1,721,133 research outputs found
Reader response: Increased resting cerebral blood flow in adult Fabry disease: MRI arterial spin labeling study
No full textAuthor response: Alterations of functional connectivity of the motor cortex in Fabry disease: An RS-fMRI study
No full text
Encefalo (in "Diagnostica per Immagini", Autori Vari)
No full textPrincipali campi di applicazione delle tecniche di diagnostica per immagini nelle malattie dell'encefal
Impact of unrealistic worst case modeling on the performance of VLSI circuits in deep submicron CMOS technologies
No full textThe impact of process fluctuations on the variability
of deep submicron (DSM) very large scale integration (VLSI)
circuit performances is investigated in this paper. In particular,
we show that as process dimensions scale down in the subhalfmicron
region, the relative weight of process variability tends
to increase, thus wearing down a non negligible portion of the
benefits that are expected from minimum feature size scaling. We
will show that in order to better exploit the advance of process
technology, it is essential to adopt a realistic approach to worst
case modeling, as the one described in [1] [assigned probability
technique (APT)]. The application of the APT technique to
different test circuits designed in 0.35, 0.25, and 0.18 m CMOS
technologies with a power supply ranging from 3.3 V down to 1
V will demonstrate how the manufacturability of DSM designs
is going to be a vital factor for the successful implementation of
high-performance or low-power systems in 0.18 m and lesser
technologies
Endovascular treatment of chronic hemoptysis in patients with pulmonary tuberculosis
No full textBackground: We aimed to demonstrate the safety and efficacy of bronchial artery embolization (BAE) in patients with pulmonary tuberculosis in the planned management of “mild” hemoptysis. This treat-ment, already widely documented and used as a life-saving therapy in an emergency regimen, if properly planned in poorly controlled patients through medical therapy alone, can provide a valid opportunity by reducing the frequency and extent of non-fatal bleeding, but which still worsen the quality of life of these already significantly traumatized patients. Methods: All procedures were conducted through a right common femoral access with a 5 Fr catheter and a 2.7 Fr super-selective catheter coaxial technique of the branches of the bronchial arteries with suspected bleeding sources. Embolizations were performed with 500-700 micron Terumo PVA plastic microparticles. We decided to adopt the following inclusion criteria for the selection of patients to be enrolled: documented diagnosis of pulmonary TB, the presence of at least one bleeding epi-sode that required at least two blood transfusions, evaluation with bronchoscopic examination to ascertain the bronchial origin of bleeding and the affected lobar site, execution of an angio-ct radiological study for the evaluation of the bronchial systemic anatomy as well as the patency of the pulmonary arterial circulation, general hemodynamic compensation and an age of enrollment between 25 and 65 years. Results: All selective embolization interventions demonstrated a technical success of 100% of the total number of patients. 11 out of 12 patients did not show any signs of relapse or complications related to the interventional procedure at a first check-up carried out at 48 hours, instead a fatal massive hemoptysis occurred in only one patient. At the next three-month follow-up, no relapses were documented in all selected patients. Only one patient required a second embolization four months after the first procedure. Conclusions: Radiological-interventional approach in the elective regimen of super-selective embolization of the bronchial arteries (BAE) in the management and control of “mild” hemoptysis in patients with pulmonary tuberculosis not controlled exclusively by medical therapy, according to a strategy systematic of planned intervention and respecting clear and standardized inclusion criteria, represented in our experience a safe and effective procedure, free from significant short and long term complications, especially in well selected patients, which, although not always allows a definitive and stable control of hemoptysis, can in any case significantly limit the risks, also allowing a better planning of the most appropriate therapeutic intervention strategy
Analysis of the impact of intra-die variance on clock-skew
No full textIn this work, we analyze the impact of local process variations on the clock skew of VLSI circuits designed in deep sub-micron technologies. As the size of active repeaters decreases, the utilization of dense buffering schemes, up to complete replacement of metal wiring with active devices, has been proposed in order to realize efficient and noise-immune clock distribution networks. However, local variance of MOSFET electrical parameters, such as VT and IDSS, increases with scaling of device dimensions, thus causing large intra-die variability of the timing properties of clock buffers. As a consequence, we expect local mismatch to be a significant source of clock skew in deep sub-micron technologies. In order to accurately verify this assumption, we applied advanced statistical simulation techniques and accurate mismatch characterization data to the statistical simulation of relatively small clock distribution networks. The comparison with Monte Carlo simulations performed by neglecting the mismatch effect confirmed that it is necessary to account for local device variations in the design and sizing of the clock distribution network
Dorsolateral prefrontal cortex volume in patients with deficit or nondeficit schizophrenia
No full textDeficit schizophrenia (DS) represents a promising putative clinical subtype of schizophrenia and is characterized by the presence of primary and enduring negative symptoms. Previous studies have often reported a reduced amount of gray matter within prefrontal and temporal cortices in schizophrenia subjects with prevailing negative symptoms; however, the evidence concerning brain structural abnormalities in patients with DS remains controversial. The aim of the present study was to investigate whether patients with DS differed from those with nondeficit schizophrenia (NDS) with respect to the volume of the dorsolateral prefrontal cortex (DLPFC) and hippocampus, two brain areas considered as key regions in the pathogenesis of schizophrenia. In the present study a 3D-T1w MR imaging procedure and an extensive clinical assessment was carried out in 18 patients with schizophrenia, (10 DS and 8 NDS). 3D MPRAGE images were preprocessed with SPM software and two regions of interest (hippocampus and DLPFC) were manually traced to obtain their gray matter volumes. We found a significant reduction of DLPFC in the entire schizophrenia group, with respect to healthy subjects. Although the subgroup of patients with DS had a more severe clinical picture and more impaired social functioning, the DLPFC volume reduction was greater in NDS than in DS patients. In conclusion, according to our structural neuroimaging findings, DS patients, although characterized by a more severe clinical picture and a worse outcome, show less neurobiological abnormalities. (C) 2012 Elsevier Inc. All rights reserved
Dorsolateral prefrontal cortex volume in patients with deficit or nondeficit schizophrenia
No full textDeficit schizophrenia (DS) represents a promising putative clinical subtype of schizophrenia and is characterized by the presence of primary and enduring negative symptoms. Previous studies have often reported a reduced amount of gray matter within prefrontal and temporal cortices in schizophrenia subjects with prevailing negative symptoms; however, the evidence concerning brain structural abnormalities in patients with DS remains controversial. The aim of the present study was to investigate whether patients with DS differed from those with nondeficit schizophrenia (NDS) with respect to the volume of the dorsolateral prefrontal cortex (DLPFC) and hippocampus, two brain areas considered as key regions in the pathogenesis of schizophrenia. In the present study a 3D-T1w MR imaging procedure and an extensive clinical assessment was carried out in 18 patients with schizophrenia, (10 DS and 8 NDS). 3D MPRAGE images were preprocessed with SPM software and two regions of interest (hippocampus and DLPFC) were manually traced to obtain their gray matter volumes. We found a significant reduction of DLPFC in the entire schizophrenia group, with respect to healthy subjects. Although the subgroup of patients with DS had a more severe clinical picture and more impaired social functioning, the DLPFC volume reduction was greater in NDS than in DS patients. In conclusion, according to our structural neuroimaging findings, DS patients, although characterized by a more severe clinical picture and a worse outcome, show less neurobiological abnormalities. (C) 2012 Elsevier Inc. All rights reserved
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