bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of the electrophoretic mobility mutation in the N protein of the tsD1 mutant of vesicular stomatitis virus New Jersey serotype
Authors: Brown Earl , Prevec Ludvik
Published: December 2009

Some isolates of the temperature sensitive mutant tsD1 of complementation group D of vesicular stomatitis virus of New Jersey serotype have a nucleocapsid (N) protein which shows an increased electrophoretic mobility on sodium dodecyl sulfate –polyacrylamide gel electrophoresis (SDS–PAGE) when compared with wild type. Utilizing techniques involving specific chemical cleavage at tryptophan or methionine residues, as well as enzymatic cleavage with carboxypeptidases A and B, we have determined that residues near the carboxyterminus are responsible for the electrophoretic difference of the mutant protein. We have further shown that there are no differences in the tryptic peptides of the mutant compared with the wild type or a non-ts revertant in this region of the protein. We have identified a tryptic peptide located outside the relevant carboxyterminal region which is distinct in mutant and revertant. We conclude that the mutation producing the aberrant electrophoretic mobility of N protein of the tsD1 mutant is a missense point mutation located at least 40 amino acid residues from the carboxyterminus and which interacts with a more proximal carboxyregion so as to influence electrophoretic mobility on SDS–PAGE.
Analysis of the expression of cloned genes using an Escherichia coli cell-free system
Authors: See Yew Phew , Glick Bernard R.
Published: December 2009

An Escherichia coli coupled transcription–translation cell-free system, which is efficient in the synthesis of proteins directed by exogenously added DNA, is described. These cell-free extracts direct protein synthesis against a low background of endogenous protein synthesis providing a means for analyzing the expression of isolated genes. This is especially important when using restriction enzyme-linearized DNAs which are less efficient templates than circular DNAs. This cell-free system has been used to study the expression of the proteins coded by plasmids pBR322 and pBL101.
Effects of glycerol and fructose on purine synthesis de novo and on PP-ribose-P availability in rat liver cells
Authors: Rosiers Christine Des , Lalanne Marcel , Willemot Joan
Published: December 2009

Incubation of freshly isolated rat liver cells with glycerol resulted in an initial decrease, followed by an increase in purine synthesis de novo and in PP-ribose-P availability. The magnitude of these effects was dependent on the concentration of glycerol; as it increased, the initial period of latency or inhibition was prolonged, and the extent of the subsequent stimulation was greater. The intracellular Pi concentration and the [14C]ATP/[14C]ADP ratio were also initially decreased in these cells, and they too returned subsequently to normal values. All these changes were similar to those induced by fructose under the same conditions. The increase in PP-ribose-P availability always preceded that in purine synthesis de novo, indicating that, under most circumstances, PP-ribose-P availability is limiting for purine synthesis de novo. Finally, PP-ribose-P synthesis in these cells varied in parallel with the intracellular Pi concentration and with the ATP/ADP and ATP/AMP ratios.
Large-scale production of citrate synthase from a cloned gene
Authors: Duckworth Harry W. , Bell Alexander W.
Published: December 2009

Starting with a colicin E1 resistance recombinant plasmid which contains gltA, the gene for citrate synthase in Escherichia coli, we have constructed an ampicillin-resistance plasmid containing the gltA region as a 2.9-kilobase-pair insert in the tetracycline-resistance region of pBR322. Escherichia coli HB101 harbouring this plasmid, when grown on rich medium containing ampicillin, contains citrate synthase as about 8% of its soluble protein. The enzyme has been purified from this rich source and is identical to the chromosomal enzyme prepared previously in every property tested, except for specific activity, which is 64 U∙mg−1 as compared with 45–50 U∙mg−1 previously obtained. The N-terminal sequences of both enzymes are reported, and they are identical up to residue 16 at least. The overall yield of pure enzyme, starting with the cells grown in 15 L of medium, is 600–800 mg.
Modelling the spatial population dynamics of arctic foxes: the effects of red foxes and microtine cycles
Authors: Shirley Mark D.F. , Elmhagen Bodil , Lurz Peter W.W. , Rushton Steve P. , Angerbjörn Anders
Published: December 2009

The Fennoscandian arctic fox ( Vulpes lagopus (L., 1758)) population is critically endangered, possibly because of increased interference competition from red foxes ( Vulpes vulpes (L., 1758)) and fading cycles in microtine rodents, which cause food shortage. It is not known how these factors drive arctic fox population trends. To test their role in arctic fox decline, we developed a spatially explicit and individual-based model that allowed us to simulate fox interactions and food availability in a real landscape. A sensitivity analysis revealed that simulated arctic fox population size and den occupancy were strongly correlated with fecundity and mortality during the microtine crash phase, but also with red fox status. Model simulations suggested that arctic fox population trends depended on microtine cycles and that arctic fox distributions were restricted by red fox presence. We compared the model predictions with field data collected at Vindelfjällen, Sweden. The model recreated the observed arctic fox trend only with the inclusion of arctic fox avoidance of red fox home ranges. The results indicate that avoidance behaviours can affect population trends and hence that relatively small numbers of red foxes can have a strong negative impact on arctic fox population size and distribution.
Movement behaviour of adult western toads in a fragmented, forest landscape
Authors: Deguise Isabelle , Richardson John S.
Published: December 2009

Habitat loss and fragmentation are among the best documented explanations for the dramatic declines amphibians are experiencing globally. The western toad ( Anaxyrus boreas (Baird and Girard, 1852)) is an IUCN red-listed species whose distribution range has been significantly affected by habitat modification. We used radiotelemetry to follow daily, postbreeding movement patterns of 23 adult male toads in a fragmented landscape near Vancouver, British Columbia, Canada, composed of forest patches and small, recent clearcuts (~5 ha). Results showed that toads in forests oriented towards edges of clearcuts from at least as far as 150 m. Greater than 60% of toads released in forest patches chose to enter the clearcuts from adjacent forests, indicating high boundary permeability. Net displacement distance was not significantly reduced in these clearcuts; however, movement rates were significantly lower on clearcuts than in forest. This indicates that there is no structural impediment to movements; however, there still could be fitness consequences or an interaction with summer weather. Toads also used roads for their movement more frequently than at random relative to their area. These results suggest that the western toad’s movements may not be negatively affected by small-scale forest harvesting at our latitude during the spring.
Observations on a nematode parasite of Aedes vexans (Diptera:Culicidae) in Manitoba
Authors: Harlos J. , Brust R. A. , Galloway T. D.
Published: December 2009

A mermithid nematode, commonly found in Aedes vexans adults in southern Manitoba, was reared through four successive generations in the laboratory. Young larvae were readily infected by preparasites. The mean infection rate was 40% when equal numbers of larvae and preparasites were exposed.Very little development of the nematode occurred until the middle of the fourth instar and then it accelerated in the pupa and adult stages. The median time to the postparasitic juvenile stage was 14 days after host eclosion.Both male and female mosquitoes were suitable hosts for the nematode. Host diet, host sex, and multiple parasitism affected the size of the postparasites. A blood meal was not required by the female mosquito for development of the parasite, but a higher proportion of female postparasites was obtained when blood was given.Pools containing infected larvae were found in Winnipeg. Aedes vexans larvae were heavily parasitized, whereas Aedes dorsalis in the same pools had only light infections. Aedes vexans was the best host out of several species tested in the laboratory.
The role of photoperiod and temperature in the initiation of reproduction in the terrestrial isopod Oniscus asellus Linnaeus
Authors: McQueen D. J. , Steel C. G. H.
Published: December 2009

Terrestrial isopods collected in the fall after reproduction and moulting had stopped were maintained in the laboratory at combinations of four temperatures (12, 14, 16, and 18 °C) and six daylengths (8, 9, 10, 11, 12, and 14 h light per day). It was found that increased temperature decreased the time elapsed between the end of reproduction in the fall and its reiniliation the next spring. Increased temperature also decreased the development time for larvae in the brood pouch. The data indicated that a "critical" daylength existed so that animals grown at daylengths > 12 h light reproduced earlier in the spring than animals grown at < 12 h light. Temperature change did not alter this threshold effect. Finally, daylength did not alter development time for larvae within the brood pouch. This work is the first showing photoperiodic response curves for the initiation of reproduction in any crustacean.
Psychrolutes sio, a new psychrolutid fish (Scorpaeniformes) from the southeastern Pacific
Authors: Nelson Joseph S.
Published: December 2009

Psychrolutes sio, a new species of Psychrolutidae from off northernmost Chile, is described from two specimens trawled at about 770–1150 m. The holotype is deposited in the Scripps Institution of Oceanography (SIO 72-184). The only large specimen, the 22.9-cm holotype, differs most conspicuously from the other two species of the genus Psychrolutes in having the head and body color a uniform brown, skin thin, lateral line pores in small but distinct tubes, and jaws equal. Psychrolutes sio represents the first record of the genus Psychrolutes to be recognized from the Southern Hemisphere. However, future studies may indicate that other southern psychrolutids of the genera Neophrynichthys and Cottunculoides should also be assigned to Psychrolutes.
Métabolisme protéique et parasitisme chez le crabe Carcinus maenas. Effets de Sacculina carcini (Crustacé, Rhizocéphale) sur les protéines sériques et épidermiques de l'hôte
Authors: Andrieux Nicole , Herberts Charmaine , Frescheville Jacques De
Published: December 2009

The serum and epidermal proteins of healthy crabs and parasitized crabs at various stages of infestation by Sacculina carcini have been compared. All protein groups of healthy crabs were found in sacculinized animals. For crabs with internal parasites and that molt at regular intervals the proteinogram did not show any alteration. However, in animals with external Sacculina, the molts were inhibited and the molting cycle was stopped before apolysis; the proteins implicated in the molting processes tend to disappear. For the other fractions, the proteinogram of such animals is much more similar to that of crabs at the beginning of premolt than to that of crabs during intermolt.
Effects of sexual maturation and sex steroid hormone treatment on the temperature preference of the guppy, Poecilia reticulata (Peters)
Authors: Johansen Peter H. , Cross Jennifer A.
Published: December 2009

In a horizontal temperature gradient, male guppies prefer a significantly lower temperature (24.5 °C) than females (28.2 °C) or juveniles (28.1 °C). Treatment of juveniles and females with testosterone lowers their preferred temperature to that of males. The reduction in the preferred temperature of testosterone-treated juveniles can occur without the development of male secondary sexual characters. Estrogen treatment of juveniles is without effect, as is treatment of males with estrogen or testosterone. It is postulated that testosterone acts at the level of the hypothalamic thermoregulatory centre.
Aspects ultrastructuraux et cytochimiques des hématies nucléées de deux Annélides Polychètes Notomastus latericeus Sars et Glycera convoluta Keferstein
Authors: Sean K. E. , Boilly B.
Published: December 2009

The structure and cytochemistry (pseudoperoxidase activity and iron content) of the nucleated erythrocytes of two polychaetes, Notomastus latericeus Sars and Glycera convoluta Keferstein, have been investigated using light and electron microscopy. These cells contain few cytoplasmic organelles but do possess iron-rich structures in vacuoles and free in the cytoplasm. Both species show a pseudoperoxidase activity throughout the cytoplasm and, in the case of Notomastus, in the nucleus as well. The cytological and cytochemical aspects of these cells suggest a low metabolism and a limited lifetime, particularly in Notomastus.
Répartition spatiale, cycle saisonnier et croissance de Mysis litoralis (Banner, 1948) (Mysidacea) dans un fjord subarctique
Authors: Ladurantaye Réjean de , Lacroix Guy
Published: December 2009

An isolated and practically unknown population of Mysis litoralis was sampled biweekly with plankton nets in the Saguenay fjord, in May–October 1975 and April–May 1976. In April and May, this arctic mysid is almost absent upstream and occurs mainly in the central and lower parts of the fjord. From June to October, it is restricted in distribution to the lower part of the fjord. There, M. litoralis inhabits deep waters (100–200 m)of< 5 °C in May and June, but is found mainly in shallower (up to 5 m) and warmer waters from July to October, regardless of the age of individuals. The vertical salinity range in the fjord is 2–3‰. Reproductive activity occurs only once a year, in late October or early November, and young mysids, then averaging a length of 3.8 mm. are released from the brood pouch in April–May, There is evidence that the number of young (33–113) in the marsupium varies with the size of the female. From June to September individuals of the new stock grow rapidly to a length of 15 mm. As early as October, almost all the individuals have attained the average length of the parental stock, and are sexually mature, apparently due to the favourable temperature and food conditions of the downstream area. Some individuals of the breeding population may survive to the following year.
Effects of radiotransmitters on the meadow vole, Microtus pennsylvanicus
Authors: Webster A. Bruce , Brooks Ronald J.
Published: December 2009

Investigations were carried out in both laboratory and field to determine the effect of radiotransmitters on survival, activity, and body weight in Microtus pennsylvanicus. In the laboratory, feeding rate of voles was depressed for 24 h after they were tagged with a radiotransmitter, and wheel-running activity was reduced for 72 h. Field evidence suggested that activity of transmitter-tagged voles was depressed during the first 24 h after their release, but this effect did not persist for more than 24 h after release. In winter, but not in summer and fall, weight and survival of transmitter-tagged voles were reduced compared with voles not tagged with transmitters. Voles in winter typically lost 2 to 3 g after being tagged with transmitters. Lower survival of transmitter-tagged voles in winter may have been due to greater susceptibility to predation.
A world review of the liliaceus species group in the genus Typhlodromus Scheuten (Acarina: Phytoseiidae)
Authors: Chant D. A. , Shaul E. Yoshida
Published: December 2009

The liliaceus species group in the genus Typhlodromus is newly proposed and reviewed on a world basis. Characteristics of the group are described. Keys to the species in the group are presented and descriptions of the adult females of each of the six species are given.
Comparative foraging behaviour and efficiency of adult and juvenile great blue herons
Authors: Quinney T. E. , Smith P. C.
Published: December 2009

Foraging behaviour and efficiency of adult and newly fledged juvenile great blue herons, Ardea herodius L., were studied at the Gaspereau River estuary. Nova Scotia, in July and August 1977 and 1978. Pace and strike rates of adults and juveniles were similar, whereas capture and probe rates differed markedly. Adults captured prey more successfully than juveniles but the ability of the latter improved with age. Foraging success of adults was greater in flocks of more than five individuals. In contrast, juvenile success does not seem related to flock size. Ninety-eight percent of the identified prey were flounder Liopsetta putnmi Gill. Handling time of small prey items was the same for adults and juveniles but juveniles took much longer to swallow medium-sized prey than adults did.
Energy and protein intake in relation to growth of suckling black-tailed deer fawns
Authors: Sadleir R. M. F. S.
Published: December 2009

Milk and solid food consumption of energy and protein were measured in suckling Odocoileus heminonus columbianus fawns to 3 months of age. Fawns 7 to 10 days old consumed 175 g milk/kg0.75∙body weight∙day−1 which declined to 40 g/kg0.7S∙day−1 by 61 to 70 days. Mean daily digestible energy intake of milk and solids was 247 kcal/kg0.75∙day−1 (1 cal = 4.1868 J) and protein intake was 10.7 g/kg075∙day−1. Fawns started effective eating of solids around 30 days and by 90 days >80% of their energy intake was from solids. Some does continued to lactate for another 4 months, indicating that the metabolic and behavioural aspects of weaning can be separated in time. Growth for the first month of age was positively correlated with milk consumption, and growth rates up to 1,2, and 3 months were inversely correlated with birth weights but not to 4 months or older. Growth rates to 2 months were positively correlated with maternal growth rates to the same ages suggesting a genotypic and (or) prenatal effect on growth of fawns.
The geographical distribution of diplostomiasis (Trematoda: Strigeidae) in fishes from northern Quebec, Canada, in relation to the calcium ion concentrations of lakes
Authors: Curtis Mark A. , Rau Manfred E.
Published: December 2009

All 12 species of fishes collected from lakes on the Quebec–Labrador geosyncline and the surrounding Canadian Shield exhibited diplostomiasis. Based primarily on data from Salvelinus fontinalis, Catostomus catostomus, and C. commersoni, the infection was rare or absent in lakes with low calcium ion concentrations but apparently ubiquitous in waters high in calcium. The occurrence of this disease reflects the local distribution of the snail intermediate host Lymnaea arctica, which appears restricted to waters with calcium levels of more than about 5 ppm. Such lakes characteristically overlie rock rich in dolomite. This information suggests that the distribution of diplostomiasis in northern Quebec can be predicted from existing geological maps.
Distribution and specificity of Mermithidae (Nematoda) infecting Simuliidae (Diptera) in Newfoundland
Authors: Colbo M. H. , Porter G. N.
Published: December 2009

A number of simuliid populations infected with mermithids were studied to elucidate the nematode's life history patterns and the effect of this on the infected host's distribution. Some of the mermithids were very host specific, while others infected all simuliid species exposed to some degree. An extensive study showed that mermithids infecting Prosimulium mixtum failed to infect Stegopterna mutata which may have been due to the preparasites inability to recognize St. mutata as a potential host, or due to host behaviour, rather than microdistribution or physiology.In mermithid species where the majority complete their parasitic phase and emerge from the larval simuliid, the heaviest infections occur towards the downstream end of the host distribution. On the other hand those mermithid species which emerge only from adult simuliids have a high infection rate in the larval simuliids at the upstream end of host distribution. Infection occurs in the early simuliid instars, primarily first and second, with perhaps some in the older larvae. The rate of infection and the number of larvae per host changed between the time of simuliid hatch and the final host instar at most sites. However, the infection pattern in late instar larvae in any one stream appeared to be relatively stable from year to year.In the present study all mermithid infections of adult hosts were confined to the female fly irrespective of the mermithids life history pattern.
Evidence for the presence of rat a α1-acid glycoprotein in granuloma tissue: a fluorescence microscopy study
Authors: Jamieson J. C. , Turchen B. , Huebner E.
Published: December 2009

Turpentine granulomas were produced in rats and examined histologically and for the presence of rat albumin and α1-acid glycoprotein using fluorescent labelled antibody to these proteins. Examination of granulomas showed the presence of a connective tissue region of granuloma tissue; this region stained strongly with fluorescent anti-α1-acid glycoprotein whereas there was little staining with fluorescent antialbumin. These results suggest that α1-acid glycoprotein is located at the inflammatory site and may be involved in some aspect of the inflammatory process.
Etude des effets phytoestrogéniques et phytotoxiques de la végétation de milieux ouverts sur la souris de laboratoire
Authors: Bergeron Jean-Marie , Goulet Marie
Published: December 2009

Dietary experiments have been designed to emphasize the phytoestrogenic and phytotoxic effects of certain open-land plants. The 30 plant species given as food did delay the growth of the animals. Some nine species of plant, including red clover (Trifolium pratense), have actually accelerated uterine growth in experimental animals. Moreover, 12 species produced an atrophy of the kidneys; some of those species also possess estrogenic properties. Some of those plants are already known for their estrogenic or toxic effects, but most of the plants used seem to have some effect. We examined the possibility of using this experimental method in a study of population dynamics of wild small mammals in order to determine the impact of the plants in a natural environment.[Journal Translation]
Distribution of the middorsal stripe dimorphism in the wood frog, Rana sylvatica, in eastern North America
Authors: Schueler Frederick W. , Cook Francis R.
Published: December 2009

The frequency of the middorsally striped morph of Rana sylvatica in Ontario and Manitoba varies from absence in southern Ontario to 80% on the coast of Hudson Bay, with a general value of 20–30% in the boreal forest, a rise to 50% on the forest–grassland ecotone in southern Manitoba, and a decline westward to 20% on the edge of the prairies. This morph is rare in the northeastern United States and Maritime Canada. The suggested relationship between its frequency and the "grassiness" of the background on which predators view it is reexamined, and it is suggested that a linkage with earlier transformation as demonstrated in Eurasian species may explain certain anomalies.
Coelomomyces stegomyiae var. chapmani var.nov. with new host and locality records for Coelomomyces from mosquitoes of Taiwan
Authors: Laird Marshall , Nolan Richard A. , Lien J. C.
Published: December 2009

Coelomomyces stegomyiae var. chapmani var.nov. is described from Tripteroides bambusa, Topomyia yanbarensis, Aedes albopictus, and Armigeres subalbatus. Aedes malikuli may also be infected by C. stegomyiae; however, the fungal material could not be identified with certainty beyond the generic level. Coelomomyces quadrangulatus was present in Uranotaenia sp. (near recondita); Coelomomyces macleayae in T. bambusa, Aedes japonicus ssp. shintienensis, and Aedes alcasidi; and Coelomomyces omorii in Culex annulus. The C. omorii sporangia from Taiwan show intermediate characteristics in comparison with sporangia of the typical variety from Japan and "Coelomomyces dubitskii" from Kazakhstan, USSR. All host species records, except for A. albopictus, two host genera records (Tripteroides, Topomyia), and all locality records are new.
Arachidonic acid requirement for two species of Culiseta reared on synthetic diet
Authors: Dadd R. H. , Friend W. G. , Kleinjan J. E.
Published: December 2009

Culiseta incidens and Culiseta inornata larvae were successfully reared under aseptic conditions on a completely defined chemical medium. Arachidonic acid is an essential nutrient for both species. Larvae of C. incidens would develop and pupate in the absence of this fatty acid but emergence was impaired and none of the resulting adults could fly. None of the C. inornata larvae reared on diets lacking arachidonic acid became adult. Many of the C. inornata adults that emerged from diets containing this fatty acid could fly. Amino acid concentrations in the diet of 0.9% were superior to 1.4% for C. inornata. Asparagine was shown to be an essential nutrient for C. incidens; its nutritional effects were not tested on C. inornata.
Circadian rhythms in the brown bullhead, Ictalurus nebulosus (Teleostei). Evidence for an endogenous rhythm in feeding, locomotor, and reaction time behaviour
Authors: Eriksson Lars-Ove , Veen Theo van
Published: December 2009

Locomotor and feeding activity was investigated under(1) 12 h light(L): 12 h dark(D)and 16 h L: 8 h D, (2) 24 h D and 24 h L, and (3) dark pulses (0.75 h L: 0.25 h D), in the brown bullhead (Ictalurus nebulosus). In addition to locomotor and feeding activity, reaction time (latency time on lights-off and lights-on) was also measured.Fish subjected to a light–dark regime showed nocturnal behaviour, in many cases with a positive phase angle difference (i.e., the animals ceased their activity several hours before lights-on). Further, the actograms showed, as expected, a distinct 24 h rhythm. Only 2 brown bullheads out of 15, subjected to constant conditions, showed a circadian component in the locomotor activity, which could only be detected by frequency analysis.Nine out of 12 animals subjected to dark pulses (0.75 h L: 0.25 h D) showed a free-running circadian rhythm (approximately 23 h) in locomotor activity and 2 out of 3 showed such a rhythm in feeding activity. Observations and measurements of reaction time on leaving and re-entering the shelter after lights-off and lights-on (0.75 h L: 0.25 h D) showed also that this parameter has a circadian course. Measurements performed a fortnight later showed a similar, but less pronounced, pattern of behaviour.Dark pulses are thought to prevent rapid dissociation of a flexible multioscillatory circadian system in the brown bullhead.
Effects of castration on open-field behaviour and aggression in male meadow voles (Microtus pennsylvanicus)
Authors: Turner Brian N. , Iverson Stuart L. , Severson Kenneth L.
Published: December 2009

A series of three experiments tested the hypothesis that castration would result in altered open-field behaviour and aggression in male meadow voles. The open-field behaviour of laboratory-reared voles was not affected, and that of wild-captured laboratory-housed animals showed only one significant difference. However, in free-ranging voles, recaptured at intervals for testing, castration resulted in significantly reduced intermale aggression, and significantly decreased activity and increased urination in the open field. Thus, only the results from the experiment using free-ranging voles indicate a significant castration effect, and we suggest the lack of effect in laboratory-housed animals may be due to changes in factors including photoperiod, social milieu, and season.The changes in aggression and open-field behaviour in the wild animals are in agreement with interpretation of previous field studies of intact male voles, which demonstrated changes in these two behaviours at the onset of the breeding season. Among free-ranging meadow voles, therefore, the decreased hormone levels resulting from castration led to changes in these behaviours opposite to those observed in the spring when hormone levels increase with seasonal reproductive maturity. These behaviours thus appear to be at least partially dependent upon circulating testosterone levels in wild voles.
Sterilization of red cotton bug with tepa: effects on longevity, duration of copulation, number of matings, and sexual competitiveness
Authors: Sehgal S. S. , Maheshwari S. C. , Chaudhary K. D.
Published: December 2009

Tepa sterilization of red cotton bug, Dysdercus koenigii F., during the third nymphal instar did not affect the survival, duration of copulation, number of matings, and sexual competitiveness of the adults. These data suggest that tepa sterilization can be used as a tool for the suppression of populations of this insect.
Ultrastructure of scent glands in larvae of Apateticus bracteatus (Hemiptera: Pentatomidae) and chemical composition of the secretion
Authors: Percy Jean , MacDonald J. A. , Weatherston J.
Published: December 2009

The three dorsal abdominal glands in larvae of Apateticus bracteatus (Pentatomidae) secrete a mixture of compounds. Major volatile constituents of the secretion are identified, herein, as tridecane and 2-octenal. There are also trace amounts of 2-hexenal and two other unidentified compounds.Each of the glands has paired orifices that are located between tergites 3/4, 4/5, and 5/6, but only the most anterior gland is paired. In anterior glands of midinstar larvae, glandular cells associated with ducts, and interstitial glandular cells are distributed along the ventral walls of the reservoirs. In posterior glands, columnar glandular cells are located in the anterior dorsal wall of the reservoirs; secretory cells associated with ducts, and nonglandular interstitial cells are distributed throughout the ventral and posterior walls of the reservoirs. The interstitial glandular cells of the anterior gland and the columnar glandular cells of the middle and posterior glands contain cytoplasmic organelles characteristic of lipid-producing cells. In all glands the secretory cells associated with ducts secrete lipids. Evidence indicating the importance of Golgi and ER in secretion synthesis is presented. The reservoirs and ducts have a thin cuticular lining.The bearing of the results on present ideas of gland function in Heteroptera is discussed.
Mating in the gastropod mollusk Aeolidia papillosa: behavior and anatomy
Authors: Longley Alison J. , Longley Roger D.
Published: December 2009

Mating behavior and related reproductive anatomy were studied in the hermaphroditic gastropod Aeolidia papillosa. This species is androdiaulic, not triaulic as previously reported, since one duct serves for both egg laying and sperm reception. Aeolidia papillosa is unusual among the larger opisthobranchs in that its mating is of short duration and can be readily elicited in the laboratory. The form and continuity of the mating sequence appears to be mediated by sensory input, with mouth contact playing an important role. This sequence, which ends with reciprocal sperm transfer, was divided into three phases whose duration could be objectively timed. The transition to the copulatory phase, which completes the behavior, is associated with the mutual proximity of a previously undescribed projection between the male and female openings. The duration of this phase is positively correlated with animal weight but is unaffected by the time since the last mating. Spermatozoa sufficient for 10 or more copulations are present in the ampulla (about 4 × 108 per ampulla); hence copulation time is probably determined by neural timing circuitry which acts independently of the availability of autosperms.
Ultrasound-sensitive neurons descending in the thoracic nervous system of the cricket Teleogryllus oceanicus
Authors: Pollack Gerald S.
Published: December 2009

Responses were recorded from descending, ultrasound-sensitive interneurons in the promesothoracic connectives of the cricket Teleogryllus oceanicus. The cells were most sensitive to sounds with frequencies of 20–50 kHz. Cells differed in their directionality characteristics; some were most sensitive to ipsilateral sounds, and some were most sensitive to contralateral sounds. Consideration of other response characteristics, such as latency, spiking pattern, and response amplitude, suggests that both directionality classes may contain several neuronal types. Many, though not all, of the cells ceased responding when the connections between the prothoracic ganglion and the head ganglia were severed. Two-tone experiments were performed, and these demonstrated that the responses to high frequency sounds were suppressed by simultaneously presented low frequency sounds. Suppressing frequencies near that of the species' calling song were most effective. The presumed roles of neurons sensitive to high frequency sounds are compared between T. oceanicus and other species.
The effects of 5-hydroxytryptamine on glucose absorption by Hymenolepis diminuta (Cestoda) and by the mucosa of the rat small intestine
Authors: Gruner S. , Mettrick D. F.
Published: December 2009

The effect of 5-hydroxytryptamine (5-HT), over a concentration range of 0.1–2.0 mM, on in vitro regional glucose uptake by Hymenolepis diminuta, in which the incubation media contained 1–20 mM glucose, was studied in 15-day-old worms. In the anterior region of the strobila, 5-HT concentrations of 0.5 mM or greater significantly enhanced glucose uptake at all concentrations of glucose. In the posterior region of the strobila, 5-HT had no stimulatory effect on glucose uptake. In every case, glucose uptake was reduced compared with the corresponding values for the anterior region of the worm strobila. Increasing glucose concentrations significantly increased glucose utpake by the anterior and posterior regions of the strobila. Mediated (active) transport of glucose in the anterior region of the strobila was increased over the range 0.1–0.5 mM 5-HT; above 0.5 mM glucose uptake decreased. Increasing concentrations of 5-HT above 0.25 mM significantly increased the passive component of glucose uptake (Kd). Using an in vivo perfusion technique, the effect of 5-HT on glucose uptake in the jejunum, proximal ileum, and distal ileum of uninfected and parasitized rats was determined. In uninfected rats, 5-HT had no significant stimulatory effect on glucose uptake in all three regions of the intestine. In the parasitized intestine, 5-HT significantly decreased glucose uptake; in the absence of 5-HT glucose uptake was significanty enhanced in the ileum when compared with uninfected controls.
Trypanosoma spp. (Protozoa: Kinetoplastida) in Hylidae (Anura) from eastern North America, with notes on their distributions and prevalences
Authors: Woo Patrick T. K. , Bogart Jim P.
Published: December 2009

Using the haematocrit centrifuge technique, four species of trypanosomes were detected in the blood of 46 of 275 hylids (Pseudacris triserita, Hyla crucifer, Hyla versicolor, Hyla chrysocelis, and Hyla avivoca) from eastern North America. Morphological identification of three (Trypanosoma andersoni, Trypanosoma grylli, and Trypanosoma pipientis) of the four species was confirmed by inoculations into laboratory-raised frogs. Trypanosoma andersoni and T. grylli were detected in H. versicolor, H. avivoca from Ohio, and H. chrysocelis from South Carolina. The latter two anurans represent new host records and localities for the two trypanosomes. Additional new host locations for T. andersoni and T. grylli in the United States are Michigan, West Virginia, and South Carolina. Trypanosoma pipientis was recorded from P. triserita, H. crucifer, and H. versicolor in Ontario; this extends the host range for the trypanosome from the Ranidae to the Hylidae. Trypanosoma ranarum, a common parasite of Rana spp., was found in H. versicolor from Ontario and Quebec. Since no cross inoculation was conducted, the identification of T. ranarum in the hylid is tentative.
How does the brain control the pituitary's release of antifreeze synthesis inhibitor?
Authors: Fletcher G. L. , King M. J. , Hew C. L.
Published: December 2009

Previous studies of winter flounder (Pseudopleuronectes americanus) demonstrated that the pituitary inhibits the synthesis of antifreeze proteins during the summer and that the inhibition is removed with the approach of winter. Assuming that the pituitary is under the control of the central nervous system, the question posed was, Does the central nervous system stimulate the release of the pituitary antifreeze inhibitory factor during the summer or inhibit its release during the winter? Two experiments were carried out. In the first, flounder were hypophysectomized and a number of them were given pituitary autotransplants prior to the spring loss of plasma antifreeze. During July, flounder containing functional autotransplants had lost the capacity to synthesize antifreeze proteins and their plasma antifreeze activity had disappeared. In the second experiment, hypophysectomy and pituitary transplantation was carried out in the fall prior to the winter onset of antifreeze biosynthesis. Flounder containing functional auto- or homo-transplants showed no evidence of plasma antifreeze activity, whereas intact controls and hypophysectomized flounder had levels typical of winter fish. These results indicate that the central nervous system normally inhibits the pituitary glands release of antifreeze inhibitor during the winter.
Secondary production of four sublittoral, soft-sediment amphipod populations in the Bay of Fundy
Authors: Wildish D. J.
Published: December 2009

Estimates of secondary production by cohort summation of losses and size–frequency methods were made on the four most abundant amphipods at an 80 m deep station on a soft sediment in the southwestern mouth of the Bay of Fundy. Production and annual turnover ratios (production:biomass ratio (P:B), in parentheses) for the 1978 year class, expressed as grams wet preserved weight per square metre per year, were as follows: Haploops fundiensis, 0.505 (1.3); Photis reinhardi, 0.370 (2.8); Casco bigelowi, 1.210 (2.5); Harpinia propinqua 0.066 (3.1). The P:B ratios found were closest to those calculated by the empirical method of Robertson when an accurate estimate of life-span was available.
Significance of activity and movement in the yellow-bellied slider turtle (Pseudemys scripta)
Authors: Morreale Stephen J. , Gibbons J. Whitfield , Congdon Justin D.
Published: December 2009

Activity levels throughout the year and movement patterns of individually marked slider turtles (Pseudemys scripta) were studied in three aquatic systems on the Savannah River Plant in South Carolina. An hypothesis was proposed to explain the differential movements and activity levels of the sexes, based on the assumption that reproductive strategies modify movements and activity. Males were more active than females in early spring and late autumn. Significantly more males exhibited both terrestrial movements and aquatic movements >1 km. In addition, the longest movements were made exclusively by males. These data support the hypothesis that patterns of activity in this species are associated with differential reproductive strategies of the sexes.
Salinity tolerances and preferences of fry of two species of sympatric sticklebacks: possible mechanisms of habitat segregation
Authors: Campeau Suzanne , Guderley Helga , Fitzgerald Gerard
Published: December 2009

During their period of reproductive activity, the sticklebacks Gasterosteus aculeatus (trachurus) and Gasterosteus wheatlandi show differences in their use of available microhabitats in the salt marshes of the St. Lawrence estuary. Gasterosteus aculeatus is found at all stations along a tidal river, Rivière des Vases, while G. wheatlandi is absent from the sites exposed to freshwater. To determine whether the juveniles of these species have different sensitivities to low salinities which could account for their differential distribution, we examined the salinity tolerances of laboratory-reared fry. Adult G. aculeatus (form trachurus) and G. wheatlandi collected at the mouth of the Rivière des Vases were used as the parental stock. For 1-week-old fry of both species, freshwater represented a marginal environment. Following exposure to freshwater for 96 h, G. aculeatus fry showed a 22% mortality while G. wheatlandi showed a significant decrease in growth. By 5 weeks of age, both species were euryhaline. Despite a wide salinity tolerance, field-collected G. wheatlandi significantly preferred a salinity of 7–14‰ while field-collected G. aculeatus fry showed no significant salinity preference.
The spermatophore of the skipper, Calpodes ethlius (Hesperiidae: Lepidoptera): the sperm sac
Authors: Lai-Fook J.
Published: December 2009

The spermatophore of Calpodes ethlius and its relationship with the bursa copulatrix are described. The sperm sac, which contains the semen, is an elongated cone which occupies the bursal duct and has its opening at the end of this duct near the seminal duct. The sperm sac consists of a relatively insoluble, outer fibrous section and an inner membranous one, derived from the epithelium of the most distal section of the simplex of the male. Infrared and proton magnetic resonance spectroscopy and amino acid analysis confirm the proteinaceous nature of the insoluble component and the absence of chitin. Fluorescence spectroscopy failed to confirm the suspected presence of di- and tri-tyrosine linkages.
A description of the baculum of the bobcat (Felis rufus), with comments on its development and taxonomic implications
Authors: Tumlison Renn , McDaniel V. Rick
Published: December 2009

Examination of the genitalia of male bobcats collected in Arkansas revealed the common occurrence of bacula. The preformed architecture of dense connective tissue and cartilage was evident in juveniles (<1 year). Observed morphological variation in adults was partially ascribed to ontogeny. Maximum dimensions observed were 7.6 mm (length) and 3.1 mm (width). The distal portion of the baculum is a narrow shaft, while the proximal region is expanded and bifurcated ventrally. A vertical septum separates two vacuities in the base of the baculum. These vacuities house the primarily adipose ends of the corpora cavernosa. Morphology of the baculum of the bobcat is similar to that of the European lynx, and, while different from other felids, it indicates validity of the genus Lynx.
Simultaneous measurement of thyroxine and triiodothyronine in trout plasma using a solid-phase radioimmunoassay
Authors: Omeljaniuk R. J. , Cook R. F. , Eales J. G.
Published: December 2009

A solid-phase radioimmunoassay (RIA) employing miniature G-25 Sephadex columns and a single isotope was evaluated for simultaneous measurement of T3 (3,5,3′-triiodo-L-thyronine) and T4 (L-thyroxine) in trout plasma. The method was judged reliable based on the characteristics of the standard curves, the high and consistent recoveries of T3 (87.0 or 86.7%) and T4 ((103 or 98%) added either singly or in combination, low inter- (< 8%) and intra-assay (< 7%) coefficients of variation, predictable values of T3 and T4 after plasma dilution, and acceptable correlations between hormone values obtained using either the simultaneous or single RIA methods ([Formula: see text]; [Formula: see text]). It is concluded that the simultaneous RIA with its savings in time, plasma volume, and reagents can be used to advantage to measure T3 and T4 in plasma of trout and presumably other vertebrates.
Vertical distribution of young pond snails (Basommatophora: Pulmonata): implications for survival
Authors: Boag D. A. , Thomson C. , Es J. Van
Published: December 2009

The vertical distribution of juvenile pond snails (Lymnaea stagnalis and Stagnicola elodes), hatched from egg masses containing known numbers of viable embryos, was recorded daily in artificial containers under outdoor conditions for up to 25 days after hatching. Both species showed an initial vertical movement to the surface of the water with a subsequent return to the bottom sediments after 10–15 days. This pattern was consistent despite differences in the depth of the water column (13 versus 18.5 cm). At 25 days after hatching more than 85% of the population was in the lower half of the container at any one time, almost all being associated with the bottom sediments. The presence of an adult snail of either species in the same container significantly reduced the survival of young snails (from between 85 and 94% to between 1 and 18%). Consumption of the young snails during their first 10 days out of the egg mass, when they were moving to the surface, accounted for the observed differences in survival. Young snails appeared to be ingested incidently by the foraging adults, most often when the former were concentrated at the air–water–glass interface.
Density, movements, and breeding success of female blue grouse in an area of reduced male density
Authors: Lewis Richard A.
Published: December 2009

The density of male blue grouse (Dendragapus obscurus) on a 95-ha area was reduced artificially by approximately 75% in 1982. Density, movements, and breeding success of females on this area in that year were compared with those of females on the same area in 1981 (when density of males was undisturbed) and of females on an unmanipulated control area in 1981 and 1982. A reduction in male density had no apparent effect on the density of either yearling (potential recruits) or adult females, or the daily movements, timing of breeding, and breeding success of females. Home ranges of females were largest when male density was artificially reduced, but not significantly so. The larger home range sizes of females residing in an area with a very low density of males did not seem to result entirely from females searching for males with which to breed. Results of this study suggest that densities of male blue grouse have no apparent effect on densities of females or production of young, and support the hypothesis that densities of females in this species are regulated independently of males.
A study of the relationships between the mouthparts and food habits in several species of freshwater calanoid copepods
Authors: Wong C. Kim
Published: December 2009

The mouthpart morphology of five species of freshwater calanoid copepods was examined with light microscopy and compared with their diets. Limnocalanus macrurus has sharp teeth and stout mouthparts with clawlike setae, structures that have been associated with predaceous feeding. Diaptomus sicilis and Senecella calanoides have blunt teeth and slender mouthparts which seem suited for herbivorous feeding. The mouthparts of Diaptomus shoshone and Epischura laeustris have structures intermediate between those of the other two groups, suggesting an omnivorous mode of feeding. Results of gut analyses show that L. macrurus is predominantly predaceous, D. sicilis is exclusively herbivorous, and the other three species are omnivorous. Thus the diet of S. calanoides is not correctly predicted by the structure of its mouthparts, indicating the limitation of using mouthpart morphology to predict diet.
Morphological adaptations for carrion feeding in four species of littoral or circalittoral lysianassid amphipods
Authors: Sainte-Marie Bernard
Published: December 2009

Mandibles and guts of the lysianassid amphipods Anonyx sarsi, Onisimus littoralis, Orchomenella pinquis, and Psammonyx nobilis differ markedly in shape, size, and presumed function. The larger A. sarsi has broad incisors, tall molars with no triturative area, and a greatly expandable foregut, while the other three species have more narrow incisors, lower molars with triturative areas, and less capacious guts. The adaptive significance of these morphological traits is discussed and it is suggested that A. sarsi and its congenerics are highly adapted necrophages. Onisimus littoralis, Orchomenella pinguis, and P. nobilis are thought to be scavenging omnivores. A parallel is drawn between the presumed ecological role of A. sarsi in circalittoral ecosystems and that of the genera Hirondellea and Eurythenes in the abyss.