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121.
Massimo Giusti Mara Dolcino Lara Vera Carla Ghiara Francesca Massaro Laura Fazzuoli Diego Ferone Michele Mussap Francesco Minuto 《Journal of Zhejiang University. Science. B》2009,10(5):323-330
Assaying parathyroid hormone (PTH) in the washing liquid after fine-needle aspiration biopsy (FNAB) seems to be a valid approach to locate parathyroid tissue. PTH-FNAB was evaluated in 47 patients with a clinical picture of primary hyper-parathyroidism (PHP) and ultrasonography (US) suggestive of parathyroid lesion. The patients were subdivided into two groups on the basis of the absence or presence of US thyroid alterations. The result of PTH-FNAB was compared with those of cytology, scintigraphy and, in 24 patients, surgical outcome. PTH-FNAB samples with a value higher than that recorded in the serum and higher than our institutional cut-off were deemed to be probable samples of parathyroid tissue. Cytology proved diagnostic for benign thyroid lesions, non-diagnostic for thyroid lesions, hyperplastic parathyroid tissue, undetermined or malignant thyroid lesions and other lesions in 45%, 30%, 17%, 4%, and 4% of cases, respectively. In 47% of cases, PTH-FNAB indicated that the sample had been taken in parathyroid tissue. In patients without US alterations, the diagnostic accuracy of PTH-FNAB was greater than that of scintigraphy. After surgery, comparison between the results of PTH-FNAB and scintigraphy, in terms of positive predictive value (PPV), revealed the superiority of PTH-FNAB; PPV was 94% for FNAB and 71% for scintigraphy, while sen-sitivity was 83% and 69%, respectively. PTH-FNAB evaluation after FNAB appears to be more diagnostic than cytology and scintigraphy. Of all the procedures used, PTH-FNAB appears to be the method of choice when the target is US suggestive and reachable. PTH-FNAB appears to be a useful method of guiding surgical intervention. 相似文献
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123.
Johnny Padulo Giuseppe Attene Gian Mario Migliaccio Francesco Cuzzolin Stefano Vando 《Journal of sports sciences》2015,33(14):1454-1458
The free throw (FT) is a fundamental basketball skill used frequently during a match. Most of actual play occurs at about 85% of maximum heart rate (HR). Metabolic intensity, through fatigue, may influence a technically skilled move as the FT is. Twenty-eight under 17 basketball players were studied while shooting FTs on a regular indoor basketball court. We investigated FT accuracy in young male basketball players shooting at three different HRs: at rest, at 50% and at 80% of maximum experimentally obtained HR value. We found no significant FT percentage difference between rest and 50% of the maximum HR (FT percentage about 80%; P > 0.05). Differently, at 80% of the maximum HR the FT percentage decreased significantly by more than 20% (P < 0.001) down to about 60%. No preliminary warm-up is needed before entering game for the FT accuracy. Furthermore, we speculate that time-consuming, cooling-off routines usually performed by shooters before each FT may be functional to improve its accuracy. 相似文献
124.
Gianfranco Gagliardi Francesco Tedesco Alessandro Casavola 《Journal of The Franklin Institute》2018,355(14):6710-6745
This paper illustrates the derivation of a linear parameter varying (LPV) model approximation of a turbocharged Spark-Ignition (SI) automotive engine and its usage in designing a model-based fault detection and isolation (FDI) scheme. The LPV approximation is derived from a detailed nonlinear mathematical model of the engine on the basis of the well known Jacobian approach. The resulting LPV representation is then exploited for synthesizing a bank of LPV-FDI Luenberger observers. Each observer is in charge of detecting a particular class of fault and is designed for having low sensitivity to all other exogenous inputs so as to allow an effective fault isolation. The adopted FDI scheme is gain-scheduled and exploits a set of engine variables, assumed to be measurable on-line, as a scheduling parameters. The goodness of the LPV approximation of the engine model and the effectiveness of the LPV-FDI architecture are demonstrated by several numerical simulations. 相似文献
125.
Martin Kokholm Fleron Niels Christian Hauerbach Ubbesen Francesco Battistella David Leandro Dejtiar 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(4):366-377
Motion capture through inertial sensors is becoming popular, but its accuracy to describe kinematics during changes in walking speed is unknown. The aim of this study was to determine the accuracy of trunk speed extracted using an inertial motion system compared to a gold standard optical motion system, during steady walking and stationary periods. Eleven participants walked on pre-established paths marked on the floor. Between each lap, a 1-second stationary transition period at the initial position was included prior to the next lap. Resultant trunk speed during the walking and transition periods were extracted from an inertial (240 Hz sampling rate) and an optical system (120 Hz sampling rate) to calculate the agreement (Pearson’s correlation coefficient) and relative root mean square errors between both systems. The agreement for the resultant trunk speed between the inertial system and the optical system was strong (0.67 < r ≤ 0.9) for both walking and transition periods. Moreover, relative root mean square error during the transition periods was greater in comparison to the walking periods (>40% across all paths). It was concluded that trunk speed extracted from inertial systems have fair accuracy during walking, but the accuracy was reduced in the transition periods. 相似文献
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127.
Nasser Abu Zeid Marco Balducci Francesco Bartocci Roberto Regni Giovanni Santarato 《Journal of Cultural Heritage》2010,11(2):220-227
The electrical resistivity tomography (ERT) represents one of the widely used geophysical techniques for the exploration of the subsurface. In the last few years, this method has been demonstrated to be an efficient reconnaissance tool not only for monitoring degradation status of walls and foundations of historical buildings, but also for imaging the spatial distribution of injected mortar, commonly employed for consolidation purposes. A 3D resistivity tomography survey was carried out on four selected wall portions of the historical church of Montepetriolo, Perugia, Central Italy. The obtained 3D resistivity distribution models before and after grouting provided suggestive images of the internal structure of the studied walls. Moreover, the spatial distribution of the zones being filled with mortar was determined quantitatively by scaling the post- to the preinjection resistivity values. Using a well known correlation between resistivity and porosity, established in the geophysical community, a further step towards a more quantitative assessment was attempted to indirectly determine the unit volumes of the injected mortar The obtained results were satisfactory and in some cases almost similar to the yard data. Furthermore, two flat-jack tests confirmed the local increment of the mechanical resistance of the studied left front (2) and right lateral (3) wall portions. 相似文献
128.
Ella James-Brabham Toni Loveridge Francesco Sella Paul Wakeling Daniel J. Carroll Emma Blakey 《Child development》2023,94(6):1550-1565
Socioeconomic attainment gaps in mathematical ability are evident before children begin school, and widen over time. Little is known about why early attainment gaps emerge. Two cross-sectional correlational studies were conducted in 2018–2019 with socioeconomically diverse preschoolers, to explore four factors that might explain why attainment gaps arise: working memory, inhibitory control, verbal ability, and frequency of home mathematical activities (N = 304, 54% female; 84% White, 10% Asian, 1% black African, 1% Kurdish, 4% mixed ethnicity). Inhibitory control and verbal ability emerged as indirect factors in the relation between socioeconomic status and mathematical ability, but neither working memory nor home activities did. We discuss the implications this has for future research to understand, and work towards narrowing attainment gaps. 相似文献
129.
Megan Foulkes Francesco Sella Theresa Elise Wege Camilla Gilmore 《Mind, Brain, and Education》2023,17(3):185-196
There is mixed evidence as to whether concrete manipulatives (e.g., toy animals) are better than abstract manipulatives (e.g., counters) for teaching mathematical concepts to children. Concreteness is defined as the amount of extraneous information a manipulative provides, and in this study we aimed to unpick which dimensions of concreteness influence manipulative choice. Researchers, teachers, and parents completed a comparative judgment task comparing images of manipulatives varying in different dimensions of concreteness, selecting which they would choose to teach arithmetic to children. The findings indicated homogeneous, 3-dimensional manipulatives were the most preferred across all groups to teach arithmetic to children, regardless of more extraneous features. This contradicts research recommendations to minimize the use of concrete manipulatives due to their distractive qualities. Instead, it suggests that some concrete features may be preferred in more naturalistic contexts. More research is required to investigate how different dimensions of concreteness influence learning outcomes for children both in artificial research contexts and in practice. 相似文献