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81.
The 5-HTTLPR is an insertion/deletion polymorphism in the promoter region of the serotonin transporter gene. Prior research has revealed associations between the short-allele variant of this polymorphism, enhanced self-reported negative emotionality, and hypersensitivity of fear relevant neural circuits. In a sample of 50 healthy women we examined the role of 5-HTTLPR for cognitive-affective processing of phylogenetical fear-relevant stimuli (spiders) in a dot probe task. In contrast to homozygote long-allele carriers (ll), participants carrying at least 1 short allele (ss and sl) selectively shifted attention toward pictures of spiders, when these were presented for a duration of 2,000 ms. These results argue for an involvement of 5-HTTLPR in cognitive processing of threatening stimuli and thus, underpin its general role for individual differences in negative affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
The optical properties of 3D metacrystals made of gold nanoparticles in protein nanocages are studied. These metacrystals have sizes of tens of micrometers and are of high structural and optical quality. Through microspectroscopy measurements and model calculations it is demonstrated that the metacrystals show plasmonic absorption in the green wavelength range and are largely transparent in the red and infrared ranges. By using empty nanocages as placeholders in the metacrystal lattice, it is possible to control how strongly the metamaterial absorbs. Measurements on a pyramidal metacrystal show that it deflects visible light. The deflection shows evidence for anomalous refraction at short wavelengths and normal refraction at long wavelengths. The refractive dispersion is ascribed to the optical dispersion relation of the plasmonic metamaterial.  相似文献   
83.
The Adaptive Solar Facade (ASF) is a modular, highly integrated dynamic building facade.The energetic behavior as well as the architectural expression of the facade can be controlled with high spatio-temporal resolution through individually addressable modules. We present the general design process, the current mechanical design, and simulation results on photovoltaic power production and building energy consumption. We introduce the controller concept and show results on solar tracking as well as user interaction. Lastly, we present our current and planned prototypes.  相似文献   
84.
We present a new epoxy-based negative-tone dry film photoresist (DFR) for fabricating multilayer microfluidic devices using a lamination process combined with a standard photolithography technology. As proof-of-concept, a complex 3D-hydrodynamic focusing device was produced via a six-layer lamination process of 33 µm-thick DFR layers. The bonding strength of the new DFR was tested on silicon, glass, and titanium substrates, respectively. A maximum bonding strength of 37 MPa was obtained for the dry film photoresist laminated on glass. No leakage was found, and burst tests proved excellent robustness and sealing reliability of the microchannels.  相似文献   
85.
Organic semiconductors are the centerpiece of several vibrant research fields from single‐molecule to organic electronics, and they are finding increasing use in bioelectronics and even classical polymer technology. The versatile chemistry and broad range of electronic functionalities of conjugated materials enable the bridging of length scales 15 orders of magnitude apart, ranging from a single nanometer (10?9 m) to the size of continents (106 m). This work provides a taste of the diverse applications that can be realized with organic semiconductors. The reader will embark on a journey from single molecular junctions to thin film organic electronics, supramolecular assemblies, biomaterials such as amyloid fibrils and nanofibrillated cellulose, conducting fibers and yarns for e‐textiles, and finally to power cables that shuffle power across thousands of kilometers.  相似文献   
86.
87.
Microwave dielectric measurements of dry and wet snow were made at nine frequencies betweeo 3 and 18 GHz, and at 37 GHz, using two free-space transmission systems. The measurements were conducted during the winters of 1982 and 1983. The following parametric ranges were covered: 1) liquid water content, 0 to 12.3 percent by volume; 2) snow density, 0.09 to 0.42 g cm-3; 3) temperature, 0 to-5 degC and-15degC (scattering-loss measurements); and 4) crystal size, 0.5 to 1.5 mm. The experimental data indicate that the dielectric behavior of wet snow closely follows the dispersion behavior of water. For dry snow, volume scattering is the dominant loss mechanism at 37 GHz. The applicability of several empirical and theoretical mixing models was evaluated using the experimental data. Both the Debye-like semi-empirical model and the theoretical Polder-Van Santen mixing model were found to describe adequately the dielectric behavior of wet snow. However, the Polder-Van Santen model provided a good fit to the measured values of the real and imaginary parts of wet snow only when the shapes of the water inclusions in snow were assumed to be both nonsymmetrical and dependent upon snow water content. The shape variation predicted by the model is consistent with the variation suggested by the physical mechanisms governing the distribution of liquid water in wet snow.  相似文献   
88.
This paper reports the design of a tailor made polymeric membrane by using poly(ethylene oxide)–poly(butylene terephthalate) (PEO‐PBT) multi‐block copolymers. Their properties are controlled by the fraction of the PEO phase and its molecular weight. To explain the effect of structural changes in copolymer membranes, transport properties of four gases (CO2, H2, N2, and CH4) are discussed. After characterization, the two best copolymers are selected in order to prepare tailor made blends by adding poly(ethylene glycol) (PEG). The best selected copolymer that contained 55 wt. % of 4000 g mol−1 PEO produced a blend with high CO2 permeability (∼190 barrer), which is twice the permeability of the pure copolymer. At the same time, an enhancement of CO2/H2 selectivity is observed (∼13). These results suggest that the morphology of PEO‐PBT can be well controlled by the addition of low‐molecular‐weight PEG, and consequently the gas transport properties can be tuned.  相似文献   
89.
In this article, the authors report 2 experiments that investigated the sources of information used in transfer and nontransfer tasks in artificial grammar learning. Multiple regression analyses indicated that 2 types of information about repeating elements were crucial for performance in both tasks: information about the repetition of adjacent elements and information about repetition of elements in the whole item. Similarity of test items to specific training items and chunk information influenced participants' judgments only in nontransfer tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
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