bluuebunny/crossref_metadata_2025 huggingface dataset:
The counterintuitive role of sexual selection in species maintenance and speciation
Authors: Servedio Maria R. , Bürger Reinhard
Published: May 2014

Significance

Sexual selection is generally considered to be an important force in the maintenance of species differentiation. Using population genetic models, we show that when isolated in its purest form of Fisherian sexual selection, sexual selection inhibits rather than assists species maintenance and speciation when isolated populations begin to exchange migrants. The stronger this type of sexual selection becomes, the more it erases any effects of local adaptation that drive trait divergence. Furthermore, if the strength of Fisherian sexual selection itself is allowed to evolve, sexual selection is lost. These results emphasize that additional complications have to be added to sexual selection scenarios for sexual selection to contribute to divergence; Fisherian sexual selection alone has the opposite effect.
Systematic determination of absolute absorption cross-section of individual carbon nanotubes
Authors: Liu Kaihui , Hong Xiaoping , Choi Sangkook , Jin Chenhao , Capaz Rodrigo B. , Kim Jihoon , Wang Wenlong , Bai Xuedong , Louie Steven G. , Wang Enge , Wang Feng
Published: May 2014

Significance

Determination of optical absorption cross-section is of central importance to understanding a material; however, its realization on individual nanostructures, such as carbon nanotubes, is experimentally challenging due to the small extinction signal using conventional transmission measurements. Here we develop a technique based on polarization manipulation to enhance the sensitivity of single-nanotube absorption spectroscopy by two orders of magnitude. We systematically determine absorption cross-section over broad spectral range at the single-tube level for more than 50 chirality-defined single-walled nanotubes. Our data reveals chirality-dependent one-dimensional photophysics through the behaviors of exciton oscillator strength and lifetime. We also establish an empirical formula to predict absorption spectrum of any nanotube, which provides the foundation to determine quantum efficiencies in important photoluminescence and photovoltaic processes.
Epitaxial superlattices with titanium nitride as a plasmonic component for optical hyperbolic metamaterials
Authors: Naik Gururaj V. , Saha Bivas , Liu Jing , Saber Sammy M. , Stach Eric A. , Irudayaraj Joseph M. K. , Sands Timothy D. , Shalaev Vladimir M. , Boltasseva Alexandra
Published: May 2014

Significance

Plasmonic and metamaterial devices require high-performance material building blocks, both plasmonic and dielectric, to be useful in any real-world application. Here, we develop both plasmonic and dielectric materials that can be grown epitaxially into ultrathin and ultrasmooth layers with sharp interfaces. We show that a superlattice consisting of titanium nitride as a plasmonic component behaves as an optical hyperbolic metamaterial and exhibits extremely high photonic density of states.
Use (and abuse) of expert elicitation in support of decision making for public policy
Authors: Morgan M. Granger
Published: May 2014

The elicitation of scientific and technical judgments from experts, in the form of subjective probability distributions, can be a valuable addition to other forms of evidence in support of public policy decision making. This paper explores when it is sensible to perform such elicitation and how that can best be done. A number of key issues are discussed, including topics on which there are, and are not, experts who have knowledge that provides a basis for making informed predictive judgments; the inadequacy of only using qualitative uncertainty language; the role of cognitive heuristics and of overconfidence; the choice of experts; the development, refinement, and iterative testing of elicitation protocols that are designed to help experts to consider systematically all relevant knowledge when they make their judgments; the treatment of uncertainty about model functional form; diversity of expert opinion; and when it does or does not make sense to combine judgments from different experts. Although it may be tempting to view expert elicitation as a low-cost, low-effort alternative to conducting serious research and analysis, it is neither. Rather, expert elicitation should build on and use the best available research and analysis and be undertaken only when, given those, the state of knowledge will remain insufficient to support timely informed assessment and decision making.
Limiting glutamate transmission in a
Vglut2
-expressing subpopulation of the subthalamic nucleus is sufficient to cause hyperlocomotion
Authors: Schweizer Nadine , Pupe Stéfano , Arvidsson Emma , Nordenankar Karin , Smith-Anttila Casey J. A. , Mahmoudi Souha , Andrén Anna , Dumas Sylvie , Rajagopalan Aparna , Lévesque Daniel , Leão Richardson N. , Wallén-Mackenzie Åsa
Published: May 2014

Significance

The subthalamic nucleus (STN) has an important role in locomotion, as evidenced by the successful use of high-frequency stimulation of this structure as treatment for Parkinson disease. There is considerable uncertainty, however, regarding the mechanism through which this effect is achieved. We identified a promoter diversity within this nucleus and observed a movement phenotype displayed as decreased latency in initiation of movement and increased locomotion in both horizontal and vertical planes as a consequence of blunting, but not eliminating, expression of
Vglut2
in the STN of mice. In contrast to various lesion and high-frequency-stimulation studies of the STN, our genetic approach leaves cognitive functions intact. Taken together, our findings could be important for advancing future therapeutic strategies.
Stabilization of graphene nanopore
Authors: Lee Jaekwang , Yang Zhiqing , Zhou Wu , Pennycook Stephen J. , Pantelides Sokrates T. , Chisholm Matthew F.
Published: May 2014

Significance

The key driving force for nanopore research has been the prospect of DNA sequencing, which requires small, thin pores for highest resolution. The length of the pore channel can be reduced to a single layer of atoms through the use of graphene. However, it is known that tiny holes in graphene are unstable against filling by carbon adatoms. Thus, the stabilization of such holes is a critical issue to be resolved to enable applications. We demonstrate the existence of stabilized holes in graphene and theoretical understanding of why they are stable. Our discoveries are a major step toward the development of robust and reliable graphene-based molecular translocation devices.
Chronological evidence fails to support claim of an isochronous widespread layer of cosmic impact indicators dated to 12,800 years ago
Authors: Meltzer David J. , Holliday Vance T. , Cannon Michael D. , Miller D. Shane
Published: May 2014

Significance

A key element underpinning the controversial hypothesis of a widely destructive extraterrestrial impact at the onset of the Younger Dryas is the claim that 29 sites across four continents yield impact indicators all dated to 12,800 ± 150 years ago. This claim can be rejected: only three of those sites are dated to this window of time. At the remainder, the supposed impact markers are undated or significantly older or younger than 12,800 years ago. Either there were many more impacts than supposed, including one as recently as 5 centuries ago, or, far more likely, these are not extraterrestrial impact markers.
RIP1 suppresses innate immune necrotic as well as apoptotic cell death during mammalian parturition
Authors: Kaiser William J. , Daley-Bauer Lisa P. , Thapa Roshan J. , Mandal Pratyusha , Berger Scott B. , Huang Chunzi , Sundararajan Aarthi , Guo Hongyan , Roback Linda , Speck Samuel H. , Bertin John , Gough Peter J. , Balachandran Siddharth , Mocarski Edward S.
Published: May 2014

Significance

The protein kinase receptor interacting protein 1 controls signaling via death receptors, Toll-like receptors, and retinoic acid-inducible gene 1-like receptors, dictating inflammatory outcomes as broad as cytokine activation and cell death. RIP1 makes a vital contribution during development, evident from the fact that RIP1-deficient mice die soon after birth. Here, we show that a kinase-independent function of RIP1 dampens the consequences of innate immune cell death. During parturition, RIP1 prevents the lethal consequences of RIP3-dependent necroptosis as well as caspase 8 (Casp8)-dependent apoptosis. In contrast to the RIP1-deficient phenotype, mice lacking a combination of RIP1, RIP3, and Casp8 are born and mature into viable, fertile, and immunocompetent adults. These results demonstrate the important protective role of RIP1 against physiologic and microbial death cues encountered at birth.
Site-specific genetic engineering of theAnopheles gambiaeY chromosome
Authors: Bernardini Federica , Galizi Roberto , Menichelli Miriam , Papathanos Philippos-Aris , Dritsou Vicky , Marois Eric , Crisanti Andrea , Windbichler Nikolai
Published: May 2014

Significance

Interfering with sex determination and male fertility are potentially powerful approaches for the genetic control of the human malaria vectorAnopheles gambiae.Despite this fact, the male-specific Y chromosome of this mosquito has remained largely unexplored, because of its repetitive, heterochromatic structure. Little is known about its ability to support gene transcription in different tissues and during gametogenesis, yet this information is crucial for understanding the function of this chromosome. We show, using a combination of knock-in and site-specific genetic engineering steps, how transgenes can be specifically introduced onto the Y chromosome. The Y-linked strains we have created provide the means to generate large single-sex populations and to establish male-exclusive genetic traits for the control of this important vector species.
Conflict translates environmental and social risk into business costs
Authors: Franks Daniel M. , Davis Rachel , Bebbington Anthony J. , Ali Saleem H. , Kemp Deanna , Scurrah Martin
Published: May 2014

Significance

In this report we investigate company–community conflict and its role in the regulation of sustainability performance in the extractive industries. We estimate the cost of conflict to companies and identify conflict as an important means through which environmental and social risks are translated into business costs and decision-making. The paper clarifies the relationship between the environmental and social risk experienced—and interpreted—by local communities, and the business risks experienced—and interpreted—by corporations. Findings reveal that, at least for the case of the extractive industries, these two types of risk can co-constitute each other. The central importance of corporate strategy and behavior for sustainability science is highlighted.
Interactional metadiscourse in young EFL learner writing
Authors: Hong Huaqing , Cao Feng
Published: May 2014

This study investigates how young English as a foreign language (EFL) learners from Chinese, Spanish, and Polish mother tongue backgrounds use interactional metadiscourse in descriptive and argumentative English essays by drawing data from the ICCI corpus. The quantitative and qualitative analyses show that (i) there are significant differences among the three groups of EFL learners in the use of boosters, attitude markers, self-mentions, and engagement markers; and (ii) there are significant differences between the descriptive essays and the argumentative essays in the use of hedges and self-mentions. Discussion of the results is related to intergroup homogeneity and heterogeneity in the use of metadiscourse and the influences of essay types as well as topics/prompts. Pedagogical implications are provided for teaching interactional metadiscursive resources to young EFL learners from different mother tongue backgrounds and in relation to descriptive and argumentative writing.
Objectively Assigning Species and Ages to Salmonid Length Data from Dual‐Frequency Identification Sonar
Authors: Gurney W. S. C. , Brennan Louise O. , Bacon P. J. , Whelan K. F. , O'Grady Martin , Dillane Eileen , McGinnity P.
Published: May 2014

Fishery managers need robust ways of objectively estimating the quantitative composition of fish stocks, by species and age‐class, from representative samples of populations. Dual‐frequency identification sonar data were used to first visually identify fish to a broad taxon (Salmonidae). Subsequently, kernel‐density estimations, based on calibrated size‐at‐age data for the possible component species, were used to assign sonar observations both to species (Atlantic Salmon Salmo salar or Brown Trout Salmo trutta) and age‐classes within species. The calculations are illustrated for alternative sets of calibration data. To obtain close and relevant fits, the approach fundamentally relies on having accurate and fully representative subcomponent distributions. Firmer inferences can be made if the component data sets correspond closely to the target information in both time and space. Given carefully chosen suites of component data, robust population composition estimates with narrow confidence intervals were obtained. General principles are stated, which indicate when such methods might work well or poorly.
Differentiation of Sympatric Arctic Char Morphotypes Using Major Histocompatibility Class II Genes
Authors: Conejeros Pablo , Phan Anna , Power Michael , O'Connell Michael , Alekseyev Sergey , Salinas Iván , Dixon Brian
Published: May 2014

Arctic CharSalvelinus alpinushave colonized northern postglacial lakes within the last few thousand years. Divergent populations have adapted to thrive in the prevailing oligotrophic environments and thus have developed morphotypes with different ecological behaviors. The morphotypes usually differ in size, morphology, coloration, feeding ecology, and/or habitat occupancy. Although morphotypes that have very divergent spawning seasons should become genetically segregated, genetic differentiation, in most cases, has been weak. Thus, results to date have suggested that Arctic Char morphotype separation has been driven largely by the environmentally mediated phenotypic plasticity of the species, with differentiation between morphotypes having commenced too recently to generate substantial genetic drift. Here we used the major histocompatibility (MH) class II genes in an attempt to isolate sympatric Arctic Char morphotypes known to be ecologically differentiated. These morphotypes are from postglacial lakes in both Siberia and eastern Canada, and differ in either diet, habitat occupancy, or both. The MH Class II allelic polymorphism was significantly different between morphotypes. This suggested there is differential heritable adaptation to the natural selection exerted by pathogens unique to each ecological niche within each lake.
Assessing the Long‐Term Reproductive Contribution of Stocked Fish to Largemouth Bass Populations
Authors: Nannini Michael A. , Diana Matthew J. , Claussen Julie E. , Philipp David P. , Wahl David H.
Published: May 2014

We evaluated the reproductive contribution of stocked Largemouth Bass Micropterus salmoides relative to resident populations. The reproductive contribution of stocked fish was determined using the MDH‐B2* allele as a genetic tag for fingerlings stocked into five study lakes. We first determined the relative survival of stocked fish by calculating the proportion of adults (which were clipped at stocking) in the population and compared it with initial survival the first fall after stocking. Stocked fish relative survival to adulthood varied among the five study lakes and was lower than initial survival after stocking. Once these stocked fish were mature, it was possible to assess their reproductive contribution to each population by comparing the prestocking frequencies of the MDH‐B2* allele with poststocking frequencies. Reproductive contribution of stocked fish was high in small lakes but relatively low in larger ones. Neither adult Largemouth Bass density nor prey density affected reproductive contribution of stocked fish. Based on the proportion of stocked adults in the populations, reproductive contribution of stocked fish was similar to that of wild fish. Our results indicate that reproductive contribution of stocked fish will depend on survival of stocked fish to maturity. The influence of stocked fish will likely persist in successive generations, and potential genetic effects on wild populations of Largemouth Bass should be taken into account when making stocking decisions.
Identifying Suitable Habitat for Chinook Salmon across a Large, Glaciated Watershed
Authors: Bidlack Allison L. , Benda Lee E. , Miewald Tom , Reeves Gordon H. , McMahan Gabriel
Published: May 2014

Ecosystem management requires information on habitat suitability across broad scales; however, comprehensive environmental surveys in remote areas are often impractical and expensive to carry out. Intrinsic Potential (IP) models provide a means to identify on a broad scale those portions of the landscape that can provide essential habitat for various freshwater fish species. These models are derived from watershed patterns and processes that are persistent and not readily affected by human activities. We developed an IP model for rearing habitat of Chinook Salmon throughout the Copper River watershed (63,000km2) in southcentral Alaska, utilizing digital elevation models, expert opinion, and field surveys. Our model uses three variables—mean annual flow, gradient, and glacial influence—and adequately predicts where probable habitat for juvenile Chinook Salmon occurs across this large landscape. This model can help resource managers map critical habitat for salmon throughout the Copper River watershed, direct field research to appropriate stream reaches, and assist managers in prioritizing restoration actions, such as culvert replacement. Intrinsic Potential modeling is broadly applicable to other salmonid species and geographies and may inform future work on the ecological impacts of climate change in polar and subpolar river systems.
Assessment of the Risks of Transgenic Fluorescent Ornamental Fishes to the United States Using the Fish Invasiveness Screening Kit (FISK)
Authors: Hill Jeffrey E. , Lawson Larry L. , Hardin Scott
Published: May 2014

Three species of transgenic fluorescent ornamental fish are commercially available to the public in the United States—Zebra Danio Danio rerio, Black Tetra Gymnocorymbus ternetzi, and Tiger Barb Systomus tetrazona. Despite qualitative assessments of the risks of these transgenic fishes by the U.S. Food and Drug Administration and two state agencies, critics argue that the risk assessment and approval processes were not transparent and that the results were never published or otherwise open to scientific scrutiny. We used an internationally recognized risk screening tool, the Fish Invasiveness Screening Kit (FISK), to provide a transparent, peer‐reviewed assessment for the conterminous United States. We found that the three transgenic fluorescent ornamental fishes in question represent a low risk of invasiveness. Any risk is limited to the warmer regions of the country. No potential for hybridization with native species, little history of invasiveness elsewhere, a lack of traits associated with persistence, and small body size coupled with predation‐enhancing fluorescence all indicate that the ability of these species to become established and have impacts is limited even in warm regions. Our finding of low risk is consistent with the results of unpublished, qualitative agency assessments using expert panels or in‐house expertise. The risk screens identified few data gaps, areas of important uncertainty, or potentially elevated risk levels, thus suggesting that there would be limited gain to committing resources to a full risk assessment. A low‐risk result further indicates little need for risk management actions in addition to those already being taken. Risk screens such as FISK can have high value for managers because they capture important elements of risk, providing vital information for assessment and management decisions with relatively small investments in time and funding.
Diel Littoral–Pelagic Movements by Juvenile Bluegills in a Small Lake
Authors: Shoup Daniel E. , Boswell Kevin M. , Wahl David H.
Published: May 2014

Diel littoral–pelagic migrations by juvenile fish have been suggested as a mechanism that optimizes the trade‐off between predation risk and foraging return in open‐water habitats. However, previous study designs have not been able to conclusively demonstrate this behavior in the field. We applied a horizontally oriented hydroacoustic transducer, set at the open‐water edge of littoral vegetation, to observe diel fish behavior during two summers in Ridge Lake, Illinois, where the fish community is dominated by Largemouth Bass Micropterus salmoides and Bluegills Lepomis macrochirus. Based on acoustically tracked targets, most juvenile fish moved away from vegetated habitat at night and towards vegetation during the day. A greater number of predator‐sized fish were observed in the open water during the day than at night and weak acoustic targets, most likely zooplankton, were more abundant in the open‐water habitat at night. Therefore, it is likely that the reduced predator abundance and/or activity combined with potentially greater food availability in the open‐water habitat prompted an offshore migration at night that was reversed after sunrise. Diel horizontal migration patterns could affect the timing and location of interspecific interactions in systems where they occur and further research is needed to determine whether diel migrations alter ecosystem function.
Fishing‐Related Stressors Inhibit Refuge‐Seeking Behavior in Released Subadult Great Barracuda
Authors: Brownscombe Jacob W. , Nowell Liane , Samson Emma , Danylchuk Andy J. , Cooke Steven J.
Published: May 2014

Fisheries interactions that result in the capture and release of fish can cause behavioral impairments that increase the risk of postrelease predation. Increased predation risk has been attributed to reduced swimming capabilities; however, the role of refuge (structural shelter) use is still poorly understood. We examined the effect of fishing‐related stressors on the ability of subadult Great Barracuda Sphyraena barracuda to attain refuge in an experimental wetland in Eleuthera, The Bahamas. Twenty‐two Great Barracuda were either treated as controls with minimum stress, chased to exhaustion, or chased to exhaustion and air exposed for 90s. Reflex action mortality predictors (RAMP) including ability to maintain equilibrium and bursting response were assessed prior to release at a standardized location. The prop roots of red mangrove Rhizophora mangle provided refuge about 5m from the release point. Great Barracuda were visually monitored for up to 30min postrelease to quantify behavior (resting, swimming, directional changes) and the time when refuge was reached. The RAMP scores increased with the degree of stressor, and fish in both fishing‐related stressor treatments took significantly longer to reach refuge than control fish, while air exposed fish took significantly longer than fish that were only chased. Prior to reaching refuge, fish exposed to fishing‐related stressors spent less time swimming, and changed directions more frequently than control fish, indicating that impaired locomotory capabilities and disorientation inhibited refuge use. The inability to find refuge after an acute stressor such as capture and release fisheries may be an important factor contributing to postrelease mortality for relevant species.
American Shad Migratory Behavior, Weight Loss, Survival, and Abundance in a North Carolina River following Dam Removals
Authors: Raabe Joshua K. , Hightower Joseph E.
Published: May 2014

Despite extensive management and research, populations of American Shad Alosa sapidissima have experienced prolonged declines, and uncertainty about the underlying mechanisms causing these declines remains. In the springs of 2007 through 2010, we used a resistance board weir and PIT technology to capture, tag, and track American Shad in the Little River, North Carolina, a tributary to the Neuse River with complete and partial removals of low‐head dams. Our objectives were to examine migratory behaviors and estimate weight loss, survival, and abundance during each spawning season. Males typically immigrated earlier than females and also used upstream habitat at a higher percentage, but otherwise exhibited relatively similar migratory patterns. Proportional weight loss displayed a strong positive relationship with both cumulative water temperature during residence time and number of days spent upstream, and to a lesser extent, minimum distance the fish traveled in the river. Surviving emigrating males lost up to 30% of their initial weight and females lost up to 50% of their initial weight, indicating there are potential survival thresholds. Survival for the spawning season was low and estimates ranged from 0.07 to 0.17; no distinct factors (e.g., sex, size, migration distance) that could contribute to survival were detected. Sampled and estimated American Shad abundance increased from 2007 through 2009, but was lower in 2010. Our study provides substantial new information about American Shad spawning that may aid restoration efforts.
Population Genetics of Arctic Grayling Distributed Across Large, Unobstructed River Systems
Authors: Reilly Jessica R. , Paszkowski Cynthia A. , Coltman David W.
Published: May 2014

We investigated the population genetics of Arctic Grayling Thymallus arcticus distributed throughout several connected river systems in Alberta, Canada. Broad‐ and fine‐scale population structure was examined by genotyping nine microsatellite loci in 1,116 Arctic Grayling captured from 40 sites in the Hay, Peace, and Athabasca River basins. Genetic diversity tended to decline from north to south (allelic richness versus latitude: Spearman's rank correlation rs = 0.793, P < 0.05); the lowest level of diversity was detected in a stocked population. We found significant genetic divergence between and within major river basins (overall genetic differentiation index FST [θST] = 0.13) and strong isolation‐by‐distance patterns in the Peace River basin (Mantel's r = 0.97, P < 0.001) and Athabasca River basin (Mantel's r = 0.95, P < 0.001). Evidence for gene flow among sites in neighboring rivers (i.e., 25–100km apart) was common; significant genetic differentiation tended to occur at the subbasin level. The spatial scale of differentiation for Arctic Grayling is intermediate to those reported for other sympatric salmonid species that differ in population size and degree of spawning site fidelity.
Variation in Minijack Rate among Hatchery Populations of Columbia River Basin Chinook Salmon
Authors: Harstad Deborah L. , Larsen Donald A. , Beckman Brian R.
Published: May 2014

In Columbia River spring and summer Chinook Salmon Oncorhynchus tshawytscha, age of male maturation ranges from age 1 (microjack), 2 (minijack), 3 (jack), to 4 or 5 (adult) years. The presence of minijacks has been noted in several experimental studies and documented for a few hatchery programs; but, a comprehensive survey of their occurrence in hatchery production programs has never been conducted. We measured the proportion of minijacks among males released from several spring‐ and summer‐run Chinook Salmon hatchery programs throughout the Columbia River basin among brood years 1999–2010. The hatcheries surveyed included both segregated (uses only hatchery‐origin spawners in broodstock) and integrated (includes some degree of natural‐origin spawners in broodstock) programs. Minijacks were found in all programs monitored, and rates varied approximately 10‐fold across release groups, ranging from 7.9% to 71.4% of males in spring Chinook Salmon programs and from 4.1% to 40.1% of males in summer Chinook Salmon programs. Cumulative growth (i.e., size at release) was found to be positively correlated with minijack rate, but for only the integrated Chinook Salmon programs. Domestication selection may have occurred in segregated spring Chinook Salmon programs, increasing the threshold size for maturation and lowering minijack rates. Elevated minijack rates in Chinook Salmon hatchery programs result in a direct reduction in both the number of male smolts released and potential adult males available for harvest and spawning.
Extraction of arbutin and its comparative content in branches, leaves, stems, and fruits of Japanese pear Pyrus pyrifolia cv. Kousui
Authors: Sasaki Chizuru , Ichitani Masaki , Kunimoto Ko-Ki , Asada Chikako , Nakamura Yoshitoshi
Published: May 2014

Arbutin is a tyrosinase inhibitor and is extensively used as a human skin-whitening agent. This study investigated the optimum conditions for extracting arbutin by ultrasonic homogenization from discarded branches pruned from Japanese pear (Pyrus pyrifolia cv. Kousui) trees. The arbutin content was measured in the branches and also in the leaves, stems, fruit peel, and fruit flesh.
Acid-sensing ion channels in mouse olfactory bulb M/T neurons
Authors: Li Ming-Hua , Liu Selina Qiuying , Inoue Koichi , Lan Jinquan , Simon Roger P. , Xiong Zhi-Gang
Published: May 2014

The olfactory bulb contains the first synaptic relay in the olfactory pathway, the sensory system in which odorants are detected enabling these chemical stimuli to be transformed into electrical signals and, ultimately, the perception of odor. Acid-sensing ion channels (ASICs), a family of proton-gated cation channels, are widely expressed in neurons of the central nervous system. However, no direct electrophysiological and pharmacological characterizations of ASICs in olfactory bulb neurons have been described. Using a combination of whole-cell patch-clamp recordings and biochemical and molecular biological analyses, we demonstrated that functional ASICs exist in mouse olfactory bulb mitral/tufted (M/T) neurons and mainly consist of homomeric ASIC1a and heteromeric ASIC1a/2a channels. ASIC activation depolarized cultured M/T neurons and increased their intracellular calcium concentration. Thus, ASIC activation may play an important role in normal olfactory function.
Adaptive potentiation in rod photoreceptors after light exposure
Authors: McKeown Alex S. , Kraft Timothy W.
Published: May 2014

Photoreceptors adapt to changes in illumination by altering transduction kinetics and sensitivity, thereby extending their working range. We describe a previously unknown form of rod photoreceptor adaptation in wild-type (WT) mice that manifests as a potentiation of the light response after periods of conditioning light exposure. We characterize the stimulus conditions that evoke this graded hypersensitivity and examine the molecular mechanisms of adaptation underlying the phenomenon. After exposure to periods of saturating illumination, rods show a 10–35% increase in circulating dark current, an adaptive potentiation (AP) to light exposure. This potentiation grows as exposure to light is extended up to 3 min and decreases with longer exposures. Cells return to their initial dark-adapted sensitivity with a time constant of recovery of ∼7 s. Halving the extracellular Mg concentration prolongs the adaptation, increasing the time constant of recovery to 13.3 s, but does not affect the magnitude of potentiation. In rods lacking guanylate cyclase activating proteins 1 and 2 (GCAP−/−), AP is more than doubled compared with WT rods, and halving the extracellular Mg concentration does not affect the recovery time constant. Rods from a mouse expressing cyclic nucleotide–gated channels incapable of binding calmodulin also showed a marked increase in the amplitude of AP. Application of an insulin-like growth factor-1 receptor (IGF-1R) kinase inhibitor (Tyrphostin AG1024) blocked AP, whereas application of an insulin receptor kinase inhibitor (HNMPA(AM)3) failed to do so. A broad-acting tyrosine phosphatase inhibitor (orthovanadate) also blocked AP. Our findings identify a unique form of adaptation in photoreceptors, so that they show transient hypersensitivity to light, and are consistent with a model in which light history, acting via the IGF-1R, can increase the sensitivity of rod photoreceptors, whereas the photocurrent overshoot is regulated by Ca-calmodulin and Ca2+/Mg2+-sensitive GCAPs.
Generalization of the Proca Action
Authors: Heisenberg Lavinia
Published: May 2014

We consider the Lagrangian of a vector field with derivative self-interactions with a priori arbitrary coefficients. Starting with a flat space-time we show that for a special choice of the coefficients of the self-interactions the ghost-like pathologies disappear. This constitutes the Galileon-type generalization of the Proca action with only three propagating physical degrees of freedom. The longitudinal mode of the vector field is associated to the usual Galileon interactions for a specific choice of the overall functions. In difference to a scalar Galileon theory, the generalized Proca field has more free parameters. We then extend this analysis to a curved background. The resulting theory is the Horndeski Proca action with second order equations of motion on curved space-times.
Quasi-convex free polynomials
Authors: Balasubramanian S. , McCullough S.
Published: May 2014

LetR⟨x⟩\mathbb R\langle x \rangledenote the ring of polynomials inggfreely noncommuting variablesx=(x1,…,xg)x=(x_1,\dots ,x_g). There is a natural involution∗*onR⟨x⟩\mathbb R\langle x \rangledetermined byxj∗=xjx_j^*=x_jand(pq)∗=q∗p∗(pq)^*=q^* p^*, and a free polynomialp∈R⟨x⟩p\in \mathbb R\langle x \rangleis symmetric if it is invariant under this involution. IfX=(X1,…,Xg)X=(X_1,\dots ,X_g)is aggtuple of symmetricn×nn\times nmatrices, then the evaluationp(X)p(X)is naturally defined and furtherp∗(X)=p(X)∗p^*(X)=p(X)^*. In particular, ifppis symmetric, thenp(X)∗=p(X)p(X)^*=p(X). The main result of this article says ifppis symmetric,p(0)=0p(0)=0and for eachnnand each symmetric positive definiten×nn\times nmatrixAAthe set{X:A−p(X)≻0}\{X:A-p(X)\succ 0\}is convex, thenpphas degree at most two and is itself convex, or−p-pis a hermitian sum of squares.
Erratum: “On the computation of local components of a newform”
Authors: Loeffler David , Weinstein Jared
Published: May 2014

It has been brought to our attention that there is an error in Section 4 of our article, On the computation of local components of a newform, Math. Comp. 81, 2012. We briefly explain how this error can be corrected.
Modelling multiple fishing gear efficiencies and abundance for aggregated populations using fishery or survey data
Authors: Zhou Shijie , Klaer Neil L. , Daley Ross M. , Zhu Zhengyuan , Fuller Michael , Smith Anthony D. M.
Published: May 2014

Fish and wildlife often exhibit an aggregated distribution pattern, whereas local abundance changes constantly due to movement. Estimating population density or size and survey detectability (i.e. gear efficiency in a fishery) for such elusive species is technically challenging. We extend abundance and detectability (N-mixture) methods to deal with this difficult situation, particularly for application to fish populations where gear efficiency is almost never equal to one. The method involves a mixture of statistical models (negative binomial, Poisson, and binomial functions) at two spatial scales: between-cell and within-cell. The innovation in this approach is to use more than one fishing gear with different efficiencies to simultaneously catch (sample) the same population in each cell at the same time-step. We carried out computer simulations on a range of scenarios and estimated the relevant parameters using a Bayesian technique. We then applied the method to a demersal fish species, tiger flathead, to demonstrate its utility. Simulation results indicated that the models can disentangle the confounding parameters in gear efficiency and abundance, and the accuracy generally increases as sample size increases. A joint negative binomial–Poisson model using multiple gears gives the best fit to tiger flathead catch data, while a single gear yields unrealistic results. This cross-sampling method can evaluate gear efficiency cost effectively using existing fishery catch data or survey data. More importantly, it provides a means for estimating gear efficiency for gear types (e.g. gillnets, traps, hook and line, etc.) that are extremely difficult to study using field experiments.
Pleiotropic functions of TNF-α in the regulation of the intestinal epithelial response to inflammation
Authors: Leppkes Moritz , Roulis Manolis , Neurath Markus F. , Kollias George , Becker Christoph
Published: May 2014

An important function of intestinal epithelial cells (IECs) is to maintain the integrity of the mucosal barrier. Inflammation challenges the integrity of the mucosal barrier and the intestinal epithelium needs to adapt to a multitude of signals in order to perform the complex process of maintenance and restitution of its barrier function. Dysfunctions in epithelial barrier integrity and restoration contribute to the pathogenesis of inflammatory bowel diseases (IBDs) such as Crohn’s disease and ulcerative colitis. Mucosal healing has developed to a significant treatment goal in IBD. In this review, we would like to highlight physiologic and pathologic adaptations of the intestinal epithelium to inflammation, exemplified by its responses to TNF-α. A large body of literature exists that highlights the diverse effects of this cytokine on IECs. TNF-α modulates intestinal mucus secretion and constitution. TNF-α stimulation modulates paracellular flow via tight junctional control. TNF-α induces intracellular signaling cascades that determine significant cell fate decisions such as survival, cell death or proliferation. TNF-α impacts epithelial wound healing in ErbB- and Wnt-dependent pathways while also importantly guiding immune cell attraction and function. We selected important studies from recent years with a focus on functional in vivo data providing crucial insights into the complex process of intestinal homeostasis.
Tryptophan Requirement of the Enterally Fed Term Infant in the First Month of Life
Authors: Huang Lisha , Hogewind‐Schoonenboom Jacomine E. , Zhu Li , Kraaijenga Juliette V.S. , van Haren Nicky P.C. , Voortman Gardi J. , Schierbeek Henk , Twisk Jos W.R. , Huang Ying , Chen Chao , van Goudoever Johannes B.
Published: May 2014

Objectives:

Tryptophan not only is an amino acid essential to protein synthesis but also serves as a precursor in 2 important metabolic pathways: the serotonin and the kynurenine pathways. Tryptophan is related to sleeping patterns. The objective of the present study was to determine the tryptophan requirement of term infants using the indicator amino acid oxidation (IAAO) method with L‐[1‐13C]phenylalanine as the indicator.

Methods:

Enterally fed infants were randomly assigned to tryptophan intakes ranging from 0.5 to 73 mg · kg−1 · day−1 as part of an elemental diet. After 1‐day adaptation to the test diet, [13C]bicarbonate and L‐[1‐13C]phenylalanine tracers were given enterally. Breath samples were collected at baseline and during isotopic plateaus. The mean tryptophan requirement was determined by using the biphasic linear regression crossover analysis on the fraction of 13CO2 recovery from L‐[1‐13C]phenylalanine oxidation (F13CO2). Data are presented as mean ± standard deviation.

Results:

A total of 30 term neonates (gestational age 39 ± 1 weeks) were studied at 9 ± 4 days. F13CO2 decreased until a tryptophan intake of 15 mg · kg−1 · day−1; additional increases in tryptophan intake did not affect F13CO2. Mean requirement was determined to be 15 mg · kg−1 · day−1.

Conclusions:

The mean tryptophan requirement for elemental formula‐fed term infants is 15 mg · kg−1 · day−1. This requirement is lower than the present recommended intake of 29 mg · kg−1 · day−1, which is based on the average intake of a breastfed infant.
The application of transcriptional blood signatures to enhance our understanding of the host response to infection: the example of tuberculosis
Authors: Blankley Simon , Berry Matthew Paul Reddoch , Graham Christine M. , Bloom Chloe I. , Lipman Marc , O'Garra Anne
Published: May 2014

Despite advances in antimicrobials, vaccination and public health measures, infectious diseases remain a leading cause of morbidity and mortality worldwide. With the increase in antimicrobial resistance and the emergence of new pathogens, there remains a need for new and more accurate diagnostics, the ability to monitor adequate treatment response as well as the ability to predict prognosis for an individual. Transcriptional approaches using blood signatures have enabled a better understanding of the host response to diseases, leading not only to new avenues of basic research, but also to the identification of potential biomarkers for use in diagnosis, prognosis and treatment monitoring.
The contribution of vaccination to global health: past, present and future
Authors: Greenwood Brian
Published: May 2014

Vaccination has made an enormous contribution to global health. Two major infections, smallpox and rinderpest, have been eradicated. Global coverage of vaccination against many important infectious diseases of childhood has been enhanced dramatically since the creation of WHO's Expanded Programme of Immunization in 1974 and of the Global Alliance for Vaccination and Immunization in 2000. Polio has almost been eradicated and success in controlling measles makes this infection another potential target for eradication. Despite these successes, approximately 6.6 million children still die each year and about a half of these deaths are caused by infections, including pneumonia and diarrhoea, which could be prevented by vaccination. Enhanced deployment of recently developed pneumococcal conjugate and rotavirus vaccines should, therefore, result in a further decline in childhood mortality. Development of vaccines against more complex infections, such as malaria, tuberculosis and HIV, has been challenging and achievements so far have been modest. Final success against these infections may require combination vaccinations, each component stimulating a different arm of the immune system. In the longer term, vaccines are likely to be used to prevent or modulate the course of some non-infectious diseases. Progress has already been made with therapeutic cancer vaccines and future potential targets include addiction, diabetes, hypertension and Alzheimer's disease.
The contribution of mass drug administration to global health: past, present and future
Authors: Webster Joanne P. , Molyneux David H. , Hotez Peter J. , Fenwick Alan
Published: May 2014

Mass drug administration (MDA) is a means of delivering safe and inexpensive essential medicines based on the principles of preventive chemotherapy, where populations or sub-populations are offered treatment without individual diagnosis. High-coverage MDA in endemic areas aims to prevent and alleviate symptoms and morbidity on the one hand and can reduce transmission on the other, together improving global health. MDA is the recommended strategy of the World Health Organisation to control or eliminate several neglected tropical diseases (NTDs). More than 700 million people now receive these essential NTD medicines annually. The combined cost of integrated NTD MDA has been calculated to be in the order of $0.50 per person per year. Activities have recently been expanded due, in part, to the proposed attempt to eliminate certain NTDs in the coming two decades. More than 1.9 billion people need to receive MDA annually across several years if these targets are to be met. Such extensive coverage will require additional avenues of financial support, expanded monitoring and evaluation focusing on impact and drug efficacy, as well as new diagnostic tools and social science strategies to encourage adherence. MDA is a means to help reduce the burden of disease, and hence poverty, among the poorest sector of populations. It has already made significant improvements to global health and productivity and has the potential for further successes, particularly where incorporated into sanitation and education programmes. However logistical, financial and biological challenges remain.
The coverage and frequency of mass drug administration required to eliminate persistent transmission of soil-transmitted helminths
Authors: Anderson Roy , Truscott James , Hollingsworth T. Deirdre
Published: May 2014

A combination of methods, including mathematical model construction, demographic plus epidemiological data analysis and parameter estimation, are used to examine whether mass drug administration (MDA) alone can eliminate the transmission of soil-transmitted helminths (STHs). Numerical analyses suggest that in all but low transmission settings (as defined by the magnitude of the basic reproductive number,R0), the treatment of pre-school-aged children (pre-SAC) and school-aged children (SAC) is unlikely to drive transmission to a level where the parasites cannot persist. High levels of coverage (defined as the fraction of an age group effectively treated) are required in pre-SAC, SAC and adults, if MDA is to drive the parasite below the breakpoint under which transmission is eliminated. Long-term solutions to controlling helminth infections lie in concomitantly improving the quality of the water supply, sanitation and hygiene (WASH). MDA, however, is a very cost-effective tool in long-term control given that most drugs are donated free by the pharmaceutical industry for poor regions of the world. WASH interventions, by lowering the basic reproductive number, can facilitate the ability of MDA to interrupt transmission.
Litoreibacter
ascidiaceicola sp. nov., isolated from the golden sea squirt Halocynthia
aurantium
Authors: Kim Young-Ok , Park Sooyeon , Nam Bo-Hye , Park Ji-Min , Kim Dong-Gyun , Yoon Jung-Hoon
Published: May 2014

A Gram-stain-negative, aerobic, non-motile and coccoid, ovoid or rod-shaped bacterial strain, designated RSS4-C1T, was isolated from a golden sea squirt (Halocynthia
aurantium) collected from the East Sea, South Korea. The novel strain grew optimally at 25 °C, at pH 7.0–8.0 and in the presence of 1.0–3.0 % (w/v) NaCl. Phylogenetic trees based on 16S rRNA gene sequences revealed that strain RSS4-C1T fell within the clade comprising the type strains of species of the genus

Litoreibacter

. Strain RSS4-C1T exhibited the highest 16S rRNA gene sequence similarity (99.6 %) to the type strain of

Litoreibacter albidus

and sequence similarities of 96.5–98.5 % to type strains of other recognized species of the genus

Litoreibacter

. Strain RSS4-C1T contained Q-10 as the predominant ubiquinone and C18 : 1ω7c and 11-methyl-C18 : 1ω7c as the major fatty acids. The major polar lipids of strain RSS4-C1T were phosphatidylcholine, phosphatidylglycerol, phosphatidylethanolamine, one unidentified lipid and one unidentified aminolipid. The DNA G+C content of strain RSS4-C1T was 58.0 mol% and its DNA–DNA relatedness values with type strains of four species of the genus

Litoreibacter

were 21–34 %. The differential phenotypic properties, together with phylogenetic and genetic distinctiveness, revealed that strain RSS4-C1T is distinct from other species of the genus

Litoreibacter

. On the basis of the data presented, strain RSS4-C1T is considered to represent a novel species of the genus

Litoreibacter

, for which the name Litoreibacter
ascidiaceicola sp. nov. is proposed. The type strain is RSS4-C1T ( = KCTC 42050T = CECT 8539T).