293 research outputs found
A comparison of the response of PADC neutron dosemeters in high-energy neutron fields
Within the framework of the EURADOS Working Group 11, a comparison of passive neutron dosemeters in high-energy neutron fields was organised in 2011. The aim of the exercise was to evaluate the response of poly-allyl-glycol-carbonate neutron dosemeters from various European dosimetry laboratories to high-energy neutron fields. Irradiations were performed at the iThemba LABS facility in South Africa with neutrons having energies up to 66 and 100 Me
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The Prevalence and Clinical Implications of Comorbid Back Pain in Shoulder Instability: A Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability Cohort Study.
Background:Understanding predictors of pain is critical, as recent literature shows that comorbid back pain is an independent risk factor for worse functional and patient-reported outcomes (PROs) as well as increased opioid dependence after total joint arthroplasty. Purpose/Hypothesis:The purpose of this study was to evaluate whether comorbid back pain would be predictive of pain or self-reported instability symptoms at the time of stabilization surgery. We hypothesized that comorbid back pain will correlate with increased pain at the time of surgery as well as with worse scores on shoulder-related PRO measures. Study Design:Cross-sectional study; Level of evidence, 3. Methods:As part of the Multicenter Orthopaedic Outcomes Network (MOON) Shoulder Instability cohort, patients consented to participate in pre- and intraoperative data collection. Demographic characteristics, injury history, preoperative PRO scores, and radiologic and intraoperative findings were recorded for patients undergoing surgical shoulder stabilization. Patients were also asked, whether they had any back pain. Results:The study cohort consisted of 1001 patients (81% male; mean age, 24.1 years). Patients with comorbid back pain (158 patients; 15.8%) were significantly older (28.1 vs 23.4 years; P < .001) and were more likely to be female (25.3% vs 17.4%; P = .02) but did not differ in terms of either preoperative imaging or intraoperative findings. Patients with self-reported back pain had significantly worse preoperative pain and shoulder-related PRO scores (American Shoulder and Elbow Surgeons score, Western Ontario Shoulder Instability Index) (P < .001), more frequent depression (22.2% vs 8.3%; P < .001), poorer mental health status (worse scores for the RAND 36-Item Health Survey Mental Component Score, Iowa Quick Screen, and Personality Assessment Screener) (P < .01), and worse preoperative expectations (P < .01). Conclusion:Despite having similar physical findings, patients with comorbid back pain had more severe preoperative pain and self-reported symptoms of instability as well as more frequent depression and lower mental health scores. The combination of disproportionate shoulder pain, comorbid back pain and mental health conditions, and inferior preoperative expectations may affect not only the patient's preoperative state but also postoperative pain control and/or postoperative outcomes
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The GAPS Programme at TNG XXXVII. A precise density measurement of the young ultra-short period planet TOI-1807 b
Context. Great strides have been made in recent years in the understanding of the mechanisms involved in the formation and evolution of planetary systems. Despite this, many observational findings have not yet been corroborated by astrophysical explanations. A fine contribution to the study of planetary formation processes comes from the study of young, low-mass planets, with short orbital periods (.100 days). In the last three years, the NASA/TESS satellite has identified many planets of this kind and their characterization is clearly necessary in order to understand how they formed and evolved. Aims. Within the framework of the Global Architecture of Planetary System (GAPS) project, we performed a validation and characterization (radius and mass) of the ultra-short period planet TOI-1807 b, which orbits its young host star BD+39 2643 (âŒ300 Myr) in only 13 h. This is the youngest ultra-short period planet discovered so far. Methods. Thanks to a joint modeling of the stellar activity and planetary signals in the TESS light curve and in new HARPS-N radial-velocity measurements, combined with accurate estimation of stellar parameters, we validated the planetary nature of TOI-1807 b and measured its orbital and physical parameters. Results. By using astrometric, photometric, and spectroscopic observations, we found that BD+39 2643 is a young, active K dwarf star and a member of a 300 ± 80 Myr old moving group. Furthermore, it rotates in Prot = 8.8 ± 0.1 days. This star hosts an ultra-short period planet, exhibiting an orbital period of only Pb = 0.54937 ± 0.00001 days. Thanks to the exquisite photometric and spectroscopic series, along with the accurate information on its stellar activity, we measured both the radius and the mass of TOI-1807 b with high precision, obtaining RP,b = 1.37 ± 0.09 Râ and MP,b = 2.57 ± 0.50 Mâ. These planet parameters correspond to a rocky planet with an Earth-like density (Ïb = 1.0 ± 0.3 Ïâ) and no extended H/He envelope. From the analysis of the age-RP distribution for planets with well measured ages, we inferred that TOI-1807 b may have already lost a large part of its atmosphere over the course of its 300 Myr lifetime
First radial velocity results from the MINiature Exoplanet Radial Velocity Array (MINERVA)
The MINiature Exoplanet Radial Velocity Array (MINERVA) is a dedicated
observatory of four 0.7m robotic telescopes fiber-fed to a KiwiSpec
spectrograph. The MINERVA mission is to discover super-Earths in the habitable
zones of nearby stars. This can be accomplished with MINERVA's unique
combination of high precision and high cadence over long time periods. In this
work, we detail changes to the MINERVA facility that have occurred since our
previous paper. We then describe MINERVA's robotic control software, the
process by which we perform 1D spectral extraction, and our forward modeling
Doppler pipeline. In the process of improving our forward modeling procedure,
we found that our spectrograph's intrinsic instrumental profile is stable for
at least nine months. Because of that, we characterized our instrumental
profile with a time-independent, cubic spline function based on the profile in
the cross dispersion direction, with which we achieved a radial velocity
precision similar to using a conventional "sum-of-Gaussians" instrumental
profile: 1.8 m s over 1.5 months on the RV standard star HD 122064.
Therefore, we conclude that the instrumental profile need not be perfectly
accurate as long as it is stable. In addition, we observed 51 Peg and our
results are consistent with the literature, confirming our spectrograph and
Doppler pipeline are producing accurate and precise radial velocities.Comment: 22 pages, 9 figures, submitted to PASP, Peer-Reviewed and Accepte
TOI-431/HIP 26013: A super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet
We present the bright (Vmag = 9.12), multiplanet system TOI-431, characterized with photometry and radial velocities (RVs). We estimate the stellar rotation period to be 30.5 ± 0.7 d using archival photometry and RVs. Transiting Exoplanet Survey Satellite (TESS) objects of Interest (TOI)-431 b is a super-Earth with a period of 0.49 d, a radius of 1.28 ± 0.04 R, a mass of 3.07 ± 0.35 M, and a density of 8.0 ± 1.0 g cm-3; TOI-431 d is a sub-Neptune with a period of 12.46 d, a radius of 3.29 ± 0.09 R, a mass of 9.90+1.53-1.49 M, and a density of 1.36 ± 0.25 g cm-3. We find a third planet, TOI-431 c, in the High Accuracy Radial velocity Planet Searcher RV data, but it is not seen to transit in the TESS light curves. It has an Msin i of 2.83+0.41-0.34 M, and a period of 4.85 d. TOI-431 d likely has an extended atmosphere and is one of the most well-suited TESS discoveries for atmospheric characterization, while the super-Earth TOI-431 b may be a stripped core. These planets straddle the radius gap, presenting an interesting case-study for atmospheric evolution, and TOI-431 b is a prime TESS discovery for the study of rocky planet phase curves.Fil: Osborn, Ares. University of Warwick; Reino UnidoFil: Armstrong, David J. University of Warwick; Reino UnidoFil: Cale, Bryson. George Mason University; Estados UnidosFil: Brahm, Rafael. Universidad Adolfo Ibañez; Chile. Instituto de AstrofĂsica; ChileFil: Wittenmyer, Robert A. University Of Southern Queensland; AustraliaFil: Dai, Fei. Division Of Geological And Planetary Sciences; Estados UnidosFil: Crossfield, Ian J. M. University of Kansas; Estados UnidosFil: Bryant, Edward M. University of Warwick; Reino UnidoFil: Adibekyan, Vardan. Universidad de Porto; PortugalFil: Cloutier, Ryan. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Collins, Karen A. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Delgado Mena, E.. Universidad de Porto; PortugalFil: Fridlund, Malcolm. Leiden University; PaĂses Bajos. Chalmers University of Technology; SueciaFil: Hellier, Coel. Keele University; Reino UnidoFil: Howell, Steve B. NASA Ames Research Center; Estados UnidosFil: King, George W. University of Warwick; Reino UnidoFil: Lillo Box, Jorge. Consejo Superior de Investigaciones CientĂficas. Centro de AstrobiologĂa; EspañaFil: Otegi, Jon. Universidad de Ginebra; Suiza. Universitat Zurich; SuizaFil: Sousa, S.. Universidad de Porto; PortugalFil: Stassun, Keivan G. Vanderbilt University; Estados UnidosFil: Matthews, Elisabeth C. Universidad de Ginebra; Suiza. Massachusetts Institute of Technology; Estados UnidosFil: Ziegler, Carl. University of Toronto; CanadĂĄFil: Ricker, George. Massachusetts Institute of Technology; Estados UnidosFil: Vanderspek, Roland. Massachusetts Institute of Technology; Estados UnidosFil: Latham, David W. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Seager, S.. Massachusetts Institute of Technology; Estados UnidosFil: Winn, Joshua N.. University of Princeton; Estados UnidosFil: Jenkins, Jon M. NASA Ames Research Center; Estados UnidosFil: Acton, Jack S. University of Leicester; Reino UnidoFil: Addison, Brett C. University Of Southern Queensland; AustraliaFil: Diaz, Rodrigo Fernando. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Ciencias FĂsicas. - Universidad Nacional de San MartĂn. Instituto de Ciencias FĂsicas; Argentin
TOI-1416: A system with a super-Earth planet with a 1.07d period
TOI 1416 (BD+42 2504, HIP 70705) is a V=10 late G or early K-type dwarf star
with transits detected by TESS. Radial velocities verify the presence of the
transiting planet TOI-1416 b, with a period of 1.07d, a mass of and a radius of , implying a slightly sub-Earth
density of g cm. The RV data also further indicate a tentative
planet c with a period of 27.4 or 29.5 days, whose nature cannot be verified
due to strong suspicions about contamination by a signal related to the Moon's
synodic period of 29.53 days. The near-USP (Ultra Short Period) planet TOI-1416
b is a typical representative of a short-period and hot ( 1570
K) super-Earth like planet. A planet model of an interior of molten magma
containing a significant fraction of dissolved water provides a plausible
explanation for its composition, and its atmosphere could be suitable for
transmission spectroscopy with JWST. The position of TOI-1416 b within the
radius-period distribution corroborates that USPs with periods of less than one
day do not form any special group of planets. Rather, this implies that USPs
belong to a continuous distribution of super-Earth like planets with periods
ranging from the shortest known ones up to ~ 30 days, whose period-radius
distribution is delimitated against larger radii by the Neptune desert and by
the period-radius valley that separates super-Earths from sub-Neptune planets.
In the abundance of small-short periodic planets against period, a plateau
between periods of 0.6 to 1.4 days has however become notable that is
compatible with the low-eccentricity formation channel. For the Neptune desert,
its lower limits required a revision due to the increasing population of short
period planets and new limits are provided. These limits are also given in
terms of the planets' insolation and effective temperatures.Comment: 31 pages, 31 figures, 8 tables, accepted for publication in A&
MicroRNA-22 and promoter motif polymorphisms at the Chga locus in genetic hypertension: functional and therapeutic implications for gene expression and the pathogenesis of hypertension
Hypertension is a common hereditary syndrome with unclear pathogenesis. Chromogranin A (Chga), which catalyzes formation and cargo storage of regulated secretory granules in neuroendocrine cells, contributes to blood pressure homeostasis centrally and peripherally. Elevated Chga occurs in spontaneously hypertensive rat (SHR) adrenal glands and plasma, but central expression is unexplored. In this report, we measured SHR and WistarâKyoto rat (control) Chga expression in central and peripheral nervous systems, and found Chga protein to be decreased in the SHR brainstem, yet increased in the adrenal and the plasma. By re-sequencing, we systematically identified five promoter, two coding and one 3âČ-untranslated region (3âČ-UTR) polymorphism at the SHR (versus WKY or BN) Chga locus. Using HXB/BXH recombinant inbred (RI) strain linkage and correlations, we demonstrated genetic determination of Chga expression in SHR, including a cis-quantitative trait loci (QTLs) (i.e. at the Chga locus), and such expression influenced biochemical determinants of blood pressure, including a cascade of catecholamine biosynthetic enzymes, catecholamines themselves and steroids. Luciferase reporter assays demonstrated that the 3âČ-UTR polymorphism (which disrupts a microRNA miR-22 motif) and promoter polymorphisms altered gene expression consistent with the decline in SHR central Chga expression. Coding region polymorphisms did not account for changes in Chga expression or function. Thus, we hypothesized that the 3âČ-UTR and promoter mutations lead to dysregulation (diminution) of Chga in brainstem cardiovascular control nuclei, ultimately contributing to the pathogenesis of hypertension in SHR. Accordingly, we demonstrated that in vivo administration of miR-22 antagomir to SHR causes substantial (âŒ18 mmHg) reductions in blood pressure, opening a novel therapeutic avenue for hypertension
Cyr61/CCN1 Displays High-Affinity Binding to the Somatomedin B 1â44 Domain of Vitronectin
OV) family of extracellular-associated (matricellular) proteins that present four distinct functional modules, namely insulin-like growth factor binding protein (IGFBP), von Willebrand factor type C (vWF), thrombospondin type 1 (TSP), and C-terminal growth factor cysteine knot (CT) domain. While heparin sulphate proteoglycans reportedly mediate the interaction of Cyr61 with the matrix and cell surface, the role of other extracellular associated proteins has not been revealed. at high concentrations attenuate Cyr61 binding to immobilized VTNC, while monomeric VTNC was ineffective. Therefore, immobilization of VTNC exposes cryptic epitopes that recognize Cyr61 with high affinity, as reported for a number of antibodies, ÎČ-endorphin, and other molecules. domain suggests that VTNC represent a point of anchorage for CCN family members to the matrix. Results are discussed in the context of the role of CCN and VTNC in matrix biology and angiogenesis
TOI-1416: A system with a super-Earth planet with a 1.07 d period
TOI-1416 (BD+42 2504, HIP 70705) is a V =10 late G- or early K-type dwarf star. TESS detected transits in its Sectors 16, 23, and 50 with a depth of about 455 ppm and a period of 1.07 days. Radial velocities (RVs) confirm the presence of the transiting planet TOI-1416 b, which has a mass of 3.48 ± 0.47 Mâą and a radius of 1.62 ± 0.08 Râą, implying a slightly sub-Earth density of 4.500.83+0.99 g cm3. The RV data also further indicate a tentative planet, c, with a period of 27.4 or 29.5 days, whose nature cannot be verified due to strong suspicions of contamination by a signal related to the Moon s synodic period of 29.53 days. The nearly ultra-short-period planet TOI-1416 b is a typical representative of a short-period and hot (Teq â 1570 K) super-Earth-like planet. A planet model of an interior of molten magma containing a significant fraction of dissolved water provides a plausible explanation for its composition, and its atmosphere could be suitable for transmission spectroscopy with JWST. The position of TOI-1416 b within the radius-period distribution corroborates the idea that planets with periods of less than one day do not form any special group. It instead implies that ultra-short-period planets belong to a continuous distribution of super-Earth-like planets with periods ranging from the shortest known ones up to â 30 days; their period-radius distribution is delimited against larger radii by the Neptune Desert and by the period-radius valley that separates super-Earths from sub-Neptune planets. In the abundance of small, short-periodic planets, a notable plateau has emerged between periods of 0.6- 1.4 days, which is compatible with the low-eccentricity formation channel. For the Neptune Desert, its lower limits required a revision due to the increasing population of short-period planets; for periods shorter then 2 days, we establish a radius of 1.6 Râą and a mass of 0.028 Mjup (corresponding to 8.9 Mâą) as the desert s lower limits. We also provide corresponding limits to the Neptune Desert against the planets insolation and effective temperatures
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