66 research outputs found
A Methodology for the Characterisation of Leakages in Combinatorial Logic
Glitches represent a great danger for hardware implementations of cryptographic schemes. Their intrinsic random nature makes them difficult to tackle and their occurrence threatens side-channel protections. Although countermeasures aiming at structurally solving the problem already exist, they usually require some effort to be applied or introduce non-negligible overhead in the design. Our work addresses the gap between such countermeasures and the naïve implementation of schemes being vulnerable in the presence of glitches. Our contribution is twofold: (1) we expand the mathematical framework proposed by Brzozowski and Esik (FMSD 2003) by meaningfully adding the ´ notion of information leakage, (2) thanks to which we define a formal methodology for the analysis of vulnerabilities in combinatorial circuits when glitches are taken into account
Information-Driven Gas Distribution Mapping for Autonomous Mobile Robots.
The ability to sense airborne pollutants with mobile robots provides a valuable asset for domains such as industrial safety and environmental monitoring. Oftentimes, this involves detecting how certain gases are spread out in the environment, commonly referred to as a gas distribution map, to subsequently take actions that depend on the collected information. Since the majority of gas transducers require physical contact with the analyte to sense it, the generation of such a map usually involves slow and laborious data collection from all key locations. In this regard, this paper proposes an efficient exploration algorithm for 2D gas distribution mapping with an autonomous mobile robot. Our proposal combines a Gaussian Markov random field estimator based on gas and wind flow measurements, devised for very sparse sample sizes and indoor environments, with a partially observable Markov decision process to close the robot’s control loop. The advantage of this approach is that the gas map is not only continuously updated, but can also be leveraged to choose the next location based on how much information it provides. The exploration consequently adapts to how the gas is distributed during run time, leading to an efficient sampling path and, in turn, a complete gas map with a relatively low number of measurements. Furthermore, it also accounts for wind currents in the environment, which improves the reliability of the final gas map even in the presence of obstacles or when the gas distribution diverges from an ideal gas plume. Finally, we report various simulation experiments to evaluate our proposal against a computer-generated fluid dynamics ground truth, as well as physical experiments in a wind tunnel.Partial funding for open access charge: Universidad de Málag
Antiviral and antioxidant activity of a hydroalcoholic extract from Humulus lupulus L.
A hydroalcoholic extract from female inflorescences of Humulus lupulus L. (HOP extract) was evaluated for its anti-influenza activity. The ability of the extract to interfere with different phases of viral replication was assessed, as well as its effect on the intracellular redox state, being unbalanced versus the oxidative state in infected cells. The radical scavenging power, inhibition of lipoperoxidation, and ferric reducing activity were assayed as antioxidant mechanisms. A phytochemical characterization of the extract was also performed. We found that HOP extract significantly inhibited replication of various viral strains, at different time from infection. Viral replication was partly inhibited when virus was incubated with extract before infection, suggesting a direct effect on the virions. Since HOP extract was able to restore the reducing conditions of infected cells, by increasing glutathione content, its antiviral activity might be also due to an interference with redox-sensitive pathways required for viral replication. Accordingly, the extract exerted radical scavenging and reducing effects and inhibited lipoperoxidation and the tBOOH-induced cytotoxicity. At phytochemical analysis, different phenolics were identified, which altogether might contribute to HOP antiviral effect. In conclusion, our results highlighted anti-influenza and antioxidant properties of HOP extract, which encourage further in vivo studies to evaluate its possible application
Generation of functional HLA-DR*1101 tetramers receptive for loading with pathogen or tumour derived synthetic peptides
BACKGROUND: MHC class I-peptide tetramers are currently utilised to characterize CD8(+ )T cell responses at single cell level. The generation and use of MHC class II tetramers to study antigen-specific CD4(+ )T cells appears less straightforward. Most MHC class II tetramers are produced with a homogeneously built-in peptide, reducing greatly their flexibility of use. We attempted the generation of "empty" functional HLA-DR*1101 tetramers, receptive for loading with synthetic peptides by incubation. No such reagent is in fact available for this HLA-DR allele, one of the most frequent in the Caucasian population. RESULTS: We compared soluble MHC class II-immunoglobulin fusion proteins (HLA-DR*1101-Ig) with soluble MHC class II protein fused with an optimised Bir site for enzymatic biotynilation (HLA-DR*1101-Bir), both produced in insect cells. The molecules were multimerised by binding fluorochrome-protein A or fluorochrome-streptavidin, respectively. We find that HLA-DR*1101-Bir molecules are superior to the HLA-DR*1101-Ig ones both in biochemical and functional terms. HLA-DR*1101-Bir molecules can be pulsed with at least three different promiscuous peptide epitopes, derived from Tetanus Toxoid, influenza HA and the tumour associated antigen MAGE-3 respectively, to stain specific CD4(+ )T cells. Both staining temperature and activation state of CD4(+ )T cells are critical for the binding of peptide-pulsed HLA-DR*1101-Bir to the cognate TCR. CONCLUSION: It is therefore possible to generate a soluble recombinant HLA-DR*1101 backbone that is receptive for loading with different peptides to stain specific CD4(+ )T cells. As shown for other HLA-DR alleles, we confirm that not all the strategies to produce soluble HLA-DR*1101 multimers are equivalent
SARS-CoV-2 Circulation in the School Setting: A Systematic Review and Meta-Analysis
The contribution of children to viral spread in schools is still debated. We conducted a systematic review and meta-analysis of studies to investigate SARS-CoV-2 transmission in the school setting. Literature searches on 15 May 2021 yielded a total of 1088 publications, including screening, contact tracing, and seroprevalence studies. MOOSE guidelines were followed, and data were analyzed using random-effects models. From screening studies involving more than 120,000 subjects, we estimated 0.31% (95% confidence interval (CI) 0.05–0.81) SARS-CoV-2 point prevalence in schools. Contact tracing studies, involving a total of 112,622 contacts of children and adults, showed that onward viral transmission was limited (2.54%, 95% CI 0.76–5.31). Young index cases were found to be 74% significantly less likely than adults to favor viral spread (odds ratio (OR) 0.26, 95% CI 0.11–0.63) and less susceptible to infection (OR 0.60; 95% CI 0.25–1.47). Lastly, from seroprevalence studies, with a total of 17,879 subjects involved, we estimated that children were 43% significantly less likely than adults to test positive for antibodies (OR 0.57, 95% CI 0.49–0.68). These findings may not applied to the Omicron phase, we further planned a randomized controlled trial to verify these results
SARS-CoV-2 Circulation in the School Setting: A Systematic Review and Meta-Analysis
The contribution of children to viral spread in schools is still debated. We conducted a systematic review and meta-analysis of studies to investigate SARS-CoV-2 transmission in the school setting. Literature searches on 15 May 2021 yielded a total of 1088 publications, including screening, contact tracing, and seroprevalence studies. MOOSE guidelines were followed, and data were analyzed using random-effects models. From screening studies involving more than 120,000 subjects, we estimated 0.31% (95% confidence interval (CI) 0.05–0.81) SARS-CoV-2 point prevalence in schools. Contact tracing studies, involving a total of 112,622 contacts of children and adults, showed that onward viral transmission was limited (2.54%, 95% CI 0.76–5.31). Young index cases were found to be 74% significantly less likely than adults to favor viral spread (odds ratio (OR) 0.26, 95% CI 0.11–0.63) and less susceptible to infection (OR 0.60; 95% CI 0.25–1.47). Lastly, from seroprevalence studies, with a total of 17,879 subjects involved, we estimated that children were 43% significantly less likely than adults to test positive for antibodies (OR 0.57, 95% CI 0.49–0.68). These findings may not applied to the Omicron phase, we further planned a randomized controlled trial to verify these results
Association of CTLA-4 gene variants with response to therapy and long-term survival in metastatic melanoma patients treated with ipilimumab: An Italian melanoma intergroup study
Consensus based recommendations for diagnosis and medical management of Poland syndrome (sequence)
Background Poland syndrome (OMIM: 173800) is a disorder in which affected individuals are born with missing or underdeveloped muscles on one side of the body, resulting in abnormalities that can affect the chest, breast, shoulder, arm, and hand. The extent and severity of the abnormalities vary among affected individuals. Main body The aim of this work is to provide recommendations for the diagnosis and management of people affected by Poland syndrome based on evidence from literature and experience of health professionals from different medical backgrounds who have followed for several years affected subjects. The literature search was performed in the second half of 2019. Original papers, meta-analyses, reviews, books and guidelines were reviewed and final recommendations were reached by consensus. Conclusion Being Poland syndrome a rare syndrome most recommendations here presented are good clinical practice based on the consensus of the participant experts
The adhesion molecule L1 regulates transendothelial migration and trafficking of dendritic cells
The adhesion molecule L1, which is extensively characterized in the nervous
system, is also expressed in dendritic cells (DCs), but its function there has
remained elusive. To address this issue, we ablated L1 expression in DCs of
conditional knockout mice. L1-deficient DCs were impaired in adhesion to and
transmigration through monolayers of either lymphatic or blood vessel
endothelial cells, implicating L1 in transendothelial migration of DCs. In
agreement with these findings, L1 was expressed in cutaneous DCs that migrated
to draining lymph nodes, and its ablation reduced DC trafficking in vivo. Within
the skin, L1 was found in Langerhans cells but not in dermal DCs, and L1
deficiency impaired Langerhans cell migration. Under inflammatory conditions, L1
also became expressed in vascular endothelium and enhanced transmigration of
DCs, likely through L1 homophilic interactions. Our results implicate L1 in the
regulation of DC trafficking and shed light on novel mechanisms underlying
transendothelial migration of DCs. These observations might offer novel
therapeutic perspectives for the treatment of certain immunological
disorders
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