575 research outputs found
Limb reconstruction with knee mega-prosthesis in patients with distal femur primary tumours: gait analysis and alignment evaluation
Introduction: The aim of this study was the functional evaluation and lower limb alignment assessment of patients with a modular knee prosthesis after distal femur resection for primary bone tumour. Materials and methods: 15 patients affected by distal femur tumor and treated with a megaprosthesis implant (6 females and 9 males, mean age: 41 years, range: 15-74 years) and 15 controls were recruited for the study. For each subject the function evaluation included an instrumented gait analysis, while only patients underwent a teleradiography and a latero-lateral X-ray projection of the knee. Results: The duration of the stance phase of gait was shortened in the prosthetic limb with respect to the contralateral limb (57.5±3.6 % gait cycle vs. 60.9±4.8 % gait cycle, P = 0.01), with a correspondent increase of the swing phase. The prosthetic limb also showed an altered knee joint kinematic curve during gait, with a flexion deficit at load response with respect to the contralateral limb (4.5±3.6° vs. 13.4±5.0°, P = 0.000003). Abnormal timing in the muscle activation intervals were observed for tibialis anterior, gastrocnemius lateralis and rectus femoris of the prosthetic limb. The prosthetic limb was found to be misaligned with respect to the contralateral limb, both for the femorotibial (P<0.05) and the ankle joints (P<0.05). Conclusions: Gait analysis performed widely in reference centres could lead to a change in the design of megaprostheses to improve the function and prevent degenerative changes in not involved joint. A multicentric expertise is mandator
Sky Quality Meter and satellite correlation for night cloud-cover analysis at astronomical sites
The analysis of night cloud cover is very important for astronomical observations in real time, considering a typical observation time of about 15 minutes, and to provide statistics. In this article, we use the Sky Quality Meter (SQM) for high-resolution temporal analysis of the La Silla and Asiago (Ekar Observatory) sky: 3 and 5 minutes respectively. We investigate the annual temporal evolution of the natural contributions of the sky at a site not influenced by artificial light at night (ALAN) and at one highly influenced. We also make a correlation between GOES and Aqua satellite data and ground-based SQM data to confirm the relationship between the SQM data and cloud cover. We develop an algorithm that allows the use of the SQM for night cloud detection and reach correlations with the nighttime cloud cover detected by the GOES and Aqua satellites of 97.2 per cent at La Silla and 94.6 per cent at Asiago. Our algorithm also classifies photometric (PN) and spectroscopic nights (SN). We measure 59.1 per cent PN and 21.7 per cent SN for a total percentage of clear nights of 80.8 per cent at La Silla in 2018. The respective Ekar Observatory values are 31.1 per cent PN, 24.0 per cent SN and 55.1 per cent of total clear night time. Application to the SQM network would involve the development of long-term statistics and large data forecasting models for site testing and real-time astronomical observation
New basic insights on the potential of chitosan-based medical device for improving functional recovery after radical prostatectomy
Long-term functional evaluation of the treated kidney in a prospective series of patients who underwent laparoscopic partial nephrectomy for small renal tumors.
Background: Renal scintigraphy may allow long-term monitoring of ischemic damage after partial nephrectomy (PN). Objective: Evaluate use of renal scintigraphy for evaluating long-term effects of warm ischemia on renal function in patients with a normal contralateral kidney. Design, setting, and participants: We prospectively examined kidney function of 54 patients who underwent laparoscopic PN (LPN). Minimum follow-up time was 4 yr. Intervention: LPN was performed with warm ischemia by transperitoneal or retroperitoneal approach. Measurements: Demographic, perioperative, and pathologic data and postoperative complications were registered. Split renal function (SRF) and effective renal plasma flow (ERPF) were evaluated by renal scintigraphy preoperatively, at 3 and 12 mo postoperatively, then yearly. Baseline weighted differentials (b-WDs) of both SRF and ERPF in the affected kidney were calculated between baseline condition and every time point. Multivariate linear regression was used to find independent variables for increased b-WDs at 3 and 48 mo. P values<0.05 were considered significant. Results and limitations: The SRF and ERPF of kidneys treated by LPN decreased significantly at month 3 and subsequently remained stable through the duration of follow-up. Conversely, neither serum creatinine nor estimated glomerular filtration rate changed significantly during follow-up. The regression model showed statistical significance at month 3 for warm ischemia time (WIT) and age, whereas at 48 mo, statistical significance was reached by WIT alone. No new onset of cardiovascular disease was registered. No evidence of local recurrence was recorded with computed tomography scan. Our study may be underpowered due to small sample size; however, this is one of the largest long-term prospective series using renal scintigraphy to evaluate the renal function after LPN. Conclusions: WIT contributes to irreversible kidney damage observed at month 3 that does not appear to worsen
Satellite interferometric data for landslide intensity evaluation in mountainous regions
Multi-Temporal Interferometric Synthetic Aperture Radar (MTInSAR) data offer a valuable support to landslide mapping and to landslide activity estimation in mountain environments, where in situ measures are sometimes difficult to gather. Nowadays, the interferometric approach is more and more used for wide-areas analysis, providing useful information for risk management actors but at the same time requiring a lot of efforts to correctly interpret what satellite data are telling us. In this context, hot-spot-like analyses that select and highlight the fastest moving areas in a region of interest, are a good operative solution for reducing the time needed to inspect a whole interferometric dataset composed by thousands or millions of points. In this work, we go beyond the concept of MTInSAR data as simple mapping tools by proposing an approach whose final goal is the quantification of the potential loss experienced by an element at risk hit by a potential landslide. To do so, it is mandatory to evaluate landslide intensity. Here, we estimate intensity using Active Deformation Areas (ADA) extracted from Sentinel-1 MTInSAR data. Depending on the localization of each ADA with respect to the urban areas, intensity is derived in two different ways. Once exposure and vulnerability of the elements at risk are estimated, the potential loss due to a landslide of a given intensity is calculated. We tested our methodology in the Eastern Valle d'Aosta (north-western Italy), along four lateral valleys of the Dora Baltea Valley. This territory is characterized by steep slopes and by numerous active and dormant landslides. The goal of this work is to develop a regional scale methodology based on satellite radar interferometry to assess the potential impact of landslides on the urban fabric
Landscape elements, water resources and ecosystem services: their relations to losses and gains in a Pantanal region.
In the last decades, the region of Bonito (Mato Grosso do Sul State - MS) has presented an increase in urban areas, causing impacts on water resources, landscape fragmentation and loss of ecosystem services (ES). Aiming to study the relation chain among land use, water resources and ES, this work determined the influence of the composition from ladscape elements and water quality on the offer of three ES (water quality, erosion control and tourism), also defining the critical points between offer of water services and loss of natural resources for urbanization. For this purpose, the following tasks were accomplished: (i) statistical analysis of Pearson correlation and Principal Components Analysis (PCA) to determine the relations between water quality and mapping classes; (ii) elaboration of equations to determine the ES and (iii) analysis of the relation the quality of ESs and the quantity of urbanized areas in several segments of the Formoso river basin (MS). The results showed that at the sub-basin of Bonito stream, the services presented a degradation of around 80% in relation to the Formoso river basin. Besides that, it was verified that one fourth of the urbanized territory caused around 30% of service losses of water quality.Número especial
Indication to pelvic lymph nodes dissection for prostate cancer: the role of multiparametric magnetic resonance imaging when the risk of lymph nodes invasion according to Briganti updated nomogram is <5
Background: The Briganti updated nomogram (BN) is the most popular predictive model aiming to predict the presence of lymph node invasion (LNI) in patients with prostate cancer (PCa), but it lacks information obtained by preoperative imaging. The primary aim of the study was to evaluate the role of multiparametric prostate magnetic resonance imaging (mp-MRI) in the indication to perform pelvic lymph nodes dissection (PLND) or not in patients with risk of LNI according to BN below 5%. Methods: Since March 2012 and September 2016, 310 patients who underwent a preoperative mp-MRI for staging purpose and subsequent robot-assisted extended PLND (RAEPLND) were retrospectively evaluated. Mp-MRIs were prospectively analyzed by two experienced radiologists. The imaging parameters analyzed were the presence of extracapsular extension (ECE), seminal vesicles invasion (SVI) and predominant Gleason pattern 4 (pG4). All patients underwent RAEPLND by two experienced surgeons with a standardized technique. A dedicated uropathologist performed all pathological analysis. Univariate analysis and multivariate logistic regression analysis were used in order to identify the predictors of LNI in patients with PCa. Results: In the overall population, 57 (18.4%) patients had histologically proven pN1 disease. 48/250 patients (19.2%) with a risk of LNI â¥5% as calculated by the BN were staged pN1 at final histopathological analysis. 9/60 patients (15.0%) with a risk of LNI <5% as calculated by BN, who underwent RAEPLND anyway according to the findings at mp-MRI, were staged pN1 at final histopathological analysis. At multivariate logistic regression analysis, all the three mp-MRI parameters were significant independent predictors of LNI after RAEPLND. Conclusions: The role of mp-MRI seemed to be crucial in patients with a risk of LNI <5% as calculated by the BN. The presence of ECE, SVI, or pG4 at mp-MRI was found to be an independent predictor of LNI by itself
A microspectroscopic study of the electronic homogeneity of ordered and disordered Sr2FeMoO6
Besides a drastic reduction in saturation magnetization of disordered
Sr2FeMoO6 compared to highly ordered samples, magnetizations as a function of
the temperature for different disordered samples may also show qualitatively
different behaviors. We investigate the origin of such diversity by performing
spatially resolved photoemission spectroscopy on various disordered samples.
Our results establish that extensive electronic inhomogeneity, arising most
probably from an underlying chemical inhomogeneity in disordered samples is
responsible for the observed magnetic inhomogeneity. It is further pointed out
that these inhomogeneities are connected with composition fluctuations of the
type Sr2Fe1+xMo1-xO6 with Fe-rich (x>0) and Mo-rich (x<0) regions.Comment: 14 pages, 4 figure
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