Faddeev calculations for the A=5,6 Lambda-Lambda hypernuclei

Faddev calculations are reported for Lambda-Lambda-5H, Lambda-Lambda-5He and Lambda-Lambda-6He in terms of two Lambda hyperons plus the respective nuclear clusters, using Lambda-Lambda central potentials considered in past non-Faddeev calculations of Lambda-Lambda-6He. The convergence with respect to the partial-wave expansion is studied, and comparison is made with some of these Lambda-Lambda hypernuclear calculations. The Lambda-Lambda Xi-N mixing effect is briefly discussed.Comment: submitted for publicatio

Three-stage lipid dynamics during development of planktotrophic echinoderm larvae

Published November 16The eggs of marine species with planktotrophic development must contain, at a minimum, sufficient material for production of a larva that can then sequester additional materials to grow and metamorphose successfully. In echinoderms, lipids perform crucial energy storage and structural functions during larval construction, but their roles during later development and metamorphosis are poorly understood. We investigated lipid-class depletion in early development and accumulation in late development and a lipid nutritional condition index (energetic lipid:sterol ratio) from the egg to the juvenile in the sea star Patiriella regularis and the sea urchin Heliocidaris tuberculata. Three phases were identified: (1) rapid depletion of energetic lipids during embryogenesis and the facultative feeding period (between feeding competence and exhaustion of energetic lipid reserves), (2) larval growth with no improvement in lipid nutritional condition, and (3) rapid lipid accumulation in advanced larvae prior to metamorphosis. Maternally derived energetic lipids were depleted more slowly in fed than unfed larvae but were still exhausted quickly. Patiriella regularis improved their lipid condition index during Phase 3 by accumulating energetic lipid (triacylglycerol [TAG], diacylglycerol ether [DAGE]) reserves that were then partially used to fuel settlement and metamorphosis. In contrast, Heliocidaris tuberculata did not accumulate TAG or DAGE during this phase, suggesting that metamorphosis is fuelled by other reserves, which we hypothesize may be phospholipids.Thomas A. A. Prowse, Mary A. Sewell, Maria Byrn

A comparison of the nursing competence of graduates and diplomates from UK nursing programmes

This paper reviews the literature on nursing competence measurement and reports the results of a comparative quantitative study of the competencies of Project 2000 diplomates and BA (Hons) Adult Nursing graduates from two UK nursing programmes. The findings reveal that graduates appear to overcome any initial limitations and become more competent than the diplomates in certain areas. Attention to social awareness and participation is necessary in both pre-registration programmes, whilst greater attention could be given to graduates' leadership and management development. Diplomates need support in their professional development if they are to achieve the same level of competence as graduates during the first post-qualifying year. There are implications for the level of support afforded to qualifying nurses in their first staff positions; preceptorship programmes could be an important means of assisting newly qualified staff to gain confidence. More research on nurse competencies with larger samples drawn from programmes across the UK is needed

Nurse teachers' constructions of reflection and reflective practice

This article concerns the meanings that a sample of nurse teachers ascribed to the concepts of reflection and reflective practice as aspects of an undergraduate nursing curriculum. It represents one of the major findings in a qualitative study that set out to explore nurse teachers’ perceptions and experiences of using reflection with diploma nursing students in the Republic of Ireland. Eleven nurse teachers were interviewed intensively, and data were analysed using a strategy resembling grounded theory. Two major themes were identified: reflection and reflective practice as a way of reviewing clinical experiences, and reflection and reflective practice as a way of valuing, developing and professionalising nursing practice knowledge. There was evidence that reflective practice was compartmentalised on nursing curricula, and some participants reported having limited knowledge of reflection. A number of participants alluded to the potential for reflective practice to uncover the hidden wealth of knowledge in everyday nursing practice. There appeared, however, to be a risk that this perceived wealth may be a conceptualisation of the teachers, rather than the students. Reflective learning through the affective domain was perceived as central to caring.AMS. No Keywords

Author Correction: Effects of sampling effort on biodiversity patterns estimated from environmental DNA metabarcoding surveys (Scientific Reports, (2018), 8, 1, (8843), 10.1038/s41598-018-27048-2)

10.1038/s41598-019-43804-4Scientific Reports911589

The interaction and decay of K--mesons in photographic emulsion - Part III

This paper presents Part III of the series on the interaction of K--mesons in photographic emulsions contributed by the European K-collaboration. The mean free path for K--interaction in flight (10÷80) MeV with hydrogen and with the complex nuclei in emulsion are compared with other recent experimental data. A number of Σ-hyperons are also investigated. From favourable examples of Σ+-p decay recorded in the emulsion the Σ+ mass is estimated as MΣ=2327.2±1.0 mc and from the hydrogen capture (K-+H) events the mass difference (MΣ--MΣ+) is found to be 14.6±1.1 me. Lifetime estimates are also given for the charged Σ hypersons:a) The best estimate for the Σ+ lifetime is obtained using only events in which the decay proton is emitted forward in the centre-of-mass system. Thus τ+=0.82-0.20+0.34·10-10 s. b) A representative value for the hypothetical Σ- lifetime as determined from 70 selected Σπ± decays is 0.71-0.12+0.19·10-10 s. The effective lifetime appears (as well as can be ascertained) to remain of the order of the Σ;+ lifetime, even in samples containing widely different proportions of Σ- hyperons. Although values are greater than the lifetimes previously reported in emulsion esperiments, it still appears possible that a genuine anomaly may exist. The observed numbers of secondary interactions by charged particles emitted from the K--capture stars may be accounted for on the basis of proton interactions, although some contribution from deuterons is not excluded. One definite example of a fast Σ interaction (visible energy release 129 MeV) has been found in a length of 70 cm of track registered in the emulsion. The number of single scatterings in 18 cm of Σ- and 25 cm of Σ+ hyperon track in emulsion (energy interval (5÷100) MeV) are compared with that expected for Coulomb scattering by a point nucleus. Only a slight possible indication of the nuclear interaction of the Σ--hyperon is demonstrated with the few data at present available. In K--interactions giving (Σ+π) some 45 Σp+ and 47 Σπ+ decays were also examined for possible polarization of the decay with respect to the (Σ, π) plane of production. © 1960 Società Italiana di Fisica.SCOPUS: ar.jinfo:eu-repo/semantics/publishe