2,407 research outputs found
New looks at and for Onespa, Buzyges, and Librita (Lepidoptera: Hesperiidae: Hesperiinae), with new combinations and descriptions of a new genus and six new species
Thirteen species of skippers (six newly described; Lepidoptera: Hesperiidae: Hesperiinae: Hesperiini) from higher elevations of Mexico and Central America are reviewed. These are included in four genera (one newly described), some with proposed new combinations. Onespa Steinhauser, 1974, originally described as monotypic, is shown to include three species in addition to its type species, Onespa nubis Steinhauser, 1974. One of these, Atrytone gala Godman, 1900, that has been misplaced in several genera since its description, represents a new combination. The other two species, distributed in montane habitats in northwestern Mexico and in Costa Rica, are described as new. Buzyges Godman, 1900, distributed in Mexico and Central America and also formerly considered monotypic, is shown to embrace four species. Besides the type species, Buzyges idothea Godman, 1900, two species long placed in Poanes Scudder, 1872, Pamphila rolla Mabille, 1883, and Poanes benito Freeman, 1979, are included as new combinations. Another species, known only from Costa Rica, is described as new. These are united by several superficial characters, but especially by genital morphology of both sexes. Librita Evans, 1955, was described to include three species of which one, Librita raspa Evans, 1955, was subsequently removed. Augiades heras Godman, 1900 is here also removed from Librita and placed in a new genus with three previously undescribed species. This completes the disintegration of Librita, which is now monotypic. The four genera, although exhibiting similarities suggesting potential alliance, differ in their unique combinations of several superficial and genital traits from each other and other hesperiine skippers
The type of Copaeodes chromis Skinner, 1919 (Lepidoptera: Hesperiidae: Hesperiinae)
The holotype of Copaeodes chromis Skinner, 1919 (Lepidoptera: Hesperiidae), housed at the Carnegie Museum of Natural History, is a typical specimen of Zariaspes mythecus Godman, 1900
Regaining their cool : can the big three surf brands recover?
Australia\u27s big three surf brands have found themselves in choppy financial waters.
Last week, Billabong, one of Australia\u27s most iconic surf brands confirmed a 859 million loss last financial year.
Like Billabong, public surf company Quiksilver has reported declining revenues, asset write-downs and growing losses, recently announcing third-quarterly earnings had declined 84%. Privately-owned Rip Curl has also been in profit free-fall. In mid-2012 Rip Curl founders Brian Singer and Doug Warbrick engaged Bank of America Merrill Lynch to help source a prospective buyer for the brand. The planned sale was abandoned in March with a lack of interest at the asking price of $400 million.
The current woes are a long way from the heady days of the 1990s and 2000s, which saw each of the big three surf brands aggressively pursue international expansion and high-profile sports sponsorship deals.
So, why have the Big Three surf brands found themselves struggling? And what is the way to calmer waters
Resource-sensitive global production networks: reconfigured geographies of timber and acoustic guitar manufacturing
This article examines how resource materiality, scarcity, and evolving international environmental regulation shape global production networks (GPNs). Nature-facing elements, including resource scarcity and environmental regulation, have seldom featured in GPN analysis. So, too, GPN analysis emphasizes spatial relations between network actors over temporal change. We extend GPN theorization through a temporal analysis of industrial change, connecting manufacturing to upstream resource materialities and shifting regulation, and to downstream consumers increasingly concerned with provenance and material stewardship. To illustrate, we document a resource-sensitive GPN-acoustic guitar manufacturing-where scarcity of select raw materials (tonewoods) with material qualities of resonance, strength, and beauty, as well as tighter regulation, has spawned shifting economic geographies of new actors who influence the whole GPN. Such actors include specialist extraction firms, salvagers, traders, verification consultants, and customs agents who innovate in procurement and raw material supply risk management. Traditional large guitar manufacturing firms have struggled with regulation and securing consistent resource supply, although smaller lead manufacturing firms have creatively responded via novel procurement methods and marketing, developing closely bound, iterative relationships with specialist timber harvesters, traders, and with emotionally attached consumers. A cohort of tonewood supply firms and guitar manufacturers-especially in Australia, the Pacific Northwest and Canada, key locations of both resource and design expertise-have together altered material stewardship practices and commodity production. Niche strategies derive exchange value from rarity and resource innovation, embracing raw material variability, inconsistent supply, and the need for alternatives. How firms adapt to resource supply security risks, we argue, is an imperative question for GPN analysis
Implementing A Business Intelligence (BI)/Corporate Performance Management (CPM) Solution: Challenges Faced By A Major National Retailer
Based on actual events, this case is concerned with the practical and managerial challenges associated with analyzing, designing and implementing a Business Intelligence (BI) / Corporate Performance Management (CPM)information technology solution in a large national retailer. Secondary issues examined include strategy, project management and conflict resolution. This case is appropriate for upper-level undergraduate and masters-level graduate courses in information technology, accounting information systems and project management. It is designed to be taught in about one class hour, and requires four to six hours of outside preparation by students.
Geographic variability in lidar predictions of forest stand structure in the Pacific Northwest
Estimation of the amount of carbon stored in forests is a key challenge for understanding the global carbon cycle, one which remote sensing is expected to help address. However, carbon storage in moderate to high biomass forests is difficult to estimate with conventional optical or radar sensors. Lidar (light detection and ranging) instruments measure the vertical structure of forests and thus hold great promise for remotely sensing the quantity and spatial organization of forest biomass. In this study, we compare the relationships between lidar measured canopy structure and coincident field measurements of forest stand structure at five locations in the Pacific Northwest of the U.S.A. with contrasting composition. Coefficient of determination values (r2) ranged between 41% and 96%. Correlations for two important variables, LAI (81%) and above ground biomass (92%), were noteworthy, as was the fact that neither variable showed an asymptotic response.
Of the 17 stand structure variables considered in this study, we were able to develop eight equations that were valid for all sites, including equations for two variables generally considered to be highly important (aboveground biomass and leaf area index). The other six equations that were valid for all sites were either related to height (which is most directly measured by lidar) or diameter at breast height (which should be closely related to height). Four additional equations (a total of 12) were applicable to all sites where either Douglas-fir (Pseudotsuga menziesii), western hemlock (Tsuga heterophylla) or Sitka spruce (Picea sitchensi) were dominant. Stand structure variables in sites dominated by true firs (Abies sp.) or ponderosa pine (Pinus ponderosa) had biases when predicted by these four additional equations. Productivity-related variables describing the edaphic, climatic and topographic environment of the sites where available for every regression, but only two of the 17 equations (maximum diameter at breast height, stem density) incorporated them. Given the wide range of these environmental conditions sampled, we conclude that the prediction of stand structure is largely independent of environmental conditions in this study area.
Most studies of lidar remote sensing for predicting stand structure have depended on intensive data collections within a relatively small study area. This study indicates that the relationships between many stand structure indices and lidar measured canopy structure have generality at the regional scale. This finding, if replicated in other regions, would suggest that mapping of stand structure using lidar may be accomplished by distributing field sites extensively over a region, thus reducing the overall inventory effort required
Disruption of PCNA-lamins A/C interactions by prelamin A induces DNA replication fork stalling
The accumulation of prelamin A is linked to disruption of cellular homeostasis, tissue degeneration and aging. Its expression is implicated in compromised genome stability and increased levels of DNA damage, but to date there is no complete explanation for how prelamin A exerts its toxic effects. As the nuclear lamina is important for DNA replication we wanted to investigate the relationship between prelamin A expression and DNA replication fork stability. In this study we report that the expression of prelamin A in U2OS cells induced both mono-ubiquitination of proliferating cell nuclear antigen (PCNA) and subsequent induction of Pol η, two hallmarks of DNA replication fork stalling. Immunofluorescence microscopy revealed that cells expressing prelamin A presented with high levels of colocalisation between PCNA and γH2AX, indicating collapse of stalled DNA replication forks into DNA double-strand breaks. Subsequent protein-protein interaction assays showed prelamin A interacted with PCNA and that its presence mitigated interactions between PCNA and the mature nuclear lamina. Thus, we propose that the cytotoxicity of prelamin A arises in part, from it actively competing against mature lamin A to bind PCNA and that this destabilises DNA replication to induce fork stalling which in turn contributes to genomic instability
Prelamin A impairs 53BP1 nuclear entry by mislocalizing NUP153 and disrupting the Ran gradient.
The nuclear lamina is essential for the proper structure and organization of the nucleus. Deregulation of A-type lamins can compromise genomic stability, alter chromatin organization and cause premature vascular aging. Here, we show that accumulation of the lamin A precursor, prelamin A, inhibits 53BP1 recruitment to sites of DNA damage and increases basal levels of DNA damage in aged vascular smooth muscle cells. We identify that this genome instability arises through defective nuclear import of 53BP1 as a consequence of abnormal topological arrangement of nucleoporin NUP153. We show for the first time that this nucleoporin is important for the nuclear localization of Ran and that the deregulated Ran gradient is likely to be compromising the nuclear import of 53BP1. Importantly, many of the defects associated with prelamin A expression were significantly reduced upon treatment with Remodelin, a small molecule recently reported to reverse deficiencies associated with abnormal nuclear lamina.British Heart Foundation (Grant ID: RG/11/14/29056), Medical Research Council (Grant ID: MR/L019116/1), Cancer Research UK (Grant IDs: C6/A11224, C6946/A14492), European Research Council, European Community Seventh Framework Programme (Grant ID: HEALTH-F2-2010-259893) , Wellcome Trust (Grant ID: WT092096), University of CambridgeThis is the final version of the article. It first appeared from Wiley via http://dx.doi.org/10.1111/acel.1250
Functional insights from the structure of the 30S ribosomal subunit and its interactions with antibiotics
The 30S ribosomal subunit has two primary functions in protein synthesis. It discriminates against aminoacyl transfer RNAs that do not match the codon of messenger RNA, thereby ensuring accuracy in translation of the genetic message in a process called decoding. Also, it works with the 50S subunit to move the tRNAs and associated mRNA by precisely one codon, in a process called translocation. Here we describe the functional implications of the high-resolution 30S crystal structure presented in the accompanying paper, and infer details of the interactions between the 30S subunit and its tRNA and mRNA ligands. We also describe the crystal structure of the 30S subunit complexed with the antibiotics paromomycin, streptomycin and spectinomycin, which interfere with decoding and translocation. This work reveals the structural basis for the action of these antibiotics, and leads to a model for the role of the universally conserved 16S RNA residues A1492 and A1493 in the decoding process
Additive Manufacturing, Modeling and Performance Evaluation of 3D Printed Fins for Surfboards
We demonstrate that Additive Manufacturing (3D printing) is a viable approach to rapidly prototype personalised fins for surfboards. Surfing is an iconic sport that is extremely popular in coastal regions around the world. We use computer aided design and 3D printing of a wide range of composite materials to print fins for surfboards, e.g. ABS, carbon fibre, fibre glass and amorphous thermoplastic poly(etherimide) resins. The mechanical characteristics of our 3D printed fins were found to be comparable to commercial fins. Computational fluid dynamics was employed to calculate longitudinal (drag) and tangential (turning) forces, which are important for surfboard maneuverability, stability and speed. A commercial tracking system was used to evaluate the performance of 3D printed fins under real-world conditions (i.e. surfing waves). These data showed that the surfing performance of surfboards with 3D printed fins is similar to that of surfboards with commercial fins
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