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Language and Reading Progress of Young Deaf and Hard-of-Hearing Children.
We examined the language and reading progress of 336 young DHH children in kindergarten, first and second grades. Trained assessors tested children's language, reading, and spoken and fingerspelled phonological awareness in the fall and spring of the school year. Children were divided into groups based on their auditory access and classroom communication: a spoken-only group (n = 101), a sign-only group (n = 131), and a bimodal group (n = 104). Overall, children showed delays in language and reading compared to norms established for hearing children. For language, vocabulary standard scores were higher than for English syntax. Although delayed in language, children made expected gains based on hearing norms from kindergarten to second grade. Reading scores declined from kindergarten to second grade. Spoken-only and bimodal children had similar word reading and reading comprehension abilities and higher scores than sign-only children. Spoken-only children had better spoken phonological awareness and nonword reading skills than the other two groups. The sign-only and bimodal groups made similar and significant gains in ASL syntax and fingerspelling phonological awareness
Depurated fish as an alternative reference for field-based biomarker monitoring
The whole of the Swan-Canning Estuary, in the south-west of Australia, is impacted by human activity, and the selection of a local reference site to assess the impact of environmental contamination on the health of biota is not possible. To determine whether fish depurated under laboratory conditions could be used as an alternative to a reference site; adult black bream (Acanthopagrus butcheri) were collected from the estuary and maintained in clean water (S24) for 3 months. A suite of biomarkers of fish health were assessed, and the results were compared with field-captured black bream from three sites within the estuary (Ascot, Claisebrook, and Riverton). Comparisons of a subset of biomarkers were also made between hatchery-bred juvenile fish and the depurated fish. Biomarker levels were up to 3.8 times higher in field captured fish compared with depurated fish, while DNA integrity was lower. EROD activity was comparable in the hatchery-bred black bream to the depurated fish while s-SDH levels were two times higher in the hatchery fish. From the results obtained, field-captured black bream depurated for 3 months are suitable to determine reference/baseline levels for biomarker of health studies in estuarine environments
Correspondence between solar fine-scale structures in the corona, transition region, and lower atmosphere from collaborative observations
The Soft X-Ray Imaging Payload and the High Resolution Telescope and Spectrograph (HRTS) instrument were launched from White Sands on 11 December 1987 in coordinated sounding rocket flights to investigate the correspondence of coronal and transition region structures, especially the relationship between X-ray bright points (XBPs) and transition region small spatial scale energetic events. The coaligned data from X-ray images are presented along with maps of sites of transition region energetic events observed in C IV (100,000 K), HRTS 1600 A spectroheliograms of the T sub min region and ground based magnetogram and He I 10830 A images
COVID-19 and EQ-5D-5L health state valuation
Background
We investigate whether and how general population health state values were influenced by the initial stages of the COVID-19 pandemic. Changes could have important implications, as general population values are used in health resource allocation.
Data
In Spring 2020, participants in a UK general population survey rated 2 EQ-5D-5L states, 11111 and 55555, as well as dead, using a visual analogue scale (VAS) from 100 = best imaginable health to 0 = worst imaginable health. Participants answered questions about their pandemic experiences, including COVID-19’s effect on their health and quality of life, and their subjective risk/worry about infection.
Analysis
VAS ratings for 55555 were transformed to the full health = 1, dead = 0 scale. Tobit models were used to analyse VAS responses, as well as multinomial propensity score matching (MNPS) to create samples balanced according to participant characteristics.
Results
Of 3021 respondents, 2599 were used for analysis. There were statistically significant, but complex associations between experiences of COVID-19 and VAS ratings. For example, in the MNPS analysis, greater subjective risk of infection implied higher VAS ratings for dead, yet worry about infection implied lower ratings. In the Tobit analysis, people whose health was affected by COVID-19 rated 55555 higher, whether the effect on health was positive or negative.
Conclusion
The results complement previous findings that the onset of the COVID-19 pandemic may have impacted EQ-5D-5L health state valuation, and different aspects of the pandemic had different effects
A Spatially Resolved `Inside-out' Outburst of IP Pegasi
We present a comprehensive photometric dataset taken over the entire outburst
of the eclipsing dwarf nova IP Peg in September/October 1997. Analysis of the
lightcurves taken over the long rise to the peak-of-outburst shows conclusively
that the outburst started near the centre of the disc and moved outwards. This
is the first dataset that spatially resolves such an outburst. The dataset is
consistent with the idea that long rise times are indicative of such
`inside-out' outbursts. We show how the thickness and the radius of the disc,
along with the mass transfer rate change over the whole outburst. In addition,
we show evidence of the secondary and the irradiation thereof. We discuss the
possibility of spiral shocks in the disc; however we find no conclusive
evidence of their existence in this dataset.Comment: 8 pages, 8 figures, to be appear in MNRA
Channel Interference in a Quasi Ballistic Aharonov-Bohm Experiment
New experiments are presented on the transmission of electron waves through a
2DEG (2 dimensional electron gas) ring with a gate on top of one of the
branches. Magnetoconductance oscillations are observed, and the phase of the
Aharanov-Bohm signal alternates between 0 and pi as the gate voltage is
scanned. A Fourier transform of the data reveals a dominant period in the
voltage which corresponds to the energy spacing between successive transverse
modes.A theoretical model including random phase shifts between successive
modes reproduces the essential features of the experiment.Comment: 4 pages, 6 Postscript figures, TEX, submitted to Physical Review
Letter
Genomic and physiological variability within Group II (non-proteolytic) Clostridium botulinum
BACKGROUND: Clostridium botulinum is a group of four physiologically and phylogenetically distinct bacteria that produce botulinum neurotoxin. While studies have characterised variability between strains of Group I (proteolytic) C. botulinum, the genetic and physiological variability and relationships between strains within Group II (non-proteolytic) C. botulinum are not well understood. In this study the genome of Group II strain C. botulinum Eklund 17B (NRP) was sequenced and used to construct a whole genome DNA microarray. This was used in a comparative genomic indexing study to compare the relatedness of 43 strains of Group II C. botulinum (14 type B, 24 type E and 5 type F). These results were compared with characteristics determined from physiological tests. RESULTS: Whole genome indexing showed that strains of Group II C. botulinum isolated from a wide variety of environments over more than 75 years clustered together indicating the genetic background of Group II C. botulinum is stable. Further analysis showed that strains forming type B or type F toxin are closely related with only toxin cluster genes targets being unique to either type. Strains producing type E toxin formed a separate subset. Carbohydrate fermentation tests supported the observation that type B and F strains form a separate subset to type E strains. All the type F strains and most of type B strains produced acid from amylopectin, amylose and glycogen whereas type E strains did not. However, these two subsets did not differ strongly in minimum growth temperature or maximum NaCl concentration for growth. No relationship was found between tellurite resistance and toxin type despite all the tested type B and type F strains carrying tehB, while the sequence was absent or diverged in all type E strains. CONCLUSIONS: Although Group II C. botulinum form a tight genetic group, genomic and physiological analysis indicates there are two distinct subsets within this group. All type B strains and type F strains are in one subset and all type E strains in the other
Periodic harmonic functions on lattices and points count in positive characteristic
This survey addresses pluri-periodic harmonic functions on lattices with
values in a positive characteristic field. We mention, as a motivation, the
game "Lights Out" following the work of Sutner, Goldwasser-Klostermeyer-Ware,
Barua-Ramakrishnan-Sarkar, Hunzikel-Machiavello-Park e.a.; see also 2 previous
author's preprints for a more detailed account. Our approach explores harmonic
analysis and algebraic geometry over a positive characteristic field. The
Fourier transform allows us to interpret pluri-periods of harmonic functions on
lattices as torsion multi-orders of points on the corresponding affine
algebraic variety.Comment: These are notes on 13p. based on a talk presented during the meeting
"Analysis on Graphs and Fractals", the Cardiff University, 29 May-2 June 2007
(a sattelite meeting of the programme "Analysis on Graphs and its
Applications" at the Isaac Newton Institute from 8 January to 29 June 2007
A first unbiased global NLO determination of parton distributions and their uncertainties
We present a determination of the parton distributions of the nucleon from a
global set of hard scattering data using the NNPDF methodology: NNPDF2.0.
Experimental data include deep-inelastic scattering with the combined HERA-I
dataset, fixed target Drell-Yan production, collider weak boson production and
inclusive jet production. Next-to-leading order QCD is used throughout without
resorting to K-factors. We present and utilize an improved fast algorithm for
the solution of evolution equations and the computation of general hadronic
processes. We introduce improved techniques for the training of the neural
networks which are used as parton parametrization, and we use a novel approach
for the proper treatment of normalization uncertainties. We assess
quantitatively the impact of individual datasets on PDFs. We find very good
consistency of all datasets with each other and with NLO QCD, with no evidence
of tension between datasets. Some PDF combinations relevant for LHC observables
turn out to be determined rather more accurately than in any other parton fit.Comment: 86 pages, 41 figures. PDF sets available from
http://sophia.ecm.ub.es/nnpdf/nnpdf_pdfsets.htm and from LHAPDF. Final
version to be published in Nucl. Phys. B. Various typos corrected and small
clarifications added, fig. 4 added, extended discussion of data consistency
especially in sect 5.1 and 5.
Integrating Multiple Biomarkers of Fish Health: A Case Study of Fish Health in Ports
Biomarkers of fish health are recognised as valuable biomonitoring tools that inform on the impact of pollution on biota. The integration of a suite of biomarkers in a statistical analysis that better illustrates the effects of exposure to xenobiotics on living organisms is most informative; however, most published ecotoxicological studies base the interpretation of results on individual biomarkers rather than on the information they carry as a set. To compare the interpretation of results from individual biomarkers with an interpretation based on multivariate analysis, a case study was selected where fish health was examined in two species of fish captured in two ports located in Western Australia. The suite of variables selected included chemical analysis of white muscle, body condition index, liver somatic index (LSI), hepatic ethoxyresorufin-O-deethylase activity, serum sorbitol dehydrogenase activity, biliary polycyclic aromatic hydrocarbon metabolites, oxidative DNA damage as measured by serum 8-oxo-dG, and stress protein HSP70 measured on gill tissue. Statistical analysis of individual biomarkers suggested little consistent evidence of the effects of contaminants on fish health. However, when biomarkers were integrated as a set by principal component analysis, there was evidence that the health status of fish in Fremantle port was compromised mainly due to increased LSI and greater oxidative DNA damage in fish captured within the port area relative to fish captured at a remote site. The conclusions achieved using the integrated set of biomarkers show the importance of viewing biomarkers of fish health as a set of variables rather than as isolated biomarkers of fish health
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