822 research outputs found
New Cryogenian, Neoproterozoic, and middle Paleozoic UāPb zircon ages from the Caledonia terrane, southern New Brunswick, Canada: better constrained but more complex volcanic stratigraphy
New UāPb zircon ages from volcanic, plutonic, and sedimentary units in the Avalonian Caledonia terrane of southern New Brunswick provide better timing constraints in this geologically complex area. Previous ca. 620 Ma ages from the Broad River Group are now corroborated by additional dates from felsic tuff in the Gordon Falls Formation and rhyolite in the former Fairfield (now East Branch Black River) Formation of 620 Ā± 5 Ma and 622 Ā± 1.9 Ma, respectively. Combined with ages ranging from ca. 625 Ma to 615 Ma from crosscutting plutons, the data suggest that the minimum age of the Broad River Group is about 615 Ma. A quartzfeldspar porphyry dyke in mafic volcanic rocks of the previously undated Long Beach Formation yielded an igneous crystallization age of 685 Ā± 10 Ma, the oldest unit yet dated in the Caledonia terrane but similar in age to porphyry in the Stirling belt in the Avalonian Mira terrane of Nova Scotia. The age of the Coldbrook Group was constrained previously by UāPb (zircon) ages of volcanic rocks between 560 and 550 Ma as well as by similar ages from comagmatic plutons. Five additional samples from both volcanic and plutonic units lie in the same range of 560ā550 Ma, including errors, demonstrating that the Coldbrook Group and related plutons formed in less than 10 million years. Such a large volume of mainly felsic magma erupted and emplaced in a short time span suggests a āsupereruption/supervolcanoā environment such as the late Cenozoic southwestern USA but not yet recognized at ca. 560ā550 Ma elsewhere in Avalonia. Two units yielded Paleozoic ages: felsite of the Bloomsbury Mountain Formation with a zircon population at 427 Ā± 9 Ma, indicating a Silurian maximum emplacement age, and dacite of the Grassy Lake Formation with several zircon grains at 382.8 Ā± 8.3 Ma, indicating a maximum age of middle Devonian, the first rocks of this age to be identified in the Caledonia terrane
Evidence for the prepattern/cooption model of vertebrate jaw evolution
The appearance of jaws was a turning point in vertebrate evolution because it allowed primitive vertebrates to capture and process large, motile prey. The vertebrate jaw consists of separate dorsal and ventral skeletal elements connected by a joint. How this structure evolved from the unjointed gill bar of a jawless ancestor is an unresolved question in vertebrate evolution. To understand the developmental bases of this evolutionary transition, we examined the expression of 12 genes involved in vertebrate pharyngeal patterning in the modern jawless fish lamprey. We find nested expression of Dlx genes, as well as combinatorial expression of Msx, Hand and Gsc genes along the dorso-ventral (DV) axis of the lamprey pharynx, indicating gnathostome-type pharyngeal patterning evolved before the appearance of the jaw. In addition, we find that Bapx and Gdf5/6/7, key regulators of joint formation in gnathostomes, are not expressed in the lamprey first arch, whereas Barx, which is absent from the intermediate first arch in gnathostomes, marks this domain in lamprey. Taken together, these data support a new scenario for jaw evolution in which incorporation of Bapx and Gdf5/6/7 into a preexisting DV patterning program drove the evolution of the jaw by altering the identity of intermediate first-arch chondrocytes. We present this āPre-pattern/Cooptionā model as an alternative to current models linking the evolution of the jaw to the de novo appearance of sophisticated pharyngeal DV patterning
MicrobeDB: a locally maintainable database of microbial genomic sequences
Summary: Analysis of microbial genomes often requires the general organization and comparison of tens to thousands of genomes both from public repositories and unpublished sources. MicrobeDB provides a foundation for such projects by the automation of downloading published, completed bacterial and archaeal genomes from key sources, parsing annotations of all genomes (both public and private) into a local database, and allowing interaction with the database through an easy to use programming interface. MicrobeDB creates a simple to use, easy to maintain, centralized local resource for various large-scale comparative genomic analyses and a back-end for future microbial application design
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An online study combining the constructs from the theory of planned behaviour and protection motivation theory in predicting intention to test for chlamydia in two testing contexts
Chlamydia is a common sexually-transmitted infection that has potentially serious consequences unless detected and treated early. The health service in the UK offers clinic-based testing for chlamydia but uptake is low. Identifying the predictors of testing behaviours may inform interventions to increase uptake. Self-tests for chlamydia may facilitate testing and treatment in people who avoid clinic-based testing. Self-testing and being tested by a health care professional (HCP) involve two contrasting contexts that may influence testing behaviour. However, little is known about how predictors of behaviour differ as a function of context. In this study, theoretical models of behaviour were used to assess factors that may predict intention to test in two different contexts: self-testing and being tested by a HCP. Individuals searching for, or reading about chlamydia testing online were recruited using Google Adwords. Participants completed an online questionnaire that addressed previous testing behaviour and measured constructs of the Theory of Planned Behaviour and Protection Motivation Theory, which propose a total of eight possible predictors of intention. The questionnaire was completed by 310 participants. Sufficient data for multiple regression were provided by 102 and 118 respondents for self-testing and testing by a HCP respectively. Intention to self-test was predicted by vulnerability and self-efficacy, with a trend-level effect for response efficacy. Intention to be tested by a HCP was predicted by vulnerability, attitude and subjective norm. Thus, intentions to carry out two testing behaviours with very similar goals can have different predictors depending on test context. We conclude that interventions to increase self-testing should be based on evidence specifically related to test context
The impact of labour regulations : measuring the effectiveness of legal norms in a developing country.
Blueberry Research Progress Report
The 1976 edition of the Blueberry Research Progress Report was prepared for the Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Effect of Plant-Water Stress on Lowbush Blueberry Growth, Yield and Quality
2. Insects Affecting the Blueberry
3. The Development of Blueberry Varieties Adapted to Maine
4. Weed Control in Blueberry Fields
5. Pruning of Blueberries
6. Integrated Management of Blueberry Fields
7. The Physiology and Biochemistry of the Development of the Lowbush Blueberry Fruit
8. Survey of Red Leaf Disease of Blueberries
9. Blossom Blight of Blueberries
10. Blueberry Marketing and Cost Analysis of Producing Blueberries
11. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
12. New Food Products and Servic
Reference genome of Lumpfish Cyclopterus lumpus Linnaeus provides evidence of male heterogametic sex determination through the AMH pathway
acceptedVersio
Blueberry Research Progress Report
The 1975 edition of the Blueberry Research Progress Report was prepared for the Blueberry Advisory Committee by researchers at the University of Maine, Orono. Projects in this report include:
1. Insects Affecting the Blueberry
2. Weed Control in Blueberry Fields
3. Pruning of Blueberries
4. Integrated Management of Blueberry Fields
5. Selective Thinning of Black Barrenberries in Lowbush Blueberry Fields with Ethrel
6. The Physiology and Biochemistry of the Development of the Lowbush Blueberry Fruit
7. The Development of Blueberry Varieties Adapted to Maine
8. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
9. Mechanical Blueberry Harvesting
10. Blueberry Marketing and Cost Analysis of Producing Blueberries
11. New Food Products and Servic
Blueberry Progress Reports
The 1978 edition of the Blueberry Progress Reports was prepared for the Maine Blueberry Commission and the University of Maine Blueberry Advisory Committee by researchers with the Maine Life Sciences and Agriculture Experiment Station and Maine Cooperative Extension Service at the University of Maine, Orono. Projects in this report include:
1. Weed Control in Blueberry Fields
2. Pruning of Blueberries
3. Integrated Management of Blueberry Fields
4. Factors Regulating Rhizome Initiation and Development in the Lowbush Blueberry
5. Effect of Plant-Water Stress on Lowbush Blueberry Growth Yield and Quality
6. Blossom Blight of Blueberries
7. Botrytis Blossom Blight of Lowbush Blueberries
8. Insects Affecting the Blueberry
9. Treatment of Blueberries with Potassium Sorbate to Reduce Spoilage During Temporary Storage
10. Cooperative Extension Activitie
Extending colonic mucosal microbiome analysis - Assessment of colonic lavage as a proxy for endoscopic colonic biopsies
This study was supported through GI Research funds and MRC Grant Ref: MR/M00533X/1 to GH.Peer reviewedPublisher PD
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