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排序方式: 共有196条查询结果,搜索用时 31 毫秒
101.
Andrea T. Kramer Barbara Crane Jeff Downing J.L. Hamrick Kayri Havens Amy Highland Sarah K. Jacobi Thomas N. Kaye Eric V. Lonsdorf Jennifer Ramp Neale Ari Novy Peter E. Smouse Douglas W. Tallamy Abigail White Jacob Zeldin 《Restoration Ecology》2019,27(3):470-476
Current guidance on sourcing native plants to support ecosystem function focuses on the high risk of failure when unsuitable material is used in ecological restoration. However, there is growing recognition that risks may be lower and rewards higher at highly disturbed sites isolated from remnant populations, especially when considering support for pollinators, wildlife, and other ecosystem functions. We developed the first decision support tool using expert opinion to assess suitability of different native plant sources, including horticultural cultivars, in two different planting contexts. We assessed the suitability of 761 sources for 72 commonly sold native species in two different planting contexts (small, isolated, highly disturbed sites vs. large, undisturbed sites near remnant populations). Information on genetic and adaptive backgrounds of sources was strikingly lacking, forcing us to exclude one‐third of sources from our assessment. While only 3% of cultivars received high suitability scores for use in large, undisturbed sites near remnant populations, 52% received high suitability scores in small, isolated, highly disturbed sites. However, nearly 25% of cultivars had floral or leaf traits that differed from wild plants in ways that may compromise their ability to support pollinators and other wildlife. Forbs and cultivars lacking genetic diversity and source information were most likely to have altered traits. We recommend that native plant breeders and sellers work together to ensure ecosystem function, adaptation, and diversity information is available to consumers, that consumers request this information to drive demand, and that researchers further investigate how context influences risks and benefits of different sources. 相似文献
102.
Developing and Communicating a Taxonomy of Ecological Indicators: A Case Study from the Mid-Atlantic
Denice Heller Wardrop Carl Hershner Kirk Havens Kent Thornton Donna Marie Bilkovic 《EcoHealth》2007,4(2):179-186
To ensure indicators of ecosystem health are integrated into environmental decision-making, it is imperative to provide a
comprehensive framework for indicator selection and use. The same framework can also be used to evaluate the utility of any
given indicator. The Atlantic Slope Consortium (ASC) has developed such a framework, based upon three primary elements: 1)
The specific questions to be answered (the type of indicator), recognizing the following types of questions/indicators: Condition assessment: snapshot of the current state of the system; Stressor diagnosis: identification of causative factors of condition; Communication to the public: encouraging comprehension of condition in its most elementary or integrated form; Futures assessment: estimating the probable trajectory of condition, or assessing the vulnerability of any system to a stochastic event; Evaluation: a subset of condition indicators that evaluate the effectiveness of management actions. 2) The spatial and/or temporal scale
of the issue being addressed (the spatial/temporal scale over which the indicator is valid). 3) The context of the question,
using categories of surrounding land use as surrogates for social choices. A Fish Community Index (FCI) developed for the
ASC will provide an example of utilizing the framework to select an indicator, as well as using the framework to judge the
utility of the indicator. 相似文献
103.
Gómez-Blanco J Luque D González JM Carrascosa JL Alfonso C Trus B Havens WM Ghabrial SA Castón JR 《Journal of virology》2012,86(15):8314-8318
Cryoelectron microscopy reconstruction of Cryphonectria nitschkei virus 1, a double-stranded RNA (dsRNA) virus, shows that the capsid protein (60 copies/particle) is formed by a repeated helical core, indicative of gene duplication. This unusual organization is common to chrysoviruses. The arrangement of many of these putative α-helices is conserved in the totivirus L-A capsid protein, suggesting a shared motif. Our results indicate that a 120-subunit T=1 capsid is a conserved architecture that optimizes dsRNA replication and organization. 相似文献
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105.
Megan Ulmer Carnes Yangfan P. Liu R. Rand Allingham Benjamin T. Whigham Shane Havens Melanie E. Garrett Chunyan Qiao NEIGHBORHOOD Consortium Investigators Nicholas Katsanis Janey L. Wiggs Louis R. Pasquale Allison Ashley-Koch Edwin C. Oh Michael A. Hauser 《PLoS genetics》2014,10(5)
Glaucoma is a leading cause of blindness worldwide. Primary open-angle glaucoma (POAG) is the most common subtype and is a complex trait with multigenic inheritance. Genome-wide association studies have previously identified a significant association between POAG and the SIX6 locus (rs10483727, odds ratio (OR) = 1.32, p = 3.87×10−11). SIX6 plays a role in ocular development and has been associated with the morphology of the optic nerve. We sequenced the SIX6 coding and regulatory regions in 262 POAG cases and 256 controls and identified six nonsynonymous coding variants, including five rare and one common variant, Asn141His (rs33912345), which was associated significantly with POAG (OR = 1.27, p = 4.2×10−10) in the NEIGHBOR/GLAUGEN datasets. These variants were tested in an in vivo Danio rerio (zebrafish) complementation assay to evaluate ocular metrics such as eye size and optic nerve structure. Five variants, found primarily in POAG cases, were hypomorphic or null, while the sixth variant, found only in controls, was benign. One variant in the SIX6 enhancer increased expression of SIX6 and disrupted its regulation. Finally, to our knowledge for the first time, we have identified a clinical feature in POAG patients that appears to be dependent upon SIX6 genotype: patients who are homozygous for the SIX6 risk allele (His141) have a statistically thinner retinal nerve fiber layer than patients homozygous for the SIX6 non-risk allele (Asn141). Our results, in combination with previous SIX6 work, lead us to hypothesize that SIX6 risk variants disrupt the development of the neural retina, leading to a reduced number of retinal ganglion cells, thereby increasing the risk of glaucoma-associated vision loss. 相似文献
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108.
Slk19p is a member of the Cdc-14 early anaphase release (FEAR) pathway, a signaling network that is responsible for activation of the cell-cycle regulator Cdc14p in Saccharomyces cerevisiae. Disruption of the FEAR pathway results in defects in anaphase, including alterations in the assembly and behavior of the anaphase spindle. Many phenotypes of slk19Δ mutants are consistent with a loss of FEAR signaling, but other phenotypes suggest that Slk19p may have FEAR-independent roles in modulating the behavior of microtubules in anaphase. Here, a series of SLK19 in-frame deletion mutations were used to test whether Slk19p has distinct roles in anaphase that can be ascribed to specific regions of the protein. Separation-of-function alleles were identified that are defective for either FEAR signaling or aspects of anaphase spindle function. The data suggest that in early anaphase one region of Slk19p is essential for FEAR signaling, while later in anaphase another region is critical for maintaining the coordination between spindle elongation and the growth of interpolar microtubules. 相似文献
109.
110.
Havens BA Velonis D Kronenberg MS Lichtler AC Oliver B Mina M 《Developmental biology》2008,316(2):336-349
To address the functions of FGFR2 and FGFR3 signaling during mandibular skeletogenesis, we over-expressed in the developing chick mandible, replication-competent retroviruses carrying truncated FGFR2c or FGFR3c that function as dominant negative receptors (RCAS-dnFGFR2 and RCAS-dnFGFR3). Injection of RCAS-dnFGFR3 between HH15 and 20 led to reduced proliferation, increased apoptosis, and decreased differentiation of chondroblasts in Meckel's cartilage. These changes resulted in the formation of a hypoplastic mandibular process and truncated Meckel's cartilage. This treatment also affected the proliferation and survival of osteoprogenitor cells in osteogenic condensations, leading to the absence of five mandibular bones on the injected side. Injection of RCAS-dnFGFR2 between HH15 and 20 or RCAS-dnFGFR3 at HH26 did not affect the morphogenesis of Meckel's cartilage but resulted in truncations of the mandibular bones. RCAS-dnFGFR3 affected the proliferation and survival of the cells within the periosteum and osteoblasts. Together these results demonstrate that FGFR3 signaling is required for the elongation of Meckel's cartilage and FGFR2 and FGFR3 have roles during intramembranous ossification of mandibular bones. 相似文献