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To assess the incidence of a specific etiology and the role of methods for specific etiologic diagnosis in patients with primary acute pericarditis, we studied 100 patients with primary acute pericarditis consecutively admitted to our hospital between 1991 and 1993. A general diagnostic protocol was performed in all patients, whereas only pericardiocentesis was performed in patients with clinical cardiac tamponade or an unfavorable course with anti-inflammatory drugs. Surgical drainage and pericardial biopsy was performed in patients with tamponade relapse. A specific etiology was discovered in 22 patients (22%) (neoplasms in 7, tuberculosis in 4, other infections in 3, collagen diseases in 3, thyroid disorders in 4, and dissecting aortic aneurysm in 1). The general diagnostic protocol led to a specific diagnosis in 15 patients (68% of all patients with specific acute pericarditis) and pericardiocentesis in the other 7 patients (32%). The role of a diagnostic protocol, therapeutic pericardiocentesis, and diagnostic pericardiocentesis was similar and complementary. Pericardial biopsy results were negative in the 5 patients in whom it was performed. Cardiac tamponade and an unfavorable clinical outcome were significantly (p < 0.001) associated with the finding of a specific etiology; when both features were combined, sensitivity was 86% and specificity 85%, positive predictive value 63% and negative predictive value 96%. We conclude that the specific etiology in patients with primary acute pericarditis is about 20% to 25%, and that about 90% of these specific cases can be discovered by using the described systematic diagnostic protocol only in patients with an unfavorable outcome (cardiac tamponade or poor clinical course).

ENRESA is the National Spanish Agency responsible of the dismantling of Nuclear Facilities, previous Transfer of ownership of the facility from the Utility to ENRESA. On April 30th 2006, Jose´ Cabrera Nuclear Power Plant (Fig. 1) was definitively shutdown, and two years later, on April 30th 2008, ENRESA requested the transfer of the ownership of the Plant from the Ministry along with the corresponding authorization for performance of the Dismantling and Decommissioning Plan. On February 1st 2010, ENRESA was authorized to initiate the dismantling of Jose´ Cabrera NPP, once the spent fuel has been stored on-site at a dry storage facility (ISFSI). Currently, preparatory activities are underway, including the modification of systems and auxiliary facilities for waste and material management. Main challenges of the project include the removal of major components (vessel, steam generator, pressurizer, main pump and primary loop), and the use of large containers (CE-2b) to reduce segmentation of activated parts.

Learning and teaching procedures need to evolve, regarding the high technological profile most students have. The Teacher might consider that in some cases, outdated teaching methods create barriers for students who are used to interaction with modern technological gadgets and computers. Augmented Reality technology emerges as a great potential tool in the teaching environment. Augmented reality (AR) is a cost-effective technology which has the ability to coexist with paper books supplying students with more attractive and didactic contents meaning rebirth of classic textbooks. In this work we present the developed didactic material supported by AR technology for learning sketching, designation and rules of standard mechanical elements. This book has been included in the curriculum of engineering graphics subject of the Mechanical Engineering Degree in a Spanish University for performing a pilot study seeking comparison of academic performance acquired and motivation for study between two groups of students. One group uses AR based material meanwhile the other uses traditional class notes.Copyright © 2011 by ASME

The use of statistical tools to improve the decision process within leak detection is becoming a common practice in the area of computer pipeline monitoring. Among these tools, the sequential probability ratio test is one of the most named techniques used by commercial leak detection systems (Zhang and Di Mauro, 1998, “Implementing a Reliable Leak Detection System on a Crude Oil Pipeline,” Advances in Pipeline Technology, Dubai, UAE). This decision mechanism is based on the comparison of the estimated probabilities of leak or no leak observed from the pipeline data. This paper proposes a leak detection system that uses a simplified statistical model for the pipeline operation, allowing a simple implementation in the pipeline control system (Di Blasi, M., 2004, “Detección y localización de fugas en sistemas de transporte de fluidos incompresibles,” MS thesis, Universidad Nacional de La Plata, Buenos Aires, Argentina). Applying real-time recursive linear regression to volume balance and average pipeline pressure signals, a statistically corrected volume balance signal with reduced variance is derived. Its average value is zero during normal operation whereas it equals the leak flow under a leak condition. Based on the corrected volume balance, differently configured sequential probability ratio tests are presented to extend the dynamic range of detectable leak flow. Simplified mathematical expressions are obtained for several system performance indices, such as spilled volume until detection, time to leak detection, minimum leak flow detected, etc. Theoretical results are compared with leak simulations on a real oil pipeline. A description of the system tested over a 500 km oil pipeline is included, showing some real data results.

Nowadays, the use of the Finite Element Method [1] by means of simulation computer tools has made possible a substantial step forward in the field of calculation and optimization of vehicle structures. More specifically, these modern calculation tools are achieving great cost reductions corresponding to the experimental tests necessary to verify the appropriate performance of a vehicle in impact cases. On the other hand, great efforts will have to be done to develop correct numerical models for calculation. Once these numerical models have been validated with experimental tests, elimination of experimental costs compensates for these calculation efforts. A greater flexibility in decision making with respect to design and optimization alternatives will be achieved as well. The objective of this paper is to obtain an appropriate test simulation methodology for a specific vehicle and a specific impact case: There have been carried out the simulations of two different rollover test typologies in order to verify an adequate and safe behaviour of a semitrailer designed for hydrogen transport. After results of these two simulations are obtained, they will be compared in order to set which is the most restrictive and therefore the most appropriate. A lightened configuration has been also considered so as to carry out a sensibility analysis of material and thickness of some structural parts over numerical results in both test typologies in order to verify these simulations.Copyright © 2009 by ASME

In this paper, a new concept of rear bumper for semi trailer has been developed by means of numerical simulation. A semi trailer bumper is a substructure that has a great importance in the whole vehicle. It reduces the effect of a crash impact against another vehicle in the rear part of the semi trailer. Thus, both the vehicle and passengers are protected from impact effects. The design of this kind of structures must show suitable behavior depending upon crash conditions and structure conditions (bumper material, load cases, boundary conditions, impact velocity[[ellipsis]]). In this study case, 79/490/CEE Directive shows the specific conditions that must be complied by a rear protective device to be approved by an official certifying body. The bumper design has been carried out by means of numerical simulation tools based on the Finite Element Method (FEM). This method provides results in terms of strain and stress of the analyzed structures, subjected to several load cases, boundary conditions, and considering several materials. A new light aluminum bumper structure fulfilling the previous directive is obtained. Finally, a light bumper prototype has been developed based on the previous numerical results and it has been tested according to the homologation conditions specified in 79/490/CEE Directive. Nowadays, Lecitrailer S.A., a Spanish semi trailers manufacturer, has incorporated this new bumper structure to their vehicles.Copyright © 2007 by ASME

The design and optimization of a continuous flow solar water disinfection device is presented. The design is based on a batch disinfector, previously tested and reported, in which water was exposed to solar radiation in plastic bottles. In the new device, water flows through a plastic pipe exposed to solar radiation. The flow control is accomplished by using a solenoid valve, which permits the flow of water only when the solar radiation reaches a minimum predetermined value. In the optimization analysis, the tubing’s diameter and length-width ratio of the irradiation zone were optimized to obtain the maximum flow at the exposure time required to obtain water disinfection. External flat reflecting surfaces concentrate the incoming solar radiation over the receiving area, in order to reduce the residence time required to guarantee complete water disinfection.Copyright © 2006 by ASME

The use of leak detection and location systems has became a common practice in the control rooms of pipeline operations, whereby operators are automatically alerted of a leak, and informed of its approximate location. Considerable attention has primarily been paid to leak sensitivity and leak detection time. However, this paper shows that in long pipelines the volume lost after a pipeline shutdown can be substantially more than what was lost prior to the detection. In very irregular altimetry, the drainage from the pipeline segment can represent a greater volume of spillage as compared to the spillage from the start of the leak until its detection. These volumes can be reduced by taking the appropriate actions. This work will illustrate the importance of having a leak contingency plan that orients the operators to take suitable actions that will diminish the volume spilled. A leak contingency plan is a detailed plan of recommended actions, for example valve closure and pumping shutdown, and the specific time sequence in which they have to be executed. The design of these plans was based on the use of hydraulic transient simulations of an actual 3000-km network in Argentina.Copyright © 2006 by ASME

A novel leak localization method for multi section pipelines is presented. Based on normal operation flowing thermodynamic pressure drop patterns along the pipeline, the system continuously compares with the measured pressure drops, and makes a decision based on the best fit finding the section where the leak occurs. A statistical approach is used accounting for noisy measured signals. The method uses steady state fluid equations, a recursive parameter estimation algorithm, and statistical decision and pattern recognition techniques. A modification is introduced to consider the cost of making a wrong leaky section choice in terms of the excess volume spilled due to gravitational flow after pipeline shut down. This leads to a Bayesian decision scheme minimizing a risk functional. The costs are the spill volumes, obtained from dynamical simulation of the pipeline, under the various possible decision scenarios. Finally, details are given of the successful implementation of the system on a 500km long oil pipeline, and real data from a simulated leak experiment are shown.

A flow-induced vibration problem evaluation of a shell and tube cooling water heat exchanger equipment installed in a power plant is presented in this paper. The problem produced loss of thickness in many tubes of the bundle, by impact or fretting wear, and the need to plug these tubes to avoid leakage. These vibrations could had been produced by changes in the equipment operational conditions or by a wrong evaluation during the design stage. An analytical and experimental evaluation was made to predict tubes dynamical response and to identify the excitation mechanisms. The original design modification adopted to solve the problem is presented and evaluated.Copyright © 2002 by ASME

Objectives: GO is a conjugate of calicheamicin and a monoclonal antibody that targets CD33+ myeloblasts in acute myeloid leukemia (AML). After GO administration, ascites, weight gain, elevated aminotransferase enzymes, and jaundice (Sinusoidal Obstruction Syndrome, SOS, formerly known as VOD) have been reported. After approval by the FDA for relapsed AML in 2000 and its introduction into routine clinical practice, the incidence of SOS after GO infusion has been the subject of debate. The objectives of this study were to estimate the incidence rate of SOS after GO infusion in routine clinical practice, identify risk factors associated with the development of SOS, describe the incidence rates of serious adverse events (SAEs) and nonserious adverse events of special interest (ESIs). Methods: This study was a prospective observational study that enrolled consenting patients who were to receive GO for AML, with assessments at baseline, weekly x6 after the 1st dose of GO or 4 weeks after the last dose (whichever was later), and at 6 months. There were no exclusion criteria. Two hepatologists (GBM, LDD) reviewed cases with liver abnormalities and classified patients as either SOS, liver disease unlikely to be SOS, or no SOS. A diagnosis of SOS was based on 2 of the following 3 criteria: elevated bilirubin (>34 mmol/L or 2 mg/dL), increase in liver size or right upper quadrant liver pain, weight gain (>2.5% after GO infusion), along with exclusion of other liver diseases with this presentation. The study was conducted according to the Declaration of Helsinki and its amendments. Results: 512 patients were enrolled at 54 U.S. centers and 482 were analyzed. The study population consisted predominantly of men (59%); the mean age was 61.5 years; 73% had an ECOG performance status of 0 or 1 at baseline. 18% had received prior hematopoietic cell transplant (HCT), 4% had prior graft versus host disease (GVHD), 11% prior irradiation, 40% reported alcohol intake, and 19% were smokers. Most patients had received prior chemotherapy (87%). AML in first relapse was the indication for GO in 44%. Most patients received chemotherapy concomitantly with GO, most common were cytarabine (16%) and hydroxycarbamide (14%). The mean number of GO infusions per patient was 1.5 and the mean dose of GO per infusion was 7.8 mg/m2. The incidence of SOS was 8.9% (43/482; 95% confidence interval [CI]: 6.5% to 11.8%), with 19 cases classified as severe, 15 moderate, and 9 mild. Of 43 patients with SOS, 33 died within 6 months; of these, 20 died of AML progression. By multivariate analysis, only prior HCT was significantly related to development of moderate/severe SOS (odds ratio 2.2, CI 1.01–4.99). There was no evidence to suggest that age, blast count, body weight, GO dosing, prior chemotherapy, concomitant chemotherapy, or use of acetaminophen were related to development of SOS. 68% of patients died within 6 months. Progression of AML was the primary cause of death (73% of deaths); 7% were due to cardiovascular causes, 7% were due to infection, 6% were due to multiorgan failure, and 7% were due to other causes. SAEs occurred in 85% of patients; most (81%) due to other reasons, including AML, febrile neutropenia, pyrexia, and sepsis. Of the special interest categories, most SAEs were due to hepatic events (10%). 73% of patients experienced ESIs (both serious and nonserious); most ESIs were infusion-related events (46%) and 44% were hepatic events. Conclusions: GO can be safely administered in routine clinical practice with an overall 8.9% risk of SOS and with most cases moderate to severe. The only risk factor identified was prior HCT. Development of SOS following GO cannot be predicted in the majority of cases. Most ESIs were infusion-related events and most SAEs of the special interest categories were due to hepatic events.

B-cell chronic lymphocytic leukemia (B-CLL) is the most common type of leukemia in the adult population. It has a heterogeneous behavior and variable prognosis. While some patients experience indolent disease requiring no therapy for many years, others demonstrate a more aggressive type unresponsive to therapy. An accurate prognostic stratification is essential for optimizing the therapeutic strategy. Many prognostic factors are presently known, but their relationships and significance are often not clearly understood. Several markers have been identified, including IgVH mutation status and ZAP-70. Mutation of IgVH (less than 98% homology with the germline sequence) is correlated with better prognosis. Expression of ZAP-70, which is a cytoplasmic ζ-associated tyrosine-kinase essential for T-cell receptor signal transduction, is associated with more rapid disease progression and shorter survival. However, its detection by flow cytometry has many technical difficulties, resulting in high interlaboratory variability. The expression of intracellular ZAP-70 in 217 patients with diagnosis of B-CLL was determined using a new approach: quantitative flow cytometry on CD5+19+ tumor cells. Other laboratory and clinical parameters were evaluated, including gender, age, type and number of therapies, CD38 expression, cytogenetics and mutation status of IgVH. The expressions of ZAP-70 and CD38 were measured in molecules of equivalent soluble fluorochrome (MESF units). The results were correlated with mutation status of IgVH. Patients were divided into two groups by cluster analysis in a plot of IgVH homology versus ZAP-70 MESF (left panel). Overall survival curves for these groups are shown (right panel). It could follow that patients above the diagonal (triangles, group B) in the IgHV versus MESF plot have significantly poorer prognoses (p=0.0001) than do patients below this diagonal (circles, group A). Expression of CD38 above 15000 MESF showed worse prognosis for patients in the group B (p=0.035). Only three of 61 patients with chromosomal aberrations associated with poor prognosis (del11q and del17p) were found in the group A, but all of them had del13q present, as well. The authors introduced a new approach for evaluating ZAP-70 expression in B-CLL cells using quantitative flow cytometry that is easily standardized and not burdened with technical problems. Plotting IgVH homology (%) versus ZAP-70 quantitative expression (MESF) could clearly divide patients according to their prognoses. Figure Figure

SynopsisThe 60-item General Health Questionnaire (GHQ) and the Clinical Interview Schedule (CIS) were administered to a consecutive series of 194 patients with established or presumptive coronary heart disease (CHD) attending an out-patient cardiology unit. The GHQ proved to be a valid instrument for the routine screening of this population. The presence of organic anginal pain was associated with high scores on the GHQ, but with a lower specificity and a higher percentage of false positives. This was not found in patients with atypical or non-cardiac chest pain. These findings suggest a need for an upward revision of the cut-off score on the GHQ in patients with organic anginal pain. False negatives were found predominantly among patients with personality disorders, and in those characterized by the longstanding nature of their symptomatology and by higher levels of defensiveness.

International audience; This paper investigates the impact of reward shaping on a reinforcement learning-based spoken dialogue system's learning. A diffuse reward function gives a reward after each transition between two dialogue states. A sparse function only gives a reward at the end of the dialogue. Reward shaping consists of learning a diffuse function without modifying the optimal policy compared to a sparse one. Two reward shaping methods are applied to a corpus of dialogues evaluated with numerical performance scores. Learning with these functions is compared to the sparse case and it is shown, on simulated dialogues, that the policies learnt after reward shaping lead to higher performance.