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ABSTRACT:Stream mitigation is widely used to offset and restore anthropogenic stream degradations, yet ecosystem health is not always improved. Specific mitigation type may play a role in the potential for biotic improvement, with differing common mitigation practices including restoration and habitat enhancement. By looking at small factors in stream communities, such as macroinvertebrates, a larger connection can be made to the overall biotic integrity and quality of the aquatic habitat. This study used a Before-After-Control-Impact design to evaluate changes to biotic integrity of four streams in western North Carolina that underwent either complete restoration or habitat enhancement as compensatory mitigation under provisions of the United States Clean Water Act. We developed a Habitat Quality Improvement Index (HQII) to compare macroinvertebrate family-based metrics of habitat quality between 2011 (pre-mitigation) and 2021 (post-mitigation) and used a multivariate analysis to examine changes in macroinvertebrate family composition at each site. Analysis of HQII values using a Monte Carlo resampling procedure showed significant improvement at restored sites, whereas habitat quality declined significantly at sites that underwent habitat enhancement only. Our results indicate that restoration practices can have positive impacts on stream health, especially where habitat degradation is localized, and macroinvertebrate populations at high-quality upstream sections can provide a source for recolonization once habitat conditions improve.

AbstractGlyptodontinae stand out among the lineages of Glyptodontidae in having the greatest latitudinal distribution, including participation in the Great American Biotic Interchange, with significant speciation in new migration areas. The oldest records of Glyptodontinae occur in northern South America with Boreostemmafrom the middle Miocene–Pliocene. A later radiation incorporated the austral representatives ‘Glyptodontidium tuberifer’, ‘Paraglyptodon’ spp., Glyptodon munizi, Glyptodon reticulatusand Glyptodon jatunkhirkhiin the late Miocene–Late Pleistocene of southern South America, and the septentrional representatives Glyptotherium texanumand Glyptotherium cylindricumin the Pliocene–Late Pleistocene of North America, Central America and northeastern South America. Although knowledge of North and South American forms has increased in recent years, records from Central America are still scarce and fragmentary. Here we describe the most complete Central American glyptodontine fossils documented to date, which were recovered from the latest Pleistocene of Guatemala. The remains comprise: (1) an incomplete skull, the right and left hemimandibles, a fragmentary pelvis, cervical and caudal vertebrae, and articulated and isolated osteoderms; (2) a fragmentary pelvis, left hind limb (incomplete autopodium) and seven caudal vertebrae; (3) most of a dorsal carapace; (4) six incomplete caudal armature rings; and (5) a left hemimandible with complete dental series. Comparative assessment indicates that these remains are referrable to G. cylindricum. The presence of this species in northern Central America and northern South America during the latest Pleistocene spans more than 2200 km, suggesting a continuous distribution across this region, at least during the Last Glacial Maximum and the early Younger Dryas.Francisco Cuadrelli [f.cuadrelli@gmail.com]*, Juan Escamilla [juanitoesca@gmail.com] and Alfredo Zurita [aezurita74@yahoo.com], Laboratorio de Evolución de Vertebrados y Ambientes Cenozoicos–Centro de Ecología Aplicada del Litoral (CECOAL–CONICET) y Universidad Nacional del Nordeste, Corrientes, Argentina, 3400; David D. Gillette [daviddgillette@gmail.com], 24 W. Travertine Trail, Flagstaff, AZ 86005, USA; Lorena S. Dávila [sylodavila@gmail.com], Colección de Fósiles, Museo Historia Natural, Universidad de San Carlos de Guatemala, Calle Mariscal Cruz 1–56, Zona 10, Ciudad de Guatemala, Guatemala, 01010.

SUMMARY * Examines how motion can be used to create effective interactive information systems * Demonstrates how a number of cinema techniques influence new media production and can be applied [...]

DEFINING THE ROLE OF INTERACTIVITY Online information can be presented in a variety of formats, from the informal exchange that takes place via e-mail to the complex instructional tasks documented [...]

SUMMARY * Asserts that embedding computers in the world will alter information designs for two-dimensional on-screen spaces * Argues for incorporation of commercial design, cognitive psychology, and architectural and civil [...]

More than 220 million years ago, the Earth was in transition. Pangaea, the World Continent, was the predominant landmass, the Atlantic Ocean did not exist, and dinosaurs roamed the land. [...]

Many studies have assessed the effects of large dams on fishes and macroinvertebrates, but few have examined the effects of lowhead dams. We sampled fishes, macroinvertebrates, habitat, and physicochemistry monthly from November 2000 to October 2001 at eight gravel bar sites centered around two lowhead dams on the Neosho River, Kansas. Sites included a reference site and a treatment site both upstream and downstream from each dam. Multivariate analysis of variance indicated that habitat, but not physicochemistry, varied immediately upstream and downstream from the dams, with resultant effects on macroinvertebrate and fish assemblages. Compared with reference sites, upstream treatment sites were deeper and had lower velocities and downstream treatment sites were shallower and had higher velocities; both upstream and downstream treatment sites had greater substrate compaction than reference sites. Macroinvertebrate richness did not differ among site types, but abundance was lowest at downstream treatment sites and evenness was lowest at upstream treatment sites. Fish species richness did not differ among site types, but abundance was highest at downstream reference sites and evenness was highest at upstream sites. The abundance of some benthic fishes was influenced by the dams, including that of the Neosho madtom Noturus placidus, which was lowest immediately upstream and downstream from dams, and those of the suckermouth minnow Phenacobius mirabilis, orangethroat darter Etheostoma spectabile, and slenderhead darter Percina phoxocephala, which were highest in downstream treatment sites. Although limited to one system during a 1-year period, this study suggests that the effects of lowhead dams on fishes, macroinvertebrates, and habitat are similar to those reported for larger dams, providing important considerations for riverine ecosystem conservation efforts.

Mainframe and networked computers provide faculty and students the opportunity to carry on classroom discussions, or conversations that might never take place, even after the bell rings. Internet and World Wide Web facilities provide additional sources of ideas and information and limitless opportunities for students to engage the world of economics outside the classroom. With examples of real world experiences using e-mail, electronic conferences, and the World Wide Web, this paper provides readers with an exposure to some of the uses as well as the costs and benefits associated with incorporating these types of electronic components into economics courses. Instructors who value the processes of discussion, dialogue, and public discourse and who are interested in incorporating these forms of electronic resources into their courses, whether serving small or large numbers of students, will find useful ideas for enhancing economics courses.

A partial cranium with upper dentition and an isolated rib of the extinct short-faced bear, Arctodus simus, were associated with a nearly complete skeleton of the Columbian mammoth, Mammuthus columbi, at a high elevation site in Huntington Canyon in the Wasatch Mountains of central Utah. This large A. simus was a decidedly short-faced individual. Radiometric dates for the mammoth cluster around the interval ±11,220-11,400 BP; dates for spruce wood in stratigraphic position above and below the mammoth skeleton cluster around ±9,400 BP. Assuming direct association with the mammoth, the occurrence of Arctodus simus at ≤ 11,400 BP is a new terminal date for the species. The mammoth and bear may have been associated with humans in the Huntington Canyon vicinity. The late Quaternary high elevation fauna of Utah includes 30 genera from sites above 1,950 meters above mean sea level. Late Quaternary high elevation faunas of the central and southern Rocky Mountains included the short-faced bear, and may have persisted as relict populations until 10,000 BP or later.

Seismosaurus halli, gen. et sp. nov. (Sauropoda, Diplodocidae) is a new large sauropod from the Brushy Basin Member of the Morrison Formation (Upper Jurassic/Lower Cretaceous) of central New Mexico. The holotype is a partially articulated skeleton consisting to date of approximately 20 caudal vertebrae, five sacral vertebrae, eight dorsal vertebrae, partial pelvis, five chevrons, and ribs. Distinguishing features include the structure of the caudal vertebrae, pelvis, and chevrons. The extraordinary dimensions of these bones indicate an axial length of 39-52 meters.

Many studies generate the impression that agriculture in the United States behaves procyclically with respect to monetary policy. In this paper, a macroeconomic model is presented in which agriculture can be either pro‐, counter‐, or acyclical. It includes two internationally traded goods, a non‐internationally traded good, nominal wage rigidities, and a money market. These features allow exploration of the hypothesis that a positive aggregate demand disturbance that causes an expansion in real U.S. economic activity might simultaneously cause a decline in the real value of agricultural output.

Limited classroom instruction time is a binding constraint for professors teaching economics. Time requirements necessary to learn economics also impose similar constraints on students. The topic of this paper is the presentation of an environment that can both increase the economic content delivered during classroom instruction and increase the potential for students' learning economics outside the classroom. The methodology is two fold: HyperLecturing, a classroom presentation style where computer resources serve as instructional aides; and Linkages, an emphasis on interdisciplinary connections to other course material in a student's repertoire.The specific setting in this paper is Intermediate Macroeconomic Theory, but the methodology generalizes to any course in economics.

Hope and a limited understanding of ocular metabolism prompted the empiric use of numerous drugs1 in an attempt to check the development and cause the absorption of the opacities of incipient senile cataracts.The failure of these remedies, together with an increasing knowledge of the physiology of the endocrine glands, stimulated the use of glandular preparations in ophthalmic research and practice.Van Zandt2 described the visual disturbances incident to cataracts in his cases and attributed the temporary improvement in visual acuity to his endocrine therapy. He concluded that dysfunction of the thyroid was the activating agent, while dysfunctions of the gonads and of the pituitary were adjuvants, in the production of the senile opacities of the lens.Kerr and his associates3 reported some success following the oral use of thyroid substance for senile cataract.Kirby4 administered parathyroid extract to a group of selected patients with cataract

Glossary and Manual of Tetrapod Footprint Palaeoichnology, edited by Giuseppe Leonardi, 1987. Departamento Nacional da Pro-ducao Mineral. Setor de Autarquias Norte, Quadra 1, Bloco B. 70040 Brasilia, OF. Brasil. Telex 0611116. xi + 117 pages, Plates I-XX. [Price + information on ordering]

Several letters to the editor are presented in response to the article "OPM: Pay Reform by 2011" in the June 29, 2009 issue.

Late Quaternary fossils from southeastern United States previously assigned to Felis yagouaroundi and new records of small felines from three additional localities represent an extinct new species. The new species is characterized by an exceptionally tall inferior canine, stout mandibular symphysis and diastema, and relatively slender cheek teeth. Dental characters most closely resemble those of Central and North American F. wiedii and F. tigrina, whereas mandibular characters most closely resemble those of F. yagouaroundi. Evolutionary relationships between the three extant species and the extinct new species are unclear.

Many flexural shell transducers are constructed of independently driven segments. It has been observed that this construction often leads to undesirable nulls and peaks in the acoustic response arising from acoustic interaction of the segments. Methods for minimizing the effects of these interactions will be presented along with supporting modeling results. [Work supported by SPAWAR, Code 182.]