Electronically Tuned Local Oscillators for the NOEMA Interferometer

We present an overview of the electronically tuned local oscillator (LO) system developed at the Institut de RadioAstronomie millimetrique (IRAM) for the superconductor-insulator-superconductor (SIS) receivers of the NOrthern Extended Millimeter Array interferometer (NOEMA). We modified the frequency bands and extended the bandwidths of the LO designs developed by the National Radio Astronomy Observatory (NRAO) for the Atacama Large Millimeter Array (ALMA) project to cover the four NOEMA LO frequency ranges 82-108.3 GHz (Band 1), 138.6-171.3 GHz (Band 2), 207.7-264.4 GHz (Band 3), and 283-365 GHz (Band 4). The NOEMA LO system employs commercially available MMICs and GaAs millimeter MMICs from NRAO which are micro-assembled into active multiplied chain (AMC) and power amplifier (PA) modules. We discuss the problem of the LO spurious harmonics and of the LO signal directly multiplied by the SIS mixers that add extra noise and lead to detections of unwanted spectral lines from higher order sidebands. A waveguide filter in the LO path is used to reduce the higher order harmonics level of the LO at the output of the final frequency multiplier, thus mitigating the undesired effects and improving the system noise temperature

Estrategias cognitivas y de autorregulación, engagement académico y rendimiento académico en estudiantes del nivel superior. El rol mediador de la comprensión lectora

The aim of the present study was to examine the relationship between students’ cognitive and self-regulatory strategies, academic engagement, and academic achievement in higher education, analyzing the mediating role of reading comprehension. Different tasks to assess the constructs were administered to 209 students (Mage = 21.71; SD = 4.36). The students' GPA was used as a measure of academic achievement. Significant associations were found between cognitive and self-regulation strategies, academic engagement, reading comprehension, and students' GPA. In addition, a positive association was found between cognitive and self-regulation strategies and academic engagement. Finally, the structural equation model showed that cognitive and self-regulation strategies and academic engagement have direct effects on students' GPA. Additionally, an indirect effect of cognitive and self-regulation strategies on academic achievement was observed through reading comprehension. The implications of the study are discussed in terms of the importance of promoting the recognition and implementation of students' own cognitive and metacognitive strategies and engagement, in order to improve their academic achievement in higher education.El objetivo del presente estudio fue examinar la relación entre las estrategias cognitivas y de autorregulación, el engagement académico y el rendimiento académico (RA) en estudiantes del nivel superior, analizando el rol mediador de la comprensión lectora. Se administraron diferentes tareas para evaluar los constructos a 209 estudiantes (Medad = 21.71; DE = 4.36). Para valorar el rendimiento académico se empleó el promedio académico de los estudiantes. Se hallaron asociaciones significativas entre las estrategias cognitivas y de autorregulación, el engagement académico, la comprensión lectora y el rendimiento académico de los estudiantes. Además, se observó una correlación entre las estrategias cognitivas y de autorregulación y el engagement académico del estudiante. Finalmente, el análisis de ecuaciones estructurales (SEM) mostró que las estrategias cognitivas y de autorregulación y el engagement académico tienen efectos directos en el RA. Además, se observó un efecto indirecto de las estrategias cognitivas y de autorregulación en el RA a través de la comprensión lectora. Se discuten las implicaciones del estudio en función de la relevancia de promover el reconocimiento e implementación de las propias estrategias cognitivas y metacognitivas y el engagement del estudiante, para favorecer su desempeño académico en el nivel superior

Walking Outcome After Traumatic Paraplegic Spinal Cord Injury: The Function of Which Myotomes Makes a Difference?

BACKGROUND: Accurate prediction of walking function after a traumatic spinal cord injury (SCI) is crucial for an appropriate tailoring and application of therapeutical interventions. Long-term outcome of ambulation is strongly related to residual muscle function acutely after injury and its recovery potential. The identification of the underlying determinants of ambulation, however, remains a challenging task in SCI, a neurological disorder presented with heterogeneous clinical manifestations and recovery trajectories. OBJECTIVES: Stratification of walking function and determination of its most relevant underlying muscle functions based on stratified homogeneous patient subgroups. METHODS: Data from individuals with paraplegic SCI were used to develop a prediction-based stratification model, applying unbiased recursive partitioning conditional inference tree (URP-CTREE). The primary outcome was the 6-minute walk test at 6 months after injury. Standardized neurological assessments ≤15 days after injury were chosen as predictors. Resulting subgroups were incorporated into a subsequent node-specific analysis to attribute the role of individual lower extremity myotomes for the prognosis of walking function. RESULTS: Using URP-CTREE, the study group of 361 SCI patients was divided into 8 homogeneous subgroups. The node specific analysis uncovered that proximal myotomes L2 and L3 were driving factors for the differentiation between walkers and non-walkers. Distal myotomes L4-S1 were revealed to be responsible for the prognostic distinction of indoor and outdoor walkers (with and without aids). CONCLUSION: Stratification of a heterogeneous population with paraplegic SCI into more homogeneous subgroups, combined with the identification of underlying muscle functions prospectively determining the walking outcome, enable potential benefit for application in clinical trials and practice

Pericytes support neutrophil subendothelial cell crawling and breaching of venular walls in vivo

Wellcome Trust (081172/Z/06/Z) to S. Nourshargh. D. Proebstl was supported by a Medical Research Council PhD studentship awarded to Barts and The London Medical School, and J. Whiteford is an Arthritis Research UK Fellow

The Front-End of the NOEMA Interferometer

The IRAM Plateau de Bure Interferometer (PdBI) is being upgraded to a new powerful millimeter-wave radio astronomy facility called the NOrthern Extended Millimeter Array (NOEMA) which will double the number of the 15-m diameter antennas from six to 12. All antennas will be equipped with a new generation of dual-polarization Front-End covering the 72-373-GHz frequency range with four independent receivers integrated into a single cryostat. All receivers utilize sideband separating (2SB) superconductor-insulator-superconductor (SIS) mixers, each of which delivers two ~7.7-GHz-wide intermediate frequency (IF) outputs per polarization channel, thus increasing the total IF bandwidth which can be processed with a single setting of the interferometer from 8 GHz (2 × 4 GHz delivered by the existing PdBI Front-End) to ~31 GHz (4 × 7.7 GHz delivered by the NOEMA Front-End). The first of the new NOEMA antennas (Ant. 7) has recently been completed and the first NOEMA Front-End successfully developed and installed in it. For the coming years, our goal is to upgrade all of the Front-Ends currently installed on the six existing PdBI antennas to the new NOEMA standard and to build six additional ones (plus one spare) for the new NOEMA antennas. In this paper, we describe the design, fabrication, and assembly of the Front-End we have developed for NOEMA Antenna 7. The instrument has state-of-the-art performance and sets a new standard in the post-ALMA generation technology

Elevated Autoantibodies in Subacute Human Spinal Cord Injury Are Naturally Occurring Antibodies

Spinal cord injury (SCI) results in long-term neurological and systemic consequences, including antibody-mediated autoimmunity, which has been related to impaired functional recovery. Here we show that autoantibodies that increase at the subacute phase of human SCI, 1 month after lesion, are already present in healthy subjects and directed against non-native proteins rarely present in the normal spinal cord. The increase of these autoantibodies is a fast phenomenon–their levels are already elevated before 5 days after lesion–characteristic of secondary immune responses, further supporting their origin as natural antibodies. By proteomics studies we have identified that the increased autoantibodies are directed against 16 different nervous system and systemic self-antigens related to changes known to occur after SCI, including alterations in neural cell cytoskeleton, metabolism and bone remodeling. Overall, in the context of previous studies, our results offer an explanation to why autoimmunity develops after SCI and identify novel targets involved in SCI pathology that warrant further investigation