The excitation function for the fusion–evaporation reaction Si28+Ni64 has been measured down to a cross section of 25 nb. This is the first observation of fusion hindrance at extreme sub-barrier ...energies for a system with a small, negative Q-value (−1.78 MeV). This result is further proof that heavy-ion fusion hindrance, reported earlier only for systems with large, negative Q-values, is a general phenomenon. The measured behavior can be reproduced by coupled-channels calculations with a modified ion–ion potential incorporating the effects of nuclear incompressibility.
We report the discovery of a 61-Jupiter-mass brown dwarf (BD), which transits its F8V host star, WASP-30, every 4.16 days. From a range of age indicators we estimate the system age to be 1-2 Gyr. We ...derive a radius (0.89 ± 0.02 R Jup) for the companion that is consistent with that predicted (0.914 R Jup) by a model of a 1 Gyr old, non-irradiated BD with a dusty atmosphere. The location of WASP-30b in the minimum of the mass-radius relation is consistent with the quantitative prediction of Chabrier & Baraffe, thus confirming the theory.
Vertebrates have highly methylated genomes at CpG positions, whereas invertebrates have sparsely methylated genomes. This increase in methylation content is considered a major regulatory innovation ...of vertebrate genomes. However, here we report that a sponge, proposed as the potential sister group to the rest of animals, has a highly methylated genome. Despite major differences in genome size and architecture, we find similarities between the independent acquisitions of the hypermethylated state. Both lineages show genome-wide CpG depletion, conserved strong transcription factor methyl-sensitivity and developmental methylation dynamics at 5-hydroxymethylcytosine enriched regions. Together, our findings trace back patterns associated with DNA methylation in vertebrates to the early steps of animal evolution. Thus, the sponge methylome challenges previous hypotheses concerning the uniqueness of vertebrate genome hypermethylation and its implications for regulatory complexity.
Sensitivity of GRETINA position resolution to hole mobility Prasher, V.S.; Cromaz, M.; Merchan, E. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2017, Letnik:
846, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The sensitivity of the position resolution of the gamma-ray tracking array GRETINA to the hole charge-carrier mobility parameter is investigated. The χ2 results from a fit of averaged signal ...(“superpulse”) data exhibit a shallow minimum for hole mobilities 15% lower than the currently adopted values. Calibration data on position resolution is analyzed, together with simulations that isolate the hole mobility dependence of signal decomposition from other effects such as electronics cross-talk. The results effectively exclude hole mobility as a dominant parameter for improving the position resolution for reconstruction of gamma-ray interaction points in GRETINA.
Human breastmilk provides complete nutrition for infants and helps protect against certain childhood diseases. Despite this, rates of initiation of breastfeeding in the UK remain low relative to ...other countries. In 'Our healthier nation' action report, the government has highlighted the promotion of breastfeeding in order to assist improvements in health and to reduce the health inequalities of mothers and children in the UK.
The primary aim of this systematic review was to evaluate existing evidence to identify which promotion programmes are effective at increasing the number of women who start to breastfeed. In addition, the review aimed to assess the impact of such programmes on the duration and/or exclusivity of breastfeeding and the intermediate and process outcomes. Where the strength and quality of the evidence permitted, the review aimed to identify implications for practice within the UK and priority areas for future research.
A range of electronic databases were searched from inception to November 1998, several relevant journals were hand-searched, and references of retrieved papers were examined. Relevant experts, organisations and lay groups were contacted to help identify further published or unpublished material. Additionally, an expert panel was consulted.
Four types of criteria were used to select eligible studies for this review: STUDY DESIGN - randomised controlled trials (RCTs), non-RCTs with concurrent controls, and before-after studies (cohort or cross-sectional). PARTICIPANTS - pregnant women, mothers in the immediate postpartum period before the first breastfeed, any participant linked to pregnant women or new mothers, or any participant who may breastfeed in the future, or be linked to a breastfeeding woman in the future. INTERVENTIONS - any type of intervention designed to promote the uptake of breastfeeding was included; control groups could receive an alternative breastfeeding promotion programme or standard care. OUTCOMES - the primary outcome was initiation of breastfeeding; secondary outcomes (duration and exclusivity of breastfeeding) were included if initiation was reported in the same study; intermediate and process outcomes were also included, and need not necessarily be associated with reported initiation rates. DATA EXTRACTION AND VALIDITY ASSESSMENT: Data were extracted into structured tables. All included studies were checked against a comprehensive methodological checklist. Different checklists were used for RCTs, non-RCTs and before-after studies. Data extraction and validity assessment were independently checked by a second reviewer.
The studies were grouped according to intervention type, and were combined using a narrative synthesis. For individual RCTs and non-RCTs reporting initiation of breastfeeding, relative risks with associated 95% confidence intervals were estimated, with calculations performed on an intention-to-treat basis where possible. Pooling of relative risks was considered inappropriate owing to the lack of similarity across the studies.
A total of 59 studies met the selection criteria, comprising 14 RCTs, 16 non-RCTs and 29 before-after studies. Interventions were grouped into the following categories: health education, health sector initiatives (HSI) - general, HSI - Baby Friendly Hospital Initiative (BFHI), HSI - training of health professionals, HSI - US Department of Agriculture's Special Supplemental Nutrition Program for Women, Infants, and Children (WIC), HSI - social support from health professionals, peer support, media campaigns, multifaceted interventions. In many cases, studies were dissimilar in terms of the type of intervention(s), participants and the definitions of outcomes. Methodological problems of some studies also limited interpretation of findings. (ABSTRACT TRUNCATED)
The availability of crop specimens archived in herbaria and old seed collections represent valuable resources for the analysis of plant genetic diversity and crop domestication. The ability to ...extract ancient DNA (aDNA) from such samples has recently allowed molecular genetic investigations to be undertaken in ancient materials. While analyses of aDNA initially focused on the use of markers which occur in multiple copies such as the internal transcribed spacer region (ITS) within ribosomal DNA and those requiring amplification of short DNA regions of variable length such as simple sequence repeats (SSRs), emphasis is now moving towards the genotyping of single nucleotide polymorphisms (SNPs), traditionally undertaken in aDNA by Sanger sequencing. Here, using a panel of barley aDNA samples previously surveyed by Sanger sequencing for putative causative SNPs within the flowering-time genePPD-H1, we assess the utility of the Kompetitive Allele Specific PCR (KASP) genotyping platform for aDNA analysis. We find KASP to out-perform Sanger sequencing in the genotyping of aDNA samples (78% versus 61% success, respectively), as well as being robust to contamination. The small template size (≥46 bp) and one-step, closed-tube amplification/genotyping process make this platform ideally suited to the genotypic analysis of aDNA, a process which is often hampered by template DNA degradation and sample cross-contamination. Such attributes, as well as its flexibility of use and relatively low cost, make KASP particularly relevant to the genetic analysis of aDNA samples. Furthermore, KASP provides a common platform for the genotyping and analysis of corresponding SNPs in ancient, landrace and modern plant materials. The extended haplotype analysis ofPPD-H1undertaken here (allelic variation at which is thought to be important for the spread of domestication and local adaptation) provides further resolution to the previously identified geographic cline of flowering-time allele distribution, illustrating how KASP can be used to aid genetic analyses of aDNA from plant species. We further demonstrate the utility of KASP by genotyping ten additional genetic markers diagnostic for morphological traits in barley, shedding light on the phenotypic traits, alleles and allele combinations present in these unviable ancient specimens, as well as their geographic distributions.
The Horizon Europe project ISIDORe is dedicated to pandemic preparedness and responsiveness research. It brings together 17 research infrastructures (RIs) and networks to provide a broad range of ...services to infectious disease researchers. An efficient and structured treatment of data is central to ISIDORe’s aim to furnish seamless access to its multidisciplinary catalogue of services, and to ensure that users’ results are treated FAIRly. ISIDORe therefore requires a data management plan (DMP) covering both access management and research outputs, applicable over a broad range of disciplines, and compatible with the constraints and existing practices of its diverse partners.
Here, we describe how, to achieve that aim, we undertook an iterative, step-by-step, process to build a community-approved living document, identifying good practices and processes, on the basis of use cases, presented as proof of concepts. International fora such as the RDA and EOSC, and primarily the BY-COVID project, furnished registries, tools and online data platforms, as well as standards, and the support of data scientists. Together, these elements provide a path for building an umbrella, FAIR-compliant DMP, aligned as fully as possible with FAIR principles, which could also be applied as a framework for data management harmonisation in other large-scale, challenge-driven projects. Finally, we discuss how data management and reuse can be further improved through the use of knowledge models when writing DMPs and, how, in the future, an inter-RI network of data stewards could contribute to the establishment of a community of practice, to be integrated subsequently into planned trans-RI competence centres.
Abstract Centaurs are small solar system objects on chaotic orbits in the giant planet region, forming an evolutionary continuum with the Kuiper Belt objects and Jupiter-family comets. Some Centaurs ...are known to exhibit cometary activity, though unlike comets, this activity tends not to correlate with heliocentric distance, and the mechanism behind it is currently poorly understood. We utilize serendipitous observations from the Asteroid Terrestrial-impact Last Alert System, Zwicky Transient Facility, Panoramic Survey Telescope and Rapid Response System, Dark Energy Survey, and Gaia in addition to targeted follow-up observations from the Las Cumbres Observatory, TRAnsiting Planets and PlanetesImals Small Telescope South (TRAPPIST-South), and Gemini North telescope to analyze an unexpected brightening exhibited by the known active Centaur (2060) Chiron in 2021. This is highly indicative of a cometary outburst. As of 2023 February, Chiron had still not returned to its prebrightening magnitude. We find Chiron's rotational lightcurve, phase curve effects, and possible high-albedo surface features to be unlikely causes of this observed brightening. We consider the most likely cause to be an epoch of either new or increased cometary activity, though we cannot rule out a possible contribution from Chiron's reported ring system, such as a collision of as-yet-unseen satellites shepherding the rings. We find no evidence for a coma in our Gemini or TRAPPIST-South observations, though this does not preclude the possibility that Chiron is exhibiting a coma that is too faint for observation or constrained to the immediate vicinity of the nucleus.
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