261 research outputs found
Crossover in the nature of the metallic phases in the perovskite-type RNiO_3
We have measured the photoemission spectra of NdSmNiO,
where the metal-insulator transition and the N\'{e}el ordering occur at the
same temperature for and the metal-insulator transition
temperature () is higher than the N\'{e}el temperature for . For , the spectral intensity at the Fermi level is high in the
metallic phase above and gradually decreases with cooling in the
insulating phase below while for it shows a pseudogap-like
behavior above and further diminishes below . The results
clearly establish that there is a sharp change in the nature of the electronic
correlations in the middle () of the metallic phase of the
NiO system.Comment: 4 pages, 4 figure, submitted to Phys. Rev.
Incidence of human granulocytic anaplasmosis in returning travellers with fever.
Although tick-borne pathogens have been reported as an important cause of imported fever, the incidence of Anaplasma phagocytophilum, the causative agent of human granulocytic anaplasmosis (HGA), in travellers is unknown.
We conducted a prospective cohort study to investigate the aetiologies of fever in returning travellers (November 2017-July 2019). Polymerase chain reaction for msp2 gene amplification and indirect immunofluorescence assay for A. phagocitophilum were performed in all returning travellers with undifferentiated non-malarial fever.
Among 141 travellers included, 8 patients were diagnosed with probable or confirmed HGA. The overall incidence rate of HGA was 19.9 cases/1000 person-week of travel. The main destination of travel was Asia, accounting for 62.5% patients with HGA. Co-infections were found in 37.5% of patients with HGA.
Diagnosis of HGA and empirical treatment with doxycycline should be considered in travellers with fever
Elevated circulating metalloproteinase 7 predicts recurrent cardiovascular events in patients with carotid stenosis: a prospective cohort study
Background: Major adverse cardiovascular events are the main cause of morbidity and mortality over the long
term in patients undergoing carotid endarterectomy. There are few reports assessing the prognostic value of
markers of inflammation in relation to the risk of cardiovascular disease after carotid endarterectomy. Here, we
aimed to determine whether matrix metalloproteinases (MMP-1, MMP-2, MMP-7, MMP-9 and MMP-10), tissue
inhibitor of MMPs (TIMP-1) and in vivo inflammation studied by 18F-FDG-PET/CT predict recurrent cardiovascular
events in patients with carotid stenosis who underwent endarterectomy.
Methods: This prospective cohort study was carried out on 31 consecutive patients with symptomatic (23/31) or
asymptomatic (8/31) severe (> 70%) carotid stenosis who were scheduled for carotid endarterectomy between July
2013 and March 2016. In addition, 26 healthy controls were included in the study. Plasma and serum samples were
collected 2 days prior to surgery and tested for MMP-1, MMP-2, MMP-7, MMP-9, MMP-10, TIMP-1, high-density
lipoprotein, low-density lipoprotein, high-sensitivity C-reactive protein and erythrocyte sedimentation rate. 18F-FDGPET/CT focusing on several territoriesâ vascular wall metabolism was performed on 29 of the patients because of no
presurgical availability in 2 symptomatic patients. Histological and immunohistochemical studies were performed
with antibodies targeting MMP-10, MMP-9, TIMP-1 and CD68.
Results: The patients with carotid stenosis had significantly more circulating MMP-1, MMP-7 and MMP-10 than the
healthy controls. Intraplaque TIMP-1 was correlated with its plasma level (r = 0.42 P = .02) and with 18F-FDG uptake
(r = 0.38 P = .05). We did not find any correlation between circulating MMPs and in vivo carotid plaque metabolism
assessed by 18F-FDG-PET. After a median follow-up of 1077 days, 4 cerebrovascular, 7 cardiovascular and 11
peripheral vascular events requiring hospitalization were registered. Circulating MMP-7 was capable of predicting
events over and above the traditional risk factors (HR = 1.15 P = .006). When the model was associated with the
variables of interest, the risk predicted by 18F-FDG-PET was not significant.
Conclusions: Circulating MMP-7 may represent a novel marker for recurrent cardiovascular events in patients with
moderate to severe carotid stenosis. MMP-7 may reflect the atherosclerotic burden but not plaque inflammation in
this specific vascular territory
Primary prevention of cardiovascular disease with a Mediterranean diet
BACKGROUND:
Observational cohort studies and a secondary prevention trial have shown an inverse association between adherence to the Mediterranean diet and cardiovascular risk. We conducted a randomized trial of this diet pattern for the primary prevention of cardiovascular events.
METHODS:
In a multicenter trial in Spain, we randomly assigned participants who were at high cardiovascular risk, but with no cardiovascular disease at enrollment, to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat). Participants received quarterly individual and group educational sessions and, depending on group assignment, free provision of extra-virgin olive oil, mixed nuts, or small nonfood gifts. The primary end point was the rate of major cardiovascular events (myocardial infarction, stroke, or death from cardiovascular causes). On the basis of the results of an interim analysis, the trial was stopped after a median follow-up of 4.8 years.
RESULTS:
A total of 7447 persons were enrolled (age range, 55 to 80 years); 57% were women. The two Mediterranean-diet groups had good adherence to the intervention, according to self-reported intake and biomarker analyses. A primary end-point event occurred in 288 participants. The multivariable-adjusted hazard ratios were 0.70 (95% confidence interval [CI], 0.54 to 0.92) and 0.72 (95% CI, 0.54 to 0.96) for the group assigned to a Mediterranean diet with extra-virgin olive oil (96 events) and the group assigned to a Mediterranean diet with nuts (83 events), respectively, versus the control group (109 events). No diet-related adverse effects were reported.
CONCLUSIONS:
Among persons at high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of major cardiovascular events
Surgical treatment for colorectal cancer: Analysis of the influence of an enhanced recovery programme on long-term oncological outcomes-a study protocol for a prospective, multicentre, observational cohort study
Introduction
The evidence currently available from enhanced recovery after surgery (ERAS) programmes concerns their benefits in the immediate postoperative period, but there is still very little evidence as to whether their correct implementation benefits patients in the long term. The working hypothesis here is that, due to the lower response to surgical aggression and lower rates of postoperative complications, ERAS protocols can reduce colorectal cancer-related mortality. The main objective of this study is to analyse the impact of an ERAS programme for colorectal cancer on 5-year survival. As secondary objectives, we propose to analyse the weight of each of the predefined items in the oncological results as well as the quality of life.
Methods and analysis
A multicentre prospective cohort study was conducted in patients older than 18 years of age who are scheduled to undergo surgery for colorectal cancer. The study involved 12 hospitals with an implemented enhanced recovery protocol according to the guidelines published by the Spanish National Health Service. The intervention group includes patients with a minimum implementation level of 70%, and the control group includes those who fail to reach this level. Compliance will be studied using 18 key performance indicators, and the results will be analysed using cancer survival indicators, including overall survival, cancer-specific survival and relapse-free survival. The time to recurrence, perioperative morbidity and mortality, hospital stay and quality of life will also be studied, the latter using the validated EuroQol Five questionnaire. The propensity index method will be used to create comparable treatment and control groups, and a multivariate regression will be used to study each variable. The Kaplan-Meier estimator will be used to estimate survival and the log-rank test to make comparisons. A p value of less than 0.05 (two-tailed) will be considered to be significant.
Ethics and dissemination
Ethical approval for this study was obtained from the Aragon Ethical Committee (C.P.-C.I. PI20/086) on 4 March 2020. The findings of this study will be submitted to peer-reviewed journals (BMJ Open, JAMA Surgery, Annals of Surgery, British Journal of Surgery). Abstracts will be submitted to relevant national and international meetings.
Trial registration number NCT04305314
Dark Matter and Fundamental Physics with the Cherenkov Telescope Array
The Cherenkov Telescope Array (CTA) is a project for a next-generation
observatory for very high energy (GeV-TeV) ground-based gamma-ray astronomy,
currently in its design phase, and foreseen to be operative a few years from
now. Several tens of telescopes of 2-3 different sizes, distributed over a
large area, will allow for a sensitivity about a factor 10 better than current
instruments such as H.E.S.S, MAGIC and VERITAS, an energy coverage from a few
tens of GeV to several tens of TeV, and a field of view of up to 10 deg. In the
following study, we investigate the prospects for CTA to study several science
questions that influence our current knowledge of fundamental physics. Based on
conservative assumptions for the performance of the different CTA telescope
configurations, we employ a Monte Carlo based approach to evaluate the
prospects for detection. First, we discuss CTA prospects for cold dark matter
searches, following different observational strategies: in dwarf satellite
galaxies of the Milky Way, in the region close to the Galactic Centre, and in
clusters of galaxies. The possible search for spatial signatures, facilitated
by the larger field of view of CTA, is also discussed. Next we consider
searches for axion-like particles which, besides being possible candidates for
dark matter may also explain the unexpectedly low absorption by extragalactic
background light of gamma rays from very distant blazars. Simulated
light-curves of flaring sources are also used to determine the sensitivity to
violations of Lorentz Invariance by detection of the possible delay between the
arrival times of photons at different energies. Finally, we mention searches
for other exotic physics with CTA.Comment: (31 pages, Accepted for publication in Astroparticle Physics
Relationship between olive oil consumption and ankle-brachial pressure index in a population at high cardiovascular risk
The aim of this study was to ascertain the association between the consumption of different categories of edible olive oils (virgin olive oils and olive oil) and olive pomace oil and ankle-brachial pressure index (ABI) in participants in the PREDIMED-Plus study, a trial of lifestyle modification for weight and cardiovascular event reduction in individuals with overweight/obesity harboring the metabolic syndrome.
Methods: We performed a cross-sectional analysis of the PREDIMED-Plus trial. Consumption of any category of olive oil and olive pomace oil was assessed through a validated food-frequency questionnaire. Multivariable linear regression models were fitted to assess associations between olive oil consumption and ABI. Additionally, ABI â€1 was considered as the outcome in logistic models with different categories of olive oil and olive pomace oil as exposure.
Results: Among 4330 participants, the highest quintile of total olive oil consumption (sum of all categories of olive oil and olive pomace oil) was associated with higher mean values of ABI (beta coefficient: 0.014, 95% confidence interval [CI]: 0.002, 0.027) (p for trend = 0.010). Logistic models comparing the consumption of different categories of olive oils, olive pomace oil and ABI â€1 values revealed an inverse association between virgin olive oils consumption and the likelihood of a low ABI (odds ratio [OR] 0.73, 95% CI [0.56, 0.97]), while consumption of olive pomace oil was positively associated with a low ABI (OR 1.22 95% CI [1.00, 1.48]).
Conclusions: In a Mediterranean population at high cardiovascular risk, total olive oil consumption was associated with a higher mean ABI. These results suggest that olive oil consumption may be beneficial for peripheral artery disease prevention, but longitudinal studies are needed
Long daytime napping is associated with increased adiposity and type 2 diabetes in an elderly population with metabolic syndrome
Research examining associations between objectively-measured napping time and type
2 diabetes (T2D) is lacking. This study aimed to evaluate daytime napping in relation to T2D and
adiposity measures in elderly individuals from the Mediterranean region. A cross-sectional analysis of
baseline data from 2190 elderly participants with overweight/obesity and metabolic syndrome, in the
PREDIMED-Plus trial, was carried out. Accelerometer-derived napping was measured. Prevalence
ratios (PR) and 95% confidence intervals (CI) for T2D were obtained using multivariable-adjusted
Cox regression with constant time. Linear regression models were fitted to examine associations of
napping with body mass index (BMI) and waist circumference (WC). Participants napping â„90 min
had a higher prevalence of T2D (PR 1.37 (1.06, 1.78)) compared with those napping 5 to <30 min per
day. Significant positive associations with BMI and WC were found in those participants napping
â„30 min as compared to those napping 5 to <30 min per day. The findings of this study suggest that
longer daytime napping is associated with higher T2D prevalence and greater adiposity measures in
an elderly Spanish population at high cardiovascular risk
Dietary a-Linolenic acid, Marine x-3 fatty acids, and mortality in a population with high fish consumption: findings from the PREevenciĂłn con DIeta MEDiterrĂĄnea (PREDIMED) study
Epidemiological evidence suggests a cardioprotective role of αâlinolenic acid (ALA), a plantâderived Ïâ3 fatty acid. It is unclear whether ALA is beneficial in a background of high marine x-3 fatty acids (long-chain n-3 polyunsaturated fatty acids)
intake. In persons at high cardiovascular risk from Spain, a country in which fish consumption is customarily high, we investigated
whether meeting the International Society for the Study of Fatty Acids and Lipids recommendation for dietary ALA (0.7% of total
energy) at baseline was related to all-cause and cardiovascular disease mortality. We also examined the effect of meeting the
societyâs recommendation for long-chain n-3 polyunsaturated fatty acids (â„500 mg/day).
Methods and Results-âWe longitudinally evaluated 7202 participants in the PREvenci on con DIeta MEDiterr anea (PREDIMED) trial.
Multivariable-adjusted Cox regressionmodels were fitted to estimate hazard ratios. ALA intake correlated towalnut consumption (r=0.94).
During a 5.9-y follow-up, 431 deaths occurred (104 cardiovascular disease, 55 coronary heart disease, 32 sudden cardiac death, 25
stroke). The hazard ratios formeeting ALArecommendation (n=1615, 22.4%) were 0.72 (95% CI 0.56â0.92) for all-causemortality and 0.95
(95% CI 0.58â1.57) for fatal cardiovascular disease. The hazard ratios formeeting the recommendation for long-chain n-3 polyunsaturated
fatty acids (n=5452, 75.7%) were 0.84 (95% CI 0.67â1.05) for all-causemortality, 0.61 (95% CI 0.39â0.96) for fatal cardiovascular disease,
0.54 (95% CI 0.29â0.99) for fatal coronary heart disease, and 0.49 (95% CI 0.22â1.01) for sudden cardiac death. The highest reduction in
all-cause mortality occurred in participants meeting both recommendations (hazard ratio 0.63 [95% CI 0.45â0.87]).
Conclusions-âIn participants without prior cardiovascular disease and high fish consumption, dietary ALA, supplied mainly by
walnuts and olive oil, relates inversely to all-cause mortality, whereas protection from cardiac mortality is limited to fish-derived
long-chain n-3 polyunsaturated fatty acids
Search for dark matter produced in association with a single top quark and an energetic W boson in âs= 13 TeV pp collisions with the ATLAS detector
This paper presents a search for dark matter, Ï , using events with a single top quark and an energetic W boson. The analysis is based on protonâproton collision data collected with the ATLAS experiment at s= 13 TeV during LHC Run 2 (2015â2018), corresponding to an integrated luminosity of 139 fb . The search considers final states with zero or one charged lepton (electron or muon), at least one b-jet and large missing transverse momentum. In addition, a result from a previous search considering two-charged-lepton final states is included in the interpretation of the results. The data are found to be in good agreement with the Standard Model predictions and the results are interpreted in terms of 95% confidence-level exclusion limits in the context of a class of dark matter models involving an extended two-Higgs-doublet sector together with a pseudoscalar mediator particle. The search is particularly sensitive to on-shell production of the charged Higgs boson state, H , arising from the two-Higgs-doublet mixing, and its semi-invisible decays via the mediator particle, a: Hâ Wa(â ÏÏ) . Signal models with H masses up to 1.5 TeV and a masses up to 350 GeV are excluded assuming a tan ÎČ value of 1. For masses of a of 150 (250) GeV, tan ÎČ values up to 2 are excluded for H masses between 200 (400) GeV and 1.5 TeV. Signals with tan ÎČ values between 20 and 30 are excluded for H masses between 500 and 800 GeV
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