102,347 research outputs found
Hoad, G R W, NX36644
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/392545Surname: HOAD. Given Name(s) or Initials: G R W. Military Service Number or Last Known Location: NX36644. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 35934.210315
Item: [2016.0049.24838] "Hoad, G R W, NX36644
Genetic and phenotypic parameters for temperament in weaned lambs
No full textJ. E. Hocking Edwards, F. D. Brien, M. L. Hebart, G. N. Hinch, J. Hoad, K. W. Hart, G. Gaunt, M. Robertson, G. Refshuage and T. Bird-Gardine
If all you have is a hammer, everything looks like a nail: spectral trends as a measure of ecological change in the Arctic
No full textThe Arctic is warming four times faster than lower latitudes. Observations from spatially limited tundra field sites show increased vegetation growth, expansion of woody shrub cover, decreased snow cover and extreme permafrost thaw disturbances. Satellite imagery is fundamental to our understanding of these land-surface changes across the Arctic and, thereby, to our ability to predict feedbacks to global climate. Positive trends in the satellite-derived normalised difference vegetation index (NDVI) have been broadly observed and attributed to increased vegetation productivity, instigating a discourse of Arctic greening, while negative trends, or browning, are less common and broader in attribution. However, methodological issues such as spectral mixing within satellite pixels, the saturation of the NDVI, and the period of the analyses have emerged as a source of significant uncertainty in the detection and ecological interpretation of spectral greening and browning trends. In this thesis, I use high-resolution drone and satellite imagery to assess the effect of snow, fractional vegetation cover, and permafrost thaw slumps on our ability to detect and interpret spectral trends.
Snow cover has decreased in extent and duration across much of the Arctic but is poorly accounted for in spectral trend analyses. By using high-resolution drone imagery from one Arctic and one sub-Arctic site, I found that fine-scale snow persistence within satellite pixels is associated with both reduced magnitude and delayed timing of annual peak NDVI, the base metric of spectral trend analyses. These findings indicate that unaccounted changes in fine-scale snow persistence may contribute to Arctic spectral greening and browning trends through either biotic responses of vegetation to snow cover or abiotic integration of snow within the estimated peak NDVI. Across the Arctic, changing snow persistence may drive both underestimation and overestimation of changes in vegetation productivity.
Fractional vegetation cover corresponds with spectral mixing and the saturation of the NDVI. However, vegetation cover is difficult to calculate at the scale of satellite pixels, and the relationship between vegetation cover and spectral trends therefore remains unknown. I found that spectral Sentinel-2 data can predict vegetation cover at a high-latitude and low-latitude tundra site, and subsequently observed that predicted vegetation cover differed significantly between pixels with and without spectral trends. These results suggest that a pixel’s vegetation cover may affect our ability to detect spectral trends, due to spectral mixing within low vegetation cover pixels and saturation of the NDVI within high vegetation cover pixels. Spatial variation in spectral greening and browning across the Arctic may, in places, reflect underlying patterns in fractional vegetation cover more than the presence or absence of vegetation change.
Permafrost disturbance events are an often-cited source of spectral browning, however, the effect of their timing and subsequent recovery on trend detection has received limited attention. I use a pan-Arctic dataset of retrogressive thaw slumps to examine the representation of permafrost disturbance events in spectral trends derived from Landsat imagery. I found that spectral browning occurred over less than half of the analysed thaw slumps (~49%) due to post-disturbance vegetation recovery and the time period of analysis. Ultimately, this may lead to an underestimation of permafrost disturbance-related change across the Arctic.
Together, my thesis findings demonstrate that spectral trend analyses, although familiar, are a somewhat blunt tool for inferring Arctic vegetation change from satellite imagery. Attributing spectral trends to field observations of ecological change is complicated by a lack of methodological nuance, where unaccounted variation in snow, vegetation cover and dynamic permafrost thaw disturbances may obscure the detection or interpretation of trends. Overall, this thesis highlights three confounding effects on spectral trend analyses that should be considered to improve future assessments of Arctic land-surface change
Bibliographie Hilarion G. Petzold 1958 – 2009 mit Anhang als Einführung
No full textDieses Archiv enthält die Gesamtbibliographie der Werke des Autors nebst einiger Texte „Über H. G. Petzold“ im Schlussteil der Bibliographie sowie einen Anhang mit einer Einführung in die Architektur des Werkes in seinem wissenslogischen Aufbau als Ausarbeitung seines „Tree of Science Modells“ (2007).This archive contains the complete bibliography of the author and some texts about H. G. Petzold, moreover an epilogue with an introduction to the architecture of the works in its epistemological structure and composition and as an elaborations of Petzold’s „Tree of Science Modell (2007).https://www.fpi-publikation.de/polyloge/01-2009-petzold-h-g-gesamtbibliographie-h-g-petzold-1958-2009-updating-november2009/peerReviewedpublishedVersio
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Understanding the components of specific weight in barley grains: opportunities for improving grain quality and processing efficiency.
No full textSpring barley is the primary cereal crop grown in Scotland, 35% of the crop is used
for malting and 55% for animal feed. There is a clear distinction between barley
destined for malting or feed, this is a result of the higher quality grain demanded for
malting and consequently a premium is paid for this. For example, in the UK during
September 2018 malting barley reached prices of £46/t more than that of feed barley.
Quality requirements for malting barley include: germination rate, per cent admixture,
nitrogen levels, cultivar, moisture content, uniformity, skinning level,
disease/weathering damage and specific weight (SW). Therefore different agronomic
approaches are taken when a grower is striving for either malting or feed barley. The
majority of these malting barley quality requirements are well understood, SW is well
established however its impact on malting outputs or efficiency are not well
understood. Specific weight is one of the longest standing measures of grain quality
for cereals and oilseeds, it is a measure of the weight of grain per unit volume and is
reported in kilograms per hectolitre (kg hl-1
). An increased SW is thought to be
beneficial for malt output. The aim of this thesis is to enhance the understanding of
SW as a measure of grain quality, and to establish what aspects of barley grain
determine this measure. Following establishing these grain traits, the aim is then to
relate these to the malting process and outputs, to understand how SW influences
malting. Firstly, SW has been demonstrated to have two components: grain density
and packing efficiency. This is a key part of the thesis, because both components can
change independently. Different grain parameters influence each of the components,
therefore both need to be considered together when investigating SW differences or
similarities between samples. The packing efficiency and grain density of nine spring
barley cultivars was investigated, this demonstrated that grain density contributed
48.5% to the variation in SW and packing efficiency 36.5% to the variation in SW. It was hypothesised that the packing efficiency of grains was primarily influenced by
grain morphometrics, and grain density influenced by composition. Investigating how
composition changes with grain density was investigated by first stratifying grains by
density, resulting in groups of grains with different densities. Compositional analyses
were then carried out on these groups which showed that grain nitrogen level and the
proportional volume of starch B-type granules contributed 47% to the observed
variation in grain density. Specific weight is also known to be affected by growing
conditions, with year to year variation observed. Such year-on-year variations might
be a result of changing climatic conditions between years, therefore the effect of a
moderate, but prolonged water stress was investigated under glasshouse conditions.
Plant development was altered by the stress, but SW was maintained through
compensatory mechanisms. To investigate how changes in SW affect malt quality
parameters, SW was manipulated through selection for different grain size and
weights. Specific weight was shown to be strongly correlated with the predicted spirit
yield and hot water extract of the malt. These are two fundamental measures of malt
quality. Grain density also correlated with these two measures, but packing efficiency
of the grains did not. This indicates that it is grain density rather than the packing
efficiency of the grain that is the beneficial component of SW for malting. Therefore if
breeding of elite malting cultivars is continued to enhance malt quality through
increasing SW, this should be done so through increasing the grain density
component rather than packing efficiency
Recommended from our members
3346: Samuel G. Freedman, author, 2013
No full textPhotograph of author Samuel G. Freedman, at NT Daily Slash meeting in the Mayborn School of Journalism at UNT
An unavoidable modulation? Sensory attention and human primary motor cortex excitability
No full textThe link between basic physiology and its modulation by cognitive states, such as attention, is poorly understood. A significant association becomes apparent when patients with movement disorders describe experiences with changing their attention focus and the fundamental effect that this has on their motor symptoms. Moreover, frequently used mental strategies for treating such patients, e.g. with task-specific dystonia, widely lack laboratory-based knowledge about physiological mechanisms. In this largely unexplored field, we looked at how the locus of attention, when it changed between internal (locus hand) and external (visual target), influenced excitability in the primary motor cortex (M1) in healthy humans. Intriguingly, both internal and external attention had the capacity to change M1 excitability. Both led to a reduced stimulation-induced GABA-related inhibition and a change in motor evoked potential size, i.e. an overall increased M1 excitability. These previously unreported findings indicated: (i) that cognitive state differentially interacted with M1 physiology, (ii) that our view of distraction (attention locus shifted towards external or distant location), which is used as a prevention or management strategy for use-dependent motor disorders, is too simple and currently unsupported for clinical application, and (iii) the physiological state reached through attention modulation represents an alternative explanation for frequently reported electrophysiology findings in neuropsychiatric disorders, such as an aberrant inhibition
The Right to Strike under the United States Constitution: Theory, Practice, and Possible Implications for Canada
No full textAnswering critics of the Canadian Supreme Court's judgment in B.C. Health, the author argues that the Court laid the foundation for a principled and durable doctrine protecting constitutional labour rights, one that goes directly to the heart of the matter — the inequality of workers’ power in the employment relation. In the author’s view, two paths could lead from B.C. Health to the recognition of Charter protec- tion for a right to strike: one that treats the right as an accessory to col- lective bargaining, and one that upholds the right directly on the basis of the Charter values of equality and participation. The author supports the latter approach, contending that constitutional rights should be defined in relation to fundamental values, in a way that is not contingent on time-bound or fact-sensitive assessments about the role of strikes within a particular collective bargaining regime. Although a Charter right to strike may involve the courts in difficult choices about when to defer to legislative policy decisions, and courts may lack the institutional capac- ity to deal effectively with labour law issues, the author points out that judges can look to ILO standards for expert guidance. Noting that the U.S. experience in this area might be of considerable use to Canadians, the author concludes by providing an overview of American case law concerning a constitutional right to strike.Peer reviewe
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