788 research outputs found
Long-term care policy: What the United States can learn from Denmark, Sweden, and the Netherlands
Paying for long-term care consumes a substantial, and growing, part of the spending on healthcare in the U.S. We examine the components and payment systems for long-term care systems in Denmark, Sweden and the Netherlands to determine what policy makers in the U.S. can learn from these countries about how to improve long-term care provision and financing in the U.S
An adaptive space-time phase field formulation for dynamic fracture of brittle shells based on LR NURBS
We present an adaptive space-time phase field formulation for dynamic
fracture of brittle shells. Their deformation is characterized by the
Kirchhoff-Love thin shell theory using a curvilinear surface description. All
kinematical objects are defined on the shell's mid-plane. The evolution
equation for the phase field is determined by the minimization of an energy
functional based on Griffith's theory of brittle fracture. Membrane and bending
contributions to the fracture process are modeled separately and a thickness
integration is established for the latter. The coupled system consists of two
nonlinear fourth-order PDEs and all quantities are defined on an evolving
two-dimensional manifold. Since the weak form requires -continuity,
isogeometric shape functions are used. The mesh is adaptively refined based on
the phase field using Locally Refinable (LR) NURBS. Time is discretized based
on a generalized- method using adaptive time-stepping, and the
discretized coupled system is solved with a monolithic Newton-Raphson scheme.
The interaction between surface deformation and crack evolution is demonstrated
by several numerical examples showing dynamic crack propagation and branching.Comment: In this version, typos were fixed, Fig. 16 is added, the literature
review is extended and clarifying explanations and remarks are added at
several places. Supplementary movies are available at
https://av.tib.eu/series/641/supplemental+videos+of+the+paper+an+adaptive+space+time+phase+field+formulation+for+dynamic+fracture+of+brittle+shells+based+on+lr+nurb
Overview of the spectrometer optical fiber feed for the Habitable-zone Planet Finder
The Habitable-zone Planet Finder (HPF) is a highly stabilized fiber fed
precision radial velocity (RV) spectrograph working in the Near Infrared (NIR):
810 - 1280 nm . In this paper we present an overview of the preparation of the
optical fibers for HPF. The entire fiber train from the telescope focus down to
the cryostat is detailed. We also discuss the fiber polishing, splicing and its
integration into the instrument using a fused silica puck. HPF was designed to
be able to operate in two modes, High Resolution (HR- the only mode mode
currently commissioned) and High Efficiency (HE). We discuss these fiber heads
and the procedure we adopted to attach the slit on to the HR fibers.Comment: Presented at 2018 SPIE Astronomical Telescopes + Instrumentation,
Austin, Texas, USA. 18 pages, 25 figures, and 2 table
Localized Deformation in Ni-Mn-Ga Single Crystals
The magnetomechanical behavior of ferromagnetic shape memory alloys such as Ni-Mn-Ga, and hence the relationship between structure and nanoscale magnetomechanical properties, is of interest for their potential applications in actuators. Furthermore, due to its crystal structure, the behavior of Ni-Mn-Ga is anisotropic. Accordingly, nanoindentation and magnetic force microscopy were used to probe the nanoscale mechanical and magnetic properties of electropolished single crystalline 10M martensitic Ni-Mn-Ga as a function of the crystallographic c-axis (easy magnetization) direction relative to the indentation surface (i.e., c-axis in-plane versus out-of-plane). Load-displacement curves from 5–10 mN indentations on in-plane regions exhibited pop-in during loading, whereas this phenomenon was absent in out-of-plane regions. Additionally, the reduced elastic modulus measured for the c-axis out-of-plane orientation was ∼50% greater than for in-plane. Although heating above the transition temperature to the austenitic phase followed by cooling to the room temperature martensitic phase led to partial recovery of the indentation deformation, the magnitude and direction of recovery depended on the original relative orientation of the crystallographic c-axis: positive recovery for the in-plane orientation versus negative recovery (i.e., increased indent depth) for out-of-plane. Moreover, the c-axis orientation for out-of-plane regions switched to in-plane upon thermal cycling, whereas the number of twins in the in-plane regions increased. We hypothesize that dislocation plasticity contributes to the permanent deformation, while pseudoelastic twinning causes pop-in during loading and large recovery during unloading in the c-axis in-plane case. Minimization of indent strain energy accounts for the observed changes in twin orientation and number following thermal cycling
Phenothiazine-mediated rescue of cognition in tau transgenic mice requires neuroprotection and reduced soluble tau burden
Abstract Background It has traditionally been thought that the pathological accumulation of tau in Alzheimer's disease and other tauopathies facilitates neurodegeneration, which in turn leads to cognitive impairment. However, recent evidence suggests that tau tangles are not the entity responsible for memory loss, rather it is an intermediate tau species that disrupts neuronal function. Thus, efforts to discover therapeutics for tauopathies emphasize soluble tau reductions as well as neuroprotection. Results Here, we found that neuroprotection alone caused by methylene blue (MB), the parent compound of the anti-tau phenothiaziazine drug, Rember™, was insufficient to rescue cognition in a mouse model of the human tauopathy, progressive supranuclear palsy (PSP) and fronto-temporal dementia with parkinsonism linked to chromosome 17 (FTDP17): Only when levels of soluble tau protein were concomitantly reduced by a very high concentration of MB, was cognitive improvement observed. Thus, neurodegeneration can be decoupled from tau accumulation, but phenotypic improvement is only possible when soluble tau levels are also reduced. Conclusions Neuroprotection alone is not sufficient to rescue tau-induced memory loss in a transgenic mouse model. Development of neuroprotective agents is an area of intense investigation in the tauopathy drug discovery field. This may ultimately be an unsuccessful approach if soluble toxic tau intermediates are not also reduced. Thus, MB and related compounds, despite their pleiotropic nature, may be the proverbial "magic bullet" because they not only are neuroprotective, but are also able to facilitate soluble tau clearance. Moreover, this shows that neuroprotection is possible without reducing tau levels. This indicates that there is a definitive molecular link between tau and cell death cascades that can be disrupted.http://deepblue.lib.umich.edu/bitstream/2027.42/78314/1/1750-1326-5-45.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78314/2/1750-1326-5-45.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/78314/3/1750-1326-5-45-S1.PDFPeer Reviewe
TOI-150: A transiting hot Jupiter in the TESS southern CVZ
We report the detection of a hot Jupiter ($M_{p}=1.75_{-0.17}^{+0.14}\
M_{J}R_{p}=1.38\pm0.04\ R_{J}\log
g=4.152^{+0.030}_{-0.043}\beta=-79.59^{\circ}$). We confirm the
planetary nature of the candidate TOI-150.01 using radial velocity observations
from the APOGEE-2 South spectrograph and the Carnegie Planet Finder
Spectrograph, ground-based photometric observations from the robotic
Three-hundred MilliMeter Telescope at Las Campanas Observatory, and Gaia
distance estimates. Large-scale spectroscopic surveys, such as APOGEE/APOGEE-2,
now have sufficient radial velocity precision to directly confirm the signature
of giant exoplanets, making such data sets valuable tools in the TESS era.
Continual monitoring of TOI-150 by TESS can reveal additional planets and
subsequent observations can provide insights into planetary system
architectures involving a hot Jupiter around a star about halfway through its
main-sequence life.Comment: 13 pages, 3 figures, 2 tables, accepted to ApJ
PhotoAffinity bits : a photoaffinity-based fragment screening platform for efficient identification of protein ligands
Advances in genomic analyses enable the identification of new proteins that are associated with disease. To validate these targets, tool molecules are required to demonstrate that a ligand can have a disease-modifying effect. Currently, as tools are reported for only a fraction of the proteome, platforms for ligand discovery are essential to leverage insights from genomic analyses. Fragment screening offers an efficient approach to explore chemical space, however, it remains challenging to develop techniques that are both sufficiently high-throughput and sensitive. We present a fragment screening platform, termed PhABits (PhotoAffinity Bits), which utilises a library of photoreactive fragments to covalently capture fragment-protein interactions. Hits can be profiled to determine potency and site of crosslinking, and subsequently developed as reporters in a competitive displacement assay to identify novel hit matter. We envision that the PhABits will be widely applicable to novel protein targets, identifying starting points in the development of therapeutic
Skp, Cullin, F-box (SCF)-Met30 and SCF-Cdc4-Mediated Proteolysis of CENP-A Prevents Mislocalization of CENP-A for Chromosomal Stability in Budding Yeast
Restricting the localization of the histone H3 variant CENP-A (Cse4 in yeast, CID in flies) tocentromeres is essential for faithful chromosome segregation. Mislocalization of CENP-Aleads to chromosomal instability (CIN) in yeast, fly and human cells. Overexpression andmislocalization of CENP-A has been observed in many cancers and this correlates withincreased invasiveness and poor prognosis. Yet genes that regulate CENP-A levels andlocalization under physiological conditions have not been defined. In this study we used agenome-wide genetic screen to identify essential genes required for Cse4 homeostasis toprevent its mislocalization for chromosomal stability. We show that two Skp, Cullin, Fbox(SCF) ubiquitin ligases with the evolutionarily conserved F-box proteins Met30 andCdc4 interact and cooperatively regulate proteolysis of endogenous Cse4 and prevent itsmislocalization for faithful chromosome segregation under physiological conditions. Theinteraction of Met30 with Cdc4 is independent of the D domain, which is essential for theirhomodimerization and ubiquitination of other substrates. The requirement for both Cdc4and Met30 for ubiquitination is specifc for Cse4; and a common substrate for Cdc4 andMet30 has not previously been described. Met30 is necessary for the interaction betweenCdc4 and Cse4, and defects in this interaction lead to stabilization and mislocalization ofCse4, which in turn contributes to CIN. We provide the first direct link between Cse4 mislocalizationto defects in kinetochore structure and show that SCF-mediated proteolysis ofPLOS Genetics Cse4 is a major mechanism that prevents stable maintenance of Cse4 at non-centromericregions, thus ensuring faithful chromosome segregation. In summary, we have identifiedessential pathways that regulate cellular levels of endogenous Cse4 and shown that proteolysisof Cse4 by SCF-Met30/Cdc4 prevents mislocalization and CIN in unperturbed cells.Fil: Au, Wei-Chun. National Institutes of Health; Estados UnidosFil: Zhang, Tianyi. National Institutes of Health; Estados UnidosFil: Mishra, Prashant K.. National Institutes of Health; Estados UnidosFil: Eisenstatt, Jessica R.. National Institutes of Health; Estados UnidosFil: Walker, Robert L.. National Institutes of Health; Estados UnidosFil: Ocampo, Josefina. National Institutes of Health; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Dawson, Anthony. National Institutes of Health; Estados UnidosFil: Warren, Jack. National Institutes of Health; Estados UnidosFil: Costanzo, Michael. University of Toronto; CanadáFil: Baryshnikova, Anastasia. California Life Company; Estados UnidosFil: Flick, Karin. University of California; Estados UnidosFil: Clark, David J.. National Institutes of Health; Estados UnidosFil: Meltzer, Paul S.. National Institutes of Health; Estados UnidosFil: Baker, Richard E.. University of Massachussets; Estados UnidosFil: Myers, Chad. University of Minnesota; Estados UnidosFil: Boone, Charles. University of Toronto; CanadáFil: Kaiser, Peter. University of California; Estados UnidosFil: Basrai, Munira A.. National Institutes of Health; Estados Unido
Detection of p-mode Oscillations in HD 35833 with NEID and TESS
We report the results of observations of p-mode oscillations in the G0
subgiant star HD 35833 in both radial velocities and photometry with NEID and
TESS, respectively. We achieve separate, robust detections of the oscillation
signal with both instruments (radial velocity amplitude m s, photometric amplitude
ppm, frequency of maximum power Hz, and
mode spacing Hz) as well as a non-detection in
a TESS sector concurrent with the NEID observations. These data shed light on
our ability to mitigate the correlated noise impact of oscillations with radial
velocities alone, and on the robustness of commonly used asteroseismic scaling
relations. The NEID data are used to validate models for the attenuation of
oscillation signals for exposure times , and we compare
our results to predictions from theoretical scaling relations and find that the
observed amplitudes are weaker than expected by , hinting at gaps in
the underlying physical models.Comment: 19 Pages, 14 Figures, Appendi
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