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排序方式: 共有290条查询结果,搜索用时 203 毫秒
11.
M Moynahan C Mullin J Cohn CA Burns EE Halden RJ Triolo RR Betz 《Canadian Metallurgical Quarterly》1996,77(10):1005-1013
OBJECTIVE: Functional electrical stimulation (FES) is a technology that may allow some patients with spinal cord injury (SCI) to integrate standing and upright mobility with wheelchair mobility. The purpose of this study was to document the patterns of home and community use of a FES system for standing and mobility. DESIGN: A telephone questionnaire was administered every 1 to 4 weeks for a minimum of 1 year. An interview was given at the end of the study to probe the motivators and barriers to home use. SETTING: Training for use of the FES system was performed in an inpatient pediatric rehabilitation setting. Data collection began after the subjects were discharged to home. PARTICIPANTS: Five adolescents with complete, thoracic-level SCI. INTERVENTION: Subjects participated in a program of FES exercise followed by training in basic mobility skills such as standing transfers, maneuvering, level ambulation, one-handed and reaching activities, and stair ascent/descent. MAIN OUTCOME MEASURE: The frequency with which the FES system was used at home and the activities for which it was utilized were documented. Motivators and barriers to FES home use were examined. RESULTS: Subjects donned the FES system on the average once every 3 to 4 days. Between 51% and 84% of the times donned, the system was used for exercise. The remaining times it was used for standing activities, most commonly reaching, one-handed tasks, and standing for exercise. "Motivators" included being able to do things that would otherwise be difficult, perceiving a healthful benefit or a sense of well-being from standing and exercise, and feeling an obligation to stand as a participant in a research study. "Barriers" to FES use included not finding time to use the system, having difficulty seeing opportunities to stand, and being reluctant to wear the FES system all day. 相似文献
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Detection of epileptic electroencephalogram based on Permutation Entropy and Support Vector Machines 总被引:2,自引:0,他引:2
The electroencephalogram (EEG) has proven a valuable tool in the study and detection of epilepsy. This paper investigates for the first time the use of Permutation Entropy (PE) as a feature for automated epileptic seizure detection. A Support Vector Machine (SVM) is used to classify segments of normal and epileptic EEG based on PE values. The proposed system utilizes the fact that the EEG during epileptic seizures is characterized by lower PE than normal EEG. It is shown that average sensitivity of 94.38% and average specificity of 93.23% is obtained by using PE as a feature to characterize epileptic and seizure-free EEG, while 100% sensitivity and specificity were also obtained in single-trial classifications. 相似文献
14.
Whitman G.M. Pinthong C. Triolo A.A. Schwering F.K. 《Antennas and Propagation, IEEE Transactions on》2006,54(4):1111-1121
A computationally efficient method to obtain design parameters for tapered radiators is presented. The method uses a local mode theory in conjunction with the Schelkunoff equivalence principle. Radiation patterns of directive gain for dielectric wedge antennas of varying lengths and different dielectric constants are presented. Both the TE and TM cases are considered. The method is validated by comparison with data obtained from a recently developed more rigorous mode-matching method. Excellent agreement is obtained over the physically important angular range from endfire to broadside for the TE case and over the angular range spanned by the major lobe for the TM case. 相似文献
15.
Applying EuroWordNet to Cross-Language Text Retrieval 总被引:1,自引:0,他引:1
Julio Gonzalo Felisa Verdejo Carol Peters Nicoletta Calzolari 《Computers and the Humanities》1998,32(2-3):185-207
We discuss ways in which EuroWordNet (EWN) can be used in multilingual information retrieval activities, focusing on two approaches to Cross-Language Text Retrieval that use the EWN database as a large-scale multilingual semantic resource. The first approach indexes documents and queries in terms of the EuroWordNet Inter-Lingual-Index, thus turning term weighting and query/document matching into language-independent tasks. The second describes how the information in the EWN database could be integrated with a corpus-based technique, thus allowing retrieval of domain-specific terms that may not be present in our multilingual database. Our objective is to show the potential of EuroWordNet as a promising alternative to existing approaches to Cross-Language Text Retrieval. 相似文献
16.
The transformation of waste into a valuable resource is a key process towards sustainable development and green growth and therefore represents a major concern for policy-makers. Technological innovation plays a crucial role in waste management and therefore understanding the way in which regulation may spur innovation in this domain constitute is crucial. This article aims at testing the weak version of the Porter hypothesis in waste management, by analysing the dynamic relationship between the stringency of environmental regulation and innovation in a European cross-country setting. Results confirm that the stringency of regulation positively affects innovation, but the effect is non-linear, suggesting the existence of an optimal cap to the stringency of regulation. Furthermore, the overall environmental conditions of the country, as well as the presence of highly polluting sectors hinder the development of environmental innovations. 相似文献
17.
Federico Bolognesi Nicola Fazio Filippo Boriani Viscardo Paolo Fabbri Davide Gravina Francesca Alice Pedrini Nicoletta Zini Michelina Greco Michela Paolucci Maria Carla Re Sofia Asioli Maria Pia Foschini Antonietta DErrico Nicola Baldini Claudio Marchetti 《International journal of molecular sciences》2022,23(3)
Defects of the peripheral nervous system are extremely frequent in trauma and surgeries and have high socioeconomic costs. If the direct suture of a lesion is not possible, i.e., nerve gap > 2 cm, it is necessary to use grafts. While the gold standard is the autograft, it has disadvantages related to its harvesting, with an inevitable functional deficit and further morbidity. An alternative to autografting is represented by the acellular nerve allograft (ANA), which avoids disadvantages of autograft harvesting and fresh allograft rejection. In this research, the authors intend to transfer to human nerves a novel technique, previously implemented in animal models, to decellularize nerves. The new method is based on soaking the nerve tissues in decellularizing solutions while associating ultrasounds and freeze–thaw cycles. It is performed without interrupting the sterility chain, so that the new graft may not require post-production γ-ray irradiation, which is suspected to affect the structural and functional quality of tissues. The new method is rapid, safe, and inexpensive if compared with available commercial ANAs. Histology and immunohistochemistry have been adopted to evaluate the new decellularized nerves. The study shows that the new method can be applied to human nerve samples, obtaining similar, and, sometimes better, results compared with the chosen control method, the Hudson technique. 相似文献
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Nicoletta Braidotti Maria Augusta do R. B. F. Lima Michele Zanetti Alessandro Rubert Catalin Ciubotaru Marco Lazzarino Orfeo Sbaizero Dan Cojoc 《International journal of molecular sciences》2022,23(8)
The connection between cytoskeleton alterations and diseases is well known and has stimulated research on cell mechanics, aiming to develop reliable biomarkers. In this study, we present results on rheological, adhesion, and morphological properties of primary rat cardiac fibroblasts, the cytoskeleton of which was altered by treatment with cytochalasin D (Cyt-D) and nocodazole (Noc), respectively. We used two complementary techniques: quartz crystal microbalance (QCM) and digital holographic microscopy (DHM). Qualitative data on cell viscoelasticity and adhesion changes at the cell–substrate near-interface layer were obtained with QCM, while DHM allowed the measurement of morphological changes due to the cytoskeletal alterations. A rapid effect of Cyt-D was observed, leading to a reduction in cell viscosity, loss of adhesion, and cell rounding, often followed by detachment from the surface. Noc treatment, instead, induced slower but continuous variations in the rheological behavior for four hours of treatment. The higher vibrational energy dissipation reflected the cell’s ability to maintain a stable attachment to the substrate, while a cytoskeletal rearrangement occurs. In fact, along with the complete disaggregation of microtubules at prolonged drug exposure, a compensatory effect of actin polymerization emerged, with increased stress fiber formation. 相似文献
20.
Antonio Raffo Irene Baiamonte Nicoletta Nardo Flavio Paoletti 《European Food Research and Technology》2007,225(3-4):395-405
Physical (weight, firmness) and compositional (sugars, organic acids, ascorbic acid, phenolic compounds and carotenoids) changes
of red sweet peppers (Capsicum annuum L.) were monitored during 21 days of cold storage (at 7.5 °C); fruits were stored without packaging, packaged in low density
polyethylene bags, or after hot water dipping (53 °C for 4 min) and packaging. Packaging prevented water loss, and preserved
the firmness of the fresh product. Sugars (fructose and glucose) content was practically constant throughout the whole storage
time, for all treatments. A moderate accumulation of citric acid was observed during storage, but no marked effects of packaging
and hot water dipping on citric and malic acid content. Ascorbic acid content slightly increased in unpackaged and packaged
fruits, but not in treated+packaged peppers. Hydroxycinnamics total content seemed not to be affected by cold storage, packaging
or hot water treatment, whereas glycosylated flavonoids showed somewhat lowered levels during storage, particularly in the
case of unpackaged and packaged+treated fruits. Regarding carotenoids content, the effect of the considered storage conditions
seemed to be much smaller than that due to ripening stage. Provitamin A content showed an increasing trend in unpackaged and
packaged fruits; packaged+treated peppers were characterised by a lower retention of provitamin A and a higher level of capsanthin
and cucurbitaxanthin A with respect to not treated fruits. On the whole, packaging and hot water treatment did not produce
noticeable adverse effects on the majority of the examined compositional quality parameters. 相似文献