237 research outputs found

    Analysis of the Damage Evolution in Steel Specimens under Tension by Means of XRCT

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    When a steel specimen is tested under tension, damage usually develops evenly all along the specimen, finally necking and leading to the typical cup-cone fracture surface. Nevertheless, some steels present an unusual fracture pattern consisting on a plane fracture surface with a dark region in the centre of the fracture zone. In this contribution, the authors analyse the evolution of the internal damage by using X-ray computed tomography (XRCT) on 3mm-diametre specimens of two steels. The specimens are tested in subsequent loading steps, after each of which it is unloaded and analysed with XRCT. This procedure helps to identify the evolution of damage developed inside each specimen at predefined strain levels. XRCT reveals a very high initial porosity in the material with the cup-cone fracture pattern and a very low initial porosity in the other. In the latter, fracture is triggered by a concentrated internal damage that can be seen as an internal notch which produces a stress concentration that leads to the eventual failure

    Effects of Osteopathic Visceral Treatment in Patients with Gastroesophageal Reflux: A Randomized Controlled Trial

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    Osteopathic manual treatment has been recommended as a non-pharmacological therapy for Gastroesophageal Reflux Disease (GERD). However, to date, no study has supported the effectiveness of this intervention with respect to the symptoms of the disease. Our goal was to assess the effect of an osteopathic manual technique for the lower esophageal sphincter on GERD symptoms, cervical mobility and on the C4 spinous process pressure pain threshold (PPTs). Methods: A randomized, double-blind placebo-controlled trial was performed. Sixty subjects suffering from GERD participated in this study and were randomly assigned to either an experimental group (EG) (n = 29), who received the osteopathic technique for the lower esophageal sphincter, or to a control group (CG) (n = 31), who received a manual contact, which mimicked the osteopathic technique without exerting any therapeutic force. Randomization was computer-generated, with allocation concealed by sequentially numbered, opaque, sealed envelopes. The GerdQ questionnaire was used to assess symptom changes the week after intervention. Cervical Range of Motion (CROM) and algometer were used to evaluate cervical mobility and PPTs before and after both treatments. Before–after between groups comparison (t-test) was used for statistical analysis of the outcome, with two measurement points (GerdQ), while repeated-measures ANOVA was used for those outcomes with four measurement points (CROM and PPT). Results: The application of the osteopathic manual treatment in subjects with GERD produced a significant improvement in symptoms one week after the intervention (p = 0.005) with a between-groups difference of 1.49 points in GerdQ score (95% CI: 0.47–2.49). PPT C4 improved in the EG after the treatment (p = 0.034; η 2 = 0.048) (between-groups difference 8.78 Newton/cm2 ; 95% CI: 0.48–17.09). CROM also increased in the EG compared to the CG (p < 0.001; η 2 = 0.108) (between-groups difference 33.89 degrees; 95% CI: 15.17–52.61). Conclusions: The manual osteopathic technique produces an improvement in GERD symptoms one week after treatment, cervical mobility, and PPTs. This may mean that osteopathic treatment is useful for improving symptoms of GER

    Electronic and electrocatalytic properties of PbTiO3: unveiling the effect of strain and oxygen vacancy

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    First-principles calculations based on density-functional theory have been used to investigate the effect of biaxial strain and oxygen vacancy on the electronic, photocatalytic, and electrocatalytic properties of PbTiO3 oxide. Our results show that PbTiO3 has a high exciton binding energy and a band gap that can be easily moderated with different strain regimes. From a reactivity viewpoint, the highly exothermic adsorption of hydrogen atoms in both pristine and strained PbTiO3 structures does not make it a potential electrocatalyst for the hydrogen evolution reaction. Fortunately, the presence of oxygen vacancies on the PbTiO3 surface induces moderate adsorption energies, making the reduced PbTiO3 suitable for hydrogen evolution reaction processes

    Olive oil and prevention of chronic diseases: summary of an International conference

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    Olive oil is the foremost source of fat in the Mediterranean area and, among other features, sets the Mediterranean diet apart from other dietary regimens. In January 2018, the International Olive Council convened several worldwide experts at the Robert Mondavi Institute (Davis, CA), to discuss and summarize the available data on the effects of olive oil consumption on human health. In this paper, we critically provide a synthesis of the main reported findings, which underscore how and why consuming this oil as part of a balanced diet and healthful lifestyle improves prognosis and extends life- and health-spans

    Truncation-Driven Lateral Association of &alpha;-Synuclein Hinders Amyloid Clearance by the Hsp70-Based Disaggregase

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    The aggregation of α-synuclein is the hallmark of a collective of neurodegenerative disorders known as synucleinopathies. The tendency to aggregate of this protein, the toxicity of its aggregation intermediates and the ability of the cellular protein quality control system to clear these intermediates seems to be regulated, among other factors, by post-translational modifications (PTMs). Among these modifications, we consider herein proteolysis at both the N- and C-terminal regions of α-synuclein as a factor that could modulate disassembly of toxic amyloids by the human disaggregase, a combination of the chaperones Hsc70, DnaJB1 and Apg2. We find that, in contrast to aggregates of the protein lacking the N-terminus, which can be solubilized as efficiently as those of the WT protein, the deletion of the C-terminal domain, either in a recombinant context or as a consequence of calpain treatment, impaired Hsc70-mediated amyloid disassembly. Progressive removal of the negative charges at the C-terminal region induces lateral association of fibrils and type B* oligomers, precluding chaperone action. We propose that truncation-driven aggregate clumping impairs the mechanical action of chaperones, which includes fast protofilament unzipping coupled to depolymerization. Inhibition of the chaperone-mediated clearance of C-truncated species could explain their exacerbated toxicity and higher propensity to deposit found in vivo.This work was supported by grants PID2019-111068GB-I00 (to A.M.) (AEI/FEDER, UE) and PID2019-105872GB-I00 (to J.M.V.) (AEI/FEDER, UE) from the Ministry of Science and Innovation and by the Basque Government (grant IT1201-19 to AM). The Centro Nacional de Biotecnología (CNB) is a Severo Ochoa Center of Excellence (MINECO award SEV 2017-0712). N.O. holds a contract funded by Fundacion Biofisika Bizkaia. Acknowledgment

    KSHV LANA acetylation-selective acidic domain reader sequence mediates virus persistence

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    Viruses modulate biochemical cellular pathways to permit infection. A recently described mechanism mediates selective protein interactions between acidic domain readers and unacetylated, lysine-rich regions, opposite of bromodomain function. Kaposi´s sarcoma (KS)-associated herpesvirus (KSHV) is tightly linked with KS, primary effusion lymphoma, and multicentric Castleman’s disease. KSHV latently infects cells, and its genome persists as a multicopy, extrachromosomal episome. During latency, KSHV expresses a small subset of genes, including the latency-associated nuclear antigen (LANA), which mediates viral episome persistence. Here we show that LANA contains two tandem, partially overlapping, acidic domain sequences homologous to the SET oncoprotein acidic domain reader. This domain selectively interacts with unacetylated p53, as evidenced by reduced LANA interaction after overexpression of CBP, which acetylates p53, or with an acetylation mimicking carboxyl-terminal domain p53 mutant. Conversely, the interaction of LANA with an acetylation-deficient p53 mutant is enhanced. Significantly, KSHV LANA mutants lacking the acidic domain reader sequence are deficient for establishment of latency and persistent infection. This deficiency was confirmed under physiological conditions, on infection of mice with a murine gammaherpesvirus 68 chimera expressing LANA, where the virus was highly deficient in establishing latent infection in germinal center B cells. Therefore, LANA’s acidic domain reader is critical for viral latency. These results implicate an acetylation-dependent mechanism mediating KSHV persistence and expand the role of acidic domain readers.info:eu-repo/semantics/publishedVersio

    Agreement, case and locality in the nominal and verbal domains

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    This book explores the Agree operation and its morphological realisations (agreement and case), specifically focusing on the connection between Agree and other syntactic dependencies such as movement, binding and control. The chapters in this volume examine a diverse set of cross-linguistic phenomena involving agreement and case from a variety of theoretical perspectives, with a view to elucidating the nature of the abstract operations that underlie them. The phenomena discussed include backward control, passivisation, progressive aspectual constructions, extraction from nominals, possessives, relative clauses and the phasal status of PPs

    Agreement, case and locality in the nominal and verbal domains

    Get PDF
    This book explores the Agree operation and its morphological realisations (agreement and case), specifically focusing on the connection between Agree and other syntactic dependencies such as movement, binding and control. The chapters in this volume examine a diverse set of cross-linguistic phenomena involving agreement and case from a variety of theoretical perspectives, with a view to elucidating the nature of the abstract operations that underlie them. The phenomena discussed include backward control, passivisation, progressive aspectual constructions, extraction from nominals, possessives, relative clauses and the phasal status of PPs
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