5,359 research outputs found
Deciduous Trees of Minnesota: a Winter Key
Keys are provided for the identification in winter condition of Minnesota\u27s native deciduous trees and also those commonly cultivated. A labelled plate of illustrations accompanies the keys, as does a brief selected reference list
To Bat or Not to Bat: An Examination of Contest Rules in Day-night Limited Overs Cricket
The tradition of tossing a coin to decide who bats first in a cricket match introduces a randomly-assigned advantage to one team that is unique in sporting contests. In this paper we develop previous work on this issue by examining the impact of the toss on outcomes of day-night one day international games explicitly allowing for relative team quality. We estimate conditional logit models of outcomes using data from day-night internationals played between 1979 and 2005. Other things equal, we find that winning the toss and batting increases the probability of winning by 31%. In contrast, winning the toss does not appear to confer any advantage if the team choose to bowl first.cricket, contest rules, match results, competitive balance, outcome uncertainty
Low-frequency local field potentials in primate motor cortex and their application to neural interfaces
PhD ThesisFor patients with spinal cord injury and paralysis, there are currently very limited options for
clinical therapy. Brain-machine interfaces (BMIs) are neuroprosthetic devices that are being
developed to record from the motor cortex in such patients, bypass the spinal lesion, and use
decoded signals to control an effector, such as a prosthetic limb.
The ideal BMI would be durable, reliable, totally predictable, fully-implantable, and have
generous battery life. Current, state-of-the-art BMIs are limited in all of these domains; partly
because the typical signals used—neuronal action potentials, or ‘spikes’—are very susceptible
to micro-movement of recording electrodes. Recording spikes from the same neurons over
many months is therefore difficult, and decoder behaviour may be unpredictable from day-today. Spikes also need to be digitized at high frequencies (~104 Hz) and heavily processed. As
a result, devices are energy-hungry and difficult to miniaturise. Low-frequency local field
potentials (lf-LFPs; < 5 Hz) are an alternative cortical signal. They are more stable and can be
captured and processed at much lower frequencies (~101 Hz).
Here we investigate rhythmical lf-LFP activity, related to the firing of local cortical neurons,
during isometric wrist movements in Rhesus macaques. Multichannel spike-related slow
potentials (SRSPs) can be used to accurately decode the firing rates of individual motor
cortical neurons, and subjects can control a BMI task using this synthetic signal, as if they
were controlling the actual firing rate. Lf-LFP–based firing rate estimates are stable over time
– even once actual spike recordings have been lost. Furthermore, the dynamics of lf-LFPs are
distinctive enough, that an unsupervised approach can be used to train a decoder to extract
movement-related features for use in biofeedback BMIs. Novel electrode designs may help us
optimise the recording of these signals, and facilitate progress towards a new generation of
robust, implantable BMIs for patients.Research Studentship from the MRC, and Andy Jackson’s laboratory
(hence this work) is supported by the Wellcome Trust
An Empirical Analysis of UK House Price Risk Variation by Property Type
This paper examines the different risk and return profiles of four different property types in England and Wales, both nationally and by region. The property types include flats, terraced houses, semi-detached and detached houses. Motivated by the ICAPM approach of Scruggs (1998) and using an EGARCH in mean model, we find evidence of a positive risk-return relationship, with particular regard to terraced and semi-detached housing, as well as asymmetric adjustment, suggesting that mid-range housing is the property type most like other risk-based assets, which could be due to these property types being the most popular with buy-to-let investors. We also find that this relationship differs across property types, as has previously been found across regions.publishersversionPeer reviewe
Alternative Cropping Systems for Traditional Monoculture Wheat Acres in the Southern Plains for Two Farm Sizes
The economics of five alternative crop production systems for the Southern Plains winter wheat production region, for both conventional tillage and no-till, for two farm sizes, was determined. Yield data were obtained from a three-year experiment conducted on three farm fields in the region. Tillage costs differ across farm size.Crop Production/Industries, Farm Management,
Effects of Vitamin E and Aspirin on Disease in Cattle
Author Institution (Bray): Department of Human Nutrition and Food Management, The Ohio State University; Author Institution (Wittum): Department of Veterinary Preventative Medicine, The Ohio State Universit
The First Spectrum of the Coldest Brown Dwarf
The recently discovered brown dwarf WISE 0855 presents our first opportunity
to directly study an object outside the Solar System that is nearly as cold as
our own gas giant planets. However the traditional methodology for
characterizing brown dwarfs---near infrared spectroscopy---is not currently
feasible as WISE 0855 is too cold and faint. To characterize this frozen
extrasolar world we obtained a 4.5-5.2 m spectrum, the same bandpass long
used to study Jupiter's deep thermal emission. Our spectrum reveals the
presence of atmospheric water vapor and clouds, with an absorption profile that
is strikingly similar to Jupiter. The spectrum is high enough quality to allow
the investigation of dynamical and chemical processes that have long been
studied in Jupiter's atmosphere, but now on an extrasolar world.Comment: submitted to ApJ
Vacuum polarisation on asymptotically anti-de Sitter spacetimes
This thesis considers a real, massless, conformally coupled scalar field propagating on the covering space of four-dimensional anti-de Sitter space (CadS) and on four-dimensional Schwarzschild-anti de Sitter space (SadS).
Numerical results for the vacuum polarisation are obtained in CadS with Robin conditions imposed at the boundary. A proof is given to demonstrate that results approach the same finite limit at the boundary unless Dirichlet conditions are imposed.
Numerical results for the vacuum polarisation are obtained in SadS with Dirichlet conditions imposed at the boundary, using the extended coordinates method of renormalisation. These results are then extended for Robin
boundary conditions, where we see qualitatively similar behaviour to that observed in CadS
Requirement for the eIF4E Binding Proteins for the Synergistic Down-Regulation of Protein Synthesis by Hypertonic Conditions and mTOR Inhibition.
The protein kinase mammalian target of rapamycin (mTOR) regulates the phosphorylation and activity of several proteins that have the potential to control translation, including p70S6 kinase and the eIF4E binding proteins 4E-BP1 and 4E-BP2. In spite of this, in exponentially growing cells overall protein synthesis is often resistant to mTOR inhibitors. We report here that sensitivity of wild-type mouse embryonic fibroblasts (MEFs) to mTOR inhibitors can be greatly increased when the cells are subjected to the physiological stress imposed by hypertonic conditions. In contrast, protein synthesis in MEFs with a double knockout of 4E-BP1 and 4E-BP2 remains resistant to mTOR inhibitors under these conditions. Phosphorylation of p70S6 kinase and protein kinase B (Akt) is blocked by the mTOR inhibitor Ku0063794 equally well in both wild-type and 4E-BP knockout cells, under both normal and hypertonic conditions. The response of protein synthesis to hypertonic stress itself does not require the 4E-BPs. These data suggest that under certain stress conditions: (i) translation has a greater requirement for mTOR activity and (ii) there is an absolute requirement for the 4E-BPs for regulation by mTOR. Importantly, dephosphorylation of p70S6 kinase and Akt is not sufficient to affect protein synthesis acutely
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