Studies on hybridization effects of different geographic populations of Chlamys farreri Ⅱ.The medium-term growth and development of Chlamys farreri populations from China and Russia and their reciprocal crosses

Based on the research of juvenile (2, 3, 4 months) growth and survival of three populations of two different geographic areas in Chlamys farreri from Russian and China and their F1 hybrids derived from Chinese cultural population (CC) (?) × Russian population (RW) (?) , Chinese wild population (CW) (?) × Russian population (RW) (?), Russian population (RW) (?) × Chinese wild population (CW) (?) , the study of the medium-term (6, 8, 10, 12 months) growth and development of Chlamys farreri was carried out. The four determined results indicated that there existed different extent heterosis (3% -52%) for the growth in three types of F1 hybrids, and the offspring derived from CC(?) ×R(?) had a stronger heterosis among the crosses at the medium-term; the uptrend among traits are wet weight >shell width>shell length> shell height, Chinese cultural population could be recognized as excellent parent, and seasonal variations influence very much on the daily increment and growth rate of each trait of Chlamys farreri and it is only able to survive and could barely grow in winter (6-8 months), but grows fast in temperate season (10-12 months).

A Novel Lifecycle Model for Web-based Application Development in Small and Medium Enterprises

Software engineering＇s lifecycle models havc proven to be very important for traditional software development. However, can these models be applied to the development of Web-based applications as well？ In recent years, Web-based applications have become more and more complicated and a lot of efforts have been placed on introducing new technologies such as J2EE, PhP, and .NET, etc., which have been universally accepted as the development technologies for Web-based applications. However, there is no universally accepted process model for the development of Web-based applications. Moreover, shaping the process model for small medium-sized enterprises （SMEs）, which have limited resources, has been relatively neglected. Based on our previous work, this paper presents an expanded lifecycle process model for the development of Web-based applications in SMEs. It consists of three sets of processes, i.e., requirement processes, development processes, and evolution processes. Particularly, the post-delivery evolution processes are important to SMEs to develop and maintain quality web applications with limited resources and time.

The Importance of Small and Medium Enterprise Development for Efficient Global Market Environment

Small and medium enterprises(SMEs)play an important role in the world economy.Modern trends in the development of small and medium enterprises imply a constant increase in their role in the total income of an economy.For such an approach,it is important to achieve quality organizational and managerial concepts of planning strategy development.In many countries,small businesses dominate in the production of a number of smaller products,higher consumption,and high quality of these products.The concept of a small economy consists of a group of companies that stand out in terms of their characteristics in relation to large companies.In relation to large companies as business systems,SMEs differ based on the concept of their own organization’s business,the volume of business,and the availability of resources.Research data show that the main obstacle to efficient continuous business of SMEs in the world is the procurement and maintenance of business resources.Ensuring continuity in production is often a problem of lack of resources,which primarily characterizes them in relation to large companies.Small business and entrepreneurship are the main backbone of today’s economic development,viewed globally.The purpose of the development of small and medium enterprises in the world is to enable the development of a successful and flexible entrepreneurial climate as an important organizational determinant,which is a prerequisite for progress in the modern world economy.The feature of SME development is the innovation of employees that needs to be constantly developed.In that way,conditions are provided for technological development,formation of flexible organizations,and new employment.In practice,small and medium enterprises are the engine of economic development.It is a sector that promotes private property and entrepreneurial skills.According to experts on economic issues,SMEs are today and in the future,not only in Serbia,the Region,but also in the world,a synonym for the private sector-for entrepreneurship.Comparative analysis shows the advantage of SMEs,especially in flexible business,where they can quickly adapt to change and can fully meet market demands.

TEMPERATURE PROFILES OF LOCAL THERMAL NONEQUILIBRIUM FOR THERMAL DEVELOPING FORCED CONVECTION IN POROUS MEDIUM PARALLEL PLATE CHANNEL

Based on the two-energy equation model, taking into account viscous dissipation due to the interaction between solid skeleton and pore fluid flow, temperature expressions of the solid skeleton and pore fluid flow are obtained analytically for the thermally developing forced convection in a saturated porous medium parallel plate channel, with walls being at constant temperature. It is proved that the temperatures of the two phases for the local thermal nonequilibrium approach to the temperature derived from the one-energy equation model for the local thermal equilibrium when the heat exchange coefficient goes to infinite. The temperature profiles are shown in figures for different dimensionless parameters and the effects of the parameters on the local thermal nonequilibrium are revealed by parameter study.

Problems of private industrial economic development and its countermeasures for Zigong City,Sichuan Province,China

The differences of regional economic development between underdeveloped areas and developed areas are mainly embodied by different levels of private economic development. Since 20-year reform and opening-up to the outside world, the private industry of Zigong has developed gradually, become more and more economically competitive, and played a more and more important role in the economic structure of Zigong. This paper analyzes the problems of private economy and its countermeasures based on the research on its status quo.

Coupling and Long-term Change Characteristics of Forest Carbon Sink and Forestry Economic Development in China

[Objectives]To analyze the changes in of forest carbon sink and forestry economic development,provide reference for relevant management decisions,ecological governance and resource and environment management,and promote the development of green low-carbon economy in China.[Methods]Based on the data of six forest resource inventories from 1989 to 2018 and related studies,the comprehensive evaluation model of forest carbon sink and forestry economic development,the coupling degree model of forest carbon sink and forestry economic development,and the coupling coordination degree model of forest carbon sink and forestry economic development were adopted.The coupling degree of forest carbon sink and forestry economic development from 1992 to 2018 was analyzed.Stepwise regression and ARIMA model were used to analyze the influencing factors and lagging characteristics of forest carbon sink.The coupling degree between forest carbon sink and forestry economic development in China from 2019 to 2030 was predicted by autoregression and ADF test.The coupling between forest carbon sink and forestry economic development in China and its long-term change characteristics were also discussed in this study.[Results](i)The investment of ecological construction and protection,the actual investment of forestry key ecological projects,GDP and the import of forest products had a significant impact on forest resources carbon stock.The total output value of forestry industry,the actually completed investment of forestry key ecological projects and the export volume of forest products had a significant impact on the forest carbon sink,and the actually completed investment of forestry key ecological projects has the greatest impact on the two.(ii)The impact of actually completed investment of forestry key ecological projects had a lag of 2 years on the forest resources carbon stock and a lag of 1 year on the forest carbon sink.When investing in forest carbon sink,it is necessary to make a good plan in advance,and do a good job in forest resources management and time optimization.(iii)From 1992 to 2018,the coupling degree of forest resources carbon stock,forest carbon sink and long-term development of forestry economy in China was gradually increasing.Although there were some fluctuations in the middle time,the coupling degree of forest resources carbon stock and the long-term development of forestry economy increased by 9.24%annually,and the degree of coupling coordination increased from"serious imbalance"in 1992 to"high-quality coordination"in 2018.From 1993 to 2018,the coupling degree of forest carbon sink and long-term development of forestry economy increased by 9.63%annually,slightly faster than the coupling coordination degree of forest resources carbon stock and long-term development of forestry economy.The coordination level also rose from level 2 in 1993 to level 10 in 2018.(iv)The prediction shows that the coupling coordination degree of forest resources carbon stock,forest carbon sink and the long-term development of forestry economy would increase from 2019 to 2030.The coupling coordination degree(D)values of both were close to 1,the coordination level was also 10 for a long time,and the degree of coupling coordination was also maintained at the"high-quality coordination"level for a long time.[Conclusions]Forest has multiple benefits of society,economy and ecology,and forest carbon sink is only a benefit output.The long-term coupling analysis of forest carbon sink and forestry economic development is a key point to multiple benefit analysis.The analysis shows that the spillover effect and co-evolution effect of forest carbon sink in China are significant.From 1992 to 2018,the coupling coordination degree of forest carbon sink and forestry economic development was gradually rising.The prediction analysis also indicate that the coupling coordination degree between the forest carbon sink and the long-term development of forestry economy will remain at the level of"high-quality coordination"for a long time from 2019 to 2030.Therefore,improving the level of forest management and maintaining the current trend of increasing forest resources are the key to achieving the goal of carbon peaking and carbon neutrality in China.

数字经济与中小企业生存:促进或抑制?

数字经济发展浪潮下,促进中小企业生存是中国经济高质量发展的重要路径。本文在理论分析基础上,结合采用因子分析法构建的2014—2021年城市数字经济发展指数和中小企业生存能力指数,实证检验了数字经济对中小企业生存的影响及其机制。研究发现,数字经济发展对中小企业生存具有显著的正向作用。这一结论在进行多种稳健性检验后仍成立。机制分析发现,数字经济发展具有融资约束缓解效应和代理成本节约效应,即数字经济通过优化中小企业自身融资能力和外部融资环境缓解融资约束,通过减少信息不对称和管理者决策过程中的非理性降低代理成本,进而促进中小企业生存。异质性分析发现,数字经济发展对东中部地区、制造业和管理效率高的中小企业的正向促进作用更显著。

女性中层管理者职业继续发展阻碍因素的探索研究

为定位“玻璃天花板”的最关键因素及特殊阶段呈现的重要因素,文章聚焦“分水岭”阶段的女性中层管理者群体,构建女性职业发展阻碍因素的理论模型。结果表明,影响女性中层管理者职业继续发展的因素及作用机制可以结合能力—动机—机会(Ability-Motivation-Opportunity,AMO)框架加以理解。组织结构同质化、结构性晋升阻碍和职场性别劣势限制了女性中层管理者职业继续发展机会;社会性别分工认同、工作-家庭平衡成功观,以及低职场性别效能削弱了女性中层管理者职业继续发展的动机;由于工作压力和社会性别评价压力,以及职场任务导向认知、工具性内隐领导原型和性别特质的影响,许多女性中层管理者呈现出侧重任务导向,但任务导向执行低效的领导行为特点,降低了女性中层管理者的领导力,进而制约了女性中层管理者的职业继续发展能力。

大庆油田水驱开发技术及其发展方向

通过回顾大庆油田水驱开发技术发展历程,系统总结了近10年创新发展的水驱层系井网优化调整、近阻组合注水优化调整、区块及单井套损预警防控等油田主体开发技术。在客观分析大庆油田水驱主要矛盾问题的基础上,明确了水驱开发核心技术发展方向。在井网调整方面,攻关以“两驱协同、优选井型”为核心的井网优化调整技术,通过“二三结合”井网优化、分类储层加密调驱、井缝协同井网调整、多井型高效挖潜等井网调整新技术攻关,实现由水驱直井均匀加密向两驱协同、多井网多井型立体调整转变;在结构调整方面,攻关以“智能优化、水驱+”为核心的新一代综合调整技术,通过智能注采优化、低渗透储层功能性水驱、特低渗断块油藏压驱提产等技术攻关,实现由常规注采调整向智能调控、多方式补能转变;在套损防控方面,攻关以“层位预警、套损复产”为核心的套损精准防治技术,在深化地质力学机理研究基础上,发展套损层位精准预警技术、套损区复产挖潜技术,实现由区块、单井预警向大数据与地应力分析相结合的套损层位精准预警及防控转变。

中小企业“智改数转”动因、问题与实施路径研究

本文剖析了“智改数转”涵义、动因与现实意义;对中小企业实施“智改数转”的产业环境、政策环境进行了分析与研究,总结出中小企业实施“智改数转”面临的两大问题,即认识问题和基础薄弱。对于“智改数转”的思想认识、方案形成与具体实施,主张采取自下而上和自上而下两者相结合的形式,但其中自上而下的决策和实施过程需要占据主导地位。而对于企业“智改数转”基础,提出企业首先做好管理升级、实施两化融合、上ERP系统、进行大量的员工素质培训、技能培训、观念培训等。提出中小企业实施“智改数转”的参考路径为:诊断-全员实施-选择性实施-由内向外实施等。

跨介质集群轻小型巡飞弹关键技术与发展趋势

随着现代战争场景的不断复杂化,传统的、仅适用于单一工作环境的巡飞弹已无法满足实际作战需求。跨介质集群巡飞弹凭借其卓越的多情境作战能力,将为现代军事领域带来革命性的变革。文中从巡飞弹的基础设计、跨介质飞行器的独特性能以及集群技术的智能化管理三方面进行了全面分析,深入探究了跨介质集群巡飞弹的核心理论和技术。最后基于现代战争中装备、指挥及人员的新特点,对未来跨介质集群巡飞弹的发展趋势进行了展望。

Advancing immunosuppression in liver transplantation: A narrative review

Immunosuppression is essential to ensure recipient and graft survivals after liver transplantation(LT). However, our understanding and management of the immune system remain suboptimal. Current immunosuppressive therapy cannot selectively inhibit the graft-specific immune response and entails a significant risk of serious side effects, i.e., among others, de novo cancers, infections, cardiovascular events, renal failure, metabolic syndrome, and late graft fibrosis, with progressive loss of graft function. Pharmacological research, aimed to develop alternative immunosuppressive agents in LT, is behind other solidorgan transplantation subspecialties, and, therefore, the development of new compounds and strategies should get priority in LT. The research trajectories cover mechanisms to induce T-cell exhaustion, to inhibit co-stimulation, to mitigate non-antigen-specific inflammatory response, and, lastly, to minimize the development and action of donor-specific antibodies. Moreover, while cellular modulation techniques are complex, active research is underway to foster the action of T-regulatory cells, to induce tolerogenic dendritic cells, and to promote the function of B-regulatory cells. We herein discuss current lines of research in clinical immunosuppression, particularly focusing on possible applications in the LT setting.

公共风险与经济中长期发展——分析框架、影响机制及政策选择

当前,全球经济中长期发展面临的主要问题是公共风险的衍化:由经济增长速度减缓向预期转弱、社会供需形成负反馈机制衍化;由就业岗位不足向工资风险溢价上升衍化;由刺激政策力度不够向结构性改革防范化解风险效能不足衍化。中国也不例外。所有的公共风险最终会转化为个人、企业和政府的成本,影响企业资产负债表、现金流量表,尤其会导致风险折现率提高、要素成本上升、经济潜在增长率下降。因此,必须高度重视公共风险治理,避免公共风险水平上升可能引发的经济长期衰退。基于对公共风险持续扩散的内在根源的剖析,本文提出当前应妥善处理六大关系,即发展与安全,数字经济与实体经济,农民市民化与乡村振兴,多元目标与政策协同,经济调控与经济治理,地方政府能力与事权、财权、财力匹配,从而实现对公共风险的有效对冲。

不同培养基对小鼠卵母细胞体外成熟质量及发育潜能的影响

背景:近年,未成熟卵母细胞体外成熟技术的需求逐渐增加。卵母细胞成熟受多种因素影响,其中培养基的选择尤为重要,目前尚无统一方案。目的:用不同成熟培养基对生发泡期卵母细胞体外成熟,研究其对卵母细胞质量及发育潜能的影响。方法:用G-1^(TM)PLUS培养基、CZB培养基和M16培养基对生发泡期卵母细胞体外成熟,并以体内成熟卵母细胞为对照组,比较各组间的体外受精和早期胚胎发育能力。对于各组成熟后卵母细胞,采用免疫荧光方法评估线粒体功能,共聚焦显微镜实时成像系统检测钙震荡情况。结果与结论:①3组之间第一极体排出率无明显差异(P>0.05);②G-1^(TM)PLUS组体外受精率(52.86±11.24)%高于M16组(37.76±6.70)%和CZB组(30.62±5.51)%;CZB组的囊胚率(36.23±6.63)%低于对照组(78.16±4.17)%、G-1^(TM)PLUS组(55.75±7.63)%和M16组(53.36±6.33)%;③与对照组相比,仅CZB组的纺锤体长宽比增加;④CZB组线粒体功能差于对照组、G-1^(TM)PLUS组及M16组,并出现CZB组线粒体异常凝集现象;⑤受精后CZB组及M16组的钙震动频率显著高于G1组和对照组。综上所述,在小鼠卵母细胞体外成熟过程中,G-1^(TM)PLUS、CZB及M16培养基的体外成熟率无差异,但G-1^(TM)PLUS培养基有更高的受精率和囊胚形成率。

世界中低运量轨道交通制式发展及适用性分析

中低运量轨道交通作为超大或特大城市地铁网络的加密和补充、大城市乃至中等城市的骨干线路,在解决城市交通问题方面发挥着重要作用。在对65个国家496座城市的2 600余条中低运量轨道交通运营线路调研的基础上,构建世界中低运量轨道交通线路数据库。基于该数据库,得到世界范围内运营的齿轨、有轨电车、悬挂式单轨、自动旅客捷运系统(automated people mover system,APM)、跨座式单轨、直线电机系统、中低速磁浮、电子导向胶轮系统和导轨式胶轮系统9种中低运量轨道交通制式,线路里程共18 744.84 km;并统计中低运量轨道交通在各大洲、各国家的分布情况,结果显示其主要分布在欧洲的德国、俄罗斯等32个国家,线路里程达13 256.0 km,占比70.7%;统计各制式在不同国家/城市、不同城市特征、不同线路功能定位的分布情况,结果显示,中低运量轨道交通制式主要服务于人口小于300万的城市,76.25%的有轨电车线路、47.82%的跨座式单轨线路和42.11%的直线电机系统线路作为骨干线,84.62%的齿轨线路作为旅游线,70.73%的APM线路作为机场专线。同时,梳理总结各制式的起源与发展,并对技术特点和参数、适用性进行分析。研究成果以期为我国城市中低运量轨道交通制式的选择提供参考。

抗性湿地松体细胞胚的发育、成熟及萌发

为加快抗松针褐斑病湿地松体细胞胚胎发生技术的产业化应用进程,本文研究了肌醇浓度、脱落酸(ABA)及其添加方式、基本培养基、聚乙二醇(PEG-6000)浓度、琼脂糖种类及浓度、活性炭浓度、液体悬浮培养等因素对抗性湿地松体细胞胚的发育、成熟及萌发的影响。结果表明:添加8 g/L肌醇较适宜,过高浓度的肌醇则不利于湿地松体细胞胚发育;ABA可以采用高压灭菌;基本培养基、ABA、PEG-6000互作对湿地松体细胞胚的成熟影响很大,基本培养基以LP为最佳,ABA的最适浓度为10m g/L,PEG-6000以添加25、50 g/L为宜;在湿地松体细胞胚的成熟培养过程中,PEG-6000的浓度不能高于100 g/L;在湿地松体细胞胚的成熟培养基中,添加60 g/L蔗糖最合适;湿地松体细胞胚的成熟培养基中添加0.5 g/L或1 g/L的活性炭较适宜;培养基状态对体细胞胚的高频率诱导具有一定的影响,悬浮培养以100 mL三角瓶装培养液30 mL、摇床转速130 r/min为宜,液体转固体时吸取培养液1 mL为宜;未建立成熟的体细胞胚发生体系前,以采用固体培养为佳。最佳成熟培养基、激素及部分添加物组合为LP+10 mg/L ABA+50 g/L PEG-6000+60 g/L蔗糖+1.0 g/L活性炭。