52 research outputs found

    TRY plant trait database – enhanced coverage and open access

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    Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

    Narrowband Searches for Continuous and Long-duration Transient Gravitational Waves from Known Pulsars in the LIGO-Virgo Third Observing Run

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    Isolated neutron stars that are asymmetric with respect to their spin axis are possible sources of detectable continuous gravitational waves. This paper presents a fully coherent search for such signals from eighteen pulsars in data from LIGO and Virgo's third observing run (O3). For known pulsars, efficient and sensitive matched-filter searches can be carried out if one assumes the gravitational radiation is phase-locked to the electromagnetic emission. In the search presented here, we relax this assumption and allow both the frequency and the time derivative of the frequency of the gravitational waves to vary in a small range around those inferred from electromagnetic observations. We find no evidence for continuous gravitational waves, and set upper limits on the strain amplitude for each target. These limits are more constraining for seven of the targets than the spin-down limit defined by ascribing all rotational energy loss to gravitational radiation. In an additional search, we look in O3 data for long-duration (hours-months) transient gravitational waves in the aftermath of pulsar glitches for six targets with a total of nine glitches. We report two marginal outliers from this search, but find no clear evidence for such emission either. The resulting duration-dependent strain upper limits do not surpass indirect energy constraints for any of these targets. © 2022. The Author(s). Published by the American Astronomical Society

    Positron emission tomography studies of the human and disease

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    Available from British Library Document Supply Centre-DSC:DXN029300 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

    Improving the quality of waste-derived char by removing ash

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    This study characterized and removed ash from waste-derived char to improve the quality of char as fuel. Municipal solid waste (MSW) and automobile shredder residue (ASR) were carbonized at 450 ℃ and at 500 ℃ respectively in a rotary kiln with a nitrogen atmosphere for 1 h. MSW and ASR char were subjected to sieving and pulverization-sieving to screen incombustibles and the ash-rich fraction, after which float–sink separation, froth floatation, and oil agglomeration were applied to remove ash from the char. The established target quality was less than 30% ash content and more than 20000 kJ/kg heating value. However, the rate of combustibles recovery had to be lowered to produce a good quality of char along with a high heating value. MSW char attained the targeted quality level using froth floatation or oil agglomeration whereas neither separation method was able to make ASR-derived char satisfy the target. Based on the assumption that particle properties of char are determined by the weight ratio of combustibles and ash, the densities of combustibles and ash in char were estimated using the results of float–sink separation, X-ray diffraction (XRD) analysis, and elemental content. To verify the above assumption, an energy dispersive X-ray/scanning electron microscope (EDX/SEM) analyzer was used to observe char particles

    Optical Mapping of the Frontal Cortex During a Surgical Knot-tying Task, a Feasibility Study

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    Functional neuroimaging technologies have transformed cognitive neuroscience by enhancing our understanding of the functional sub-classification of brain regions. Whilst a number of studies have explored brain activation associated with complex motor skills, few of the tasks investigated have had direct occupational relevance. To date there have been no functional studies involving surgeons or motor paradigms with relevance to surgery. This study reports on the feasibility of Near Infrared Spectroscopy (NIRS) for studying subjects performing realistic surgical tasks in a laboratory setting. We observed a recognisable haemodynamic response to brain activation, which was reliable and repeatable in subjects despite days without practice on the task. A wide range of prefrontal activation was observed, thought to reflect considerable variation in the cognitive resources allocated to complete a highly attention demanding surgical task
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