3,503 research outputs found
Metodologie per l’individuazione dei settori high-tech. Il caso della Toscana
Il presente lavoro, oltre a fornire una rassegna della letteratura scientifica sull’importanza della dimensione territoriale nell’analisi dei settori ad alta tecnologia, affronta una serie di possibili criteri di misurazione di tali fenomeni in base alla concentrazione territoriale delle imprese. Si pone infatti spesso in questo ambito l’esigenza di trovare il giusto equilibrio tra la scelta di cogliere le dimensioni il più possibile “reali” del settore e quella di disporre di statistiche ufficiali su di esso. Per queste ultime, un vincolo molto importante è rappresentato dal trade off tra l’obiettivo di garantire la confrontabilità e la integrabilità di dati di fonti diverse e la possibilità di un’“aderenza reale” delle informazioni alle caratteristiche dell’universo oggetto di indagine. A partire da valutazioni su uno dei settori ad alta tecnologia a maggiore diffusione nell’unità territoriale scelta (la Toscana), che è il comparto delle Information and Communication Technologies, viene qui presentata una metodologia che tende a soddisfare la necessità di ricorrere a fonti ufficiali, più complete e confrontabili, procedendo ad una “riclassificazione” degli archivi amministrativi, e conduce a risultati parzialmente indipendenti dall’attribuzione del codice ATECO e più aderenti alla reale attività svolta dalle imprese stesse. I risultati ottenuti per il territorio della Toscana, e almeno in parte validati da una indagine field sulle imprese appartenenti ai livelli più elevati di qualificazione evidenziano la possibile stratificazione prodotta dal criterio di selezione e la sua aderenza ad altre forme “empiriche” di indagine, tra cui quella dell’Osservatorio sulle imprese high-tech della Toscana.
Thrombosis Is Reduced by Inhibition of COX-1, but Unaffected by Inhibition of COX-2, in an Acute Model of Platelet Activation in the Mouse
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Do selective cyclo-oxygenase-2 inhibitors and traditional non-steroidal anti-inflammatory drugs increase the risk of atherothrombosis? Meta-analysis of randomised trials
Objective: To assess the effects of selective cyclo-oxygenase-2 (COX 2) inhibitors and traditional non-steroidal anti-inflammatory drugs (NSAIDs) on the risk of vascular events. Design: Meta-analysis of published and unpublished tabular data from randomised trials, with indirect estimation of the effects of traditional NSAIDs. Data sources: Medline and Embase (January 1966 to April 2005); Food and Drug Administration records; and data on file from Novartis, Pfizer, and Merck. Review methods: Eligible studies were randomised trials that included a comparison of a selective COX 2 inhibitor versus placebo or a selective COX 2 inhibitor versus a traditional NSAID, of at least four weeks' duration, with information on serious vascular events (defined as myocardial infarction, stroke, or vascular death). Individual investigators and manufacturers provided information on the number of patients randomised, numbers of vascular events, and the person time of follow-up for each randomised group. Results: In placebo comparisons, allocation to a selective COX 2 inhibitor was associated with a 42% relative increase in the incidence of serious vascular events (1.2%/year v 0.9%/year; rate ratio 1.42, 95% confidence interval 1.13 to 1.78; P = 0.003), with no significant heterogeneity among the different selective COX 2 inhibitors. This was chiefly attributable to an increased risk of myocardial infarction (0.6%/year v 0.3%/year; 1.86, 1.33 to 2.59; P = 0.0003), with little apparent difference in other vascular outcomes. Among trials of at least one year's duration (mean 2.7 years), the rate ratio for vascular events was 1.45 (1.12 to 1.89; P = 0.005). Overall, the incidence of serious vascular events was similar between a selective COX 2 inhibitor and any traditional NSAID (1.0%/year v 0.9/%year; 1.16, 0.97 to 1.38; P = 0.1). However, statistical heterogeneity (P = 0.001) was found between trials of a selective COX 2 inhibitor versus naproxen (1.57, 1.21 to 2.03) and of a selective COX 2 inhibitor versus non-naproxen NSAIDs (0.88, 0.69 to 1.12). The summary rate ratio for vascular events, compared with placebo, was 0.92 (0.67 to 1.26) for naproxen, 1.51 (0.96 to 2.37) for ibuprofen, and 1.63 (1.12 to 2.37) for diclofenac. Conclusions: Selective COX 2 inhibitors are associated with a moderate increase in the risk of vascular events, as are high dose regimens of ibuprofen and diclofenac, but high dose naproxen is not associated with such an excess
Platelet activation and lipid peroxidation in patients with acute ischemic stroke
BACKGROUND AND PURPOSE: Both platelet activation and lipid peroxidation are potential sources of vasoactive eicosanoids that can be produced via the cyclooxygenase pathway, ie, thromboxane (TX) A2, or by free radical-catalyzed peroxidation of arachidonic acid, ie, isoprostanes. We investigated the biosynthesis of TXA2 and F2-isoprostanes, as reflected by the urinary excretion of 11-dehydro-TXB2 and 8-epi-prostaglandin (PG) F2 alpha respectively, in 62 consecutive patients (30 men, 32 women; mean age, 67 +/- 14 years) with acute ischemic stroke.
METHODS: At least two consecutive 6-hour urine samples were obtained during the first 72 hours after onset of symptoms. Urinary eicosanoids were measured by previously described radioimmunoassays.
RESULTS: Repeated periods of enhanced thromboxane biosynthesis were found in 52% of patients. Urinary 11-dehydro-TXB2 averaged 221 +/- 207 (mean +/- SD; n = 197; range, 13 to 967) pmol/mmol creatinine in 30 patients treated with cyclooxygenase inhibitors (mostly aspirin) at the time of study versus 392 +/- 392 (n = 186; range, 26 to 2533) in 32 untreated patients (P .05). The correlation between the two metabolites was moderate in both untreated patients (r = .41, P < .001) and patients with cyclooxygenase inhibitors (r = .31, P < .001). In a multiple regression analysis, increased thromboxane production was independently associated with severity of stroke on admission, atrial fibrillation, and treatment with cyclooxygenase-inhibiting drugs.
CONCLUSIONS: We conclude that during the first few days after an acute ischemic stroke (1) platelet activation occurs repeatedly in a cyclooxygenase-dependent fashion; (2) platelet activation is not associated with concurrent changes in isoprostane biosynthesis; (3) platelet activation is independently associated with stroke severity and atrial fibrillation; and (4) isoprostane biosynthesis is largely independent of platelet cyclooxygenase activity
COIN: Opening the internet of things to people's mobile devices
People's interaction with IoT devices such as proximity beacons, body-worn sensors, and controllable light bulbs is often mediated through personal mobile devices. Current approaches usually make applications operate in separate silos, as the functionality of IoT devices is fixed by vendors and typically accessed only through low-level proprietary APIs. This limits the flexibility in designing applications and requires intense wireless interactions, which may impact energy consumption. COIN is a system architecture that breaks this separation by allowing developers to flexibly run a slice of a mobile app's logic onto IoT devices. Mobile apps can dynamically deploy arbitrary tasks implemented as loosely coupled components. The underlying runtime support takes care of the coordination across tasks and of their real-time scheduling. Our prototype indicates that COIN both enables increased flexibility and improves energy efficiency at the IoT device, compared to traditional architectures
GIS based Integration and Analysis of multiple source Information for Non-Proliferation Studies
In recent years the volume and variety of information that needs to be analysed in the context of non-proliferation have been increasing continuously Therefore, an integrated, all-source information analysis is paramount for an efficient and effective monitoring of the Non-Proliferation Treaty (NPT). The ¿Treaty Monitoring¿ workpackage of the LIMES research project addressed this issue by developing an integrated platform supporting the non-proliferation image analyst in verifying treaty compliance. The main benefits of the platform are (i) integrating information from multiple sources and time-frames, including satellite imagery, site models, open source information, reports, etc; (ii) improved information management using a GIS-based platform and (iii) enhanced methodologies for satellite image analysis. The platform components facilitate the analysis by highlighting changes and anomalies, which are potentially safeguards-relevant and by providing quantitative measurements which are not readily available from the images. It improves the efficiency and effectiveness of the information assessment by providing all-source integration capabilities, which allow to easily access supporting collateral information (e.g. Open Source information) from an image analysis task, an vice versa. The paper presents the components of the integration platform and the results of the demonstration which monitored the construction of a nuclear reactor in Olkiluoto, Finland.JRC.E.9-Nuclear security (Ispra
Increased thromboxane biosynthesis is associated with poststroke dementia
BACKGROUND AND PURPOSE: It has been suggested that daily intake of aspirin
is associated with a reduction of cognitive decline, both in normal and in
demented subjects, but the mechanism is unclear. We have therefore studied
the relationship between thromboxane (TX) A(2) biosynthesis, as reflected
by the urinary excretion of 11-dehydro-TXB(2), and the presence of
dementia in patients after acute stroke. METHODS: Patients from the
Rotterdam Stroke Databank were screened for dementia between 3 and 9
months after stroke. Patients had a full neurological examination,
neuropsychological screening, and, if indicated, extensive
neuropsychological examination. Criteria used for the diagnosis of
dementia were from the Diagnostic and Statistical Manual of Mental
Disorders, Third Edition (Revised). Urine samples were taken at the time
of screening. Urinary 11-dehydro-TXB(2) was measured by means of a
previously validated radioimmunoassay. RESULTS: Dementia was diagnosed in
71 patients, and urine samples were available for 62. Median value (range)
of 11-dehydro-TXB(2) was 399 (89 to 2105) pmol/mmol creatinine for
demented patients versus 273 (80 to 1957) for 69 controls with stroke but
without dementia (P=0.013). No difference was found between 44 patients
with vascular dementia, 404 (89 to 2105) pmol/mmol creatinine, and 18
patients with Alzheimer's disease plus cerebrovascular disease, 399 (96 to
1467) pmol/mmol creatinine (P=0.68). In a stepwise logistic regression
analysis, in which possible confounders such as use of antiplatelet
medication, cardiovascular risk factors, and type of stroke were taken
into account, increased urinary excretion of 11-dehydro-TXB(2) remained
independently related to the presence of dementia (OR 1.12, 95% CI 1.03 to
1.22 per 100 pmol/mmol creatinine). The difference in metabolite excretion
rates between demented and nondemented patients was most prominent within
the subgroup of ischemic stroke patients who received aspirin (P<0.01).
CONCLUSIONS: Increased thromboxane biosynthesis in the chronic phase after
stroke is associated with the presence of but not the type of poststroke
dementia. It is particularly apparent in patients on aspirin, thereby
suggesting the involvement of extraplatelet sources of TXA(2) production
in this setting
Potentiation of thrombus instability: a contributory mechanism to the effectiveness of antithrombotic medications
© The Author(s) 2018The stability of an arterial thrombus, determined by its structure and ability to resist endogenous fibrinolysis, is a major determinant of the extent of infarction that results from coronary or cerebrovascular thrombosis. There is ample evidence from both laboratory and clinical studies to suggest that in addition to inhibiting platelet aggregation, antithrombotic medications have shear-dependent effects, potentiating thrombus fragility and/or enhancing endogenous fibrinolysis. Such shear-dependent effects, potentiating the fragility of the growing thrombus and/or enhancing endogenous thrombolytic activity, likely contribute to the clinical effectiveness of such medications. It is not clear how much these effects relate to the measured inhibition of platelet aggregation in response to specific agonists. These effects are observable only with techniques that subject the growing thrombus to arterial flow and shear conditions. The effects of antithrombotic medications on thrombus stability and ways of assessing this are reviewed herein, and it is proposed that thrombus stability could become a new target for pharmacological intervention.Peer reviewedFinal Published versio
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