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1.
Obesity is a globally increasing health problem, entailing diverse comorbidities such as infectious diseases. An obese weight status has marked effects on lung function that can be attributed to mechanical dysfunctions. Moreover, the alterations of adipocyte-derived signal mediators strongly influence the regulation of inflammation, resulting in chronic low-grade inflammation. Our review summarizes the known effects regarding pulmonary bacterial and viral infections. For this, we discuss model systems that allow mechanistic investigation of the interplay between obesity and lung infections. Overall, obesity gives rise to a higher susceptibility to infectious pathogens, but the pathogenetic process is not clearly defined. Whereas, viral infections often show a more severe course in obese patients, the same patients seem to have a survival benefit during bacterial infections. In particular, we summarize the main mechanical impairments in the pulmonary tract caused by obesity. Moreover, we outline the main secretory changes within the expanded adipose tissue mass, resulting in chronic low-grade inflammation. Finally, we connect these altered host factors to the influence of obesity on the development of lung infection by summarizing observations from clinical and experimental data.  相似文献   
2.
鲁迅思想的矛盾性集中体现在他的《野草》中。这种矛盾并非简单的二元对立,而是充满着结构张力的逻辑两难,它们相互依存相互冲突,纷繁复杂的呈现在文本中,使得《野草》表现出多义特征。  相似文献   
3.
D-S证据理论是一种重要的决策级信息融合方法,但传统的Dempster证据合成规则会导致一些与直觉相悖的结果.针对该问题,在经典的Shafer折扣方法基础上,提出了一种综合可靠性和重要性因素的复合折扣因子计算方法.该方法首先借助证据包含度合理地定义了证据可靠性度量;然后综合证据清晰度、证据一致性和证据积累程度等因素,建立了证据重要性模型;最后两者通过乘法算子共同构成复合折扣因子.实验结果表明,文章方法的证据处理过程与生物学研究中人的信息积累过程一致,能够解决证据合成中的悖论问题,合成证据可靠有效.  相似文献   
4.
在哲学发展的过程中可以看到对逻辑悖论的特殊关注.探讨逻辑悖论的文化向度,体现了当代哲学发展对逻辑悖论关注的特殊所在.从思想内容、科学方法和人文精神阐释逻辑悖论的文化根据、文化力量和文化意义,明示从语用学维度研究逻辑悖论的重要性,能使人们深刻地认识和把握客观世界.在这一过程中,逻辑悖论为人们确立了新的思维方式,把人们带入了更加广阔的精神世界,从而不断赋予人的世界以新的意义.  相似文献   
5.
A true e-business enabled firm needs the support from a well-tuned enterprise resource planning (ERP) system for providing real time data. However, many companies complain that after their huge investments in ERP systems, they found the ERP systems do not bring them new orders, new profits, or competitive advantage as ERP vendors claim. Academic studies also found mixed results regarding ERP’s payoff. In line with resource based view (RBV), the study proposes an integrated model to shed light on the ERP value paradox. We try to answer “With what organizational resources and by building what firm specific capabilities, the investment in ERP systems may bring firms competitive advantage”. Using a sample of 150 ERP and e-business adopters in the US, we found that (1) organizational resources such as managerial skills and organizational change management play a more important role than IT resources (ERP, e-Business technologies) in generating business integration capability. (2) However, neither IT resources nor organizational resources directly provide firms with competitive advantage. Instead, business integration capability built from the two resources plays a mediating role through which business achieves competitive advantage.  相似文献   
6.
Despite the potential benefits of virtual teams, current literature suggests that virtual teamwork is rife with complex challenges. We frame some of these challenges as paradoxes inherent in the concept of virtual teamwork. Based on interviews with 42 leaders and members of virtual teams, we identify five paradoxes: (1) virtual teams require physical presence; (2) flexibility of virtual teamwork is aided by structure; (3) interdependent work in virtual teams is accomplished by members' independent contributions; (4) task-oriented virtual teamwork succeeds through social interactions; and (5) mistrust is instrumental to establishing trust among virtual team members. In addition, we identify strategies that respondents used to cope with, or 'survive' the paradoxes of virtual teamwork.  相似文献   
7.
设计的悖论     
当代设计出现不可避免的悖论,一方面,好的设计需要更多的推广和使用,另一方面,在当前情况下产品使用越多,对于环境的破坏和资源的浪费就越严重。设计师应该在新的时代对当前地球的状况有所承担。通过自己的设计来改变目前多数产品的能耗方式以及对环境的破坏,同时在潜移默化中来引导消费者进行更为合理的生活方式,使得人与自然更加和谐地相处。  相似文献   
8.
The value of information technology (IT) in a business production process has long been a debatable issue. Explanation of the so-called “productivity paradox” has been one of the central topics in this arena. Much work has focused on firm-level analyses. This paper investigates IT contribution at a country level, using production theory in microeconomics. It negates the relationship between IT value and productivity based on grouping of countries, when the individual analytical method is applied and technical efficiency is used as the performance criterion. Findings obtained by applying stochastic production frontiers to a comprehensive country-level panel data set suggest that the IT contributions, as determined by the increase or decrease in the technical efficiency, to individual countries differ in magnitude from a production frontier to another, but are robust. It also shows that IT spending does not necessarily improve technical efficiencies of individual countries, regardless of whether they are developed or developing countries, and that given technological changes, the so-called productivity paradox may exist in a country, no matter whether it is a developed or developing nation. Finally, the significant implications of the findings are presented.  相似文献   
9.
This paper aims at investigating the dynamical behaviors of a 3D rod moving on a rough surface with so-called Painlevé paradox. The condition for the occurrence of the Painlevé paradox in the rod is studied according to the theoretical results obtained from LCP’s method for spatial multibody systems. Numerical results obtained by inserting a compliant contact model into the rigid body model present a support for the assumption that a tangential impact is related to the spatial paradoxical situations. Furthermore, the tangential impact is analyzed by using the Darboux–Keller’s shock dynamics and are found with the same properties as the one in the planar rod: A tangential stick appears at the contact point during the impulsive process. With the help of the Stronge’s coefficient, an impact rule is developed to describe the dynamical behaviors of the 3D rod with paradoxical situations. Comparisons between numerical results obtained from Darboux’s model and the ones obtained from the compliant contact model are carried out and show well agreements.  相似文献   
10.
逻辑的批判     
逻辑批判就是考察思想内在的一致性、推理的必然性和论证的充分性,逻辑的要求是全部理性要求的底线,逻辑批判是一切理性批判的基础和前提,逻辑批判具有重要的理论意义和实践意义。  相似文献   
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