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31.
This study aimed to apply a validated bioenergetics model of sprint running to recordings obtained from commercial basic high-sensitivity global positioning system receivers to estimate energy expenditure and physical activity variables during soccer refereeing. We studied five Italian fifth division referees during 20 official matches while carrying the receivers. By applying the model to the recorded speed and acceleration data, we calculated energy consumption during activity, mass-normalised total energy consumption, total distance, metabolically equivalent distance and their ratio over the entire match and the two halves. Main results were as follows: (match) energy consumption = 4729 ± 608 kJ, mass normalised total energy consumption = 74 ± 8 kJ · kg?1, total distance = 13,112 ± 1225 m, metabolically equivalent distance = 13,788 ± 1151 m and metabolically equivalent/total distance = 1.05 ± 0.05. By using a very low-cost device, it is possible to estimate the energy expenditure of soccer refereeing. The provided predicting mass-normalised total energy consumption versus total distance equation can supply information about soccer refereeing energy demand.  相似文献   
32.
This paper describes experiments carried out to determine the influence of dovetailed cross beams on the dimensional stability of a panel painting from the Middle Ages. Besides a serious cup (transverse distortion), the panel featured an unusual longitudinal distortion, a bow, mostly originating from bending in the proximity of the middle cross beam. Because of its localized occurrence, bending appeared to be caused by the crossbeam somehow pushing on the walls of its channel. Thanks to the cooperation offered by the curator and the restorer, some non-damaging tests were performed to measure the distortions of the panel, with and without the cross beams, after conditioning it in different climates. Processing and analysis of the measurement results demonstrated that the bow of the panel increases as the wood moisture content decreases. This led to the conclusion that the bow is actually produced by forces exerted by the cross beam along the panel's length, according to a mechanism named thrust transformation. By this mechanism the cross beam partly transforms the panel's tendency towards cupping, into a bow distortion.  相似文献   
33.
Using a new European Union-sponsored firm-level longitudinal dataset, we assess the impact of government-managed (GVC) and independent venture capital (IVC) funds on the sales and employee growth of European high-tech entrepreneurial firms. Our results show that the main statistically robust and economically relevant positive effect is exerted by IVC investors on firm sales growth. Conversely, the impact of GVC alone appears to be negligible. We also find a positive and statistically significant impact of syndicated investments by both types of investors on firm sales growth, but only when led by IVC investors. Our results remain stable after controlling for endogeneity, survivorship bias, reverse causality, anticipation effects, legal and institutional differences across countries and over time and are stable with respect to potential non-linear effects of age and size of entrepreneurial firms. Overall, our analysis casts doubt on the ability of governments to support high-tech entrepreneurial firms through a direct and active involvement in VC markets.  相似文献   
34.
Modern public transportation companies often record large amounts of information. Privacy can be safeguarded by discarding nominal tickets, or introducing anonymization techniques. But is anonymity at all possible when everything is recorded? In this paper we discuss travel information management in the public transport scenario and we present a revealing case study (relative to the city of Cesena, Italy), showing that even anonymous 10-ride bus tickets may betray a user's privacy expectations. We also propose a number of recommendations for the design and management of public transport information systems, aimed at preserving the users’ privacy, while retaining the useful analysis features enabled by the e-ticketing technology.  相似文献   
35.

Introduction:

The contamination of serum or lithium heparin blood with ethylenediaminetetraacetic acid (EDTA) salts may affect accuracy of some critical analytes and jeopardize patient safety. The aim of this study was to evaluate the effect of lithium heparin sample contamination with different amounts of K2EDTA.

Materials and methods:

Fifteen volunteers were enrolled among the laboratory staff. Two lithium heparin tubes and one K2EDTA tube were collected from each subject. The lithium-heparin tubes of each subject were pooled and divided in 5 aliquots. The whole blood of K2EDTA tube was then added in scalar amount to autologous heparinised aliquots, to obtained different degrees of K2EDTA blood volume contamination (0%; 5%; 13%; 29%; 43%). The following clinical chemistry parameters were then measured in centrifuged aliquots: alanine aminotranspherase (ALT), bilirubin (total), calcium, chloride, creatinine, iron, lactate dehydrogenase (LD), lipase, magnesium, phosphate, potassium, sodium.

Results:

A significant variation starting from 5% K2EDTA contamination was observed for calcium, chloride, iron, LD, magnesium (all decreased) and potassium (increased). The variation of phosphate and sodium (both increased) was significant after 13% and 29% K2EDTA contamination, respectively. The values of ALT, bilirubin, creatinine and lipase remained unchanged up to 43% K2EDTA contamination. When variations were compared with desirable quality specifications, the bias was significant for calcium, chloride, LD, magnesium and potassium (from 5% K2EDTA contamination), sodium, phosphate and iron (from 29% K2EDTA contamination).

Conclusions:

The concentration of calcium, magnesium, potassium, chloride and LD appears to be dramatically biased by even modest K2EDTA contamination (i.e., 5%). The values of iron, phosphate, and sodium are still reliable up to 29% K2EDTA contamination, whereas ALT, bilirubin, creatinine and lipase appear overall less vulnerable towards K2EDTA contamination.  相似文献   
36.

Background

It is still uncertain whether or not avoidance to let disinfectant alcohol dry at the site of venipuncture is a source of spurious hemolysis when drawing venous blood.

Methods:

In a consecutive series of 52 outpatients referred for routine laboratory testing, venous blood was drawn by direct venipuncture with (odd group) or without (pair group) wiping 70% isopropyl alcohol at the site of venipuncture. A 3.5 mL evacuated tube with clot activator and gel separator was drawn from a vein of the upper limb, serum was immediately separated with standard centrifugation and tested for potassium, lactate dehydrogenase (LD), aspartate aminotransferase (AST) and hemolysis index (HI) on Roche Cobas.

Results:

No specimen was discarded for unsatisfactory venipuncture. No differences for age and gender were observed between groups. As regards the four parameters investigated, no significant differences could be observed between patients in whom blood was drawn with or without letting the alcohol dry. It is also noteworthy that no sample in both groups exceeded the conventional sample rejection threshold of cell-free hemoglobin.

Conclusions:

The results of our prospective, randomized study attest that failure to wipe alcohol at the site of venipuncture should not be considered as a potential source of spurious hemolysis when drawing blood.  相似文献   
37.
Procedures involving phlebotomy are critical for obtaining diagnostic blood specimens and represent a well known and recognized problem, probably among the most important issues in laboratory medicine. The aim of this report is to show spurious hyperkalemia and hypocalcemia due to inadequate phlebotomy procedure. The diagnostic blood specimens were collected from a male outpatient 45 years old, with no clinical complaints. The tubes drawing order were as follows: i) clot activator and gel separator (serum vacuum tube), ii) K3EDTA, iii) a needleless blood gas dedicated-syringe with 80 I.U. lithium heparin, directly connected to the vacuum tube holder system. The laboratory testing results from serum vacuum tube and dedicated syringe were 4.8 and 8.5 mmol/L for potassium, 2.36 and 1.48 mmol/L for total calcium, respectively. Moreover 0.15 mmol/L of free calcium was observed in dedicated syringe. A new blood collection was performed without K3EDTA tube. Different results were found for potassium (4.7 and 4.5 mmol/L) and total calcium (2.37 and 2.38 mmol/L) from serum vacuum tube and dedicated syringe, respectively. Also free calcium showed different concentration (1.21 mmol/L) in this new sample when compared with the first blood specimen. Based on this case we do not encourage the laboratory managers training the phlebotomists to insert the dedicated syringes in needle-holder system at the end of all vacuum tubes. To avoid double vein puncture the dedicated syringe for free calcium determination should be inserted immediately after serum tubes before EDTA vacuum tubes.  相似文献   
38.
The Minerva of Arezzo is an ancient bronze statue located at the Museo Archeologico in Florence and currently under repair at the Restoration Centre of the Soprintendenza Archeologica of the Tuscany Region. We assembled a complete three-dimensional (3D) digital model of the Minerva before the restoration started. More 3D models will be produced to keep track of the variations that occurred during the restoration process, up to the final acquisition of the form of the restored artwork. The modelling of the Minerva will be the focal point of an ambitious “Minerva Project” that involves the integration of data from other sources in a 3D digital model of the object. Besides this, the project is aimed at showing how 3D techniques can be used to design useful and easily manageable new tools for the diagnostics of archaeological objects. 3D measurements have been realized by means of a high-resolution laser scanner developed at National Institute for Applied Optics (INOA). The instrument is composed of commercial low-cost components in order to be competitive with the very expensive commercial devices. Besides this, our scanner is supported by an efficient and flexible software developed by Consiglio Nazionale delle Ricerche (CNR) that supports all the post-processing phases of a 3D scanning session (range data alignment, merge and simplification).  相似文献   
39.
The research undertaken for this article aims to analyse the correspondence between perceived employability and the actual national employment rate among Italian students and graduates undertaking different courses in a large Italian university. Data were collected through a cross-sectional survey of 2087 students in 19 faculties, and compared with the national indicators of employment rate for each faculty. Using faculty as unit of analysis, the results indicated a significant correlation between participants’ perceived employability and national employment rate. This trend was similar for both genders. However, the results showed a difference between bachelor’s and master’s degrees: the correlation between perceived and actual employability was not significant among bachelor’s participants while it remained significant among master’s participants. The results suggest that graduates are only partially aware of their possibility to enter the labour market and this, in turn, highlights that universities have only partially met the goal to increase awareness about the chances of finding a job among students and graduates.  相似文献   
40.
In traditional face–to–face classrooms, collaborative learning has been endorsed as an effective pedagogy that fosters skills of analysis, communication and higher order thinking. Increasingly, as online learning environments for tertiary learners make use of course support systems, there is greater recognition of the potential of communications technologies to foster dialogue, networking and team skills among learners. Such skills are now among the recognised core attributes that graduates are expected to develop. In face–to–face classroom students learn the skills of collaboration and teamwork by engaging in tasks defined and supervised by a teacher. In online environments teacher presence is often limited to task definition, management and feedback functions. Team skills and collaboration therefore need to be supported though different pedagogies and processes such as establishing a climate of trust and openness, communication protocols, resolution of conflict and group processes that provide sanctions and support. In this paper we describe an innovative approach to building the skills of decision–making and conflict resolution, leadership and clarity in goal setting and communication. A case study of tertiary learners illustrates how the essential aspects of task definition, resources to support group learning and integrated online assessment foster team skills.  相似文献   
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