211 research outputs found
Retrodirective transponder feasibility experiment
Test program on feasibility of digital phase measuring subsystem of pulse-coherent retrodirective transponde
Discontinuous Transition from a Real Bound State to Virtual Bound State in a Mixed-Valence State of SmS
Golden SmS is a paramagnetic, mixed-valence system with a pseudogap. With
increasing pressure across a critical pressure Pc, the system undergoes a
discontinuous transition into a metallic, anti-ferromagnetically ordered state.
By using a combination of thermodynamic, transport, and magnetic measurements,
we show that the pseudogap results from the formation of a local bound state
with spin singlet. We further argue that the transition Pc is regarded as a
transition from an insulating electron-hole gas to a Kondo metal, i.e., from a
spatially bound state to a Kondo virtually bound state between 4f and
conduction electrons.Comment: 5 pages, 5 figure
Cortical depth dependent functional responses in humans at 7T: improved specificity with 3D GRASE
Ultra high fields (7T and above) allow functional imaging with high contrast-to-noise ratios and improved spatial resolution. This, along with improved hardware and imaging techniques, allow investigating columnar and laminar functional responses. Using gradient-echo (GE) (T2* weighted) based sequences, layer specific responses have been recorded from human (and animal) primary visual areas. However, their increased sensitivity to large surface veins potentially clouds detecting and interpreting layer specific responses. Conversely, spin-echo (SE) (T2 weighted) sequences are less sensitive to large veins and have been used to map cortical columns in humans. T2 weighted 3D GRASE with inner volume selection provides high isotropic resolution over extended volumes, overcoming some of the many technical limitations of conventional 2D SE-EPI, whereby making layer specific investigations feasible. Further, the demonstration of columnar level specificity with 3D GRASE, despite contributions from both stimulated echoes and conventional T2 contrast, has made it an attractive alternative over 2D SE-EPI. Here, we assess the spatial specificity of cortical depth dependent 3D GRASE functional responses in human V1 and hMT by comparing it to GE responses. In doing so we demonstrate that 3D GRASE is less sensitive to contributions from large veins in superficial layers, while showing increased specificity (functional tuning) throughout the cortex compared to GE
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Ulcerative colitis-risk loci on chromosomes 1p36 and 12q15 found by genome-wide association study.
Ulcerative colitis is a chronic inflammatory disease of the colon that presents as diarrhea and gastrointestinal bleeding. We performed a genome-wide association study using DNA samples from 1,052 individuals with ulcerative colitis and preexisting data from 2,571 controls, all of European ancestry. In an analysis that controlled for gender and population structure, ulcerative colitis loci attaining genome-wide significance and subsequent replication in two independent populations were identified on chromosomes 1p36 (rs6426833, combined P = 5.1 x 10(-13), combined odds ratio OR = 0.73) and 12q15 (rs1558744, combined P = 2.5 x 10(-12), combined OR = 1.35). In addition, combined genome-wide significant evidence for association was found in a region spanning BTNL2 to HLA-DQB1 on chromosome 6p21 (rs2395185, combined P = 1.0 x 10(-16), combined OR = 0.66) and at the IL23R locus on chromosome 1p31 (rs11209026, combined P = 1.3 x 10(-8), combined OR = 0.56; rs10889677, combined P = 1.3 x 10(-8), combined OR = 1.29)
Depth dependence of itinerant character in Mn-substituted Sr3Ru2O7
We present a core-level photoemission study of Sr3(Ru 1-xMnx)2O7, in which we
monitor the evolution of the Ru-3d fine structure versus Mn substitution and
probing depth. In both Ru 3d3/2 and 3d5/2 core levels we observe a clear
suppression of the metallic features, i.e. the screened peaks, implying a sharp
transition from itinerant to localized character already at low Mn
concentrations. The comparison between soft and hard x-ray photoemission, which
provides tunable depth sensitivity, reveals that the degree of
localized/metallic character for Ru is different at the surface than in the
bulk.Comment: 10 pages, 4 figures, 1 tabl
Synthetic Associations Are Unlikely to Account for Many Common Disease Genome-Wide Association Signals
Synthetic associations have been posited as a possible explanation for missing heritability in complex disease. We show several lines of evidence which suggest that, while possible, these synthetic associations are not common
Dyspeptic symptoms and delayed gastric emptying of solids in patients with inactive Crohn’s disease
ECCO Guidelines on Therapeutics in Ulcerative Colitis: Surgical Treatment
This is the second of a series of two articles reporting the European Crohn's and Colitis Organisation [ECCO] evidence-based consensus on the management of adult patients with ulcerative colitis [UC]. The first article is focused on medical management, and the present article addresses medical treatment of acute severe ulcerative colitis [ASUC] and surgical management of medically refractory UC patients, including preoperative optimisation, surgical strategies, and technical issues. The article provides advice for a variety of common clinical and surgical conditions. Together, the articles represent an update of the evidence-based recommendations of the ECCO for UC
ECCO Guidelines on Therapeutics in Ulcerative Colitis: Medical Treatment
hese recommendations summarise the current evidence on the medical management of adult patients with UC. Gaps were iden-tified during the analysis of the data, which should be addressed by further research. Where evidence is lacking or is very weak and evidence-based recommendations cannot be given, ECCO provides alternative tools, such as Topical Reviews28,95,153–158 or Position Papers.159–161 It is important that clinicians use these guidelines within the framework of local regulations, and seek to understand and address the individual needs and expectations of every patient. We recognise that constraints on health care resources are an im-portant factor in determining whether recommendations can be implemented for patients in many countries. The recommendations outlined here should be used to inform treatment decisions and form part of an overall multidisciplinary treatment plan for patients with UC, which may also encompass psychological, nutritional, and other non-pharmacological interventions
Age-of-onset-dependent influence of NOD2 gene variants on disease behaviour and treatment in Crohn’s disease
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