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Articles 19231 - 19260 of 20606
Full-Text Articles in Entire DC Network
Bovine Aorta Endothelial Cell Incubation With Interleukin 2: Morphological Changes Correlate With Enhanced Vascular Permeability, Corazon D. Bucana, Joann Trial, Audrey C. Papp, Kenneth K. Wu
Bovine Aorta Endothelial Cell Incubation With Interleukin 2: Morphological Changes Correlate With Enhanced Vascular Permeability, Corazon D. Bucana, Joann Trial, Audrey C. Papp, Kenneth K. Wu
Scanning Microscopy
Interleukin 2 induced alterations in the morphology of bovine aortic endothelial cells in vitro. The changes observed in confluent cultures of bovine aortic endothelial cells included retraction and elongation of eel ls leading to enlarged gaps between cells quantified by image analysis. Purified IL-2 (1 U/ml medium) increased the gaps between endothelial cells 3-4-fold compared with control cultures. The effect was transient, since the cells reverted to their original morphology 6-12 hours after the removal of lL-2. Correlative scanning electron microscopy (SEM) studies using fresh bovine aorta showed a dose-dependent alteration of the endothelial surface by IL-2 characterized by rounding …
Studies Of Intestinal Lymphoid Tissue. Xi – The Immunopathology Of Cell-Mediated Reactions In Gluten Sensitivity And Other Enteropathies, Michael N. Marsh
Studies Of Intestinal Lymphoid Tissue. Xi – The Immunopathology Of Cell-Mediated Reactions In Gluten Sensitivity And Other Enteropathies, Michael N. Marsh
Scanning Microscopy
Computerised image-analysis was used to quantitate small intestinal mucosae from celiac sprue and dermatitis herpetiformis patients, Gambian children with tropical-sprue-like malabsorption, first-degree celiac sprue relatives, and treated celiac sprue patients during challenge with a peptic-tryptic digest of gluten. A wide range of mucosal appearances was observed. Typically, 'flat' lesions (Type 2) revealed a reduced number of epithelial lymphocytes that were large and mitotically active. At the other extreme, mucosal architecture was relatively well preserved (Type 1) but surface epithelium contained an expanded population of small, non-mitotic lymphocytes, with or without crypt hyperplasia. Similar changes were observed in one-third of celiac …
Correlation Between Auditory Brainstem Recordings And Morphology As Seen Through The Scanning Electron Microscope, M. Hultcrantz
Correlation Between Auditory Brainstem Recordings And Morphology As Seen Through The Scanning Electron Microscope, M. Hultcrantz
Scanning Microscopy
Pregnant CBA/CBA mice were exposed to 0.5, 1 and 2 Grey (Gy), (1 Gy = 100 rad) in single doses with whole body gamma-irradiation on the 12th, 13th and 16th gestational days, respectively. The animals were tested at an age of one month for vestibular and cochlear function. Thereafter the inner ears were analyzed with scanning electron microscopy. A morphological analysis with cytocochleograms was performed.
Morphological changes in the vestibular part showed gross malformations in the cristae ampullares. Hair cells of type I seemed to be more severely changed than hair cells type II. The macula utriculi also showed malformations …
Patterns Of Sulfur Deposition In The Wood Of Pinus Echinatia Mill. From The Cumberland Plateau In Kentucky, Darrell Ray
Patterns Of Sulfur Deposition In The Wood Of Pinus Echinatia Mill. From The Cumberland Plateau In Kentucky, Darrell Ray
Masters Theses & Specialist Projects
Air pollution and acid precipitation have long had an influence on plant and animal life. In this study, the level of sulfur in the stem tissue of Pinus echinata Mill. was measured in trees from various sites along the western edge of the Cumberland Plateau to determine the presence and pattern of sulfur deposition in this species. Overall, a 40.28% increase in sulfur levels was observed from four sites along the plateau with levels increasing from 0.072 mgS/gdwt in the 1962-66 growth increment to 0.101 mg in the 1982-86 increment. According to a computer generated analysis of variance, the differences …
The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton
The Occurrence Of Fish Remains In Modern Lake Systems : A Test Of The Stratified-Lake Mode, Douglas R. Britton
Loma Linda University Electronic Theses, Dissertations & Projects
Theories regarding the taphonomy of fishes in lacustrine environments have traditionally relied on an anoxic water column to explain the excellent preservation. This concept has never been directly tested in modern lacustrine environments that are thought to be analogous to the lacustrine environments predicted by the Stratified-lake Model. This research tested that model by searching for fish remains in 38 collected bottom samples of six modern lacustrine analogues, including Fayetteville Green Lake, New York. The bottom sediments of a warm, holomictic, shallow, and saline lake (Salton Sea, California) were also examined. Although laminated sediments were found in all of the …
A Descriptive Catalog Of Dimming Cells In The Purple Shore Crab Hemigrapsus Nudus, Eugene Pak
A Descriptive Catalog Of Dimming Cells In The Purple Shore Crab Hemigrapsus Nudus, Eugene Pak
Loma Linda University Electronic Theses, Dissertations & Projects
A population of cells responsive to the decrease or dimming of light was identified in the Purple shore crab Hemigrapsus nudus. Extracellular pin electrode recordings from the optic nerve tract measured responses to decremental changes in relative light levels over the range 40 to 0.08 lux. The observed activity revealed that these dimming cells could respond over this entire range. A catalog detailing the response characteristics for each of the thirty dimming cells in the study was generated. The parameters measured the receptive field size; response to mechanoreceptive tactile stimuli; response to abrupt On or Off light level changes; …
Chemoreceptors Regulate Discharge Of Microbasic P-Mastigophores In The Sea Anemone, Aiptasia Pallida, Gail E. Muir Giebel
Chemoreceptors Regulate Discharge Of Microbasic P-Mastigophores In The Sea Anemone, Aiptasia Pallida, Gail E. Muir Giebel
Loma Linda University Electronic Theses, Dissertations & Projects
Recently, using cnida-mediated measurements of adhesive force, Thorington and Hessinger (1984, 1988a, b) identified two different chemoreceptors involved in triggering cnida discharge on the tentacles of the sea anemone, Aiptasia pallida. These two classes of receptors were shown to interact with glycine and N-acetylneuraminic acid (NANA). We now show that the discharge of the microbasic p-mastigophores, one of the three types of cnidae present on the tentacles of A. pallida, is under the controlling influence of these two classes of cnidocyte-associated chemoreceptors. We also demonstrate that the number of discharged microbasic p-mastigophores adhering to the test probes is proportional to …
Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation
Characterization Of The Aquatic Environment In Lake Mead Near The Proposed Spring Canyon Pumped-Storage Project, And Assessment Of Potential Aquatic Impacts, Charles R. Liston, Stephen J. Grabowski, Bureau Of Reclamation
Publications (WR)
A pumped storage system consists of an upper reservoir and lower reservoir separated by an elevation difference. During low demand energy periods such as nights and weekends water is pumped from the lower to the upper reservoir using available energy from conventional steam electric power plants. During high energy demand periods, such as mornings and afternoons of weekdays, upper reservoir water is allowed to drop back down through the same system of water conduits and turbines, generating electricity to conveniently meet abrupt electrical energy requirements. The same water turbines thus act both as pumps and as conventional hydroelectric turbines. Because …
Histology Of The Ovaries And Fat Bodies Of Chthonerpeton Indistinctum, Rafael O. De Sá, Nibia Berois
Histology Of The Ovaries And Fat Bodies Of Chthonerpeton Indistinctum, Rafael O. De Sá, Nibia Berois
Biology Faculty Publications
Histological analysis revealed three different stages in the development of ovarian follicles of Chthonerpeton indistinctum. These stages are identified by (1) location of the oocyte in the ovary wall, (2) oocyte morphology and staining characteristics, (3) development of the zona pellucida, and (4) organization of the follicular layer. Atretic follicles and corpora lutea also were found. Fat bodies are composed of well-developed adipose tissue.
Polarized Epithelial Cysts In Vitro: A Review Of Cell And Explant Culture Systems That Exhibit Epithelial Cyst Formation, J. A. Mcateer, G. S. Dougherty, K. D. Gardner Jr., A. P. Evan
Polarized Epithelial Cysts In Vitro: A Review Of Cell And Explant Culture Systems That Exhibit Epithelial Cyst Formation, J. A. Mcateer, G. S. Dougherty, K. D. Gardner Jr., A. P. Evan
Scanning Microscopy
The purpose of this paper is to review in vitro cell and explant culture systems that exhibit epithelial cyst formation and that are used as models of polarized epithelial function. We examine a number of culture systems derived from a variety of cell and organ types, briefly describe the methodology and conditions used to establish these cultures and discuss aspects of the experimental application of each system. We conclude that the characteristics of epithelial cyst-forming cultures are dependent upon the origin and identity of the cell population, as well as the multiple factors that define the culture environment. Culture systems …
The Role Of Scanning Electron Microscopy In Ophthalmic Science, P. Versura, M. C. Maltarello
The Role Of Scanning Electron Microscopy In Ophthalmic Science, P. Versura, M. C. Maltarello
Scanning Microscopy
The eyeglobe is one of the classical domains of Scanning Electron Microscopy (SEM) in biology as it exposes several inner and outer surfaces. Both corneal and conjunctival epithelia towards the tear film as well as the corneal endothelial cells facing the anterior chamber may be accurately evaluated. The architecture of the angle and particularly the morphology of the Schlemm's canal inner wall are clarified by SEM more than by TEM serial reconstruction. The surfaces of the iris and ciliary body, the zonula and the choroidal vessel arrangement are described in great detail. Three distinct types of membrane anchoring devices are …
Preparation Of Cytoskeletons Of Cells In Culture For High Resolution Scanning And Scanning Transmission Electron Microscopy, Paul B. Bell Jr., Margaretha Lindroth, Bengt-Arne Fredriksson
Preparation Of Cytoskeletons Of Cells In Culture For High Resolution Scanning And Scanning Transmission Electron Microscopy, Paul B. Bell Jr., Margaretha Lindroth, Bengt-Arne Fredriksson
Scanning Microscopy
In this tutorial we describe our methods for preparing detergent-extracted cytoskeletons for observation by high resolution scanning (SEM) and scanning transmission (STEM) electron microscopy. We both discuss the theoretical background and provide practical procedures for each of the following steps: cell culture on Formvar-coated gold grids; prefixation with aldehydes or protein crosslinking reagents (homobifunctional N-hydroxy-succinimide esters); extraction with Triton X-100 or Brij 58 detergent in microtubule stabilizing buffer; postfixation in formaldehyde and glutaraldehyde; dehydration; critical point and freeze drying; sputter coating with 1-2 nm of platinum or tungsten; and examination by SEM and both normal and inverted contrast STEM. These …
Preparation Of Cultured And Isolated Cells For X-Ray Microanalysis, K. Zierold, D. Schäfer
Preparation Of Cultured And Isolated Cells For X-Ray Microanalysis, K. Zierold, D. Schäfer
Scanning Microscopy
Various electron microscopical preparation techniques are compared with regard to the preservation of the intracellular element distribution as determined by X-ray microanalysis in scanning and scanning transmission electron microscopy. By use of chemical agents for fixation and dehydration ions are redistributed and washed out. This is also true for freeze-substitution. Whole cells are prepared by cryofixation followed by freeze-drying. Interference of intracellular measurements by extracellular elements can be avoided by appropriate washing the cells before cryofixation. The washing medium has to be carefully selected in order to avoid distortions of the original intracellular element content. These problems are circumvented by …
The Effect Of Iron And Lead Inhibition, Beth Brownell
The Effect Of Iron And Lead Inhibition, Beth Brownell
Whittier Scholars Program
This project is an experiment to test the hypothesis that the amount of iron present in the body affects the biosynthetic pathway of heme in experimental animals. This study was done by monitoring the protoporphyrin IX blood levels in four mice groups: no lead in drinking water with normal iron pellet diet, no lead in drinking water with no iron pellet diet, 1mM lead in drinking water with normal iron pellet diet, and 1mM lead in drinking water with no iron pellet diet. Fluorescence spectra of diluted whole blood from lead-exposed mice with different iron levels were found to be …
Enamel Of Yalkaparidon Coheni: Representative Of A Distinctive Order Of Tertiary Zalambdodont Marsupials, K. S. Lester, M. Archer, C. F. Gilkeson, T. Rich
Enamel Of Yalkaparidon Coheni: Representative Of A Distinctive Order Of Tertiary Zalambdodont Marsupials, K. S. Lester, M. Archer, C. F. Gilkeson, T. Rich
Scanning Microscopy
The enamel of an incisor and a premolar of Yalkaparidon coheni was examined by scanning electron microscopy in fractured and in sectioned, polished surfaces. The enamel of both teeth demonstrated: complete, ovoid and horse-shoe shaped prisms in a Pattern 2 arrangement; a simple parallel prism course; and, enamel tubules in abundance in the premolar but restricted to the innermost enamel in the incisor. Overall, the enamel ultrastructure supports the marsupial affiliation proposed for Yalkaparidon coheni but does not unambiguously ally it with any other order of marsupials.
The observation of a significant ultrastructural difference between the anterior and posterior teeth …
Sensory Stimuli Involved In Eliciting Agonistic Behavior In The Northern Fence Lizard, Sceloporus Undulatus Hyacinthinus, Laura Taylor
Sensory Stimuli Involved In Eliciting Agonistic Behavior In The Northern Fence Lizard, Sceloporus Undulatus Hyacinthinus, Laura Taylor
Masters Theses & Specialist Projects
Comparisons among sequence analyses of actions in response to various treatments of visual and olfactory cues were carried out in the lizard, Sceloporus undulatus hyacinthinus, to determine the relative roles of these cues in eliciting agonistic behavior. Visual cues were tested using mirrors, models and clear partitions between cages. Chemical cues were tested using the secretion from the cloaca of males. A combination of visual and olfactory cues was tested by streaking a mirror with the substance from the cloaca of a male. The responses to these treatment conditions were videotaped, and the transition frequencies between the most frequently …
Intracellular Water Distribution And Aging As Examined By X-Ray Microanalysis, Thomas Von Zglinicki
Intracellular Water Distribution And Aging As Examined By X-Ray Microanalysis, Thomas Von Zglinicki
Scanning Microscopy
The results reviewed here demonstrate that 1. the distribution of dry mass as observed in frozen-dried cryosections might be used as an unbiased measure of intracellular dry mass resp. water distributions in the tissue in vivo and 2. the well-known loss of water from cells during aging is solely due to a water loss from mitochondria without changes in the water content of all other components of the cell in the case of rat liver and heart muscle.
The reason for the water loss might be increased counter ion binding by membrane-bound enzymes due to decreased fluidity of the inner …
Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman
Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The D-variant of encephalomyocarditis (EMC-D) virus was given to SJL/J mice by the artificial, intraperitoneal (ip) route of infection, or by the natural routes of infection per os (po) or intranasal (i.n.), in comparable concentrations. The po route of infection was found to be ineffective. Mice given virus by either the ip or i.n. routes of infection became diabetic. Mice were more resistant to the infectious and diabetogenic properties of the virus when given by the i.n. than when given by the ip route. Glycosuria in mice given virus i.n. usually lagged one day behind that in mice given virus …
Characterization Of Esterases And Glutathione S-Transferases In A Solitary Bee, Megachile Rotundata (Fab.): Variability, Developmental Multiplicity, Substrate Specificity, And Inhibition, Donald R. Frohlich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The esterases and glutathione S-transferases of a solitary bee, Megachile rotundata (Fab.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were characterized by electrophoresis, substrate specificity, and inhibition studies. Comparisons were made between ages, sexes, and life stages for several classes of substrates and their isomers: aromatic, aliphatic, and thio-esters. Two esterases were found to be allozymes and variable between individuals and sexes. Adults typically possess an esterase that hydrolyzes fluorescent substrates, an organophosphate insensitive esterase, and a series of type 'B' esterases that are very sensitive to organophosphate inhibition. Electrophoretic patterns are different between adults and immatures and are probably …
Proton Microprobe And Particle Induced X-Ray Emission (Pixe) Analysis For Studies Of Pathological Brain Tissue, K. G. Malmqvist, A. Brun, K. Inamura, E. Martins, L. G. Salford, B. K. Siesjö, U. A. S. Tapper, K. Themner
Proton Microprobe And Particle Induced X-Ray Emission (Pixe) Analysis For Studies Of Pathological Brain Tissue, K. G. Malmqvist, A. Brun, K. Inamura, E. Martins, L. G. Salford, B. K. Siesjö, U. A. S. Tapper, K. Themner
Scanning Microscopy
Particle Indiced X-ray Emission and proton microprobe analyses have been applied for the investigation of regional elemental distributions in connection with various pathological states in the brain. Malignant brain tumours and adjacent histologically intact tissue removed during surgery were analysed with PIXE. Systematic elemental variations, e.g., for calcium and selenium, were observed in the tumour front. The proton microprobe was applied to study the Ca and K concentrations in various cell strata in hippocampus following transient ischaemia in rat brain. Significant increases in the Ca level occurred in selectively vulnerable cells within 48 h after the ischaemia.
Effects Of Ethanol And Caffeine Administered Maternally On Neonatal Adrenocortical Function, Rhonda L. Mullins Rohlfing
Effects Of Ethanol And Caffeine Administered Maternally On Neonatal Adrenocortical Function, Rhonda L. Mullins Rohlfing
Biological Sciences Theses & Dissertations
Two investigations were conducted to determine the effects of maternally administered ethanol and caffeine on neonatal adrenocortical function. In the ethanol study, pregnant female rats were fed a liquid diet in which 35% of the sucrose calories were removed and replaced with ethanol. Dams in the caffeine study were injected with 25 mg/kg/day caffeine in saline solution. Within 24 hours of parturition, neonatal rats in both studies were sacrificed. The adrenal glands were incubated in vitro for one hour and media were analyzed for corticosterone content. Significant adrenal weight differences were found in both studies. The ethanol group pups were …
Scanning Electron Microscopy Of The Spermatheca Of Plethodon Larselli (Amphibia: Plethodontidae): Changes In The Surface Morphology Of The Spermathecal Tubule Prior To Ovulation, Christine M. Davitt, John H. Larsen Jr.
Scanning Electron Microscopy Of The Spermatheca Of Plethodon Larselli (Amphibia: Plethodontidae): Changes In The Surface Morphology Of The Spermathecal Tubule Prior To Ovulation, Christine M. Davitt, John H. Larsen Jr.
Scanning Microscopy
Spermathecae from eight mature female Larch Mountain salamanders (Plethodon larselli) were used to study cellular changes accompanying the administration of ovulation-inducing pregnant mare serum gonadotropin (PMSG). Animals injected daily with 25 IU of PMSG were sacrificed on day 2 or day 4. Ultrastructural alterations of the spermathecal tubules include an increase in the synthesis and release of product into the lumen and hypertrophy of two epithelial cell types by day 4. One cell type exhibits apocrine blebs and is covered with microvilli; the other contains large spherical vesicles and has only a few, short microvilli on its surface. These changes …
Sem Of Canine Chromosomes: Normal Structure And The Effects Of Whole-Body Irradiation, G. K. Niiro, T. M. Seed
Sem Of Canine Chromosomes: Normal Structure And The Effects Of Whole-Body Irradiation, G. K. Niiro, T. M. Seed
Scanning Microscopy
Canine chromosomes are not only numerous (38 autosomal pairs), but they are small (compared to human chromosomes) and morphologically similar as well. Analysis of the canine karyotype by light microscopy (LM) of banded chromosomes is, thus, difficult, and the literature on the canine karyotype is scanty. In this study, we describe examination of chromosomes from normal and chronically irradiated dogs with the scanning elect ran microscope (SEM). Metaphase chromosomes from bone marrow aspirates were Giemsa-banded with either 0.025% trypsin alone or 0.1% trypsin preceded by 10% H2O2 and prepared for SEM. Examination of chromosomes from normal dogs revealed cylindrical chromosome …
Enamel Structure In Primates: A Review Of Scanning Electron Microscope Studies, L. B. Martin, A. Boyde, F. E. Grine
Enamel Structure In Primates: A Review Of Scanning Electron Microscope Studies, L. B. Martin, A. Boyde, F. E. Grine
Scanning Microscopy
Comparative studies of dental enamel microstructure have involved three main areas of enquiry, with structural features having been investigated in relation to developmental mechanisms, function and/or phylogeny. The phylogenetic, or taxonomic aspect has been emphasized in the majority of studies involving the Order Primates, where efforts have focused upon attempts to recognise structural differences among various hierarchical groups.
Studies of primate enamel microstructure by SEM are reviewed here, with emphasis on what has been learned concerning the most suitable preparative techniques that can be employed, and with particular emphasis to the relevance of enamel microstructure in taxonomic analyses of living …
Microscopic Effects Of Predator Digestion On The Surfaces Of Bones And Teeth, John M. Rensberger, Hartmut B. Krentz
Microscopic Effects Of Predator Digestion On The Surfaces Of Bones And Teeth, John M. Rensberger, Hartmut B. Krentz
Scanning Microscopy
Concentrations of small fossil mammals are frequently encountered in Cenozoic deposits, but the causes for such accumulations have seldom been determined. In many cases the tooth, jaw, and limb fragments appear to be well-preserved under light microscopy, and it is difficult to differentiate damage due to predator digestion from breakage and abrasion due to physical agents. In order to find more specific evidence of predator digestion, we used a scanning electron microscope (SEM) to examine the surface microstructure of bones and teeth consumed by Bubo virginianus (great horned owl) and Canis latrans (coyote), which prey upon similar species. Effects …
Febrile Response And Activity In The Crayfish, Pacifasticus Leniusculus Trowbridgii, Kenneth A. Fletcher
Febrile Response And Activity In The Crayfish, Pacifasticus Leniusculus Trowbridgii, Kenneth A. Fletcher
Dissertations and Theses
Poikilothermic and endothermic animals demonstrate febrile response to infection with bacteria or to injection with endogenous pyrogen extract of Prostaglandin E1. Febrile response is measured in endotherms as a relative change in metabolically achieved body temperature and in poikilotherms as an increase in selected temperatures relative to previously established preferred temperatures. Final preferendum change with environmental factors or associated physiological states.
Crayfish Pacifasticus leniusculus trowbridgii were injected with 0.2 ml suspension of alcohol-killed gram-negative Aeromonas hydrophila bacteria in 0.9% saline. Injections were into the coxopodite of the cheliped. The crayfish were monitored in an aquatic thermal gradient by …
Leafcutting And Diet Selection: Relative Influence Of Leaf Chemistry And Physical Features, Jerome J. Howard
Leafcutting And Diet Selection: Relative Influence Of Leaf Chemistry And Physical Features, Jerome J. Howard
Biological Sciences Faculty Publications
The effects of leaf toughness, trichome characteristics, nutrient and water availability, and secondary chemistry on diet selection by the leafcutting ant Atta cephalotes were determined using individuals of 49 woody plant species from a tropical deciduous forest in Costa Rica. The palatability of plants was measured by presenting whole leaves to leafcutting ant foragers on trails and counting the number of pieces cut from leaves. The effectiveness of physical barriers to leaf cutting was evaluated by measuring the speed with which ants were able to cut leaves of varying toughness, trichome densities, and trichome lengths. Plant secondary chemistry was highly …
Genetic Distance And Hybridization Of Black Ducks And Mallards: A Morph Of A Different Color?, G. R. Hepp, James M. Novak, K. T. Scribner, P. W. Stangel
Genetic Distance And Hybridization Of Black Ducks And Mallards: A Morph Of A Different Color?, G. R. Hepp, James M. Novak, K. T. Scribner, P. W. Stangel
Faculty Research & Creative Activity
No abstract provided.
A Late Miocene Marlin, Makaira Sp. (Perciformes, Osteichthyes) From San Diego County, California, U.S.A., Harry L. Fierstine, Bruce J. Welton
A Late Miocene Marlin, Makaira Sp. (Perciformes, Osteichthyes) From San Diego County, California, U.S.A., Harry L. Fierstine, Bruce J. Welton
Biological Sciences
Fossil bones collected in the latest Miocene (= either late Clarendonian or early Hemphillian North American Land IvIammal Age), San Mateo Formation, near Oceanside, San Diego County, California, C. S.A., belong to a single specimen of the genus Makaira, species undetermined, and is part of the San Luis Rey River Local Fauna. For the genus, this represents the fifth discovery in fossil deposits bordering or within the Pacific Ocean region, and the third discovery in southern California, The specimen is within the known geochronological distribution of the genus (Late Miocene to Recent), provides further evidence that the coastal palaeoclimate of …
A New Method Of Calculating The Wing Area Of Bats, B.R. Blood, Donald A. Mcfarlane
A New Method Of Calculating The Wing Area Of Bats, B.R. Blood, Donald A. Mcfarlane
WM Keck Science Faculty Papers
Wing area is a parameter important to any study of chiropteran flight behaviour (Struthsaker 1961 ; Findley et al. 1972 ; Lawlor 1973), because it is a necessary component for the calculation of aspect ratio and wing loading. Bats possessing high aspect ratio wings usually display swift and steady flight, often at high altitudes. Bats that possess low aspect ratio wings usually display slower, more manouverable flight and often fly at lower altitudes (Findley 1972 ; Findley et al. 1972 ; Mortensen 1977 ; Vaughan 1970). However, despite the importance of wing area, no-one has published a simple, yet accurate, …