1,764 research outputs found
Renormalized Finite Temperature phi^4 theory from the 2PI Effective Action
We present an analytical and numerical study of scalar phi^4 theory at finite
temperature with a renormalized 2-loop truncation of the 2PI effective action.Comment: 4 pages. Presented at International Conference on Strong and
Electroweak Matter (SEWM 2006), Upton, New York, 10-13 May 200
Stability of correlated electronic systems under the influence of the electron-phonon interaction
We have used an exact diagonalization technique to study the stability of the
-Holstein and Hubbard-Holstein models under the influence of the
electron-phonon interaction. Previous results have been obtained using
frozen-phonon technique or introducing only a few dynamical phonon modes due to
the large Hilbert space. To check these results we have done exact
diagonalization in a small cluster (four sites) including all the phonon modes
allowed by symmetry. We compare our results with those obtained by using the
adiabatic approximation.Comment: 10 pages, 2 Postscript figure
Impact of Simulation Training on Undergraduate Clinical Decision-making in Emergencies: A Non-blinded, Single-centre, Randomised Pilot Study
Introduction: There is an increasing evidence base for the use of simulation-based medical education. Simulation is superior to more didactic methods for teaching a range of technical and non-technical skills, and students report they often derive more educational value from it compared with other teaching methods. There is currently limited evidence that simulation training improves clinical decision-making and, therefore, this pilot study sought to explore this further. Methods: Students were randomised to take part in either five classroom tutorials and simulation training sessions or five classroom tutorials and an online e-learning module. On completion of the teaching, students all undertook an unseen assessment scenario (managing a simulated patient with anaphylaxis), where they were scored using a weighted marking scheme. The time taken to make decisions and student-reported confidence in decisions were also measured. Results: 14/14 simulation-group participants and 12/14 e-learning-group participants completed the post-learning assessment. The simulation group identified anaphylaxis and gave adrenaline more quickly (p 0.008 and 0.005, respectively), and this cohort was more confident in making the diagnosis (p 0.044). There was no statistically significant difference between weighted global assessment scores for each group (p 0.705). The e-learning group called for help more quickly (p.0.049), although fewer students in this group called for help (five vs. nine). There was no statistical difference in confidence in decisions to administer adrenaline or call for help (p 0.539 and 0.364 respectively). Conclusions: Participants who undertook simulation training were able to more confidently and quickly identify the diagnosis and initiate emergency treatment. However, there was not a statistically significant difference between groups using an overall weighted score. Using simulation to train students to perform better in emergencies and improve their decision-making shows promise but a further quantitative study is required
Country of birth and non-small cell lung cancer incidence, treatment, and outcomes in New South Wales, Australia: a population-based linkage study.
OBJECTIVE: To compare treatment within 12 months of diagnosis, and survival by country of birth for people diagnosed with invasive non-small cell lung cancer (NSCLC) in New South Wales (NSW), Australia. DESIGN, PATIENTS, AND SETTING: A population-based cohort study of NSW residents diagnosed with NSCLC in 2003-2016 using de-identified linked data from the NSW Cancer Registry, NSW Admitted Patient Data collection, Emergency Departments, Medicare Benefits and Pharmaceutical Benefits Scheme, and National Death Index. MAIN OUTCOME MEASURES: Odds of receiving any treatment, surgery, systemic therapy, or radiotherapy respectively, in the 12 months following diagnosis were calculated using multivariable logistic regression. The hazard of death (all-cause) at one- and five-years following diagnosis was calculated using multivariable proportional hazards regression. RESULTS: 27,114 People were recorded with NSCLC in the 14-year study period. Higher percentages of older males from European countries applied in the earlier years, with a shift to younger people from South East Asia, New Zealand, and the Middle East. Adjusted analyses indicated that, compared with the Australian born, people from European countries were more likely to receive treatment, and, specifically surgery. Also, people from Asian countries were more likely to receive systemic therapy but less likely to receive radiotherapy. Survival at one- and five-years following diagnosis was higher for people born in countries other than Australia, New Zealand the United Kingdom and Germany. CONCLUSIONS: Variations exist in treatment and survival by country of birth in NSW. This may be affected by differences in factors not recorded in the NSW Registry, including use of general health services, family histories, underlying health conditions, other intrinsic factors, and cultural, social, and behavioural influences
Isochoric thermal conductivity of solid nitrogen
The isochoric thermal conductivity of solid nitrogen has been investigated on
four samples of different densities in the temperature interval from 20 K to
the onset of melting. In alfa-N2 the isochoric thermal conductivity exhibits a
dependence weaker than 1/T; in beta-N2 it increases slightly with temperature.
The experimental results are discussed within a model in which the heat is
transported by low-frequency phonons or by "diffusive" modes above the mobility
boundary. The growth of the thermal conductivity in beta-N2 is attributed to
the decreasing "rotational" component of the total thermal resistance, which
occurs as the rotational correlations between the neighboring molecules become
weaker.Comment: Postscript 12 pages, 3 figures, 1 table. To be published in 200
Integration of microRNA changes in vivo identifies novel molecular features of muscle insulin resistance in type 2 diabetes
Skeletal muscle insulin resistance (IR) is considered a critical component of type II diabetes, yet to date IR has evaded characterization at the global gene expression level in humans. MicroRNAs (miRNAs) are considered fine-scale rheostats of protein-coding gene product abundance. The relative importance and mode of action of miRNAs in human complex diseases remains to be fully elucidated. We produce a global map of coding and non-coding RNAs in human muscle IR with the aim of identifying novel disease biomarkers. We profiled >47,000 mRNA sequences and >500 human miRNAs using gene-chips and 118 subjects (n = 71 patients versus n = 47 controls). A tissue-specific gene-ranking system was developed to stratify thousands of miRNA target-genes, removing false positives, yielding a weighted inhibitor score, which integrated the net impact of both up- and down-regulated miRNAs. Both informatic and protein detection validation was used to verify the predictions of in vivo changes. The muscle mRNA transcriptome is invariant with respect to insulin or glucose homeostasis. In contrast, a third of miRNAs detected in muscle were altered in disease (n = 62), many changing prior to the onset of clinical diabetes. The novel ranking metric identified six canonical pathways with proven links to metabolic disease while the control data demonstrated no enrichment. The Benjamini-Hochberg adjusted Gene Ontology profile of the highest ranked targets was metabolic (P < 7.4 × 10-8), post-translational modification (P < 9.7 × 10-5) and developmental (P < 1.3 × 10-6) processes. Protein profiling of six development-related genes validated the predictions. Brain-derived neurotrophic factor protein was detectable only in muscle satellite cells and was increased in diabetes patients compared with controls, consistent with the observation that global miRNA changes were opposite from those found during myogenic differentiation. We provide evidence that IR in humans may be related to coordinated changes in multiple microRNAs, which act to target relevant signaling pathways. It would appear that miRNAs can produce marked changes in target protein abundance in vivo by working in a combinatorial manner. Thus, miRNA detection represents a new molecular biomarker strategy for insulin resistance, where micrograms of patient material is needed to monitor efficacy during drug or life-style interventions
Handbook on thermophysical properties of oxygen
Handbook has been compiled by Cryogenic Data Center of National Bureau of Standards. It covers thermodynamic functions, physical properties, and heat transfer data for oxygen. Handbook addresses primarily low temperature regime, but also includes some data above room temperature
Analysis of a Lennard-Jones fcc structure melting to the corresponding frozen liquid: differences between the bulk and the surface
We computed a Lennard Jones frozen liquid with a free surface using classical
molecular dynamics. The structure factor curves on the free surface of this
sample was calculated for different depths knowing that we have periodic
boundary conditions on the other parts of the sample. The resulting structure
factor curves show an horizontal shift of their first peak depending on how
deep in the sample the curves are computed. We analyze our resulting curves in
the light of spatial correlation functions during melting and at when the
liquid is frozen. The conclusion is that near the free surface the sample is
less dense than in the bulk and that the frozen liquid surface has a spatial
correlation which does not differ very much from that of the bulk. This result
is intrinsic to the melting of the Lennard Jones liquid and does not depend on
any other parameter.Comment: 18 pages 9 figure
Transport Properties of the One Dimensional Ferromagnetic Kondo Lattice Model : A Qualitative Approach to Oxide Manganites
The transport properties of the ferromagnetic Kondo lattice model in one
dimension are studied via bosonization methods. The antiferromagnetic
fluctuations, which normally appear because of the RKKY interactions, are
explicitly taken into account as a direct exchange between the ``core'' spins.
It is shown that in the paramagnetic regime with the local antiferromagnetic
fluctuations, the resistivity decays exponentially as the temperature increases
while in the ferromagnetic regime the system is an almost perfect conductor. %A
non-perturbative description of localized spin polarons %in the paramagnetic
region is obtained.
The effect of a weak applied field is discussed to be reduced to the case of
the ferromagnetic state leading to band splitting. The qualitative relevance of
the results for the problem of the Oxide Manganites is emphasized.Comment: 4 pages, REVTe
Mapping of 99 new microsatellite-derived loci in rye (Secale cereale L.) including 39 expressed sequence tags (vol 110, pg 990, 2005)
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