549 research outputs found
A Framework for Evaluating Security in the Presence of Signal Injection Attacks
Sensors are embedded in security-critical applications from medical devices
to nuclear power plants, but their outputs can be spoofed through
electromagnetic and other types of signals transmitted by attackers at a
distance. To address the lack of a unifying framework for evaluating the
effects of such transmissions, we introduce a system and threat model for
signal injection attacks. We further define the concepts of existential,
selective, and universal security, which address attacker goals from mere
disruptions of the sensor readings to precise waveform injections. Moreover, we
introduce an algorithm which allows circuit designers to concretely calculate
the security level of real systems. Finally, we apply our definitions and
algorithm in practice using measurements of injections against a smartphone
microphone, and analyze the demodulation characteristics of commercial
Analog-to-Digital Converters (ADCs). Overall, our work highlights the
importance of evaluating the susceptibility of systems against signal injection
attacks, and introduces both the terminology and the methodology to do so.Comment: This article is the extended technical report version of the paper
presented at ESORICS 2019, 24th European Symposium on Research in Computer
Security (ESORICS), Luxembourg, Luxembourg, September 201
The reassessment of the Roman military presence in Galicia and northern Portugal through digital tools: Archaeological diversity and historical problems
This is the final version. Available on open access from the University of the Aegean via the DOI in this recordTraditionally, the study of the Roman military presence in Galicia (Spain) and Northern Portugal has been based on the fragmentary documentation offered by Greek and Latin authors or epigraphy, with archaeology occupying a very secondary place in these historical narratives. In particular, the information is very scarce for the period between the 2nd century BCE and 1st century CE, when these territories were conquered and integrated into the Roman world. This work presents new Roman military sites discovered through an integrated methodology involving an intensive application of remote sensing techniques in order to provide information to foster a paradigm shift in this field of study. Distributed over a wide geographical area and displaying a wide morpho-typological and locational diversity, this new archaeological evidence not only reflects the ability of the Roman army to adapt to local natural and cultural environments, but also reveals a major operational and logistical assortment that may relate to the diachronic nature of the military presence in the region.Regional Government of GaliciaGalician Innovation Agency (GAIN)European Union Horizon 202
O Penedo dos Lobos: Roman military activity in the uplands of the Galician Massif (Northwest Iberia)
This is the final version. Available from Routledge via the DOI in this record. A new Roman military site was recently detected in Galicia, Spain, an area where the army presence had been challenging to trace until date. O Penedo dos Lobos is a playing-card shaped camp with very distinctive, fortified entrances. The archaeological survey conducted on this site in the summer of 2018 allowed us to recover some elements of Roman militaria, as well as numismatic evidence dating back to late 1st c. BC, thus suggesting a connection with the Cantabrian-Asturian Wars of Augustan times. However, there is still some uncertainty regarding the specific task undertaken by the military contingent that occupied this site. Besides its historical implications, a focus will be given to the methodology applied for the archaeological survey of this site. This has shed new light on the Roman military presence in Galicia, allowing its integration into wider European debates on Roman conquest and expansion.European CommissionXunta de GaliciaXunta de Galici
Comprehensive analyses of DNA repair pathways, smoking and bladder cancer risk in Los Angeles and Shanghai
Tobacco smoking is a bladder cancer risk factor and a source of carcinogens that induce DNA damage to urothelial cells. Using data and samples from 988 cases and 1,004 controls enrolled in the Los Angeles County Bladder Cancer Study and the Shanghai Bladder Cancer Study, we investigated associations between bladder cancer risk and 632 tagSNPs that comprehensively capture genetic variation in 28 DNA repair genes from four DNA repair pathways: base excision repair (BER), nucleotide excision repair (NER), non-homologous end-joining (NHEJ) and homologous recombination repair (HHR). Odds ratios (ORs) and 95% confidence intervals (CIs) for each tagSNP were corrected for multiple testing for all SNPs within each gene using pACT and for genes within each pathway and across pathways with Bonferroni. Gene and pathway summary estimates were obtained using ARTP. We observed an association between bladder cancer and POLB rs7832529 (BER) (pACT = 0.003; ppathway = 0.021) among all, and SNPs in XPC (NER) and OGG1 (BER) among Chinese men and women, respectively. The NER pathway showed an overall association with risk among Chinese males (ARTP NER p = 0.034). The XRCC6 SNP rs2284082 (NHEJ), also in LD with SREBF2, showed an interaction with smoking (smoking status interaction pgene = 0.001, ppathway = 0.008, poverall = 0.034). Our findings support a role in bladder carcinogenesis for regions that map close to or within BER (POLB, OGG1) and NER genes (XPC). A SNP that tags both the XRCC6 and SREBF2 genes strongly modifies the association between bladder cancer risk and smoking
Differential phenotypic expression of a novel PDHA1 mutation in a female monozygotic twin pair
Pyruvate dehydrogenase complex (PDC) deficiency caused by mutations in the X-linked PDHA1 gene has a broad clinical presentation, and the pattern of X-chromosome inactivation has been proposed as a major factor contributing to its variable expressivity in heterozygous females. Here, we report the first set of monozygotic twin females with PDC deficiency, caused by a novel, de novo heterozygous missense mutation in exon 11 of PDHA1 (NM_000284.3: c.1100A>T). Both twins presented in infancy with a similar clinical phenotype including developmental delay, episodes of hypotonia or encephalopathy, epilepsy, and slowly progressive motor impairment due to pyramidal, extrapyramidal, and cerebellar involvement. However, they exhibited clear differences in disease severity that correlated well with residual PDC activities (approximately 60% and 20% of mean control values, respectively) and levels of immunoreactive E1α subunit in cultured skin fibroblasts. To address whether the observed clinical and biochemical differences could be explained by the pattern of X-chromosome inactivation, we undertook an androgen receptor assay in peripheral blood. In the less severely affected twin, a significant bias in the relative activity of the two X chromosomes with a ratio of approximately 75:25 was detected, while the ratio was close to 50:50 in the other twin. Although it may be difficult to extrapolate these results to other tissues, our observation provides further support to the hypothesis that the pattern of X-chromosome inactivation may influence the phenotypic expression of the same mutation in heterozygous females and broadens the clinical and genetic spectrum of PDC deficiency
Differential phenotypic expression of a novel PDHA1 mutation in a female monozygotic twin pair.
Pyruvate dehydrogenase complex (PDC) deficiency caused by mutations in the X-linked PDHA1 gene has a broad clinical presentation, and the pattern of X-chromosome inactivation has been proposed as a major factor contributing to its variable expressivity in heterozygous females. Here, we report the first set of monozygotic twin females with PDC deficiency, caused by a novel, de novo heterozygous missense mutation in exon 11 of PDHA1 (NM_000284.3: c.1100A>T). Both twins presented in infancy with a similar clinical phenotype including developmental delay, episodes of hypotonia or encephalopathy, epilepsy, and slowly progressive motor impairment due to pyramidal, extrapyramidal, and cerebellar involvement. However, they exhibited clear differences in disease severity that correlated well with residual PDC activities (approximately 60% and 20% of mean control values, respectively) and levels of immunoreactive E1α subunit in cultured skin fibroblasts. To address whether the observed clinical and biochemical differences could be explained by the pattern of X-chromosome inactivation, we undertook an androgen receptor assay in peripheral blood. In the less severely affected twin, a significant bias in the relative activity of the two X chromosomes with a ratio of approximately 75:25 was detected, while the ratio was close to 50:50 in the other twin. Although it may be difficult to extrapolate these results to other tissues, our observation provides further support to the hypothesis that the pattern of X-chromosome inactivation may influence the phenotypic expression of the same mutation in heterozygous females and broadens the clinical and genetic spectrum of PDC deficiency
Urinary tract infections and reduced risk of bladder cancer in Los Angeles
We investigated the association between urinary tract infections (UTIs) and transitional cell carcinoma of the bladder in a population-based case–control study in Los Angeles covering 1586 cases and age-, gender-, and race-matched neighbourhood controls. A history of bladder infection was associated with a reduced risk of bladder cancer among women (odds ratio (OR), 0.66; 95% confidence interval (CI), 0.46–0.96). No effect was found in men, perhaps due to power limitations. A greater reduction in bladder cancer risk was observed among women with multiple infections (OR, 0.37; 95% CI, 0.18–0.78). Exclusion of subjects with a history of diabetes, kidney or bladder stones did not change the inverse association. A history of kidney infections was not associated with bladder cancer risk, but there was a weak association between a history of other UTIs and slightly increased risk among men. Our results suggest that a history of bladder infection is associated with a reduced risk of bladder cancer among women. Cytotoxicity from antibiotics commonly used to treat bladder infections is proposed as one possible explanation
Different rates of spontaneous mutation of chloroplastic and nuclear viroids as determined by high-fidelity ultra-deep sequencing
[EN] Mutation rates vary by orders of magnitude across biological systems, being higher for simpler genomes. The simplest known genomes correspond to viroids, subviral plant replicons constituted by circular non-coding RNAs of few hundred bases. Previous work has revealed an extremely high mutation rate for chrysanthemum chlorotic mottle viroid, a chloroplastreplicating viroid. However, whether this is a general feature of viroids remains unclear. Here, we have used high-fidelity ultra-deep sequencing to determine the mutation rate in a common host (eggplant) of two viroids, each representative of one family: the chloroplastic eggplant latent viroid (ELVd, Avsunviroidae) and the nuclear potato spindle tuber viroid (PSTVd, Pospiviroidae). This revealed higher mutation frequencies in ELVd than in PSTVd, as well as marked differences in the types of mutations produced. Rates of spontaneous mutation, quantified in vivo using the lethal mutation method, ranged from 1/1000 to 1/800 for ELVd and from 1/7000 to 1/3800 for PSTVd depending on sequencing run. These results suggest that extremely high mutability is a common feature of chloroplastic viroids, whereas the mutation rates of PSTVd and potentially other nuclear viroids appear significantly lower and closer to those of some RNA viruses.This work was supported by the European Research Council (erc.europa.eu; ERC-2011-StG-281191-VIRMUT to RS), the Spanish Ministerio de Economia y Competitividad (www.mineco.gob.es; BFU2013-41329 grant to RS, BFU2014-56812-P grant to RF, and a predoctoral fellowship to ALC), and the Spanish Junta de Comunidades de Castilla-La Mancha (www.castillalamancha.es;postdoctoral fellowship to CB). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.López-Carrasco, MA.; Ballesteros Martínez, C.; Sentandreu, V.; Delgado Villar, SG.; Gago Zachert, SP.; Flores Pedauye, R.; Sanjuan Verdeguer, R. (2017). Different rates of spontaneous mutation of chloroplastic and nuclear viroids as determined by high-fidelity ultra-deep sequencing. PLoS Pathogens. 13(9):1-17. https://doi.org/10.1371/journal.ppat.1006547S117139Ganai, R. A., & Johansson, E. (2016). DNA Replication—A Matter of Fidelity. Molecular Cell, 62(5), 745-755. doi:10.1016/j.molcel.2016.05.003Lynch, M. (2010). Evolution of the mutation rate. Trends in Genetics, 26(8), 345-352. doi:10.1016/j.tig.2010.05.003Sanjuán, R., & Domingo-Calap, P. (2016). Mechanisms of viral mutation. Cellular and Molecular Life Sciences, 73(23), 4433-4448. doi:10.1007/s00018-016-2299-6Gago, S., Elena, S. F., Flores, R., & Sanjuan, R. (2009). Extremely High Mutation Rate of a Hammerhead Viroid. Science, 323(5919), 1308-1308. doi:10.1126/science.1169202Flores, R., Gago-Zachert, S., Serra, P., Sanjuán, R., & Elena, S. F. (2014). Viroids: Survivors from the RNA World? Annual Review of Microbiology, 68(1), 395-414. doi:10.1146/annurev-micro-091313-103416Flores, R., Minoia, S., Carbonell, A., Gisel, A., Delgado, S., López-Carrasco, A., … Di Serio, F. (2015). Viroids, the simplest RNA replicons: How they manipulate their hosts for being propagated and how their hosts react for containing the infection. Virus Research, 209, 136-145. doi:10.1016/j.virusres.2015.02.027Steger, G., & Perreault, J.-P. (2016). Structure and Associated Biological Functions of Viroids. Advances in Virus Research, 141-172. doi:10.1016/bs.aivir.2015.11.002Diener, T. O. (1989). Circular RNAs: relics of precellular evolution? Proceedings of the National Academy of Sciences, 86(23), 9370-9374. doi:10.1073/pnas.86.23.9370Ambrós, S., Hernández, C., & Flores, R. (1999). Rapid generation of genetic heterogeneity in progenies from individual cDNA clones of peach latent mosaic viroid in its natural host
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Reassessing Roman military activity through an interdisciplinary approach: Myth and archaeology in Laboreiro Mountain (Northwestern Iberia)
This is the final version. Available on open access from Elsevier via the DOI in this recordData availability:
Data will be made available on request.The present work aims at the archaeological characterisation and historical contextualisation of two large enclosures recently located through remote sensing in the Laboreiro Mountain on the border between Portugal and Galicia: Lomba do Mouro and Chaira da Maza. Ancient written sources, remote sensing, archaeological survey, and absolute dating will be combined in order to shed new light on these enclosures.
Given the specificity of the archaeological structures and contexts under study, the need to use complementary absolute dating methods will be discussed, including luminescence and radiocarbon dating. The results in the case of the Lomba do Mouro enclosure point to it possibly being a Roman military camp of late-Republican chronology.European Union Horizon 2020Fundação para a Ciência e TecnologiaFEDERLisboa Regional ProgrammeEuropean Regional Development Fund (FEEI
Genome Sequence of Brucella abortus Vaccine Strain S19 Compared to Virulent Strains Yields Candidate Virulence Genes
The Brucella abortus strain S19, a spontaneously attenuated strain, has been used as a vaccine strain in vaccination of cattle against brucellosis for six decades. Despite many studies, the physiological and molecular mechanisms causing the attenuation are not known. We have applied pyrosequencing technology together with conventional sequencing to rapidly and comprehensively determine the complete genome sequence of the attenuated Brucella abortus vaccine strain S19. The main goal of this study is to identify candidate virulence genes by systematic comparative analysis of the attenuated strain with the published genome sequences of two virulent and closely related strains of B. abortus, 9–941 and 2308. The two S19 chromosomes are 2,122,487 and 1,161,449 bp in length. A total of 3062 genes were identified and annotated. Pairwise and reciprocal genome comparisons resulted in a total of 263 genes that were non-identical between the S19 genome and any of the two virulent strains. Amongst these, 45 genes were consistently different between the attenuated strain and the two virulent strains but were identical amongst the virulent strains, which included only two of the 236 genes that have been implicated as virulence factors in literature. The functional analyses of the differences have revealed a total of 24 genes that may be associated with the loss of virulence in S19. Of particular relevance are four genes with more than 60bp consistent difference in S19 compared to both the virulent strains, which, in the virulent strains, encode an outer membrane protein and three proteins involved in erythritol uptake or metabolism
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