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61.
62.
It can be hypothesized that children inherit their parents' driving habits both through genetic disposition and model learning. A few studies have shown indeed that parents' and their children's traffic convictions and accidents correlate which, however, may be due to life style and other exposure factors. This study aimed at investigating the relationships between parents' and their children's self-reported driving behavior. The subjects were 174 parent-child pairs who independently completed a questionnaire. Driving behavior-driving style-was evaluated by means of Manchester driver behavior questionnaire (DBQ), while data about driving exposure, life style, accidents, and traffic tickets were also collected. A series of regression models indicated that parents' self-reported driving behavior explains their children's respective self-reported behavior, even when exposure and demographic and life-style factors are controlled. 相似文献
63.
Summary In this paper two uniqueness theorems for an anisotropic mixture of two linear elastic solids are established: The former concerns the mixed boundary-value problem, the latter the displacement problem. These theorems are proved for unbounded domains in the absence of artificial restrictions upon the behaviour of the unknown fields at infinity. A reciprocity theorem is also given. 相似文献
64.
Falcieri E Burattini S Bortul R Luchetti F Tabellini G Tazzari PL Cappellini A Cocco L Martelli AM 《Microscopy research and technique》2003,62(3):192-200
Two distinct types of cell death have been described: apoptosis and necrosis. However, it is becoming increasingly clear that the differences between these two types are far less numerous than initially thought. Morphological analyses might provide important information to distinguish apoptotic from necrotic samples. We recently reported that in necrotic, but not apoptotic, HL-60 human myeloid leukaemia cells, the nuclear protein topoisomerase IIalpha concentrated in nucleoli. In order to ascertain whether or not this phenomenon was restricted to a peculiar cell type or could be detected also in cells of lymphoid lineage, we performed an investigation aimed at defining the localization of topoisomerase IIalpha in apoptotic and necrotic Jurkat human T lymphoblastoid cells. Immunofluorescence staining demonstrated that topoisomerase IIalpha was excluded from the condensed chromatin of apoptotic cells, whereas in necrotic cells it was localized in discrete nuclear dots. Immuno-electron microscopy analysis showed that topoisomerase IIalpha was undetectable in nucleoli of normal and apoptotic cells, whereas it was present in the nucleolus of necrotic cells irrespectively of the type of inducer used (ethanol, H(2)O(2), HgCl(2)). Taken together, our findings identify topoisomerase IIalpha as a potential morphological marker useful to discriminate between apoptotic and necrotic cells. 相似文献
65.
66.
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
67.
Alessandra Orsoni 《国际通用系统杂志》2013,42(5):619-635
This paper characterizes the development of a hybrid computer-based tool supporting design for safety practices in industrial plant component specification and layout definition. The tool combines simulation and fuzzy logic techniques for the systematic risk assessment of specified design and layout configurations for plants dealing with hazardous materials. In the hybrid system architecture, the simulation module provides the historical experience for a priori hazard identification and ranking, accounting for the domino effects of possible accidental occurrences, while the fuzzy module provides the correlation matrices for concurrent hazard evaluation and overall risk assessment. In particular, the fuzzy module enables the quantitative assessment and comparison among alternative design solutions providing design guidelines, which can be further tested and verified through simulation. 相似文献
68.
This paper aims to clarify current knowledge on the contribution of communication to crisis management in the case of terrorism incidents. This is done by means of a systematic review of the scientific literature on terrorism communication over the last 10 years to identify the many challenges facing communication in such crises, and represents the first attempt of its kind. To date, within the literature on terrorism communication, much attention has been paid to chemical, biological, radiological or nuclear hazards. Terrorism crises are complex and challenging. Preparedness for such diverse low‐probability high‐impact crises can best be included in a wider educative approach. Terrorism crises call for fast information updates that, using a multi‐channel approach, can be tailored to fit different needs and (social) media habits. 相似文献
69.
Chiara Renghini Alessandra Giuliani Serena Mazzoni Francesco Brun Emanuel Larsson Francesco Baino Chiara Vitale-Brovarone 《Journal of the European Ceramic Society》2013,33(9):1553-1565
One of the key purposes of bone tissue engineering is the development of new biomaterials that can stimulate the body's own regenerative mechanism for patient's anatomical and functional recovery. Bioactive glasses, due to their versatile properties, are excellent candidates to fabricate porous 3-D architectures for bone replacement. In this work, morphological and structural investigations are carried out on Bioglass®- and CEL2-derived scaffolds produced by sponge replication (CEL2 is an experimental glass developed at Politecnico di Torino). Synchrotron radiation X-ray microtomography is used to study the samples 3-D architecture, pores size, shape, distribution and interconnectivity, as well as the growth kinetics on scaffolds struts of a newly formed apatitic phase during in vitro treatment in simulated body fluid, in order to describe from a quantitative viewpoint the bioactive potential of the analyzed biomaterials. An accurate comparison between architectural features and bioactive behaviour of Bioglass®- and CEL2-derived scaffolds is presented and discussed. 相似文献
70.
Dr. Alessandra Ammazzalorso Dr. Barbara De Filippis Dr. Letizia Giampietro Prof. Rosa Amoroso 《ChemMedChem》2013,8(10):1609-1616
Peroxisome proliferator‐activated receptors (PPARs) have been studied extensively over the last few decades and have been assessed as molecular targets for the development of drugs against metabolic disorders. A rapid increase in understanding of the physiology and pharmacology of these receptors has occurred, together with the identification of novel chemical structures that are able to activate the various PPAR subtypes. More recent evidence suggests that moderate activation of these receptors could be favorable in pathological situations due to a decrease in the side effects brought about by PPAR agonists. PPAR partial agonists and antagonists are interesting tools that are currently used to better elucidate the biological processes modulated by this family of nuclear receptors. Herein we present an overview of the various molecular structures that are able to block each of the PPAR subtypes, with a focus on promising therapeutic applications. 相似文献