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New mobile communication technologies are expected to be broadly available in the near future. Those technologies (multimedia-enabled devices and broadband access to the Internet) will enable new services involving video transmission. Service providers are likely to want the customer to pay for contents, whereas they will also want their intellectual property protected. We present a system that integrates content, fine-grain pay-per-view and copyright protection with a rich variety of multimedia output devices and transmission networks.

After abnormal head-up tilt test (HUT), several trials have evaluated treatment strategies for vasovagal syncope (VVS). However, few unequivocal results have been obtained. The aim of the study was to prospectively analyze the natural history of patients with VVS who did not undergo specific treatment but received education for avoiding syncope after an abnormal HUT.From 1996, 334 consecutive patients with VVS and an abnormal HUT result were followed. All of them received education for avoiding syncope as first-line therapy.During 30.4 +/- 21 months, there were no cardiac deaths. However, 101 patients (30.2%) had recurrences (1 recurrence, n = 64;or =2, n = 37), which were not influenced by the type of response during HUT or by age. Time to first recurrence was correlated with the number of recurrences (r: -0.34, P =.0001). Mean recurrence-free time was 50.1 months (95% CI 46-54) and the cumulative probability of no recurrence was 69.8%. Receiver operator character curve analysis, demonstrated significant differences in the recurrence rate between patients with5 oror =5 previous episodes of syncope (25.1% vs 44%; P =.001). In addition, the mean recurrence-free time of patients with5 episodes was significantly longer (54.1 months) than in patients withor =5 episodes (39.6 months; P =.0005). Multivariate logistic regression identified the previous number of episodes as an independent risk marker of recurrences (odds ratio 2.34, 95% CI 1.4-3.8, P =.001). Age (at HUT performance) as a continuous variable was not a predictor of outcome.Survival of patients with VVS presenting after an abnormal HUT is excellent. Although the broad majority of those patients do not suffer recurrences after education, the number of previous syncopal episodes critically influences the recurrence rate.

As new mobile communication technologies are becoming broadly available, there is urgent pressure to populate them with services that provide returns for the huge investments made by telecommunications operators. Services around video transmission are expected to play a key role: news broadcasting, videoconferencing, movie channels, on-line gambling, etc. The goal of the STREAMOBILE project is to demonstrate an Internet pay-per-view distribution system toward GPRS and UMTS mobile devices. Copyright-protected contents are streamed to the customer and a micropayment scheme is used so that contents are not paid for in advance, but as they are being received by the customer. This paper presents an evolving prototype., whose client software has been designed in such a way that it can be easily migrated to 3G mobile devices.

Fingerprinting schemes allow tracing of illegally redistributed multimedia contents. When using asymmetric fingerprinting, the merchant does not know the marked copy nor the embedded mark, so fraudulent distribution of the content by the merchant - which could lead to framing honest customers - is not possible. A problem with the deployment of classical asymmetric fingerprinting protocols is that they are based on information transfer methods whose implementation is difficult, if not infeasible. We propose an architecture to obtain asymmetric fingerprinting through symmetric (and thus implementable) schemes and a trusted third party (TTP).

Multicast content delivery can be expected to become a major source of revenue with the increase of private broadband fixed and mobile communications. Several multicast applications require the receivers to securely send some real-time information back to the source, which leads to a many-to-one communication scenario. Using unicast connections to send this reverse traffic results in a data implosion which may swamp the source with incoming communication. In order to avoid this problem, a method for aggregating the information as it is being sent back to the source is presented in this paper. Confidentiality and authentication are guaranteed at the symbol level for this reverse realtime traffic.

When designing a secure Internet version for keno or bingo for a large group of players, a multicast communication model is likely to be used for source-to-players communication. For a large group of players, this can potentially overwhelm the source, a problem which is known as implosion. We present a scheme for large-scale bingo which avoids implosion in the many-to-one communication between the players and the hall. The resulting scheme aggregates information using a probabilistic public-key additive privacy homomorphism and guarantees the security of communications.

The knowledge of computer applications such as word processing or Internet-based communication is essential in most jobs. On the other hand, most professional training programs for unemployed people contain a computer course for those who have never used a computer. Middle-aged adults present several difficulties in order to learn core computer skills, which must be overcome in order for these people to be able to handle basic computer applications successfully. In this paper, we present a 50 hour program to teach computer skills for middle-aged adults.

Immunophenotype is an essential parameter in the diagnosis of hematological malignancies. Flow cytometry (FCM) is used in the analysis of bone marrow or peripheral blood samples but is less frequently used in the evaluation of tissue biopsies with suspected hematological malignancies. The aim of this study was to analyze the role of FCM in the diagnosis of biopsies from patients with a suspected hematological disorder.A total of 422 consecutive biopsies were studied using standard morphology, immunohistochemistry (IHC), and FCM. Results of FCM were obtained in less than 3 h and were interpreted independently from morphology and IHC.A strong correlation between malignant disease and abnormal pattern of FCM was observed (218 of 250) with the exception of Hodgkin disease (P0.001). Overall, negative predictive value was 0.52 and positive predictive value was 1. Light chain restriction was observed in 182 of 201 B-cell lymphoma and in 0 of 142 non-B-cell disorders by FCM. In contrast, light chain pattern could only be evaluated in 38 of 91 cases by IHC. FCM allowed a rapid diagnosis of infrequent or high-grade malignancies such as histiocytic sarcoma or T-lymphoblastic lymphoma. The addition of FCM in the routine study of tissue biopsies facilitates the diagnosis of double pathology in five (1%) patients.FCM is a fast and reliable methodology for phenotyping tissue samples, which easily detects infrequent hematological malignancies, disease-specific phenotypes and clonality in B-cell lymphomas. Moreover, the simultaneous recognition of different cell populations allows the diagnosis of composite cell lymphomas, or double pathologies.

Objectives The purpose of this study was to prospectively analyze the performance and safety of a new programmable, fully automatic external cardioverter-defibrillator (AECD) in a European multicenter trial. Background Although, the response time to cardiac arrest (CA) is a major determinant of mortality and morbidity, in-hospital strategies have not significantly changed during the last 30 years. Methods Patients (n = 117) at risk of CA in monitored wards (n = 51) and patients undergoing electrophysiologic testing or implantable cardioverter-defibrillator (ICD) implantation (n = 66) were enrolled. The accuracy of the automatic response of the device to any change of rhythm (lasting >1 s and >4 beats) was confirmed by reviewing the simultaneously recorded Holter data and the programmed parameters. Results During 1,240 h, 1,988 episodes of rhythm changes were documented. A total of 115 episodes lasted ≥10 s or needed treatment (pacing, n = 32; ICD, n = 51; AECD, n = 35) for termination. The device detected ventricular tachyarrhythmias with a sensitivity of 100% and specificity of 97.6% (true negatives, n = 1,454; true positives, n = 499; false positives, n = 35; false negatives, n = 0). The false positives were all caused by T-wave oversensing during ventricular pacing. There were no complications or adverse events. The mean response time was 14.4 s for those episodes needing a full charge of the capacitor. Conclusions This new AECD is safe and effective in detecting, monitoring, and treating spontaneous arrhythmias. This fully automatic device shortens the response time to treatment, and it is likely that it will significantly improve the outcome of patients with in-hospital CA.

Successive failure of copy prevention systems has caused copy detection to become the most promising option to protect the intellectual property of multimedia content. Fingerprinting techniques rely on invisible watermarks embedded in the copy sold in order to identify the buyer. We address the problem of security against collusion attacks in proposals for fingerprinting in a multicast environment. A proposal that combines Boneh-Shaw collusion-secure codes and encryption-based fingerprinting is presented that results in a collusion-secure fingerprinting system for multicast communications.

Background Chest pain is a frequent symptom in the emergency department and often presents a diagnostic challenge. Because coronary thrombosis is a hallmark of acute ischemic syndromes, the substrates of the coagulation and fibrinolysis cascades may be markers of coronary ischemia. The objective of this study was to determine the diagnostic value of several hemostatic markers in patients presenting to the emergency department (ED) with chest pain syndromes. Methods Two hundred fifty-seven consecutive patients with acute chest pain were studied in this prospective study conducted in an urban ED. D- Dimer levels were measured at admission to the ED in all patients. We also measured thrombin-antithrombin complexes, prothrombin fragment 1+2, activated factor VII, and fibrinogen. We used regression analysis to estimate the likelihood of myocardial infarction and the diagnostic value of D -dimer. Results D -Dimer and fibrinogen levels were significantly higher in patients with acute ischemic events (myocardial infarction and unstable angina) than in nonischemic patients ( P P =.02, respectively). The other hemostatic markers were not significantly elevated in patients with ischemic events. D -Dimer level >500 μg/L had an independent diagnostic value for myocardial infarction and increased the diagnostic sensitivity of the electrocardiogram and history from 73% to 92%. Conclusion D -Dimer, an expression of ongoing thrombus formation and lysis, is a marker of substantial incremental value for the early diagnosis of acute coronary syndromes presenting with chest pain. It adds independent information to the traditional assessment for myocardial infarction. D -Dimer can be incorporated into clinical decision models in the ED. (Am Heart J 2000;140:379-84.)

Animal studies1–3 have shown that increased basic dispersion of repolarisation lowers the ventricular fibrillation threshold and facilitates induction of reentrant ventricular arrhythmias.

In patients surviving acute MI, identification of those at high risk for life-threatening ventricular tachyarrhythmias and/or sudden death is of great importance. Numerous strategies based on indices such as the degree of left ventricular dysfunction, complex ventricular arrhythmias, or parameters of autonomic dysfunction have not yet led to an effective identification of the individual patient at risk. During the past decade, many investigators have recorded low amplitude, high frequency components in the terminal QRS complex (so-called late potentials) from patients prone to sustained ventricular tachycardia. The SAECG has been used to predict life-threatening tachyarrhythmias in patients after acute MI and to screen for inducible ventricular tachycardia in patients with unexplained syncope or sustained ventricular tachycardia. This review article describes the most frequently applied methodology and clinical applications of the SAECG in post-MI patients and discusses the usefulness of noninvasive recordings in various other clinical settings.

Background Programmed ventricular stimulation is commonly used to guide therapy in post–myocardial infarction patients with sustained monomorphic ventricular tachycardia (VT) or ventricular fibrillation (VF). In patients with valvular heart disease presenting with spontaneous VT, VF, or syncope, the usefulness of this technique is still unclear. The aim of the study was to analyze whether programmed ventricular stimulation was helpful in guiding therapy and determining prognosis in 97 patients with valvular heart disease presenting with VT (60%), VF (18%), or syncope (22%). Methods and Results Patients were classified as having either predominant ventricular pressure or volume overload or no significant pressure or volume overload. Overall, sustained VT or VF was inducible in 38 (39%) and 19 (20%) patients, respectively. Forty-six (47%) patients were discharged on antiarrhythmic drugs, 29 (30%) received an implantable cardioverter-defibrillator, and 22 (23%) remained without therapy. With serial drug testing, inducibility was completely or partially suppressed in 18 (19%) and 9 (9%) patients, respectively. During a mean follow-up of 51 months (n=97), 17 patients (18%) died (sudden death, n=7; heart failure, n=4; noncardiac causes, n=6). One-, 2- and 3-year event-free survival for sudden death, sustained VT, or VF was 77%, 68%, and 61%, respectively. Only inducibility of VT during baseline study ( P P Conclusions Although programmed ventricular stimulation seems to predict adverse outcome, serial drug testing is unreliable in guiding therapy. The type of workload imposed on the ventricles influences outcome, being worse in patients with left ventricular volume overload. Therefore, implantation of a cardioverter-defibrillator should be considered early for the management of these patients.

The aim of this study was to analyze the ability of the multiresolution decomposition of the signal-averaged electrocardiogram (ECG) to discriminate between patients who develop life-threatening ventricular arrhythmias after myocardial infarction and those who do not and to compare the predictive values of this approach with those obtained from the analysis of ventricular late potentials in the time domain. Signal-averaged ECGs of 769 prospectively included patients were analyzed. A total of 42 arrhythmic events occurred during the follow-up period. For numerical calculations of wavelet analysis, the total and relative energies of the QRS complex were obtained in seven frequency bands. The combination of the relative energy in the frequency bands 7.8–15.6 Hz and 62.5–125 Hz enhanced statistical performance as compared with the time-domain parameters (positive predictive accuracy, 11.3 vs 8.2%). Combining wavelet transform and time-domain parameters enhanced the predictive values even more (positive predictive accuracy, 14.3%) compared with applying each method alone.

The prognostic significance of heart rate variability derived from 24-hour electrocardiographic recordings was investigated in 250 patients with acute myocardial infarction. During a follow-up of 6 months 15 patients experienced a serious arrhythmic event. These patients showed a significantly reduced beat to beat variability (p = 0.006), a slightly reduced 5-min variability (p = 0.04) and no significant differences in the 24-hour variability compared to the patients free of arrhythmic events. Based on Cox proportional hazard analysis, beat to beat variability remained an independent risk factor (p = 0.0036) in addition to the presence or absence of ventricular late potentials (p = 0.0004) and history of previous infarction (p = 0.04).

A 73-year-old woman with dilated cardiomyopathy presented with heart failure. The ECG showed sinus rhythm with left bundle branch block, left-axis deviation and prolonged QRS duration and frequent ventricular premature complexes from the left ventricular septal wall were present. Ventricular premature beats had narrower QRS duration than sinus node beats conducted through the His-purkinje fibers consistent with resynchronizing beats. The mechanisms of narrowing of the QRS complex produced by premature beats in cases of impaired intra and interventricular conduction are discussed.

The incidence of coronary artery disease (CAD) is greater in men than in women. The aim of the study was to analyze whether any gender-related differences in patients with CAD and documented spontaneous sustained ventricular tachyarrhythmias exist, and which parameters influence the induction of sustained ventricular tachyarrhythmias. The data of 250 patients [43 women (17.2%) and 207 men (82.8%)] with spontaneous sustained ventricular tachycardia [n = 190 (76%)] and fibrillation [n = 60 (24%)] who underwent coronary and left ventricular angiography, electrophysiological study, and signal-averaging electrocardiogram (ECG) form the basis of this analysis. No gender-related differences could be observed in age, number of diseased coronary arteries, history, location and number of myocardial infarctions, presence of left ventricular aneurysm, ejection fraction, type of spontaneous or induced arrhythmias, right ventricular effective refractory period, and signal-averaged ECG parameters. Age, presence of previous myocardial infarction, and ejection fraction were significant predictors (p < 0.001) of inducibility of sustained ventricular tachyarrhythmias. Once CAD has begun, female and male patients present similar clinical and electrophysiologic characteristics. Thus, both genders should benefit similarly from diagnostic and therapeutic approaches if they are referred to the hospital or to invasive interventions at similar intervals in the course of their illness.

It was analyzed whether the response to sotalol can predict the response to amiodarone as evaluated by programmed ventricular stimulation in 30 patients with coronary artery disease and documented recurrent sustained ventricular tachycardia (VT). Programmed ventricular stimulation was performed using 1 or 2 extrastimuli during sinus rhythm and 4 drive cycle lengths at 2 right ventricular sites. If no ventricular tachyarrhythmia was induced, a third extrastimulus was introduced during a paced cycle length of 500 ms. During the control study, VT (mean cycle length 305 +/- 63 ms) was induced in all patients, and the right ventricular effective refractory period (during S1-S1 = 500 ms) was 223 +/- 12 ms. After sotalol, sustained and nonsustained VT were inducible in 22 (73%) and 7 (23%) patients, respectively. One patient did not undergo stimulation on sotalol, because of side effects. After amiodarone, sustained and nonsustained VT were inducible in 23 (77%) and 7 (23%) patients, respectively. The mean cycle length of the induced VT was prolonged after both drugs by 17% (p0.001). The effective refractory period was prolonged by 15% (p0.001) after sotalol and by 13% (p0.001 compared with baseline study; p = NS between both drugs) after amiodarone. Thus, concordant results (effective or ineffective drug) between sotalol and amiodarone were found in 26 patients (87%).(1) The effects of sotalol and amiodarone on the cycle length of induced VT and on right ventricular effective refractory period were similar; and (2) inability to suppress VT by amiodarone can be predicted from the response to sotalol.(ABSTRACT TRUNCATED AT 250 WORDS)

To the Editors:Typhoid fever is a systemic infection caused by Salmonellaenterica serotype Typhi (S. Typhi). In 2006, the incidence in Spain was 82 cases, of which 17 were in Catalonia (0.21 cases per 100,000 inhabitants).Prognosis depends on the speed of diagnosis and treatment. Factors such as age

The underlying arrhythmia in most patients who die suddenly outside the hospital is some type of ventricular tachyarrhythmia, mostly monomorphic ventricular tachycardia degenerating into ventricular fibrillation. This has been shown in a multitude of long-ECG recordings in patients who died suddenly [1, 2]. In only a minority of patients, sudden cardiac death is due to bradyarrhythmias. Bayes de Luna et al. reported on 61 patients from the literature who died from ventricular fibrillation during ambulatory long-term ECG recording [1]. Though ventricular fibrillation was the initial rhythm in 28% of cases, the initial rhythm was a monomorphic ventricular tachycardia subsequently degenerating into ventricular fibrillation in 69% of cases. In the remaining 3% of cases, ventricular flutter degenerated into ventricular fibrillation. These initiating ventricular tachycardias frequently had a rate below 300 bpm [2].

For almost ten years, signal averaging has been used for noninvasive recording of ventricular late potentials [1–10]. Delayed and fractionated potentials have been observed in regions of experimental myocardial infarction [11–13], as well as during intraoperative epicardial and endocardial mapping [1, 2, 14, 15] and endocardial catheter mapping in patients with ventricular tachycardia [16, 17].

Densities of ethanol + water + potassium nitrate and ethanol + water + sodium nitrate mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of the salt and ethanol, at 298.15 K. From these densities, apparent molar volumes of both electrolytes in ethanol + water mixtures have been calculated, and partial molar volumes at infinite dilution have been evaluated.

The amount of computer-stored information is growing faster with each passing day. This growth and the way in which the stored data are accessed through a variety of channels have raised the alarm about the protection of the individual privacy of the respondents whose data are being collected and stored. On the one hand, data should be available to researchers and statistical agencies so that the necessary research and planning activities can be conducted. However, on the other hand, the right of respondents to privacy must be protected. Statistical disclosure control (SDC) is the discipline which cares about keeping a balance between data access and privacy protection. k-Anonymity is one particular approach to SDC for individual data (microdata): the record corresponding to a specific respondent is k-anonymous if an intruder can at best link the record to a group of k respondents containing the correct one. This paper surveys the use of a special clustering technique called microaggregation to provide k-anonymity.

The extractive distillation in which an electrolyte is employed as the extractive agent is an important alternative to the conventional methods for separating mixtures involving azeotropes. Isobaric vapor-liquid equilibrium for ethanol (1) + water(2) + copper(II) chloride (3) at different mole fractions of copper(II) chloride has been measured at 100.0 kPa. The results in the range where the mole fraction of salt in the liquid phase was less than 0.146 times the mole fraction of water were correlated by assuming that the salt was in ionic form and it was associated only with the water. Thermodynamic consistency was checked according to Herington`s method with satisfactory results.

There is a number of applications requiring a community of many senders to transmit some real-time information to a single receiver. Using unicast connections to send this traffic can result in data implosion and swamp the receiver. In [Domi04], a mechanism was proposed for secure bit transmission in large-scale many-to-one communications; we propose here an extension for securely sending q-ary symbols.

Densities of ethanol + water + cobalt(II) chloride mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of salt, at 298.15 K. From these densities, apparent molar volumes of the electrolyte in these mixtures have been calculated, and partial molar volumes at infinite dilution have been evaluated, at different concentrations of alcohol in the solvent.

Densities of ethanol + water + strontium bromide mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of salt, at 298.15 K. From these densities, apparent molar volumes of the electrolyte in these mixtures have been calculated and partial molar volumes at infinite dilution have been evaluated, at different concentrations of alcohol in the solvent

Densities of ethanol + water + strontium chloride mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of the salt and ethanol, at 298.15 K. From these densities, apparent molar volumes of the electrolyte in these mixtures have been calculated, and partial molar volumes at infinite dilution have been evaluated.

Densities of ethanol + water + strontium nitrate and ethanol + water + copper(II) chloride mixtures have been measured with an oscillating-tube densimeter over a large range of concentrations of the salt and ethanol, at 298.15 K. From these densities, apparent molar volumes of both electrolytes in ethanol + water mixtures have been calculated, and partial molar volumes at infinite dilution have been evaluated.

Population pyramids have rapidly changed their shape worldwide. Specially in industrialised countries, where a steady ageing process is taking place. Due to the ageing of the population, age-related illnesses such as mild cognitive impairment (MCI) and dementia are becoming commonplace and healthcare systems struggle to improve the quality of life of patients and carers. Wandering and disorientation are common symptoms amongst patients with MCI, and they could lead to fatal outcomes. In this article we propose a wandering detection technique based on the analysis of randomness in patients’ trajectories, which are gathered by means of standard low-cost mobile phones with GPS.

The emerging paradigm of the cognitive city, which augments smart cities with learning and behavioral change capabilities, is gaining increasing attention as a promising solution to the challenges of future mega-cities. Cognitive cities are built upon artificial learning and behavioral analysis techniques founded on the exploitation of human-machine collective intelligence. Hence, cognitive cities rely on the sharing of citizens’ daily-life data, which might be considered sensitive personal data. In this context, privacy and security of the shared information become critical issues that have to be addressed to guarantee the proper deployment of cognitive cities and the fundamental rights of people. This article provides a thorough literature review using the recommendations for systematic reviews proposed by Vom Brocke et al. and the PRISMA statement. We analyze peer-reviewed publications indexed in ACM Digital Library, IEEE Xplore, Scopus, and Web of Science until July 2020. We identify the main challenges on privacy and information security within cognitive cities, and the proposals described in the literature to address them. We conclude that many challenges remain open and we suggest several research lines that will require further examination in the years to come.