1,355 research outputs found
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The international standards organization (ISO) 9000 series: A competitive pressure for U.S. business
ISO 9000 is becoming an increasingly significant issue for U. S. companies engaged in international business activity. Certification is fast becoming a requirement for companies doing business in Europe and other parts of the worl
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Evidence for clonal selection of gamma/delta T cells in response to a human pathogen.
T cells bearing gamma/delta antigen receptors comprise a resident population of intraepithelial lymphocytes in organs such as skin, gut, and lungs, where they are strategically located to contribute to the initial defense against infection. An important unsolved question about antigen-driven gamma/delta T cell responses regards the breadth of their T cell receptor (TCR) repertoire, since many specific epithelial compartments in mice display limited diversity. We have examined the diversity of TCR delta gene expression among human gamma/delta T cells from skin lesions induced by intradermal challenge with Mycobacterium leprae. We show that the vast majority of gamma/delta cells from M. leprae lesions use either V delta 1-J delta 1 or V delta 2-J delta 1 gene rearrangements and, within a given region of the lesion, display limited junctional diversity. This contrasts markedly with the extensive diversity of gamma/delta T cells from peripheral blood of these same individuals, as well as skin from normal donors. These results indicate that the gamma/delta response to M. leprae involves the selection of a limited number of clones from among a diverse repertoire, probably in response to specific mycobacterial and/or host antigens
Tree growth and management in Ugandan agroforestry systems: effects of root pruning on tree growth and crop yield
Tree root pruning is a potential tool for managing below-ground competition when trees and crops are grown together in agroforestry systems. This study investigates its effects on growth and root distribution of Alnus acuminata (HB & K), Casuarina equisetifolia (L), Grevillea robusta (A. Cunn. ex R. Br), Maesopsis eminii (Engl.), and Markhamia lutea (Benth.) K. Schum. and on yield of adjacent crops in sub-humid Uganda. The trees were 3 years old at the commencement of the study, and most species were competing strongly with crops. Tree roots were pruned 41 months after planting by cutting and back-filling a trench to a depth of 0.3 m, at a distance of 0.3 m from the trees, on one side of the tree row. The trench was re-opened and roots re-cut at 50 and 62 months after planting. Effects on tree growth and root distribution were assessed over a 3 year period, and crop yield after the third root pruning at 62 months is reported here. Overall, root pruning had only a slight effect on tree growth: height growth was unaffected and diameter growth was reduced by only 4 %. A substantial amount of root re-growth was observed by 11 months after pruning. Tree species varied in the number and distribution of their roots, and Casuarina and Markhamia had considerably more roots per unit of trunk volume than the other tree species, especially in the surface soil layers. Casuarina and Maesopsis were the most competitive tree species with crops and Grevillea and Markhamia the least. Crop yield data provides strong evidence of the redistribution of root activity following root pruning, so that competition increased on the unpruned side of tree rows. Thus, one-sided root pruning will only be of use to farmers in a few circumstances.
Key words: Alnus acuminata, Casuarina equisetifolia, Grevillea robusta, Maesopsis eminii, Markhamia lutea, root distribution, root functio
Likelihood of aneurysmal subarachnoid haemorrhage in patients with normal unenhanced CT, CSF xanthochromia on spectrophotometry and negative CT angiography
Peer reviewedPublisher PD
Presence and duration of reactivity to pedometers in adults
PURPOSE: To examine the presence and duration of reactivity to wearing a pedometer and
recording daily step counts in free-living adults.
METHODS: On the first visit to the laboratory 90 participants (69% female, age = 26.8±13.0 years,
BMI = 23.4±4.0 kg/m2), blinded to the study aim, were provided with a sealed pedometer (New
Lifestyles NL-800) and informed that it was a 'Body Posture Monitor' (covert condition).
Participants wore the pedometer throughout waking hours for 1 week. Upon return to the
laboratory, stored step counts were recorded and participants were informed that the device was
a pedometer. Participants wore the pedometer unsealed (no restriction on viewing the step count
display) for 2 weeks, during which they recorded their daily step count in a diary (diary
condition). Mean daily step counts recorded during the covert condition and during weeks 1 and
2 of the diary condition were compared using a repeated-measures ANOVA.
RESULTS: There was a significant overall effect of study condition (P<0.001), with post hoc
analyses revealing that mean daily step counts reported during the first week of the diary
condition (9898±3002 steps/day) were significantly higher than those reported during the covert
condition (8331±3010 steps/day) and during the second week of the diary condition (8226±3170
steps/day) (P<0.001).
CONCLUSION: Reactivity to wearing unsealed pedometers and step count recording appears to last
for 1 week. In the absence of any intervention material, step counts return to normal levels
during the second week of monitoring, and therefore represent a more accurate estimate of
habitual activity. These findings have important implications to both researchers and
practitioners interested in the use of pedometers for physical activity surveillance and promotion
Tomographic approach to resolving the distribution of LISA Galactic binaries
The space based gravitational wave detector LISA is expected to observe a
large population of Galactic white dwarf binaries whose collective signal is
likely to dominate instrumental noise at observational frequencies in the range
10^{-4} to 10^{-3} Hz. The motion of LISA modulates the signal of each binary
in both frequency and amplitude, the exact modulation depending on the source
direction and frequency. Starting with the observed response of one LISA
interferometer and assuming only doppler modulation due to the orbital motion
of LISA, we show how the distribution of the entire binary population in
frequency and sky position can be reconstructed using a tomographic approach.
The method is linear and the reconstruction of a delta function distribution,
corresponding to an isolated binary, yields a point spread function (psf). An
arbitrary distribution and its reconstruction are related via smoothing with
this psf. Exploratory results are reported demonstrating the recovery of binary
sources, in the presence of white Gaussian noise.Comment: 13 Pages and 9 figures high resolution figures can be obtains from
http://www.phys.utb.edu/~rajesh/lisa_tomography.pd
Improving Lunar Exploration with Robotic Follow-up
We are investigating how augmenting human field work with subsequent robot activity can improve lunar exploration. Robotic "follow-up" might involve: completing geology observations; making tedious or long-duration measurements of a target site or feature; curating samples in-situ; and performing unskilled, labor-intensive work. To study this technique, we have begun conducting a series of lunar analog field tests at Haughton Crater (Canada). Motivation: In most field geology studies on Earth, explorers often find themselves left with a set of observations they would have liked to make, or samples they would have liked to take, if only they had been able to stay longer in the field. For planetary field geology, we can imagine mobile robots - perhaps teleoperated vehicles previously used for manned exploration or dedicated planetary rovers - being deployed to perform such follow-up activities [1]
Daily step count of British military males with bilateral lower limb amputations: A comparison of in-patient rehabilitation with the consecutive leave period between admissions
© The International Society for Prosthetics and Orthotics 2018. Background: Reduced function and health in individuals with lower limb amputation is well documented. Step count measurement could facilitate rehabilitation and help monitor functional health outcomes. Objectives: To determine whether mean daily step count changed between in-patient rehabilitation and consecutive leave periods. Study Design: Observational study. Methods: Nine individuals with bilateral traumatic amputations attending rehabilitation at the Defence Medical Rehabilitation Centre during a 4-month period were invited to participate in the study (two bilateral transfemoral, two bilateral transfemoral/knee disarticulation, two transfemoral/transtibial, one bilateral transfemoral plus transradial, one bilateral transfemoral plus transhumeral and one transfemoral/transtibial/transradial). Prostheses worn by each participant were fitted with an activity monitor (LAM2 TM ; PAL Technologies Ltd, Glasgow). Mean daily step count was analysed for each participant following 2 weeks in-patient rehabilitation and consecutive 2 weeks away from rehabilitation. Results: Nine participants completed the study (time since injury: 19 ± 7 months, age: 26 ± 6 years). Mean daily step count significantly decreased from 2258 ± 192 during in-patient rehabilitation to 1387 ± 363 at home (p < 0.01). Conclusion: The step count decreased when away from rehabilitation, confirming the hypothesis that the mean daily step count would change between in-patient rehabilitation and consecutive leave period. Clinical relevance: These data provide an indication of the step count achievable by young, military male personnel with bilateral lower limb amputations and highlights differences between intensive in-patient rehabilitation and consecutive leave periods. It is suggested that further investigation and support of clinical monitoring could facilitate rehabilitation tailored to the individual
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