Abstract
Kolmogorov complexity and Shannon entropy are conceptually different measures. However, for any recursive probability distribution, the expected value of Kolmogorov complexity equals its Shannon entropy, up to a constant. We study if a similar relationship holds for Renyi and Tsallis entropies of order alpha, showing that it only holds for alpha = 1. Regarding a time-bounded analogue relationship, we show that, for some distributions we have a similar result. We prove that, for universal time-bounded distribution m(t)(x), Tsallis and Renyi entropies converge if and only if alpha is greater than 1. We also establish the uniform continuity of these entropies.

Abstract
Rationale Complex clinical scenarios involving a high degree of uncertainty frequently lead to a poor agreement over diagnosis and management. However, inconsistent results can be found with the most widely used measures of agreement for continuous variables - the limits of agreement and the intraclass correlation coefficient. Aims and objectives We aim to improve the interpretation of agreement studies using continues variables. Methods and results Evaluation of agreement may be improved by complexity analysis and by categorization of variables, followed by the use of the proportions of agreement. Conclusions The average never characterizes a complex phenomenon and the methods used to access agreement in continuous variables are based on the mean. For future agreement studies, involving complex continuous variables, we recommend a complexity and categorical analysis.

Abstract
The use of an EPR within a hospital is essential in order to integrate and centralize patient healthcare information. With the introduction of this technology information security becomes an important issue, moreover when the EPR integrates several exam results and reports that need to be properly stored and managed. The Biostatistics and Medical Informatics Department in Porto's Faculty of Medicine is implementing a centralized Electronic Patient Record, the HSJ.ICU, to integrate several departments' information that comprises mainly electronic reports. The provision for the integrity of these documents is essential. Usually, the users of the system have blind trust in the information they access. The HSJ.ICU is implementing a process that digitally signs reports automatically, and therefore does not interfere with system's usability. It also provides for simple key management with the use of only one public key pair focusing protection in one single point. The digital signature provides real trust in the way it prevents and detects inconsistencies or errors that may affect information integrity. The approach presented in this paper will guarantee that when there is the need to access patient reports, whether now or in 20 years' time, those are still trustable and valid to be integrated within the EPR.

Abstract
Virtual electronic patient records (VEPR) enable the integration and sharing of healthcare information within large and heterogeneous organizations. The use of wireless technology can improve and fasten healthcare treatment because it brings information to the point of decision allowing also for users' mobility. This use has to comply with security requirements as the wireless technology introduces some specific security problems. The main objective of this work is to model and develop a proposal for a secure wireless architecture in order to access a VEPR. This VEPR is being used within a university hospital by more than 500 doctors, on a daily basis. Its users would greatly benefit if this service would be extended to a wider part of the hospital and not only to their workplace. They would achieve faster and greater mobility in the treatment of their patients. The wireless architecture includes the latest wireless security standards and protocols, and models security requirements according to users and organizations' needs. It provides an extra security layer to the wired system. In this paper we also present an evaluation of the proposed solutions against network attacks and its efficiency in terms of complexity and impact within the network. © 2007 IEEE.

Abstract
In the present paper, we answer a question raised in the paper Constructions and Bounds for Unconditionally Secure Non-Interactive Commitment Schemes, by Blundo et al, 2002, showing that there is a close relation between unconditionally secure commitment schemes and unconditionally secure authentication schemes, and that an unconditionally secure commitment scheme can be built from such an authentication scheme and an unconditionally secure cipher system. To investigate the opposite direction, we define optimal commitment systems and show that these must be resolvable design commitment schemes. Then, a proof is given that the resolvable design commitment schemes are a composition of an authentication system and a cipher system and the conclusion follows that this is the case for all optimal commitment systems. We also show how to build optimal schemes from transversal designs that are easy to build and can be more efficiently implemented than the proposal in the previously cited paper.

Abstract
Health information technologies are becoming more common in the health care practice and electronic health records are considered a keystone. However, there is also an increasing concern of keeping secure the patient's data and assure privacy. The aim of this paper was to perceive and illustrate by what means Portugal, the Netherlands and the United Kingdom intend to keep their electronic health information secure and assure patient privacy. Based in official documents collected in the health department's websites of the three selected countries, it was used an analysis model framework previously published that includes 14 topic areas of health records security policies. Analyzing 14 official documents of the subject countries, it was possible to design an illustrative table of the 14 topic areas regarding security and privacy issues. This table allows comparing the different security measures adopted by the three countries to keep the patient privacy, such as a network security and access control to system resources. Given the analysis of the official documents of the three countries, it was verified that none of them has a very thorough approach of how electronic health records should be implemented with regard to privacy and security. © 2011 ACM.