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101.

Increasing rates of Anthropocene biodiversity extinctions suggest a possible sixth mass extinction event. Conservation planners are seeking effective ways to protect species, hotspots of biodiversity, and dynamic ecosystems to reduce and eventually eliminate the degradation and loss of diversity at the scale of genes, species, and ecosystems. While well-established, adequately enforced protected areas (PAs) increase the likelihood of preserving species and habitats, traditional placement methods are frequently inadequate in protecting biodiversity most at risk. Consequently, the Key Biodiversity Area (KBA) Partnership developed a set of science-based criteria and thresholds that iteratively identify sites where biodiversity is most in need of protection. KBA methodology has been rarely applied in the marine realm, where data are often extremely limited. We tested the feasibility of KBA population metrics in the Greater Caribbean marine region using occurrence and population data and threat statuses for 1669 marine vertebrates. These data identified areas where site-specific conservation measures can effectively protect biodiversity. Using KBA criteria pertaining to threatened and irreplaceable biodiversity, we identified 90 geographically unique potential KBAs, 34 outside and 56 within existing PAs. These provide starting points for local conservation managers to verify that KBA thresholds are met and to delineate site boundaries. Significant data gaps, such as population sizes, life history characteristics, and extent of habitats, prevent the full application of the KBA criteria to data-poor marine species. Increasing the rate and scope of marine sampling programs and digital availability of occurrence datasets will improve identification and delineation of KBAs in the marine environment.

  相似文献   
102.
Sequence similarity was used to predict the position of expressed sequence tags (ESTs) in the genome of the turkey (Meleagris gallopavo). Turkey EST sequences were compared with the draft assembly of the chicken whole-genome sequence and the chicken EST database by BLASTN. Among the 877 ESTs examined, 788 had significant matches in the chicken genome sequence. Position of orthologous sequences in the chicken genome and the predicted position of the EST loci in the turkey genome are presented. Genetic assignments suggest a high level of accuracy for the COMPASS predictions.  相似文献   
103.
N-Acylethanolamines (NAEs) are fatty-acid derivatives with potent biological activities in a wide range of eukaryotic organisms. Polyunsaturated NAEs are among the most abundant NAE types in seeds of Arabidopsis thaliana, and they can be metabolized by either fatty acid amide hydrolase (FAAH) or by lipoxygenase (LOX) to low levels during seedling establishment. Here, we identify and quantify endogenous oxylipin metabolites of N-linolenoylethanolamine (NAE 18:3) in Arabidopsis seedlings and show that their levels were higher in faah knockout seedlings. Quantification of oxylipin metabolites in lox mutants demonstrated altered partitioning of NAE 18:3 into 9- or 13-LOX pathways, and this was especially exaggerated when exogenous NAE was added to seedlings. When maintained at micromolar concentrations, NAE 18:3 specifically induced cotyledon bleaching of light-grown seedlings within a restricted stage of development. Comprehensive oxylipin profiling together with genetic and pharmacological interference with LOX activity suggested that both 9-hydroxy and 13-hydroxy linolenoylethanolamides, but not corresponding free fatty-acid metabolites, contributed to the reversible disruption of thylakoid membranes in chloroplasts of seedling cotyledons. We suggest that NAE oxylipins of linolenic acid represent a newly identified, endogenous set of bioactive compounds that may act in opposition to progression of normal seedling development and must be depleted for successful establishment.  相似文献   
104.
Abstract

Novel solid supports and CE-phosphoramidite reagents have been prepared featuring a unique 2′-deoxyribosyl backbone. These chirally pure reagents form the basis of an oligonucleotide labeling system which provides diastereomerically pure oligonucleotides.  相似文献   
105.
Assembly of the Escherichia coli 30S ribosomal subunits proceeds through multiple parallel pathways. The protein factors RimM, YjeQ, RbfA, and Era work in conjunction to assist at the late stages of the maturation process of the small subunit. However, it is unclear how the functional interplay between these factors occurs in the context of multiple parallel pathways. To understand how these factors work together, we have characterized the immature 30S subunits that accumulate in ΔrimM cells and compared them with immature 30S subunits from a ΔyjeQ strain. The cryo-EM maps obtained from these particles showed that the densities representing helices 44 and 45 in the rRNA were partially missing, suggesting mobility of these motifs. These 30S subunits were also partially depleted in all tertiary ribosomal proteins, particularly those binding in the head domain. Using image classification, we identified four subpopulations of ΔrimM immature 30S subunits differing in the amount of missing density for helices 44 and 45, as well as the amount of density existing in these maps for the underrepresented proteins. The structural defects found in these immature subunits resembled those of the 30S subunits that accumulate in the ΔyjeQ strain. These findings are consistent with an “early convergency model” in which multiple parallel assembly pathways of the 30S subunit converge into a late assembly intermediate, as opposed to the mature state. Functionally related factors will bind to this intermediate to catalyze the last steps of maturation leading to the mature 30S subunit.  相似文献   
106.
107.
Small RNA cloning and sequencing is uniquely positioned as a genome-wide approach to quantify miRNAs with single-nucleotide resolution. However, significant biases introduced by RNA ligation in current protocols lead to inaccurate miRNA quantification by 1000-fold. Here we report an RNA cloning method that achieves over 95% efficiency for both 5′ and 3′ ligations. It achieves accurate quantification of synthetic miRNAs with less than two-fold deviation from the anticipated value and over a dynamic range of four orders of magnitude. Taken together, this high-efficiency RNA cloning method permits accurate genome-wide miRNA profiling from total RNAs.  相似文献   
108.
109.
In Drosophila, the secreted signaling molecule Jelly Belly (Jeb) activates anaplastic lymphoma kinase (Alk), a receptor tyrosine kinase, in multiple developmental and adult contexts. We have shown previously that Jeb and Alk are highly enriched at Drosophila synapses within the CNS neuropil and neuromuscular junction (NMJ) and postulated a conserved intercellular signaling function. At the embryonic and larval NMJ, Jeb is localized in the motor neuron presynaptic terminal whereas Alk is concentrated in the muscle postsynaptic domain surrounding boutons, consistent with anterograde trans‐synaptic signaling. Here, we show that neurotransmission is regulated by Jeb secretion by functional inhibition of Jeb–Alk signaling. Jeb is a novel negative regulator of neuromuscular transmission. Reduction or inhibition of Alk function results in enhanced synaptic transmission. Activation of Alk conversely inhibits synaptic transmission. Restoration of wild‐type postsynaptic Alk expression in Alk partial loss‐of‐function mutants rescues NMJ transmission phenotypes and confirms that postsynaptic Alk regulates NMJ transmission. The effects of impaired Alk signaling on neurotransmission are observed in the absence of associated changes in NMJ structure. Complete removal of Jeb in motor neurons, however, disrupts both presynaptic bouton architecture and postsynaptic differentiation. Nonphysiologic activation of Alk signaling also negatively regulates NMJ growth. Activation of Jeb–Alk signaling triggers the Ras‐MAP kinase cascade in both pre‐ and postsynaptic compartments. These novel roles for Jeb–Alk signaling in the modulation of synaptic function and structure have potential implications for recently reported Alk functions in human addiction, retention of spatial memory, cognitive dysfunction in neurofibromatosis, and pathogenesis of amyotrophic lateral sclerosis. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013  相似文献   
110.

Introduction

This cluster randomised trial evaluated an intervention to decrease x-ray referrals and increase giving advice to stay active for people with acute low back pain (LBP) in general practice.

Methods

General practices were randomised to either access to a guideline for acute LBP (control) or facilitated interactive workshops (intervention). We measured behavioural predictors (e.g. knowledge, attitudes and intentions) and fear avoidance beliefs. We were unable to recruit sufficient patients to measure our original primary outcomes so we introduced other outcomes measured at the general practitioner (GP) level: behavioural simulation (clinical decision about vignettes) and rates of x-ray and CT-scan (medical administrative data). All those not involved in the delivery of the intervention were blinded to allocation.

Results

47 practices (53 GPs) were randomised to the control and 45 practices (59 GPs) to the intervention. The number of GPs available for analysis at 12 months varied by outcome due to missing confounder information; a minimum of 38 GPs were available from the intervention group, and a minimum of 40 GPs from the control group. For the behavioural constructs, although effect estimates were small, the intervention group GPs had greater intention of practising consistent with the guideline for the clinical behaviour of x-ray referral. For behavioural simulation, intervention group GPs were more likely to adhere to guideline recommendations about x-ray (OR 1.76, 95%CI 1.01, 3.05) and more likely to give advice to stay active (OR 4.49, 95%CI 1.90 to 10.60). Imaging referral was not statistically significantly different between groups and the potential importance of effects was unclear; rate ratio 0.87 (95%CI 0.68, 1.10) for x-ray or CT-scan.

Conclusions

The intervention led to small changes in GP intention to practice in a manner that is consistent with an evidence-based guideline, but it did not result in statistically significant changes in actual behaviour.

Trial Registration

Australian New Zealand Clinical Trials Registry ACTRN012606000098538  相似文献   
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