Strand wire winding method in a solenoidal coil with limited geometry for good impedance matching

This paper reports a new strand wire winding method in a solenoidal coil with limited geometry that enables good impedance matching. In the proposed method strand wires are wound layer-by-layer on top of each other allowing one to set equivalent inductance and resistance of the coil to desired values while obtaining dense magnetic flux and high current carrying capacity. As a proof-of-concept demonstration, simple model setups were constructed with solenoidal coils composed of copper wire strands wound according to the proposed method, and a plastic pipe. The measurements were repeated with a metal shell placed inside the coil to model a complete heating system. System inductance and resistance were measured at two different frequencies. The results show that with the new winding method it is possible to increase a coil’s turn number and the number of strand layers composed by the coil. Also, adding and removing strand layers in the proposed coil architectures enable inductance and resistance values to decrease and increase, respectively, in a controlled way. To understand changes of system parameters, simulations were also performed. The calculated inductance and resistance values in the simulations agree well with the measurement results and magnetic flux distribution created in the system demonstrates the changes

Persistent Left Superior Vena Cava and Partial Anomalous Pulmonary Venous Return in an Old Asymptomatic Female Patient

Persistent left superior vena cava is a rare congenital venous anomaly. It results from failure of closure of the left anterior cardinal vein during cardiac development. It is usually asymptomatic but can be associated with other congenital cardiac defects including atrial septal defects, ventricular septal defects, endocardial cushion defects, tetralogy of Fallot and rhythm disturbances. PLSVC should be considered in the presence of a dilated coronary sinus on transthoracic echocardiography. The diagnosis can be made when injection of contrast in left antecubital vein results in enhancement of the dilated coronary sinus before right atrium. MRI, CT-scan and catheterisation can be used to confirm the diagnosis

A gaze independent brain-computer interface based on visual stimulation through closed eyelids

A classical brain-computer interface (BCI) based on visual event-related potentials (ERPs) is of limited application value for paralyzed patients with severe oculomotor impairments. In this study, we introduce a novel gaze independent BCI paradigm that can be potentially used for such end-users because visual stimuli are administered on closed eyelids. The paradigm involved verbally presented questions with 3 possible answers. Online BCI experiments were conducted with twelve healthy subjects, where they selected one option by attending to one of three different visual stimuli. It was confirmed that typical cognitive ERPs can be evidently modulated by the attention of a target stimulus in eyes-closed and gaze independent condition and further classified with high accuracy during online operation (74.58% ± 17.85 s.d.; chance level 33.33%), demonstrating the effectiveness of the proposed novel visual ERP paradigm. Also, stimulus-specific eye movements observed during stimulation were verified as reflex responses to light stimuli and they did not contribute to classification. To the best of our knowledge, this study is the first to show the possibility of using a gaze independent visual ERP paradigm in an eyes-closed condition, thereby providing another communication option for severely locked-in patients suffering from complex ocular dysfunctions.BMBF, 01GQ0850, Bernstein Fokus Neurotechnologie - Nichtinvasive Neurotechnologie für Mensch-Maschine InteraktionBMBF, 16SV5839, Maschinelles Lernen zur Optimierung der Kommunikation schwerstgelähmter Patienten per BC

New Pulmonary Valvuloplasty Technique by Use of an Hourglass-Shaped Balloon in 3 Adults with Severe Pulmonary Valve Stenosis

Percutaneous balloon pulmonary valvuloplasty is the preferred therapy for pulmonary valve stenosis. However, the designs of the cylindrical balloons historically used for valvuloplasty have limitations, especially in patients who have large pulmonary annular diameters. The hourglass-shaped V8 Aortic Valvuloplasty Balloon may prove to be an effective alternative. The balloon has 2 large bulbous segments that are separated by a narrowed waist. The geometric shape is maintained throughout inflation, improving fixation and enabling broader leaflet opening. We present our first experience with the V8 balloon in 3 adults who had severe, symptomatic pulmonary valve stenosis. In addition to describing their cases, we detail our sizing technique for pulmonary valvuloplasty with the V8 balloon. Our successful results suggest that the V8 balloon is efficient and safe for balloon pulmonary valvuloplasty in adults with severe pulmonary valve stenosis

Hemoglobin is inversely related to flow-mediated dilatation in chronic kidney disease

The microcirculation is regulated by oxygen gradients and by endothelial release of nitric oxide, which can react with hemoglobin to form S-nitroso derivatives. Here we induced flow-mediated dilatation of the brachial artery in response to ischemia in 141 non-diabetic patients with stage 3–4 chronic kidney disease who had no history of smoking, cardiovascular events or use of erythropoietin-based agents. Patients with hemoglobin concentrations above the cohort median of 11.6 g/dl were found to have significant reductions in flow-mediated dilatation compared to those below the median. This inverse relationship remained significant after adjustment for potential confounders, including insulin sensitivity, glomerular filtration rate, proteinuria, body mass index, serum urate, etiology of underlying renal disease, treatment with anti-hypertensive drugs, and traditional Framingham risk factors. Given that hemoglobin can act as an important nitric oxide carrier and buffer, our studies suggest that the mechanism by which hemoglobin influences the endothelium-dependent microcirculation requires its nitrosylation; however, more direct studies need to be performed

FGF-23 and vascular dysfunction in patients with stage 3 and 4 chronic kidney disease

Studies in animals show that fibroblast growth factor (FGF)-23 interferes with vascular reactivity induced by the nitric oxide (NO) system. To investigate the relationship between circulating FGF-23 levels and the response of forearm blood flow to ischemia (flow-mediated vasodilatation, FMD) and nitroglycerin, we tested 183 patients with stage 3-4 chronic kidney disease (CKD). None of them had cardiovascular complications or were taking drugs interfering with vascular function. Patients with FGF-23 levels above the median had significantly lower glomerular filtration rate, FMD, and fetuin-A levels (an anti-inflammatory molecule and potent inhibitor of calcification). They also had higher proteinuria and phosphate levels when compared to patients whose FGF-23 levels were below the median. The response to nitroglycerin was not different between the two groups. Multiple regression analysis showed that the relationship between FGF-23 and FMD was only modestly sensitive to adjustment for classical risk factors, biomarkers of bone mineral metabolism, high-sensitivity C-reactive protein, and homeostatic model assessment index. Adjustment for asymmetrical dimethyl arginine (ADMA) weakened the strength of this link; however, it remained highly significant. There was no independent association between FGF-23 and nitroglycerin. Thus, attenuation of FMD by ADMA suggests that this endogenous inhibitor of NO synthase may, in part, mediate the vascular effects of FGF-23 in patients with CKD. © 2010 International Society of Nephrology

Effects of Pre-strain and Temperature on Bake Hardening of TWIP900CR Steel

WOS: 000352865600012The effects of pre-strain and baking temperature on bake hardening behaviour of TWIP900CR steel were investigated. The results reveal that the bake hardening process contributes to an increase in yield strength up to 65 MPa at the baking temperature of 200 degrees C. The difference in yield strength between baking temperatures of 170 and 200 degrees C is almost insignificant. It is clearly observed that baking at a high temperature does not result in a significant increase in yield strength. For a reasonable bake hardening, a good combination of pre-strain and baking temperature is necessary. Besides, the toughness of the material is found to decrease with increasing pre-strain

May oxytocin be a trait marker for bipolar disorder?

WOS: 000330824400007PubMed ID: 24080188There is evidence to suggest that oxytocin is effective in stabilizing mood in humans. Lower plasma oxytocin levels have been reported in patients with major depression. The objective of this study was to investigate serum oxytocin levels during manic and depressive episodes and in the remission period in patients with bipolar disorder. Twenty-two patients in manic episode, 21 in depressive episode, and 24 in remission at the initial phase, ranging from 18 to 65 years of age, who were diagnosed with BD Type I and 24 healthy individuals were included in this study. Blood samples were collected from subjects in the morning at the beginning of the study. A second blood sampling was obtained from manic and depressive patients after response to treatment. MANCOVA was performed to compare the oxytocin values of the groups. The serum oxytocin levels of patients in manic episode were statistically significantly higher than those of the depressive episode and remission groups and of the healthy subjects. The serum oxytocin levels of patients in the depressive episode group and in the remission group were statistically significantly higher than those of the control group. The serum oxytocin levels of the manic episode and depressive episode patients after response to treatment were statistically significantly higher than those of the control group, and there was no statistically significant difference between the patient groups in serum oxytocin levels. The higher oxytocin levels observed in patient groups, compared to the controls, before and after response to treatment suggest that oxytocin may be a trait marker in BD. (C) 2013 Elsevier Ltd. All rights reserved.Erciyes University Scientific Research UnitErciyes University [TSU-10-3046]Erciyes University Ethical Committee approved of the study with the number 2010/24 on 06 May, 2010. Erciyes University Scientific Research Unit funded the study with the project number TSU-10-3046

Wireless Metal Detection and Surface Coverage Sensing for All-Surface Induction Heating

All-surface induction heating systems, typically comprising small-area coils, face a major challenge in detecting the presence of a metallic vessel and identifying its partial surface coverage over the coils to determine which of the coils to power up. The difficulty arises due to the fact that the user can heat vessels made of a wide variety of metals (and their alloys). To address this problem, we propose and demonstrate a new wireless detection methodology that allows for detecting the presence of metallic vessels together with uniquely sensing their surface coverages while also identifying their effective material type in all-surface induction heating systems. The proposed method is based on telemetrically measuring simultaneously inductance and resistance of the induction coil coupled with the vessel in the heating system. Here, variations in the inductance and resistance values for an all-surface heating coil loaded by vessels (made of stainless steel and aluminum) at different positions were systematically investigated at different frequencies. Results show that, independent of the metal material type, unique identification of the surface coverage is possible at all freqeuncies. Additionally, using the magnitude and phase information extracted from the coupled coil impedance, unique identification of the vessel effective material is also achievable, this time independent of its surface coverage