Numerical Simulation of Turbulent Flow in a Pipe Oscillating Around Its Axis

The turbulent flow in a cilindrical pipe oscillating around its lungitudinal axis is studied via direct numerical solution of the Navier-Stokes equations, and compared to the reference turbulent flow in a fixed pipe and in a pipe with steady rotation. The maximum amount of drag reduction achievable with appropriate oscillations of the pipe wall is found to be of the order of 40%, hence comparable to that of similar flows in planar geometry. The transverse shear layer due to the oscillations induces substantial modifications to the turbulence statistics in the near-wall region, indicating a strong effect on the vortical structures. These modifications are illustrated, together with the implications for the drag-reducing mechanisms. A conceptual model of the interaction between the moving wall and a streamwise vortex is discussed

Volume control of the lower limb with graduated compression during different muscle pump activation conditions and the relation to limb circumference variation

Background: The literature supports the use of graduated compression stockings (GCS) for leg edema. Nevertheless, there is a paucity of data on the GCS effect on limb edema related to sitting, standing, and walking. Data of different limb shapes and their impact on GCS-exerted pressure are lacking. This investigation provides evidence-based information on the effect of GCS on edema reduction and the impact of limb circumference gradients on GCS pressure. Methods: Thirty healthy individuals (15 men and 15 women; mean age, 32 ± 5 years) were included. All the participants underwent lower limb volume (Kuhnke formula) measurement, before and after sitting for 30 minutes, wearing below-ankle noncompressive socks. The same assessment was repeated 7 days later, in the same participants, but with wearing of below-knee 16 to 20 mm Hg GCS. At 7-day intervals, 1 week with below-ankle noncompressive socks and 1 week with below-knee 16 to 20 mm Hg GCS, all the participants repeated the same protocol including standing and walking. Ten participants underwent bioimpedance assessment (Biody Xpert II; eBIODY, La Ciotat, France) before and after sitting, standing, and walking. In the same group, B and B1 interface pressure values were measured. Results: Data collection was completed in all 60 limbs. Sitting or walking without GCS led to no significant volume changes, whereas volume was decreased by the use of GCS (−4.8% [P <.00001] and −4.4% [P <.00001], respectively). Standing up without GCS led to an increase in volume (2.7%; P <.0001), whereas limb volume was decreased (4.6%; P <.0001) by use of GCS. Bioimpedance showed extracellular water reduction only while walking with GCS (from 40.55% ± 1.66% to 40.45% ± 1.71%; P <.017). Mean interface pressure was 19 ± 5 mm Hg (B) and 16 ± 5 mm Hg (B1). The interface pressure variation from B to B1 was not homogeneous among participants (mean percentage variation of −13% ± 25%, ranging from −54% to 16%). A negative linear trend between pressure variation and circumference percentage increase was found; the subanalysis excluding the two outliers showed a strong negative linear correlation (Pearson coefficient r = −0.96). Conclusions: GCS led to a significant limb volume reduction irrespective of limb position and muscle pump function. However, extracellular fluid is mobilized only during muscle contraction while walking with GCS. Interestingly, different lower limb circumference variations influence the interface pressure gradient, indicating the importance of proper fitting of both B and B1 during prescription. These data provide a foundation to future investigations dealing with GCS effect on fluid mobilization and with limb geometry impact on compression performance

Academic conflict of interest

PURPOSE: We set out to summarize the current challenges in academic conflict of interest. METHODS: This is a narrative review by a multidisciplinary, multinational panel of academic officers including deans of medical/pharmacy schools. RESULTS AND CONCLUSIONS: Disclosing conflict of interest has become the appropriate professional behavior since the 1990s in response to the necessity to fix moral and financial fences around medical activities. The nature of the conflict of interest is academic when either the conflict relates to academic duties and/or the nature of the interest is academic. People usually distinguish between real conflict of interest, when private interest overtly influences one\u27s professional obligations; potential conflict of interest, when there is no obvious direct link between a person interests and current duties without ruling out that expected changes in duties cause a situation of conflict; and apparent conflict of interest, when the risk does not really exist, but serious doubts remain. Areas at risk of academic conflict of interest include peer review process for grant evaluation or journals, scientific communications such as elaborating and disseminating clinical guidelines, lecturing at meeting, advising decision-makers, teaching activities, and mentoring. The management of academic conflict of interest should consider actions in four domains, i.e., education, prevention, measures for enforcement and solving, and communication. Academic conflicts of interest are as frequent as financial conflicts but more difficult to identify and assess, and much less addressed in the literature. Generating more evidence from high-quality research is mandated to improve the management of academic and more generally non-financial conflicts of interest

Effectiveness of complete conservative treatment for adolescent idiopathic scoliosis (bracing and exercises) based on SOSORT management criteria: results according to the SRS criteria for bracing studies - SOSORT Award 2009 Winner

<p>Abstract</p> <p>Background</p> <p>The SRS criteria give the methodological reference framework for the presentation of bracing results, while the SOSORT criteria give the clinical reference framework for an appropriate bracing treatment. The two have not been combined in a study until now. Our aim was to verify the efficacy of a complete, conservative treatment of Adolescent Idiopathic Scoliosis (AIS)according to the best methodological and management criteria defined in the literature.</p> <p>Methods</p> <p>Study Design. Retrospective study. Population. We included all AIS patients respecting the SRS inclusion criteria (age 10 years or older; Risser test 0-2; Cobb degrees 25-40°; no prior treatment; less than one year post-menarchal) who had reached the end of treatment since our institute database start in 2003. Thus we had 44 females and four males, with an age of 12.8 ± 1.6 at the commencement of the study. Methods. According to individual needs, two patients have been treated with Risser casts followed by Lyon brace, 40 with Lyon or SPoRT braces (14 for 23 hours per day, 23 for 21 h/d, and seven for 18 h/d at start), and two with exercises only (1 male, 1 female): these were excluded from further analysis. Outcome criteria. SRS (unchanged; worsened 6° or more; over 45° at the end of treatment; surgically treated; two years' follow-up); clinical (ATR, Aesthetic Index, plumbline distances); radiographic (Cobb degrees); and ISICO (optimal; minimal). Statistics. Paired ANOVA and t-test, Tukey-Kramer and chi-square test.</p> <p>Results</p> <p>Median reported compliance during the 4.2 ± 1.4 treatment years was 90% (range 5-106%). No patient progressed beyond 45°, nor was any patient fused, and this remained true at the two-year follow-up for the 85% that reached it. Only two patients (4%) worsened, both with single thoracic curve, 25-30° Cobb and Risser 0 at the start. We found statistically significant reductions of the scoliosis curvatures (-7.1°): thoracic (-7.3°), thoracolumbar (-8.4°) and lumbar (-7.8°), but not double major. Statistically significant improvements have also been found for aesthetics and ATR.</p> <p>Conclusion</p> <p>Respecting also SOSORT management criteria and thus increasing compliance, the results of conservative treatment were much better than what had previously been reported in the literature using SRS criteria only.</p

Forces exerted during exercises by patients with adolescent idiopathic scoliosis wearing fiberglass braces

OBJECTIVE: To quantify and compare the forces exerted by scoliosis patients in fiberglass braces during exercises usually prescribed in departments where casts are made. The exercises are intended to increase corrective forces, activate muscles, stimulate ventilation and help the patient psychologically. SETTING: Outpatient care. PATIENTS: 17 consecutive adolescent patients wearing fiberglass brace for idiopathic scoliosis. INTERVENTIONS: Exercises (kyphotization, rotation, "escape from the pad") in different positions (sitting, supine, on all fours). MAIN OUTCOME MEASURE: Pressure detected by the F-Socket System between the rib hump and the pad of the brace. RESULTS: In static and dynamic conditions, the position adopted did not alter the total pressure exerted by the brace, although the part of the sensor stimulated did vary. Kyphotization and rotation exercises produced a significant increase of pressure (+ 58.9% and +29.8%, respectively); however, the "escape from the pad" exercise, despite its name, did not produce any significant variation of pressure. CONCLUSION: Exercises in the brace allow adjunctive forces to be applied on soft tissues and through them, presumably on the spine. Different exercises can be chosen to obtain different actions. Physical exercises and sporting activities are useful in mechanical terms, although other important actions should not be overlooked

Detection of BRCA1, BRCA2, and ATM Alterations in Matched Tumor Tissue and Circulating Tumor DNA in Patients with Prostate Cancer Screened in PROfound.

PURPOSE: Not all patients with metastatic castration-resistant prostate cancer (mCRPC) have sufficient tumor tissue available for multigene molecular testing. Furthermore, samples may fail because of difficulties within the testing procedure. Optimization of screening techniques may reduce failure rates; however, a need remains for additional testing methods to detect cancers with alterations in homologous recombination repair genes. We evaluated the utility of plasma-derived circulating tumor DNA (ctDNA) in identifying deleterious BRCA1, BRCA2 (BRCA), and ATM alterations in screened patients with mCRPC from the phase III PROfound study. EXPERIMENTAL DESIGN: Tumor tissue samples were sequenced prospectively at Foundation Medicine, Inc. (FMI) using an investigational next-generation sequencing (NGS) assay based on FoundationOne®Liquid to inform trial eligibility. Matched ctDNA samples were retrospectively sequenced at FMI, using an investigational assay based on FoundationOne®Liquid CDx. RESULTS: 81% (503/619) of ctDNA samples yielded an NGS result, of which 491 had a tumor tissue result. BRCA and ATM status in tissue compared with ctDNA showed 81% positive percentage agreement and 92% negative percentage agreement, using tissue as reference. At variant-subtype level, using tissue as reference, concordance was high for nonsense (93%), splice (87%), and frameshift (86%) alterations but lower for large rearrangements (63%) and homozygous deletions (27%), with low ctDNA fraction being a limiting factor. CONCLUSIONS: We demonstrate that ctDNA can greatly complement tissue testing in identifying patients with mCRPC and BRCA or ATM alterations who are potentially suitable for receiving targeted PARP inhibitor treatments, particularly patients with no or insufficient tissue for genomic analyses

Brace technology thematic series - The Sforzesco and Sibilla braces, and the SPoRT (Symmetric, Patient oriented, Rigid, Three-dimensional, active) concept

<p>Abstract</p> <p>Background</p> <p>Bracing is an effective strategy for scoliosis treatment, but there is no consensus on the best type of brace, nor on the way in which it should act on the spine to achieve good correction. The aim of this paper is to present the family of SPoRT (Symmetric, Patient-oriented, Rigid, Three-dimensional, active) braces: Sforzesco (the first introduced), Sibilla and Lapadula.</p> <p>Methods</p> <p>The Sforzesco brace was developed following specific principles of correction. Due to its overall symmetry, the brace provides space over pathological depressions and pushes over elevations. Correction is reached through construction of the envelope, pushes, escapes, stops, and drivers. The real novelty is the drivers, introduced for the first time with the Sforzesco brace; they allow to achieve the main action of the brace: a three-dimensional elongation pushing the spine in a down-up direction.</p> <p>Brace prescription is made plane by plane: frontal (on the "slopes", another novelty of this concept, i.e. the laterally flexed sections of the spine), horizontal, and sagittal. The brace is built modelling the trunk shape obtained either by a plaster cast mould or by CAD-CAM construction. Brace checking is essential, since SPoRT braces are adjustable and customisable according to each individual curve pattern.</p> <p>Treatment time and duration is individually tailored (18-23 hours per day until Risser 3, then gradual reduction). SEAS (Scientific Exercises Approach to Scoliosis) exercises are a key factor to achieve success.</p> <p>Results</p> <p>The Sforzesco brace has shown to be more effective than the Lyon brace (matched case/control), equally effective as the Risser plaster cast (prospective cohort with retrospective controls), more effective than the Risser cast + Lyon brace in treating curves over 45 degrees Cobb (prospective cohort), and is able to improve aesthetic appearance (prospective cohort).</p> <p>Conclusions</p> <p>The SPoRT concept of bracing (three-dimensional elongation pushing in a down-up direction) is different from the other corrective systems: 3-point, traction, postural, and movement-based. The Sforzesco brace, being comparable to casting, may be the best brace for the worst cases.</p