299 research outputs found

    Definition and Verification of Security Configurations of Cyber-Physical Systems

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    The proliferation of Cyber-Physical Systems (CPSs) is rais ing serious security challenges. These are complex systems, integrating physical elements into automated networked systems, often containing a variety of devices, such as sensors and actuators, and requiring complex management and data storage. This makes the construction of secure CPSs a challenge, requiring not only an adequate specification of secu rity requirements and needs related to the business domain but also an adaptation and concretion of these requirements to define a security configuration of the CPS where all its components are related. Derived from the complexity of the CPS, their configurations can be incorrect according to the requirements, and must be verified. In this paper, we propose a grammar for specifying business domain security requirements based on the CPS components. This will allow the definition of security requirements that, through a defined security feature model, will result in a configuration of services and security properties of the CPS, whose correctness can be verified. For this last stage, we have created a cata logue of feature models supported by a tool that allows the automatic verification of security configurations. To illustrate the results, the pro posal has been applied to automated verification of requirements in a hydroponic system scenario.Ministerio de Ciencia y Tecnología RTI2018-094283-B-C33 (ECLIPSE)Junta de Andalucía METAMORFOSIS (US-1381375)Junta de Castilla.La Mancha SBPLY-17-180501-000202 (GENESIS

    Many-Valued Institutions for Constraint Specification

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    We advance a general technique for enriching logical systems with soft constraints, making them suitable for specifying complex software systems where parts are put together not just based on how they meet certain functional requirements but also on how they optimise certain constraints. This added expressive power is required, for example, for capturing quality attributes that need to be optimised or, more generally, for formalising what are usually called service-level agreements. More specifically, we show how institutions endowed with a graded semantic consequence can accommodate soft-constraint satisfaction problems. We illustrate our approach by showing how, in the context of service discovery, one can quantify the compatibility of two specifications and thus formalise the selection of the most promising provider of a required resource.Peer Reviewe

    Prostate Cancer Susceptibility Loci Identified on Chromosome 12 in African Americans

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    Prostate cancer (PCa) is a complex disease that disproportionately affects African Americans and other individuals of African descent. A number of regions across the genome have been associated to PCa, most of them with moderate effects. A few studies have reported chromosomal changes on 12p and 12q that occur during the onset and development of PCa but to date no consistent association of the disease with chromosome 12 polymorphic variation has been identified. In order to unravel genetic risk factors that underlie PCa health disparities we investigated chromosome 12 using ancestry informative markers (AIMs), which allow us to distinguish genomic regions of European or West African origin, and tested them for association with PCa. Additional SNPs were genotyped in those areas where significant signals of association were detected. The strongest signal was discovered at the SNP rs12827748, located upstream of the PAWR gene, a tumor suppressor, which is amply expressed in the prostate. The most frequent allele in Europeans was the risk allele among African Americans. We also examined vitamin D related genes, VDR and CYP27B1, and found a significant association of PCa with the TaqI polymorphism (rs731236) in the former. Although our results warrant further investigation we have uncovered a genetic susceptibility factor for PCa in a likely candidate by means of an approach that takes advantage of the differential contribution of parental groups to an admixed population

    TRY plant trait database - enhanced coverage and open access

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    Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Estimating loss of Brucella abortus antibodies from age-specific serological data in elk

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    Serological data are one of the primary sources of information for disease monitoring in wildlife. However, the duration of the seropositive status of exposed individuals is almost always unknown for many free-ranging host species. Directly estimating rates of antibody loss typically requires difficult longitudinal sampling of individuals following seroconversion. Instead, we propose a Bayesian statistical approach linking age and serological data to a mechanistic epidemiological model to infer brucellosis infection, the probability of antibody loss, and recovery rates of elk (Cervus canadensis) in the Greater Yellowstone Ecosystem. We found that seroprevalence declined above the age of ten, with no evidence of disease-induced mortality. The probability of antibody loss was estimated to be 0.70 per year after a five-year period of seropositivity and the basic reproduction number for brucellosis to 2.13. Our results suggest that individuals are unlikely to become re-infected because models with this mechanism were unable to reproduce a significant decline in seroprevalence in older individuals. This study highlights the possible implications of antibody loss, which could bias our estimation of critical epidemiological parameters for wildlife disease management based on serological data

    Stem cell‐derived enteroid cultures as a tool for dissecting host‐parasite interactions in the small intestinal epithelium.

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    Toxoplasma gondii and Cryptosporidium spp. can cause devastating pathological effects in humans and livestock, and in particular to young or immunocompromised individuals. The current treatment plans for these enteric parasites are limited due to long drug courses, severe side effects, or simply a lack of efficacy. The study of the early interactions between the parasites and the site of infection in the small intestinal epithelium has been thwarted by the lack of accessible, physiologically relevant, and species-specific models. Increasingly, 3D stem cell-derived enteroid models are being refined and developed into sophisticated models of infectious disease. In this review we shall illustrate the use of enteroids to spearhead research into enteric parasitic infections, bridging the gap between cell line cultures and in vivo experiments

    Effect of Population, Collection Year, After-Ripening and Incubation Condition on Seed Germination of \u3cem\u3eStipa bungeana\u3c/em\u3e

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    Knowledge of the germination behavior of different populations of a species can be useful in the selection of appropriate seed sources for restoration. The aim of this study was to test the effect of seed population, collection year, after-ripening and incubation conditions on seed dormancy and germination of Stipa bungeana, a perennial grass used for revegetation of degraded grasslands on the Loess Plateau, China. Fresh S. bungeana seeds were collected from eight locally-adapted populations in 2015 and 2016. Dormancy and germination characteristics of fresh and 6-month-old dry-stored seeds were determined by incubating them over a range of alternating temperature regimes in light. Effect of water stress on germination was tested for fresh and 6-month-old dry-stored seeds. Seed dormancy and germination of S. bungeana differed with population and collection year. Six months of dry storage broke seed dormancy, broadened the temperature range for germination and increased among-population differences in germination percentage. The rank order of germination was not consistent in all germination tests, and it varied among populations. Thus, studies on comparing seed dormancy and germination among populations must consider year of collection, seed dormancy states and germination test conditions when selecting seeds for grassland restoration and management

    Hispanic Latin America, Spain and the Spanish-speaking Caribbean: A rich source of reference material for public health, epidemiology and tropical medicine

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    There is a multiplicity of journals originating in Spain and the Spanish-speaking countries of Latin America and the Caribbean (SSLAC) in the health sciences of relevance to the fields of epidemiology and public health. While the subject matter of epidemiology in Spain shares many features with its neighbours in Western Europe, many aspects of epidemiology in Latin America are particular to that region. There are also distinctive theoretical and philosophical approaches to the study of epidemiology and public health arising from traditions such as the Latin American social medicine movement, of which there may be limited awareness. A number of online bibliographic databases are available which focus primarily on health sciences literature arising in Spain and Latin America, the most prominent being Literatura Latinoamericana en Ciencias de la Salud (LILACS) and LATINDEX. Some such as LILACS also extensively index grey literature. As well as in Spanish, interfaces are provided in English and Portuguese. Abstracts of articles may also be provided in English with an increasing number of journals beginning to publish entire articles written in English. Free full text articles are becoming accessible, one of the most comprehensive sources being the Scientific Electronic Library Online (SciELO). There is thus an extensive range of literature originating in Spain and SSLAC freely identifiable and often accessible online, and with the potential to provide useful inputs to the study of epidemiology and public health provided that any reluctance to explore these resources can be overcome. In this article we provide an introduction to such resources
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