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Background Reperfusion networks have permitted improvements in reperfusion delays in primary percutaneous coronary intervention (PPCI)-treated ST elevation myocardial infarction (STEMI). However, the impact on myocardial salvage (MS) of direct transfer to the catheterization laboratory (cath-lab) to minimize system delay remains unknown. Objective We sought to quantify the myocardial salvage index (MSI) acutely and to assess adverse remodeling at 6 months in PPCI-treated STEMI according to the mode of patient presentation. Methods Between 2005 and 2021 we included 493 patients in a single center registry of first PPCI-treated STEMI who were studied with Late gadolinium enhanced (LGE) cardiac magnetic resonance (CMR) in the acute phase. Among them, 414 (84.0%) underwent a second LGE-CMR at 6 months. Subjects were classified depending on the mode of presentation: those diagnosed out-of-hospital and directly transferred to the cath-lab by the Emergency Medical Services (EMS group, 29.82%); subjects with first medical contact in a PCI-capable hospital (PCI-H group, 41.75%); and patients presenting to a non-PCI-capable center and transferred for PCI (non-PCI-H group, 28.43%). We computed the angiographic area at risk by BARI score, and combined it with the LGE-CMR derived infarct size to compute a validated MSI, expressed as percentage of area at risk. The change in ejection fraction (EF) and indexed left ventricle end-diastolic volume (iLVEDV) from baseline to 6 months was also computed. Results The mean age was 58.9±11.9 years, 84.5% were male and 51.4% had anterior STEMI. Total median ischaemic time was (median (interquartile range)) 126 (105–161) min in the EMS group, 201 (145–321) min in the PCI-H group and 300 (173–592) min in the non-PCI-H group (p Conclusions Patients with out-of-hospital diagnostis of STEMI by the EMS who were directly transferred to the cath-lab showed shorter total ischaemic times, resulting in increased myocardial salvage and a trend towards improved indexes of left ventricular function at 6 months. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Grant from La Maratό de TV3 and grant from Fundaciό La Caixa

SIGNALS, the Star formation, Ionized Gas, and Nebular Abundances Legacy Survey, is a large observing programme designed to investigate massive star formation and HII regions in a sample of local extended galaxies. The programme will use the imaging Fourier transform spectrograph SITELLE at the Canada-France-Hawaii Telescope. Over 355 h (54.7 nights) have been allocated beginning in fall 2018 for eight consecutive semesters. Once completed, SIGNALS will provide a statistically reliable laboratory to investigate massive star formation, including over 50 000 resolved HII regions: the largest, most complete, and homogeneous data base of spectroscopically and spatially resolved extragalactic HII regions ever assembled. For each field observed, three datacubes covering the spectral bands of the filters SN1 (363386 nm), SN2 (482-513 nm), and SN3 (647-685 nm) are gathered. The spectral resolution selected for each spectral band is 1000, 1000, and 5000, respectively. As defined, the project sample will facilitate the study of small-scale nebular physics and many other phenomena linked to star formation at a mean spatial resolution of similar to 20 pc. This survey also has considerable legacy value for additional topics, including planetary nebulae, diffuse ionized gas, and supernova remnants. The purpose of this paper is to present a general outlook of the survey, notably the observing strategy, galaxy sample, and science requirements.© 2019 The Author(s).Published by Oxford University Press on behalf of the Royal Astronomical Society, This research was based on observations obtained at the CFHT, which is operated from the summit of Mauna Kea by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii. The authors wish to recognize and acknowledge the very significant cultural role that the summit of Mauna Kea has always had within the indigenous Hawaiian community. The authors are most grateful to have the opportunity to conduct observations from this mountain. The observations were obtained with SITELLE, a joint project between Universite Laval, ABB-Bomem, Universite deMontreal, and the CFHT, with funding support from the Canada Foundation for Innovation (CFI), the National Sciences and Engineering Research Council of Canada (NSERC), Fonds de Recherche du Quebec -Nature et Technologies (FRQNT), and CFHT. The collaboration is grateful to the FRQNT, CFHT, the Canada Research Chair programme, the NSERC, the Swedish Research Council (Vetenskapsradet), the Swedish National Space Board (SNSB), the Royal Society and the Newton Fund via the award of a Royal Society-Newton Advanced Fellowship (NAF\R1\180403), FAPESC, CNPq, FAPESP (2014/11156-4), FAPESB (7916/2015), and CONACyT (CB2015-254132).

Introduction Bipolar disorder (BP) is one of the major causes of disability in the world. Epidemiological studies suggest that this disorder could be under-diagnosed owing to the difficulty in detecting hypomania episodes. The detection of present and past episodes of hypomania could help in the diagnosis and appropriate treatment of this disorder. The Hypomania Check List (HCL-32) is a questionnaire validated into Spanish and designed to detect past and present hypomania episodes in the psychiatric patient population. Materials and methods A total of 128 patients over 18 years old and diagnosed with type I bipolar (BP-I) disorder (n = 1), type II bipolar (BP-II) disorder (n = 30), major depression (MD) (n = 57), anxiety disorders (AD) (n = 15) were selected, along with a control group (C) (n = 25). The patients were diagnosed according to the diagnostic criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IVTR). Screening for hypomania episodes was carried out by applying the HCL-32 scale. Results The area under the ROC curve was 0.65 with a 95% confidence interval (CI) of 0.55–0.75. The chosen cut-off point of the HCL-32 was 15. The values for the sensitivity (Se), specificity (Sp), positive predictive values (PPV) and negative predictive values (NPV), and the prevalence (P) of hypomania episodes in the patients of the UP depression, for a cut-off point of 15 were: Se = 71.4%, 95% CI; 57.8, 85.1, Sp = 45.8%, 95% CI; 34.5–57.1, PPV = 43.75%, 95% CI; 32.25–55.25, NPV: 73.08%, 95% CI; 60.06–86.09 and P = 67.2%. Conclusions The HCL-32 is a very sensitive, but not very specific, screening tool. This could partly explain the high proportion of hypomania episodes detected in our sample. Unlike previous studies, our sample is heterogeneous (from different environments) and at a more severe and unstable clinical level. Future research should develop more specific measuring tools, and with greater external validation, for hypomania episodes.

Adaptable-diameter inductors are being implemented in domestic induction hobs in order to increase the range of suitable pot diameters and to achieve the better use of the rated power electronics. Such inductors are arranged by means of several concentric planar windings, usually up to three units, each one of them comprising several litz-wire turns. Currently, one resonant inverter is dedicated to supplying each winding. In this paper, a characterization of these inductors in terms of their impedance matrix is derived. The self-impedance of each winding and those caused by the coupling between them are analyzed. The contribution of this paper lies in the understanding and analysis of the coupling between concentric windings. Unlike transformers, where ideally the magnetic path consists of a lossless material, in domestic induction heating, the vessel is part of the flux path. Consequently, the off-diagonal terms of the impedance matrix have been generalized because they have a resistive component in addition to the classical mutual-inductance component. The analysis presented in this paper also includes the losses in the litz wires generated by the currents in each winding as well as the losses produced by the windings over their concentric neighbors.

Multiple-load and multiple-source systems are widely present in the current technology. These systems require controlling either the supplied voltage or power to several loads with different requirements simultaneously. As a consequence, the cost and size of the power stage may increase beyond the admissible limits for certain applications. Considering multiple-inductor loads, a novel series-resonant multiinverter topology is proposed to obtain a cost-effective and high-power density solution. The converter is based on a common inverter block and a resonant-load block. The performed analysis includes the description of the operation modes and the control strategy analysis. Domestic induction heating has been considered for application due to its special cost and size requirements, and the extensive inductor use. The proposed converter has been designed and validated experimentally through a prototype, which includes the power converter and the field-programmable gate array-based control architecture.

The efficiency of zero voltage switching half-bridge series resonant inverter can be decreased under certain load conditions due to the high switching frequencies required. The proposed variable frequency duty cycle (VFDC) control is intended to improve the efficiency in the medium and low output power levels because of the decreased switching frequencies. The study performed in this letter includes, in a first step, a theoretical analysis of power balance as a function of control parameters. In addition, restrictions due to snubber capacitors and deadtime, and variability of the loads have been considered. Afterward, an efficiency analysis has been carried out to determine the optimum operation point. Switching and conduction losses have been calculated to examine the overall efficiency improvement. VFDC strategy efficiency improvement is achieved by means of a switching-frequency reduction, mainly at low-medium power range, and with low-quality factor loads. Domestic induction heating application is suitable for the use of VFDC strategy due to its special load characteristics. For this reason, the simulation results have been validated using an induction heating inverter with a specially designed load.

Domestic induction cookers operation is based on a resonant inverter which supplies medium-frequency currents (20-100 kHz) to an inductor, which heats up the pan. The variable load that is inherent to this application requires the use of a reliable and load-adaptive control algorithm. In addition, a wide output power range is required to get a satisfactory user performance. In this paper, a control algorithm to cover the variety of loads and the output power range is proposed. The main design criteria are efficiency, power balance, acoustic noise, flicker emissions, and user performance. As a result of the analysis, frequency limit and power level limit algorithms are proposed based on square wave and pulse density modulations. These have been implemented in a field-programmable gate array, including output power feedback and mains-voltage zero-cross-detection circuitry. An experimental verification has been performed using a commercial induction heating inverter. This provides a convenient experimental test bench to analyze the viability of the proposed algorithm.

This paper presents the challenges encountered and the solutions adopted during the construction of a versatile voltage-fed high-frequency series-resonant half-bridge inverter module. It is used in the large-signal power generator of an inductive load characterization test-bench operating from 1 kHz up to 1.5 MHz and up to 7-kW output power for a variety of loads. Square wave operation of the module is established slightly above resonance under zero voltage switching conditions. Output power is controlled by means of a variable dc bus while resonant conditions are fixed by means of two adjustable capacitor banks. The control of every test-bench block and the triggering waveform generation is performed digitally with a field programmable gate array. Two prototype modules have been designed, constructed and evaluated for operation in half-bridge and full-bridge configurations showing rugged and stable operation under hazardous conditions such as voltage transients as high as dv/dt = 50 kV/mus at 1 MHz during the characterization of domestic induction heating loads.

This letter presents a powerful tool for the study of the performance of control strategies and consists of a versatile modulator capable of synthesizing triggering signals for various fixed-frequency and pulse width modulation controls based on a digital implementation. Among many other advantages, the approach provides a straightforward, flexible, and rapid means for prototyping because of its reprogramming capability and user-friendly interface. Field programmable gate array was chosen as the hardware platform because of the additional benefits it provides, such as high operating frequency and parallel processing capabilities. Several practical examples of its application demonstrate the utility of this approach

The formation of condensed phases by salts of heptyl viologen cation radical on mercury electrode in aqueous media under potentiostatic conditions is explained in light of a new mathematical model based on a desorption-nucleation mechanism. This initially assumes the nucleation process to be governed by the desorption of molecules previously adsorbed on the electrode surface. The potential subsequent incorporation of adsorbed molecules into the condensed 2D phase via surface reorientation (a reorientation-nucleation mechanism) is considered. The proposed model was successfully applied to the 2D nucleation of heptyl viologen in the presence of both strongly (bromide) and weakly (sulfate) adsorbed anions on a mercury electrode surface.

The mechanical behavior of porcine pericardium was analyzed to compare it with that of calf pericardium employed in valve leaflets for cardiac bioprostheses. Forty samples of pericardium were subjected to uniaxial tensile testing, 20 as controls and 20 exposed to loads increasing stepwise from 0.5 to 1.5 kg and to 3 kg, and thereafter to rupture, with a return to zero load between each new increment. Another 20 samples were used in biaxial tensile tests involving the application of loads increasing stepwise (to 0.5, 1.5, 3 and 5 kg) until rupture with a zero-load interval before each increment. The ultimate stresses were very similar, showing no statistically significant differences when compared in terms of type of assay, controls and study samples or region of pericardial tissue being tested. In the stepwise biaxial assays, the mean stresses at rupture were also very homogeneous. Using morphological and mechanical criteria for sample selection, it was possible to obtain mathematical fits for the stress/strain relationship, with excellent coefficients of determination. The relationship between the area under the stress/strain curve and the load applied or the strain observed was also studied in the biaxial assay as an equivalent to the cycles of hysteresis produced in the test. The increment in the area under the curve (the energy consumed) may be a good parameter for assessing the changes in the collagen fiber architecture of the pericardial tissue, changes that may help to detect early failure.

In aqueous media, the cation radical of heptyl viologen, HV +, forms a two-dimensional (2D) phase on a polycrystalline silver electrode. The phase results from the reduction of HV2+ molecules adsorbed on the electrode and consists of the cation radical salt and bromide as counterion; it is dissolved through gradual nucleation and growth of vacancies, which take place simultaneously with a Langmuir-type desorption process.

In DMSO containing Br- ions, the heptyl viologen cation radical (HV•+) can form two different types of two-dimensional (2D) phase on Hg. Thus, HV•+ can take a planar conformation relative to the su...

1. Patients with insulin-dependent diabetes mellitus are classified among the groups at risk for low vitamin status, and recent studies suggest that some degree of supplementation with antioxidants may be beneficial in helping to prevent certain long-term complications of diabetes mellitus. Our objective was to compare the status of the fat-soluble vitamins and antioxidant-related compounds in patients with well-defined insulin-dependent diabetes mellitus with that of their first-degree relatives, controlling seasonal and analytical variability as factors influencing the interpretation of the data. 2. Fifty-four patients with insulin-dependent diabetes mellitus, 214 non-diabetic, first-degree relatives (controls) and 236 unrelated controls were analysed for retinol, tocopherols (α and γ) and main carotenoids in serum (β-carotene, α-carotene, β-cryptoxanthin, lutein, zeaxanthin and lycopene) by means of a validated HPLC method. 3. Insulin-dependent diabetes mellitus was associated with lower retinol levels and higher levels of β-carotene, α-carotene and β-cryptoxanthin than sex-matched, first-degree relatives. α-Tocopherol, the α-tocopherol/cholesterol ratio, γ-tocopherol, lutein, zeaxanthin and lycopene showed no differences. Retinol and β-carotene were the variables most closely associated with diabetes. 4. Patients with insulin-dependent diabetes mellitus showed lower serum retinol status together with higher concentrations of provitamin-A carotenoids. Serum fat-soluble antioxidant levels were greater than or equal to those in controls. According to the serum status observed, individuals with diabetes do not require supplementation with α-tocopherol or carotenoids, although the need for retinol supplementation in patients with marginal serum levels should be evaluated.

The portal pressure response to propranolol varies significantly in individual patients with cirrhosis. At present, propranolol responders can be identified only by measuring the hepatic venous pressure gradient. The aims of this study were: 1) to investigate whether the noninvasive monitoring of portal blood flow by pulsed Doppler ultrasound and forearm blood flow by strain-gauge plethysmography can predict the hepatic venous pressure gradient response to propranolol in patients with cirrhosis, and 2) to analyze the factors that may influence this response.Hemodynamic measurements were undertaken in 80 patients with cirrhosis before and after receiving propranolol (0.15 mg/kg i.v., n = 60) or placebo (n = 20).No changes were observed in the placebo group. Propranolol lowered (p0.01) hepatic venous pressure gradient from 17.6 +/- 3.8 to 14.7 +/- 3.8 mmHg, portal blood flow from 1122 +/- 363 to 897 +/- 332 ml/min and forearm blood flow from 7.52 +/- 3.1 to 6.12 +/- 2.3 ml/min%. Changes in hepatic venous pressure gradient were correlated (p0.01) with those of portal blood flow (r = 0.82) and forearm blood flow (r = 0.54). The reduction in hepatic venous pressure gradient was20% in 23 patients ("responders"). The accuracy of portal Doppler flowmetry in identifying responders was higher than that of forearm plethysmography (88.3 vs. 68.3%, p0.05). Multivariate analysis proved that previous variceal bleeding was the only factor independently associated with a lack of response to propranolol (relative risk 3.42, 95% CI 1.5-7.4, p0.01). Hepatic venous pressure gradient reduction by propranolol was higher in non-bleeders than in bleeders (-19.9 +/- 9.4 vs. -11.3 +/- 8.6%, p0.01).Portal Doppler ultrasound can be used as a reliable surrogate indicator of the hepatic venous pressure gradient response to acute propranolol administration. In addition, our study indicates that this response is mainly influenced by previous variceal hemorrhage.

In aqueous media, heptyl viologen (HV2+) is reduced via a one-electron transfer to its cation radical (HV•+), the salt of which forms a two-dimensional (2D) phase on a mercury electrode. In this work, we studied the influence of temperature, the reagent concentration, and the type of anion present in the medium on the formation of this 2D phase. The critical temperature for the phase transition was found to be 80−85 °C. The experimental value obtained for the surface area occupied by the heptyl viologen molecule below 30 °C is about 70 A2; accordingly, the molecules must arrange themselves at an angle with the electrode surface. The anion concentration in a chloride medium was found to exert no appreciable effect on the 2D phase; on the other hand, increasing bromide ion concentrations in the medium shifted the nucleation peak to increasingly more negative potentials.

[ES] En este trabajo se presenta un estudio químico y estructural de las capas metálicas de Pt y TaSix utilizadas como puerta catalítica en sensores de gas de alta temperatura basados en dispositivos MOS de SiC. Para ello se han depositado capas de diferentes espesores sobre substratos de Si. Los resultados muestran que con la reducción del espesor de Pt y con un recocido se consigue aumentar la rugosidad de las capas de puerta, lo que debería aumentar la sensibilidad y la velocidad de respuesta de los dispositivos que las incorporasen. Otro efecto del recocido es la transformación química del material de la puerta que, para capas delgadas de Pt con TaSix, produce la transformación total Pt en Pt2Ta, lo que podría afectar a las características catalíticas de la puerta. Los primeros resultados eléctricos indican que, a pesar de que las capas de Pt empleadas son gruesas y compactas, los diodos MOS túnel de SiC son sensibles a los gases CO y NO2, aunque presentan una velocidad de respuesta bastante lenta., [EN] In this work the chemical and structural characterisation of metallic layers of Pt and TaSix, employed as catalytic gates in high temperature gas sensors based on MOS devices on SiC substrates, is presented. For the study layers of different thickness have been deposited on Si substrates. The results show that the roughness of the layers increases with the reduction of the thickness of Pt and with annealing, which should give rise to an increase in the sensitivity and response speed of the devices. Another consequence of the annealing is the chemical transformation of the gate’s materials that, for thin films of Pt with TaSix, produces the complete transformation of Pt into Pt2Ta, which might affect the catalytic properties of the gate. The first electrical results show that, even with thick and compact Pt layers, the SiC-based MOS tunnel diodes are sensitive to CO and NO2 gases, although the response time is relatively long. its response speed is too slow., Este trabajo ha sido financiado en parte por la Subdirección General de Proyectos de Investigación del Ministerio de Ciencia y Tecnología, a través del proyecto TIC2000-1403-C03.

Background Psoriatic arthritis (PsA) is a potentially destructive inflammatory chronic arthropathy, with a wide range of clinical manifestations. Currently, biological therapy (BT) is the second step of treatment after an inadequate response to conventional disease-modifying anti-inflammatory drugs. Objectives The goal of our study was to identify baseline characteristics of patients with PsA associated with the need for BT use during the follow-up. Methods This is a single-centre, case-control study. Unselected PsA patients diagnosed after December 31st, 1999 and fulfilling CASPAR classification criteria were included. Reviewing medical records identified epidemiological, clinical, analytical and imaging features. The main outcome was the need of BT during the follow-up. The local ethical committee authorized the study. Chi-square, Student t test, and Mann-Whitney U test were used to establish statistical significance in the univariate analysis. Logistic regression was used for the multivariate analysis. A p Results One hundred and fifty-nine patients were included (75 women and 84 men), with a mean age of 48 years. During the follow-up, 66 patients (41%) needed BT (BT+ patients). No significant differences in age, sex, race, presence of cardiovascular risk factors, smoking, alcohol consumption, initial joint pattern, presence of dactylitis, presence of onychopathy, HLA B27 positivity, presence of radiographic erosions, presence of axial radiographic involvement, mean C-reactive protein, or mean erythrocyte sedimentation rate were found in BT+ patients when compared with BT negative (BT−) patients. Twenty per cent of BT− patients had enthesitis at the beginning, compared with 39% of BT+ patients [Odds ratio 2.53 (CI 95%: 1.25–5.12); p=0.009]. Mean time from the onset of symptoms to the first appointment with a rheumatologist was significantly associated with the need for further use of BT (20 weeks in BT− patients versus 108 weeks in BT+ patients; p Conclusions In PsA patients, the initial presence of enthesitis is an independent risk factor associated with the need for biological therapy during the follow-up. Disclosure of Interest None declared

Background Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder that leads to an irreversible destruction of diarthrodial joints. Early diagnosis and treatment with disease-modifying antirheumatic drugs (DMARDs) are considered essential in order to achieve an optimal suppression of disease activity and prevent structural and functional deterioration. Biological therapy (BT) is the second-line treatment in case of inadequate response to DMARDs. BT has excellent safety and efficacy profiles. However, its economic burden is high. Objectives The goal of our study was to identify clinical, epidemiological and analytical characteristics, as well as the delay of diagnosis, DMARD treatment, and inflammatory activity, associated with the need to initiate BT in RA patients. Methods This is a single-center case-control study. We included patients who were diagnosed with RA from January 1, 2000, fulfilling the 2010 ACR/EULAR criteria. The main outcome (dependent variable) was the need for a first biological drug. The independent variables were time to diagnosis, time to treatment with the first DMARD, time to clinical remission, time to low activity, age, gender, number of swollen joints (NSJ) and tender joints (NTJ) at the time of diagnosis, positivity of RF and ACPA, CRP, ESR, radiologic erosions, smoking, body mass index, education level, and job status. The study was approved by the research ethical committee of our center. Descriptive statistics was used to present the results; chi-square test, Student t test, and Mann-Whitney U test were used to define statistical significance in the univariate analysis; and logistic regression for multivariate analysis. A P -value Results One hundred and thirty-nine patients were included (mean age 53 years; 82% women; 83% white; 82% RF+; 74% ACPA+). Sixty-one patients (44%) had received BT. The univariate analysis demonstrated significant association between the need for BT and NTJ (p Conclusions In RA patients, the number of tender joints at the time of diagnosis and the time to low disease activity and clinical remission are associated with the need for BT during the course of the disease. Disclosure of Interest None declared

Experimental evidence indicates that an increased production of nitric oxide could play a role in the peripheral vasodilation of portal hypertension. To test this hypothesis in humans, we studied basal serum NO(2-) + NO3- levels and the response of forearm resistance vessels to increasing concentrations of methacholine chloride, sodium nitroprusside, and phenylephrine infused into the brachial artery of 12 cirrhotic patients and 10 controls. Forearm vascular resistance (FVR) was calculated from mean arterial pressure and forearm blood flow (FBF). Cirrhotics showed higher NO(2-) + NO3- levels (P < 0.05), higher FBF (P < 0.01), and lower FVR (P < 0.01) than controls. The reduction of FVR in response to every dose of methacholine was greater in cirrhotics than in controls; this was significant (P < 0.05) at the 3 and 10 micrograms/min doses. This response to methacholine was not modified by blockade of vascular prostacyclin. The response to nitroprusside was similar in both groups. The increase in FVR in response to every dose of phenylephrine was significantly (P < 0.01) lower in cirrhotics than in controls. In cirrhotics, a significant correlation (r = -0.81, P < 0.01) was found between the FVR response to the highest doses of methacholine and phenylephrine. In conclusion, cirrhotic patients show an enhanced endothelium-mediated vasodilation, which suggests an increased synthesis of nitric oxide. This defect may mediate the peripheral vasodilation and hyporeactivity to vasopressors of these patients.

In an induction heating system the energy delivered into the work piece for heating purposes with respect to the self-heating of the windings is quantified by means of the induction efficiency. This parameter can be measured by using an energy balance, for example the ratio between the boiled water weight and the electrical energy supplied into the windings considering a period of time. In this paper an experimental setup for measurements of the induction efficiency in domestic systems is presented. In order to reduce errors in the electrical power measurements, which involve voltage and current signals at frequencies up to 100 kHz with harmonics, a method using differential measurements of the boiled water weight is proposed. Experimental results of the induction efficiency of a commercial induction system operated in real conditions are presented.

The tearing of the fibers of biomaterials employed in implants or bioprostheses leads to early the failure of these devices. The purpose of this study was to determine the force necessary to propagate a tear in a biological tissue, calf pericardium, when sutured. We analyzed the outcome of 230 trials. There was a loss of resistance to tearing in samples sutured edge-to-edge as compared to unsutured control samples. This loss was not observed when the suture was preceded by an intact or protective zone. The values corresponding to the tearing force for an overlapping suture, especially when sewn with Gore-Tex(R), were higher than those obtained in controls. This study confirms the deleterious effect of the edge-to-edge suture, which can be minimized by protecting the suture, and the excellent behavior of the overlapping suture.

Designing the converter for an induction cooker, the main difficult lies in the variability of the load, due to the wide range of vessels available in the market. Such issue is equivalent to the problem of identifying the vessel's properties. In this paper an identifying method of such properties is proposed with the objective of system-level simulation and design. The method is based on a combination of analytical electromagnetic calculations, and Fourier-series-based waveform synthesis.

Adaptable-diameter inductors are being implemented in domestic induction hobs in order to increase the range of suitable pot's diameters and to achieve a better use of the installed power electronics. Such inductors are arranged by means of several concentric planar windings, usually up to two or three units, each one of them comprising several Litz-wire turns. Normally, one resonant inverter is dedicated to supply each winding. In this paper, a model of these inductors in terms of their impedance matrix is derived. The self-impedance and the coupling between the windings are analyzed on the basis on the transformer analogy. The analysis also includes the losses in the Litz wires generated by the currents in each winding as well as the losses produced by the windings over its neighbors.

Multiple-inductor systems are widely present in the current technology. These systems require controlling either the supplied voltage or power to several loads with different requirements simultaneously. As a consequence, the cost and size of the power stage may increase beyond the admissible limits for certain applications. Considering multiple-inductor loads, a novel multiple-output series resonant inverter (MOSRI) topology is proposed to obtain a cost-effective and high-power-density solution. The converter is based on a common inverter block and a resonant-load block. The performed analysis includes the description of the operation modes and the control strategy analysis. Domestic induction heating has been considered for application due to its special cost and size requirements, and the extensive inductor use. The proposed converter has been designed and validated experimentally through a prototype, which includes the power converter and the FPGA-based control architecture.

Background ERCP can be associated with serious complications. Difficulty in common bile duct (CBD) cannulation is one of the main risk factors for post-ERCP pancreatitis. The double-guidewire technique (DGT) has been considered a promising alternative approach in difficult cannulation situations. Objective To compare the performance of DGT with the standard cannulation technique (SCT) in patients in whom CBD cannulation is difficult to perform. Design Multicenter randomized, controlled trial. Setting Six tertiary referral centers. Patients A total of 188 patients with difficult CBD cannulation defined by completion of 5 unsuccessful cannulation attempts were enrolled. Interventions Ninety-seven patients were assigned to the DGT group and 91 to the SCT group. Both techniques were compared for an extra 10 cannulation attempts. Main Outcome Measurements CBD cannulation rate, number of attempts required to cannulate, and ERCP-related complications. Results Successful CBD cannulation was achieved in 46 of 97 (47%) patients in the DGT group compared with 51 of 91 (56%) in the SCT group (OR 0.85; 95% CI, 0.64-1.12). The median number of attempts required for each group was 9 and 7, respectively ( P = .128). The incidence of post-ERCP pancreatitis was 17% in the DGT group and 8% in the SCT group (OR 2.13; 95% CI, 0.89-5.05). Limitations Reduced number of enrolled subjects and a lack of detailed information regarding the number and extent of pancreatic duct contrast injections. Conclusions In patients with difficult CBD cannulation, DGT was not superior to SCT in achieving CBD cannulation. DGT might be associated with a higher risk of post-ERCP pancreatitis. (This study has been registered in ClinicalTrials.gov with identifier NCT00270868.)

Traditionally the domestic induction heating load has been electrically modelled by means of the series connection of an energetic equivalent resistance and inductance. Due to the nonlinear nature of the load and the excitation dependence of these equivalent parameters, which are only valid for a given waveform, there exists a strong lack of accuracy in certain situations and applications. In case precise temporal waveform is required a more complex and complete model reproducing dynamic effects must be develop. In this paper a well-known topology for the frequency dependent modelling in the linear case is modified obtaining the Foster series nonlinear network (FSNL) which is able to include both nonlinear and frequency dependent effects providing a complete dynamic behavioural load model. Results are presented for a typical induction heating load which has been characterized using a large-signal and wide frequency (12 kW- 1.5 MHz) measurement testbech. Optimization procedure is explained and performance is tested in the time domain in order to validate the modelling approach.

A group of substances of molecular masses between 300 and 1500 Da have been found to be toxic metabolites in patients with uremia. We determined the concentration in serum of these molecules in the following groups of patients: two hemodialyzed groups (one with cuprophane and the other with polyacrylonitrile dialyzers), one group treated with continuous ambulatory peritoneal dialysis, one group of nondialyzed azotemic patients, and one control group of healthy persons. Ultrafiltrates of the subjects' sera were fractionated on Sephadex G-15 followed by ion-exchange chromatography. Eluates were monitored by absorbance at 254 and 206 nm. Partially characterized peaks P1 and P2, obtained by gel filtration, correlated with the concentration of creatinine in serum; their concentrations were significantly (P less than 0.01) larger in hemodialyzed groups than in peritoneal dialyzed or in nondialyzed azotemic patients. After ion-exchange chromatography, two peaks (P'5 and P'6) correlated with serum creatinine and also were larger in hemodialyzed patients than in the other groups. Apparently, adequate discrimination is obtained by gel-filtration analysis and further analysis by ion-exchange chromatography does not provide additional information in most of the affected patients.

The analysis of ascitic fluid has been complicated by several recently reported new tests. To simplify this assessment, we evaluated nine parameters prospectively and simultaneously in blood and ascitic fluid from 285 patients with ascites to determine which were the most reliable for immediate diagnosis of the etiology of the ascites and of its complications. Subjects were first divided into four groups: sterile cirrhotic ascites (n = 201), spontaneous bacterial peritonitis (n = 41), malignant ascites (n = 34), and miscellaneous ascites (n = 9). An ascitic fluid polymorphonuclear count greater than 500/microliters was the test with the greatest accuracy (96%) for the diagnosis of spontaneous bacterial peritonitis. Neither the most precise cutoff values for ascitic fluid pH (less than 7.32) and ascitic fluid lactate (greater than 32 mg/dl), nor their respective blood-ascitic fluid gradients (greater than 0.11 and less than -20 mg/dl) were more reliable indexes of spontaneous bacterial peritonitis, mainly due to the decreased ascitic fluid pH and increased ascitic fluid lactate observed in malignant ascites, tuberculous peritonitis, and pancreatic ascites. A blood-ascitic fluid albumin gradient less than 1.1 g/dl was the most accurate parameter for the diagnosis of malignant ascites (diagnostic efficacy, 93%). Therefore, the etiologic analysis of ascitic fluid might be simplified and the single practice of two tests, ascitic fluid polymorphonuclear cell count and blood-ascitic fluid albumin gradient, provides immediately useful information.

Current research topics in domestic induction heating field, such as the analytical description or the grey- box modelling of the impedance behaviour of the inductor- pot coupled system, require experimental measurements to be obtained in a variety of situations covering wideband frequency operation and output power conditions due to its nonlinear nature. Frequency values up to the MHz range and current levels as high as several tenths of amperes can be needed to get the required information to describe the operation in real-working conditions. While small-signal impedance measurements are easily achieved up to 1 MHz and above with commercial LCR meters, no commercial equipment provides the complete solution for the power, frequency and load quality factor ranges required under large-signal operation so a custom- made measurement testbench must be designed. The testbench design comprises the development of a specific hardware for load excitation and the definition of the characterization procedures to obtain accurate impedance measurements which are described in this paper using a high performance digital oscilloscope and standard power electronics probes.

Nowadays domestic induction cookers usually heat ferromagnetic pans. This technology is well known and it is successfully applied by many manufacturers. However, there are a number of non-ferromagnetic pans (made of aluminium, copper, copper-nickel, or stainless steel) that cannot be properly heated by this technology. In this paper, a modified half-bridge series resonant inverter topology that can heat ferromagnetic and non-ferromagnetic pans is presented. This inverter topology has two topological configurations with two operation modes: first-harmonic operation mode (FHOM) and third-harmonic operation mode (THOM). This paper presents these two operation modes and the design of the principal parts of the inverter. Finally, the experimental results obtained with a prototype of the resonant inverter are presented.

In this paper, a study of the Discontinuous current Mode (DM) control applied to a half-bridge series resonant inverter for domestic induction heating is presented. The proposed control is interesting for this application because it exhibits reduced switching losses and the output power control is linear with the switching frequency. Considering that the load is disconnected from the source during part of the switching period, with DM control. A time-domain analysis method is proposed to obtain the analytical expression of the output power, the capacitor voltage and load current. The validity of the analytical expression is checked through simulation. Finally, an experimental comparison of efficiency between traditional controls and the DM control is performed for the induction heating application. In the low power range the efficiency of DM control is higher than traditional schemes.

This paper presents the challenges encountered and the solutions adopted during the construction of a versatile high-frequency series-resonant half-bridge voltage-fed inverter module. It is being used as the large-signal generator for an inductive load characterization test-bench which permits to obtain measurements in a real working situation over a wide frequency and output power operating conditions for a variety of loads. Square wave operation is established slightly above resonance under Zero Voltage Switching conditions to acquire near sinusoidal current and low losses. Output power is controlled by means of a variable DC bus and resonant conditions are fixed for each operating frequency by means of two adjustable resonant capacitor banks. The control of every test-bench block and the triggering waveform generation is performed digitally by means of a Field Programmable Gate Array. The modular approach and the flexible control implementation enable the utilization of several modules in parallel connection or full-bridge configuration widening the possibilities of load excitation. Final prototype covering the required operation range has been designed, and two modules have been constructed and evaluated for operation in half-bridge and full-bridge configurations showing rugged and stable operation during characterization of induction heating loads.

Current research topics in the field of domestic induction heating entail analytical study of inductor-pot coupling behavior which must be verified with experimental results. Small-signal measurements are easily achieved up to 1 MHz with commercial LCR meters. On the other hand, large-signal experimentation requires a custom made measurement test bench. Whatever the approach selected to design this system, the instrumentation will be divided into a signal generator, a data acquisition block and a post-processing method for model parameter extraction. In order to separate influence of main factors determining load electrical parameter values a good solution could be sinusoidal current excitation with selectable frequency and amplitude. The scheme proposed is the utilization of a high frequency resonant half-bridge inverter operating slightly above resonance under Zero Voltage Switching conditions to acquire near sinusoidal current. Output power control is carried out through of a variable DC bus and resonant conditions are fixed by means of an adjustable resonant capacitor. This paper enumerates the design challenges that such inverter involves in this application and which are the solutions adopted. Final prototype covering the required operation range has been designed, constructed and evaluated up to 1.5 MHz for a given active power of 3.5 kW at resonance with power capability of 16.8 kVA at Megahertz frequencies.

Domestic induction cookers can have several heating areas, hence multiple-output topologies are commonly used. One of these multiple-output topologies is the double series-resonant half-bridge inverter. An upgrading of this topology is proposed. This upgrading consists of adding a relay to allow connecting the capacitor tanks in parallel. The aim of this upgrading is to increase the efficiency through the reduction of the device currents. The proposed upgrading topology has been tested by means of a prototype.

The mechanical behavior of porcine pericardium was analyzed to compare it with that of calf pericardium employed in valve leaflets for cardiac bioprostheses. Forty samples of pericardium were subjected to uniaxial tensile testing, 20 as controls and 20 exposed to loads increasing stepwise from 0.5 to 1.5 kg and to 3 kg, and thereafter to rupture, with a return to zero load between each new increment. Another 20 samples were used in biaxial tensile tests involving the application of loads increasing stepwise (to 0.5, 1.5, 3 and 5 kg) until rupture with a zero-load interval before each increment. The ultimate stresses were very similar, showing no statistically significant differences when compared in terms of type of assay, controls and study samples or region of pericardial tissue being tested. In the stepwise biaxial assays, the mean stresses at rupture were also very homogeneous. Using morphological and mechanical criteria for sample selection, it was possible to obtain mathematical fits for the stress/strain relationship, with excellent coefficients of determination. The relationship between the area under the stress/strain curve and the load applied or the strain observed was also studied in the biaxial assay as an equivalent to the cycles of hysteresis produced in the test. The increment in the area under the curve (the energy consumed) may be a good parameter for assessing the changes in the collagen fiber architecture of the pericardial tissue, changes that may help to detect early failure.

The authors analyzed the mechanical behavior of the calf pericardium employed in the construction of valve leaflets for cardiac bioprostheses. Forty samples of pericardium were subjected to uniaxial tensile testing, 20 as controls and 20 exposed to loads increasing stepwise until rupture, with a return to zero load between each new increment. Another 20 samples were used similarly in biaxial tensile tests involving loads increasing stepwise until rupture, again returning to zero load between steps. The ultimate stresses in the uniaxial study were very similar and were not influenced by the region of pericardial tissue being tested or the increments in load to which the tissue was exposed. The mean stresses at rupture in the stepwise biaxial assays were significantly greater (p0.01). Using morphological and mechanical criteria for sample selection, it was possible to obtain mathematical fits for the stress/strain relationship in both types of assays, with excellent coefficients of determination (R (2)0.90). In uniaxial tests in which the selection criteria were not applied, the correlation improved as the load increased, a phenomenon that did not occur in the biaxial studies. The values varied throughout the different cycles, adopting exponential forms when the strain was greatest. These variations, which demonstrate that the increase in the energy consumed is a function of the stress applied and of the strain produced, should be good parameters for assessing the changes in the collagen fiber architecture of pericardial tissue subjected to cyclic stress, and may help to detect early failure.

The screening, diagnosis and evaluation of diseases of the ureter depend almost entirely on radiological examinations. Only the definite diagnosis is obtained, in some cases by biopsy, endoscopic techniques and sometimes after surgical excision and pathological examination of the lesion.

Cataract is an important health problem that increase with age, causes decreased visual acuity and constitute a major cause of disability in the elderly. Epidemiological studies have shown that elevated serum levels and / or intake of several antioxidants, such as carotenoids, vitamin E and ascorbic acid, are associated with a diminished risk for cataracts.To assess the serum fat-soluble antioxidant status in patients with cataracts and its relationship with visual function.One hundred thirty eight patients with senile cataracts, classified according to visual acuity, and 110 age and sex-matched controls were studied for individual carotenoids and tocopherols in serum by a quality-controlled HPLC method. One-way ANOVA analysis and logistic regression analysis were applied.Higher serum levels of lutein and zeaxanthin were associated as risk factors for cataract while b-cryptoxanthin and g-tocopherol appeared as protective variables. Higher levels of zeaxanthin and lower concentrations of b-cryptoxanthin were associated with cataracts in people61y whereas only lower levels of g-tocopherol were shown in subjects61y. No significant correlations (adjusted for sex and age) were found between visual acuity and serum concentrations of carotenoids or tocopherols.Although the relation between carotenoids and cataracts is biologically plausible, serum carotenoid levels are highly dependent on dietary intake and thus may not be clinically relevant biomakers for cataracts risk.

Transplants of adrenal medulla (AM) and fetal ventral mesencephalon (FVM) are currently being tested as therapeutic alternatives in patients with Parkinson's disease (PD). At the Clínica Puerta de Hierro in Madrid, a controlled clinical trial is underway to establish which donor tissue, if any, is the best for open surgical implantation in patients with PD.Since 1987, varying degrees of clinical improvement have been achieved in Grade IV and V parkinsonian patients by implanting perfused AM and FVM into the right caudate nucleus. To investigate further whether implantation of different types of donor tissues results in qualitatively and quantitatively different degrees of recovery, four patients with Grade IV or V PD received implants of pre-coincubated autologous AM and intercostal nerve in the caudate nucleus. Four nonsurgically treated patients served as a control group. Three years posttransplantation, longer on phases (46.2%+/-10.4% of the day presurgery to 87.5%+/-10.4% of the day 36 months postsurgery) and improved symptoms in on and off phases persist in all four cases, with reduced dyskinesias (67.1%+/-9.2% of the day in on phases presurgery to 17%+/-13.8% of the day in on phases 36 months postsurgery). Progress appears to be stepwise, starting within weeks of tranplantation and becoming clinically significant in the 2nd and 3rd months (similar to our AM- and sooner than in our FVM-implanted patients), followed by a period of stability and, after a second wave of improvement 12 to 18 months posttransplantation (similar to FVM implants), has continued (87.5+/-7 points presurgery to 46+/-5.6 points 36 months postsurgery). In the experimental group, doses of levodopa have been reduced by more than 60% and dopamine agonist use has not resumed. In contrast, there have been no significant clinical changes in the control group.Implantation of tissue other than fetal tissue can promote a long-term improvement in the clinical symptomatology of seriously disabled parkinsonian patients. This finding is supported by the autopsy report of a patient with PD who had undergone grafting of AM plus peripheral nerve in which it was demonstrated that a large number of tyrosine hydroxylase-positive cells survive 1 year after implantation. In addition, there was a dense network of host dopaminergic fibers around the graft.

Hypergammaglobulinemia is a well-known feature of liver cirrhosis, but studies on serum IgE in this setting are limited. The present study evaluates serum IgE concentration in a group of cirrhotic patients and examines their relationship with aetiological, clinical and analytical parameters (including liver function tests and hepatic phagocytic activity). The presence of specific IgE against common dietary antigens was also investigated. Total serum IgE was determined by enzyme immunoassay (EIA) in 52 cirrhotics (27 alcoholic and 25 non-alcoholic, including eight virus B and seven virus C-related cirrhosis, three primary biliary cirrhosis, three cryptogenic, three haemochromatosis and one Wilson's disease) and 34 healthy subjects (used as controls). Serum IgE (IU/ml) in controls was not significantly different from that of cirrhotic patients (median 42, range 2-726 vs median 86, range 2-1000, respectively) (P = NS). However, serum IgE among alcoholics (median 199, range 19-1000) was higher than that of controls (P0.001), virus B-related cirrhotics (median 25, range 3-1000) (P0.05), virus C-related cirrhotics (median 47, range 2-170) (P0.05), or non-alcoholic cirrhotics as a whole (median 23, range 2-1000) (P0.01). High IgE levels (or = 170 IU/ml) were detected in 55.5% of alcoholics compared with only 12% of non-alcoholic cirrhotics (P0.01). Moreover, IgE levels were very high (1000 IU/ml) in six patients of the alcoholic group (22.2%) compared with only one non-alcoholic patient (4%).(ABSTRACT TRUNCATED AT 250 WORDS)