2,771 research outputs found
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Determination of the Quadrupole Coupling Constant in the N^{14} Atomic Ground State
The zero-field hyperfine frequencies in the ground state of atomic N14 have been measured in a hydrogen maser with sufficient accuracy to resolve the quadrupole coupling constant B. The result is B=+1.32±0.20 Hz.Molecular and Cellular Biolog
Coral restoration in Old Providence Atoll, Seaflower MPA, after Beta Hurricane: a joint work among scientists, technicians and fishermen
A Substellar Companion in a 1.3 yr Nearly-circular Orbit of HD 16760
We report the detection of a substellar companion orbiting the G5 dwarf HD
16760 from the N2K sample. Precise Doppler measurements of the star from Subaru
and Keck revealed a Keplerian velocity variation with a period of 466.47+-0.35
d, a semiamplitude of 407.71+-0.84 m/s, and an eccentricity of 0.084+-0.003.
Adopting a stellar mass of 0.78+-0.05 M_Sun, we obtain a minimum mass for the
companion of 13.13+-0.56 M_JUP, which is close to the planet/brown-dwarf
transition, and the semimajor axis of 1.084+-0.023 AU. The nearly circular
orbit despite the large mass and intermediate orbital period makes this
companion unique among known substellar companions.Comment: 14 pages, 2 figures, accepted for publication in Ap
The California Planet Survey. I. Four New Giant Exoplanets
We present precise Doppler measurements of four stars obtained during the past decade at Keck Observatory by the California Planet Survey (CPS). These stars, namely, HD 34445, HD 126614, HD 13931, and Gl 179, all show evidence for a single planet in Keplerian motion. We also present Doppler measurements from the Hobby-Eberly Telescope (HET) for two of the stars, HD 34445 and Gl 179, that confirm the Keck detections and significantly refine the orbital parameters. These planets add to the statistical properties of giant planets orbiting near or beyond the ice line, and merit follow-up by astrometry, imaging, and space-borne spectroscopy. Their orbital parameters span wide ranges of planetary minimum mass (M sin i = 0.38-1.9 M(Jup)), orbital period (P = 2.87-11.5 yr), semimajor axis (a = 2.1-5.2 AU), and eccentricity (e = 0.02-0.41). HD 34445 b (P = 2.87 yr, M sin i = 0.79 MJup, e = 0.27) is a massive planet orbiting an old, G-type star. We announce a planet, HD 126614 Ab, and an M dwarf, HD 126614 B, orbiting the metal-rich star HD 126614 (which we now refer to as HD 126614 A). The planet, HD 126614 Ab, has minimum mass M sin i = 0.38 MJup and orbits the stellar primary with period P = 3.41 yr and orbital separation a = 2.3 AU. The faint M dwarf companion, HD 126614 B, is separated from the stellar primary by 489 mas (33 AU) and was discovered with direct observations using adaptive optics and the PHARO camera at Palomar Observatory. The stellar primary in this new system, HD 126614 A, has the highest measured metallicity ([ Fe/ H] = + 0.56) of any known planet-bearing star. HD 13931 b (P = 11.5 yr, M sin i = 1.88 MJup, e = 0.02) is a Jupiter analog orbiting a near solar twin. Gl 179 b (P = 6.3 yr, M sin i = 0.82 M(Jup), e = 0.21) is a massive planet orbiting a faint M dwarf. The high metallicity of Gl 179 is consistent with the planet-metallicity correlation among M dwarfs, as documented recently by Johnson & Apps.NSF AST-0702821NASA NNX06AH52GMcDonald Observator
Impact of Parental Mental Health and Poverty on the Health of the Next Generation: A Multi-Trajectory Analysis Using the UK Millennium Cohort Study
The Intermediate Filament Cytoskeleton of Macrophages
This study characterizes two-and three-dimensional ultrastructure and surface topography of polymerized networks of intermediate filaments (IF) isolated from mouse peritoneal macrophages. Isolated IF bound to monoclonal anti-IF antibodies in enzyme-linked immunosorbent assays. Immunogold labeling of IF with specific antibodies revealed that epitopes are distributed along filaments particularly at junctions where filaments interconnect. Networks of IF, viewed by scanning electron microscopy, organized as ropelike groups of interconnecting filaments which swirl and encircle each other to form three-dimensional lattices containing ellipsoidal-, circular-, and vacuole-shaped cavities. Cavity diameters were similar in size to organelles and vacuoles; diameters were grouped as small (12-288 nm), medium (0.3-1.7 μm), and large (2-3 μm). The walls of the cavities appeared as beaded structures with alternating globular and linear regions. Linear regions were 14 nm. Repeat distances taken from the central axis of globular regions were 23-27 nm. The lattice organization of IF observed in vitro was similar to images seen in vivo in Triton-insoluble cytoskeletons immunofluorescently labeled with specific antibodies. In whole cells processed for TEM, swirling bundles of IF were found encircling membranous vacuoles. Based on the lattice architecture of IF, cavity dimensions, and IF location, we postulate that intermediate filaments may function in the mechanical and spatial distribution of vacuoles in the cell cytoplasm
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Lack of Association Between 25(OH)D Levels and Incident Type 2 Diabetes in Older Women
Objective: To examine whether lower serum levels of serum 25-hydroxyvitamin (OH) D [25(OH)D] are associated with increased risk of developing type 2 diabetes. Research Design and Methods: A post hoc analysis of three nested case-control studies of fractures, colon cancer, and breast cancer that measured serum 25(OH)D levels in women participating in the Women’s Health Initiative (WHI) Clinical Trials and Observational Study who were free of prevalent diabetes at baseline. Diabetes was defined as self-report of physician diagnosis or receiving insulin or oral hypoglycemic medication. We used inverse probability weighting to make the study population representative of the WHI population as a whole. Weighted logistic regression models compared 25(OH)D levels (divided into quartiles, clinical cut points [<50, 50–<75, 75 nmol/L], or as a continuous variable) using the distribution of control subjects and adjusted for multiple confounding factors. Results: Of 5,140 women (mean age 66 years) followed for an average of 7.3 years, 317 (6.2%) developed diabetes. Regardless of the cut points used or as a continuous variable, 25(OH)D levels were not associated with diabetes incidence in either age or fully adjusted models. Nor was any relationship found between 25(OH)D and incident diabetes when evaluated by strata of BMI, race/ethnicity, or randomization status in the Calcium Vitamin D trial. Conclusions: Lower serum 25(OH)D levels were not associated with increased risk of developing type 2 diabetes in this racially and ethnically diverse population of postmenopausal women
Embedding clinical interventions into observational studies
Novel approaches to observational studies and clinical trials could improve the cost-effectiveness and speed of translation of research. Hybrid designs that combine elements of clinical trials with observational registries or cohort studies should be considered as part of a long-term strategy to transform clinical trials and epidemiology, adapting to the opportunities of big data and the challenges of constrained budgets. Important considerations include study aims, timing, breadth and depth of the existing infrastructure that can be leveraged, participant burden, likely participation rate and available sample size in the cohort, required sample size for the trial, and investigator expertise. Community engagement and stakeholder (including study participants) support are essential for these efforts to succeed
Delivering McJustice? The Probation Factory at the Magistrates’ Court
Despite playing a pivotal role in thousands of defendants’ experiences of criminal justice every year, the role of probation workers in the English and Welsh Magistrates’ courts has been neglected by researchers for several decades. This article presents the findings of an ethnographic study of the work of probation staff in two such courts. The study suggests that probation work in this context is being squeezed into an operating model which bears all the hallmarks of a process described by Ritzer as ‘McDonaldization’. It is argued that the proximate causes of McDonaldization in this sub-field of probation work lie at the intersection of parallel Government-led reform programmes – Transforming Rehabilitation and Transforming Justice – which have respectively focused on creating a market for probation services and enhancing the administrative efficiency of criminal proceedings. Until now, almost no attention has been paid, either by researchers or policy-makers, to the intersection of these programmes of reform in the probation suites at the Magistrates’ courts
Radium contamination in the area around Dalgety Bay
In this report, the Committee on Medical Aspects of Radiation in the Environment (COMARE) presents a comprehensive review of the radium contamination in the area around Dalgety Bay. This report covers the history of the site, the type and extent of the contamination, the recent investigations and the cancer epidemiology for the area. The report also considers the implications for other similarly contaminated sites
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