Effectiveness of the Chebyshev Approximation in Magnetic Field Line Tracking

The tracking of magnetic field lines can be very expensive, in terms of computational burden, when the field sources are numerous and have complex geometries, especially when accuracy is a priority, because an evaluation of the field is required in many situations. In some important applications, the computational cost can be significantly reduced by using a suitable approximation of the field in the integrated regions. This paper shows how Chebyshev polynomials are well-suited for field interpolation in magnetic field-line tracking, then discusses the conditions in which they are most appropriate, and quantifies the effectiveness of parallel computing in the approximation procedures

Effects of balloon injury on neointimal hyperplasia in steptozotocin-induced diabetes and in hyperinsulinemic nondiabetic pancreatic islet-transplanted rats.

BACKGROUND: The mechanisms of increased neointimal hyperplasia after coronary interventions in diabetic patients are still unknown. METHODS AND RESULTS: Glucose and insulin effects on in vitro vascular smooth muscle cell (VSMC) proliferation and migration were assessed. The effect of balloon injury on neointimal hyperplasia was studied in streptozotocin-induced diabetic rats with or without adjunct insulin therapy. To study the effect of balloon injury in nondiabetic rats with hyperinsulinemia, pancreatic islets were transplanted under the kidney capsule in normal rats. Glucose did not increase VSMC proliferation and migration in vitro. In contrast, insulin induced a significant increase in VSMC proliferation and migration in cell cultures. Furthermore, in VSMC culture, insulin increased MAPK activation. A reduction in neointimal hyperplasia was consistently documented after vascular injury in hyperglycemic streptozotocin-induced diabetic rats. Insulin therapy significantly increased neointimal hyperplasia in these rats. This effect of hyperinsulinemia was totally abolished by transfection on the arterial wall of the N17H-ras-negative mutant gene. Finally, after experimental balloon angioplasty in hyperinsulinemic nondiabetic islet-transplanted rats, a significant increase in neointimal hyperplasia was observed. CONCLUSIONS: In rats with streptozotocin-induced diabetes, balloon injury was not associated with an increase in neointimal formation. Exogenous insulin administration in diabetic rats and islet transplantation in nondiabetic rats increased both blood insulin levels and neointimal hyperplasia after balloon injury. Hyperinsulinemia through activation of the ras/MAPK pathway, rather than hyperglycemia per se, seems to be of crucial importance in determining the exaggerated neointimal hyperplasia after balloon angioplasty in diabetic animals

Error Field and Correction Coils in DTT: a preliminary analysis

The Divertor Tokamak Test (DTT) facility, construction starting at Frascati, Italy, is designed to test different solutions for divertor in view of DEMO. A preliminary analysis of the error fields (EFs) assumed a simplified model of rigid and independent displacements and rotations. A methodology based on the first order truncated Taylor expansion has been applied, linking the displacement parameters and the EFs within the required accuracies. A system of in-vessel copper coils has been designed to counteract EFs and the ampere-turns necessary to force them back within the request limits has been calculated. Here, the details of the analysis have been provided

917-97 Decreased Resistance Against Oxidation of LDL from Patients with Homozigous Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) was the first genetic disorder recognized to cause myocardial infarction. Homozigotes (H) inherit two mutant genes at the low density lipoprotein (LDL) receptor locus, and as a result of the increased levels and prolonged residence time of LDL in plasma, there is a strong tendency toward accumulation of LDL in the arterial wall, causing early atherogenesis. It has been shown that LDL might undergo oxidation before it can be taken up by macrophages and it become foam cells. Thus, one additional explanation for atherogenesis in FH may be the extent to which LDL is susceptible to oxidation. We selected 8 homozigous FH pts (mean total-cholesterol 825±70mg/dl) matched with 8 healthy subjects to investigate the LDL oxidizability. Skin fibroblast cultures showed that one patient was receptor negative, while others were receptor-defective. LDL were isolated from serum by ultracentrifugations in KBr. Purified LDL was exposed to oxygen radicals generated by the xanthine/xanthine oxidase reaction (2mM and 100mU, respectively for 18hs at 37°C). Malonildihaldehyde (MDAI content was evaluated by the thiobarbiturate method. LDL analysis was carried on polyacrylamide (PAGE; 5 to 16% gradient) and agarose gel electrophoresis (0.8% in Tris-HCL buffer). No significant increase was observed in the basal concentration of MDA between LDL from H and controls (0.8±0.12 and 0.9±0.15nmoles of MDAlmg of protein, respectively). Instead, afteroxidation MDAwas 35.1±4.5* nmoles/mg of protein LDL from H, and 23.5±4.1 in controls (*p<0.05). PAGE confirmed the purity of LDL, present as an intact apolipoprotein B100(apo-B100). When oxidized LDL was run on PAGE an extensive apo-B100fragmentation, replaced by lower fragments ranging from 97.400 to 205.000 m.w., was only observed in LDL from H but not in controls in our experimental conditions. MDA content after oxidation of LDL correlated well with the loss of intact apo-B100. Finally, the relative LDL mobility on agarose gel was evaluated. This assay allows to detect changes in electric charge induced by oxidation. Basal LDL from H and controls migrated as homogeneous bands to 1.2±0.2 and 1.1±0.2cm from the origin. In contrast, oxidized LDL from H migrated to 2.1±0.3*cm from the origin while those of controls migrated to 1.5±0.2 (*p<0.05). Thus, in FH LDL appear to be more susceptible to oxidationin vitro; the indices for LDL oxidizability were all significantly different from those of controls. This phenomenon may be an important additional mechanism of atherogenesis in homozigous FH

Numerical Drop Test of a Full Composite Fuselage Section Having Two Components of Velocity

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GDF15 Plasma Level Is Inversely Associated With Level of Physical Activity and Correlates With Markers of Inflammation and Muscle Weakness

Growth differentiation factor 15 (GDF15) is a stress molecule produced in response to mitochondrial, metabolic and inflammatory stress with a number of beneficial effects on metabolism. However, at the level of skeletal muscle it is still unclear whether GDF15 is beneficial or detrimental. The aim of the study was to analyse the levels of circulating GDF15 in people of different age, characterized by different level of physical activity and to seek for correlation with hematological parameters related to inflammation. The plasma concentration of GDF15 was determined in a total of 228 subjects in the age range from 18 to 83 years. These subjects were recruited and divided into three different groups based on the level of physical activity: inactive patients with lower limb mobility impairment, active subjects represented by amateur endurance cyclists, and healthy controls taken from the general population. Cyclists were sampled before and after a strenuous physical bout (long distance cycling race). The plasma levels of GDF15 increase with age and are inversely associated with active lifestyle. In particular, at any age, circulating GDF15 is significantly higher in inactive patients and significantly lower in active people, such as cyclists before the race, with respect to control subjects. However, the strenuous physical exercise causes in cyclists a dramatic increase of GDF15 plasma levels, that after the race are similar to that of patients. Moreover, GDF15 plasma levels significantly correlate with quadriceps torque in patients and with the number of total leukocytes, neutrophils and lymphocytes in both cyclists (before and after race) and patients. Taken together, our data indicate that GDF15 is associated with decreased muscle performance and increased inflammation

Sutureless aortic valve replacement in high risk patients neutralizes expected worse hospital outcome: A clinical and economic analysis

Background: Aortic valve replacement (AVR) by sutureless prostheses is changing surgeon options, although which patients benefit most, as well as their possible economic impact is still to be defined. Methods: Perceval-S prosthesis (LivaNova) is reserved, at the documented Institution, for patients at perceived high surgical risk. This retrospective analysis of outcome and resource consumption compared Perceval with other tissue valves. To clarify the comparison, only patients respecting ‘instructions-for- use’ of Perceval were reviewed. Inclusion criteria: > 65 years, +/– coronary artery bypass grafting, patent foramen ovale closure or myectomy. Exclusion criteria: bicuspid, combined valve or aortic sur- gery. Costs were calculated per patient on a daily basis including preoperative tests, operating costs (hourly basis), disposables, drugs, blood components and personnel. Results: The sutureless group (SU-AVR) had a higher risk profile than the sutured group (ST-AVR). Cardiopulmonary bypass (CPB) and cross-clamp times were significantly shorter in SU-AVR (isolated AVR: cross-clamp 52.9 ± 12.6 vs. 69 ± 15.3 min, p < 0.001; CPB 79.4 ± 20.3 vs. 92.7 ± 18.2 min, p < 0.001). Hospital mortality was 0.9% in SU-AVR and nil in ST-AVR, p = 0.489; intubation 7 (IQR 5–10.7) and 7 h (IQR 5–9), p = 0.785; intensive care unit 1 (IQR 1–1) and 1 day (IQR 1–1), p = 0.258; ward stay 5.5 (IQR 4–7) and 5 days (IQR 4–6), p = 0.002; pacemaker 5.7% (6/106) and 0.9% (1/109), p = 0.063, respectively. Hospital costs (excluding the prosthesis) were $12,825 (IQR 11,733–15,334) for SU-AVR and$12,386 (IQR 11,217–14,230) in ST-AVR, p = 0.055. Conclusions: Despite higher operative risks in SU-AVR, hospital mortality, morbidity and resource consumption did not differ. Operative times were shorter with the sutureless device and this improve- ment, along with more frequent ministernotomy, may have improved many postoperative aims.

Complication of nasal piercing by Staphylococcus aureus endocarditis: a case report and a review of literature

Body piercing, a growing trend especially in young people, is often complicated by severe infections. We present a case of acute bacterial endocarditis by Staphylococcus aureus complicated by multiple cerebral, kidney, spleen embolisms in a young girl, with no known previous cardiac abnormalities, following the piercing of nasal septum. This case highlights the importance of education of patients with and without structural heart disease to the potential dangerous and even life threatening infectious complications of piercing, and stimulate further discussion on the possibility of antibiotic prophylaxis of such procedures

Expression pattern of perilipins in human brain during aging and in Alzheimer's disease

Aims: Perilipins are conserved proteins that decorate intracellular lipid droplets and are essential for lipid metabolism. To date, there is limited knowledge on their expression in human brain or their involvement in brain aging and neurodegeneration. The aim of this study was to characterise the expression levels of perilipins (Plin1-Plin5) in different cerebral areas from subjects of different age, with or without signs of neurodegeneration. Methods: We performed real-time RT-PCR, western blotting, immunohistochemistry and confocal microscopy analyses in autoptic brain samples of frontal and temporal cortex, cerebellum and hippocampus from subjects ranging from 33 to 104 years of age, with or without histological signs of neurodegeneration. To test the possible relationship between Plins and inflammation, correlation analysis with IL-6 expression was also performed. Results: Plin2, Plin3 and Plin5, but not Plin1 and Plin4, are expressed in the considered brain areas with different intensities. Plin2 appears to be expressed more in grey matter, particularly in neurons in all the areas analysed, whereas Plin3 and Plin5 appear to be expressed more in white matter. Plin3 seems to be expressed more in astrocytes. Only Plin2 expression is higher in old subjects and patients with early tauopathy or Alzheimer's disease and is associated with IL-6 expression. Conclusions: Perilipins are expressed in human brain but only Plin2 appears to be modulated with age and neurodegeneration and linked to an inflammatory state. We propose that the accumulation of lipid droplets decorated with Plin2 occurs during brain aging and that this accumulation may be an early marker and initial step of inflammation and neurodegeneration