265 research outputs found
Identity Salience and Involvement among Resident and Nonresident Fathers
The literature on father involvement suggests that the value men ascribe to the father role is important for understanding their involvement with their children, yet this theory has received only limited empirical attention. Using data from the Fragile Families and Child Wellbeing Study (N = 3,554), I examined the association between fathers? identity salience reported at their child?s birth and their involvement (accessibility, engagement, and responsibility) when their child was about 1, 3, and 5 years old, carefully considering the role played by fathers? residence status. I found that fathers? identity salience predicted future levels of engagement net of a large number of fathers? characteristics, and that fathers with high identity salience were more likely to reside with their child, which facilitated their involvement. These results suggest that programs designed to enhance the salience of the father role would be useful for teaching men to become more involved fathers.Fatherhood, Fragile Families and Child Wellbeing (FFCW), Longitudinal Data, Parental Involvement, Social Psychology (Family)
Existence of spinning solitons in gauge field theory
We study the existence of classical soliton solutions with intrinsic angular
momentum in Yang-Mills-Higgs theory with a compact gauge group in
(3+1)-dimensional Minkowski space. We show that for \textit{symmetric} gauge
fields the Noether charges corresponding to \textit{rigid} spatial symmetries,
as the angular momentum, can be expressed in terms of \textit{surface}
integrals. Using this result, we demonstrate in the case of
the nonexistence of stationary and axially symmetric spinning excitations for
all known topological solitons in the one-soliton sector, that is, for 't
Hooft--Polyakov monopoles, Julia-Zee dyons, sphalerons, and also vortices.Comment: 21 pages, to appear in Phys.Rev.
Elastin-specific MRI of extracellular matrix-remodelling following hepatic radiofrequency-ablation in a VX2 liver tumor model
Hepatic radiofrequency ablation (RFA) induces a drastic alteration of the biomechanical environment in the peritumoral liver tissue. The resulting increase in matrix stiffness has been shown to significantly influence carcinogenesis and cancer progression after focal RF ablation. To investigate the potential of an elastin-specific MR agent (ESMA) for the assessment of extracellular matrix (ECM) remodeling in the periablational rim following RFA in a VX2 rabbit liver tumor-model, twelve New-Zealand-White-rabbits were implanted in the left liver lobe with VX2 tumor chunks from donor animals. RFA of tumors was performed using a perfused RF needle-applicator with a mean tip temperature of 70 degrees C. Animals were randomized into four groups for MR imaging and scanned at four different time points following RFA (week 0 [baseline], week 1, week 2 and week 3 after RFA), followed by sacrifice and histopathological analysis. ESMA-enhanced MR imaging was used to assess ECM remodeling. Gadobutrol was used as a third-space control agent. Molecular MR imaging using an elastin-specific probe demonstrated a progressive increase in contrast-to-noise ratio (CNR) (week 3: ESMA: 28.1 +/- 6.0; gadobutrol: 3.5 +/- 2.0), enabling non-invasive imaging of the peritumoral zone with high spatial-resolution, and accurate assessment of elastin deposition in the periablational rim. In vivo CNR correlated with ex vivo histomorphometry (ElasticaVanGiesson-stain, y=1.2x - 1.8, R-2=0.89, p<0.05) and gadolinium concentrations at inductively coupled mass spectroscopy (ICP-MS, y=0.04x+1.2, R-2=0.95, p<0.05). Laser-ICP-MS confirmed colocalization of elastin-specific probe with elastic fibers. Following thermal ablation, molecular imaging using an elastin-specific MR probe is feasible and provides a quantifiable biomarker for the assessment of the ablation-induced remodeling of the ECM in the periablational rim
Affine Gravity, Palatini Formalism and Charges
Affine gravity and the Palatini formalism contribute both to produce a simple
and unique formula for calculating charges at spatial and null infinity for
Lovelock type Lagrangians whose variational derivatives do not depend on
second-order derivatives of the field components. The method is based on the
covariant generalization due to Julia and Silva of the Regge-Teitelboim
procedure that was used to define properly the mass in the classical
formulation of Einstein's theory of gravity. Numerous applications reproduce
standard results obtained by other secure but mostly specialized methods. As a
novel application we calculate the Bondi energy loss in five dimensional
gravity, based on the asymptotic solution given by Tanabe, Tanahashi and
Shiromizu, and obtain, as expected, the same result. We also give the
superpotential for Einstein-Gauss-Bonnet gravity and find the superpotential
for Lovelock theories of gravity when the number of dimensions tends to
infinity with maximally symmetrical boundaries. The paper is written in
standard component formalism.Comment: The work is dedicated to Joshua Goldberg from whom I learned and got
interested in conservation laws in General Relativity (J.K
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Associations between Age, Years in Post, Years in the Profession and Personal Experience of Mental Health Problems in UK Mental Health Nurses
Nurses' mental health is of paramount importance, both in terms of patient safety and the sustainability of the workforce. Age, years in the profession, in post and personal experience or exposure to mental health problems are relevant to the mental health nursing workforce crisis in the United Kingdom. This study aimed to determine the relationship between age, years in the profession and post and self-reported experience of mental health problems using an online cross-sectional survey of 225 UK mental health nurses. Number of years in post was inversely correlated with overall experience of mental health problems, particularly living with someone else with mental health problems. Those with experience of living with someone with mental health problems had significantly fewer years of professional experience than those without. This article discusses possible explanations for this phenomenon and makes the case for future research on the topic
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Results of the third Marine Ice Sheet Model Intercomparison Project (MISMIP+)
We present the result of the third Marine Ice Sheet Model Intercomparison Project, MISMIP+. MISMIP+ is intended to be a benchmark for ice-flow models which include fast sliding marine ice streams and floating ice shelves and in particular a treatment of viscous stress that is sufficient to model buttressing, where upstream ice flow is restrained by a downstream ice shelf. A set of idealized experiments first tests that models are able to maintain a steady state with the grounding line located on a retrograde slope due to buttressing and then explore scenarios where a reduction in that buttressing causes ice stream acceleration, thinning, and grounding line retreat. The majority of participating models passed the first test and then produced similar responses to the loss of buttressing. We find that the most important distinction between models in this particular type of simulation is in the treatment of sliding at the bed, with other distinctions - notably the difference between the simpler and more complete treatments of englacial stress but also the differences between numerical methods - taking a secondary role. © 2020 Wolters Kluwer Medknow Publications. All rights reserved
Results of the third Marine Ice Sheet Model Intercomparison Project (MISMIP+)
We present the result of the third Marine Ice Sheet Model Intercomparison Project, MISMIP+. MISMIP+ is intended to be a benchmark for ice-flow models which include fast sliding marine ice streams and floating ice shelves and in particular a treatment of viscous stress that is sufficient to model buttressing, where upstream ice flow is restrained by a downstream ice shelf. A set of idealized experiments first tests that models are able to maintain a steady state with the grounding line located on a retrograde slope due to buttressing and then explore scenarios where a reduction in that buttressing causes ice stream acceleration, thinning, and grounding line retreat. The majority of participating models passed the first test and then produced similar responses to the loss of buttressing. We find that the most important distinction between models in this particular type of simulation is in the treatment of sliding at the bed, with other distinctions â notably the difference between the simpler and more complete treatments of englacial stress but also the differences between numerical methods â taking a secondary role
Evaluating Visual Acuity in the American Academy of Ophthalmology IRISÂź Registry
OBJECTIVE: To describe visual acuity data representation in the American Academy of Ophthalmology Intelligent Research in Sight (IRIS) Registry and present a data-cleaning strategy.
DESIGN: Reliability and validity study.
PARTICIPANTS: Patients with visual acuity records from 2018 in the IRIS Registry.
METHODS: Visual acuity measurements and metadata were identified and characterized from 2018 IRIS Registry records. Metadata, including laterality, assessment method (distance, near, and unspecified), correction (corrected, uncorrected, and unspecified), and flags for refraction or pinhole assessment were compared between Rome (frozen April 20, 2020) and Chicago (frozen December 24, 2021) versions. We developed a data-cleaning strategy to infer patients\u27 corrected distance visual acuity in their better-seeing eye.
MAIN OUTCOME MEASURES: Visual acuity data characteristics in the IRIS Registry.
RESULTS: The IRIS Registry Chicago data set contains 168 920 049 visual acuity records among 23 001 531 unique patients and 49 968 974 unique patient visit dates in 2018. Visual acuity records were associated with refraction in 5.3% of cases, and with pinhole in 11.0%. Mean (standard deviation) of all measurements was 0.26 (0.41) logarithm of the minimum angle of resolution (logMAR), with a range of - 0.3 to 4.0 A plurality of visual acuity records were labeled corrected (corrected visual acuity [CVA], 39.1%), followed by unspecified (37.6%) and uncorrected (uncorrected visual acuity [UCVA], 23.4%). Corrected visual acuity measurements were paradoxically worse than same day UCVA 15% of the time. In aggregate, mean and median values were similar for CVA and unspecified visual acuity. Most visual acuity measurements were at distance (59.8%, vs. 32.1% unspecified and 8.2% near). Rome contained more duplicate visual acuity records than Chicago (10.8% vs. 1.4%). Near visual acuity was classified with Jaeger notation and (in Chicago only) also assigned logMAR values by Verana Health. LogMAR values for hand motion and light perception visual acuity were lower in Chicago than in Rome. The impact of data entry errors or outliers on analyses may be reduced by filtering and averaging visual acuity per eye over time.
CONCLUSIONS: The IRIS Registry includes similar visual acuity metadata in Rome and Chicago. Although fewer duplicate records were found in Chicago, both versions include duplicate and atypical measurements (i.e., CVA worse than UCVA on the same day). Analyses may benefit from using algorithms to filter outliers and average visual acuity measurements over time.
FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found found in the Footnotes and Disclosures at the end of this article
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