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Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - Law Enforcement Considerations (Volume 4), Neil Mclaughlan Oct 1994

Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - Law Enforcement Considerations (Volume 4), Neil Mclaughlan

Fisheries Management Papers

This report has been prepared for the consideration of the RLIAC Sub Committee in consultation with members of the Sub Committee working group on law enforcement and with senior staff of the Operations Division of the Fisheries Department. It is focussed exclusively on law enforcement issues associated with the management options for the West Australian west coast rock lobster fishery which were under consideration by the Sub Committee at the time of report preparation and should be read in conjunction with Fisheries Management Paper No. 67 entitled "Evaluation of management options" which covers the broader industry management issues. This report …


Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - A Market-Based Economic Assessment For The Western Rock Lobster Industry (May 1994) (Volume 3), Marec Pty Ltd Oct 1994

Long Term Management Strategies For The Western Rock Lobster Fishery (4 Volumes) - A Market-Based Economic Assessment For The Western Rock Lobster Industry (May 1994) (Volume 3), Marec Pty Ltd

Fisheries Management Papers

In October 1992 a special Sub-Committee of the Rock Lobster Industry Advisory Committee was set up to consider and evaluate future management strategies for the rock lobster fishery. Pursuant to this the Director of Fisheries commissioned a marketing study that is the basis of this report. This study was commenced in early October 1993 and completed in May 1994. This study looked at the market implications of fishery's management strategies. In particular it assesses how the existing management structure limits the potential for the lobster industry to maximise the financial return, and in doing so provides an insight into the …


Long Term Management Strategies For The Western Rock Lobster Industry (4 Volumes) - Economic Efficiency Of Alternative Input And Output Based Management Systems In The Western Rock Lobster Fishery (Volume 2), Bob Lindner Oct 1994

Long Term Management Strategies For The Western Rock Lobster Industry (4 Volumes) - Economic Efficiency Of Alternative Input And Output Based Management Systems In The Western Rock Lobster Fishery (Volume 2), Bob Lindner

Fisheries Management Papers

Since 1965, the Western Rock Lobster Fishery has been managed by what is essentially a license limitation scheme invoiving restricted entry for boats, and strict controls on the aggregate number of pots which can be used by the commercial fishing sector. By most measures, management of this fishery has been highly successful. Biological over-exploitation of the fish stock has been prevented, at least until recently. Notwithstanding these achievements, there is widespread concern that the future profitability, and even the viability of the industry is under threat unless the current management practices are reformed. Because of the complexity and intrinsic uncertainty …


Long Term Management Strategies For The Western Rock Lobster (4 Volumes) - Evaluation Of Management Options (Volume 1), B. K. Bowen, Rock Lobster Industry Advisory Committee Oct 1994

Long Term Management Strategies For The Western Rock Lobster (4 Volumes) - Evaluation Of Management Options (Volume 1), B. K. Bowen, Rock Lobster Industry Advisory Committee

Fisheries Management Papers

This report has been written following approval by the Minister for Fisheries of a recommendation by the Rock LObster Industry Advisory Committee that a major evaluation of future management options for the western rock lobster fishery be undertaken. The report provides background information on the management strategies and principles of the fishery, its stock status, the use of input and output controls and the size of the fishing fleet. The report concludes with an examination of the effect of maintaining effort (input) controls and moving to a system of variable effort (TAE/ITEs) or moving to direct (output) controls on the …


Instructions For Building Two Live Traps For Small Mammals, Robert K. Rose Oct 1994

Instructions For Building Two Live Traps For Small Mammals, Robert K. Rose

Biological Sciences Faculty Publications

The two live traps described herein, tested in the field over a period of 10 years, are sturdy, long-lasting, and relatively inexpensive to build with readily available materials and simple tools.


Force-Velocity And Power Characteristics Of Rat Soleus Muscle Fibers After Hindlimb Suspension, Kerry S. Mcdonald, C. A. Blaser, Robert H. Fitts Oct 1994

Force-Velocity And Power Characteristics Of Rat Soleus Muscle Fibers After Hindlimb Suspension, Kerry S. Mcdonald, C. A. Blaser, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The effects of 1, 2, and 3 wk of hindlimb suspension (HS) on force-velocity and power characteristics of single rat soleus fibers were determined. After 1, 2, or 3 wk of HS, small fiber bundles were isolated, placed in skinning solution, and stored at -20 degrees C until studied. Single fibers were isolated and placed between a motor arm and force transducer, functional properties were studied, and fiber protein content was subsequently analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Additional fibers were isolated from soleus of control and after 1 and 3 wk of HS, and fiber type distribution …


Lag-2 May Encode A Signaling Ligand For The Glp-1 And Lin-12 Receptors Of C-Elegans, Samuel T. Henderson, Dali Gao, Eric J. Lambie, Judith Kimble Oct 1994

Lag-2 May Encode A Signaling Ligand For The Glp-1 And Lin-12 Receptors Of C-Elegans, Samuel T. Henderson, Dali Gao, Eric J. Lambie, Judith Kimble

Dartmouth Scholarship

The C. elegans lag-2 gene is required for several cell-cell interactions that rely on the receptors GLP-1 and LIN-12. In this paper, we report that lag-2 encodes a putative membrane protein with sequence similarity to Drosophila Delta, a proposed ligand for the Notch receptor. Furthermore, we show that the lag-2 promoter drives expression of a reporter protein in the signaling distal tip cell (DTC) of the DTC/germline interaction. By in situ hybridization, we have found that endogenous lag-2 mRNA is present in the DTC but not the germ line. One fusion protein, called LAG-2::beta-gal(intra), rescues a lag-2 null mutant and …


The Pha-4 Gene Is Required To Generate The Pharyngeal Primordium Of Caenorhabditis-Elegans, Susan E. Mango, Eric J. Lambie, Judith Kimble Oct 1994

The Pha-4 Gene Is Required To Generate The Pharyngeal Primordium Of Caenorhabditis-Elegans, Susan E. Mango, Eric J. Lambie, Judith Kimble

Dartmouth Scholarship

In the 4-cell Caenorhabditis elegans embryo, two blastomeres are destined to generate pharyngeal cells, each by a distinct developmental strategy: one pathway is inductive, while the other is autonomous. Here, we identify the pha-4 locus. In animals lacking pha-4 activity, an early step in pharyngeal organogenesis is blocked: no pharyngeal primordium is formed and differentiated pharyngeal cells are absent. Most other tissues are generated normally in pha-4 mutants, including cells related to pharyngeal cells by cell lineage and position. Thus, pha-4 activity is required to form the pharyngeal primordium. We propose that pha-4 marks a convergence of the inductive and …


Urinary Citrate, Bone Resorption And Intestinal Alkali Absorption In Stone Formers With Fasting Hypercalciuria, Piergiorgio Messa, Giuseppe Mioni, L. Paganin, A. Cruciatti, P. Lo Greco, D. Turrin Sep 1994

Urinary Citrate, Bone Resorption And Intestinal Alkali Absorption In Stone Formers With Fasting Hypercalciuria, Piergiorgio Messa, Giuseppe Mioni, L. Paganin, A. Cruciatti, P. Lo Greco, D. Turrin

Scanning Microscopy

Reduced citrate in urine and increased fasting excretion of calcium are abnormalities frequently reported in stone forming (SF) patients. Increased dietary acid (or reduced alkali) introduction or absorption may be a potential cause of both these pathological findings. To test this hypothesis, we studied 64 SF patients {32 with fasting hypercalciuria (FH) and 32 without FH (NFH)}. After a basal evaluation for nephrolithiasis, while on a 500 mg calcium diet, they were evaluated for: (1) daily intestinal alkali absorption (IAA), by urinary electrolyte excretion; (2) basal concentrations of PTH, calcitonin (CT) and 1,25(OH)2-VitD; (3) oral calcium load for evaluation of …


Diluted And Undiluted Mercox Severely Destroy Unfixed Endothelial Cells. A Light And Electron Microscopic Study Using Cultured Endothelial Cells And Tadpole Tail Fin Vessels, J. Gassner, A. Lametschwandtner, T. Weiger, H. C. Bauer Sep 1994

Diluted And Undiluted Mercox Severely Destroy Unfixed Endothelial Cells. A Light And Electron Microscopic Study Using Cultured Endothelial Cells And Tadpole Tail Fin Vessels, J. Gassner, A. Lametschwandtner, T. Weiger, H. C. Bauer

Scanning Microscopy

Mercox is a methylmethacrylate-based resin which is widely used for vascular corrosion casting with subsequent scanning electron microscopic analysis. In the present study the effect of undiluted and diluted Mercox (4+1; volume + volume; Mercox: monomeric methylmethacrylate (MMA); 0.02 g catalyst MA/ml Mercox) and methylmethacrylate with and without catalyst MA (0.625 g/10 ml MMA) on fixed and unfixed endothelial cells was studied. Light microscopy (LM) of cultured capillary endothelial cells (ECs), which were replicated with diluted or undiluted Mercox shows degranulation and membrane perturbation of ECs, while no morphological changes occur in glutaraldehyde-prefixed ECs. Scanning electron microscopy (SEM) of replicas …


Future Of Management Of Recreational Gill, Haul, And Cast Netting In Western Australia And Summary Of Submissions To The Netting Review, F. B. Prokop, L. M. Adams Sep 1994

Future Of Management Of Recreational Gill, Haul, And Cast Netting In Western Australia And Summary Of Submissions To The Netting Review, F. B. Prokop, L. M. Adams

Fisheries Management Papers

The results of a major review into recreational gill and haul netting in Western Australia were announced by the Minister for Fisheries, Hon. Monty House MLA on 24 December 1993. This document presents the findings of the recreational netting review and the process which resulted in the announced changed to management practices.


Benthic-Pelagic Links: Responses Of Benthos To Water-Column Nutrient Enrichment, S. C. Blumenshine, Yvonne Vadeboncoeur, D. M. Lodge, K. L. Cottingham, S. E. Knight Sep 1994

Benthic-Pelagic Links: Responses Of Benthos To Water-Column Nutrient Enrichment, S. C. Blumenshine, Yvonne Vadeboncoeur, D. M. Lodge, K. L. Cottingham, S. E. Knight

Biological Sciences Faculty Publications

Although the responses of pelagic algae and invertebrates to gradients of nutrient enrichment are well known, less is known about the responses of benthos to such gradients or how benthic and pelagic responses may interact. We performed a 9-wk experiment in 2000-L mesocosms in the field to test for the effect of water-column nutrient enrichment on phytoplankton, algae on sediments (epipelon) and hard surfaces (plastic strips), as well as pelagic and benthic primary consumers. The experimental design consisted of 4 nutrient enrichment rates (0, 0.5, 1.0 and 2.0 μg P L-1 d-1, together with N to yield …


Etiology Of Experimental Calcium Oxalate Monohydrate Nephrolithiasis In Rats, W. C. De Bruijn, E. R. Boevé, P. R. W. A. Van Run, P. P. M. C. Van Miert, J. C. Romijn, C. F. Verkoelen, L. C. Cao, F. H. Schröder Aug 1994

Etiology Of Experimental Calcium Oxalate Monohydrate Nephrolithiasis In Rats, W. C. De Bruijn, E. R. Boevé, P. R. W. A. Van Run, P. P. M. C. Van Miert, J. C. Romijn, C. F. Verkoelen, L. C. Cao, F. H. Schröder

Scanning Microscopy

In a rat-model system, tubular crystal retention as a possible mechanism for the etiology of nephrolithiasis in man, was studied by conventional transmission electron microscopy. The animals were supplied for nine days with a crystal-inducing diet, with ethylene glycol plus NH4Cl in their drinking-water. After this induction period, a two day regime with fresh drinking-water was included, to allow crystals to be removed by spontaneous crystalluria. After aldehyde fixation of the rat kidneys, large crystals were seen inside the tubular lumen. The crystals were attached to cell surfaces and covered by neighboring epithelial cells. Some crystals were overgrown …


Methodological Aspects Of Spontaneous Crystalluria Studies In Calcium Stone Formers, C. A. Bader, A. Chevalier, C. Hennequin, P. Jungers, M. Daudon, O. Beaugendre, M. P. Hoarau Aug 1994

Methodological Aspects Of Spontaneous Crystalluria Studies In Calcium Stone Formers, C. A. Bader, A. Chevalier, C. Hennequin, P. Jungers, M. Daudon, O. Beaugendre, M. P. Hoarau

Scanning Microscopy

Despite nearly a half-century of study, the clinical value of spontaneous crystalluria (Cx) examinations in calcium stone formers (CaSF) is still uncertain. The analytical complexity of urine particle study is largely responsible for this situation. As a result, there is no consensus regarding technical methods in Cx with several techniques for urine sampling and three different instruments currently used for particle study, namely, particle counting (PC), light microscopy (LM) and petrographic microscopy (PM). In this work, we first examined urine sampling and instrument methods regarding their appropriateness for Cx studies. Then we performed a comparative analysis of Cx studies in …


Arrangement Of Elastic Fibres In The Integument Of Domesticated Mammals, W. Meyer, K. Neurand, R. Schwarz, T. Bartels, H. Althoff Aug 1994

Arrangement Of Elastic Fibres In The Integument Of Domesticated Mammals, W. Meyer, K. Neurand, R. Schwarz, T. Bartels, H. Althoff

Scanning Microscopy

The hairy skin of important domesticated mammals (12 species) was studied with scanning electron microscopy, transmission electron microscopy, laser scanning microscopy, and several light microscopical methods, to obtain more information about three-dimensional elastic fibre arrangement. It was obvious that there is a basic construction scheme of the elastic fibre meshwork as present in the upper and mid-dermis, with special regard to the size, number, and grouping of hair follicles. In the densely-haired species, in particular, a typical elastic mat with horizontal fibres is formed. In many of the sparsely-haired animals, the upper and mid-dermis show a sponge-like elastic system. In …


General Pattern And Morphological Specializations Of The Avian Cochlea, Franz Peter Fischer Aug 1994

General Pattern And Morphological Specializations Of The Avian Cochlea, Franz Peter Fischer

Scanning Microscopy

In different bird species, there is a common pattern in the hair-cell morphology and innervation of the basilar papilla; the absolute values, however, are species-specific. In the barn-owl papilla, an extreme being case, the basal high-frequency part of the papilla is greatly expanded. In this behaviorally most important frequency range of the barn owl, the number of afferent nerve terminals to neural hair cells is extensively increased. Instead of about 2 afferent terminals as in other species, up to 20 afferents are present. In the bird species studied (chicken, starling, emu, barn owl), the area of the afferent nerve terminals …


Ultrastructural Patterns Of Cell Damage And Death Following Gamma Radiation Exposure Of Murine Erythroleukemia Cells, R. Di Pietro, E. Falcieri, L. Centurione, M. A. Centurione, G. Mazzotti, R. Rana Aug 1994

Ultrastructural Patterns Of Cell Damage And Death Following Gamma Radiation Exposure Of Murine Erythroleukemia Cells, R. Di Pietro, E. Falcieri, L. Centurione, M. A. Centurione, G. Mazzotti, R. Rana

Scanning Microscopy

Radiation causes damage to cell surface membranes, cytoplasmic organelles, and the nuclear process of DNA synthesis and repair, and this eventually results in different modes of cell death. In this study we examined murine erythroleukemia (MEL) cells, exposed to 15 and 60 Gy of 10 MeV photonic energy, and left in culture for up to 96 hours. Electron microscopical analysis was performed on conventionally embedded samples and freeze-fracture replicas, in order to detect ultrastructural patterns of cell damage and death. Of interest was the observation of chromatin condensates, nuclear membrane associations and nuclear pore redistribution during early apoptosis. Pronounced rearrangements …


Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler Aug 1994

Disparate Rates Of Molecular Evolution In Cospeciating Hosts And Parasites, M. S. Hafner, P. D. Sudman, F. X. Villablanca, T. A. Spradling, J. W. Demastes, S. A. Nadler

Biological Sciences

DNA sequences for the gene encoding mitochondrial cytochrome oxidase I in a group of rodents (pocket gophers) and their ectoparasites (chewing lice) provide evidence for cospeciation and reveal different rates of molecular evolution in the hosts and their parasites. The overall rate of nucleotide substitution (both silent and replacement changes) is approximately three times higher in lice, and the rate of synonymous substitution (based on analysis of fourfold degenerate sites) is approximately an order of magnitude greater in lice. The difference in synonymous substitution rate between lice and gophers correlates with a difference of similar magnitude in generation times.


Analysis Of The Distribution And Molecular Heterogeneity Of The Ospd Gene Among The Lyme Disease Spirochetes: Evidence For Lateral Gene Exchange, Richard T. Marconi, D. Scott Samuels, Robert K. Landry, Claude F. Garon Aug 1994

Analysis Of The Distribution And Molecular Heterogeneity Of The Ospd Gene Among The Lyme Disease Spirochetes: Evidence For Lateral Gene Exchange, Richard T. Marconi, D. Scott Samuels, Robert K. Landry, Claude F. Garon

Biological Sciences Faculty Publications

Analysis of the ospD gene has revealed that this gene is not universal among Lyme disease spirochete isolates. The gene was found to be carried by 90, 50, and 24% of the Borrelia garinii, B. afzelii, and B. burgdorferi isolates tested. Size variability in the ospD-encoding plasmid was also observed. Sequence analysis has demonstrated the presence of various numbers of a 17-bp repeated sequence in the upstream control (promoter) region of the gene. In addition, a region within the coding sequence where various insertions, deletions, and direct repeats occur was identified. ospD gene sequences from 31 different isolates were determined …


Glycol Methacrylate Embedding And Microwave Staining For Light Microscopy Of The Mouse Cochlea, Bharti Katbamna, Atha Ralston Aug 1994

Glycol Methacrylate Embedding And Microwave Staining For Light Microscopy Of The Mouse Cochlea, Bharti Katbamna, Atha Ralston

Scanning Microscopy

This study examined the utility of a methacrylate-based embedding medium and microwave staining for light microscopic quantification of hair cells and spiral ganglion cells in the mouse cochlea. The most important phase of the preparation process involved slowing down the polymerization process. The tissue molecules so locked within the plastic matrix produced excellent preservation of the organ of Corti and adjacent structures including the spiral ganglion, as well as tissue ionic charges. Excitable by microwaves, these ionic charges accelerated the movement of the basic dye (hematoxylin) into the tissue, reducing the time for this segment of the staining process from …


The Toxicity Of Cadmium To The Aquatic Amphibian, Xenopus Laevis, Sharon S. Millirons Aug 1994

The Toxicity Of Cadmium To The Aquatic Amphibian, Xenopus Laevis, Sharon S. Millirons

Master's Theses

Cadmium toxicity is poorly understood but is a potentially serious environmental pollutant. This study was initiated to determine the effect of significant concentrations of cadmium on a readily available aquatic laboratory organism.

The lethal concentration (LC50) for 50 percent of I week old Xenopus laevis tadpoles was determined to be 0.1 ppm CdCI 2. For 5 week old animals, the average LC50 was determined to be 0.98 ppm. Thus, cadmium poses greater toxic threats to the early developmental stages. Moreover, these concentrations of cadmium exceed those commonly found in the nation's water supply. Histological examination suggested that the main site …


Plumage Variation, Plasma Steroids And Social Dominance In Male House Finches, James R. Belthoff, Alfred M. Dufty Jr., Sidney A. Gauthreaux Jr. Aug 1994

Plumage Variation, Plasma Steroids And Social Dominance In Male House Finches, James R. Belthoff, Alfred M. Dufty Jr., Sidney A. Gauthreaux Jr.

Biology Faculty Publications and Presentations

In male House Finches (Carpodacusm exicanus), the extent and color of plumage varies depending on access to carotenoid pigments. "Colorful" males exhibit extensive red pigmentation, while less colorful (i.e., "drab") males exhibit carotenoid pigmentation over a smaller percentage of their plumage, pigmentation of a color besides red (e.g., yellow, gold, orange, or pink), or both. One explanation for maintenance of plumage variation is that it reliably reflects social status, allowing males to correctly assess their status in relation to others and avoid or minimize costly fights. Social relationships may also be related to endogenous factors, such as circulating levels of …


The Effect Of Insulin Mimetics On Enzymes Of Fatty Acid Biosynthesis, Eric A. Berg Aug 1994

The Effect Of Insulin Mimetics On Enzymes Of Fatty Acid Biosynthesis, Eric A. Berg

Masters Theses

Fatty acid biosynthesis, an insulin regulated pathway, is the process of producing fatty acid chains from 2 and 3 carbon units. Two enzymes in this pathway that insulin affects are glucose-6-phosphate dehydrogenase (G6PDH) and fatty acid synthase (FAS). Sodium vanadate and sodium selenate have demonstrated insulin-like effects in several tissue and cell types. These mimetic effects include increasing glucose transport, regulating glycolytic enzymes, normalizing plasma glucose levels and activities of insulin regulated enzymes in diabetic rats. Our goal was to examine effects of sodium vanadate and sodium selenate on fatty acid biosynthesis in two insulin responsive systems: Isolated rat hepatocytes …


Expression Of Integrated And Methylated Hiv-Ltr In Human T-Cells And Monkey Kidney Cells By Frog Virus 3 Infection, Celene M. Spangler Aug 1994

Expression Of Integrated And Methylated Hiv-Ltr In Human T-Cells And Monkey Kidney Cells By Frog Virus 3 Infection, Celene M. Spangler

Masters Theses

DNA methylation has been implicated in the suppression of transcription of a large spectrum of eukaryotic genes. Frog virus 3 (FV3) contains genomic DNA that is the most extensively methylated of all known animal viruses. However, FV3 gene expression is tightly regulated in a sequential fashion in infected cells. Therefore, FV3 must have evolved mechanism(s) to overcome the inhibitory effects of DNA methylation. FV3 has been shown to induce expression of methylated foreign genes in transient transfections. This study was designed to establish if this FV3 induced expression of methylated genes could be demonstrated in stable cell lines which contain …


Microvascular Corrosion Casting Of The Rat Mandibular Joint: A Technical Approach, Etienne Piette, Alois Lametschwandtner Jul 1994

Microvascular Corrosion Casting Of The Rat Mandibular Joint: A Technical Approach, Etienne Piette, Alois Lametschwandtner

Scanning Microscopy

The rat mandibular joint is a ginglymoarthrodial joint deeply hidden under the zygomatic process of the squamosal bone. This joint was studied by scanning electron microscopy (SEM) of microvascular corrosion casts in 47 adult rats. Six additional rats were injected with India ink and thick sections of the joint area were examined by light microscopy. The small size of the joint (2.5 mm x 1.5 mm in occlusion), the existence of two slit-like joint compartments, the close proximity of bones and soft tissues in a mobile structure, and the intimate relationships of the joint with adjacent skeletal muscles made the …


Ultrastructural Features Of Apoptosis, Elisabetta Falcieri, Pietro Gobbi, Loris Zamai, Marco Vitale Jul 1994

Ultrastructural Features Of Apoptosis, Elisabetta Falcieri, Pietro Gobbi, Loris Zamai, Marco Vitale

Scanning Microscopy

Apoptosis is a gene-directed physiological and programmed process of cell deletion aimed at the regulation of tissue and organ development. It affects different cell types and is triggered by a variety of stimuli all inducing closely comparable structural changes. Despite the deeply different morphology and metabolism of the cell models and the various inducers and their initial effects, a convergence seems to take place in a common metabolic pathway that, in most cases, involves the activation of a Ca2+ dependent endonuclease. A growing body of data is now available on the molecular events that lead to DNA damage. DNA …


Scanning Electron Microscopy And Energy-Dispersive X-Ray Microanalysis Studies Of Several Human Calculi Containing Calcium Phosphate Crystals, Tetsuo Kodaka, Kazuhiro Debari, Tsuneyoshi Sano, Masayuki Yamada Jul 1994

Scanning Electron Microscopy And Energy-Dispersive X-Ray Microanalysis Studies Of Several Human Calculi Containing Calcium Phosphate Crystals, Tetsuo Kodaka, Kazuhiro Debari, Tsuneyoshi Sano, Masayuki Yamada

Scanning Microscopy

Human calcium phosphate calculi: two sialoliths, a urolith, a rhinolith, and a tonsillolith were investigated by scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDX). The sialoliths and urolith had appositional shells with thick cortices, respectively, around several nuclei composed of calcospherulites and a rubber-film fragment. The rhinolith had a thin cortex with appositional laminations around a glomerulus-like mass of calcified cotton-like strings. The tonsillolith had a rough cortex with appositional laminations. Its porous interior was composed of numerous calcified conglomerates with microorganisms and calcified masses with fine appositional laminations around the conglomerates. The major crystals were identified as biological …


An X-Ray Microanalytical Study On The Effects Of Ouabain And N-Ethyl Maleimide On The Elemental Concentrations In Malpighian Tubule Cells Of Locusta, Natalia Pivovarova, John H. Anstee, Ken Bowler Jul 1994

An X-Ray Microanalytical Study On The Effects Of Ouabain And N-Ethyl Maleimide On The Elemental Concentrations In Malpighian Tubule Cells Of Locusta, Natalia Pivovarova, John H. Anstee, Ken Bowler

Scanning Microscopy

X-ray microanalysis was used to study elemental distribution in Malpighian tubule cells of Locusta migratoria and how these are affected by the replacement of bathing medium K+ with Rb+ and by inclusion of the transport inhibitors ouabain and n-ethyl maleimide (NEM) in standard (K+-containing) and Rb+-Ringer (K+-free) solutions. Incubation of tubules in standard Ringer containing 1 mM ouabain dramatically affected the intracellular levels of K and Na. The intracellular K concentration fell and Na concentration increased in all regions studied. Despite this, a gradient of increasing K concentration from basal to apical …


The Mayfly Newsletter, Peter M. Grant Jul 1994

The Mayfly Newsletter, Peter M. Grant

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy Jul 1994

Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy

Biology Faculty Publications and Presentations

Data were collected on annual (1980-1983) and seasonal (spring vs. summer) variation in reproduction by the double-brooded Eastern Phoebe (Sayornis phoebe) to test the proposal that phoebes modify reproductive patterns on a seasonal basis and switch from being brood survivalists in spring to brood reductionists in summer. Clutch size did not differ between spring and summer broods nor among years, but spring nests fledged one more nestling than summer nests. In 1981 breeding began earlier, eggs were larger, and nestlings grew faster than in all other years. Clutch size and egg mass within spring clutches increased seasonally. Egg mass was …