for OA prevention and treatment, even at an early stage of disease progression. This is a novel function of FGS and has promising future clinical applications.

Three-dimensional (3D) Ag–ZnFe2O4-reduced graphene oxide (rGO) was successfully synthesized using a hydrothermal and photo-reduction method, and the morphological differences of the materials were observed. Their photocatalytic activity was evaluated by photocatalytic degradation of enrofloxacin (ENR) under visible-light irradiation. The results indicated that Ag–ZnFe2O4–rGO exhibited superior photocatalytic properties and good stability. In this research, the enhancement of photocatalytic performance is mainly attributed to the electron channelization ability of rGO, which traps the photoexcited electrons of ZnFe2O4 on its π framework, and reduces the electron–hole recombination rate. Moreover, the high surface area of 3D pompon mum flower-like ZnFe2O4 provides more reactive sites. In addition, free radical capture and ESR experiments as well as pathway analysis of degradation also confirmed that superoxide radicals (˙O2−) and photo-generated holes from Ag–ZnFe2O4–rGO were the main active species in the degradation progress of ENR.

Traditional industrial process control activities relevant to multi-objective optimization problems, such as proportional integral derivative (PID) parameter tuning and operational optimizations, always demand for process knowledge and human operators’ experiences during human-computer interactions. However, the impact of human operators’ preferences on human-computer interactions has been rarely highlighted ever since. In response to this problem, a novel multilayer cognitive affective computing model based on human personalities and pleasure-arousal-dominance (PAD) emotional space states is established in this paper. Therein, affective preferences are employed to update the affective computing model during human-machine interactions. Accordingly, we propose affective parameters mining strategies based on genetic algorithms (GAs), which are responsible for gradually grasping human operators’ operational preferences in the process control activities. Two routine process control tasks, including PID controller tuning for coupling loops and operational optimization for batch beer fermenter processes, are carried out to illustrate the effectiveness of the contributions, leading to the satisfactory results.

Dopamine (DA) is an important neurotransmitter associated with many diseases. It is very significant to detect DA with high sensitivity and good selectivity. Here, a sensitive and selective electrogenerated chemiluminescence (ECL) aptasensing method was developed for the determination of DA based on target-induced conformational displacement. An anti-DA specific aptamer spliting into two ss-DNA (S1 and S2) was used as molecular recognition elements while an ss-DNA labeled with ferrocene (Fc-CS1, complementary to S1) was used as quenching probe. An ECL platform was prepared by dropping the mixture of Nafion, gold nanoparticles (AuNPs) and Ru(bpy)

Purpose Fluoroquinolone-resistant Shigella is considered a serious public health problem and has been put on the WHO global priority list of antibiotic-resistant bacteria. This study was aimed to investigate the fluoroquinolone resistance in Shigella and its relevant genetic mechanisms. Materials and methods Shigella isolates that were isolated from diarrheal patient's feces in Ningbo China from 2011 to 2018 were tested for susceptibility to ampicillin, gentamicin, tetracycline, nalidixic acid, ciprofloxacin, and cefotaxime. Genes related to quinolone resistance were amplified by PCR. Results A total of 118 Shigella isolates were collected, including 76 S. flexneri isolates, 40 S. sonnei isolates, and 2 S. boydii isolates. Ciprofloxacin susceptibility test identified 10 (9%) susceptible, 65 (55%) intermediate, and 43 (36%) resistant isolates. Of 76 S. flexneri isolates, 37 were ciprofloxacin resistant, a prevalence significantly higher than 6 of 40 S. sonnei isolates (P=0.01). The isolates collected during 2014-2018 displayed a significant increase in the prevalence of ciprofloxacin resistance (P=0.05) than those collected during 2011-2013. All the ciprofloxacin-intermediate and resistant isolates had mutations of gyrA(S83L) and parC (S80I), whereas only the ciprofloxacin-resistant isolates had gyrA (D87N) mutation and qnrB gene. Additionally, 30% of the ciprofloxacin-resistant isolates were positive for aac(6´)-Ib-cr gene. Conclusion This study shows the currently increasing prevalence of ciprofloxacin resistance. The reduced fluoroquinolone susceptibility is highly associated with gyrA (S83L) and parC (S80I) mutations, while the fluoroquinolone resistance is highly associated with gyrA (D87N) mutation, qnrB gene and perhaps aac(6´)-Ib-cr gene.

Air bubbles formed between layers of two-dimensional (2D) materials not only are unavoidable but also emerge as an important means of engineering their excitonic emission properties, especially as controllable quantum light sources. Measuring the actual spatially resolved optical properties across such bubbles is important for understanding excitonic physics and for device applications; however, such a measurement is challenging due to nanoscale features involved which require spatial resolution beyond the diffraction limit. Additional complexity is the involvement of multiple physical effects such as mechanical strain and dielectric environment that are difficult to disentangle. In this paper, we demonstrate an effective approach combining micro-photoluminescence measurement, atomic force microscope profile mapping, and a theoretical strain model. We succeeded in reconstructing the actual spatial profiles of the emission wavelengths beyond the diffraction limit for bubbles formed by a monolayer tungsten disulfide on boron nitride. The agreements and consistency among various approaches established the validity of our approach. In addition, our approach allows us to disentangle the effects of strain and dielectric environment and provides a general and reliable method to determine the true magnitude of wavelength changes due to the individual effects across bubbles. Importantly, we found that micro-optical measurement underestimates the red and blue shifts by almost 5 times. Our results provide important insights into strain and screening-dependent optical properties of 2D materials on the nanometer scale and contribute significantly to our understanding of excitonic emission physics as well as potential applications of bubbles in optoelectronic devices.

Previous studies have shown the operational potential in political discourse analysis from the proximization perspective. This study adopts a cross-disciplinary approach to analyze political communication across transcultural contexts, especially in the cyber discourse space. Based on the spatial–temporal–axiological (STA) model, we compare the journalistic discourses on two social media platforms by China Xinhua News Agency (CXNA), an official speaker for China worldwide. The corpuses are constructed with microblogs on Weibo in Chinese and Twitter in English containing key words of Sino–US trade war. It is found that the speaker has shaped different realities of discourse in accordance with the cultural contexts and proximized from corresponding dimensions to increase political legitimacy.

SPARC is a cysteine-rich acidic secreted protein. It is a non-collagen component of bone, which is widely distributed in humans and animals and plays an important role. SPARC has been found in a variety of human cancers (breast cancer, stomach cancer, ovarian cancer, etc.) and diabetes-related research. Especially the muscle and fat metabolism are closely related. In this study, we used a DNA pool to detect a new SNP site (g.12454T > C). A total of 616 samples of four breeds of Qinchuan cattle (QC, n=176), Xianan cattle (XN, n=160), Pinan cattle (PN, n=136) and Jiaxian cattle (JX, n=144) were analyzed and identified with ARMS-PCR. In addition, we correlated SNP with growth traits and showed significant correlation with growth traits such as rump length, hip width, and body length (p

Strain GS-14T was isolated from a mangrove sediment sample collected at Beilun Estuary National Nature Reserve, Guangxi Province, PR China. Cells were Gram-stain-negative, strictly aerobic and rod-shaped with a polar flagellum. Optimal growth occurred in the presence of 3–6 % (w/v) NaCl, at pH 6–8 and at a temperature of 37 °C. The predominant polar lipids were phosphatidylglycerol and phosphatidylethanolamine. Ubiquinone 8 (Q-8) was the sole respiratory quinone. The major fatty acids (>10 % of the total fatty acids) were summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) and C16 : 0. The DNA G+C content was 47.6 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain GS-14T had the highest sequence similarity to Aestuariibacter aggregatus WH169T (96.63 %), Aliiglaciecola coringensis AK49T (96.56 %) and Alteromonas lipolytica JW12T (96.22 %). In addition, the OrthoANIu value and dDDH values calculated from the genomes of strain GS-14T and A. aggregatus WH169T were 79.5 and 21.9 %, respectively. Based on the polyphasic taxonomic results, strain GS-14T is considered to represent a novel species in a new genus, for which the name Marisediminitalea mangrovi gen. nov., sp. nov. is proposed. The type strain of Marisediminitalea mangrovi is GS-14T (=KCTC 72401T=MCCC 1K03622T). Because Aestuariibacter aggregatus WH169T clustered with strain GS-14T in the phylogenetic trees and was clearly separated from the two species within the genus Aestuariibacter , it is reclassified as a member of the genus Marisediminitalea as Marisediminitalea aggregata comb. nov. (type strain WH169T=CGMCC 1.8995T=LMG 25283T). The type species of the genus Marisediminitalea is Marisediminitalea aggregata gen. nov., comb. nov.

Enhancing structural components by implementing sensors offers great potential regarding condition monitoring for lifetime analysis, predictive maintenance and automatic adaptation to environmental conditions. This article describes an approach to determining the operational forces applied to the front suspension arm of a car using strain gauges. Since suspension arms are components with free-form surfaces, an analytical calculation of applied forces by means of measured strains is not feasible. Hence, artificial neural networks are applied to approximate the functional relationship. The results reveal how artificial neural networks can be applied to identify load conditions on structural components and, therefore, deliver essential data for condition monitoring.

Two new octa-coordinated ternary europium(III) complexes of the type [Eu(btfa)3(Br2-bpy)] (Eu-1) and [Eu(btfa)3(PhE2-bpy)] (Eu-2) (where btfa = 4,4,4-trifluoro-1-phenyl-1,3-butanedione, Br2-bpy = 5,5′-dibromo-2,2′-bipyridine, PhE2-bpy 5,5′-bis(phenylethynyl)-2,2′-bipyridine) together with a previously reported complex [Eu(btfa)3(bpy)] (Eu-3) have been synthesized. The complexes have been characterized by analytical and spectroscopic methods. The photophysical properties of the complexes have also been analyzed both experimentally and theoretically. The contribution of each ligand to the sensitized Eu(III) photoluminescence (PL) has been analyzed and is discussed. An energy transfer (ET) mechanism is proposed and discussed for the sensitized Eu(III) emission using experimental and theoretical data. The Eu(III) complex incorporating the parent bpy showed impressive performance as a double-emitting layer (EML) red organic light emitting diodes (R-OLEDs).

Single-photon emitters were fabricated on hexagonal Boron-Nitride sheets by a femtosecond laser with the yield at 42.86%, photon purity up to 94%, and the corrected saturation intensity at 7.09 Mcps, all best record numbers.

A series of tetrakis lanthanide complexes with the general formula [Ln(hfaa) 4] -(DpaH) + [Ln = (Sm-1), (Eu-1) and (Tb-1)], hfaa = hexafluroacetylacetonate and Dpa −2,2′-dipyridylamine] has been synthesized by the reaction of LnCl 3, hfaa and Dpa in the presence of ammonia solution (25%). The complexes have been characterized by analytical and spectroscopic methods. The solution molecular structure of the complexes was elucidated by one- and two-dimensional NMR spectroscopy which shows that the DpaH + cation retains a close interaction with the lanthanide anion in solution. The crystal structure of Eu-1, determined by single crystal X-ray diffraction, confirms this intermolecular interaction in the solid-state through a N–H⋯O hydrogen bond of 2.187 Å. In the [Eu(hfaa) 4] - anion the EuO 8 coordination polyhedron has a distorted triangular dodecahedron geometry with approximate D 2d-symmetry around the metal centre. Photophysical, thermal, and electroluminescent properties of the complexes have been investigated. The Sm-1 and Eu-1 complexes displayed efficient typical red emission with a sizeable photoluminescence quantum yield (PLQY) while Tb-1 displayed near-white light emission. The complexes have been used as dopants to fabricate single- and double-emitting layer (EML) OLEDs through the thermal evaporation method. At the optimum doping concentration, double-EML Eu-1 based device displayed orange electroluminescence (EL) with a brightness (B) of 417 cd/m 2 and very low V turn-on = 3.4 V. Interestingly, the Sm-1 based single-EML device exhibited pure red emission with the Commission internationale de l'éclairage [(CIE) x,y = 0.613, 0.321], which is rare. The Sm-1 based device performance [B = 145 cd/m 2, current efficiency (η c) = 0.35 cd/A, power efficiency (η p) = 0.15 lm/W with an external quantum efficiency (EQE) = 0.3% and V turn-on = 7.1 V] surpassed that of the only reported Sm-based single red-OLED (R-OLED).

A novel Gram-stain-negative, strictly aerobic bacterium that has a rod-like shape with a single polar flagellum in the exponential phase of growth and a spherical or ovoid shape without a flagellum in the stationary phase was isolated from a mangrove wetland sediment sample collected at Beilun Estuary National Nature Reserve, Guangxi Province, PR China and designated strain ZS-4T. This strain grew optimally at pH 6.0–8.0, at a temperature of 37 °C and in the presence of 3–4 % (w/v) NaCl. Its polar lipid profile included phosphatidylethanolamine, phosphatidylglycerol, one unidentified aminophospholipid and two uncharacterized lipids. Ubiquinone 8 (Q-8) was the sole respiratory quinone and the cellular fatty acids were dominated by C17 : 1ω8c and C16 : 0. A phylogenetic analysis based on the 16S rRNA gene sequence showed that strain ZS-4T exhibited its highest similarities to the type strains Thalassotalea litorea HMF4135T (97.8 %) and Thalassotalea ponticola GJSW-36T (95.9 %). A whole genome-level comparison of strain ZS-4T with T. litorea MCCC 1K03283T revealed an average nucleotide identity value of 75.6 % and a calculated DNA–DNA hybridization value of 19.6 %. In addition, the genomic DNA G+C content of strain ZS-4T was 45.9 mol%. Thus, based on analyses of its morphology, physiology, fatty acid composition and 16S rRNA gene sequence, strain ZS-4T should be considered a novel species of the genus Thalassotalea , with the proposed name Thalassotalea mangrovi sp. nov. The type strain is ZS-4T (=KCTC 72399T=MCCC 1K03630T).

Estrogen is a steroid hormone produced mainly by the ovaries. It has been found that estrogen could regulate iron metabolism in neurons and astrocytes in different ways. The role of estrogen on iron metabolism in microglia is currently unknown. In this study, we investigated the effect and mechanism of 17β-estrogen (E2) on iron transport proteins. We found that following E2 treatment for 24h in BV2 microglial cell lines, the iron importer divalent metal transporter 1 (DMT1) and iron exporter ferroportin 1 (FPN1) were up-regulated , iron storage protein ferritin (FT) was increased. The protein levels of iron regulatory proteins (IRPs) and hepcidin remained unchanged, but hypoxia inducible factor 1 alpha (HIF-1α) was up-regulated. Two kinds of estrogen receptor β (ERβ) antagonist G15 and G protein estrogen receptor (GPER) antagonist PHTPPcould block the effects of E2 in BV2 microglial cell lines. These results suggest that estrogen could increase the protein expressions of DMT1, FPN1, FT-L and FT-H in BV2 microglia cells, which were not related to the regulation of IRP1 and hepcidin, but to the upregulation of HIF-1α. In addition, estrogen might regulate the expressions of iron-related proteins through both ER β and GPER in BV2 microglia cells.

The efficient use of working memory (WM) increases the potential of a learner’s cognitive abilities in learning through multimedia. The present study aims to explore the role of working memory in vocabulary learning through multimedia input. In particular, we explore the possible associations between two components of WM – executive WM and phonological short-term memory (PSTM) – and the effects of three types of input conditions (Definition + Word information + Video, Definition + Word information, and Definition) on second language (L2) vocabulary learning. A total of 95 students completed learning under the three conditions and took two WM tests: a reading span test, which measures complex executive WM, and a non-word span test, which gauges PSTM. We administered a vocabulary knowledge test, which included receptive and productive vocabulary knowledge, immediately and after two weeks. Our findings, based on repeated-measures analysis of covariance (ANCOVA), support the pronounced effects of the Definition + Word information + Video condition in vocabulary learning and retention, as well as the significant role of complex and phonological WM in vocabulary learning and retention under the three conditions. Theoretical and pedagogical implications concerning the role of WM in vocabulary learning through multimedia input are discussed.

BACKGROUND With the rise of online health care service, there is growing discussion on the relationship between physicians and patients online, yet few researchers have paid attention to patients’ perception of social presence, especially its influence on their willingness to communicate (WTC). OBJECTIVE The goal of the research is to investigate the influence of perceived social presence (PSP) on WTC in mobile medical consultations. METHODS Participants living in Yunnan province during the period of middle to high risk of COVID-19 infection were recruited via the internet. They were assigned randomly into 2 groups interacting with a virtual physician presenting high and low levels of social presence and then asked to complete a questionnaire. Based on the theoretical framework, the study puts forward a model evaluating the relationships among participants’ PSP, communication apprehension (CA), self-perceived communication competence (SPCC), and willingness to communicate about health (WTCH) in the computer-mediated communication between virtual physicians and patients. RESULTS In total 206 (106 in group 1 and 100 in group 2) valid samples were gathered (from 276 log-ins) and 88.8% (183/206) of them were aged 18 to 44 years, which approximately resembles the age distribution of the main population engaging in online medical consultation in China. Independent t test shows that there is significant difference between the PSP of the 2 groups (P=.04), indicating a successful manipulation of social presence. The total effect of PSP on WTCH is 0.56 (PPPPP=.08). CONCLUSIONS This study provides a comprehensible model, demonstrating that PSP is an important antecedent of WTCH, and the sequential mediating effect of CA and SPCC found in this study also proves that in the environment of online mobile medical services, CA cannot affect communication directly. The findings will provide some practical inspiration for the popularization of online medical service, especially for the promotion of online physician-patient communication.

Biliary-stent implantation has become an effective treatment for patients with malignant obstructive jaundice caused by hepatobiliary carcinoma. Stent restenosis due to tumor ingrowth is a common problem. In this study, we assessed a biodegradable form of magnesium (Mg) for its anticancer effect on hepatobiliary carcinoma, compared to the conventional stent material of titanium (Ti). The results showed that a Mg extract inhibited proliferation and induced apoptosis in human cholangiocarcinoma cells, while a Mg plate inhibited cell adhesion and destroyed the cytoskeleton in the process of biodegradation. In animal experiments with H22 tumor-bearing mice, Mg wires implanted in tumors exhibited an inhibitory effect on their growth compared with Ti wires. Fifteen days after implantation of metal wires, the mean tumor volume and weight in the Mg group were significantly smaller than in the Ti group. We observed the dynamic-degradation process of Mg wires in tumors and generation of H

Nortriterpenoids isolated from Walsura cochinchinensis have attracted much attention from both synthetic and medicinal chemists, yet only recently have efficient synthetic approaches to any members appeared. Shown here is that the common intermediate with a 6/6/5/6-fused tetracyclic ring nucleus can be converted to walsucochin family members. The first total syntheses of (±)-walsucochin A, (±)-walsucochinoids C-F, and their analogues were achieved in this work.

A Gram-stain-negative, strictly aerobic and oval-shaped bacterial strain with a flagellum, designated GS-10T, was isolated from mangrove wetland sediment. GS-10T grew at 20–40 °C (optimum, 37 °C), in the pH range of 5.0–11.0 (optimum, 6.0–8.0) and under various NaCl concentrations from 1 to 11 % (w/v) (optimum, 5–6 %). The respiratory quinone was ubiquinone-10, and the predominant polar lipids were phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The major fatty acids (>10 % of the total fatty acids) were summed feature 4 (C17 : 1iso I/anteiso B) and summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The G+C content of the genomic DNA was 63.71 %. On the basis of the results from comparative analysis of the 16S rRNA gene sequence, GS-10T represents a member of the family Rhodobacteraceae and had the highest sequence similarity to Thalassobius gelatinovorus CECT 4357T (97.47 %), followed by Lutimaribacter pacificus W11-2BT (97.03 %), Marivita cryptomonadis CL-SK44T (96.83 %), Thalassobius autumnalis CECT 5118T (96.75 %) and Thalassobius mediterraneus CECT 5383T (96.68 %). Phylogenetic trees based on 16S rRNA gene sequences, multilocus sequence analysis (MLSA) and whole genome sequences revealed that GS-10T clustered with species within the genus Thalassobius . The average nucleotide identity (ANI) and the average amino acid identity (AAI) values were calculated from complete genome sequences and indicated that GS-10T represented a novel species of the genus Thalassobius , and the name Thalassobius mangrovi sp. nov. is proposed for this species. The type strain of Thalassobius mangrovi is GS-10T (=MCCC 1K03624T=KCTC 82131T).

A Gram-stain-negative, strictly aerobic and oval-shaped bacterial strain with a flagellum, designated GS-10