337 research outputs found

    Beneath the lens: Exploring the impacts of underwater photographers in marine-based tourism

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    As scuba diving proliferates in popularity as a nature-based recreational activity, the associated benefits and impacts are correspondingly emerging. Previous studies showed that underwater photographers are potentially the more impactful group of scuba divers. To further explore the impacts and behaviour of underwater photographers, this study attempted to predict their impacts through three photography-related variables, including species of interest, photography habit, and photography commitment through a case study in Hong Kong. A scuba diver survey was performed in summer 2021 to assess the impacts of divers, a follow-up questionnaire survey was delivered, and a total of 106 samples were collected. Findings showed that underwater photographers caused more negative impacts than ordinary scuba divers. Among underwater photographers, individuals more interested in conspicuous and actively moving species have more frequent contact with marine organisms. In contrast, those more interested in cryptic and sedentary species were more likely to cause intentional contact. Underwater photographers with greater commitment also showed more frequent and more intentional connections. Implications were drawn regarding underwater photographers' behaviors, and relevant suggestions were recommended to address the potential concerns

    Hydromorphological, hydraulic and ecological effects of restored wood: findings and reflections from an academic partnership approach

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    This is the peer reviewed version of the following article: Pinto, C. , Ing, R. , Browning, B. , Delboni, V. , Wilson, H. , Martyn, D. and Harvey, G. L. (2019), Hydromorphological, hydraulic and ecological effects of restored wood: findings and reflections from an academic partnership approach. Water and Environment Journal. doi:10.1111/wej.12457, which has been published in final form at https://doi.org/10.1111/wej.12457. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions© 2019 CIWEM Large wood (re)introduction can deliver multiple benefits in river restoration, but there is a dearth of the detailed and longer-term post-project monitoring and evaluation required for improving best practice. We present findings from an academic partnership approach to post-project evaluation, based on successive MSc research projects on restored large wood in the Loddon catchment, UK. Field and modelling data reveal: (i) key differences in large wood features between restored and natural reaches; (ii) increased hydraulic retention and changes to mesohabitats associated with large wood; (iii) differences in macroinvertebrate community composition around large wood but a lack of site-level effects; (iv) interactions between macrophytes and large wood that may be specific to restored reaches; (v) a need for further field and modelling studies to inform the accurate representation of large wood in hydraulic models. Some key challenges in partnership working are identified to aid planning and effectiveness of future collaborations

    Possible association between a genetic polymorphism at 8q24 and risk of upper gastrointestinal cancer

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    Over recent years, genome wide association studies (GWAS) have contributed to our understanding of genetic susceptibility to sporadic cancer. In this study, we assessed the association between upper gastrointestinal cancer risk and four GWAS-identified single nucleotide polymorphisms (SNPs), previously implicated in prostate and colorectal cancer susceptibility. Genotyping for each SNP was performed in two, independent, Caucasian, population-based case-control studies. The first study comprised 290 gastric cancer cases and 374 controls. The second study included 185 non-cardia gastric cancers, 123 cardia cancers, 158 oesophageal cancers, and 209 controls. Odds ratios were computed from logistic models and adjusted for potential confounding variables. An inverse association was observed between the SNP rs1447295, located at 8q24, and gastric cancer risk in the first study population (odds ratio [OR] = 0.63; 95% Confidence Interval [CI], 0.41–0.97). A positive association was observed for the same SNP and oesophageal squamous cell carcinoma in the second study population (OR = 7.43; 95% CI, 1.37–49.98). No significant associations were detected in either study for the three remaining SNPs (rs6983297, rs10505477 and rs719725). Our data represent novel findings on heritable susceptibility to gastric and oesophageal cancer and warrant validation in additional populations

    Knowledge Sharing Idiosyncrasies of University Students in Ghana

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    Part 6: Decision Making and Knowledge ManagementInternational audienceThis study explored the factors affecting knowledge sharing behaviour of students in a higher institution of learning. Using a model derived from the Social Cognitive Theory and the Theory of Reason Action, six hypotheses were tested from a cross-sectional data collected from 371 undergraduate students on a 4-year degree programme in the University of Ghana. Five out of the six hypotheses were supported. The results showed that the knowledge sharing behaviour (KSB) of the students was significantly related to five of the human and environmental factors (F=639.9, df=5, 290, p<0.05) with a co-efficient of variation of R2=0.917 (91.7%). The knowledge sharing behavior of the students was, however, not significantly dependent on their personal characteristics. The study makes a case for increased attention in understanding the human and environmental factors of knowledge sharing since knowledge sharing is largely a people activity shaped by culture

    Measurement of the View the tt production cross-section using eμ events with b-tagged jets in pp collisions at √s = 13 TeV with the ATLAS detector

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    This paper describes a measurement of the inclusive top quark pair production cross-section (σtt¯) with a data sample of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of √s = 13 TeV, collected in 2015 by the ATLAS detector at the LHC. This measurement uses events with an opposite-charge electron–muon pair in the final state. Jets containing b-quarks are tagged using an algorithm based on track impact parameters and reconstructed secondary vertices. The numbers of events with exactly one and exactly two b-tagged jets are counted and used to determine simultaneously σtt¯ and the efficiency to reconstruct and b-tag a jet from a top quark decay, thereby minimising the associated systematic uncertainties. The cross-section is measured to be: σtt¯ = 818 ± 8 (stat) ± 27 (syst) ± 19 (lumi) ± 12 (beam) pb, where the four uncertainties arise from data statistics, experimental and theoretical systematic effects, the integrated luminosity and the LHC beam energy, giving a total relative uncertainty of 4.4%. The result is consistent with theoretical QCD calculations at next-to-next-to-leading order. A fiducial measurement corresponding to the experimental acceptance of the leptons is also presented

    Muon reconstruction performance of the ATLAS detector in proton–proton collision data at √s = 13 TeV

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    This article documents the performance of the ATLAS muon identification and reconstruction using the LHC dataset recorded at √s = 13 TeV in 2015. Using a large sample of J/ψ→μμ and Z→μμ decays from 3.2 fb−1 of pp collision data, measurements of the reconstruction efficiency, as well as of the momentum scale and resolution, are presented and compared to Monte Carlo simulations. The reconstruction efficiency is measured to be close to 99% over most of the covered phase space (|η| 2.2, the pT resolution for muons from Z→μμ decays is 2.9 % while the precision of the momentum scale for low-pT muons from J/ψ→μμ decays is about 0.2%

    Measurement of the dependence of transverse energy production at large pseudorapidity on the hard-scattering kinematics of proton-proton collisions at √s=2.76 TeV with ATLAS

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    The relationship between jet production in the central region and the underlying-event activity in a pseudorapidity-separated region is studied in 4.0 pb-1 of s=2.76 TeV pp collision data recorded with the ATLAS detector at the LHC. The underlying event is characterised through measurements of the average value of the sum of the transverse energy at large pseudorapidity downstream of one of the protons, which are reported here as a function of hard-scattering kinematic variables. The hard scattering is characterised by the average transverse momentum and pseudorapidity of the two highest transverse momentum jets in the event. The dijet kinematics are used to estimate, on an event-by-event basis, the scaled longitudinal momenta of the hard-scattered partons in the target and projectile beam-protons moving toward and away from the region measuring transverse energy, respectively. Transverse energy production at large pseudorapidity is observed to decrease with a linear dependence on the longitudinal momentum fraction in the target proton and to depend only weakly on that in the projectile proton. The results are compared to the predictions of various Monte Carlo event generators, which qualitatively reproduce the trends observed in data but generally underpredict the overall level of transverse energy at forward pseudorapidity

    Search for strong gravity in multijet final states produced in pp collisions at √s=13 TeV using the ATLAS detector at the LHC

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    A search is conducted for new physics in multijet final states using 3.6 inverse femtobarns of data from proton-proton collisions at √s = 13TeV taken at the CERN Large Hadron Collider with the ATLAS detector. Events are selected containing at least three jets with scalar sum of jet transverse momenta (HT) greater than 1TeV. No excess is seen at large HT and limits are presented on new physics: models which produce final states containing at least three jets and having cross sections larger than 1.6 fb with HT > 5.8 TeV are excluded. Limits are also given in terms of new physics models of strong gravity that hypothesize additional space-time dimensions

    Search for TeV-scale gravity signatures in high-mass final states with leptons and jets with the ATLAS detector at sqrt [ s ] = 13TeV

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    A search for physics beyond the Standard Model, in final states with at least one high transverse momentum charged lepton (electron or muon) and two additional high transverse momentum leptons or jets, is performed using 3.2 fb−1 of proton–proton collision data recorded by the ATLAS detector at the Large Hadron Collider in 2015 at √s = 13 TeV. The upper end of the distribution of the scalar sum of the transverse momenta of leptons and jets is sensitive to the production of high-mass objects. No excess of events beyond Standard Model predictions is observed. Exclusion limits are set for models of microscopic black holes with two to six extra dimensions

    Measurement of the correlation between flow harmonics of different order in lead-lead collisions at √sNN = 2.76 TeV with the ATLAS detector

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    Correlations between the elliptic or triangular flow coefficients vm (m=2 or 3) and other flow harmonics vn (n=2 to 5) are measured using √sNN=2.76 TeV Pb+Pb collision data collected in 2010 by the ATLAS experiment at the LHC, corresponding to an integrated luminosity of 7 μb−1. The vm−vn correlations are measured in midrapidity as a function of centrality, and, for events within the same centrality interval, as a function of event ellipticity or triangularity defined in a forward rapidity region. For events within the same centrality interval, v3 is found to be anticorrelated with v2 and this anticorrelation is consistent with similar anticorrelations between the corresponding eccentricities, ε2 and ε3. However, it is observed that v4 increases strongly with v2, and v5 increases strongly with both v2 and v3. The trend and strength of the vm−vn correlations for n=4 and 5 are found to disagree with εm−εn correlations predicted by initial-geometry models. Instead, these correlations are found to be consistent with the combined effects of a linear contribution to vn and a nonlinear term that is a function of v22 or of v2v3, as predicted by hydrodynamic models. A simple two-component fit is used to separate these two contributions. The extracted linear and nonlinear contributions to v4 and v5 are found to be consistent with previously measured event-plane correlations
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