416 research outputs found

    Imaging cardiac fat

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    DARE: evaluating Data Accuracy using node REputation

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    Typical wireless sensor networks (WSNs) applications are characterized by a certain number of different requirements such as: data accuracy, localization, reputation, security, and confidentiality. Moreover, being often battery powered, WSNs face the challenge of ensuring privacy and security despite power consumption limitations. When the application scenario allows their use, data aggregation techniques can significantly reduce the amount of data exchanged over the wireless link at the price of an increased computational complexity and the potential exposition to data integrity risks in the presence of malicious nodes. In this paper, we propose DARE, an hybrid architecture combining WSNs with the wireless mesh networking paradigm in order to provide secure data aggregation and node reputation in WSNs. Finally, the use of a secure verifiable multilateration technique allows the network to retain the trustworthiness of aggregated data even in the presence of malicious node. Extensive performance evaluations carried out using simulations as well as a real-world prototype implementation, show that DARE can effectively reduce the amount of data exchanged over the wireless medium delivering up to 50% battery lifetime improvement to the wireless sensors

    Performance Evaluation of an Hybrid Mesh and Sensor Network

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    Incremental value of contrast myocardial perfusion to detect intermediate versus severe coronary artery stenosis during stress-echocardiography

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    <p>Abstract</p> <p>Background</p> <p>We aimed to compare the incremental value of contrast myocardial perfusion imaging (MPI) for the detection of intermediate versus severe coronary artery stenosis during dipyridamole-atropine echocardiography (DASE).</p> <p>Wall motion (WM) assessment during stress-echocardiography demonstrates suboptimal sensitivity to detect coronary artery disease (CAD), particularly in patients with isolated intermediate (50%-70%) coronary stenosis.</p> <p>Methods</p> <p>We performed DASE with MPI in 150 patients with a suspected chest pain syndrome who were given clinical indication to coronary angiography.</p> <p>Results and discussion</p> <p>When CAD was defined as the presence of a ≥50% stenosis, the addition of MPI increased sensitivity (+30%) and decreased specificity (-14%), with a final increase in total diagnostic accuracy (+16%, p < 0.001). The addition of MPI data substantially increased the sensitivity to detect patients with isolated intermediate stenosis from 37% to 98% (p < 0.001); the incremental sensitivity was much lower in patients with severe stenosis, from 85% to 96% (p < 0.05), at the expense of a higher decrease in specificity and a final decrease in total diagnostic accuracy (-18%, p < 0.001).</p> <p>Conclusions</p> <p>The addition of MPI on top of WM analysis during DASE increases the diagnostic sensitivity to detect obstructive CAD, whatever its definition (≥50% or > 70% stenosis), but it is mainly driven by the sensitivity increase in the intermediate group (50%-70% stenosis).</p> <p>The total diagnostic accuracy increased only when defining CAD as ≥50% stenosis, since in patients with severe stenosis (> 70%) the decrease in specificity is not counterbalanced by the minor sensitivity increase.</p

    Feasibility of real-time three-dimensional stress echocardiography: pharmacological and semi-supine exercise

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    <p>Abstract</p> <p>Background</p> <p>Real time three dimensional (RT3D) echocardiography is an accurate and reproducible method for assessing left ventricular shape and function.</p> <p>Aim</p> <p>assess the feasibility and reproducibility of RT3D stress echocardiography (SE) (exercise and pharmacological) in the evaluation of left ventricular function compared to 2D.</p> <p>Methods and results</p> <p>One hundred eleven patients with known or suspected coronary artery disease underwent 2D and RT3DSE. The agreement in WMSI, EDV, ESV measurements was made off-line.</p> <p>The feasibility of RT-3DSE was 67%. The inter-observer variability for WMSI by RT3D echo was higher during exercise and with suboptimal quality images (good: k = 0.88; bad: k = 0.69); and with high heart rate both for pharmacological (HR < 100 bpm, k = 0.83; HR ≥ 100 bpm, k = 0.49) and exercise SE (HR < 120 bpm, k = 0.88; HR ≥ 120 bpm, k = 0.78). The RT3D reproducibility was high for ESV volumes (0.3 ± 14 ml; CI 95%: -27 to 27 ml; p = n.s.).</p> <p>Conclusions</p> <p>RT3DSE is more vulnerable than 2D due to tachycardia, signal quality, patient decubitus and suboptimal resting image quality, making exercise RT3DSE less attractive than pharmacological stress.</p

    In vitro and in vivo studies of Cucurbita pepo L. flowers: chemical profile and bioactivity

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    Edible flowers consumption has increased in recent years due to their rich content of healthy phytochemicals. The aim of this study was to analyse the chemical profile of Cucurbita pepo L. flowers, and to explore their antioxidant and hypoglycaemic prop- erties. Moreover, in order to assess in vivo effects, biochemical analysis, Reactive Oxygen Metabolites (d-ROMs) and Biological Antioxidant Potential (BAP) tests were performed on mice serum. High Performance Liquid Chromatography-Diode Array Detection (HPLC-DAD) analyses revealed the presence of (þ)-catechin, ()-epicatechin, rutin, and syringic acid as main constituents. 2,20- Azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and Ferric Reducing Antioxidant Power (FRAP) tests showed interest- ing results. The extract exhibited the strongest inhibitory effect on a-glucosidase (IC50 of 144.77lg/mL). In vivo results confirmed the hypoglycaemic effects, also affecting lipid metabolism but did not revealed benefits on ROS production. These results may add some information supporting the use of C. pepo flowers as func- tional foods and/or nutraceuticals

    Effects of systemic glucocorticosteroids on peripheral neutrophil functions in asthmatic subjects: an ex vivo study

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    In 21 asthmatic subjects, several functions of isolated peripheral neutrophils (chemokinesis and chemotaxis toward 10% E. coli; superoxide anion generation after PMA; leukotriene B4 (LTB4) release from whole blood and isolated neutrophtls, before and after different stimuli) were evaluated during an acute exacerbation of asthma, and after 14 – 54 days of treatment with systemic glucocorticosteroids (GCS). During acute exacerbation, superoxide anion generation was higher in asthmatics than in eleven normal subjects (39.2 ± 14.1 vs. 25.2 ± 7.3 nmol, p < 0.05); there was a significant correlation between FEV1 (% of predicted) and neutrophil chemotaxis (r = −0.52, p = 0.04). After treatment, there was no significant change in all neutrophil functions, except for a decrease in neutrophil chemotaxis in subjects who showed an FEV1 increase > 20% after GCS treatment (from 131 ± 18 to 117 ± 21 μm, p = 0.005). Chemokinesis sicantly decreased in all subjects, and the changes significantly correlated with an arbitrary score of the total administered dose of GCS (r = 0.57, p < 0.05). These data suggest that neutrophil activation plays a minor role in asthma, and that treatment with GCS is not able to modify most functions of peripheral neutrophils in asthmatic subjects; chemotaxis seems to be related only to the severity of the asthma and it could reflect the improvement of the disease

    Industrial upcycling of almond skin through production of novel brioches

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    The global sustainability policy emphasizes reusing of agri-food waste and by-products to enhance food bioactive properties. Thus, brioches were processed incorporating almond skin powder (ASP): control (CTR), without ASP addition; 5-ASP, with 5% (w/w) ASP; and 10-ASP, with 10% (w/w) ASP. Seven different brioches shapes were obtained for each recipe. Flavonoids were mainly detected in Tuono almond skin by Ultra-High Performance Liquid Chromatography coupled to High-Resolution Mass Spectrometry (UHPLC-HRMSMS), in particular, flavan-3-ol monomers. The ethanolic extract of Tuono almond skins contained polar lipids (oxylipins and phospholipids). Gas Chromatography–Mass Spectrometry (GC-MS) identified six major fatty acids, mainly oleic acid (48.01%). Photothermal degradation impact on bioactive compounds was evaluated using a first-order kinetic model. Antioxidant activity was studied using 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), 2,2-diphenyl-1-picrylhydrazyl and β-carotene bleaching test. α-amylase, α-glucosidase, and lipase inhibitory effect were also tested. The acidification of the doughs was consistent across all trials. Lactic acid bacteria and yeast levels increased. Importantly, the final products were free from undesirable microorganisms. The addition of ASP led to reduced weight loss and specific volume for all seven brioche types. Furthermore, the firmness, crumb structure, and sensory profile of the final products were noticeably influenced. Tasters clearly favoured the Treccina brioches. The production of sweet leavened baked goods was carried out in triplicate in two independent experiments. The statistical model applied to the data considered the effects of brioche shape and the addition of ASP. Kinetic data revealed that the half-life extension for both total phenol and flavonoid content was observed in the 10-ASP sample (18.00382). 10-ASP sample exhibited promising ABTS radical scavenging activity, with inhibitory concentration 50% (IC50) values of 18.64 mg/mL after 9 days of photothermal degradation. Moreover, when testing 10-ASP Treccina against α-amylase and α-glucosidase, the IC50 values were 198.16 and 190.23 μg/mL, respectively, even after 9 days
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