Deep ocean blue holes possess steep physicochemical gradients, especially low dissolved oxygen concentration, which shape the extraordinary microbial communities. However, the environmental responses of microorganisms with different lifestyles and knowledge of culturable microorganisms in the blue holes are still unknown. Here, we investigated the bacterial community structure with different lifestyles of the world’s deepest blue hole - the Yongle Blue Hole (YBH) in the South China Sea using both culture-dependent and -independent methods. YBH can be divided by oxygen content into an oxic zone, a suboxic zone and two anoxic zones. The abundance of bacteria, archaea, genes dsrB and soxB were all higher in the free-living (FL) lifestyle than in the particle-associated (PA) lifestyle, yet the diversity and richness of PA bacteria were higher than that of FL bacteria. More Gammaproteobacteria and less Alphaproteobacteria, Chloroflexi and Nitrospinae were observed within the FL fraction than within the PA fraction. The relative abundance of sulfur-oxidizing bacteria (SOB) was dominant between 100-140 m (anoxic zone I) in YBH, with a maximum of 90.0% (140 m FL fraction). The SOB in YBH were mainly colorless sulfur bacteria and purple non-sulfur bacteria, of which Thiomicrorhabdus and Sulfurimonas were the main representatives. In addition, a total of 294 bacterial strains were isolated on a variety of media and culture conditions, and 22.2% (18/81) of anaerobic strains were identified as potential novel species. Our study reveals a distinction between FL and PA bacteria in YBH. It contributes to further understanding of the bacterial community in deep ocean blue holes, and provides bacterial resources for subsequent studies on their adaptation to extreme marine environments.

Halomonas bacteria are ubiquitous in global marine environments, however, their sulfur-oxidizing abilities and survival adaptations in hydrothermal environments are not well understood. In this study, we characterized the sulfur oxidation ability and metabolic mechanisms of Halomonas titanicae SOB56, which was isolated from the sediment of the Tangyin hydrothermal field in the Southern Okinawa Trough. Physiological characterizations showed that it is a heterotrophic sulfur-oxidizing bacterium that can oxidize thiosulfate to tetrathionate, with the Na2S2O3 degradation reaching 94.86%. Two potential thiosulfate dehydrogenase-related genes, tsdA and tsdB, were identified as encoding key catalytic enzymes, and their expression levels in strain SOB56 were significantly upregulated. Nine of fifteen examined Halomonas genomes possess TsdA- and TsdB-homologous proteins, whose amino acid sequences have two typical Cys-X2-Cys-His heme-binding regions. Moreover, the thiosulfate oxidation process in H. titanicae SOB56 might be regulated by quorum sensing, and autoinducer-2 synthesis protein LuxS was identified in its genome. Regarding the mechanisms underlying adaptation to hydrothermal environment, strain SOB56 was capable of forming biofilms and producing EPS. In addition, genes related to complete flagellum assembly system, various signal transduction histidine kinases, heavy metal transporters, anaerobic respiration, and variable osmotic stress regulation were also identified. Our results shed light on the potential functions of heterotrophic Halomonas bacteria in hydrothermal sulfur cycle and revealed possible adaptations for living at deep-sea hydrothermal fields by H. titanicae SOB56.

A Gram-stain-negative, strictly aerobic, oval-shaped, non-motile bacterium with no flagella, designated strain SCR17T, was isolated from a shrimp gill habitat in Tangyin hydrothermal field of Okinawa Trough. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain SCR17T formed a lineage within the family ‘ Rhodobacteraceae ’, and shared 16S rRNA gene sequence similarity of 93.2–96.2 % to the related genera Aquicoccus and Roseivivax . Strain SCR17T was able to grow with 0–14 % (w/v) NaCl (optimum, 9–10 %). The sole respiratory quinone was ubiquinone-10. The major polar lipids of strain SCR17T comprised phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylethanolamine (PE), an unidentified aminolipid (AL), an unidentified phospholipid (PL) and an unidentified lipid (L). The predominant fatty acids (more than 10 % of the total fatty acids) were C18 : 1ω7c or/and C18 : 1ω6c, anteiso-C15 : 0, C16 : 0 and C19 : 0 cyclo ω8c . The genomic DNA G+C content of strain SCR17T was 67.7 mol%. Based on polyphasic taxonomic analyses, strain SCR17T is considered to represent a novel species in a new genus of the family ‘ Rhodobacteraceae ’, for which the name Carideicomes alvinocaridis gen. nov., sp. nov. is proposed. The type strain of Carideicomes alvinocaridis is SCR17T (=JCM 33426T=MCCC 1K03732T). The discovery of a novel host-associated bacterium in hydrothermal fields provides an opportunity for the study of host–bacterial symbiosis in extreme environments.

冲绳海槽热液区独特的地质环境孕育了特殊的生物群落,硫氧化细菌作为生物地球化学循环的重要参与者在热液生态系统中发挥着至关重要的作用.[目的]通过硫氧化菌株的分离培养揭示冲绳海槽热液区可培养硫氧化细菌的多样性和硫氧化活性.[方法]采用多种培养基对冲绳海槽热液区不同沉积物样品中的硫氧化细菌进行富集培养和分离纯化;利用16S rRNA基因序列确定硫氧化细菌的分类地位并进行系统发育分析;采用碘量法对典型硫氧化菌株硫氧化活性进行检测.[结果]本研究从冲绳海槽热液区样品中共分离鉴定85株硫氧化细菌,分属于α-变形菌纲、γ-变形菌纲、放线菌门和厚壁菌门,优势属为氢弧菌属(Hydrogeno vibrio)、拉布伦氏菌属(Labrenzia)、深海海旋菌属(Thalassospira)和海杆状菌属(Marinobacter).硫氧化活性检测结果表明,7株典型硫氧化菌株对硫代硫酸钠的降解活性介于31％-100％之间,其中泰坦尼克号盐单胞菌SOB56 (Halomonas titanicae SOB56)、南极海杆状菌SOB93(Marinobacter antarcticus SOB93)、印度硫氧化粗杆菌SOB107 (Thioclava indica SOB 107)和嗜温氢弧菌CJG 136 (Hydrogenovibrio thermophiles CJG136)可以完全降解硫代硫酸钠.[结论]冲绳海槽热液区可培养硫氧化细菌的多样性丰富,为研究该热液区的硫循环过程提供了实验材料和理论基础,多种硫氧化活性菌株的获得极大地丰富了菌种资源,为探究深海热液区硫循环的能量代谢途径和分子机制奠定基础.

[Background] Quorum sensing refers to the phenomenon that bacteria use secreted signal molecules to communicate with each other, while quorum quenching refers to inhibiting the quorum sensing pathway by interfering with the production, release, accumulation or response of signal molecules. 田晓荣等: 青岛近海沉积物生物被膜中密度感应及密度感应淬灭细菌多样性 1273 Tel: 010-64807511; E-mail: tongbao@im.ac.cn; http://journals.im.ac.cn/wswxtbcn [Objective] To explore the diversity of quorum sensing and quorum quenching bacteria in sediment biofilm of Qingdao offshore. [Methods] Culturable bacteria were isolated from the sediment biofilm of Qingdao offshore by marine agar 2216E. The bacteria with quorum sensing and quorum quenching activities were screened by plate interaction and high-throughput screening methods. [Results] A total of 83 bacterial strains and 54 bacterial species were isolated, belonging to the four major phyla of bacteria: Proteobacteria, Bacteroidetes, Firmicutes and Actinobacteria. Among them, 38 strains (45.8%) produced acyl-homoserine lactones signal molecules (AHLs), belonging to Proteobacteria (37 strains, 15 species) and Bacteroidetes (1 strain, 1 species). The dominant bacteria belong to the genera Vibrio and Ruegeria. 57 strains (68.7%) can degrade AHLs, including Proteobacteria (41 strains, 23 species), Bacteroidetes (14 strains, 10 species), Firmicutes (5 strains, 5 species) and Actinobacteria (1 strain, 1 species), which showed high abundance and diversity. [Conclusion] The results of this study indicate that among the bacterial isolates from sediments biofilm in Qingdao offshore, quorum sensing and quorum quenching bacteria showed a high abundance and diversity. It laid a foundation for further research and development.

Quorum sensing (QS) is closely associated with the production of multiple virulence factors in bacterial pathogens. N-acyl homoserine lactones (AHLs) are important QS signal molecules that modulate the virulence of gram-negative pathogenic bacteria. Enzymatic degradation of AHLs to interrupt QS, termed quorum quenching (QQ), has been considered a novel strategy for reduction of pathogenicity and prevention of bacterial disease. However, the low expression levels of QQ proteins in the original host bacteria has affected the applications of these proteins. Previously, we identified a novel marine QQ enzyme, named MomL, with high activity and promising biocontrol function. In this study, we linked the target fragment momL to pNCMO2, which provided a basis for the first heterologous expression of MomL in the antifungal and anti-gram-positive-bacteria biocontrol strain Bacillus brevis, and obtaining the recombinant strain named BbMomL. The QQ activity of BbMomL was confirmed using a series of bioassays. BbMomL could not only degrade the exogenous signal molecule C6-HSL, but also the AHL signal molecules produced by the gram-negative pathogens Pectobacterium carotovorum subsp. carotovorum (Pcc) and Pseudomonas aeruginosa PAO1. In addition, BbMomL significantly reduced the secretion of pathogenic factors and the pathogenicity of Pcc and P. aeruginosa PAO1. We tested the biocontrol function of BbMomL for prevention of plant diseases in vitro. The result indicates that BbMomL has a broad antibacterial spectrum. Compared with wild-type B. brevis, BbMomL not only inhibited fungi and gram-positive bacterial pathogens but also considerably inhibited gram-negative bacterial pathogens. Moreover, the Bacillus brevis expression system has good application prospects and is an ideal host for expression and secretion of foreign proteins.

本调查以2017年3381家A股上市公司作为研究对象,对2017年中国上市公司资本效率与财务风险状况进行了全国层面、行业层面、地区层面以及专题调查,研究发现:(1) 2017年中国上市公司总资金管理绩效稳中向好,经营活动资金管理绩效相对于投资活动依旧优势明显,但总资金配置对不同经济活动间的资金管理绩效差异敏感性较差;(2)面对资金面趋紧局势,2017年中国上市公司通过加强生产渠道资金管理,让渡采购渠道资金占用,促使经营活动营运资金管理绩效整体层面保持平稳;(3) 2017年中国上市公司总体财务风险稳定且处于低位,多数行业及三大地区偏好风险规避式财务安排;(4)短期财务风险总体可控,多数行业短期财务风险处于低位,少数行业由于自身营运资金占用较低且周转较快采取了短借长投的融资策略,个别行业受产能过剩影响,出现短借长投现象,短期财务风险较高;(5)东部地区上市公司发展相对成熟,资金效率稳定,财务风险较低,而中、西部地区上市公司资金效率表现出较高的成长性,同时财务风险也较高;(6)通过专题调查发现,产能过剩类企业资金回报率出现跳跃式上涨,但短期财务风险过高,不同经济性质控股公司在资本效率方面差异明显,高杠杆类上市公司财务风险水平有所下降,重资产类上市公司相比轻资产类上市公司在资金管理绩效方面仍存在巨大差距.

Using the data of A-share listed companies in SSE and SZSE from 2008 to 2014,this paper verified the stimulation and trigger mechanism from the earnings management by enterprise R&D,and tried to discuss the adaptive behavior of micro-enterprises to macroeconomic policies in the view of earnings management.We find that the enterprise R&D investment stimulates the enterprise earning management,and the bigger the enterprise earning management is made,the more financial and tax support the enterprises will obtain,and the enterprise with higher R&D investment will have higher degree of sensitivity.We also find that greater R&D intensity has a stronger positive effect on earnings management on governmental subsidy (tax preference).However,the earnings management does not affect the promoting role to the value of the enterprise.

A Gram-stain negative, obligately anaerobic, non-motile, asporogenous long rod-shaped and non-flagellated bacterial strain, designated 4SWWS2-6T, was isolated from sediment in the intertidal zone of Fildes Peninsula, Antarctica. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain 4SWWS2-6T belongs to the genus Ancylomarina and showed high sequence similarity with Ancylomarina subtilis FA102T (96.5%). Optimal growth occurred at pH 6.5, 16 °C and in the presence of 3% (w/v) NaCl. Strain 4SWWS2-6T contained menaquinone-7 (MK-7) as the major respiratory quinone and held iso-C15:0, anteiso-C15:0 and iso-C15:0 3-OH as the major cellular fatty acids. The major polar lipids were phosphatidylethanolamine, phosphatidylmonomethylethanolamine, an aminolipid, two unidentified lipids and an unidentified phospholipid. The DNA G + C content of strain 4SWWS2-6T was 37.6 mol%. On the basis of the polyphasic analyses, strain 4SWWS2-6T is considered to represent a novel species in the genus Ancylomarina, for which the name Ancylomarina psychrotolerans sp. nov. is proposed. The type strain is 4SWWS2-6T (= KCTC 15504T = MCCC 1K01618T).

A Gram-stain-negative, facultative anaerobic, non-motile, short-clavate and non-flagellated marine bacterium strain, designated JC075(T), was isolated from the Yongle Blue Hole in the South China Sea. Based on the 16S rRNA gene sequence, strain JC075(T) was found to be closely related to Marinifilum albidiflavum FB208(T) (97.10 %), Marinifilum flexuosum DSM 21950(T) (96.43 %) and Marinifilum fragile JCM 15579(T) (95.58 %), with less than 90.24% sequence similarity to other genera of the family Marinifilaceae. The growth temperature was in the range of 10-37 degrees C, and the optimum temperature was 16 degrees C. Optimal growth occurred at pH 7.0 and in the presence of 3% (w/v) NaCl. The isoprenoid quinone of strain JC075(T) was identified as menaquinone-7 and the predominant fatty acids (>10 %) were iso-C-15:0 (47.9 %), summed feature 9 (C-17:1 or/and iso-C-17:(1)omega 9c; 18.7 %) and iso-C-17:(0) 3-OH (14.9 %). The major polar lipids were one phosphatidylethanolamine, one phospholipid, one aminophospholipid, one glycolipid, one aminolipid and two unidentified lipids. The DNA G+C content of strain JC075(T) was 35.8 mol%. On the basis of polyphasic analysis, strain JC075(T) was considered to represent a novel species of the genus Marinifilum, for which the name Marinifilum breve sp. nov. is proposed. The type strain is JC075(T) (= KCTC 15646 T = MCCC 1K03477(T) = JCM 32401(T)).

基于沪深两市高新技术A股上市企业2009-2014年的数据,研究了技术创新与企业竞争优势的关系,并从终极产权论的视角考察了不同性质的实际控制人控制下的企业股权混合程度对技术创新与企业竞争优势“关系”的调节作用.研究表明,技术创新与企业竞争优势正相关;考虑股权的二元性时,混合股权中混合程度越高,对技术创新与企业竞争优势正向关系的促进作用越大;但管理层权力过大会抑制混合股权协同作用的发挥.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">本调查以2014年2364家A股上市公司作为研究对象,对中国上市公司营运资金管理进行了行业调查、地区调查和专题调查,得到以下结论:（1）上市公司营运资金配置仍以投资活动为主,但有向经营活动倾斜的趋势;（2）短期金融性负债占比仍较高,上市公司整体财务风险较高;（3）从渠道视角看,中国上市公司营运资金管理绩效持续恶化;（4）从要素视角看,中国上市公司营运资金管理水平较为成熟和稳定;（5）战略新兴产业营运资金越来越依赖营运资本,短期性金融负债占比显著下降,企业财务风险下降,其营运资金管理绩效下降,尤其是营销渠道需要格外重视;（6）国有上市公司与民营上市公司相比,经营活动营运资金管理水平更高,对投资活动投入较大,财务风险较大。</span>

<正>2012年12月1日,由中国会计学会、中国海洋大学等单位共同主办的"2012营运资金管理高峰论坛"在青岛召开,来自政府部门、高等院校、科研院所、企事业单位的150多名专家、学者出席了本次论坛。与会代表紧密结合当前国内外经济形势与企业现实需求,围绕"营运资金管理与财务风险评估"的主题进行了深入的交流与探讨。

The phenomenon that individual investors prefer local stocks and overweight them is called home bias;and it is still a puzzle on the capital market.The individual investors of 3,710 from Shanghai,Tianjin,and Dalian are selected as samples,and based on information advantage,the home bias is tried to explain.The empirical results show that there is home bias inside Chinese stock market and there exists an inverted U-ship relationship between home bias and information advantage.The fact means that there is a critical value involving information advantage,when the information advantage is less than the critical value,the home bias is increasing with information advantage is enhancing;however when information advantage is larger than the critical value,home bias is decreasing with information advantage is enhancing.It is believed that with the strength of information advantage is enhancing,the targets of information are from more to less,the public companies that information involves is from far to near,and it will boost up investors' diversity and is the main reason for the inverted U-ship relationship.

The research analyzes the role of institutional investors in improving corporate governance and constraining earnings management.First,we find,through a game theory model,that the institutional investor is less likely to restrict earnings management when their shares are too small.They will have incentive to monitor earnings management when they have a substantial shareholding.Second,we prove the existence of the invert U-ship by empirical regression with the sample of listed companies in 2004 to 2006 and find 13.07% is the critical shareholding proportion whether institutional investor wants to monitor earnings management.And we also find the earnings management is positively related to the number of institutional shareholders.Monitoring efficiency is decreasing as the number of institutional shareholder is increasing.

文章针对投资者特征与其投资组合中的地缘效应关系问题进行研究.论文以有序分类的logistic模型作为研究方法,选取了上海、天津、大连三个城市8 229个投资者样本,以2005年10月31日为时间点,对投资者特者与其投资组合中的地缘效应关系进行研究.实证研究发现:上海、天津、大连三个城市的投资者具有明显的地缘效应,其中投资者的年龄、累计入市时间、累计投资额、累计投资收益率对地缘效应具有显著影响,年龄大,累计入市时间长,累计投资多,累计投资收益率高的投资者发生地缘效应的概率较高.

In order to improve the scientificity of decision-making for listed companies and investors,taking turnover rate as the measurement criterion of liquidity,45 listed companies involved in the previous two teams of experimental reform of dual-class equity structure were compared in aspects of the exchanging price,the total market value and the liquidity of companies' public trading stocks before and after the reform.The factors influencing the liquidity in the special situation of dual-class equity structure were analyzed.The result shows that,after the reform of dual-class equity structure,the exchanging price falls,and the total market value does not change obviously,then the liquidity is improved;the turnover rate is in negative correlation with the exchanging price,and in positive correlation with the number of public shares.After the share reform,the social interests of different parters maintain the basic stability,and the main reason for liquidity enhancement is the increase in the number of shares;enhancing the liquidity of restricted stock will impact the stock price.

Recognizing the earnings manipulation Correctly is very important for the development of China stock market. Based on the analyses of the motivations and appearances of aggressive earnings manipulation, we design 14 financial indexes initially which hold certain matching relationships and interrelationships among each others. After further screening, we select 5 indexes finally to classify model. We select 35 listed companies which have been punished by China Securities Regulatory Commission as the earnings manipulation samples; and also select 35 healthy listed companies with the same firm size and same industry as the control samples. We establish a classification model of earnings manipulation by using Bayes classifying analysis.

The way how financial constraint affects investment activity has long been a hot issue of the academic world. The present thesis starts from the analysis of influencing factors of financial constraint. It constructs a financial-constraint-measuring system by adopting factor analysis, which has avoided the deviation resulted from the traditional single-index measuring. What's more, it introduces financial constraint into the multiple regression model of investment and analyses the influences financial constraint exerts on investment. Results of the study indicate that investment is restricted by financial constraint.

The present thesis constructs a financial constraint and overconfidence measure. On the basis of classifying the sample by the degree of overconfidence, we explore the influence of financing constrait and overconfidence on investment. It shows (1) Overconfident managers often increase investment and financing constraints inhibites investment; (2) investment-financial constraint sensitivity with overconfident company is smaller than non-overconfident compay and investment-cash flow sensitivity with overconfident company is more than non-overconfident company.