1,599 research outputs found
Low-temperature plasma technology as part of a closed-loop resource management system
The results of this testing indicate that the agitated low-temperature plasma reactor system successfully converted carbon, hydrogen, and nitrogen into gaseous products at residence times that were about ten times shorter than those achieved by stationary processing. The inorganic matrix present was virtually unchanged by the processing technique. It was concluded that this processing technique is feasible for use as part of a close-looped processing resource management system
Australian state influenza notifications and school closures in 2019 [version 1; peer review: 2 approved with reservations]
Intraspecific competition in the speckled wood butterfly Pararge aegeria: Effect of rearing density and gender on larval life history
In insects, the outcome of intraspecific competition for food during development depends primarily upon larval density and larval sex, but effects will also depend on the particular trait under consideration and the species under study. Experimental manipulations of larval densities of a Madeiran population of the speckled wood butterfly Pararge aegeria confirmed that intraspecific competition affected growth. As densities increased P. aegeria adults were smaller and larval development periods were longer. Sexes responded differently to rearing density. Females were more adversely affected by high density than males, resulting in females having smaller masses at pupation. Survivorship was significantly higher for larvae reared at low densities. No density effect on adult sex ratios was observed. Intraspecific competition during the larval stage would appear to carry a higher cost for females than males. This may confer double disadvantage since females are dependent on their larval derived resources for reproduction as they have little opportunity to accumulate additional resources as adults. This suggests that shortages of larval food could affect fecundity directly. Males, however, may be able to compensate for a small size by feeding as adults and/or by altering their mate location tactics
D-dimer threshold increase with pretest probability unlikely for pulmonary embolism to decrease unnecessary computerized tomographic pulmonary angiography
Background:â Increasing the threshold to define a positive D-dimer could reduce unnecessary computed tomographic pulmonary angiography (CTPA) for a suspected pulmonary embolism (PE) but might increase rates of a missed PE and missed pneumonia, the most common non-thromboembolic diagnosis seen on CTPA.
Objective:â Measure the effect of doubling the standard D-dimer threshold for âPE unlikelyâ Revised Geneva (RGS) or Wellsâ scores on the exclusion rate, frequency and size of a missed PE and missed pneumonia.
Methods:â Patients evaluated for a suspected PE with 64-channel CTPA were prospectively enrolled from emergency departments (EDs) and inpatient units of four hospitals. Pretest probability data were collected in real time and the D-dimer was measured in a central laboratory. Criterion standard was CPTA interpretation by two independent radiologists combined with clinical outcome at 30 days.
Results:â Of 678 patients enrolled, 126 (19%) were PE+ and 93 (14%) had pneumonia. Use of either Wellsâ †4 or RGS †6 produced similar results. For example, with RGS †6 and standard threshold (< 500 ng mLâ1), D-dimer was negative in 110/678 (16%), and 4/110 were PE+ (posterior probability 3.8%) and 9/110 (8.2%) had pneumonia. With RGS †6 and a threshold < 1000 ng mLâ1, D-dimer was negative in 208/678 (31%) and 11/208 (5.3%) were PE+, but 10/11 missed PEs were subsegmental and none had concomitant DVT. Pneumonia was found in 12/208 (5.4%) with RGS †6 and D-dimer < 1000 ng mLâ1.
Conclusions:â Doubling the threshold for a positive D-dimer with a PE unlikely pretest probability could reduce CTPA scanning with a slightly increased risk of missed isolated subsegmental PE, and no increase in rate of missed pneumonia
Calibration and application of the ChemcatcherÂź passive sampler for monitoring acidic herbicides in the River Exe, UK catchment
Response of a low elevation carbonate lake in the Yucatan Peninsula (Mexico) to climatic and human forcings
The importance of climate change, specifically drought, across the Maya region in the northern Neotropics, remains a topic of lively debate. Part of this discussion hinges on the coherency of response to climatic variability across different archives and proxies. In this paper we present a 6600-year palaeolimnological record from Yaal Chac, a carbonate lake (known locally as a cenote) in the northern lowlands of the Yucatan Peninsula, 2â°), but show no covariation with ÎŽ13C. A major transition occurs at ca. 4360 cal yr BP, with a change to generally more organic sediments and increased variability in all proxies. Although direct evidence for anthropogenic activity in the Yaal Chac catchment is limited, it seems feasible that human impact was affecting the system. Comparison with other records from the Northern Maya lowlands and the wider region shows little coherence in the mid Holocene, when Yaal Chac seems to have been quite stable, but possibly responsive to increased climatic seasonality, driving the production of seasonal laminae. In the late Holocene, when the climate was generally more variable, there is more coherence between Yaal Chac and other regional records, including the so called Pan Caribbean Dry Period (3500â2500 cal yr BP) and the droughts of the late Pre-Classic period (1800â1600 cal yr BP). The Yaal Chac record shows no evidence of drought at the time of either the Maya âhiatusâ or the Maya âcollapseâ of the Terminal Classic, but does record drying from the 14th to 19th centuries CE, in keeping with other proxy and historical records. This new record from Yaal Chac highlights the spatial variability of responses to climate forcings and the importance of recognising individual system sensitivity
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Interpretation of ambiguous situations: evidence for a dissociation between social and physical threat in Williams syndrome
There is increasing evidence that Williams syndrome (WS) is associated with elevated anxiety that is non-social in nature, including generalised anxiety and fears. To date very little research has examined the cognitive processes associated with this anxiety. In the present research, attentional bias for non-social threatening images in WS was examined using a dot-probe paradigm. Participants were 16 individuals with WS aged between 13 and 34 years and two groups of typically developing controls matched to the WS group on chronological age and attentional control ability respectively. The WS group exhibited a significant attention bias towards threatening images. In contrast, no bias was found for group matched on attentional control and a slight bias away from threat was found in the chronological age matched group. The results are contrasted with recent findings suggesting that individuals with WS do not show an attention bias for threatening faces and discussed in relation to neuroimaging research showing elevated amygdala activation in response to threatening non-social scenes in WS
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Shared compatibility of ectomycorrhizae on Pseudotsuga menziesii and Betula papyrifera seedlings grown in mixture in soils from southern British Columbia
Seedlings of Pseudotsuga menziesii (Mirb.) Franco and Betula papyrifera Marsh. were grown in the greenhouse in monoculture and dual culture in soils collected from a young mixed species plantation in the southern interior of British Columbia. The objectives of the study were (i) to evaluate the ability of P. menziesii and B. papyrifera to share compatible ectomycorrhizal fungi in order to assess their potential for hyphal linkages and (ii) to study the influence of neighboring seedlings on ectomycorrhizae occurrence. Eleven ectomycorrhizal morphotypes were recognized, seven of which P. menziesii and B. papyrifera seedlings shared in common over 90% of their root tips. The abundance and frequency of Rhizopogon, E-strain I, and Tuber on P. menziesii, and the frequency of Lactarius, Hebeloma, and Cenococcum on B. papyrifera, were affected by the presence of a neighboring seedling. The number of ectomycorrhizal morphotypes shared in common and colonization of root tips by common types were slightly greater when P. menziesii and B. papyrifera were grown in dual culture rather than in monoculture
The writing on the wall: the concealed communities of the East Yorkshire horselads
This paper examines the graffiti found within late nineteenth and early-twentieth century farm buildings in the Wolds of East Yorkshire. It suggests that the graffiti were created by a group of young men at the bottom of the social hierarchy - the horselads â and was one of the ways in which they constructed a distinctive sense of communal identity, at a particular stage in their lives. Whilst it tells us much about changing agricultural regimes and social structures, it also informs us about experiences and attitudes often hidden from official histories and biographies. In this way, the graffiti are argued to inform our understanding, not only of a concealed community, but also about their hidden histor
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