250 research outputs found
What Determines the ZEW Indicator?
This paper analyzes which factors are driving the ZEW Indicator of Economic Sentiment. Using the results of a poll among survey participants as well as Granger causality tests we identify three groups of influence factors: other sentiment indicators, financial variables and real economy data. In a second step these factors are used to estimate out-of-sample forecasts for the ZEW Indicator. We find that a simple model that includes German manufacturing order data, the German yield structure and the US Consumer Confidence indicator as explanatory variables is able to outperform a naive univariate benchmark model as well as the consensus forecast for the ZEW Indicator as published by news agencies. --leading indicators,Germany,zew,forecasting
What Determines the ZEW Indicator?
This paper analyzes which factors are driving the ZEW Indicator of Economic Sentiment. Using the results of a poll among survey participants as well as Granger causality tests we identify three groups of influence factors: other sentiment indicators, financial variables and real economy data. In a second step these factors are used to estimate out-of-sample forecasts for the ZEW Indicator. We find that a simple model that includes German manufacturing order data, the German yield structure and the US Consumer Confidence indicator as explanatory variables is able to outperform a naive univariate benchmark model as well as the consensus forecast for the ZEW Indicator as published by news agencies
Two-photon double ionization of neon using an intense attosecond pulse train
We present the first demonstration of two-photon double ionization of neon
using an intense extreme ultraviolet (XUV) attosecond pulse train (APT) in a
photon energy regime where both direct and sequential mechanisms are allowed.
For an APT generated through high-order harmonic generation (HHG) in argon we
achieve a total pulse energy close to 1 J, a central energy of 35 eV and a
total bandwidth of eV. The APT is focused by broadband optics in a
neon gas target to an intensity of Wcm. By tuning
the photon energy across the threshold for the sequential process the double
ionization signal can be turned on and off, indicating that the two-photon
double ionization predominantly occurs through a sequential process. The
demonstrated performance opens up possibilities for future XUV-XUV pump-probe
experiments with attosecond temporal resolution in a photon energy range where
it is possible to unravel the dynamics behind direct vs. sequential double
ionization and the associated electron correlation effects
Unexpected fourfold symmetry in the resistivity of patterned superconductors
We report the magneto-optical observation of a surprising fourfold symmetry of the flux penetration in a superconducting YBa2Cu3O7-delta thin-film disk containing a square array of antidots, leading to an angular variation of the critical current by a factor of nearly 2. This behavior is explained using a vortex channeling model. Potential applications in superconducting devices are discussed
To respond or not to respond - a personal perspective of intestinal tolerance
For many years, the intestine was one of the poor relations of the immunology world, being a realm inhabited mostly by specialists and those interested in unusual phenomena. However, this has changed dramatically in recent years with the realization of how important the microbiota is in shaping immune function throughout the body, and almost every major immunology institution now includes the intestine as an area of interest. One of the most important aspects of the intestinal immune system is how it discriminates carefully between harmless and harmful antigens, in particular, its ability to generate active tolerance to materials such as commensal bacteria and food proteins. This phenomenon has been recognized for more than 100 years, and it is essential for preventing inflammatory disease in the intestine, but its basis remains enigmatic. Here, I discuss the progress that has been made in understanding oral tolerance during my 40 years in the field and highlight the topics that will be the focus of future research
Cross-domain interference costs during concurrent verbal and spatial serial memory tasks are asymmetric
Some evidence suggests that memory for serial order is domain-general. Evidence also points to asymmetries in interference between verbal and visual-spatial tasks. We confirm that concurrently remembering verbal and spatial serial lists provokes substantial interference compared with remembering a single list, but we further investigate the impact of this interference throughout the serial position curve, where asymmetries are indeed apparent. A concurrent verbal order memory task affects spatial memory performance throughout the serial positions of the list, but performing a spatial order task affects memory for the verbal serial list only for early list items; in the verbal task only, the final items are unaffected by a concurrent task. Adding suffixes eliminates this asymmetry, resulting in impairment throughout the list for both tasks. These results suggest that domain-general working memory resources may be supplemented with resources specific to the verbal domain, but perhaps not with equivalent spatial resources
Sustained suppression by Foxp3+ regulatory T cells is vital for infectious transplantation tolerance
A new genetic mouse model demonstrates the necessity of Foxp3+ T reg cells for infectious tolerance
Low-level regulatory T-cell activity is essential for functional type-2 effector immunity to expel gastrointestinal helminths
Helminth infection is frequently associated with the expansion of regulatory T cells (Tregs) and suppression of immune responses to bystander antigens. We show that infection of mice with the chronic gastrointestinal helminth Heligmosomoides polygyrus drives rapid polyclonal expansion of Foxp3(+)Helios(+)CD4(+) thymic (t)Tregs in the lamina propria and mesenteric lymph nodes while Foxp3(+)Helios(-)CD4(+) peripheral (p)Treg expand more slowly. Notably, in partially resistant BALB/c mice parasite survival positively correlates with Foxp3(+)Helios(+)CD4(+) tTreg numbers. Boosting of Foxp3(+)Helios(+)CD4(+) tTreg populations by administration of recombinant interleukin-2 (rIL-2):anti-IL-2 (IL-2C) complex increased worm persistence by diminishing type-2 responsiveness in vivo, including suppression of alternatively activated macrophage and granulomatous responses at the sites of infection. IL-2C also increased innate lymphoid cell (ILC) numbers, indicating that Treg functions dominate over ILC effects in this setting. Surprisingly, complete removal of Tregs in transgenic Foxp3-DTR mice also resulted in increased worm burdens, with "immunological chaos" evident in high levels of the pro-inflammatory cytokines IL-6 and interferon-γ. In contrast, worm clearance could be induced by anti-CD25 antibody-mediated partial depletion of early Treg, alongside increased T helper type 2 responses and without incurring pathology. These findings highlight the overarching importance of the early Treg response to infection and the non-linear association between inflammation and the prevailing Treg frequency
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