15,971 research outputs found
Discovery and quantitative spectral analysis of an Ofpe/WN9 (WN11) star in the Sculptor spiral galaxy NGC 300
We have discovered an Ofpe/WN9 (WN11 following Smith et al.) star in the
Sculptor spiral galaxy NGC 300, the first object of this class found outside
the Local Group, during a recent spectroscopic survey of blue supergiant stars
obtained at the ESO VLT. The light curve over a five-month period in late 1999
displays a variability at the 0.1 mag level. The intermediate resolution
spectra (3800-7200 A) show a very close resemblance to the Galactic LBV AG Car
during minimum. We have performed a detailed non-LTE analysis of the stellar
spectrum, and have derived a chemical abundance pattern which includes H, He,
C, N, O, Al, Si and Fe, in addition to the stellar and wind parameters. The
derived stellar properties and the He and N surface enrichments are consistent
with those of other Local Group WN11 stars in the literature, suggesting a
similar quiescent or post-LBV evolutionary status.Comment: 9 pages, 4 figures, 2 tables. Accepted for publication in the
Astrophysical Journal Letter
Influence of Grazing on Soil Microbial Communities on a Mixed Grass Prairie Ecosystem
The grazing of ungulates is the predominant use for much of the world\u27s semiarid rangelands. Grazing these lands can result in significant changes not only in the vegetation community but also in the soil physical, chemical and biological properties. Changes in soil physical and chemical properties and the plant community can potentially lead to changes in soil microbial communities which may have long-term ramifications for nutrient cycling and carbon (C) sequestration. The objective of this research was to ascertain the influence of three long-term grazing treatments on soil microbial communities
Effect of Achromycin Ointment on Healing Following Periodontal Surgery
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141040/1/jper0368.pd
Feasibility trial of a psychoeducational intervention for parents with personality difficulties: the Helping Families Programme
The Helping Families Programme is a psychoeducational parenting intervention that aims to improve outcomes and engagement for parents affected by clinically significant personality difficulties. This is achieved by working collaboratively with parents to explore ways in which their emotional and relational difficulties impact on parenting and child functioning, and to identify meaningful and realistic goals for change. The intervention is delivered via one-to-one sessions at weekly intervals over a period of 16 weeks. This protocol describes a two arm parallel RCT in which consenting parents are randomly allocated in a 1:1 ratio to either the Helping Families Programme plus the usual services that the parent may be receiving from their mental health and/or social care providers, or to standard care (usual services plus a brief parenting advice session). The primary clinical outcome will be child behaviour. Secondary clinical outcomes will be child and parental mental health, parenting satisfaction, parenting behaviour and therapeutic alliance. Health economic measures will be collected on quality of life and service use. Outcome measures will be collected at the initial assessment stage, after the intervention is completed and at 6-month follow-up by research staff blind to group allocation. Trial feasibility will be assessed using rates of trial participation at the three time points and intervention uptake, attendance and retention.
A parallel process evaluation will use qualitative interviews to ascertain key-workers’ and parent participants' experiences of intervention delivery and trial participation. The results of this feasibility study will determine the appropriateness of proceeding to a full-scale trial
Removing Adverse Volumetric Effects From Trained Neural Radiance Fields
While the use of neural radiance fields (NeRFs) in different challenging
settings has been explored, only very recently have there been any
contributions that focus on the use of NeRF in foggy environments. We argue
that the traditional NeRF models are able to replicate scenes filled with fog
and propose a method to remove the fog when synthesizing novel views. By
calculating the global contrast of a scene, we can estimate a density threshold
that, when applied, removes all visible fog. This makes it possible to use NeRF
as a way of rendering clear views of objects of interest located in fog-filled
environments. Additionally, to benchmark performance on such scenes, we
introduce a new dataset that expands some of the original synthetic NeRF scenes
through the addition of fog and natural environments. The code, dataset, and
video results can be found on our project page: https://vegardskui.com/fognerf/Comment: This work has been submitted to the IEEE for possible publication.
Copyright may be transferred without notice, after which this version may no
longer be accessibl
Functional responses of methanogenic archaea to syntrophic growth.
Methanococcus maripaludis grown syntrophically with Desulfovibrio vulgaris was compared with M. maripaludis monocultures grown under hydrogen limitation using transcriptional, proteomic and metabolite analyses. These measurements indicate a decrease in transcript abundance for energy-consuming biosynthetic functions in syntrophically grown M. maripaludis, with an increase in transcript abundance for genes involved in the energy-generating central pathway for methanogenesis. Compared with growth in monoculture under hydrogen limitation, the response of paralogous genes, such as those coding for hydrogenases, often diverged, with transcripts of one variant increasing in relative abundance, whereas the other was little changed or significantly decreased in abundance. A common theme was an apparent increase in transcripts for functions using H(2) directly as reductant, versus those using the reduced deazaflavin (coenzyme F(420)). The greater importance of direct reduction by H(2) was supported by improved syntrophic growth of a deletion mutant in an F(420)-dependent dehydrogenase of M. maripaludis. These data suggest that paralogous genes enable the methanogen to adapt to changing substrate availability, sustaining it under environmental conditions that are often near the thermodynamic threshold for growth. Additionally, the discovery of interspecies alanine transfer adds another metabolic dimension to this environmentally relevant mutualism
Defining and Detecting Crossover-Interference Mutants in Yeast
The analysis of crossover interference in many creatures is complicated by the presence of two kinds of crossovers, interfering and noninterfering. In such creatures, the values of the traditional indicators of interference are subject not only to the strength of interference but also to the relative frequencies of crossing over contributed by the two kinds. We formalize the relationship among these variables and illustrate the possibilities and limitations of classical interference analysis with meiotic tetrad data from wild-type Saccharomyces cerevisiae and from mlh1 and ndj1 mutants
Randomised feasibility trial of the helping families programme-modified: an intensive parenting intervention for parents affected by severe personality difficulties
Background: Specialist parenting intervention could improve coexistent parenting and child mental health difficulties of parents affected by severe personality difficulties.
Objective: Conduct a feasibility trial of Helping Families Programme-Modified (HFP-M), a specialist parenting intervention.
Design: Pragmatic, mixed-methods trial, 1:1 random allocation, assessing feasibility, intervention acceptability and outcome estimates.
Settings: Two National Health Service health trusts and local authority children’s social care.
Participants: Parents: (i) primary caregiver, (ii) 18 to 65 years, (iii) severe personality difficulties, (iv) proficient English and (v) capacity for consent. Child: (i) 3 to 11 years, (ii) living with index parent and (iii) significant emotional/behavioural difficulties.
Intervention: HFP-M: 16-session home-based intervention using parenting and therapeutic engagement strategies. Usual care: standard care augmented by single psychoeducational parenting session.
Outcomes: Primary feasibility outcome: participant retention rate. Secondary outcomes: (i) rates of recruitment, eligibility and data completion, and (ii) rates of intervention acceptance, completion and alliance (Working Alliance Inventory-Short Revised). Primary clinical outcome: child behaviour (Eyberg Child Behaviour Inventory). Secondary outcomes: child mental health (Concerns About My Child, Child Behaviour Checklist-Internalising Scale), parenting (Arnold-O’Leary Parenting Scale, Kansas Parental Satisfaction Scale) and parent mental health (Symptom-Checklist-27). Quantitative data were collected blind to allocation.
Results: Findings broadly supported non-diagnostic selection criterion. Of 48 participants recruited, 32 completed post-intervention measures at mean 42 weeks later. Participant retention exceeded a priori rate (HFP-M=18; Usual care=14; 66.7%, 95% CI 51.6% to 79.6%). HFP-M was acceptable, with delivery longer than planned. Usual care had lower alliance rating. Child and parenting outcome effects detected across trial arms with potential HFP-M advantage (effect size range: 0.0 to 1.3).
Conclusion: HFP-M is an acceptable and potentially effective specialist parenting intervention. A definitive trial is feasible, subject to consideration of recruitment and retention methods, intervention efficiency and comparator condition. Caution is required in interpretation of results due to reduced sample size. No serious adverse events reported. Trial registration number: ISRCTN1457323
Impact of COVID-19 emergency on the psychological well-being of susceptible individuals
The current pandemic has exerted an unprecedented psychological impact on the world population, and its effects on mental health are a growing concern. The present study aims to evaluate psychological well-being (PWB) during the COVID-19 crisis in university workers with one or more diseases likely to increase the risk of severe outcomes in the event of SARS-CoV-2 infection, defined as susceptible. 210 susceptible employees of an Italian University (aged 25-71 years) were recruited during the COVID-19 second wave (October-December 2020). A group comprising 90 healthy university employees (aged 26-69 years) was also recruited. The self-report Psychological General Well Being Index (PGWBI) was used to assess global PWB and the influence on six sub-domains: anxiety, depressed mood, positive well-being, self-control, general health, and vitality. We applied non-linear dimension-reduction techniques and regression methods to 45 variables in order to assess the main demographic, occupational, and general-health-related factors predicting PWB during the COVID-19 crisis. PGWBI score was higher in susceptible than in healthy workers, both as total score (mean 77.8 vs 71.3) and across almost all subscales. Age and jobs involving high social interaction before the pandemic were inversely associated with the PWB total score, general health, and self-control subscores. The current data suggest no decline in PWB during the second wave of COVID-19 health emergency in susceptible individuals of working age. Critically, higher risk for mental-health issues appears to be inversely related to age, particularly among individuals deprived of their previous level of social interaction at work
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