Syngas Production in a 1.5 kWth Biomass Chemical Looping Gasification Unit Using Fe and Mn Ores as the Oxygen Carrier.

Biomass chemical looping gasification (BCLG) uses lattice oxygen from an oxygen carrier instead of gaseous oxygen for high-quality syngas production without CO2 emissions. In this work, the effect of the main operating variables, such as oxygen/biomass ratio (λ), gasification temperature, and steam/biomass ratio (S/B), was investigated using two low-cost materials: a Fe ore and a Mn ore. Oxygen fed to the air reactor for oxidation was used as an effective method for controlling the amount of lattice oxygen used for syngas production. The main variable that affected the process performance and the syngas quality was λ, while the fuel reactor temperature and the S/B ratio had a minor effect. Small performance differences found between the ores can be attributed to different degrees of CH4 and light hydrocarbons reforming in the process. The CO2 content in the syngas was high (40 -43%) under autothermal conditions because the gasification reactions required the heat to be generated by combustion. CH4 contents of around 10% were found in syngas, coming from the unburned or unreformed volatiles. Syngas yields around 0.60 Nm3/kg of dry biomass were found for both ores. Additionally, high biomass conversions (X b > 94%) and carbon conversion efficiencies (ηcc > 95%) were obtained in all cases, showing the capability of the process of avoiding CO2 emissions to the atmosphere. No agglomeration was found in the bed during the BCLG process, although attrition rates were high, leading to lifetimes of 160 and 300 h for the manganese and iron ores, respectively. Migration of Fe or Mn to the external part of the particle, generating a metal concentrated shell, was observed. Its detachment was responsible for the decrease in the oxygen transport capacity (R OC) of the material with the operating time and the reduced lifetime. The results obtained here allowed the iron ore to be considered as an oxygen carrier suitable for the BCLG process.

Structure and electrochemical properties of carbon nanostructures derived from nickel(II) and iron(II) phthalocyanines.

Mesoporous carbons containing up to 3.6 at.% N and 4.4 at.% O and exhibiting graphitic character have been prepared from Ni(II) and Fe(II) phthalocyanines by direct pyrolysis or by HTC + pyrolysis, and subsequently applied as supercapacitor materials. No mesoporous templates or doping post-treatments were used, and the catalytic effect of Ni(II) and Fe(II), naturally present in the precursor molecules, allowed obtaining graphitic carbons at temperatures ≤ 900 °C. Metals were encapsulated in the core of onion-like structures with no contact with the electrolyte, so that electrodes were prevented from degradation during device operation. The materials exhibited high rate capabilities up to 1 V s-1, higher interfacial capacitances than a wide variety of materials possessing higher surface areas, and high capacitance retentions up to 99% at 5 A g-1 current density throughout 10 000 charge-discharge cycles. The electrochemical performances of the phthalocyanine-derived carbons are due to their graphitic character and to the pseudocapacitance contribution of the surface groups through Faradaic reactions. This work opens a new way to obtain carbon materials from a great family of metal phthalocyanines, since the central metal and the radicals of the latter can be varied to tune the carbon properties for specific applications.

Viabilidad del desfibrilador automático implantable subcutáneo en un paciente con pectum excavatum / Feasibility of a subcutaneous implantable cardioverter-defibrillator in a patient with pectus excavatum

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Nanostructured tin oxide materials for the sub-ppm detection of indoor formaldehyde pollution.

Interesting sensing performances of indoor formaldehyde pollution were obtained when small amounts of zinc were introduced in tin oxides. Nanostructured Sn oxide-based porous materials doped with Zn or not, were synthesized using hydrothermal routes. The physicochemical properties of the as-prepared metal-oxide materials were characterized using nitrogen adsorption, X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Gas sensors were prepared using the aforementioned tin oxide materials and they exhibited a high sensitivity to formaldehyde at 230 °C, as well as a good repeatability over the time. Their limit of formaldehyde detection was as low as 8 ppb in dry air and 50 ppb in air with 60% RH at 25 °C. These results were much better that those reported in the open literature and they were attributed to both higher area BET, around 180 m2/g, and smaller crystallite size, 3.1 nm.

Effects of ultrasound on anxiety and psychosocial adaptation to pregnancy.

Ultrasound is a common medical care procedure during pregnancy which has psychological implications. Research has found that it reduces the mother's level of anxiety, but there is not enough literature on the effects of the ultrasound in relation to the trimester it is done (first, second, and third) and the effects on the psychosocial adaptation to pregnancy. The purpose of this study was to investigate the effects of the ultrasound in the first, second, and third trimester on anxiety and variables related to psychosocial adaptation to pregnancy. A pre-post intervention design was used. Participants were 111 pregnant women attending a prenatal diagnosis ultrasound scan procedure, State-Trait Anxiety Inventory (STAI), and Prenatal Self-Evaluation Questionnaire (PSEQ) were used to measure anxiety and psychosocial adaptation to pregnancy, respectively. Previous history was obtained through an interview. Results indicated that anxiety diminished after the ultrasound regardless of the trimester in which the ultrasound took place. However, first trimester ultrasound showed an additional benefit favoring the mother's psychosocial adaptation to pregnancy, identification with the motherhood role, and the quality of the relationship with the partner. These findings suggest that in addition to the medical value of the ultrasound, it also has an important psychological value that has to be considered in order to guarantee an integral care of the pregnant women, especially in the first trimester.

Long-term prognosis of patients with life-threatening ventricular arrhythmias induced by coronary artery spasm.

Aims: Coronary artery spasm (CAS) is associated with ventricular arrhythmias (VA). Much controversy remains regarding the best therapeutic interventions for this specific patient subset. We aimed to evaluate the clinical outcomes of patients with a history of life-threatening VA due to CAS with various medical interventions, as well as the need for ICD placement in the setting of optimal medical therapy. Methods and results: A multicentre European retrospective survey of patients with VA in the setting of CAS was aggregated and relevant clinical and demographic data was analysed. Forty-nine appropriate patients were identified: 43 (87.8%) presented with VF and 6 (12.2%) with rapid VT. ICD implantation was performed in 44 (89.8%). During follow-up [59 (17-117) months], appropriate ICD shocks were documented in 12. In 8/12 (66.6%) no more ICD therapies were recorded after optimizing calcium channel blocker (CCB) therapy. SCD occurred in one patient without ICD. Treatment with beta-blockers was predictive of appropriate device discharge. Conversely, non-dihydropyridine CCB therapy was significantly protective against VAs. Conclusion: Patients with life-threatening VAs secondary to CAS are at particularly high-risk for recurrence, especially when insufficient medical therapy is administered. Non-dihydropyridine CCBs are capable of suppressing episodes, whereas beta-blocker treatment is predictive of VAs. Ultimately, in spite of medical intervention, some patients exhibited arrhythmogenic events in the long-term, suggesting that ICD implantation may still be indicated for all.

Outcome of patients with syncope beyond the implantable loop recorder.

AIMS: The implantation of an implantable loop recorder (ILR) leads to the diagnosis in about 35% of patients with syncope of unknown origin. Information on outcome of patients in whom a diagnosis is not reached during the lifetime of the device is scarce. The aim of our study is to determine the outcome of these patients in terms of syncope recurrence and survival. METHODS AND RESULTS: An ILR was implanted to 97 patients with syncope of unknown origin. Patients were classified in groups A and B depending on their high or low risk, respectively, of having arrhythmic syncope. Diagnosis had not been reached in 60 patients (62%) when the ILR battery reached end operational life. Five patients were lost to follow up. During a median follow-up of 48 months after ILR explantation (interquartile range 36-56), 22 patients (40%) had recurrence of syncope (32% in group A vs. 48% in group B, P = 0.3). Syncopes with no neurally mediated profile were more frequent in group A (18 vs. 0%, P = 0.05) and neurally mediated profile syncopes were more frequent in group B (44 vs. 11%, P = 0.007). Five patients died, four of them in group A and 1 in group B (P = 0.4). No sudden or cardiac deaths were detected during follow-up. All deaths were due to non-cardiac causes. CONCLUSION: Recurrent syncope is common in patients in whom a diagnosis is not established after the full battery life of an ILR. The prognosis of these patients seems to be good, without observed sudden or cardiac death.

Factores predictivos de infección por el virus de la gripe H1N1 2009 en pacientes con síndrome gripal / Predictive factors of 2009 H1N1 virus infection in patients with influenza syndrome

Introducción: La técnica de reacción en cadena de la polimerasa en frotis nasofaríngeo es uno de los mejores métodos para la detección de virus gripales. El objetivo de este estudio es conocer el porcentaje de frotis nasofaríngeos positivos durante la pandemia de gripe de 2009 y determinar si existe algún factor predictor de positividad para el virus H1N1 2009. Métodos: Estudio retrospectivo de todos los pacientes que consultaron en Urgencias por síndrome gripal entre el 15 de julio y el 15 de diciembre de 2009 a los que se realizó un frotis nasofaríngeo. Se identificaron aquellos casos en los que el frotis estaba correctamente solicitado. Se dividieron en dos grupos según la positividad para el virus H1N1 2009. Resultados: Se realizó un frotis nasofaríngeo a 362 pacientes. En 87 casos estaba incorrectamente indicado. De los 275 restantes, fue positivo en 141. Los pacientes con frotis positivo eran más jóvenes (36,1(15) años vs 42,3(18); p=0,002), tenían menor recuento de leucocitos, neutrófilos y linfocitos, menor valor de proteína C reactiva (5,15(5) vs 10,5(12); p<0,001) y menor incidencia de infiltrados radiológicos (20,5% vs 33%; p=0,036). La regresión logística identificó la edad, una proteína C reactiva baja y un recuento linfocitario bajo como factores independientes de infección por el virus H1N1 2009. Conclusiones: En pacientes con síndrome gripal, el porcentaje de positividades del frotis para detectar H1N1 2009 se sitúa en el 50%. La edad, los niveles de proteína C reactiva y el recuento linfocitario son factores independientes para predecir el resultado(AU)

Introduction: Polymerase chain reaction (PCR) testing is one of the better techniques for viral detection in nasopharyngeal swabs. The objective of this study was to assess the percentage of positive swabs and to determine whether there were differences according to PCR positivity. Material and Methods: A retrospective study of 362 patients with flu syndrome attended at the Emergency Department between July 15 and December 15, 2009, in whom PCR of nasopharyngeal swabs for the detection of H1N1 2009 influenza virus was performed. Those cases in which swab testing was adequately requested were identified, and patients were divided into two groups according to positive or negative results for H1N1 2009 influenza virus. Results: Nasopharyngeal swab was inadequately ordered in 87. In the remaining 275 patients, PCR was positive in 141. Patients with positive nasopharyngeal swabs were younger (mean [SD] age 36.1 [15] vs 42.3 [18] years, P = 0.002), had lower white blood cell, neutrophil and lymphocyte counts, lower serum concentrations of C-reactive protein (5.15 [5] vs 10.5 [12] mg/dL, P = 0.036) and lower incidence of radiological infiltrates (20.5% vs 33%, P = 0.036). In the logistic regression analysis, age, serum C-reactive protein levels, and lymphocyte count were independently associated with a positive nasopharyngeal swab. Conclusions:About 50% of patients with flu syndrome had positive nasopharyngeal swabs for H1N1 2009 influenza virus. Age, C-reactive protein, and lymphocyte count were independent predictors of positivity(AU)

Predictor factors for the development of arterial hypertension following heart transplantation.

INTRODUCTION: Up to 95% of the patients with heart transplantation (HT) suffer from arterial hypertension (AHT). The development of de novo AHT after HT has not been greatly studied. AIM: To identify the predictor variables for the development of de novo AHT after HT. MATERIALS AND METHODS: We retrospectively studied 253 patients with HT and who did not previously have AHT. We excluded cases of early mortality, re-transplants and combined transplants. We considered AHT as the constant need to take anti-hypertensive drugs to maintain blood pressure < 140/90 mmHg. We studied all the variables relating to recipient, donor, surgical procedure, immunosuppression and follow-up. The statistics used were the Student's t-test, chi-square statistic and a logistic regression analysis. RESULTS: Of the 253 patients, 109 (43%) developed AHT. The variables associated with more prevalent AHT were male recipient/donor, idiopathic dilated cardiomyopathy (IDCM) as cause of HT, having been a smoker as well as renal deterioration (RD) and hypercholesterolemia after HT. The multivariate analysis found smoking prior to the HT and hypercholesterolemia during follow-up as independent risk factors and urgent HT as a protective variable. CONCLUSIONS: AHT after HT is frequent. The variables associated in our population were smoking before HT, male recipient/donor, IDCM prior to HT and hypercholesterolemia and RD after HT.

Hepatitis colestásica fibrosante relacionada con el virus de la hepatitis C tras el trasplante cardíaco / VHC-related fibrosing cholestatic hepatitis after cardiac transplantation

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