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961.
Predictions of stream nutrient and sediment yield changes following restoration of forested riparian buffers 总被引:6,自引:1,他引:6
Stephanie M. Parkyn Robert J. Davies-Colley A. Bryce Cooper Morag J. Stroud 《Ecological Engineering》2005,24(5):551-558
Riparian tree planting is widely recognised as a means to improve water quality and stream habitat. However, shading of riparian pasture grasses can lead to channel widening, and riparian shade may limit the growth of macrophytes and algae that assimilate dissolved nutrients from the water column. We investigated concerns that riparian management could lead to increased yields of nutrients and sediments through a conceptual modelling exercise. A simple model of the trade-off between interception of nutrients in runoff by forest buffers versus reduction of in-stream uptake due to shade, predicted that a buffer strip alongside a small headwater stream would reduce nutrient export, while a buffer strip instigated as an isolated patch alongside a larger stream (c. >2.5 km2 upstream catchment size) would increase nutrient export, as the relative amount of nutrients trapped by the buffer decreases as the nutrient load present in the stream water increases. However, in these larger streams with width exceeding approximately 6 m, sufficient light may reach the streambed for plant and algal growth, which in turn would promote instream nutrient processing. At the peak of streambank erosion after planting, predicted total sediment yield (hillslope plus bank sources) was appreciably higher than the hillslope pasture yield, but sediment yield stabilised c. 35–40 years after planting. When planting was extended over 40 years in the model, the sediment yield never exceeded that in pasture before planting. This conceptual modelling exercise shows that riparian tree planting programmes should commence in the headwaters and progress downstream to avoid nutrient yield increases. Significant sediment yield from bank stored sediment of small streams can be expected until the channel reaches the more stable, original forested width, but progressive planting may decrease the peak loads of sediment. 相似文献
962.
Muthukumaran Sivanandham Palma Shaw Stephanie F. Bernik Enzo Paoletti Marc K. Wallack 《Cancer immunology, immunotherapy : CII》1998,46(5):261-267
A replication-deficient recombinant vaccinia virus, NYVAC, was developed by deleting 18 open reading frames in the vaccinia
virus genome. Recombinant NYVAC, encoding the murine T cell co-stimulatory gene B7.1 (CD 80) (NYVAC-B7.1) and the murine interleukin-2
gene (NYVAC-IL-2), were prepared and the expression of B7.1 and the secretion of IL-2 were respectively confirmed in vitro.
The use of these viruses to prepare a potent tumor cell vaccine was studied in a syngeneic murine CC-36 colon adenocarcinoma
model. Mice were immunized on days 1 and 8 with 106 irradiated CC-36 cells that were infected with 107 plaque-forming units of either NYVAC-B7.1, NYVAC-IL-2 or a control virus, NYVAC-HR, which encodes a vaccinia virus host-range
gene. These mice were then challenged with 108 viable CC-36 tumor cells on day 15. All mice (10/10) in a group that had received no vaccination and all mice (20/20) in
a group that had received a control vaccine of CC-36/NYVAC-HR developed tumor 4-weeks after tumor cell challenge. Interestingly,
only 16/20 mice in a group that had received CC-36/NYVAC-B7.1 showed the development of tumor after the same interval. The
protection against tumor development and the reduction in tumor burden (as mean tumor diameter, 4 weeks after tumor challenge)
were significant in this group when compared to groups that were either unvaccinated or vaccinated with CC-36/NYVAC-HR (mean
tumor diameter = 6.51±3.2 mm compared to 26.5±0.9 mm or 26.2±1.8 mm respectively) (P = < 0.05). The protection against tumor in a group of mice that received CC-36/NYVAC-IL-2 vaccination was similar to that
in the unvaccinated group or the group receiving a CC-36/NYVAC-HR control vaccination. However, in a survival experiment,
mice that received either CC36/NYVAC-B7.1 or CC-36/NYVAC-IL-2 vaccination on the day of tumor transplantation survived significantly
longer than mice that had not been vaccinated (median survival 60+ days, 60+ days or 23.5 days respectively) (P = <0.05). Interestingly, when a therapeutic tumor vaccination was performed on day 4 after tumor transplantation, mice that
had been vaccinated with either CC36/NYVAC-B7.1 or CC-36/NYVAC-IL-2 did not show an improved survival when compared to mice
in the control that had not been vaccinated (median survival 28 days compared to 26 days or 25 days respectively). However,
mice that had received a therapeutic vaccination with CC-36 cells infected with both NYVAC-B7.1 and NYVAC-IL-2, 4 days after
tumor transplantation, survived significantly longer than control mice that had not received any vaccination (median survival
29.5 days compared to 25 days respectively) (P<0.05). These results suggest that a replication-deficient recombinant NYVAC encoding the B7.1 gene and NYVAC encoding the
IL-2 gene can be used to produce an effective vaccinia-virus-augmented tumor cell vaccine.
Received: 2 March 1998 / Accepted 23 March 1998 相似文献
963.
M. Hixon Elise Millie L. A. Judis Stephanie Sherman Katherine Allran Lisa Taft Terry Hassold 《Human genetics》1998,103(6):654-657
Paternal nondisjunction accounts for approximately 5% of cases of trisomy 21. To test the hypothesis that, in some such cases,
the fathers might be predisposed to meiotic nondisjunction, we utilized fluorescence in situ hybridization (FISH) to screen
for aneuploidy in sperm. We analyzed sperm samples from ten males with a trisomy 21 offspring of paternal origin. Among these
individuals, the overall frequency of disomy 21 was 0.15%, comparable to estimates of disomy 21 in the general male population.
Furthermore, none of the ten fathers of trisomy 21 individuals had significantly elevated levels of disomic sperm. Thus, our
results provide no evidence that the occurrence of a trisomy 21 conceptus of paternal origin imparts an increased risk of
trisomy in subsequent pregnancies.
Received: 9 September 1998 / Accepted: 30 September 1998 相似文献
964.
Dong-chuan Guo Ellen S. Regalado Amelie Pinard Jiyuan Chen Kwanghyuk Lee Christina Rigelsky Lior Zilberberg Ellen M. Hostetler Micheala Aldred Stephanie E. Wallace Siddharth K. Prakash Suzanne M. Leal Michael J. Bamshad Deborah A. Nickerson Marvin Natowicz Daniel B. Rifkin Dianna M. Milewicz 《American journal of human genetics》2018,102(4):706-712
965.
966.
967.
Building strong relationships between conservation genetics and primary industry leads to mutually beneficial genomic advances
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Stephanie J. Galla Thomas R. Buckley Rob Elshire Marie L. Hale Michael Knapp John McCallum Roger Moraga Anna W. Santure Phillip Wilcox Tammy E. Steeves 《Molecular ecology》2016,25(21):5267-5281
Several reviews in the past decade have heralded the benefits of embracing high‐throughput sequencing technologies to inform conservation policy and the management of threatened species, but few have offered practical advice on how to expedite the transition from conservation genetics to conservation genomics. Here, we argue that an effective and efficient way to navigate this transition is to capitalize on emerging synergies between conservation genetics and primary industry (e.g., agriculture, fisheries, forestry and horticulture). Here, we demonstrate how building strong relationships between conservation geneticists and primary industry scientists is leading to mutually‐beneficial outcomes for both disciplines. Based on our collective experience as collaborative New Zealand‐based scientists, we also provide insight for forging these cross‐sector relationships. 相似文献
968.
Wiebke Garrels Ayan Mukherjee Stephanie Holler Nicole Cleve Thirumala R. Talluri Brigitte Barg-Kues Mike Diederich Peter Köhler Björn Petersen Andrea Lucas-Hahn Heiner Niemann Zsuzsanna Izsvák Zoltán Ivics Wilfried A. Kues 《Transgenic research》2016,25(1):63-70
Recently, we established the Sleeping Beauty transposon system for germ line competent transgenesis in the pig. Here, we extend this approach to re-target a transposon-tagged locus for a site-specific gene knock-in, and generated a syngeneic cohort of piglets carrying either the original transposon or the re-targeted event. A Cre-loxP-mediated cassette exchange of the tagging transposon with a different reporter gene was performed, followed by flow cytometric sorting and somatic cell nuclear transfer of recombined cells. In parallel, the original cells were employed in somatic cell nuclear transfer to generate clone siblings, thereby resulting in a clone cohort of piglets carrying different reporter transposons at an identical chromosomal location. Importantly, this strategy supersedes the need for an antibiotic selection marker. This approach expands the arsenal of genome engineering technologies in domestic animals, and will facilitate the development of large animal models for human diseases. Potentially, the syngeneic cohort of pigs will be instrumental for vital tracking of transplanted cells in pre-clinical assessments of novel cell therapies. 相似文献
969.
Maya L. Groner Luke A. Rogers Andrew W. Bateman Brendan M. Connors L. Neil Frazer Sean C. Godwin Martin Krko?ek Mark A. Lewis Stephanie J. Peacock Erin E. Rees Crawford W. Revie Ulrike E. Schl?gel 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2016,371(1689)
Effective disease management can benefit from mathematical models that identify drivers of epidemiological change and guide decision-making. This is well illustrated in the host–parasite system of sea lice and salmon, which has been modelled extensively due to the economic costs associated with sea louse infections on salmon farms and the conservation concerns associated with sea louse infections on wild salmon. Consequently, a rich modelling literature devoted to sea louse and salmon epidemiology has been developed. We provide a synthesis of the mathematical and statistical models that have been used to study the epidemiology of sea lice and salmon. These studies span both conceptual and tactical models to quantify the effects of infections on host populations and communities, describe and predict patterns of transmission and dispersal, and guide evidence-based management of wild and farmed salmon. As aquaculture production continues to increase, advances made in modelling sea louse and salmon epidemiology should inform the sustainable management of marine resources. 相似文献
970.