2,371 research outputs found
Colour preferences of UK garden birds at supplementary seed feeders
Supplementary feeding of garden birds generally has benefits for both bird populations and human wellbeing. Birds have excellent colour vision, and show preferences for food items of particular colours, but research into colour preferences associated with artificial feeders is limited to hummingbirds. Here, we investigated the colour preferences of common UK garden birds foraging at seed-dispensing artificial feeders containing identical food. We presented birds simultaneously with an array of eight differently coloured feeders, and recorded the number of visits made to each colour over 370 30-minute observation periods in the winter of 2014/15. In addition, we surveyed visitors to a garden centre and science festival to determine the colour preferences of likely purchasers of seed feeders. Our results suggest that silver and green feeders were visited by higher numbers of individuals of several common garden bird species, while red and yellow feeders received fewer visits. In contrast, people preferred red, yellow, blue and green feeders. We suggest that green feeders may be simultaneously marketable and attractive to foraging birds
Student perceptions of their autonomy at University
Ā© 2017, The Author(s). Learner autonomy is a primary learning outcome of Higher Education in many countries. However, empirical evaluation of how student autonomy progresses during undergraduate degrees is limited. We surveyed a total of 636 studentsā self-perceived autonomy during a period of two academic years using the Autonomous Learning Scale. Our analysis suggests that students do not perceive themselves as being any more autonomous as they progress through University. Given the relativity of self-perception metrics, we suggest that our results evince a āred queenā effect. In essence, as course expectations increase with each year, each studentās self-perceived autonomy relative to their ideal remains constant; we term this the āmoving goalpostā hypothesis. This article corroborates pedagogical literature suggesting that providing students with opportunities to act autonomously and develop confidence is key to developing graduates who have the independence that they need in order to be successful in the workplace
MICC: A tool for computing short distances in the curve complex
The complex of curves of a closed orientable surface of
genus is the simplicial complex having its vertices,
, are isotopy classes of essential curves in . Two
vertices co-bound an edge of the -skeleton, , if there
are disjoint representatives in . A metric is obtained on
by assigning unit length to each edge of
. Thus, the distance between two vertices, ,
corresponds to the length of a geodesic---a shortest edge-path between and
in . Recently, Birman, Margalit and the second author
introduced the concept of {\em initially efficient geodesics} in
and used them to give a new algorithm for computing the
distance between vertices. In this note we introduce the software package MICC
({\em Metric in the Curve Complex}), a partial implementation of the initially
efficient geodesic algorithm. We discuss the mathematics underlying MICC and
give applications. In particular, we give examples of distance four vertex
pairs, for and 3. Previously, there was only one known example, in genus
, due to John Hempel.Comment: 19 pages, 9 figures, Version 2 has updated figures and reference
Collective Interview on the History of Town Meetings
As illustrated in the introduction, the special issue ends with a ācollective interviewā to some distinguished
scholars that have given an important contribution to the study of New England Town Meetings. The collective interview has been realized by submitting three questions to our interviewees, who responded individually in written. The text of the answers has not been edited, if not minimally. However, the editors have broken up longer individual answers in shorter parts. These have been subsequently rearranged in an effort to provide, as much as possible, a fluid structure and a degree of interaction among the different perspectives provided by our interviewees on similar issues. The final version of this interview has been edited and approved by all interviewees
Genetics of pulmonary arterial hypertension: do the molecular findings have translational value?
Pulmonary arterial hypertension (PAH) is usually a devastating condition with a poor prognosis. Nearly 10 years ago, the underlying molecular basis of heritable PAH was elucidated with the identification of mutations in the gene encoding the bone morphogenetic protein type II receptor (BMPR-II). This discovery is now beginning to suggest novel approaches to therapy in heritable PAH. Moreover, recent studies provide evidence that dysfunction of the BMPR-II pathway is a feature of non-familial forms of PAH, broadening the scope for intervention in this pathway
Costs of colour change in fish: food intake and behavioural decisions
Many animals, particularly reptiles, amphibians, fish and cephalopods, have the ability to change their body colour, for functions including thermoregulation, signalling and predator avoidance. Many fish plastically darken their body colouration in response to dark visual backgrounds, and this functions to reduce predation risk. Here, we tested the hypotheses that colour change in fish (1) carries with it an energetic cost and (2) affects subsequent shoal and habitat choice decisions. We demonstrate that guppies (Poecilia reticulata) change colour in response to dark and light visual backgrounds, and that doing so carries an energetic cost in terms of food consumption. By increasing food intake, however, guppies are able to maintain growth rates and meet the energetic costs of changing colour. Following colour change, fish preferentially choose habitats and shoals that match their own body colouration, and maximise crypsis, thus avoiding the need for further colour change but also potentially paying an opportunity cost associated with restriction to particular habitats and social associates. Thus, colour change to match the background is complemented by behavioural strategies, which should act to maximise fitness in variable environments. Ā© 2013. Published by The Company of Biologists Ltd
Ethics as an act of listening
Over the past fifty years concerns regarding ethical and human rights abuses arising from biomedical research have led to the establishment of sophisticated processes for ethical oversight of research and to increasing regulation of many aspects of the research endeavour. Research using human tissue collections (tissue banking research) is no exception, with evermore stringent regulations emerging in response to concerns about consent, privacy and commercialisation. These measures are perfectly compatible with central bioethical concerns such as the need to ensure autonomy and the right to control oneās body and personal information, and the need to protect vulnerable research subjects from harm. So why, one might ask, are scientists so resentful of these regulations and so concerned about their potential adverse impact (e.g. Furness 2004)? Does this mean that the scientific community is dangerously insensitive to the publicās mistrust and desire for autonomy? Or are they more aware of public values? It is possible to theorise endlessly about such matters, but at some point it is necessary to carry out empirical research into public attitudes and values. While the āempirical turnā in bioethics has its limitations and is primarily descriptive, rather than normative (Sugarman 2004), as Chandros Hull et al remind us, if bioethics does not accurately reflect community values may impede science and misrepresent the needs of āvulnerableā populations
Functional interaction between BMPR-II and Tctex-1, a light chain of Dynein, is isoform-specific and disrupted by mutations underlying primary pulmonary hypertension
Diverse heterozygous mutations of bone morphogenetic receptor type II (BMPR-II) underlie the inherited form of the vascular disorder primary pulmonary hypertension (PPH). As yet, the molecular detail of how such defects contribute to the pathogenesis of PPH remains unclear. BMPR-II is a member of the transforming growth factor-beta cell signalling superfamily. Ligand binding induces cell surface receptor complex formation and activates a cascade of phosphorylation events of intracellular intermediaries termed Smads, which initiate transcriptional regulation. Some 30% of PPH-causing mutations localize to exon 12, which may be spliced out forming an isoform depleted of the unusually long BMPR-II cytoplasmic tail. To further elucidate the consequences of BMPR2 mutation, we sought to characterize aspects of the cytoplasmic domain function by seeking intracellular binding partners. We now report that Tctex-1, a light chain of the motor complex dynein, interacts with the cytoplasmic domain of BMPR-II and demonstrate that Tctex-1 is phosphorylated by BMPR-II, a function disrupted by PPH disease causing mutations within exon 12. Finally we show that BMPR-II and Tctex-1 co-localize to endothelium and smooth muscle within the media of pulmonary arterioles, key sites of vascular remodelling in PPH. Taken together, these data demonstrate a discrete function for the cytoplasmic domain of BMPR-II and justify further investigation of whether the interaction with and phosphorylation of Tctex-1 contributes to the pathogenesis of PPH
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