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991.
Using the colorant proteic complex labell with Tc-99 m. we visualize--by the first time--the carotideal glomus in the human in 6 volunteers and one patient with tumor. The results are very encorageous: the method was simple and safe (one single dose endovenously) and hardless (no radiotoxicity presents in 3 months of clinical and laboratory controls) and there is a good visualization by scan of carotideal bodies "in vivo", in human being. We think this new method and labell compound could be useful in research and medical diagnoses. 相似文献
992.
J. M. Chappé J. Gavoille N. Martin J. Lintymer J. Takadoum 《Journal of Materials Science》2006,41(17):5639-5645
Dc reactive sputtering was successfully implemented to deposit titanium oxynitride thin films using a titanium metallic target, argon, nitrogen and water vapour as reactive gases. The nitrogen partial pressure was kept constant during every deposition whereas that of the water vapour was systematically changed from 0 to 0.1 Pa. The study aims at comparing the structural and mechanical properties of the coatings deposited at room temperature (293 K) and at 673 K. Surface morphology of the film was examined by atomic force microscopy and showed different aspects according to the growth temperature. Topography mainly depends on the amount of water vapour introduced during the deposition process. Some significant changes of the crystallographic structure, due to the high substrate temperature were correlated with the evolution of the surface aspect and roughness parameters. Determination of the phase occurrence by X-ray diffraction was also carried out and appeared to be a significant parameter in understanding the evolution of mechanical properties like nanohardness (H
n) and Young’s modulus (E). H
n and E values obtained by nanoindentation ranged from 16.5 to 7 GPa and from 240 to 100 GPa, respectively. For both temperatures, mechanical properties of titanium oxynitride thin films were notably reduced as a function of the water vapour supply, especially for partial pressures higher than 4 × 10−2 Pa. These mechanical behaviours were correlated and discussed with the phase occurrence and the amorphous structure of titanium oxynitride thin films. 相似文献
993.
O. Bretcanu S. Spriano C. Brovarone Vitale E. Verné 《Journal of Materials Science》2006,41(4):1029-1037
Ferrimagnetic glass-ceramics could be used for magnetic induction hyperthermia. This technique is utilised for the destruction
of solid neoplastic diseases by application of an alternating magnetic field. Biocompatible ferrimagnetic materials could
be easily incorporated into a tumour and could generate heat mainly by hysteresis loss.
A ferrimagnetic glass-ceramic in the system SiO2–Na2O–CaO–P2O5–FeO–Fe2O3 has been prepared by melting of the coprecipitation-derived raw materials. This glass-ceramic contains a unique crystalline
phase, magnetite, embedded in an amorphous matrix. Magnetite crystals precipitate during cooling from melting temperature.
This glass-ceramic would no longer require any nucleation and growth thermal treatment, since the maximal quantity of magnetite
crystals was produced during cooling. The average unit-cell parameter, crystallite size of magnetite, and the quantitative
ratio of the crystallographic phases in the glass-ceramic samples were evaluated using two different methods. Similar results
were obtained with both methods. The magnetite crystals are about 50 nm in dimensions. The samples contain 45 wt% of magnetite,
homogeneously distributed in the amorphous residual matrix.
The as prepared glass-ceramic has a saturation magnetisation of 34 A·m2/kg and a coercive force of 6.7 kA/m. The estimated magnetic loss/cycle under the magnetic field up to 796 kA/m is around
1.45 mJ/g. The specific power loss of this glass-ceramic under a magnetic field of 40 kA/m and a frequency of 440 kHz is 25 W/g.
This material showed a bioactive behaviour, as after 2 weeks of soaking in a simulated body fluid the formation of a hydroxylapatite
layer on their surface was observed. This feature makes it also suitable for bone cancer. 相似文献
994.
Besides space laboratories for in-orbit experimentation, Earth based facilities for laboratory experimentation are of paramount importance for the enhancement on liquid bridge knowledge. In spite of the constraints imposed by simulated microgravity (which force to work either with very small size liquid bridges or by using the Plateau tank technique, amongst other techniques), the availability and accessibility of Earth facilities can circumvent in many cases the drawbacks associated with simulated microgravity conditions. To support theoretical and in orbit experimental studies on liquid bridges under reduced gravity conditions, several ground facilities were developed at IDR. In the following these ground facilities are briefly described, and main results obtained by using them are cited. 相似文献
995.
We investigate a quantum-correction method for Monte Carlo device simulation. The method consists of reproducing quantum mechanical
density-gradient simulation by classical drift-diffusion simulation with modified effective oxide thickness and work function
and using these modifications subsequently in Monte Carlo simulation. This approach is found to be highly accurate and can
be used fully automatically in a technology computer-aided design (TCAD) workbench project. As an example, the methodology
is applied to the Monte Carlo simulation of the on-current scaling in p- and n-type MOSFETs corresponding to a 65 nm node technology. In particular, it turns out that considering only the total threshold
voltage shift still involves a significant difference to a Monte Carlo simulation based on the combined correction of oxide
thickness and work function. Ultimately, this quantum correction permits to consider surface scattering as a combination of
specular and diffusive scattering where the conservation of energy and parallel wave vector in the specular part takes stress-induced
band structure modifications and hence the corresponding surface mobility changes on a physical basis into account. 相似文献
996.
Oxidation state of titanium was determined in CaO‐SiO2‐TiOx slags in the composition range 25‐53 percent CaO, 27‐46 percent SiO2, 10‐55 percent TiOx at 1873K using gas equilibration method. In the experiments, slags with different titanium oxide contents were equilibrated with a known carbon monoxide and carbon dioxide ratio. The results were used to determine the Ti3+ and Ti4+ contents as well as the activity coefficient ratio of corresponding oxides in the slag. The dependence of the activity coefficient ratio as a function of oxygen partial pressure was determined. 相似文献
997.
Reviews the book Protecting children from domestic violence: Strategies for community intervention, edited by Peter J. Jaffe, Linda L. Baker, and Alison J. Cunningham (see record 2005-04430-000). The book emerged from the International Conference on Children Exposed to Domestic Violence that was held in London, Ontario in 2001. It begins with an excellent chapter by Jeffrey Edleson synthesizing the literature on the impact of exposure to domestic violence on children. Edleson's chapter is followed by two papers examining emerging assessments and treatment programs. The second section of the book addresses current thinking about individual and group intervention approaches. The third section of the book examines broader system level responses, including public awareness and school-based campaigns, as well as responses by the courts and police. This is a well-organized collection of papers that provides a good overview of the state of knowledge and innovative practice in an emerging field of practice. Protecting Children from Domestic Violence provides practitioners, policy makers, and researchers with an excellent overview of current knowledge and practices in working with children exposed to domestic violence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
999.
This article discusses a model for teaching psychotherapy theory through an integrative structure from the start of graduate students' training. This model articulates an ordering structure for the reputed 400+ so-called "theories" of psychotherapy. The rationale for such a structure highlights one dimension among several--that is, the recognition that a vast majority of mental health practitioners describe their orientation as eclectic or integrative. Professionals in training are encouraged to use this structure as an organizing principle to create the underpinnings for future professional development. The structure informs all aspects of a graduate-level course, including its syllabus, the textbooks selected, the reader, learning objectives, and tools for learning outcome assessment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Stern Emily R.; Horvitz Jon C.; C?té Lucien J.; Mangels Jennifer A. 《Canadian Metallurgical Quarterly》2005,19(1):54
The authors explored the effect of Parkinson's disease (PD) on the generation and maintenance of response readiness in a simple reaction time task. They compared performance of idiopathic PD patients without dementia, age-matched controls, and younger controls over short (1-, 3-, and 6-s) and long (12- and 18-s) foreperiod intervals. After each trial, the authors probed memory for visual information that also had to be maintained during the trial interval. Patients and controls did not differ overall in their ability to maintain readiness over long delays. However, within the PD group only, errors in maintaining visual information were correlated with difficulty in maintaining readiness, suggesting that systems impaired in PD may facilitate the maintenance of processing in both motor and cognitive domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献