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Estimation Of Body Density In Adolescent Athletes, W G. Thorland, G O. Johnson, G D. Tharp, T J. Housh, C J. Cisar Jan 1984

Estimation Of Body Density In Adolescent Athletes, W G. Thorland, G O. Johnson, G D. Tharp, T J. Housh, C J. Cisar

Faculty Publications

National samples of 141 male and 133 female highly-trained adolescent athletes were studied to derive anthropometric-based equations predicting body density. Anthropometric measures included skinfold thicknesses at seven sites, circum- ferences at 14 sites, and diameters at nine sites. Criterion measures of body density were determined by underwater weighing with corrections for residual lung vol- ume based on the oxygen dilution method. Variable selection procedures included factor analysis followed by forward-stepping regression and polynomial analysis. For both the male and female samples, two quadratic equations utilizing either the sum of three or seven skinfold measures were derived. Within the male sample, …

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Interactive Image Processing For Electron Microscopy: Matching Hardware With Software, W. O. Saxton Jan 1984

Interactive Image Processing For Electron Microscopy: Matching Hardware With Software, W. O. Saxton

Scanning Electron Microscopy

The image processing techniques used 'a posteriori' to extract information from electron micrographs are surveyed, including particularly image averaging, selective averaging, 3-D reconstruction, and high resolution focal series restoration; recent developments in online image pick up and control have led to fully automatic focussing, stigmating and alignment by a frame store system equipped with a real time correlator board. The diversity of the techniques encountered calls for large integrated program systems with flexible command languages; however, a dilemma exists between providing the user with convenient control of special hardware facilities such as frame stores and array processors, and preventing the …

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A Brave New World: The Influence Of Biotechnology On Society, Its Health, And The Environment Jan 1984

A Brave New World: The Influence Of Biotechnology On Society, Its Health, And The Environment

Journal of the Minnesota Academy of Science

No abstract provided.

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Nest Predators And Breeding Birds: Do Initial Vocalizations Correlate With Predator Type And Future Defense Strategy?, Bradley M. Gottfried, Michaela Haug, Kathryn Andrews Jan 1984

Nest Predators And Breeding Birds: Do Initial Vocalizations Correlate With Predator Type And Future Defense Strategy?, Bradley M. Gottfried, Michaela Haug, Kathryn Andrews

Journal of the Minnesota Academy of Science

The initial vocalizations of breeding catbirds in response to predator models positioned at their nests were analyzed to determine if they were correlated with the type of later defense employed (attack model vs. no attack), intensity of defense, and type of predator model (snake vs. blue jay). Statistical differences were found in the types and numbers of vocalizations used in relation to type of nest predator and form of future defense. The data suggest that the initial catbird vocalizations may indeed encode a variety of information.

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Recoveries Of Great Horned Owls Banded In Central Minnesota, Robert T. Bohm Jan 1984

Recoveries Of Great Horned Owls Banded In Central Minnesota, Robert T. Bohm

Journal of the Minnesota Academy of Science

Although great horned owls (Bubo virginianus) are often considered permanent residents, data from band returns have shown that movements by this species do occur. In banding activities conducted in central Minnesota from 1967 through 1983, 329 great horned owls were banded and 24 (7.3 percent) recoveries were reported. Twelve of the 24 recoveries (50.0 percent) were made 15 kilometers or more from where the individuals were banded. Five of these recoveries ( 41.7 percent) were to the southeast. Of 23 owls recovered dead, eight (34 .8 percent) were reported only as "found dead," seven (30.4 percent) were found near highways …

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Ecological And Evolutionary Considerations Of Large Scale Mosquito Control Programs, Harrison B. Tordoff Jan 1984

Ecological And Evolutionary Considerations Of Large Scale Mosquito Control Programs, Harrison B. Tordoff

Journal of the Minnesota Academy of Science

No abstract provided.

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A Brief Overview Of The Life History, Physiology, And Ecology Of Minnesota Mosquitoes, Roger D. Moon Jan 1984

A Brief Overview Of The Life History, Physiology, And Ecology Of Minnesota Mosquitoes, Roger D. Moon

Journal of the Minnesota Academy of Science

The 51 species of mosquitoes known to occur in Minnesota share many biological attributes. They develop through seven life stages: an egg, four larval instars, a pupa, and an adult. Females lay eggs either on water or in substrates likely to be submerged later. Larvae and pupae occur in still , shallow water. Habitats vary among species and include tree holes, temporary snowmelt pools, rain pools, semi-permanent marshes, ponds, and riverside lagoons. Duration of the stages can be affected by diapause, temperature, and nutrition. Many species overwinter as dormant eggs, while some overwinter as larvae and others as diapausing females. …

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Mosquitoes As Vectors Of Disease In Minnesota, John W. Washburn Jan 1984

Mosquitoes As Vectors Of Disease In Minnesota, John W. Washburn

Journal of the Minnesota Academy of Science

Diseases due to mosquito-borne viruses occur every summer in Minnesota. The incidence of Western encephalitis and LaCrosse encephalitis is usually low, but outbreaks of Western encephalitis have occurred in the past. Evidence of Jamestown Canyon virus activity has been found in Minnesota. This virus may represent a newly-recognized cause of central nervous system disease and encephalitis. The epidemiology of the mosquito-borne encephalitis viruses found in Minnesota and the methods of disease surveillance and control are discussed.

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Potential Effects Of Insecticides On The Survival Of Dabbling Duck Broods, Patrick W. Brown, Malcolm L. Hunter Jr. Jan 1984

Potential Effects Of Insecticides On The Survival Of Dabbling Duck Broods, Patrick W. Brown, Malcolm L. Hunter Jr.

Journal of the Minnesota Academy of Science

The effect of insecticides on the survival of dabbling duck broods was investigated by reviewing studies of natural brood survival and depression of growth rates for ducklings raised on wetlands treated with insecticides. Ducklings raised on an insecticide-treated wetland took 5 days longer to reach the normal 14-day body weight. Normal brood mortality for three species of dabbling ducks was highest in the first two weeks of life and ranged from 25% to 51%. High mortality of young ducklings is probably related to their small size. Thus, mortality rates could be in creased to 35% to 70% because of the …

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Technical Session - Panel Discussion, Questions, And Concluding Remarks Jan 1984

Technical Session - Panel Discussion, Questions, And Concluding Remarks

Journal of the Minnesota Academy of Science

No abstract provided.

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Technical Session Summaries: Issues Relating To Mosquitoes And Their Management Jan 1984

Technical Session Summaries: Issues Relating To Mosquitoes And Their Management

Journal of the Minnesota Academy of Science

No abstract provided.

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Public And Legislative Session Summaries Jan 1984

Public And Legislative Session Summaries

Journal of the Minnesota Academy of Science

No abstract provided.

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Potassium 1,3,3a,8a-Tetrahydro-3a,8a-Dihydroxy-2,8-Dioxoindeno[1,2-D]Imidazole-2-Ethanesulfonate, K+.C12h11n2o7s- / By D. D. Bray And D. D. Clarke Chemistry Department, Fordham University, Bronx, Nyew York 10458, Usa And N. Chatterjie And B. Sinha Institute For Basic Research In Development Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, Usa, Diana Bray, Donald Dudley Clarke Phd, Nithiananda Chatterjie, B. Sinha Jan 1984

Potassium 1,3,3a,8a-Tetrahydro-3a,8a-Dihydroxy-2,8-Dioxoindeno[1,2-D]Imidazole-2-Ethanesulfonate, K+.C12h11n2o7s- / By D. D. Bray And D. D. Clarke Chemistry Department, Fordham University, Bronx, Nyew York 10458, Usa And N. Chatterjie And B. Sinha Institute For Basic Research In Development Disabilities, 1050 Forest Hill Road, Staten Island, New York 10314, Usa, Diana Bray, Donald Dudley Clarke Phd, Nithiananda Chatterjie, B. Sinha

Chemistry Faculty Publications

Mr = 366·40, monoclinic, P2/c, Z = 4, a=6·195 (1), b= 17·701 (4), c= 1.2·864 (3)A, P= 116·25(2)0 , V=l387·8A3, Dm=1·74, Dx= 1·754 Mg m-3, CuKa, l = 1·5418 A, ,u = 5·07 mm-1, T= 298 K, F(OOO) = 752, R = 0·074 for 2091 observed independent intensity data. Crystals were prepared by reacting the K salt of ureidotaurine with ninhydrin in acid solution. The product shows that the unsubstituted N -of the ureidotaurine reacts with the central C of ninhydrin

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Cerebral Glutamine/Glutamate Interrelationships And Metabolic Compartmentation / S. Berl And D. D. Clarke, Soll Berl, Donald Dudley Clarke Phd Jan 1984

Cerebral Glutamine/Glutamate Interrelationships And Metabolic Compartmentation / S. Berl And D. D. Clarke, Soll Berl, Donald Dudley Clarke Phd

Chemistry Faculty Publications

The fact that in animals the concentration of glutamate and glutamine are higher in brain than in any other tissue initially attracted interest in attempting to understand the function or functions of these amino acids in the central nervous system. They were evidently required for protein synthesis and early studies established their close relationship to the Krebs tricarboxylic acid cycle and energy metabolism in brain. Glutamine formation in brain was also shown to be sensitive to elevations in plasma ammonia levels and to serve as the primary method for detoxifying this substance in brain in contrast to urea formation in …

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Simulation Analyses Of Space Use: Home Range Estimates, Variability, And Sample Size, Marc Bekoff, L. David Mech Jan 1984

Simulation Analyses Of Space Use: Home Range Estimates, Variability, And Sample Size, Marc Bekoff, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations …

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Optics Of Wide Electron Beam Focusing, Zhou Li-Wei Jan 1984

Optics Of Wide Electron Beam Focusing, Zhou Li-Wei

Scanning Electron Microscopy

In the present paper, we have further studied an approach to the theoretical treatment of wide electron beam focusing, based on the application of the theory of focusing fields with arbitrary curved optical axis, considering the initial condition emitted from the cathode surface. It is assumed that the magnetic field vector B will be used instead of the magnetic scalar potential Ω and the electrostatic potential 𝞅 and the magnetic field vector B are known functions either by computation or experimentally in the laboratory system of coordinates. The new approach to the mathematical treatment appears to be a useful method …

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The Application Of The Alternating Procedure Of H.A. Schwarz For Computing Three-Dimensional Electrostatic Fields In Electron-Optical Systems, Christoph H. Schaefer Jan 1984

The Application Of The Alternating Procedure Of H.A. Schwarz For Computing Three-Dimensional Electrostatic Fields In Electron-Optical Systems, Christoph H. Schaefer

Scanning Electron Microscopy

The numerical solution of three-dimensional electrostatic field problems in electron-optical devices with complicated boundaries requires the use of very large and fast computers. A numerical counterpart of the Alternating Procedure by H. A. Schwarz (SAP) makes efficient use of both storage space and time available on the computer and therefore represents a useful new method in this context. In this method. the domain of solution is decomposed into independent subdomains where the appropriate individual methods of solution may be chosen. Correspondingly. the original boundary value problem is decomposed into a sequence of boundary value problems in these subdomains. SAP requires …

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Constrained Optimization Design Of An Electron Optical System, Chang-Xin Gu, Li-Ying Shan Jan 1984

Constrained Optimization Design Of An Electron Optical System, Chang-Xin Gu, Li-Ying Shan

Scanning Electron Microscopy

An electron optical system can be optimized using the "simplex method" or "complex method". By these methods, the final structure of an electron optical system, for example, an extended field lens (EFL), can be searched with a criterion of minimum objective parameter (in the present case, the coefficient of spherical aberration). Because there is no constraint in the simplex method, the constrained optimization method (the complex method) described in this paper is better than the simplex method in the design of electron optical systems. In the simplex method as well as the complex method, it is not necessary to know …

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Study Of Space Charge Limitation Of Thermionic Cathodes In Triode Guns, A. Delâge, P. B. Sewell Jan 1984

Study Of Space Charge Limitation Of Thermionic Cathodes In Triode Guns, A. Delâge, P. B. Sewell

Scanning Electron Microscopy

A computer program has been developed to compute the emission of cathodes from the fully space charge limited diode equation. The emission of four different gun arrangements with thermionic cathodes of the type used in electron microscopes is investigated. Microflat cathodes with a small (≤50𝜇m in diameter) fixed emitting area show several advantages for high brightness possibilities whereas other types of cathodes for which the emitting area increases with the brightness are usually limited by too great a total emission.

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Aeromonas Hydrophila And Motile Aeromonad Septicemias Of Fish, Rocco C. Cipriano, G. L. Bullock, S. W. Pyle Jan 1984

Aeromonas Hydrophila And Motile Aeromonad Septicemias Of Fish, Rocco C. Cipriano, G. L. Bullock, S. W. Pyle

United States Fish and Wildlife Service: Publications

Aeromonas hydrophila and other motile aeromonads are among the most common bacteria in freshwater habitats throughout the world, and are frequently associated with severe disease among cultured and feral fishes. Determinations of the etiology of diseases involving aeromonad infections has been complicated by the genetic, biochemical, and antigenic heterogeneity of members of this group. Consequently, motile aeromonads consist of a complex of disease organisms that are associated with bacterial hemorrhagic septicemias in fishes. From descriptions of fish diseases in the early scientific literature, Otte (1963) speculated that septicemic infections in fish caused by motile aeromonads were common throughout Europe during …

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Fisheries Report No 66 - The Fishery For Perth Herring, Nematalosa Vlaminghi (Munro), C F. Chubb, N. G. Hall, R C.J. Lenanton, I. C. Potter Jan 1984

Fisheries Report No 66 - The Fishery For Perth Herring, Nematalosa Vlaminghi (Munro), C F. Chubb, N. G. Hall, R C.J. Lenanton, I. C. Potter

Fisheries Research Reports

Perth herring fishery over the last 30 years have been examined. While there are pockets of catches between Broome and Bunbury, those from the Swan Estuary and nearby inshore marine waters make by far the most important contribution to the fishery. In the Swan Estuary, the catches started rising in the 1950s in response to a demand by the rock lobster industry for bait and reached peak values in the late 1960s and early 1970s. Data are provided which demonstrate that catch per boat is a good index of catch per unit effort (CPUE) in the period since 1967 when …

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Contributions To The Genetics Of Tribolium (Coleoptera: Tenebrionidae), Aaron Brownlee Jan 1984

Contributions To The Genetics Of Tribolium (Coleoptera: Tenebrionidae), Aaron Brownlee

Theses Digitization Project

No abstract provided.

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New Species Of Pectis (Asteraceae) From The West Indies, Mexico, And South America, David J. Keil Jan 1984

New Species Of Pectis (Asteraceae) From The West Indies, Mexico, And South America, David J. Keil

Biological Sciences

Four new species of Peetis are described: P. ericifolia from Barbuda, P. luckoviae from west-central Mexico, P. arida from Ecuador and Peru, and P. cajamarcana from Peru. Chromosome counts for P. erieifolza (n = 48) and P. luekoviae (n = 12) are presented. Relationships of the newly described taxa are discussed.

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Thermionic Emission Studies Of Micro-Flat Single Crystal Lanthanum Hexaboride Cathodes, P. B. Sewell, A. Delâge Jan 1984

Thermionic Emission Studies Of Micro-Flat Single Crystal Lanthanum Hexaboride Cathodes, P. B. Sewell, A. Delâge

Scanning Electron Microscopy

A new type of high brightness thermionic cathode has been developed. The cathode utilises emission from a small flat surface (generally less than 50 μm diameter) prepared parallel to a specific crystal plane on a single crystal of Lanthanum Hexaboride. Emission from the rest of the single crystal is suppressed by the use of a high work function coating of pyrolytic graphite. When used in a conventional triode gun, the maximum total electron emission is controlled by the area of the micro-flat, the work function and the temperature of the emitter. The Wehnelt potential serves a minor role in controlling …

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Microchannel Plates As Specialized Scanning Electron Microscopy Detectors, P. E. Russell Jan 1984

Microchannel Plates As Specialized Scanning Electron Microscopy Detectors, P. E. Russell

Scanning Electron Microscopy

The need for a specialized detector for low beam voltage and low beam current applications has led to the investigation of a microchannel plate detector for SEM. The application requirements are described in detail, with the case of integrated circuit metrology used as an example. The microchannel plate (MCP) detector has proven to meet almost all of the design objectives of a low voltage metrology SEM detector. The symmetry of the detector and the ability to mount it directly to the final pole piece are among the most important features.

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Wood Anatomy Of Some Gentianaceae, Sherwin Carlquist Jan 1984

Wood Anatomy Of Some Gentianaceae, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

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Toward A Concise Definition And Perspective For Biology, Arthur V. Brown, Kristine Basinger Brown Jan 1984

Toward A Concise Definition And Perspective For Biology, Arthur V. Brown, Kristine Basinger Brown

Journal of the Arkansas Academy of Science

The content of introductory biology courses at the high school and college levels are currently being re-examined. Many biological educators favor revision of the high school biology courses to a format that directly addresses current social issues to "promote good citizenship". We believe it would be more meaningful to teach the fundamental principles of biology, the study of living systems. Properly defining biology, by defining a living system, should help identify important topics to include in a basic biology course. Emphasis should be placed on subjects which would contribute most to the development of a basic understanding of how all …

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Effects Of Commercial Fish Removal On Sport Fish Populations In Two Arkansas Reservoirs, Tommie Crawford Jan 1984

Effects Of Commercial Fish Removal On Sport Fish Populations In Two Arkansas Reservoirs, Tommie Crawford

Journal of the Arkansas Academy of Science

Commercial netting occurred October through April, 1971-1976 on Nimrod Lake and from October through April, 1973-1977 on Blue Mountain Lake in west central Arkansas. Using 7.6 cm or larger mesh gill and/or trammel nets, commercial fishermen harvested commercial fishes (buffalofishes [Ictiobus spp.]; common carp [Cyprinus carpio], carpsuckers [Carpiodes spp.]; drum [Aplodinotus grunniens]; gars [Lepisosteus spp.]; suckers [Catostomidae); and catfishes [Ictalurus spp. and Pylodictis olivaris]). During the study period, cove rotenone samples were conducted on an annual basis. Fishes collected were placed into age classes and enumerated. Data were then grouped into general categories (black basses [Micropterus spp], crappie [Pomoxis spp.], …

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Ultraviolet Light Reactivation Of Gamma-Ray Induces Chromosome Aberrations In G1 Phase Xenopus Cells, Susan Kulp, Linda Rogers, H. Gaston Griggs Jan 1984

Ultraviolet Light Reactivation Of Gamma-Ray Induces Chromosome Aberrations In G1 Phase Xenopus Cells, Susan Kulp, Linda Rogers, H. Gaston Griggs

Journal of the Arkansas Academy of Science

No abstract provided.

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Summary Account Of The Carolina Parakeet In Arkansas, Daniel Mckinley, Douglas A. James Jan 1984

Summary Account Of The Carolina Parakeet In Arkansas, Daniel Mckinley, Douglas A. James

Journal of the Arkansas Academy of Science

The extinct Carolina Parakeet (Conuropsis carolinensis) once was part of the Arkansas avifauna. The first two reports of the species in what is now Arkansas were made in 1673 and 1718 by early French explorers. The remaining records are from the 1800s when parakeets were found in nearly all parts of the state, often in abundance. The last literature reference for the species still definitely occurring in Arkansas pertains to birds present in the summer of 1885 along the White River at Newport

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