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991.
Anne Marsh 《History of Photography》2013,37(2):114-117
Abstract In postmodern criticism the camera has often been seen as an apparatus of control, one of the surveillance mechanisms of the state, in the service of its institutions and immersed in its technologies of power. The metaphor of the camera as a weapon, as analysed by Susan Sontag in the early 1970s, describes an unbalanced and non-reciprocal relationship between photographer and subject.1 One is the hunter, the other the prey; one is the agent, the other the victim. This theoretical paradigm was consolidated in the 1980s when structuralist critics started to analyse nineteenth-century photographic archives held in libraries, institutions and museums.2 Much of this criticism followed the work of Michel Foucault who used Jeremy Bentham's model of the Panopticon to analyse the controlling mechanism of the gaze in modern institutions.3 I am aware that aligning Foucault with structuralism will appear problematic to some; however, the way in which some of his work has been adapted by postmodern critics of photography does underline the determinism of his theory. For a lucid analysis, see Joan Copjec, Read my Desire: Lacan against the Historicists, Cambridge, MA: MIT Press 1994, 1–10. For a different perspective, sympathetic to Foucault, see Geoffrey Batchen, Burning with Desire: The Conception of Photography, Cambridge, MA: MIT Press 1997. Although Foucault's concept of power is productive and he admits to sites of resistance, he is pessimistic about the possibilities of such resistance.4 Discipline and Punish, upon which many theories of photographic surveillance are predicated, constructs disciplinary power as ‘the nonreversible subordination of one group of people by another’.5 相似文献
992.
993.
Grillon Marie-Laure; Krebs Marie-Odile; Gourevitch Rapha?l; Giersch Anne; Huron Caroline 《Canadian Metallurgical Quarterly》2010,24(1):101
Investigations of memory impairment in schizophrenia have frequently revealed a strategic processing deficit at encoding. The authors studied an early encoding process, refreshing (in this case, thinking of a stimulus that has just-previously been presented), and its impact on recognition memory in schizophrenia. Following simultaneous presentation of three words or a single word in the top, middle, or bottom position of the screen, 25 patients with schizophrenia and 25 control participants saw and read a new word (read condition), or a word presented on the previous screen (repeat condition), or saw a dot indicating that they should think of and say the last word to have appeared in that position (refresh condition). Later, on a surprise test, participants were asked to recognize words seen previously and give a Remember, Know, or Guess response according to whether they recognized each on the basis of conscious recollection, familiarity, or guessing. The cognitive operation of refreshing was impaired in schizophrenia: patients were slower on 1-word trials and less accurate on 3-word trials to refresh a word, and their Remember responses did not benefit from refreshing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
994.
A comparative assessment of thin-film photovoltaic production processes using the ELECTRE III method 总被引:1,自引:0,他引:1
The use of renewable energy sources for the production of electric power brings huge benefits both in terms of environmental protection as well as savings in non-renewable resources. Photovoltaic stands out from other renewable energy sources for its simplicity and the modularity of its energy conversion system. To date, the most highly developed technology for the construction of solar cells is one based on mono and polycrystalline silicon. An alternative production line is currently under development to produce, thin-film modules. There are currently a variety of processes and materials available to make thin-film cells but their relative costs and performance differ. Therefore, it would be useful to make a comparative evaluation of the different processes using a multiple criteria method. 相似文献
995.
Juxta‐terminal Helix Unwinding as a Stabilizing Factor to Modulate the Dynamics of Transmembrane Helices 下载免费PDF全文
Armin Mortazavi Venkatesan Rajagopalan Kelsey A. Sparks Dr. Denise V. Greathouse Prof. Roger E. Koeppe II 《Chembiochem : a European journal of chemical biology》2016,17(6):462-465
Transmembrane helices of integral membrane proteins often are flanked by interfacial aromatic residues that can serve as anchors to aid the stabilization of a tilted transmembrane orientation. Yet, physical factors that govern the orientation or dynamic averaging of individual transmembrane helices are not well understood and have not been adequately explained. Using solid‐state 2H NMR spectroscopy to examine lipid bilayer‐incorporated model peptides of the GWALP23 (acetyl‐GGALW(LA)6LWLAGA‐amide) family, we observed substantial unwinding at the terminals of several tilted helices spanning the membranes of DLPC, DMPC, or DOPC lipid bilayers. The fraying of helix ends might be vital for defining the dynamics and orientations of transmembrane helices in lipid bilayer membranes. 相似文献
996.
997.
An interview study of 81 former political prisoners investigated whether posttraumatic stress disorder (PTSD) is related to the way individuals process the prison experience. In contrast to participants without PTSD, those with chronic or remitted PTSD were more likely to perceive mental defeat and an overall feeling of alienation from other people. Chronic PTSD was also related to perceived negative and permanent change in their personalities or life aspirations. The groups did not differ in their attempts to gain control during imprisonment. Evidence for a relationship between political commitment and PTSD was mixed. The results suggest that mental defeat, alienation, and permanent change are related to PTSD after interpersonal trauma and may need to be addressed in treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
A temporal multiscale modelling applied to fatigue damage evolution in cortical bone is presented. Microdamage accumulation
in cortical bone, ensued from daily activities, leads to impaired mechanical properties, in particular by reducing the bone
stiffness and inducing fatigue. However, bone damage is also known as a stimulus to bone remodelling, whose aim is to repair
and generate new bone, adapted to its environment. This biological process by removing fatigue damage seems essential to the
skeleton lifetime. As daily activities induce high frequency cycles (about 10,000 cycles a day), identifying two-time scale
is very fruitful: a fast one connected with the high frequency cyclic loading and a slow one related to a quasi-static loading.
A scaling parameter is defined between the intrinsic time (bone lifetime of several years) and the high frequency loading
(few seconds). An asymptotic approach allows to decouple the two scales and to take into account history effects (Guennouni
and Aubry in CR Acad Sci Paris Ser II 20:1765–1767, 1986). The method is here applied to a simple case of fatigue damage and
a real cortical bone microstructure. A significant reduction in the amount of computation time in addition to a small computational
error between time homogenized and non homogenized models are obtained. This method seems thus to give new perspectives to
assess fatigue damage and, with regard to bone, to give a better understanding of bone remodelling. 相似文献
999.
Difficult visual search is often attributed to time-limited serial attention operations, although neural computations in the early visual system are parallel. Using probabilistic search models (Dosher, Han, & Lu, 2004) and a full time-course analysis of the dynamics of covert visual search, we distinguish unlimited capacity parallel versus serial search mechanisms. Performance is measured for difficult and error-prone searches among heterogeneous background elements and for easy and accurate searches among homogeneous background elements. Contrary to the claims of time-limited serial attention, searches in heterogeneous backgrounds instead exhibited nearly identical search dynamics for display sizes up to 12 items. A review and new analyses indicate that most difficult as well as easy visual searches operate as an unlimited-capacity parallel analysis over the visual field within a single eye fixation, which suggests limitations in the availability of information, not temporal bottlenecks in analysis or comparison. Serial properties likely reflect overt attention expressed in eye movements. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Anne Hahn Timo Stöver Gerrit Paasche Marian Löbler Katrin Sternberg Henning Rohm Stephan Barcikowski 《Advanced Engineering Materials》2010,12(5):B156-B162
Polymeric nanomaterials are gaining increased interest in medical applications due to the sustained release of bioactive agents. Within this study nanomaterials are fabricated using laser ablation of silver and copper in polymer‐doped organic liquids thus allowing to produce customized drug release systems. A strategy is shown to determine the therapeutic window for cells relevant for cochlear implant electrodes, defined by the viability of L929 fibroblasts, PC12 neuronal cells, and spiral ganglion cells on different concentrations of silver and copper ions. The distribution of nanoparticles within the silicone polymer matrix is determined using transmission electron microscopy. Hexane doped with 1% silicone resin is found to be an appropriate liquid matrix to fabricate a nanocomposite with a constant ion release rate. Silver ions of 10 µmol L?1 or copper ions of 100 µmol L?1 cause a suppression of tissue growth without inhibiting neuronal cell growth. The copper nanoparticle content of 0.1 wt% of the silicone composite releases ion concentrations which fit the therapeutic window. 相似文献