8,733 research outputs found
Finite-size scaling in complex networks
A finite-size-scaling (FSS) theory is proposed for various models in complex
networks. In particular, we focus on the FSS exponent, which plays a crucial
role in analyzing numerical data for finite-size systems. Based on the
droplet-excitation (hyperscaling) argument, we conjecture the values of the FSS
exponents for the Ising model, the susceptible-infected-susceptible model, and
the contact process, all of which are confirmed reasonably well in numerical
simulations
Treatment regimens for rifampicin-resistant tuberculosis: highlighting a research gap
Treatment guidance for non-multidrug-resistant (MDR) rifampicin-resistant (RMP-R) tuberculosis (TB) is variable. We aimed to undertake a systematic review and meta-analysis of the randomised controlled trial (RCT) data behind such guidelines to identify the most efficacious treatment regimens. Ovid MEDLINE, the Web of Science and EMBASE were mined using search terms for TB, drug therapy and RCTs. Despite 12 604 records being retrieved, only three studies reported treatment outcomes by regimen for patients with non-MDR RMP-R disease, preventing meta-analysis. Our systematic review highlights a substantial gap in the literature regarding evidence-based treatment regimens for RMP-R TB
Smoothening Transition of a Two-Dimensional Pressurized Polymer Ring
We revisit the problem of a two-dimensional polymer ring subject to an
inflating pressure differential. The ring is modeled as a freely jointed closed
chain of N monomers. Using a Flory argument, mean-field calculation and Monte
Carlo simulations, we show that at a critical pressure, , the
ring undergoes a second-order phase transition from a crumpled, random-walk
state, where its mean area scales as , to a smooth state with
. The transition belongs to the mean-field universality class. At
the critical point a new state of polymer statistics is found, in which
. For we use a transfer-matrix calculation to derive
exact expressions for the properties of the smooth state.Comment: 9 pages, 8 figure
A time-duration measure of continuity of care to optimise utilisation of primary health care: A threshold effects approach among people with diabetes
© 2019 The Author(s). Background: Literature highlighted the importance of timely access and ongoing care provided at primary care settings in reducing hospitalisation and health care resource uses. However, the effect of timely access to primary care has not been fully captured in most of the current continuity of care indices. This study aimed to develop a time-duration measure of continuity of primary care ("cover index") capturing the proportion of time an individual is under the potentially protective effect of primary health care contacts. Methods: An observational study was conducted on 36,667 individuals aged 45 years or older with diabetes mellitus extracted from Western Australian linked administrative data. Threshold effect models were used to determine the maximum time interval between general practitioner (GP) visits that afforded a protective effect against avoidable hospitalisation across complication cohorts. The optimal maximum time interval was used to compute a cover index for each individual. The cover was evaluated using descriptive statistics stratified by population socio-demographic characteristics. Results: The optimal maximum time between GP visits was 9-13 months for people with diabetes with no complication, 5-11 months for people with diabetes with 1-2 complications, and 4-9 months for people with diabetes with 3+ complications. The cover index was lowest among those aged 75+ years, males, Indigenous people, socio-economically disadvantaged and those in very remote areas. Conclusions: This study developed a new measure of continuity of primary care that adds a time parameter to capturing longitudinal continuity. Cover has the potential to better capture underuse of primary care and will significantly contribute to the sparsely available methods for analysis of linked administrative data in evaluating continuity of care for people with chronic conditions
Solid state NMR and X-ray diffraction studies of α-d-galacturonic acid monohydrate
Crystalline a-d-galacturonic acid monohydrate has been studied by 13C CPMAS NMR and X-ray crystallography. The molecular dynamics were investigated by evaluating 13C spin-lattice relaxation in the rotating frame (T1?) and chemical-shift-anisotropy properties of each carbon. Only limited molecular motions can be detected in the low frequency
Spitzer Observations of Interstellar Object 1I/`Oumuamua
1I/`Oumuamua is the first confirmed interstellar body in our Solar System.
Here we report on observations of `Oumuamua made with the Spitzer Space
Telescope on 2017 November 21--22 (UT). We integrated for 30.2~hours at 4.5
micron (IRAC channel 2). We did not detect the object and place an upper limit
on the flux of 0.3 uJy (3sigma). This implies an effective spherical diameter
less than [98, 140, 440] meters and albedo greater than [0.2, 0.1, 0.01] under
the assumption of low, middle, or high thermal beaming parameter eta,
respectively. With an aspect ratio for `Oumuamua of 6:1, these results
correspond to dimensions of [240:40, 341:57, 1080:180] meters, respectively. We
place upper limits on the amount of dust, CO, and CO2 coming from this object
that are lower than previous results; we are unable to constrain the production
of other gas species. Both our size and outgassing limits are important because
`Oumuamua's trajectory shows non-gravitational accelerations that are sensitive
to size and mass and presumably caused by gas emission. We suggest that
`Oumuamua may have experienced low-level post-perihelion volatile emission that
produced a fresh, bright, icy mantle. This model is consistent with the
expected eta value and implied high albedo value for this solution, but, given
our strict limits on CO and CO2, requires another gas species --- probably H2O
--- to explain the observed non-gravitational acceleration. Our results extend
the mystery of `Oumuamua's origin and evolution
Consumption of rice, acceptability and sensory qualities of fortified rice amongst consumers of social safety net rice in Nepal
INTRODUCTION: Micronutrient deficiencies are prevalent in Nepal where starchy foods constitute a large proportion of diets and consumption of micronutrient-rich foods is inadequate. We conducted a study to determine whether rice would be an appropriate vehicle for micronutrient fortification in Nepal. MATERIALS AND METHODS: In Bajura in remote rural Nepal, we conducted a household survey to characterize rice intakes in 195 households, and a double-blinded acceptability test with 177 social safety net rice consumers ≥18 years of age. Of these, 168 tasted fortified and unfortified rice to assess whether respondents could differentiate between fortified and non-fortified rice and their sensory properties. Rice was fortified by blending hot extruded kernels containing 6 micronutrients together with non-fortified rice at a 1:99 ratio. We used binomial tests to assess whether participants could correctly differentiate fortified rice, from non-fortified rice and paired t-tests to compare scores for sensory qualities of cooked fortified and non-fortified rice. We used multiple regression to test associations between per capita consumption and age, gender, wealth and food security. RESULTS: Per capita consumption of rice (median 216g/day, IQR 144.0, 288.0) did not vary by wealth but was +52.08g, (95% CI 10.43, 93.72) higher amongst moderately to severely food insecure households compared with food secure / mildly food insecure. Most respondents could not differentiate fortified rice from non-fortified rice: 37.5% identified uncooked fortified rice and 39.3% cooked rice, which was not different from the 33% expected by chance (p = 0.22 and p = 0.09 respectively). The sensory qualities of fortified rice were acceptable (scoring 3.9 out of 5) and did not differ from non-fortified rice (p>0.05). CONCLUSION: A rice fortification programme implemented through the Nepal Food Corporation's social safety nets has potential because purchase and consumption of rice is high and fortified rice is acceptable among consumers in remote food insecure areas of Nepal
The regional economic impact of more graduates in the labour market: a “micro-to-macro” analysis for Scotland
This paper explores the system-wide impact of graduates on the regional economy. Graduates enjoy a significant wage premium, often interpreted as reflecting their greater productivity relative to non-graduates. If this is so there is a clear and direct supply-side impact of HEI activities on regional economies. We use an HEI-disaggregated computable general equilibrium model of Scotland to estimate the impact of the growing proportion of graduates in the Scottish labour force that is implied by the current participation rate and demographic change, taking the graduate wage premium in Scotland as an indicator of productivity enhancement. While the detailed results vary with alternative assumptions about the extent to which wage premia reflect productivity, they do suggest that the long-term supply-side impacts of HEIs provide a significant boost to regional GDP. Furthermore, the results suggest that the supply-side impacts of HEIs are likely to be more important than the expenditure impacts that are the focus of most HEI impact studies
The effect of beta-alanine supplementation on neuromuscular fatigue in elderly (55–92 Years): a double-blind randomized study
<p>Abstract</p> <p>Background</p> <p>Ageing is associated with a significant reduction in skeletal muscle carnosine which has been linked with a reduction in the buffering capacity of muscle and in theory, may increase the rate of fatigue during exercise. Supplementing beta-alanine has been shown to significantly increase skeletal muscle carnosine. The purpose of this study, therefore, was to examine the effects of ninety days of beta-alanine supplementation on the physical working capacity at the fatigue threshold (PWC<sub>FT</sub>) in elderly men and women.</p> <p>Methods</p> <p>Using a double-blind placebo controlled design, twenty-six men (n = 9) and women (n = 17) (age ± SD = 72.8 ± 11.1 yrs) were randomly assigned to either beta-alanine (BA: 800 mg × 3 per day; n = 12; CarnoSyn™) or Placebo (PL; n = 14) group. Before (pre) and after (post) the supplementation period, participants performed a discontinuous cycle ergometry test to determine the PWC<sub>FT</sub>.</p> <p>Results</p> <p>Significant increases in PWC<sub>FT </sub>(28.6%) from pre- to post-supplementation were found for the BA treatment group (p < 0.05), but no change was observed with PL treatment. These findings suggest that ninety days of BA supplementation may increase physical working capacity by delaying the onset of neuromuscular fatigue in elderly men and women.</p> <p>Conclusion</p> <p>We suggest that BA supplementation, by improving intracellular pH control, improves muscle endurance in the elderly. This, we believe, could have importance in the prevention of falls, and the maintenance of health and independent living in elderly men and women.</p
Improving 3D ultrasound prostate localisation in radiotherapy through increased automation of interfraction matching.
Background and purpose Daily image guidance is standard care for prostate radiotherapy. Innovations which improve the accuracy and efficiency of ultrasound guidance are needed, particularly with respect to reducing interobserver variation. This study explores automation tools for this purpose, demonstrated on the Elekta Clarity Autoscan®. The study was conducted as part of the Clarity-Pro trial (NCT02388308). Materials and methods Ultrasound scan volumes were collected from 32 patients. Prostate matches were performed using two proposed workflows and the results compared with Clarity's proprietary software. Gold standard matches derived from manually localised landmarks provided a reference. The two workflows incorporated a custom 3D image registration algorithm, which was benchmarked against a third-party application (Elastix). Results Significant reductions in match errors were reported from both workflows compared to standard protocol. Median (IQR) absolute errors in the left-right, anteroposterior and craniocaudal axes were lowest for the Manually Initiated workflow: 0.7(1.0) mm, 0.7(0.9) mm, 0.6(0.9) mm compared to 1.0(1.7) mm, 0.9(1.4) mm, 0.9(1.2) mm for Clarity. Median interobserver variation was ≪0.01 mm in all axes for both workflows compared to 2.2 mm, 1.7 mm, 1.5 mm for Clarity in left-right, anteroposterior and craniocaudal axes. Mean matching times was also reduced to 43 s from 152 s for Clarity. Inexperienced users of the proposed workflows attained better match precision than experienced users on Clarity. Conclusion Automated image registration with effective input and verification steps should increase the efficacy of interfraction ultrasound guidance compared to the current commercially available tools
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