290 research outputs found
Deriving accurate peculiar velocities (even at high redshift)
The way that peculiar velocities are often inferred from measurements of
distances and redshifts makes an approximation, v_p = cz-H_0 D, that gives
significant errors even at relatively low redshifts (overestimates peculiar
velocity by ~ 100 km/s at z~0.04). Here we demonstrate where the approximation
breaks down, the systematic offset it introduces, and how the exact calculation
should be implemented.Comment: 6 pages, 4 figures, accepted by MNRAS; revision adds footnote 3, a
couple of references, and some minor tweaks to tex
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Factors affecting reading comprehension in primary pupils
This thesis addresses the problem of 8-11 year old pupils who, although appearing to read text fluently, frequently misunderstand it. This problem was studied through Scottish school-based research using classroom materials and subjects from natural class groups. Data were collected from language assignments in daily work programmes, with response material in either written or illustrated form. Nine feasibility studies and a main study involving eighty subjects were carried out.
The effects of five variables, text, presentation mode, age, ability and geographic location, on the totals and types of miscomprehensions displayed by the subjects in directed and free-recall comprehension tasks were calculated. 'Errors' are considered to be divergences from the author's supposed meaning. It is found that the collected errors are not random but may be classified into groups. Ten types of error were identified as regularly occurring and the category system developed was validated by teachers and others involved in the field of education.
The effects of the five variables on the numbers and categories of error collected and the interactions between these variables were subjected to statistical analysis. Text and presentation mode are found to be the factors having most effect on the quantity and type of error produced. This finding is at variance with the generally accepted assumption that age, ability and possibly environment are determinants of potential pupil achievement. Miscomprehensions are discovered to be widely distributed across the ability range but they may be concealed by pupils in their pursuit of acceptable responses. The progress expected with increasing age is not always evident.
The value of the category system as a teaching tool in comprehension development across the curriculum and pupil age range is assessed and suggestions given for its use. Implications of the findings for pupil assessment procedures and classroom practice are also discussed
Exploring accounts of joint working between Speech and Language Therapists and Stroke Association Communication Support Coordinators
Exploring accounts of joint working between Speech and Language Therapists and Stroke Association Communication Support Coordinators
Introduction
Both Speech and Language Therapists (SLTs) and Stroke Association Communication Support Coordinators (CSCs) are employed across the UK to provide services for people with communication difficulties following Stroke. The two roles are usually employed by different sectors and are subject to very different levels of qualification and professional regulation. Despite recommendations that the two roles work together, there is little existing literature examining current practices of joint working between SLTs and CSCs.
Method
Data were collected through a series of in depth individual interviews with five CSCs and seven SLTs working within the East of England. Data were analysed inductively using Thematic Analysis (Braun & Clark, 2006).
Results
Six themes were developed which highlighted the perceived benefits and challenges in this example of cross sector working. Both SLTs and CSCs identified strong incentives for joint working. The themes developed suggested a number of processes are engaged in negotiating the joint working relationship. These include ‘Developing and earning trust and respect’; ‘Pushing to establish place’; and ‘Struggling against external pressures and threats’. In addition, two further themes were developed to explore the process of finding agreement in the division of workload: ‘Sharing Out’ of aphasia; and ‘Local level Negotiation and Matching of expectations’.
Conclusions:
The findings suggest a number of unique features which characterise joint working relationships between SLTs and CSCs. Clinical applications based on the findings are discussed, along with suggested areas for further research
Metabolically active cytochrome P450 CYP1B1 in solid tumours: a novel target for chemotherapeutic intervention.
Cytochrome P450 CYP1B1 is a member of a superfamily of haemoproteins that are central to the oxidative metabolism of a wide variety of endogenous and exogenous compounds. Several of these enzymes have an established role in the metabolic bio-transformation of a variety of anti-cancer drugs. In this study, we demonstrated both CYP1B1 and CPR activity in the microsomal fraction of ovarian and kidney tumours
The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity
We have made the largest volume measurement to date of the transition to large-scale homogeneity in the distribution of galaxies. We use the WiggleZ survey, a spectroscopic survey of over 200 000 blue galaxies in a cosmic volume of ∼1 h^(−3) Gpc^3. A new method of defining the ‘homogeneity scale' is presented, which is more robust than methods previously used in the literature, and which can be easily compared between different surveys. Due to the large cosmic depth of WiggleZ (up to z = 1), we are able to make the first measurement of the transition to homogeneity over a range of cosmic epochs. The mean number of galaxies N(< r) in spheres of comoving radius r is proportional to r^3 within 1 per cent, or equivalently the fractal dimension of the sample is within 1 per cent of D_2 = 3, at radii larger than 71 ± 8 h^(−1) Mpc at z ∼ 0.2, 70 ± 5 h^(−1) Mpc at z ∼ 0.4, 81 ± 5 h^(−1) Mpc at z ∼ 0.6 and 75 ± 4 h^(−1) Mpc at z ∼ 0.8. We demonstrate the robustness of our results against selection function effects, using a Λ cold dark matter (ΛCDM) N-body simulation and a suite of inhomogeneous fractal distributions. The results are in excellent agreement with both the ΛCDM N-body simulation and an analytical ΛCDM prediction. We can exclude a fractal distribution with fractal dimension below D_2 = 2.97 on scales from ∼80 h^(−1) Mpc up to the largest scales probed by our measurement, ∼300 h^(−1) Mpc, at 99.99 per cent confidence
Exploring regulatory networks of miR-96 in the developing inner ear.
Mutations in the microRNA Mir96 cause deafness in mice and humans. In the diminuendo mouse, which carries a single base pair change in the seed region of miR-96, the sensory hair cells crucial for hearing fail to develop fully and retain immature characteristics, suggesting that miR-96 is important for coordinating hair cell maturation. Our previous transcriptional analyses show that many genes are misregulated in the diminuendo inner ear and we report here further misregulated genes. We have chosen three complementary approaches to explore potential networks controlled by miR-96 using these transcriptional data. Firstly, we used regulatory interactions manually curated from the literature to construct a regulatory network incorporating our transcriptional data. Secondly, we built a protein-protein interaction network using the InnateDB database. Thirdly, gene set enrichment analysis was used to identify gene sets in which the misregulated genes are enriched. We have identified several candidates for mediating some of the expression changes caused by the diminuendo mutation, including Fos, Myc, Trp53 and Nr3c1, and confirmed our prediction that Fos is downregulated in diminuendo homozygotes. Understanding the pathways regulated by miR-96 could lead to potential therapeutic targets for treating hearing loss due to perturbation of any component of the network
The WiggleZ Dark Energy Survey: the transition to large-scale cosmic homogeneity
We have made the largest-volume measurement to date of the transition to
large-scale homogeneity in the distribution of galaxies. We use the WiggleZ
survey, a spectroscopic survey of over 200,000 blue galaxies in a cosmic volume
of ~1 (Gpc/h)^3. A new method of defining the 'homogeneity scale' is presented,
which is more robust than methods previously used in the literature, and which
can be easily compared between different surveys. Due to the large cosmic depth
of WiggleZ (up to z=1) we are able to make the first measurement of the
transition to homogeneity over a range of cosmic epochs. The mean number of
galaxies N(<r) in spheres of comoving radius r is proportional to r^3 within
1%, or equivalently the fractal dimension of the sample is within 1% of D_2=3,
at radii larger than 71 \pm 8 Mpc/h at z~0.2, 70 \pm 5 Mpc/h at z~0.4, 81 \pm 5
Mpc/h at z~0.6, and 75 \pm 4 Mpc/h at z~0.8. We demonstrate the robustness of
our results against selection function effects, using a LCDM N-body simulation
and a suite of inhomogeneous fractal distributions. The results are in
excellent agreement with both the LCDM N-body simulation and an analytical LCDM
prediction. We can exclude a fractal distribution with fractal dimension below
D_2=2.97 on scales from ~80 Mpc/h up to the largest scales probed by our
measurement, ~300 Mpc/h, at 99.99% confidence.Comment: 21 pages, 16 figures, accepted for publication in MNRA
SMARCB1 loss induces druggable cyclin D1 deficiency via upregulation of MIR17HG in atypical teratoid rhabdoid tumors
Atypical teratoid rhabdoid tumor (ATRT) is a fatal pediatric malignancy of the central neural system lacking effective treatment options. It belongs to the rhabdoid tumor family and is usually caused by biallelic inactivation of SMARCB1, encoding a key subunit of SWI/SNF chromatin remodeling complexes. Previous studies proposed that SMARCB1 loss drives rhabdoid tumor by promoting cell cycle through activating transcription of cyclin D1 while suppressing p16. However, low cyclin D1 protein expression is observed in most ATRT patient tumors. The underlying mechanism and therapeutic implication of this molecular trait remain unknown. Here, we show that SMARCB1 loss in ATRT leads to the reduction of cyclin D1 expression by upregulating MIR17HG, a microRNA (miRNA) cluster known to generate multiple miRNAs targeting CCND1. Furthermore, we find that this cyclin D1 deficiency in ATRT results in marked in vitro and in vivo sensitivity to the CDK4/6 inhibitor palbociclib as a single agent. Our study identifies a novel genetic interaction between SMARCB1 and MIR17HG in regulating cyclin D1 in ATRT and suggests a rationale to treat ATRT patients with FDA- approved CDK4/6 inhibitors. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156416/2/path5493.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156416/1/path5493_am.pd
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