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921.
Using an analogy in science and everyday life is a double-edged sword because they are accompanied by alternative ideas, in addition to scientific concepts. Schools and public education explain global warming by making a common analogy between this phenomenon and greenhouse effects (Chen in Philos Cogn Sci 105–114, 2012). Unfortunately, this analogy sometimes produces various incorrect explanatory mental models. To construct a correct understanding of global warming, it is necessary: first, to investigate the attributes of analogical reasoning; second, to understand these features by restructuring the greenhouse analogy; and third, to explore the problems and benefits of the greenhouse analogy. The characteristics of relations, rather than objects, must be mapped according to the principle of systematicity, but the public tends to preserve the attributes of the base domain, which is mapped relatively easily. In conclusion, certain facets of the prevailing greenhouse analogy cause a distorted public view of climate change. We must use the greenhouse analogy and yet simultaneously emphasize the relations and attributes highlighted and hidden in the analogy during evaluation.  相似文献   
922.
Love and Realism     
In this reply I try to show that, contrary to Milberry’s apparent assertion, the general intellect of the multitude does not have the explanatory robustness she accredits to it (following both Virno and the Hardt and Negri of the Empire trilogy). Digital network technologies are currently overwhelmingly effective in proletarianizing and disempowering the cognitariat and only an active technopolitics of deproletarianization could reverse this hegemonic situation. In my response to Verbeek, I attempt to correct his misinterpretation (shared by Milberry) of the Stieglerian approach as being dialectical in nature and show that, far from reinstating the humanist dichotomy between human beings and technologies, my analysis assumes their original, albeit fundamentally ambiguous and even ‘uncanny’ [unheimlich] interconnection. I conclude with pointing out some implications of this view for a ‘really realistic’ political theory of technology.  相似文献   
923.
Pieter Lemmens’ neo-Marxist approach to technology urges us to rethink how to do political philosophy of technology. First, Lemmens’ high level of abstraction raises the question of how empirically informed a political theory of technology needs to be. Second, his dialectical focus on a “struggle” between humans and technologies reveals the limits of neo-Marxism. Political philosophy of technology needs to return “to the things themselves”. The political significance of technologies cannot be reduced to its origins in systems of production or social organization, but requires study at the micro-level, where technologies help to shape engagement, interaction, power, and social awareness.  相似文献   
924.
To study the effect of cooperative advertising on the supply chain of deteriorating items, this paper establishes a Stackelberg game model for a two-echelon deteriorating items supply chain composed of one manufacturer and one retailer under a given support program with an exogenous participation rate. The manufacturer as the leader determines the wholesale price and production rate, and the retailer as the follower determines the retail price and advertising strategies. The strategies of the players under the decentralized scenario and the centralized scenario are respectively characterized. Numerical simulations and sensitivity analysis are conducted to gain some managerial insights. It is shown that the pricing, advertising and production strategies are negatively correlated to deteriorating coefficient, and both the profit and the channel efficiency decrease with deteriorating coefficient; The interaction between price, advertising investment and production rate results in a higher retail price of the centralized channel compared to that of the decentralized channel; Implementing the cooperative advertising program does improve the performance of the supply chain in some cases and the participation rate roughly at 0.5 is most preferable, but it is also possible to distort incentive and damage the channel performance when the participation rate reaches a relatively high level.  相似文献   
925.
Dual hesitant fuzzy set (DHFS) is a new generalization of fuzzy set (FS) consisting of two parts (i.e., the membership hesitancy function and the non-membership hesitancy function), which confronts several different possible values indicating the epistemic degrees whether certainty or uncertainty. It encompasses fuzzy set (FS), intuitionistic fuzzy set (IFS), and hesitant fuzzy set (HFS) so that it can handle uncertain information more flexibly in the process of decision making. In this paper, we propose some new operations on dual hesitant fuzzy sets based on Einstein t-conorm and t-norm, study their properties and relationships and then give some dual hesitant fuzzy aggregation operators, which can be considered as the generalizations of some existing ones under fuzzy, intuitionistic fuzzy and hesitant fuzzy environments. Finally, a decision making algorithm under dual hesitant fuzzy environment is given based on the proposed aggregation operators and a numerical example is used to demonstrate the effectiveness of the method.  相似文献   
926.
With the rapid growth of e-commerce, customers increasingly write online reviews of the product they purchase. These customer reviews are one of the most valuable sources of information affecting selection of products or services. Summarizing these customer reviews is becoming an interesting area of research, inspiring researchers to develop a more condensed, concise summarization for users. However, most of the current efforts at summarization are based on general product features without feature’s relationship. As a result, these summaries either ignore feedback from customers or do a poor job of reflecting the opinions expressed in customer reviews. To remedy this summarization shortcoming, we propose a feature network-driven quadrant mapping that captures and incorporates opinions from customer reviews. Our focus is on construction of a feature network, which is based on co-occurrence and sematic similarities, and a quadrant display showing the opinions polarity of feature groups. Moreover, the proposed approach involves clustering similar product features, and thus, it is different from standard text summarization based on abstraction and extraction. The summarized results can help customers better understand the overall opinions about a product.  相似文献   
927.
为研究有阻尼多跨连续梁在横向激励下的位移响应,采用整体分析的方法,在BernoulliEuler梁理论的基础上建立求解连续梁的横向振动方程,求得了有阻尼多跨连续梁的位移响应函数,同时求得了有阻尼条件下的固有频率方程和振型函数。  相似文献   
928.
Intercellular communications play a vital role during tissue patterning, tissue repair, and immune reactions, in homeostasis as well as in disease. Exosomes are cell-derived secreted vesicles, extensively studied for their role in intercellular communication. Exosomes have the intrinsic ability to package multiple classes of proteins and nucleic acids within their lumens and on their membranes. Here, we explore the hypothesis that exosomal targeting may represent a cellular strategy that has evolved to deliver specific combinations of signals to specific target cells and influence normal or pathological processes. This review aims to evaluate the available evidence for this hypothesis and to identify open questions whose answers will illuminate our understanding and applications of exosome biology.  相似文献   
929.
To sustain the bio-energetic demands of growth, proliferation, and effector functions, the metabolism of immune cells changes dramatically in response to immunologic stimuli. In this review, I focus on B cell metabolism, especially regarding the production of intestinal IgA antibody. Accumulating evidence has implicated not only host-derived factors (e.g., cytokines) but also gut environmental factors, including the possible involvement of commensal bacteria and diet, in the control of B cell metabolism during intestinal IgA antibody production. These findings yield new insights into the regulation of immunosurveillance and homeostasis in the gut.  相似文献   
930.
The efficiency of drug research and development has paradoxically declined over the last decades despite major scientific and technological advances, promoting new cost-effective strategies such as drug repositioning by systematic screening for new actions of known drugs. Here, we performed a screening for positive allosteric modulators (PAMs) at melanocortin (MC) receptors. The non-steroidal anti-inflammatory drug fenoprofen, but not the similar compound ibuprofen, presented PAM activity at MC3, MC4, and MC5 receptors. In a model of inflammatory arthritis, fenoprofen afforded potent inhibition while ibuprofen was nearly inactive. Fenoprofen presented anti-arthritic actions on cartilage integrity and synovitis, effects markedly attenuated in Mc3r?/? mice. Fenoprofen displayed pro-resolving properties promoting macrophage phagocytosis and efferocytosis, independently of cyclooxygenase inhibition. In conclusion, combining repositioning with advances in G-protein coupled receptor biology (allosterism) may lead to potential new therapeutics. In addition, MC3 PAMs emerged as a viable approach to the development of innovative therapeutics for joint diseases.  相似文献   
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