58 research outputs found
Data assimilation experiments over Europe with the Chemical Transport Model FARM
No full textChemical Transport Models (CTM) and air quality measurements provide complementary information on atmospheric composition. Their melding improves accuracy, important for air quality studies and to support policy makers. An assimilation scheme based on 3D-Var / OI has been developed and implemented for the CTM FARM, core of the MINNI modelling system, which is operational within the regional Copernicus Atmospheric Monitoring Service (CAMS). The scheme assimilates O3, NO2, CO, SO2, PM10 and PM2.5 concentration observations from ground stations and it can be adapted to other pollutants. Two assimilation experiments are validated with independent observations, and compared with a simulation and with CAMS Validated ReAnalysis (VRA) for the year 2018 over the European domain. Both experiments expectedly improve on the free simulation control run, and their scores are consistent with those of the VRA ensemble. In the second experiment the Spatial Consistency Test (SCT) is employed to precisely pinpoint observations affected by large errors and to prevent their assimilation. This significantly improves results that compare very well with the reanalysis ensemble median
Tuberculosis of the knee: A case report and literature review
No full textTuberculosis (TB) is currently in resurgence due to immigration from endemic areas. Skeletal TB frequently mimics more common etiologies and can be difficult to diagnose. A case of TB knee arthritis in a young woman with painful and swelling knee is reported here. Arthrotomy was performed and inflamed synovial tissue was found, with multiple rice bodies in the eroded lateral femoral condyle. The patient was treated with an antituberculosis polytherapy and at 1-year follow-up, she reported relief from pain and swelling. We believe that all surgeons assessing patients from TB endemic regions have to adopt an updated approach toTB treatment. Thus, a literature review is also reported here on the current strategies used in different knee TB cases
Recommended from our members
Adaptive observations and assimilation in the unstable subspace by breeding on the data-assimilation system
No full textResults of targeting and assimilation experiments in a quasi-geostrophic atmospheric model are presented and discussed. The basic idea is to assimilate observations in the unstable subspace (AUS) of the data-assimilation system. The unstable subspace is estimated by breeding on the data-assimilation system (BDAS). The analysis update has the same local structure as the observationally forced bred modes.
Use of adaptive observations, taken at locations where bred vectors have maximum amplitude, enhances the efficiency of the procedure and allows the use of a very limited number of observations and modes. The performance of the targeting and assimilation design is tested in an idealized context, under perfect model conditions. It is shown that the process of driving the control solution toward the true trajectory accomplished by the assimilation reduces the number and growth of unstable modes. By observing and assimilating the unstable structures it is then possible to stabilize the assimilation system so that few observations are sufficient to keep the analysis error within very low bounds, even in the presence of observational noise.
In an idealized limited area model configuration the number and frequency of observations necessary to control the system is shown to be related to the properties of its unstable subspace
Surgical Treatment of Objective Patellar Instability: Long-Term Results
No full text
Purpose To evaluate the long-term results of classical “à la carte” surgical treatment of objective patellar instability as proposed by Dejour in 1987.
Methods A multicentric retrospective study was conducted evaluating patients that underwent surgical procedure with a 10-year minimum follow-up (mean 12.7; range, 10–15). Surgical procedures were medial transfer of the tibial tubercle transfer according to Elmslie and Trillat et al in 38 cases, plasty of the vastus medialis obliquus according to Insall in 15 cases, open lateral retinacular release in 13 cases, capsuloplasty in 3 cases, and trochleoplasty in 1 case. Different combinations of surgical procedures were adopted according to the pathological features. Subjective outcome was assessed with the visual analog scale (VAS), Kujala score, subjective International Knee Documentation Committee (IKDC) score, Tegner score, and Crosby and Insall scale. Radiographic exams were used to assess the patellar tilt by the Laurin's angle and patellofemoral osteoarthritis (OA) according to the Iwano radiological OA scale.
Results Forty patients were evaluated. Subjectively, 60% of patients achieved a result judged good, 34% sufficient, and 6% poor. There were only two cases of recurrence of instability. Mean score results were Kujala score 73.4 ± 9.9 (range, 55–95), VAS 4.5 ± 1.2 (range, 1–6), IKDC 64.8 ± 7.9 (range, 51–88), and Tegner score 4. Only nine patients returned to sports activities). Ten patients developed a grade I patellofemoral OA, 8 patients a grade II, and 22 patients a grade III. Average patellar tilt was 10° ± 3.9°.
Conclusion This retrospective study showed that the traditional surgical procedure was successful for the treatment of patellar instability, but it did not prevent symptomatic patellofemoral OA.
Level of Evidence Level IV, retrospective case series.</jats:p
Patellofemoral instability: classification and imaging
No full textPatellofemoral disorders must be approached through an appropriate process of diagnostic framing, performed using language that is, as far as possible, unequivocal and a validated and organic classification system. At present, the classification proposed by the Lyonnaise school, which fulfills these requirements, is the most complete. This classification divides patellofemoral disorders into three groups: objective patellar instability, potential patellar instability and painful patella syndrome. It also identifies three principal factors of instability: trochlear dysplasia, abnormal patellar height and pathological tibial tubercle-trochlear groove (TT-TG) distance. Imaging is crucial for correct classification and for identifying and measuring the principal factors of instability. Up to now, the emphasis has been placed on the contribution made by traditional diagnostic radiology and computed tomography. In recent years, however, growing attention has been paid to the use of magnetic resonance imaging in the assessment of the patellofemoral joint and in the study of factors of instability, even though there is still a need for validation of this approach before it can be routinely used in preoperative planning
Recommended from our members
Data assimilation as a nonlinear dynamical systems problem : stability and convergence of the prediction-assimilation system
No full textWe study prediction-assimilation systems, which have become routine in meteorology and oceanography and are rapidly spreading to other areas of the geosciences and of continuum physics. The long-term, nonlinear stability of such a system leads to the uniqueness of its sequentially estimated solutions and is required for the convergence of these solutions to the system's true, chaotic evolution. The key ideas of our approach are illustrated for a linearized Lorenz system. Stability of two nonlinear prediction-assimilation systems from dynamic meteorology is studied next via the complete spectrum of their Lyapunov exponents; these two systems are governed by a large set of ordinary and of partial differential equations, respectively. The degree of data-induced stabilization is crucial for the performance of such a system. This degree, in turn, depends on two key ingredients: (i) the observational network, either fixed or data-adaptive, and (ii) the assimilation method
Mediastinistis and pleural empyema after odontogenetic abscess: two cases report and review of the literature
No full textFeasibility of 3D printing in manufacturing hollow vaginal rings for the treatment of vaginosis
No full text3D printing of partially-coated floating systems for controlled release of drugs into the stomach
No full textThis work focused on the development of a retentive drug delivery system (DDS) able to float in the gastric fluids and to ensure prolonged release of drugs over a pre-defined period of time, being then safely emptied from the stomach. To this end, the design step played a pivotal role. The device was thus devised to be composed of a polyvinyl alcohol-based matrix with a tapered geometry, which was partially coated with an insoluble layer of thermoplastic elastomer. This way, release of allopurinol (ALP), used as model drug, could occur only from the uncoated surfaces, while the peculiar geometry of the hydrophilic swellable/erodible matrix was intended to balance the increase in the diffusional path over time with a wider release area. In addition, the coating featured air pockets, whose volume was sized to compensate for the weight force of the DDS once immersed in gastric fluids, thus ensuring its long-lasting buoyancy. By easing the entrance of gastric fluids when the matrix is completely exhausted, such air pockets would also favor sinking and removal of the DDS from the pylorus. Given the multi-layered geometry of the final floating device, including hard-to-fabricate details (e.g. uncoated surfaces, voids), fused deposition modeling 3D printing was identified as the technique of choice for its effectiveness in manufacturing complex shapes. Various formulations were tested for fabricating both the inner matrix and the outer coating, assessing their thermo-mechanical properties, printability and release behavior. The gastro-retentive system demonstrated prolonged buoyancy (> 12 h) and a wide portfolio of ALP release performances, differing in rate and duration, which would make it a promising platform for personalized delivery of drugs in the upper gastrointestinal tract
INJECTABLE SODIUM ALGINATE BASED HYDROGEL WITH METRONIDAZOLE IN 3D PRINTED RESERVOIR FOR PROLONGED RELEASE
No full text- …
