Construction of a Bridge Floor Using High Range Water Reducer, Construction Report, HR-192, 1978

The use of a high range water reducer in bridge floors was initiated by an Iowa Highway Research Board project (HR-192) in 1977 for two basic reasons. One was to determine the feasibility of using a high range water reducer (HRWR) in bridge floor concrete using conventional concrete proportioning, transporting and finishing equipment. The second was to determine the performance and protective qualities against chloride intrusion of a dense concrete bridge floor by de-icing agents used on Iowa's highways during winter months. This project was basically intended to overcome some problems that developed in the original research project. The problems alluded to are the time limits from batching to finishing; use of a different type of finishing machine; need for supplemental vibration on the surface of the concrete during the screeding operation and difficulty of texturing. The use of a double oscillating screed finishing machine worked well and supplemental vibration on one of the screeds was not needed. The limit of 45 minutes from batching the concrete to placement on the deck was verified. This is a maximum when the HRWR is introduced at the batch plant. The problem of texturing was not solved completely but is similar to our problems on the dense "Iowa System" overlay used on bridge deck repair projects. This project reinforced some earlier doubts about using truck transit mixers for mixing and transporting concrete containing HRWR when introduced at the batch plant.

Field Performance and Evaluation of Slurry Seals, HR-195, 1980

As part of the overall research program of evaluating asphalt emulsion slurry seal as a pavement maintenance material, 31 duplicate 500-ft test sections were constructed on U.S. 6 between Adel and Waukee in Dallas County during September and October of 1978. These test sections included combinations of eight aggregates, two gradings, three asphalt emulsions, two mineral fillers, and a range of emulsion contents determined by laboratory mix designs. The emulsion contents of the test sections varied from 10.3% for Section 7A (Ferguson coarse) to 32.9% for Section 31A (lightweight aggregate). The post-construction performance evaluation of the test sections, consisting primarily of the friction tests and surface appearance observations, was conducted at different time intervals up to 24 months after construction. At the 24-month final evaluation, most of the test sections had carried a total of 1.4 million vehicles.

Space Competition and Time Delays in Human Range Expansions. Application to the Neolithic Transition

Space competition effects are well-known in many microbiological and ecological systems. Here we analyze such an effectin human populations. The Neolithic transition (change from foraging to farming) was mainly the outcome of a demographic process that spread gradually throughout Europe from the Near East. In Northern Europe, archaeological data show a slowdown on the Neolithic rate of spread that can be related to a high indigenous (Mesolithic) population density hindering the advance as a result of the space competition between the two populations. We measure this slowdown from a database of 902 Early Neolithic sites and develop a time-delayed reaction-diffusion model with space competition between Neolithic and Mesolithic populations, to predict the observed speeds. The comparison of the predicted speed with the observations and with a previous non-delayed model show that both effects, the time delay effect due to the generation lag and the space competition between populations, are crucial in order to understand the observations

Residence time, expansion toward the equator in the invaded range and native range size matter to climatic niche shifts in non-native species

Aim Identifying climatic niche shifts and their drivers is important to accurately predict the risk of biological invasions. The niches of non-native plants and birds have recently been assessed in large-scale multi-species studies, but such large-scale tests are lacking for non-native reptiles and amphibians (herpetofauna). Furthermore, little is known about the factors contributing to niche shifts when they occur. Based on the occurrence of 71 reptile and amphibian species, we compared native and non-native realized niches in 101 invaded ranges at a worldwide scale and identified the factors that affect niche shifts. Location The world except the Antarctic. Methods We assessed climatic niche dynamics in a gridded environmental space allowing the quantification of niche overlap and expansion into climatic conditions not colonized by the species in their native range. We analyzed the factors affecting niche shifts using a model averaging approach based on generalized linear mixed-effects models. Results Approximately 57% of the invaded ranges (51% for amphibians and 61% for reptiles) showed niche shifts (≥10% expansion in the realized climatic niche). Island endemics, species introduced to Oceania and invaded ranges outside the native biogeographic realm showed a higher proportion of niche shifts. Niche shifts were more likely for species that had smaller native range sizes, were introduced earlier into a new range or invaded areas located at lower latitudes than the native range. Main conclusions The proportion of niche shifts for non-native herpetofauna was higher than those for Holarctic non-native plants and European non-native birds. The 'climate matching hypothesis' should be used with caution for species shifting their niche because it could underestimate the risk of their establishment.

Variation in the proportion of flower visitors of Arum maculatum along its distributional range in relation with community‐based climatic niche analyses

Here, we investigate the geographical constancy in the specificity level of the specialized lure-and-trap pollination antagonism involving the widespread European Arum maculatum and its associated Psychodid pollinators. Until now, studies concurred in demonstrating that one single insect species, Psychoda phalaenoides, efficiently cross-pollinated plants; researches were, however, performed locally in western Europe. In this study we characterize for the first time the flower visitors' composition at the scale of the distribution range of A. maculatum by intensively collecting plants and insects throughout the European continent. We further correlate local climatic characteristics with the community composition of visiting arthropods.Our results show that flowers are generally visited by P. phalaenoides females, but not over the whole distribution range of the plant. In some regions this fly species is less frequent or even absent and another species, Psycha grisescens, becomes the prevailing visitor. This variability is geographically structured and can be explained by climatic factors: the proportion of P. grisescens increases with higher annual precipitations and lower precipitations in the warmest trimester, two characteristics typical of the Mediterranean zone. Climate thus seems driving the specificity of this interaction, by potentially affecting the phenology of one or both interacting species, or even of volatile and heat production in the plant. This result therefore challenges the specificity of other presumably one-to-one interactions covering wide distribution ranges, and provides an example of the direct effect that the abiotic environment can have on the fate of plant-insect interactions.

2014 Registered Flex Fuel Vehicles

Iowa Code section 452A.33(3) requires a report regarding flexible fuel vehicles registered in Iowa. The report includes the number of flexible fuel vehicles according to year of manufacture; the number of passenger vehicles according to year of manufacture; and the number of light pickup trucks according to the year of manufacture.

Anàlisi hidrodinàmic de vehicles submarins mitjançant eines de simulació CFD

El grup VICOROB de la UdG té una àmplia experiència en l’àmbit dels vehicles irobots submarins, amb diferents prototips degudament validats experimentalment.L’interès d’aquest grup de recerca és anar més enllà i conèixer exactament elcomportament del vehicle dins de l’aigua.El grup VICOROB disposa d’un vehicle subaquàtic, l’anomenat GIRONA 500 que haestat dissenyat com una plataformad'investigació amb capacitat per tornara configurar-se per a moltes aplicacionsdiferents, que van des dels clàssicssonar i servei d’imatges de vídeo fins atasques d'intervenció autònomesdifícilsL’objectiu és d’aquest projecte és obtenir a partir de la geometria real del vehicleGIRONA 500 els coeficients hidrodinàmics del submarí complet i de solamentl’estructura per així conèixer l’efecte hidrodinàmic del nombre de propulsors acoblats alrespectiu vehicle aquàtic

Lee County, Township 67 North Range 7 West

Des Moines River Plat Maps.

Van Buren County, Township 67 North Range 8 West

Des Moines River Plat Maps.

Van Buren County, Township 67 North Range 9 West

Des Moines River Plat Maps.

Lee County, Township 68 North Range 7 West

Des Moines River Plat Maps.

Van Buren County, Township 68 North Range 8 West

Des Moines River Plat Maps.

Van Buren County, Township 68 North Range 9 West

Des Moines River Plat Maps.

Van Buren County, Township 68 North Range 10 West

Des Moines River Plat Maps.