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Articles 18841 - 18870 of 20606
Full-Text Articles in Entire DC Network
A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver
A Review Of The Biology Of Giant Salvinia, J. Douglas Oliver
Faculty Publications and Presentations
Giant salvinia (Salviniaceae) is a potentially serious aquatic weed that is native to Brazil. It has been reported in more than 20 countries, but is not established in the U.S. at this time. Mitchell and Tur (1975) reported that three years after the formation of the Kariba Reservoir in Africa, giant salvinia blanketed 21.5% or 1003 km2 of the reservoir surface area. Creagh (199111992) wrote, "A single small plant may grow to form a thick mat covering more than 100 sq. km. in just three months - choking lakes and waterways, reducing populations of aquatic plants and animals and in …
Ultrastructure Of The Coeloms Of Auricularia Larval (Holothuroidea Echinodermata): Evidence For The Presence Of An Axocoel, E. J. Balser, E. E. Ruppert, William Jaeckle
Ultrastructure Of The Coeloms Of Auricularia Larval (Holothuroidea Echinodermata): Evidence For The Presence Of An Axocoel, E. J. Balser, E. E. Ruppert, William Jaeckle
Scholarship
A hallmark feature of echinoderm larvae is the development of the left anterior coelom. This coelom, called the axohydrocoel, consists of the morphologically distinct, but undivided, left axocel and hydrocel. The axocoelic portion forms a duct that opens to the exterior via a pore on the dorsal surface of the animal. Holothuroid larvae are thought to lack an axocoel, but develop an anterior coelom, duct, and pore that are regarded as parts of the hydrocoel. New ultrastructural data, however, show that holothuroid auricularia larvae possess an axocel and hydrocel united together into an axohydrocoel. During development the anterior coelom consists …
Acid-Base Regulation In Three Marine Teleosts: The Oyster Toadfish (Opsanus Tau), The Winter Flounder (Pseudopleuronectes Americanus), And The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Dana Compton Mccullough
Acid-Base Regulation In Three Marine Teleosts: The Oyster Toadfish (Opsanus Tau), The Winter Flounder (Pseudopleuronectes Americanus), And The Long-Horned Sculpin (Myoxocephalus Octodecimspinosus), Dana Compton Mccullough
College of Graduate Studies: Theses & Dissertations (1964–2006)
In this study, three species of marine fish were exposed to a variety of dilute salinities in order to determine what effects exposure to diluted seawater may have on acid-base and ion balance. The oyster toadfish (Opsanus tau) and the winter flounder (Pseudopleuronectes americanus) are considered to be able to live in a broad range of salinities, euryhaline (Evans, 1979). The long-homed sculpin, Myoxocephalus octodecimspinosus, is considered to be a stenohaline fish, not able to withstand drastic changes in ambient salinity (Claibome and Evans, 1988).
Initially, toadfish exposed to 20 mM diluted seawater took up …
Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, John C. Larkin, David G. Oppenheimer, Susan Pollock, M. David Marks
Arabidopsis Glabrous1 Gene Requires Downstream Sequences For Function, John C. Larkin, David G. Oppenheimer, Susan Pollock, M. David Marks
School of Biological Sciences: Faculty Publications
The Arabidopsis GLABROUSl (GL1) gene is a myb gene homolog required for the initiation of trichome development. In situ hybridiration revealed that the highest levels of GL1 transcripts were present in developing trichomes. In contrast, previous work had shown that putative promoter sequences from the 5‘ noncoding region of the GL1 gene directed the expression of a β-glucuronidase (GUS) reporter gene only in stipules. Deletion analysis of the 3’ noncoding region of GL1 has identified an enhancer that is essential for GL1 function. Sequences fmm the region containing the enhancer, in conjunction with GL1 upstream sequences, direct the expression of …
Morfología Y Moléculas: Bases Complementarias De La Sistemática Moderna, Rafael O. De Sá, David M. Hillis
Morfología Y Moléculas: Bases Complementarias De La Sistemática Moderna, Rafael O. De Sá, David M. Hillis
Biology Faculty Publications
RESUMEN
El auge de las técnicas moleculares en las últimas dos décadas ha traído nuevos enfoques en los estudios sistemáticos. Aquí presentaremos una revisión del uso, las aplicaciones, y los problemas de las principales metodologías de trabajo. Cada una de estas técnicas es aplicable a algunos problemas e inapropiada para otros, y es importante entender las suposiciones y limitaciones de cada técnica. Concluimos que el uso combinado de los enfoques morfológicos y moleculares otorga mejor resolución a los problemas sistemáticos.
ABSTRACT
The development of molecular techniques during the last two decades has brought new approaches to the analysis of systematic …
" Further Remarks On The Identification Of Sudanonautes Orthostylis With Comparisons With Other Species From Nigeria And Cameroon" , Neil Cumberlidge
" Further Remarks On The Identification Of Sudanonautes Orthostylis With Comparisons With Other Species From Nigeria And Cameroon" , Neil Cumberlidge
Journal Articles
No abstract provided.
" Two New Species Of Potamonemus Cumberlidge And Clark From The Rain Forests Of West Africa" , Neil Cumberlidge
" Two New Species Of Potamonemus Cumberlidge And Clark From The Rain Forests Of West Africa" , Neil Cumberlidge
Journal Articles
No abstract provided.
"Redescription Of Sudanonautes Granulatus From West Africa" , Neil Cumberlidge
"Redescription Of Sudanonautes Granulatus From West Africa" , Neil Cumberlidge
Journal Articles
No abstract provided.
Effects Of Perinatal Cocaine Exposure On Sexual Differentiation In The Rat Brain, Heather L. Maecker
Effects Of Perinatal Cocaine Exposure On Sexual Differentiation In The Rat Brain, Heather L. Maecker
Master's Theses
No abstract provided.
Biology Of The Palo Alto Battlefield Site: A Summary, Norman L. Richard, Alfred Richardson
Biology Of The Palo Alto Battlefield Site: A Summary, Norman L. Richard, Alfred Richardson
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)
No abstract provided.
Where Environmental Law And Biology Meet: Of Pandas' Thumbs, Statutory Sleepers, And Effective Law, William H. Rodgers, Jr.
Where Environmental Law And Biology Meet: Of Pandas' Thumbs, Statutory Sleepers, And Effective Law, William H. Rodgers, Jr.
Articles
The purpose of this article is to introduce some of the recent findings of evolutionary biology to the legal community and to urge their consideration in developing a more effective law. As background, Part II of this article will present a brief evolutionary history of our own species.
Part III offers a primer on Darwin's theory of natural selection and the concept of adaptation, with special attention to the elaboration of altruism as it is known in modern biology. Part IV discusses maladaptation as a counterpoise to adaptation and underscores the notion with some stories from natural history on subjects …
The Nfiii/Oct-1 Binding Site Stimulates Adenovirus Dna Replication In Vivo And Is Functionally Redundant With Adjacent Sequences, Lianna K. Etchberger, P. Hearing
The Nfiii/Oct-1 Binding Site Stimulates Adenovirus Dna Replication In Vivo And Is Functionally Redundant With Adjacent Sequences, Lianna K. Etchberger, P. Hearing
Biology Faculty Publications
The inverted terminal repeat (ITR) of adenovirus type 5 (Ad5) is 103 bp in length and contains the origin of DNA replication. Cellular transcription factors NFI/CTF and NFIII/OCT-1 bind to sites within the ITR and participate in the initiation of viral DNA replication in vitro. The ITR also contains multiple copies of two conserved sequence motifs that bind the cellular transcription factors SP1 and ATF. We have analyzed a series of viruses that carry deletions at the left terminus of Ad5. A virus carrying a deletion of the NFIII/OCT-1, SP1, and ATF sites within the ITR (mutant dl309-44/107) was wild …
Connexin Expression During Heart Development In The Chick Embryo, Lisa Jo Jensen
Connexin Expression During Heart Development In The Chick Embryo, Lisa Jo Jensen
Dissertations and Theses @ UNI
Gap junctions are thought to be important during development because they interconnect cells for communication via signaling molecules. In the developmental process, the heart is coupled via gap junctions. The heart has many migratory, proliferative, and differentiation events in which gap junctions may serve a central role in development. The goal of this study was to measure the connexin levels throughout selected stages of cardiac development and to ascertain the normal connexin levels to use as comparisons in experimental systems such as microgravity. This study measured the amount of connexin protein in the embryonic heart at 1.5-, 2-, 3-, 4-, …
Determinants Of Success In Experimental Introductions Of The Rodent (Mus Musculus) Onto Habitat Islands, Mark W. Krissinger
Determinants Of Success In Experimental Introductions Of The Rodent (Mus Musculus) Onto Habitat Islands, Mark W. Krissinger
College of Graduate Studies: Theses & Dissertations (1964–2006)
I conducted an experimental test of the influence of supplemental food on persistence time of intentionally introduced (i.e. translocated) mice (Mus musculus) on four habitat islands. I determined the species composition of small mammals in the four insular patches of habitat (i.e. habitat islands) formed by Interstate Highway 16 and associated access roads at the US Hwy 301 interchange using standard live-trapping methods. Two of the habitat islands supported three resident rodent species, whereas the other two each supported one species.
After determining the initial species composition of the four habitat islands I released 14 uniquely marked individuals …
A Study Of Science Teacher Perceptions And The Implementation Of Science-Technology-Society Education In Iowa Senior High Schools, David L. Johnson
A Study Of Science Teacher Perceptions And The Implementation Of Science-Technology-Society Education In Iowa Senior High Schools, David L. Johnson
Dissertations and Theses @ UNI
The purpose of this study was to determine the extent to which Science-Technology Society (STS) education has been implemented into the science curriculum and if teachers perceptions and personal assessment of STS education in Iowa senior high schools vary with the teacher's STS background or educational degree. Consisting of 190 senior high school science teachers (grades 9-12) in forty-nine schools distributed throughout the state of Iowa, the sample was obtained by a systematic, stratified sampling of school districts by enrollment size and Area Education Agency districts. Teachers were asked to complete questionnaires designed to collect data concerning: STS background, level …
Live Northern Harrier Entrapped In Ice, Given Harper, Thomas Dunstan
Live Northern Harrier Entrapped In Ice, Given Harper, Thomas Dunstan
Scholarship
No abstract provided.
Calcospherites In Rabbit Incisor Predentin, H. Mishima, Y. Kunuki, T. Sakae, Y. Kozawa, N. Watabe
Calcospherites In Rabbit Incisor Predentin, H. Mishima, Y. Kunuki, T. Sakae, Y. Kozawa, N. Watabe
Scanning Microscopy
Calcospherites from the lower incisor dentin of rabbits were investigated by scanning and transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and electron diffraction analyses. In the labial predentin, globular calcospherites of 8-31 μm were present at the root apex, decreasing in size toward the incisal region. The calcospherites at the intermediate region were of mulberry- as well as of spindle-shape of 1.5-4 μm diameter. The incisal pulp horn contained micro-calcospherites of 0.3-0.6 μmin diameter. In the lingual predentin, small granular calcospherites of 1. 8-3 μm were present at the root apex, increasing in size toward the intermediate region. Ultrathin …
Ultrastructural Features Of Human Reissner's Membrane, Anne De Fraissinette, Heidi Felix, Jannie Nievergelt, Michael Gleeson
Ultrastructural Features Of Human Reissner's Membrane, Anne De Fraissinette, Heidi Felix, Jannie Nievergelt, Michael Gleeson
Scanning Microscopy
Ultrastructural features of human Reissner' s membrane were investigated in two groups of similarly aged patients. Five patients had age-related normal hearing (ARNH) and four patients had acquired sensorineural hearing loss (SNHL) from causes other than age. The membrane consisted of a mesothelium facing the perilymph and an epithelium facing the endolymph. The two cell layers were separated by a basement membrane. The mesothelium was formed by wide spread thin cells with a smooth surface. The epithelial cells assumed two different shapes, flat and rounded. Both epithelial cell types were covered with many short microvilli. In all specimens, the rounded …
Recent Advances In Measurement Of Oxalate In Biological Materials, S. Sharma, R. Nath, S. K. Thind
Recent Advances In Measurement Of Oxalate In Biological Materials, S. Sharma, R. Nath, S. K. Thind
Scanning Microscopy
Hyperoxaluria is the predominant risk factor in urinary stone disease. A specific, accurate and reliable oxalate assay for urine and plasma is very important for both the diagnosis and efficient management of patients. A review of the advantages and disadvantages of various methods of oxalate determination is presented and is followed by the authors' recommendations.
Microvascular Architecture Of The Filiform Papillae In Primates And Insectivores, S. Okada, Y. Ohta, N. Matsukawa, S. Sugioka
Microvascular Architecture Of The Filiform Papillae In Primates And Insectivores, S. Okada, Y. Ohta, N. Matsukawa, S. Sugioka
Scanning Microscopy
The microvascular architecture of filiform papillae was investigated under a scanning electron microscope in man, Japanese monkeys, common squirrel monkeys, common marmosets, common tree shrews, large Japanese moles and dwarf shrews utilizing microvascular corrosion casts. Filiform papillae were circularly arranged in primates, and each of them was supplied by a hairpin capillary loop. These papillae sometimes were aggregated. The filiform papillae of Japanese monkeys exhibited markedly locational differences on the lingual dorsum and were supplied by circularly arranged capillary loops or by an intrapapillary capillary network. Small filiform papillae were located on an epithelial eminence in the lingual radix, each …
Distribution Of Connectin (Titin) And Transverse Tubules At Myotendinous Junctions, Y. Shimada, F. Atsuta, M. Sonoda, M. Shiozaki, K. Maruyama
Distribution Of Connectin (Titin) And Transverse Tubules At Myotendinous Junctions, Y. Shimada, F. Atsuta, M. Sonoda, M. Shiozaki, K. Maruyama
Scanning Microscopy
The ends of muscle fibers form many longitudinal projections which are further divided into numerous processes and attach to the collagen fibrils of tendons to form myotendinous junctions (MTJs). Immunocytochemical and electron microscopic observations on pectoralis muscles of the chicken revealed the presence of an elastic filamentous protein, connectin (titin), within the terminal sarcomere on the side adjacent to the terminal Z bands, and the absence of connectin and myosin and the presence of actin at the apical sarcoplasmic region of MTJ processes between the terminal Z band and the MTJ sarcolemma. Intermediate voltage electron microscopy showed that T tubules …
Influence Of 17-B-Estradiol And Progesterone On The In Vitro Cultured Mouse Preimplantation Embryos, Matthew L. Offutt
Influence Of 17-B-Estradiol And Progesterone On The In Vitro Cultured Mouse Preimplantation Embryos, Matthew L. Offutt
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Matthew L. Offutt on December 10, 1992.
Cellular Interactions In Hemopoietic Progenitor Cell Homing: A Review, Cheryl L. Hardy, Jose J. Minguell
Cellular Interactions In Hemopoietic Progenitor Cell Homing: A Review, Cheryl L. Hardy, Jose J. Minguell
Scanning Microscopy
Within the bone marrow microenvironment, dynamic cellular interactions are constantly occurring. These interactions involve hemopoietic stem cells, progenitor cells and maturing cells, physically interacting with other cells, some of which may function as accessory cells, and others which comprise the stromal elements; hemopoietic cells also interact with non-cellular elements, such as glycoproteins and fibrous proteins of the extracellular matrix (ECM). These interactions serve to regulate normal hemopoiesis by allowing the communication of regulatory information, migration and subsequent homing of stem cells within specific organs, and presentation of hemopoietic growth factors in a biologically relevant fashion. The goal of this review …
Bacterial Numbers And Activity, Microalgal Biomass And Productivity, And Meiofaunal Distribution In Sediments Naturally Contaminated With Biogenic Bromophenols, Charles C. Steward, James L. Pinckney, Yvette Piceno, Charles R. Lovell
Bacterial Numbers And Activity, Microalgal Biomass And Productivity, And Meiofaunal Distribution In Sediments Naturally Contaminated With Biogenic Bromophenols, Charles C. Steward, James L. Pinckney, Yvette Piceno, Charles R. Lovell
Faculty Publications
Sediment cores were collected inside and outside of a bed of a bromophenol-producing marine polychaete, Notomastus lobatus, and examined for impact of the bromophenols on sediment microflora and meiofauna around N. lobatus burrows. No significant differences were found between microbial parameters measured inside and outside of the N. lobatus bed. Integrated 6 cm cores taken adjacent to N. lobatus burrows contained 1.2 x 109 bacteria ml-1. Cell numbers were similar at control sites within the bed, but away from burrows, and not significantly different from cell numbers (1.0 X 109 cells ml-1) at a …
Sediment-Water Nutrient Flux In Tidal Creeks Of North Inlet, South Carolina, Michael Duane Quillen
Sediment-Water Nutrient Flux In Tidal Creeks Of North Inlet, South Carolina, Michael Duane Quillen
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Arts and Sciences at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Michael Duane Quillen on December 7, 1992.
Retinol Deficiency And Urinary Stone Disease: Clinical Evidence Is Missing, P. P. Singh, R. Kiran
Retinol Deficiency And Urinary Stone Disease: Clinical Evidence Is Missing, P. P. Singh, R. Kiran
Scanning Microscopy
Serum retinal levels were studied in : (a) 95, 56 and 43 normal subjects belonging to lower, middle and upper socio-economic groups respectively, (b) 35 adult males suffering from night blindness, (c) 27 subjects with low retinal levels, (d) 8 retinal deficient subjects (e) 17 male infants suffering from overt retinal deficiency, (f) 43 radiologically confirmed stone patients and (g) age and sex matched controls (infants 20; adults 120). The subjects included in groups b to f were clinically and radiologically examined for stone disease. Some inhibitors and promoters of stone disease were estimated in urine in groups b to …
Strontium, A Tracer To Study The Transport Of Calcium In Mineralizing Tissues By Electron Probe Microanalysis, Ernst-Rudolf Krefting, Kai Frentzel, Jörg Teßarek, Hans-Jürgen Höhling
Strontium, A Tracer To Study The Transport Of Calcium In Mineralizing Tissues By Electron Probe Microanalysis, Ernst-Rudolf Krefting, Kai Frentzel, Jörg Teßarek, Hans-Jürgen Höhling
Scanning Microscopy
In growth plate cartilage the mineralization starts extracellularly in the lower hypertrophic zone. The mineral formed is the calcium phosphate apatite. Enough calcium and phosphate must be available at the mineralization front as well as in regions with proceeding mineralization. There must be a transport of Ca (and phosphate) to these sites.
Electron probe X-ray microanalysis is a well established method to analyze element concentrations in small volumes, but it cannot discriminate isotopes. Strontium is similar to Ca in its chemical and biological behaviour and is therefore a suitable tracer to investigate the transport of Ca.
Small amounts of Sr …
Review: Morphological Changes Associated With Endolymphatic Hydrops, K. C. Horner
Review: Morphological Changes Associated With Endolymphatic Hydrops, K. C. Horner
Scanning Microscopy
Endolymphatic hydrops of the inner ear is identified as a swelling of the endolymphatic spaces. This morphopathology in man can only be confirmed at postmortem examination although it is believed to underlie the auditory dysfunction and vestibular disturbances associated with Menière's disease. This is an illusive inner ear disorder characterized typically by the fluctuant hearing loss, tinnitus and episodes of vertigo. Menière's disease remains a major problem in otorhinolaryngology since the cause of the disease is not known and various treatments are recommended, often with unsatisfactory results. Experimentally induced endolymphatic hydrops in the animal model has been developed in order …
Long Term Mobidity And Mortality Of Adolescent Obesity: A Follow-Up Of Third Harvard Growth Study Participants Of 1922 To 1935, Aviva Must Ph.D., Paul F. Jacques Sc.D., Gerard E. Dallal Ph.D., Carl J. Bajema Ph.D., William H. Dietz M.D., Ph.D
Long Term Mobidity And Mortality Of Adolescent Obesity: A Follow-Up Of Third Harvard Growth Study Participants Of 1922 To 1935, Aviva Must Ph.D., Paul F. Jacques Sc.D., Gerard E. Dallal Ph.D., Carl J. Bajema Ph.D., William H. Dietz M.D., Ph.D
Peer Reviewed Publications
Background. Overweight in adults is associated with increased morbidity and mortality. In contrast, the long-term effect of overweight in adolescence on morbidity and mortality is not known.
Methods. We studied the relation between overweight and morbidity and mortality in 508 lean or overweight adolescents 13 to 18 years old who participated in the Harvard Growth Study of 1922 to 1935. Overweight adolescents were defined as those with a body-mass index that on two occasions was greater than the 75th percentile in subjects of the same age and sex in a large national survey. Lean adolescents were defined as those with …
Mercox®-Methylmethacrylic Acid Mixture Penetrates Into Cells. A Scanning And Transmission Electron Microscopic Study, S. Aharinejad, P. Böck
Mercox®-Methylmethacrylic Acid Mixture Penetrates Into Cells. A Scanning And Transmission Electron Microscopic Study, S. Aharinejad, P. Böck
Scanning Microscopy
During preparation of vascular casts using mixtures of Mercox® and methylmethacrylic acid for scanning electron microscopy, occasionally irregular structures were observed adhering to otherwise well prepared corrosion casts. These artifacts were further analyzed in sections of cast preparations. The bizarre-shaped structures varied in size and were often tightly connected to vascular casts; they withstood KOH maceration and cleaning with formic acid. The persistence of biological material, connective tissue fibers and cells or cellular fragments, became obvious in ultrathin sections. Transmission electron microscopy also showed inhomogeneity of the polymerized casting medium (Mercox®-methylmetbacrylate mixture; v/v: 4:1). An unidentified com-pound of this resin …