1,155 research outputs found
Preparation and spectroscopy of a metastable Mott insulator state with attractive interactions
We prepare and study a metastable attractive Mott insulator state formed with
bosonic atoms in a three-dimensional optical lattice. Starting from a Mott
insulator with Cs atoms at weak repulsive interactions, we use a magnetic
Feshbach resonance to tune the interactions to large attractive values and
produce a metastable state pinned by attractive interactions with a lifetime on
the order of 10 seconds. We probe the (de-)excitation spectrum via lattice
modulation spectroscopy, measuring the interaction dependence of two- and
three-body bound state energies. As a result of increased on-site three-body
loss we observe resonance broadening and suppression of tunneling processes
that produce three-body occupation.Comment: 7 pages, 6 figure
In-vitro Hepatotoxizitätsbestimmung intensivmedizinisch relevanter Hypnotika und Opioide mit der permanenten humanen Hepatozytenzelllinie Hep G2/C3A
Unter Verwendung der permanenten Hepatomzelllinie HepG2/C3AEs wurden intensivmedizinisch genutzte Sedativa, Hypnotika und Opioide auf Hepatotoxizität untersucht. Die Beurteilung der Zytotoxizität erfolgte durch lichtmikroskopische Bestimmung von Zellzahl und Vitalität, Messung der freigesetzten Laktatdehydrogenase, fluorometrische Bestimmung der Aktivität mitochondrialer Dehydrogenasen im XTT-Test sowie Syntheseleistung anhand der Mikroalbuminkonzentration. Weiterhin wurde die Aktivität des CYP1A2-Enzyms bestimmt, um Einflüsse auf die Metabolisierungsleistung zu untersuchen
Demonstration of the temporal matter-wave Talbot effect for trapped matter waves
We demonstrate the temporal Talbot effect for trapped matter waves using ultracold atoms in an optical lattice. We investigate the phase evolution of an array of essentially non-interacting matter waves and observe matter-wave collapse and revival in the form of a Talbot interference pattern. By using long expansion times, we image momentum space with sub-recoil resolution, allowing us to observe fractional Talbot fringes up to tenth order
Three-body correlation functions and recombination rates for bosons in three and one dimensions
We investigate local three-body correlations for bosonic particles in three
and one dimensions as a function of the interaction strength. The three-body
correlation function g(3) is determined by measuring the three-body
recombination rate in an ultracold gas of Cs atoms. In three dimensions, we
measure the dependence of g(3) on the gas parameter in a BEC, finding good
agreement with the theoretical prediction accounting for beyond-mean-field
effects. In one dimension, we observe a reduction of g(3) by several orders of
magnitude upon increasing interactions from the weakly interacting BEC to the
strongly interacting Tonks-Girardeau regime, in good agreement with predictions
from the Lieb-Liniger model for all strengths of interaction.Comment: 5 figure
Comparison of iron-reduced and iron-supplemented semisynthetic diets in T cell transfer colitis
Clinical observations in inflammatory bowel disease patients and experimental studies in rodents suggest that iron in the intestinal lumen derived from iron-rich food or oral iron supplementation could exacerbate inflammation and that iron depletion from the diet could be protective. To test the hypothesis that dietary iron reduction is protective against colitis development, the impact of iron reduction in the diet below 10 mg/kg on the course of CD4+ CD62L+ T cell transfer colitis was investigated in adult C57BL/6 mice. Weight loss as well as clinical and histological signs of inflammation were comparable between mice pretreated with semisynthetic diets with either < 10mg/kg iron content or supplemented with 180 mg/kg iron in the form of ferrous sulfate or hemin. Accumulation and activation of Ly6C(high) monocytes, changes in dendritic cell subset composition and induction of proinflammatory Th1/Th17 cells in the inflamed colon were not affected by the iron content of the diets. Thus, dietary iron reduction did not protect adult mice against severe intestinal inflammation in T cell transfer induced colitis
Trans-fatty acid blood levels of industrial but not natural origin are associated with cardiovascular risk factors in patients with HFpEF: a secondary analysis of the Aldo-DHF trial
BACKGROUND
Industrially processed trans-fatty acids (IP-TFA) have been linked to altered lipoprotein metabolism, inflammation and increased NT-proBNP. In patients with heart failure with preserved ejection fraction (HFpEF), associations of TFA blood levels with patient characteristics are unknown.
METHODS
This is a secondary analysis of the Aldo-DHF-RCT. From 422 patients, individual blood TFA were analyzed at baseline in n = 404 using the HS-Omega-3-Index methodology. Patient characteristics were: 67 ± 8 years, 53% female, NYHA II/III (87/13%), ejection fraction ≥ 50%, E/e' 7.1 ± 1.5; NT-proBNP 158 ng/L (IQR 82-298). A principal component analysis was conducted but not used for further analysis as cumulative variance for the first two PCs was low. Spearman's correlation coefficients as well as linear regression analyses, using sex and age as covariates, were used to describe associations of whole blood TFA with metabolic phenotype, functional capacity, echocardiographic markers for LVDF and neurohumoral activation at baseline and after 12 months.
RESULTS
Blood levels of the naturally occurring TFA C16:1n-7t were inversely associated with dyslipidemia, body mass index/truncal adiposity, surrogate markers for non-alcoholic fatty liver disease and inflammation at baseline/12Â months. Conversely, IP-TFA C18:1n9t, C18:2n6tt and C18:2n6tc were positively associated with dyslipidemia and isomer C18:2n6ct with dysglycemia. C18:2n6tt and C18:2n6ct were inversely associated with submaximal aerobic capacity at baseline/12Â months. No significant association was found between TFA and cardiac function.
CONCLUSIONS
In HFpEF patients, higher blood levels of IP-TFA, but not naturally occurring TFA, were associated with dyslipidemia, dysglycemia and lower functional capacity. Blood TFAs, in particular C16:1n-7t, warrant further investigation as prognostic markers in HFpEF. Higher blood levels of industrially processed TFA, but not of the naturally occurring TFA C16:1n-7t, are associated with a higher risk cardiometabolic phenotype and prognostic of lower aerobic capacity in patients with HFpEF
Diagnostic test accuracy in longitudinal study settings: theoretical approaches with use cases from clinical practice
Objectives
In this study, we evaluate how to estimate diagnostic test accuracy (DTA) correctly in the presence of longitudinal patient data (ie, repeated test applications per patient).
Study Design and Setting
We used a nonparametric approach to estimate the sensitivity and specificity of three tests for different target conditions with varying characteristics (ie, episode length and disease-free intervals between episodes): 1) systemic inflammatory response syndrome (n = 36), 2) depression (n = 33), and 3) epilepsy (n = 30). DTA was estimated on the levels ‘time’, ‘block’, and ‘patient-time’ for each diagnosis, representing different research questions. The estimation was conducted for the time units per minute, per hour, and per day.
Results
A comparison of DTA per and across use cases showed variations in the estimates, which resulted from the used level, the time unit, the resulting number of observations per patient, and the diagnosis-specific characteristics. Intra- and inter-use-case comparisons showed that the time-level had the highest DTA, particularly the larger the time unit, and that the patient-time-level approximated 50% sensitivity and specificity.
Conclusion
Researchers need to predefine their choices (ie, estimation levels and time units) based on their individual research aims, estimands, and diagnosis-specific characteristics of the target outcomes to make sure that unbiased and clinically relevant measures are communicated. In cases of uncertainty, researchers could report the DTA of the test using more than one estimation level and/or time unit
COVID-19 in German Competitive Sports: Protocol for a Prospective Multicenter Cohort Study (CoSmo-S)
Objective: It is unclear whether and to what extent COVID-19 infection poses health risks
and a chronic impairment of performance in athletes. Identification of individual health risk
is an important decision-making basis for managing the pandemic risk of infection with
SARS-CoV-2 in sports and return to play (RTP).
Methods: This study aims 1) to analyze the longitudinal rate of seroprevalence of SARSCoV-
2 in German athletes, 2) to assess health-related consequences in athletes infected
with SARS-CoV-2, and 3) to reveal effects of the COVID-19 pandemic in general and of a
cleared SARS-CoV-2 infection on exercise performance. CoSmo-S is a prospective
observational multicenter study establishing two cohorts: 1) athletes diagnosed positive
for COVID-19 (cohort 1) and 2) federal squad athletes who perform their annual sports
medical preparticipation screening (cohort 2). Comprehensive diagnostics including physical examination, laboratory blood analyses and blood biobanking, resting and
exercise electrocardiogram (ECG), echocardiography, spirometry and exercise testing
added by questionnaires are conducted at baseline and follow-up.
Results and Conclusion: We expect that the results obtained, will allow us to formulate
recommendations regarding RTP on a more evidence-based level
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