18 research outputs found
Measuring our peculiar velocity on the CMB with high-multipole off-diagonal correlations
Our peculiar velocity with respect to the CMB rest frame is known to induce a
large dipole in the CMB. However, the motion of an observer has also the effect
of distorting the anisotropies at all scales, as shown by Challinor and Van
Leeuwen (2002), due to aberration and Doppler effects. We propose to measure
independently our local motion by using off-diagonal two-point correlation
functions for high multipoles. We study the observability of the signal for
temperature and polarization anisotropies. We point out that Planck can measure
the velocity with an error of about 30% and the direction with an error
of about 20 degrees. This method constitutes a cross-check, which can be useful
to verify that our CMB dipole is due mainly to our velocity or to disentangle
the velocity from other possible intrinsic sources. Although in this paper we
focus on our peculiar velocity, a similar effect would result also from other
intrinsic vectorial distortion of the CMB which would induce a dipolar lensing.
Measuring the off-diagonal correlation terms is therefore a test for a
preferred direction on the CMB sky.Comment: 20 pages, 4 figures. New appendix; extended analytic analysis for the
estimator; corrected expectations for EB and TB correlation
On Partial Compositeness and the CP asymmetry in charm decays
Recently, the LHCb and CDF collaborations reported the measure of an
unexpectedly large direct CP asymmetry in D meson decays. In this paper we ask
if new physics associated with Partial Compositeness could plausibly explain
this result. We find that Composite Higgs models with mass scale around 10 TeV
can account for it, while marginally satisfying all other flavor constraints in
the quark sector. The minimal framework is however inadequate in the lepton
sector due to the strong constraint from \mu\ to e \gamma. This tension can be
efficiently alleviated by realizing Partial Compositeness within Supersymmetry.
The resulting models can saturate the CP asymmetry in D decays for superpartner
masses close to the TeV scale and somewhat large A-terms. The supersymmetric
realization of Partial Compositeness also offers a predictive and
phenomenologically viable organizing principle for R-Parity violation, and may
result in very distinctive signatures at hadron colliders. With or without
Supersymmetry, the neutron EDM is expected to be around the present
experimental sensitivity.Comment: 35 pages, 2 tables, 3 figures. v2: published versio
North Atlantic simulations in Coordinated Ocean-ice Reference Experiments phase II (CORE-II). Part I: Mean states
Simulation characteristics from eighteen global ocean–sea-ice coupled models are presented with a focus on the mean Atlantic meridional overturning circulation (AMOC) and other related fields in the North Atlantic. These experiments use inter-annually varying atmospheric forcing data sets for the 60-year period from 1948 to 2007 and are performed as contributions to the second phase of the Coordinated Ocean-ice Reference Experiments (CORE-II). The protocol for conducting such CORE-II experiments is summarized. Despite using the same atmospheric forcing, the solutions show significant differences. As most models also differ from available observations, biases in the Labrador Sea region in upper-ocean potential temperature and salinity distributions, mixed layer depths, and sea-ice cover are identified as contributors to differences in AMOC. These differences in the solutions do not suggest an obvious grouping of the models based on their ocean model lineage, their vertical coordinate representations, or surface salinity restoring strengths. Thus, the solution differences among the models are attributed primarily to use of different subgrid scale parameterizations and parameter choices as well as to differences in vertical and horizontal grid resolutions in the ocean models. Use of a wide variety of sea-ice models with diverse snow and sea-ice albedo treatments also contributes to these differences. Based on the diagnostics considered, the majority of the models appear suitable for use in studies involving the North Atlantic, but some models require dedicated development effort
Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia
Embolic stroke of undetermined source: a retrospective analysis from an Italian Stroke Unit
The new clinical construct of embolic stroke of undetermined source (ESUS) suggests that many cryptogenic strokes are related to minor-risk covert embolic cardiac sources or to embolus from non-occlusive plaques in the aortic arch or in the cerebral arteries. The authors analyzed the prevalence of ESUS in a real-life condition in Italy and compared the recurrence rates in cryptogenic strokes, cardioembolic strokes, and ESUS. The authors retrospectively reassessed according to ESUS criteria 391 consecutive admissions in a stroke unit where extensive diagnostic search was routinely performed. Recurrences in each stroke type within a 3-year follow-up period (mean time: 25.44 months - standard deviation: 9.42) were also compared. The prevalence of ESUS in the aforementioned cohort was 10.5%. All ESUS patients received antiplatelet agents. Warfarin was prescribed in 56.9% of cardioembolic strokes. The recurrence rate in ESUS patients was 4.4% per year, slightly higher than in cardioembolic strokes (3.5%) and significantly higher than in cryptogenic non-ESUS (1.2%) (P<0.0001). This is the first description of a cohort of ESUS patients in an Italian stroke unit. Patients with ESUS have a significantly higher risk of recurrence than in those with non-ESUS cryptogenic strokes, and slightly higher than in those with cardioembolic strokes. Results support the hypothesis of a more extensive diagnostic evaluation in cryptogenic strokes and the feasibility of such approach
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A Prospective Study of Longitudinal Risks of Cognitive Deficit for People Undergoing Glioblastoma Surgery Using a Tablet Computer Cognition Testing Battery: Towards Personalized Understanding of Risks to Cognitive Function.
Peer reviewed: TrueFunder: NIHR Brain Injury MedTech Co-operativeGlioblastoma and the surgery to remove it pose high risks to the cognitive function of patients. Little reliable data exist about these risks, especially postoperatively before radiotherapy. We hypothesized that cognitive deficit risks detected before surgery will be exacerbated by surgery in patients with glioblastoma undergoing maximal treatment regimens. We used longitudinal electronic cognitive testing perioperatively to perform a prospective, longitudinal, observational study of 49 participants with glioblastoma undergoing surgery. Before surgery (A1), the participant risk of deficit in 5/6 cognitive domains was increased compared to normative data. Of these, the risks to Attention (OR = 31.19), Memory (OR = 97.38), and Perception (OR = 213.75) were markedly increased. These risks significantly increased in the early period after surgery (A2) when patients were discharged home or seen in the clinic to discuss histology results. For participants tested at 4-6 weeks after surgery (A3) before starting radiotherapy, there was evidence of risk reduction towards A1. The observed risks of cognitive deficit were independent of patient-specific, tumour-specific, and surgery-specific co-variates. These results reveal a timeframe of natural recovery in the first 4-6 weeks after surgery based on personalized deficit profiles for each participant. Future research in this period could investigate personalized rehabilitation tools to aid the recovery process found.Cancer Research UK (RRZB/040 and RRAG/287)
Royal College of Surgeons of England (RRAG/093)
Medical Research Council (SUAG/049 and G101-400);
National Institute for Health Research (NIHR), Career Development Fellowship for this research project (CDF-2018-11-ST2-003)
A Prospective Study of Longitudinal Risks of Cognitive Deficit for People Undergoing Glioblastoma Surgery Using a Tablet Computer Cognition Testing Battery: Towards Personalized Understanding of Risks to Cognitive Function
Glioblastoma and the surgery to remove it pose high risks to the cognitive function of patients. Little reliable data exist about these risks, especially postoperatively before radiotherapy. We hypothesized that cognitive deficit risks detected before surgery will be exacerbated by surgery in patients with glioblastoma undergoing maximal treatment regimens. We used longitudinal electronic cognitive testing perioperatively to perform a prospective, longitudinal, observational study of 49 participants with glioblastoma undergoing surgery. Before surgery (A1), the participant risk of deficit in 5/6 cognitive domains was increased compared to normative data. Of these, the risks to Attention (OR = 31.19), Memory (OR = 97.38), and Perception (OR = 213.75) were markedly increased. These risks significantly increased in the early period after surgery (A2) when patients were discharged home or seen in the clinic to discuss histology results. For participants tested at 4–6 weeks after surgery (A3) before starting radiotherapy, there was evidence of risk reduction towards A1. The observed risks of cognitive deficit were independent of patient-specific, tumour-specific, and surgery-specific co-variates. These results reveal a timeframe of natural recovery in the first 4–6 weeks after surgery based on personalized deficit profiles for each participant. Future research in this period could investigate personalized rehabilitation tools to aid the recovery process found
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CCL21 Expression in β-Cells Induces Antigen-Expressing Stromal Cell Networks in the Pancreas and Prevents Autoimmune Diabetes in Mice
Tumors induce tolerance toward their antigens by producing the chemokine CCL21, leading to the formation of tertiary lymphoid organs (TLOs). Ins2-CCL21 transgenic, nonobese diabetic (NOD) mice express CCL21 in pancreatic β-cells and do not develop autoimmune diabetes. We investigated by which mechanisms CCL21 expression prevented diabetes. Ins2-CCL21 mice develop TLOs by 4 weeks of age, consisting of naive CD4
T cells compartmentalized within networks of CD45
gp38
CD31
fibroblastic reticular cell (FRC)-like cells. Importantly, 12-week-old Ins2-CCL21 TLOs contained FRC-like cells with higher contractility, regulatory, and anti-inflammatory properties and enhanced expression of β-cell autoantigens compared with nontransgenic NOD TLOs found in inflamed islets. Consistently, transgenic mice harbored fewer autoreactive T cells and a higher proportion of regulatory T cells in the islets. Using adoptive transfer and islet transplantation models, we demonstrate that TLO formation in Ins2-CCL21 transgenic islets is critical for the regulation of autoimmunity, and although the effect is systemic, the induction is mediated locally likely by lymphocyte trafficking through TLOs. Overall, our findings suggest that CCL21 promotes TLOs that differ from inflammatory TLOs found in type 1 diabetic islets in that they resemble lymph nodes, contain FRC-like cells expressing β-cell autoantigens, and are able to induce systemic and antigen-specific tolerance leading to diabetes prevention
CCL21 Expression in β-Cells Induces Antigen-Expressing Stromal Cell Networks in the Pancreas and Prevents Autoimmune Diabetes in Mice
North and equatorial Pacific Ocean circulation in the CORE-II hindcast simulations
Highlights:
• Mean circulation patterns are assessed and Kuroshio transport is underestimated.
• Water mass distribution is compared and analyzed within COREII models.
• Main biases of deep MLDs result from the inaccurate Kuroshio separation.
• Reasonable modeled tropical dynamics but a discrepancy from the surface wind.
Abstract:
We evaluate the mean circulation patterns, water mass distributions, and tropical dynamics of the North and Equatorial Pacific Ocean based on a suite of global ocean-sea ice simulations driven by the CORE-II atmospheric forcing from 1963-2007. The first three moments (mean, standard deviation and skewness) of sea surface height and surface temperature variability are assessed against observations. Large discrepancies are found in the variance and skewness of sea surface height and in the skewness of sea surface temperature. Comparing with the observation, most models underestimate the Kuroshio transport in the Asian Marginal seas due to the missing influence of the unresolved western boundary current and meso-scale eddies. In terms of the Mixed Layer Depths (MLDs) in the North Pacific, the two observed maxima associated with Subtropical Mode Water and Central Mode Water formation coalesce into a large pool of deep MLDs in all participating models, but another local maximum associated with the formation of Eastern Subtropical Mode Water can be found in all models with different magnitudes. The main model bias of deep MLDs results from excessive Subtropical Mode Water formation due to inaccurate representation of the Kuroshio separation and of the associated excessively warm and salty Kuroshio water. Further water mass analysis shows that the North Pacific Intermediate Water can penetrate southward in most models, but its distribution greatly varies among models depending not only on grid resolution and vertical coordinate but also on the model dynamics. All simulations show overall similar large scale tropical current system, but with differences in the structures of the Equatorial Undercurrent. We also confirm the key role of the meridional gradient of the wind stress curl in driving the equatorial transport, leading to a generally weak North Equatorial Counter Current in all models due to inaccurate CORE-II equatorial wind fields. Most models show a larger interior transport of Pacific subtropical cells than the observation due to the overestimated transport in the Northern Hemisphere likely resulting from the deep pycnoclin