377 research outputs found
Exploring flow occurrence in elite golf
Research on flow (Csikszentmihalyi, 1975) has traditionally focused on reactive, externally-paced sports (e.g., tennis) without exploring those that are self-paced and stop-start in nature. This study investigated the occurrence of flow in a sample of thirteen elite golfers by conducting semi-structured interviews discussing: (i) their experiences of flow, (ii) factors that influenced flow occurrence, and (iii) the controllability of these experiences. Results shared similarity with existing research in terms of the majority of influencing factors reported, including motivation, preparation, focus, psychological state, environmental and situational conditions, and arousal, and that flow was reported to be at least potentially controllable. Golf-specific influences were also noted, including pre-shot routines, use of psychological interventions, standard of performance, and maintenance of physical state, suggesting that flow may have occurred differently for this sample. Findings are discussed and applied recommendations are made that may help golfers put relevant factors in place to increase the likelihood of experiencing flow
Hunger in Maine
Hunger and food insecurity is on the rise in Maine. Mainers are experiencing a food emergency made graver by the economic recession and rising health costs. The authors of this article discuss hunger in Maine, focusing on private efforts to alleviate it
Non cell autonomous upregulation of CDKN2 transcription linked to progression of chronic hepatitis C disease
Chronic hepatitis C virus infection (C-HC) is associated with higher mortality arising from hepatic and extrahepatic disease. This may be due to accelerated biological aging; however, studies in C-HC have thus far been based solely on telomere length as a biomarker of aging (BoA). In this study, we have evaluated CDKN2 locus transcripts as alternative BoAs in C-HC. Our results suggest that C-HC induces non-cell-autonomous senescence and accelerates biological aging. The CDKN2 locus may provide a link between C-HC and increased susceptibility to age-associated diseases and provides novel biomarkers for assessing its impact on aging processes in man
Para-cresol production by Clostridium difficile affects microbial diversity and membrane integrity of Gram-negative bacteria
Clostridium difficile is a Gram-positive spore-forming anaerobe and a major cause of antibiotic-associated diarrhoea. Disruption of the commensal microbiota, such as through treatment with broad-spectrum antibiotics, is a critical precursor for colonisation by C. difficile and subsequent disease. Furthermore, failure of the gut microbiota to recover colonisation resistance can result in recurrence of infection. An unusual characteristic of C. difficile among gut bacteria is its ability to produce the bacteriostatic compound para-cresol (p-cresol) through fermentation of tyrosine. Here, we demonstrate that the ability of C. difficile to produce p-cresol in vitro provides a competitive advantage over gut bacteria including Escherichia coli, Klebsiella oxytoca and Bacteroides thetaiotaomicron. Metabolic profiling of competitive co-cultures revealed that acetate, alanine, butyrate, isobutyrate, p-cresol and p-hydroxyphenylacetate were the main metabolites responsible for differentiating the parent strain C. difficile (630Δerm) from a defined mutant deficient in p-cresol production. Moreover, we show that the p-cresol mutant displays a fitness defect in a mouse relapse model of C. difficile infection (CDI). Analysis of the microbiome from this mouse model of CDI demonstrates that colonisation by the p-cresol mutant results in a distinctly altered intestinal microbiota, and metabolic profile, with a greater representation of Gammaproteobacteria, including the Pseudomonales and Enterobacteriales. We demonstrate that Gammaproteobacteria are susceptible to exogenous p-cresol in vitro and that there is a clear divide between bacterial Phyla and their susceptibility to p-cresol. In general, Gram-negative species were relatively sensitive to p-cresol, whereas Gram-positive species were more tolerant. This study demonstrates that production of p-cresol by C. difficile has an effect on the viability of intestinal bacteria as well as the major metabolites produced in vitro. These observations are upheld in a mouse model of CDI, in which p-cresol production affects the biodiversity of gut microbiota and faecal metabolite profiles, suggesting that p-cresol production contributes to C. difficile survival and pathogenesis.Peer reviewedFinal Published versio
NKG2D function protects the host from tumor initiation
The activation NKG2D receptor has been shown to play an important role in the control of experimental tumor growth and metastases expressing ligands for NKG2D; however, a function for this recognition pathway in host protection from de novo tumorigenesis has never been demonstrated. We show that neutralization of NKG2D enhances the sensitivity of wild-type (WT) C57BL/6 and BALB/c mice to methylcholanthrene (MCA)-induced fibrosarcoma. The importance of the NKG2D pathway was additionally illustrated in mice deficient for either IFN-γ or tumor necrosis factor–related apoptosis-inducing ligand, whereas mice depleted of natural killer cells, T cells, or deficient for perforin did not display any detectable NKG2D phenotype. Furthermore, IL-12 therapy preventing MCA-induced sarcoma formation was also largely dependent on the NKG2D pathway. Although NKG2D ligand expression was variable or absent on sarcomas emerging in WT mice, sarcomas derived from perforin-deficient mice were Rae-1+ and immunogenic when transferred into WT syngeneic mice. These findings suggest an important early role for the NKG2D in controlling and shaping tumor formation
Psychological States Underlying Excellent Performance in Sport: Toward an Integrated Model of Flow and Clutch States
This study investigated the psychological states underlying excellent performance in 26 athletes (Mage = 29 years, SD = 7.7) across a range of sports (team, net/wall, sprint, endurance, adventure) and standards (world class to recreational). Participants were primarily interviewed on average 4 days after excellent performances. The data were analyzed thematically. Distinct states of flow and clutch were reported, each of which occurred through separate contexts and processes, while athletes also transitioned between states during performance. These findings extend current knowledge of the psychology of excellent performance and are discussed in terms of implications for future research and applied practice
Expert Opinions: Current Pricing and Revenue Management Practice Across U.S. Industries
On May 18, 2006, the second annual Revenue Management and Price Optimization conference
was held at the Georgia Institute of Technology. The theme of the conference was on how the Internet is changing traditional revenue management and pricing practices. The conference brought together experts and thought leaders from more than 30 companies; spanning airlines, hotels, car rentals, cruise lines, apartment rentals, aircraft manufacturing, retailing, distribution, e-mail marketing, on-line travel, logistics, sports, performing arts, software providers, and others. This paper summarizes the key discussions from this conference and synthesizes experts’ perspectives on near-term opportunities and challenges facing their industries
The pH dependency of the boron isotopic composition of diatom opal (Thalassiosira weissflogii)
The high-latitude oceans are key areas of carbon and heat exchange between the atmosphere and the ocean. As such, they are a focus of both modern oceanographic and palaeoclimate research. However, most palaeoclimate proxies that could provide a long-term perspective are based on calcareous organisms, such as foraminifera, that are scarce or entirely absent in deep-sea sediments south of 50∘ S in the Southern Ocean and north of 40∘ N in the North Pacific. As a result, proxies need to be developed for the opal-based organisms (e.g. diatoms) found at these high latitudes, which dominate the biogenic sediments recovered from these regions. Here we present a method for the analysis of the boron (B) content and isotopic composition (δ11B) of diatom opal. We apply it for the first time to evaluate the relationship between seawater pH, δ11B and B concentration ([B]) in the frustules of the diatom Thalassiosira weissflogii, cultured across a range of carbon dioxide partial pressure (pCO2) and pH values. In agreement with existing data, we find that the [B] of the cultured diatom frustules increases with increasing pH (Mejía et al., 2013). δ11B shows a relatively well defined negative trend with increasing pH, completely distinct from any other biomineral previously measured. This relationship not only has implications for the magnitude of the isotopic fractionation that occurs during boron incorporation into opal, but also allows us to explore the potential of the boron-based proxies for palaeo-pH and palaeo-CO2 reconstruction in high-latitude marine sediments that have, up until now, eluded study due to the lack of suitable carbonate material
Hierarchical variation in phenotypic flexibility across timescales and associated survival selection shape the dynamics of partial seasonal migration
We thank everyone from UK Centre for Ecology & Hydrology and University of Aberdeen (UoA) who contributed to data collection, particularly Hannah Grist and Jenny Sturgeon; NatureScot for access to the Isle of May National Nature Reserve; Scottish Ornithologists' Club (SOC) for their support; and all volunteer observers, particularly Raymond Duncan and Moray Souter. This work was funded by Natural Environment Research Council (NERC; award NE/R000859/1 and award NE/R016429/1 as part of the UK-SCaPE programme delivering National Capability), Norwegian Research Council (SFF-III grant 223257), NTNU, UK Royal Society, Marine Alliance for Science and Technology for Scotland (MASTS), SOC and UoA.Peer reviewedPostprin
Recommended from our members
The impact of sequencing depth on the inferred taxonomic composition and AMR gene content of metagenomic samples
Shotgun metagenomics is increasingly used to characterise microbial communities, particularly for the investigation of antimicrobial resistance (AMR) in different animal and environmental contexts. There are many different approaches for inferring the taxonomic composition and AMR gene content of complex community samples from shotgun metagenomic data, but there has been little work establishing the optimum sequencing depth, data processing and analysis methods for these samples. In this study we used shotgun metagenomics and sequencing of cultured isolates from the same samples to address these issues. We sampled three potential environmental AMR gene reservoirs (pig caeca, river sediment, effluent) and sequenced samples with shotgun metagenomics at high depth (~ 200 million reads per sample). Alongside this, we cultured single-colony isolates of Enterobacteriaceae from the same samples and used hybrid sequencing (short- and long-reads) to create high- quality assemblies for comparison to the metagenomic data. To automate data processing, we developed an open- source software pipeline, ‘ResPipe’
- …