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1.
Cloning of observables, unlike standard cloning of states, aims at copying the information encoded in the statistics of a class of observables rather then on quantum states themselves. In such a process the emphasis is on the quantum operation (evolution plus measurement) necessary to retrieve the original information. We analyze, for qubit systems, the cloning of a class generated by two noncommuting observables, elucidating the relationship between such a process and joint measurements. This helps in establishing an optimality criterion for cloning of observables. We see that, even if the cloning machine is designed to act on the whole class generated by two noncommuting observables, the same optimal performances of a joint measurement can be attained. Finally, the connection with state dependent cloning is enlightened.  相似文献   
2.
Flow cytometry is a unique technology useful in the examination of effects of immunotoxic agents on target cells of the immune system. The purpose of this workshop was to provide an overview of the use of flow cytometry in new and established models of immunotoxicity, with emphasis on the potential applications, assay validation, and potential pitfalls. This overview begins with a discussion of methods useful in the assessment of Ca2+-dependent mechanisms of lymphoid cell activation in surface marker-defined human B cells, T cells, and monocytes. A discussion of the use of flow cytometry in analysis of apoptosis is also presented in this paper. The second paper presents data on the development and use of flow cytometry as an alternative to a Cr51 release assay for an assessment of cytotoxic T cell activation. The use of surface markers for characterizing and distinguishing the effects of chemical irritants from sensitizers is next presented, followed by an overview of the use of fluorescent probes to assess cell thiol status and overall oxidant-induced injury to lymphoid cells. Finally, an interlaboratory study designed to compare and evaluate the use of flow cytometry procedures in rat splenic cell subtyping is presented. Overall, these studies demonstrate the utility of flow cytometry assays in immunotoxicologic research, but further efforts are needed in the validation of many of these assays for routine use in immunotoxicologic testing.  相似文献   
3.
Lipofilling (LF) is a largely employed technique in reconstructive and esthetic breast surgery. Over the years, it has demonstrated to be extremely useful for treatment of soft tissue defects after demolitive or conservative breast cancer surgery and different procedures have been developed to improve the survival of transplanted fat graft. The regenerative potential of LF is attributed to the multipotent stem cells found in large quantity in adipose tissue. However, a growing body of pre-clinical evidence shows that adipocytes and adipose-derived stromal cells may have pro-tumorigenic potential. Despite no clear indication from clinical studies has demonstrated an increased risk of cancer recurrence upon LF, these observations challenge the oncologic safety of the procedure. This review aims to provide an updated overview of both the clinical and the pre-clinical indications to the suitability and safety of LF in breast oncological surgery. Cellular and molecular players in the crosstalk between adipose tissue and cancer are described, and heterogeneous contradictory results are discussed, highlighting that important issues still remain to be solved to get a clear understanding of LF safety in breast cancer patients.  相似文献   
4.
Program verification and testing techniques are crucial in fruitfully analyzing and validating complex software systems. This is an active research area and has produced various promising techniques in the last decade. However, many challenges lie ahead. We review the research area and summarize six papers selected from the Sixth International Symposium on Theoretical Aspects of Software Engineering (TASE 2012).  相似文献   
5.
We show on a case study from an autonomous aerospace context how to apply a game-based model-checking approach as a powerful technique for the verification, diagnosis, and adaptation of system behaviors based on temporal properties. This work is part of our contribution within the SHADOWS project, where we provide a number of enabling technologies for model-driven self-healing. We propose here to use GEAR, a game-based model checker, as a user-friendly tool that can offer automatic proofs of critical properties of such systems. Although it is a model checker for the full modal μ-calculus, it also supports derived, more user-oriented logics. With GEAR, designers and engineers can interactively investigate automatically generated winning strategies for the games, by this way exploring the connection between the property, the system, and the proof. This work has been partially supported by the European Union Specific Targeted Research Project SHADOWS (IST-2006-35157), exploring a Self-Healing Approach to Designing cOmplex softWare Systems. The project’s web page is at . This article is an extended version of Renner et al. [18] presented at ISoLA 2007, Poitiers, December 2007.  相似文献   
6.
XGC1 and M3D-C 1 are two fusion plasma simulation codes being developed at Princeton Plasma Physics Laboratory. XGC1 uses the particle-in-cell method to simulate gyrokinetic neoclassical physics and turbulence (Chang et al. Phys Plasmas 16(5):056108, 2009; Ku et al. Nucl Fusion 49:115021, 2009; Admas et al. J Phys 180(1):012036, 2009). M3D-\(C^1\) solves the two-fluid resistive magnetohydrodynamic equations with the \(C^1\) finite elements (Jardin J comput phys 200(1):133–152, 2004; Jardin et al. J comput Phys 226(2):2146–2174, 2007; Ferraro and Jardin J comput Phys 228(20):7742–7770, 2009; Jardin J comput Phys 231(3):832–838, 2012; Jardin et al. Comput Sci Discov 5(1):014002, 2012; Ferraro et al. Sci Discov Adv Comput, 2012; Ferraro et al. International sherwood fusion theory conference, 2014). This paper presents the software tools and libraries that were combined to form the geometry and automatic meshing procedures for these codes. Specific consideration has been given to satisfy the mesh configuration and element shape quality constraints of XGC1 and M3D-\(C^1\).  相似文献   
7.
An ac brushless drive in which Hall-effect sensors are used as rotor position sensors is presented in this paper. Three different methods to obtain a high-resolution position estimation from the low-resolution sensors are described and compared through simulation and experimental testing. The proposed control algorithm's most innovative feature is its adaptability to the entire speed range, including startup, when using any of the three estimation algorithms. The control algorithm has been implemented and tested in order to drive a slotless axial-flux permanent-magnet (PM) machine for domestic appliance applications.  相似文献   
8.
This special section is devoted to some of the novel approaches to hardware-like system verification that are currently being used in industry or the object of fielded research. The topics presented in this special section are based on a selection of the papers which appeared originally in the Proceedings of CHARME 2001, the Eleventh Advanced Research Working Conference on Correct Hardware Design and Verification Methods which took place in Livingston, Scotland, UK in September 2001. They are by no means a complete account of the numerous ways in which hardware and hardware-like systems are being subject to rigorous investigation, but they represent an interesting sample of today’s problems and of the techniques oriented around new uses of verification techniques. Published online: 10 April 2003  相似文献   
9.
Anderson–Fabry disease (FD) is an X-linked disease caused by a functional deficit of the α-galactosidase A enzyme. FD diagnosis relies on the clinical manifestations and research of GLA gene mutations. However, because of the lack of a clear genotype/phenotype correlation, FD diagnosis can be challenging. Recently, several studies have highlighted the importance of investigating DNA methylation patterns for confirming the correct diagnosis of different rare Mendelian diseases, but to date, no such studies have been reported for FD. Thus, in the present investigation, we analyzed for the first time the genome-wide methylation profile of a well-characterized cohort of patients with Fabry disease. We profiled the methylation status of about 850,000 CpG sites in 5 FD patients, all carrying the same mutation in the GLA gene (exon 6 c.901C>G) and presenting comparable low levels of α-Gal A activity. We found that, although the whole methylome profile did not discriminate the FD group from the unaffected one, several genes were significantly differentially methylated in Fabry patients. Thus, we provide here a proof of concept, to be tested in patients with different mutations and in a larger cohort, that the methylation state of specific genes can potentially identify Fabry patients and possibly predict organ involvement and disease evolution.  相似文献   
10.
Prostate cancer (PCa) ranges from indolent to aggressive tumors that may rapidly progress and metastasize. The switch to aggressive PCa is fostered by reactive stroma infiltrating tumor foci. Therefore, reactive stroma-based biomarkers may potentially improve the early detection of aggressive PCa, ameliorating disease classification. Gene expression profiles of PCa reactive fibroblasts highlighted the up-regulation of genes related to stroma deposition, including periostin and sparc. Here, the potential of periostin as a stromal biomarker has been investigated on PCa prostatectomies by immunohistochemistry. Moreover, circulating levels of periostin and sparc have been assessed in a low-risk PCa patient cohort enrolled in active surveillance (AS) by ELISA. We found that periostin is mainly expressed in the peritumoral stroma of prostatectomies, and its stromal expression correlates with PCa grade and aggressive disease features, such as the cribriform growth. Moreover, stromal periostin staining is associated with a shorter biochemical recurrence-free survival of PCa patients. Interestingly, the integration of periostin and sparc circulating levels into a model based on standard clinico-pathological variables improves its performance in predicting disease reclassification of AS patients. In this study, we provide the first evidence that circulating molecular biomarkers of PCa stroma may refine risk assessment and predict the reclassification of AS patients.  相似文献   
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