High temperature superconductors (HTS) in the form of REBCO (RE 1 Ba 2 Cu 3 O 7-δ ) coated conductor tapes have undergone, in recent years, major improvement of their transport current properties in ...high magnetic fields and at liquid helium temperature. The modelling of coils and other applications using REBCO tapes requires accurate characterization and precise knowledge of their properties. In this paper, we report on an anisotropic scaling law that describes the field dependence of the critical current of REBCO tapes up to the irreversibility field, <inline-formula><tex-math notation="LaTeX">{{{\bm{B}}}_{{\bm{irr}}}</tex-math></inline-formula>, and at temperatures of up to the critical temperature, <inline-formula><tex-math notation="LaTeX">{{{\bm{T}}}_{\bm{c}}}</tex-math></inline-formula>. We performed an experimental campaign to investigate the properties of recently produced commercial tapes and verify the validity of the scaling law. We measured the magnetic field dependence of the critical current in liquid helium at 4.2 K and in applied perpendicular fields of up to 15 T. The experimental setup allowed the characterization of the <inline-formula><tex-math notation="LaTeX">{{{\bm{I}}}_{\bm{c}}}</tex-math></inline-formula> of tapes up to 2.6 kA. Magnetization measurements were also used to complement the transport measurements for temperatures in the range from 4.2 K up to close to <inline-formula><tex-math notation="LaTeX">{{{\bm{T}}}_{\bm{c}}}</tex-math></inline-formula> and in background fields of up to 10.5 T.
The coronavirus D-19 (Covid-19) pandemic has shaken almost every country in the world: as we stand, 6,3 million deaths from the infection have already been recorded, 167,000 and 380,000 of which are ...in Italy and the Russian Federation, respectively. In the first wave of the pandemic, Italy suffered an abnormally high death toll. A detailed analysis of available epidemiological data suggests that that rate was shockingly high in the Northern regions and in Lombardy, in particular, whilst in the southern region the situation was less dire. This inexplicably high mortality rate in conditions of a very well-developed health care system such as the one in Lombardy - recognized as one of the best in Italy - certainly cries for a convincing explanation. In 1976, the small city of Seveso, Lombardy, experienced a release of dioxin into the atmosphere after a massive technogenic accident. The immediate effects of the industrial disaster did not become apparent until a surge in the number of tumors in the affected population in the subsequent years. In this paper, we endeavor to prove our hypothesis that the release of dioxin was a negative cofactor that contributed to a worsening of the clinical course of COVID-19 in Lombardy.
The giant cell tumor of tendon sheath (GCTTS) is the most common benign neoplasm in the hand after the ganglion cyst. Several hypotheses were formulated about the etiological factors of these tumors, ...but still there is not a common opinion on etiology, prognostic factors and recurrence rate. This article presents a review of literature of the last 15 years about GCTTS to assess the demographic, clinical and histological profile. We compared the information obtained from literature with our experience of 64 cases between 2000 and 2012. Our study showed similar results to those reported in literature, except for the recurrence rate: only 3 cases (4.7%) of 64 patients reported recurrence (versus about 15% on average in literature). Among the various possible factors that predispose to recurrence, it is necessary that the surgeon ensures complete excision of the tumor and removal of any residual satellite nodules. Although the marginal excision is the treatment of choice, it is often difficult to perform due to for the location and the strict adherence of the tumor to the tendon or neurovascular bundles. We used in all cases a magnifying loupe to help a careful research of satellite lesions and to respect surrounding structures.
Agile methods are a recent set of development techniques that apply a human-centered approach to software production. The agile approach aims to deliver high-quality products faster, producing ...satisfied customers. We conducted an empirical study to investigate whether agile methods change and improve project management practices in software companies. Survey results show that adopting agile methods appears to improve management of the development process and customer relationships. This article has given a first analysis of the advantages and disadvantages of adopting agile methods from a project management perspective.
In this paper we present a comparative analysis of the predictive power of two different sets of metrics for defect prediction. We choose one set of product related and one set of process related ...software metrics and use them for classifying Java files of the Eclipse project as defective respective defect-free. Classification models are built using three common machine learners: logistic regression, Naïve Bayes, and decision trees. To allow different costs for prediction errors we perform cost-sensitive classification, which proves to be very successful: >75% percentage of correctly classified files, a recall of >80%, and a false positive rate <30%. Results indicate that for the Eclipse data, process metrics are more efficient defect predictors than code metrics.
This paper reports on empirical research based on two software products. The research goal is to ascertain the impact of the adoption of a reuse policy on customer satisfaction. The results show that ...when a systematic reuse policy is implemented, such as the adoption of a domain specific library: reuse is significantly positively correlated with customer satisfaction; and there is a significant increase in customer satisfaction. The results have been extended to the underlying populations, supposed normal.
Haumea-one of the four known trans-Neptunian dwarf planets-is a very elongated and rapidly rotating body. In contrast to other dwarf planets, its size, shape, albedo and density are not well ...constrained. The Centaur Chariklo was the first body other than a giant planet known to have a ring system, and the Centaur Chiron was later found to possess something similar to Chariklo's rings. Here we report observations from multiple Earth-based observatories of Haumea passing in front of a distant star (a multi-chord stellar occultation). Secondary events observed around the main body of Haumea are consistent with the presence of a ring with an opacity of 0.5, width of 70 kilometres and radius of about 2,287 kilometres. The ring is coplanar with both Haumea's equator and the orbit of its satellite Hi'iaka. The radius of the ring places it close to the 3:1 mean-motion resonance with Haumea's spin period-that is, Haumea rotates three times on its axis in the time that a ring particle completes one revolution. The occultation by the main body provides an instantaneous elliptical projected shape with axes of about 1,704 kilometres and 1,138 kilometres. Combined with rotational light curves, the occultation constrains the three-dimensional orientation of Haumea and its triaxial shape, which is inconsistent with a homogeneous body in hydrostatic equilibrium. Haumea's largest axis is at least 2,322 kilometres, larger than previously thought, implying an upper limit for its density of 1,885 kilograms per cubic metre and a geometric albedo of 0.51, both smaller than previous estimates. In addition, this estimate of the density of Haumea is closer to that of Pluto than are previous estimates, in line with expectations. No global nitrogen- or methane-dominated atmosphere was detected.
In the last decade, there has been increasing interest in pair programming (PP). However, despite the existing work, there is still a lack of substantial evidence of the effects of PP in industrial ...environments. To address this issue, we have analyzed the work of a team of 17 industrial developers for 14 months. The team is part of the IT department of a large Italian manufacturing company; it adopts a customized version of extreme programming (XP). We have investigated the effects of PP on software quality in five different scenarios. The results show that PP appears to provide a perceivable but small effect on the reduction of defects in these settings.
The objective of the experiment was to compare a silage-based control diet (C) with a nonforage diet (NF) in dairy goats throughout lactation in terms of animal performance and energy utilization. ...Eight Saanen goats were divided into two groups and fed C or NF, a commercial blend that included sunflower meal, cassava, coconut meal, and whole cottonseeds as the main ingredients that was characterized by a small particle size and a high crude protein content. In early, mid, and late lactation (44, 100, and 219 days in milk) the goats were individually tested for dry matter intake (DMI), digestibility, milk yield and composition, milk renneting properties, rumen and plasma parameters, and nitrogen and energy utilization (open circuit respiration chambers). During early and mid lactation, the NF fed goats had a very high DMI: 2946 and 2915 g/ d, respectively. Nevertheless, milk yield was similar for the two treatments: 4369 vs. 4342 and 3882 vs. 3841 g/d for goats fed diets C and NF during the first and second periods, respectively. Milk fat content was not statistically different between the two diets. The protein content and rheological parameters of milk were similar for the two diets. Nonprotein nitrogen and urea levels in milk of goats fed NF were significantly higher than goats fed C. Ruminal ammonia and plasma urea nitrogen were also significantly increased by diet NF, due to its high protein content. Plasma glucose, ßbeta;-hydroxybutyrate, and nonesterified fatty acids and ruminal volatile fatty acids were not influenced by dietary treatment. Dietary NF significantly decreased energy digestibility (74.5 vs. 65.8%, on average for the lactation, for C and NF, respectively) and had a significantly lower metabolizability (metabolizable energy/intake energy; 66.6 vs 58.0%, on average); however, the efficiency of utilization of metabolizable energy was unaffected by the diet. In conclusion, goats were fed a nonforage diet during the entire lactation without detrimental effect on their health and productive performance.
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