Evaluation of Sputtering Processes in Strontium Iridate Thin Films.

The growth of epitaxial thin films from the Ruddlesden-Popper series of strontium iridates by magnetron sputtering is analyzed. It was found that, even using a non-stoichiometric target, the films formed under various conditions were consistently of the perovskite-like n = ∞ SrIrO3 phase, with no evidence of other RP series phases. A detailed inspection of the temperature-oxygen phase diagram underscored that kinetics mechanisms prevail over thermodynamics considerations. The analysis of the angular distribution of sputtered iridium and strontium species indicated clearly different spatial distribution patterns. Additionally, significant backsputtering was detected at elevated temperatures. Thus, it is assumed that the interplay between these two kinetic phenomena is at the origin of the preferential nucleation of the SrIrO3 phase. In addition, strategies for controlling cation stoichiometry off-axis have also been explored. Finally, the long-term stability of the films has been demonstrated.

Spin-to-Charge Conversion in All-Oxide La2/3Sr1/3MnO3/SrIrO3 Heterostructures.

Spin injection and spin-charge conversion processes in all-oxide La2/3Sr1/3MnO3/SrIrO3 (LSMO/SIO) heterostructures with different SIO layer thickness and interfacial features have been studied. Ferromagnetic resonance (FMR) technique has been used to generate pure spin currents by spin pumping (SP) in ferromagnetic (FM) half-metallic LSMO. The change of the resonance linewidth in bare LSMO layers and LSMO/SIO heterostructures suggests a successful spin injection into the SIO layers. However, low values of the spin mixing conductance, compared to more traditional permalloy (Py)/Pt or yttrium iron garnet (YIG)/Pt systems, are found. A thorough analysis of the interfaces by high-resolution scanning transmission electron microscopy (HR-STEM) imaging suggests that they are structurally clean and atomic sharp, but a compositional analysis by energy-dispersive X-ray spectroscopy (EDS) reveals the interdiffusion of La, Ir, and Mn atomic species in the first atomic layers close to the interface. Inverse spin Hall effect (ISHE) measurements evidence that interfacial features play a very relevant role in controlling the effectiveness of the spin injection process and low transversal ISHE voltage signals are detected. In addition, it is found that larger voltage signals are detected for the lowest SIO layer thickness highlighting the role of the spin diffusion length (λsd)/SIO layer thickness ratio. The values of ISHE voltage are rather low but allow us to determine the spin Hall angle of SIO (θSH ≈ 1.12% at T = 250 K), which is remarkably similar to that obtained for the well-known Py/Pt system, therefore suggesting that SIO could be a promising spin-Hall material.

X-ray Absorption Spectroscopy Study of Thickness Effects on the Structural and Magnetic Properties of Pr2-δNi1-xMn1+xO6-y Double Perovskite Thin Films.

In this work, we report a systematic study of the influence of film thickness on the structural and magnetic properties of epitaxial thin films of Pr2-δNi1-xMn1+xO6-y (PNMO) double perovskite grown on top of two different (001)-SrTiO3 and (001)-LaAlO3 substrates by RF magnetron sputtering. A strong dependence of the structural and magnetic properties on the film thickness is found. The ferromagnetic transition temperature (TC) and saturation magnetization (Ms) are found to decrease when reducing the film thickness. In our case, the thinnest films show a loss of ferromagnetism at the film-substrate interface. In addition, the electronic structure of some characteristic PNMO samples is deeply analyzed using X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) measurements and compared with theoretical simulations. Our results show that the oxidation states of Ni and Mn ions are stabilized as Ni2+ and Mn4+, thus the ferromagnetism is mainly due to Ni2+-O-Mn4+ superexchange interactions, even in samples with poor ferromagnetic properties. XMCD results also make evident large variations on the spin and orbital contributions to the magnetic moment as the film's thickness decreases.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma / Análisis de los potenciales factores de riesgo en la supervivencia de pacientes con liposarcoma retroperitoneal primario

Introduction: The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma.Methods: The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019.Results: The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02–19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50–8.86). Conclusion: Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival. (AU)

Introducción: El presente trabajo es un estudio observacional de una serie de variables relacionadas con la supervivencia global y la supervivencia libre de enfermedad en pacientes diagnosticados de liposarcoma primario. Métodos: Este es un estudio prospectivo con recolección de datos retrolectiva que incluye a todos los pacientes con liposarcoma primario remitidos al Hospital Son Espases en Palma de Mallorca, desde enero de 1990 hasta diciembre de 2019. Resultados: El estudio incluye 50 pacientes y la cirugía compartimental se realizó en 18 (36%) de ellos. La supervivencia global media de la muestra fue de 15,57 años (IC 95% 12,02-19,12) y la supervivencia libre de enfermedad media fue de 6,70 años (IC 95% 4,50-8,86). Conclusiones: La cirugía compartimental no ha mostrado beneficios en términos de supervivencia general y supervivencia libre de enfermedad. La clasificación ASA (≥3) predice un mal pronóstico tanto en la supervivencia global como en la supervivencia libre de enfermedad. La resección con márgenes libres, descrita en los resultados patológicos y definida en este trabajo como R0, muestra una mejor supervivencia libre de enfermedad. (AU)

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma.

INTRODUCTION: The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma. METHODS: The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019. RESULTS: The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86). CONCLUSION: Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

Optimization of the Growth Process of Double Perovskite Pr2-δNi1-xMn1+xO6-y Epitaxial Thin Films by RF Sputtering.

Epitaxial thin films of Pr2-δNi1-xMn1+xO6-y (PNMO) double perovskite were grown on (001)-oriented SrTiO3 substrates by RF magnetron sputtering. The influence of the growth parameters (oxygen pressure, substrate temperature, and annealing treatments) on the structural, magnetic and transport properties, and stoichiometry of the films was thoroughly investigated. It is found that high-quality epitaxial, insulating, and ferromagnetic PNMO thin films can only be obtained in a narrow deposition parameter window. It is shown that a careful selection of the growth conditions allows for obtaining a high degree of Ni/Mn cation ordering, which is reflected in the values of the Curie temperature, TC, and saturation magnetization, MS, which are very close to those of bulk material.

Suppression of spin rectification effects in spin pumping experiments.

Spin pumping (SP) is a well-established method to generate pure spin currents allowing efficient spin injection into metals and semiconductors avoiding the problem of impedance mismatch. However, to disentangle pure spin currents from parasitic effects due to spin rectification effects (SRE) is a difficult task that is seriously hampering further developments. Here we propose a simple method that allows suppressing SRE contribution to inverse spin Hall effect (ISHE) voltage signal avoiding long and tedious angle-dependent measurements. We show an experimental study in the well-known Py/Pt system by using a coplanar waveguide (CPW). Results obtained demonstrate that the sign and size of the measured transverse voltage signal depends on the width of the sample along the CPW active line. A progressive reduction of this width evidences that SRE contribution to the measured transverse voltage signal becomes negligibly small for sample width below 200 µm. A numerical solution of the Maxwell equations in the CPW-sample setup, by using the Landau-Lifshitz equation with the Gilbert damping term (LLG) as the constitutive equation of the media, and with the proper set of boundary conditions, confirms the obtained experimental results.

Long-term comparative study on open versus laparoscopic biliopancreatic diversion.

BACKGROUND: To date, bariatric surgery has been proposed as the most effective treatment to resolve morbid obesity, a multifactorial chronic disease with an epidemic and increasing tendency. The purpose of this study was to determinate the impact of the laparoscopy on weight loss parameters in morbid obese patients who underwent surgery according to Scopinaro's biliopancreatic diversion (BPD) and evaluate early and late complications related to the open and laparoscopic approach of this technique. MATERIALS AND METHODS: This is a longitudinal retrospective study in consecutive patients undergoing BPD due to morbid obesity between 1999 and 2015. From 2006 the laparoscopic technique was introduced in our group for obesity surgery. In both approaches, open and laparoscopic surgery, the procedure performed consists of a proximal gastric section with a long Roux-en-Y reconstruction. The following variables were assessed in the two groups: intervention duration (min), estimated blood loss (mL), conversions to open approach (%), preoperative stay, postoperative and global stay (days). Complications were divided into early and late postoperative complications. The early surgical complications were catalogued according to the Clavien-Dindo classification. RESULTS: Two hundred seventy-seven patients were consecutively enrolled and divided in two groups: open BPD and laparoscopic BPD. There were no significant differences in the comparison of the two groups and the mean age was 43.9 years (19-60) with a mean BMI of 52.5 kg/m2. A statistically significant reduction was observed in favor of the laparoscopic group with respect to the reduction in hospital stay and in the incidence of incisional hernia as a late complication. No statistically significant difference were found with respect to early postoperative complications. CONCLUSIONS: Laparoscopic BPD is a safe technique that allows a shorter hospital stay compared to open surgery and that allows a drastic reduction in the incidence of incisional hernias.

Analysis of potential risk factors in the survival of patients with primary retroperitoneal liposarcoma.

INTRODUCTION: The present work is an observational study of a series of variables regarding overall survival and disease-free survival in patients diagnosed with primary liposarcoma. METHODS: The study is prospective with retrolective data collection that includes all patients with primary liposarcoma referred to Hospital Son Espases University Hospital, Palma de Mallorca, Spain from January 1990 to December 2019. RESULTS: The study includes 50 patients and the compartment surgery was performed in 18 patients (36%) of cases. The mean overall survival of the sample was 15.57 years (95% CI: 12.02-19.12) and the mean disease-free survival was 6.70 years (95% CI: 4.50-8.86). CONCLUSION: Compartment surgery has not shown benefits in terms of overall survival and disease-free survival. The ASA classification (≥3) predicts a poor prognosis in both overall survival and disease-free survival. Resection with free margins, described on the pathological results and defined in this work as R0, show better disease-free survival.

Formation of Nickel Oxide Nanocuboids in Ferromagnetic La2Ni1-xMn1+xO6.

The control of the spontaneous formation of nanostructures at the surface of thin films is of strong interest in many different fields, from catalysts to microelectronics, because surface and interfacial properties may be substantially enhanced. Here, we analyze the formation of nickel oxide nanocuboids on top of La2Ni1-xMn1+xO6 double perovskite ferromagnetic thin films, epitaxially grown on SrTiO3 (001) substrates by radio-frequency (RF) magnetron sputtering. We show that, by annealing the films at high temperature under high oxygen partial pressure, the spontaneous segregation of nanocuboids is enhanced. The evolution of the structural and magnetic properties of the films is studied as a function of the annealing treatments at different temperatures. It is shown that the formation of NiOx nanocuboids leads to a nanostructured film surface with regions of locally different electrical transport characteristics.

Adenocarcinoma sobre quiste de duplicación yeyunal / Adenocarcinoma over a jejunal duplication cyst

No disponible

Biliopancreatic Diversion in the Surgical Treatment of Morbid Obesity: Long-Term Results and Metabolic Consequences.

PURPOSE: In the multidisciplinary therapeutic approach to obesity, bariatric surgery is considered the most effective treatment in weight reduction and the decrease in associated comorbidities. The objective of this work is to describe the long-term clinical and metabolic results in obese patients undergoing biliopancreatic diversion (BPD) according to Scopinaro's technique. MATERIALS AND METHODS: Patients undergoing surgery were followed by the same multidisciplinary team in a study period of 15 years (1999-2015). A retrospective study based on a prospective database was designed, where data on the evolution of obesity-related diseases and nutritional parameters were studied. RESULTS: Two hundred seventy-seven patients were collected; 75.5% were women. The preoperative body mass index (BMI) decreased from 52.5 kg/m2 to 34.9 kg/m2 10 years after surgery. A resolution or improvement of diabetes has been observed in 85.38% of the patients; a decrease in arterial hypertension and obstructive sleep apnea syndrome were in 65.61% and 89.14%, respectively. Throughout the monitoring of the sample, protein malnutrition increased, from 1.8% after the first year of surgery to 4.5% 10 years after the operation. CONCLUSION: Even if Scopinaro's technique is beginning to be replaced by other malabsorptive techniques, it can still be considered as an effective surgical procedure in terms of weight loss, quality of life, and evolution of obesity-related diseases. In order to avoid nutritional deficiencies, the operated patients need a strict follow-up and a supplementation adjusted to the technique.

Aqueous Chemical Solution Deposition of Functional Double Perovskite Epitaxial Thin Films.

Double perovskite structure (A2 BB'O6 ) oxides exhibit a breadth of multifunctional properties with a huge potential range of applications in fields as diverse as spintronics, magneto-optic devices, or catalysis, and most of these applications require the use of thin films and heterostructures. Chemical solution deposition techniques are appearing as a very promising methodology to achieve epitaxial oxide thin films combining high performance with high throughput and low cost. In addition, the physical properties of these materials are strongly dependent on the ordered arrangement of cations in the double perovskite structure. Thus, promoting spontaneous cationic ordering has become a relevant issue. In this work, our recent achievements by using polymer-assisted deposition (PAD) of environmentally friendly, water-based solutions for the growth of epitaxial ferromagnetic insulating double perovskite La2 CoMnO6 and La2 NiMnO6 thin films on SrTiO3 and LaAlO3 single-crystal substrates are presented. It is shown that the particular crystallization and growth process conditions of PAD (very slow rate, close to thermodynamic equilibrium conditions) promote high crystallinity and quality of the films, as well as favors spontaneous B-site cationic ordering.

Spontaneous in-flight assembly of magnetic nanoparticles into macroscopic chains.

Knowing the interactions controlling aggregation processes in magnetic nanoparticles is of strong interest in preventing or promoting nanoparticles' aggregation at wish for different applications. Dipolar magnetic interactions, proportional to the particle volume, are identified as the key driving force behind the formation of macroscopic aggregates for particle sizes above about 20 nm. However, aggregates' shape and size are also strongly influenced by topological ordering. 1-D macroscopic chains of several micrometer lengths are obtained with cube-shaped magnetic nanoparticles prepared by the gas-aggregation technique. Using an analytical model and molecular dynamics simulations, the energy landscape of interacting cube-shaped magnetic nanoparticles is analysed revealing unintuitive dependence of the force acting on particles with the displacement and explaining pathways leading to their assembly into long linear chains. The mechanical behaviour and magnetic structure of the chains are studied by a combination of atomic and magnetic force measurements, and computer simulation. The results demonstrate that [111] magnetic anisotropy of the cube-shaped nanoparticles strongly influences chain assembly features.