382 research outputs found

    Inhomogeneities on the surface of 21 Lutetia, the asteroid target of the Rosetta mission

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    CONTEXT: In July 2010 the ESA spacecraft Rosetta will fly-by the main belt asteroid 21 Lutetia. Several observations of this asteroid have been so far performed, but its surface composition and nature are still a matter of debate. For long time Lutetia was supposed to have a metallic nature due to its high IRAS albedo. Later on it has been suggested to have a surface composition similar to primitive carbonaceous chondrite meteorites, while further observations proposed a possible genetic link with more evolved enstatite chondrite meteorites. AIMS: In order to give an important contribution in solving the conundrum of the nature of Lutetia, in November 2008 we performed visible spectroscopic observations of this asteroid at the Telescopio Nazionale Galileo (TNG, La Palma, Spain). METHODS: Thirteen visible spectra have been acquired at different rotational phases. RESULTS: We confirm the presence of a narrow spectral feature at about 0.47-0.48 micron already found by Lazzarin et al. (2009) on the spectra of Lutetia. We also find a spectral feature at about 0.6 micron, detected by Lazzarin et al. (2004) on one of their Lutetia's spectra. More importantly, our spectra exhibit different spectral slopes between 0.6 and 0.75 micron and, in particular, we found that up to 20% of the Lutetia surface could have flatter spectra. CONCLUSIONS: We detected a variation of the spectral slopes at different rotational phases that could be interpreted as possibly due to differences in the chemical/mineralogical composition, as well as to inhomogeneities of the structure of the Lutetia's surface (e.g., the presence of craters or albedo spots) in the southern hemisphere.Comment: 3 pages, 2 figures. Accepted for publication in Astronomy and Astrophysics. Updated on 25 March 2010

    A novel microdosimeter based upon artificial single crystal diamond

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    The NEOShield-2 EU project: The Italian contribution

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    The NEOShield-2 (2015-2017) project has been recently approved by the European Commission in the framework of the Horizon 2020 programme with the aim i) to study specific technologies and instruments to conduct close approach missions to NEOs or to undertake mitigation demonstration, and ii) to acquire in-depth information of physical properties of the population of small NEOs (50-300 m), in order to design mitigation missions and assess the consequences of an impact on Earth. The Italian scientific community is widely involved in this project

    A longitudinal study on the information needs and preferences of patients after an acute coronary syndrome

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    Background: Research has shown that the provision of pertinent health information to patients with cardiovascular disease is associated with better adherence to medical prescriptions, behavioral changes, and enhanced perception of control over the disease. Yet there is no clear knowledge on how to improve information pertinence. Identifying and meeting the information needs of patients and their preferences for sources of information is pivotal to developing patient-led services. This prospective, observational study was aimed at exploring the information needs and perceived relevance of different information sources for patients during the twenty-four months following an acute coronary syndrome. Methods: Two hundred and seventeen newly diagnosed patients with acute coronary syndrome were enrolled in the study. The patients were primarily men (83.41 %) with a mean age of 57.28 years (range 35-75; SD = 7.98). Patients' needs for information and the perceived relevance of information sources were evaluated between 2 and 8 weeks after hospitalization (baseline) and during three follow-ups at 6, 12 and 24 months after baseline. Repeated measures ANOVA, Bonferroni post hoc tests and Cochran's Q Test were performed to test differences in variables of interest over time. Results: Results showed a reduction in information needs, but this decrease was significant only for topics related to daily activities, behavioral habits, risk and complication. At baseline, the primary sources of information were specialists and general practitioners, followed by family members and information leaflets given by physicians. Relevance of other sources changed differently over time. Conclusion: The present longitudinal study is an original contribution to the investigation of changes in information needs and preferences for sources of information among patients who are diagnosed with acute coronary syndrome. One of the main results of this study is that information on self-disease management is perceived as a minor theme for patients even two years after the event. Knowledge on how patients' information needs and perceived relevance of information sources change over time could enhance the quality of chronic disease management, leading health-care systems to move toward more patient-tailored care

    Stability and change of lifestyle profiles in cardiovascular patients after their first acute coronary event

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    Background: Acute coronary syndrome (ACS) is a major cause of morbidity and mortality. Lifestyle and health behavior changes play an important role in the primary and secondary prevention of ACS recurrence. Changes in unhealthy lifestyles after an acute coronary event have been analyzed by considering separate behaviors individually, even though research on the healthy population has demonstrated that unhealthy behaviors tend to co-occur. Purpose: The aim of this study was to identify lifestyle profiles of ACS patients and to explore their pathways of change for one year after their first coronary event by adopting a typological approach. Methods: Two hundred and twenty-three patients (84% male; mean age = 57.14) completed self-report measures of health-related behaviors at the beginning of cardiac rehabilitation, and six months and twelve months after. At each wave depression, anxiety and heart rate were also evaluated. Cluster analysis was performed to identify lifestyle profiles and to analyze their change over time. Differences in psychological factors and heart rate among clusters were assessed. Results: Patients’ diet, physical activity, and smoking behavior greatly improved six months after their first coronary event. No further improvements were detected after one year. At each wave specific lifestyle profiles were identified, ranging from more maladaptive to healthier clusters. Patients with multiple unhealthy behaviors experience greater difficulties in maintaining a healthier lifestyle over time. Moreover, the results demonstrated the association between lifestyle profiles at twelve months after the acute coronary event and depression measured six months earlier. Finally, the most maladaptive lifestyle profile had many members with elevated heart rate at twelve months after the cardiac rehabilitation. Conclusions: Current findings may have a strong practical impact in the development and implementation of personalized secondary prevention programs targeting lifestyles of ACS patients

    A type A and type D combined personality typology in essential hypertension and acute coronary syndrome patients: Associations with demographic, psychological, clinical, and lifestyle indicators

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    Many studies have focused on Type A and Type D personality types in the context of cardiovascular diseases (CVDs), but nothing is known about how these personality types combine to create new profiles. The present study aimed to develop a typology of Type A and Type D personality in two groups of patients affected by and at risk for coronary disease. The study involved 711 patients: 51.6% with acute coronary syndrome, 48.4% with essential hypertension (mean age = 56.4 years; SD = 9.7 years; 70.7% men). Cluster analysis was applied. External variables, such as socio-demographic, psychological, lifestyle, and clinical parameters, were assessed. Six groups, each with its own unique combined personality profile scores, were identified: Type D, Type A-Negatively Affected, Not Type A-Negatively Affected, Socially Inhibited-Positively Affected, Not Socially Inhibited, and Not Type A-Not Type D. The Type A-Negatively Affected cluster and, to a lesser extent, the Type D cluster, displayed the worst profile: namely higher total cardiovascular risk index, physical inactivity, higher anxiety and depression, and lower self-esteem, optimism, and health status. Identifying combined personality profiles is important in clinical research and practice in cardiovascular diseases. Practical implications are discussed

    Pre- and post-transplant minimal residual disease predicts relapse occurrence in children with acute lymphoblastic leukaemia

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    Relapse remains the leading cause of treatment failure in children with acute lymphoblastic leukaemia (ALL) undergoing allogeneic haematopoietic stem cell transplantation (HSCT). We retrospectively investigated the prognostic role of minimal residual disease (MRD) before and after HSCT in 119 children transplanted in complete remission (CR). MRD was measured by polymerase chain reaction in bone marrow samples collected pre-HSCT and during the first and third trimesters after HSCT (post-HSCT1 and post-HSCT3). The overall event-free survival (EFS) was 50%. The cumulative incidence of relapse and non-relapse mortality was 41% and 9%. Any degree of detectable pre-HSCT MRD was associated with poor outcome: EFS was 39% and 18% in patients with MRD positivity <1 Ã— 10−3 and ≥1 Ã— 10−3, respectively, versus 73% in MRD-negative patients (P < 0·001). This effect was maintained in different disease remissions, but low-level MRD had a very strong negative impact only in patients transplanted in second or further CR. Also, MRD after HSCT enabled patients to be stratified, with increasing MRD between post-HSCT1 and post-HSCT3 clearly defining cohorts with a different outcome. MRD is an important prognostic factor both before and after transplantation. Given that MRD persistence after HSCT is associated with dismal outcome, these patients could benefit from early discontinuation of immunosuppression, or pre-emptive immuno-therapy

    An Optimized Lentiviral Vector Efficiently Corrects the Human Sickle Cell Disease Phenotype

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    Autologous transplantation of hematopoietic stem cells transduced with a lentiviral vector (LV) expressing an anti-sickling HBB variant is a potential treatment for sickle cell disease (SCD). With a clinical trial as our ultimate goal, we generated LV constructs containing an anti-sickling HBB transgene (HBBAS3), a minimal HBB promoter, and different combinations of DNase I hypersensitive sites (HSs) from the locus control region (LCR). Hematopoietic stem progenitor cells (HSPCs) from SCD patients were transduced with LVs containing either HS2 and HS3 (\u3b2-AS3) or HS2, HS3, and HS4 (\u3b2-AS3 HS4). The inclusion of the HS4 element drastically reduced vector titer and infectivity in HSPCs, with negligible improvement of transgene expression. Conversely, the LV containing only HS2 and HS3 was able to efficiently transduce SCD bone marrow and Plerixafor-mobilized HSPCs, with anti-sickling HBB representing up to 3c60% of the total HBB-like chains. The expression of the anti-sickling HBB and the reduced incorporation of the \u3b2S-chain in hemoglobin tetramers allowed up to 50% reduction in the frequency of RBC sickling under hypoxic conditions. Together, these results demonstrate the ability of a high-titer LV to express elevated levels of a potent anti-sickling HBB transgene ameliorating the SCD cell phenotype
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