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Additional file 1. Semi-structured interview guide.

An aging swing bridge in New Jersey has been replaced with a twin concrete box girder crossing that sets a U.S. record for span length using matchcast concrete segments. By using a carefully staged construction sequence, the first of the parallel structures was built adjacent to the existing bridge in just 15 months. Superstructure erection of the remaining crossing is on track to be completed in just 9 months.

Practical instructors are used at Southern Illinois University School of Medicine to: serve as subjects on whom students practice prior to meeting with physicians; instruct students in the techniques of performing physical examinations; and evaluate students' performance both from objective predetermined criteria and from their subjective points of view. (LBH)

Describes a preschool class for handicapped children in which speech development is fostered through use of manual signing in combination with spoken language. (SB)

The accuracy of soil and plant analytical results are occasionally called into question by laboratory clientele. Although laboratories generally conduct internal quality assurance procedures, there are few external performance testing programs for the industry. In the spring of 1994, a proficiency testing program was initiated for soil and plant samples for agricultural laboratories in the Western United States to provide an external quality control for the laboratory industry. The program involves the quarterly exchange of soil and plant samples on which soil salinity, soil fertility, and plant nutrition analyses are conducted. For the 1994 program, 103 laboratories from 23 states and Canadian provinces participated. Overall, soil salinity and pH analyses were highly reproducible across soils and laboratories through the year. Variability in soil nitrate results were lower than noted in past interlaboratory exchanges independent of soil sample. Results for extractable soil bicarbonate phosphorus...

DRiWATER*, a poly cellulose gel containing 97.98% water, is a moisturizing substrate made from cellulose gum, alum and aerated water. The substrate which is decomposed by micro‐organisms slowly releasing water, is intended for use on house plants, other container grown plants and newly planted trees and shrubs as a substitute for frequent or costly watering. The manufacturer's label claims that the substrate will water plants for 30 days, will save time and water, and eliminate over watering. A test to determine the efficacy of the poly cellulose and to verify label claims was conducted. Four replicates of two rates of water, three rates of the substrate and an unirrigated check were applied to azaleas, Rhododendron indicum, in one gallon pots. Poly cellulose treated plants were maintained through a four week period. The gel disappeared over a 3 to 4 week period. Irrigated plants grew well. Efficacy claims for DRiWATER* were substantiated.

How we define a problem often determines what we are willing to consider as a solution. When we define the impending extinction of a sea turtle species solely in terms of there being too few turtles, we are tempted to think of solutions solely in terms of increasing the numbers of turtles. Hence, some of our attempts to conserve sea turtles involve “halfway technology,” which does not address the causes of or provide amelioration for the actual threats turtles face. Programs such as headstarting, captive breeding, and hatcheries may serve only to release more turtle into a degraded environment in which their parents have already demonstrated that they cannot flourish. Furthermore, captive programs may keep turtles from serving important ecological functions in the natural environment, or place them at some disadvantage relative to their natural counterparts once released. Such programs can be contrasted with more appropriate technologies that directly address and correct particular problems encountered by sea turtles without removing them from their natural habitat. For example, installing turtle excluder devices in shrimp trawl nets will reduce mortality of adults and larger juvenile sea turtles, and using low pressure sodium lighting on beaches may prevent hatchlings and nesting females from becoming disoriented. In the final analysis, we need clean and productive marine and coastal environments. Without a commitment to such long term goals, efforts to protect sea turtles will be futile. Resumen: La forma en que definimos un problema, usualmente determinara que es lo que estamos dispuestos a aceptar como solucion. Cuando definimos la inminente extincion de la tortuga de mar, solamente en terminos de que quedan muyrpocas tortugas, nos vemos tentados a pensar en soluciones solamente en terminos de incrementar el numero de las mismas. Por consiguiente, alguna de las cosas que hacemos en nuestros intentos para conservar tortugas de mar involucra una “tecnologia a medias, ” que no considera las causas ni brinda medidas que tiendan a disminuir los peligros reales que las tortugas enfrentan. Programas como “headstarting” (cria de tortugas desde la etapa de huevo hasta unos 9 meses de edad, antes de liberarlas al medio ambiente), cria en cautiverio y viveros, serviran solamente para liberar mas tortugas a un medio ambiente deteriorado en el cual sus padres ya han demostrado que no pueden prosperar: Mas aun, programas de animales en cautiverio, podrian impedir que las tortugas cumplan importantes funciones ecologicas en su medio ambiente natural, o las colocarian en desventaja con respecto a sus contrapartes naturales una vez liberadas. Dichos programas pueden ser comparados con tecnologias mas apropiadas que dirijan y corrijan directamente problemas particulares que las tortugas de mar encuentran, sin sacarlas de su medio ambiente natural. Por ejemplo, la instalacion de dispositivos que excluyan las tortugas de las redes de pezca de camarones reducira la mortalidad de los adultos y de las tortugas juveniles de mayor tamano; el use de iluminacion de sodio de baja presion en playas, podria prevenir que las crias y las hembras se desorientasen. En concreto, lo que se necesita son ambientes costeros y marinos limpios y productivos. Sin un compromiso a largo plazo sobre dichos objetivos, los esfuerzos por protejer las tortugas de mar sera inutiles.

This paper presents a life table for the common mud turtle, Kinosternon subrubrum, in a fluctuating aquatic habitat on the Upper Coastal Plain of South Carolina, USA, using data gathered in a 20—yr mark—recapture study. Data on survivorship and fecundity (clutch size, per capita clutch frequency) were assessed and compared to previously published life table statistics for the slider turtle, Trachemys scripta, in the same body of water and for the yellow mud turtle, K. flavescens, in Nebraska. The annual survival rate for adult female Kinosternon (87.6%) is significantly higher than that of adult female Trachemys (77.4%). Similarly, male Kinosternon exhibit an annual survival rate (89.0%) significantly higher than that of male Trachemys (83.4%). The mean annual proportion of female Kinosternon that are reproductively active (50.7%) also is significantly higher than that of Trachemys (37.2%). In addition, survival rate from the time eggs are laid by Kinosternon until the hatchlings enter the aquatic environment (26.1%) is significantly higher than that for Trachemys (10.5%). Comparisons of our findings with those for K. flavescens indicate that these geographically separate populations of congeneric species also differ substantially in age at maturity, mean generation time, and the mean proportion of females that are reproductively active in any given year. Differences were also apparent in mean clutch frequencies and adult survival rates. The differences in life history traits between the two geographically separated populations of congeners seem to be as great as those between the two syntopic populations representing different families (Kinosternidae: K. subruburm and Emydidae: Trachemys scripta). The comparison of life tables for two species from different families having different ecological and evolutionary histories, but living in the same habitat, and of congeneric species in different habitats, is instructive regarding the biological flexibility of species under natural conditions. However, the study suggests that environmental variability has a greater effect on life table statistics than do phylogenetic relationships.