Quantum Light Generation Based on GaN Microring toward Fully On-Chip Source

An integrated quantum light source is increasingly desirable in large-scale quantum information processing. Despite recent remarkable advances, a new material platform is constantly being explored for the fully on-chip integration of quantum light generation, active and passive manipulation, and detection. Here, for the first time, we demonstrate a gallium nitride (GaN) microring based quantum light generation in the telecom C-band, which has potential toward the monolithic integration of quantum light source. In our demonstration, the GaN microring has a free spectral range of 330 GHz and a near-zero anomalous dispersion region of over 100 nm. The generation of energy-time entangled photon pair is demonstrated with a typical raw two-photon interference visibility of 95.5±6.5%, which is further configured to generate a heralded single photon with a typical heralded second-order autocorrelation g_{H}^{(2)}(0) of 0.045±0.001. Our results pave the way for developing a chip-scale quantum photonic circuit.

[Real-world data analysis of 3012 patients undergoing laparoscopic radical gastrectomy in a single center over the past 12 years]

Objective: To Summarize the safety, clinical outcome and technical evolution of laparoscopic gastric cancer surgery. Methods: A retrospective cohort study was carried out. Clinical data of 3012 patients who underwent laparoscopic radical gastrectomy for gastric cancer from January 2010 to March 2022 at Department of General Surgery, the First Affiliated Hospital of Nanjing Medical University were retrospectively collected and analyzed. Case inclusion criteria were gastric malignancies confirmed by pathology, without distant metastasis by examination before operation and exploration during operation, patients undergoing laparoscopic radical gastrectomy, intact function of important organs and with complete data. Exclusion criteria were patients who underwent emergency gastric cancer resection due to gastric bleeding, perforation or obstruction, etc., tumor found to invade adjacent organs such as pancreas or transverse colon during the operation, conversion to open surgery during the operation, those who had other malignant tumors (except thyroid cancer) within 5 years, and those had severe cardiopulmonary, liver, or kidney insufficiency before surgery. Outcomes included: (1) baseline information of patients; (2) trend of the quantity of laparoscopic radical gastrectomy year by year; (3) evolution of the mode of digestive tract reconstruction; (4) periopertive outcome short-term complication was defined as complication occurring within 30 days after operation and classified accordiny to the clavien-Dindo criteria; and (5) 5-year overall survival. SPSS software was used for statistical analysis. Continuous variables that obeyed the normal distribution were expressed in the form of Mean±SD. Days of hospital stay that did not follow a normal distribution were expressed as median (Q₁,Q₃), and the Mann-Whiney U test was used for comparison. Discrete variables were expressed as cases (%), and chi-square test or rank sum test was used for comparison between groups. Linear regression analysis was used to analyze the relationship between the amount of surgery and the year of surgery. Kaplan-Meier method and log-rank test were used for survival analysis. Two-tailed P<0.05 was considered as statistically significant. Results: Among the 3012 cases, 2114 were male and 898 were female. The patients' average age at surgery was (61.1±10.7) years old. According to the number of cumulative cases, the patients were divided into three groups: early, intermediate and late, with 1004 patients in each group. The early group consisted of patients undergoing operation from January 2010 to October 2018, the intermediate group consisted of patients undergoing operation from October 2018 to January 2021, and the late group consisted of patients undergoing operation from January 2021 to March 2022. (1) General information: There were 691 (68.8%), 699 (69.6%) and 724 (72.1%) male patients in early, intermediate and late groups respectively; the average age increased from 56.6 years in 2010 to 62.8 years in March 2022. As for the tumor stage T1, T2, T3, T4, there were 49.0%, 14.4%, 23.9% and 12.6% in the early group; 47.5%, 12.9%, 26.9% and 12.6% in the intermediate group; 39.7%, 14.6%, 30.0%, and 15.6% in the late group, respectively. Patients with N0, N1, N2, N3a, N3b stage were 56.8%, 13.7%, 13.4%, 11.0%, and 5.0% in the early group; 55.7%, 12.9%, 12.8%, 11.6%, and 6.9% in the intermediate group; 51.0%, 16.1%, 12.8%, 12.5%, and 7.5% in the late group, respectively. (2) Year-by-year change in the number of gastric cancer operations: From 19 cases per year in 2010 to 786 per year in 2021, the annual number of gastric cancer operations was proportional to the year of operation (y=47.505x, R²=0.67). The proportion of patients with stage I disease showed a fluctuating downward trend over time, while the proportion of patients with stage III disease increased slightly, accounting for 34% until March 2022. (3) Evolution of digestive tract reconstruction methods: Except in 2010, the digestive tract reconstruction method of distal gastrectomy focused on Billroth-II+Braun anastomosis among patients undergoing laparoscopic gastric cancer surgery in other years, whose proportion had gradually increased from less than 20% in 2016 to about 70% after 2021; the gastrointestinal reconstruction methods after total gastrectomy had gradually increased in π anastomosis and overlap anastomosis since 2016, of which π anastomosis reached about 65% in 2019, and overlap anastomosis reached almost 30% in 2020; the anastomosis methods after proximal gastrectomy had been mainly double-channel anastomosis (54%) and esophagogastric anastomosis (30%) since 2016, and double-channel anastomosis accounted for up to 70% in 2019. (4) Operation time: The operation time of early, intermediate and late group was (193.3±49.8) min, (186.9±44.3) min and (206.7±51.4) min respectively. Intermediate group was significantly shorter than early group (t=3.005, P=0.003), while late group was significantly longer than early group (t=5.875, P<0.001) and intermediate group (t=9.180, P<0.001). (5) Postoperative hospital stay: The median length of hospital stay for gastric cancer patients in early, intermediate and late groups was 9 (8, 11) d, 8 (7, 10) d, and 8 (7.5, 10) d respectively. The postoperative hospital stay of intermediate group and late group was significantly shorter than that of early group (Z=-12.467, Z=-5.981, both P<0.001), but there was no significant difference between intermediate group and late group (Z=0.415,P=0.678). (6) Postoperative complication: The morbidity of short-term complication in early, intermediate and late group was 20.4% (205/1004), 16.2% (163/1004), and 16.2% (162/1004) respectively, and above morbidity of intermediate group and late group was significantly lower than that of early group (χ²=5.869, P=0.015; χ²=6.165, P=0.013), while there was no significant difference between intermediate group and late group (χ²=0.004,P=0.952). The morbidity of short-term complication of grade IIIor higher was 8.0% (80/1004), 7.6% (76/1004), and 4.9% (49/1004) in early, intermediate and late group respectively, and above morbidity of late group was significantly lower than that of early and intermediate group (χ²=7.965, P=0.005; χ²=6.219,P=0.013), while there was no significant difference between intermediate group and early group (χ²=0.111,P=0.739). (7) Survival analysis: The follow-up deadline for survival data was December 31, 2021, and the median follow-up time was 29.5 months. The overall 5-year survival rate of all the patients was 74.7%. The 5-year survival rates of stage I, II and III patients were 92.0%, 77.2%, and 40.3% respectively and 5-year survival rates of patients with stage IA, IB, IIA, IIB, IIIA, IIIB and IIIC were 93.2%, 87.8%, 81.1%, 72.7%, 46.2%, 37.1%, and 34.0% respectively. Conclusions: The number of laparoscopic gastric cancer operation in our center is increasing year by year. With the maturity of laparoscopic technology, the morbidity of complication in laparoscopic gastric cancer surgery is decreasing.

Evidence for the association of triatomic molecules in ultracold 23Na40K + 40K mixtures

Ultracold assembly of diatomic molecules has enabled great advances in controlled chemistry, ultracold chemical physics and quantum simulation with molecules^1-3. Extending the ultracold association to triatomic molecules will offer many new research opportunities and challenges in these fields. A possible approach is to form triatomic molecules in a mixture of ultracold atoms and diatomic molecules by using a Feshbach resonance between them^4,5. Although ultracold atom-diatomic-molecule Feshbach resonances have been observed recently^6,7, using these resonances to form triatomic molecules remains challenging. Here we report on evidence of the association of triatomic molecules near the Feshbach resonance between ²³Na⁴⁰K molecules in the rovibrational ground state and ⁴⁰K atoms. We apply a radio-frequency pulse to drive the free-bound transition in ultracold mixtures of ²³Na⁴⁰K and ⁴⁰K and monitor the loss of ²³Na⁴⁰K molecules. The association of triatomic molecules manifests itself as an additional loss feature in the radio-frequency spectra, which can be distinguished from the atomic loss feature. The observation that the distance between the association feature and the atomic transition changes with the magnetic field provides strong evidence for the formation of triatomic molecules. The binding energy of the triatomic molecules is estimated from the measurements. Our work contributes to the understanding of the complex ultracold atom-molecule Feshbach resonances and may open up an avenue towards the preparation and control of ultracold triatomic molecules.

Marinisubtilis pacificus gen. nov., sp. nov., a Member of the Family Microbacteriaceae Isolated From a Deep-Sea Seamount

A Gram-stain-positive, yellow, aerobic, slender rod-shaped bacterial strain, designated KN1116^T, was isolated from a deep-sea seamount. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain KN1116^T was related to the genus Chryseoglobus and had highest 16S rRNA gene sequence identity with Chryseoglobus frigidaquae CW1^T (98.5%). The predominant cellular fatty acids were anteiso-C_15:0 and iso-C_16:0. The quinone system for strain KN1116^T comprised menaquinone MK-12, MK-11, MK-10 and MK-13. The polar lipid profile contained diphosphatidylglycerol, phosphatidylglycerol, six unknown glycolipids, two unidentified phospholipids and one unknown polar lipid. The cell-wall peptidoglycan of strain KN1116^T was of the type B1β, containing 2,4-diaminobutyric acid as the diamino acid. Genome sequencing revealed the strain KN1116^T has a genome size of 2.7 Mbp and a G+C content of 69.4 mol%. Based on phenotypic, chemotaxonomic, phylogenetic and genomic data, strain KN1116^T represents a novel species of a novel genus of the family Microbacteriaceae, for which the name Marinisubtilis pacificus gen. nov., sp. nov. is proposed. The type strain of Marinisubtilis pacificus is KN1116^T (=CGMCC 1.17143^T =KCTC 49299^T).

Pelagihabitans pacificus gen. nov., sp. nov., a member of the family Flavobacteriaceae isolated from a deep-sea seamount

The Gram-stain-negative, orange-pigmented, non-spore-forming, non-motile, strictly aerobic, rod-shaped bacterial strain, designated TP-CH-4^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. The optimal growth conditions were determined to be at pH 7-8, 25-30 °C and in the presence of 2 % (w/v) NaCl. The major respiratory quinone was MK-6. The polar lipid profile contained phosphatidylethanolamine, two unidentified aminolipids, two unidentified phospholipids and three unidentified polar lipids. The predominant cellular fatty acids were iso-C_15 : 0 and summed feature 1 (composed of C_13 : 03-OH and/or iso-C_15 : 1H). Phylogenetic analysis of 16S rRNA gene sequences revealed that strain TP-CH-4^T was a member of the family Flavobacteriaceae and formed a distinct lineage. Strain TP-CH-4^T displayed highest sequence similarities to Pseudozobellia thermophila KMM 3531^T (95.1 %) and Flagellimonas flava A11^T (93.9 %). Genome sequencing revealed the strain TP-CH-4^T has a genome size of 4.5 Mbp and a G+C content of 44.5 mol%. Collectively, based on phenotypic, chemotaxonomic, phylogenetic and genomic evidence, strain TP-CH-4^T represents a novel species of a novel genus of the family Flavobacteriaceae, for which the name Pelagihabitans pacificus gen. nov., sp. nov. is proposed. The type strain of Pelagihabitans pacificus is TP-CH-4^T (=CGMCC 1.17120^T=KCTC 72434^T).

Flavobacterium profundi sp. nov., isolated from a deep-sea seamount

The Gram-stain-negative, rod-shaped, facultative anaerobic, motile bacterial strain, designated TP390^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain TP390^T was related to the genus Flavobacterium and had highest 16S rRNA gene sequence identity with the type strain of Flavobacterium jejuense EC11^T (97.8 %). Sequence similarities to all other type strains of current species of the genus Flavobacterium were below 97 %. The predominant cellular fatty acids were iso-C_15 : 0 and iso-C_15 : 1G. The quinone system for strain TP390^T comprised predominantly menaquinone MK-6 and the polar lipid profile contained phosphatidylethanolamine, four unknown aminolipids, one glycolipid and six unknown polar lipids. The genomic DNA G+C content of strain TP390^T was 31.2 mol%. In addition, the maximum values of in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) between strain TP390^T with F. jejuense KCTC 42149^T were 22.60 and 80.01% respectively. Combined data from phenotypic, phylogenetic, isDDH and ANI data demonstrated that the strain TP390^T is representative of a novel species of the genus Flavobacterium, for which we propose the name Flavobacterium profundi sp. nov. (type strain TP390^T=KACC 18559^T=CGMCC 1.15398^T).

Aequorivita sinensis sp. nov., isolated from sediment of the East China Sea, and reclassification of Vitellibacter todarodis as Aequorivita todarodis comb. nov. and Vitellibacter aquimaris as Aequorivita aquimaris comb. nov

The Gram-strain-negative, rod-shaped, facultatively anaerobic, non-motile bacterial strain, designated S1-10^T, was isolated from marine sediment. Strain S1-10^T grew at 4-42 °C (optimally at 30-35 °C), at pH 7.0-10 (optimally at pH 9) and in the presence of 0.5-8 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain S1-10^T was related to the genus Aequorivita and had highest 16S rRNA gene sequence similarity to Aequorivita viscosa 8-1b^T (97.7%). The predominant cellular fatty acids were iso-C_15 : 0 and anteiso-C_15 : 0. The main respiratory quinone was menaquinone 6 (MK-6). The genomic DNA G+C content of strain S1-10^T was 34.6 mol%. The polar lipid profile of strain S1-10^T contained phosphatidylethanolamine, two aminolipids, two glycolipids, one phosphoglycolipid and three unidentified polar lipids. In addition, the maximum values of in silico DNA-DNA hybridization (isDDH) and average nucleotide identity (ANI) between strain S1-10^T and A. viscosa CGMCC 1.11023^T were 15.4 and 75.7 %, respectively. Combined data from phenotypic, phylogenetic, isDDH and ANI analyses demonstrated that strain S1-10^T is the representative of a novel species of the genus Aequorivita, for which we propose the name Aequorivita sinensis sp. nov. (type strain S1-10^T=CGMCC 1.12579^T=JCM 19789^T). We also propose that Vitellibacter todarodis and Vitellibacter aquimaris should be transferred into genus Aequorivita and be named Aequorivita todarodis comb. nov. and Aequorivita aquimaris comb. nov., respectively. The type strain of Aequorivita todarodis comb. nov. is MYP2-2^T (= KCTC 62141^T= NBRC 113025^T) and the type strain of Aequorivita aquimaris comb. nov. is D-24^T (=KCTC 42708^T=DSM 101732^T).

Algibacter pacificus sp. nov., isolated from a deep-sea seamount

The Gram-stain-negative, rod-shaped, yellow-pigmented and facultative anaerobic bacterial strain, designated H164T, was isolated from seawater collected from the Caroline Seamounts in the Pacific Ocean. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain H164T was related to the genus Algibacter and had highest 16S rRNA gene sequence similarity to Algibacter wandonensis WS-MY22T (97.4 %). The major cellular fatty acids were iso-C15 : 0, anteiso-C15 : 0, iso-C15 : 1 G, iso-C15 : 0 3-OH and iso-C17 : 0 3-OH. The predominant menaquinone was MK-6. The polar lipid profile contained phosphatidylethanolamine, one unidentified aminolipid and two unidentified lipids. The genomic DNA G+C content of strain H164T was 33.2 mol%. The values of in silico DNA–DNA hybridization (isDDH) and average nucleotide identity (ANI) between strain H164T and A. wandonensis KCTC 32381T were 26.10 and 81.88 %. The isDDH and ANI values between strain H164T and Algibacter lectus DSM 15365T were 25.40 and 81.79 %. Combined data from phenotypic, phylogenetic, isDDH and ANI analyses demonstrated that strain H164T represents a novel species of the genus Algibacter , for which we propose the name Algibacter pacificus sp. nov. (type strain H164T=KCTC 72432T=CGMCC 1.17117T).

Observation of Interference between Resonant and Detuned stirap in the Adiabatic Creation of ^{23}Na^{40}K Molecules

Stimulated Raman adiabatic passage (stirap) allows efficiently transferring the populations between two discrete quantum states and has been used to prepare molecules in their rovibrational ground state. In realistic molecules, a well-resolved intermediate state is usually selected to implement the resonant stirap. Because of the complex molecular level structures, the detuned stirap always coexists with the resonant stirap and may cause unexpected interference phenomenon. However, it is generally accepted that the detuned stirap can be neglected if compared with the resonant stirap. Here we report on the first observation of interference between the resonant and detuned stirap in the adiabatic creation of ^{23}Na^{40}K ground-state molecules. The interference is identified by observing that the number of Feshbach molecules after a round-trip stirap oscillates as a function of the hold time, with a visibility of about 90%. This occurs even if the intermediate excited states are well resolved, and the single-photon detuning of the detuned stirap is about 1 order of magnitude larger than the linewidth of the excited state and the Rabi frequencies of the stirap lasers. Moreover, the observed interference indicates that if more than one hyperfine level of the ground state is populated, the stirap prepares a coherent superposition state among them, but not an incoherent mixed state. Further, the purity of the hyperfine levels of the created ground state can be quantitatively determined by the visibility of the oscillation.

[Qualitative study on unprotected sexual behaviors among male students who have sex with men in Beijing]

Objective: To investigate the related factors of unprotected sexual behaviors among male students who have sex with men in Beijing. Methods: Male students who have sex with men were recruited from May 2018 to July 2018 at two voluntary counseling and testing (VCT) clinics in Beijing by convenient sampling method. Information being collected during in-depth personal interviews with a semi-structured outline included ways to seek sexual partners, sexual partners characteristics, attitude of condom use, incidence and causes of unprotected sexual behaviors, rush poppers and alcohol use. The text information was summarized and analyzed by Nvivo 11.0 software. Results: A total of 35 male students who have sex with men were recruited and interviewed, the median of age was 22 years old (P(25)-P(75): 21-24 years old). We found that incomprehensive knowledge of condom use, low risk perception of non-anal sexual behaviors, rush poppers and alcohol use were risk factors of unprotected sexual behaviors on individual level. Besides, sex with regular sex partners, partners who were much older or not from campus, and insertive partners are more likely to be unprotected. Furthermore, refusal of condom use by sexual partners and low self-efficacy of decision-making on condom use were the main reasons for unprotected sexual behaviors among male student who have sex with men. Conclusion: Lack of condom use knowledge, low risk perception of non-anal sexual behaviors and insufficient ability to refuse non-condom requirements for regular sex partners, partners who were much older or not from campus, and insertive partners are related factors of unprotected sexual behaviors among male students who have sex with men.

[Effects of ICAT silencing in Wnt signaling pathway and NSC67657 induced cell differentiation of HL-60 cells]

目的

探讨β-catenin相关蛋白1（ICAT）沉默对Wnt信号通路及甾醇类新药NSC67657诱导HL-60细胞单核系分化的影响。

方法

NSC67657诱导HL-60细胞分化，流式细胞术检测细胞表面分化抗原CD14的表达，检测细胞分化程度；构建慢病毒LV-ICAT-RNAi载体，感染HL-60细胞，采用荧光实时定量PCR和Western blot技术检测感染前后ICAT基因和蛋白表达情况，判断干扰效果；采用免疫共沉淀技术检测β-catenin与ICAT蛋白在细胞内的相互作用；采用Western blot技术分析NSC67657诱导非感染HL-60细胞（HL-60v组）和LV-ICAT-RNAi载体感染HL-60细胞（HL-60i组）前后Wnt/β-catenin通路下游靶点Cyclin D1、TCF-1和c-Jun的表达情况；NSC67657分别作用HL-60v组和HL-60i组细胞24 h，采用瑞氏染色、透射电子显微镜、流式细胞术观察细胞分化情况。

结果

10 µmol/L NSC67657可以诱导HL-60细胞向单核系分化，连续诱导5 d后，CD14⁺细胞比例为（92.30±5.14）%；HL-60i细胞ICAT mRNA表达（0.07±0.01）明显低于HL-60v组（1.00±0.08）（P=0.002）（平均敲减效率为93.2%），Western blot结果与PCR结果一致（P=0.001）；免疫共沉淀结果显示，ICAT与β-catenin蛋白在细胞分化前后都存在相互作用，药物诱导细胞分化后两者相互作用条带吸光度明显增加。药物作用HL-60i细胞Wnt信号通路下游靶蛋白Cyclin D1、TCF-1和c-Jun表达明显高于HL-60v组，但低于非药物处理组。NSC67657作用HL-60i细胞CD14⁺细胞比例为（8.33±3.14）%，明显低于HL-60v组的（19.08±4.73）%，但仍高于非药物处理非感染HL-60细胞组（0.60±0.03）%（F=119.24，P=0.010），细胞形态和超微结果符合细胞表面分化抗原检测结论。

结论

ICAT蛋白参与了NSC67657诱导HL-60细胞的单核系分化，Wnt/β-catenin信号通路可能起到桥梁作用。

Observation of magnetically tunable Feshbach resonances in ultracold 23Na40K + 40K collisions

Resonances in ultracold collisions involving heavy molecules are difficult to simulate theoretically and have proven challenging to detect. Here we report the observation of magnetically tunable Feshbach resonances in ultracold collisions between potassium-40 (40K) atoms and sodium-23–potassium-40 (23Na40K) molecules in the rovibrational ground state. We prepare the atoms and molecules in various hyperfine levels of their ground states and observe the loss of molecules as a function of the magnetic field. The atom-molecule Feshbach resonances are identified by observing an enhancement of the loss. We have observed 11 resonances in the magnetic field range of 43 to 120 gauss. The observed atom-molecule Feshbach resonances at ultralow temperatures probe the three-body potential energy surface with exceptional resolution and will help to improve understanding of ultracold collisions.

Simple method for liquid analysis by laser-induced breakdown spectroscopy (LIBS)

As a fast-developing technique for in situ multi-element analysis method, laser induced breakdown spectroscopy - LIBS is, however, developing slowly on liquid analysis due to some technical difficulties. We propose a new method, namely capillary mode, to quantify the concentrations of the elements in solution using LIBS. A Nd:YAG laser with repetition of 10 Hz were used to analyze the solution of Na₂CrO₄ and no any sample preparation in measurements. The experimental results show that the splashing of liquid induced by laser pulses is decreased significantly and the pollution of mirrors is avoided effectively using liquid capillary mode. The results of quantitative analysis for liquid are also improved than other method. The calibration curves of Cr and Na are well characterized by straight lines and the regression coefficient values of the linear fit are better than 0.998. The limits of detection (LODs) of Cr and Na are determined to be 28.9 mg/L and 1.0 mg/L in this work, respectively. The experimental results show that the liquid capillary mode provides a more practical and very simple approach to improve accuracy of quantitative element analysis in liquids by LIBS technique.

Solimicrobium silvestre gen. nov., sp. nov., isolated from alpine forest soil

A Gram-stain-negative, rod-shaped, motile, catalase and cytochrome c oxidase-positive bacterial strain, designated S20-91^T, was isolated from alpine forest soil. Growth occurred within a temperature range of 0-25 °C. Yeast extract was required for growth. Phylogenetic analysis based on 16S rRNA gene sequencing showed that strain S20-91^T was related to the genus Herminiimonas and had the highest 16S rRNA gene sequence similarity to Herminiimonas arsenicoxydans ULPAs1^T (96.5 %). The strain contained ubiquinone 8 as the predominant respiratory quinone and phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as the major polar lipids. The major cellular fatty acids (>10 %) were C16 : 1ω7c (55.3 %) and C16 : 0 (25.6 %). The genomic DNA G+C content was 47.6 mol%. Combined data of genomic, phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strain S20-91^T represents a novel genus and species, for which the name Solimicrobium silvestre gen. nov., sp. nov. is proposed. The type strain is S20-91^T (=DSM 104733^T=LMG 30010).

Microstructures and mechanical properties of in situ TiC-β-Ti-Nb composites with ultrafine grains fabricated by high-pressure sintering

In this study, an in situ β–Ti–Nb composites reinforced with TiC particles with an ultrafine grain size were fabricated using a powder metallurgical (PM) method. The microstructures and mechanical properties of the composites were characterized using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and compression tests. TiC particles were formed in the ball-milled powders after annealing at 600 °C due to a chemical reaction between stearic acid and titanium. Using high-pressure sintering (HPS) on an apparatus with six tungsten carbide anvils, a fully dense β–Ti–Nb composite reinforced with fine in situ TiC particles was obtained. The TiC particles exhibit particle sizes of ~500 nm, uniformly distributed in the composite matrix, which had grain sizes of ~600 nm. Thus, the TiC–β–Ti–Nb composite show very high compression yield strength and relatively high plasticity contributed by grain refinement and TiC particles strengthening. The composite with 45 vol.% TiC exhibited excellent mechanical properties, with a yield compressive strength of 1990 MPa and plastic strain of 9.12%. More over, a modified rule-of-mixture (ROM) was presented to describe the combined strengthening effect of grain refinement and TiC particles.

Mesoflavibacter profundi sp. nov. Isolated from a Deep-Sea Seamount

The Gram-stain-negative, rod-shaped, aerobic strain, designated YC1039^T, was isolated from a seamount northern Mariana Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain YC1039^T was related to the genus Mesoflavibacter and had highest 16S rRNA gene sequence similarities to Mesoflavibacter sabulilitoris GJMS-9^T (98.3%) and Mesoflavibacter zeaxanthinifaciens TD-ZX30^T (98.2%). The predominant cellular fatty acids were iso-C_15:1 G and iso-C_15:0. The polar lipid profile contained phosphatidylethanolamine, two unidentified phospholipids, and 13 unidentified lipids. The respiratory quinone was MK-6. The genomic DNA G+C content of strain YC1039^T was 29.8 mol%. On the basis of the evidence presented in this study, strain YC1039^T represents a novel species of the genus Mesoflavibacter, for which we propose the name Mesoflavibacter profundi sp. nov. (type strain YC1039^T = KACC 19026^T = CGMCC 1.16329^T).

Ponticaulis profundi sp. nov. isolated from a deep-sea seamount

A Gram-stain negative, rod-shaped, strictly aerobic, motile bacterial strain, designated YC239^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain YC239^T is related to the genus Ponticaulis and has high 16S rRNA gene sequence similarity with the type strain of Ponticaulis koreensis GSW-23^T (97.9%). The predominant cellular fatty acids were C_18:1ω7c, C_16:0, C_17:0 and C_17:1ω6c. Strain YC239^T had Q-10 as the predominant ubiquinone. The polar lipid profile contained phosphatidylglycerol, two unidentified aminolipids and six unidentified polar lipids. The genomic DNA G+C content of strain YC239^T was 52.8 mol%. Strain YC239^T shared DNA relatedness of 38% with Ponticaulis koreensis KCTC 22146^T. On the basis of the evidence presented in this study, strain YC239^T represents a novel species of the genus Ponticaulis, for which we propose the name Ponticaulis profundi sp. nov. (type strain YC239^T = KACC 19027^T = CGMCC 1.15741^T).

Rheinheimera marina sp. nov., isolated from a deep-sea seamount

A bacterial strain designated TP462^T, isolated from a seamount near the Yap Trench in the tropical western Pacific, was characterized using a polyphasic taxonomic approach. Strain TP462^T was found to be Gram-stain-negative, aerobic, rod-shaped and motile by means of a single polar flagellum. Growth occurred at 4-37 °C (optimum, 25-30 °C) and with 0-4.0 % NaCl (optimum, 2-3 %). Phylogenetic analysis based on 16S rRNA gene sequence showed that strain TP462^T was related to the genus Rheinheimera and had the highest 16S rRNA gene sequence similarity with the type strain Rheinheimera tangshanensis JA3-B52^T (96.8 %). The predominant cellular fatty acids were C17 : 1ω8c, summed feature 3 (composed of iso-C15 : 0 2-OH and/or C16 : 1ω7c) and C16 : 0. The polar lipid profile contained phosphatidylglycerol, phosphatidylethanolamine and two unidentified lipids. The genomic DNA G+C content of strain TP462^T was 48.7 mol%. On the basis of the evidence presented in this study, strain TP462^T represents a novel species of the genus Rheinheimera, for which we propose the name Rheinheimera marina sp. nov. (type strain TP462^T=KACC 18560^T=CGMCC 1.15399^T).

Maribacter marinus sp. nov. isolated from a deep-sea seamount

A Gram-stain negative, rod-shaped, aerobic strain, designated YC973^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. Phylogenetic analysis based on its 16S rRNA gene sequence showed that strain YC973^T is related to the genus Maribacter and has high 16S rRNA gene sequence similarity to Maribacter orientalis KMM 3947^T (97.6%). The predominant cellular fatty acids were iso-C_15:0, iso-C_15:1 G and an unidentified fatty acid of equivalent chain-length 13.565. The polar lipid profile contained phosphatidylethanolamine and five unidentified lipids. The genomic DNA G+C content of strain YC973^T was 36.1 mol%. On the basis of the evidence presented in this study, strain YC973^T represents a novel species of the genus Maribacter, for which we propose the name Maribacter marinus sp. nov. (type strain YC973^T = KACC 19025^T = CGMCC 1.16328^T).

Thalassotaleaprofundi sp. nov. isolated from a deep-sea seamount

The Gram-stain-negative, rod-shaped, strictly aerobic, motile bacterial strain, designated YM155^T, was isolated from a seamount near the Yap Trench in the tropical western Pacific. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain YM155^T was related to the genus Thalassotalea and had highest 16S rRNA gene sequence similarities with the type strains of Thalassotalea piscium T202^T (97.2 %) and Thalassotalea agariperforans M-M1^T (97.2 %). The predominant cellular fatty acids were C17 : 1ω8c, summed feature 3 (composed of iso-C15 : 0 2-OH and/or C16 : 1ω7c) and iso-C16 : 0. Ubiquinone 8 (Q-8) was the respiratory quinone. The polar lipid profile contained phosphatidylglycerol, phosphatidylethanolamine, two unidentified phospholipids and one unidentified lipid. The genomic DNA G+C content of strain YM155^T was 36.1 mol%. On the basis of the evidence presented in this study, strain YM155^T represents a novel species of the genus Thalassotalea, for which we propose the name Thalassotalea profundi sp. nov. (type strain YM155^T=KACC 18563^T=CGMCC 1.15922^T).