To provide a comprehensive overview of geographical patterns (2001-2010) and time trends (1993-2012) of cancer incidence in children aged 0-19 years in Latin America and the Caribbean (LAC) and ...interpret the findings in the context of global patterns.
Geographical variations in 2001-2010 and incidence trends over 1993-2012 in the population of LAC younger than 20 years were described using the database of the third volume of the International Incidence of Childhood Cancer study containing comparable data. Age-specific incidence per million person-years (ASR) was calculated for population subgroups and age-standardized (WSR) using the world standard population.
Overall, 36 744 unique cases were included in this study. In 2001-2010 the overall WSR in age 0-14 years was 132.6. The most frequent were leukemia (WSR 48.7), central nervous system neoplasms (WSR 23.0), and lymphoma (WSR 16.6). The overall ASR in age group 15-19 years was 152.3 with lymphoma ranking first (ASR 30.2). Incidence was higher in males than in females, and higher in South America than in Central America and the Caribbean. Compared with global data LAC incidence was lower overall, except for leukemia and lymphoma at age 0-14 years and the other and unspecified tumors at any age. Overall incidence at age 0-19 years increased by 1.0% per year (95% CI 0.6, 1.3) over 1993-2012. The included registries covered 16% of population aged 0-14 years and 10% of population aged 15-19 years.
The observed patterns provide a baseline to assess the status and evolution of childhood cancer occurrence in the region. Extended and sustained support of cancer registration is required to improve representativeness and timeliness of data for childhood cancer control in LAC.
We report a 5.4sigma detection of pulsed gamma rays from PSR B1821-24 in the globular cluster M28 using ~44 months of Fermi Large Area Telescope (LAT) data that have been reprocessed with improved ...instrument calibration constants. We constructed a phase-coherent ephemeris, with post-fit residual rms of 3 mu s, using radio data spanning ~23.2 yr, enabling measurements of the multi-wavelength light-curve properties of PSR B1821-24 at the milliperiod level. We fold RXTE observations of PSR B1821-24 from 1996 to 2007 and discuss implications on the emission zones. The gamma-ray light curve consists of two peaks separated by 0.41 + or - 0.02 in phase, with the first gamma-ray peak lagging behind the first radio peak by 0.05 + or - 0.02 in phase, consistent with the phase of giant radio pulses. We observe significant emission in the off-peak interval of PSR B1821-24 with a best-fit LAT position inconsistent with the core of M28. We do not detect significant gamma-ray pulsations at the spin or orbital periods from any other known pulsar in M28, and we place limits on the number of energetic pulsars in the cluster. The derived gamma-ray efficiency, ~2%, is typical of other gamma-ray pulsars with comparable spin-down power, suggesting that the measured spin-down rate (2.2 x 10 super(36) erg s super(-1)) is not appreciably distorted by acceleration in the cluster potential. This confirms PSR B1821-24 as the second very energetic millisecond pulsar in a globular cluster and raises the question of whether these represent a separate class of objects that only form in regions of very high stellar density.
Anthropogenic changes to the environment challenge animal populations to adapt to new conditions and unique threats. While the study of adaptation has focused on genetic variation, epigenetic ...mechanisms may also be important. DNA methylation is sensitive to environmental stressors, such as parasites and pesticides, which may affect gene expression and phenotype. We studied the effects of an invasive ectoparasite, Philornis downsi, on DNA methylation of Galápagos mockingbirds (Mimus parvulus). We used the insecticide permethrin to manipulate P. downsi presence in nests of free‐living mockingbirds and tested for effects of parasitism on nestling mockingbirds using epiGBS, a reduced‐representation bisulfite sequencing (RRBS) approach. To distinguish the confounding effects of insecticide exposure, we conducted a matching experiment exposing captive nestling zebra finches (Taeniopygia guttata) to permethrin. We used zebra finches because they were the closest model organism to mockingbirds that we could breed in controlled conditions. We identified a limited number of differentially methylated cytosines (DMCs) in parasitized versus nonparasitized mockingbirds, but the number was not more than expected by chance. In contrast, we saw clear effects of permethrin on methylation in captive zebra finches. DMCs in zebra finches paralleled documented effects of permethrin exposure on vertebrate cellular signaling and endocrine function. Our results from captive birds indicate a role for epigenetic processes in mediating sublethal nontarget effects of pyrethroid exposure in vertebrates. Environmental conditions in the field were more variable than the laboratory, which may have made effects of both parasitism and permethrin harder to detect in mockingbirds. RRBS approaches such as epiGBS may be a cost‐effective way to characterize genome‐wide methylation profiles. However, our results indicate that ecological epigenetic studies in natural populations should consider the number of cytosines interrogated and the depth of sequencing in order to have adequate power to detect small and variable effects.
McNew et al. studied the effects of parasites and permethrin exposure on DNA methylation of nestling birds. They found that permethrin exposure in captivity results in differences in methylation; however, the same differences were not seen in wild birds, in response to either parasitism or permethrin.
We present an analysis of regular timing observations of the high magnetic field Rotating Radio Transient (RRAT) J1819−1458 obtained using the 64-m Parkes and 76-m Lovell radio telescopes over the ...past 5 years. During this time, the RRAT has suffered two significant glitches with fractional frequency changes of 0.6 × 10−6 and 0.1 × 10−6. Glitches of this magnitude are a phenomenon displayed by both radio pulsars and magnetars. However, the behaviour of J1819−1458 following these glitches is quite different to that which follows glitches in other neutron stars, since the glitch activity resulted in a significant long-term net decrease in the slow-down rate. If such glitches occur every 30 years, the spin-down rate, and by inference the magnetic dipole moment, will drop to zero on a time-scale of a few thousand years. There are also significant increases in the rate of pulse detection and in the radio pulse energy immediately following the glitches.
Abstract Arthrocentesis is a technique used for lavage of the inflammatory content of the supradiscal space and lysis of the fibrous strands attaching the articular disc to the superior compartment ...of the temporomandibular joint (TMJ). The most widely accepted and classical manner in which this technique is performed is through two-needle access to the superior joint space. Nevertheless, it has been reported in the literature that this technique is challenging and has several limitations. Thus, the use of a single-puncture approach has been proposed, which represents a less traumatic and easier to perform technique. The single-puncture approach may have several advantages over the classical two-needle approach in regard to completion time, tolerability, stabilization of the needle, and retention of the intra-articular medication. A single-puncture technique is described herein, which uses an intravenous catheter to provide simultaneous inflow/outflow for low or high volume irrigation of the TMJ. The feasibility and low cost of this technique are primary advantages; peripheral intravenous catheters are one of the most widely used devices for vascular access in the primary and hospital healthcare settings.
The Earth's magnetosphere is mainly a collisionless plasma system with non‐Maxwellian particle distributions, which are often fitted by the kappa function. While the Maxwell distribution function is ...described by two parameters (density and temperature), the kappa distribution function has three parameters: density, core energy, and the kappa index that characterizes the slope at high energies. In this study, we fitted an ion flux measured by the five Time History of Events and Macroscale Interactions during Substorms satellites in the Earth's magnetosphere during quiet geomagnetic conditions by a single kappa distribution function. The data were constrained to the following regions: from seven Earth Radii (7 RE) to the Earth's magnetopause at the dayside, and up to 20 RE for other magnetic local time sectors. The two‐dimensional spatial distribution of the fitted parameters and their radial dependencies were analyzed. Regions of high and low κ‐parameter are selected and their formation is discussed.
Key Points
Ion spectra obtained from the Time History of Events and Macroscale Interactions during Substorms satellite mission near the equatorial plane are fitted by a kappa distribution function
Distribution of three fitting parameters (density, core energy, value of k characterizing the spectra slope at high energies) are obtained
Region of increased k index at geocentric distances 8–10 RE is selected
We report the detection of Delta *g-ray pulsations from the high-magnetic-field rotation-powered pulsar PSR J1119--6127 using data from the Fermi Large Area Telescope. The Delta *g-ray light curve of ...PSR J1119--6127 shows a single, wide peak offset from the radio peak by 0.43 ? 0.02 in phase. Spectral analysis suggests a power law of index 1.0 ? 0.3+0.4 -- 0.2 with an energy cutoff at 0.8 ? 0.2+2.0 -- 0.5 GeV. The first uncertainty is statistical and the second is systematic. We discuss the emission models of PSR J1119--6127 and demonstrate that despite the object's high surface magnetic field--near that of magnetars--the field strength and structure in the Delta *g-ray emitting zone are apparently similar to those of typical young pulsars. Additionally, we present upper limits on the Delta *g-ray pulsed emission for the magnetically active PSR J1846--0258 in the supernova remnant Kesteven 75 and two other energetic high-B pulsars, PSRs J1718--3718 and J1734--3333. We explore possible explanations for the non-detection of these three objects, including peculiarities in their emission geometry.
We determined whether maternally influenced early life history traits varied for anchoveta eggs spawned in 2 contrasting environments: off northern (Iquique 23° S) and central (Talcahuano 36° S) ...Chile. Using eggs collected in the field, we showed that free amino acid contents, specific gravity, and vertical distributions of eggs in the water column changed as eggs developed. Specific gravity correlated negatively with free amino acid content. At the inter-population level, differences were determined in free amino acid egg contents (higher in Iquique), specific egg gravity (lower in Iquique), and vertical egg distributions (shallower in Iquique). Specific egg density along with the seawater density distribution and vertical mixing must be taken into account in both areas to explain the observed vertical distributions, as depicted by different egg buoyancy models. Overall, the results of this study suggest that free amino acids might play a role in egg development, potentially modulating specific gravity and egg position in the water column. The observed vertical distribution of eggs at each location and their changes throughout the season seemed to benefit young offspring, allowing them to avoid layers of stressful conditions especially in northern Chile, where a layer of minimum oxygen concentrations occurs near the surface.
•Photoreflectance and ellipsometry spectrums of the GaNAs/GaAs system are studied.•A strategy for evaluate the presence of bandgap splitting is shown.•The influence of other spectral signatures in E+ ...energy range must be evaluated.•Low concentration of n increases the transition overlapping in the spectrums.•By decreasing the sample temperature in measurements, the overlapping is avoided.
Photoreflectance and ellipsometry are two very useful optical spectroscopy techniques employed to analyze the electronic band structure of semiconductors. Photoreflectance and ellipsometry spectra of gallium arsenide nitride (GaNAs) thin films on gallium arsenide (GaAs) layers may be composed of transitions from the conduction bands of the alloy and the binary (E-, E+, and E0, respectively) in conjunction with their interaction spin-orbit split-off valence band (E-+Δ0 and E0+Δ0). For low concentration of nitrogen (between 0.2 and 0.6 %), the determination of the E+ conduction band becomes difficult to distinguish by the fact that critical points are superimposed in the spectrum of both characterization techniques. In this work, a method to determine the E+ conduction band of GaNAs thin films grown on GaAs by molecular beam epitaxy is proposed when the overlapping of spectral features influences their optical determination. When using spectroscopic characterization techniques, the modulation/excitation region depends on the wavelength employed and sample characteristics, and consequently low nitrogen concentration in the alloy in conjunction with the thickness of the GaNAs layers have been found responsible for the signal overlapping. It is demonstrated that by decreasing the sample temperature in the photoreflectance process the overlapping is avoided, allowing for a correct interpretation of the GaNAs conduction band splitting analysis and discarding the contribution of built-in electric fields. From these results, we achieved a precise experimental determination of the presence/absence of the band splitting predicted by the band anti-crossing model using non-destructive characterization tools.
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