362 research outputs found
Cost-Utility Analysis of Venous Thromboembolism Prophylaxis Strategies for People Undergoing Elective Total Hip and Total Knee Replacement Surgeries in the English National Health Service
Background: Major orthopedic surgery, such as elective total hip replacement (eTHR) and elective total knee replacement (eTKR), are associated with a higher risk of venous thromboembolism (VTE) than other surgical procedures. Little is known, however, about the cost-effectiveness of VTE prophylaxis strategies in people undergoing these procedures. Aim: The aim of this work was to assess the cost-effectiveness of these strategies from the English National Health Service perspective to inform NICE guideline (NG89) recommendations. Materials and Methods: Cost-utility analysis, using decision modeling, was undertaken to compare 15 VTE prophylaxis strategies for eTHR and 12 for eTKR, in addition to “no prophylaxis” strategy. The analysis complied with the NICE Reference Case. Structure and assumptions were agreed with the guideline committee. Incremental net monetary benefit (INMB) was calculated, vs. the model comparator (LMWH+ antiembolism stockings), at a threshold of £20,000/quality-adjusted life-year (QALY) gained. The model was run probabilistically. Deterministic sensitivity analyses (SAs) were undertaken to assess the robustness of the results. Results: The most cost-effective strategies were LMWH for 10 days followed by aspirin for 28 days (INMB = £530 [95% CI: -£784 to £1,103], probability of being most cost-effective = 72%) for eTHR, and foot pump (INMB = £353 [95% CI: -£101 to £665]; probability of being most cost-effective = 18%) for eTKR. There was considerable uncertainty regarding the cost-effectiveness ranking in the eTKR analysis. The results were robust to change in all SAs. Conclusions: For eTHR, LMWH (standard dose) for 10 days followed by aspirin for 28 days is the most cost-effective VTE prophylaxis strategy. For eTKR, the results are highly uncertain but foot pump appeared to be the most cost-effective strategy, followed closely by aspirin (low dose). Future research should focus on assessing cost-effectiveness of VTE prophylaxis in the eTKR population.Peer reviewe
Clues to the nature of the Delta^*(1700) resonance from pion- and photon-induced reactions
We make a study of the (pi^- p --> K^0 pi^0 Lambda), (pi^+ p --> K^+ pi^+
Lambda), (K^+\bar{K}^0 p), (K^+ pi^+ Sigma^0), (K^+ pi^0 Sigma^+), and (eta
pi^+ p) reactions, in which the basic dynamics is given by the excitation of
the Delta^*(1700) resonance which subsequently decays into (K Sigma^*(1385)) or
(Delta(1232) eta). In a similar way we also study the (gamma p --> K^0 pi^+
Lambda), (K^+ pi^- Sigma^+), (K^+ pi^+ Sigma^-), (K^0 pi^0 Sigma^+), and (eta
pi^0 p) related reactions. The cross sections are proportional to the square of
the coupling of Delta^*(1700) to (Sigma^*K), (Delta eta) for which there is no
experimental information but which is provided in the context of coupled
channels chiral unitary theory where the Delta^*(1700) is dynamically
generated. Within present theoretical and experimental uncertainties one can
claim a global qualitative agreement between theory and experiment. We provide
a list of items which need to be improved in order to make further progress
along these lines.Comment: 11 pages, 5 figure
Atomistic spin textures on-demand in the van der Waals layered magnet CrSBr
Controlling magnetism in low dimensional materials is essential for designing
devices that have feature sizes comparable to several critical length scales
that exploit functional spin textures, allowing the realization of low-power
spintronic and magneto-electric hardware. [1] Unlike conventional
covalently-bonded bulk materials, van der Waals (vdW)-bonded layered magnets
[2-4] offer exceptional degrees of freedom for engineering spin textures. [5]
However, their structural instability has hindered microscopic studies and
manipulations. Here, we demonstrate nanoscale structural control in the layered
magnet CrSBr creating novel spin textures down to the atomic scale. We show
that it is possible to drive a local structural phase transformation using an
electron beam that locally exchanges the bondings in different directions,
effectively creating regions that have vertical vdW layers embedded within the
horizontally vdW bonded exfoliated flakes. We calculate that the newly formed
2D structure is ferromagnetically ordered in-plane with an energy gap in the
visible spectrum, and weak antiferromagnetism between the planes. Our study
lays the groundwork for designing and studying novel spin textures and related
quantum magnetic phases down to single-atom sensitivity, potentially to create
on-demand spin Hamiltonians probing fundamental concepts in physics, [6-10] and
for realizing high-performance spintronic, magneto-electric and topological
devices with nanometer feature sizes. [11,12]Comment: Main manuscript: 11 pages, 4 figures ; Extended data: 22 pages, 19
figure
Photo- and Electron-Production of Mesons on Nucleons and Nuclei
In these lectures I will show some results obtained with the chiral unitary
approach applied to the photo and electroproduction of mesons. The results for
photoproduction of and , together with
related reactions will be shown, having with common denominator the excitation
of the resonance which is one of those dynamically generated in
the chiral unitary approach. Then I will show results obtained for the reaction which reproduce the bulk of the data except for a
pronounced peak, giving support to a new mesonic resonance, X(2175). Results
will also be shown for the electromagnetic form factors of the
resonance, also dynamically generated in this approach. Finally, I will show
some results on the photoproduction of the in nuclei, showing that
present experimental results claiming a shift of the mass in the
medium are tied to a particular choice of background and are not conclusive.
One the other hand, the same experimental results show unambiguously a huge
increase of the width in the nuclear medium.Comment: Lecture at the "International School of Nuclear Physics", 29th Course
Quarks in Hadrons and Nuclei, Erice, Italy, September 2007. Note added in
Proofs concerning the mixed events technique and other comments on omega
productio
Does cultural integration explain a mental health advantage for adolescents?
BACKGROUND: A mental health advantage has been observed among adolescents in urban areas. This prospective study tests whether cultural integration measured by cross-cultural friendships explains a mental health advantage for adolescents. METHODS: A prospective cohort of adolescents was recruited from 51 secondary schools in 10 London boroughs. Cultural identity was assessed by friendship choices within and across ethnic groups. Cultural integration is one of four categories of cultural identity. Using gender-specific linear-mixed models we tested whether cultural integration explained a mental health advantage, and whether gender and age were influential. Demographic and other relevant factors, such as ethnic group, socio-economic status, family structure, parenting styles and perceived racism were also measured and entered into the models. Mental health was measured by the Strengths and Difficulties Questionnaire as a 'total difficulties score' and by classification as a 'probable clinical case'. RESULTS: A total of 6643 pupils in first and second years of secondary school (ages 11-13 years) took part in the baseline survey (2003/04) and 4785 took part in the follow-up survey in 2005-06. Overall mental health improved with age, more so in male rather than female students. Cultural integration (friendships with own and other ethnic groups) was associated with the lowest levels of mental health problems especially among male students. This effect was sustained irrespective of age, ethnicity and other potential explanatory variables. There was a mental health advantage among specific ethnic groups: Black Caribbean and Black African male students (Nigerian/Ghanaian origin) and female Indian students. This was not fully explained by cultural integration, although cultural integration was independently associated with better mental health. CONCLUSIONS: Cultural integration was associated with better mental health, independent of the mental health advantage found among specific ethnic groups: Black Caribbean and some Black African male students and female Indian students
One‐dimensional patterning of cells in silicone wells via compression‐induced fracture
We have adapted our existing compression‐induced fracture technology to cell culture studies by generating linear patterns on a complex cell culture well structure rather than on simple solid constructs. We present a simple method to create one‐dimensional (1D), submicron, and linear patterns of extracellular matrix on a multilayer silicone material. We identified critical design parameters necessary to optimize compression‐induced fracture patterning on the wells, and applied stresses using compression Hoffman clamps. Finite‐element analyses show that the incorporation of the well improves stress homogeneity (stress variation = 25%), and, thus, crack uniformity over the patterned region. Notably, a shallow well with a thick base (vs. deeper wells with thinner bases) reduces out‐of‐plane deflections by greater than a sixth in the cell culture region, improving clarity for optical imaging. The comparison of cellular and nuclear shape indices of a neuroblast line cultured on patterned 1D lines and unpatterned 2D surfaces reveals significant differences in cellular morphology, which could impact many cellular functions. Because 1D cell cultures recapitulate many important phenotypical traits of 3D cell cultures, our culture system offers a simple means to further study the relationship between 1D and 3D cell culture environments, without demanding expensive engineering techniques and expertise. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1361–1369, 2014.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106690/1/jbma34814.pd
QUEST: A New Frontiers Uranus Orbiter Mission Concept Study
The ice giant planets, Uranus and Neptune, are fundamentally different from the gas giant and terrestrial planets. Though ice giants represent the most common size of exoplanet and possess characteristics that challenge our understanding of the way our solar system formed and evolved, they remain the only class of planetary object without a dedicated spacecraft mission. The inclusion of a Uranus orbiter as the third highest priority Flagship mission in the NASA Planetary Science Decadal Survey “Vision and Voyages for Planetary Science in the Decade 2013–2022” indicates a high level of support for exploration of the ice giants by the planetary science community. However, given the substantial costs associated with a flagship mission, it is critical to explore lower cost options if we intend to visit Uranus within an ideal launch window of 2029 - 2034 when a Jupiter gravity assist becomes available. In this paper, we describe the Quest to Uranus to Explore Solar System Theories (QUEST), a New Frontiers class Uranus orbiter mission concept study performed at the 30th Annual NASA/JPL Planetary Science Summer Seminar. The proposed QUEST platform is a spin-stabilized spacecraft designed to undergo highly elliptical, polar orbits around Uranus during a notional one-year primary science mission. The proposed major science goals of the mission are (1) to use Uranus as a natural laboratory to better understand the dynamos that drive magnetospheres in the solar system and beyond and (2) to identify the energy transport mechanisms in Uranus' magnetic, atmospheric, and interior environments in contrast with the other giant planets. With substantial mass, power, and cost margins, this mission concept demonstrates a compelling, feasible option for a New Frontiers Uranus orbiter mission
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