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排序方式: 共有279条查询结果,搜索用时 15 毫秒
41.
Palmar and axillary hyperhidrosis are best treated surgically by endoscopic transthoracic upper dorsal sympathectomy. At present, this methodology relies on (at least) double trocar insertion (per side), carbon dioxide insufflation, or both. We present a new minimally invasive endoscopic transthoracic technique, performed by a single-entry specifically modified thoracoscope and without the need for carbon dioxide insufflation, with the aim to reduce the drawbacks associated with the above-mentioned, currently adopted endoscopic technique. In our opinion, this "single-entry" technique, compared with the other reported approaches, should theoretically minimize any damage to the intercostal neurovascular bundle, while avoiding the complications related to carbon dioxide insufflation. 相似文献
42.
Mauro Comes Franchini Giovanni Baldi Daniele Bonacchi Denis Gentili Guido Giudetti Alessandro Lascialfari Maurizio Corti Patrick Marmorato Jessica Ponti Edoardo Micotti Uliano Guerrini Luigi Sironi Paolo Gelosa Costanza Ravagli Alfredo Ricci 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(3):366-370
43.
Edoardo Capuano Rita Boerrigter‐Eenling Grishja van der Veer Saskia M van Ruth 《Journal of the science of food and agriculture》2013,93(1):12-28
Consumers' interest in organic foods is increasing and so is the need for robust analytical tools for their authentication. This review focuses on the most promising biomarkers/analytical approaches that are available for the authentication of organic produce. Food products have been subdivided into two groups: foods of plant origin (crops) and foods of animal origin (meat, milk and dairy products, eggs and fish). For each food category the most suitable biomarkers are presented and their potential for authentication is discussed. In the light of current knowledge, it is unlikely that the authentication of organic food products can be attained by the measurement of a single marker. Analytical approaches based on the measurement of multiple markers and/or complex chemical or physical profiles/fingerprints supported by multivariate statistical analysis seem considerably more promising in this respect. For the development of robust classification models, well‐designed experimental studies must be performed that rely on data sets that are both well balanced and of sufficient size to ensure that all relevant sources of variation for the target biomarkers are included in the reference database. Copyright © 2012 Society of Chemical Industry 相似文献
44.
In a previous paper, the authors have presented a newly developed stochastic model of groundwater contaminant transport which is capable of accounting for the contribution of colloids flowing in the porous medium. The model is nonlinear and accounts explicitly for the exchange interactions among contaminants, colloids and the porous matrix, by means of properly introduced transition rates. The physical model is straightforward and intuitive, and it results in a system of differential equations whose dimensionality, in practical cases, is such to entail a Monte Carlo simulation to approach its solution. In this second part of the work, we explore in details the role played by those parameters which characterize the contaminant-colloid and the colloid-solid matrix interactions. A case study of Pu-239 transport inspired by a potential site for high level waste deposit at Mol (Belgium) is considered and the effects of colloid-facilitated transport is investigated under various conditions. Furthermore, an uncertainty analysis is performed to account for the uncertainties which in realistic situations affect the system and the transport phenomena. In this regard, a case study of Pu-239 transport inspired by the test site in Nevada has been considered. 相似文献
45.
46.
In the stone and marble industry there is considerable interest in the possibility of using ultrasound diagnostic techniques for non-destructive testing of large sized blocks in order to detect internal flaws such as faults, cracks, and fissures. In this paper we propose a specific diagnostic procedure for non-invasive, non-destructive quality control of marble blocks. Finally, the structure of a measuring set up specifically designed for in-field use is described and the experimental results are reported and discussed. 相似文献
47.
AN ENERGY ANALYSIS OF BELT POLISHING PROCESS AND ITS APPLICATIONS TO TIME CYCLE AND TRACKING EFFECTS 总被引:1,自引:0,他引:1
Edoardo Sura Mohamed El Mansori Patrick Ghidossi Stephane Deblaise Tommaso Dal Negro Hatem Khanfir 《Machining Science and Technology》2007,11(2):217-234
Belt polishing is a fine machining process widely used to improve surface texture and to increase wear resistance and fatigue life. Despite the basics of this manufacturing process are not yet well understood, the cycle-time and the belt oscillations frequency are considered as fundamental process variables. In this article, their effects on the surface characterization and on the form aspects are investigated in connection with the principal physical mechanisms activated during the superfinishing operations (cutting, ploughing and sliding). With this aim, an energy approach of the belt polishing process, coupled with SEM observations of the abrasive belt, is introduced. Two belt polishing energetic regimes are identified and then discussed. 相似文献
48.
Giovanni Fabbrocino Gerardo M. Verderame Gaetano Manfredi Edoardo Cosenza 《Engineering Structures》2004,26(14):463-2148
Structural assessment of existing reinforced concrete constructions under gravity loads and seismic actions has a high social and economical impact; actually in many European countries, most of the buildings dates back to 1960s and 1970s and cannot ensure satisfactory seismic response, since many areas have been later classified as seismic or since design has been carried out according to obsolete codes. These structures are generally reinforced with smooth bars that exhibit poor bond and need specific anchoring end details. In the present paper, some key aspects of structural models of smooth reinforcement for old-type r.c. frame analysis are reported. Results of experimental tests on smooth reinforcement and circular hook anchoring devices are also used to discuss some aspects of behavioural models of beam to column critical regions. 相似文献
49.
ABSTRACTThis paper explores the case of the historic harbour area of Naples, considered highly significant, due to its physical and cultural characteristics, with the aim of reflecting on the contemporary need for building renewed and synergic city–port relations in a sustainable perspective. Focusing on the physical and functional city–port integration, the study investigates Naples harbour planning policy between twentieth and twenty-first centuries in order to identify the limitations of older instruments and to exam the current proposal, finally suggesting perspectives for the future. The analysis highlights the fact that, in the port of Naples, with a landlord governance, the main obstacles to a more inclusive planning policy have been related to land use conflict between on one hand the public interest of the Port Authority and Municipality and the private interest of port operators on the other. In conclusion, the need for city–port plan integration is outlined as a central planning issue so as to combine the economic development of the harbour with social, cultural and ecological themes and to overcome the conflicts between the different actors involved in the complex planning process. 相似文献
50.
On‐Chip Magnetic Platform for Single‐Particle Manipulation with Integrated Electrical Feedback 下载免费PDF全文
Marco Monticelli Andrea Torti Matteo Cantoni Daniela Petti Edoardo Albisetti Alessandra Manzin Erica Guerriero Roman Sordan Giacomo Gervasoni Marco Carminati Giorgio Ferrari Marco Sampietro Riccardo Bertacco 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(7):921-929
Methods for the manipulation of single magnetic particles have become very interesting, in particular for in vitro biological studies. Most of these studies require an external microscope to provide the operator with feedback for controlling the particle motion, thus preventing the use of magnetic particles in high‐throughput experiments. In this paper, a simple and compact system with integrated electrical feedback is presented, implementing in the very same device both the manipulation and detection of the transit of single particles. The proposed platform is based on zig‐zag shaped magnetic nanostructures, where transverse magnetic domain walls are pinned at the corners and attract magnetic particles in suspension. By applying suitable external magnetic fields, the domain walls move to the nearest corner, thus causing the step by step displacement of the particles along the nanostructure. The very same structure is also employed for detecting the bead transit. Indeed, the presence of the magnetic particle in suspension over the domain wall affects the depinning field required for its displacement. This characteristic field can be monitored through anisotropic magnetoresistance measurements, thus implementing an integrated electrical feedback of the bead transit. In particular, the individual manipulation and detection of single 1‐μm sized beads is demonstrated. 相似文献