78 research outputs found

    STUDIO DEL COMPORTAMENTO DI METALLI REFRATTARI AD ELEVATI STRAIN-RATE E TEMPERATURE

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    L’introduzione di acceleratori di particelle ad elevata energia, come il Large Hardon Collider (LHC) realizzato al CERN, ha richiesto lo sviluppo di metodi avanzati per predire il comportamento di particolari dispositivi che possono essere soggetti all’impatto con il fascio di particelle, e che, quindi, sono progettati per operare in un ambiente estremamente radioattivo e fortemente sollecitato da un punto di vista termo-strutturale. I materiali coinvolti devono soddisfare una serie di requisiti, quali: elevata resistenza, buona duttilità alle alte velocità di deformazione ed elevata stabilità alle alte temperature, oltre ad una buona resistenza alla corrosione e agli ambienti radioattivi. Ne deriva che i metalli refrattari e le loro leghe risultano essere degli ottimi canditati e lo studio del loro comportamento meccanico deve essere effettuato in un ampio intervallo di velocità di deformazione e di temperature

    Interactions of the SAP Domain of Human Ku70 with DNA Substrate: A Molecular Dynamics Study

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    NASA is developing a systems biology approach to improve the assessment of health risks associated with space radiation. The primary toxic and mutagenic lesion following radiation exposure is the DNA double strand break (DSB), thus a model incorporating proteins and pathways important in response and repair of this lesion is critical. One key protein heterodimer for systems models of radiation effects is the Ku70/80 complex. The Ku70/80 complex is important in the initial binding of DSB ends following DNA damage, and is a component of nonhomologous end joining repair, the primary pathway for DSB repair in mammalian cells. The SAP domain of Ku70 (residues 556-609), contains an a helix-extended strand-helix motif and similar motifs have been found in other nucleic acid-binding proteins critical for DNA repair. However, the exact mechanism of damage recognition and substrate specificity for the Ku heterodimer remains unclear in part due to the absence of a high-resolution structure of the SAP/DNA complex. We performed a series of molecular dynamics (MD) simulations on a system with the SAP domain of Ku70 and a 10 base pairs DNA duplex. Large-scale conformational changes were observed and some putative binding modes were suggested based on energetic analysis. These modes are consistent with previous experimental investigations. In addition, the results indicate that cooperation of SAP with other domains of Ku70/80 is necessary to explain the high affinity of binding as observed in experiments

    Wild cereal grain consumption among Early Holocene foragers of the Balkans predates the arrival of agriculture

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    Forager focus on wild cereal plants has been documented in the core zone of domestication in southwestern Asia, while evidence for forager use of wild grass grains remains sporadic elsewhere. In this paper, we present starch grain and phytolith analyses of dental calculus from 60 Mesolithic and Early Neolithic individuals from five sites in the Danube Gorges of the central Balkans. This zone was inhabited by likely complex Holocene foragers for several millennia before the appearance of the first farmers similar to 6200 cal BC. We also analyzed forager ground stone tools (GSTs) for evidence of plant processing. Our results based on the study of dental calculus show that certain species of Poaceae (species of the genus Aegi(ops) were used since the Early Mesolithic, while GSTs exhibit traces of a developed grass grain processing technology. The adoption of domesticated plants in this region after similar to 6500 cal BC might have been eased by the existing familiarity with wild cereals

    Medium and long-term efficacy of psychoeducational family intervention for bipolar I disorder: Results from a real-world, multicentric study

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    Objectives: This study aims to explore the long-term efficacy of a psychoeducational family intervention (PFI) in bipolar I disorder at one and five years post-intervention in terms of improvement of: (1) patients’ symptoms and global functioning and (2) relatives’ objective and subjective burden and coping strategies. Methods: This is a multicentre, real-world, controlled, outpatient trial. Recruited patients and key-relatives were consecutively allocated to the experimental intervention or treatment as usual. Patients were assessed at baseline, and after one and five years. Results: One hundred and thirty-seventh number families have been recruited; 70 have been allocated to the experimental intervention, and 67 have been allocated to the control group. We observed an increasing positive effect of the PFI on patients’ clinical status, global functioning and objective and subjective burden after one year. We also found a reduction in the levels of relatives’ objective and subjective burden and a significant improvement in the levels of perceived professional support and of coping strategies. The efficacy of PFI on patients’ clinical status was maintained at five years from the end of the intervention, in terms of relapses, hospitalizations and suicide attempts. Conclusions: The study showed that the provision of PFI in real-world settings is associated with a significant improvement of patients’ and relatives’ mental health and psychosocial functioning in the long term. We found that the clinical efficacy of the intervention, in terms of reduction of patients’ relapses, hospitalization and suicide attempts, persists after 5 years. It is advisable that PFI is provided to patients with BD I in routine practice

    Multipronged dental analyses reveal dietary differences in last foragers and first farmers at Grotta Continenza, central Italy (15,500–7000 BP)

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    This paper provides results from a suite of analyses made on human dental material from the Late Palaeolithic to Neolithic strata of the cave site of Grotta Continenza situated in the Fucino Basin of the Abruzzo region of central Italy. The available human remains from this site provide a unique possibility to study ways in which forager versus farmer lifeways affected human odonto-skeletal remains. The main aim of our study is to understand palaeodietary patterns and their changes over time as reflected in teeth. These analyses involve a review of metrics and oral pathologies, micro-fossils preserved in the mineralized dental plaque, macrowear, and buccal microwear. Our results suggest that these complementary approaches support the assumption about a critical change in dental conditions and status with the introduction of Neolithic foodstuff and habits. However, we warn that different methodologies applied here provide data at different scales of resolution for detecting such changes and a multipronged approach to the study of dental collections is needed for a more comprehensive and nuanced understanding of diachronic changes

    Off-label long acting injectable antipsychotics in real-world clinical practice: a cross-sectional analysis of prescriptive patterns from the STAR Network DEPOT study

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    Introduction Information on the off-label use of Long-Acting Injectable (LAI) antipsychotics in the real world is lacking. In this study, we aimed to identify the sociodemographic and clinical features of patients treated with on- vs off-label LAIs and predictors of off-label First- or Second-Generation Antipsychotic (FGA vs. SGA) LAI choice in everyday clinical practice. Method In a naturalistic national cohort of 449 patients who initiated LAI treatment in the STAR Network Depot Study, two groups were identified based on off- or on-label prescriptions. A multivariate logistic regression analysis was used to test several clinically relevant variables and identify those associated with the choice of FGA vs SGA prescription in the off-label group. Results SGA LAIs were more commonly prescribed in everyday practice, without significant differences in their on- and off-label use. Approximately 1 in 4 patients received an off-label prescription. In the off-label group, the most frequent diagnoses were bipolar disorder (67.5%) or any personality disorder (23.7%). FGA vs SGA LAI choice was significantly associated with BPRS thought disorder (OR = 1.22, CI95% 1.04 to 1.43, p = 0.015) and hostility/suspiciousness (OR = 0.83, CI95% 0.71 to 0.97, p = 0.017) dimensions. The likelihood of receiving an SGA LAI grew steadily with the increase of the BPRS thought disturbance score. Conversely, a preference towards prescribing an FGA was observed with higher scores at the BPRS hostility/suspiciousness subscale. Conclusion Our study is the first to identify predictors of FGA vs SGA choice in patients treated with off-label LAI antipsychotics. Demographic characteristics, i.e. age, sex, and substance/alcohol use co-morbidities did not appear to influence the choice towards FGAs or SGAs. Despite a lack of evidence, clinicians tend to favour FGA over SGA LAIs in bipolar or personality disorder patients with relevant hostility. Further research is needed to evaluate treatment adherence and clinical effectiveness of these prescriptive patterns

    DMTs and Covid-19 severity in MS: a pooled analysis from Italy and France

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    We evaluated the effect of DMTs on Covid-19 severity in patients with MS, with a pooled-analysis of two large cohorts from Italy and France. The association of baseline characteristics and DMTs with Covid-19 severity was assessed by multivariate ordinal-logistic models and pooled by a fixed-effect meta-analysis. 1066 patients with MS from Italy and 721 from France were included. In the multivariate model, anti-CD20 therapies were significantly associated (OR = 2.05, 95%CI = 1.39–3.02, p < 0.001) with Covid-19 severity, whereas interferon indicated a decreased risk (OR = 0.42, 95%CI = 0.18–0.99, p = 0.047). This pooled-analysis confirms an increased risk of severe Covid-19 in patients on anti-CD20 therapies and supports the protective role of interferon

    Experimental and theoretical study of 2,6-difluorophenylnitrene, its radical cation, and their rearrangement products in argon matrices

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    2,6-Difluorophenylnitrene was reinvestigated both experimentally, in Ar matrices at 10 K, and computationally, by DFT and CASSCF/CASPT2 calculations. Almost-pure samples of both neutral rearrangement products (the bicyclic azirine and the cyclic ketenimine) of a phenylnitrene were prepared and characterized for the first time. These samples were then subjected to X-irradiation in the presence of CH₂Cl₂ as an electron scavenger, which led to ionization of the neutral intermediates. Thereby, it was shown that only the phenylnitrene and the cyclic ketenimine yield stable radical cations, whereas the bicyclic azirine decays to both of these compounds on ionization. The cyclic ketenimine yields a novel aromatic azatropylium-type radical cation. The electronic structure of the title compound is discussed in detail, and its relation to those of the iso-π-electronic benzyl radical and phenylcarbene is traced

    Ultrafast Spectroscopic and Matrix Isolation Studies of <i>p-</i>Biphenylyl, <i>o</i>-Biphenylyl, and 1-Naphthylnitrenium Cations

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    p-Biphenylyl, o-biphenylyl, and 1-naphthyl azides were deposited in argon at low temperature in the presence and absence of HCl. In the absence of HCl, the known electronic and vibrational spectra of the corresponding triplet nitrenes, azirines, and didehydroazepines were observed, whereas in the presence of HCl, photolysis of these azides produces new electronic spectra assigned to the corresponding nitrenium cations. For p-biphenylyl azide the resulting spectrum of the nitrenium ion is very similar to the previously observed solution-phase spectrum of this species. The vibrational spectrum of this cation was recorded for the first time. Spectroscopic evidence for the previously unknown o-biphenylylnitrenium cation and 1-naphthylnitrenium cation are provided. The spectra of p- and o-biphenylylnitrenium cations and 1-naphthylnitrenium cation are well reproduced by CASSCF and CASPT2 calculations. The same nitrenium cations were detected in solution by femtosecond time-resolved laser flash photolysis of the appropriate azides in 88% formic acid. The transient spectra of the nitrenium cations recorded in solution are in good agreement with the spectra obtained in HCl matrices. The rates of formation of these cations equal the rates of decay of the singlet nitrenes in 88% formic acid and are as follows: p-biphenylyl (Ξgrowth = 11.5 ps), o-biphenylyl (Ξgrowth = 7.7 ps), and 1-naphthylnitrenium cations (Ξgrowth = 8.4 ps). The decay lifetimes of p- and o-biphenylylnitrenium cations are 50 and 27 ns, respectively. The decay lifetimes of 1-naphthylnitrenium cation is 860 ps in 88% formic acid
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