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1.
这本专著总结了作者多年来最重要的研究成果。研究表明,人的大脑皮层具有获得驱动力的独特能力.正是这种能力创造了人类社会,并促使人类社会不断进化。作者认为,人类社会目前还处于反复实验的发展阶段,但其最终必将由现在的不可知状态逐渐过渡到理性指导的平衡状态。通过对获得性驱动力的特殊分析及以前曾认为不可知的脑机理的发现,作者对社会生活的发展及艺术、科学的起源给出了合理的生理学解释。本书的目的是要论证即使在脑及其自我的关系中,自然规律仍然是简单的,而不是不可知的。 相似文献
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Ankeny and Leonelli (2016) propose “repertoires” as a new way to understand the stability of certain research programs as well as scientific change in general. By bringing a more complete range of social, material, and epistemic elements into one framework, they position their work as a correction to the Kuhnian impulse in philosophy of science and other areas of science studies. I argue that this “post-Kuhnian” move is not complete, and that repertoires maintain an internalist perspective. Comparison with an alternative framework, the “sociotechnical imaginaries” of Jasanoff and Kim (2015), illustrates precisely which elements of practice are externalized by Ankeny and Leonelli. Specifically, repertoires discount the role of audience, without whom the repertoires of science are unintelligible, and lack an explicit place for ethical and political imagination, which provide meaning for otherwise mechanical promotion of particular research programs. This comparison reveals, I suggest, two distinct modes of scholarship, one internalist and the other critical. While repertoires can be modified to meet the needs of critical STS scholars and to completely reject Kuhn's internalism, whether or not we do so depends on what we want our scholarship to achieve. 相似文献
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Matthew D. Hitchings Philip Townsend Ehmke Pohl Paul D. Facey D. Hugh Jones Paul J. Dyson Ricardo Del Sol 《Cellular and molecular life sciences : CMLS》2014,71(24):4911-4926
Dps proteins are members of an extensive family of proteins that oxidise and deposit iron in the form of ferric oxide, and are also able to bind DNA. Ferroxidation centres are formed at the interface of anti-parallel dimers, which further assemble into dodecameric nanocages with a hollow core where ferric oxide is deposited. Streptomyces coelicolor encodes three Dps-like proteins (DpsA, B and C). Despite sharing the conserved four-helix bundle organisation observed in members of the Dps family, they display significant differences in the length of terminal extensions, or tails. DpsA possess both N- and C-terminal tails of different lengths, and their removal affects quaternary structure assembly to varying degrees. DpsC quaternary structure, on the other hand, is heavily dependent on its N-terminal tail as its removal abolishes correct protein folding. Analysis of the crystal structure of dodecamers from both proteins revealed remarkable differences in the position of tails and interface surface area; and provides insight to explain the differences in biochemical behaviour observed while comparing DpsA and DpsC. 相似文献
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Molla R. Islam Yongfeng Gao Xue Li Qiang Matthew Zhang Menglian Wei Michael J. Serpe 《科学通报(英文版)》2014,59(32):4237-4255
Stimuli-responsive polymers have the extraor- dinary ability to change their physical and/or chemical state after they "detect" a change in their environment; their response depends dramatically on their chemical compo- sition. This property has been used for a plethora of applications; this review highlights their utility for human health. Specifically, this review will highlight efforts in the areas of sensing and biosensing, antimicrobial/antifouling coatings, tissue engineering and regenerative medicine, and drug delivery. Specific examples are given in each of these areas, with some focus on our work engineering poly(N- isopropylacrylamide)-based microgels and other respon- sive systems. 相似文献
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Luiz A. Rocha Joseph D. DiBattista Tane H. Sinclair-Taylor Michael L. Berumen 《Journal of Natural History》2020,54(15-16):1019-1023
ABSTRACT Here we document three cases of mimicry in coral reef fishes not previously reported in the literature involving two groupers (Epinephelus leucogrammicus and Plectropomus marisrubri) and a soapfish (Diploprion drachi) as mimics, and two wrasses (Larabicus quadrilineatus and Cheilinus quinquecinctus) and a blenny (Meiacanthus nigrolineatus) as models. All three cases are of aggressive mimicry, with a predatory species mimicking a harmless one, and in one of the cases, the mimicry is also Müllerian, where both the predator and harmless species are unpalatable. 相似文献
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Milne JC Lambert PD Schenk S Carney DP Smith JJ Gagne DJ Jin L Boss O Perni RB Vu CB Bemis JE Xie R Disch JS Ng PY Nunes JJ Lynch AV Yang H Galonek H Israelian K Choy W Iffland A Lavu S Medvedik O Sinclair DA Olefsky JM Jirousek MR Elliott PJ Westphal CH 《Nature》2007,450(7170):712-716
Calorie restriction extends lifespan and produces a metabolic profile desirable for treating diseases of ageing such as type 2 diabetes. SIRT1, an NAD+-dependent deacetylase, is a principal modulator of pathways downstream of calorie restriction that produce beneficial effects on glucose homeostasis and insulin sensitivity. Resveratrol, a polyphenolic SIRT1 activator, mimics the anti-ageing effects of calorie restriction in lower organisms and in mice fed a high-fat diet ameliorates insulin resistance, increases mitochondrial content, and prolongs survival. Here we describe the identification and characterization of small molecule activators of SIRT1 that are structurally unrelated to, and 1,000-fold more potent than, resveratrol. These compounds bind to the SIRT1 enzyme-peptide substrate complex at an allosteric site amino-terminal to the catalytic domain and lower the Michaelis constant for acetylated substrates. In diet-induced obese and genetically obese mice, these compounds improve insulin sensitivity, lower plasma glucose, and increase mitochondrial capacity. In Zucker fa/fa rats, hyperinsulinaemic-euglycaemic clamp studies demonstrate that SIRT1 activators improve whole-body glucose homeostasis and insulin sensitivity in adipose tissue, skeletal muscle and liver. Thus, SIRT1 activation is a promising new therapeutic approach for treating diseases of ageing such as type 2 diabetes. 相似文献