642 research outputs found
Weakly compact operators and the strong* topology for a Banach space
Peer reviewedPublisher PD
Truncation of TRIM5 in the <i>Feliformia</i> explains the absence of retroviral restriction in cells of the domestic cat
TRIM5[alpha] mediates a potent retroviral restriction phenotype in diverse mammalian species. Here, we identify a TRIM5 transcript in cat cells with a truncated B30.2 capsid binding domain and ablated restrictive function which, remarkably, is conserved across the <i>Feliformia</i>. Cat TRIM5 displayed no restriction activity, but ectopic expression conferred a dominant negative effect against human TRIM5[alpha]. Our findings explain the absence of retroviral restriction in cat cells and suggest that disruption of the TRIM5 locus has arisen independently at least twice in the <i>Carnivora</i>, with implications concerning the evolution of the host and pathogen in this taxon
On the Sharpness and Bias of Quantum Effects
The question of quantifying the sharpness (or unsharpness) of a quantum
mechanical effect is investigated. Apart from sharpness, another property,
bias, is found to be relevant for the joint measurability or coexistence of two
effects. Measures of bias will be defined and examples given.Comment: Substantially expanded version, with new results and some proofs
correcte
Signal processing in local neuronal circuits based on activity-dependent noise and competition
We study the characteristics of weak signal detection by a recurrent neuronal
network with plastic synaptic coupling. It is shown that in the presence of an
asynchronous component in synaptic transmission, the network acquires
selectivity with respect to the frequency of weak periodic stimuli. For
non-periodic frequency-modulated stimuli, the response is quantified by the
mutual information between input (signal) and output (network's activity), and
is optimized by synaptic depression. Introducing correlations in signal
structure resulted in the decrease of input-output mutual information. Our
results suggest that in neural systems with plastic connectivity, information
is not merely carried passively by the signal; rather, the information content
of the signal itself might determine the mode of its processing by a local
neuronal circuit.Comment: 15 pages, 4 pages, in press for "Chaos
Reliability and Validity of The Finnish Version of The Boston Carpal Tunnel Questionnaire among Surgically Treated Carpal Tunnel Syndrome Patients
Background and Aims: The Boston Carpal Tunnel Questionnaire is the most commonly used outcome measure in the assessment of carpal tunnel syndrome. The purpose of this study was to translate the original Boston Carpal Tunnel Questionnaire into Finnish and validate its psychometric properties. Materials and Methods: We translated and culturally adapted the Boston Carpal Tunnel Questionnaire into Finnish. Subsequently, 193 patients completed the Finnish version of the Boston Carpal Tunnel Questionnaire, 6-Item CTS Symptoms Scale, and EuroQol 5 Dimensions 12 months after carpal tunnel release. The Boston Carpal Tunnel Questionnaire was re-administered after a 2-week interval. We calculated construct validity, internal consistency, test-retest reliability, and coefficient of repeatability. We also examined floor and ceiling effects. Results: The cross-cultural adaptation required only minor modifications to the questions. Both subscales of the Boston Carpal Tunnel Questionnaire (Symptom Severity Scale and Functional Status Scale) correlated significantly with the CTS-6 and EuroQol 5 Dimensions, indicating good construct validity. The Cronbach's alpha was 0.93 for both the Symptom Severity Scale and Functional Status Scale, indicating high internal consistency. Test-retest reliability was excellent, with an intraclass correlation coefficient greater than 0.8 for both scales. The coefficient of repeatability was 0.80 for the Symptom Severity Scale and 0.68 for the Functional Status Scale. We observed a floor effect in the Functional Status Scale in 28% of participants. Conclusion: Our study shows that the present Finnish version of the Boston Carpal Tunnel Questionnaire is reliable and valid for the evaluation of symptom severity and functional status among surgically treated carpal tunnel syndrome patients. However, owing to the floor effect, the Functional Status Score may have limited ability to detect differences in patients with good post-operative outcomes.Peer reviewe
Effect of neck strength training on health-related quality of life in females with chronic neck pain: a randomized controlled 1-year follow-up study
Abstract
Background
Chronic neck pain is a common condition associated not only with a decrease in neck muscle strength, but also with decrease in health-related quality of life (HRQoL). While neck strength training has been shown to be effective in improving neck muscle strength and reducing neck pain, HRQoL among patients with neck pain has been reported as an outcome in only two short-term exercise intervention studies. Thus, reports on the influence of a long-term neck strength training intervention on HRQoL among patients with chronic neck pain have been lacking. This study reports the effect of one-year neck strength training on HRQoL in females with chronic neck pain.
Methods
One hundred eighty female office workers, 25 to 53 years of age, with chronic neck pain were randomized to a strength training group (STG, n = 60), endurance training group (ETG, n = 60) or control group (CG, n = 60). The STG performed high-intensity isometric neck strengthening exercises with an elastic band while the ETG performed lighter dynamic neck muscle training. The CG received a single session of guidance on stretching exercises. HRQoL was assessed using the generic 15D questionnaire at baseline and after 12 months. Statistical comparisons among the groups were performed using bootstrap-type analysis of covariance (ANCOVA) with baseline values as covariates. Effect sizes were calculated using the Cohen method for paired samples.
Results
Training led to statistically significant improvement in the 15D total scores for both training groups, whereas no changes occurred for the control group (P = 0.012, between groups). The STG improved significantly in five of 15 dimensions, while the ETG improved significantly in two dimensions. Effect size (and 95% confidence intervals) for the 15D total score was 0.39 (0.13 to 0.72) for the STG, 0.37 (0.08 to 0.67) for the ETG, and -0.06 (-0.25 to 0.15) for the CG.
Conclusions
One year of either strength or endurance training seemed to moderately enhance the HRQoL. Neck and upper body training can be recommended to improve HRQoL of females with neck pain if they are motivated for long-term regular exercise.
Trial Registration
ClinicalTrials.gov NCT01057836peerReviewe
Chaotic Phase Synchronization in Bursting-neuron Models Driven by a Weak Periodic Force
We investigate the entrainment of a neuron model exhibiting a chaotic
spiking-bursting behavior in response to a weak periodic force. This model
exhibits two types of oscillations with different characteristic time scales,
namely, long and short time scales. Several types of phase synchronization are
observed, such as 1 : 1 phase locking between a single spike and one period of
the force and 1 : l phase locking between the period of slow oscillation
underlying bursts and l periods of the force. Moreover, spiking-bursting
oscillations with chaotic firing patterns can be synchronized with the periodic
force. Such a type of phase synchronization is detected from the position of a
set of points on a unit circle, which is determined by the phase of the
periodic force at each spiking time. We show that this detection method is
effective for a system with multiple time scales. Owing to the existence of
both the short and the long time scales, two characteristic phenomena are found
around the transition point to chaotic phase synchronization. One phenomenon
shows that the average time interval between successive phase slips exhibits a
power-law scaling against the driving force strength and that the scaling
exponent has an unsmooth dependence on the changes in the driving force
strength. The other phenomenon shows that Kuramoto's order parameter before the
transition exhibits stepwise behavior as a function of the driving force
strength, contrary to the smooth transition in a model with a single time
scale
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