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Peak Force And Maximal Shortening Velocity Of Soleus Fibers After Non-Weight-Bearing And Resistance Exercise, Jeffrey J. Widrick, Robert H. Fitts Jan 1997

Peak Force And Maximal Shortening Velocity Of Soleus Fibers After Non-Weight-Bearing And Resistance Exercise, Jeffrey J. Widrick, Robert H. Fitts

Biological Sciences Faculty Research and Publications

Widrick, Jeffrey J., and Robert H. Fitts. Peak force and maximal shortening velocity of soleus fibers after non-weight-bearing and resistance exercise. J. Appl. Physiol. 82(1): 189–195, 1997.—This study examined the effectiveness of resistance exercise as a countermeasure to non-weight-bearing-induced alterations in the absolute peak force, normalized peak force (force/fiber cross-sectional area), peak stiffness, and maximal shortening velocity (V o) of single permeabilized type I soleus muscle fibers. Adult rats were subjected to one of the following treatments: normal weight bearing (WB), non-weight bearing (NWB), or NWB with exercise treatments (NWB+Ex). The hindlimbs of the NWB and NWB+Ex rats were …


Contractile Properties Of Rat, Rhesus Monkey, And Human Type I Muscle Fibers, Jeffrey J. Widrick, Janell Romatowski, M. Karhanek, Robert H. Fitts Jan 1997

Contractile Properties Of Rat, Rhesus Monkey, And Human Type I Muscle Fibers, Jeffrey J. Widrick, Janell Romatowski, M. Karhanek, Robert H. Fitts

Biological Sciences Faculty Research and Publications

It is well known that skeletal muscle intrinsic maximal shortening velocity is inversely related to species body mass. However, there is uncertainty regarding the relationship between the contractile properties of muscle fibers obtained from commonly studied laboratory animals and those obtained from humans. In this study we determined the contractile properties of single chemically skinned fibers prepared from rat, rhesus monkey, and human soleus and gastrocnemius muscle samples under identical experimental conditions. All fibers used for analysis expressed type I myosin heavy chain as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Allometric coefficients for type I fibers from each muscle …


The Stabilizing Efects Of Disulfide Bonds On Limulus And Octopus Hemocyanin, Danielle Mercatante Jan 1997

The Stabilizing Efects Of Disulfide Bonds On Limulus And Octopus Hemocyanin, Danielle Mercatante

Honors Theses

Hemocyanin is a large molecular weight, oxygen carrying protein that is present in the hemolymph of mollusks and arthropods . Limulus, horseshoe crab, hemocyanin is made up of 48 hexamer subunits ( consisting of seven different repeating subunits) each of which have oxygen binding dinuclear copper active centers. Octopus hemocyanin is composed of a single kind of polypeptide chain that has seven functional units, or oxygen binding domains.

The goals of research conducted by Gregory Cole and Danielle Mercatante during the fall of 1996 and spring of 1997 were to gain a biochemical understanding of the structure of Limulus and …


Acute And Chronic Exposure To Lead: Cellular And Behavioral Effects On The Pond Snail Helisoma Trivolvis, Virginia T. Bennett Jan 1997

Acute And Chronic Exposure To Lead: Cellular And Behavioral Effects On The Pond Snail Helisoma Trivolvis, Virginia T. Bennett

College of Graduate Studies: Theses & Dissertations (1964–2006)

The focus of this study is on the effects of lead on Helisoma trivolvis, a pulmonate pond snail. Many species of molluscs are being used as bioindicators of environmental toxins. To provide a background for the reader, a brief history and description of the Phylum Mollusca (at the class level) is presented in Chapter 1. A second chapter (Ch. 2) is concerned with lead and its effects. A synopsis of past and present studies that show the interaction between lead and molluscs is given in Chapter 3, then two experimental chapters follow. The first experimental chapter (Ch. 4) is …


Small Miracles: Propagation Efforts Using Plants In The Family Hamamelidaceae, Martha Sasser Joiner Jan 1997

Small Miracles: Propagation Efforts Using Plants In The Family Hamamelidaceae, Martha Sasser Joiner

College of Graduate Studies: Theses & Dissertations (1964–2006)

Attempts were made to propagate five species in the family Hamamelidaceae by softwood cuttings or seeds. Local populations of witch-hazel Hamamelis virginiana L. and sweetgum Liquidambar styraciflua L. supplied cuttings and seeds of these native American species. Cultivated plants of dwarf witch-alder Fothergilla gardenii Murray were used initially for cuttings. Later, three native populations of this species were located and cuttings were obtained from them. Also, for seed propagation studies, seeds of F. gardenii were obtained from the North Carolina Botanical Garden and seeds were obtained from cultivated plants of two Asian species, winter hazel Corylopsis sinensis Hemsley and Chinese …


Internal Oral Anatomy: A Comparative Analysis Of The Phyllomedusinae (Anura:Hylidae), Erin B. Hines Jan 1997

Internal Oral Anatomy: A Comparative Analysis Of The Phyllomedusinae (Anura:Hylidae), Erin B. Hines

Honors Theses

The internal oral anatomy of phyllomedusines has only been described for Agalychnis callydrias using light microscopy. Herein, we compare the internal oral anatomy of the genera Phyllomedusa, Agalychnis, Pachymedusa, and Phasmahyla, using SEM methodology. Tadpoles of ten species were prepared using standard SEM techniques; these larvae ranged from Gosner stages 34-39. Phasmahyla has a unique prenarial arena with three well developed pre-narial arena papillae, whereas the other genera possess the prenarial arena papillae in a semicircular arrangement with the opening directed posteriorly. Pachymedusa differs from Phyllomedusa and Agalychnis by having a low, straight-edge, median ridge; also, its buccal floor arena …


Ubiquitin-Mediated Proteolysis During Gametogenis In Chlamydomonas Reinhardtii, Hall Thomas Mcgee Jan 1997

Ubiquitin-Mediated Proteolysis During Gametogenis In Chlamydomonas Reinhardtii, Hall Thomas Mcgee

Honors Theses

Scientists in the field of cell biology have focused considerable attention on a unicellular species of green algae known as Chlamydomonas reinhardtii. This organism is relatively common in bodies of fresh water and some types of soil, but most of the attention is due to its value as a model for biochemical studies. This laboratory has undertaken a broad study of the species including exploration into a special class of proteins, called heat shock proteins, and certain biochemical processes of the organism. The work herein described is a part of this latter study, and also a preliminary step in a …


Preservation Of Community Structure In Death Assemblages Of Deep‐Water Caribbean Reef Corals, John M. Pandolfi, Benjamin J. Greenstein Jan 1997

Preservation Of Community Structure In Death Assemblages Of Deep‐Water Caribbean Reef Corals, John M. Pandolfi, Benjamin J. Greenstein

Arts & Sciences Faculty Publications

An in situ survey of deep reef environments (20 and 30 m) was conducted to determine the degree to which the community structure of live reef coral assemblages was faithfully represented in the adjacent death assemblages accumulating on the sea floor. Relative abundance of species was significantly different between life and death assemblages, and zonation patterns (in species relative abundance, coral growth form, and diversity) present in the life assemblages showed both similarities and differences to those found in the death assemblages. The difference in species distribution patterns between life and death assemblages is shown by a striking growth form …


Relationship Between Yeast Polyribosomes And Upf Proteins Required For Nonsense Mrna Decay, Audrey L. Atkin, Laura R. Schenkman, Margot Eastham, Jeffrey N. Dahlseid, Michael J. Lelivelt, Michael R. Culbertson Jan 1997

Relationship Between Yeast Polyribosomes And Upf Proteins Required For Nonsense Mrna Decay, Audrey L. Atkin, Laura R. Schenkman, Margot Eastham, Jeffrey N. Dahlseid, Michael J. Lelivelt, Michael R. Culbertson

School of Biological Sciences: Faculty Publications

In yeast, the accelerated rate of decay of nonsense mutant mRNAs, called nonsense-mediated mRNA decay, requires three proteins, Upf1p, Upf2p, and Upf3p. Single, double, and triple disruptions of the UPF genes had nearly identical effects on nonsense mRNA accumulation, suggesting that the encoded proteins function in a common pathway. We examined the distribution of epitope-tagged versions of Upf proteins by sucrose density gradient fractionation of soluble lysates and found that all three proteins co-distributed with 80 S ribosomal particles and polyribosomes. Treatment of ly-sates with RNase A caused a coincident collapse of polyribosomes and each Upf protein into frac-tions containing …


Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva Jan 1997

Description Of The Tadpole Of Atelopus Tricolor, E. O. Lavilla, Rafael O. De Sá, Ignacio De La Riva

Biology Faculty Publications

Tadpoles of Atelopus belong to the gastromyzophorous guild of exotrophic larvae (Altig and Johnston, 1989), and are characterized by the presence of a conspicuous abdominal sucker and an expanded oral disc. The larvae of several Atelopus species have been described previously: A. varius (Starrett, 1967); A. certus, A. ignescens, and A. spumarius (Duellman and Lynch, 1969); A. cruciger (Mebs, 1980); A. flavescens (Lescure, 1981); A. peruensis (Gray and Cannatella, 1985); and A. subornatus (Lynch, 1986). These represent about 15% of the known species in the genus (Frost, 1985; Duellman, 1993). Although Atelopus tricolor was originally described at the beginning of …


Evaluation Of The Effects Of Afff Inputs On The Vip Biological Nutrient Removal Process And Pass-Through Toxicity. Phase 1a. Volume Ii. Appendix Vii. Acute Toxicity Test Results, Mujde Erten-Unal, Gary C. Schafran Jan 1997

Evaluation Of The Effects Of Afff Inputs On The Vip Biological Nutrient Removal Process And Pass-Through Toxicity. Phase 1a. Volume Ii. Appendix Vii. Acute Toxicity Test Results, Mujde Erten-Unal, Gary C. Schafran

Civil & Environmental Engineering Faculty Publications

This report discusses the results of a bench scale study conducted to evaluate the potential inhibitory effects of untreated AFFF wastewater to the Virginia Initiative Plant VIP biological nutrient removal process. A bench-scale study was conducted to evaluate the potential inhibitory effects of untreated AFFF wastewater to the nitrification process of the Virginia Initiative Plant biological nutrient removal system. Under this testing, bench-scale reactors simulating the nitrification process were loaded at various AFFF concentrations and the influence on the process performance was evaluated. The purpose of this effort was to determine the level of AFFF that could be incorporated into …


Description Of Tadpoles Of Three Species Of Scinax (Anura: Hylidae), Rafael O. De Sá, Rocjard Wassersig, Arturo I. Kehr Jan 1997

Description Of Tadpoles Of Three Species Of Scinax (Anura: Hylidae), Rafael O. De Sá, Rocjard Wassersig, Arturo I. Kehr

Biology Faculty Publications

Larval morphological characteristics have been used to cluster species of Scinax in seven species groups and to support the monophyly of some of these groups. However, our present knowledge of Scinax tadpoles is incomplete; currently, tadpoles of only 21 of the approximately 80 recognized species have been described. Herein, we describe and illustrate the external morphology and oral disc characteristics of larval Scinax berthae, S. nebulosa, and S. boesemani. The presence of a "labial arm" supporting the P3 tooth row in S. boesemani, and its absence from S. nebulosa, is discussed in the light of our limited knowledge of tadpoles …


Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones Jan 1997

Law And Biology: Toward An Integrated Model Of Human Behavior, Owen D. Jones

Vanderbilt Law School Faculty Publications

As first year law students unhappily discover, the meaning of "law" is frustratingly protean, shifting by usage and user. Depending on whom you ask, law is a system of rules, a body of precedents, a legislative enactment, a collection of norms, a process by which social goals are pursued, or some dynamic mixture of these. Law's principal purpose is to define and protect individual rights, to ensure public order, to resolve disputes, to redistribute wealth, to dispense justice, to prevent or compensate for injury, to optimize economic efficiency, or perhaps to do something else. And yet one thing is irreducibly …


" The African And Madagascan Freshwater Crabs In The Museum Of Natural History, Vienna" , Neil Cumberlidge Jan 1997

" The African And Madagascan Freshwater Crabs In The Museum Of Natural History, Vienna" , Neil Cumberlidge

Journal Articles

No abstract provided.


The Effects Of Adrenergic And Cholinergic Stimulation On Skin Gland Secretions In The Dwarf African Frog Hymenochirus Curtipes, Daniel H. Gong Jan 1997

The Effects Of Adrenergic And Cholinergic Stimulation On Skin Gland Secretions In The Dwarf African Frog Hymenochirus Curtipes, Daniel H. Gong

University of the Pacific Theses and Dissertations

Many studies have been done on the neural control of serous gland secretion in the skin of frogs and newts. However, no studies have been published on the effects of adrenergic and cholinergic neurotransmitters on the sexually dimorphic breeding glands of male frogs. The present study examined the effects of neurotransmitters on the serous and breeding glands of Hymenochirus curtipes. Explants of dorsal skin and postaxial skin (containing whole breeding glands) were incubated in vitro with epinephrine, norepinephrine or acetylcholine for 30 minutes. The explants were then preserved and examined histologically for signs of secretion. The area and perimeter of …


Role Of Calcium And Other Cations On Contractile Vacuole Activity Of Tetrahymena Thermophila, Robert William Bird Jan 1997

Role Of Calcium And Other Cations On Contractile Vacuole Activity Of Tetrahymena Thermophila, Robert William Bird

Dissertations and Theses @ UNI

The contractile vacuole (CV) of Tetrahymena removes fluids from the cell and maintains cellular integrity. Although many studies have been done, it is not fully understood what controls its function. Therefore, this study sought to further elucidate an understanding of what controls the activity of the CV. The effect of calcium on CV activity was studied. Twenty-four hour cultures of Tetrahymena were centrifuged, washed in an experimental solution and isolated. Single cells were measured and analyzed using computer video imaging and analysis programs. Compared to control cells, cells treated with calcium have statistically significant differences (P < 0.00001) in the following parameters: smaller overall cell volume, CV volume, and the interval between contractions. Calcium has an effect on CV activity. Increases in calcium result in decreases in cell volume and CV volume. Cadmium treated cells differed (P < 0.00001) from control cells in cell volume, CV volume, kinetics (slope) of contraction, and the interval between contractions. Increases in cadmium, relative to calcium, result in increased cell and CV volumes. Taken together, these results indicate that the control of CV activity in Tetrahymena is through stretch-activated ion selective calcium channels.


Understanding Of Wetlands As Expressed By Selected Community Leaders, Donald Nathan Bardole Jan 1997

Understanding Of Wetlands As Expressed By Selected Community Leaders, Donald Nathan Bardole

Dissertations and Theses @ UNI

This study focuses on ascertaining the understanding of wetlands by selected community and state leaders and determining the source of that knowledge. Because of the subjects' positions of influence, this information may become an important element in understanding the decisions made by those community and state leaders. An interview survey was designed and piloted for this study. Community and state leadership positions were first delineated and then individuals selected from each category. The subjects varied considerably in their knowledge of wetlands, showed the presence of professional expediency, and agreed that regulation in some form is necessary. The wetlands knowledge held …


The Roles Of Harsh And Fluctuating Conditions In The Dynamics Of Cological Communities, P Chesson, Nancy J. Huntly Jan 1997

The Roles Of Harsh And Fluctuating Conditions In The Dynamics Of Cological Communities, P Chesson, Nancy J. Huntly

Biology Faculty Publications

Harsh conditions (e.g., mortality and stress) reduce population growth rates directly; secondarily, they may reduce the intensity of interactions between organisms. Near-exclusive focus on the secondary effect of these forms of harshness has led ecologists to believe that they reduce the importance of ecological interactions, such as competition, and favor coexistence of even ecologically very similar species. By examining both the costs and the benefits, we show that harshness alone does not lessen the importance of species interactions or limit their role in community structure. Species coexistence requires niche differences, and harshness does not in itself make coexistence more likely. …


Investigation Of Transactivation Of The Human C-Myc Gene By Herpes Simplex Virus Type 1, Xian Wu Jan 1997

Investigation Of Transactivation Of The Human C-Myc Gene By Herpes Simplex Virus Type 1, Xian Wu

Dissertations and Theses

The purpose of this investigation was to identify the regulatory elements involved in the transactivation of the human c-myc gene by herpes simplex virus type-1 (HSV-1). This study mainly focused on a major c-myc promoter P2 (Fig. 1). Transient expression assays were carried out with a reporter plasmid, that contained either a wild type (+66wt c-myc) or mutant (+66 mt E2F, +66mt CT -I2) c-myc promoter fused to the chloramphenicol acetyltransferase (CAT) gene, cotransfected with effector plasmids that contained the HSV-1 immediate early (IE) genes ( encoding IE proteins, ICP4, ICP0, ICP27). The transient expression assays revealed …


Evidence That Elevated C02 Levels And Indirectly Increase Rhizosphere Denitrifier Activity, John M. Stark, D. Smart, K. Ritchie, Bruce Bugbee Jan 1997

Evidence That Elevated C02 Levels And Indirectly Increase Rhizosphere Denitrifier Activity, John M. Stark, D. Smart, K. Ritchie, Bruce Bugbee

Biology Faculty Publications

We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier …


Analysis Of The Inheritance Repression Of A Transposable Element In Drosophila Melanogaster, Melissa Leone Jan 1997

Analysis Of The Inheritance Repression Of A Transposable Element In Drosophila Melanogaster, Melissa Leone

Master's Theses

No abstract provided.


Benthic Invertebrate Community Responses To Round Goby (Neogobius Melanostomus) And Zebra Mussel (Dreissena Polymorpha) Invasion In Southern Lake Michigan, Linda A. Benning Jan 1997

Benthic Invertebrate Community Responses To Round Goby (Neogobius Melanostomus) And Zebra Mussel (Dreissena Polymorpha) Invasion In Southern Lake Michigan, Linda A. Benning

Master's Theses

No abstract provided.


Characterization Of Deletion Sites In A Human Collagen-Like Locus, Marissa A. Michaels Jan 1997

Characterization Of Deletion Sites In A Human Collagen-Like Locus, Marissa A. Michaels

Master's Theses

No abstract provided.


Regulation Of The Activities Of The Three Nitrate Reductase Isoforms In Wild-Type Soybean Glycine Max (L.) Merr. (Variety Williams) By Protein Phosphorylation, Maribel T. Joson Jan 1997

Regulation Of The Activities Of The Three Nitrate Reductase Isoforms In Wild-Type Soybean Glycine Max (L.) Merr. (Variety Williams) By Protein Phosphorylation, Maribel T. Joson

Master's Theses

No abstract provided.


Saccharomyces Cerevisiae-Produced Recombinant Pfs230: A Malaria Transmission-Blocking Vaccine Candidate, Kathryn M. Glynn Jan 1997

Saccharomyces Cerevisiae-Produced Recombinant Pfs230: A Malaria Transmission-Blocking Vaccine Candidate, Kathryn M. Glynn

Master's Theses

No abstract provided.


Observations On The Body Temperatures And Natural History Of Same Mexican Reptiles, J. A. Lemos-Espinal, Geoffrey R. Smith, R. E. Ballinger Jan 1997

Observations On The Body Temperatures And Natural History Of Same Mexican Reptiles, J. A. Lemos-Espinal, Geoffrey R. Smith, R. E. Ballinger

Faculty Publications

No abstract provided.


The Effects Of Aeration On Amphibian Larval Growth: An Experiment With Bullfrog Tadpoles, Geoffrey R. Smith Jan 1997

The Effects Of Aeration On Amphibian Larval Growth: An Experiment With Bullfrog Tadpoles, Geoffrey R. Smith

Faculty Publications

No abstract provided.


Interactive Effects Of Aluminum And Humic Substances On Salvinia, Jeffrey L. Gardner, Safaa H. Al-Hamdani Jan 1997

Interactive Effects Of Aluminum And Humic Substances On Salvinia, Jeffrey L. Gardner, Safaa H. Al-Hamdani

Research, Publications & Creative Work

Salvinia increased the pH of the growth media within two days to near neutral pH in the absence of Al with and without humic substances. In most cases, Al in the absence of humic substances reduced salvinia growth, chlorophyll a and b concentrations, and carotenoid concentrations. Reductions were greater with increasing concentrations of Al and humic substances alleviated some of the toxic effects of Al. Also, corrected treatments (pH 3.9) influenced an increase in the above parameters for most treatments compared to uncorrected treatments (pH varied according to the treatment). Anthocyanin concentrations of salvinia increased in treatments receiving Al. The …


Macrophyte-Macroinvertebrate Interactions In A Lentic Ecosystem And The Effect Of Fluridone Treatment To Control Myriophyllum Spicatum L., Gregory J. Moeller Jan 1997

Macrophyte-Macroinvertebrate Interactions In A Lentic Ecosystem And The Effect Of Fluridone Treatment To Control Myriophyllum Spicatum L., Gregory J. Moeller

Dissertations and Theses @ UNI

Myriophyllum spicatum L. is an exotic macrophyte that can become pestiferous in lentic ecosystems. Two field studies were conducted to investigate: 1) epiphytic macroinvertebrates associated with M. spicatum and native macrophytes; and 2) epiphytic macroinvertebrate community response to fluridone treatment for M. spicatum control.

In the first study evaluating epiphytic macroinvertebrates associated with M. spicatum and native macrophytes, triplicate samples were collected at three sites in both Auburn and Zumbra Lakes, Minnesota, USA. One site in each lake contained primarily M. spicatum, the second site contained M. spicatum and native vegetation, and the third site was dominated by native …


Ecomorphology Of Peromyscus In Iowa, Frederick Dramani Biga Jan 1997

Ecomorphology Of Peromyscus In Iowa, Frederick Dramani Biga

Dissertations and Theses @ UNI

Deer mice (Peromyscus maniculatus bairdii) and white-footed mice (Peromyscus /eucopus noveboracensis) were collected from weedy and prairie habitats of Black Hawk County, and white-footed mice were collected from forested areas of Hardin County, Iowa. Twenty-three external and cranial characters were measured from 125 deer mice and 72 white-footed mice. Analysis of means by t-tests showed significant sexual dimorphism in deer mice in four cranial characters; palatine width at 3rd molar, width of foramen magnum, width of 3rd molar, and width of the incisor. Sexual dimorphism was also found in white-footed mice in three external and one cranial character: total length, …