723 research outputs found

    A highly-collimated SiO jet in the HH212 protostellar outflow

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    We mapped the HH212 Class 0 outflow in SiO(2--1, 5--4) and continuum using the PdBI in its extended configurations. The unprecedented angular resolution (down to 0.34") allows accurate comparison with a new, deep H2 image obtained at the VLT. The SiO emission is confined to a highly-collimated bipolar jet (width 0.35") along the outflow axis. The jet can be traced down to within 500 AU of the protostar, in a region that is heavily obscured in H2 images. Where both species are detected, SiO shows the same overall kinematics and structure as H2, indicating that both molecules are tracing the same material. We find that the high-velocity SiO gas near the protostar is not tracing a wide-angle wind but is already confined to a flow inside a narrow cone of half-opening angle < 6 deg.Comment: Astronomy and Astrophysics Letter, in pres

    Sensor-Based Task Ergonomics Feedback for a Passive Low-Back Exoskeleton

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    Low-back exoskeletons are a wide-spreading technology tackling low-back pain, the leading work-related musculoskeletal disorder in many work sectors. Currently, spring-based (i.e., passive) exoskeletons are the mostly adopted in the industry, being cheaper and generally less complex and more intuitive to use. We introduce a system of interconnected wireless sensing units to provide online ergonomics feedback to the wearer. We integrate the system into our passive low-back exoskeleton and evaluate its usability with healthy volunteers and potential end users. In this way, we provide the exoskeleton with a tool aimed both at monitoring the interaction of the system with the user, providing them with an ergonomics feedback during task execution. The sensor system can also be integrated with a custom-developed Unity3D application which can be used to interface with Augmented- or Virtual-Reality applications with higher potential for improved user feedback, ergonomics training, and offline ergonomics evaluation of the workplace. We believe that providing ergonomics feedback to exoskeleton users in the industrial sector could help further reduce the drastic impact of low-back pain and prevent its onset

    Agrammatic but numerate

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    A central question in cognitive neuroscience concerns the extent to which language enables other higher cognitive functions. In the case of mathematics, the resources of the language faculty, both lexical and syntactic, have been claimed to be important for exact calculation, and some functional brain imaging studies have shown that calculation is associated with activation of a network of left-hemisphere language regions, such as the angular gyrus and the banks of the intraparietal sulcus. We investigate the integrity of mathematical calculations in three men with large left-hemisphere perisylvian lesions. Despite severe grammatical impairment and some difficulty in processing phonological and orthographic number words, all basic computational procedures were intact across patients. All three patients solved mathematical problems involving recursiveness and structure-dependent operations (for example, in generating solutions to bracket equations). To our knowledge, these results demonstrate for the first time the remarkable independence of mathematical calculations from language grammar in the mature cognitive system

    Generation of a Synthetic Human Chromosome with Two Centromeric Domains for Advanced Epigenetic Engineering Studies

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    It is generally accepted that chromatin containing the histone H3 variant CENP-A is an epigenetic mark maintaining centromere identity. However, the pathways leading to the formation and maintenance of centromere chromatin remain poorly characterized due to difficulties of analysis of centromeric repeats in native chromosomes. To address this problem, in our previous studies we generated a human artificial chromosome (HAC) whose centromere contains a synthetic alpha-satellite (alphoid) DNA array containing the tetracycline operator, the alphoid<sup>tetO</sup>-HAC. The presence of tetO sequences allows the specific targeting of the centromeric region in the HAC with different chromatin modifiers fused to the tetracycline repressor. The alphoid<sup>tetO</sup>-HAC has been extensively used to investigate protein interactions within the kinetochore and to define the epigenetic signature of centromeric chromatin to maintain a functional kinetochore. In this study, we developed a novel synthetic HAC containing two alphoid DNA arrays with different targeting sequences, tetO, lacO and gal4, the alphoid<sup>hybrid</sup>-HAC. This new HAC can be used for detailed epigenetic engineering studies because its kinetochore can be simultaneously or independently targeted by different chromatin modifiers and other fusion proteins

    Analysis of BRCA1 and RAD51C promoter methylation in italian families at high-risk of breast and ovarian cancer

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    Previous studies on breast and ovarian carcinoma (BC and OC) revealed constitutional BRCA1 and RAD51C promoter hypermethylation as epigenetic alterations leading to tumor predisposition. Nevertheless, the impact of epimutations at these genes is still debated. One hundred and eight women affected by BC, OC, or both and considered at very high risk of carrying BRCA1 germline mutations were studied. All samples were negative for pathogenic variants or variants of uncertain significance at BRCA testing. Quantitative BRCA1 and RAD51C promoter methylation analyses were performed by Epityper mass spectrometry on peripheral blood samples and results were compared with those in controls. All the 108 analyzed cases showed methylation levels at the BRCA1/RAD51C promoter comparable with controls. Mean methylation levels (\ub1 stdev) at the BRCA1 promoter were 4.3% (\ub1 1.4%) and 4.4% (\ub1 1.4%) in controls and patients, respectively (p &gt; 0.05; t-test); mean methylation levels (\ub1 stdev) at the RAD51C promoter were 4.3% (\ub1 0.9%) and 3.7% (\ub1 0.9%) in controls and patients, respectively (p &gt; 0.05; t-test). Based on these observations; the analysis of constitutional methylation at promoters of these genes does not seem to substantially improve the definition of cancer risks in patients. These data support the idea that epimutations represent a very rare event in high-risk BC/OC populations

    Hypercoagulability of COVID-19 patients in Intensive Care Unit: A Report of Thromboelastography Findings and other Parameters of Hemostasis

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    BACKGROUND: The severe inflammatory state secondary to Covid-19 leads to a severe derangement of hemostasis that has been recently described as a state of disseminated intravascular coagulation (DIC) and consumption coagulopathy, defined as decreased platelet count, increased fibrin(ogen) degradation products such as D-dimer as well as low fibrinogen. AIMS: Whole blood from 24 patients admitted at the intensive care unit because of Covid-19 was collected and evaluated with thromboelastography by the TEG point-of-care device on a single occasion and six underwent repeated measurements on two consecutive days for a total of 30 observations. Plasma was evaluated for the other parameters of hemostasis. RESULTS: TEG parameters are consistent with a state of hypercoagulability as shown by decreased R and K values, and increased values of K angle and MA. Platelet count was normal or increased, prothrombin time and activated partial thromboplastin time were near(normal). Fibrinogen was increased and D-dimer was dramatically increased. C-reactive protein was increased. Factor VIII and von Willebrand factor (n=11) were increased. Antithrombin (n=11) was marginally decreased and protein C (n=11) was increased. CONCLUSION: The results of this cohort of patients with Covid-19 are not consistent with acute DIC, rather they support hypercoagulability together with a severe inflammatory state. These findings may explain the events of venous thromboembolism observed in some of these patients and support antithrombotic prophylaxis/treatment. Clinical trials are urgently needed to establish the type of drug, dosage and optimal duration of prophylaxis
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