1,041 research outputs found
The effects of social conformity on Gouldian finch personality
Consistent individual differences in behaviour observed within a population are termed ‘personality’. Studies of personality typically test subjects in isolation, ignoring the potential effects of the social environment, which might restrict the expression of individual behaviour via conformity, or enhance it by facilitation. The Gouldian finch, Erythrura gouldiae, exhibits polymorphism in head colour (red or black) which is related to different personalities: black-headed birds are bolder and less aggressive than red-headed birds. As such, this species provides a unique opportunity to investigate the effects of the presence of a social partner on the expression of individual behaviour. Using two behavioural tests that reflect individual ‘boldness’, exploration of a novel object and time taken to return to feeding following a predator threat, we show that Gouldian finches adjusted their behaviour according to the personality of their partners: where a bird's partner was bolder, it became bolder; where a bird's partner was shyer, it became shyer. This social conformity effect was reduced, however, for black-headed birds paired with red-headed partners in the novel object test; in keeping with previous research findings, bolder individuals were less plastic in their responses. Since variation in personality can promote group cohesion and improve the functioning of social groups in a variety of contexts, we hypothesize that head colour could act as a cue, facilitating preferential associations with those of similar or dissimilar personalities in large mobile flocks of Gouldian finches
The covid-19 learning crisis as a challenge and an opportunity for schools: An evidence review and conceptual synthesis of research-based tools for sustainable change
This paper advances our understanding of how schools can become change agents capable of transforming local practice to address the challenges arising from the Covid-19 pandemic. It presents a novel application of cultural-historical activity theory to reinterpret evidence on widespread learning loss and increasing educational inequities resulting from the pandemic, and to identify scalable transformative learning opportunities through reframing the crisis as a double stimulation. By reviewing evidence of the emerging educational landscape, we first develop a picture of the new ‘problem space’ upon which schools must act. We develop a problem space map to serve as the first stimulus to articulate local challenges. Integrating this problem space with research on professional change, we identify conceptual tools to capture learning gaps and implement pedagogic interventions at scale, in order to enhance schools’ agency in directly addressing the crisis. These tools can act as the second stimulus, enabling educators to address local challenges. We conclude by discussing the Covid-19 educational crisis as a unique stimulus for professional learning and outline the potential for durable shifts in educational thinking and practice beyond the pandemic. We argue that this unprecedented historic disruption can be harnessed as a transformative professional learning opportunity. In particular, we consider how research on professional change offers local, scalable interventions and tools that can support educators in preventing the new insights from ‘slipping away’ post-pandemic. Utilising the notions of boundaries and tool-mediated professional change, we examine the ways in which this disruption generates opportunities to envision alternative futures for equitable learning in school.Author 1:
The epiSTEMe project [grant number RES-179-25-0003, PI Prof. K. Ruthven]
The TEACh project [ES/M005445/1, PI Prof. P. Rose]
ESRC Impact Acceleration Grant, University of Cambridge [PI Dr. R. Hofmann]
Cambridge University Health Partners
Commonwealth Education Trust (PI. Prof. S. Hennessy)
Authors 2-8:
(2) Faculty of Education, University of Cambridge, PhD scholarship
(3) Economic and Social Research Council PhD scholarship [ES/P000738/1]
(4) Agencia Nacional de Investigación y Desarrollo (ANID), Cambridge Trust, PhD scholarship
(5) Economic and Social Research Council [ES/P000738/1] and MRC Epidemiology Unit PhD scholarship
(6) Yayasan Khazanah, Cambridge Trust, PhD scholarship
(7) Guy’s and St Thomas’ Charity, UK [TCF180902] PhD scholarship
(8) The LEGO Foundatio
Chemo- and Thermosensory Responsiveness of Grueneberg Ganglion Neurons Relies on Cyclic Guanosine Monophosphate Signaling Elements
Neurons of the Grueneberg ganglion (GG) in the anterior nasal region of mouse pups respond to cool temperatures and to a small set of odorants. While the thermosensory reactivity appears to be mediated by elements of a cyclic guanosine monophosphate (cGMP) cascade, the molecular mechanisms underlying the odor-induced responses are unclear. Since odor-responsive GG cells are endowed with elements of a cGMP pathway, specifically the transmembrane guanylyl cyclase subtype GC-G and the cyclic nucleotide-gated ion channel CNGA3, the possibility was explored whether these cGMP signaling elements may also be involved in chemosensory GG responses. Experiments with transgenic mice deficient for GC-G or CNGA3 revealed that GG responsiveness to given odorants was significantly diminished in these knockout animals. These findings suggest that a cGMP cascade may be important for both olfactory and thermosensory signaling in the GG. However, in contrast to the thermosensory reactivity, which did not decline over time, the chemosensory response underwent adaptation upon extended stimulation, suggesting that the two transduction processes only partially overlap. Copyright (C) 2011 S. Karger AG, Base
Functional polymorphisms in the promoter regions of MMP2 and MMP3 are not associated with melanoma progression
<p>Abstract</p> <p>Background</p> <p>The matrix metalloproteinases (MMPs) are enzymes that cleave various components of the extracellular matrix (ECM) and basement membranes. MMPs are expressed in melanocytes and their overexpression has been linked to tumor development, progression and metastasis. At the genetic level, the following functional promoter polymorphisms are known to modify the gene transcription: -1306 C/T and -735 C/T in the MMP2 gene, and -1171 5A/6A in the MMP3 gene. Functional polymorphisms in MMP genes' promoter regions may modulate the risk for melanoma progression.</p> <p>Methods</p> <p>We evaluated MMP2 and MMP3 germline polymorphisms in a group of 1002 melanoma patients using PCR-based methods, including fragment size analysis and melting temperature profiles. Two-sided Chi-Square, Cochran-Armitage tests for trend, Fisher's exact tests, and Kendall's Tau tests were performed to evaluate the associations between genotype and various clinical and epidemiologic factors. Multivariate analyses were conducted using logistic regression, adjusting for known melanoma confounders such as age, sex, phenotypic index, moles, freckles, and race. Survival estimates were computed using the Kaplan-Meier method and differences in survival were assessed using the log rank test.</p> <p>Results</p> <p>All genotypes were in Hardy-Weinberg equilibrium. After adjustment for age, sex and phenotypic characteristics of melanoma risk, no significant associations were identified with the clinical, pathological, and epidemiological variables studied. The melting profile for MMP2 -735 C/T identified a new change in one sample. A new PCR-amplification followed by direct sequencing confirmed a heterozygote G to A substitution at position -729.</p> <p>Conclusion</p> <p>This study does not provide strong evidence for further investigation into the role of the MMP2 and MMP3 variants in melanoma progression.</p
Surface Electron-Hole Rich Species Active in the Electrocatalytic Water Oxidation
Iridium and ruthenium and their oxides/hydroxides are the best candidates for the oxygen evolution reaction under harsh acidic conditions owing to the low overpotentials observed for Ru- and Ir-based anodes and the high corrosion resistance of Ir-oxides. Herein, by means of cutting edge operando surface and bulk sensitive X-ray spectroscopy techniques, specifically designed electrode nanofabrication and ab initio DFT calculations, we were able to reveal the electronic structure of the active IrOx centers (i.e., oxidation state) during electrocatalytic oxidation of water in the surface and bulk of high-performance Ir-based catalysts. We found the oxygen evolution reaction is controlled by the formation of empty Ir 5d states in the surface ascribed to the formation of formally IrV species leading to the appearance of electron-deficient oxygen species bound to single iridium atoms (μ1-O and μ1-OH) that are responsible for water activation and oxidation. Oxygen bound to three iridium centers (μ3-O) remains the dominant species in the bulk but do not participate directly in the electrocatalytic reaction, suggesting bulk oxidation is limited. In addition a high coverage of a μ1-OO (peroxo) species during the OER is excluded. Moreover, we provide the first photoelectron spectroscopic evidence in bulk electrolyte that the higher surface-to-bulk ratio in thinner electrodes enhances the material usage involving the precipitation of a significant part of the electrode surface and near-surface active species
Genotoxic agents promote the nuclear accumulation of annexin A2: role of annexin A2 in mitigating DNA damage
Annexin A2 is an abundant cellular protein that is mainly localized in the cytoplasm and plasma membrane, however a small population has been found in the nucleus, suggesting a nuclear function for the protein. Annexin A2 possesses a nuclear export sequence (NES) and inhibition of the NES is sufficient to cause nuclear accumulation. Here we show that annexin A2 accumulates in the nucleus in response to genotoxic agents including gamma-radiation, UV radiation, etoposide and chromium VI and that this event is mediated by the nuclear export sequence of annexin A2. Nuclear accumulation of annexin A2 is blocked by the antioxidant agent N-acetyl cysteine (NAC) and stimulated by hydrogen peroxide (H2O2), suggesting that this is a reactive oxygen species dependent event. In response to genotoxic agents, cells depleted of annexin A2 show enhanced phospho-histone H2AX and p53 levels, increased numbers of p53-binding protein 1 nuclear foci and increased levels of nuclear 8-oxo-2'-deoxyguanine, suggesting that annexin A2 plays a role in protecting DNA from damage. This is the first report showing the nuclear translocation of annexin A2 in response to genotoxic agents and its role in mitigating DNA damage.Natural Sciences and Engineering Research Council of Canada (NSERC); European Union [PCOFUND-GA-2009-246542]; Foundation for Science and Technology of Portugal; Beatrice Hunter Cancer Research Institute; Terry Fox Foundationinfo:eu-repo/semantics/publishedVersio
Identification and characterization of a novel non-structural protein of bluetongue virus
Bluetongue virus (BTV) is the causative agent of a major disease of livestock (bluetongue). For over two decades, it has been widely accepted that the 10 segments of the dsRNA genome of BTV encode for 7 structural and 3 non-structural proteins. The non-structural proteins (NS1, NS2, NS3/NS3a) play different key roles during the viral replication cycle. In this study we show that BTV expresses a fourth non-structural protein (that we designated NS4) encoded by an open reading frame in segment 9 overlapping the open reading frame encoding VP6. NS4 is 77–79 amino acid residues in length and highly conserved among several BTV serotypes/strains. NS4 was expressed early post-infection and localized in the nucleoli of BTV infected cells. By reverse genetics, we showed that NS4 is dispensable for BTV replication in vitro, both in mammalian and insect cells, and does not affect viral virulence in murine models of bluetongue infection. Interestingly, NS4 conferred a replication advantage to BTV-8, but not to BTV-1, in cells in an interferon (IFN)-induced antiviral state. However, the BTV-1 NS4 conferred a replication advantage both to a BTV-8 reassortant containing the entire segment 9 of BTV-1 and to a BTV-8 mutant with the NS4 identical to the homologous BTV-1 protein. Collectively, this study suggests that NS4 plays an important role in virus-host interaction and is one of the mechanisms played, at least by BTV-8, to counteract the antiviral response of the host. In addition, the distinct nucleolar localization of NS4, being expressed by a virus that replicates exclusively in the cytoplasm, offers new avenues to investigate the multiple roles played by the nucleolus in the biology of the cell
TNF-α increases human melanoma cell invasion and migration in vitro: the role of proteolytic enzymes
Inflammatory mediators have been reported to promote malignant cell growth, invasion and metastatic potential. More specifically,
we have recently reported that tumour necrosis factor alpha (TNF-a) increases melanoma cell attachment to extracellular matrix
(ECM) substrates and invasion through fibronectin. In this study, we extend these investigations asking specifically whether the TNF-a
effect on cell invasion and migration involves activation of proteolytic enzymes. We examined the effect of TNF-a on melanoma
expression/activation of type IV gelatinases matrix metalloproteinases 2 and 9 (MMPs -2 and -9) and general proteolytic enzymes.
Stimulation with TNF-a significantly increased both melanoma cell migration at 24 h ( þ 21%) and invasion through fibronectin
( þ 35%) but did not upregulate/activate the expression of latent MMP-2 constitutively produced by these cells and did not
upregulate their general protease activity. However, the increased cell migration and invasion through fibronectin observed following
stimulation with TNF-a were inhibited by the general protease inhibitor a2 macroglobulin. These findings suggest that the
promigratory and proinvasive effect of TNF-a on this melanoma cell line may be mediated to some extent by induction of localised
cell membrane-bound degradative enzyme activity, which is not readily detected in biochemical assays
hMMS2 serves a redundant role in human PCNA polyubiquitination
<p>Abstract</p> <p>Background</p> <p>In yeast, DNA damage leads to the mono and polyubiquitination of the sliding clamp PCNA. Monoubiquitination of PCNA is controlled by RAD18 (E3 ligase) and RAD6 (E2 conjugating enzyme), while the extension of the monoubiquitinated PCNA into a polyubiquitinated substrate is governed by RAD5, and the heterodimer of UBC13/MMS2. Each modification directs a different branch of the DNA damage tolerance pathway (DDT). While PCNA monoubiquitination leads to error-prone bypass via TLS, biochemical studies have identified MMS2 along with its heteromeric partner UBC13 to govern the error-free repair of DNA lesions by catalyzing the formation of lysine 63-linked polyubiquitin chains (K63-polyUb). Recently, it was shown that PCNA polyubiquitination is conserved in human cells and that this modification is dependent on RAD18, UBC13 and SHPRH. However, the role of hMMS2 in this process was not specifically addressed.</p> <p>Results</p> <p>In this report we show that mammalian cells in which MMS2 was reduced by siRNA-mediated knockdown maintains PCNA polyubiquitination while a knockdown of RAD18 or UBC13 abrogates PCNA ubiquitination. Moreover, the additional knockdown of a UEV1A (MMS2 homolog) does not deplete PCNA polyubiquitination. Finally, mouse embryonic stem cells null for MMS2 with or without the additional depletion of mUEV1A continue to polyubiquitinated PCNA with normal kinetics.</p> <p>Conclusion</p> <p>Our results point to a high level of redundancy in the DDT pathway and suggest the existence of another hMMS2 variant (hMMSv) or complex that can compensate for its loss.</p
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Protocol for a feasibility study of a self help cognitive behavioural therapy resource for the reduction of dental anxiety in young people
Background
Childhood dental anxiety is very common, with 10–20 % of children and young people reporting high levels of dental anxiety. It is distressing and has a negative impact on the quality of life of young people and their parents as well as being associated with poor oral health. Affected individuals may develop a lifelong reliance on general anaesthetic or sedation for necessary dental treatment thus requiring the support of specialist dental services. Children and young people with dental anxiety therefore require additional clinical time and can be costly to treat in the long term. The reduction of dental anxiety through the use of effective psychological techniques is, therefore, of high importance. However, there is a lack of high-quality research investigating the impact of cognitive behavioural therapy (CBT) approaches when applied to young people’s dental anxiety.
Methods/design
The first part of the study will develop a profile of dentally anxious young people using a prospective questionnaire sent to a consecutive sample of 100 young people referred to the Paediatric Dentistry Department, Charles Clifford Dental Hospital, in Sheffield. The second part will involve interviewing a purposive sample of 15–20 dental team members on their perceptions of a CBT self-help resource for dental anxiety, their opinions on whether they might use such a resource with patients, and their willingness to recruit participants to a future randomised controlled trial (RCT) to evaluate the resource. The third part of the study will investigate the most appropriate outcome measures to include in a trial, the acceptability of the resource, and retention and completion rates of treatment with a sample of 60 dentally anxious young people using the CBT resource.
Discussion
This study will provide information on the profile of dentally anxious young people who could potentially be helped by a guided self-help CBT resource. It will gain the perceptions of dental care team members of guided self-help CBT for dental anxiety in young people and their willingness to recruit participants to a trial. Acceptability of the resource to participants and retention and completion rates will also be investigated to inform a future RCT
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