114 research outputs found
A Plate Type Edge-Lift Anchor: Influence of Reinforcing Configurations on Failure Loads
AS3850 Tilt-up Concrete Construction [1] is the current standard for design of lifting anchors and bracing in Australia. However, this standard does not provide a recommendation for calculating the capacity of edge-lifting anchors (normally placed in the edge of thin wall elements) which are commonly used in the precast industry throughout Australia. These anchors may experience a load under tension or combined tension and shear during the lifting process. The American Concrete Institute (ACI)318-08 Building Code Requirements for Structural Concrete [2], the Precast Concrete Institute (PCI) Design Handbook â Precast and Prestressed Concrete [3], and ComitĂ©Euro-International Du BĂ©ton(CEB)Design of Fastenings in Concrete [4] include provisions for general anchorage configurations (such as multiple face lift anchors) rather than what are typically seen in edgelifting anchors. Not only are anchor configurations for edge lifting anchors different from those described in these standards, but the reinforcement around the anchor can vary significantly to those denoted in standards.This paper is an evaluation of pull out test data for edge lift anchors in thin walled elements. Using the formula in the ACI 318-08 [2], developed predominantly for footed anchors, comparisons of the predicted capacity and the test pull out capacity of the edge lift anchors is made. Data is presented on 154 tests; the variables tested include concrete compressive strength at time of testing and the provision and arrangement of reinforcement. In addition to the edge lift anchors, 90 face lift footed anchors were also tested and some of the more relevant data is presented for these tests
Mining a database of Fungi for Pharmacological Use via Minimum Message Length Encoding
Abstract. This paper concerns the use of fungi in pharmaceutical design. More specifically, this research involves mining a database of fungi to determine which ones have waste products that are unusual in their spectral fingerprints, and therefore worth being tested for medicinal properties. The technique described in this paper involves Minimum Message Length encoding. Minimum Message Length (sometimes called Minimum Description Length) encoding is a method for choosing a binary coding for a set of data. The method's goal is to use the frequency of occurrence of each data point to ensure that frequently occurring data are given short codes. Minimum Message Length encoding provides a solution that is optimal in the sense that if the entire data set is employed in the encoding, then the code generated will have the property that no other unambiguous prefix code will provide a shorter encoded version of the entire set. In this paper, the process is turned on its head. The problem that is addressed is: given a large database, how can we pick out the elements that are quite different from the others. The first step in our solution involves using the Minimum Message Length algorithm to generate a compact code for all, or a representative learning section, of the data. The data that require long descriptions in this code are likely to be the ones that possess unusual features. In this paper, we describe this process in some detail, and explain the application of it to a database of fungi
A comparison of collection management practices between two collections of Diptera.
The Diptera collections of the Natal Museum (Pietermaritzburg, South Africa) and the National Museums of Scotland (Edinburgh, Scotland) are distinctly different. A direct comparison of curatorial techniques aims to assess the methods of collection management used and the constraints facing these two museums.
Each institution has a unique historical background, which has had a particular influence on how collection management practices have developed. Thus, the two museums in question use different techniques to accomplish the same job. These differences are compared and evaluated and the strengths of each institution are highlighted. Some comment on collection management practices in the Diptera collections of other museums is included.
The main limitation facing the National Museums of Scotland collection stems from its age and certain traditional methods of organisation used. Being a younger collection, the Diptera collection at the Natal Museum is largely free from such limitations.
Current political and economic factors are discussed relative to operations at both museums. These factors (including the means by which finances are obtained) affect differently the two institutions and what they expect from their staff. As a result, collection management practices are also distinctively influenced.
Certainly, some positive changes can be made to improve the Diptera collections at National Museums of Scotland, but the constraints facing the Natal Museum are more complicated and sometimes more difficult to overcome
The Australian Space Eye: studying the history of galaxy formation with a CubeSat
The Australian Space Eye is a proposed astronomical telescope based on a 6U
CubeSat platform. The Space Eye will exploit the low level of systematic errors
achievable with a small space based telescope to enable high accuracy
measurements of the optical extragalactic background light and low surface
brightness emission around nearby galaxies. This project is also a demonstrator
for several technologies with general applicability to astronomical
observations from nanosatellites. Space Eye is based around a 90 mm aperture
clear aperture all refractive telescope for broadband wide field imaging in the
i and z bands.Comment: 19 pages, 14 figures, submitted for publication as Proc. SPIE 9904,
9904-56 (SPIE Astronomical Telescopes & Instrumentation 2016
High yielding biomass ideotypes of willow (Salix spp.) show differences in below ground biomass allocation.
Willows (Salix spp.) grown as short rotation coppice (SRC) are viewed as a sustainable source of biomass with a positive greenhouse gas (GHG) balance due to their potential to fix and accumulate carbon (C) below ground. However, exploiting this potential has been limited by the paucity of data available on below ground biomass allocation and the extent to which it varies between genotypes. Furthermore, it is likely that allocation can be altered considerably by environment. To investigate the role of genotype and environment on allocation, four willow genotypes were grown at two replicated field sites in southeast England and west Wales, UK. Above and below ground biomass was intensively measured over two two-year rotations. Significant genotypic differences in biomass allocation were identified, with below ground allocation differing by up to 10% between genotypes. Importantly, the genotype with the highest below ground biomass also had the highest above ground yield. Furthermore, leaf area was found to be a good predictor of below ground biomass. Growth environment significantly impacted allocation; the willow genotypes grown in west Wales had up to 94% more biomass below ground by the end of the second rotation. A single investigation into fine roots showed the same pattern with double the volume of fine roots present. This greater below ground allocation may be attributed primarily to higher wind speeds, plus differences in humidity and soil characteristics. These results demonstrate that the capacity exists to breed plants with both high yields and high potential for C accumulation
Do Global Diversity Patterns of Vertebrates Reflect Those of Monocots?
Few studies of global diversity gradients in plants exist, largely because the data are not available for all species involved. Instead, most global studies have focussed on vertebrates, as these taxa have historically been associated with the most complete data. Here, we address this shortfall by first investigating global diversity gradients in monocots, a morphologically and functionally diverse clade representing a quarter of flowering plant diversity, and then assessing congruence between monocot and vertebrate diversity patterns. To do this, we create a new dataset that merges biome-level associations for all monocot genera with country-level associations for almost all ∼70,000 species. We then assess the evidence for direct versus indirect effects of this plant diversity on vertebrate diversity using a combination of linear regression and structural equation modelling (SEM). Finally, we also calculate overlap of diversity hotspots for monocots and each vertebrate taxon. Monocots follow a latitudinal gradient although with pockets of extra-tropical diversity, mirroring patterns in vertebrates. Monocot diversity is positively associated with vertebrate diversity, but the strength of correlation varies depending on the clades being compared. Monocot diversity explains marginal amounts of variance (<10%) after environmental factors have been accounted for. However, correlations remain among model residuals, and SEMs apparently reveal some direct effects of monocot richness. Our results suggest that collinear responses to environmental gradients are behind much of the congruence observed, but that there is some evidence for direct effects of producer diversity on consumer diversity. Much remains to be done before broad-scale diversity gradients among taxa are fully explained. Our dataset of monocot distributions will aid in this endeavour
Introgression across evolutionary scales suggests reticulation contributes to Amazonian tree diversity
This is the final version. Available from Wiley via the DOI in this record.The data that support the findings of this study are openly available from online repositories. All raw reads generated with the targeted bait capture and ddRADseq methods are available on the NCBI Sequence Read Archive with the Accession nos SAMN13439069âSAMN13439140 and SAMN13441804âSAMN13441974, respectively, under the BioProject number PRJNA592723. All full phylogenomic sequence alignments, singleâaccessionâperâspecies alignments and tree files, bgc input files, Stacks output files and the Detarioideae bait kit sequence file are found on Dryad (https://doi.org/10.5061/dryad.k3j9kd53w). Data are under embargo until publication, and any further data required are available from the corresponding author upon reasonable request.Hybridization has the potential to generate or homogenize biodiversity and is a particularly common phenomenon in plants, with an estimated 25% of plant species undergoing interspecific gene flow. However, hybridization in Amazonia's megadiverse tree flora was assumed to be extremely rare despite extensive sympatry between closely related species, and its role in diversification remains enigmatic because it has not yet been examined empirically. Using members of a dominant Amazonian tree family (Brownea, Fabaceae) as a model to address this knowledge gap, our study recovered extensive evidence of hybridization among multiple lineages across phylogenetic scales. More specifically, using targeted sequence capture our results uncovered several historical introgression events between Brownea lineages and indicated that gene tree incongruence in Brownea is best explained by reticulation, rather than solely by incomplete lineage sorting. Furthermore, investigation of recent hybridization using ~19,000 ddRAD loci recovered a high degree of shared variation between two Brownea species that co-occur in the Ecuadorian Amazon. Our analyses also showed that these sympatric lineages exhibit homogeneous rates of introgression among loci relative to the genome-wide average, implying a lack of selection against hybrid genotypes and persistent hybridization. Our results demonstrate that gene flow between multiple Amazonian tree species has occurred across temporal scales, and contrasts with the prevailing view of hybridization's rarity in Amazonia. Overall, our results provide novel evidence that reticulate evolution influenced diversification in part of the Amazonian tree flora, which is the most diverse on Earth.Natural Environment Research Council (NERC)Genetics Societ
Leaf photosynthesis and associations with grain yield, biomass and nitrogen-use efficiency in landraces, synthetic-derived lines and cultivars in wheat
Future genetic progress in wheat grain yield will depend on increasing above-ground biomass and this must be achieved without commensurate increases in N fertilizer inputs to minimise environmental impacts. Our objective was to quantify variation in grain yield, above-ground biomass and N-use efficiency (NUE) and associated traits in a panel of diverse hexaploid wheat germplasm comprising: (i) landraces from the AE Watkins collection, (ii) synthetic-derived hexaploid lines in a cv. Paragon spring wheat background and (iii) UK modern cultivars including cv. Paragon under low N and high N conditions. A field experiment was carried out in two seasons examining 15 genotypes (five landraces, five synthetic-derived (SD) hexaploid lines and five UK modern cultivars) under low N and high N conditions at Nottingham University farm, UK. Machine-harvested grain yield, above-ground biomass and NUE were measured. Physiological traits were assessed including flag-leaf light-saturated photosynthetic rate (Amax) and relative chlorophyll content (SPAD) under HN conditions; and flag-leaf senescence duration and rate and Normalized Difference Vegetative Index (NDVI) under LN and HN conditions. Under HN conditions, the modern cultivars overall produced higher grain yield than the SD lines (+9.7%) and the landraces (+60.4%); and the modern cultivars and SD lines also produced higher biomass than the landraces (30.3% and 28.4%, respectively). Under LN conditions, reduction in grain yield and biomass compared to HN conditions was least for the landraces (â1% and â8.6%, respectively), intermediate for the SD lines (â7.4 and â10.2%, respectively) and highest for the modern cultivars (â9.3 and â24.6%, respectively). As a result, the SD lines had higher biomass (+17%) than the modern cultivars under LN conditions. Under HN conditions the synthetic derivatives (23.8 ÎŒmol mâ2 sâ1) and modern cultivars (241.1 ÎŒmol mâ2 sâ1) had higher pre-anthesis Amax than the landraces (19.7 ÎŒmol mâ2 sâ1) (P < 0.001). Pre-anthesis Amax was strongly positively linearly associated with above-ground biomass (R2 = 0.63, P < 0.001) and grain yield (R2 = 0.75, P < 0.001) amongst the 15 genotypes. Flag-leaf Amax was also positively linearly associated with flag-leaf relative chlorophyll content at anthesis (R2 = 0.74; P < 0.001). Comparing the SD lines to the recurrent parent Paragon, under HN conditions one line (SD 22) had higher pre-anthesis flag-leaf Amax than Paragon (P < 0.05). Under LN conditions one line (SD 24, +27%) had higher yield than Paragon (P < 0.05) and two lines (SD 24 and SD 38, +32% and +31%, respectively) had more biomass than Paragon (P < 0.05). Our results indicated that introgressing traits from synthetic-derived wheat and landraces into UK modern wheat germplasm offers scope to raise above-ground biomass and grain yield in moderate-to-low N availability environments
2015 recommendations for the management of polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative
Therapy for polymyalgia rheumatica (PMR) varies widely in clinical practice as international recommendations for PMR treatment are not currently available. In this paper, we report the 2015 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) recommendations for the management of PMR. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology as a framework for the project. Accordingly, the direction and strength of the recommendations are based on the quality of evidence, the balance between desirable and undesirable effects, patients'and clinicians'values and preferences, and resource use. Eight overarching principles and nine specific recommendations were developed covering several aspects of PMR, including basic and follow-up investigations of patients under treatment, risk factor assessment, medical access for patients and specialist referral, treatment strategies such as initial glucocorticoid (GC) doses and subsequent tapering regimens, use of intramuscular GCs and disease modifying anti-rheumatic drugs (DMARDs), as well as the roles of non-steroidal anti-rheumatic drugs and non-pharmacological interventions. These recommendations will inform primary, secondary and tertiary care physicians about an international consensus on the management of PMR. These recommendations should serve to inform clinicians about best practices in the care of patients with PMR
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