155 research outputs found
Clustering of Very Red Galaxies in the Las Campanas IR Survey
We report results from the first 1000 square arc-minutes of the Las Campanas
IR survey. We have imaged 1 square degree of high latitude sky in six distinct
fields to a 5-sigma H-band depth of 20.5 (Vega). Optical imaging in the
V,R,I,and z' bands allow us to select color subsets and
photometric-redshift-defined shells. We show that the angular clustering of
faint red galaxies (18 3) is an order of magnitude stronger
than that of the complete H-selected field sample. We employ three approaches
to estimate in order to invert w(theta) to derive r_0. We find that our
n(z) is well described by a Gaussian with = 1.2, sigma(z) = 0.15. From this
we derive a value for r_0 of 7 (+2,-1) co-moving H^{-1} Mpc at = 1.2. This
is a factor of ~ 2 larger than the clustering length for Lyman break galaxies
and is similar to the expectation for early type galaxies at this epoch.Comment: 5 pages, 2 figures, 1 table. To appear in proceedings of the
ESO/ECF/STScI workshop "Deep Fields" held in Garching, Germany, 9-12 October
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Eyetracking metrics reveal impaired spatial anticipation in behavioural variant frontotemporal dementia.
Eyetracking technology has had limited application in the dementia field to date, with most studies attempting to discriminate syndrome subgroups on the basis of basic oculomotor functions rather than higher-order cognitive abilities. Eyetracking-based tasks may also offer opportunities to reduce or ameliorate problems associated with standard paper-and-pencil cognitive tests such as the complexity and linguistic demands of verbal test instructions, and the problems of tiredness and attention associated with lengthy tasks that generate few data points at a slow rate. In the present paper we adapted the Brixton spatial anticipation test to a computerized instruction-less version where oculomotor metrics, rather than overt verbal responses, were taken into account as indicators of high level cognitive functions. Twelve bvFTD (in whom spatial anticipation deficits were expected), six SD patients (in whom deficits were predicted to be less frequent) and 38 healthy controls were presented with a 10 Ć 7 matrix of white circles. During each trial (N = 24) a black dot moved across seven positions on the screen, following 12 different patterns. Participants' eye movements were recorded. Frequentist statistical analysis of standard eye movement metrics were complemented by a Bayesian machine learning (ML) approach in which raw eyetracking time series datasets were examined to explore the ability to discriminate diagnostic group performance not only on the overall performance but also on individual trials. The original pen and paper Brixton test identified a spatial anticipation deficit in 7/12 (58%) of bvFTD and in 2/6 (33%) of SD patients. The eyetracking frequentist approach reported the deficit in 11/12 (92%) of bvFTD and in none (0%) of the SD patients. The machine learning approach had the main advantage of identifying significant differences from controls in 24/24 individual trials for bvFTD patients and in only 12/24 for SD patients. Results indicate that the fine grained rich datasets obtained from eyetracking metrics can inform us about high level cognitive functions in dementia, such as spatial anticipation. The ML approach can help identify conditions where subtle deficits are present and, potentially, contribute to test optimisation and the reduction of testing times. The absence of instructions also favoured a better distinction between different clinical groups of patients and can help provide valuable disease-specific markers
Receptor-targeted peptide conjugates based on diphosphines enable preparation of 99mTc and 188Re theranostic agents for prostate cancer
Benchtop 99Mo/ 99mTc and 188W/ 188Re generators enable economical production of molecular theranostic 99mTc and 188Re radiopharmaceuticals, provided that simple, kit-based chemistry exists to radiolabel targeting vectors with these radionuclides. We have previously described a diphosphine platform that efficiently incorporates 99mTc into receptor-targeted peptides. Here, we report its application to label a prostate-specific membrane antigen (PSMA)-targeted peptide with 99mTc and 188Re for diagnostic imaging and systemic radiotherapy of prostate cancer. Methods: Two diphosphine-dipeptide bioconjugates, DP1-PSMAt and DP2-PSMAt, were formulated into kits for radiolabeling with 99mTc and 188Re. The resulting radiotracers were studied in vitro, in prostate cancer cells, and in vivo in mouse xenograft models, to assess similarity of uptake and biodistribution for each 99mTc/ 188Re pair of agents. Results: Both DP1-PSMAt and DP2-PSMAt could be efficiently radiolabeled with 99mTc and 188Re using kit-based methods to furnish the isostructural compounds M-DP1-PSMAt and M-DP2-PSMAt (M = [ 99mTc]Tc, [ 188Re]Re). All 99mTc/ 188Re radiotracers demonstrated specific uptake in PSMA-expressing prostate cancer cells, with negligible uptake in prostate cancer cells that did not express PSMA or in which PSMA uptake was blocked. M-DP1-PSMAt and M-DP2-PSMAt also exhibited high tumor uptake (18-30 percentage injected dose per gram at 2āh after injection), low retention in nontarget organs, fast blood clearance, and excretion predominantly via a renal pathway. Importantly, each pair of 99mTc/ 188Re radiotracers showed near-identical biologic behavior in these experiments. Conclusion: We have prepared and developed novel pairs of isostructural PSMA-targeting 99mTc/ 188Re theranostic agents. These generator-based theranostic agents have potential to provide access to the benefits of PSMA-targeted diagnostic imaging and systemic radiotherapy in health care settings that do not routinely have access to either reactor-produced 177Lu radiopharmaceuticals or PET/CT infrastructure. </p
The ICASSP SP Cadenza Challenge: Music Demixing/Remixing for Hearing Aids
This paper reports on the design and results of the 2024 ICASSP SP Cadenza
Challenge: Music Demixing/Remixing for Hearing Aids. The Cadenza project is
working to enhance the audio quality of music for those with a hearing loss.
The scenario for the challenge was listening to stereo reproduction over
loudspeakers via hearing aids. The task was to: decompose pop/rock music into
vocal, drums, bass and other (VDBO); rebalance the different tracks with
specified gains and then remixing back to stereo. End-to-end approaches were
also accepted. 17 systems were submitted by 11 teams. Causal systems performed
poorer than non-causal approaches. 9 systems beat the baseline. A common
approach was to fine-tuning pretrained demixing models. The best approach used
an ensemble of models.Comment: 2-page paper for ICASSP 2024 SP Grand Challeng
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Empathy at the heart of darkness: empathy deficits that bind the dark triad and those that mediate indirect relational aggression
The dark triad (DT) traitsāpsychopathy, narcissism and Machiavellianismāhave collectively been linked to reduced empathy and increased aggression; however, their association with distinct empathic subtypes remains unclear; and unique links to indirect relational aggression (IRA) have not been delineated. Moreover, whether dark traits should be conceptualized individually, as a dyad or as a triad with a dark core centered around the absence of empathy is debated. The current study examines (i) whether impaired empathy indeed represents a common ādark coreā binding Machiavellianism, narcissism, and psychopathy, and (ii) this core explains associations between the dark traits and IRA. Participants (N = 301, 262 F/39 M) completed measures of the DT traits, cognitive and affective empathy components and IRA (Social Exclusion, Malicious Humor and Guilt Induction). The individual traits model without links between narcissism and IRA showed the best fit, suggesting that, at least in the context of IRA, the DT traits are best viewed as three independent personality traits. Distinct cognitive and affective empathy deficits and capacities are seen in the DT. Peripheral responsivity was the only type of empathy deficit associated with all dark traits, but unrelated to IRA. Psychopathy was the strongest indicator of impaired empathy and all IRAs; however, only online simulation, an affect-related cognitive empathy facet, partially mediated the relationships of psychopathy and Machiavellianism with IRA. Whilst the unique pathways for the dark triad traits suggest stronger alignment of psychopathy and Machiavellianism in their empathic deficits and indirect aggression; the data do not support the notion that an unempathic dark core underpinning all three traits drives indirect aggression. This is the first paper delineating the specific empathic deficits involved using a facet approach and their link to indirect forms of aggression. Results therefore inform theoretical models of aggression in the DT and offer some clarity on the debates surrounding the unempathic dark core in the DT
The 2nd Clarity Prediction Challenge: A machine learning challenge for hearing aid intelligibility prediction
This paper reports on the design and outcomes of the 2nd Clarity Prediction Challenge (CPC2) for predicting the intelligibility of hearing aid processed signals heard by individuals with a hearing impairment. The challenge was designed to promote new approaches for estimating the intelligibility of hearing aid signals that can be used in future hearing aid algorithm development. It extends an earlier round (CPC1, 2022) in a number of critical directions, including a larger dataset coming from new speech intelligibility listening experiments, a greater degree of variability in the test materials, and a design that requires prediction systems to generalise to unseen algorithms and listeners. This paper provides a full description of the new publicly available CPC2 dataset, the CPC2 challenge design, and the baseline systems. The challenge attracted 12 systems from 9 research teams. The systems are reviewed, their performance is analysed and conclusions are presented, with reference to the progress made since the earlier CPC1 challenge. In particular, it is seen how reference-free, non-intrusive systems based on pre-trained large acoustic models can perform well in this context
From St. Petersburg to Krushchev\u27s Boot
Program for the first annual RISD Cabaret held in Memorial Hall. Design and layout by Justin Kerr.https://digitalcommons.risd.edu/liberalarts_cabaret_programs/1000/thumbnail.jp
Muddy, muddled, or muffled? Understanding the perception of audio quality in music by hearing aid users
Introduction: Previous work on audio quality evaluation has demonstrated a developing convergence of the key perceptual attributes underlying judgments of quality, such as timbral, spatial and technical attributes. However, across existing research there remains a limited understanding of the crucial perceptual attributes that inform audio quality evaluation for people with hearing loss, and those who use hearing aids. This is especially the case with music, given the unique problems it presents in contrast to human speech. Method: This paper presents a sensory evaluation study utilising descriptive analysis methods, in which a panel of hearing aid users collaborated, through consensus, to identify the most important perceptual attributes of music audio quality and developed a series of rating scales for future listening tests. Participants (N = 12), with a hearing loss ranging from mild to severe, first completed an online elicitation task, providing single-word terms to describe the audio quality of original and processed music samples; this was completed twice by each participant, once with hearing aids, and once without. Participants were then guided in discussing these raw terms across three focus groups, in which they reduced the term space, identified important perceptual groupings of terms, and developed perceptual attributes from these groups (including rating scales and definitions for each). Results: Findings show that there were seven key perceptual dimensions underlying music audio quality (clarity, harshness, distortion, spaciousness, treble strength, middle strength, and bass strength), alongside a music audio quality attribute and possible alternative frequency balance attributes. Discussion: We outline how these perceptual attributes align with extant literature, how attribute rating instruments might be used in future work, and the importance of better understanding the music listening difficulties of people with varied profiles of hearing loss
Further clinical and molecular delineation of the 15q24 microdeletion syndrome
Background Chromosome 15q24 microdeletion syndrome is a rare genomic disorder characterised by intellectual disability, growth retardation, unusual facial morphology and other anomalies. To date, 20 patients have been reported; 18 have had detailed breakpoint analysis. Aim To further delineate the features of the 15q24 microdeletion syndrome, the clinical and molecular characterisation of fifteen patients with deletions in the 15q24 region was performed, nearly doubling the number of reported patients. Methods Breakpoints were characterised using a custom, high-density array comparative hybridisation platform, and detailed phenotype information was collected for each patient. Results Nine distinct deletions with different breakpoints ranging in size from 266 kb to 3.75 Mb were identified. The majority of breakpoints lie within segmental duplication (SD) blocks. Low sequence identity and large intervals of unique sequence between SD blocks likely contribute to the rarity of 15q24 deletions, which occur 8-10 times less frequently than 1q21 or 15q13 microdeletions in our series. Two small, atypical deletions were identified within the region that help delineate the critical region for the core phenotype in the 15q24 microdeletion syndrome. Conclusion The molecular characterisation of these patients suggests that the core cognitive features of the 15q24 microdeletion syndrome, including developmental delays and severe speech problems, are largely due to deletion of genes in a 1.1-Mb critical region. However, genes just distal to the critical region also play an important role in cognition and in the development of characteristic facial features associated with 15q24 deletions. Clearly, deletions in the 15q24 region are variable in size and extent. Knowledge of the breakpoints and size of deletion combined with the natural history and medical problems of our patients provide insights that will inform management guidelines. Based on common phenotypic features, all patients with 15q24 microdeletions should receive a thorough neurodevelopmental evaluation, physical, occupational and speech therapies, and regular audiologic and ophthalmologic screenin
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