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951.
Although an increasing number of children are born with prenatal methadone or buprenorphine exposure, little is still known about the potential long-term effects of these opioids. The aim of this study was to investigate executive function (EF) in children of women in opioid maintenance therapy (OMT). A total of 66 children (aged 48–57 months) participated in the study, 35 of which had histories of prenatal methadone or buprenorphine exposure. EF was measured using a battery of neuropsychological tests and the Behavior Rating Inventory of Executive Function—Preschool Version (BRIEF-P). Results showed that children of women in OMT perform lower on tasks of short-term memory and inhibition compared to nonexposed children, which was mainly associated with lower maternal education and employment rate. The OMT group scored significantly lower on all EF tasks compared to the nonexposed group, although scores fell within the average range on all measures. The development of these children should be monitored to assess for the possible problem behaviors and to promote optimal outcomes.  相似文献   
952.
Experimental tests of strain-gradient plasticity theory rely on studies of the size effect (smaller is stronger) in micromechanical testing. The plastic strain gradient is varied by varying the size of the specimen. This confounds the direct effects of the size and the effects of the strain gradient. We propose experiments on foil sandwich structures in which these parameters are separated. Preliminary results suggest that it is the foil thickness that determines the strength, not the strain gradient.  相似文献   
953.
A novel, instrumented microindentation technique was successfully used to measure the temperature associated with the martensitic transformation leading to the recovery of plastic strain in a Nickel–Titanium (NiTi) shape memory alloy. Following a standard indentation cycle, the indenter was partially unloaded such that a good contact was maintained between indenter and specimen surface. The onset and finish temperature of the martensitic transformation, the associated volume contraction, and the amount of the recovered plastic deformation were determined by quantifying the indenter displacement as a function of temperature. These experiments were compared to conventional measurements of the transformation temperature by differential scanning calorimetry and compression testing.  相似文献   
954.
Dense single-wall-carbon-nanotube-(SWCNT)-reinforced alumina nanocomposites have been fabricated by a novel spark-plasma-sintering technique. Anisotropic thermal properties have been found in carbon nanotube composites. The introduction of ropes of SWCNTs gives rise to a decrease in the transverse thermal diffusivity with increasing carbon nanotube content while it does not change the in-plane thermal diffusivity. This is scientifically interesting and technologically important for the development of materials for novel thermal barrier coatings.  相似文献   
955.

A model of the structure of two-dimensional foam (cells separated by circular arcs (films) meeting at threefold vertices) is considered. Films that are so curved as to be nearly semicircular arcs are problematic for conventional foam structure computations, which aim to identify the pressures needed to achieve specified bubble areas. When the films have near semicircularity, tiny variations in pressure can lead to large changes in the computed bubble area, and hence a failure to meet the specified targets. A new algorithm for determining foam structure is presented. It is based on 'freezing' most of the system, except the nearly semicircular arcs, and then finding the particular bubble pressures associated with the latter via an analytic approximation. This procedure is shown to work well for structure relaxation in a small bubble cluster. Large relaxed bubble clusters are considered briefly at the end of the paper.  相似文献   
956.

{111} stacking faults and nanotwins in epitaxial BaTiO3 thin films on MgO substrates have been investigated by high-resolution transmission electron microscopy. In many cases, the stacking faults and nanotwins were found to be accompanied by partial dislocations. These partial dislocations can be classified as two different types, analogous to the situation in the fcc structure. One is of the Shockley type with the Burgers vector (a/3)<112>. The other is of the Frank type with the Burgers vector (a/3)<111>. The movements of both types of partial can lead to the {111} stacking faults and the {111} twins observed in these films.  相似文献   
957.
The nucleation of voids at the initial stage of hollow nanoshell formation is described in terms of the thermodynamics of nucleation in systems of finite size (or small systems) pumped with vacancies by interdiffusion-driven vacancy influx. Crossovers from suppressed nucleation to metastable nucleus formation and then to stable nucleus formation are analysed, describing, in particular, the possibility of significant supersaturations with vacancies of the metallic core. It is shown that at higher temperatures it becomes more favourable to nucleate at once a large single void instead of multiple tiny voids.  相似文献   
958.
An inverse “smaller is stronger” trend is predicted on the basis of molecular dynamics simulations of α-titanium (Ti) single-crystal nanopillars orientated for double prismatic slips when the nanopillars are less than 7?nm wide. This trend is attributed to a significant increase in the surface energy due to the nucleation and propagation of edge dislocations on the surface of the pillars.  相似文献   
959.
Abstract

Regenerative medicine (RM) in Japan lays strong emphasis on a specific trajectory of its development, which deploys human induced pluripotent stem (iPS) cells as the primary sources for the technology. The technique to create these stem cells was developed in 2006 by a Japanese stem cell scientist, Shinya Yamanaka, and since its applicability to human cells was established about a year later, this new type of cells has become to be considered as a potential substitute for human embryonic stem cells. While the clinical value of these cells are yet to be confirmed, the Japanese Ministry of Education, Culture, Sports, Science and Technology decided to concentrate its support on iPS cells research and turned it into a national project. This decision reflected the state's vision of initiating the transition to a knowledge-based society, which was adopted in the 1990s to tackle the prolonged deflation in the country. As the research became intertwined with this policy vision, however, the Ministry came to see bringing its success as more important than ever, while other trajectories of RM were left underrated and largely unsupported. Industrial actors counteracted this situation and developed an initiative to recognize existing technical capability in the country, but its impact has been so far negligible. This indicates that the nation is locked in the particular trajectory of RM. Hence, this Japanese RM research enterprise presents an interesting case to understand how states' commitment may not only shape the course of scientific research but also reduce flexibility in technological development.  相似文献   
960.
While prolonged exposure is considered one of the “gold standard” and recommended treatments for post traumatic stress disorder (PTSD), it has been poorly utilised in clinical practice. Individuals with PTSD often find it too distressing to confront memories, and therapists may be uncomfortable using the therapy. A new Emotional Processing Therapy is described in which an emotional approach to prolonged exposure provides individuals with a new insight into how trauma is processed. A conceptual analysis of exposure suggests that it is exposure to distressing emotional experiences which is a key element. Viewing it as an emotion-based therapy, allows the creative addition of new emotional elements. Through exploring the individual’s emotional processing style, previously learned and unhelpful patterns can be addressed, and the addition of an “emotional preparation” phase helps them understand why it is important to face emotionally distressing memories before exposure sessions begin. Emotional Processing Therapy is intuitive and makes sense to those affected by PTSD. It is framed in an emotional context and is presented as part of a lifestyle change that may reduce the likelihood of psychological problems developing in the future.  相似文献   
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