44 research outputs found

    Benchmarking the Security Protocol and Data Model (SPDM) for component authentication

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    Efforts to secure computing systems via software traditionally focus on the operating system and application levels. In contrast, the Security Protocol and Data Model (SPDM) tackles firmware level security challenges, which are much harder (if at all possible) to detect with regular protection software. SPDM includes key features like enabling peripheral authentication, authenticated hardware measurements retrieval, and secure session establishment. Since SPDM is a relatively recent proposal, there is a lack of studies evaluating its performance impact on real-world applications. In this article, we address this gap by: (1) implementing the protocol on a simple virtual device, and then investigating the overhead introduced by each SDPM message; and (2) creating an SPDM-capable virtual hard drive based on VirtIO, and comparing the resulting read/write performance with a regular, unsecured implementation. Our results suggest that SPDM bootstrap time takes the order of tens of milliseconds, while the toll of introducing SPDM on hard drive communication highly depends on specific workload patterns. For example, for mixed random read/write operations, the slowdown is negligible in comparison to the baseline unsecured setup. Conversely, for sequential read or write operations, the data encryption process becomes the bottleneck, reducing the performance indicators by several orders of magnitude.Comment: 10 pages, 8 figure

    Performance Evaluation of Cryptographic Algorithms over IoT Platforms and Operating Systems

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    The deployment of security services over Wireless Sensor Networks (WSN) and IoT devices brings significant processing and energy consumption overheads. These overheads are mainly determined by algorithmic efficiency, quality of implementation, and operating system. Benchmarks of symmetric primitives exist in the literature for WSN platforms but they are mostly focused on single platforms or single operating systems. Moreover, they are not up to date with respect to implementations and/or operating systems versions which had significant progress. Herein, we provide time and energy benchmarks of reference implementations for different platforms and operating systems and analyze their impact. Moreover, we not only give the first benchmark results of symmetric cryptography for the Intel Edison IoT platform but also describe a methodology of how to measure energy consumption on that platform

    Absence of stable collinear configurations in Ni(001)ultrathin films: canted domain structure as ground state

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    Brillouin light scattering (BLS) measurements were performed for (17-120) Angstrom thick Cu/Ni/Cu/Si(001) films. A monotonic dependence of the frequency of the uniform mode on an in-plane magnetic field H was observed both on increasing and on decreasing H in the range (2-14) kOe, suggesting the absence of a metastable collinear perpendicular ground state. Further investigation by magneto-optical vector magnetometry (MOKE-VM) in an unconventional canted-field geometry provided evidence for a domain structure where the magnetization is canted with respect to the perpendicular to the film. Spin wave calculations confirm the absence of stable collinear configurations.Comment: 6 pages, 3 figures (text, appendix and 1 figure added

    Low-Level Laser Application in the Early Myocardial Infarction Stage Has No Beneficial Role in Heart Failure

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    Low-level laser therapy (LLLT) has been targeted as a promising approach that can mitigate post infarction cardiac remodeling. There is some interesting evidence showing that the beneficial role of the LLLT could persist long-term even after the end of the application, but it remains to be systematically evaluated. Therefore, the present study aimed to test the hypothesis that LLLT beneficial effects in the early post-infarction cardiac remodeling could remain in overt heart failure even with the disruption of irradiations. Female Wistar rats were subjected to the coronary occlusion to induce myocardial infarction or Sham operation. A single LLLT application was carried out after 60 s and 3 days post-coronary occlusion, respectively. Echocardiography was performed 3 days and at the end of the experiment (5 weeks) to evaluate cardiac function. After the last echocardiographic examination. LV hemodynamic evaluation was performed at baseline and on sudden afterload increases. Compared with the Sham group, infarcted rats showed increased systolic and diastolic internal diameter as well as a depressed shortening fraction of LV. The only benefit of the LLLT was a higher shortening fraction after 3 days of infarction. However, treated-LLLT rats show a lower shortening fraction in the 5th week of study when compared with Sham and non-irradiated rats. A worsening of cardiac function was confirmed in the hemodynamic analysis as evidenced by the higher LV end-diastolic pressure and lower +dP/dt and dP/dt with five weeks of study. Cardiac functional reserve was also impaired by infarction as evidenced by an attenuated response of stroke work index and cardiac output to a sudden afterload stress, without LLLT repercussions. No significant differences were found in the myocardial expression of Akti NEGF pathway. Collectively, these findings illustrate that LLLT improves LV systolic function in the early post-infarction cardiac remodeling. However, this beneficial effect may be dependent on the maintenance of phototherapy. Long-term studies with LLLT application are needed to establish whether these effects ultimately translate into improved cardiac remodeling.Conselho Nacional de Desenvolvimento Cientifico e TecnologicoFAPESPNove de Julho Univ, Lab Biophoton, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Lab Cardiac Physiol, Sao Paulo, SP, BrazilNove de Julho Univ, Program Med, Sao Paulo, BrazilUniv Sao Judas Tadeu, Brazil Phys Educ & Aging Sci Program, Translat Physiol Lab, Sao Paulo, BrazilUniv Fed Sao Paulo, Lab Cardiac Physiol, Sao Paulo, SP, BrazilCNPq: 4400851/2014-8FAPESP: 09-54225/8FAPESP: 15/11028-9Web of Scienc

    The Hexamer Structure of the Rift Valley Fever Virus Nucleoprotein Suggests a Mechanism for its Assembly into Ribonucleoprotein Complexes

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    Rift Valley fever virus (RVFV), a Phlebovirus with a genome consisting of three single-stranded RNA segments, is spread by infected mosquitoes and causes large viral outbreaks in Africa. RVFV encodes a nucleoprotein (N) that encapsidates the viral RNA. The N protein is the major component of the ribonucleoprotein complex and is also required for genomic RNA replication and transcription by the viral polymerase. Here we present the 1.6 Å crystal structure of the RVFV N protein in hexameric form. The ring-shaped hexamers form a functional RNA binding site, as assessed by mutagenesis experiments. Electron microscopy (EM) demonstrates that N in complex with RNA also forms rings in solution, and a single-particle EM reconstruction of a hexameric N-RNA complex is consistent with the crystallographic N hexamers. The ring-like organization of the hexamers in the crystal is stabilized by circular interactions of the N terminus of RVFV N, which forms an extended arm that binds to a hydrophobic pocket in the core domain of an adjacent subunit. The conformation of the N-terminal arm differs from that seen in a previous crystal structure of RVFV, in which it was bound to the hydrophobic pocket in its own core domain. The switch from an intra- to an inter-molecular interaction mode of the N-terminal arm may be a general principle that underlies multimerization and RNA encapsidation by N proteins from Bunyaviridae. Furthermore, slight structural adjustments of the N-terminal arm would allow RVFV N to form smaller or larger ring-shaped oligomers and potentially even a multimer with a super-helical subunit arrangement. Thus, the interaction mode between subunits seen in the crystal structure would allow the formation of filamentous ribonucleocapsids in vivo. Both the RNA binding cleft and the multimerization site of the N protein are promising targets for the development of antiviral drugs

    Data standardization of plant-pollinator interactions

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    Background: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. Results: Here we present a vocabulary of terms and a data model for sharing plant–pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant–pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant–pollinator interactions. Conclusions: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant–pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant–pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of terms.Fil: Salim, José A. Universidade de Sao Paulo; BrasilFil: Saraiva, Antonio M.. Universidade de Sao Paulo; BrasilFil: Zermoglio, Paula Florencia. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Patagonia Norte. Instituto de Investigaciones En Recursos Naturales, Agroecologia y Desarrollo Rural. - Universidad Nacional de Rio Negro. Instituto de Investigaciones En Recursos Naturales, Agroecologia y Desarrollo Rural.; ArgentinaFil: Agostini, Kayna. Universidade Federal do São Carlos; BrasilFil: Wolowski, Marina. Universidade Federal de Alfenas; BrasilFil: Drucker, Debora P.. Empresa Brasileira de Pesquisa Agropecuaria (embrapa);Fil: Soares, Filipi M.. Universidade de Sao Paulo; BrasilFil: Bergamo, Pedro J.. Jardim Botânico do Rio de Janeiro; BrasilFil: Varassin, Isabela G.. Universidade Federal do Paraná; BrasilFil: Freitas, Leandro. Jardim Botânico do Rio de Janeiro; BrasilFil: Maués, Márcia M.. Empresa Brasileira de Pesquisa Agropecuaria (embrapa);Fil: Rech, Andre R.. Universidade Federal dos Vales do Jequitinhonha e Mucuri; BrasilFil: Veiga, Allan K.. Universidade de Sao Paulo; BrasilFil: Acosta, Andre L.. Instituto Tecnológico Vale; BrasilFil: Araujo, Andréa C. Universidade Federal do Mato Grosso do Sul; BrasilFil: Nogueira, Anselmo. Universidad Federal do Abc; BrasilFil: Blochtein, Betina. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Freitas, Breno M.. Universidade Estadual do Ceará; BrasilFil: Albertini, Bruno C.. Universidade de Sao Paulo; BrasilFil: Maia Silva, Camila. Universidade Federal Rural Do Semi Arido; BrasilFil: Nunes, Carlos E. P.. University of Stirling; BrasilFil: Pires, Carmen S. S.. Empresa Brasileira de Pesquisa Agropecuaria (embrapa);Fil: Dos Santos, Charles F.. Pontificia Universidade Católica do Rio Grande do Sul; BrasilFil: Queiroz, Elisa P.. Universidade de Sao Paulo; BrasilFil: Cartolano, Etienne A.. Universidade de Sao Paulo; BrasilFil: de Oliveira, Favízia F. Universidade Federal da Bahia; BrasilFil: Amorim, Felipe W.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Fontúrbel, Francisco E.. Pontificia Universidad Católica de Valparaíso; ChileFil: da Silva, Gleycon V.. Ministério da Ciência, Tecnologia, Inovações. Instituto Nacional de Pesquisas da Amazônia; BrasilFil: Consolaro, Hélder. Universidade Federal de Catalão; Brasi

    Data standardization of plant–pollinator interactions

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    Background: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. Results: Here we present a vocabulary of terms and a data model for sharing plant–pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant–pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant–pollinator interactions. Conclusions: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant–pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant–pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of termsinfo:eu-repo/semantics/publishedVersio

    Colorectal Cancer Stage at Diagnosis Before vs During the COVID-19 Pandemic in Italy

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    IMPORTANCE Delays in screening programs and the reluctance of patients to seek medical attention because of the outbreak of SARS-CoV-2 could be associated with the risk of more advanced colorectal cancers at diagnosis. OBJECTIVE To evaluate whether the SARS-CoV-2 pandemic was associated with more advanced oncologic stage and change in clinical presentation for patients with colorectal cancer. DESIGN, SETTING, AND PARTICIPANTS This retrospective, multicenter cohort study included all 17 938 adult patients who underwent surgery for colorectal cancer from March 1, 2020, to December 31, 2021 (pandemic period), and from January 1, 2018, to February 29, 2020 (prepandemic period), in 81 participating centers in Italy, including tertiary centers and community hospitals. Follow-up was 30 days from surgery. EXPOSURES Any type of surgical procedure for colorectal cancer, including explorative surgery, palliative procedures, and atypical or segmental resections. MAIN OUTCOMES AND MEASURES The primary outcome was advanced stage of colorectal cancer at diagnosis. Secondary outcomes were distant metastasis, T4 stage, aggressive biology (defined as cancer with at least 1 of the following characteristics: signet ring cells, mucinous tumor, budding, lymphovascular invasion, perineural invasion, and lymphangitis), stenotic lesion, emergency surgery, and palliative surgery. The independent association between the pandemic period and the outcomes was assessed using multivariate random-effects logistic regression, with hospital as the cluster variable. RESULTS A total of 17 938 patients (10 007 men [55.8%]; mean [SD] age, 70.6 [12.2] years) underwent surgery for colorectal cancer: 7796 (43.5%) during the pandemic period and 10 142 (56.5%) during the prepandemic period. Logistic regression indicated that the pandemic period was significantly associated with an increased rate of advanced-stage colorectal cancer (odds ratio [OR], 1.07; 95%CI, 1.01-1.13; P = .03), aggressive biology (OR, 1.32; 95%CI, 1.15-1.53; P < .001), and stenotic lesions (OR, 1.15; 95%CI, 1.01-1.31; P = .03). CONCLUSIONS AND RELEVANCE This cohort study suggests a significant association between the SARS-CoV-2 pandemic and the risk of a more advanced oncologic stage at diagnosis among patients undergoing surgery for colorectal cancer and might indicate a potential reduction of survival for these patients

    Conceptual Design of a Soft X‐ray SASE‐FEL Source

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    FELs based on SASE are believed to be powerful tools to explore the frontiers of basic sciences, from physics to chemistry to biology. Intense R&D programs have started in the USA and Europe in order to understand the SASE physics and to prove the feasibility of these sources. The allocation of considerable resources in the Italian National Research Plan (PNR) brought about the formation of a CNR‐ENEA‐INFN‐University of Roma "Tor Vergata" study group. A conceptual design study has been developed and possible schemes for linac sources have been investigated, bringing to the SPARX proposal. We report in this paper the results of a preliminary start to end simulation concerning one option we are considering based on an S‐band normal conducting linac with high brightness photoinjector integrated in a RF compressor

    Foot–Ground Interaction during Standing in Individuals with Down Syndrome: a Longitudinal Retrospective Study

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    In individuals with Down syndrome (DS) hypotonia and ligament laxity are characteristic features, which contribute to a number of orthopaedic issues, such as flat foot. The aim of this study was to quantify foot abnormalities in individuals with DS while standing, in terms of foot-ground interaction parameters (i.e. contact areas and plantar pressure distribution), from childhood to adulthood. Thirteen participants with DS were assessed using pedobarography in a time range of 17 years, from childhood to adulthood, and compared with healthy participants. Individuals with DS exhibited increases in all the sub-regions between childhood and adolescence, with significant reductions at an adult age. As for contact pressures, in healthy individuals changes in adolescence and adulthood were detected for all regions; in individuals with DS, significant increases in forefoot and rearfoot were observed only at adulthood. The pressures were systematically higher in healthy controls at all ages in rearfoot and in adolescence at forefoot, while individuals with DS exhibited higher pressure values in midfoot at childhood and adolescence. As one of the primary causes of flatfoot in DS is the presence of hypotonia and ligamentous laxity, which seem to persist especially in teens, it appears important to plan, starting from childhood, a specific rehabilitative program
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