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81.
Roger J. Ingham Yuedong Wang Janis C. Ingham Anne K. Bothe Scott T. Grafton 《Brain and language》2013
Developmental stuttering is known to be associated with aberrant brain activity, but there is no evidence that this knowledge has benefited stuttering treatment. This study investigated whether brain activity could predict progress during stuttering treatment for 21 dextral adults who stutter (AWS). They received one of two treatment programs that included periodic H215O PET scanning (during oral reading, monologue, and eyes-closed rest conditions). All participants successfully completed an initial treatment phase and then entered a phase designed to transfer treatment gains; 9/21 failed to complete this latter phase. The 12 pass and 9 fail participants were similar on speech and neural system variables before treatment, and similar in speech performance after the initial phase of their treatment. At the end of the initial treatment phase, however, decreased activation within a single region, L. putamen, in all 3 scanning conditions was highly predictive of successful treatment progress. 相似文献
82.
Gert-Jan De Bruijn Stef P. J. Kremers EmEly De Vet Jascha De Nooijer Willem Van Mechelen Johannes Brug 《Psychology & health》2013,28(8):899-916
The present study examined if habit strength moderated the influence of intention on fruit consumption in a Dutch adult sample (N?=?521, 46.3% males, mean age?=?34.50, SD?=?10.87), using the theoretical relations of the Theory of Planned Behaviour (TPB). TPB variables and habit strength were assessed at baseline. Fruit consumption was assessed with a validated questionnaire five weeks later. Three groups were created: low habit strength (n?=?180), medium habit strength (n?=?185) and high habit strength (n?=?156). Confirmatory factor analyses and multi-group path analyses were performed using AMOS 4.0. A good fit was obtained for the overall measurement model and the structural models. Multi-group path analyses showed that intention was a significant predictor of fruit consumption in the low habit (β?=?0.36, p?<?0.001) and medium habit group (β?=?0.30, p?<?0.001), but a non-significant predictor in the high habit group (β?=?0.05, p?=?0.596). Implications for information-based and motivation-based interventions are discussed. 相似文献
83.
Both positive and negative changes are commonly reported by cancer survivors, and both may impact quality of life. Yet few studies have directly compared the associations of positive and negative changes across multiple life domains with multiple aspects of well-being. This study examined positive and negative changes and their conjoint relation to a range of well-being indices. We used correlational and regression analyses of data from 237 young to middle aged (X?=?45.3?years) cancer survivors, several years after treatment. Measures included demographic and medical variables, medical post-cancer positive and negative changes on multiple life domains, and a range of positive and negative adjustment indices. Demographic factors, especially income, related to both positive and negative outcomes. On average, participants reported no change on most life domains, although modest amounts of both positive and negative changes were reported. Negative change, rather than positive change, was closely associated with cancer survivors’ adjustment. Detailed measurement of both positive and negative changes – as well as lack of change – is important to advance understanding of cancer's impact on survivors. 相似文献
84.
Jackie L. Micklewright Tricia Z. King Robin D. Morris Mary K. Morris 《Child neuropsychology》2013,19(6):522-527
The Rey Auditory Verbal Learning Test was utilized to examine attention, learning, and memory abilities in 42 children with cerebellar (N?=?18) and third ventricle tumors (N?=?24). Children with cerebellar tumors exhibited significant auditory attentional impairments and displayed adequate encoding and retrieval across subsequent learning and memory trials. In contrast, children with third ventricle tumors exhibited average auditory attentional abilities, but they displayed mild encoding deficits across trials 2–5. Furthermore, the third ventricle group's compromised performance on the delayed recall trial and average performance on the delayed recognition trial is suggestive of underlying retrieval deficits. 相似文献
85.
Luigi Cannavacciuolo 《Philosophical Magazine Letters》2013,93(12):527-535
ABSTRACTThe fundamental origin of the reversal transition during crystal growth has been investigated by Monte Carlo simulations. Evidence is provided supporting the geometrical nature of the transition, arising from the broken translational invariance at the growth front and the interactions of multipoles of opposed parity. The range of interactions, the details of the force field and model are irrelevant to the occurrence and only determine the functional behaviour of the relevant physical quantities like the localisation of the critical point and the morphology of the phase diagram. 相似文献
86.
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
87.
Rozaliya Barabash Yanfei Gao Yinan Sun Soo Yeol Lee Hahn Choo Peter K. Liaw 《Philosophical Magazine Letters》2013,93(8):553-565
The crack-tip deformation behavior during a single overload, fatigue test of ferritic stainless steel, and Ni-based HAYNES 230 superalloy is studied at different structural levels using (1) neutron-diffraction, from which both the elastic-lattice strain and volume-averaged total dislocation densities are obtained, (2) polychromatic X-ray microdiffraction to probe the geometrically necessary dislocations and boundaries distribution, and (3) an irreversible and hysteretic cohesive interface model which has been implemented into a finite element framework to simulate the stress/strain evolution near the fatigue crack tip. Neutron strain measurements and finite element simulations are in qualitative agreement on the macroscopic length scale. Large plastic deformation induced by the overload and the resulting compressive residual strains are observed in front of the crack tip after the overload, and are the principal reason for the fatigue-crack-growth retardation. Strong strain gradients surrounding the crack propagation result in the formation of a high density of geometrically necessary dislocations near the fractured surface and cause local lattice rotations on the submicron level. 相似文献
88.
Grain-boundary migration is demonstrated to proceed by lateral propagation of a small step in a (113), [110] symmetric Al tilt grain-boundary. In-situ high-resolution (transmission) electron microscopy (HREM) at 523K allowed the study of atomic-scale detail at video rates during the migration process. The grain-boundary translational states on both sides of the step are identical, which leads to a step dislocation. This defect can move laterally by a combination of climb and glide. Dynamic HREM images indicate considerable atomic agitation within the dislocation core. A detailed temporal analysis of the step movements shows small random displacements of the dislocation core. 相似文献
89.
The formation of an ω-Al7Cu2Fe phase during laser cladding of quasicrystal-forming Al65Cu23.3Fe11.7 alloy on a pure aluminium substrate is reported. This phase is found to nucleate at the periphery of primary icosahedral-phase particles. A large number of ω-phase particles form an envelope around the icosahedral phase. On the outer side, they form an interface with an α-Al solid solution. Detailed transmission electron microscopic observations show that the ω phase exhibits an orientation relationship with the icosahedral phase. Analysis of experimental results suggests that the ω phase forms by precipitation on an icosahedral phase by heterogeneous nucleation and grows into the aluminium-rich melt until supersaturation is exhausted. The microstructural observations are explained in terms of available models of phase transformations. 相似文献
90.
A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti–B–N films with various B contents. The results show that the mean grain size decreases with increase of B content and the grain-size distribution conforms to a log-normal function when the hardness approaches a maximum value. The transition from normal to log-normal distributions can be determined by analysis in terms of a minimum information criterion. The origin of a log-normal size distribution probably results from heterogeneity arising from a diffusion-drift process. 相似文献