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This study aimed to evaluate the short- and mid-term results of plica excision in patients with mediopatellar plica and associated cartilage degeneration. Seventy-six surgically treated patients with mediopatellar plica and associated cartilage degeneration at medial femoral condyle (MFC) and/or medial pole of patella were included. Patients were evaluated at baseline, at 6 weeks and 6 months after the operation for their clinical outcomes and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores. The frequency of all signs and symptoms, including all pain parameters, and WOMAC scores were significantly improved compared to baseline, at 6 weeks and 6 months after the operation (P < 0.017). Based on mean WOMAC scores, results of most patients were rated as excellent both at 6 weeks (88%) and at 6 months (94%). Surgical excision of mediopatellar plica associated with cartilage degeneration appears to result in substantial clinical improvement, thus it represents an effective treatment modality.

In many science and engineering applications, problems may result in solving a sparse linear system AX=B. For example, SuperLU_MCDT, a linear solver, was used for the large penta-diagonal matrices for 2D problems and hepta-diagonal matrices for 3D problems, coming from the incompressible blood flow simulation (see [1]). It is important to test the status and potential improvements of state-of-the-art solvers on new technologies. In this work, sequential, multithreaded and distributed versions of SuperLU solvers (see [2]) are examined on the Intel Xeon Phi coprocessors using offload programming model at the EURORA cluster of CINECA in Italy. We consider a portfolio of test matrices containing patterned matrices from UFMM ([3]) and randomly located matrices. This architecture can benefit from high parallelism and large vectors. We find that the sequential SuperLU benefited up to 45 % performance improvement from the offload programming depending on the sparse matrix type and the size of transferred and proc...

It is important to have a scalable parallel numerical parameter optimization algorithm for a dynamical system used in financial applications where time limitation is crucial. We use Message Passing Interface parallel programming and present such a new parallel algorithm for parameter estimation. For example, we apply the algorithm to the asset flow differential equations that have been developed and analyzed since 1989 (see [3-6] and references contained therein). We achieved speed-up for some time series to run up to 512 cores (see [10]). Unlike [10], we consider more extensive financial market situations, for example, in presence of low volatility, high volatility and stock market price at a discount/premium to its net asset value with varying magnitude, in this work. Moreover, we evaluated the convergence of the model parameter vector, the nonlinear least squares error and maximum improvement factor to quantify the success of the optimization process depending on the number of initial parameter vectors.

The purpose of this study was to investigate the effects of exogenous local Insulin like growth factor-I (IGF-I) on the repair of full-thickness articular cartilage defects in immature rabbits.Thirty-six skeletally immature New Zealand rabbits between 6 and 8 weeks old were used. A single defect, 3.5-mm-wide by 4-mm-deep full-thickness articular cartilage defect in the medial femoral condyle, was created. The defect was either filled with a collagen sponge or with a collagen sponge impregnated with 5 mug of recombinant IGF-I. The animals were sacrificed at 4, 8 or 12 weeks, and the repair tissue was examined macroscopically and histologically. Repair tissue was also examined immunohistochemically for the presence of type-I collagen, type-II collagen and PCNA at all weeks.Newly formed tissue in all of the defects in the IGF-I group had the gross, histological and histochemical appearance of a smooth, intact hyaline articular cartilage. The average total scores on the histological grading scale were significantly better (p0.05) for the defects treated with recombinant IGF-I at all time points. Immunostaining with an antibody against type-II collagen showed the diffuse presence of the repair cartilage in the IGF-I treated defects. The control groups demonstrated minimum staining with type-II collagen antibody.These findings suggest that repair of full-thickness immature cartilage defects can be enhanced by recombinant IGF-I.

It is important to estimate the elapsed time to solve large sparse linear systems for time-restricted real life decision making applications such as oil and gas reservoir simulators. Challenging matrices should be distinguished and handled separately because they may lead to performance bottleneck. Therefore, we need to examine the spectral effects of large matrices on the performance of scalable direct solvers by using eigenvalues. In this work, we check whether there is relationship between the eigenvalue distribution of a matrix and the performance of the solver. We try to examine the eigenvalue distribution of various sparse matrices. We may find all eigenvalues in order to obtain the distribution graph of eigenvalues, if possible. However, it is very expensive to find all eigenvalues. Therefore, Gerschgorin's theorem may be used to bound the spectrum of square matrices. Several behaviors such as being disjoint, overlapped or clustered of Gerschgorin circles may give clue regarding the distribution of the eigenvalues and the performance of the solver for that matrix. In this paper, we consider a portfolio of test matrices which include randomly populated sparse matrices and various patterned matrices coming from reservoir modeling from single porosity single permeability to dual porosity dual permeability models (see [10]). We examined our modified HELM2D03LOWER_20K matrix and EMILIA_923 matrix from the University of Florida sparse matrix collection (see [17]), in addition to the patterned matrices from 3 phase black-oil model and 7 component EOS model. We define an optimal minimum number of cores as the number of cores that provides the minimum wall clock time for a given size of problem, where a right match occurs between the problem size, the spectral effects of matrix and the available resources such as memory, in presence of communication overhead. We find that the optimal minimum number of cores required depends on the sparsity level and size of the matrix. As the sparsity level of matrix decreases and the order of matrix increases, we expect that the optimal minimum number of cores increases slightly.

It is significant to perform structural analysis of large sparse matrices in order to obtain scalable direct solvers. In this paper, we focus on spectral analysis of large sparse matrices. We believe that the approach for exception handling of challenging matrices via Gerschgorin circles and using tuned parameters is beneficial and practical to stabilize the performance of sparse direct solvers. Nearly defective matrices are among challenging matrices for the performance of solver. Such matrices should be handled separately in order to get rid of potential performance bottleneck. Clustered eigenvalues observed via Gerschgorin circles may be used to detect nearly defective matrix. We observe that the usage of super-nodal storage parameters affects the number of fill-ins and memory usage accordingly.

Twenty-seven adolescents with 29 femoral shaft fractures, between the ages of 10 and 16 years, were treated with closed flexible Ender intramedullary nailing from 1989 to 1992 in our clinic. In one patient who had a fracture of the distal third of the femoral shaft, the nail was inserted proximal to distal (antegrade nailing). In the other patients, the nails were inserted distal to proximal (retrograde nailing). Clinical and radiological follow up averaged 32 months (18–56 months). Hospitalization averaged 15 days (7–28 days). All fractures healed with one significant leg length discrepancy of 1.7 cm in a patient who had developed osteomyelitis. There was no significant angulation or malrotation. All patients had a normal gait and were able to participate in full activities. There was one deep wound infection in a patient with an open fracture of the femoral shaft. There were no non-unions, delayed-unions or psychological complications. For this age group, this treatment of femoral shaft fracture should be considered owing to the functional recovery with low morbidity and cost, providing early ambulation, early discharge from hospital and early return to school.

International audience; Increasing the value of marine coproducts and territories : territorial issuesThe research question reviews the potential biotechnological ways for adding value to marine wastes, under the constraint of dependency for processing plants regarding the dependency to local territory. The first results of a survey conducted in Northern Brittany allow us to characterize inflows of seafood products and outflows of by-products. Relationship between territorial dependency and biotechnological ways for adding value to marine by-products is discussed. In this respect, increasing international trade of seafood is modifying location strategies of processors and should be taken into account. The traditional link between stakeholders (fishermen, auction markets, processing plants) has then to be reassessed.; La problématique de cette réflexion repose sur l'analyse de la valorisation des coproduits de la mer, tenant compte de la dépendance des entreprises de transformation à l'égard du territoire. Les premiers résultats d'une enquête réalisée dans le nord de la Bretagne permettent d'évaluer les flux des produits traités et la quantité de coproduits générés. La dépendance de la valorisation biotechnologique des coproduits au territoire de la production primaire est analysée. A cet égard, l'ouverture au commerce international des marchés des produits de la mer doit être prise en compte car elle modifie les stratégies de localisation des entreprises de transformation. Le lien historique des acteurs avec leur territoire (pêcheurs, halle à marée, transformateurs) est donc à reconsidérer.

Introduction: The aim of this study was to compare the radiographic results and clinical outcome of unreamed tibial nailing (UTN) and Ilizarov external fixation (IEF) for the treatment of type IIIA open fractures of the tibia. Materials and Methods: Sixty-one patients with open type IIIA tibial shaft fractures were treated with an IEF (n = 32) or UTN (n = 29). Both groups were compared for union time, secondary outcomes of nonunion, infections, mechanical failure of the implant, and malunion. Results: The average time-to-bone healing was 19 weeks (range 14-23 weeks) for IEF and 21 weeks (range 16-36 weeks) for UTN; it was significantly shorter in the IEF group (P = 0.039). One patient had refracture in the IEF group. Malunion occurred in four patients for each group. Posttraumatic osteomyelitis occurred in two patients in the IEF group and in three patients in the UTN group. In the IEF group, additional surgical procedures were indicated in three cases including sequestrectomy (n = 1), and pin replacement (n = 2). In the UTN group, seven patients needed additional surgery including bone grafting (n = 3), nail exchanged (n = 1), and posttraumatic osteomyelitis (n = 3). Conclusion: The results of the current study showed that IEF technique had a notable incidence of pin-tract infection, joint contracture, and shorthening related to treatment of the delayed union. The UTN technique had the disadvantage of a posttraumatic osteomyelitis and delayed union requiring additional surgery. We believe that the decision to use IEF or UTN should be made on a case-by-case basis. © Springer-Verlag 2007.

In 40 patients, we attempted to investigate the efficacy of electromyography-biofeedback (EMG-B) on quadriceps muscle strength after arthroscopic meniscectomy.The patients were randomly divided into two groups each consisting of 20 subjects. For the control group, a classical exercise program was given (five sessions of EMG-B application for 2 weeks postoperatively). Range of motions, Lysholm knee score, EMG electrical activity values of vastus medialis obliques (VMO), and vastus lateralis (VL) were measured pre- and postoperatively on the 3rd and 14th day, and at the 6th week.When the ranges of motion values were compared, a significant difference (for average values of knee flexion angle) was found on the 14th day and 6th week in favour of biofeedback group (p0.05). When Lysholm knee scores on the 14th day and 6th week were compared in the control and biofeedback groups, and maximum contraction and average contraction values of VMO, VL muscles were compared with operated/non-operated %age ratios, there was a statistically significant difference in favour of the biofeedback group (p0.05).Our results showed that EMG-B was an effective treatment modality in improving quadriceps muscle strength after arthroscopic meniscectomy surgery.

We evaluated the results of patients who were treated with Ilizarov external fixation for type II and III open tibial fractures.Forty-five patients (4 females, 41 males; mean age 33 years; range 8 to 65 years) with open tibial fractures were treated with the Ilizarov external fixator. According to the Gustilo-Mendoza classification, the fractures were type II, IIIA, IIIB, and IIIC in 12, 20, 9, and 4 patients, respectively. The mean follow-up was 58 months and 4 days (range 42 months and 10 days to 66 months and 11 days). The fixators were applied for a mean of 17.2 weeks (range 6.8 to 55.7 weeks).Union was achieved in all cases. A significant difference was observed between type II and III fractures in terms of time to union (p0.05). Compared to type IIIA fractures, the time to union was significantly longer in type IIIB and IIIC fractures (p0.05). The most frequent complication was pin-tract infections (27.1%). Refracture occurred in four cases (8.8%). Three patients developed late infections at the fracture site. Radiographically, the results were excellent in 14 patients (31%), good in 22 patients (48.8%), moderate in five patients (11.1%), and poor in four patients (8.8%). Functional results were excellent in 21 patients (46.6%), good in 20 patients (44.4%), and moderate in four patients (8.8%).Despite technical difficulties and problems associated with pin-tract infections, the Ilizarov external fixator may be the preferred technique in open tibial fractures because of high union rates, the use of thin K-wires with minimal traumatic effect, and more successful functional results.

Male and female cousins, the offspring of consanguineous Turkish parents, have been affected by a hitherto unreported combination of problems comprising moderate to severe psychomotor developmental delay, ocular anterior chamber abnormality, facial dysmorphisms (broad, bossed forehead, late-closing fontanelle, telecanthus, downslanting palpebral fissures, posteriorly rotated ears, downturned angles of mouth), arachnodactyly and distal arthrogryposis with severely adducted thumbs and club feet. This striking phenotype has some similarities with the multiple pterygium syndrome (Escobar syndrome), but it most likely represents a distinct condition caused by an autosomal recessive gene defect.

We study a bio-medical fluid flow simulation using the incompressible, laminar OpenFOAM solver icoFoam and other direct solvers (kernel class) such as SuperLU_DIST 3.3 and SuperLU_MCDT (Many-Core Distributed) for the large penta-diagonal and hepta-diagonal matrices coming from the simulation of blood flow in arteries with a structured mesh domain. A realistic simulation for the sloshing of blood in the heart or vessels in the whole body is a complex problem and may take a very long time, thousands of hours, for the main tasks such as pre-processing (meshing), decomposition and solving the large linear systems. We generated the structured mesh by using blockMesh as a mesh generator tool. To decompose the generated mesh, we used the decomposePar tool. After the decomposition, we used icoFoam as a flow simulator/solver. For example, the total run time of a simple case is about 1500 hours without preconditioning on one core for one period of the cardiac cycle, measured on the Linux Nehalem Cluster (see [28]) available at the National Center for High Performance Computing (UHeM) (see [5]). Therefore, this important problem deserves careful consideration for usage on multi petascale or exascale systems. Our aim is to test the potential scaling capability of the fluid solver for multi petascale systems. We started from the relatively small instances for the whole simulation and solved large linear systems. We measured the wall clock time of single time steps of the simulation. This version gives important clues for a larger version of the problem. Later, we increase the problem size and the number of time steps to obtain a better picture gradually, in our general strategy. We test the performance of the solver icoFoam at TGCC Curie (a Tier-0 system) at CEA, France (see [21]). We consider three large sparse matrices of sizes 8 million x 8 million, 32 million x 32 million, and 64 million x 64 million. We achieved scaled speed-up for the largest matrices of 64 million x 64 million to run up to 16384 cores. In other words, we find that the scalability improves as the problem size increases for this application. This shows that there is no structural problem in the software up to this scale. This is an important and encouraging result for the problem. Moreover, we imbedded other direct solvers (kernel class) such as SuperLU_DIST 3.3 and SuperLU_MCDT in addition to the solvers provided by OpenFOAM. Since future exascale systems are expected to have heterogeneous and many-core distributed nodes, we believe that our SuperLU_MCDT software is a good candidate for future systems. SuperLU_MCDT worked up to 16384 cores for the large penta-diagonal matrices for 2D problems and hepta-diagonal matrices for 3D problems, coming from the incompressible blood flow simulation, without any problem.

In this project, we propose a new hybrid algorithm for parameter optimization and implement it using MPI. In particular, we study a scalable parallel nonlinear parameter optimization algorithm with parameter pools for a nonlinear dynamical system called the asset flow differential equations (AFDEs) in R4. We generate time series pairs as proxy to market price and net asset value by using random walk simulation where the volatilities of the time series are similar to that of real closed-end funds traded on New York Stock Exchange (NYSE). When we apply the algorithm by using simulations for a set of time series, we observe that the computed optimal parameter values, average number of quasi-Newton iterations, the average nonlinear least squares errors, and the average maximum improvement factors can converge certain values within corresponding small ranges, after oscillations. Moreover, we tested for 64, 128, 256 and 512 cores using the 512 initial parameter vectors. We achieved speed-up for the time series to run up to 512 cores. The algorithm is applicable for parameter optimization of the related nonlinear dynamical system of differential equations with thousands of parameters as well.

It is significant to perform structural analysis of large sparse matrices in order to obtain scalable direct solvers. In this paper, we focus on spectral analysis of large sparse matrices. We believe that the approach for exception handling of challenging matrices via Gerschgorin circles and using tuned parameters is beneficial and practical to stabilize the performance of sparse direct solvers. Nearly defective matrices are among challenging matrices for the performance of solver. We observe that the usage of super-nodal storage parameters affects the number of fill-ins and memory usage accordingly.

SuperLU_DIST is a distributed memory parallel solver for sparse linear systems. The solver makes several calls to BLAS library routines in its numerical factorization phase. The performance of the BLAS library can significantly affect the overall performance of the solver as the required BLAS operations are typically computationally dense. In this regard, we examine how the overall performance of the SuperLU_DIST solver can be improved by employing optimized BLAS libraries. In particular, we try using Intel Math Kernel Library (MKL) and Parallel Linear Algebra Subroutines for Multicore Architecture (PLASMA) libraries. Using MKL can provide an approximate performance improvement of 50 %, and using PLASMA can improve the performance by around 10 % for the best tile size. Based on our findings, we have improved SuperLU_MCDT solver.

It is important to have a fast, robust and scalable algorithm to solve a sparse linear system AX=B. Many multiscale modelling applications in science and engineering would like to capture more details of the system that results in more general matrices. In this work, we consider scalable direct solvers and, in particular, we examine the effectiveness of the SuperLU_DIST 3.0 for distributed memory and SuperLU_MT 2.0 for shared memory parallel machines. We use test matrices containing randomly populated sparse matrices in addition to patterned matrices. For randomly populated large sparse matrices, we find that numerical factorization, symbolic factorization, and consequently wall clock time spike up around the sparsity level of 7. We propose a new hybrid algorithm utilizing the MPI+OpenMP hybrid programming approach among other modifications to solve large sparse linear systems so that we can avoid extra communication overhead with MPI within node and we could have a better scalability than both pure MPI and OpenMP. It combines the advantages of SuperLU_DIST and SuperLU_MT and diminishes some of their limitations.

We consider a fast, robust and scalable solver using graphic processing units (GPU) as accelerators for a sparse linear system AX=B. In this project, a new parallel hybrid direct solver is designed and implemented on GPU for large sparse linear systems. In particular, we work on GPU programming using directive based Open ACC in order to obtain a scalable and improved SuperLU on CPU+GPU heterogeneous systems. Project ID: FP7-INFRASTRUCTURES-2011-2, PRACE-2IP —PRACE - Second Implementation Phase Project

Ergolines, an Italian SME expert in the design of electromagnetic stirrers for metal casting, and the project partners at ITU collaborated in a European research project under the EU’s Horizon 2020 Research and Innovation Programme, in particular under the SME HPC Adoption Programme in Europe (SHAPE), organized within the PRACE Research Infrastructure. Custom codes were developed for HPC-based magnetohydrodynamics (MHD) simulations, enabling the design of a dedicated electromagnetic stirrer (EMS) for the electric arc furnaces (EAF). We performed parallel simulations using an OpenFOAM solver and other related programs on IBM-FERMI (a PRACE Tier-0 system) at CINECA, Italy. The fluid-dynamics of liquid steel within the EAF under the effect of electromagnetic stirring has been studied under different simulation parameters.