2,541 research outputs found
Bimagnon studies in cuprates with Resonant Inelastic X-ray Scattering at the O K edge. II - The doping effect in La2-xSrxCuO4
We present RIXS data at O K edge from La2-xSrxCuO4 vs. doping between x=0.10
and x=0.22 with attention to the magnetic excitations in the Mid-Infrared
region. The sampling done by RIXS is the same as in the undoped cuprates
provided the excitation is at the first pre-peak induced by doping. Note that
this excitation energy is about 1.5 eV lower than that needed to see bimagnons
in the parent compound. This approach allows the study of the upper region of
the bimagnon continuum around 450 meV within about one third of the Brilluoin
Zone around \Gamma. The results show the presence of damped bimagnons and of
higher even order spin excitations with almost constant spectral weight at all
the dopings explored here. The implications on high Tc studies are briefly
addressed
Exchange Splitting and Charge Carrier Spin Polarization in EuO
High quality thin films of the ferromagnetic semiconductor EuO have been
prepared and were studied using a new form of spin-resolved spectroscopy. We
observed large changes in the electronic structure across the Curie and
metal-insulator transition temperature. We found that these are caused by the
exchange splitting of the conduction band in the ferromagnetic state, which is
as large as 0.6 eV. We also present strong evidence that the bottom of the
conduction band consists mainly of majority spins. This implies that doped
charge carriers in EuO are practically fully spin polarized.Comment: 4 pages, 5 figure
Stigma, health and incarceration: Turning the tide for children with a parent in prison
N
Evidence of orbital reconstruction at interfaces in La0.67Sr0.33MnO3 films
Electronic properties of transition metal oxides at interfaces are influenced
by strain, electric polarization and oxygen diffusion. Linear dichroism (LD)
x-ray absorption, diffraction, transport and magnetization on thin
La0.7Sr0.3MnO3 films, allow identification of a peculiar universal interface
effect. We report the LD signature of preferential 3d-eg(3z2-r2) occupation at
the interface, suppressing the double exchange mechanism. This surface orbital
reconstruction is opposite of that favored by residual strain and independent
of dipolar fields, chemical nature of the substrate and capping.Comment: 13 pages, 5 figure
The Effect of Cow-Diet on the Fermentation of Forages
In vitro fermentation of fresh forages minced to resemble chewed material have enabled net proteolysis and volatile fatty acid (VFA) production to be measured using rumen inocula from a cow fed lucerne hay (Burke et al., 2000). However both cow and diet affect the rumen cellulolytic bacterial populations (Weimer et al., 1999) and are able to influence in vitro digestion kinetics (Mertens et al., 1998). The objective of this study was to measure cow-diet effects on in vitro digestion and fermentation of perennial ryegrass (P; Lolium perenne), sulla (S; Hedysarum coronarium), maize (M; Zea maize) silage and mixtures
Cancer-specific variation in emergency presentation by sex, age and deprivation across 27 common and rarer cancers.
BACKGROUND: Although overall sociodemographic and cancer site variation in the risk of cancer diagnosis through emergency presentation has been previously described, relatively little is known about how this risk may vary differentially by sex, age and deprivation group between patients with a given cancer. METHODS: Data from the Routes to Diagnosis project on 749,645 patients (2006-2010) with any of 27 cancers that can occur in either sex were analysed. Crude proportions and crude and adjusted odds ratios were calculated for emergency presentation, and interactions between sex, age and deprivation with cancer were examined. RESULTS: The overall proportion of patients diagnosed through emergency presentation varied greatly by cancer. Compared with men, women were at greater risk for emergency presentation for bladder, brain, rectal, liver, stomach, colon and lung cancer (e.g., bladder cancer-specific odds ratio for women vs men, 1.50; 95% CI 1.39-1.60), whereas the opposite was true for oral/oropharyngeal cancer, lymphomas and melanoma (e.g., oropharyngeal cancer-specific odds ratio for women vs men, 0.49; 95% CI 0.32-0.73). Similarly, younger patients were at higher risk for emergency presentation for acute leukaemia, colon, stomach and oesophageal cancer (e.g., colon cancer-specific odds ratio in 35-44- vs 65-74-year-olds, 2.01; 95% CI 1.76-2.30) and older patients for laryngeal, melanoma, thyroid, oral and Hodgkin's lymphoma (e.g., melanoma specific odds ratio in 35-44- vs 65-74-year-olds, 0.20; 95% CI 0.12-0.33). Inequalities in the risk of emergency presentation by deprivation group were greatest for oral/oropharyngeal, anal, laryngeal and small intestine cancers. CONCLUSIONS: Among patients with the same cancer, the risk for emergency presentation varies notably by sex, age and deprivation group. The findings suggest that, beyond tumour biology, diagnosis through an emergency route may be associated both with psychosocial processes, which can delay seeking of medical help, and with difficulties in suspecting the diagnosis of cancer after presentation.We acknowledge the authors of previous studies that led to the creation and curation of the Routes to Diagnosis project and data set. The work presented here is a collaboration between Public Health England’s National Cancer Intelligence Network and the Cambridge Centre for Health Services Research of the University of Cambridge. GL was supported by a post-doctoral fellowship by the National Institute for Health Research (PDF-2011-04-047) to the end of 2014 and by a Cancer Research UK Clinician Scientist Fellowship award (A18180) from 2015.This is the final version of the article. It first appeared from NPG via http://dx.doi.org/10.1038/bjc.2015.5
The influence of patient case mix on public health area statistics for cancer stage at diagnosis: a cross-sectional study
This is the final version. Available on open access from OUP via the DOI in this recordBACKGROUND: statistics comparing the stage at diagnosis of geographically defined populations of cancer patients are increasingly used in public reporting to monitor geographical inequalities but may be confounded by patient case mix. We explore the impact of case-mix adjustment on a publicly reported measure of early stage at diagnosis in England. METHODS: We analyzed data used for publicly reported statistics about the stage of patients diagnosed with 1 of 11 solid tumours in 2015 in England, including information on cancer site (bladder, breast, colon, rectum, kidney, lung, melanoma, non-Hodgkin lymphoma, ovarian, prostate, endometrial), age, gender, income deprivation and population-based commissioning organization. We investigated how cancer site and other patient characteristics influence organizational comparisons and attainment of early-stage targets (≥60% of all cases diagnosed in TNM stages I-II). RESULTS: Adjusting for patient case mix reduced between-organization variance by more than 50%, resulting in appreciable discordance in organizational ranks (Kendall's tau = 0.53), with 18% (37/207) of organizations being reclassified as meeting/failing the early-stage target due to case mix. CONCLUSION: Summary statistics on stage of cancer diagnosis for geographical populations currently used as public health surveillance tools to monitor organizational inequalities need to account for patient sociodemographic characteristics and cancer site case mix.Cancer Research U
Cancer-specific variation in emergency presentation by sex, age and deprivation across 27 common and rarer cancers
This is the final version. Available on open access from Springer nature via the DOI in this recordBACKGROUND: Although overall sociodemographic and cancer site variation in the risk of cancer diagnosis through emergency presentation has been previously described, relatively little is known about how this risk may vary differentially by sex, age and deprivation group between patients with a given cancer. METHODS: Data from the Routes to Diagnosis project on 749,645 patients (2006-2010) with any of 27 cancers that can occur in either sex were analysed. Crude proportions and crude and adjusted odds ratios were calculated for emergency presentation, and interactions between sex, age and deprivation with cancer were examined. RESULTS: The overall proportion of patients diagnosed through emergency presentation varied greatly by cancer. Compared with men, women were at greater risk for emergency presentation for bladder, brain, rectal, liver, stomach, colon and lung cancer (e.g., bladder cancer-specific odds ratio for women vs men, 1.50; 95% CI 1.39-1.60), whereas the opposite was true for oral/oropharyngeal cancer, lymphomas and melanoma (e.g., oropharyngeal cancer-specific odds ratio for women vs men, 0.49; 95% CI 0.32-0.73). Similarly, younger patients were at higher risk for emergency presentation for acute leukaemia, colon, stomach and oesophageal cancer (e.g., colon cancer-specific odds ratio in 35-44- vs 65-74-year-olds, 2.01; 95% CI 1.76-2.30) and older patients for laryngeal, melanoma, thyroid, oral and Hodgkin’s lymphoma (e.g., melanoma specific odds ratio in 35-44- vs 65-74-year-olds, 0.20; 95% CI 0.12-0.33). Inequalities in the risk of emergency presentation by deprivation group were greatest for oral/oropharyngeal, anal, laryngeal and small intestine cancers. CONCLUSIONS: Among patients with the same cancer, the risk for emergency presentation varies notably by sex, age and deprivation group. The findings suggest that, beyond tumour biology, diagnosis through an emergency route may be associated both with psychosocial processes, which can delay seeking of medical help, and with difficulties in suspecting the diagnosis of cancer after presentation.National Institute for Health Research (NIHR)Cancer Research U
Bimagnon studies in cuprates with Resonant Inelastic X-ray Scattering at the O K edge. I - An assessment on La2CuO4 and a comparison with the excitation at Cu L3 and Cu K edges
We assess the capabilities of magnetic Resonant Inelastic X-ray Scattering
(RIXS) at the O edge in undoped cuprates by taking La_{2}CuO_{4} as a
benchmark case, based on a series of RIXS measurements that we present here. By
combining the experimental results with basic theory we point out the
fingerprints of bimagnon in the O edge RIXS spectra. These are a dominant
peak around 450 meV, the almost complete absence of dispersion both with
and polarization and the almost constant intensity vs. the transferred
momentum with polarization. This behavior is quite different from Cu
edge RIXS giving a strongly dispersing bimagnon tending to zero at the
center of the Brillouin zone. This is clearly shown by RIXS measurements at the
Cu edge that we present. The Cu bimagnon spectra and those at Cu
edge - both from the literature and from our data - however, have the same
shape. These similarities and differences are understood in terms of different
sampling of the bimagnon continuum. This panorama points out the unique
possibilities offered by O RIXS in the study of magnetic excitations in
cuprates near the center of the BZ
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