608 research outputs found
Interactive effects of temperature and salinity on otolith chemistry: challenges for determining environmental histories of fish
Copyright © 2002 NRC CanadaThe concentrations of elements and isotopes in fish otoliths may provide a method of reconstructing movements of fish by differentiating between water bodies of different temperatures and salinities. However, before otoliths can be used to reconstruct environmental histories of fish, it is necessary to assess the effects of seawater temperature and salinity on otolith microchemistry. Using controlled laboratory experiments, juvenile black bream, Acanthopagrus butcheri (family Sparidae), were reared for 50 days in aquaria of varying temperatures and salinities using three experimental designs: temperature x salinity, temperature only, and salinity only. Temperature and salinity interacted to significantly affect the elemental concentration ratios of Sr:Ca and Ba:Ca and the concentrations of isotopes 7delta;[sup13] C and δ[sup18] O in otoliths. The single-factor experiments showed that temperature significantly affected the concentration ratios of Sr:Ca and Ba:Ca and the concentrations of δ[sup13]C and δ[sup18]O in otoliths, whereas salinity alone did not affect the concen-tration ratios of any elements but did affect both isotopes. The concentration ratios of Mg:Ca and Mn:Ca varied considerably among fish within the same treatment level and showed little or no effects due to temperature and (or) salinity. The significant interactive effects of temperature and salinity on otolith microchemistry highlight the need for a multifactorial approach to testing hypotheses regarding the environmental histories of fish.Travis S. Elsdon and Bronwyn M. Gillander
Recommended from our members
'Feel the Feeling': Psychological practitioners' experience of acceptance and commitment therapy well-being training in the workplace.
This empirical study investigates psychological practitioners' experience of worksite training in acceptance and commitment therapy using an interpretative phenomenological analysis methodology. Semi-structured interviews were conducted with eight participants, and three themes emerged from the interpretative phenomenological analysis data analysis: influence of previous experiences, self and others and impact and application. The significance of the experiential nature of the acceptance and commitment therapy training is explored as well as the dual aspects of developing participants' self-care while also considering their own clinical practice. Consistencies and inconsistencies across acceptance and commitment therapy processes are considered as well as clinical implications, study limitations and future research suggestions
Behind the masks:A cross-sectional study on intolerance of uncertainty, perceived vulnerability to disease and psychological flexibility in relation to anxiety and wellbeing during the COVID-19 pandemic
Early findings suggest the COVID-19 pandemic and related containment measures negatively impact mental wellbeing. This study compared the contribution and relations of three factors to anxiety and wellbeing during the pandemic in June 2020. These factors were: i) Contextual factors (e.g. exposure to COVID-19, being a keyworker, feeling lonely); ii) Cognitive appraisals: perceived vulnerability to disease (PVD) and intolerance of uncertainty (IU); and iii) psychological flexibility (PF). 603 participants aged 18 or older completed an online survey of self-report measures. Hierarchical regression analyses demonstrated PVD, IU and PF predicted state anxiety, and IU and PF predicted mental wellbeing. Some, but not all of the contextual factors also predicted state anxiety and wellbeing. The findings support cognitive appraisal theories and the PF model, lending support to an acceptance and commitment therapy (ACT) approach to public health during pandemics
Optimizing antibiotic therapy-the Aberdeen experience
ObjectiveTo study the quality and continuity of treatment in the Acute Medicines Assessment Unit (AMAU) with regard to empirical prescription of antibiotics, mode of administration, adherence to ward antibiotic policy, as well as collection, awareness and utilization of microbiological investigations.MethodsA prospective study over a 3-month period at the AMAU, Aberdeen Royal Infirmary (ARI), a teaching hospital in north-eastern Scotland, was performed. The study included all patients started on empirical antibiotics on admission to the AMAU and followed up until their discharge.ResultsOf 1303 patients admitted, 221 (17%) were started on empirical antibiotics. This was in accordance with hospital antibiotic policy in 52% of cases. Appropriate specimens were taken from 77% of patients. Culture results showed that 29% (n = 65) of the patients had clinically significant growth of organisms. Of the 65 patients with clinically significant culture results, 49% (n = 32) were on an inappropriate empirical regimen. In 55%, the medication was not changed to a more appropriate antibiotic. In 72% of the patients with a negative culture, the culture report had no obvious effect on the duration or type of antibiotic being administered. Intravenous antibiotics were used in 60% of patients.ConclusionThis study demonstrates a significant overuse of antibiotics, especially intravenous forms, despite a paucity of positive sepsis parameters and chest X-ray findings in these patients The duration of treatment could be shortened and an early switch policy introduced if culture results and sepsis profiles were taken into consideration, as there was a large number of unproven infections. Suggestions are made about how these improvements in prescribing could be made within the current administrative set-up of AMAUs
The Argentinian version of the cognitive fusion questionnaire:Psychometric properties and the role of cognitive fusion as a predictor of pathological worry
The Cognitive Fusion Questionnaire (CFQ) consists in an instrument used to measure cognitive fusion. Cognitive fusion can be described as a core process in the psychopathology model of Acceptance and Commitment Therapy (ACT). The purpose of this study was to adapt the CFQ for the Argentinian population, to validate it through a confirmatory factor analysis together with the analysis of its psychometric properties in a local community sample, and to look into the role cognitive fusion plays as a predictor of pathological worry. Three hundred and thirty-three adult participants filled out not only the Argentinian adaptation of the questionnaire (CFQ-VA) but also measures that assessed psychological inflexibility, worry, rumination, mindfulness and psychological well-being. The results indicate that the CFQ’s one-factor structure was confirmed. The instrument showed adequate internal consistency, good temporal stability, and significant associations in the expected directions with relevant selected constructs indicating adequate criterion validity. Also, cognitive fusion emerged as a good predictor of worry. In conclusion, the findings confirm that the Argentinian adaptation of the CFQ presents solid psychometric properties.Fil: José Quintero, Paula S.. Fundación Foro; Argentina. Universidad de Flores; ArgentinaFil: RodrÃguez Biglieri, Ricardo. Universidad de la Marina Mercante; Argentina. Instituto de Terapia Cognitivo Conductual; ArgentinaFil: Etchezahar, Edgardo Daniel. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Centro Interdisciplinario de Investigaciones en PsicologÃa Matemática y Experimental Dr. Horacio J. A. Rimoldi; ArgentinaFil: Gillanders, David T.. University of Edinburgh; Reino Unid
IL-6 selectively suppresses cDC1 specification via C/EBPβ
Cytokines produced in association with tumors can impair antitumor immune responses by reducing the abundance of type 1 conventional dendritic cells (cDC1), but the mechanism remains unclear. Here, we show that tumor-derived IL-6 generally reduces cDC development but selectively impairs cDC1 development in both murine and human systems through the induction of C/EBPβ in the common dendritic cell progenitor (CDP). C/EBPβ and NFIL3 compete for binding to sites in the Zeb2 -165 kb enhancer and support or repress Zeb2 expression, respectively. At homeostasis, pre-cDC1 specification occurs upon Nfil3 induction and consequent Zeb2 suppression. However, IL-6 strongly induces C/EBPβ expression in CDPs. Importantly, the ability of IL-6 to impair cDC development is dependent on the presence of C/EBPβ binding sites in the Zeb2 -165 kb enhancer, as this effect is lost in Δ1+2+3 mutant mice in which these binding sites are mutated. These results explain how tumor-associated IL-6 suppresses cDC1 development and suggest therapeutic approaches preventing abnormal C/EBPβ induction in CDPs may help reestablish cDC1 development to enhance antitumor immunity
Eight habitats, 38 threats and 55 experts: Assessing ecological risk in a multi-use marine region
Published: May 10, 2017Identifying the relative risk human activities pose to a habitat, and the ecosystem services they provide, can guide management prioritisation and resource allocation. Using a combination of expert elicitation to assess the probable effect of a threat and existing data to assess the level of threat exposure, we conducted a risk assessment for 38 human-mediated threats to eight marine habitats (totalling 304 threat-habitat combinations) in Spencer Gulf, Australia. We developed a score-based survey to collate expert opinion and assess the relative effect of each threat to each habitat, as well as a novel and independent measure of knowledge-based uncertainty. Fifty-five experts representing multiple sectors and institutions participated in the study, with 6 to 15 survey responses per habitat (n = 81 surveys). We identified key threats specific to each habitat; overall, climate change threats received the highest risk rankings, with nutrient discharge identified as a key local-scale stressor. Invasive species and most fishing-related threats, which are commonly identified as major threats to the marine environment, were ranked as low-tier threats to Spencer Gulf, emphasising the importance of regionally-relevant assessments. Further, we identified critical knowledge gaps and quantified uncertainty scores for each risk. Our approach will facilitate prioritisation of resource allocation in a region of increasing social, economic and environmental importance, and can be applied to marine regions where empirical data are lacking.Zoë A. Doubleday, Alice R. Jones, Marty R. Deveney, Tim M. Ward, Bronwyn M. Gillander
Direct measurement of stellar angular diameters by the VERITAS Cherenkov Telescopes
The angular size of a star is a critical factor in determining its basic
properties. Direct measurement of stellar angular diameters is difficult: at
interstellar distances stars are generally too small to resolve by any
individual imaging telescope. This fundamental limitation can be overcome by
studying the diffraction pattern in the shadow cast when an asteroid occults a
star, but only when the photometric uncertainty is smaller than the noise added
by atmospheric scintillation. Atmospheric Cherenkov telescopes used for
particle astrophysics observations have not generally been exploited for
optical astronomy due to the modest optical quality of the mirror surface.
However, their large mirror area makes them well suited for such
high-time-resolution precision photometry measurements. Here we report two
occultations of stars observed by the VERITAS Cherenkov telescopes with
millisecond sampling, from which we are able to provide a direct measurement of
the occulted stars' angular diameter at the milliarcsecond scale.
This is a resolution never achieved before with optical measurements and
represents an order of magnitude improvement over the equivalent lunar
occultation method. We compare the resulting stellar radius with empirically
derived estimates from temperature and brightness measurements, confirming the
latter can be biased for stars with ambiguous stellar classifications.Comment: Accepted for publication in Nature Astronom
- …