2,630 research outputs found
A modified version of the Bayley Scales of Infant Development-II for cognitive matching of infants with and without Down syndrome
Background Many measures of infants' early cognitive development, including the BSID-II (The Bayley Scales of Infant Development), mix together test items that assess a number of different developmental domains including language, attention, motor functioning and social abilities, and some items contribute to the assessment of more than one domain. Consequently, the scales may lead to under- or over-estimates of cognitive abilities in some clinical samples and may not be the best measure to use for matching purposes.
Method To address this issue we created a modified form of the BSID-II (the BSID-M) to provide a ‘purer’ assessment of the general cognitive capacities in infants with Down syndrome (DS) from 6 to 18 months of age. We excluded a number of items that implicated language, motor, attentional and social functioning from the original measure. This modified form was administered to 17 infants with Down syndrome when 6, 12 and 18 months old and to 41 typically developing infants at 4, 7 and 10 months old.
Results The results suggested that the modified form continued to provide a meaningful and stable measure of cognitive functioning and revealed that DS infants may score marginally higher in terms of general cognitive abilities when using this modified form than they might when using the standard BSID-II scales.
Conclusions This modified form may be useful for researchers who need a ‘purer’ measure with which to match infants with DS and other infants with intellectual disabilities on cognitive functioning
Transformation of Algebraic Specifications into Ontological Semantic Descriptions of Web Services
The accurate description of service semantics plays a crucial role in service discovery, composition and interaction. Most work in this area has been focused on ontological descriptions, which are searchable and machineunderstandable.
However, they do not define service functionality in a verifiable and testable manner In contrast, formal specification techniques, having evolved over the past 30 years, can define semantics in such a manner, but they have not yet been widely applied to service computing because the specifications produced are not searchable. There is a huge gap between these two methods of semantics description. This paper bridges the gap by advancing a transformation technique. It specifies services formally in an algebraic specification language, and then, extracts an ontological description of domain knowledge and service semantics as profiles in an ontology description language such as OWL-S. This brings the desired searchability benefits. The paper presents a prototype tool for performing this transformation and reports a case study to demonstrate the feasibility of our approach
Capturing complexity: field-testing the use of ‘structure from motion’ derived virtual models to replicate standard measures of reef physical structure
Reef structural complexity provides important refuge habitat for a range of marine organisms, and is a useful indicator of the health and resilience of reefs as a whole. Marine scientists have recently begun to use ‘Structure from Motion’ (SfM) photogrammetry in order to accurately and repeatably capture the 3D structure of physical objects underwater, including reefs. There has however been limited research on the comparability of this new method with existing analogue methods already used widely for measuring and monitoring 3D structure, such as ‘tape and chain rugosity index (RI)’ and graded visual assessments. Our findings show that analogue and SfM RI can be reliably converted over a standard 10-m reef section (SfM RI = 1.348 × chain RI—0.359, r^{2} = 0.82; and Chain RI = 0.606 × SfM RI + 0.465) for RI values up to 2.0; however, SfM RI values above this number become increasingly divergent from traditional tape and chain measurements. Additionally, we found SfM RI correlates well with visual assessment grades of coral reefs over a 10 × 10 m area (SfM RI = 0.1461 × visual grade + 1.117; r^{2} = 0.83). The SfM method is shown to be affordable and non-destructive whilst also allowing the data collected to be archival, less biased by the observer, and broader in its scope of applications than standard methods. This work allows researchers to easily transition from analogue to digital structural assessment techniques, facilitating continued long-term monitoring, whilst also improving the quality and additional research value of the data collected
Measuring and Correcting Wind-Induced Pointing Errors of the Green Bank Telescope Using an Optical Quadrant Detector
Wind-induced pointing errors are a serious concern for large-aperture
high-frequency radio telescopes. In this paper, we describe the implementation
of an optical quadrant detector instrument that can detect and provide a
correction signal for wind-induced pointing errors on the 100m diameter Green
Bank Telescope (GBT). The instrument was calibrated using a combination of
astronomical measurements and metrology. We find that the main wind-induced
pointing errors on time scales of minutes are caused by the feedarm being blown
along the direction of the wind vector. We also find that wind-induced
structural excitation is virtually non-existent. We have implemented offline
software to apply pointing corrections to the data from imaging instruments
such as the MUSTANG 3.3 mm bolometer array, which can recover ~70% of
sensitivity lost due to wind-induced pointing errors. We have also performed
preliminary tests that show great promise for correcting these pointing errors
in real-time using the telescope's subreflector servo system in combination
with the quadrant detector signal.Comment: 17 pages, 11 figures; accepted for publication in PAS
Emotional engagements predict and enhance social cognition in young chimpanzees
Social cognition in infancy is evident in coordinated triadic engagements, that is, infants attending jointly with social partners and objects. Current evolutionary theories of primate social cognition tend to highlight species differences in cognition based on human-unique cooperative motives. We consider a developmental model in which engagement experiences produce differential outcomes. We conducted a 10-year-long study in which two groups of laboratory-raised chimpanzee infants were given quantifiably different engagement experiences. Joint attention, cooperativeness, affect, and different levels of cognition were measured in 5- to 12-month-old chimpanzees, and compared to outcomes derived from a normative human database. We found that joint attention skills significantly improved across development for all infants, but by 12 months, the humans significantly surpassed the chimpanzees. We found that cooperativeness was stable in the humans, but by 12 months, the chimpanzee group given enriched engagement experiences significantly surpassed the humans. Past engagement experiences and concurrent affect were significant unique predictors of both joint attention and cooperativeness in 5- to 12-month-old chimpanzees. When engagement experiences and concurrent affect were statistically controlled, joint attention and cooperation were not associated. We explain differential social cognition outcomes in terms of the significant influences of previous engagement experiences and affect, in addition to cognition. Our study highlights developmental processes that underpin the emergence of social cognition in support of evolutionary continuity
Biochemical enrichment and biophysical characterization of a taste receptor for L-arginine from the catfish, Ictalurus puntatus
BACKGROUND: The channel catfish, Ictalurus punctatus, is invested with a high density of cutaneous taste receptors, particularly on the barbel appendages. Many of these receptors are sensitive to selected amino acids, one of these being a receptor for L-arginine (L-Arg). Previous neurophysiological and biophysical studies suggested that this taste receptor is coupled directly to a cation channel and behaves as a ligand-gated ion channel receptor (LGICR). Earlier studies demonstrated that two lectins, Ricinus communis agglutinin I (RCA-I) and Phaseolus vulgaris Erythroagglutinin (PHA-E), inhibited the binding of L-Arg to its presumed receptor sites, and that PHA-E inhibited the L-Arg-stimulated ion conductance of barbel membranes reconstituted into lipid bilayers. RESULTS: Both PHA-E and RCA-I almost exclusively labeled an 82–84 kDa protein band of an SDS-PAGE of solubilized barbel taste epithelial membranes. Further, both rhodamine-conjugated RCA-I and polyclonal antibodies raised to the 82–84 kDa electroeluted peptides labeled the apical region of catfish taste buds. Because of the specificity shown by RCA-I, lectin affinity was chosen as the first of a three-step procedure designed to enrich the presumed LGICR for L-Arg. Purified and CHAPS-solubilized taste epithelial membrane proteins were subjected successively to (1), lectin (RCA-I) affinity; (2), gel filtration (Sephacryl S-300HR); and (3), ion exchange chromatography. All fractions from each chromatography step were evaluated for L-Arg-induced ion channel activity by reconstituting each fraction into a lipid bilayer. Active fractions demonstrated L-Arg-induced channel activity that was inhibited by D-arginine (D-Arg) with kinetics nearly identical to those reported earlier for L-Arg-stimulated ion channels of native barbel membranes reconstituted into lipid bilayers. After the final enrichment step, SDS-PAGE of the active ion channel protein fraction revealed a single band at 82–84 kDa which may be interpreted as a component of a multimeric receptor/channel complex. CONCLUSIONS: The data are consistent with the supposition that the L-Arg receptor is a LGICR. This taste receptor remains active during biochemical enrichment procedures. This is the first report of enrichment of an active LGICR from the taste system of vertebrata
A monodisperse transmembrane α-helical peptide barrel
The fabrication of monodisperse transmembrane barrels formed from short synthetic peptides has not been demonstrated previously. This is in part because of the complexity of the interactions between peptides and lipids within the hydrophobic environment of a membrane. Here we report the formation of a transmembrane pore through the self-assembly of 35 amino acid α-helical peptides. The design of the peptides is based on the C-terminal D4 domain of the Escherichia coli polysaccharide transporter Wza. By using single-channel current recording, we define discrete assembly intermediates and show that the pore is most probably a helix barrel that contains eight D4 peptides arranged in parallel. We also show that the peptide pore is functional and capable of conducting ions and binding blockers. Such α-helix barrels engineered from peptides could find applications in nanopore technologies such as single-molecule sensing and nucleic-acid sequencing
Educational outcomes in extremely preterm children : neuropsychological correlates and predictors of attainment
This study assessed the impact of extremely preterm birth on academic attainment at 11 years of
age, investigated neuropsychological antecedents of attainment in reading and mathematics, and
examined early predictors of educational outcomes. Children born extremely preterm had significantly
poorer academic attainment and a higher prevalence of learning difficulties than their term
peers. General cognitive ability and specific deficits in visuospatial skills or phoneme deletion at 6
years were predictive of mathematics and reading attainment at 11 years in both extremely preterm
and term children. Phonological processing, attention, and executive functions at 6 years were also
associated with academic attainment in children born extremely preterm. Furthermore, social factors,
neonatal factors (necrotizing enterocolitis, breech delivery, abnormal cerebral ultrasound, early
breast milk provision), and developmental factors at 30 months (head circumference, cognitive development),
were independent predictors of educational outcomes at 11 years. Neonatal complications
combined with assessments of early cognitive function provide moderate prediction for educational
outcomes in children born extremely preterm
CIDE: An Integrated Development Environment for Microservices
Microservices is a flexible architectural style that has many advantages over the alternative monolithic style. These include better performance and scalability. It is particularly suitable, and widely adopted, for cloud-based applications, because in this architecture a software system consisting of a large suite of services of fine granularity, each running its own process and communicating with the others. However, programming such systems is more complex. In this paper we report on CIDE, an integrated software development environment that helps with this. CIDE supports programming in a novel agent-oriented language called CAOPLE and tests their execution in a cluster environment. We present the architecture of CIDE, discuss its design based on the principles of the DevOps software development methodology, and describe facilities that support continuous testing and seamless integration, two other advantages of Microservices
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