High efficiency and circular polarization in SATCOM phased arrays using tri-ridge apertures.

A new antenna array architecture is proposed here to overcome a current bottleneck in phased arrays concerning the enhancement of radiation efficiency and avoidance of scan blindness. In contrast to the conventional approach of using patches with circular or square geometries that exploit 90 or 180 rotational symmetry, this work proposes to use waveguide radiating elements based on 120 symmetry. To implement such symmetry, the tri-ridge aperture is proposed, and its capability to scan widely within a broad frequency bandwidth is demonstrated.

Setting up regional diagnostic reference levels for pediatric interventional cardiology in Latin America and the Caribbean countries: preliminary results and identified challenges.

The goal of the present study was to propose a set of preliminary regional diagnostic reference levels (DRLs) for pediatric interventional cardiology (IC) procedures in Latin America and the Caribbean countries, classified by age and weight groups. The study was conducted in the framework of the Optimization of Protection in Pediatric Interventional Radiology in Latin America and the Caribbean program coordinated by the World Health Organization and the Pan American Health Organization in cooperation with the International Atomic Energy Agency. The first step of the program was focused on pediatric IC.

Modulated scattering technique in the terahertz domain enabled by current actuated vanadium dioxide switches.

The modulated scattering technique is based on the use of reconfigurable electromagnetic scatterers, structures able to scatter and modulate an impinging electromagnetic field in function of a control signal. The modulated scattering technique is used in a wide range of frequencies up to millimeter waves for various applications, such as field mapping of circuits or antennas, radio-frequency identification devices and imaging applications. However, its implementation in the terahertz domain remains challenging.

Self-biased reconfigurable graphene stacks for terahertz plasmonics.

The gate-controllable complex conductivity of graphene offers unprecedented opportunities for reconfigurable plasmonics at terahertz and mid-infrared frequencies. However, the requirement of a gating electrode close to graphene and the single 'control knob' that this approach offers limits the practical implementation and performance of these devices. Here we report on graphene stacks composed of two or more graphene monolayers separated by electrically thin dielectrics and present a simple and rigorous theoretical framework for their characterization.

Vaporization of the prostate with 150-w thulium laser: complications with 6-month follow-up.

Unlabelled: Purpose: To analyze the efficacy and safety of vaporization of the prostate (VP) with the 150-W thulium:yttrium-aluminum-garnet (Tm:YAG) laser.

Patients And Methods: In a prospective series of 55 patients with small- and medium-size prostates undergoing major outpatient surgery (MOS), the primary objectives were to analyze changes in maximum flow (Qmax) and International Prostate Symptom Score (IPSS) after 6 months. Immediate (<30 days) and late (>30 days) complications were subsequently recorded.

ZRF1 controls the retinoic acid pathway and regulates leukemogenic potential in acute myeloid leukemia.

Acute myeloid leukemia (AML) is frequently linked to epigenetic abnormalities and deregulation of gene transcription, which lead to aberrant cell proliferation and accumulation of undifferentiated precursors. ZRF1, a recently characterized epigenetic factor involved in transcriptional regulation, is highly overexpressed in human AML, but it is not known whether it plays a role in leukemia progression. Here, we demonstrate that ZRF1 depletion decreases cell proliferation, induces apoptosis and enhances cell differentiation in human AML cells.

Transcriptional organization of the region encoding the synthesis of the flagellar filament in Pseudomonas fluorescens.

Pseudomonas fluorescens F113 is motile by means of type b flagella. Analysis of the region encoding the synthesis of the flagellar filament has shown a transcriptional organization different from that of type a flagella. Additionally to the promoters driving fliC, fliD, and fleQ expression, we have found promoters upstream of the flaG gene and the fliST operon.

Acclimatization of rats after ground transportation to a new animal facility.

This study aimed to assess the time needed by rats, which had not been previously transported, to acclimate to a new environment after 5 h of van transport, using physiological parameters as measures of acclimatization. Animal shipping boxes and transport van conditions were standardized to minimize stress factors that could be associated with transport. Heart rate (HR), body temperature and activity levels were measured in the rats before and after transport using previously implanted radio-telemetry transmitters.

Antioxidant patterns (superoxide dismutase, glutathione reductase, and glutathione peroxidase) in kidneys from non-heart-beating-donors: experimental study.

Introduction: The evolution of renal antioxidant concentrations in the different phases of a non-heart-beating donor (NHBD) transplant after prolonged warm ischemia (40 and 90 minutes) and the effect of normothermic extracorporeal recirculation (37 degrees C) for 30 minutes were evaluated on antioxidant tissue concentrations in the kidney.

Methods: Forty pairs of pigs, were divided into groups of 10 as follows: group 0, control donor with beating heart; group 1, 40 minutes of warm ischemia without recirculation by cardiopulmonary bypass pump (groups 2 and 3); group 2, 40 minutes of warm ischemia and recirculation for 30 minutes at 37 degrees C; and group 3, 90 minutes of warm ischemia and recirculation for 30 minutes at 37 degrees C. The concentrations of superoxide dismutase (SOD), glutathione peroxidase, and glutathione reductase were determined at the tissue level by biopsy at baseline the end of warm ischemia, the end of recirculation, at the end of cold ischemia, and 1 hour after reperfusion.

Two site-specific recombinases are implicated in phenotypic variation and competitive rhizosphere colonization in Pseudomonas fluorescens.

The biocontrol agent Pseudomonas fluorescens F113 undergoes phenotypic variation during rhizosphere colonization, and this variation has been related to the activity of a site-specific recombinase encoded by the sss gene. Here, it is shown that a second recombinase encoded by the xerD gene is also implicated in phenotypic variation. A putative xerD gene from this strain was cloned, and sequence analysis confirmed that it encoded a site-specific recombinase of the lambda integrase family.

Analysis of Pseudomonas fluorescens F113 genes implicated in flagellar filament synthesis and their role in competitive root colonization.

The ability of plant-associated micro-organisms to colonize and compete in the rhizosphere is specially relevant for the biotechnological application of micro-organisms as inoculants. Pseudomonads are one of the best root colonizers and they are widely used in plant-pathogen biocontrol and in soil bioremediation. This study analyses the motility mechanism of the well-known biocontrol strain Pseudomonas fluorescens F113.