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181.
Past researches showed that empathy for pain not only triggers a resonance mechanism between other and self, but also is modulated by contextual factors. Using functional magnetic resonance imaging, the present study demonstrated that short-term media violence exposure reduced both pain ratings and also the activation of anterior insula and anterior mid-cingulate cortex to other’s pain. Thus, violence exposure modulated empathic responses to other’s pain based on a physiological desensitization.  相似文献   
182.
Abstract

Global warming – reality or fantasy? Certainly, global warming is a dystopia linked to other catastrophes in human history, such as the Flood and Noah's Ark. Noah's belief in God saved his life and the life of his family. In our time, we need to sustain our belief in the human capacity to cooperate and survive. This is a necessary background when thinking of the future and analysing the border between fantasy and reality, between fear and paranoia, and in the process in which a new worldview takes form.  相似文献   
183.
Parent–adolescent conflict has been demonstrated to relate to treatment adherence and glycemic control in adolescents with Type 1 diabetes. The present longitudinal study investigated how these variables were interrelated over time, and examined whether externalising and internalising symptoms function as mediating variables. A total of 109 adolescents with diabetes participated at four annual time points and completed measures on conflict with parents, internalising and externalising symptoms. Information on treatment non-adherence and glycemic control was obtained from treating physicians. Cross-lagged analyses from a structural equation modelling approach indicated that father–adolescent but not mother–adolescent conflict positively influenced treatment non-adherence over time, which, in turn, was associated with higher glycosylated haemoglobin-values. Further, externalising but not internalising symptoms were found to mediate the pathway from father–adolescent conflict to treatment adherence over time. Finally, mother–adolescent conflict was found to relate indirectly to treatment non-adherence through its relationship with externalising symptoms. Hence, the present longitudinal study provides evidence that externalising symptoms represent an important mechanism through which earlier experiences of parent–adolescent conflict may influence later treatment non-adherence and poorer glycemic control. Implications and suggestions for future research are outlined.  相似文献   
184.
185.
Posttraumatic stress disorder (PTSD) has been associated with deficits in the areas of verbal memory and learning, executive functioning, working memory, and attention in adults. Findings have been less consistent in the few studies examining neuropsychological functioning in childhood PTSD, which are often limited by comparing children with PTSD to children without trauma histories, making it unclear whether observed neuropsychological deficits are related to trauma exposure or to PTSD symptomatology. In an ethnically diverse sample of 62 children who witnessed intimate partner violence (n = 27 PTSD+ and 35 PTSD?), children with PTSD exhibited slower and less effective learning, heightened sensitivity to interference, and impaired effect of rehearsal on memory acquisition on the California Verbal Learning Test – Children's Version, a word list learning task. Both groups performed in the below average range on measures of executive functioning, attention, and intellectual ability.  相似文献   
186.
ABSTRACT

We report the formation of an icosahedral quasicrystal and its approximant in the Ga–Pd–Sc alloy. The primitive-type quasicrystal with a six-dimensional lattice constant of 0.713?nm formed in the melt-quenched Ga53Pd30Sc17 alloy, with a similar composition to that of the Ga55Pd30Sc15 1/1 approximant. The atomic-scale observation and chemical analysis of the 1/1 approximant by scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy showed that the approximant consisted of Tsai-type clusters with a characteristic chemical ordering. Furthermore, a series of approximants were observed in the Ga55Pd30RE15 alloys by replacing Sc with other rare-earth elements (REs) (RE?= Y, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu). These approximants, which have relatively small lattice constants and consequently smaller RE–RE distances compared with those for other RE-containing Tsai-type approximants, may be candidates for materials with novel electronic and magnetic properties similar to those observed in Au-based quasicrystals and approximants.  相似文献   
187.
Antiplane shear cracks in a harmonic square lattice have been studied in a molecular dynamics simulation. They can reach velocities larger than the shear wave velocity.  相似文献   
188.
Recently, low-frequency internal friction measurements on a series of Fe–Cr alloys by Konstantinovi? and Terentyev [M.J. Konstantinovi? and D. Terentyev, Mater. Sci. Eng. A 521–522 (2009) p.106] have demonstrated that increasing Cr concentrations lead to an increase in the strength of the β-relaxation at the cost of the γ-relaxation (Chambers’ notation). In the same concentration and temperature regime, the alloys show alloy softening. It is argued that both phenomena are due to the same process, namely the influence of foreign atoms on the transformation of the cores of a 0?1 1 1?/2 screw dislocations from their low-temperature configuration, capable of forming kink pairs on {1 1 0} planes, to their high-temperature configuration with kink-pair generation on {2 1 1} planes.  相似文献   
189.
Neodymium-doped silica nanocomposites were prepared from an acid-catalysed sol–gel solution followed by heat treatment. The structural and microstructural properties of the prepared samples as a function of sintering temperature and Nd concentration are reported. Fourier transform infrared spectra show that phase separation occurs during heat treatment. The presence of Nd2O3 and α-Nd2Si2O7 phases in the samples was established by X-ray diffraction (XRD), and transmission electron microscopy (TEM) micrographs revealed the microstructure of the nanocomposites. From XRD patterns, the crystallite size was determined using the Debye–Scherrer formula, while the particle size was estimated from TEM micrographs. The results suggest that sintering at high temperature enhances the crystallinity and density of Nd2O3–SiO2 nanocomposites, while the high concentration of neodymium prevents the crystallization of SiO2.  相似文献   
190.
Zn1???xCoxO (ZC) [x?=?0, 1, 3, 5, 7 and 9?mol%] thin films were prepared by sol–gel combined metallo-organic decomposition method. The films were deposited on the Si substrate with spin-coating technique and annealed at 600?°C for 3?h. X-ray diffraction pattern shows the formation hexagonal wurtzite phase and distortion (c/a) decreases with increasing Co concentration in ZnO. The average grain size is measured using Scherer relation. Atomic force microscopy is used to confirm the formation of nanograins resulted by the use of polyethylene glycol as surfactant. The photoluminescence was recorded by using He-Cd laser of excitation wavelength 325?nm in wavelength region of 350–650?nm which exhibits some influence of Co doping on the multiplication of defects such as O vacancies, Zn interstitials and grain boundary defects. All thin films show room temperature ferromagnetism except pure ZnO which is diamagnetic and 9?mol% of Co shows paramagnetism. This behaviour is interpreted as due to fluctuations in the magnetic ordering, depending on grain size and site location in grain boundaries or oxygen vacancies.  相似文献   
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