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81.
We report a patient with a parkinsonian syndrome induced by sertraline (Zoloft), an SSRI antidepressant, whose symptoms resolved after the drug was discontinued. This case prompted us to investigate the effect of sertraline on dopamine metabolism in animals. Sertraline (30 mg/kg, i.p.) or placebo (vehicle) was administered to two groups of six normal, anesthetized rats and using cerebral microdyalisis extracellular striatal levels of dopamine, the dopamine metabolites (HVA and DOPAC), as well as the serotonin metabolite 5-HIIA were monitored. In animals pre-treated with sertraline, DOPAC, HVA, and 5-HIAA levels were significantly decreased compared to control animals (p < 0.01). These data indicate that sertraline has an effect on dopamine metabolism, which may alter function in the striatum and induce a parkinsonian syndrome.  相似文献   
82.
Metopic synostosis is a relatively simple form of craniosynostosis, resulting from premature fusion of the metopic suture. In this pathology different degrees of dysmorphia of the anterior cranial fossa and the presence of associated anomalies of the skull might enable specific subgroups to be identified. Since most functional and cosmetic anomalies benefit from early surgical treatment, over the last few years neurosurgeons have been forced to elaborate less drastic, but nonetheless effective, surgical techniques. In the present report we analyze the surgical results obtained in a series of 62 infants with trigonocephaly operated on within their 1st year of life. Patients were subdivided into two groups (group I: 8 patients; group II: 54 patients) according to the specific dysmorphic characteristics of the frontal bone and anterior cranial fossa, and the presence of compensatory deformities affecting the anterior cranial base and temporo-parietal region. All the patients were treated using one of two relatively simple surgical techniques (procedure A: inversion of two hemifrontal bone flaps--48 cases; procedure B: the "shell" operation--14 cases). Both surgical procedures appeared to be effective, allowing adequate functional and cosmetic correction of the cranial deformity. In patients operated on following procedure B surgical time and blood loss were dramatically reduced. Long-term outcomes were satisfactory in all cases, irrespective of the surgical technique used. In the group II patients, however, progressive normalization of the interorbital distance was constantly observed, suggesting a different degree of stenotic involvement at the level of the anterior cranial base in these patients.  相似文献   
83.
Solid-state additive manufacturing and repairing by cold spraying: A review   总被引:1,自引:0,他引:1  
High-performance metal additive manufacturing (AM) has been extensively investigated in recent years because of its unique advantages over traditional manufacturing processes. AM has been applied to form complex components of Ti, Fe or Ni alloys. However, for other nonferrous alloys such as Al alloys, Mg alloys and Cu alloys, AM may not be appropriate because of its melting nature during processing by laser, electron beam, and/or arc. Cold spraying (CS) has been widely accepted as a promising solid-state coating technique in last decade for its mass production of high-quality metals and alloys, and/or metal matrix composites coatings. It is now recognized as a useful and powerful tool for AM, but the related research work has just started. This review summarized the literature on the state-of-the-art and problems for CS as an AM and repairing technique.  相似文献   
84.
Over the last years, the nature of service has changed owing to conceptual advances and developments in information technology. These developments have given rise to novel types of service and smart service systems (SSS), ie, resource configurations capable of learning, dynamic adaptation, and decision making. Currently, the internet of things (IoT) is turning physical objects into active smart things, bridging the gap between the physical and the digital world. Smart things advance SSS as they observe the physical environment, access local data, immerse into individuals' everyday lives and organizational routines. In line with the emergent nature of both phenomena, the impact of the IoT on SSS yet needs to be explored. Building the basis for explanatory and design‐led research and for the analysis and design of SSS, a means for the conceptual modelling of SSS that accounts for novel IoT‐enabled concepts is in high need. Hence, we designed, demonstrated, and evaluated a domain‐specific modelling language (DSML) for SSS. We evaluated the DSML by using it in the modelling of real‐world scenarios from all functional IoT domains, by submitting it to the scrutiny of industry experts, by discussing it against generic DSML requirements, and by analysing to what extent it meets domain‐specific design objectives compared with competing artefacts. To demonstrate the DSML, we included a complex real‐world scenario centred around the Nest Learning Thermostat.  相似文献   
85.
86.
Barium titanate has been prepared by solid-state reaction of nanocrystalline TiO2 (70 nm) with BaCO3 of different particle size (650, 140, and 50 nm). The results give evidence of a strong effect of the size of BaCO3 in the solid-state synthesis of barium titanate. The use of nanocrystalline BaCO3 already leads to formation of the single-phase BaTiO3 after calcination for 8 h at 800°C. The final powder consists of primary particles of ≈100 nm, has a narrow particle size distribution with d 50=270 nm, and no agglomerates larger than 800 nm. For the coarser carbonate, 4 h calcination at 1000°C are required and the final powder is much coarser. Solid-state reaction of nanocrystalline BaCO3 and TiO2 represents an alternative to chemical preparation routes for the production of barium titanate ultrafine powders.  相似文献   
87.
This contribution presents the analysis, design and characterization of a high gain Doherty power amplifier implementing an integrated Driver stage in the Auxiliary branch. Guidelines and design equations are demonstrated, fulfilling the full integration of the whole new architecture. The development of a microwave monolithic integrated circuit prototype based on TriQuint GaN technology for 7 GHz applications is reported. 10.5 dB of Gain, 38.1 dBm of saturated output power and 42% of efficiency at 7 dB of output back‐off have been demonstrated by experimental results. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:498–507, 2014.  相似文献   
88.
A novel microwave breast cancer detection system consisting of an Evolutionary Global Optimized Vivaldi antenna and an algorithm inspired by MUltiple SIgnal Classification (MUSIC) is presented. Its performance is assessed by using a simplified numerical breast phantom for a number of critical conditions including the presence of fibroglandular tissues. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.  相似文献   
89.
Approaches for improving class cohesion identify refactoring opportunities using metrics that capture structural relationships between the methods of a class, e.g., attribute references. Semantic metrics, e.g., C3 metric, have also been proposed to measure class cohesion, as they seem to complement structural metrics. However, until now semantic relationships between methods have not been used to identify refactoring opportunities. In this paper we propose an Extract Class refactoring method based on graph theory that exploits structural and semantic relationships between methods. The empirical evaluation of the proposed approach highlighted the benefits provided by the combination of semantic and structural measures and the potential usefulness of the proposed method as a feature for software development environments.  相似文献   
90.
Homotopy continuation provides a numerical tool for computing the equivalence of a smooth variety in an intersection product. Intersection theory provides a theoretical tool for relating the equivalence of a smooth variety in an intersection product to the degrees of the Chern classes of the variety. A combination of these tools leads to a numerical method for computing the degrees of Chern classes of smooth projective varieties in Pn. We illustrate the approach through several worked examples.  相似文献   
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