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131.
Increasingly serious environmental problems have generated a large number of small and medium-sized green innovative enterprises. Against the background of rapid technological changes and increasingly fierce market competition, survival is the main problem faced by these enterprises. Exploring the mechanisms and core elements that determine the survival of green innovation enterprises is of great practical significance for improving the survival probability of green innovation enterprises and achieving environmental improvement through green innovation.In this paper, twenty-nine enterprises that have won the title of “Top 10 Green Innovative Enterprises” in China are considered the research objects, and the fuzzy set qualitative comparative analysis (fsQCA) method is used to examine the path combinations that affect the survival of enterprises from the perspectives of resource-based and dynamic capabilities. The findings are as follows. First, government support is key to the survival of green innovative enterprises; second, China's green innovative enterprises have a research and development dilemma, and only matching high R&D capacity with product competitiveness can enhance their survival capabilities; and third, the lack of resource base capacity is the key factor affecting the failure of green enterprises, and dynamic capacity is the key factor for the survival of green innovative enterprises. The main contribution of this paper to the field of management is that enterprises must always pay attention to the coordinated development of internal resource-based capability and external dynamic capability. Conversely, the Chinese government should provide high R&D support to enterprises with competitive products so that these enterprises can rapidly grow into leading enterprises through continuous innovation and drive the sustained and rapid development of China's green innovation industry. 相似文献
132.
行会生存对提高游戏用户的活跃度和留存率有着积极的作用。目前行会生存分析方法是使用分类法,即把行会是否生存看作一个二分类问题来处理,其未能充分利用行会纵向数据,不能及时反映行会的状态变化和生存趋势。采用纵向-生存联合模型,充分利用游戏行会纵向的状态变化特征和成员行为特征,预测行会的生存状态。实验表明,纵向-生存联合模型相比传统的Cox比例风险模型,综合性能提高了56.6%,相比分类算法提高了预测性能,如逻辑回归提高了11.9%。实验中发现:成员权利等级标准差对行会生存呈现了正向的影响,说明了行会内成员权利等级有着良好的分布对行会的生存有着重要作用;成员私聊次数标准差和成员PK次数标准差对行会生存有着积极的影响,说明行会成员行为差异性的重要性;生存时间对行会有着负向的影响,即行业已生存时间越长,越不利于行会的生存。 相似文献
133.
俞泽鹏 《佳木斯工学院学报》2011,(5):763-765
研究条件copula的相关性质,给出生存条件copula的概念研究了它的性质及和条件copula的联系,并研究了几种条件copula之间的关系,为利用条件copula描述条件随机变量的相关性并研究其相关性质提供了方便,最后提出可以进一步讨论的几个问题. 相似文献
134.
Moossavi S Tuttle AB Vachharajani TJ Plonk G Bettmann MA Majekodunmi O Russell GB Regan JD Freedman BI 《Hemodialysis international. International Symposium on Home Hemodialysis》2008,12(1):80-84
The need for reliable, long-term hemodialysis vascular access remains critical. To determine the long-term outcomes of transposed basilic vein arteriovenous fistulae (BVT) and their comparability with other vascular accesses, we determined retrospectively the primary and secondary patency rates in 58 BVT and in a total of 58 arteriovenous fistulae (AVF) and arteriovenous grafts (AVG) at a single center. Fifty-eight BVT were placed in 57 individuals, 69% after prior vascular access failure. Ten BVT failed before initial use and 2 patients expired with functioning accesses before dialysis initiation. In all 58 BVT, 46.8+/-10.8% functioned at 3 years, with median survival 30.8 months. Limiting analyses to the 46 BVT that were ultimately accessed, 3-year primary and secondary patency rates were 38.3+/-7.7% and 56.5+/-12.6%, respectively. Lower ejection fraction (p=0.054) and greater numbers of prior permanent dialysis catheters (p=0.005) were present in those with failed BVT. Compared with AVF, BVT had similar 3-year primary and secondary patency rates. The secondary patency rate was significantly better for BVT vs. AVG over the observation period; at 3 years, the rates were 56.5+/-12.6% vs. 9.1+/-6.0% (p=0.002), respectively. Basilic vein arteriovenous fistulae are valuable hemodialysis accesses. Although nearly 20% of newly placed BVT will not function before first use, those that are functional have median survivals exceeding 6 years, and 38% will not require intervention within 3 years of initial use. 相似文献
135.
Pai-Chi Teng Shu-Pin Huang Chia-Hsin Liu Ting-Yi Lin Yi-Chun Cho Yo-Liang Lai Shu-Chi Wang Hsin-Chih Yeh Chih-Pin Chuu Deng-Neng Chen Wei-Chung Cheng Chia-Yang Li 《International journal of molecular sciences》2021,22(21)
In the recent decade, the importance of DNA damage repair (DDR) and its clinical application have been firmly recognized in prostate cancer (PC). For example, olaparib was just approved in May 2020 to treat metastatic castration-resistant PC with homologous recombination repair-mutated genes; however, not all patients can benefit from olaparib, and the treatment response depends on patient-specific mutations. This highlights the need to understand the detailed DDR biology further and develop DDR-based biomarkers. In this study, we establish a four-gene panel of which the expression is significantly associated with overall survival (OS) and progression-free survival (PFS) in PC patients from the TCGA-PRAD database. This panel includes DNTT, EXO1, NEIL3, and EME2 genes. Patients with higher expression of the four identified genes have significantly worse OS and PFS. This significance also exists in a multivariate Cox regression model adjusting for age, PSA, TNM stages, and Gleason scores. Moreover, the expression of the four-gene panel is highly correlated with aggressiveness based on well-known PAM50 and PCS subtyping classifiers. Using publicly available databases, we successfully validate the four-gene panel as having the potential to serve as a prognostic and predictive biomarker for PC specifically based on DDR biology. 相似文献
136.
Over the past decades, a large amount of data has been accumulated in various subfields of glycobiology. However, much clinically relevant data and many tools are still not widely used in medicine. Synthetic glycoconjugates with the known structure of glycans are an accurate tool for the study of glycan-binding proteins. We used polyacrylamide glycoconjugates (PGs) including PGs with tumour-associated glycans (TAGs) in immunoassays to assess the prognostic potential of the serum level of anti-glycan antibodies (AG Abs) in gastrointestinal cancer patients and found an association of AG Abs with survival. The specificity of affinity-isolated AG Abs was investigated using synthetic and natural glycoconjugates. AG Abs showed mainly a low specificity to tumour-associated and tumour-derived mucins; therefore, the protective role of the examined circulating AG Abs against cancer remains a challenge. In this review, our findings are analysed and discussed in the context of the contribution of bacteria to the AG Abs stimulus and cancer progression. Examples of the influence of pathogenic bacteria colonising tumours on cancer progression and patient survival through mechanisms of interaction with tumours and dysregulated immune response are considered. The possibilities and problems of the integrative study of AG Abs and the microbiome using high-performance technologies are discussed. 相似文献
137.
Freshwater mussels are often relocated from existing beds for both conservation and management reasons. In this study, we empirically tested whether the habitat type at the destination site was important in predicting the success of mussel relocation. In 1993, four species of freshwater mussels were relocated in the Apalachicola River in Florida, into three distinct habitat types: stable sand, limestone/sand and cobble. The conditional probability of survival of relocated mussels varied by species and habitat. Two species were considered habitat specialists, one species was considered a habitat generalist and recovery rates for the fourth species were too low to assess habitat preferences. We show empirically that microhabitat is important in the survival of relocated mussels and that the habitat-specific criteria for relocation is species specific. These results suggest that survival of relocated mussels can be enhanced if species-specific site selection criteria are developed using quantitative information. © 1997 John Wiley & Sons, Ltd. 相似文献
138.
This study evaluates the effect of death as a competing event to the development of dementia in a longitudinal study of the cognitive status of elderly subjects. A multi-state Markov model with three transient states: intact cognition, mild cognitive impairment (M.C.I.) and global impairment (G.I.) and one absorbing state: dementia is used to model the cognitive panel data; transitions among states depend on four covariates age, education, prior state (intact cognition, or M.C.I., or G.I.) and the presence/absence of an apolipoprotein E-4 allele (APOE4). A Weibull model and a Cox proportional hazards (Cox PH) model are used to fit the survival from death based on age at entry and the APOE4 status. A shared random effect correlates this survival time with the transition model. Simulation studies determine the sensitivity of the maximum likelihood estimates to the violations of the Weibull and Cox PH model assumptions. Results are illustrated with an application to the Nun Study, a longitudinal cohort of 672 participants 75+ years of age at baseline and followed longitudinally with up to ten cognitive assessments per nun. 相似文献
139.
Chih‐Hui Lai PhD 《Journal of Computer-Mediated Communication》2014,19(4):839-854
Applying an ecological and evolutionary perspective, this study examines the evolution and the sustainability of “mixed‐mode groups,” a type of voluntary association created and organized online to interact physically in geographically defined ways. Meetup.com is a website that facilitates the creation and coordination of mixed‐mode groups. Analysis of interviews with 34 Meetup group organizers and a longitudinal analysis of 100 randomly selected Meetup groups revealed the evolutionary processes at the group and population level, respectively. Specifically, the ecological factor of population density, the demographic factor of group age, the group's profit orientation, experience of leadership change and shared leadership, and external ties played decisive roles in predicting group survival. Implications of the findings for theoretical and practical contributions are discussed. 相似文献
140.