936 research outputs found
Note on Comparability of MicroCog Test Forms
This study investigated the differences between the Standard and Short forms of MicroCog by comparing Domain scores for a clinical sample of 351 substance abusers which gave a significant difference between scores on the Spatial Processing Domain. Implications for research and clinical use are discussed
Ecology and Management Potential for Purple Loosestrife (Lythrum salicaria)
Purple loosestrife (Lythrum salicaria), an exotic wetland plant from Eurasia, has become widespread in the northeast and northcentral regions of the U.S. and Canada. When it becomes established in a wetland, it crowds out most native plant species, and can form dense stands either in standing water or on moist soil. This results in decreased plant diversity and the loss of food and cover species valuable to wildlife. Some attempted control methods, such as controlled burning and water-level manipulation have proven to be unsuccessful. Other control measures, including mechanical cutting, replacement, and cattail competition, have shown encouraging, but inconclusive, results. This study was therefore initiated to further explore the possibility of controlling purple loosestrife through competition with cattails (Typha angustifolia) in mixed stands. A competitive edge was given to Typha by cutting Lythrum and selectively fertilizing Typha. First-year results of the study showed a significant decrease in Lythrum biomass as a result of cutting treatments. Cutting did not significantly reduce resprouting Lythrum stems, as Lythrum resprouted in greater numbers than Typha, but Typha sprouts grew faster and increased in biomass more quickly than Lythrum sprouts. With carbohydrate replenishment to the roots reduced, it is expected that Lythrum biomass will be reduced in subsequent years. The stress caused by cutting, and increased shade by the Typha canopy, may help to control purple loosestrife spread
Characterizing the Coherence of Bose-Einstein Condensates and Atom Lasers
For a dilute, interacting Bose gas of magnetically-trapped atoms at temperatures below the critical temperature T 0 for Bose-Einstein condensation, we determine the second-order coherence function g (2)(r 1, r 2) within the framework of a finite-temperature quantum field theory. We show that, because of the different spatial distributions of condensate and thermal atoms in the trap, g (2)(r 1, r 2) does not depend on |r 1 - r 2| alone. This means that the experimental determinations of g (2) reported to date give only its spatial average. Such an average may underestimate the degree of coherence attainable in an atom laser by judicious engineering of the output coupler
Persistent androgen receptor-mediated transcription in castration-resistant prostate cancer under androgen-deprived conditions
The androgen receptor (AR) is a ligand-inducible transcription factor that mediates androgen action in target tissues. Upon ligand binding, the AR binds to thousands of genomic loci and activates a cell-type specific gene program. Prostate cancer growth and progression depend on androgen-induced AR signaling. Treatment of advanced prostate cancer through medical or surgical castration leads to initial response and durable remission, but resistance inevitably develops. In castration-resistant prostate cancer (CRPC), AR activity remains critical for tumor growth despite androgen deprivation. Although previous studies have focused on ligand-dependent AR signaling, in this study we explore AR function under the androgen-deprived conditions characteristic of CRPC. Our data demonstrate that AR persistently occupies a distinct set of genomic loci after androgen deprivation in CRPC. These androgen-independent AR occupied regions have constitutively open chromatin structures that lack the canonical androgen response element and are independent of FoxA1, a transcription factor involved in ligand-dependent AR targeting. Many AR binding events occur at proximal promoters, which can act as enhancers to augment transcriptional activities of other promoters through DNA looping. We further show that androgen-independent AR binding directs a gene expression program in CRPC, which is necessary for the growth of CRPC after androgen withdrawal
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Neuronal Reprogramming for Tissue Repair and Neuroregeneration.
Stem cell and cell reprogramming technology represent a rapidly growing field in regenerative medicine. A number of novel neural reprogramming methods have been established, using pluripotent stem cells (PSCs) or direct reprogramming, to efficiently derive specific neuronal cell types for therapeutic applications. Both in vitro and in vivo cellular reprogramming provide diverse therapeutic pathways for modeling neurological diseases and injury repair. In particular, the retina has emerged as a promising target for clinical application of regenerative medicine. Herein, we review the potential of neuronal reprogramming to develop regenerative strategy, with a particular focus on treating retinal degenerative diseases and discuss future directions and challenges in the field
Infarct size and left ventricular remodelling after preventive percutaneous coronary intervention
Objective: We hypothesised that, compared with culprit-only primary percutaneous coronary intervention (PCI), additional preventive PCI in selected patients with ST-elevation myocardial infarction with multivessel disease would not be associated with iatrogenic myocardial infarction, and would be associated with reductions in left ventricular (LV) volumes in the longer term.
Methods: In the preventive angioplasty in myocardial infarction trial (PRAMI; ISRCTN73028481), cardiac magnetic resonance (CMR) was prespecified in two centres and performed (median, IQR) 3 (1, 5) and 209 (189, 957) days after primary PCI.
Results: From 219 enrolled patients in two sites, 84% underwent CMR. 42 (50%) were randomised to culprit-artery-only PCI and 42 (50%) were randomised to preventive PCI. Follow-up CMR scans were available in 72 (86%) patients. There were two (4.8%) cases of procedure-related myocardial infarction in the preventive PCI group. The culprit-artery-only group had a higher proportion of anterior myocardial infarctions (MIs) (55% vs 24%). Infarct sizes (% LV mass) at baseline and follow-up were similar. At follow-up, there was no difference in LV ejection fraction (%, median (IQR), (culprit-artery-only PCI vs preventive PCI) 51.7 (42.9, 60.2) vs 54.4 (49.3, 62.8), p=0.23), LV end-diastolic volume (mL/m2, 69.3 (59.4, 79.9) vs 66.1 (54.7, 73.7), p=0.48) and LV end-systolic volume (mL/m2, 31.8 (24.4, 43.0) vs 30.7 (23.0, 36.3), p=0.20). Non-culprit angiographic lesions had low-risk Syntax scores and 47% had non-complex characteristics.
Conclusions: Compared with culprit-only PCI, non-infarct-artery MI in the preventive PCI strategy was uncommon and LV volumes and ejection fraction were similar
The High Time Resolution Universe Survey VI: An Artificial Neural Network and Timing of 75 Pulsars
We present 75 pulsars discovered in the mid-latitude portion of the High Time
Resolution Universe survey, 54 of which have full timing solutions. All the
pulsars have spin periods greater than 100 ms, and none of those with timing
solutions are in binaries. Two display particularly interesting behaviour; PSR
J1054-5944 is found to be an intermittent pulsar, and PSR J1809-0119 has
glitched twice since its discovery.
In the second half of the paper we discuss the development and application of
an artificial neural network in the data-processing pipeline for the survey. We
discuss the tests that were used to generate scores and find that our neural
network was able to reject over 99% of the candidates produced in the data
processing, and able to blindly detect 85% of pulsars. We suggest that
improvements to the accuracy should be possible if further care is taken when
training an artificial neural network; for example ensuring that a
representative sample of the pulsar population is used during the training
process, or the use of different artificial neural networks for the detection
of different types of pulsars.Comment: 15 pages, 8 figure
The High Time Resolution Universe Pulsar Survey IV: Discovery and polarimetry of millisecond pulsars
We present the discovery of six millisecond pulsars (MSPs) in the High Time
Resolution Universe (HTRU) survey for pulsars and fast transients carried out
with the Parkes radio telescope. All six are in binary systems with
approximately circular orbits and are likely to have white dwarf companions.
PSR J1017-7156 has a high flux density and a narrow pulse width, making it
ideal for precision timing experiments. PSRs J1446-4701 and J1125-5825 are
coincident with gamma-ray sources, and folding the high-energy photons with the
radio timing ephemeris shows evidence of pulsed gamma-ray emission. PSR
J1502-6752 has a spin period of 26.7 ms, and its low period derivative implies
that it is a recycled pulsar. The orbital parameters indicate it has a very low
mass function, and therefore a companion mass much lower than usually expected
for such a mildly recycled pulsar. In addition we present polarisation profiles
for all 12 MSPs discovered in the HTRU survey to date. Similar to previous
observations of MSPs, we find that many have large widths and a wide range of
linear and circular polarisation fractions. Their polarisation profiles can be
highly complex, and although the observed position angles often do not obey the
rotating vector model, we present several examples of those that do. We
speculate that the emission heights of MSPs are a substantial fraction of the
light cylinder radius in order to explain broad emission profiles, which then
naturally leads to a large number of cases where emission from both poles is
observed.Comment: Update to correct affiliation for CAASTRO. 16 pages, 18 figures.
Accepted for publication in MNRA
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