Educational efficiency in a dea-bootstrap approach

We use the PISA 2006 results to analyse the students' proficiencies in 24 European Countries with regard to two indexes that represent the educational resources available at home and the family background of students. Many factors affect the proficiencies and therefore, using a DEA-bootstrap method, we intend to measure the efficiency of the European educational systems as capability to ensure high students' competencies despite adverse conditions about the educational resources available in students' home and the family background.PISA, educational achievement, efficiency analysis.

An extension of Lorentz's almost convergence and applications in Banach spaces

2000 Mathematics Subject Classification: Primary 40C99, 46B99.We investigate an extension of the almost convergence of G. G. Lorentz requiring that the means of a bounded sequence converge uniformly on a subset M of N. We also present examples of sequences α∈ l∞(N) whose sequences of translates (Tn α)n≥ 0 (where T is the left-shift operator on l∞(N)) satisfy: (a) Tn α, n ≥ 0 generates a subspace E(α) of l∞(N) that is isomorphically embedded into c0 while α is not almost convergent. (b) Tn α, n ≥ 0 admits an l1-subsequence and a nontrivial weakly Cauchy subsequence while a is almost convergent. Finally we show that, in the sense of measure, for almost all real sequences taking values in a compact set K ⊆ R (with at least two points), the sequence (Tn α)n ≥ 0 is equivalent in the supremum norm to the usual l1-basis and (hence) not almost convergent

Cardiac Tamponade Secondary to Metastasis from Adenocarcinoma of the Parotid Gland

BACKGROUND: Metastatic involvement of pericardium producing cardiac tamponade is rare. When occurs it is mainly from the lung, breast and the neoplasms of the lymphoreticular system. Hematogenous spread of parotid adenocarcinoma to heart is extremely rare and only two cases have been reported in literature so far. CASE PRESENTATION: We report an unusual case of a patient with adenocarcinoma of the parotid gland, which presented with cardiac tamponade and was treated urgently with pericardial drainage and intrapericardial injection of cisplatin. CONCLUSIONS: Our case demonstrates the possibility of metastatic pericardial involvement and cardiac tamponade in patients with parotid adenocarcinoma. The patient was successfully treated with pericardial drainage and intrapericardial injection of chemotherapeutic agent to control recurrent pericardial effusion

Application of a virtual scientific experiment model in different educational contexts

E-learning practice is continuously using experimentation in order to enhance the basic information transfer model where knowledge is passed from the system/ tutors to the students. Boosting student productivity through on-line experimentation is not simple since many organizational, educational and technological issues need to be dealt with. This work describes the application of a Learning Model for Virtual Scientific Experiments (VSEs) in two different scenarios: Information and Communication Technologies and Physics. As part of the first, a VSE for Wireless Sensor Networks was specified and deployed while the second involved the specification and design of a collaborative VSE for physics experiments. Preliminary implementation and deployment results are also discussed

A Peer-to-Peer Agent Auction

In this work we examine a peer-to-peer agent continuous double auction. We compare agents trading using peer-to-peer communications with agents using the same trading strategy in an auction that makes use of a centralized auctioneer to disseminate information. We present simulation data for these two auctions running with 2,500 to 160,000 agents. We find that the peer-to-peer auction is able to display price convergence behavior similar to that of the centralized auction. Further, the data shows that the peer-to-peer system has a constant cost in the number of message rounds needed to find the market equilibrium price as the number of traders is increased, in contrast to the linear cost incurred by the central auctioneer. Considering the above message costs, the peer-to-peer system outperformed the simple central auction by at least 100 times in our simulations. We further calculate that for a distributed hierarchical set of auctioneers, for which the message rounds cost of finding equilibrium are reduced to logarithmic in the number of traders, the peer-to-peer system will still produce better performance for systems with more than 5,000 traders

Laparoscopic totally extraperitoneal inguinal hernia repair in the elderly: A prospective control study

Inguinal hernia (IH) repair can be obtained with both open and laparoscopic techniques, which are usually performed using a transabdominal preperitoneal (TAPP) or a totally extraperitoneal (TEP) approach. The aim of the study was to evaluate whether the results of laparoscopic TEP IH repair in the elderly ( 6565 years old) are different with respect to results obtained in younger patients. One hundred and four consecutive patients (four women and 100 men, median age of 57 years, range=21-85 years) with unilateral (N=21, 20.2%) or bilateral (N=83, 79.8%) IH were prospectively enrolled in the study. Patients were divided into two groups according to their age: group A (N=68, 65.4%) aged <65 years and group B (N=36, 34.6%) aged 6565 years. The mean operative time was not significantly different between groups (48\ub120 vs. 52\ub120 min, p=0.33). One case of increased PaCO2 was observed in each group (p=0.72) and two and one case of pneumoperitoneum (p=0.57) in groups A and B, respectively. Two (1.9%) patients (one in each group; p=0.55) required TEP conversion. Mild postoperative complications developed in four patients of each group (p=0.44). After one-year follow-up, three (2.9%) recurrences occurred (group 1=1, group 2=2, p=0.55), both in patients who had undergone direct IH repair. The overall postoperative relative risk of complications related to age was 1.08 (95% confidence interval=0.91-1.27, p=0.53). In conclusion, our results suggest that in patients with IH scheduled for TEP repair, age does not represent a contraindication to surgery in terms of complication rate and postoperative results