1,752 research outputs found
Application of Topological Operators over Data from InterCriteria Analysis
In this paper, two topological operators T and U over intuitionistic fuzzy sets are considered and applied. As a case study a parameter identification problem of E. coli fed-batch cultivation process model using genetic algorithms is investigated. A new result regarding T and U is established. The results obtained by the application of the topological operators over data processed by InterCriteria Analysis are discussed
Glutathione accelerates sodium channel inactivation in excised rat axonal membrane patches
The effects of glutathione were studied on the gating behaviour of sodium channels in membrane patches of rat axons. Depolarizing pulses from –120 to –40 mV elicited sodium currents of up to 500 pA, indicating the simultaneous activation of up to 250 sodium channels. Inactivation of these channels in the excised, inside-out configuration was fitted by two time constants ( h1=0.81 ms; h2= 5.03 ms) and open time histograms at 0 mV revealed a biexponential distribution of channel openings ( short=0.28 ms; long=3.68 ms). Both, the slow time constant of inactivation and the long lasting single channel openings disappeared after addition of the reducing agent glutathione (2–5 mM) to the bathing solution. Sodium channels of excised patches with glutathione present on the cytoplasmatic face of the membrane had inactivation kinetics similar to channels recorded in the cell-attached configuration. These observations indicate that redox processes may contribute to the gating of axonal sodium channels
Mortality of patients with multiple sclerosis: a cohort study in UK primary care
We aimed to estimate rates, causes and risk factors of all-cause mortality in a large population-based cohort of multiple sclerosis (MS) patients compared with patients without MS. Using data from the UK General Practice Research Database, we identified MS cases diagnosed during 2001–2006 and validated using patients’ original records where possible. We also included MS cases during 1993–2000 identified and validated in an earlier study. Cases were matched to up to ten referents without MS by age, sex, index date (date of first MS diagnosis for cases and equivalent reference date for controls), general practice and length of medical history before first MS diagnosis. Patients were followed up to identify deaths; hazard ratios (HRs) and 95 % confidence intervals (CIs) were estimated using Cox-proportional regression. MS patients (N = 1,822) had a significantly increased risk of all-cause mortality compared with referents (N = 18,211); adjusted HR 1.7 (95 % CI 1.4–2.1). Compared with referents, female MS patients had a higher but not significantly different HR for death than males; adjusted HR 1.86 (95 % CI 1.46–2.38) vs. HR 1.31 (95 % CI 0.93–1.84), respectively. The most commonly recorded cause of death in MS patients was ‘MS’ (41 %), with a higher proportion recorded among younger patients. A significantly higher proportion of referents than MS patients had cancer recorded as cause of death (40 vs. 19 %). Patients with MS have a significant 1.7-fold increased risk of all-cause mortality compared with the general population. MS is the most commonly recorded cause of death among MS patients. Electronic supplementary material The online version of this article (doi:10.1007/s00415-014-7370-3) contains supplementary material, which is available to authorized users
What is Asset-Based Community Development and how might it improve the health of people with long-term conditions? A realist synthesis
Abstract Background Asset Based Community Development (ABCD) appears to be a promising way to supporting people with long-term health problems but there is currently a lack of evidence to support this approach. Methods Taking a realist approach, a review and concept-mapping exercise of ABCD approaches to improve health were conducted with a view to providing a better understanding about these approaches, how they work, and who they work for. Results 29 papers were deemed relevant and included in the review. The realist synthesis and concept mapping helped identify concepts most commonly associated with ABCD but found no papers focussed on LTCs and thus no evidence that this approach improves health outcomes for people with LTCs. Conclusions Whilst there is a lack of clarity about how to implement ABCD or how to evaluate it, this paper offers a clearer theoretical framework about the essential ingredients needed to activate ABCD
Section on Prospects for Dark Matter Detection of the White Paper on the Status and Future of Ground-Based TeV Gamma-Ray Astronomy
This is a report on the findings of the dark matter science working group for
the white paper on the status and future of TeV gamma-ray astronomy. The white
paper was commissioned by the American Physical Society, and the full white
paper can be found on astro-ph (arXiv:0810.0444). This detailed section
discusses the prospects for dark matter detection with future gamma-ray
experiments, and the complementarity of gamma-ray measurements with other
indirect, direct or accelerator-based searches. We conclude that any
comprehensive search for dark matter should include gamma-ray observations,
both to identify the dark matter particle (through the charac- teristics of the
gamma-ray spectrum) and to measure the distribution of dark matter in galactic
halos.Comment: Report from the Dark Matter Science Working group of the APS
commissioned White paper on ground-based TeV gamma ray astronomy (19 pages, 9
figures
Detection of the hydroperoxyl radical HO2 toward \rho Oph A: Additional constraints on the water chemical network
Context: Hydrogen peroxide (HOOH) was recently detected toward \rho Oph A.
Subsequent astrochemical modeling that included reactions in the gas phase and
on the surface of dust grains was able to explain the observed abundance, and
highlighted the importance of grain chemistry in the formation of HOOH as an
intermediate product in water formation. This study also predicted that the
hydroperoxyl radical HO2, the precursor of HOOH, should be detectable. Aims: We
aim at detecting the hydroperoxyl radical HO2 in \rho Oph A. Methods: We used
the IRAM 30m and the APEX telescopes to target the brightest HO2 lines at about
130 and 260 GHz. Results: We detect five lines of HO2 (comprising seven
individual molecular transitions). The fractional abundance of HO2 is found to
be about 1e-10, a value similar to the abundance of HOOH. This observational
result is consistent with the prediction of the above mentioned astrochemical
model, and thereby validates our current understanding of the water formation
on dust grains. Conclusions: This detection, anticipated by a sophisticated
gas-grain chemical model, demonstrates that models of grain chemistry have
improved tremendously and that grain surface reactions now form a crucial part
of the overall astrochemical network.Comment: 5 pages, 4 figures, accepted for publication as a Letter to the
Editor in Astronomy and Astrophysic
Aligning everyday life priorities with people's self-management support networks: an exploration of the work and implementation of a needs-led telephone support system
Background: Recent initiatives to target the personal, social and clinical needs of people with long-term health conditions have had limited impact within primary care. Evidence of the importance of social networks to support people with long-term conditions points to the need for self-management approaches which align personal circumstances with valued activities. The Patient-Led Assessment for Network Support (PLANS) intervention is a needs-led assessment for patients to prioritise their health and social needs and provide access to local community services and activities. Exploring the work and practices of patients and telephone workers are important for understanding and evaluating the workability and implementation of new interventions.
Methods: Qualitative methods (interviews, focus group, observations) were used to explore the experience of PLANS from the perspectives of participants and the telephone support workers who delivered it (as part of an RCT) and the reasons why the intervention worked or not. Normalisation Process Theory (NPT) was used as a sensitising tool to evaluate: the relevance of PLANS to patients (coherence); the processes of engagement (cognitive participation); the work done for PLANS to happen (collective action); the perceived benefits and costs of PLANS (reflexive monitoring). 20 patients in the intervention arm of a clinical trial were interviewed and their telephone support calls were recorded and a focus group with 3 telephone support workers was conducted.
Results: Analysis of the interviews, support calls and focus group identified three themes in relation to the delivery and experience of PLANS. These are: formulation of ‘health’ in the context of everyday life; trajectories and tipping points: disrupting everyday routines; precarious trust in networks. The relevance of these themes are considered using NPT constructs in terms of the work that is entailed in engaging with PLANS, taking action, and who is implicated this process.
Conclusions: PLANS gives scope to align long-term condition management to everyday life priorities and valued aspects of life. This approach can improve engagement with health-relevant practices by situating them within everyday contexts. This has potential to increase utilisation of local resources with potential cost-saving benefits for the NH
Detection of interstellar hydrogen peroxide
The molecular species hydrogen peroxide, HOOH, is likely to be a key
ingredient in the oxygen and water chemistry in the interstellar medium. Our
aim with this investigation is to determine how abundant HOOH is in the cloud
core {\rho} Oph A. By observing several transitions of HOOH in the
(sub)millimeter regime we seek to identify the molecule and also to determine
the excitation conditions through a multilevel excitation analysis. We have
detected three spectral lines toward the SM1 position of {\rho} Oph A at
velocity-corrected frequencies that coincide very closely with those measured
from laboratory spectroscopy of HOOH. A fourth line was detected at the
4{\sigma} level. We also found through mapping observations that the HOOH
emission extends (about 0.05 pc) over the densest part of the {\rho} Oph A
cloud core. We derive an abundance of HOOH relative to that of H_2 in the SM1
core of about 1\times10^(-10). To our knowledge, this is the first reported
detection of HOOH in the interstellar medium.Comment: 5 pages, 4 figures, accepted for publication in Astronomy &
Astrophysics, new version corrects a typo in Table 1 (and consequently in Fig
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