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Nuclear Energy Research Initiative Project No. 02 103 Innovative Low Cost Approaches to Automating QA/QC of Fuel Particle Production Using On Line Nondestructive Methods for Higher Reliability Final Project Report
This Nuclear Energy Research Initiative (NERI) project was tasked with exploring, adapting, developing and demonstrating innovative nondestructive test methods to automate nuclear coated particle fuel inspection so as to provide the United States (US) with necessary improved and economical Quality Assurance and Control (QA/QC) that is needed for the fuels for several reactor concepts being proposed for both near term deployment [DOE NE & NERAC, 2001] and Generation IV nuclear systems. Replacing present day QA/QC methods, done manually and in many cases destructively, with higher speed automated nondestructive methods will make fuel production for advanced reactors economically feasible. For successful deployment of next generation reactors that employ particle fuels, or fuels in the form of pebbles based on particles, extremely large numbers of fuel particles will require inspection at throughput rates that do not significantly impact the proposed manufacturing processes. The focus of the project is nondestructive examination (NDE) technologies that can be automated for production speeds and make either: (I) On Process Measurements or (II) In Line Measurements. The inspection technologies selected will enable particle “quality” qualification as a particle or group of particles passes a sensor. A multiple attribute dependent signature will be measured and used for qualification or process control decisions. A primary task for achieving this objective is to establish standard signatures for both good/acceptable particles and the most problematic types of defects using several nondestructive methods
A ring system detected around the Centaur (10199) Chariklo
Until now, rings have been detected in the Solar System exclusively around the four giant planets. Here we report the discovery of the rst minor-body ring system around the Centaur object (10199) Chariklo, a body with equivalent radius 124±9 km. A multi-chord stellar occultation revealed the presence of two dense rings around Chariklo, with widths of about 7 km and 3 km, optical depths 0.4 and 0.06, and orbital radii 391 and 405 km, respectively. The present orientation of the ring is consistent with an edge-on geometry in 2008, thus providing a simple explanation for the dimming of Chariklo's system between 1997 and 2008, and for the gradual disappearance of ice and other absorption features in its spectrum over the same period. This implies that the rings are partially composed of water ice. These rings may be the remnants of a debris disk, which were possibly con ned by embedded kilometre-sized satellites
How predatory mites cope with the web of their tetranychid prey: a functional view on dorsal chaetotaxy in the Phytoseiidae
Comportement alimentaire d'Euseius stipulatus et Typhlodromus phialatus sur l'acarien rouge de l'oranger Panonychus citri [Acari: Phytoseffdae, Tetranychidae]
[EN] Observations were made on the feeding behavior of the two main phytoseiid species in Spanish Citrus orchards,Euseius stipulatus (Athias-Henriot) andTyphlodromus phialatus Athias-henriot. The experiences were carried out by rearing the predatory mites on excised orange leaves, and always with an excess of the prey the Citrus Red Mite (=CRM)Panonychus citri (McGregor). In experiments with all stages of CRM, the number of prey killed per hour was 5.12 and 2.00, the percentage of successful attacks, 58% and 21%, and the mean time spent feeding on each prey was 5.1 and 12.2 minutes for starving females ofE. stipulatus andT. phialatus respectively.E. stipulatus feeds on all stages of the prey except eggs, andT. philatus, on all stages, except males. Both species attack much less successfully females ofP. citri rather than immatures. In experiments with adult females and eggs ofP. citri as prey, the mean number of prey killed daily was 4.51 females forE. stipulatus, and 2.01 females and 2.12 eggs forT. philatus. Considering this killing rate and the number of eggs laid by the predators in the same period, it can be concluded thatE. stipulatus consumes only 30% of the content of the preys killed, whereasT. philatus consumes a percentage of prey variable between individuals and ranging from 40% to 100%. These differences in feeding behavior between the two species could partly explain differences in their efficiency as biocontrol agents ofP. citri observed in the field.[FR] On a étudié le comportement alimentaire des deux principales espèces de phytoséiides présents dans les vergers de Citrus en Espagne,Euseius stipulatus (Athias-Henriot) etTyphlodromus phialatus Athias-Henriot. Les expériences ont été menées en élevant l'acarien prédateur sur feuilles d'oranger, avec un excès de sa proiePanonychus citri (McGregor). Dans les essais avec tous les stades de l'acarien rouge, le nombre moyen de proies tuées par heure est de 5.12 et 2.00, le pourcentage d'attaques réussies de 58% et 21% et le temps moyen passé à se nourrir sur chaque proie de 5.1 min et 12.2 min respectivement pour les femelles d'E. stipulatus etT. phialatus.
Tous les stades de développement, excepté le stade œuf, peuvent être consommés parE. stipulatus tandis queT. phialatus se nourrit de tous les stades, à l'exception des mes. Chez les deux espèces, les femelles deP. citri sont attaquées avec moins de succès que les immatures.
Lorsque les proies sont constituées de femelles adultes ou d'œufs deP. citri le nombre moyen de proies tuées quotidiennement est de 4.51 femelles pourE. stipulatus, et de 2.01 femelles et 2.12 œufs pourT. phialatus.
Si l'on considère le nombre d'Ĺ“ufs pondus par les acariens prĂ©dateurs durant la mĂŞme pĂ©riode,E. stipulatus ingère seulement 30% du total des proies tuĂ©es, alors queT. phialatus ingère un nombre de proies variable selon les individus, allant de 40 Ă 100%. Ces diffĂ©rences d'alimentation chez ces deux espèces pourraient expliquer en partie leurs diffĂ©rences d'efficacitĂ© observĂ©es sur le terrain, en tant qu'agents de lutte biologique.This work was funded by a grant from Comision Asesora de InvestigaciĂłn Cientifica y TĂ©cnica (0577/81).Ferragut PĂ©rez, FJ.; Laborda Cenjor, R.; Costa Comelles, J.; GarcĂa Mari, F. (1992). Feeding behavior of Euseius stipulatus and Typhlodromus phialatus on the Citrus Red Mite Panonychus citri (Acari: Phytoseiidae, Tetranychidae). ENTOMOPHAGA. 37(4):537-543. https://doi.org/10.1007/BF02372323S537543374Badii, M. H. andMcMurtry, J. A. — 1984. Feeding behavior of some phytoseiid predators on the broad mitePolyphagotarsonemus latus (Acari: Phytoseiidae: Tarsonemidae). —Entomophaga, 29, 49–53.Blommers, L., Lobbes, P., Vink, P. andWegdam, F. — 1977. Studies on the response ofAmblyseius bibens (Acarina: Phytoseiidae) to conditions to prey scarcity. —Entomophaga, 22: 247–258.De Moraes, G. J. andMcMurtry, J. A. — 1981. Biology ofAmblyseius citrifolius (Denmark and Muma) (Acarina: Phytoseiidae). —Hilgardia, 49: 1–29.Ferragut, F., GarcĂa-MarĂ, F., Costa-Comelles, J. andLaborda, R. — 1987. Influence of food and temperature on development and oviposition ofEuseius stipulatus (Athias-Henriot) andTyphlodromus phialatus Athias-Henriot (Acari: Phytoseiidae). —Exp. Appl. Acarol., 3: 317–329.Friese, D. D. andGilstrap, F. E. — 1982. Influence of prey availability on reproduction and prey consumption ofPhytoseiulus persimilis, Amblyseius californicus andMetaseiulus occidentalis (Acarina: Phytoseiidae). —Internat. J. Acarol., vol. 8, n0 2: 85–89.GarcĂa-MarĂ, F., Ferragut, F., Marzal, C., Costa-Comelles, J. andLaborda, R. — 1986. Acaros que viven en las hojas de los citricos españoles. —Inv. Agr. Prod. Prot. Vegetal, vol. 1 (2): 61–92.Hoyt, S. C. — 1970. Effect of short feeding periods byMetaseiulus occidentalis on fecundity and mortality ofTetranychus mcdanieli. —Ann. Entomol. Soc. Am., 63: 1382–1384.Sabelis, M. W. — 1985. Predation on spider mites. In Spider Mites. Their Biology, Natural Enemies and Control. (Helle andSabelis ed.). — Elsevier, Amsterdam Vol. 1B, pp. 103–129.Sandness, J. N. andMcMurtry, J. A. — 1970. Functional response of three species of Phytoseiidae (Acarina) to prey density.Can. Ent., 102: 692–704.Sandness, J. N. andMcMurtry, J. A. — 1972. Prey consumption behavior ofAmblyseius largoensis in relation to hunger. —Can. Ent., 104: 461–470.Tanigoshi, L. K. — 1981. Advances in knowledge of the biology of the Phytoseiidae.In: Recent advances in knowledge of the Phytoseiidae (M. A. Hoy ed.). Univ. California. pp. 1–22.Van de Vrie, M. — 1974. Studies on prey-predator interactions betweenPanonychus ulmi andTyphlodromus (A.)potentillae (Acarina: Tetranychidae, Phytoseiidae) on apple in the Netherlands. — Proceedings FAO Conference on Ecology in relation to pest control. Rome, pp. 145–160
Early delay of gratification predicts later inhibitory control and academic performance in children with prenatal alcohol exposure
Fetal alcohol spectrum disorder (FASD) affects 2–5% of the children in the United States. In the preschool age-range, inhibitory deficits frequently manifest as impaired ability to delay gratification, which is associated with deficits in cognitive flexibility in these children. The goal of this longitudinal study was to determine whether the ability to delay gratification in preschool children with FASD is (1) associated with broader manifestations in temperament and behavior; (2) predictive of later inhibitory control, cognitive flexibility and working memory in middle childhood; and (3) predictive of later parent-reported behavioral problems and school functioning in middle childhood. Forty-seven children with FASD, ages 2.5–5 years were administered a delay of gratification task in which they chose between receiving 2 snacks immediately or 10 snacks after waiting for 10 min. Two groups were defined based on a median split of waiting time. Four years later, 29 children completed measures of inhibitory control (Flanker task), cognitive flexibility (Dimensional Change Card Sort Test), and working memory (Stanford–Binet Intelligence Scales), and their parents completed the Child Behavior Checklist as a measure of the child’s behavioral problems and school functioning. Children with longer wait times on the delay of gratification task in preschool showed better inhibitory control on the Flanker task in middle childhood and better parent-reported school functioning in English. These findings indicate that early inhibitory capacity persists into middle childhood in those with FASD, and may be a promising target for early intervention to improve later cognitive outcomes in these children
Executive and Social Functioning Across Development in Children and Adolescents With Prenatal Alcohol Exposure
Background: Prenatal alcohol exposure (PAE) is linked to a variety of neurodevelopmental challenges, including social functioning (SF) and executive functioning (EF) deficits. These deficits present differently across developmental stages from preschool age to adolescence. Methods: The post hoc analyses described here were conducted on data from 83 preschool-age children with PAE (early childhood group; ages 2.5 to 5.0) and 95 adolescents (49 with PAE, 46 controls; ages 8 to 16). Each child completed EF tasks as part of several prior studies. Parents completed social and communication inventories about their child’s abilities. Thirty-three participants from the early childhood group returned for a 4-year follow-up and completed both SF and EF measures. Results: Both the early childhood and adolescent groups with PAE showed deficits in SF and EF. There was a relationship between SF and EF within the adolescent PAE group that was not present in the adolescent control group or the early childhood PAE group. However, at the 4-year follow-up (Mage = 8.45), participants originally in the early childhood PAE group also demonstrated this relationship. Conclusions: These findings support previous research on EF/SF deficits in adolescents with PAE while also addressing a gap in the literature concerning early childhood research on this topic. Additionally, these findings suggest that the relationship between EF and SF deficits may strengthen throughout development. This line of research highlights potential sensitive periods for SF and EF training in children with PAE and suggests that fetal alcohol spectrum disorders programs consider targeting EF training as a component of social skill interventions
Prey preference and feeding capacity of the larvae ofAblattaria arenaria [Coleoptera: Silphidae], a snail predator
The effect of prey density on the functional and numerical reponses of three species of predatory mites
Executive and Social Functioning Across Development in Children and Adolescents With Prenatal Alcohol Exposure
BACKGROUND: Prenatal alcohol exposure (PAE) is linked to a variety of neurodevelopmental challenges, including social functioning (SF) and executive functioning (EF) deficits. These deficits present differently across developmental stages from preschool age to adolescence. METHOD: The post-hoc analyses described here analyzed data from eighty-three preschool-age children with PAE (early childhood group; ages 2.5–5.0) and ninety-five adolescents (49 with PAE, 46 controls; ages 8–16). Each child completed EF tasks as part of several prior studies. Children’s parents completed social and communication inventories about their child’s abilities. Thirty-three participants from the early childhood group returned for a four-year follow-up and completed both SF and EF measures. RESULTS: Both the early childhood and adolescent groups with PAE showed deficits in SF and EF. There was a relationship between SF and EF within the adolescent PAE group that was not present in the adolescent control group or the early childhood PAE group. However, at the four-year follow-up (M(age)= 8.45), those originally in the early childhood PAE group also demonstrated this relationship. CONCLUSIONS: These findings support previous research on EF/SF deficits in adolescents with PAE while also addressing a gap in the literature concerning early childhood research on this topic. Additionally, these findings suggest that the relationship between EF and SF deficits may strengthen throughout development. This line of research may highlight sensitive periods for SF and EF training in children with PAE and may suggest that FASD programs consider targeting EF training as a component in social skill interventions