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31.
T. K. McCarthy P. Frankiewicz P. Cullen M. Blaszkowski W. O’Connor D. Doherty 《Hydrobiologia》2008,609(1):109-124
The Shannon, Ireland’s largest river, is used for hydroelectricity generation since 1929. Subsequently, the Electricity Supply
Board assumed responsibility for management of its eel stocks, due to the impact of the hydro-dam on recruitment to the commercial
fishery. In order to negate a decline in juvenile recruitment resulting from the installation of hydroelectric facilities,
management was focused on stocking lakes with elvers and fingerling eels. These were trapped at the hydropower facilities
and in estuarine tributaries during their up-stream migrations. Due to the decline of natural recruitment in more recent times,
attempts have also been made to develop an estuarine glass eel fishery. Stock levels are then monitored through annual surveys
of the population trends of juvenile (glass eel, elver), growing phase (yellow eel) and downstream migrating pre-spawners
(silver eels). Survey results and fishery management programmes are reviewed in this article. In addition to the long-term
effects the hydroelectric facilities have had on the stock levels, there is also an annual effect on the migratory patterns
of downstream migratory silver eels. In the lower reaches of the river system flow rates are regulated by the hydroelectric
stations. We review previous work that had highlighted the importance of flow in determining the timing of the silver eels
migrations, and assess the relationship between flow and migration in more detail through the use of hydroacoustic and telemetric
studies. Current research on seaward migrating silver eel populations, suggests that spawner escapement rates can most effectively
be increased by trapping migrating eels at fishing weirs located up-stream of the power station and transporting them towards
the estuary.
Guest editors: R. L. Welcomme & G. Marmulla
Hydropower, Flood Control and Water Abstraction: Implications for Fish and Fisheries 相似文献
32.
B.?McCarthy A.?Daws D.?L.?MacmillanEmail author 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2004,190(4):291-299
Recordings were made from the nerve innervating the stretch receptors of the abdominal muscle receptor organs and slow extensor muscles of tethered crayfish, Cherax destructor, during so-called non-giant swimming. The stretch receptors were active during the flexor phase of swimming but the duration and pattern of activity varied from cycle to cycle. Their pattern of firing was modified by the activity of the large accessory neurons which make direct inhibitory synapses upon them. Neither the stretch receptors nor the accessory neurons were active during the extensor phase of the cycle. The timing and extent of tailfan movements during the period of stretch receptor activity were measured from video records before and after the stretch receptor nerves were cut in the second to fifth segments. The promotion of the tailfan during flexion was significantly delayed and the minimum angle to which the uropods were remoted at the end of flexion significantly larger in denervated animals. We propose that afferent information from the stretch receptors coordinates the timing and extent of tailfan movements according to variations in the positioning and movement of the abdominal segments such that the hydrodynamic efficiency of the tailfan is enhanced on a cycle by cycle basis during non-giant swimming.Abbreviations A# abdominal segment number - Acc accessory neuron - LUU large unidentified unit - MRO muscle receptor organ - NGS non-giant swimming - SEMN slow extensor motor neuron - SR stretch receptor neuron 相似文献
33.
Effects of roads and land use on frog distributions across spatial scales and regions in the Eastern and Central United States 下载免费PDF全文
David M. Marsh Bradley J. Cosentino Kara S. Jones Joseph J. Apodaca Karen H. Beard Jane Margaret Bell Christine Bozarth Derrick Carper Julie F. Charbonnier Andreia Dantas Elizabeth A. Forys Miran Foster Jaquelyn General Kristen S. Genet Macie Hanneken Kyle R. Hess Shane A. Hill Faisal Iqbal Nancy E. Karraker Eran S. Kilpatrick Tom A. Langen James Langford Kathryn Lauer Alison J. McCarthy Joseph Neale Saumya Patel Austin Patton Cherie Southwick Nathaniel Stearrett Nicholas Steijn Mohammad Tasleem Joseph M. Taylor James R. Vonesh 《Diversity & distributions》2017,23(2):158-170
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Zhu YF Wang XC Connors P Wilcoxen K Gao Y Gross R Strack N Gross T McCarthy JR Xie Q Ling N Chen C 《Bioorganic & medicinal chemistry letters》2003,13(11):1931-1934
4-benzylquinolines 5, based on a series of isoquinolines 1, were prepared and tested as inhibitors of the IGF/IGFBP-3 complex based on their ability to displace IGF-I from its binding to IGF-binding protein-3. SAR studies on the 6,7-dihydroxy moiety of the quinoline 5a showed that the catecol moiety could be replaced with other functional groups. Computational modeling of the 5a/mini-IGFBP-5 complex revealed the possible binding site of 5a on IGFBP-5. 相似文献
39.
Wolfram M. Brück John K. Reed Peter J. McCarthy 《Marine biotechnology (New York, N.Y.)》2012,14(6):762-773
The marine lithistid sponge Discodermia spp. (Family Theonellidae) contains many types of associated bacteria visible in the mesohyl while biofilms cover the pinacoderm. This study determined the identity of bacteria associated with members of the genus Discodermia using microbial culture, 16S rRNA gene clone libraries and fluorescence in situ hybridization. Four samples of Discodermia spp. were collected at depths between 24–161?m near Grand Bahama Island and Cay Sal Bank, Bahamas. A total of 80 unique isolates and 94 different clone sequences from at least eight bacterial classes were obtained. It appeared that Discodermia spp. may have a core community of bacteria that is common to all sponges of this genus. Species of at least six different classes of bacteria were regularly found in most of the sponge specimens collected, irrespective of collection depth or location. This indicates that a diverse spectrum of bacteria is associated with lithistid sponges irrespective of the transient seawater community that enters the sponge. 相似文献
40.
William Hancock-Cerutti Zheng Wu Peng Xu Narayana Yadavalli Marianna Leonzino Arun Kumar Tharkeshwar Shawn M. Ferguson Gerald S. Shadel Pietro De Camilli 《The Journal of cell biology》2022,221(7)
Mutations in VPS13C cause early-onset, autosomal recessive Parkinson’s disease (PD). We have established that VPS13C encodes a lipid transfer protein localized to contact sites between the ER and late endosomes/lysosomes. In the current study, we demonstrate that depleting VPS13C in HeLa cells causes an accumulation of lysosomes with an altered lipid profile, including an accumulation of di-22:6-BMP, a biomarker of the PD-associated leucine-rich repeat kinase 2 (LRRK2) G2019S mutation. In addition, the DNA-sensing cGAS-STING pathway, which was recently implicated in PD pathogenesis, is activated in these cells. This activation results from a combination of elevated mitochondrial DNA in the cytosol and a defect in the degradation of activated STING, a lysosome-dependent process. These results suggest a link between ER-lysosome lipid transfer and innate immune activation in a model human cell line and place VPS13C in pathways relevant to PD pathogenesis. 相似文献