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We report the first detection of gravitational lensing due to galaxy clusters using only the polarization of the cosmic microwave background (CMB). The lensing signal is obtained using a new estimator that extracts the lensing dipole signature from stacked images formed by rotating the cluster-centered Stokes QU map cutouts along the direction of the locally measured background CMB polarization gradient. Using data from the SPTpol 500 deg^{2} survey at the locations of roughly 18 000 clusters with richness λ≥10 from the Dark Energy Survey (DES) Year-3 full galaxy cluster catalog, we detect lensing at 4.8σ. The mean stacked mass of the selected sample is found to be (1.43±0.40)×10^{14}M_{â} which is in good agreement with optical weak lensing based estimates using DES data and CMB-lensing based estimates using SPTpol temperature data. This measurement is a key first step for cluster cosmology with future low-noise CMB surveys, like CMB-S4, for which CMB polarization will be the primary channel for cluster lensing measurements.
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Gravitational lensing of the cosmic microwave background generates a curl pattern in the observed polarization. This "B-mode" signal provides a measure of the projected mass distribution over the entire observable Universe and also acts as a contaminant for the measurement of primordial gravity-wave signals. In this Letter we present the first detection of gravitational lensing B modes, using first-season data from the polarization-sensitive receiver on the South Pole Telescope (SPTpol). We construct a template for the lensing B-mode signal by combining E-mode polarization measured by SPTpol with estimates of the lensing potential from a Herschel-SPIRE map of the cosmic infrared background. We compare this template to the B modes measured directly by SPTpol, finding a nonzero correlation at 7.7σ significance. The correlation has an amplitude and scale dependence consistent with theoretical expectations, is robust with respect to analysis choices, and constitutes the first measurement of a powerful cosmological observable.
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The increasing scale of cryogenic detector arrays for submillimeter and millimeter wavelength astrophysics has led to the need for large aperture, high index of refraction, low loss, cryogenic refracting optics. Silicon with n=3.4, low loss, and high thermal conductivity is a nearly optimal material for these purposes but requires an antireflection (AR) coating with broad bandwidth, low loss, low reflectance, and a matched coefficient of thermal expansion. We present an AR coating for curved silicon optics comprised of subwavelength features cut into the lens surface with a custom three-axis silicon dicing saw. These features constitute a metamaterial that behaves as a simple dielectric coating. We have fabricated silicon lenses as large as 33.4 cm in diameter with micromachined layers optimized for use between 125 and 165 GHz. Our design reduces average reflections to a few tenths of a percent for angles of incidence up to 30° with low cross polarization. We describe the design, tolerance, manufacture, and measurements of these coatings and present measurements of the optical properties of silicon at millimeter wavelengths at cryogenic and room temperatures. This coating and lens fabrication approach is applicable from centimeter to submillimeter wavelengths and can be used to fabricate coatings with greater than octave bandwidth.
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OBJECTIVES: Understanding how aging impacts swallowing can help differentiate typical from atypical behaviors. This study aimed to quantify age-related swallowing alterations observed during a modified barium swallow study. DESIGN: Cross-sectional study. SETTING: Adult fluoroscopy suite in a metropolitan hospital at an academic center. PARTICIPANTS: 195 healthy adults distributed across 3 age categories: 21-39; 40-59; 60+ years. MEASUREMENTS: 17 physiologic components of swallowing across three functional domains (oral, pharyngeal, esophageal), including summed composite scores (Oral Total [OT] and Pharyngeal Total [PT]), from the validated and standardized Modified Barium Swallow Impairment Profile. RESULTS: Most components (65%) demonstrated no impairment (scores of "0"). The odds of a worse (higher) score increased significantly with age for: Tongue Control during Bolus Hold, Hyolaryngeal Movement, Laryngeal Closure, Pharyngeal Contraction, and Pharyngoesophageal Segment Opening. OT and PT scores for 40-59-year-olds were worse than the youngest group (p=.01 and p <.001, respectively). Adults 60+ years had significantly worse PT scores among all groups (p-values <.01). CONCLUSION: Oropharyngeal swallowing physiology evolves as healthy adults age and should be considered during clinical decision-making.
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Trastornos de Deglución , Deglución , Humanos , Deglución/fisiología , Bario , Estudios Transversales , FluoroscopíaRESUMEN
We describe the design and measurement of feedhorn-coupled, transition-edge sensor (TES) polarimeters with two passbands centered at 220 GHz and 280 GHz, intended for observations of the cosmic microwave background. Each pixel couples polarized light in two linear polarizations by use of a planar orthomode transducer and senses power via four TES bolometers, one for each band in each linear polarization. Previous designs of this detector architecture incorporated passbands from 27 to 220 GHz; we now demonstrate this technology at frequencies up to 315 GHz. Observational passbands are defined with an on-chip diplexer, and Fourier-transform-spectrometer measurements are in excellent agreement with simulations. We find coupling from feedhorn to TES bolometer using a cryogenic, temperature-controlled thermal source. We determine the optical efficiency of our device is η = 77% ± 6% (75% ± 5%) for 220 (280) GHz, relative to the designed passband shapes. Lastly, we compare two power-termination schemes commonly used in wide-bandwidth millimeter-wave polarimeters and find equal performance in terms of optical efficiency and passband shape.
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Griseofulvin, a fungistatic agent, was administered in oral doses of 125 to 1500 milligrams per kilogramn per day to pregnant rats during organogenesis. Evaluation of the offspring from dams treated with the largest doses, 63 and 75 times a therapeutic dose in man, indicated decreased survival rates and a syndrome of malformations.
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Anomalías Inducidas por Medicamentos , Griseofulvina/efectos adversos , Anomalías Múltiples/inducido químicamente , Administración Oral , Animales , Peso al Nacer/efectos de los fármacos , Huesos/anomalías , Femenino , Fertilidad/efectos de los fármacos , Muerte Fetal/inducido químicamente , Griseofulvina/administración & dosificación , Masculino , Embarazo , Ratas , Espermatogénesis/efectos de los fármacosRESUMEN
Microwave Kinetic Inductance Detectors (MKIDs) provide a compelling path forward to the large-format polarimeter, imaging, and spectrometer arrays needed for next-generation experiments in millimeter-wave cosmology and astronomy. We describe the development of feedhorn-coupled MKID detectors for the TolTEC millimeter-wave imaging polarimeter being constructed for the 50-meter Large Millimeter Telescope (LMT). Observations with TolTEC are planned to begin in early 2019. TolTEC will comprise â¼7,000 polarization sensitive MKIDs and will represent the first MKID arrays fabricated and deployed on monolithic 150 mm diameter silicon wafers - a critical step towards future large-scale experiments with over 105 detectors. TolTEC will operate in observational bands at 1.1, 1.4, and 2.0 mm and will use dichroic filters to define a physically independent focal plane for each passband, thus allowing the polarimeters to use simple, direct-absorption inductive structures that are impedance matched to incident radiation. This work is part of a larger program at NIST-Boulder to develop MKID-based detector technologies for use over a wide range of photon energies spanning millimeter-waves to X-rays. We present the detailed pixel layout and describe the methods, tools, and flexible design parameters that allow this solution to be optimized for use anywhere in the millimeter and sub-millimeter bands. We also present measurements of prototype devices operating in the 1.1 mm band and compare the observed optical performance to that predicted from models and simulations.
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Fundamental to the process of mammalian development is the timed and coordinated regulation of gene expression. This requires transcription of a precise subset of the total complement of genes. It is clear that chromatin architecture plays a fundamental role in this process by either facilitating or restricting transcription factor binding [1]. How such specialized chromatin structures are established to regulate gene expression is poorly understood. All eukaryotic organisms contain specialized histone variants with distinctly different amino acid sequences that are even more conserved than the major core histones [2]. On the basis of their highly conserved sequence, histone variants have been assumed critical for the function of mammalian chromatin; however, a requirement for a histone variant has not been shown in mammalian cells. Mice with a deletion of H1 degrees have been generated by gene targeting in ES cells, but these mice show no phenotypic consequences, perhaps due to redundancy of function [3]. Here we show for the first time that a mammalian histone variant, H2A.Z, plays a critical role in early development, and we conclude that this histone variant plays a pivotal role in establishing the chromatin structures required for the complex patterns of gene expression essential for normal mammalian development.
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Desarrollo Embrionario y Fetal/fisiología , Histonas/fisiología , Animales , Secuencia de Bases , Línea Celular , Cartilla de ADN , Eliminación de Gen , Histonas/genética , RatonesRESUMEN
'Continuous effort, not strength or intelligence, is the key to understanding our potential.' Margaret J Wheatley. The focus of any academic or research author is to share his or her findings, and to gain respect and reward for publishing. The ideal journal is one that not only publishes an article quickly but also helps the author to improve the article before publication through peer review, selects only the best research so that the author's article lies alongside other high quality articles, and provides maximum (and long-term) visibility and access to the article. Unfortunately, in the real world, authors need to make tradeoffs between high quality journals, those that work quickly, those that are willing to accept the article and those that provide the best access. Into this mix has come the potential of open access as a means of increasing visibility: journals publish the article without a subscription barrier so anyone, anywhere, can read the article. However, the growth of open access (pushed by institutions, grant bodies and governments as a means of improving human health and knowledge) has come with some unforeseen consequences. In this article, Jeffrey Beall discusses one recent phenomenon that has arisen from the open access movement: that of 'predatory publishers'. These are individuals or companies that use the open access financial system (author pays, rather than library subscribes) to defraud authors and readers by promising reputable publishing platforms but delivering nothing of the sort. They frequently have imaginary editorial boards, do not operate any peer review or quality control, are unclear about payment requirements and opaque about ownership or location, include plagiarised content and publish whatever somebody will pay them to publish. Predatory publishers generally make false promises to authors and behave unethically. They also undermine the scholarly information and publishing environment with a deluge of poor quality, unchecked and invalidated articles often published on temporary sites, thus losing the scholarly record. Jeffrey Beall, a librarian in Denver, US, has watched the rise of such fraudulent practice, and manages a blog site that names publishers and journals that he has identified as predatory. While Beall's lists can provide librarians and knowledgeable authors with information on which journals and publishers to be cautious about, several legitimate publishers, library groups and others have joined forces to educate and inform authors in what to look for when selecting journals to publish in (or read). This initiative, called Think. Check. Submit. (http://thinkchecksubmit.org/), was launched in the latter half of 2015 and hopes to raise awareness of disreputable journals while clearly separating them from valid, high quality, open access journals (of which there are many). PIPPA SMART Guest Editor.
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Cirugía General , Publicaciones Periódicas como Asunto/normas , Edición/normas , HumanosRESUMEN
Portions of nitrocellulose filters containing blotted electrophoresed antigens of Schistosoma japonicum adult worms were reacted with polyclonal rabbit antisera raised to this human parasite. Eluted antibodies were used as probes for detection of antigen-positive clones in an Escherichia coli lambda gt11 amp3 expression library of adult worm cDNA. Several cloned antigens corresponding to a S. japonicum antigen of Mr 26 000, being sought as a candidate vaccine molecule in a mouse model of schistosomiasis japonica, were identified using this approach. The method provides an antibody reagent that is an attractive alternative to other more tedious means of producing oligospecific antibodies, including monoclonal antibodies, for screening of expression libraries.
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Antígenos Helmínticos/genética , Schistosoma japonicum/inmunología , Animales , Anticuerpos/inmunología , Antígenos Helmínticos/inmunología , Precipitación Química , Clonación Molecular , ADN/genética , Técnicas de Inmunoadsorción , Schistosoma japonicum/genéticaRESUMEN
A cloned library of DNA complementary to the mRNA of adult Schistosoma japonicum has been prepared and expressed as fusion proteins with Escherichia coli beta-galactosidase. Colonies expressing the S. japonicum cDNA clones were screened both with antibodies from individuals with a history of schistosomiasis and with antibodies obtained from a rabbit immunized with whole adult worms. In both cases colonies were detected which bound antibody, although the frequency of antigen-positive clones was much higher with the rabbit antiserum than with human sera. In both cases the proportion of colonies reacting with antibodies was markedly lower than that published for equivalent screens of Plasmodium falciparum cDNA with sera from individuals with a history of falciparum malaria. Several major S. japonicum antigens were identified by the affinity purification of antibodies using immobilised fusion proteins produced during lytic growth of the recombinant bacteriophage.
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Antígenos Helmínticos/genética , Proteínas Recombinantes/genética , Schistosoma japonicum/inmunología , Anticuerpos/aislamiento & purificación , Cromatografía de Afinidad , Clonación Molecular , ADN/genética , Escherichia coli/genética , Regulación de la Expresión Génica , Vectores Genéticos , Schistosoma japonicum/genéticaRESUMEN
The U.S. Department of Energy (U.S. DOE) maintains several programs to study and understand the health and environmental effects of exposure to low levels of energy-related agents. These programs include research to understand the mechanisms of action of agents of concern and to assess the risks associated with exposures of people and ecological systems to these agents. They also include implementing appropriate occupational safety and health standards and remediating waste sites to environmental standards. These programs require that the U.S. DOE pursue a realistic understanding of the effects of exposures to small amounts of energy-related agents. The largest of these programs involves hazardous waste remediation and includes potentially harmful exposures to low levels of numerous agents. The U.S. DOE conducts research to establish the scientific bases for the realistic assessment of risks of exposure to such wastes. As part of the U.S. DOE efforts to understand the risks of low-level exposures to hazardous waste, the Office of Health and Environmental Research and the Office of Environmental Management recently launched a broad cooperative program. It is comprised of research projects in nine general scientific areas and includes research on the health impacts and risk estimation of exposure to low levels of hazardous wastes. Projects for this new cooperative research program were selected from 610 applications and totaled approximately $47 million in fiscal year 1996. This program marks a new approach by using basic research to reduce cleanup costs and to develop scientific foundations for advances in environmental technologies. The research will also examine the effects of exposure to low levels of chemical and radiological wastes.
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Residuos Peligrosos/efectos adversos , HumanosRESUMEN
Human sera taken from patients with chronic schistosomiasis japonica have been demonstrated to have two effects on mice. Sera from those patients reduced the size of granuloma in mice sensitised for accelerated granuloma formation to eggs entrapped in the lungs of mice injected with the sera shortly before and at day 2 after intravenous egg challenge. The sera with this effect on the mouse lung granuloma models caused large segmented precipitates in the optimised circumoval precipitin test (COPT). Such sera also reduced the rate at which eggs matured in the liver and intestines of mice infected with S. japonicum. The results strongly support our postulate that a major cause of granuloma modulation in cases of chronic schistosomiasis japonica is antiembryonation immunity and that mice provide useful models for the analysis of our postulate. Identification of egg antigens responsible for the anti-embryonation effect should facilitate progress towards the development of a vaccine against granulomatous disease.
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Esquistosomiasis Japónica/inmunología , Animales , Antígenos de Protozoos/inmunología , Granuloma/inmunología , Granuloma/parasitología , Humanos , Enfermedades Pulmonares/inmunología , Enfermedades Pulmonares/parasitología , Ratones , Ratones Endogámicos BALB C , Óvulo/citología , Óvulo/inmunología , Recuento de Huevos de Parásitos , Schistosoma japonicum/citología , Schistosoma japonicum/inmunología , Esquistosomiasis Japónica/sangre , Esquistosomiasis Japónica/parasitologíaRESUMEN
Improvements in superconductor device fabrication, detector hybridization techniques, and superconducting quantum interference device readout have made square-centimeter-sized arrays of gamma-ray microcalorimeters, based on transition-edge sensors (TESs), possible. At these collecting areas, gamma microcalorimeters can utilize their unprecedented energy resolution to perform spectroscopy in a number of applications that are limited by closely-spaced spectral peaks, for example, the nondestructive analysis of nuclear materials. We have built a 256 pixel spectrometer with an average full-width-at-half-maximum energy resolution of 53 eV at 97 keV, a useable dynamic range above 400 keV, and a collecting area of 5 cm(2). We have demonstrated multiplexed readout of the full 256 pixel array with 236 of the pixels (91%) giving spectroscopic data. This is the largest multiplexed array of TES microcalorimeters to date. This paper will review the spectrometer, highlighting the instrument design, detector fabrication, readout, operation of the instrument, and data processing. Further, we describe the characterization and performance of the newest 256 pixel array.