Search Results - (Author, Cooperation:M. W. Davis)

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  1. 1
    Latest Papers from Table of Contents or Articles in Press
  2. 2
    S. Watanabe ; B. R. Rost ; M. Camacho-Perez ; M. W. Davis ; B. Sohl-Kielczynski ; C. Rosenmund ; E. M. Jorgensen
    Nature Publishing Group (NPG)
    Published 2013
    Staff View
    Publication Date:
    2013-12-07
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Actins/metabolism/ultrastructure ; Action Potentials ; Animals ; Dynamins/metabolism/ultrastructure ; *Endocytosis ; Exocytosis ; Hippocampus/*cytology ; Membrane Fusion ; Mice ; Microscopy, Electron ; Rhodopsin/genetics/metabolism ; Synapses/*metabolism/ultrastructure ; Synaptic Transmission ; Synaptic Vesicles/metabolism/ultrastructure ; Time Factors
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  3. 3
    Staff View
    Publication Date:
    2014-10-09
    Publisher:
    Nature Publishing Group (NPG)
    Print ISSN:
    0028-0836
    Electronic ISSN:
    1476-4687
    Topics:
    Biology
    Chemistry and Pharmacology
    Medicine
    Natural Sciences in General
    Physics
    Keywords:
    Animals ; Cell Membrane/metabolism ; Clathrin/*metabolism ; Endocytosis ; Endosomes/*metabolism ; Humans ; Mice ; Synaptic Vesicles/*metabolism ; Temperature
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  4. 4
    Afema, J. A., Ahmed, S., Besser, T. E., Jones, L. P., Sischo, W. M., Davis, M. A.
    The American Society for Microbiology (ASM)
    Published 2018
    Staff View
    Publication Date:
    2018-03-06
    Publisher:
    The American Society for Microbiology (ASM)
    Print ISSN:
    0099-2240
    Electronic ISSN:
    1098-5336
    Topics:
    Biology
    Published by:
    Latest Papers from Table of Contents or Articles in Press
  5. 5
    Olla, B L ; Davis, M W ; Schreck, C B

    Oxford, UK : Blackwell Publishing Ltd
    Published 1995
    Staff View
    ISSN:
    1365-2109
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes:
    This study examined whether rapid recovery from stress-induced impairment in predator evasion, observed in previous studies on coho salmon, Oncorhynchus kisutch (Walbaum), was a general characteristic of different stocks of the same species and different species of Pacific salmon. We monitored stress-induced non-predator mortality, predator evasion and Cortisol concentrations of smolts of coho and spring Chinook, O. tshawytscha (Walbaum), after administration of standardized single and multiple handling stresses. Marked differences in the response to handling stress among stocks of coho and spring chinook smolts were evident, with recovery from impaired predator evasion occurring within 24 h of a 30-s handling stress for coho smolts and 24 h of a 1-min handling stress for spring chinook smolts. Differences in stress-induced non-predator mortality among stocks were also observed. The results point to the importance of screening hatchery salmonid stocks to assess differing capabilities of dealing with stress.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  6. 6
    Løkkeborg, S. ; Olla, B. L. ; Pearson, W. H. ; Davis, M. W.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1995
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    A behavioural bioassay was used to determine the response threshold to squid extract of sablefish, Anoplopoma fimbria, held at three different feeding regimens. Sablefish responded to the odour of bait by changing swimming activity and turning behaviour. The response threshold to bait odour was influenced by both the amount of food eaten and the duration of food deprivation. The total concentration of amino acids in the bait extract was assumed to determine the response threshold as chemical fractionation studies have shown that this class of compounds is essential for the stimulatory capacities of food extracts. When fed to satiation (9.4% wet body weight) and tested after one day of food deprivation, the mean response threshold to total dissolved free amino acids was 4.4 × 10−8m (range=7.6 × 10−8 to 3.6 × 10−8m). When fed at 1.6-2.3% wet body weight, the threshold sensitivity had increased to a mean value of 1.8 × 10−10m (range=8.4 × 10−10 to 7.0 × 10−11m) after one day of food deprivation; after four days of deprivation, the sensitivity had increased even further to a mean value of 1.4 × 10−11m (range=1.6 × 10−10 to 1.4 × 10−12m). It was also apparent that the intensity of behavioural responses to the bait odour increased with both stimulus concentration and duration of food deprivation. These results suggest that sablefish intensify their search for prey under increased feeding motivation. The active space of a bait source was estimated from the threshold values obtained. Depending on state of food deprivation, rate of chemical release from the bait and the current velocity, maximum lengths of active space within which sablefish would exhibit food searching responses vary from 10 m to several km. Stock assessment based on catch data from baited gear will need techniques that take into account those factors influencing active space for food searching.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  7. 7
    Olla, B. L. ; Davis, M. W.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1993
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    Changes in buoyancy in fertilized bathypelagic eggs of the walleye pollock, Theragra chalcogramma, collected from Shelikof Strait in the Gulf of Alaska were measured under controlled laboratory conditions in density gradient columns from 90 h post–fertilization through hatching. Eggs were incubated at 6° C and exposed to either diel light or constant dark. Eggs held under diel light conditions became more dense than eggs under constant dark beginning 〈10 h after exposure to light and remained so until 12 h before hatching. Eggs held under constant dark then became more dense than those under diel light. Hatching of eggs under both conditions began at the same time but eggs under diel light showed a delayed hatching rate. Light–induced changes in egg density indicate the ability of walleye pollock eggs to respond to external stimuli and thereby alter their position in the water column in an ecologically meaningful way.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  8. 8
    OLLA, B. L. ; Davis, M. W. ; Schreck, C. B.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1998
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    For sablefish Anoplopoma fimbria that had been transferred abruptly from ambient (5·7° C) to temperatures ranging from 15 to 20° C for 30 min followed by 15 min in air (19·5) C), mortality increased with temperature. Mortality occurred at lower temperatures for sablefish that were net-towed for 4 h at ambient temperature before exposure to a rapid increase in temperature. A clear relationship was apparent between serum lactate and temperature with lactate increasing as temperature increased. For treatments in which mortality did not occur, lactate decreased sharply within 24 h, suggesting recovery. It would appear that the critical postcapture temperature for sablefish that reside and are captured at 4-6° C, would be between 12 and 15° C. The results of this study suggest that fishery management strategies designed to increase postcapture survival of sablefish bycatch should include a consideration of the impact of exposure to seasonal thermoclines and seasonally elevated air temperatures.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  9. 9
    Davis, M. W.

    Oxford, UK; Malden, USA : Blackwell Publishing Ltd/Inc.
    Published 2005
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    Sablefish Anoplopoma fimbria aged 1+ and 2+ years were towed for 4 h in a net, transferred to air for either 15 or 30 min, and then held in tanks for up to 35 days for observation of physical injury, immediate mortality, behaviour impairment, delayed mortality and total mortality. Behaviour was impaired for at least 3 h and returned to normal levels by 24 h after stress induction. Behaviour impairment was correlated with delayed mortality in 2+ year fish but not in 1+ year fish which showed greater variation in stress responses. The results of this study and a review of past discard and escapee studies showed that substitute measures for delayed mortality in the field should include physical injury and behaviour impairment. These two measures integrate the effects of capture-related stressors which can produce and magnify physical and physiological injury, resulting in changes in fish condition and delayed mortality.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  10. 10
    Davis, M. W. ; Olla, B. L. ; Schreck, C. B.

    Oxford, UK : Blackwell Publishing Ltd
    Published 2001
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    In a series of laboratory studies designed to simulate bycatch processes, sablefish Anoplopoma fimbria were either hooked for up to 24 h or towed in a net for 4 h and then subjected to an abrupt transfer to elevated sea water temperature and air. Mortality did not result from hooking or net towing followed by exposure to air, but increased for both capture methods as fish were exposed to elevated temperatures, reflecting the magnifying effect of elevated temperature on mortality. Hooking and exposure to air resulted in increased plasma cortisol and lactate concentrations, while the combination of hooking and exposure to elevated temperature and air resulted in increased lactate and potassium oncentrations. In fish that were towed in a net and exposed to air, cortisol, lactate, potassium and sodium concentrations increased, but when subjected to elevated temperature and air, no further increases occurred above the concentrations induced by net towing and air, suggesting a possible maximum of the physiological stress response. The results suggest that caution should be exercised when using physiological measures to quantify stress induced by capture and exposure to elevated temperature and air, that ultimately result in mortality, since the connections between physiological stress and mortality in bycatch processes remain to be fully understood.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  11. 11
    Olla, B. L. ; Davis, M. W. ; Schreck, C. B.

    Oxford, UK : Blackwell Publishing Ltd
    Published 1997
    Staff View
    ISSN:
    1095-8649
    Source:
    Blackwell Publishing Journal Backfiles 1879-2005
    Topics:
    Biology
    Notes:
    Laboratory apparatus which simulated capture of fish in the cod-end of a towed trawl was used to induce post-capture stress as measured by alterations in behavioural, physiological and mortality indices in juvenile walleye pollock Theragra chalcogramma and juvenile and adult sablefish Anoplopoma fimbria. Differences in resistance to net entrainment varied between species with the severity of stress and the potential for recovery depending on light intensity, net velocity and towing duration. At a light intensity which simulated daylight at depth in clear ocean water (0.5 μmol photons m−2 s−1), walleye pollock juveniles were able to maintain swimming in nets towed at 0.65 m s−1 for 3h with no discernible effects on behaviour or mortality. However, when net velocity was increased to 〉0.75m s−1 or light intensity was decreased to 〈0.002 μmol photons m−2 s−1, fish became entrained in the meshes of the net and exhibited significant alterations in feeding behaviour, predator evasion and increases in plasma cortisol concentrations. Marked increases in stress-induced mortality also occurred, in some cases after a delay of 6 days and eventually reaching 100%. In comparison with walleye pollock, sablefish juveniles became entrained in the meshes of the net at higher velocities (〉0.92m s−1) or lower light intensities (〈0.0004 μmol photons m−2 s−1) and were much more resistant to post-capture stress. Towing of net-entrained fish for 15 min caused no detectable changes in feeding and cortisol and for 2 h, no changes in feeding although mortality increased from 0% for 15-min tows to 19% for 2-h tows. Towing for 4 h caused significant alterations in feeding and cortisol with feeding recovering to control levels by 6 days and cortisol by 3 days; mortality was 25%. When adult sablefish were towed for 4 h followed by 15-min exposure to air, feeding was inhibited 6 days after towing, but recovered within 30 days with no mortality observed after 30 days. The results demonstrate the value of using laboratory-based behavioural and biochemical indices to identify factors that may potentially affect post-capture survival among different species of fish.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses
  12. 12
    Staff View
    ISSN:
    1432-0967
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Geosciences
    Notes:
    Abstract This investigation describes five Mesozoic dolerite dikes which intrude Paleozoic metamorphic and igneous rocks of the Inner Piedmont of western South Carolina. The dikes are vertical or nearly so and strike approximately N40° W. Three major northeast-trending faults also occur in the study area. Left lateral displacement of one dolerite is documented at a locality near Cleveland, South Carolina. Elsewhere, several of the dolerite dikes appear to terminate at or near the faults. — The dolerite dikes have subophitic to microporphyritic textures and consist principally of plagioclase (generally An70–80), olivine (dominantly Fo80–90) and augite with subordinate pigeonite, titanomagnetite, chromite and brown, partly glassy mesostasis. In one dike pyroxene compositions trend from augite to ferroaugite in contrast to an augite→subcalcic augite→pigeonite trend characteristic of the other dolerites. The contrasting trends primarily result from differences in SiO2 abundance in the dolerite magmas. — Major and trace element analyses indicate the presence of two different olivine-normative dolerite magma types. The two magma types are not related by near surface crystal fractionation. Models for genesis of the olivine-normative dolerite magmas by partial melting of a plagioclase peridotite upper mantle source region are presented. The models require that the source region be enriched in LREE and incompatible elements such as Rb, Ba, Hf and Th relative to Cl chondritic abundances. One magma type appears to represent a primary dolerite magma that ascended from the source region with little subsequent compositional change. The second magma type most likely experienced assimilation of clinopyroxene-garnet (eclogite) during ascent, thereby acquiring a REE pattern with a less steep negative slope for the LREE and a slight positive slope in the HREE.
    Type of Medium:
    Electronic Resource
    URL:
    Articles: DFG German National Licenses