The paper presents revocation schemes in role-based access control models. We are particularly interested in two key issues: how to perform the revocation and how to manage the revocation policy. We show how to deal with these two aspects in our delegation model based on the OrBAC formalism and its administration licence concept. This model provides means to manage several types of of delegatio...

The purpose of this study was to identify predictors of conditional release failure amongst substance abusing women offenders. The sample consisted of federally sentenced women who were granted a conditional release between 1995 and 2000, and identified at intake as having a substance abuse problem. For the purposes of this study, conditional release included day parole, full parole, and statut...

Attribute-Based Encryption (ABE) is regarded as one of the most desirable cryptosystems realizing data security in the cloud storage systems. Functional Encryption (FE) which includes ABE and the ABE system with multiple authorities are studied actively today. However, ABE has the attribute revocation problem. In this paper, we propose a new revocation scheme using update information, i.e., rev...

The aim of this article is to establish whether there is anything intrinsically immoral about surrogacy arrangements from the perspective of the surrogate mother herself. Specific attention is paid to the claim that surrogacy is similar to prostitution in that it reduces women's reproductive labour to a form of alienated and/or dehumanized labour.

⎯In recent years, several random key predistribution schemes have been proposed to bootstrap keys for encryption, but the problem of key and node revocation has received relatively little attention. In this paper, based on a random key pre-distribution scheme using clustering, we present a novel random key revocation protocol, which is suitable for large scale networks greatly and removes compr...

Abstract Study question How do permanently infertile couples experience surrogacy in cross border reproductive care (CBRC) and which considerations they have relation to this? Summary answer The find treatment CBRC satisfying but feel forced use CBRC, estranged from own country, missing body, home What is known already Permanently Denmark must go abroad if want a genetically related child, as h...

At Eurocrypt 2011, Wee presented a generalization of threshold public key encryption, threshold signatures, and revocation schemes arising from threshold extractable hash proof systems. In particular, he gave instances of his generic revocation scheme from the DDH assumption (which led to the Naor-Pinkas revocation scheme), and from the factoring assumption (which led to a new revocation scheme...

Infertility affects 20% of couples in Nigeria. Assisted reproductive techniques (ART) offered in Nigeria include in-vitro fertilization (IVF), gamete donation and surrogacy. This cross-sectional questionnaire study aimed at assessing the acceptability of ART to women seeking infertility treatment at the University College Hospital, Ibadan, Nigeria. Of the 307 respondents, 58.3% were aware of IV...

Digital signatures provide authenticity and nonrepudiation. They are a standard cryptographic primitive with many applications in higher-level protocols. Groups featuring a computable bilinear map are particularly well suited for signature-related primitives. For some signature variants the only construction known uses bilinear maps. Where constructions based on, e.g., RSA are known, bilinear-m...