36,928 research outputs found
Effects of muscle atrophy on motor control
As a biological tissue, muscle adapts to the demands of usage. One traditional way of assessing the extent of this adaptation has been to examine the effects of an altered-activity protocol on the physiological properties of muscles. However, in order to accurately interpret the changes associated with an activity pattern, it is necessary to employ an appropriate control model. A substantial literature exists which reports altered-use effects by comparing experimental observations with those from animals raised in small laboratory cages. Some evidence suggests that small-cage-reared animals actually represent a model of reduced use. For example, laboratory animals subjected to limited physical activity have shown resistance to insulin-induced glucose uptake which can be altered by exercise training. This project concerned itself with the basic mechanisms underlying muscle atrophy. Specifically, the project addressed the issue of the appropriateness of rats raised in conventional-sized cages as experimental models to examine this phenomenon. The project hypothesis was that rats raised in small cages are inappropriate models for the study of muscle atrophy. The experimental protocol involved: 1) raising two populations of rats, one group in conventional (small)-sized cages and the other group in a much larger (133x) cage, from weanling age (21 days) through to young adulthood (125 days); 2) comparison of size- and force-related characteristics of selected test muscles in an acute terminal paradigm
Dirac Magnetic Monopole Production from Photon Fusion in Proton Collisions
We calculate the lowest order cross--section for Dirac magnetic monopole
production from photon fusion in p p-bar collisions at sqrt{s}=1.96 TeV, p p
collisions at sqrt{s}=14 TeV, and we compare photon fusion with Drell--Yan (DY)
production. We find the total photon fusion cross--section is comparable with
DY at sqrt{s}=1.96 TeV and dominates DY by a factor ~50 at sqrt{s}=14 TeV. We
conclude that both the photon fusion and DY processes allow for a monopole mass
limit m>370 GeV based upon the null results of the recent monopole search at
the Collider Detector at Fermilab (CDF). We also conclude that photon fusion is
the leading production mechanism to be considered for direct monopole searches
at the Large Hadron Collider (LHC).Comment: 9 pages, 4 figures, minor correction, one reference adde
High-resolution UKIRT observations of circumnuclear star formation in M100
We present high-resolution, near-infrared imaging of the circumnuclear region
of the barred spiral galaxy M100 (=NGC 4321), accompanied by near-infrared
spectroscopy. We identify a total of 43 distinct regions in the K-band image,
and determine magnitudes and colours for 41 of them. By comparison with other
near-infrared maps we also derive colour excesses and K-band extinctions for
the knots. Combining the imaging and spectroscopic results, we conclude that
the knots are the result of bursts of star formation within the last 15-25 Myr.
We discuss the implications of these new results for our dynamical and
evolutionary understanding of this galaxy.Comment: 10 pages, 4 figures, uses mn-1.4.sty. Accepted for publication in
Monthly Notices of the Royal Astronomical Societ
Linguistic analysis of the valence, arousal and dominance of auditory hallucinations and internal thoughts in schizophrenia: Implications for psychoeducation and CBT
70% of patients with schizophrenia suffer from auditory verbal hallucinations (AVH) which are frequently described as distressing and disabling. The content of AVH, in relation to internal thought, has never been linguistically tested in a self-monitoring study. The aim of this preliminary study was to establish if there was a significant difference between AVH and inner thoughts on the key linguistic parameters of valence (pleasantness), dominance (control) and arousal (intensity of emotion produced). Six volunteers with a diagnosis of schizophrenia from voice hearing support groups produced real-time, detailed diaries of AVH and inner thoughts using randomised/fixed timers. Analysis of content was completed using an established linguistic database. AVH were significantly more unpleasant and controlling but not more emotionally arousing than inner thoughts. Psychoeducation around the experience of hallucination in schizophrenia should include information that the voices will be significantly more unpleasant and controlling than their own thoughts but not more emotionally arousing. CBT might therefore include the use of compassion focussed techniques to help with the unpleasantness of AVH and schema level techniques to improve coping with the dominance of AVH
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