8,343 research outputs found
Method of making a cermet Patent
Cermet for nuclear fuel constructed by pressing metal coated ceramic particles in die at temperature to cause bonding of metal coatings, and tested for thermal stabilit
Motor and executive function at 6 years of age after extremely preterm birth
BACKGROUND. Studies of very preterm infants have demonstrated impairments in multiple neurocognitive domains. We hypothesized that neuromotor and executive-
function deficits may independently contribute to school failure.
METHODS.We studied children who were born at 25 completed weeksâ gestation in the United Kingdom and Ireland in 1995 at early school age. Children underwent
standardized cognitive and neuromotor assessments, including the Kaufman Assessment Battery for Children and NEPSY, and a teacher-based assessment of academic achievement.
RESULTS. Of 308 surviving children, 241 (78%) were assessed at a median age of 6 years 4 months. Compared with 160 term classmates, 180 extremely preterm children without cerebral palsy and attending mainstream school performed less
well on 3 simple motor tasks: posting coins, heel walking, and 1-leg standing. They more frequently had nonâright-hand preferences (28% vs 10%) and more associated/
overflow movements during motor tasks. Standardized scores for visuospatial and sensorimotor function performance differed from classmates by 1.6 and 1.1 SDs of the classmatesâ scores, respectively. These differences attenuated but remained significant after controlling for overall cognitive scores. Cognitive, visuospatial
scores, and motor scores explained 54% of the variance in teachersâ ratings of performance in the whole set; in the extremely preterm group, additional variance was explained by attention-executive tasks and gender.
CONCLUSIONS. Impairment of motor, visuospatial, and sensorimotor function, including planning, self-regulation, inhibition, and motor persistence, contributes excess
morbidity over cognitive impairment in extremely preterm children and contributes independently to poor classroom performance at 6 years of age
The EPICure study : growth and blood pressure at 6 years of age following extremely preterm birth
Background: Preterm children are at risk for reduced growth in early childhood, which may predispose them to later changes in blood pressure. We studied growth and blood pressure (BP) in extremely preterm (EP) children at age 6 years.
Methods: We evaluated children who were born at 25 completed weeks of gestation or less in the United Kingdom and Ireland in 1995 when they reached early school age. Children underwent standardized assessments, including auxology and sitting blood pressure.
Results: Of 308 surviving children, 241 (78 percent) were assessed at a median age of 6 years 4 months; 160 full term classmates acted as a comparison group. Compared to classmates, EP children were 1.2 standard deviations (SD) lighter, 0.97SD shorter, BMI was 0.95SD lower and head circumference 1.3SD lower. Compared to 2.5 years of age, EP children showed catch up in terms of weight by 0.37SD, height by 0.42SD and head circumference by 0.13SD. Systolic
and diastolic BP were lower by 2.3mmHg and 2.4mmHg respectively in EP children but these differences were accounted for by differences in height and BMI. Maternal smoking in pregnancy was associated with lower BP, children born before 24 weeks had higher systolic and children given postnatal steroids higher diastolic pressures.
Conclusions: Poor postnatal growth seen after birth and at in the third year persists into school age. Catch up growth reduces some of the early deficit but is least for head growth.
Despite serious postnatal growth restriction blood pressure appears similar in both EP and term classmates
A framework for event detection in field-sports video broadcasts based on SVM generated audio-visual feature model. Case-study: soccer video
In this paper we propose a novel audio-visual feature-based framework, for event detection in field sports broadcast video. The system is evaluated via a case-study involving MPEG encoded soccer video. Specifically, the evidence gathered by various feature detectors is combined by means of a learning algorithm (a support vector machine), which infers the occurrence of an event, based on a model generated during a training phase, utilizing a corpus of 25 hours of content. The system is evaluated using 25 hours of separate test content. Following an evaluation of results obtained, it is shown for this case, that both high precision and recall statistics are achievable
Audio processing for automatic TV sports program highlights detection
In todayâs fast paced world, the time available to watch
long sports programmes is decreasing, while the number of sports channels is rapidly increasing. Many viewers desire the facility to watch just the highlights of sports events.
This paper presents a simple, but effective, method for generating sports video highlights summaries. Our method detects semantically important events in sports programmes by using the Scale Factors in the MPEG audio bitstream to generate an audio amplitude profile of the program. The Scale Factors for the subbands corresponding to the voice bandwidth give a strong indication of the level of commentator and/or spectator excitement. When periods of sustained high audio amplitude have been detected and ranked, the corresponding video shots may be concatenated to produce a summary of the program highlights. Our method uses only the Scale Factor information that is directly accessible from the MPEG bitstream, without any decoding, leading to highly efficient computation. It is also rather more generic than many existing techniques, being particularly suitable for the more popular sports televised in Ireland such as soccer, Gaelic football, hurling, rugby, horse racing and motor racing
Two Point Resolution of a Defocused Multi-Aperture System Eyelet
Multi-aperture optical systems based on the insect eye offer an alternative to the common optical system based on the human eye. Some of the advantages of a multi - aperture system include the ability to perform parallel processing, have super resolution and have available large amounts of system redundancy.
An individual eyelet of a multi-aperture system consists of a gradient index lens coupled to optical fibers which transfer the incident light on the lens to individual detectors.
A mathematical model of an individual eyelet was developed. It is a flexible model allowing various system parameters to vary. Computer based algorithms were developed to locate and resolve two points in space. The model was exercised with experimental data and found to have a resolution of 3.1°. The algorithm was also exercised with the computer model and the results compared favorably
Acclimatization physiology in tissue cultured plants
Physiological and morphological aspects of acclimatization were studied in
cultured tomato (Lycopersicon esculentum Mill.), banana (Musa accuminata L.)
and date palm (Phoenix dactyli/era ). The nutrient availability from agar solidified
culture medium was determined to establish the nutrient status of the cultured
plandets before transfer to ex vitro conditions. Analysis of the plant tissues
demonstrated decreasing tissue concentrations of the major elements nitrogen,
phosphorus and potassium with decreasing concentration of basal salts in the
medium. The effects of agar and increasing sodium concentration in the culture
medium was studied in cultured banana plants. Plandets grown on agar solidified
medium with increased levels of sodium, exhibited reduced growth and stomatal
movement. The use of agar as a solidifying agent was shown to reduce root
growth, development and stomatal functioning in these plants.
The efficiency of ion and water uptake, and translocation in in vitro and
acclimatized tomato plants was assessed using [32P]-orthophosphate and [3H]_
tritiated water. The functional capacity of the root system fOlmed in vitro was
established, and assessed following acclimatization treatments at 40% and 80%
relative humidity. Comparative studies with tomato seedlings demonstrated reduced
efficiency of ion translocation to the shoot in plandets growing in vitro. However,
transport to the shoot improved during acclimatization. Ion absorption studies on
in vitro and acclimatized palm plants demonstrated phosphate uptake and
translocation in both plant types.
A detailed examination of the tissue structure through the root/shoot junction and
roots of · cultured, acclimatized and seedling tomato plants illustrated differences in
the vascular development between the three plant types. However, no major
abnormalities were observed which could have accounted for the reduced
translocation efficiency in the cultured plants. Increased vascularization present in
the root/shoot junction of the cultured plants may increase resistance to the
transpiration flow through the region. The type of root system produced in vitro
and the root/shoot ratio was manipulated using varying IAA and sucrose
treatments. Improved root development and plantlet survival rates were achieved
by reduced exposure to IAA during the root initiation phase followed by root
elongation on IAA free medium supplemented with sucrose. Acclimatization at
low relative humidity (40%) was achieved by producing plandets with balanced
root/shoot ratios and a well developed root system
NICMOS and VLBA observations of the gravitational lens system B1933+503
NICMOS observations of the complex gravitational lens system B1933+503 reveal
infrared counterparts to two of the inverted spectrum radio images. The
infrared images have arc-like structures. The corresponding radio images are
also detected in a VLBA map made at 1.7 GHz with a resolution of 6 mas. We fail
to detect two of the four inverted radio spectrum components with the VLBA even
though they are clearly visible in a MERLIN map at the same frequency at a
different epoch. The absence of these two components could be due to rapid
variability on a time-scale less than the time delay, or to broadening of the
images during propagation of the radio waves through the ISM of the lensing
galaxy to an extent that they fall below the surface brightness detectability
threshold of the VLBA observations. The failure to detect the same two images
with NICMOS is probably due to extinction in the ISM of the lensing galaxy.Comment: 5 pages, 4 figures, submitted to MNRA
Audio and video processing for automatic TV advertisement detection
As a partner in the Centre for Digital Video Processing, the Visual Media Processing Group at Dublin City University conducts research and development in the area of digital video management. The current stage of development is demonstrated on our Web-based digital video system called FĂschlĂĄr [1,2], which provides for efficient recording,
analyzing, browsing and viewing of digitally captured television programmes. In order to make the browsing of
programme material more efficient, users have requested the option of automatically deleting advertisement breaks.
Our initial work on this task focused on locating ad-breaks by detecting patterns of silent black frames which separate
individual advertisements and/or complete ad-breaks in most commercial TV stations. However, not all TV stations use
silent, black frames to flag ad-breaks. We therefore decided to attempt to detect advertisements using the rate of shot cuts in the digitised TV signal. This paper describes the implementation and performance of both methods of ad-break
detection
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