293 research outputs found
Are matrix metalloproteinases the missing link?
none3openMANNELLO F; TONTI G.A.; PAPA SMannello, Ferdinando; Tonti, GAETANA ANNA MARIA; Papa, Stefan
Linear dichroism of CdSe nanodots: Large anisotropy of the band-gap absorption induced by ground-state dipole moments
We measured the electric field induced linear dichroism for a wide range of sizes of CdSe nanocrystals. Large ground-state dipole moments were observed, especially for the smallest crystals. In these, we found a very large anisotropy of the absorption and most of the dipole strength is along the direction of the ground-state dipole moment. For the anisotropy, we propose a mechanism for intensity borrowing from intraband transitions, induced by the field of the ground-state dipole moment. © 2008 The American Physical Society
DNA quantification to assess Zymoseptoria tritici on a susceptible cultivar of durum wheat to establish the best timing for fungicide application in an italian environment
Zymoseptoria tritici, a globally distributed pathogen, is responsible of Septoria tritici blotch (STB), one of the most damaging wheat diseases. In Italy the incidence of STB has increased during the past few years. The presence of Z. tritici on flag leaves of susceptible durum wheat plants, cultivar San Carlo, after a single artificial inoculation with two inoculum concentrations at different vegetative stages has been evaluated in the plain of Bologna (North of Italy), in a two year field study (2012â2013). The pathogen presence was also assessed in natural infection conditions after a fungicide application in the second year (2013). The results obtained, by visual examination (Incidence, Disease Severity) and DNA quantification by Real time PCR, demonstrated that BBCH 39 (flag leaf stage) is the most susceptible vegetative stage, independently of inoculum concentration and climatic conditions. A good correlation between Disease Severity and DNA quantity was observed in either sampling methods, entire flag leaves and flag leaf discs. Thereafter the most suitable period to obtain the best crop protection with only one fungicide treatment is the flag leaf stage
Semantic-based policy engineering for autonomic systems
This paper presents some important directions in the use of ontology-based semantics in achieving the vision of Autonomic Communications. We examine the requirements of Autonomic Communication with a focus on the demanding needs of ubiquitous computing environments, with an emphasis on the requirements shared with Autonomic Computing. We observe that ontologies provide a strong mechanism for addressing the heterogeneity in user task requirements, managed resources, services and context. We then present two complimentary approaches that exploit ontology-based knowledge in support of autonomic communications: service-oriented models for policy engineering and dynamic semantic queries using content-based networks. The paper concludes with a discussion of the major research challenges such approaches raise
Combined flow-based imaging assessment of optimal cardiac resynchronization therapy pacing vector: A case report
Background: There are still many pendent issues about the effective evaluation of cardiac resynchronization
therapy impact on functional mitral regurgitation. In order to reduce the intrinsic difficulties of quantification of
functional mitral regurgitation itself, an automatic quantification of real-time three-dimensional full-volume color
Doppler transthoracic echocardiography was proposed as a new, rapid, and accurate method for the assessment of
functional mitral regurgitation severity. Recent studies suggested that images of left ventricle flow by echo-particle
imaging velocimetry could be a useful marker of synchrony. Echo-particle imaging velocimetry has shown that
regional anomalies of synchrony/synergy of the left ventricle are related to the alteration, reduction, or suppression
of the physiological intracavitary pressure gradients.
Case summary: We describe a case in which the two technologies are used in combination during acute
echocardiographic optimization of left pacing vector in a 63-year-old man, Caucasian, who showed worsening heart
failure symptoms a few days after an implant, and the effect of the device\u2019s optimization at 6-month follow-up.
Discussion: The degree of realignment of hemodynamic forces, with quantitative analysis of the orientation of blood
flow momentum (\u3c6), can represent improvement of fluid dynamics synchrony of the left ventricle, and explain, with a
new deterministic parameter, the effects of cardiac resynchronization therapy on functional mitral regurgitation. Realtime three-dimensional color flow Doppler quantification is feasible and accurate for measurement of mitral inflow, left
ventricular outflow stroke volumes, and functional mitral regurgitation severity.
Conclusion: This clinical case offers an innovative and accurate approach for acute echocardiographic optimization of
left pacing vector. It shows clinical utility of combined three-dimensional full-volume color Doppler transthoracic
echocardiography/echo-particle imaging velocimetry assessment to increase response to cardiac resynchronization
therapy, in terms of reduction of functional mitral regurgitation, improving fluid dynamics synchrony of the left
ventricle
Intraventricular flow patterns during right ventricular apical pacing
Objectives To assess differences in blood flow
momentum (BFM) and kinetic energy (KE) dissipation in
a model of cardiac dyssynchrony induced by electrical
right ventricular apical (RVA) stimulation compared with
spontaneous sinus rhythm.
Methods We cross-sectionally enrolled 12 consecutive
patients (mean age 74\ub18 years, 60% male, mean left
ventricular ejection fraction 58%\ub16 %), within 48 hours
from pacemaker (PMK) implantation. Inclusion criteria
were: age>18 years, no PMK-dependency, sinus rhythm
with a spontaneous narrow QRS at the ECG, preserved
ejection fraction (>50%) and a low percentage of PMKstimulation (<20%). All the participants underwent a
complete echocardiographic evaluation, including left
ventricular strain analysis and particle image velocimetry.
Results Compared with sinus rhythm, BFM shifted from
27\ub13.3 to 34\ub17.6\ub0 (p=0.016), while RVA-pacing was
characterised by a 35% of increment in KE dissipation,
during diastole (p=0.043) and 32% during systole
(p=0.016). In the same conditions, left ventricle global
longitudinal strain (LV GLS) significantly decreased from
17\ub13.3 to 11%\ub12.8% (p=0.004) during RVA-stimulation.
At the multivariable analysis, BFM and diastolic KE
dissipation were significantly associated with LV GLS
deterioration (Beta Coeff.=0.54, 95% CI 0.07 to 1.00,
p=0.034 and Beta Coeff.=0.29, 95% CI 0.02 to 0.57,
p=0.049, respectively).
Conclusions In RVA-stimulation, BFM impairment and
KE dissipation were found to be significantly associated
with LV GLS deterioration, when controlling for potential
confounders. Such changes may favour the onset of
cardiac remodelling and sustain heart failure
Strategie temporanee post-disastro nei territori fragili italiani
La sessione speciale si inscrive nell'ambito delle iniziative proposte dalla rete di giovani ricercatori "TEMP Una rete interdisciplinare e interuniversitaria che si propone di indagare, mediante un confronto ampio e molteplice, il tema della temporaneitaÌ post-emergenza nel territori fragili italiani nella sua complessitaÌ e multidimensionalitaÌ. Dunque, specifica attenzione eÌ rivolta al contesto italiano e tra le varie emergenze che connotano questi territori, si fa riferimento alle conseguenze determinate dal frequenti fenomeni sismici, eventi che hanno la forza di sovvertire dinamiche spaziali e territoriali consolidate. L'immediata risposta emergenziale allevento apre ad un intervallo temporale che concentra forze pubbliche, economiche e socio- culturali responsabili di nuove gerarchie di necessitaÌ, nuovi assetti territoriali e geografie instabili In questo contesto, il consolidato approccio settoriale all'emergenza -prima emergenza, secondo emergenza e ricostruzione-si dimostra sempre piuÌ inadatto a fronteggiare la complessitaÌ dell'attuale policrisi che vede inedite e molteplici interrelazioni e concatenazioni tra differenti rischi, catastrofi ed emergenze. CioÌ richiede continue azioni elastiche e preventive di pianificazione strategica che possano guidare la trasformazione nel lungo periodo
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