2,135 research outputs found
Aesthetic surgical treatment in anterior maxilla – comparison between lip repositioning versus crown lengthening: literature review
O objetivo deste artigo Ă© abordar o sorriso gengival em uma sĂ©rie de aspectos, incluindo as limitações psicossociais que ele traz ao indivĂduo, os parâmetros de um sorriso estĂ©tico e as etiologias que podem causar a exposição gengival excessiva. O escopo final dependerá de discussões em torno de duas cirurgias minimamente invasivas – Reposicionamento labial e alongamento estĂ©tico da coroa. As Indicações e Contra-indicações de ambas as cirurgias serĂŁo consideradas e comparadas com referĂŞncia Ă quantidade de exposição gengival excessiva que pode ser reduzida desde a consulta inicial atĂ© os acompanhamentos pĂłs-operatĂłrios.
O número de artigos utilizados para a elaboração desta revisão bibliográfica é de 45 artigos, sendo os critérios de exclusão publicações cujo conteúdo não seria relevante para a conclusão do trabalho.The aim of this article is to address the Gummy smile in a number of aspects including the psychosocial limitations it brings to an individual, the parameters of an aesthetic smile, and the aetiologies that can cause the excessive gingival display. The final scope will hinge on discussions surrounding two minimally invasive surgeries - Lip repositions and Aesthetic Crown lengthening. Indications and Contra-indications of both these surgeries will be considered and compared with reference to the amount of Excessive Gingival display that may be reduced from baseline to Post op follow ups.
The number of articles used for the elaboration of this bibliographic review is of 45 articles, with the exclusion criteria being publications whose content would not be relevant for the completion of the work
A feasible and automatic free tool for T1 and ECV mapping
Purpose: Cardiac magnetic resonance (CMR) is a useful non-invasive tool for characterizing tissues and detecting myocardial fibrosis and edema. Estimation of extracellular volume fraction (ECV) using T1 sequences is emerging as an accurate biomarker in cardiac diseases associated with diffuse fibrosis. In
this study, automatic software for T1 and ECV map generation consisting of an executable file was developed and validated using phantom and human data.
Methods: T1 mapping was performed in phantoms and 30 subjects (22 patients and 8 healthy subjects) on a 1.5T MR scanner using the modified Look-Locker inversion-recovery (MOLLI) sequence prototype before and 15 min after contrast agent administration. T1 maps were generated using a Fast Nonlinear
Least Squares algorithm. Myocardial ECV maps were generated using both pre- and post-contrast T1 image registration and automatic extraction of blood relaxation rates.
Results: Using our software, pre- and post-contrast T1 maps were obtained in phantoms and healthy subjects resulting in a robust and reliable quantification as compared to reference software. Coregistration of pre- and post-contrast images improved the quality of ECV maps. Mean ECV value in healthy subjects was
24.5% ± 2.5%.
Conclusions: This study demonstrated that it is possible to obtain accurate T1 maps and informative ECV maps using our software. Pixel-wise ECV maps obtained with this automatic software made it possible to visualize and evaluate the extent and severity of ECV alterations
Fatty images of the heart: spectrum of normal and pathological findings at computed tomography and cardiac magnetic resonance imaging.
Ectopic cardiac fatty images are not rarely detected incidentally at computed tomography and cardiac magnetic resonance, either in exams focused on the heart as in general thoracic imaging evaluations. A correct interpretation of these findings is essential in order to recognize their normal or pathological meaning, focusing on the eventually associated clinical implications. The development of techniques such as computed tomography and cardiac magnetic resonance allowed a detailed detection and evaluation of adipose tissue within the heart. This pictorial review illustrates the most common characteristics of cardiac fatty images at computed tomography and cardiac magnetic resonance, in a spectrum of normal and pathological conditions ranging from physiological adipose images to diseases presenting with cardiac fatty foci. Physiologic intramyocardial adipose tissue may normally be present in healthy adults, being not related to cardiac affections and without any clinical consequence. However cardiac fatty images may also be the expression of various diseases, comprehending arrhythmogenic right ventricular dysplasia, post-myocardial infarction lipomatous metaplasia, dilated cardiomyopathy and lipomatous hypertrophy of the inter-atrial septum. Fatty neoplasms of the heart as lipoma and liposarcoma are also described
Car sharing demand estimation and urban transport demand modelling using stated preference techniques
The research deals with the use of the stated preference technique (SP) and transport demand modelling
to analyse travel mode choice behaviour for commuting urban trips in Palermo, Italy.
The principal aim of the study was the calibration of a demand model to forecast the modal split of the
urban transport demand, allowing for the possibility of using innovative transport systems like car sharing
and car pooling.
In order to estimate the demand model parameters, a specific survey was carried out inside the urban
area of Palermo. The survey focused on the morning rush hour and involved mainly employees, selfemployed
workers and students (about 500 respondents) whose final destination was located within the
historical centre of the city. The questionnaires contained a stated preference experiment regarding the
choice among four different transport alternatives: private car, car pooling, car sharing and public
transport.
A random utility model was developed by using data resulting from the SP experiment. We found out
that, for the specific case of Palermo, the multinomial logit proved to be the best urban transport demand
model, even if the choice set contained three car alternatives. We identified as main attributes affecting
mode choice behaviour the one-way trip travel time and cost, the parking time, the number of cars
available to each household member, the alternative specific attributes for the car option and the car
sharing one.
The model was applied to analyse the potential demand for car sharing and car pooling in Palermo,
under a future scenario characterized by several policy actions for limiting private transport use. The
analysis highlighted that the car club market share could increase up to the 10% level, while car pooling
could slightly rise
MR imaging of tenosynovial giant cell tumor: additional value of a T2*-weighted gradient echo sequence
Title:
MR imaging of tenosynovial giant cell tumor: additional value of a T2*-weighted gradient echo sequence
Background/Purpose:
To evaluate the role of a T2*-weighted gradient echo (GRE) sequence added to a standard MR imaging protocol in assessing the iron content of tumor tissue and the extent of joint involvement in patients with tenosynovial giant cell tumor (TGCT).
Methods and Materials:
MR studies of 58 patients (mean age: 36,7 years; 35 female, 23 male) with histologically proven TGCT (knee: n=44, hip: n=5, ankle: n=5, elbow: n=1, tarsus: n=1, tendon sheath: n=2) obtained prior to surgical resection were retrospectively analyzed. All examinations were performed according to a standardized protocol which in addition to T1-, T2-weighted and CE SE/TSE sequence a T2*-weighted GRE sequence is included. Standard and GRE images were separately analyzed by three independent observers with regard to 1) relative iron content of tumor tissue as determined by the distribution and extent of blooming (susceptibility) artifacts (0-absent, 1-focal (70%)) and 2) the identification of tumor tissue on GRE images in joint compartments which appeared uninvolved on images of standard sequences. Intraoperative and histologic findings served as the standards of reference. All histologic specimens were reviewed and iron content was graded corresponding to the above mentioned classification by an experienced pathologist.
Results:
59% of the lesions were classified (WHO 2013) as localized and 41% as diffuse TGCTs. On histologic review, the iron content was graded as follows: 0: n=2, 1: n=13, 2: n=29, 3: n=14. The diagnostic accuracy of GRE images in assessing the iron content of tumor tissue accordingly was 88%, 79% and 81% with K values of 0.812, 0.683 and 0.715 for observer 1, 2, and 3 respectively. Interobserver agreement was excellent with kappa values ranging from 0.843 to 0.905. Overall, iron deposits were depicted on histopathology in 96.5% and on MR images in 93-96,5% of TGCTs. On GRE images the observers diagnosed involvement of joint compartments not seen on standard images alone in 6/58 (10%), 6/58 (10%), and 5/58 (8%) of cases.
Conclusions:
A T2*-weighted GRE sequence added to a standard MR protocol allows accurate and reproducible quantification of iron content in TGCTs. Due to the high incidence of iron deposits in these synovial lesions, this ability together with typical MR findings on T1 and T2 weighted images might be of help to establish the diagnosis more confidently. Furthermore, GRE images depict tumor manifestations in joint compartments that can appear uninvolved on standard images and thus, are helpful in planning of surgical treatment
A demand-based methodology for planning the bus network of a small or medium town
This work aims at developing a demand-based methodology for designing the bus network of a small
or medium town. The proposed modelling tool adopts a multi-agent objective function which evaluates
performance in the context of different stakeholders: the surplus of travellers (car and bus users); the bus
service provider’s revenues and operation costs. This approach was applied to an existing bus network,
serving Trapani, which is a medium town in the south of Italy (Sicily), with 100000 inhabitants. The busbased
public transport system attracts only about 5% of commuter trips within Trapani (source: National
Institute of Statistics, 2005). This paper reports on an analysis of the application of the proposed multiagent
modelling tool to two planning scenarios: the first is short-term and characterized by a budget
constraint (slight changes in the availability of drivers and vehicles) and the second long-term with new
investments in new buses to improve services and increase patronage. In both cases, the impact of the
recent car park charging policy launched by the local administration was considered.
The decision variables for the optimisation procedure were route, service frequency and capacity of
each bus line. A random utility model was employed to forecast the mode choices for trips within Trapani
and the travel demand-supply equilibrium was obtained using the DUE (deterministic user equilibrium)
assignment algorithm, for private transport, and the hyperpath network loading algorithm, for public
transport.
The optimisation procedure led to a more efficient bus network characterized by increase in bus
frequencies and a better performance in terms of reduced travel time, especially for trips bound for the
“old town” in the morning. In addition, a higher number of origin-destination pairs were served, at the
expense of the need to interchange between the inner more frequent and the outer less frequent services.
This implied that the number of transfers from one bus line to another significantly increased
The analysis of urban travellers' latent preferences to explain their mode choice behaviour.
Our research aims to explore the impact of latent variables, mirroring urban travellers’ attitudes and perceptions, on the individual decision making process
regarding the mode of transport. The paper describes the first results of an ongoing research activity, which derive from a pilot study conducted in Palermo,
the capital of the Sicilian Region (in the south of Italy), and demonstrate that policy makers, in designing a socially desirable and environmentally sustainable
urban mobility system, should take into account how travellers perceive the qualitative dimensions of transport
Building monitoring system in a large social housing intervention in Northern Italy
Within the framework of the well-known problem of the performance gap, the paper demonstrates how a building monitoring system is able to provide feedback data instrumental to address the ongoing management issues of multi-family buildings in social housing: the need to have a good understanding of what works and what does not in building operation, the need of bills controlling and allocation of individual costs between the occupants, the facility and energy management requirements including the understanding of occupant’s behavior. It adopts a case study approach, discussing the case of a large environmentally friendly social housing intervention consisting in 323 flats, in which a building monitoring system was installed
Standardization of Road Danger Signs in the European Union
The aim of this research is to find a solution for the standardization of road signs in the EU zone by a comparative analysis of different national sign systems to establish a common set from a single country. This work is based on the idea that road sign standardization might increase the safety level of transnational journeys and foster the relationships among the various members of the EU Community. This paper presents the outcome of the first step of the research, which focuses on the harmonization of danger signs. In more detail, a multicriteria approach is applied to rank 19 EU Member States on the basis of three main aspects: the installation cost of new signs, new sign learning issues and the effectiveness of sign systems. The study allows for the installation cost by quantifying the degree of similarity among road sign systems and the roadway network extension, on which new signs should be placed.</span
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