1,255 research outputs found
A new in-situ method to estimate fish target strength reveals high variability in broadband measurements
Acknowledgements The authors thank the Greenland Institute of Natural Resources (GINR), the University of Aberdeen, and Marine Alliance for Science and Technology for Scotland (MASTS) for funding this study. MASTS is funded by the Scottish Funding Council (grant no. HR09011) and contributing institutions. Further, they thank GINR for providing access to their facilities.Peer reviewedPublisher PD
Actively stabilized wavelength-insensitive carrier elimination from an electro-optically modulated laser beam
We demonstrate a simple and robust technique for removal of the carrier wave
from a phase-modulated laser beam, using a non-interferometric method that is
insensitive to the modulation frequency and instead exploits the
polarization-dependence of electro-optic modulation. An actively stabilized
system using feedback via a liquid crystal cell yields long-term carrier
suppression in excess of 28 dB at the expense of a 6.5 dB reduction in sideband
power.Comment: 9 pages, 5 figure
The emotional context of self-management in chronic illness: a qualitative study of the role of health professionals support in the self-management of type 2 diabetes
© 2008 Furler et al; licensee BioMed Central Ltd.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background
Support for patient self-management is an accepted role for health professionals. Little evidence exists on the appropriate basis for the role of health professionals in achieving optimum self-management outcomes. This study explores the perceptions of people with type 2 diabetes about their self-management strategies and how relationships with health professionals may support this.
Methods
Four focus groups were conducted with people with type 2 diabetes: two with English-speaking and one each with Turkish and Arabic-speaking. Transcripts from the groups were analysed drawing on grounded hermeneutics and interpretive description.
Results
We describe three conceptually linked categories of text from the focus groups based on emotional context of self management, dominant approaches to self management and support from health professionals for self management. All groups described important emotional contexts to living with and self-managing diabetes and these linked closely with how they approached their diabetes management and what they looked for from health professionals. Culture seemed an important influence in shaping these linkages.
Conclusion
Our findings suggest people construct their own individual self-management and self-care program, springing from an important emotional base. This is shaped in part by culture and in turn determines the aims each person has in pursuing self-management strategies and the role they make available to health professionals to support them. While health professionals' support for self-care strategies will be more congruent with patients' expectations if they explore each person's social, emotional and cultural circumstances, pursuit of improved health outcomes may involve a careful balance between supporting as well as helping shift the emotional constructs surrounding a patient life with diabetes
Emittance compensation with dynamically optimized photoelectron beam profiles
Much of the theory and experimentation concerning creation of a high-brightness electron beam from a photocathode, and then applying emittance compensation techniques, assumes that one must strive for a uniform density electron beam, having a cylindrical shape. On the other hand, this shape has large nonlinearities in the space-charge field profiles near the beam's longitudinal extrema. These nonlinearities are known to produce both transverse and longitudinal emittance growth. On the other hand, it has recently been shown by Luiten that by illuminating the cathode with an ultra-short laser pulse of appropriate transverse profile, a uniform density, ellipsoidally shaped bunch is dynamically formed, which then has linear space-charge fields in all dimensions inside of the bunch. We study here this process, and its marriage to the standard emittance compensation scenario that is implemented in most recent photoinjectors. It is seen that the two processes are compatible, with simulations indicating a very high brightness beam can be obtained. The robustness of this scheme to systematic errors is examined. Prospects for experimental tests of this scheme are discussed
The cost of reducing starting RNA quantity for Illumina BeadArrays: a bead-level dilution experiment.
BACKGROUND: The demands of microarray expression technologies for quantities of RNA place a limit on the questions they can address. As a consequence, the RNA requirements have reduced over time as technologies have improved. In this paper we investigate the costs of reducing the starting quantity of RNA for the Illumina BeadArray platform. This we do via a dilution data set generated from two reference RNA sources that have become the standard for investigations into microarray and sequencing technologies. RESULTS: We find that the starting quantity of RNA has an effect on observed intensities despite the fact that the quantity of cRNA being hybridized remains constant. We see a loss of sensitivity when using lower quantities of RNA, but no great rise in the false positive rate. Even with 10 ng of starting RNA, the positive results are reliable although many differentially expressed genes are missed. We see that there is some scope for combining data from samples that have contributed differing quantities of RNA, but note also that sample sizes should increase to compensate for the loss of signal-to-noise when using low quantities of starting RNA. CONCLUSIONS: The BeadArray platform maintains a low false discovery rate even when small amounts of starting RNA are used. In contrast, the sensitivity of the platform drops off noticeably over the same range. Thus, those conducting experiments should not opt for low quantities of starting RNA without consideration of the costs of doing so. The implications for experimental design, and the integration of data from different starting quantities, are complex.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Changes in Shoulder Pain and Disability After Thrust Manipulation in Subjects Presenting With Second and Third Rib Syndrome
AbstractObjectiveThe purpose of this preliminary study was to investigate changes in shoulder pain, disability, and perceived level of recovery after 2 sessions of upper thoracic and upper rib high-velocity low-amplitude (HVLA) thrust manipulation in patients with shoulder pain secondary to second and third rib syndrome.MethodsThis exploratory study evaluated 10 consecutive individuals with shoulder pain, with or without brachial pain, and a negative Neer impingement test, who completed the Shoulder Pain and Disability Index (SPADI), the numeric pain rating scale (NPRS), and the global rating of change. Patients received 2 sessions of HVLA thrust manipulation targeting the upper thoracic spine bilaterally and the second and third ribs on the symptomatic side. Outcome measures were completed after the first treatment session, at 48 hours, 1 month, and 3 months.ResultsPatients showed a significant decrease in SPADI (F = 59.997; P = .001) and significant decrease in resting shoulder NPRS (F = 63.439; P = .001). For both NPRS and SPADI, there were significant differences between the pretreatment scores and each of the postintervention scores through 3-month follow-up (P < .05). Large within-group effect sizes (Cohen's d ≥ 0.8) were found between preintervention data and all postintervention assessments in both outcomes. Mean global rating of change scores (+6.8 at 3 months) indicated "a very great deal better" outcome at long-term follow-up.ConclusionThis group of patients with shoulder pain secondary to second and third rib syndrome who received upper thoracic and upper rib HVLA thrust manipulations showed significant reductions in pain and disability and improvement in perceived level of recovery
Efficient Algorithm for Two-Center Coulomb and Exchange Integrals of Electronic Prolate Spheroidal Orbitals
We present a fast algorithm to calculate Coulomb/exchange integrals of
prolate spheroidal electronic orbitals, which are the exact solutions of the
single-electron, two-center Schr\"odinger equation for diatomic molecules. Our
approach employs Neumann's expansion of the Coulomb repulsion 1/|x-y|, solves
the resulting integrals symbolically in closed form and subsequently performs a
numeric Taylor expansion for efficiency. Thanks to the general form of the
integrals, the obtained coefficients are independent of the particular
wavefunctions and can thus be reused later.
Key features of our algorithm include complete avoidance of numeric
integration, drafting of the individual steps as fast matrix operations and
high accuracy due to the exponential convergence of the expansions.
Application to the diatomic molecules O2 and CO exemplifies the developed
methods, which can be relevant for a quantitative understanding of chemical
bonds in general.Comment: 27 pages, 9 figure
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