bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insect resistance to Bt toxins in Brazil and Latin America.
Authors: Monnerat R. , Martins E. , Queiroz P. , Praça L. , Soares C. M. 
Published: May 2015

Abstract

Bioinsecticides based on Bacillus thuringiensis (Bt) and transgenic plants expressing its toxins have been widely used to control insects in Latin America. In Brazil, during the season of 2013/14, 4 million ha were treated with Bt biopesticides, and the area of transgenic crops under cultivation reached 40.3 million ha. Countries such as Honduras, Guatemala, Costa Rica, Nicaragua and Brazil reported cases of resistance of Plutella xylostella to Bt biopesticides. Insect resistance to toxins expressed in Bt crops was reported in Puerto Rico and Brazil, and reports of low efficacy were also communicated from several regions of Brazil and Argentina. Faced to this scenario, it is important that companies providing technologies, extension services, farmers and the scientific community and governments of countries either using Bt as bioinsecticides or as Bt crops unite in their efforts to establish guidelines that will enable greater durability of Bt technology.
Mechanism of Cry1Ac resistance in cabbage loopers - a resistance mechanism selected in insect populations in an agricultural environment.
Authors: Wang P. 
Published: May 2015

Abstract

The development of resistance to Bacillus thuringiensis (Bt) in insect populations in agriculture not only depends on the level of resistance conferred by a selected resistance mechanism, but also on the fitness cost associated with the resistance mechanism under specific ecological and environmental conditions. Bt resistance in the cabbage looper (Trichoplusia ni), which was identified by Janmaat and Myers (2003), is a case of Bt resistance evolved in an agricultural system, and is used in this chapter to review and discuss the mechanism of Cry1Ac resistance that is selected in an agricultural environment.
Roles of ABC proteins in the mechanism and management of Bt resistance.
Authors: Heckel D. G. 
Published: May 2015

Abstract

Genetic studies of strains of insects that have developed resistance to pore-forming Cry toxins from Bacillus thuringiensis (Bt) have provided useful and unexpected insights into the mode of action of the toxin. Independent approaches in five species of Lepidoptera have converged on the same result: that mutations in a member of the superfamily of ABC transporters confer resistance to Cry toxins. These mutations range from a single amino acid insertion to truncations that delete most of the protein. This result is surprising, because since the first detection of the specific binding of Cry toxins to sites in the lepidopteran midgut in 1988, no studies had documented any sort of interaction between Cry toxins and ABC proteins. It is hypothesized that ABC transporters mediate the critical step of Cry pore insertion into the membrane. Heterologous expression of ABC proteins has recently shown that they can facilitate cell swelling by Cry toxins, which is indirect evidence of pore formation. It is suggested that the 'ATP-switch' mechanism of ABC proteins that drives the transport of small molecules across cell membranes might be exploited to potentiate Bt action and to guide the design of improved Cry toxins.
The lessons that Caenorhabditis elegans has taught us about the mechanism of action of crystal proteins.
Authors: Sitaram A. , Aroian R. V. 
Published: May 2015

Abstract

Caenorhabditis elegans is susceptible to three domain crystal proteins similar to those that intoxicate insects. Investigations of this organism have several important strengths, for example, ease of forward genetic screens, range of molecular genetic tools available and ease of carrying out RNAi (RNA interference) studies. These have been exploited to study cellular responses known as cellular non-immune defences (CNIDs) to the crystal proteins of Bacillus thuringiensis (Bt) and pore-forming toxins in general. We will discuss what we have learned through genetics and RNAi (including genome-wide RNAi) to elucidate the pathways that allow cells to respond productively to crystal protein attack. In addition, key results will be discussed from investigations with mammalian pore-forming proteins to highlight the conservation of cellular responses to crystal proteins with cellular responses to pore-forming proteins in general.
Cry toxin binding site models and their use in strategies to delay resistance evolution.
Authors: Jakka S. , Ferré J. , Jurat-Fuentes J. L. 
Published: May 2015

Abstract

The binding of Cry toxins to receptors on the midgut brush border membrane is a necessary step in the Cry intoxication process. Alterations in this binding step are commonly associated with high levels of resistance to Cry toxins in laboratory and field pest populations. When alterations affect binding to a site shared by distinct Cry toxins, cross-resistance is observed. Consequently, pyramiding of Cry toxins recognizing distinct sites has been used to delay the evolution of resistance against transgenic crops expressing cry toxin genes for pest control. The availability of accurate binding site models describing binding sites for diverse Cry toxins in targeted pests is critical to identifying genes that are amenable to pyramiding. Many of these models have been proposed and refined in the past 25 years from quantitative binding competition data. In this chapter, we review and revise Cry toxin binding site models for the most relevant pest species targeted by Bt crops and for Plutella xylostella as the insect pest with the most binding data available. Our motivation is to provide binding site models as a tool to allow predictions of resistance and cross-resistance risks in order to optimize combinations of diverse Cry toxins for delaying resistance evolution to Bt crops.
Countering pest resistance with genetically modified Bt toxins.
Authors: Soberón M. , García-Gómez B. I. , Pacheco S. , Sánchez J. , Tabashnik B. E. , Bravo A. 
Published: May 2015

Abstract

Insecticidal crystalline (Cry) toxins from the bacterium Bacillus thuringiensis (Bt) used in sprays and transgenic crop plants have provided major benefits for pest control, including decreased reliance on broad-spectrum chemical insecticides. However, extensive use of Bt toxins has selected for resistance, thus reducing or eliminating these benefits against some populations of at least seven species of major crop pests. This chapter reviews efforts to counter pest resistance to native Bt toxins with genetically engineered toxins called Cry1AbMod and Cry1AcMod. We generated these modified toxins by trimming the genes encoding the native toxins Cry1Ab and Cry1Ac so they lack the nucleotides that code for a portion of the amino-terminal end of the protein, including helix α-1 and part of helix α-2. Consistent with the sequential binding model for the mode of action of the toxins, the Cry1AMod toxins formed oligomers without binding to cadherin, but the native toxins required cadherin for oligomer formation. The modified toxins were more potent than the corresponding native toxins in 13 of 19 pairwise comparisons with 12 resistant strains of nine species of Lepidoptera, including field-selected strains of Plutella xylostella, Trichoplusia ni and Spodoptera frugiperda. The potency of modified toxins relative to native toxins in these resistant strains did not depend on the resistance mechanism. Against susceptible strains, the modified toxins were less effective than their native counterparts in nearly all cases. Transgenic tobacco plants producing Cry1AbMod killed larvae of Manduca sexta, which represents progress towards commercial use of the modified toxins for pest management.
Resistance management for Bt maize and above-ground lepidopteran targets in the USA: from single gene to pyramided traits.
Authors: Huang F. N. 
Published: May 2015

Abstract

Since first being commercialized in 1996, transgenic maize expressing Bacillus thuringiensis (Bt) proteins has gained widespread acceptance in the world. In 2013, nearly 50 Mha of Bt maize were planted in 15 countries. In the same year, growers in the USA alone planted c.30 Mha of Bt maize, which accounted for 76% of the total Bt maize area of the country. Up to now, Bt maize technology can be classified into two generations. The first generation of Bt maize contains only a single Bt gene for a target. In 2010, the second generation of Bt maize became commercially available and this expresses two or more pyramided Bt proteins. Currently, the pyramided products are predominant in the USA. The major lepidopteran targets of Bt maize in the USA are corn borers (Crambidae), the corn earworm, Helicoverpa zea, and the fall armyworm, Spodoptera frugiperda. To counter the threat of insect resistance, two resistance management strategies for Bt maize, 'high dose/refuge' and gene pyramiding, have been implemented. The long-term use of Bt maize against the major agricultural pests in North America provides a good opportunity to analyse the effectiveness of the adopted insect resistance management (IRM) plans. Analysis of the available data shows that all corn borer species remain susceptible to Bt proteins and that no field resistance has occurred after nearly two decades of intensive use of Bt maize in the continent. Pyramided Bt maize is effective in controlling corn earworm and fall armyworm, although recent studies indicate that field resistance to single-gene Cry1F maize in the fall armyworm has occurred in the south-east coastal areas of the US mainland. Knowledge of the resistance management gained from the USA should be useful for other countries in their sustainable use of Bt crop technology.
Can Conservation Stocking Enhance Juvenile Emigrant Production in Wild Atlantic Salmon?
Authors: Bacon P. J. , Malcolm I. A. , Fryer R. J. , Glover R. S. , Millar C. P. , Youngson A. F. 
Published: May 2015

AbstractConservation stocking is frequently used by fishery managers to stabilize or increase production of depleted fish stocks. However, in the case of salmonids the benefits are increasingly questioned and generally poorly quantified. We investigated the effects of ova stocking on freshwater emigrant production in a declining Scottish population of “spring” Atlantic SalmonSalmo salar. The stocking program was designed to minimize risks, maximize expected benefits, and bypass population bottlenecks between the ova and fry stages. Long‐term data (33 cohorts over 42 years, including 8 years of stocking) on numbers of ova and juvenile emigrant production were used to investigate whether the ova–emigrant stock–recruitment relationship differed between conditions of natural spawning and stocking. We considered Ricker and Beverton–Holt models that included terms for the effects of stocking, intercohort competition, and changes in trap efficiency on emigrant production. The “best model” was considered to be that with the lowest corrected Akaike information criterion (AICc). The strength of evidence for competing models was provided by smooth AICcweights. There was strong support for intercohort competition whereby large cohorts reduced survival rates of subsequent cohorts. There was little support for a stocking effect, and the best model did not include stocking. Changes in juvenile emigrant production could have been detected with 80% power if those changes had increased by an average of around 24% over the eight stocked years, indicating relatively high power to detect stocking effects. Although focused on a particular river system and set of ova stocking protocols, this study suggests that stocking fails to increase Atlantic Salmon production where wild fish populations and suitable habitat remain.
Macroeconomic Theory
Authors: Benassy Jean-Pascal 
Published: May 2015

AbstractThis book is a primer in macroeconomics. It starts from essential macroeconomics and develops the central topics of modern macroeconomic theory in a simple and rigorous manner. Topics covered include rational expectations, intertemporal dynamic models, exogenous and endogenous growth, nonclearing markets and imperfect competition, uncertainty, and money. The book also covers real business cycles and dynamic stochastic general equilibrium models, integrating growth and fluctuations, sticky wages and prices, consumption and investment, and unemployment. Lastly, it studies government policy, stabilization, credibility, and the connections between politics and the macroeconomy. Each topic is presented in the simplest model possible while still delivering the relevant answers and keeping rigorous foundations throughout the book.
Uncertainty and Financial Assets
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter provides an overview of uncertainty at the individual and general equilibrium level. It evaluates the behavior of an individual who has to take decisions in uncertain environments. It looks at the traditional expected utility maximization theory, and also provides a few measures of risk aversion. Further, it presents the most classic model of general equilibrium under uncertainty, the Arrow-Debreu model, which is also called a model with “complete markets.” This model conventionally serves as a central benchmark to which other concepts are compared. The chapter then describes the models of “incomplete markets.” It confers a general description of financial securities, and explains the disparity between a complete market and incomplete market. Moreover, it discusses the financial assets pricing in complete or an incomplete markets. It shows the application of the pricing formulas to compare safe and risky assets. Lastly, it sets forth the idea of “nonexpected utility,” which sorts out the concepts of risk aversion and substitutability.
The Ramsey Model
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter introduces the most famous model of growth, the Ramsey model. The rate growth in the Ramsey model is principally determined by the evolution of technology, which is assumed to be exogenous. The chapter illustrates a state of intertemporal market equilibrium, and evaluates the efficiency properties of the market equilibrium. Also, it examines an important property of the Ramsey model, that of Ricardian equivalence. It reveals how the introduction of government spending alters the dynamics of the model. Further, it presents a state of unambiguous exogenous technical progress, and demonstrates how the basic model is adapted to incorporate such technical progress. The chapter then discusses the Ramsey model in discrete time.
Competitive Business Cycles
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter discusses the three lines of research used in assessing basic models of fluctuations in competitive markets, namely research with the use of Dynamic Stochastic General Equilibrium models, a typical Sunspot model, and a combination of Keynesian theory, the Samuelson destabilizing accelerator, and the Philips curve. It explains that the Dynamic Stochastic General Equilibrium models provide simpler solutions, as they answer simple first-order conditions of asset pricing, and address labor fluctuations. This chapter also includes sample problems regarding alternative shocks in the government and households, incomplete capital depreciation, a Real Business Cycle model with generations, and with autocorrelated shocks.
Money and Cycles
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter extends the discussion on realistic economies with monetary exchange and assumptions of price flexibility mentioned in Chapter 10 by incorporating the three important features, namely monetary shocks, imperfect competition, and imperfect information. It deals with the relation of the application of simple real models to these shocks while taking into account Walrasian equilibrium theory. The chapter argues that preserving the monetary structure, the theory may become inapplicable. It also explains that imperfect information present in Lucas’ model can lead to misunderstanding of these shocks. This chapter also includes sample problems regarding money and imperfect competition on goods and labor markets and Lucas’ signal extraction model.
Unemployment
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter examines various explanations for theories of employment fluctuations. It begins with looking at alternative unemployment theories and placing them into a unified framework to emphasize their prominent features. It also considers the discourse on the three classic models of trade union behavior: monopoly trade union, efficient bargains, and the “right to manage” model. In addition, it highlights the concepts of “insider-outsiders” theory, efficiency wage theories, and implicit contracts theories. This chapter includes sample problems regarding the tax scheme to fight unemployment and the simple model of nominal wage rigidity.
A Dynamic View of Unemployment
Authors: Bénassy Jean-Pascal 
Published: May 2015

AbstractThis chapter discusses the problem of unemployment in a dynamic and intertemporal framework. It emphasizes flows in and out of unemployment through the matching function model. It explains a simple common discrete time dynamic framework, as well as the basic employment flows. It also focuses on the shirking model to show how one can go from a static to a dynamic model by extending to a dynamic environment.
Late Classical and Hellenistic Silver Plate from Macedonia
Authors: Zimi Eleni 
Published: May 2015

AbstractThis book studies silver vessels from ancient Macedonia from the 4th to the 2nd centuries bc. These precious vessels formed part of dining sets owned by the royal family and the elite and have been discovered in the tombs of their owners. The book presents 171 artifacts in a study of form, decoration, inscriptions, and manufacturing techniques, set against contemporary comparanda in other media (clay, bronze, glass). It adopts an art historical and sociological approach to the archaeological evidence and demonstrates that the use of silver vessels as an expression of wealth and a status symbol is not only connected with the wealth spread in the empire after Alexander’s the Great expedition to the East, but constitutes a practice reflecting the opulence and appreciation for luxury at least in the Macedonian court from the reign of Philip II onwards.
Phylesystem: a git-based data store for community-curated phylogenetic estimates
Authors: McTavish Emily Jane , Hinchliff Cody E. , Allman James F. , Brown Joseph W. , Cranston Karen A. , Holder Mark T. , Rees Jonathan A. , Smith Stephen A. 
Published: May 2015

Abstract
Motivation: Phylogenetic estimates from published studies can be archived using general platforms like Dryad (Vision, 2010) or TreeBASE (Sanderson et al., 1994). Such services fulfill a crucial role in ensuring transparency and reproducibility in phylogenetic research. However, digital tree data files often require some editing (e.g. rerooting) to improve the accuracy and reusability of the phylogenetic statements. Furthermore, establishing the mapping between tip labels used in a tree and taxa in a single common taxonomy dramatically improves the ability of other researchers to reuse phylogenetic estimates. As the process of curating a published phylogenetic estimate is not error-free, retaining a full record of the provenance of edits to a tree is crucial for openness, allowing editors to receive credit for their work and making errors introduced during curation easier to correct.
Results: Here, we report the development of software infrastructure to support the open curation of phylogenetic data by the community of biologists. The backend of the system provides an interface for the standard database operations of creating, reading, updating and deleting records by making commits to a git repository. The record of the history of edits to a tree is preserved by git’s version control features. Hosting this data store on GitHub (http://github.com/) provides open access to the data store using tools familiar to many developers. We have deployed a server running the ‘phylesystem-api’, which wraps the interactions with git and GitHub. The Open Tree of Life project has also developed and deployed a JavaScript application that uses the phylesystem-api and other web services to enable input and curation of published phylogenetic statements.
Availability and implementation: Source code for the web service layer is available at https://github.com/OpenTreeOfLife/phylesystem-api. The data store can be cloned from: https://github.com/OpenTreeOfLife/phylesystem. A web application that uses the phylesystem web services is deployed at http://tree.opentreeoflife.org/curator. Code for that tool is available from https://github.com/OpenTreeOfLife/opentree.
Contact: mtholder@gmail.com
Vertical and horizontal habitat use by white marlin Kajikia albida (Poey, 1860) in the western North Atlantic Ocean
Authors: Hoolihan John P. , Luo Jiangang , Snodgrass Derke , Orbesen Eric S. , Barse Ann M. , Prince Eric D. 
Published: May 2015

Abstract
Pop-up satellite archival tags were deployed on 40 white marlin Kajika albida (synonym: Tetrapturus albidus) off the coasts of Maryland and North Carolina (United States), and the island nation of Aruba in the Caribbean. Useful data were available for analysing vertical and horizontal habitat use from 28 individuals. Time at liberty ranged from 10 to 181 d (mean 115, SD 53.3). Seasonal southerly fall migration routes were documented for fish released off the northeastern United States, while those released off Aruba remained in the Caribbean basin. Horizontal movements ranged from 228 to 8084 km (19–100 km d−1) based on light-level geolocation estimates using a sea surface temperature and bathymetry-corrected Kalman filter. Analyses included an evaluation of vertical movements using ΔT, the time spent at temperature relative to the uniform temperature surface layer. Movements included exploration of depths as great as 387 m and ambient temperatures as low as 7.8°C. However, the greatest proportion of time was spent in the upper 20 m of the water column for both day (50.8%) and night (81.6%), and time spent in water colder than 7°C below the uniform temperature surface layer was negligible. Overall, this group showed less variability in vertical movement, and less tolerance to colder temperatures compared with similar studies for blue marlin Makaira nigricans and sailfish Istiophorus platypterus. Values for ΔT are presented in tabular format to allow direct input into habitat standardization models used to estimate vertical distribution and population abundance. The large spatial dispersion and disparate tracks illustrated in the present study serve to underscore the complexity of white marlin behaviour and habitat use, and further emphasize the many challenges facing the management and conservation of this overexploited species.