538 research outputs found
Modelling stellar evolution in mass-transferring binaries and gravitational-wave progenitors with METISSE
Massive binaries are vital sources of various transient processes, including
gravitational-wave mergers. However, large uncertainties in the evolution of
massive stars, both physical and numerical, present a major challenge to the
understanding of their binary evolution. In this paper, we upgrade our
interpolation-based stellar evolution code METISSE to include the effects of
mass changes, such as binary mass transfer or wind-driven mass loss, not
already included within the input stellar tracks. METISSE's implementation of
mass loss (applied to tracks without mass loss) shows excellent agreement with
the SSE fitting formulae and with detailed MESA tracks, except in cases where
the mass transfer is too rapid for the star to maintain equilibrium. We use
this updated version of METISSE within the binary population synthesis code BSE
to demonstrate the impact of varying stellar evolution parameters, particularly
core overshooting, on the evolution of a massive (25M and 15M)
binary system with an orbital period of 1800 days. Depending on the input
tracks, we find that the binary system can form a binary black hole or a black
hole-neutron star system, with primary(secondary) remnant masses ranging
between 4.47(1.36)M and 12.30(10.89)M, and orbital periods
ranging from 6 days to the binary becoming unbound. Extending this analysis to
a population of isolated binaries uniformly distributed in mass and orbital
period, we show that the input stellar models play an important role in
determining which regions of the binary parameter space can produce compact
binary mergers, paving the way for predictions for current and future
gravitational-wave observatories.Comment: 19 pages, 14 figures, accepted for publication in MNRA
Failure of interpolation in the intuitionistic logic of constant domains
This paper shows that the interpolation theorem fails in the intuitionistic
logic of constant domains. This result refutes two previously published claims
that the interpolation property holds.Comment: 13 pages, 0 figures. Overlaps with arXiv 1202.1195 removed, the text
thouroughly reworked in terms of notation and style, historical notes as well
as some other minor details adde
Whey protein consumption after resistance exercise reduces energy intake at a post-exercise meal
Purpose - Protein consumption after resistance exercise potentiates muscle protein synthesis, but its effects on subsequent appetite in this context are unknown. This study examined appetite and energy intake following consumption of protein- and carbohydrate-containing drinks after resistance exercise.
Methods - After familiarisation, 15 resistance training males (age 21 ± 1 years, body mass 78.0 ± 11.9 kg, stature 1.78 ± 0.07 m) completed two randomised, double-blind trials, consisting of lower-body resistance exercise, followed by consumption of a whey protein (PRO 23.9 ± 3.6 g protein) or dextrose (CHO 26.5 ± 3.8 g carbohydrate) drink in the 5 min post-exercise. An ad libitum meal was served 60 min later, with subjective appetite measured throughout. Drinks were flavoured and matched for energy content and volume. The PRO drink provided 0.3 g/kg body mass protein.
Results - Ad libitum energy intake (PRO 3742 ± 994 kJ; CHO 4172 ± 1132 kJ; P = 0.007) and mean eating rate (PRO 339 ± 102 kJ/min; CHO 405 ± 154 kJ/min; P = 0.009) were lower during PRO. The change in eating rate was associated with the change in energy intake (R = 0.661, P = 0.007). No interaction effects were observed for subjective measures of appetite. The PRO drink was perceived as creamier and thicker, and less pleasant, sweet and refreshing (P < 0.05).
Conclusion - These results suggest whey protein consumption after resistance exercise reduces subsequent energy intake, and this might be partially mediated by a reduced eating rate. Whilst this reduced energy intake is unlikely to impair hypertrophy, it may be of value in supporting an energy deficit for weight loss
A general role for TANGO1, encoded by MIA3, in secretory pathway organization and function
Complex machinery is required to drive secretory cargo export from the endoplasmic reticulum (ER), which is an essential process in eukaryotic cells. In vertebrates, the MIA3 gene encodes two major forms of transport and Golgi organization protein 1 (TANGO1S and TANGO1L), which have previously been implicated in selective trafficking of procollagen. Using genome engineering of human cells, light microscopy, secretion assays, genomics and proteomics, we show that disruption of the longer form, TANGO1L, results in relatively minor defects in secretory pathway organization and function, including having limited impacts on procollagen secretion. In contrast, loss of both long and short forms results in major defects in cell organization and secretion. These include a failure to maintain the localization of ERGIC53 (also known as LMAN1) and SURF4 to the ER–Golgi intermediate compartment and dramatic changes to the ultrastructure of the ER–Golgi interface. Disruption of TANGO1 causes significant changes in early secretory pathway gene and protein expression, and impairs secretion not only of large proteins, but of all types of secretory cargo, including small soluble proteins. Our data support a general role for MIA3/TANGO1 in maintaining secretory pathway structure and function in vertebrate cells
Normalization of drug and therapeutic concepts with Thera-Py
OBJECTIVE: The diversity of nomenclature and naming strategies makes therapeutic terminology difficult to manage and harmonize. As the number and complexity of available therapeutic ontologies continues to increase, the need for harmonized cross-resource mappings is becoming increasingly apparent. This study creates harmonized concept mappings that enable the linking together of like-concepts despite source-dependent differences in data structure or semantic representation.
MATERIALS AND METHODS: For this study, we created Thera-Py, a Python package and web API that constructs searchable concepts for drugs and therapeutic terminologies using 9 public resources and thesauri. By using a directed graph approach, Thera-Py captures commonly used aliases, trade names, annotations, and associations for any given therapeutic and combines them under a single concept record.
RESULTS: We highlight the creation of 16 069 unique merged therapeutic concepts from 9 distinct sources using Thera-Py and observe an increase in overlap of therapeutic concepts in 2 or more knowledge bases after harmonization using Thera-Py (9.8%-41.8%).
CONCLUSION: We observe that Thera-Py tends to normalize therapeutic concepts to their underlying active ingredients (excluding nondrug therapeutics, eg, radiation therapy, biologics), and unifies all available descriptors regardless of ontological origin
Identification of molecular markers of delayed graft function based on the regulation of biological ageing
Introduction:
Delayed graft function is a prevalent clinical problem in renal transplantation for which there is no objective system to predict occurrence in advance. It can result in a significant increase in the necessity for hospitalisation post-transplant and is a significant risk factor for other post-transplant complications.
Methodology:
The importance of microRNAs (miRNAs), a specific subclass of small RNA, have been clearly demonstrated to influence many pathways in health and disease. To investigate the influence of miRNAs on renal allograft performance post-transplant, the expression of a panel of miRNAs in pre-transplant renal biopsies was measured using qPCR. Expression was then related to clinical parameters and outcomes in two independent renal transplant cohorts.
Results:
Here we demonstrate, in two independent cohorts of pre-implantation human renal allograft biopsies, that a novel pre-transplant renal performance scoring system (GRPSS), can determine the occurrence of DGF with a high sensitivity (>90%) and specificity (>60%) for donor allografts pre-transplant, using just three senescence associated microRNAs combined with donor age and type of organ donation.
Conclusion:
These results demonstrate a relationship between pre-transplant microRNA expression levels, cellular biological ageing pathways and clinical outcomes for renal transplantation. They provide for a simple, rapid quantitative molecular pre-transplant assay to determine post-transplant allograft function and scope for future intervention. Furthermore, these results demonstrate the involvement of senescence pathways in ischaemic injury during the organ transplantation process and an indication of accelerated bio-ageing as a consequence of both warm and cold ischaemia
Comparing supermarket loyalty card data with traditional diet survey data for understanding how protein is purchased and consumed in older adults for the UK, 2014-16
The project was funded by the Research Councils UK ‘Priming Food Partnerships’ initiative supported by BBSRC, MRC, EPSRC and ESRC. Project reference number – BB/P023886/1. Thank you to the High Street Retailer for supplying the data.Peer reviewedPublisher PD
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Right Turn Veteran-Specific Recovery Service: 5 site evaluation pilot: Interim report
The Right Turn project works with the ex-service personnel community in recovery from substance misuse. This report presents the interim findings from a two-year evaluation on the impact on health and wellbeing outcomes on military veterans engaging in this innovative peer-focussed recovery service. The evaluation is designed around a structured quantitative data collection process using an established repeat measure design and utilises qualitative methodologies to explore both the life experiences of this veteran cohort and to take account of their own perceptions of the model of services they feel they require. This report suggests that the military veteran community experience distinct barriers to accessing main stream health and wellbeing services. Alongside comorbidity issues, management of chronic physical conditions and social isolation, this report demonstrates that this cohort's own previous military conditioning forms a further barrier to accessing support services. This report contains recommendations to inform generic support staff when encountering veterans within health and wellbeing settings
Right Turn Veteran-Specific Recovery Service: 5 site evaluation pilot : Interim report
The Right Turn project works with the ex-service personnel community in recovery from substance misuse. This report presents the interim findings from a two-year evaluation on the impact on health and wellbeing outcomes on military veterans engaging in this innovative peer-focussed recovery service. The evaluation is designed around a structured quantitative data collection process using an established repeat measure design and utilises qualitative methodologies to explore both the life experiences of this veteran cohort and to take account of their own perceptions of the model of services they feel they require.
This report suggests that the military veteran community experience distinct barriers to accessing main stream health and wellbeing services. Alongside comorbidity issues, management of chronic physical conditions and social isolation, this report demonstrates that this cohort's own previous military conditioning forms a further barrier to accessing support services. This report contains recommendations to inform generic support staff when encountering veterans within health and wellbeing settings
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