1,013 research outputs found
Discovery of a very extended X-ray halo around a quiescent spiral galaxy - the "missing link" of galaxy formation
Hot gaseous haloes surrounding galaxies and extending well beyond the
distribution of stars are a ubiquitous prediction of galaxy formation
scenarios. The haloes are believed to consist of gravitationally trapped gas
with a temperature of millions of Kelvin. The existence of such hot haloes
around massive elliptical galaxies has been established through their X-ray
emission. While gas out-flowing from starburst spiral galaxies has been
detected, searches for hot haloes around normal, quiescent spiral galaxies have
so far failed, casting doubts on the fundamental physics in galaxy formation
models. Here we present the first detection of a hot, large-scale gaseous halo
surrounding a normal, quiescent spiral galaxy, NGC 5746, alleviating a
long-standing problem for galaxy formation models. In contrast to starburst
galaxies, where the X-ray halo can be powered by the supernova energy, there is
no such power source in NGC 5746. The only compelling explanation is that we
are here witnessing a galaxy forming from gradually in-flowing hot and dilute
halo gas.Comment: New Astronomy, in pres
Treating glabellar lines with botulinum toxin type A-hemagglutinin complex: A review of the science, the clinical data, and patient satisfaction
Botulinum toxin type A treatment is the foundation of minimally invasive aesthetic facial procedures. Clinicians and their patients recognize the important role, both negative and positive, that facial expression, particularly the glabellar frown lines, plays in self-perception, emotional well-being, and perception by others. This article provides up-to-date information on fundamental properties and mechanisms of action of the major approved formulations of botulinum toxin type A, summarizes recent changes in naming conventions (nonproprietary names) mandated by the United States Food and Drug Administration, and describes the reasons for these changes. The request for these changes provides recognition that formulations of botulinum toxins (eg, onabotulinumtoxinA and abobotulinumtoxinA) are not interchangeable and that dosing recommendations cannot be based on any one single conversion ratio. The extensive safety, tolerability, and efficacy data are summarized in detail, including the patient-reported outcomes that contribute to overall patient satisfaction and probability treatment continuation. Based on this in-depth review, the authors conclude that botulinum toxin type A treatment remains a cornerstone of facial aesthetic treatments, and clinicians must realize that techniques and dosing from one formulation cannot be applied to others, that each patient should undergo a full aesthetic evaluation, and that products and procedures must be selected in the context of individual needs and goals
Continuous-Time Estimation of Attitude Using B-Splines on Lie Groups
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140656/1/1.g001149.pd
Tips in navigating the diagnostic complexities of chronic inflammatory demyelinating polyradiculoneuropathy
The 2021 guideline of the European Academy of Neurology/Peripheral Nerve Society on chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) includes important revisions to the previous 2010 guideline. This article highlights the new criteria and recommendations for the differential diagnosis of CIDP. In the revised guideline, the CIDP spectrum has been modified to include typical CIDP and four well-characterized CIDP variants, namely distal, multifocal/focal, motor and sensory CIDP, replacing the term ‘atypical’ CIDP. To improve the diagnosis of CIDP, the revised guideline attempts to improve the specificity of the diagnostic criteria for typical CIDP and the four CIDP variants. Specific clinical and electrodiagnostic (including both motor and sensory conduction) criteria are provided for typical CIDP and each of the CIDP variants. The levels of diagnostic certainty have been changed to CIDP and possible CIDP, with the removal of probable CIDP (due to the lack of difference in the accuracy of the electrodiagnostic criteria for probable CIDP) and definite CIDP (due to the lack of a gold standard for diagnosis). If the clinical and electrodiagnostic criteria allow only for a diagnosis of possible CIDP, cerebrospinal fluid analysis, nerve ultrasound, nerve magnetic resonance imaging, objective treatment response, and nerve biopsy can be used as supportive criteria to upgrade the diagnosis to CIDP. Although the revised guideline needs to be validated and its strengths and weaknesses assessed, using the guideline will likely improve the accuracy of diagnosis of CIDP and variants of CIDP, and aid in distinguishing CIDP from conditions with similar features.</p
Characterization of VPS34-IN1, a selective inhibitor of Vps34, reveals that the phosphatidylinositol 3-phosphate-binding SGK3 protein kinase is a downstream target of class III phosphoinositide 3-kinase
The Vps34 (vacuolar protein sorting 34) class III PI3K (phosphoinositide 3-kinase) phosphorylates PtdIns (phosphatidylinositol) at endosomal membranes to generate PtdIns(3)P that regulates membrane trafficking processes via its ability to recruit a subset of proteins possessing PtdIns(3)P-binding PX (phox homology) and FYVE domains. In the present study, we describe a highly selective and potent inhibitor of Vps34, termed VPS34-IN1, that inhibits Vps34 with 25 nM ICin vitro, but does not significantly inhibit the activity of 340 protein kinases or 25 lipid kinases tested that include all isoforms of class I as well as class II PI3Ks. Administration of VPS34-IN1 to cells induces a rapid dose-dependent dispersal of a specific PtdIns(3)P-binding probe from endosome membranes, within 1 min, without affecting the ability of class I PI3K to regulate Akt. Moreover, we explored whether SGK3 (serum- and glucocorticoid-regulated kinase-3), the only protein kinase known to interact specifically with PtdIns(3)P via its N-terminal PX domain, might be controlled by Vps34. Mutations disrupting PtdIns(3)P binding ablated SGK3 kinase activity by suppressing phosphorylation of the T-loop [PDK1 (phosphoinositide-dependent kinase 1) site] and hydrophobic motif (mammalian target of rapamycin site) residues. VPS34-IN1 induced a rapid ~50-60% loss of SGK3 phosphorylation within 1 min. VPS34-IN1 did not inhibit activity of the SGK2 isoform that does not possess a PtdIns(3)P-binding PX domain. Furthermore, class I PI3K inhibitors (GDC-0941 and BKM120) that do not inhibit Vps34 suppressed SGK3 activity by ~40%. Combining VPS34-IN1 and GDC-0941 reduced SGK3 activity ~80-90%. These data suggest SGK3 phosphorylation and hence activity is controlled by two pools of PtdIns(3)P. The first is produced through phosphorylation of PtdIns by Vps34 at the endosome. The second is due to the conversion of class I PI3K product, PtdIns(3,4,5)P3 into PtdIns(3)P, via the sequential actions of the PtdIns 5-phosphatases [SHIP1/2 (Src homology 2-domain-containing inositol phosphatase 1/2)] and PtdIns 4-phosphatase [INPP4B (inositol polyphosphate 4-phosphatase type II)]. VPS34-IN1 will be a useful probe to delineate physiological roles of the Vps34. Monitoring SGK3 phosphorylation and activity could be employed as a biomarker of Vps34 activity, in an analogous manner by which Akt is used to probe cellular class I PI3K activity. Combining class I (GDC-0941) and class III (VPS34-IN1) PI3K inhibitors could be used as a strategy to better analyse the roles and regulation of the elusive class II PI3K
Advanced Systems for Monitoring Underwater Sounds
The term "Passive Acoustic Monitoring System" (PAMS) describes a developmental sensing-and-data-acquisition system for recording underwater sounds. The sounds (more precisely, digitized and preprocessed versions from acoustic transducers) are subsequently analyzed by a combination of data processing and interpretation to identify and/or, in some cases, to locate the sources of those sounds. PAMS was originally designed to locate the sources such as fish of species that one knows or seeks to identify. The PAMS unit could also be used to locate other sources, for example, marine life, human divers, and/or vessels. The underlying principles of passive acoustic sensing and analyzing acoustic-signal data in conjunction with temperature and salinity data are not new and not unique to PAMS. Part of the uniqueness of the PAMS design is that it is the first deep-sea instrumentation design to provide a capability for studying soniferous marine animals (especially fish) over the wide depth range described below. The uniqueness of PAMS also lies partly in a synergistic combination of advanced sensing, packaging, and data-processing design features with features adapted from proven marine instrumentation systems. This combination affords a versatility that enables adaptation to a variety of undersea missions using a variety of sensors. The interpretation of acoustic data can include visual inspection of power-spectrum plots for identification of spectral signatures of known biological species or artificial sources. Alternatively or in addition, data analysis could include determination of relative times of arrival of signals at different acoustic sensors arrayed at known locations. From these times of arrival, locations of acoustic sources (and errors in those locations) can be estimated. Estimates of relative locations of sources and sensors can be refined through analysis of the attenuation of sound in the intervening water in combination with water-temperature and salinity data acquired by instrumentation systems other than PAMS. A PAMS is packaged as a battery-powered unit, mated with external sensors, that can operate in the ocean at any depth from 2 m to 1 km. A PAMS includes a pressure housing, a deep-sea battery, a hydrophone (which is one of the mating external sensors), and an external monitor and keyboard box. In addition to acoustic transducers, external sensors can include temperature probes and, potentially, underwater cameras. The pressure housing contains a computer that includes a hard drive, DC-to- DC power converters, a post-amplifier board, a sound card, and a universal serial bus (USB) 4-port hub
Group A β-Hemolytic Streptococcus Meningitis: Clinical and Microbiological Features of Nine Cases
Group A β-hemolytic streptococcus (GAS) meningitis is a rare disease in adults. We conducted a retrospective study to describe clinical and microbiological features of nine cases of GAS meningitis in Switzerland. Of nine patients, six had neurosurgical conditions, and five had upper respiratory tract infections. Eight cases were community-acquired. The outcome of GAS meningitis was favorable; only one patient died of neurosurgical complications. No patient presented with toxic shock syndrome. Serotyping failed to reveal a dominant strain, and genotyping revealed that two strains carried the gene encoding the streptococcal pyrogenic exotoxin C and that one strain carried the gene encoding the streptococcal pyrogenic exotoxin A. Our observations suggest that GAS meningitis in adults is associated with neurosurgical conditions and/or an upper respiratory tract infectio
Cosmological Simulations of Massive Compact High-z Galaxies
In order to investigate the structure and dynamics of the recently discovered
massive (M_* > 10^11 M_sun) compact z~2 galaxies, cosmological
hydrodynamical/N-body simulations of a proto-cluster region have been
undertaken. At z=2, the highest resolution simulation contains ~5800 resolved
galaxies, of which 509, 27 and 5 have M_* > 10^10 M_sun, > 10^11 M_sun and >
4x10^11 M_sun, respectively. Effective radii and characteristic stellar
densities have been determined for all galaxies. At z=2, for the definitely
well resolved mass range of M_* > 10^11 Msun, the mass-size relation is
consistent with observational findings for the most compact z~2 galaxies. The
very high velocity dispersion recently measured for a compact z~2 galaxy (~510
km/s; van Dokkum et al 2009) can be matched at about the 1-sigma level,
although a somewhat larger mass than the estimated M_* ~ 2 x 10^11 M_sun is
indicated. For the above mass range, the galaxies have an average axial ratio
= 0.64 +/- 0.02 with a dispersion of 0.1, an average rotation to 1D
velocity dispersion ratio = 0.46 +/- 0.06 with a dispersion of 0.3,
and a maximum value of v/sigma ~ 1.1. Rotation and velocity anisotropy both
contribute in flattening the compact galaxies. Some of the observed compact
galaxies appear flatter than any of the simulated galaxies. Finally, it is
found that the massive compact galaxies are strongly baryon dominated in their
inner parts, with typical dark matter mass fractions of order only 20% inside
of r=2R_eff.Comment: 10 pages, 8 figures, submitted to Ap
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