3,082 research outputs found
High dispersive and monolithic 100% efficiency grisms
We present a type of grism, a series combination of transmission grating and
prism, in which we reduce the number of diffraction orders and achieve a
configuration with very high angular dispersion. The grism can be fabricated
from a single dielectric material and requires no metallic or dielectric film
layers for high transmission diffraction efficiency. One can reach 100% in the
-1st transmission diffraction order and the equal damage threshold as the
dielectric bulk material. We realized such an element in fused silica with an
efficiency of more then 99%. The bevel backside reflection is reduced by a
statistical antireflective structure, so we measured an efficiency of the
entire grism of 95% at a single wavelength
PMT Test Facility at MPIK Heidelberg and Double Chooz Super Vertical Slice
Proceedings supplement for conference poster at Neutrino 2010, Athens,
Greece
Collisions of Slow Highly Charged Ions with Surfaces
Progress in the study of collisions of multiply charged ions with surfaces is
reviewed with the help of a few recent examples. They range from fundamental
quasi-one electron processes to highly complex ablation and material
modification processes. Open questions and possible future directions will be
discussed.Comment: 13 pages, 16 figures, review pape
The freshwater crayfish Austropotamobius pallipes in South Tyrol. Heritage species and bioindicator
Rapid decline of crayfish in European freshwaters and continuing threat necessitate integrated actions in conservation and management of native crayfish populations. Besides biological reasons (diseases, plague), the impact of toxic and harmful substances (fertilisers, herbicides) or wastewater effluents, habitat alteration or fragmentation have been responsible for their decline in some regions. The same is true for the region of South Tyrol, where compared to previous investigations, only 10 of a former total of 15 crayfish locations in the water bodies could be affirmed. Although two new populations of the non-indigenous Astacus astacus were detected, the native Austropotamobius pallipes continues to decline. While many investigations have focused accurately on causal coherences for the decline of native populations, the properties of crayfish facilitate to reverse the situation. In a few examples, the potential of Austropotamobius pallipes, the native crayfish in South Tyrol, as “surrogate species” for effective biological conservation is discussed. Given the various adequate attributes of freshwater crayfish as surrogate species (including indicator species, umbrella species and flagship species qualities), they may help to advance not only the crayfish situation itself but also freshwater ecosystem properties in general
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Forward Vaccinology: CTL Targeting Based upon Physical Detection of HLA-Bound Peptides
Vaccine-elicited cytotoxic T lymphocytes (CTL) recognizing conserved fragments of a pathogen’s proteome could greatly impact infectious diseases and cancers. Enabling this potential are recent advances in mass spectrometry that identify specific target peptides among the myriad HLA-bound peptides on altered cells. Ultrasensitivity of these physical detection methods allows for the direct assessment of peptide presentation on small numbers of tissue-derived cells. In addition, concurrent advances in immunobiology suggest ways to induce CTLs with requisite functional avidity and tissue deployment. Elicitation of high-avidity resident-memory T cells through vaccination may shift the vaccinology paradigm both for preventive and therapeutic approaches to human disease control
Phase-sensitive evidence for dx2-y2-pairing symmetry in the parent-structure high-Tc cuprate superconductor Sr1-xLaxCuO2
Even after 25 years of research the pairing mechanism and - at least for
electron doped compounds - also the order parameter symmetry of the high
transition temperature (high-Tc) cuprate superconductors is still under debate.
One of the reasons is the complex crystal structure of most of these materials.
An exception are the infinite layer (IL) compounds consisting essentially of
CuO2 planes. Unfortunately, these materials are difficult to grow and, thus,
there are only few experimental investigations. Recently, we succeeded in
depositing high quality films of the electron doped IL compound Sr1-xLaxCuO2
(SLCO), with x approximately 0.15, and on the fabrication of well-defined grain
boundary Josephson junctions (GBJs) based on such SLCO films. Here we report on
a phase sensitive study of the superconducting order parameter based on GBJ
SQUIDs from a SLCO film grown on a tetracrystal substrate. Our results show
that also the parent structure of the high-Tc cuprates has dx2-y2-wave
symmetry, which thus seems to be inherent to cuprate superconductivity.Comment: Submitted to PRL, 5 pages, 3 figures, supplementary information
included (4 pages, 4 figures
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