113 research outputs found
Low-dose CT protocol for orthodontic diagnosis.
No full textAIM: This was to correlate the dosimetric evaluation with high diagnostic
accuracy by suggesting a protocol that significantly reduces the dose
administered by a Dentascan exam without affecting diagnostic accuracy.
MATERIALS AND METHODS: 17 patients were selected consecutively (7 males and 10
females) of a mean age of 11.2 (8-14 years) who sought orthodontic treatment.
They needed CT control before and after treatment with RME to evaluate impacted
canines. The study was performed using a multidetector 16-rows CT with two
protocols that provided 2 different KV acquisition parameters: 80 KV or 120 KV.
Radiation dose was evaluated in two ways: CTDI and DLP. Image quality was rated
and the results were compared to identify significant differences in terms of
image quality, radiation exposure and presence of artefacts.
RESULTS: The 80 KV scanning has a significantly lower effective radiation dose
compared to the 120 KV scanning (p <0.05). The images of all patients were used
for comparing the protocols in terms of image quality. The mean scores for the 80
KV scanning images were 4.18 +/-0.81 and 4.41 +/-0.80 for dose obtained by 120 KV
scanning. The median image quality was 4 (good) for both protocols. The 80 KV
protocol allowed, as well as the 120 KV, a careful analysis by the orthodontist
and the dental surgeon that together, based on this images, can choose the best
line of treatment between several available options.
CONCLUSION: 80 KV protocols compared with 120 KV protocols resulted in reduced
total radiation dose without relevant loss of diagnostic image information and
quality. The images were good enough to obtain information about the exact
position of impacted teeth and to plan the best line of surgical treatment and
mechanotherapy strategy
Control Algorithms and Architectures for Resource Management in Multi-Layered Systems: Application to SatCom, Security and Manufacturing Domains
No full textLast two decades have seen an exponential increase in the availability of innovative and cost effective technological solutions in a wide variety of fields, ranging from electronics to chemistry, from mechanics to computer science. These new potentialities have led to a growth in systems’ complexity, thus making their control and optimization a challenging task, eager for new methodologies, approaches, paradigms. With respect to this context, the doctorate research presented in this thesis aims at providing the scientific and industrial communities with enriched solutions to cope with a specific class of control applications, resource management, in a well-defined class of complex systems, the multi-layered ones.
Multi-layered systems are commonly obtained by incremental design or hierarchical approaches: several layers, each one assigned to a specific task, are put together to jointly create an enriched, vertical or end-to-end, behaviour. In such conditions, resources are necessarily distributed between layers and information sharing is limited, thus resulting in an underutilization of system’s potentialities and poor performances: efficient resource management solutions are needed.
Resource management is in fact the set of mechanism, procedures and algorithms that allow to control the allocation, distribution or utilization of systems’ capabilities (being them hardware or software functionalities, physical or logical resources): for this reason, they play a key role for the overall system’s performances; in recent years, control and optimization theories have proven to be the best candidates to address this class of problems.
This doctorate work provides original results in the following selected multi-layered domains:
- Satellite Communication, with the design of innovative cross-layer algorithms
- Security, with the formalization of the “composable security” by means of control theory
- Manufacturing, with the identification of a closed-loop “cognitive architecture” for the Factories of the Future.
To achieve these results, original research has been performed in the areas of: i) modelling techniques; ii) control algorithms; iii) optimization algorithms.
Some of these results have been jointly developed in the scope of European funded research, in particular in the MONET Project (Satellite Communication) and in the p/nSHIELD Projects (Security in Embedded Systems), where they have represented an original contribution with promising industrial exploitation perspectives.Results have been partially achieved in the scope of the following projects: MONET (FP7), pSHIELD (ARTEMIS-JU), nSHIELD (ARTEMIS-JU
Intertemporal Consumption and the Measurement of Inflation: A Dynamic Inertial Price Index
No full textThis paper develops a new price index (DIPI) and discusses its characteristics and dynamics. By allowing for habit formation and inertia, our model extends typical dynamic indexes that have a forward looking component, thus providing a more effective support for the design of policy measures. We calculate the DIPI for a sample of goods for the US and prove its effectiveness in tracking business cycle, thus resulting in a more reliable indicator for the design of policy measures. Comparison with the official inflation measure matches the results of the Boskin Commission, which argues that CPI overestimates inflation
Kidney transplantation and withdrawal rates among wait-listed first-generation immigrants in Italy
No full textBackground: Multiple barriers diminish access to kidney transplantation (KT) in immigrant compared to non-immigrant populations. It is unknown whether immigration status reduces the likelihood of KT after wait-listing despite universal healthcare coverage with uniform access to transplantation. Methods: We retrospectively collected data of all adult waiting list (WL) registrants in Italy (2010-20) followed for 5 years until death, KT in a foreign center, deceased-donor kidney transplant (DDKT), living-donor kidney transplant (LDKT) or permanent withdrawal from the WL. We calculated adjusted relative probability of DDKT, LDKT and permanent WL withdrawal in different immigrant categories using competing-risks multiple regression models. Results: Patients were European Union (EU)-born (n = 21 624), Eastern European-born (n = 606) and non-European-born (n = 1944). After controlling for age, sex, blood type, dialysis vintage, case-mix and sensitization status, non-European-born patients had lower LDKT rates compared to other immigrant categories: LDKT adjusted relative probability of non-European-born vs. Eastern European-born 0.51 (95% CI: 0.33-0.79; P = 0.002); of non-European-born vs. EU-Born: 0.65 (95% CI: 0.47-0.82; P = 0.001). Immigration status did not affect the rate of DDKT or permanent WL withdrawal. Conclusions: Among EU WL registrants, non-European immigration background is associated with reduced likelihood of LDKT but similar likelihood of DDKT and permanent WL withdrawal. Wherever not available, new national policies should enable coverage of travel and medical fees for living-donor surgery and follow-up for non-resident donors to improve uptake of LDKT in immigrant patients, and provide KT education that is culturally competent, individually tailored and easily understandable for patients and their potential living donors
sj-docx-1-edq-10.1177_08912424221103556 - Supplemental material for A Data-Driven Algorithm to Redefine the U.S. Rural Landscape: Affinity Propagation as a Mixed-Data/Mixed-Method Tool
No full textSupplemental material, sj-docx-1-edq-10.1177_08912424221103556 for A Data-Driven Algorithm to Redefine the U.S. Rural Landscape: Affinity Propagation as a Mixed-Data/Mixed-Method Tool by Benjamin W. Heumann, Marcello Graziano and Maurizio Fiaschetti in Economic Development Quarterly</p
Static and dynamic evaluation of pelvic floor disorders with an open low-field tilting magnet.
No full textAIM:
To assess the feasibility of magnetic resonance defaecography (MRD) in pelvic floor disorders using an open tilting magnet with a 0.25 T static field and to compare the results obtained from the same patient both in supine and orthostatic positions.
MATERIALS AND METHODS:
From May 2010 to November 2011, 49 symptomatic female subjects (mean age 43.5 years) were enrolled. All the patients underwent MRD in the supine and orthostatic positions using three-dimensional (3D) hybrid contrast-enhanced (HYCE) sequences and dynamic gradient echo (GE) T1-weighted sequences. All the patients underwent conventional defaecography (CD) to correlate both results. Two radiologists evaluated the examinations; inter and intra-observer concordance was measured. The results obtained in the two positions were compared between them and with CD.
RESULTS:
The comparison between CD and MRD found statistically significant differences in the evaluation of anterior and posterior rectocoele during defaecation in both positions and of rectal prolapse under the pubo-coccygeal line (PCL) during evacuation, only in the supine position (versus MRD orthostatic: rectal prolapse p < 0.0001; anterior rectocoele p < 0.001; posterior rectocoele p = 0.008; versus CD: rectal prolapse p < 0.0001; anterior rectocoele p < 0.001; posterior rectocoele p = 0.01). The value of intra-observer intra-class correlation coefficient (ICC) ranged from good to excellent; the interobserver ICC from moderate to excellent.
CONCLUSION:
MRD is feasible with an open low-field tilting magnet, and it is more accurate in the orthostatic position than in the supine position to evaluate pelvic floor disorders
Cone beam CT evaluation of skeletal and nasomaxillary complex volume changes after rapid maxillary expansion in OSA children
No full textObjective: The first objective of this study was to evaluate skeletal changes and changes in dimensions and volume of the upper airways before and after rapid maxillary expansion (RME) therapy in children with obstructive sleep apnoea (OSA), by Cone Beam computed tomography (CBCT). The second objective was to evaluate if RME therapy could improve both the patency of the nasal airways and the Obstructive Sleep Apnoea Syndrome (OSAS). Methods: 19 children with OSA and malocclusion took CBCT scans with a Dentascan and 3D reconstruction program before (T0) and 4 months after (T1) RME. Patients underwent an ENT visit with auditory and respiratory tests, including a daytime sleepiness questionnaire, a 19-channel polysomnography, and an orthognatodontic examination before orthodontic therapy (T0), after 2 months (T1) with the device still on, and 4 months after the end of the orthodontic treatment (T2). Results: In all cases opening of the mid-palatal suture was demonstrated. Nasal osseous width, volume of the total upper airways, nasal cavity and nasopharynx and oropharynx increased significantly (P, .001). The increased W-ANS, W-mid and WPNS were closed linked to the enlarged midpalatal suture (P, .001). The increased WPNS were closed linked to the enlarged pterygoid processes (P, .001). The increased V-NC and V-NPA was closely linked to the enlarged W-PNS (P, .001) as well as VOPA and consequently to the enlarged midpalatal suture and pterygoid processes. Conclusion: RME treatment had a positive effect on children affected by chronic snoring and OSA, causing an increase in volume of the nasal cavity and nasopharynx, with expansion of the nasal osseous width and maxillary width. Enlarged nasal width at the PNS plane contributed to the increase in nasopharynx volume. Enlarged maxillary width showed a direct correlation to increased airways volume, bringing a functional improvement. The results show that the RME therapy can restore and improve a normal nasal airflow with disappearance of obstructive sleep breathing disorder. (c) 2021 Elsevier B.V. All rights reserved
Unmasking of an early laser evoked potential by a point localization task
No full textObjectives: The investigation of the CO2 laser evoked potential (LEP) modifications following a point localization task. Methods: LEPs were recorded from 10 healthy subjects in two different conditions. (1) Task condition: laser stimuli were shifted among 3 different locations on the right hand dorsum, and the subjects were asked to identify the stimulated area. The mean error rate in point localization was 4.5%. (2) Non-task condition: laser pulses were delivered on the first intermetacarpal space, and the subject was asked to count the number of stimuli. The mean error rate in counting was 5.8%. Results: In the task condition, the temporal traces contralateral to the stimulation showed an early positive component (eP, mean peak latency 83 ms) preceding the N1 negativity (mean peak latency 144 ms). At the eP peak latency, topographic maps showed a positivity highly focused on the contralateral temporal region. In the non-task recordings no reliable response was identifiable before the N1 potential. Conclusions: While no LEP component earlier than the middle-latency N1 potential can be recorded in the non-task condition, a positive response (eP) preceding the N1 component is identifiable in the contralateral temporal region during the spatial localization of painful stimuli. The eP scalp distribution is compatible with its origin from a radial source in the second somatosensory (or insular) area, thus suggesting that the opercular cortex is involved not only in the middle-latency (N1 potential), but also in early pain processing. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved. <br/
LIVE DONOR KIDNEY TRANSPLANTATION: UPDATING THE OCST SITUATION
No full textLIVE DONOR KIDNEY TRANSPLANTATION: UPDATING THE OCST SITUATIO
- …
