5,935 research outputs found
The Effect of Secret Clock Manipulation on 10 km Cycle Time Trial Performance.
The anticipatory RPE feedback model (Tucker 2009) proposes that during self paced exercise tasks, muscular work is continually regulated through comparison of a subconscious ‘template’ Rating of Perceived Exertion (RPE) that serves to protect against the development of catastrophic physiological failure, and a ‘conscious’ RPE that is generated through afferent feedback with regards to peripheral physiological status and through psychological inputs. The aim of this study was to investigate the effect of altering psychological inputs via incorrect time feedback on both RPE and performance during a series of maximal effort 10km cycle time trials. After task familiarisation, eight participants performed three separate time trials using their own cycle mounted onto the Kingcycle ergometer rig. Distance covered was available via large visual display along with elapsed time. On one occasion the display clock ran at the correct speed, but on two other occasions the clock manipulation was altered so that it ran either 10% too fast or 10% too slow. The order of the interventions was randomised. Although no significant differences were observed in total performance time, the magnitude of the endspurt participants were able to generate in the final 10% of the trial was significantly (P<0.01) greater during the slow clock trials than during the fast clock trials. Despite differences in pace distribution under each clock condition, a similar generally linear increase in RPE was observed throughout trials in all conditions. It is proposed that these findings lend support to the anticipatory RPE feedback model, and that altered psychological inputs probably act by influencing the fraction of metabolic reserve capacity that can be accessed during such trials
A common scheme for running NLO ep event generators
In this article we present a generic interface to several next-to-leading
order cross-section programs. This enables the user to implement his/her code
once and make cross-checks with different programs.Comment: 19 pages, Proceedings of Workshop on Monte Carlo Generators for HERA
Physics 1998/9
Grand Unification and Light Color-Octet Scalars at the LHC
We study the properties and production mechanisms of color-octet scalars at
the LHC. We focus on the single production of both charged and neutral members
of an (8,2)_1/2 doublet through bottom quark initial states. These channels
provide a window to the underlying Yukawa structure of the scalar sector.
Color-octet scalars naturally appear in grand unified theories based on the
SU(5) gauge symmetry. In the context of adjoint SU(5) these fields are expected
to be light to satisfy constraints coming from unification and proton decay,
and may have TeV-scale masses. One combination of their couplings is defined by
the relation between the down-quark and charged-lepton Yukawa couplings.
Observation of these states at the LHC gives an upper bound on the proton
lifetime if they truly arise from this grand unified theory. We demonstrate
that TeV-mass scalars can be observed over background at the LHC using boosted
top quark final states, and study how well the scalar Yukawa parameters can be
measured.Comment: 22 pages, LaTeX, 5 figures; typos corrected, references adde
Sialic acid acquisition in bacteria - one substrate many transporters
The sialic acids are a family of 9-carbon sugar acids found predominantly on the cell-surface glycans of humans and other animals within the Deuterostomes and are also used in the biology of a wide range of bacteria that often live in association with these animals. For many bacteria sialic acids are simply a convenient source of food, whereas for some pathogens they are also used in immune evasion strategies. Many bacteria that use sialic acids derive them from the environment and so are dependent on sialic acid uptake. In this mini-review I will describe the discovery and characterization of bacterial sialic acids transporters, revealing that they have evolved multiple times across multiple diverse families of transporters, including the ATP-binding cassette (ABC), tripartite ATP-independent periplasmic (TRAP), major facilitator superfamily (MFS) and sodium solute symporter (SSS) transporter families. In addition there is evidence for protein-mediated transport of sialic acids across the outer membrane of Gram negative bacteria, which can be coupled to periplasmic processing of different sialic acids to the most common form, β-D-N-acetylneuraminic acid (Neu5Ac) that is most frequently taken up into the cell
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Llanelly Parish, Breconshire : The Impact Of The Iron Industry On A Rural Welsh Parish, 1790-1890.
Perhaps understandably, most of the research undertaken into the growth of the South Wales coal and iron industries has concentrated on the major production areas such as Merthyr Tydfil. Llanelly parish, Breconshire, is situated to the north-east, at the very extremity of this industrial area, and has been largely ignored by historians. Yet, starting in the late eighteenth century, Llanelly parish underwent a rapid development owing to the expansion of the local iron industry, only for it to decline from around the middle of the nineteenth century. This study examines the demographic, economic, and social changes which the iron industry brought to this previously agricultural area, and the extent to which communities on the margin of the ironbelt were caught up in the industrial conflicts of the time. The thesis also investigates how this relatively small industrial settlement differed, if at all, from the larger industrial centres, and attempts to assess the consequences of the failure of the local ironworks in mid-century, by comparing the experiences of communities in the parish with those communities which continued to grow. Internal to the parish, the thesis also proffers reasons as to why some settlements never developed into proper townships, whereas others, most notably the town of Brynmawr, made that transition successfully
DEVELOPMENT OF A LOW PRESSURE-INDUCTIVELY COUPLED PLASMA-ION SOURCE FOR MASS SPECTROMETRY
A low pressure-inductively coupled plasma (LP-ICP) ion source has been investigated for
the production of atomic and molecular ions for mass spectrometry (MS). A dedicated LPICP-
MS was constructed, by modifying a Hewlett Packard mass selective detector, to
detect ions from the LP-ICP. The ion sampling interface and ion optics were designed using
established theory and the use of a computer simulation program. Perfluorotributylamine
was continuously introduced into the LP-ICP, via a molecular leak, and the ion sampling
interface, plasma forward power, and plasma gas flow rates, were optimised.
When the LP-ICP ion source was sustained at 6W with a gas flow of 6 ml min'* helium, and
iodobenzene and dibromobenzene, introduced via GC, only atomic signals for iodine and
bromine were observed. Detection limits were 4 and 76 pg for iodobenzene and
dibromobenzene respectively.
The addition of nitrogen to a LP helium ICP increased the molecular signal for
chlorobenzene, resulting in a detection limit of 2 pg. However, the addition of nitrogen did
not aid the production of molecular ions of iodobenzene and dibromobenzene.
When 0.07 ml min' of isobuiane was added to the LP-ICP mass spectra similar to those
obtained by an electron impact source were observed. However, on the addition of more
isobutane only the molecular ions (M*) for chlorobenzene, iodobenzene and
dibromobenzene were observed. The detection limits for the instrument operating in the
molecular mode were 100, 140 and 229 pg for chlorobenzene, iodobenzene and
dibromobenzene respectively.
Langmuir probe measurements were used to asses the effect of plasma forward power and
gas flow rate on the local plasma potential, ion number density, electron temperature and
electron number density within the LP-ICP. The local plasma potential varied from +50 V
to -20 V depending on the plasma conditions used. The ion and electron number densities
increased with increasing plasma power, with ion number densities of approximately 10^ cm'
^ and electron number densities of approximately at 10* cm ^ The effect of extra plasma gas
had a less distinct affect on the plasma excited species.
A plasma sustained at 6 W, 7 ml min'' helium and 1.8 ml min'* isobutane was used to
provide both quantitative and qualitative information of tetraethyllead in the standard
reference friel (NBS SRM 1637 II), with .the determined value of 13.06 ± 0.91 being in
good agreement with the certified value of 12.9 ± 0.07 expressed as total lead.British Petroleum International,
Sunbury-on-Thames, Middlesex, TW16 7L
Discussant\u27s response to \u27Under the spreading chestnut tree,\u27 accountants\u27 legal liability -- A historical perspective
https://egrove.olemiss.edu/dl_proceedings/1173/thumbnail.jp
Resonance Searches with an Updated Top Tagger
The performance of top taggers, for example in resonance searches, can be
significantly enhanced through an increased set of variables, with a special
focus on final-state radiation. We study the production and the decay of a
heavy gauge boson in the upcoming LHC run. For constant signal efficiency, the
multivariate analysis achieves an increased background rejection by up to a
factor 30 compared to our previous tagger. Based on this study and the
documentation in the Appendix we release a new HEPTopTagger2 for the upcoming
LHC run. It now includes an optimal choice of the size of the fat jet,
N-subjettiness, and different modes of Qjets.Comment: 26 page
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