CW laser operation around 2-μm in (Tm,Yb):KLu(WO4) 2

Laser generation in continuous wave (CW) regime at 1.94-μm from (Tm,Yb) codoped system has been investigated in two different hosts: KLu(WO 4)2 and KY(WO4)2. The high quality crystals were grown by the Top-Seeded Solution Growth Slow Cooling (TSSG-SC) method with doping levels of 2.5 at. %Tm and 5 at. %Yb. The active media were pumped with a diode laser at 980 nm. We demonstrated the superior performance of KLu(WO4)2 compared to that of KY(WO4) 2 and improved the results already obtained in the literature. The maximum laser output power reached was 157 mW for (Tm,Yb):KLu(WO 4)2 and 123 mW for (Tm,Yb):KY(WO4)2. © 2010 Published by Elsevier Ltd

CW laser operation around 2-μm in (Tm,Yb):KLu(WO4) 2

Laser generation in continuous wave (CW) regime at 1.94-μm from (Tm,Yb) codoped system has been investigated in two different hosts: KLu(WO 4)2 and KY(WO4)2. The high quality crystals were grown by the Top-Seeded Solution Growth Slow Cooling (TSSG-SC) method with doping levels of 2.5 at. %Tm and 5 at. %Yb. The active media were pumped with a diode laser at 980 nm. We demonstrated the superior performance of KLu(WO4)2 compared to that of KY(WO4) 2 and improved the results already obtained in the literature. The maximum laser output power reached was 157 mW for (Tm,Yb):KLu(WO 4)2 and 123 mW for (Tm,Yb):KY(WO4)2. © 2010 Published by Elsevier Ltd

Channel waveguides and Mach-Zehnder structures on RbTiOPO₄ by Cs⁺ ion exchange

Cs+ ion exchange in RbTiOPO4 and (Yb,Nb):RTP/RTP(001) has been used to locally increase the refractive indices for waveguide circuit fabrication. Ti masks were fabricated on RTP samples by conventional photolithography. Cs+ exchange was done using a CsNO3 melt at 698 K during 2 h. Elemental analysis confirms an Cs+ profile with a variable depth. Apparently the Cs+ exchange is disfavored in the doped epitaxial sample. The refractive index variation is higher for nz than for nx,y. Near-field images of the guided modes at 633, 1064 and 1520 nm were recorded. The optical characterization shows propagation losses of 5 dB/cm at 1520 nm

Reactive Ion Etching on (Yb,Nb):RbTiOPO₄/RbTiOPO₄ epitaxial layers for the fabrication of Y-splitters and Mach-Zehnder Interferometers

Rubidium titanyl phosphate RbTiOPO4 (RTP) belongs to a highly diverse and versatile structural family and because of its large non-linear optical coefficients, wide transparency, high laser damage threshold, high chemical stability and low dielectric constants, this material is highly attractive for electro-optic applications such as modulators and Q-switches. RTP has a similar non-linear optical coefficient to KTP but, unlike KTP, it can be doped with Yb3+ ions to obtain a high enough concentration to allow efficient laser action. Because of all these interesting properties, RTP is a strong candidate as a platform material for integrated photonics. Reactive ion etching (RIE) is a commonly used method in etching of semiconductors, but there is little literature available on the plasma-based etching of RTP. Moreover, single-mode rib waveguides have been successfully fabricated in (Yb,Nb):RTP by RIE. In this work, (Yb,Nb):RbTiOPO4/RbTiOPO4 (001) epitaxial layers have been structured by RIE by using a combination of Ar and SF6 gases. The refractive index contrasts between the (Yb,Nb):RbTiOPO4 layer and the RbTiOPO4 substrate at 1.55 microns have been measured

Retos en la incorporación al mercado laboral: análisis de la brecha en competencias [Challenges in entering the labour market: a competence gap analysis]

Este artículo analiza el nivel de adquisición de competencias básicas y transversales a través de la autoevaluación realizada por los alumnos y la valoración realizada por las empresas en las que los alumnos han realizado prácticas durante las etapas finales de sus estudios. Para ello preparamos y distribuimos dos cuestionarios, uno para los estudiantes que desarrollaron las prácticas y otro para los tutores de estudiantes de las empresas. Para analizar los resultados nos hemos centrado en los procedimientos asociados con el análisis de varianza, ANOVA. Más concretamente hemos aplicado el modelo SERVQUAL. Este modelo considera la presencia de diferencias en términos de expectativas y percepciones entre las dos partes implicadas en una prestación de servicios. Identificar las principales brechas en el desarrollo y la evaluación de las competencias de los estudiantes se convierte en un tema clave, ya que es crucial a la hora de determinar no sólo la transición al mercado de trabajo, sino cómo alcanzar las habilidades que los estudiantes deben tener al inicio de su carrera profesional y, por lo tanto, sus posibilidades de éxito o fracaso, las probabilidades de un buen desempeño en la empresa o su capacidad de aprendizaje. [This article studies the acquisition level of basic and transversal skills through a self assessment made by the students and the assessment made by the companies where students have carried out internships during the final stages of their studies. To do this we prepared and distributed two questionnaires, one for the students who completed internships in a firm and another one for the firms’ students’ tutors. To analyse the results we have focused on procedures associated with the analysis of variance, ANOVA. More specifically we have applied the SERVQUAL model. This model considers the presence of differences in terms of expectations and perceptions between the two parties involved in a provision of services. Identifying the main gaps in the development and assessment of the students’ skills becomes a key issue, since it is crucial when determining not only their transition to the labour market, but how to achieve the skills level students must have when they start working and, therefore, their chances of success or failure, the odds of a good performance in the company, or their learning ability.

CD34+cells augment endothelial cell differentiation of CD14+endothelial progenitor cells in vitro

Neovascularization by endothelial progenitor cells (EPC) for the treatment of ischaemic diseases has been a topic of intense research. The CD34+ cell is often designated as EPC, because it contributes to repair of ischaemic injuries through neovascularization. However, incorporation of CD34+ cells into the neovasculature is limited, suggesting another role which could be paracrine. CD14+ cells can also differentiate into endothelial cells and contribute to neovascularization. However, the low proliferative capacity of CD14+ cell-derived endothelial cells hampers their use as therapeutic cells. We made the assumption that an interaction between CD34+ and CD14+ cells augments endothelial differentiation of the CD14+ cells. In vitro, the influence of CD34+ cells on the endothelial differentiation capacity of CD14+ cells was investigated. Endothelial differentiation was analysed by expression of endothelial cell markers CD31, CD144, von Willebrand Factor and endothelial Nitric Oxide Synthase. Furthermore, we assessed proliferative capacity and endothelial cell function of the cells in culture. In monocultures, 63% of the CD14+-derived cells adopted an endothelial cell phenotype, whereas in CD34+/CD14+ co-cultures 95% of the cells showed endothelial cell differentiation. Proliferation increased up to 12% in the CD34+/CD14+ co-cultures compared to both monocultures. CD34-conditioned medium also increased endothelial differentiation of CD14+ cells. This effect was abrogated by hepatocyte growth factor neutralizing antibodies, but not by interleukin-8 and monocyte chemoattractant protein-1 neutralizing antibodies. We show that co-culturing of CD34+ and CD14+ cells results in a proliferating population of functional endothelial cells, which may be suitable for treatment of ischaemic diseases such as myocardial infarction

Tamoxifen and risk of contralateral breast cancer for BRCA1 and BRCA2 mutation carriers

Purpose To determine whether adjuvant tamoxifen treatment for breast cancer (BC) is associated with reduced contralateral breast cancer (CBC) risk for BRCA1 and/or BRCA2 mutation carriers. Methods Analysis of pooled observational cohort data, self-reported at enrollment and at follow-up from the International BRCA1, and BRCA2 Carrier Cohort Study, Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer, and Breast Cancer Family Registry. Eligible women were BRCA1 and BRCA2 mutation carriers diagnosed with unilateral BC since 1970 and no other invasive cancer or tamoxifen use before first BC. Hazard ratios (HRs) for CBC associated with tamoxifen use were estimated using Cox regression, adjusting for year and age of diagnosis, country, and bilateral oophorectomy and censoring at contralateral mastectomy, death, or loss to follow-up. Results Of 1,583 BRCA1 and 881 BRCA2 mutation carriers, 383 (24%) and 454 (52%), respectively, took tamoxifen after first BC d

The comparative responsiveness of Hospital Universitario Princesa Index and other composite indices for assessing rheumatoid arthritis activity

Objective To evaluate the responsiveness in terms of correlation of the Hospital Universitario La Princesa Index (HUPI) comparatively to the traditional composite indices used to assess disease activity in rheumatoid arthritis (RA), and to compare the performance of HUPI-based response criteria with that of the EULAR response criteria. Methods Secondary data analysis from the following studies: ACT-RAY (clinical trial), PROAR (early RA cohort) and EMECAR (pre-biologic era long term RA cohort). Responsiveness was evaluated by: 1) comparing change from baseline (Delta) of HUPI with Delta in other scores by calculating correlation coefficients; 2) calculating standardised effect sizes. The accuracy of response by HUPI and by EULAR criteria was analyzed using linear regressions in which the dependent variable was change in global assessment by physician (Delta GDA-Phy). Results Delta HUPI correlation with change in all other indices ranged from 0.387 to 0.791); HUPI's standardized effect size was larger than those from the other indices in each database used. In ACT-RAY, depending on visit, between 65 and 80% of patients were equally classified by HUPI and EULAR response criteria. However, HUPI criteria were slightly more stringent, with higher percentage of patients classified as non-responder, especially at early visits. HUPI response criteria showed a slightly higher accuracy than EULAR response criteria when using Delta GDA-Phy as gold standard. Conclusion HUPI shows good responsiveness in terms of correlation in each studied scenario (clinical trial, early RA cohort, and established RA cohort). Response criteria by HUPI seem more stringent than EULAR''s

Burden and risk factors for Pseudomonas aeruginosa community-acquired pneumonia:a Multinational Point Prevalence Study of Hospitalised Patients

Pseudornonas aeruginosa is a challenging bacterium to treat due to its intrinsic resistance to the antibiotics used most frequently in patients with community-acquired pneumonia (CAP). Data about the global burden and risk factors associated with P. aeruginosa-CAP are limited. We assessed the multinational burden and specific risk factors associated with P. aeruginosa-CAP. We enrolled 3193 patients in 54 countries with confirmed diagnosis of CAP who underwent microbiological testing at admission. Prevalence was calculated according to the identification of P. aeruginosa. Logistic regression analysis was used to identify risk factors for antibiotic-susceptible and antibiotic-resistant P. aeruginosa-CAP. The prevalence of P. aeruginosa and antibiotic-resistant P. aeruginosa-CAP was 4.2% and 2.0%, respectively. The rate of P. aeruginosa CAP in patients with prior infection/colonisation due to P. aeruginosa and at least one of the three independently associated chronic lung diseases (i.e. tracheostomy, bronchiectasis and/or very severe chronic obstructive pulmonary disease) was 67%. In contrast, the rate of P. aeruginosa-CAP was 2% in patients without prior P. aeruginosa infection/colonisation and none of the selected chronic lung diseases. The multinational prevalence of P. aeruginosa-CAP is low. The risk factors identified in this study may guide healthcare professionals in deciding empirical antibiotic coverage for CAP patients

Autoantibodies against type I IFNs in patients with life-threatening COVID-19

Interindividual clinical variability in the course of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is vast. We report that at least 101 of 987 patients with life-threatening coronavirus disease 2019 (COVID-19) pneumonia had neutralizing immunoglobulin G (IgG) autoantibodies (auto-Abs) against interferon-w (IFN-w) (13 patients), against the 13 types of IFN-a (36), or against both (52) at the onset of critical disease; a few also had auto-Abs against the other three type I IFNs. The auto-Abs neutralize the ability of the corresponding type I IFNs to block SARS-CoV-2 infection in vitro. These auto-Abs were not found in 663 individuals with asymptomatic or mild SARS-CoV-2 infection and were present in only 4 of 1227 healthy individuals. Patients with auto-Abs were aged 25 to 87 years and 95 of the 101 were men. A B cell autoimmune phenocopy of inborn errors of type I IFN immunity accounts for life-threatening COVID-19 pneumonia in at least 2.6% of women and 12.5% of men