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We study a bio-medical fluid flow simulation using the incompressible, laminar OpenFOAM flow solver icoFoam using iterative linear equation solver and 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 flow 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. 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 [31]). We achieved scaled speed-up for the largest matrices of 64 million $$\times 64$$×64 million in our dataset to run up to 16,384 cores. In other words, we find that the scalability improves as the problem size increases for this application. As the matrix size quadrupled, the speed-up improves at least 50 % near speed-up saturation point. 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 16,384 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.

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.

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.

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.

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.

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.