167 research outputs found
Use of Circumferentially Cracked Bar sample for CTOD fracture toughness determination in the upper shelf regime
In this work, the use of circumferentially cracked bar (CCB) sample to determine material fracture toughness in the upper shelf regime for carbon steels has been investigated. Since high fracture toughness materials are known to exhibit extensive crack tip blunting before ductile crack initiation, accurate specimen design is required to provide realistic fracture toughness measurement. Here, a CCB was designed to have similar loss of constraint as for SENT sample. Continuum damage mechanics was used to predict the occurrence of ductile crack initiation and propagation. Finite element analysis was performed to predict specimen response and to compare computed J-integral crack driving force with measured CTOD. Finally, experimental tests were performed on X65 carbon steel and the measured critical CTOD was compared with available fracture data obtained with SENT
A sensor aided H.264 encoder tested on aerial imagery for SFM
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Standard video coding systems currently employed in UAV (Unmanned Aerial Vehicle) and aerial drone applications do not rely on some peculiarities in terms of scene 3D model and correlation among successive frames. In particular, the observed scene is static, i.e. the camera movement is dominant, and it can often be well approximated with a plane. Moreover, camera position and orientation can be obtained from the navigation system. Therefore, correspondent points on two video frames are linked by a simple homography. This paper presents novel results obtained by a low-complexity sensor aided H.264 encoder, recently developed at CIRA and yet tested on simulated data. The proposed encoder employs a new motion estimation scheme which make use of the global motion information provided by the onboard navigation system. The homography is used in order to initialize the block matching algorithm allowing a more robust motion estimation and a smaller search window, and hence reducing the complexity. The tests are made coding real aerial imagery, captured to be used for 3D scene reconstruction. The images are acquired by an high resolution camera mounted on a small drone, flying at low altitude
Multiple sclerosis treatment and melanoma development
Therapy of multiple sclerosis (MS) with disease-modifying agents such as natalizumab or fingolimod has been associated with the development of cutaneous melanoma. Here we briefly revise literature data and report of a case of a 48-year old woman who developed a melanoma and several atypical naevi after sub sequential treatment with natalizumab (1 year) and fingolimod (7 years). By immunohistochemistry we observed the presence of T cells and leukocyte infiltration as well as of vascular endothelial growth factor (VEGF)-A expression in the patient melanoma biopsy. Then, we analyzed proliferation, migration and VEGF-A expression in three melanoma cell lines and found out that both natalizumab and fingolimod inhibited tumor cell proliferation but promoted or blocked cell migration depending on the cell line examined. VEGF-A secretion was augmented in one melanoma cell line only after fingolimod treatment. In conclusion, our in vitro data do not support the hypothesis of a direct action of natalizumab or fingolimod on melanoma progression but acting on the tumor microenvironment these treatments could indirectly favor melanoma evolution
Thermal Pattern and Thermal Tracking: fingerprints of an environmental illicit
Abstract Being able to identify crime/guilty relationship is central to police investigation and new technologies enable authorities to do this faster and more accurately than ever before. In recent years, our research team has introduced the use of a range of aerial platforms and an innovative application of thermography to detect several illegal activities; for example illegal sanitary sewer and storm-drain connections, illicit discharges and other "anomalies" on the surface waters can be easily identified using their thermal infrared signatures. This paper introduces first results of a Thermal Pattern and Thermal Tracking approach, that can be used to identify different phenomena and several pollutants
IMPAcT-RLS2: Indagine nazionale sulla salute e la sicurezza sul lavoro: il ruolo dei Rappresentanti dei Lavoratori per la Sicurezza
L’Indagine IMPAcT-RLS2 si inserisce nel più
ampio programma di ricerca INSuLa2, la cui prima edizione,
condotta nel 2014 e rivolta a tutti gli attori della prevenzione,
ha approfondito aspetti della tutela della salute e sicurezza
sul lavoro (SSL) secondo il punto di vista delle varie figure
intervistate. La survey indirizzata ai Rappresentanti dei
lavoratori per la sicurezza (RLS), focalizzata inizialmente su
tre contesti regionali, è stata implementata grazie all’indagine
IMPAcT-RLS, realizzata nel 2016, che ha coinvolto un
campione di circa 2.100 soggetti, rappresentativo a livello
nazionale, per dimensione aziendale e settore di attivitĂ
economica. L’indagine ha evidenziato l’importanza di disporre
di informazioni sempre piĂą approfondite sul ruolo dei RLS
e di monitorarne l’andamento nel tempo. Il presente studio
ribadisce l’importanza di istituire rilevazioni periodiche
e replicabili, finalizzate ad aumentare le conoscenze e la
consapevolezza sui sistemi di prevenzione e promuovere
interventi sempre piĂą mirati per il miglioramento della tutela
della SSL.The IMPAcT-RLS2 survey is part of a larger
context of INSuLa2 research program; its first edition was
conducted in 2014 and targeted to all prevention professionals,
investigating occupational health and safety (OSH) protection
issues perceived by the various professionals’ point of view.
The survey addressed to Health and Safety Representatives
(HS reps.), focused on three regional contexts, was further
implemented in 2016 through the IMPAcT-RLS survey, which
involved a sample representative at national level, by company
size and economic activity sector consisting of about 2,100
subjects. The survey highlighted the importance of having ever
more in-depth information on the role of HS reps. and
monitoring their evolution over time. This study arises from
the need to create periodic and replicable surveys, aimed at
increasing knowledge and awareness of prevention systems
and promoting increasingly targeted interventions for improving
the protection of OS
A 48-week update of a multicentre real-life experience of dupilumab in adult patients with moderate-to-severe atopic dermatitis
The long-term efficacy and safety of dupilumab has been demonstrated in clinical trials and only in few real-world studies. We conducted an extension analysis from a previous 16-week study on 109 adult patients affected by moderate-to-severe atopic dermatitis treated with dupilumab. Eczema-Area-and-Severity-Index (EASI), itch numerical-rating-score (itch-NRS), Dermatology-Life-Quality-Index (DLQI) scores, drug survival rate and occurrence of adverse events after 24 and 48 weeks of dupilumab treatment were retrospectively collected. Dupilumab demonstrated sustained improvement of disease severity, pruritus, and quality of life in our series with an increasing percentage of patients gaining EASI75 and EASI90 response during the study period. Few patients interrupted treatment resulting in a very high drug survival rate. We also confirmed the favorable safety profile of the drug with absence of serious adverse events and serious infections throughout the 48-week period. The prevalence of conjunctivitis was low and mainly occurred in the mid-term with resolution of the majority of cases at 48 weeks
Secukinumab shows high efficacy irrespective of HLA-Cw6 status in patients with moderate-to-severe plaque-type psoriasis: SUPREME study
Background: Understanding genetic variations is important in predicting treatment response and forms the basis for identifying new pharmacogenetic and pharmacogenomic targets for psoriasis treatment. There are limited data on the efficacy of secukinumab in relation to genetic markers. Objectives: To evaluate the efficacy and safety of secukinumab 300 mg in HLA-Cw6-positive (Cw6-POS) and HLA-Cw6-negative (Cw6-NEG) patients with moderate-to-severe chronic plaque-type psoriasis. Methods: SUPREME was a 24-week, phase IIIb study with an extension period up to 72 weeks. Primary end point was Psoriasis Area Severity Index (PASI) 90 response rate after 16 weeks. Results: In total, 434 patients were recruited: 185 (42\ub76%) were Cw6-POS and 246 (56\ub77%) were Cw6-NEG (three not assessed). Mean \ub1 SD age was 45\ub72 \ub1 13\ub72 years (Cw6-POS 42\ub77 \ub1 13\ub71; Cw6-NEG 47\ub72 \ub1 12\ub79). The baseline PASI score was comparable between the cohorts [Cw6-POS 20\ub77 \ub1 8\ub799; Cw6-NEG 21\ub75 \ub1 9\ub799 (P = 0\ub7777)]. At week 16, PASI 90 was achieved in 80\ub74% of Cw6-POS and 79\ub77% of Cw6-NEG patients (difference 0\ub776; 95% confidence interval 127\ub704 to 8\ub723). No differences in absolute PASI at week 16 (Cw6-POS 1\ub736 \ub1 3\ub758; Cw6-NEG 1\ub718 \ub1 2\ub729) were observed. The overall safety profile of secukinumab was consistent with that previously reported. No statistically significant difference was detected in the rate of treatment-emergent adverse events [Cw6-POS 42\ub77%; Cw6-NEG 49\ub76% (P = 0\ub7295)]. A high PASI 90 response was achieved with secukinumab with a fast reduction in absolute PASI. Conclusions: Determination of HLA-Cw6 status for secukinumab therapy is unnecessary, as it is highly effective regardless of HLA-Cw6 status
Reconstructing extreme AMOC events through nudging of the ocean surface: a perfect model approach
While the Atlantic Meridional Overturning Circulation (AMOC) is thought to be a crucial component of the North Atlantic climate, past changes in its strength are challenging to quantify, and only limited information is available. In this study, we use a perfect model approach with the IPSL-CM5A-LR model to assess the performance of several surface nudging techniques in reconstructing the variability of the AMOC. Special attention is given to the reproducibility of an extreme positive AMOC peak from a preindustrial control simulation. Nudging includes standard relaxation techniques towards the sea surface temperature and salinity anomalies of this target control simulation, and/or the prescription of the wind-stress fields.
Surface nudging approaches using standard fixed restoring terms succeed in reproducing most of the target AMOC variability, including the timing of the extreme event, but systematically underestimate its amplitude. A detailed analysis of the AMOC variability mechanisms reveals that the underestimation of the extreme AMOC maximum comes from a deficit in the formation of the dense water masses in the main convection region, located south of Iceland in the model. This issue is largely corrected after introducing a novel surface nudging approach, which uses a varying restoring coefficient that is proportional to the simulated mixed layer depth, which, in essence, keeps the restoring time scale constant. This new technique substantially improves water mass transformation in the regions of convection, and in particular, the formation of the densest waters, which are key for the representation of the AMOC extreme. It is therefore a promising strategy that may help to better constrain the AMOC variability and other ocean features in the models. As this restoring technique only uses surface data, for which better and longer observations are available, it opens up opportunities for improved reconstructions of the AMOC over the last few decades
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Recent progress in understanding and predicting Atlantic decadal climate variability
Recent Atlantic climate prediction studies are an exciting new contribution to an extensive body of research on Atlantic decadal variability and predictability that has long emphasized the unique role of the Atlantic Ocean in modulating the surface climate. We present a survey of the foundations and frontiers in our understanding of Atlantic variability mechanisms, the role of the Atlantic Meridional Overturning Circulation (AMOC), and our present capacity for putting that understanding into practice in actual climate prediction systems
Dynamical attribution of oceanic prediction uncertainty in the North Atlantic: application to the design of optimal monitoring systems
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