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Communications effect on employee anxiety and loyalty during a merger
Only in about 35 percent of mergers do companies meet their pre-merger goals. One cause of these failures is attributed to the unstable work environment created by a pending merger. Previous research has focused on post-merger attitudes of employees. The purpose of the current study was to explore communication processes in announcing a merger. Scenarios were used to simulate merger announcements
THE EASE PROGRAM: THE DEVELOPMENT OF A DISTRESS TOLERANCE INTERVENTION FOR MIDDLE SCHOOL ADOLESCENTS
Although many middle school adolescents consider the middle school grades to be an exhilarating time of momentous change in their lives, others struggle not only with academic challenges but also with the inability to handle negative emotional states. Middle school adolescents often seek ways to cope with the distress they experience. Evidence indicates that adolescents are rarely adequately equipped with the necessary skills to deal with these stressful situations. Moreover, studies indicate that their distress tolerance, defined as the ability to persist in goal directed activity while experiencing emotional distress, is associated with increased risk behavior.
Given preliminary evidence that low distress tolerance is associated with risky health behavior amongst adolescents, the overall goal of this study was to develop an adolescent appropriate intervention for improving distress tolerance skills, drawing on techniques from Dialectical Behavior therapy, with four main objectives: (1) to enable adolescents to understand the relationship between their emotions and behavior; (2) to educate adolescents on how to identify and label their emotions; (3) to teach skills to adolescents that will enable them to cope with their difficult emotions; and (4) to provide adolescents with skills that will enable them to avoid engaging in later risk behavior.
To aide in the development of this intervention, a multi-method approach was employed using focus groups (n=20), in depth interviews (n=15) and a 3 round Delphi method (n=12). Results from this study were used to develop, modify and finalize a distress tolerance intervention (EASE- Empowering Adolescents to deal with Stress and Emotions) for middle school adolescents
Aging and the rate of visual information processing
Multiple methods exist for measuring how age influences the rate of visual information processing. The most advanced methods model the processing dynamics in a task in order to estimate processing rates independently of other factors that might be influenced by age, such as overall performance level and the time at which processing onsets. However, such modeling techniques have produced mixed evidence for age effects. Using a time-accuracy function (TAF) analysis, Kliegl, Mayr, and Krampe (1994) showed clear evidence for age effects on processing rate. In contrast, using the diffusion model to examine the dynamics of decision processes, Ratcliff and colleagues (e.g., Ratcliff, Thapar, & McKoon, 2006) found no evidence for age effects on processing rate across a range of tasks. Examination of these studies suggests that the number of display stimuli might account for the different findings. In three experiments we measured the precision of younger and older adults' representations of target stimuli after different amounts of stimulus exposure. A TAF analysis found little evidence for age differences in processing rate when a single stimulus was presented (Experiment 1). However, adding three nontargets to the display resulted in age-related slowing of processing (Experiment 2). Similar slowing was observed when simply presenting two stimuli and using a post-cue to indicate the target (Experiment 3). Although there was some interference from distracting objects and from previous responses, these age-related effects on processing rate seem to reflect an age-related difficulty in processing multiple objects, particularly when encoding them into visual working memory
A Simple Kinetic Model Describes the Processivity of Myosin-V
Myosin-V is a motor protein responsible for organelle and vesicle transport
in cells. Recent single-molecule experiments have shown that it is an efficient
processive motor that walks along actin filaments taking steps of mean size
close to 36 nm. A theoretical study of myosin-V motility is presented following
an approach used successfully to analyze the dynamics of conventional kinesin
but also taking some account of step-size variations. Much of the present
experimental data for myosin-V can be well described by a two-state chemical
kinetic model with three load-dependent rates. In addition, the analysis
predicts the variation of the mean velocity and of the randomness -- a
quantitative measure of the stochastic deviations from uniform, constant-speed
motion -- with ATP concentration under both resisting and assisting loads, and
indicates a {\it sub}step of size 13-14 nm (from the ATP-binding
site) that appears to accord with independent observations.Comment: 20 pages, 7 figures, to be published in Biophys. J. in 200
Two new catalogs of blazar candidates in the WISE infrared sky
We present two catalogs of radio-loud candidate blazars whose WISE
mid-infrared colors are selected to be consistent with the colors of confirmed
gamma-ray emitting blazars. The first catalog is the improved and expanded
release of the WIBRaLS catalog presented by D'Abrusco et al. (2014): it
includes sources detected in all four WISE filters, spatially cross-matched
with radio source in one of three radio surveys and radio-loud based on their
q22 spectral parameter. WIBRaLS2 includes 9541 sources classified as BL Lacs,
FSRQs or mixed candidates based on their WISE colors. The second catalog,
called KDEBLLACS, based on a new selection technique, contains 5579 candidate
BL Lacs extracted from the population of WISE sources detected in the first
three WISE passbands ([3.4], [4.6] and [12]) only, whose mid-infrared colors
are similar to those of confirmed, gamma-ray BL Lacs. KDBLLACS members area
also required to have a radio counterpart and be radio-loud based on the
parameter q12, defined similarly to q22 used for the WIBRaLS2. We describe the
properties of these catalogs and compare them with the largest samples of
confirmed and candidate blazars in the literature. We crossmatch the two new
catalogs with the most recent catalogs of gamma-ray sources detected by Fermi
LAT instrument. Since spectroscopic observations of candidate blazars from the
first WIBRaLS catalog within the uncertainty regions of gamma-ray unassociated
sources confirmed that ~90% of these candidates are blazars, we anticipate that
these new catalogs will play again an important role in the identification of
the gamma-ray sky.Comment: 20 pages, 7 figures. Accepted for publication in The Astrophysical
Journal Supplement Serie
Elastic lever arm model for myosin V
We present a mechanochemical model for myosin V, a two-headed processive
motor protein. We derive the properties of a dimer from those of an individual
head, which we model both with a 4-state cycle (detached, attached with ADP.Pi,
attached with ADP and attached without nucleotide) and alternatively with a
5-state cycle (where the power stroke is not tightly coupled to the phosphate
release). In each state the lever arm leaves the head at a different, but
fixed, angle. The lever arm itself is described as an elastic rod. The chemical
cycles of both heads are coordinated exclusively by the mechanical connection
between the two lever arms. The model explains head coordination by showing
that the lead head only binds to actin after the power stroke in the trail head
and that it only undergoes its power stroke after the trail head unbinds from
actin. Both models (4- and 5-state) reproduce the observed hand-over-hand
motion and fit the measured force-velocity relations. The main difference
between the two models concerns the load dependence of the run length, which is
much weaker in the 5-state model. We show how systematic processivity
measurement under varying conditions could be used to distinguish between both
models and to determine the kinetic parameters.Comment: 15 pages, 15 figures, to appear in Biophys.
Optical archival spectra of blazar candidates of uncertain type in the 3 Fermi Large Area Telescope Catalog
Despite the fact that blazars constitute the rarest class among active
galactic nuclei (AGNs) they are the largest known population of associated
-ray sources. Many of the -ray objects listed in the
Fermi-Large Area Telescope Third Source catalog (3FGL) are classified as blazar
candidates of uncertain type (BCUs), either because they show multifrequency
behaviour similar to blazars but lacking optical spectra in the literature, or
because the quality of such spectra is too low to confirm their nature. Here we
select, out of 585 BCUs in the 3FGL, 42 BCUs which we identify as probable
blazars by their WISE infrared colors and which also have optical spectra that
are available in the Sloan Digital Sky Survey (SDSS) and/or Six-Degree Field
Galaxy Survey Database (6dFGS). We confirm the blazar nature of all of the
sources. We furthermore conclude that 28 of them are BL Lacs, 8 are radio-loud
quasars with flat radio spectrum and 6 are BL Lac whose emission is dominated
by their host galaxy
The Gamma-ray Blazar Quest: new optical spectra, state of art and future perspectives
We recently developed a procedure to recognize gamma-ray blazar candidates
within the positional uncertainty regions of the unidentified/unassociated
gamma-ray sources (UGSs). Such procedure was based on the discovery that Fermi
blazars show peculiar infrared colors. However, to confirm the real nature of
the selected candidates, optical spectroscopic data are necessary. Thus, we
performed an extensive archival search for spectra available in the literature
in parallel with an optical spectroscopic campaign aimed to reveal and confirm
the nature of the selected gamma-ray blazar candidates. Here, we first search
for optical spectra of a selected sample of gamma-ray blazar candidates that
can be potential counterparts of UGSs using the Sloan Digital Sky Survey (SDSS
DR12). This search enables us to update the archival search carried out to
date. We also describe the state-of-art and the future perspectives of our
campaign to discover previously unknown gamma-ray blazars.Comment: 11 pages, 2 figures, 5 tables, pre-proof version, accepted for
publication of Astrophysics and Space Scienc
Cellular Models for River Networks
A cellular model introduced for the evolution of the fluvial landscape is
revisited using extensive numerical and scaling analyses. The basic network
shapes and their recurrence especially in the aggregation structure are then
addressed. The roles of boundary and initial conditions are carefully analyzed
as well as the key effect of quenched disorder embedded in random pinning of
the landscape surface. It is found that the above features strongly affect the
scaling behavior of key morphological quantities. In particular, we conclude
that randomly pinned regions (whose structural disorder bears much physical
meaning mimicking uneven landscape-forming rainfall events, geological
diversity or heterogeneity in surficial properties like vegetation, soil cover
or type) play a key role for the robust emergence of aggregation patterns
bearing much resemblance to real river networks.Comment: 7 pages, revtex style, 14 figure
Olutasidenib (FT-2102) in patients with relapsed or refractory IDH1-mutant glioma: A multicenter, open-label, phase Ib/II trial
Brain penetration; Mutant; OlutasidenibPenetració cerebral; Mutant; OlutasidenibPenetración cerebral; Mutante; OlutasidenibBackground
Olutasidenib (FT-2102) is a highly potent, orally bioavailable, brain-penetrant and selective inhibitor of mutant isocitrate dehydrogenase 1 (IDH1). The aim of the study was to determine the safety and clinical activity of olutasidenib in patients with relapsed/refractory gliomas harboring an IDH1R132X mutation.
Methods
This was an open-label, multicenter, nonrandomized, phase Ib/II clinical trial. Eligible patients (≥18 years) had histologically confirmed IDH1R132X-mutated glioma that relapsed or progressed on or following standard therapy and had measurable disease. Patients received olutasidenib, 150 mg orally twice daily (BID) in continuous 28-day cycles. The primary endpoints were dose-limiting toxicities (DLTs) (cycle 1) and safety in phase I and objective response rate using the Modified Response Assessment in Neuro-Oncology criteria in phase II.
Results
Twenty-six patients were enrolled and followed for a median 15.1 months (7.3‒19.4). No DLTs were observed in the single-agent glioma cohort and the pharmacokinetic relationship supported olutasidenib 150 mg BID as the recommended phase II dose. In the response-evaluable population, disease control rate (objective response plus stable disease) was 48%. Two (8%) patients demonstrated a best response of partial response and eight (32%) had stable disease for at least 4 months. Grade 3‒4 adverse events (≥10%) included alanine aminotransferase increased and aspartate aminotransferase increased (three [12%], each).
Conclusions
Olutasidenib 150 mg BID was well tolerated in patients with relapsed/refractory gliomas harboring an IDH1R132X mutation and demonstrated preliminary evidence of clinical activity in this heavily pretreated population.This study was funded by Forma Therapeutics, Inc., Watertown, MA, USA
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