Managing resistance to Bt crops in a genetically variable insect herbivore, Ostrinia nubilalis

To slow the resistance evolution of the European corn borer (ECB) to Cry proteins expressed in transgenic Bacillus thuringensis (Bt) corn, the United States Environmental Protection Agency (EPA) has adopted an insect resistance management (IRM) plan that relies on a “high dose/refuge” strategy. However, this IRM plan does not consider possible ecological differences between the two ECB pheromone races (E and Z). Using carbon isotope analysis, we found that unstructured (non-corn) refuges contribute more to E race (18%) than to Z race (4%) populations of ECB in upstate New York (USA). Furthermore, feeding on non-corn hosts is associated with decreased body mass and reduced fecundity. We also show that the geographic range of E-race ECB is restricted within the range of the Z race and that E-race ECB are increasingly dominant in regions with increasing non-corn habitat. While the proportion of E-race ECB developing in unstructured refuges is higher than previously assumed, low rates of unstructured refuge use by the Z race, evidence for reduced fecundity when reared on non-corn hosts, and complete sympatry within the E race range all argue against a relaxation of current IRM refuge standards in corn based on alternative-host use. We also discuss implications of this research for integrated pest management in vegetables and IRM in Bt cotton

Names and their meanings: A dual-process account of proper-name encoding and retrieval

The ability to pick out a unique entity with a proper name is an important component of human language. It has been a primary focus of research in the philosophy of language since the nineteenth century. Brain-based evidence has shed new light on this capacity, and an extensive literature indicates the involvement of distinct fronto-temporal and temporo-occipito-parietal association cortices in proper-name retrieval. However, comparatively few efforts have sought to explain how memory encoding processes lead to the later recruitment of these distinct regions at retrieval. Here, we provide a unified account of proper-name encoding and retrieval, reviewing evidence that socio-emotional and unitized encoding subserve the retrieval of proper names via anterior-temporal-prefrontal activations. Meanwhile, non-unitized item-item and item-context encoding support subsequent retrieval, largely dependent on the temporo-occipito-parietal cortex. We contend that this well-established divergence in encoding systems can explain how proper names are later retrieved from distinct neural structures. Furthermore, we explore how evidence reviewed here can inform a century-and-a-half-old debate about proper names and the meanings they pick out

In-flight wingtip folding: inspiration from the XB-70 Valkyrie

Wingip folding can be used to extend aircraft wingspan, allowing designers to take advantage of reduced induced drag whilst respecting ground operational limitations. Such devices can also be used in-flight for a variety of other benefits including load alleviation and flight control. The majority of in-flight folding research takes inspiration in past developments made on the XB-70 Valkyrie, which used the folding devices for stability and lift performance benefits. In this paper, the authors investigate the capabilities of the folding wingtip system and potential scaling to large civil aircraft. Manufacturing details are used to size the actuators whilst the aerodynamic loading acting on the wingtip hinges is found from flight test results. Dimensions and aerodynamic loading at cruise of a set of conventional civil aircraft wing are used to evaluate the scaling potential of the system for controlled in-flight folding. An estimate of the weight penalty due to the folding device is also given and compared to structural weight savings on the XB-70. The results presented herein help in the evaluation of conventional actuator limits for in-flight folding using arguably the most inspiring military example of wingtip folding so far

Analysis of Hold Times for Gaseous Fire Suppression Agents in Total Flooding Applications

Many of the clean agents currently used in total flooding fire suppression applications have vapor densities greater than ambient air. The denser agent-air mixture creates hydrostatic pressure differences causing flow of the mixture out of the enclosure as well as flow of ambient air in through leakage paths inherent in building construction. Hold time refers to the amount of time it takes for the concentration of the agent-air mixture to drop below a specified concentration at a designated height within the protected enclosure. In this study an experimental test enclosure was used to evaluate an analytical model of agent-air mixture leakage and to investigate the effects of different leakage areas on agent hold times. The analytical model, known as the descending interface model, demonstrated favorable agreement with experimental measurements for heights greater than one-half the height of the enclosure for the agent used in this investigation

Two-Photon Laser Scanning Microscopy of the Transverse-Axial Tubule System in Ventricular Cardiomyocytes from Failing and Non-Failing Human Hearts

Objective. The transverse-axial tubule system (TATS) of cardiomyocytes allows a spatially coordinated conversion of electrical excitation into an intracellular Ca2+ signal and consequently contraction. Previous reports have indicated alterations of structure and/or volume of the TATS in cardiac hypertrophy and failure, suggesting a contribution to the impairment of excitation contraction coupling. To test whether structural alterations are present in human heart failure, the TATS was visualized in myocytes from failing and non-failing human hearts. Methods and Results. In freshly isolated myocytes, the plasmalemmal membranes were labeled with Di-8-ANEPPS and imaged using two-photon excitation at 780 nm. Optical sections were taken every 300 nm through the cells. After deconvolution, the TATS was determined within the 3D data sets, revealing no significant difference in normalized surface area or volume. To rule out possible inhomogeneity in the arrangement of the TATS, Euclidian distance maps were plotted for every section, allowing to measure the closest distance between any cytosolic and any membrane point. There was a trend towards greater spacing in cells from failing hearts, without statistical significance. Conclusion. Only small changes, but no significant changes in the geometrical dimensions of the TATS were observed in cardiomyocytes from failing compared to non-failing human myocardium

Classical scrapie prions in ovine blood are associated with B lymphocytes and platelet-rich plasma

<p>Abstract</p> <p>Background</p> <p>Classical scrapie is a naturally occurring transmissible spongiform encephalopathy of sheep and goats characterized by cellular accumulation of abnormal isoforms of prion protein (PrP^Sc) in the central nervous system and the follicles of peripheral lymphoid tissues. Previous studies have shown that the whole blood and buffy coat blood fraction of scrapie infected sheep harbor prion infectivity. Although PrP^Schas been detected in peripheral blood mononuclear cells (PBMCs), plasma, and more recently within a subpopulation of B lymphocytes, the infectivity status of these cells and plasma in sheep remains unknown. Therefore, the objective of this study was to determine whether circulating PBMCs, B lymphocytes and platelets from classical scrapie infected sheep harbor prion infectivity using a sheep bioassay.</p> <p>Results</p> <p>Serial rectal mucosal biopsy and immunohistochemistry were used to detect preclinical infection in lambs transfused with whole blood or blood cell fractions from preclinical or clinical scrapie infected sheep. PrP^Scimmunolabeling was detected in antemortem rectal and postmortem lymphoid tissues from recipient lambs receiving PBMCs (15/15), CD72⁺B lymphocytes (3/3), CD21⁺B lymphocytes (3/3) or platelet-rich plasma (2/3) fractions. As expected, whole blood (11/13) and buffy coat (5/5) recipients showed positive PrP^Sclabeling in lymphoid follicles. However, at 549 days post-transfusion, PrP^Scwas not detected in rectal or other lymphoid tissues in three sheep receiving platelet-poor plasma fraction.</p> <p>Conclusions</p> <p>Prion infectivity was detected in circulating PBMCs, CD72⁺pan B lymphocytes, the CD21⁺subpopulation of B lymphocytes and platelet-rich plasma of classical scrapie infected sheep using a sheep bioassay. Combining platelets with B lymphocytes might enhance PrP^Scdetection levels in blood samples.</p

Towards Space-like Photometric Precision from the Ground with Beam-Shaping Diffusers

We demonstrate a path to hitherto unachievable differential photometric precisions from the ground, both in the optical and near-infrared (NIR), using custom-fabricated beam-shaping diffusers produced using specialized nanofabrication techniques. Such diffusers mold the focal plane image of a star into a broad and stable top-hat shape, minimizing photometric errors due to non-uniform pixel response, atmospheric seeing effects, imperfect guiding, and telescope-induced variable aberrations seen in defocusing. This PSF reshaping significantly increases the achievable dynamic range of our observations, increasing our observing efficiency and thus better averages over scintillation. Diffusers work in both collimated and converging beams. We present diffuser-assisted optical observations demonstrating $62^{+26}_{-16}$ppm precision in 30 minute bins on a nearby bright star 16-Cygni A (V=5.95) using the ARC 3.5m telescope---within a factor of $\sim$2 of Kepler's photometric precision on the same star. We also show a transit of WASP-85-Ab (V=11.2) and TRES-3b (V=12.4), where the residuals bin down to $180^{+66}_{-41}$ppm in 30 minute bins for WASP-85-Ab---a factor of $\sim$4 of the precision achieved by the K2 mission on this target---and to 101ppm for TRES-3b. In the NIR, where diffusers may provide even more significant improvements over the current state of the art, our preliminary tests have demonstrated $137^{+64}_{-36}$ppm precision for a $K_S =10.8$ star on the 200" Hale Telescope. These photometric precisions match or surpass the expected photometric precisions of TESS for the same magnitude range. This technology is inexpensive, scalable, easily adaptable, and can have an important and immediate impact on the observations of transits and secondary eclipses of exoplanets.Comment: Accepted for publication in ApJ. 30 pages, 20 figure

Transnational labor regulation, reification and commodification: A critical review

Why does scholarship on transnational labor regulation (TLR) consistently fails to search for improvements in working conditions, and instead devotes itself to relentless efforts for identifying administrative processes, semantics, and amalgamations of stakeholders? This article critiques TLR from a pro-worker perspective, through the philosophical work of Georg Lukács, and the concepts of reification and commodification. A set of theoretically grounded criteria is developed and these are applied against selected contemporary cases of TLR. In the totality that is capitalism, reification of social relations of production conceals completely the experiences of workers. In TLR, managerialist and process-oriented scholarship is dominant, verifiable outcomes and positive improvements in conditions of employment are not sought, and worse, meaningless procedures are celebrated as positive achievements

The water regime of dwarf planet (1) Ceres

The traditional view of minor bodies in the (inner) Solar System is that they are split into icy comets and rocky asteroids. However this has been challenged by recent results, such as the discovery of comets on asteroidal orbits in the outer asteroid belt (between Mars and Jupiter) and the detection of water ice frost on the surface of asteroid (24) Themis. The discovery of water ice on the surface of asteroids has profound implications for how the Solar System formed, and challenges our ideas about the stability of ice in the inner Solar System. The study of volatiles in the asteroid belt places strong constraints on the temperature and composition distribution in the proto-planetary disk,and on possible sources of terrestrial water, and strongly constrains formation models of the early Solar System