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121.
Bermúdez (Philosophy of psychology: a contemporary introduction, Routledge, London, 2005) identifies the “Interface Problem” as the central problem in the philosophy of psychology: how commonsensical psychological explanations can be integrated with lower-level (cognitive, biological, etc.) explanations? In particular, since folk psychology is meant to provide causal explanations on a par with, say, neurobiological explanations, the question of how to understand the relation between the two layers arises naturally. Donald Davidson claimed that the interface problem is actually ill-posed and put forward his version of the “Autonomy Picture”, the view known as anomalous monism. This work reviews Davidson’s proposal in the light of digital universes: we model the key claims of the theory using cellular automata and show that Davidson’s original version of the Autonomy Picture (which differs, in some respects, from what is discussed by Bermúdez) is immune to two arguments against autonomy.  相似文献   
122.
The identification of the chemical nature of varnish is essential for art restorers in order to choose a suitable solvent during its removal. Until today, such identification has been performed using chemical analysis after sampling. An innovative technique is presented here, using ultraviolet (UV) fluorescence spectroscopy. The method is nondestructive, workable in situ, and leads to results in real time. It is based on the comparison between the emission spectrum of an unknown varnish with those of fresh, artificially aged, or old reference resins and varnishes, for different monochromatic excitation wavelengths. The resin and the nature of the varnish as spirit, oil, or mixed can thus be identified. Various examples are presented on home-made samples applied on fluorescent backgrounds and on real works of art.  相似文献   
123.
The auxiliary function method is an efficient technique for solving the radiative tranfer equation without adding any assumption and was applied until now only for theoretical stratified media. The first application (to our knowledge) of the method to a real case, the human skin, is presented. This makes it possible to validate the method by comparing model results with experimental reflectance spectra of real skin. An excellent agreement is obtained for a multilayer model of the skin made of 22 sublayers and taking into account the anisotropic phase function of the scatterers. Thus there is the opportunity to develop interest in such models by quantitatively evaluating the influence of the parameters commonly used in the literature that modify skin color, such as the concentration of the scatterers and the thickness of each sublayer.  相似文献   
124.
Emerging non-volatile memory technologies are promising due to their anticipated capacity benefits, non-volatility, and zero idle energy. One of the most promising candidates is resistive random access memory (RRAM) based on resistive switching (RS). This paper reviews the development of RS device technology including the fundamental physics, material engineering, three-dimension (3D) integration, and bottom-up fabrication. The device operation, physical mechanisms for resistive switching, reliability metrics, and memory cell selector candidates are summarized from the recent advancement in both industry and academia. Options for 3D memory array architectures are presented for the mass storage application. Finally, the potential application of bottom-up fabrication approaches for effective manufacturing is introduced.  相似文献   
125.
Nanofluids are colloidal dispersions of nanoparticles in homogenous base fluids. Previous studies have shown that nanofluids can increase pool boiling critical heat flux (CHF) by forming a porous deposition on the heated surface. However, questions remain whether nanoparticles can further enhance the CHF on a passively engineered heat transfer surface, such as a sandblasted metal plate. In this study, three water-based nanofluids (diamond, zinc oxide and alumina) were used to modify sandblasted stainless steel 316 plate heaters via boiling induced deposition. The pool boiling CHF of these pre-coated heaters increased by up to 35% with respect to that of the bare, sandblasted heaters. The enhancements are highest for alumina and zinc oxide nanofluids. Detailed surface characterization of these pre-coated heaters showed different surface morphology depending on the type of nanofluids used. Additionally, the deposited nanoparticles layers were found to alter the wettability of the heaters. Contact angle measurement provided quantitative data to determine possible CHF enhancement based on existing correlations.  相似文献   
126.
Bisphenol A (BPA) is largely used as a monomer in some types of plastics. It accumulates in tissues and fluids and is able to bypass the placental barrier, affecting various organs and systems. Due to huge developmental processes, children, foetuses, and neonates could be more sensitive to BPA-induced toxicity. To investigate the multi-systemic effects of chronic exposure to a low BPA dose (100 μg/L), pregnant Wistar rats were exposed to BPA in drinking water during gestation and lactation. At weaning, newborn rats received the same treatments as dams until sex maturation. Free and conjugated BPA levels were measured in plasma and adipose tissue; the size of cerebral ventricles was analysed in the brain; morpho-functional and molecular analyses were carried out in the liver with a focus on the expression of inflammatory cytokines and Sirtuin 1 (Sirt1). Higher BPA levels were found in plasma and adipose tissue from BPA treated pups (17 PND) but not in weaned animals. Lateral cerebral ventricles were significantly enlarged in lactating and weaned BPA-exposed animals. In addition, apart from microvesicular steatosis, liver morphology did not exhibit any statistically significant difference for morphological signs of inflammation, hypertrophy, or macrovesicular steatosis, but the expression of inflammatory cytokines, Sirt1, its natural antisense long non-coding RNA (Sirt1-AS LncRNA) and histone deacetylase 1 (Hdac1) were affected in exposed animals. In conclusion, chronic exposure to a low BPA dose could increase the risk for disease in adult life as a consequence of higher BPA circulating levels and accumulation in adipose tissue during the neonatal period.  相似文献   
127.
It is well known that water disinfection through chlorination causes the formation of a mixture of disinfection by-products (DBPs), many of which are genotoxic and carcinogenic. To demonstrate the formation of such compounds, a pilot water plant supplied with water from Lake Trasimeno was set up at the waterworks of Castiglione del Lago (PG, Italy). The disinfectants, continuously added to pre-filtered lake water flowing into three different basins, were sodium hypochlorite, chlorine dioxide and peracetic acid, an alternative disinfectant used until now for disinfecting waste waters, but not yet studied for a possible use in drinking water treatment. The aim of this study was to evaluate the formation during the disinfection processes of some toxic compounds that could explain the genotoxic effects of drinking waters. Differently treated waters were concentrated by solid-phase adsorption on silica C(18) columns and toxicity was assessed in a line of human hepatoma cells (HepG2), a metabolically competent cellular line very useful for human risk evaluation. The seasonal variability of the physical-chemical water characteristics (AOX, UV 254 nm, potential formation of THM, pH and temperature) made indispensable experimentation with water samples taken during the various seasons. Autumn waters cause greater toxicity compared to those of other seasons, in particular dilution of the concentrate at 0.5l equivalent of disinfected waters with chlorine dioxide and peracetic acid causes a 55% reduction in cellular vitality while the cellular vitality is over 80% with the all other water concentrates. Moreover it is very interesting underline that non-cytotoxic quantities of the autumnal water concentrates cause, after 2h treatment, a decrease in GSH and a statistically significant increase in oxygen radicals, while after prolonged treatment (24h) cause a GSH increase, without variations in the oxygen radical content. This phenomenon could be interpreted as the cellular adaptation response to an initial oxidative stress.  相似文献   
128.
Tip20p is an 80 kDa cytoplasmic protein bound to the cytoplasmic surface of the endoplasmic reticulum (ER) by interaction with the type II integral membrane protein Sec20p. Both proteins are required for vesicular transport between the ER and Golgi complex. Recently, sec20–1 was found to be defective in retrograde transport. A collection of temperature-sensitive tip20 mutants are shown to be lethal in combination with ufe1–1, a target SNARE of the ER and ret2–1, yeast δ-COP. A subset of tip20 mutants was found to be lethal in combination with sec20–1, sec21–1, sec22–3 and sec27–1. Since all pairwise combinations of a tip20 mutant, sec20–1, and ufe1–1 are lethal, Tip20p and Sec20p might be part of the docking complex for Golgi-derived retrograde transport vesicles. Since carboxy-terminal tip20 truncations are lethal in combination with mutants in three coatomer subunits, Tip20p might be involved in binding or uncoating of COPI coated retrograde transport vesicles. © 1998 John Wiley & Sons, Ltd.  相似文献   
129.
Infrared thermometry was used to obtain first-of-a-kind, time- and space-resolved data for pool boiling phenomena in water-based nanofluids with diamond and silica nanoparticles at low concentration (<0.1 vol.%). In addition to macroscopic parameters like the average heat transfer coefficient and critical heat flux [CHF] value, more fundamental parameters such as the bubble departure diameter and frequency, growth and wait times, and nucleation site density [NSD] were directly measured for a thin, resistively heated, indium-tin-oxide surface deposited onto a sapphire substrate. Consistent with other nanofluid studies, the nanoparticles caused deterioration in the nucleate boiling heat transfer (by as much as 50%) and an increase in the CHF (by as much as 100%). The bubble departure frequency and NSD were found to be lower in nanofluids compared with water for the same wall superheat. Furthermore, it was found that a porous layer of nanoparticles built up on the heater surface during nucleate boiling, which improved surface wettability compared with the water-boiled surfaces. Using the prevalent nucleate boiling models, it was possible to correlate this improved surface wettability to the experimentally observed reductions in the bubble departure frequency, NSD, and ultimately to the deterioration in the nucleate boiling heat transfer and the CHF enhancement.  相似文献   
130.
The polyphenolic composition, antioxidant properties and multielement profile of selected red wines from Morocco were evaluated. The polyphenolic contents resulted higher than those reported elsewhere for the same variety of wines; the highest quantity was found in Cabernet Sauvignon, followed by Merlot, and last by Syrah wine. All of the wines tested showed very similar anthocyanin and flavonol patterns: individual compound contents resulted generally higher in comparison to conventional wines. The content of trans-resveratrol was significantly higher than that of cis-resveratrol in all of the wine samples. Particularly, Merlot showed the highest concentration of trans-resveratrol while Syrah exhibited the highest levels of cis-resveratrol. Reducing capacity resulted higher than antiradical property for all of the wines. The metal concentrations were below the official limits. The elemental pattern of wines were very similar, excepted V, Mn, Fe, Cu, As and Mo, for which Syrah markedly differed from the other wine samples.  相似文献   
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