1,991 research outputs found
Performance evaluation of novel SiPM for medical imaging applications
Silicon Photomultiplier (SiPM) detectors are investigated
world-wide as a suitable replacement for the conventional
vacuum based PhotoMultiplier Tube (PMT) and are enabling
applications otherwise not possible with PMT detectors. Progress
in recent years has been substantial with SiPM detectors pushing
the boundaries in energy and time resolution as well as photon
detection efficiency and active surface area. In this paper we
report on the performance of a gamma detector comprising latest
generation SiPM detectors from SensL coupled to novel Cerium
doped Gd3Al2Ga3O12 (GAGG) scintillators from Furukawa,
Japan. Both 3mm�3mm N-on-P and P-on-N SiPM detectors have
been optically coupled to 3mm�3mm�30mm crystals. An energy
resolution (662 keV Cs-137) of 9.4% has been measured for
GAGG crystal coupled to a 3mm�3mm N-on-P SiPM detector
Cardiac Depression Scale: Mokken scaling in heart failure patients
Background: There is a high prevalence of depression in patients with heart failure (HF) that is associated with worsening prognosis. The value of using a reliable and valid instrument to measure depression in this population is therefore essential. We validated the Cardiac Depression Scale (CDS) in heart failure patients using a model of ordinal unidimensional measurement known as Mokken scaling. Findings: We administered in face-to-face interviews the CDS to 603 patients with HF. Data were analysed using Mokken scale analysis. Items of the CDS formed a statistically significant unidimensional Mokken scale of low strength (H<0.40) and high reliability (Rho>0.8). Conclusions: The CDS has a hierarchy of items which can be interpreted in terms of the increasingly serious effects of depression occurring as a result of HF. Identifying an appropriate instrument to measure depression in patients with HF allows for early identification and better medical management. Keywords: Cardiac Depression Scale, Heart failure, Depression, Mokken scalin
Age and size at maturity: sex, environmental variability and developmental thresholds
In most organisms, transitions between different life-history stages occur later and at smaller sizes as growth conditions deteriorate. Day and Rowe recently proposed that this pattern could be explained by the existence of developmental thresholds (minimum sizes or levels of condition below which transitions are unable to proceed). The developmental-threshold model predicts that the reaction norm of age and size at maturity will rotate in an anticlockwise manner from positive to a shallow negative slope if: (i) initial body size or condition is reduced; and/or (ii) some individuals encounter poor growth conditions at increasingly early developmental stages. We tested these predictions by rearing replicated populations of soil mites Sancassania berlesei (Michael) under different growth conditions. High-food environments produced a vertical relationship between age and size at maturity. The slope became increasingly shallow as food was reduced. By contrast, high food in the maternal environment reduced the slope of the reaction norm of age and size at maturity, whereas low food increased it. Overall, the reaction norm of age and size at maturity in S. berlesei was significantly nonlinear and differed for males and females. We describe how growth conditions, mother's environment and sex determine age and size at maturity in S. berlesei
Note on the hydrodynamic description of thin nematic films: strong anchoring model
We discuss the long-wave hydrodynamic model for a thin film of nematic liquid
crystal in the limit of strong anchoring at the free surface and at the
substrate. We rigorously clarify how the elastic energy enters the evolution
equation for the film thickness in order to provide a solid basis for further
investigation: several conflicting models exist in the literature that predict
qualitatively different behaviour. We consolidate the various approaches and
show that the long-wave model derived through an asymptotic expansion of the
full nemato-hydrodynamic equations with consistent boundary conditions agrees
with the model one obtains by employing a thermodynamically motivated gradient
dynamics formulation based on an underlying free energy functional. As a
result, we find that in the case of strong anchoring the elastic distortion
energy is always stabilising. To support the discussion in the main part of the
paper, an appendix gives the full derivation of the evolution equation for the
film thickness via asymptotic expansion
Perspectives on environment and human health:an editorial
Human health and wellbeing are intimately linked to the state of the environment [...]</jats:p
Logging While Drilling Via Autonomous Sonde
We present a method of geophysical logging while tripping drill rods to produce logs similar to wireline logs. The process is autinmous in that it does not require any significant changes by the driller and does not require any modifications to the drill rig. Using starting depth, rod length, and sensors on the sonde a geophysical log can be created when the drill rods are retreived upon hole completion. Thus, this methodology is very suitable for slimhole and diamond drilling methods that do not case the completed hole. Such holes often collapse and are too expensive to log via wireline logging
Current Fertility Status Does Not Predict Sociosexual Attitudes and Desires in Normally Ovulating Women
Previous research has found that women at peak fertility show greater interest in extra-pair sex. However, recent replications have failed to detect this effect. In this study, we add to this ongoing debate by testing whether sociosexuality (the willingness to have sex in the absence of commitment) is higher in women who are at peak fertility. A sample of normally ovulating women (N = 773) completed a measure of sociosexuality and had their current fertility status estimated using the backward counting method. Contrary to our hypothesis, current fertility was unrelated to sociosexual attitudes and desires, even when relationship status was included as a moderator. These findings raise further doubts about the association between fertility and desire for extra-pair sex
The influence of magazines on men: normalizing and challenging young men’s prejudice with “lads’ mags”
Social psychologists have argued that popular UK and USA men’s magazines known as lads’ mags have normalized hostile sexism among young men. Three studies develop this argument. First, a survey of 423 young UK men found that ambivalent sexism predicted attitudes toward the consumption of lads’ mags, but not other forms of direct sexual consumption (paying for sex or patronizing strip clubs). Second, Study 2 (N = 81) found that young men low in sexism rated sexist jokes as less hostile towards women, but not as either funnier nor more ironic, when those jokes were presented within a lads’ mags context. These findings refute the idea that young men readily read lads’ mags’ sexism as ironic or ‘harmless fun.’ They show instead that placing sexist jokes in lads’ mags contexts makes them appear less hostile. The third study (N = 275) demonstrated that young men perceived lads’ mags as less legitimate after attempting to distinguish the contents of lads’ mags from rapists’ legitimations of their crimes. Implications for contemporary studies of masculinities and consumption are discussed
Mechanism of Vanadium Leaching during Surface Weathering of Basic Oxygen Furnace Steel Slag Blocks: A Microfocus X-ray Absorption Spectroscopy and Electron Microscopy Study
© 2017 American Chemical Society. Basic oxygen furnace (BOF) steelmaking slag is enriched in potentially toxic V which may become mobilized in high pH leachate during weathering. BOF slag was weathered under aerated and air-excluded conditions for 6 months prior to SEM/EDS and μXANES analysis to determine V host phases and speciation in both primary and secondary phases. Leached blocks show development of an altered region in which free lime and dicalcium silicate phases were absent and Ca-Si-H was precipitated (CaCO 3 was also present under aerated conditions). μXANES analyses show that V was released to solution as V(V) during dicalcium silicate dissolution and some V was incorporated into neo-formed Ca-Si-H. Higher V concentrations were observed in leachate under aerated conditions than in the air-excluded leaching experiment. Aqueous V concentrations were controlled by Ca 3 (VO 4 ) 2 solubility, which demonstrate an inverse relationship between Ca and V concentrations. Under air-excluded conditions Ca concentrations were controlled by dicalcium silicate dissolution and Ca-Si-H precipitation, leading to relatively high Ca and correspondingly low V concentrations. Formation of CaCO 3 under aerated conditions provided a sink for aqueous Ca, allowing higher V concentrations limited by kinetic dissolution rates of dicalcium silicate. Thus, V release may be slowed by the precipitation of secondary phases in the altered region, improving the prospects for slag reuse
Perspectives on environment and human health: an editorial
Human health and wellbeing are intimately linked to the state of the environment [...]This editorial work received from the European Union through the European Regional Development Fund based on COMPETE 2020 (Programa Operacional da Competitividade e Internacionalização) and projects ICT UIDB/04683/2020 and UIDP/04683/2020
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