Fishes of the Ohio River

Author Institution: Water Resources Laboratory, University of Louisville and Biology Department, Spalding UniversityTo date, 159 species of fishes (14 of them introduced by humans) have been reported from the Ohio River. Three native fishes {Acipenser fulvescens, Alosa alabamae, and Ammocrypta asprella) have apparently been eliminated from the river. The Ohio River fish community was severely affected by the siltation of clean gravel substrates, and the inundation of those substrates by the canalization of the river before 1927. In the past 20-30 years, populations of many species have increased, particularly in the upper third of the river. Some pollution-intolerant species which had disappeared from the upper reaches of the river between 1900 and 1950 have been returning since 1970 (e.g. Polyodon spathula, Hiodon tergisus, and Carpiodes velifer). A few pollution-tolerant species have declined in abundance since 1970 (e.g. bullheads and Ictalurus catus). The most abundant fishes in the lock chamber samples of 1957-87 were Notropis atherinoides, Dorosoma cepedianum, Aplodinotus grunniens, Notropis volucellus, and Ictalurus punctatus. The ongoing recovery of the Ohio River fish community should encourage us to take additional steps to protect the river from catastrophic spills of toxic materials and to reintroduce eliminated native fishes

Jungermannia stygia, Hook, T. et Tayl.

In Mr. Rodway's interesting and useful List of Tasmanian Hepatics (Proc. Royal Sec. Tasm., p. 74, 1916) reference is made to this species, and also to Cesia erosa, Carr. et Pears. The following notes will clear up some misunderstanding with reference to these species

Physical drivers of the cosmic star formation history

Kennis over de opbouw van sterren is cruciaal voor het begrijpen waarom ons universum er vandaag de dag zo uitziet: het zijn de sterren die de nachtelijke hemel verlichten. Dit proefschrift onderzoekt enkele van de drijfveren van deze stervorming over de geschiedenis van het universum.Het verband tussen de snelheid van stervorming en de massa van sterren in sterrenstelsels wordt bestudeerd, tezamen met het verband tussen stervorming en fusies van sterrenstelsels. Hiervoor zijn nieuwe technieken nodig om nauwkeurige schattingen van de stervormingssnelheid te maken en fusies van sterrenstelsels te detecteren. Een belangrijk onderdeel van de schattingen van de stervormingssnelheid, de emissie in het ver-infrarood, heeft te lijden onder een relatief lage resolutie waardoor individuele sterrenstelsels in elkaar op lijken te gaan en niet langer van elkaar te onderscheiden zijn.In dit proefschrift zijn de bestaande technieken voor het onderscheiden van zulke sterrenstelsels verbeterd, waardoor een betere extractie van de helderheid in het ver-infrarood, en daarmee van de stervormingssnelheid, mogelijk is. Dit proefschrift maakt gebruik van de nieuwste technieken om fuserende sterrenstelsels te identificeren in zowel simulaties als echte waarnemingen.Onderzoek naar de relatie tussen de stervormingssnelheid en de massa van sterren in sterrenstelsels heeft uitgewezen dat in het vroege heelal hoge en lage massa sterrenstelsels met dezelfde snelheid sterren vormden. Naarmate het heelal ouder werd, konden de hoge massa sterrenstelsels minder goed nieuwe sterren vormen. Daarnaast bleek dat fusies van sterrenstelsels niet van grote invloed zijn op stervormingssnelheid, maar wel tot uitbarstingen van stervorming kunnen leiden.The build up of stars over the history of the universe is important for understanding why our universe looks the way it does today: it is the stars that create the energy that lights up the night sky. This thesis looks into some of the drivers of this star formation over the history of the universe.The connection between star formation rate and the mass of stars in galaxies is studied along with the connection between star formation and galaxy mergers. To do this, new techniques and tools are required for generating accurate star formation rate estimates and detecting galaxy mergers. A key component of star formation rate estimates, emission in the far-infrared, suffers from relatively low resolution which causes galaxies to blend with one another.In this thesis, existing de-blending tools have been improved, allowing better extraction of far-infrared luminosities and hence better estimates of star formation rates. This thesis also employs the latest deep learning techniques to identify merging galaxies in both simulations and observations of our universe.Studying the relation between the star formation rate and the existing mass of stars in galaxies found that in the early universe, high mass and low mass galaxies formed stars at similar rates. As the universe aged, high mass galaxies become less able to form new stars. For the influence of galaxy mergers on star formation rates, this thesis found that on average, galaxy mergers do not notably influence star formation rates but can trigger starbursts

Patience, Thanksgiving, and Opportunity for Learning

Former Chancellor of Syracuse University, William Tolley, writes about the struggles of the library during the mid-20th century. This article was written amidst the dedication of the Ernest S. Bird Library in 1973. The main virtues needed of an academic administration in the trying times, he believes, is patience, thanksgiving, and the ability to utilize opportunities for learning

Drift of Oligophlebodes sigma and Baetis bicaudatus in a Mountain Stream

The objective of this study was to clarify the relationships between drift rates, population density, production rates, key environmental factors, and movements of adults within two populations of stream insects (a caddisfly--Oligophlebodes sigma and a mayfly--Baetis bicaudatus). Samples of benthic invertebrates (424 total) were collected every 2 8 days at four stations on Temple Fork of the Logan River, Utah, from October, 1967 to September, 1969. Samples of drift invertebrates (181 total) were collected every 14 days at three stations on Temple Fork during the same period. During summer months (June-September) a day and a night drift sample (681 total) were collected every other day. Drift rates of O. sigma larvae were greatest (5,987 gm/year for O. sigma) when density in the benthos (256 mg/0.1 m2) and production (430 mg/0.1 m2 /year) were greatest. Drift rates were not related positively to density in the benthos over an entire year, but drift rates were correlated positively and significantly (r = .78 and .55 for day drift of O. sigma and B. biaaudatus, respectively) with density during the months of June-September for both O. sigma larvae and B. bicaudatus nymphs. Flow, distance below the spring source of Temple Fork, and densities of competing aquatic insects were other factors of significance in the multiple regression analyses of factors affecting drift rates of the two insects. The 17 independent variables in the multiple regression analyses accounted for 65 percent and 55 percent of the variability in day drift rates of o. sigma and B. bicaudatus, respectively. The adults of O. sigma (but not those of B. bicaudatus) undertook a definite upstream migration estimated at 2-3 km. This flight of adults resulted in a concentration of eggs being laid in the upper reaches of the stream. The advantage of the upstream flight may be that it stores reproductive products in areas where they are relatively safe from the effects of anchor-ice in the winter and floods in late winter and early spring

Distribution of Macroinvertebrates in the Green River Below Flaming Gorge Dam, 1963-1965

This study was undertaken to determine the effects of rotenone applied during a fish control operation in September 1962 and the installation of Flaming Gorge Dam in November 1962 upon the distribution of invertebrates in the Green River. Since these two events, the river has changed from a warm, turbid stream to a cold, clear trout stream for about 45 miles below the dam. Totals of 234 bottom samples and 394 drift samples were collected between the dam and Ouray, Utah (166 miles below the dam). The species composition of the fauna above Carr Ranch was much simpler during 1964-65 than the reported pre-impoundment composition. Below Carr Ranch the species composition of the invertebrate fauna has changed little. Bottomfauna densities were highest near the dam (max. 6347/ft. 2) and decreased with increasing distance below the dam. Population densities below Carr Ranch (42.7 miles below the dam) appeared to be similar to reported pre-impoundment densities. Drift rates of Baetis nymphs and Simuliidae larvae were highest near the dam. Illumination, population density. of other organisms, and water temperature had significant effects on drift-net catches of Baetis and Simuliidae. Turbidity and water-level fluctuations had important effects under certain circumstances, while date, dissolved oxygen, and depth of water had little effect on drift - net catches

Quantized Lattice Dynamic Effects on the Spin-Peierls Transition

The density matrix renormalization group method is used to investigate the spin-Peierls transition for Heisenberg spins coupled to quantized phonons. We use a phonon spectrum that interpolates between a gapped, dispersionless (Einstein) limit to a gapless, dispersive (Debye) limit. A variety of theoretical probes are used to determine the quantum phase transition, including energy gap crossing, a finite size scaling analysis, bond order auto-correlation functions, and bipartite quantum entanglement. All these probes indicate that in the antiadiabatic phonon limit a quantum phase transition of the Berezinskii-Kosterlitz-Thouless type is observed at a non-zero spin-phonon coupling, $g_{\text c}$. An extrapolation from the Einstein limit to the Debye limit is accompanied by an increase in $g_{\text c}$ for a fixed optical ($q=\pi$) phonon gap. We therefore conclude that the dimerized ground state is more unstable with respect to Debye phonons, with the introduction of phonon dispersion renormalizing the effective spin-lattice coupling for the Peierls-active mode. We also show that the staggered spin-spin and phonon displacement order parameters are unreliable means of determining the transition.Comment: To be published in Phys. Rev.

The aerodynamic flow over a bluff body in ground proximity: CFD prediction of road vehicle aerodynamics using unstructured grids

The prediction of external automobile aerodynamics using Computational Fluid Dynamics (CFD) is still in its infancy. The restrictions on grid size for practical use limit the ability of most organisations to predict the full flow over an automobile. Some insight into the flow over a passenger car can be made by examining the flow over a bluff body in close proximity to the ground. One such body is the Ahmed body composed of a rounded front, straight mid-section and variable slant-rear section. This body exhibits many of the 3D flow structures exhibited by passenger cars. The main feature of the flow around this body is the change in flow structure as the angle of the slant surface at the rear of the body is increased. The flow starts fully attached and ends fully separated. In between these two regimes is a third high drag regime. The flow structure is characterised by strong counter-rotating longitudinal vortices originating from the interaction between the flow from the sides and top of the body, and a small separation from the top/slant edge on the centre-plane of the body. The flow reattaches to the slant surface and the low-pressure fluid within the separation bubble increases the drag considerably. The use of CFD incorporating tine averaged statistical turbulence models to reproduce these flow patterns is assessed in this study. Initial work concentrated on evaluating structured grid methods for this flow type. Some success was achieved with the flow fields for the attached and fully separated cases but the third high drag regime was not predicted. The flow field also exhibited a grid dependent flow structure and drag result. To examine these effects further without high grid overheads an unstructured mesh generator was developed and used to provide meshes with more grid cells clustered around the body and it's wake. Analysis and refinement of the unstructured grids proved successful at removing the grid dependent flow field but still showed no evidence of the third high drag flow regime. Further, the bulk levels of drag in all cases was too high and the fully separated flow regime occurred too late in the slant surface angle sweep, coming at 40° instead of the 30° seen in the wind tunnel results. Further analysis of the flow field using highly refined mixed meshes showed no improvement in the drag or flow field prediction with the high drag flow field still not present. The use of higher order differencing schemes and anisotropic turbulence models reduced the drag levels considerably but not to the levels seen in the wind tunnel results. Comparison of the results from this work with the work of other authors is difficult for two reasons. Firstly, work on the specific body used in this thesis is sparse and, secondly, much of the work done by other authors was in conjunction with automotive manufacturers and details of the specific numerical methods employed are not available. The most important parallel conclusion from the work presented here and that of other authors is the inability of the CFD prediction to capture the change in flow mode as the angle of slant surface is increased. This failure can, in all probability, be attributed to the use of a steady-state CFD solution algorithm to capture the flow field around the body. A small possibility perhaps still exists that further grid refinement, very localised around the body, would help, but the detailed and careful predictions presented in this study make this highly unlikely. The most important piece of further work that could follow this work would therefore be the application of a time-accurate (unsteady) CFD solution algorithm to the bluff body in ground proximity problem. Whether these predictions should be of an unsteady RANS nature, or full LES predictions would be best answered by applying these methods to the present flow problem which is fundamental to the study of automobile aerodynamics

A two-sling mechanism of hyolaryngeal elevation in the pharyngeal phase of swallowing

Thesis (Ph.D.)--Boston UniversityThe pharyngeal phase of swallowing is a complex function that transfers a bolus from the oral cavity through the hypopharynx into the esophagus. A critical event in this process is the elevation of the hyolaryngeal complex, which opens the upper esophageal sphincter and relocates the airway away from an oncoming bolus. The suprahyoid group of muscles (mylohyoid, geniohyoid, digastric, and stylohyoid) and thyrohyoid are thought to underlie this function. The role of a deeper posterior sling of muscles that is comprised of stylopharyngeus, salpingopharyngeus and palatopharyngeus has not been determined. This project aims to investigate a hypothesized two-sling mechanism for hyolaryngeal elevation in the pharyngeal phase of swallowing. The thesis begins with background information of the functional anatomy thought to underlie hyolaryngeal elevation followed by an outline of studies that validate the structure, function, and clinical relevance of the two-sling mechanism. A cadaver model is first used to calculate potential force vectors of the muscular slings. The function of the two-sling apparatus is then investigated in vivo by using muscle functional MRI to evaluate muscles active in swallowing and dynamic MRI to perform kinematic analysis on key anatomical landmarks that represent attachment sites of the two-sling mechanism. Finally, the clinical significance of the two-sling mechanism is demonstrated by comparing spatial and temporal measurements collected from fluoroscopic imaging studies of patients with normal swallowing ability and swallowing difficulty

Vignette Portrait of A. Lincoln

Photo on a cabinet-size mount, vignette portrait of A. Lincoln taken by T.P. Pearson in 1858. This is a reversed image of original ambrotype. Imprint; Rider...Chicago. Ref: O-8.https://scholarsjunction.msstate.edu/fvw-photographs/1005/thumbnail.jp