493 research outputs found
Tickborne Encephalitis in Naturally Exposed Monkey (Macaca sylvanus)
We describe tickborne encephalitis (TBE) in a monkey (Macaca sylvanus) after natural exposure in an area at risk for TBE. TBE virus was present in the brain and could be identified as closely related to the European subtype, strain Neudoerfl
Extremely high magnetoresistance and conductivity in the type-II Weyl semimetals WP2 and MoP2
The peculiar band structure of semimetals exhibiting Dirac and Weyl crossings
can lead to spectacular electronic properties such as large mobilities
accompanied by extremely high magnetoresistance. In particular, two closely
neighbouring Weyl points of the same chirality are protected from annihilation
by structural distortions or defects, thereby significantly reducing the
scattering probability between them. Here we present the electronic properties
of the transition metal diphosphides, WP2 and MoP2, that are type-II Weyl
semimetals with robust Weyl points. We present transport and angle resolved
photoemission spectroscopy measurements, and first principles calculations. Our
single crystals of WP2 display an extremely low residual low-temperature
resistivity of 3 nohm-cm accompanied by an enormous and highly anisotropic
magnetoresistance above 200 million % at 63 T and 2.5 K. These properties are
likely a consequence of the novel Weyl fermions expressed in this compound. We
observe a large suppression of charge carrier backscattering in WP2 from
transport measurements.Comment: Appeared in Nature Communication
The pancreas responds to remote damage and systemic stress by secretion of the pancreatic secretory proteins PSP/regI and PAP/regIII.
In patients with infection and sepsis serum levels of Pancreatic Stone protein/regenerating protein I (PSP) are highly elevated. The origin of PSP during these conditions is presumably the pancreas, however, an intestinal origin cannot be excluded. Similarly, pancreatitis-associated protein (PAP) was identified in the pancreas. These proteins were also localized in intestinal organs. Here we aim to elucidate the bio-distribution of PSP and PAP in animal models of sepsis and in healthy humans.
PSP and PAP responded to remote lesions in rats although the pancreatic response was much more pronounced than the intestinal. Tissue distribution of PSP demonstrated a 100-fold higher content in the pancreas compared to any other organ while PAP was most abundant in the small intestine. Both proteins responded to CLP or sham operation in the pancreas. PSP also increased in the intestine during CLP. The distribution of PSP and PAP in human tissue mirrored the distribution in the murine models.
Distribution of PSP and PAP was visualized by immunohistochemistry. Rats and mice underwent midline laparotomies followed by mobilization of tissue and incision of the pancreatic duct or duodenum. Standard cecum-ligation-puncture (CLP) procedures or sham laparotomies were performed. Human tissue extracts were analyzed for PSP and PAP.
The pancreas reacts to remote lesions and septic insults in mice and rats with increased PSP synthesis, while PAP is selectively responsive to septic events. Furthermore, our results suggest that serum PSP in septic patients is predominantly derived through an acute phase response of the pancreas
Cavity-enhanced high harmonic generation for XUV time-resolved ARPES
With its direct correspondence to electronic structure, angle-resolved
photoemission spectroscopy (ARPES) is a ubiquitous tool for the study of
solids. When extended to the temporal domain, time-resolved (TR)-ARPES offers
the potential to move beyond equilibrium properties, exploring both the
unoccupied electronic structure as well as its dynamical response under
ultrafast perturbation. Historically, ultrafast extreme ultraviolet (XUV)
sources employing high-order harmonic generation (HHG) have required
compromises that make it challenging to achieve a high energy resolution -
which is highly desirable for many TR-ARPES studies - while producing high
photon energies and a high photon flux. We address this challenge by performing
HHG inside a femtosecond enhancement cavity (fsEC), realizing a practical
source for TR-ARPES that achieves a flux of over 10 photons/s delivered
to the sample, operates over a range of 8-40 eV with a repetition rate of 60
MHz. This source enables TR-ARPES studies with a temporal and energy resolution
of 190 fs and 22 meV, respectively. To characterize the system, we perform
ARPES measurements of polycrystalline Au and MoTe, as well as TR-ARPES
studies on graphite.Comment: 11 pages, 5 figure
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