5,507 research outputs found
The development of path integration: combining estimations of distance and heading
Efficient daily navigation is underpinned by path integration, the mechanism by which we use self-movement information to update our position in space. This process is well-understood in adulthood, but there has been relatively little study of path integration in childhood, leading to an underrepresentation in accounts of navigational development. Previous research has shown that calculation of distance and heading both tend to be less accurate in children as they are in adults, although there have been no studies of the combined calculation of distance and heading that typifies naturalistic path integration. In the present study 5-year-olds and 7-year-olds took part in a triangle-completion task, where they were required to return to the startpoint of a multi-element path using only idiothetic information. Performance was compared to a sample of adult participants, who were found to be more accurate than children on measures of landing error, heading error, and distance error. 7-year-olds were significantly more accurate than 5-year-olds on measures of landing error and heading error, although the difference between groups was much smaller for distance error. All measures were reliably correlated with age, demonstrating a clear development of path integration abilities within the age range tested. Taken together, these data make a strong case for the inclusion of path integration within developmental models of spatial navigational processing
Arabidopsis thaliana VDAC2 involvement in salt stress response pathway
Soil salinity seriously affects plants distribution and yield, while salt stress induces SOS genes, and voltage-dependent anion channels (VDAC) and a mitochondrial porin, are induced too. In this paper, phenotypes of AtVDAC2 transgenic lines and wild type (RLD) were analyzed. It was found that AtVDAC2 over-expressing transgenic plants were more sensitive to NaCl, and produced more H2O2 in the NaCl treatment. Also, to find the inner reason, the salt overly sensitive gene 3 (SOS3) expression level was changed with the expression of AtVDAC2. So, it was conjectured that the signal of salt stress response was first sent to AtVDAC2, then AtVDAC2 expression improved, leading to the down-stream signals changes, such as accumulation of H2O2 and improved expression of SOS3. So, it was found that in the over-expression of transgenic lines with AtVDAC2 up-regulation, SOS3 expression increased significantly, and in the inhibited-expressing lines, it was vice versa. In summary, AtVDAC2 was involved in salt stress signaling pathway, and it regulated SOS3 gene expression.Key words: Arabidopsis thaliana, voltage-dependent anion channels (VDAC), salt stress, signaling pathway
Digitalisation for smarter cities: Moving from a static to a dynamic view
This paper presents a critical review of the literature on smart cities informed by a sociotechnical perspective that views ‘smart city development’ as a dynamic change process that extends to both the technological apparatus of the city and the social environment that produces, maintains and uses it. The conclusions from the review are summarised in six propositions. The propositions contest the mainstream discourse that often culminates in a utopian vision where data collection, processing, analysis and sharing provide solutions to all urban problems and provide direction for the future advancement of smart city research and practice. Using the propositions as guidelines to underpin a multidisciplinary approach, the paper sets out a relational perspective based on notions of boundary spanning, coordination and management that can shed light on previously overlooked aspects of smart city transitions.This work was supported by the Ove Arup Foundation and the Cambridge Centre for Smart Infrastructure and Construction – CSIC [grant reference: RG89525], Department of Engineering, University of Cambridge, Cambridge, United Kingdom
Conscious monitoring and control (reinvestment) in surgical performance under pressure.
Research on intraoperative stressors has focused on external factors without considering individual differences in the ability to cope with stress. One individual difference that is implicated in adverse effects of stress on performance is "reinvestment," the propensity for conscious monitoring and control of movements. The aim of this study was to examine the impact of reinvestment on laparoscopic performance under time pressure
The LKB1-salt-inducible kinase pathway functions as a key gluconeogenic suppressor in the liver
LKB1 is a master kinase that regulates metabolism and growth through adenosine monophosphate-activated protein kinase (AMPK) and 12 other closely related kinases. Liver-specific ablation of LKB1 causes increased glucose production in hepatocytes in vitro and hyperglycaemia in fasting mice in vivo. Here we report that the salt-inducible kinases (SIK1, 2 and 3), members of the AMPK-related kinase family, play a key role as gluconeogenic suppressors downstream of LKB1 in the liver. The selective SIK inhibitor HG-9-91-01 promotes dephosphorylation of transcriptional co-activators CRTC2/3 resulting in enhanced gluconeogenic gene expression and glucose production in hepatocytes, an effect that is abolished when an HG-9-91-01-insensitive mutant SIK is introduced or LKB1 is ablated. Although SIK2 was proposed as a key regulator of insulin-mediated suppression of gluconeogenesis, we provide genetic evidence that liver-specific ablation of SIK2 alone has no effect on gluconeogenesis and insulin does not modulate SIK2 phosphorylation or activity. Collectively, we demonstrate that the LKB1-SIK pathway functions as a key gluconeogenic gatekeeper in the liver
Cystoscopic removal of an intravesical gossypiboma mimicking a bladder mass: a case report
<p>Abstract</p> <p>Background</p> <p>Intravesical retained surgical sponges are very rare and only a few cases have been removed by minimally invasive techniques.</p> <p>Case presentation</p> <p>We report a case of an intravesical gossypiboma in a 71-year-old man from western Nepal, who presented with urinary retention and persistent lower urinary tract symptoms one year after open cystolithotomy. He was diagnosed with an intravesical mass using ultrasonography. The retained surgical sponge was found during cystoscopy and removed through endoscopy.</p> <p>Conclusion</p> <p>Intravesical gossypibomas are rare and can mimic a bladder mass. This is one of the few reported cases of cystoscopic removal.</p
Deriving a mutation index of carcinogenicity using protein structure and protein interfaces
With the advent of Next Generation Sequencing the identification of mutations in the genomes of healthy and diseased tissues has become commonplace. While much progress has been made to elucidate the aetiology of disease processes in cancer, the contributions to disease that many individual mutations make remain to be characterised and their downstream consequences on cancer phenotypes remain to be understood. Missense mutations commonly occur in cancers and their consequences remain challenging to predict. However, this knowledge is becoming more vital, for both assessing disease progression and for stratifying drug treatment regimes. Coupled with structural data, comprehensive genomic databases of mutations such as the 1000 Genomes project and COSMIC give an opportunity to investigate general principles of how cancer mutations disrupt proteins and their interactions at the molecular and network level. We describe a comprehensive comparison of cancer and neutral missense mutations; by combining features derived from structural and interface properties we have developed a carcinogenicity predictor, InCa (Index of Carcinogenicity). Upon comparison with other methods, we observe that InCa can predict mutations that might not be detected by other methods. We also discuss general limitations shared by all predictors that attempt to predict driver mutations and discuss how this could impact high-throughput predictions. A web interface to a server implementation is publicly available at http://inca.icr.ac.uk/
Axion-mediated dark matter and Higgs diphoton signal
We consider axion-mediated dark matter models motivated by Fermi gamma ray
line at 130 GeV, where anomaly interactions of an axion-like scalar mediate a
singlet Dirac fermion dark matter (DM) to electroweak gauge bosons. In these
models, extra vector-like leptons generate anomaly interactions for the axion
and can also couple to the SM Higgs boson to modify the Higgs-to-diphoton rate.
We can distinguish models by the branching fraction of the DM annihilation into
a photon pair, favoring the model with a triplet fermion. From the condition
that the lighter charged extra lepton must be heavier than dark matter for no
tree-level DM annihilations, we also show that the ratio of Higgs-to-diphoton
rate to the SM value is constrained by vacuum stability to 1.4(1.5) for the
cutoff scale of 10(1) TeV.Comment: 29 pages, 6 figures, references adde
Gene set of nuclear-encoded mitochondrial regulators is enriched for common inherited variation in obesity
There are hints of an altered mitochondrial function in obesity. Nuclear-encoded genes are relevant for mitochondrial function (3 gene sets of known relevant pathways: (1) 16 nuclear regulators of mitochondrial genes, (2) 91 genes for oxidative phosphorylation and (3) 966 nuclear-encoded mitochondrial genes). Gene set enrichment analysis (GSEA) showed no association with type 2 diabetes mellitus in these gene sets. Here we performed a GSEA for the same gene sets for obesity. Genome wide association study (GWAS) data from a case-control approach on 453 extremely obese children and adolescents and 435 lean adult controls were used for GSEA. For independent confirmation, we analyzed 705 obesity GWAS trios (extremely obese child and both biological parents) and a population-based GWAS sample (KORA F4, n = 1,743). A meta-analysis was performed on all three samples. In each sample, the distribution of significance levels between the respective gene set and those of all genes was compared using the leading-edge-fraction-comparison test (cut-offs between the 50(th) and 95(th) percentile of the set of all gene-wise corrected p-values) as implemented in the MAGENTA software. In the case-control sample, significant enrichment of associations with obesity was observed above the 50(th) percentile for the set of the 16 nuclear regulators of mitochondrial genes (p(GSEA,50) = 0.0103). This finding was not confirmed in the trios (p(GSEA,50) = 0.5991), but in KORA (p(GSEA,50) = 0.0398). The meta-analysis again indicated a trend for enrichment (p(MAGENTA,50) = 0.1052, p(MAGENTA,75) = 0.0251). The GSEA revealed that weak association signals for obesity might be enriched in the gene set of 16 nuclear regulators of mitochondrial genes
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