bluuebunny/crossref_metadata_2025 huggingface dataset:
Antitrust Corporate Governance and Compliance
Authors: Sokol D. Daniel , Abrantes-Metz Rosa
Published: June 2015

Both theoretical and empirical work in a number of different fields, including economics, accounting, finance, organizational theory, and sociology provides important insights indicating that a firm is not merely a single entity in its actions. Rather, a firm is made up of a number of various components, each of which has its own incentives that shape firm behavior. This chapter reviews both the antitrust and the non-antitrust literatures on compliance and corporate governance to provide a clearer picture of the extant literature and the theoretical and empirical gaps within the antitrust literature to better inform antitrust policy on detecting cartels. This chapter explores the scholarship both within and outside of antitrust to better understand internal detection of wrongdoing and improved compliance in the antitrust cartel context.
The Roles of Banks in Financial Systems
Authors: Allen Franklin , Carletti Elena , Gu Xian
Published: June 2015

Banks perform various roles in the economy. First, they ameliorate the information problems between investors and borrowers by monitoring the latter and ensuring a proper use of the depositors’ funds. Second, they provide intertemporal smoothing of risk that cannot be diversified at a given point in time, as well as insurance to depositors against unexpected consumption shocks. Because of the maturity mismatch between their assets and liabilities, however, banks are subject to the possibility of runs and systemic risk. Third, banks contribute to the growth of the economy. Fourth, they perform an important role in corporate governance. The relative importance of the different roles of banks varies substantially across countries and times but, banks are always critical to the financial system.
Commercial Banking and Shadow Banking
Authors: Boot Arnoud W. A. , Thakor Anjan V.
Published: June 2015

In this chapter we examine the implications of the increasing integration of banks and financial markets for the evolution of each as well as the design of prudential regulation. The growth of the use of depository-banking-originated mortgage-backed securities sold in the market and used as collateral to back short-term funding transactions in the shadow banking sector illustrates this intertwining of banks and markets, and the potential systemic risk dangers of this, as is apparent from the recent crisis. An important implication of this integration is that it is becoming increasingly difficult to isolate banking risks from financial market risks. Building on contemporary theories of financial intermediation, relationship banking, and securitization, we show how these theories inform us about the underlying causes of the seismic shifts that have occurred in financial markets in recent years, and what they suggest about the kinds of regulatory reforms that may be most fruitful. We end with a list of open research questions suggested by our analysis.
Risk Management in Banking
Authors: Allen Linda , Saunders Anthony
Published: June 2015

In this chapter we describe the risk management challenges faced by financial institutions. The very nature of the banking business requires that financial firms become experts at risk assessment in order to manage their own inventories of risk, obtained during day-to-day business transactions with bank customers. Banks are exposed to interest rate risk, currency risk, liquidity risk, credit risk, and operational risk. The first step in a risk management program is accurate risk measurement. A useful risk measurement tool is the Value at Risk (VaR) model. The 99% VaR model produces predictions such as the worse loss that may occur in every 100 days (or years). In contrast, the 99% expected shortfall denotes the average of all losses that occur with a 1 percent probability. We show that the roots of the global financial crisis of 2007–08 can be found in the failure of financial intermediaries to measure and manage risk properly.
Sovereign Debt Crises
Authors: Correa Ricardo , Sapriza Horacia
Published: June 2015

Sovereign debt crises have occurred frequently over the past two centuries. In recent years, the timing of sovereign crises has coincided with or directly followed banking crises. The link between sovereigns and banks tightened as financial “safety nets,” which increased the contingent liability that the banking sector represents for the sovereign, became more common. This chapter analyzes the transmission channels between sovereigns and banks, with a focus on the effect of sovereign distress on bank solvency and financing. It then highlights the notable cost to the real economy of the close connection between sovereigns and banks. Breaking the “feedback loop” between these two sectors should be an important policy priority.
Cytoplasmic and Nuclear Localizations Are Important for the Hypersensitive Response Conferred by Maize Autoactive Rp1-D21 Protein
Authors: Wang Guan-Feng , Balint-Kurti Peter J.
Published: June 2015

Disease resistance (R) genes have been isolated from many plant species. Most encode nucleotide binding leucine-rich repeat (NLR) proteins that trigger a rapid localized programmed cell death called the hypersensitive response (HR) upon pathogen recognition. Despite their structural similarities, different NLR are distributed in a range of subcellular locations, and analogous domains play diverse functional roles. The autoactive maize NLR gene Rp1-D21 derives from an intragenic recombination between two NLR genes, Rp1-D and Rp1-dp2, and confers a HR independent of the presence of a pathogen. Rp1-D21 and its N-terminal coiled coil (CC) domain (CCD21) confer autoactive HR when transiently expressed in Nicotiana benthamiana. Rp1-D21 was predominantly localized in cytoplasm with a small amount in the nucleus, while CCD21 was localized in both nucleus and cytoplasm. Targeting of Rp1-D21 or CCD21 predominantly to either the nucleus or the cytoplasm abolished HR-inducing activity. Coexpression of Rp1-D21 or CCD21 constructs confined, respectively, to the nucleus and cytoplasm did not rescue full activity, suggesting nucleocytoplasmic movement was important for HR induction. This work emphasizes the diverse structural and subcellular localization requirements for activity found among plant NLR R genes.
Susceptibility of Greenhouse Ornamentals to Phytophthora capsici and P. tropicalis
Authors: Enzenbacher T. B. , Naegele R. P. , Hausbeck M. K.
Published: June 2015

The susceptibility of fabaceous (Lupinus and Lathyrus spp.) and solanaceous (Calibrachoa, Browallia, Nicotiana, Nierembergia, and Petunia spp.) ornamental plants compared with straightneck squash (Cucurbita pepo) inoculated with Phytophthora capsici and P. tropicalis was investigated in greenhouse studies. Four P. capsici isolates and one P. tropicalis isolate were evaluated. Flowering tobacco (Nicotiana × sanderae), sweet pea (Lathyrus latifolius), lupine (Lupinus polyphyllus), squash, and million bells (Calibrachoa × hybrida) were susceptible to P. capsici and P. tropicalis. Bush violet (Browallia speciosa) and cup flower (Nierembergia scoparia) were not susceptible to either pathogen. Petunia (Petunia × hybrida) was susceptible to P. capsici but not P. tropicalis. Area under the plant growth curve (AUPGC) was also affected in some susceptible plants. AUPGC was significantly different in inoculated plants compared with the untreated controls of Nicotiana and Calibrachoa. In addition, six Calibrachoa cultivars were evaluated for susceptibility to P. capsici and P. tropicalis in a separate experiment. Although all Calibrachoa cultivars were susceptible to P. capsici and P. tropicalis, ‘Celebration Purple Star’ displayed limited disease following inoculation with either pathogen. Calibrachoa ‘Cabaret’ and ‘Can-Can’ inoculated with P. capsici or P. tropicalis displayed significant differences in AUPGC compared with the uninoculated controls. ‘Callie’, ‘Million Bells Cherry Pink’, and ‘Superbells’ had significantly reduced AUPGC compared with the controls when inoculated with P. tropicalis but not P. capsici. These results expand the host range of P. capsici to include Calibrachoa spp., L. polyphyllus, and Lathyrus latifolius, and P. tropicalis to include L. latifolius, Nicotiana spp., and straightneck squash.
Real-Time PCR for Detection and Identification of Anguina funesta, A. agrostis, A. tritici, and A. pacificae
Authors: Li Wenbin , Yan Zonghe , Nakhla Mark K. , Skantar Andrea M.
Published: June 2015

A number of seed, leaf, and stem gall nematodes are of significance to the forage and landscape grass and livestock industries. In North America, the bentgrass nematode, Anguina agrostis, reduces seed production on Agrostis tenuis and several other grass species. Anguina funesta is a seed-gall nematode that is most significant for its association with the toxigenic bacteria Rathayibacter toxicus. The wheat seed gall nematode A. tritici causes significant damage to wheat and other cereals; although it has been found in many countries worldwide, it has not been detected in the United States since 1975. Molecular methods based upon sequence variation in the ribosomal internal spacer region are useful for accurate identification of Anguina spp. Described herein are new species-specific primers and TaqMan probes for real-time polymerase chain reaction (PCR) identification of A. agrostis, A. funesta, A. tritici, and A. pacificae. Primer and probe combinations were each specific for the intended species and were sensitive enough to detect as few as 1.25 copies of nematode ribosomal DNA. PCR was also specific and sensitive in duplex assays that included genus-specific internal control primers as well as species-specific primers and probes. These standardized real-time PCR protocols should facilitate fast and accurate identification of Anguina spp. by diagnostic laboratories.
The Effect of Delayed-Dormant Chemical Treatments on Demethylation Inhibitor (DMI) Sensitivity in a DMI-resistant Population of Venturia inaequalis
Authors: Frederick Zachary A. , Villani Sara M. , Cox Kerik D.
Published: June 2015

Demethylation inhibitor (DMI) fungicides are an effective means to manage apple scab caused by Venturia inaequalis. Unfortunately, practical resistance to DMI fungicide chemistries is prevalent in populations in New York and the New England states. Management practices that delay the development of DMI resistance in V. inaequalis populations are highly desired by regional apple producers. Trials were conducted in a New York apple orchard during the 2011 and 2012 growing seasons to determine the impact of delayed-dormant (after bud break, but prior to green tissue) chemical treatments on the DMI sensitivity of a V. inaequalis population with stable resistance to DMI fungicides. Delayed-dormant treatment programs consisted of either an application of a copper fungicide, a manganese sanitation product, a DMI fungicide (myclobutanil), or no fungicide. Sensitivity to the DMI fungicide myclobutanil was evaluated for a minimum of 25 V. inaequalis single lesion conidial isolates from each of four replicated treatment blocks. In both years, mean percent relative growth on myclobutanil amended media for V. inaequalis isolates from the copper treatment program were significantly (P < 0.05) lower than isolates from blocks did not receive a delayed dormant fungicide treatment. The effect of the manganese treatment was inconsistent between years. V. inaequalis isolates collected from the myclobutanil treatment program were not significantly (P > 0.05) different in myclobutanil sensitivity from isolates collected from the blocks that did not receive a delayed dormant fungicide treatment. Overall, the results suggest that delayed dormant treatments of copper may favorably impact the myclobutanil sensitivity for a population of V. inaequalis with resistance to DMI fungicides, and should be considered as a standard management practice in apple production.
Vitis rupestrisB38 Confers Isolate-Specific Quantitative Resistance to Penetration byErysiphe necator
Authors: Barba Paola , Cadle-Davidson Lance , Galarneau Erin , Reisch Bruce
Published: June 2015

Vitis rupestris B38 is a North American grapevine resistant to the major pathogen of cultivated grapevines, Erysiphe necator. Sources of powdery mildew resistance, like V. rotundifolia, are widely used in grape breeding but are already threatened, even before commercialization, by isolates that can reproduce on Run1 and other rotundifolia-derived breeding lines. Thus, complementary sources of resistance are needed to improve resistance durability. The segregation of foliar powdery mildew severity in an F1family, derived from a cross of V. rupestris B38 × V. vinifera ‘Chardonnay’, was observed in the field over three growing seasons and in potted vines following single-isolate inoculation. A pattern of continuous variation was observed in every instance. Mechanisms of resistance were analyzed on the resistant and susceptible parent by using microscopy to quantify the ability of the pathogen to penetrate and to form a colony on detached leaves. While ‘Chardonnay’ was susceptible in all tested conditions, V. rupestris B38 resistance was characterized by a reduction in pathogen penetration, with an effect of leaf position and significant differences among powdery mildew isolates. Segregation of the ability of the pathogen to penetrate and form a colony in F1individuals showed a pattern of quantitative penetration resistance with no delay or restriction on colony formation once penetration has been achieved. Moreover, V. rupestris B38 showed an enhanced penetration resistance to a powdery mildew isolate with the ability to overcome the Run1 gene, making it an interesting resistance source to prolong the durability of this gene.
Varroa destructor
changes its cuticular hydrocarbons to mimic new hosts
Authors: Le Conte Y. , Huang Z. Y. , Roux M. , Zeng Z. J. , Christidès J.-P. , Bagnères A.-G.
Published: June 2015

Varroa destructor
(
Vd
) is a honeybee ectoparasite. Its original host is the Asian honeybee,
Apis cerana
, but it has also become a severe, global threat to the European honeybee,
Apis mellifera
. Previous studies have shown that
Varroa
can mimic a host's cuticular hydrocarbons (HC), enabling the parasite to escape the hygienic behaviour of the host honeybees. By transferring mites between the two honeybee species, we further demonstrate that
Vd
is able to mimic the cuticular HC of a novel host species when artificially transferred to this new host. Mites originally from
A. cerana
are more efficient than mites from
A. mellifera
in mimicking HC of both
A. cerana
and
A. mellifera
. This remarkable adaptability may explain their relatively recent host-shift from
A. cerana
to
A. mellifera
.
Gerald Beresford Whitham. 13 December 1927 — 26 January 2014
Authors: Minzoni A. A. , Smyth N. F.
Published: June 2015

Gerald Beresford Whitham was one of the leading applied mathematicians of the twentieth century. His original, deep and insightful research into nonlinear wave propagation formed the foundation of and mathematical techniques for much of the current research in this area. Indeed, many of these ideas and techniques have spread beyond wave propagation research into other areas, such as reaction–diffusion, and has influenced research in pure mathematics. His textbook
Linear and nonlinear waves
, published in 1974, is still the standard reference for the mathematics of wave motion. Whitham was also instrumental in building from scratch the Department of Applied Mathematics at the California Institute of Technology and, through choosing key people in new, promising research areas, in making it into one of the leading centres of applied mathematics in the world, with an influence far beyond its small size. During his academic career, Whitham received major awards and prizes for his research. He was elected a Fellow of the Royal Society in 1965 and a Fellow of the American Academy of Arts and Sciences in 1959, and was awarded the Norbert Wiener Prize for Applied Mathematics in 1980.
Edge effects in game-theoretic dynamics of spatially structured tumours
Authors: Kaznatcheev Artem , Scott Jacob G. , Basanta David
Published: June 2015

Cancer dynamics are an evolutionary game between cellular phenotypes. A typical assumption in this modelling paradigm is that the probability of a given phenotypic strategy interacting with another depends exclusively on the abundance of those strategies without regard for local neighbourhood structure. We address this limitation by using the Ohtsuki–Nowak transform to introduce spatial structure to the go versus grow game. We show that spatial structure can promote the invasive (go) strategy. By considering the change in neighbourhood size at a static boundary—such as a blood vessel, organ capsule or basement membrane—we show an edge effect that allows a tumour without invasive phenotypes in the bulk to have a polyclonal boundary with invasive cells. We present an example of this promotion of invasive (epithelial–mesenchymal transition-positive) cells in a metastatic colony of prostate adenocarcinoma in bone marrow. Our results caution that pathologic analyses that do not distinguish between cells in the bulk and cells at a static edge of a tumour can underestimate the number of invasive cells. Although we concentrate on applications in mathematical oncology, we expect our approach to extend to other evolutionary game models where interaction neighbourhoods change at fixed system boundaries.
Unlimited multistability and Boolean logic in microbial signalling
Authors: Kothamachu Varun B. , Feliu Elisenda , Cardelli Luca , Soyer Orkun S.
Published: June 2015

The ability to map environmental signals onto distinct internal physiological states or programmes is critical for single-celled microbes. A crucial systems dynamics feature underpinning such ability is multistability. While unlimited multistability is known to arise from multi-site phosphorylation seen in the signalling networks of eukaryotic cells, a similarly universal mechanism has not been identified in microbial signalling systems. These systems are generally known as two-component systems comprising histidine kinase (HK) receptors and response regulator proteins engaging in phosphotransfer reactions. We develop a mathematical framework for analysing microbial systems with multi-domain HK receptors known as hybrid and unorthodox HKs. We show that these systems embed a simple core network that exhibits multistability, thereby unveiling a novel biochemical mechanism for multistability. We further prove that sharing of downstream components allows a system with
n
multi-domain hybrid HKs to attain 3
n
steady states. We find that such systems, when sensing distinct signals, can readily implement Boolean logic functions on these signals. Using two experimentally studied examples of two-component systems implementing hybrid HKs, we show that bistability and implementation of logic functions are possible under biologically feasible reaction rates. Furthermore, we show that all sequenced microbial genomes contain significant numbers of hybrid and unorthodox HKs, and some genomes have a larger fraction of these proteins compared with regular HKs. Microbial cells are thus theoretically unbounded in mapping distinct environmental signals onto distinct physiological states and perform complex computations on them. These findings facilitate the understanding of natural two-component systems and allow their engineering through synthetic biology.
A mathematical model of subpopulation kinetics for the deconvolution of leukaemia heterogeneity
Authors: Fuentes-Garí María , Misener Ruth , García-Munzer David , Velliou Eirini , Georgiadis Michael C. , Kostoglou Margaritis , Pistikopoulos Efstratios N. , Panoskaltsis Nicki , Mantalaris Athanasios
Published: June 2015

Acute myeloid leukaemia is characterized by marked inter- and intra-patient heterogeneity, the identification of which is critical for the design of personalized treatments. Heterogeneity of leukaemic cells is determined by mutations which ultimately affect the cell cycle. We have developed and validated a biologically relevant, mathematical model of the cell cycle based on unique cell-cycle signatures, defined by duration of cell-cycle phases and cyclin profiles as determined by flow cytometry, for three leukaemia cell lines. The model was discretized for the different phases in their respective progress variables (cyclins and DNA), resulting in a set of time-dependent ordinary differential equations. Cell-cycle phase distribution and cyclin concentration profiles were validated against population chase experiments. Heterogeneity was simulated in culture by combining the three cell lines in a blinded experimental set-up. Based on individual kinetics, the model was capable of identifying and quantifying cellular heterogeneity. When supplying the initial conditions only, the model predicted future cell population dynamics and estimated the previous heterogeneous composition of cells. Identification of heterogeneous leukaemia clones at diagnosis and post-treatment using such a mathematical platform has the potential to predict multiple future outcomes in response to induction and consolidation chemotherapy as well as relapse kinetics.
Investigating the causes and consequences of symbiont shuffling in a multi-partner reef coral symbiosis under environmental change
Authors: Cunning R. , Silverstein R. N. , Baker A. C.
Published: June 2015

Dynamic symbioses may critically mediate impacts of climate change on diverse organisms, with repercussions for ecosystem persistence in some cases. On coral reefs, increases in heat-tolerant symbionts after thermal bleaching can reduce coral susceptibility to future stress. However, the relevance of this adaptive response is equivocal owing to conflicting reports of symbiont stability and change. We help reconcile this conflict by showing that change in symbiont community composition (symbiont shuffling) in
Orbicella faveolata
depends on the disturbance severity and recovery environment. The proportion of heat-tolerant symbionts dramatically increased following severe experimental bleaching, especially in a warmer recovery environment, but tended to decrease if bleaching was less severe. These patterns can be explained by variation in symbiont performance in the changing microenvironments created by differentially bleached host tissues. Furthermore, higher proportions of heat-tolerant symbionts linearly increased bleaching resistance but reduced photochemical efficiency, suggesting that any change in community structure oppositely impacts performance and stress tolerance. Therefore, even minor symbiont shuffling can adaptively benefit corals, although fitness effects of resulting trade-offs are difficult to predict. This work helps elucidate causes and consequences of dynamism in symbiosis, which is critical to predicting responses of multi-partner symbioses such as
O. faveolata
to environmental change.
Negative effects of pesticides on wild bee communities can be buffered by landscape context
Authors: Park Mia G. , Blitzer E. J. , Gibbs Jason , Losey John E. , Danforth Bryan N.
Published: June 2015

Wild bee communities provide underappreciated but critical agricultural pollination services. Given predicted global shortages in pollination services, managing agroecosystems to support thriving wild bee communities is, therefore, central to ensuring sustainable food production. Benefits of natural (including semi-natural) habitat for wild bee abundance and diversity on farms are well documented. By contrast, few studies have examined toxicity of pesticides on wild bees, let alone effects of farm-level pesticide exposure on entire bee communities. Whether beneficial natural areas could mediate effects of harmful pesticides on wild bees is also unknown. Here, we assess the effect of conventional pesticide use on the wild bee community visiting apple (
Malus domestica
) within a gradient of percentage natural area in the landscape. Wild bee community abundance and species richness decreased linearly with increasing pesticide use in orchards one year after application; however, pesticide effects on wild bees were buffered by increasing proportion of natural habitat in the surrounding landscape. A significant contribution of fungicides to observed pesticide effects suggests deleterious properties of a class of pesticides that was, until recently, considered benign to bees. Our results demonstrate extended benefits of natural areas for wild pollinators and highlight the importance of considering the landscape context when weighing up the costs of pest management on crop pollination services.
Responses of tadpoles to hybrid predator odours: strong maternal signatures and the potential risk/response mismatch
Authors: Chivers Douglas P. , Mathiron Anthony , Sloychuk Janelle R. , Ferrari Maud C. O.
Published: June 2015

Previous studies have established that when a prey animal knows the identity of a particular predator, it can use this knowledge to make an ‘educated guess' about similar novel predators. Such generalization of predator recognition may be particularly beneficial when prey are exposed to introduced and invasive species of predators or hybrids. Here, we examined generalization of predator recognition for woodfrog tadpoles exposed to novel trout predators. Tadpoles conditioned to recognize tiger trout, a hybrid derived from brown trout and brook trout, showed generalization of recognition of several unknown trout odours. Interestingly, the tadpoles showed stronger responses to odours of brown trout than brook trout. In a second experiment, we found that tadpoles trained to recognize brown trout showed stronger responses to tiger trout than those tadpoles trained to recognize brook trout. Given that tiger trout always have a brown trout mother and a brook trout father, these results suggest a strong maternal signature in trout odours. Tadpoles that were trained to recognize both brown trout and brook trout showed stronger response to novel tiger trout than those trained to recognize only brown trout or only brook trout. This is consistent with a peak shift in recognition, whereby cues that are intermediate between two known cues evoke stronger responses than either known cue. Given that our woodfrog tadpoles have no evolutionary or individual experience with trout, they have no way of knowing whether or not brook trout, brown trout or tiger trout are more dangerous. The differential intensity of responses that we observed to hybrid trout cues and each of the parental species indicates that there is a likely mismatch between risk and anti-predator response intensity. Future work needs to address the critical role of prey naivety on responses to invasive and introduced hybrid predators.
Elevational differences in developmental plasticity determine phenological responses of grasshoppers to recent climate warming
Authors: Buckley Lauren B. , Nufio César R. , Kirk Evan M. , Kingsolver Joel G.
Published: June 2015

Annual species may increase reproduction by increasing adult body size through extended development, but risk being unable to complete development in seasonally limited environments. Synthetic reviews indicate that most, but not all, species have responded to recent climate warming by advancing the seasonal timing of adult emergence or reproduction. Here, we show that 50 years of climate change have delayed development in high-elevation, season-limited grasshopper populations, but advanced development in populations at lower elevations. Developmental delays are most pronounced for early-season species, which might benefit most from delaying development when released from seasonal time constraints. Rearing experiments confirm that population, elevation and temperature interact to determine development time. Population differences in developmental plasticity may account for variability in phenological shifts among adults. An integrated consideration of the full life cycle that considers local adaptation and plasticity may be essential for understanding and predicting responses to climate change.
The role of ontogeny in physiological tolerance: decreasing hydrostatic pressure tolerance with development in the northern stone crabLithodes maja
Authors: Munro Catriona , Morris James P. , Brown Alastair , Hauton Chris , Thatje Sven
Published: June 2015

Extant deep-sea invertebrate fauna represent both ancient and recent invasions from shallow-water habitats. Hydrostatic pressure may present a significant physiological challenge to organisms seeking to colonize deeper waters or migrate ontogenetically. Pressure may be a key factor contributing to bottlenecks in the radiation of taxa and potentially drive speciation. Here, we assess shifts in the tolerance of hydrostatic pressure through early ontogeny of the northern stone crabLithodes maja, which occupies a depth range of 4–790 m in the North Atlantic. The zoea I, megalopa and crab I stages were exposed to hydrostatic pressures up to 30.0 MPa (equivalent of 3000 m depth), and the relative fold change of genes putatively coding for theN-methyl-d-aspartate receptor-regulated protein 1 (narggene), two heat-shock protein 70 kDa (HSP70) isoforms and mitochondrial Citrate Synthase (CSgene) were measured. This study finds a significant increase in the relative expression of theCSandhsp70agenes with increased hydrostatic pressure in the zoea I stage, and an increase in the relative expression of all genes with increased hydrostatic pressure in the megalopa and crab I stages. Transcriptional responses are corroborated by patterns in respiratory rates in response to hydrostatic pressure in all stages. These results suggest a decrease in the acute high-pressure tolerance limit as ontogeny advances, as reflected by a shift in the hydrostatic pressure at which significant differences are observed.
Crying wolf to a predator: deceptive vocal mimicry by a bird protecting young
Authors: Igic Branislav , McLachlan Jessica , Lehtinen Inkeri , Magrath Robert D.
Published: June 2015

Animals often mimic dangerous or toxic species to deter predators; however, mimicry of such species may not always be possible and mimicry of benign species seems unlikely to confer anti-predator benefits. We reveal a system in which a bird mimics the alarm calls of harmless species to fool a predator 40 times its size and protect its offspring against attack. Our experiments revealed that brown thornbills (Acanthiza pusilla) mimic a chorus of other species' aerial alarm calls, a cue of anAccipiterhawk in flight, when predators attack their nest. The absence of any flying predators in this context implies that these alarms convey deceptive information about the type of danger present. Experiments on the primary nest predators of thornbills, pied currawongs (Strepera graculina), revealed that the predators treat these alarms as if they themselves are threatened by flying hawks, either by scanning the sky for danger or fleeing, confirming a deceptive function. In turn, these distractions delay attack and provide thornbill nestlings with an opportunity to escape. This sophisticated defence strategy exploits the complex web of interactions among multiple species across several trophic levels, and in particular exploits a predator's ability to eavesdrop on and respond appropriately to heterospecific alarm calls. Our findings demonstrate that prey can fool predators by deceptively mimicking alarm calls of harmless species, suggesting that defensive mimicry could be more widespread because of indirect effects on predators within a web of eavesdropping.
Cognitive ability is heritable and predicts the success of an alternative mating tactic
Authors: Smith Carl , Philips André , Reichard Martin
Published: June 2015

The ability to attract mates, acquire resources for reproduction, and successfully outcompete rivals for fertilizations may make demands on cognitive traits—the mechanisms by which an animal acquires, processes, stores and acts upon information from its environment. Consequently, cognitive traits potentially undergo sexual selection in some mating systems. We investigated the role of cognitive traits on the reproductive performance of male rose bitterling (
Rhodeus ocellatus
), a freshwater fish with a complex mating system and alternative mating tactics. We quantified the learning accuracy of males and females in a spatial learning task and scored them for learning accuracy. Males were subsequently allowed to play the roles of a guarder and a sneaker in competitive mating trials, with reproductive success measured using paternity analysis. We detected a significant interaction between male mating role and learning accuracy on reproductive success, with the best-performing males in maze trials showing greater reproductive success in a sneaker role than as a guarder. Using a cross-classified breeding design, learning accuracy was demonstrated to be heritable, with significant additive maternal and paternal effects. Our results imply that male cognitive traits may undergo intra-sexual selection.
The weighting is the hardest part: on the behavior of the likelihood ratio test and score test under weight misspecification in rare variant association studies
Authors: Minică Camelia C. , Genovese Giulio , Hultman Christina M. , Pool René , Vink Jacqueline M. , Dolan Conor V. , Neale Benjamin M.
Published: June 2015

Rare variant association studies are at a critical inflexion point with the increasing availability of exome-sequencing data. A popular test of association is the sequence kernel association test (SKAT). Weights are embedded within SKAT to reflect the hypothesized contribution of the variants to the trait variance. Correct weighting is expected to boost power, and yet the correct weights are generally unknown. It is therefore important to assess the effect of weight misspecification in SKAT.

We evaluated the behavior of the score and likelihood ratio tests (LRT) under weight misspecification. Simulation and empirical results revealed that LRT is generally more robust and more powerful than score test in such a circumstance. For instance, when the simulated betas were larger for rarer than for more common variants, (incorrectly) assigning equal weights reduced the power of the LRT by ∼ 5%, while the score test’s power dropped by ∼ 30%.

To optimize weighting we proposed a data-driven weighting scheme. With this scheme and LRT we detected significant enrichment of rare case mutations (MAF<5%; P-value=7e-04) of a set of constrained genes in the Swedish schizophre-nia case-control cohort with exome-sequencing data.

The score test is currently preferred for its computational efficiency and power. Indeed, assuming correct specification, in some circumstances the score test is the most powerful test. However, LRT has the compelling qualities of being generally more powerful and more robust to misspecification. This is an important result given that, arguably, misspecified models are likely to be the rule rather than the exception in weighting-based approaches.
Sequence capture of ultraconserved elements from bird museum specimens
Authors: McCormack John E. , Tsai Whitney L.E. , Faircloth Brant C.
Published: June 2015

New DNA sequencing technologies are allowing researchers to explore the genomes of the millions of natural history specimens collected prior to the molecular era. Yet, we know little about how well specific next-generation sequencing (NGS) techniques work with the degraded DNA typically extracted from museum specimens. Here, we use one type of NGS approach, sequence capture of ultraconserved elements (UCEs), to collect data from bird museum specimens as old as 120 years. We targeted approximately 5,000 UCE loci in 27 Western Scrub-Jays (Aphelocoma californica) representing three evolutionary lineages, and we collected an average of 3,749 UCE loci containing 4,460 single nucleotide polymorphisms (SNPs). Despite older specimens producing fewer and shorter loci in general, we collected thousands of markers from even the oldest specimens. More sequencing reads per individual helped to boost the number of UCE loci we recovered from older specimens, but more sequencing was not as successful at increasing the length of loci. We detected contamination in some samples and determined contamination was more prevalent in older samples that were subject to less sequencing. For the phylogeny generated from concatenated UCE loci, contamination led to incorrect placement of some individuals. In contrast, a species tree constructed from SNPs called within UCE loci correctly placed individuals into three monophyletic groups, perhaps because of the stricter analytical procedures we used for SNP calling. This study and other recent studies on the genomics of museums specimens have profound implications for natural history collections, where millions of older specimens should now be considered genomic resources.
The next 20 years of genome research
Authors: Schatz Michael C.
Published: June 2015

The last 20 years have been a remarkable era for biology and medicine. One of the most significant achievements has been the sequencing of the first human genomes, which has laid the foundation for profound insights into human genetics, the intricacies of regulation and development, and the forces of evolution. Incredibly, as we look into the future over the next 20 years, we see the very real potential for sequencing more than one billion genomes, bringing with it even deeper insights into human genetics as well as the genetics of millions of other species on the planet. Realizing this great potential, though, will only be achieved through the integration and development of highly scalable computational and quantitative approaches can keep pace with the rapid improvements to biotechnology. In this perspective, we aim to chart out these future technologies, anticipate the major themes of research, and call out the challenges ahead. One of the largest shifts will be in the training used to prepare the class of 2035 for their highly interdisciplinary world.
Myc-induced cell mixing is required for competitive tissue invasion and destruction
Authors: Moreno Eduardo , Levayer Romain , Hauert Barbara
Published: June 2015

Cell-cell intercalation is used in several developmental processes to shape the normal body plan1. There is no clear evidence that intercalation is involved in pathologies. Here, we use the proto-oncogene Myc to study a process analogous to early phase of tumour expansion: Myc-induced cell competition2-7. Cell competition is a conserved mechanism5,6,8,9 driving the elimination of slow proliferating cells (so called losers) by faster proliferating neighbours (so called winners) through apoptosis10 and is important to prevent developmental malformations and maintain tissue fitness11. Using long term live imaging of Myc-driven competition in the Drosophila pupal notum and in the wing imaginal disc, we show that the probability of elimination of loser cells correlates with the surface of contact shared with winners. As such, modifying loser/winner interface morphology can modulate the strength of competition. We further show that elimination of loser clones requires winner/loser cell mixing through cell-cell intercalation. Cell mixing is driven by differential growth and the high tension at winner-winner interfaces relative to winner-loser and loser-loser interfaces, which leads to a preferential stabilisation of winner-loser contacts and reduction of clone compactness over time. Differences in tension are generated by a relative difference of junctional F-actin levels between loser and winner junctions, induced by differential levels of the phosphatidylinositol PIP3. Our results establish the first link between cell-cell intercalation induced by a proto-oncogene and how it promotes invasiveness and destruction of healthy tissues.
Impact of China’s cooperation: the case of Chinese garages in Tanzania
Authors: Kinyondo Godbertha , Chatama Yuda Julius
Published: June 2015

Purpose

– The purpose of this paper was to investigate China ' s motive for its relations with Africa. Within that broad framework, the paper investigates China–Tanzania cooperation from an economic and social development perspective. It analyses the status of Chinese investments and, more specifically, it focuses on the increasing numbers of Chinese garages and assesses whether they have positive spill-over towards achievement of sustainable development.

Design/methodology/approach

– Case study was used; it involves an up-close, in-depth and detailed examination of the growth of Chinese garages in Tanzania, as well as its related contextual conditions including the overall impact of foreign direct investment (FDI) on the vehicle repair sector in Tanzania. Scholarly works from various sources including researchers as well as authoritative reports were consulted.

Findings

– The paper shows that there is an increase in Chinese garage investment which has brought significant benefits such as technology spill-over, increased employment albeit at low-level pay as well as functioning as a stimulus for Tanzanian self-employment.

Practical implications

– A free market environment which attracts significant FDI including Chinese garages should be strengthened. Chinese garages should not employ Chinese when there are Tanzanians with required expertise. Further research on the long history of relations between Tanzania and Scandinavian countries is better for comparison.

Originality/value

– The paper presents original findings based on scholarly work related to the growth of Chinese garage investments in Tanzania.
Till stress do us part: the causes and consequences of expatriate divorce
Authors: McNulty Yvonne
Published: June 2015

Purpose

– International relocation is undoubtedly a source of stress for families, and in particular for married couples. Yet, despite familial challenges and the fact that “family concerns” remain a top reason for assignment refusal and assignment failure, including a growing body of anecdotal evidence suggesting that many expatriate marriages fail often at huge cost to organizations, there is not one academic study yet published on expatriate divorce. The purpose of this paper is to empirically examine the causes and consequences of expatriate divorce.

Design/methodology/approach

– In this exploratory case-based study, the author uses respondent data from 13 face-to-face interviews and 25 online survey participants.

Findings

– Findings demonstrate that expatriate marriages end in divorce for two main reasons: first, a core issue in the marriage that exists before going abroad (e.g. alcoholism, mental health problems) and which continues while abroad; and second, when one or both spouses is negatively influenced by an expatriate culture to such an extent that a form of “group think” results in polarizing behavior that is counter to how they might behave “back home” (e.g. infidelity, sexual misconduct). The consequences of divorce for expatriates are immense and include bankruptcy, destitution, homelessness, depression, psychophysiological illness, alienation from children, and suicide.

Research limitations/implications

– Data are cross-sectional and findings are limited by single-response bias. Future studies would do well to research matched samples of couples engaging in global work experiences over different points in time in order to track longitudinal changes in marital quality, including why some go on to divorce while others recover from marital breakdown and stay married.

Practical implications

– One of the strongest pieces of advice offered by most of the respondents is for spouses, and trailing spouses in particular, to know their legal rights and entitlements in each country where they are living in the event of divorce.

Originality/value

– This is the first study to empirically explore the lived experience of expatriate divorce.
A qualitative study of older people with minimal care needs experiences of their admission to a nursing home with Registered Nurse care
Authors: Stevens Alice K. , Raphael Helen , Green Sue M.
Published: June 2015

Purpose

– Residential care for older people in the UK includes care homes with and without 24-hour Registered Nurse (RN) care. Reduced autonomy and personal wealth can result when people assessed as having minimal care needs, enter and reside in care homes with RN care. The purpose of this paper is to explore the experiences of older people with minimal care needs admission to care homes with RN care.

Design/methodology/approach

– A qualitative study using a grounded theory method was undertaken. In total, 12 care home with RN care residents assessed as not requiring nursing care were interviewed. Initial sampling was purposive and progressed to theoretical. Interviews were analysed using the grounded theory analysis method of constant comparison and theory development.

Findings

– Two main categories emerged: “choosing the path”, which concerned the decision to enter the home, and “settling in”, which related to adaptation to the environment. Findings suggested participants who perceived they had greater control over the decision-making process found it easier to settle in the care home. The two categories linked to form an emerging framework of “crossing the bridge” from independent living to care home resident.

Research limitations/implications

– The findings contribute to the understanding of factors influencing admission of older people with minimal care needs to care homes with RN care and highlight the importance of informed decision making.

Practical implications

– Health and social care professionals must give informed support and advice to older people seeking care options to ensure their needs are best met.

Originality/value

– This study enabled older people with minimal care needs admission to care homes with RN care to voice their experiences.