bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling climate-change effects on Australian and Pacific aquatic ecosystems: a review of analytical tools and management implications
Authors: Plagányi Éva E. , Bell Johann D. , Bustamante Rodrigo H. , Dambacher Jeffrey M. , Dennis Darren M. , Dichmont Cathy M. , Dutra Leo X. C. , Fulton Elizabeth A. , Hobday Alistair J. , Ingrid van Putten E. , Smith Franz , Smith Anthony D. M. , Zhou Shijie
Published: September 2011

Climate change presents significant challenges to modelling and managing aquatic resources. Equilibrium assumptions common in many modelling approaches need to be replaced by formulations that allow for changing baselines and integration of ongoing changes and adaptations by species, ecosystems and humans. As ecosystems change, so will the ways humans use, monitor and manage them. Consequently, adaptive management loops and supporting tools deserve more prominence in the management toolbox. Models are critical tools for providing an early understanding of the challenges to be faced by integrating observations and examining possible solutions. We review modelling tools currently available to incorporate the effect of climate change on marine and freshwater ecosystems, and the implications for management of natural resources. System non-linearity can confound interpretations and hence adaptive management responses are needed that are robust to unexpected outcomes. An improvement in the ability to model the effects of climate change from a social and economic perspective is necessary. The outputs from ‘end-to-end’ and socio-ecological models can potentially inform planning, in both Australia and the Pacific region, about how best to build resilience to climate change. In this context, the importance of well directed data-collection programs is also emphasised. Lessons from this region, which is advanced with regard to modelling approaches, can guide increased use of models to test options for managing aquatic resources worldwide.
Climate change and its implications for Australia's freshwater fish
Authors: Morrongiello John R. , Beatty Stephen J. , Bennett James C. , Crook David A. , Ikedife David N. E. N. , Kennard Mark J. , Kerezsy Adam , Lintermans Mark , McNeil Dale G. , Pusey Bradley J. , Rayner Thomas
Published: September 2011

Freshwater environments and their fishes are particularly vulnerable to climate change because the persistence and quality of aquatic habitat depend heavily on climatic and hydrologic regimes. In Australia, projections indicate that the rate and magnitude of climate change will vary across the continent. We review the likely effects of these changes on Australian freshwater fishes across geographic regions encompassing a diversity of habitats and climatic variability. Commonalities in the predicted implications of climate change on fish included habitat loss and fragmentation, surpassing of physiological tolerances and spread of alien species. Existing anthropogenic stressors in more developed regions are likely to compound these impacts because of the already reduced resilience of fish assemblages. Many Australian freshwater fish species are adapted to variable or unpredictable flow conditions and, in some cases, this evolutionary history may confer resistance or resilience to the impacts of climate change. However, the rate and magnitude of projected change will outpace the adaptive capacities of many species. Climate change therefore seriously threatens the persistence of many of Australia’s freshwater fish species, especially of those with limited ranges or specific habitat requirements, or of those that are already occurring close to physiological tolerance limits. Human responses to climate change should be proactive and focus on maintaining population resilience through the protection of habitat, mitigation of current anthropogenic stressors, adequate planning and provisioning of environmental flows and the consideration of more interventionist options such as managed translocations.
Potential effects of climate change on Australian estuaries and fish utilising estuaries: a review
Authors: Gillanders Bronwyn M. , Elsdon Travis S. , Halliday Ian A. , Jenkins Gregory P. , Robins Julie B. , Valesini Fiona J.
Published: September 2011

Estuaries are especially vulnerable to the impacts of climate change because changes in climatic and hydrologic variables that influence freshwater and marine systems will also affect estuaries. We review potential impacts of climate change on Australian estuaries and their fish. Geographic differences are likely because southern Australian climates are predicted to become warmer and drier, whereas northern regions may see increased precipitation. Environmental factors, including salinity gradients, suspended sediment, dissolved oxygen and nutrient concentrations, will be influenced by changing freshwater input and other climate variables. Potential impacts will vary depending on the geomorphology of the estuary and the level of build-up of sand bars across estuarine entrances. Changes to estuarine fish assemblages will depend on associated changes to salinity and estuarine-mouth morphology. Marine migrants may be severely affected by closure of estuarine mouths, depending on whether species ‘must’ use estuarine habitat and the level of migratory v. resident individuals. Depending on how fish in coastal waters locate estuaries, there may be reduced cues associated with estuarine mouths, particularly in southern Australia, potentially influencing abundance. In summary, climate change is expected to have major consequences for Australian estuaries and associated fish, although the nature of impacts will show significant regional variation.
Spatial segregation of BDNF transcripts enables BDNF to differentially shape distinct dendritic compartments
Authors: Baj Gabriele , Leone Emiliano , Chao Moses V. , Tongiorgi Enrico
Published: September 2011

BDNF is produced from many transcripts that display distinct subcellular localization, suggesting that spatially restricted effects occur as a function of genetic and physiological regulation. Different BDNF 5′ splice variants give a restricted localization in the cell body or the proximal and distal compartments of dendrites; however, the functional consequences are not known. Silencing individual endogenous transcripts or overexpressing BDNF-GFP transcripts in cultured neurons demonstrated that whereas some transcripts (1 and 4) selectively affected proximal dendrites, others (2C and 6) affected distal dendrites. Moreover, segregation of BDNF transcripts resulted in a highly selective activation of the BDNF TrkB receptor. These studies indicate that spatial segregation of BDNF transcripts enables BDNF to differentially shape distinct dendritic compartments.
Calreticulin chaperones regulate functional expression of vomeronasal type 2 pheromone receptors
Authors: Dey Sandeepa , Matsunami Hiroaki
Published: September 2011

A variety of social behaviors like intermale aggression, fear, and mating rituals are important for sustenance of a species. In mice, these behaviors have been implicated to be mediated by peptide pheromones that are sensed by a class of G protein-coupled receptors, vomeronasal receptor type 2 (V2Rs), expressed in the pheromone detecting vomeronasal organ. Matching V2Rs with their cognate ligands is required to learn what receptors the biologically relevant pheromones are acting on. However, this feat has been greatly limited by the unavailability of appropriate heterologous tools commonly used to study ligand receptor specificity, because this family of receptors fails to traffic to the surface of heterologous cells. Here we show that calreticulin, a housekeeping chaperone commonly expressed in most eukaryotic cells, is sparsely expressed in the vomeronasal sensory neurons (VSNs). Correspondingly, knockdown of calreticulin in commonly available cell lines enables V2Rs to efficiently target to the cell membrane. Using this knowledge, we have now been able to successfully surface express receptors and functionally identify cognate ligands. Additionally, calreticulin4, a homolog of calreticulin shows restricted and enriched expression in the VSNs. Interestingly, in heterologous cells, calreticulin4 does not inhibit surface expression of V2Rs and can in part carry out functions of calreticulin. On the basis of our data, we postulate that V2Rs may use a unique trafficking mechanism whereby an important and more commonly expressed chaperone is deleterious for membrane export and is replaced by a functionally equivalent homolog that does not inhibit export while carrying out its functions.
Analysis of a
Drosophila
amplicon in follicle cells highlights the diversity of metazoan replication origins
Authors: Kim Jane C. , Orr-Weaver Terry L.
Published: September 2011

To investigate the properties of metazoan replication origins, recent studies in cell culture have adopted the strategy of identifying origins using genome-wide approaches and assessing correlations with such features as transcription and histone modifications.
Drosophila
amplicon in follicle cells (
DAFCs
), genomic regions that undergo repeated rounds of DNA replication to increase DNA copy number, serve as powerful in vivo model replicons. Because there are six
DAFCs
, compared with thousands of origins activated in the typical S phase, close molecular characterization of all
DAFCs
is possible. To determine the extent to which the six
DAFCs
are different or similar, we investigated the developmental and replication properties of the newly identified
DAFC-34B
.
DAFC-34B
contains two genes expressed in follicle cells, although the timing and spatial patterns of expression suggest that amplification is not a strategy to promote high expression at this locus. Like the previously characterized
DAFC-62D
,
DAFC-34B
displays origin activation at two separate stages of development. However, unlike
DAFC-62D
, amplification at the later stage is not transcription-dependent. We mapped the
DAFC-34B
amplification origin to 1 kb by nascent strand analysis and delineated
cis
requirements for origin activation, finding that a 6-kb region, but not the 1-kb origin alone, is sufficient for amplification. We analyzed the developmental localization of the origin recognition complex (ORC) and the minichromosome maintenance (MCM)2-7 complex, the replicative helicase. Intriguingly, the final round of origin activation at
DAFC-34B
occurs in the absence of detectable ORC, although MCMs are present, suggesting a new amplification initiation mechanism.
Richard Pipes in Soviet Publications: Implications of the Reactions of Soviet Printed Media to Richard Pipes's Work on Soviet Nationalities
Authors: Bilinsky Yaroslav
Published: September 2011

This essay in political historiography aims to show how Professor Richard Pipes's monumental work on Soviet nationalities has been received by Soviet publications. It is more limited in scope than the main title connotes, since it does not deal with Soviet reactions to the totality of Pipes's scholarly work, only to an early but important part of his opus; nor is it concerned with Soviet attacks on Pipes's government service. The printed media surveyed include mostly articles in professional journals and books. Working through the Current Digest of the Soviet Press, this writer has tried to locate Soviet newspaper articles dealing with Pipes's work on nationalities, but has had no success. This is less of a shortcoming than it first appears, because even articles in Soviet scholarly journals, even books undergirded with an impressive scholarly apparatus, insofar as they deal with such a sensitive topic as the partial failure to solve the nationality problem, cannot but follow the party's policies of the moment. Apolitical historiography in the Soviet Union simply does not exist.
The Press and Soviet Nationalities: The Party Resolution of 1975 and its Implementation
Authors: Szporluk Roman
Published: September 2011

Many scholars have written on Soviet nationality policies, including language policies. This article does not aspire to add to the general literature of the subject. Rather, it is concerned with one particular decision of the Soviet leadership regarding the periodical press. All information presented here is derived from Soviet sources. Those sources include, first of all, a periodical that is not generally known in the West, which may explain why the decision in question was not noted by foreign observers when it was announced in that particular periodical.
Bulgarian Nationalities Policy in Occupied Thrace and Aegean Macedonia
Authors: Hoppe Hans-Joachim
Published: September 2011

After the outbreak of World War II, the Bulgarian government pursued a policy of non-alignment. In the fall of 1940 it rejected plans for a combined Italian-Bulgarian attack against Greece. And when Italy alone invaded Greece, Bulgaria facilitated Greek resistance by her own passivity. When Germany called on Bulgaria to enter the Tripartite Pact and make its territory available for a German attack against Greece, the Bulgarian leadership succeeded in retarding the talks. At the same time, the Soviet Union, Germany's Balkan rival, tried to entice Bulgaria into concluding a pact of mutual assistance by offering the whole of western and eastern Thrace at the expense of both Turkey and Greece. Bulgaria refused, and on 1 March 1941 joined the alliance with Germany in hope of territorial gains. It took this step only when it seemed unavoidable.
The Karaite Community in Interwar Poland
Authors: Green Warren
Published: September 2011

The Karaites are a schismatic Jewish sect which severed itself from the Babylonian Jewish community in the eighth century of the Common Era. The Karaites contended that the Rabbinites, the adherents to the Rabbinic tradition of Judaism, had perverted the Torah (Pentateuch) by superseding it with the Talmud (the compendium of the oral tradition of Jewish law). As a result of this theological argument, the Karaites adopted a fundamentalist approach to scriptural exegesis. The two groups differed in such areas as: observance of religious laws, the order of prayers, dietary laws and determining the dates of Jewish holidays.
Jews and Peasant in Interwar Hungary
Authors: McCagg William O.
Published: September 2011

Hungary was one of three Eastern European countries which, between the great wars, contained both large peasant and Jewish populations. The others were Poland and Rumania, and in both the record is clear enough: the peasants can be said to have disliked the Jews. In Hungary, however things were not so simple.
War Crimes Evidence from Soviet Latvia
Authors: Ezergailis Andrew
Published: September 2011

One of the blank areas of Latvian history is the period of German occupation 1941-45. Especially obscure are the crimes against humanity and war crimes committied during that period. It is so in the West among the emigrés, and the situation is no better in Soviet Latvia. It is a taboo topic all around—the Soviets have made it taboo by sitting on the evidence, the Latvians abroad have made it taboo for their own convoluted reasons.
Bibliographic Article: Baltic Émigré Publishing and Scholarship in the Western World
Authors: Crowe David
Published: September 2011

The Soviet absorption of Estonia, Latvia, and Lithuania during World War II caused hundreds of thousands of Baltic immigrants to come to the West, where they established strong, viable ethnic communities, often in league with groups that had left the region earlier. At first, Baltic publishing and publications centered almost exclusively on nationalistic themes that decried the loss of Baltic independence and attacked the Soviet Union for its role in this matter. In time, however, serious scholarship began to replace some of the passionate outpourings, and a strong, academic field of Baltic scholarship emerged in the West that dealt with all aspects of Baltic history, politics, culture, language, and other matters, regardless of its political or nationalistic implications. Over the past sixteen years, these efforts have produced a new body of Baltic publishing that has revived a strong interest in Baltic studies and has insured that regardless of the continued Soviet-domination of the region, the study of the culture and history of Estonia, Latvia, and Lithuania will remain a set fixture in Western scholarship on Eastern Europe.
Introduction: Reflections on Baltic Exceptionalism
Authors: Penikis Andrejs
Published: September 2011

On October 20, 1989 the Harriman Institute's Nationalities and Siberian Studies Program of Columbia University sponsored a panel discussion entitled, “The Baltic Republics Fifty Years After the Molotov-Ribbentrop Pact.” The panel, consisting of Dr. Allen Lynch, Dr. Stephan Kux, Mr. Jenik Radon and Mr. William Hough, analyzed the current situation in Estonia, Latvia and Lithuania as well as in the other republics from a variety of perspectives, and debated the motivations and appropriateness of the response of the Western powers to the growing strength of the various independence movements in the Baltic republics. The following edited transcript of those proceedings points up the complex and contentious nature of the status of the Baltic republics in the era of Gorbachev, in both the domestic (Soviet) and international contexts. Nationalist leaders within the Soviet Union debate the appropriate tactics and pace to pursue their goals. The Soviet leadership dabates the extent to which autonomy may be granted to the nationalities. Western leaders consider their options in responding to the changes in the Soviet Union, changes which necessitate an overhaul of policies nearly a half-century old as well as some “new thinking” on their parts.

The discussion centered on two issues: (1) What in general has been the response of the West to nationalist movements in the USSR and how appropriate has that response been? (2) Is there any validity to claims of Baltic “exceptionalism”? The following introduction comments briefly on these issues and places them into perspective by drawing on the discussion and exploring several key points.
Textural and Bile Acid‐Binding Properties of Muffins Impacted by Oat β‐Glucan with Different Molecular Weights
Authors: Sayar Sedat , Jannink Jean‐Luc , White Pamela J.
Published: September 2011

Water‐soluble β‐glucan (BG) extracted from a high‐BG oat line was treated with different amounts of lichenase (1→3)(1→4)‐β‐d‐glucanase) enzyme to yield three different molecular weight (MW) BG extracts. Low (LMW‐BG, 157,000), medium (MMW‐BG, 277,000), and high (HMW‐BG, 560,000) MW BG extracts were added to plain muffin formulations at a level of 0.52% (0.42% in the batter, 0.52% in the resultant muffins) to investigate the effect of MW of BG on textural and bile acid (BA) binding properties of the muffins. In addition, treatments were prepared containing LMW‐BG, MMW‐BG, and HMW‐BG extracts in amounts providing equivalent batter firmness as determined on a texture analyzer. Resultant BG concentrations (and per serving amounts) of these muffins were 1.36% (0.81 g/60 g muffin), 1.05% (0.63 g/60 g muffin), and 0.52% (0.31 g/60 g muffin), respectively; thus, the LMW treatment complied with a U.S. Food and Drug Administration health claim requiring 0.75 g of BG per serving. The firmness, springiness, and BA‐binding capacity of the muffins were unaffected by the MW of BG. However, when added at the maximum limit for equivalent batter firmness, the LMW treatment was more firm and less springy than the HMW treatment. Furthermore, BA‐binding capacities of LMW and MMW fractions tended to be greater than that of the HMW fraction when added at the maximum limit. These results add further evidence to the importance of fine‐tuning BG structure to provide maximum health benefits while maintaining high product quality.
Protein Extraction from Triticale Distillers Grains
Authors: Bandara Nandika , Chen Lingyun , Wu Jianping
Published: September 2011

Triticale is being actively explored as a feedstock for bioethanol production in Western Canada. Triticale distillers grains, an important coproduct of the bioethanol industry, are used mainly as animal feed. This study aims to develop methods of protein extraction from triticale distillers wet grains and distillers dried grains with solubles. Osborne fractionation showed low protein extractability because excessive protein denaturation occurred during sample preparation. Five methods were used to extract proteins: pH shifting, 60% ethanol, alkaline‐ethanol solution, glacial acetic acid, and enzyme‐aided extraction. Extracts obtained with the alkaline‐ethanol and glacial acetic acid methods showed comparatively higher protein contents (≈61–65%) when compared with the other extraction methods (≈35–57%). Enzyme‐aided extraction with Protex 6L yielded 75–82% protein at a content of 43–57%, depending on the types of raw materials. Establishing methods of protein extraction from triticale distillers grains would facilitate further studies on new uses of triticale proteins.
Solvent Retention Capacity (SRC) Testing of Wheat Flour: Principles and Value in Predicting Flour Functionality in Different Wheat‐Based Food Processes and in Wheat Breeding—A Review
Authors: Kweon Meera , Slade Louise , Levine Harry
Published: September 2011

Solvent retention capacity (SRC) technology, its history, principles, and applications are reviewed. Originally, SRC testing was created and developed for evaluating soft wheat flour functionality, but it has also been shown to be applicable to evaluating flour functionality for hard wheat products. SRC is a solvation test for flours that is based on the exaggerated swelling behavior of component polymer networks in selected individual diagnostic solvents. SRC provides a measure of solvent compatibility for the three functional polymeric components of flour—gluten, damaged starch, and pentosans—which in turn enables prediction of the functional contribution of each of these flour components to overall flour functionality and resulting finished‐product quality. The pattern of flour SRC values for the four diagnostic SRC solvents (water, dilute aqueous lactic acid, dilute aqueous sodium carbonate, and concentrated aqueous sucrose solutions), rather than any single individual SRC value, has been shown to be critical to various successful end‐use applications. Moreover, a new predictive SRC parameter, the gluten performance index (GPI), defined as GPI = lactic acid/(sodium carbonate + sucrose) SRC values, has been found to be an even better predictor of the overall performance of flour glutenin in the environment of other modulating networks of flour polymers. SRC technology is a unique diagnostic tool for predicting flour functionality, and its applications in soft wheat breeding, milling, and baking are increasing markedly as a consequence of many successful, recently published demonstrations of its extraordinary power and scope.
Root-Knot Disease Caused by Meloidogyne arenaria and M. javanica in Teak in São Paulo State, Brazil
Authors: de Araújo Filho J. V. , Machado A. C. Z. , de Faria R. S. C. A. , Camargo L. E. A.
Published: September 2011

Teak (Tectona grandis Linn. F.) is one of the most important forest crops in Brazil, occupying areas in different regions, such as Goiás, Mato Grosso, Paraná, and São Paulo states. Teak wood is used for many purposes such as shipbuilding, rolling and plywood, firewood, and charcoal. In May 2011, teak symptomatic feeder root samples, exhibiting inconspicuous, small galls, were collected in the municipality of Piracicaba, São Paulo State, Brazil (22°41′46.90″S, 47°38′36.84″W). Specimens were identified through perineal patterns and esterase phenotypes of 20 adult females (1,2). Perineal patterns and esterase phenotypes were consistent with those described for Meloidogyne arenaria (Neal, 1889) Chitwood, 1949 and M. javanica (Treub, 1885) Chitwood, 1949. Perineal patterns of M. arenaria showed a low dorsal arch, compressed dorsolaterally, with lateral field marked by some forked and broken striae; no punctate markings between anus and tail terminus were observed. Perineal patterns of M. javanica were rounded, with low dorsal arch, striae smooth, lateral field distinct, clearly demarcated from striae by parallel lines. From the esterase electrophoresis we obtained A2 (Rm:1.2;1.3) and J3 (Rm:1.0;1.25;1.4) phenotypes, typical from M. arenaria and M. javanica, respectively. To our knowledge, this is the first report of M. arenaria parasitizing teak roots in Brazil and elsewhere (new host) and the first report of M. javanica infecting teak in the State of São Paulo. Previously, M. javanica was reported to be infecting teak-growing areas in the State of Mato Grosso (3). This finding has a great importance, not only by the inclusion of these parasites in teak pathological scenario, but also for predicting possible damage in plant species used in teak-based intercropping systems.

References: (1) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 22:10, 1990. (2) K. M. Hartman and J. N. Sasser. 1985. Page 115 in: An Advanced Treatise on Meloidogyne. Volume II, Methodology. K. R. Barker et al., eds. North Carolina State University Graphics, Raleigh,1985. (3) R. A. Silva et al. Nematol. Bras. 27:261, 2003.
The transfer of motor functional strategies via action observation
Authors: Sartori Luisa , Xompero Francesca , Bucchioni Giulia , Castiello Umberto
Published: September 2011

When someone is choosing one piece from a bowl full of fruit, many pieces are within reach and visible. Although the desired piece seems to govern the particular pattern and direction of that person's reaching movement, the selection process is not impervious to the presence of task-irrelevant information (i.e. the other fruits). Evidence suggests that the kinematics of reach-to-grasp actions for a desired object integrates the motor features of all the objects which might become potential targets. Transcranial magnetic stimulation (TMS) and motor-evoked potentials (MEPs) were used by us to establish if that motor integration process can be transferred to an onlooker. Our results indicate that observation of hybrid reach-to-grasp movement kinematics is reflected in the observer's pattern of MEP amplitudes. This effect can be defined as a form of motor resonance which operates by ‘reading’ the kinematics of an observed action. The brain's ability to mirror motor integration processes while observing someone else's action helps an onlooker to understand what the other person is doing and to predict his/her motor alternatives.
Harmonine, a defence compound from the harlequin ladybird, inhibits mycobacterial growth and demonstrates multi-stage antimalarial activity
Authors: Röhrich Christian Rene , Ngwa Che Julius , Wiesner Jochen , Schmidtberg Henrike , Degenkolb Thomas , Kollewe Christian , Fischer Rainer , Pradel Gabriele , Vilcinskas Andreas
Published: September 2011

The harlequin ladybird beetle
Harmonia axyridis
has been introduced in many countries as a biological control agent, but has become an invasive species threatening the biodiversity of native ladybirds. Its invasive success has been attributed to its vigorous resistance against diverse pathogens. This study demonstrates that harmonine ((17
R
,9
Z
)-1,17-diaminooctadec-9-ene), which is present in
H. axyridis
haemolymph, displays broad-spectrum antimicrobial activity that includes human pathogens. Antibacterial activity is most pronounced against fast-growing mycobacteria and
Mycobacterium tuberculosis
, and the growth of both chloroquine-sensitive and -resistant
Plasmodium falciparum
strains is inhibited. Harmonine displays gametocytocidal activity, and inhibits the exflagellation of microgametocytes and zygote formation. In an
Anopheles stephensi
mosquito feeding model, harmonine displays transmission-blocking activity.
Overall dynamic properties of three-dimensional periodic elastic composites
Authors: Srivastava Ankit , Nemat-Nasser Sia
Published: September 2011

This article presents a method for the homogenization of three-dimensional periodic elastic composites. It allows for the evaluation of the averaged overall frequency-dependent dynamic material constitutive tensors relating the averaged dynamic field variable tensors of velocity, strain, stress and linear momentum. Although the form of the dynamic constitutive relation for three-dimensional elastodynamic wave propagation has been known, this is the first time that explicit calculations of the effective parameters (for three dimensions) are presented. We show that for three-dimensional periodic composites, the overall compliance (stiffness) tensor, as produced directly by our formulation, is Hermitian, regardless of whether the corresponding unit cell is geometrically or materially symmetric. Overall, mass density is shown to be a tensor and, like the overall compliance tensor, always Hermitian. The average strain and linear momentum tensors are, however, coupled, and the coupling tensors are shown to be each others' Hermitian transpose. Finally, we present a numerical example of a three-dimensional periodic composite composed of elastic cubes periodically distributed in an elastic matrix. The presented results corroborate the predictions of the theoretical treatment illustrating the frequency dependence of the constitutive parameters. We also show that the effective properties calculated in this paper satisfy the dispersion relation of the composite.
Fine-scale thermal adaptation in a green turtle nesting population
Authors: Weber Sam B. , Broderick Annette C. , Groothuis Ton G. G. , Ellick Jacqui , Godley Brendan J. , Blount Jonathan D.
Published: September 2011

The effect of climate warming on the reproductive success of ectothermic animals is currently a subject of major conservation concern. However, for many threatened species, we still know surprisingly little about the extent of naturally occurring adaptive variation in heat-tolerance. Here, we show that the thermal tolerances of green turtle (
Chelonia mydas
) embryos in a single, island-breeding population have diverged in response to the contrasting incubation temperatures of nesting beaches just a few kilometres apart. In natural nests and in a common-garden rearing experiment, the offspring of females nesting on a naturally hot (black sand) beach survived better and grew larger at hot incubation temperatures compared with the offspring of females nesting on a cooler (pale sand) beach nearby. These differences were owing to shallower thermal reaction norms in the hot beach population, rather than shifts in thermal optima, and could not be explained by egg-mediated maternal effects. Our results suggest that marine turtle nesting behaviour can drive adaptive differentiation at remarkably fine spatial scales, and have important implications for how we define conservation units for protection. In particular, previous studies may have underestimated the extent of adaptive structuring in marine turtle populations that may significantly affect their capacity to respond to environmental change.
Evolving ecological networks and the emergence of biodiversity patterns across temperature gradients
Authors: Stegen James C. , Ferriere Regis , Enquist Brian J.
Published: September 2011

In ectothermic organisms, it is hypothesized that metabolic rates mediate influences of temperature on the ecological and evolutionary processes governing biodiversity. However, it is unclear how and to what extent the influence of temperature on metabolism scales up to shape large-scale diversity patterns. In order to clarify the roles of temperature and metabolism, new theory is needed. Here, we establish such theory and model eco-evolutionary dynamics of trophic networks along a broad temperature gradient. In the model temperature can influence, via metabolism, resource supply, consumers' vital rates and mutation rate. Mutation causes heritable variation in consumer body size, which diversifies and governs consumer function in the ecological network. The model predicts diversity to increase with temperature if resource supply is temperature-dependent, whereas temperature-dependent consumer vital rates cause diversity to decrease with increasing temperature. When combining both thermal dependencies, a unimodal temperature–diversity pattern evolves, which is reinforced by temperature-dependent mutation rate. Studying coexistence criteria for two consumers showed that these outcomes are owing to temperature effects on mutual invasibility and facilitation. Our theory shows how and why metabolism can influence diversity, generates predictions useful for understanding biodiversity gradients and represents an extendable framework that could include factors such as colonization history and niche conservatism.
Evolution of learned strategy choice in a frequency-dependent game
Authors: Katsnelson Edith , Motro Uzi , Feldman Marcus W. , Lotem Arnon
Published: September 2011

In frequency-dependent games, strategy choice may be innate or learned. While experimental evidence in the producer–scrounger game suggests that learned strategy choice may be common, a recent theoretical analysis demonstrated that learning by only some individuals prevents learning from evolving in others. Here, however, we model learning explicitly, and demonstrate that learning can easily evolve in the whole population. We used an agent-based evolutionary simulation of the producer–scrounger game to test the success of two general learning rules for strategy choice. We found that learning was eventually acquired by all individuals under a sufficient degree of environmental fluctuation, and when players were phenotypically asymmetric. In the absence of sufficient environmental change or phenotypic asymmetries, the correct target for learning seems to be confounded by game dynamics, and innate strategy choice is likely to be fixed in the population. The results demonstrate that under biologically plausible conditions, learning can easily evolve in the whole population and that phenotypic asymmetry is important for the evolution of learned strategy choice, especially in a stable or mildly changing environment.
ASPM regulates Wnt signaling pathway activity in the developing brain
Authors: Buchman Joshua J. , Durak Omer , Tsai Li-Huei
Published: September 2011

Autosomal recessive primary microcephaly (MCPH) is a neural developmental disorder in which patients display significantly reduced brain size. Mutations in Abnormal Spindle Microcephaly (ASPM) are the most common cause of MCPH. Here, we investigate the underlying functions of Aspm in brain development and find that Aspm expression is critical for proper neurogenesis and neuronal migration. The Wnt signaling pathway is known for its roles in embryogenesis, and genome-wide siRNA screens indicate that ASPM is a positive regulator of Wnt signaling. We demonstrate that knockdown of Aspm results in decreased Wnt-mediated transcription, and that expression of stabilized β-catenin can rescue this deficit. Finally, coexpression of stabilized β-catenin can rescue defects observed upon in vivo knockdown of Aspm. Our findings provide an impetus to further explore Aspm's role in facilitating Wnt-mediated neurogenesis programs, which may contribute to psychiatric illness etiology when perturbed.
A protein synthesis and nitric oxide-dependent presynaptic enhancement in persistent forms of long-term potentiation
Authors: Johnstone Victoria P.A. , Raymond Clarke R.
Published: September 2011

Long-term potentiation (LTP) is an important process underlying learning and memory in the brain. At CA3–CA1 synapses in the hippocampus, three discrete forms of LTP (LTP1, 2, and 3) can be differentiated on the basis of maintenance and induction mechanisms. However, the relative roles of pre- and post-synaptic expression mechanisms in LTP1, 2, and 3 are unknown. Neurotransmitter release in the expression of LTP1, 2, and 3 was measured via FM 1–43 destaining from CA3 terminals in hippocampal slices from male Wistar rats (7–8 wk). No difference in vesicle turnover rate was observed for LTP1 up to 160 min following induction by one train of theta-burst stimulation (1TBS). A presynaptic enhancement was found for LTP2 at 160 min after induction by 4TBS, and for LTP3 at both 80 and 160 min after induction by 8TBS. Inhibition of nitric oxide (NO) signaling blocked both LTP2 and LTP3 maintenance and the associated enhanced release. LTP2 maintenance and its presynaptic expression were dependent on protein synthesis, but not gene transcription. LTP3 maintenance was dependent on both translation and transcription, but like LTP2, the enhanced release only required translation. These data considerably strengthen the mechanistic separation of LTP1, 2, and 3, supporting a model of multiple, discrete forms of LTP at CA3–CA1 synapses rather than different temporal phases.
A Plasmodesmata-Localized Protein Mediates Crosstalk between Cell-to-Cell Communication and Innate Immunity inArabidopsis
Authors: Lee Jung-Youn , Wang Xu , Cui Weier , Sager Ross , Modla Shannon , Czymmek Kirk , Zybaliov Boris , van Wijk Klaas , Zhang Chong , Lu Hua , Lakshmanan Venkatachalam
Published: September 2011

Plasmodesmata (PD) are thought to play a fundamental role in almost every aspect of plant life, including normal growth, physiology, and developmental responses. However, how specific signaling pathways integrate PD-mediated cell-to-cell communication is not well understood. Here, we present experimental evidence showing that the Arabidopsis thaliana plasmodesmata-located protein 5 (PDLP5; also known as HOPW1-1-INDUCED GENE1) mediates crosstalk between PD regulation and salicylic acid–dependent defense responses. PDLP5 was found to localize at the central region of PD channels and associate with PD pit fields, acting as an inhibitor to PD trafficking, potentially through its capacity to modulate PD callose deposition. As a regulator of PD, PDLP5 was also essential for conferring enhanced innate immunity against bacterial pathogens in a salicylic acid–dependent manner. Based on these findings, a model is proposed illustrating that the regulation of PD closure mediated by PDLP5 constitutes a crucial part of coordinated control of cell-to-cell communication and defense signaling.
Design and construction of multicrystal analyser detectors using Rowland circles: application to MAD26 at ALBA
Authors: Peral Inma , McKinlay Jonathan , Knapp Michael , Ferrer Salvador
Published: September 2011

A concept is given for describing multicrystal analyser detectors (MADs), as they are in use for synchrotron powder diffraction, on the basis of the Rowland circle construction. The Rowland circle is typically used to describe focusing geometries and can be adapted for the case of MADs working at a single energy as well as in a limited energy range. With this construction it is also possible to quantify and optimize the walk of the beam along non-central crystals which is inevitable in certain detector designs. The results of this geometrical inspection are correlated with a real detector design that is implemented at the ALBA synchrotron facility in Spain. An error budget is given to estimate the influence and amount of tolerance of the manufacturing process.
Susceptibility of piglets to enterotoxigenic Escherichia coli is not related to the expression of MUC13 and MUC20
Authors: Schroyen M. , Stinckens A. , Verhelst R. , Geens M. , Cox E. , Niewold T. , Buys N.
Published: September 2011

Enterotoxigenic Escherichia coli (ETEC) is one of the most frequently isolated enteropathogens in production animals, especially pigs and calves. Economically, the swine industry is by far the most affected by infections with ETEC because of mortality, morbidity and decreased growth rate of newborn and early‐weaned piglets. After ingestion by the animal, these bacteria attach themselves to specific receptors on the small intestinal epithelium by means of proteinaceous surface appendages, the fimbriae. The F4 fimbriae, which attach to the F4 receptor, are the most studied. The aim of our study was to investigate gene expression in the small intestine of piglets of MUC13 and MUC20 in relation to animals with a different treatment towards or a different reaction on ETEC‐F4ac by means of quantitative reverse transcription chain reaction (qRT/PCR). MUC13 and MUC20 are positional candidate genes for this F4ac receptor and are located in the region on SSC13q41 that segregates with the susceptibility to ETEC‐F4ac. The condition of the small intestine is crucial when examining expression differences between different samples. Therefore, the expression of two genes, fatty‐acid binding protein 2, intestinal (FABP2) and pancreatitis‐associated protein (PAP), now known as regenerating islet‐derived 3 alpha (REG3A) in the small intestine was simultaneously checked. FABP2, a standard for epithelial content, reflects the state of damage, whereas REG3A is a measure for inflammation in the small intestine. The four different substudies presented here suggest that expression of MUC13 and MUC20 is not related to the susceptibility of piglets to ETEC‐F4ac.
IL‐13‐inducedMUC5ACproduction and goblet cell differentiation is steroid resistant in human airway cells
Authors: Kanoh S. , Tanabe T. , Rubin B. K.
Published: September 2011

Background

Glucocorticosteroids (GCS) are used to treat bronchial asthma, but are not uniformly effective, especially in severe asthma.IL‐13 is a T helper type 2 cytokine implicated in the pathogenesis of asthma, and IL‐13 induces mucus production and goblet cell hyperplasia in airway epithelial cells. The effect ofGCSonIL‐13‐induced mucin production is not well characterized.

Objective

The aim of this study was to evaluate the effect of dexamethasone (Dex), a potent syntheticGCS, onIL‐13‐inducedMUC5ACmucin expression and goblet cell proliferation in differentiated normal human bronchial epithelial cells (NHBECs).

Methods

NHBECs were cultured for 14 days at an air–liquid interface with IL‐13, with or withoutDex.MUC5ACprotein secretion andmRNAexpression was determined usingELISAand quantitative real‐timePCR.IL‐8 production was assayed usingELISA. Histochemical analysis was performed usingH&Eand periodic acid‐Schiff stain, andMUC5ACimmunostaining.

Results

AlthoughDex dose dependently inhibitedIL‐8 release induced by 5 ng/mLIL‐13,Dex 0.001–1 μg/mL had no effect onIL‐13 inducedMUC5ACprotein secretion ormRNAexpression.Dex paradoxically increasedMUC5ACinduced byIL‐13 at 0.5 and 1 ng/mL, but had no effect alone or withIL‐13 at 0.1 ng/mL.Dex 0.001–1 μg/mL did not inhibit the differentiation of cells into goblet cells andMUC5AC‐positive cells induced byIL‐13.

Conclusion and Clinical Relevance

Dex at therapeutic concentrations did not inhibit the effects ofIL‐13 on goblet cell differentiation, characteristic of severe asthma. Paradoxically,MUC5ACproduction was increased with lower doseIL‐13 exposure. This may lead to airway mucus obstruction commonly seen in life‐threatening asthma.
Conjunctival provocation with airborne allergen in patients with atopic keratoconjunctivitis
Authors: Nivenius E. , Van der Ploeg I. , Gafvelin Guro , Van Hage M. , Montan P. G.
Published: September 2011

Background

Atopic keratoconjunctivitis (AKC) is a chronic eye disease with periods of exacerbations. Many patients experience no obvious seasonal variation, although a majority of patients are allergic to common airborne allergens.

Objective

To investigate the allergic reaction, to conjunctival provocation with airborne allergens, in patients with AKC.

Methods

Eleven patients with AKC and birch and/or grass pollen allergy participated in the study, which was performed outside the pollen season. Five patients with seasonal allergic conjunctivitis (SAC) and five healthy subjects were included for validation purposes. The challenge was performed in one eye with the allergen, to which the patient was reactive, and with dilution buffer in the other eye. Signs and symptoms from both eyes were graded at baseline and at 10 min, 8 and 48 h after provocation. Tear fluid was collected from both eyes for cytokine analyses at baseline and at 8 and 48 h.

Results

A significant change in clinical symptoms and signs, (redness and chemosis) was evident 10 min after provocation compared with baseline (P = 0.005) and compared with the unprovoked eye (P = 0.005) in AKC subjects. These parameters were normalized after 8 and 48 h. A significant increase for IFN‐γ (P = 0.021) and IL‐6 (P = 0.015), and a near significant increase for IL‐10 (P = 0.066) were seen in the tear fluid of the challenged eye at 48 h after provocation vs. baseline and vs. the control eye for IFN‐γ (P = 0.005), IL‐6 (P = 0.028) and IL‐10 (P = 0.008) in AKC subjects.

Conclusion and Clinical Relevance

In this single dose allergen provocation study, AKC patients responded with a typical IgE‐mediated allergic reaction. An increase in cytokines at 48 h after the challenge was demonstrated and might, with further studies, give us a better understanding of the nature of inflammation in AKC.
Staphylococcal‐derived superantigen enhances peanut induced Th2 responses in the skin
Authors: Forbes‐Blom E. , Camberis M. , Prout M. , Tang S.‐C. , Le Gros G.
Published: September 2011

Background

The allergen‐induced activation and expansion of IL‐4 producing T helper type 2 (Th2) cells is a key event in the initiation and progression of allergic disease. Intriguingly, concomitant early childhood staphylococcal skin infections are being increasingly implicated in the allergen‐induced switch of primary T cell responses towards the Th2 phenotype.

Objective

We sought to identify whether or not staphylococcal‐derived superantigen can influence the primary T cell response in the skin to food allergens with a view to determining whether such exposures create the immune pathology that predisposes to the development of food allergy.

Methods

Using a novel Th2 reporter model, we determined the ability of the staphylococcal superantigen (SEB) to influence priming in the skin of IL‐4 expressing Th2 cells by peanut extract (PE). Factors including the effect of SEB on the magnitude of the Th2 response in the skin draining lymph nodes, T cell receptor V region usage and the influence of endotoxin were evaluated.

Results

Primary exposure to PE and SEB lead to significantly enhanced PE specific Th2 responses when the mice were subsequently exposed to PE alone. The enhancement of the Th2 response was dependent on the Vβ‐binding properties of the SEB, but was not affected by endotoxin‐mediated TLR‐4 effects or strain differences in the mice.

Conclusions and Clinical Relevance

These results identify that in the skin environment, the presence of SEB can significantly increase the numbers of allergen‐induced Th2 cells which develop in response to subsequent allergen exposure. These data highlight the process by which individuals may become pathologically sensitized to food allergens in early life.