333 research outputs found
Clinicopathological and Genomic Characterization of a Simmental Calf with Generalized Bovine Juvenile Angiomatosis
Bovine juvenile angiomatosis (BJA) comprises a group of single or multiple proliferative vascular anomalies in the skin and viscera of affected calves. The purpose of this study was to characterize the clinicopathological phenotype of a 1.5-month-old Simmental calf with multiple cutaneous, subcutaneous, and visceral vascular hamartomas, which were compatible with a generalized form of BJA, and to identify genetic cause for this phenotype by whole-genome sequencing (WGS). The calf was referred to the clinics as a result of its failure to thrive and the presence of multiple cutaneous and subcutaneous nodules, some of which bled abundantly following spontaneous rupture. Gross pathology revealed similar lesions at the inner thoracic wall, diaphragm, mediastinum, pericardium, inner abdominal wall, and mesentery. Histologically, variably sized cavities lined by a single layer of plump cells and supported by a loose stroma with occasional acute hemorrhage were observed. Determined by immunochemistry, the plump cells lining the cavities displayed a strong cytoplasmic signal for PECAM-1, von Willebrand factor, and vimentin. WGS revealed six private protein-changing variants affecting different genes present in the calf and absent in more than 4500 control genomes. Assuming a spontaneous de novo mutation event, one of the identified variants found in the PREX1, UBE3B, PCDHGA2, and ZSWIM6 genes may represent a possible candidate pathogenic variant for this rare form of vascular malformation
Shape modeling technique KOALA validated by ESA Rosetta at (21) Lutetia
We present a comparison of our results from ground-based observations of
asteroid (21) Lutetia with imaging data acquired during the flyby of the
asteroid by the ESA Rosetta mission. This flyby provided a unique opportunity
to evaluate and calibrate our method of determination of size, 3-D shape, and
spin of an asteroid from ground-based observations. We present our 3-D
shape-modeling technique KOALA which is based on multi-dataset inversion. We
compare the results we obtained with KOALA, prior to the flyby, on asteroid
(21) Lutetia with the high-spatial resolution images of the asteroid taken with
the OSIRIS camera on-board the ESA Rosetta spacecraft, during its encounter
with Lutetia. The spin axis determined with KOALA was found to be accurate to
within two degrees, while the KOALA diameter determinations were within 2% of
the Rosetta-derived values. The 3-D shape of the KOALA model is also confirmed
by the spectacular visual agreement between both 3-D shape models (KOALA pre-
and OSIRIS post-flyby). We found a typical deviation of only 2 km at local
scales between the profiles from KOALA predictions and OSIRIS images, resulting
in a volume uncertainty provided by KOALA better than 10%. Radiometric
techniques for the interpretation of thermal infrared data also benefit greatly
from the KOALA shape model: the absolute size and geometric albedo can be
derived with high accuracy, and thermal properties, for example the thermal
inertia, can be determined unambiguously. We consider this to be a validation
of the KOALA method. Because space exploration will remain limited to only a
few objects, KOALA stands as a powerful technique to study a much larger set of
small bodies using Earth-based observations.Comment: 15 pages, 8 figures, 2 tables, accepted for publication in P&S
Surface-Energy Control and Characterization of Nanoparticle Coatings
Accurate and reproducible measurement of the structure and properties of high-value nanoparticles is extremely important for their commercialization. A significant proportion of engineered nanoparticle systems consist of some form of nominally core\u2013shell structure, whether by design or unintentionally. Often, these do not form an ideal core\u2013shell structure, with typical deviations including polydispersity of the core or shell, uneven or incomplete shells, noncentral cores, and others. Such systems may be created with or without intent, and in either case an understanding of the conditions for formation of such particles is desirable. Precise determination of the structure, composition, size, and shell thickness of such particles can prove challenging without the use of a suitable range of characterization techniques. Here, the authors present two such polymer core\u2013shell nanoparticle systems, consisting of polytetrafluoroethylene cores coated with a range of thicknesses of either polymethylmethacrylate or polystyrene. By consideration of surface energy, it is shown that these particles are expected to possess distinctly differing coating structures, with the polystyrene coating being incomplete. A comprehensive characterization of these systems is demonstrated, using a selection of complementary techniques including scanning electron microscopy, scanning transmission electron microscopy, thermogravimetric analysis, dynamic light scattering, differential centrifugal sedimentation, and X-ray photoelectron spectroscopy. By combining the results provided by these techniques, it is possible to achieve superior characterization and understanding of the particle structure than could be obtained by considering results separately
Tuning of the elastic modulus of a soft polythiophene through molecular doping
Molecular doping of a polythiophene with oligoethylene glycol side chains is found to strongly modulate not only the electrical but also the mechanical properties of the polymer. An oxidation level of up to 18% results in an electrical conductivity of more than 52 S cm(-1) and at the same time significantly enhances the elastic modulus from 8 to more than 200 MPa and toughness from 0.5 to 5.1 MJ m(-3). These changes arise because molecular doping strongly influences the glass transition temperature T-g and the degree of pi-stacking of the polymer, as indicated by both X-ray diffraction and molecular dynamics simulations. Surprisingly, a comparison of doped materials containing mono- or dianions reveals that - for a comparable oxidation level - the presence of multivalent counterions has little effect on the stiffness. Evidently, molecular doping is a powerful tool that can be used for the design of mechanically robust conducting materials, which may find use within the field of flexible and stretchable electronics
Limit on the Radiative Neutrinoless Double Electron Capture of Ar from GERDA Phase I
Neutrinoless double electron capture is a process that, if detected, would
give evidence of lepton number violation and the Majorana nature of neutrinos.
A search for neutrinoless double electron capture of Ar has been
performed with germanium detectors installed in liquid argon using data from
Phase I of the GERmanium Detector Array (GERDA) experiment at the Gran Sasso
Laboratory of INFN, Italy. No signal was observed and an experimental lower
limit on the half-life of the radiative neutrinoless double electron capture of
Ar was established: 3.6 10 yr at 90 % C.I.Comment: 7 pages, 3 figure
Multiplicities of charged pions and unidentified charged hadrons from deep-inelastic scattering of muons off an isoscalar target
Multiplicities of charged pions and unidentified hadrons produced in
deep-inelastic scattering were measured in bins of the Bjorken scaling variable
, the relative virtual-photon energy and the relative hadron energy .
Data were obtained by the COMPASS Collaboration using a 160 GeV muon beam and
an isoscalar target (LiD). They cover the kinematic domain in the photon
virtuality > 1(GeV/c, , and . In addition, a leading-order pQCD analysis was performed using the
pion multiplicity results to extract quark fragmentation functions
Model-independent evidence for contributions to decays
The data sample of decays acquired with the
LHCb detector from 7 and 8~TeV collisions, corresponding to an integrated
luminosity of 3 fb, is inspected for the presence of or
contributions with minimal assumptions about
contributions. It is demonstrated at more than 9 standard deviations that
decays cannot be described with
contributions alone, and that contributions play a dominant role in
this incompatibility. These model-independent results support the previously
obtained model-dependent evidence for charmonium-pentaquark
states in the same data sample.Comment: 21 pages, 12 figures (including the supplemental section added at the
end
Quantum numbers of the state and orbital angular momentum in its decay
Angular correlations in decays, with , and , are used to measure
orbital angular momentum contributions and to determine the value of
the meson. The data correspond to an integrated luminosity of 3.0
fb of proton-proton collisions collected with the LHCb detector. This
determination, for the first time performed without assuming a value for the
orbital angular momentum, confirms the quantum numbers to be .
The is found to decay predominantly through S wave and an upper limit
of at C.L. is set on the fraction of D wave.Comment: 16 pages, 4 figure
Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics
A detailed study is presented of the expected performance of the ATLAS
detector. The reconstruction of tracks, leptons, photons, missing energy and
jets is investigated, together with the performance of b-tagging and the
trigger. The physics potential for a variety of interesting physics processes,
within the Standard Model and beyond, is examined. The study comprises a series
of notes based on simulations of the detector and physics processes, with
particular emphasis given to the data expected from the first years of
operation of the LHC at CERN
Evaluation of presumably disease causing SCN1A variants in a cohort of common epilepsy syndromes
Objective: The SCN1A gene, coding for the voltage-gated Na+ channel alpha subunit NaV1.1, is the clinically most relevant epilepsy gene. With the advent of high-throughput next-generation sequencing, clinical laboratories are generating an ever-increasing catalogue of SCN1A variants. Variants are more likely to be classified as pathogenic if they have already been identified previously in a patient with epilepsy. Here, we critically re-evaluate the pathogenicity of this class of variants in a cohort of patients with common epilepsy syndromes and subsequently ask whether a significant fraction of benign variants have been misclassified as pathogenic. Methods: We screened a discovery cohort of 448 patients with a broad range of common genetic epilepsies and 734 controls for previously reported SCN1A mutations that were assumed to be disease causing. We re-evaluated the evidence for pathogenicity of the identified variants using in silico predictions, segregation, original reports, available functional data and assessment of allele frequencies in healthy individuals as well as in a follow up cohort of 777 patients. Results and Interpretation: We identified 8 known missense mutations, previously reported as pathogenic, in a total of 17 unrelated epilepsy patients (17/448; 3.80%). Our re-evaluation indicates that 7 out of these 8 variants (p.R27T; p.R28C; p.R542Q; p.R604H; p.T1250M; p.E1308D; p.R1928G; NP-001159435.1) are not pathogenic. Only the p.T1174S mutation may be considered as a genetic risk factor for epilepsy of small effect size based on the enrichment in patients (P = 6.60
7 10-4; OR = 0.32, fishers exact test), previous functional studies but incomplete penetrance. Thus, incorporation of previous studies in genetic counseling of SCN1A sequencing results is challenging and may produce incorrect conclusions
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