Vacuum ultraviolet holography

The authors report the first demonstration of holographic techniques in the vacuum ultraviolet spectral region. Holograms were produced with coherent 1182 A radiation. The holograms were recorded in polymethyl methacrylate and read out with an electron microscope. A holographic grating with a fringe spacing of 836 A was produced and far-field Fraunhofer holograms of sub-micron particles were recorded

Handbook for estimating toxic fuel hazards

Computer program predicts, from readily available meteorological data, concentration and dosage fields downwind from ground-level and elevated sources of toxic fuel emissions. Mathematical model is applicable to hot plume rise from industrial stacks and should also be of interest to air pollution meteorologists

Receptividad de los adolescentes al pensamiento sobrenatural de los niños: ¿una preparación para la paternidad?

Background: Young children often use magical explanations to account for ordinary phenomena (e.g., “The sun’s not out today because it is mad”). We labeled these explanations supernatural thinking. Previous research reports that supernatural thinking attributed to preschool-age children evokes both positive affect and perceptions of helplessness from both adults and older (14-17 years old) but not younger (10-13 years old) adolescents. In this study, we asked if cues of cognitive immaturity are more infl uential in affecting adolescents’ judgments of children than physical cues (faces). Method: 245 adolescents aged between 10 and 17 rated pairs of children who physically and/or cognitively resembled either a 4- to 7-year-old or an 8- to 10-year-old child in three between-subject conditions (Consistent, Inconsistent, Faces-Only) for 14 traits classifi ed into four trait dimensions (Positive Affect, Negative Affect, Intelligence, Helplessness). Results: For both younger and older adolescents, cognitive cues had a greater infl uence on judgments than facial cues. However, only the older adolescents demonstrated a positive bias for children expressing immature supernatural thinking. Conclusions: Adopting an evolutionary developmental perspective, we interpreted this outcome in late (but not early) adolescence as preparation for potential parenthood.Antecedentes: los niños pequeños emplean a menudo explicaciones mágicas para referirse a fenómenos cotidianos (por ejemplo, “El sol no sale hoy porque está enfadado”). Nosotros etiquetamos estas explicaciones como pensamiento sobrenatural. Investigaciones anteriores muestran que el pensamiento sobrenatural atribuido a niños en edad preescolar evoca afecto positivo y percepción de desamparo en adultos y adolescentes mayores (14-17 años) pero no en adolescentes jóvenes (10-13 años). En este estudio nos preguntamos si las señales de inmadurez cognitiva son más infl uyentes en los juicios de los adolescentes que las señales físicas (caras). Método: 245 adolescentes de 10 a 17 años evaluaron pares de niños que emulaban físicamente y/o cognitivamente a niños de 4 a 7 años o niños de 8 a 10 años en tres condiciones (Consistente, Inconsistente, Solo-Caras) respecto a 14 rasgos clasifi cados en cuatro dimensiones (Afecto Positivo, Afecto Negativo, Inteligencia, Desamparo). Resultados: tanto en adolescentes jóvenes como en mayores, las señales cognitivas tuvieron mayor infl uencia que las señales faciales. Sin embargo, solo los adolescentes mayores mostraron un sesgo positivo hacia niños que expresaban pensamientos sobrenaturales. Conclusión: adoptando una perspectiva evolucionista del desarrollo, interpretamos este resultado en la adolescencia tardía (no temprana) como preparación para la paternidad

Geology and Ground-Water Resources of the Lower South Platte River Valley Between Hardin, Colorado, and Paxton, Nebraska

The study of the geology and ground-water resources of the lower South Platte River valley was made by the Ground Water Branch of the U. S. Geological Survey at the request of the U. S. Bureau of Reclamation and with the endorsement of the Colorado Water Conservation Board. The area includes parts of Colorado and Nebraska, covers about 3,200 square miles, and ranges in altitude from about 3,000 to 5,000 feet above sea level. The average annual precipitation in the area is about 16 inches and is sufficient to support grasses and some grains. Irrigation utilizing water diverted from the river and pumped from wells is extensively developed in the valleys of the South Platte River and its tributaries. The principal agricultural products are Corn, sugar beets, alfalfa, beans, wheat, barley, and livestock. The rocks exposed in the area are sedimentary and range in age from Late Cretaceous to Recent. The Pierre shale underlies the entire area. The Fox Hills sandstone and the Laramie formation underlie the western part and the Chadron, Brule, and Ogallala formations underlie the eastern part. Pleistocene arid Recent alluvium underlies the valleys of the South Platte River and its tributaries. The Pierre shale ranges in thickness from about 2,500 feet near Paxton, Nebr., to about 6,500 feet near Hardin, Colo., and yields water in small quantities to wells in the vicinity of Sterling, Colo. Within the area, both the Fox Hills sandstone and the Laramie formation range in thickness from a featheredge to nearly 200 feet and yield small quantities of water to stock and domestic wells. Although a test hole near Proctor, Colo., was drilled 102 feet into the Chadron formation, the total thickness of the formation was not ascertained; no wells within the area covered by this investigation are known to derive water from the formation. The Brule formation ranges in thickness from a featheredge to more than 500 feet and yields water to wells from fractured or porous zones. The Ogallala formation ranges in thickness from a featheredge near Sedgwick, Colo., to about 350 feet near Paxton, Nebr., and yields large quantities of water to wells. The alluvium ranges in thickness from a featheredge at the edges of valleys to about 300 feet in some places in the valleys. The alluvium occurs in two physiographic forms Pleistocene and Recent terrace deposits and Recent floodplain deposits and yields abundant water to irrigation, public-supply, and other wells. Dune-sand deposits cover part of the area, range in thickness from a featheredge to about 100 feet, and yield water in small quantities to stock and domestic wells. Loess deposits cover much of the area and range in thickness from a featheredge to about 50 feet. Generally the loess is above the water table and is not known to yield water to wells

Analyzing false memories in children with associative lists specific for their age

Two experiments attempted to resolve previous contradictory findings concerning developmental trends in false memories within the Deese-Roediger-McDermott (DRM) paradigm by using an improved methodology-constructing age-appropriate associative lists. The research also extended the DRM paradigm to preschoolers. Experiment 1 (N = 320) included children in three age groups (preschoolers of 3-4 years, second-graders of 7-8 years, and preadolescents of 11-12 years) and adults, and Experiment 2 (N = 64) examined preschoolers and preadolescents. Age-appropriate lists increased false recall. Although preschoolers had fewer false memories than the other age groups, they showed considerable levels of false recall when tested with age-appropriate materials. Results were discussed in terms of fuzzy-trace, source-monitoring, and activation frameworks

An Exact Algorithm for TSP in Degree-3 Graphs via Circuit Procedure and Amortization on Connectivity Structure

The paper presents an O^*(1.2312^n)-time and polynomial-space algorithm for the traveling salesman problem in an n-vertex graph with maximum degree 3. This improves the previous time bounds of O^*(1.251^n) by Iwama and Nakashima and O^*(1.260^n) by Eppstein. Our algorithm is a simple branch-and-search algorithm. The only branch rule is designed on a cut-circuit structure of a graph induced by unprocessed edges. To improve a time bound by a simple analysis on measure and conquer, we introduce an amortization scheme over the cut-circuit structure by defining the measure of an instance to be the sum of not only weights of vertices but also weights of connected components of the induced graph.Comment: 24 pages and 4 figure