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Here we report some recent biophysical issues on the preparation of solute-filled lipid vesicles and their relevance to the construction of “synthetic cells.” First, we introduce the “semi-synthetic minimal cells” as the liposome-based cell-like systems, which contain a minimal number of biomolecules required to display simple and complex biological functions. Next, we focus on recent aspects related to the construction of synthetic cells. Emphasis is given to the interplay between the methods of synthetic cell preparation and the physics of solute encapsulation. We briefly introduce the notion of structural and compositional “diversity” in synthetic cell populations.  相似文献   
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Background: Injury of the trigeminal nerve in oral and maxillofacial surgery can occur. Schwann cell mitochondria are regulators in the development, maintenance and regeneration of peripheral nerve axons. Evidence shows that after the nerve injury, mitochondrial bioenergetic dysfunction occurs and is associated with pain, neuropathy and nerve regeneration deficit. A challenge for research is to individuate new therapies able to normalise mitochondrial and energetic metabolism to aid nerve recovery after damage. Photobiomodulation therapy can be an interesting candidate, because it is a technique involving cell manipulation through the photonic energy of a non-ionising light source (visible and NIR light), which produces a nonthermal therapeutic effect on the stressed tissue. Methods: The review was based on the following questions: (1) Can photo-biomodulation by red and NIR light affect mitochondrial bioenergetics? (2) Can photobiomodulation support damage to the trigeminal nerve branches? (preclinical and clinical studies), and, if yes, (3) What is the best photobiomodulatory therapy for the recovery of the trigeminal nerve branches? The papers were searched using the PubMed, Scopus and Cochrane databases. This review followed the ARRIVE-2.0, PRISMA and Cochrane RoB-2 guidelines. Results and conclusions: The reliability of photobiomodulatory event strongly bases on biological and physical-chemical evidence. Its principal player is the mitochondrion, whether its cytochromes are directly involved as a photoacceptor or indirectly through a vibrational and energetic variation of bound water: water as the photoacceptor. The 808-nm and 100 J/cm2 (0.07 W; 2.5 W/cm2; pulsed 50 Hz; 27 J per point; 80 s) on rats and 800-nm and 0.2 W/cm2 (0.2 W; 12 J/cm2; 12 J per point; 60 s, CW) on humans resulted as trustworthy therapies, which could be supported by extensive studies.  相似文献   
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Responds to Gauthier (see record 2004-17185-003) who commented on the two articles by Koerner et al (see record 2004-17185-001) and by Roberge et al (see record 2004-17185-002. The purpose of this response is to discuss the issue of limited availability of mental health services for anxiety disorders in Canada. From a public health perspective, the authors emphasize the importance of gathering Canadian empirical data on the organization of mental health services for anxiety disorders. Specifically more research is needed on care requirements, and the financial and structural barriers that restrict access to mental health services at the regional, provincial and national levels. The authors also discuss the role of psychologists in improving mental health care in Canada. Cost-effectiveness studies conducted in interdisciplinary practice environments could demonstrate the value added by psychology in the organization of mental health care for anxiety disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This paper introduces DILIGENT, a digital library infrastructure built by integrating digital library and Grid technologies and resources. This infrastructure allows different communities to dynamically build specialised digital libraries capable to support the entire e-Science knowledge production and consumption life-cycle by using shared computing, storage, content, and application resources. The paper presents some of the main software services that implement the DILIGENT system. Moreover, it exemplifies the provided features by presenting how the DILIGENT infrastructure is being exploited in supporting the activity of user communities working in the Earth Science Environmental sector. This work is partially funded by the European Commission in the context of the DILIGENT project, under the 2nd call of FP6 IST priority.  相似文献   
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A comparative analysis of methods for pruning decision trees   总被引:14,自引:0,他引:14  
In this paper, we address the problem of retrospectively pruning decision trees induced from data, according to a top-down approach. This problem has received considerable attention in the areas of pattern recognition and machine learning, and many distinct methods have been proposed in literature. We make a comparative study of six well-known pruning methods with the aim of understanding their theoretical foundations, their computational complexity, and the strengths and weaknesses of their formulation. Comments on the characteristics of each method are empirically supported. In particular, a wide experimentation performed on several data sets leads us to opposite conclusions on the predictive accuracy of simplified trees from some drawn in the literature. We attribute this divergence to differences in experimental designs. Finally, we prove and make use of a property of the reduced error pruning method to obtain an objective evaluation of the tendency to overprune/underprune observed in each method  相似文献   
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Abdominal aortic dissection is a rare pathology. As far as we are concerned, only 59 cases have been reported in the English literature. In the last two years, two cases were treated at our Institution. Both were males, over 70 years of age. They were evaluated with ultrasonography, angiography (1 case) and Magnetic Resonance Imaging which showed localised dissection of the abdominal aorta with aneurysmal dilatation. They underwent surgical treatment with good results. At 1 and 2 years from operation both patients are alive and well. A postoperative ultrasonography didn't show any residual dissection.  相似文献   
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