bluuebunny/crossref_metadata_2025 huggingface dataset:
Why should we correct reported pulsation frequencies for stellar line-of-sight Doppler velocity shifts?
Authors: Davies G. R. , Handberg R. , Miglio A. , Campante T. L. , Chaplin W. J. , Elsworth Y.
Published: September 2014

In the age of Kepler and CoRoT, extended observations have provided estimates of stellar pulsation frequencies that have achieved new levels of precision, regularly exceeding fractional levels of a few parts in 104. These high levels of precision now in principle exceed the point where one can ignore the Doppler shift of pulsation frequencies caused by the motion of a star relative to the observer. We present a correction for these Doppler shifts and use previously published pulsation frequencies to demonstrate the significance of the effect. We suggest that reported pulsation frequencies should be routinely corrected for stellar line-of-sight velocity Doppler shifts, or if a line-of-sight velocity estimate is not available, the frame of reference in which the frequencies are reported should be clearly stated.
The red supergiant and supernova rate problems: implications for core-collapse supernova physics
Authors: Horiuchi S. , Nakamura K. , Takiwaki T. , Kotake K. , Tanaka M.
Published: September 2014

Mapping supernovae to their progenitors is fundamental to understanding the collapse of massive stars. We investigate the red supergiant problem, which concerns why red supergiants with masses ∼16–30 M⊙ have not been identified as progenitors of Type IIP supernovae, and the supernova rate problem, which concerns why the observed cosmic supernova rate is smaller than the observed cosmic star formation rate. We find key physics to solving these in the compactness parameter, which characterizes the density structure of the progenitor. If massive stars with compactness above ξ2.5 ∼ 0.2 fail to produce canonical supernovae, (i) stars in the mass range 16–30 M⊙ populate an island of stars that have high ξ2.5 and do not produce canonical supernovae, and (ii) the fraction of such stars is consistent with the missing fraction of supernovae relative to star formation. We support this scenario with a series of two- and three-dimensional radiation hydrodynamics core-collapse simulations. Using more than 300 progenitors covering initial masses 10.8–75 M⊙ and three initial metallicities, we show that high compactness is conducive to failed explosions. We then argue that a critical compactness of ∼0.2 as the divide between successful and failed explosions is consistent with state-of-the-art three-dimensional core-collapse simulations. Our study implies that numerical simulations of core collapse need not produce robust explosions in a significant fraction of compact massive star initial conditions.
Historical Range of Variability
Authors: Wohl Ellen
Published: September 2014

Historical range of variability (HRV) describes the conditions of a natural system prior to intensive human alteration of that system. In this context, a natural system can be an ecosystem or a particular component of an ecosystem. Ecosystem components can be quite diverse, including the population of a species or geographic range of a species; an aspect of the disturbance regime, such as the frequency, severity, and spatial extent of wildfire or drought; or physicochemical parameters, such as water chemistry. Regardless of the component to which HRV is applied, the intent is to understand the range of variations in relevant parameters in the absence of human influence on the system. With respect to environmental science, deviations from HRV are taken as evidence of human influence on the system under consideration, and resource management is designed to maintain systems within HRV or within a socially preferred range based on HRV. The concept of HRV was initially developed by ecologists working in North America, and it was applied to understanding ecosystem characteristics prior to European settlement of a region. Although HRV was first mentioned in the early to mid-1990s, the idea of using historical conditions as a reference for ecosystem management goes back much further. HRV built on this earlier work by explicitly considering spatial and temporal variability of system components and processes. Systems exhibit variability through time because conditions change in response to disturbances. The concepts of Disturbance Regime and HRV are thus closely coupled. The assumption underlying HRV is that a system exhibits characteristic behavior and complexity when disturbances occur with a characteristic behavior through time. If human activities alter the disturbance regime, the system changes so as to exceed the bounds described by HRV. HRV is now used by scholars in diverse disciplines, and it is sometimes defined for very different time periods. HRV has been used, for example, to refer to variability during the recent past and intensive human alteration of the system. Consequently, it is important to understand the manner in which HRV is being defined in any particular study. HRV is also referred to as range of natural variability and reference variability. Regardless of the phrase used, the underlying concept represents some of the most fundamental questions we can ask in environmental science: What is the natural range of variability in a system, and in what manner have human activities altered this range?
Adaptation
Authors: Leitch Thomas , Meikle Kyle
Published: September 2014

Studies of cinematic adaptations—films based, as the American Academy of Motion Picture Arts and Sciences puts it, on material originally presented in another medium—are scarcely a century old. Even so, particular studies of adaptation, the process by which texts in a wide range of media are transformed into films (and more recently into other texts that are not necessarily films), cannot be properly understood without reference to the specific period they were produced in. Each generation of adaptation studies has produced its own principles and orthodoxies, typically by attacking the orthodoxies and principles of the preceding generation. Adaptation studies have regularly alternated between polemics that attacked earlier assumptions in the field and readings of individual adaptations that have explored the implications of these attacks and so implicitly established new orthodoxies. The earliest work on adaptation, from Vachel Lindsay’s The Art of the Moving Picture, first published in 1915, to André Bazin’s “Adaptation, or the Cinema as Digest,” first published in 1948, grapples with the general relationship between literature and cinema as presentational modes. The second phase, focusing mostly on adaptations of individual novels to films, follows George Bluestone’s highly influential 2003 study Novels into Film, originally published in 1957, in assuming a series of categorical distinctions between verbal and visual representational modes. Most studies of individual adaptations and their sources, and most textbooks on adaptation, have been produced under the influence of these assumptions. In this third phase, Robert Stam’s 2000 article “Beyond Fidelity: The Dialogics of Adaptation” rejects the binary distinctions between source texts and adaptations; Kamilla Elliott’s 2003 book Rethinking the Novel/Film Debate deconstructs the binary distinctions between verbal and visual texts; and Linda Hutcheon and Siobhan O’Flynn’s 2012 book A Theory of Adaptation emphasizes the continuities between texts that have been explicitly identified as adaptations and all other texts as intertextual palimpsests marked by traces of innumerable earlier texts. This third phase has generated most of the leading work on adaptation theory. An emerging fourth phase is heralded by Jay David Bolter and Richard Grusin’s 1999 study Remediation: Understanding New Media and Lev Manovich’s 2001 book The Language of New Media. Both are inspired by the rise of the digital media that establishes every reader as a potential writer. These analysts use a Wiki-based model of writing as community participation rather than individual creation to break down the distinction between reading and writing and recast adaptation as a quintessential instance of the incessant process of textual production. A leading tendency of this fourth phase has been to use methodologies developed for literature-to-film adaptation to analyze adaptations that range far outside literature and cinema.
African Biomes
Authors: Sinclair Anthony R.E. , Beyers Rene L.
Published: September 2014

Africa has a great diversity of environmental conditions. It is bisected by the equator so that the seasons are six months out of phase north and south of it. There are tropical forests on the west side as well as in the center of the continent. In roughly concentric rings out from the forest, there are progressively drier vegetation types from woodland, savanna, and grassland to desert. There are several major rivers flowing north, west, and east. Africa has also been the center of evolution of many large mammal groups. It has a high diversity of birds and insects. It is also the origin of the human species, and humans have influenced and modified the landscape for hundreds of thousands of years. Humans evolved there over the past four million years. The environment and the biomes that result from it in turn shaped the evolution of humans. Over the Pleistocene (past two million years), the environment swung from warm and wet to cool and dry several times, and consequently the biomes changed in extent from continuous forest (that stretched from the Atlantic to the Indian Ocean) to dry savanna and desert with only small patches of forest in West and Central Africa. These changes that were connected to the ice ages of temperate regions affected human populations. In the past millennium, human numbers have increased and migrations have moved peoples southward through the forests of Central Africa and into eastern and southern Africa. These movements have modified the biomes through grazing pressures on grasslands and agriculture in savanna. In the 20th century, forests were modified through deforestation. Wildlife conservation and ecotourism are prominent in Africa. There are several large protected areas especially in eastern and southern savanna Africa, with some less-known areas of forest reserves. Scientific studies on these protected areas over several decades describe the biology and ecosystem dynamics perhaps better than any other continent. There are scientific syntheses on the Kruger National Park, South Africa, and the Serengeti National Park, Tanzania. Both highlight how the whole ecosystem changes over time with climate change, human population increases, disease outbreaks, and other disturbances. The following sections first cover the vegetation types that are called Biomes; two abiotic environmental factors, climate and fire (Climate Variability and Patterns of Drought and Fire); prominent animal groups characteristic of Africa (Large Mammals, Primates, and Birds); dominant processes such as herbivory, predation, niche partitioning, facilitation, and migration (Herbivory, Predators and Predation, Niche Partitioning, Facilitation, and Migrations); and finally the expansion of human impacts on biomes and the related aspects of traditional livelihoods and conservation (Traditional Human Livelihoods and Conservation). Social and political history also modify human impacts but are not covered in this review.
Goal-direction and top-down control
Authors: Buschman Timothy J. , Miller Earl K.
Published: September 2014

We review the neural mechanisms that support top-down control of behaviour and suggest that goal-directed behaviour uses two systems that work in concert. A basal ganglia-centred system quickly learns simple, fixed goal-directed behaviours while a prefrontal cortex-centred system gradually learns more complex (abstract or long-term) goal-directed behaviours. Interactions between these two systems allow top-down control mechanisms to learn how to direct behaviour towards a goal but also how to guide behaviour when faced with a novel situation.
The algorithmic anatomy of model-based evaluation
Authors: Daw Nathaniel D. , Dayan Peter
Published: September 2014

Despite many debates in the first half of the twentieth century, it is now largely a truism that humans and other animals build models of their environments and use them for prediction and control. However, model-based (MB) reasoning presents severe computational challenges. Alternative, computationally simpler, model-free (MF) schemes have been suggested in the reinforcement learning literature, and have afforded influential accounts of behavioural and neural data. Here, we study the realization of MB calculations, and the ways that this might be woven together with MF values and evaluation methods. There are as yet mostly only hints in the literature as to the resulting tapestry, so we offer more preview than review.
Gene regulatory network inference from perturbed time-series expression data via ordered dynamical expansion of non-steady state actors
Authors: Zamanighomi Mahdi , Zamanian Mostafa , Kimber Michael J , Wang Zhengdao
Published: September 2014

The reconstruction of gene regulatory networks from gene expression data has been the subject of intense research activity. A variety of models and methods have been developed to address different aspects of this important problem. However, these techniques are often difficult to scale, are narrowly focused on particular biological and experimental platforms, and require experimental data that are typically unavailable and difficult to ascertain. The more recent availability of higher-throughput sequencing platforms, combined with more precise modes of genetic perturbation, present an opportunity to formulate more robust and comprehensive approaches to gene network inference. Here, we propose a step-wise framework for identifying gene-gene regulatory interactions that expand from a known point of genetic or chemical perturbation using time series gene expression data. This novel approach sequentially identifies non-steady state genes post-perturbation and incorporates them into a growing series of low-complexity optimization problems. The governing ordinary differential equations of this model are rooted in the biophysics of stochastic molecular events that underlie gene regulation, delineating roles for both protein and RNA-mediated gene regulation. We show the successful application of our core algorithms for network inference using simulated and real datasets.
On Modeling the Macroecology of Baleen Whale Migration
Authors: Watson James R. , Favetta Bruna , Stock Charles
Published: September 2014

Long distance migrations are well known to occur in many baleen whale species. Yet, a global synthesis of this information is lacking. Here, we study baleen whales as a group and at a global scale, first analyzing the grey and peer-reviewed literature for information on the location of baleen whale calving and feeding grounds around the world. This information was then combined with modeled-data produced from an Earth System Model to estimate the global distribution of baleen whale calving and feeding habitats. A simple network theoretic heuristic was then used to identify the shortest over-water path connecting habitats. These shortest paths map well to known major migration routes for a number of species, suggesting that migration has evolved primarily to minimize travel distances. Identifying distance minimizing routes globally, that have demonstrable consistency to known migration routes for certain baleen whale species, offers a useful baseline perspective on large-scale migration patterns, from which many perturbations can by judged. As an example, we used our modeled migration routes to identify regions of the ocean that are likely hotspots of whale ship-strikes. Such information is useful for developing global conservation and management priorities for baleen whales.
How to make deposition of images a reality
Authors: Guss J. Mitchell , McMahon Brian
Published: September 2014

The IUCr Diffraction Data Deposition Working Group is investigating the rationale and policies for routine deposition of diffraction images (and other primary experimental data sets). An information-management framework is described that should inform policy directions, and some of the technical and other issues that need to be addressed in an effort to achieve such a goal are analysed. In the near future, routine data deposition could be encouraged at one of the growing number of institutional repositories that accept data sets or at a generic data-publishing web repository service. To realise all of the potential benefits of depositing diffraction data, specialized archives would be preferable. Funding such an initiative will be challenging.
Operation of the Australian Store.Synchrotron for macromolecular crystallography
Authors: Meyer Grischa R. , Aragão David , Mudie Nathan J. , Caradoc-Davies Tom T. , McGowan Sheena , Bertling Philip J. , Groenewegen David , Quenette Stevan M. , Bond Charles S. , Buckle Ashley M. , Androulakis Steve
Published: September 2014

The Store.Synchrotron service, a fully functional, cloud computing-based solution to raw X-ray data archiving and dissemination at the Australian Synchrotron, is described. The service automatically receives and archives raw diffraction data, related metadata and preliminary results of automated data-processing workflows. Data are able to be shared with collaborators and opened to the public. In the nine months since its deployment in August 2013, the service has handled over 22.4 TB of raw data (∼1.7 million diffraction images). Several real examples from the Australian crystallographic community are described that illustrate the advantages of the approach, which include real-time online data access and fully redundant, secure storage. Discoveries in biological sciences increasingly require multidisciplinary approaches. With this in mind, Store.Synchrotron has been developed as a component within a greater service that can combine data from other instruments at the Australian Synchrotron, as well as instruments at the Australian neutron source ANSTO. It is therefore envisaged that this will serve as a model implementation of raw data archiving and dissemination within the structural biology research community.
Factors influencing nucleo-cytoplasmic trafficking: which matter? Response to Alvisi & Jans' comment onPhosphorylation adjacent to the nuclear localization signal of human dUTPase abolishes nuclear import: structural and mechanistic insights
Authors: Róna Gergely , Borsos Máté , Kobe Bostjan , Vértessy Beáta G.
Published: September 2014

The authors respond to a comment by Alvisi & Jans [(2014),Acta Cryst.D70, 2775–2776] on the articlePhosphorylation adjacent to the nuclear localization signal of human dUTPase abolishes nuclear import: structural and mechanistic insights[Rónaet al.(2013),Acta Cryst.D69, 2495–2505].
Response toOn prompt update of literature references in the Protein Data Bank
Authors: Berman Helen M. , Burley Stephen K. , Kleywegt Gerard J. , Nakamura Haruki , Markley John L.
Published: September 2014

The wwPDB responds to the articleOn the prompt update of literature references in the Protein Data Bank[Wlodawer (2014),Acta Cryst.D70, 2779].
Crystal structure of (2,11-diaza[3.3](2,6)pyridinophane-κ4N,N′,N′′,N′′′)(1,6,7,12-tetraazaperylene-κ2N1,N12)ruthenium(II) bis(hexafluoridophosphate) acetonitrile 1.422-solvate
Authors: Brietzke Thomas , Rottke Falko Otto , Kelling Alexandra , Schilde Uwe , Holdt Hans-Jürgen
Published: September 2014

In the title compound, [Ru(C14H16N4)(C16H8N4)](PF6)2·1.422CH3CN, discrete dimers of complex cations, [Ru(L–N4H2)tape]2+are formed {L–N4H2= 2,11-diaza[3.3](2,6)pyridinophane; tape = 1,6,7,12-tetraazaperylene}, held together by π–π stacking interactionsviathe tape ligand moieties with a centroid–centroid distance of 3.49 (2) Å, assisted by hydrogen bonds between the non-coordinating tape ligand α,α′-diimine unit and the amine proton of a 2,11-diaza[3.3](2,6)-pyridinophane ligand of the opposite complex cation. The combination of these interactions leads to an unusual nearly face-to-face π–π stacking mode. Additional weak C—H...N, C—H...F, N—H...F and P—F...π-ring (tape, py) (with F...centroid distances of 2.925–3.984 Å) interactions are found, leading to a three-dimensional architecture. The RuIIatom is coordinated in a distorted octahedral geometry, particularly manifested by the Namine—Ru—Namineangle of 153.79 (10)°. The counter-charge is provided by two hexafluoridophosphate anions and the asymmetric unit is completed by acetonitrile solvent molecules of crystallization. Disorder was observed for both the hexafluoridophosphate anions as well as the acetonitrile solvate molecules, with occupancies for the major moieties of 0.801 (6) for one of the PF6anions, and a shared occupancy of 0.9215 (17) for the second PF6anion and a partially occupied acetonitrile molecule. A second CH3CN molecule is fully occupied, but 1:1 disordered across a crystallographic inversion center.
Crystal structure of bis(4-allyl-2-methoxyphenyl) terephthalate
Authors: Kang Sung Kwon , Han Byung Hee
Published: September 2014

The asymmetric unit of the title compound, C28H26O6, contains one half-molecule, with the complete molecule generated by a crystallographic inversion center. The central terephthalate and methoxybenzene rings are approximately perpendicular, making a dihedral angle of 80.31 (5)°. No specific directional contacts are noted in the crystal packing. The terminal vinyl group is disordered over two orientations with an occupancy ratio of 0.796 (4):0.204 (4).
Crystal structure of triphenyl(vinyl)phosphonium tetraphenylborate
Authors: Bradfield Joseph L. , Braun Richard A. , White Frankie , Hendrich Jeffrey M. , Sykora Richard E. , Mirjafari Arsalan
Published: September 2014

The title ionic salt, C21H20P+·C24H20B−, crystallized with two independent vinyltriphenylphosphonium cations and two independent tetraphenylborate anions per asymmetric unit. These four independent moieties contain nearly perfect tetrahedral symmetry about their respective central C atoms. In the crystal, there are no π-stacking or other intermolecular interactions present.
Path degeneracy and EXAFS analysis of disordered materials
Authors: Ravel Bruce
Published: September 2014

Analysis of EXAFS data measured on a material with a disordered local configuration environment around the absorbing atom can be challenging owing to the proliferation of photoelectron scattering paths that must be considered in the analysis. In the case where the absorbing atom exists in multiple inequivalent sites, the problem is compounded by having to consider each site separately. A method is proposed for automating the calculation of theory for inequivalent sites, then averaging the contributions from sufficiently similar scattering paths. With this approach, the complexity of implementing a successful fitting model on a highly disordered sample is reduced. As an example, an analysis of TiK-edge data on zirconolite, CaZrTi2O7, which has three inequivalent Ti sites, is presented.
Injection pressure and velocity of impact-driven liquid jets
Authors: Seehanam Wirapan , Pianthong Kulachate , Sittiwong Wuttichai , Milton Brian
Published: September 2014

Purpose

– The purpose of this paper is to describe a procedure to simulate impact-driven liquid jets by computational fluid dynamics (CFD). The proposed CFD model is used to investigate nozzle flow behavior under ultra-high injection pressure and jet velocities generated by the impact driven method (IDM).

Design/methodology/approach

– A CFD technique was employed to simulate the jet generation process. The injection process was simulated by using a two-phase flow mixture model, while the projectile motion was modeled the moving mesh technique. CFD results were compared with experimental results from jets generated by the IDM.

Findings

– The paper provides a procedure to simulate impact-driven liquid jets by CFD. The validation shows reasonable agreement to previous experimental results. The pressure fluctuations inside the nozzle cavity strongly affect the liquid jet formation. The average jet velocity and the injection pressure depends mainly on the impact momentum and the volume of liquid in the nozzle, while the nozzle flow behavior (pressure fluctuation) depends mainly on the liquid volume and the impact velocity.

Research limitations/implications

– Results may slightly deviate from the actual phenomena due to two assumptions which are the liquid compressibility depends only on the rate of change of pressure respected to the liquid volume and the super cavitation process in the generation process is not taken into account.

Practical implications

– Results from this study will be useful for further designs of the nozzle and impact conditions for applications of jet cutting, jet penetration, needle free injection, or any related areas.

Originality/value

– This study presents the first success of employing a commercial code with additional user defined function to calculate the complex phenomena in the nozzle flow and jet injection generated by the IDM.
Numerical investigation of magnetic field inclination angle on transient natural convection in an enclosure filled with nanofluid
Authors: Kharati Koopaee Masoud , Jelodari Iman
Published: September 2014

Purpose

– The objective of present research is to characterize the unsteady thermal behavior of a square enclosure filled with water-Al2O3 nanofluids in the presence of oriented magnetic fields. The purpose this paper is to study the effect of pertinent parameters on the transient natural convection in the enclosure.

Design/methodology/approach

– In this research, an in-house implicit finite volume code based on the SIMPLE algorithm is utilized for numerical calculations. To ensure the accuracy of results, comparisons are also made with previous works in literature. In this study, a constant strength magnetic field is concerned and for Rayleigh numbers of Ra=103, 104 and 105 the effect of magnetic field orientation with respect to the case of zero inclination on the thermal performance of cavity is investigated at Hartmann number range of Ha=15-90. In the present work, the nano-particle volume fractions range from φ=0-0.06.

Findings

– Results show that when Rayleigh number is Ra=103, the inclination angle, solid particles and Hartmann number has no effect on the transient behavior. It is shown that during the time advancement to steady condition, the heat transfer rate relative to zero inclination angle, may reach to a maximum value. This relative maximum heat transfer increases as the inclination angle increases and decreases as the solid volume fraction increases. The effect of increase in Hartmann number is to decrease this maximum value at Rayleigh number of Ra=104 and at Rayleigh number of Ra=105, depending on the Hartmann number, this value may increase or decrease. It is also found that an increase in Hartmann number leads to delay the appearance of the relative maximum value of heat transfer. Results show that this maximum value is of more significance at zero solid volume fraction when inclination angle is 90 degrees and Hartmann number is Ha=60.

Originality/value

– Limited works could be found in the literature regarding the idea of using nanofluids as the working fluid in an enclosure in the presence of magnetic field. In these works, the steady state thermal behavior of enclosures subjected to fixed magnetic fields is concerned. In the present work, the unsteady thermal behavior is concerned and the effect of magnetic field orientation angles on transient heat transfer performance of the enclosure at different Rayleigh and Hartmann numbers and solid volume fractions is explored.
Incubator policy to support entrepreneurial development, technology transfer and commercialization
Authors: Wonglimpiyarat Jarunee
Published: September 2014

Purpose

– The purpose of this paper is to study the incubator policy to support entrepreneurial development. In particular, the study reviews the incubation programs and strategies of technology transfer and commercialization as well as the innovation policies to support innovation commercialization in Thailand, based on the Triple Helix model.

Design/methodology/approach

– This study employs the use of case study methodology to understand in-depth the operations of major university business incubators (UBIs) and technology business incubators in enhancing the process of technology commercialization. The study examines case studies of leading UBIs (Mahidol University, Chulalongkorn University and King Mongkut's University of Technology Thonburi) and science and technology incubators of the National Science and Technology Agency (NSTDA) and the National Innovation Agency (NIA). The operations and incubating policies are analyzed through the lens of Triple Helix model. The interviews were carried out using the semi-structured questionnaire to understand the views of trilateral parties (the government, university and industry) related to the concept of Triple Helix model. The interviews were carried out with major stakeholders including policy makers, policy analysts, government officials, managers running incubators, incubates, university professors, research managers. Interview data were supported by an examination of secondary data so as to provide a cross check on internal validity.

Findings

– The results have shown that the incubation program is one of the major policy mechanisms to support innovation and suggested that UBIs should act as an intermediary between the spheres of university and industry to provide interactive linkages and promote effective utilization of university research. The empirical study provides insightful implications on the move toward the entrepreneurial university and the dynamics of the Triple Helix system in stimulating innovation development and diffusion.

Originality/value

– By focussing on the major UBIs and technology business incubators in one of the Asian Tigers – Thailand, the study offers the model of university technology commercialization which could be applied to other developing economies. The study provides useful lessons and insights on the process of technology transfer and commercialization through the university incubation mechanism (university technology commercialization).
REVIEW: On the Front Line: frontal zones as priority at‐sea conservation areas for mobile marine vertebrates
Authors: Scales Kylie L. , Miller Peter I. , Hawkes Lucy A. , Ingram Simon N. , Sims David W. , Votier Stephen C.
Published: September 2014

Identifying priority areas for marine vertebrate conservation is complex because species of conservation concern are highly mobile, inhabit dynamic habitats and are difficult to monitor.

Many marine vertebrates are known to associate with oceanographic fronts – physical interfaces at the transition between water masses – for foraging and migration, making them important candidate sites for conservation. Here, we review associations between marine vertebrates and fronts and how they vary with scale, regional oceanography and foraging ecology.

Accessibility, spatiotemporal predictability and relative productivity of front‐associated foraging habitats are key aspects of their ecological importance. Predictable mesoscale (10s–100s km) regions of persistent frontal activity (‘frontal zones’) are particularly significant.

Frontal zones are hotspots of overlap between critical habitat and spatially explicit anthropogenic threats, such as the concentration of fisheries activity. As such, they represent tractable conservation units, in which to target measures for threat mitigation.

Front mapping via Earth observation (EO) remote sensing facilitates identification and monitoring of these hotspots of vulnerability. Seasonal or climatological products can locate biophysical hotspots, while near‐real‐time front mapping augments the suite of tools supporting spatially dynamic ocean management.

Synthesis and applications. Frontal zones are ecologically important for mobile marine vertebrates. We surmise that relative accessibility, predictability and productivity are key biophysical characteristics of ecologically significant frontal zones in contrasting oceanographic regions. Persistent frontal zones are potential priority conservation areas for multiple marine vertebrate taxa and are easily identifiable through front mapping via EO remote sensing. These insights are useful for marine spatial planning and marine biodiversity conservation, both within Exclusive Economic Zones and in the open oceans.
Retrospective study of metachronous lung metastases from primary hepatocellular carcinoma
Authors: Chok Kenneth S. H. , Yau Thomas C. C. , Cheung Tan To , Poon Ronnie T. P. , Lo Chung Mau
Published: September 2014

Background

This study investigates whether there has been any survival improvement for hepatocellular carcinoma patients with resectable and unresectable lung metastases over time.

Methods

The data of 280 hepatocellular carcinoma patients who developed metachronous lung metastases after hepatectomy with curative intent were analysed. Overall survival was compared in patients with resectable and unresectable lung metastases and in different periods (Era I: 1989–1995, Era II: 1996–2010).

Results

The median overall survival of patients with unresectable and resectable diseases was 7.46 and 40.36 months, respectively (P < 0.0001). In Era I, the median overall survival of patients with unresectable and resectable diseases was 5.59 and 43.15 months, respectively (P < 0.0001). The corresponding figures in Era II were 8.38 and 32.90 months (P < 0.0001). The overall survival of patients with resectable disease did not differ significantly in the two eras but there was a significant improvement in survival of patients with unresectable disease in Era II. Their 1‐year, 3‐year and 5‐year survival rates in Era I versus Era II were 11.1% versus 38.4%, 5.6% versus 9.1% and 2.8% versus 3.5%, respectively (P = 0.041). The corresponding figures for their counterparts in the resectable group were 90% versus 85.8%, 80% versus 45.9% and 40% versus 29.5%, respectively (P = 0.443).

Conclusions

Patients with resectable lung metastases had better overall survival than those with unresectable lung metastases. Notably, patients with unresectable lung metastases had significant improvement in survival over the years.
Acts of Desertion: Abandonment and Renouncement at the Sonoran Borderzone
Authors: Squire Vicki
Published: September 2014

What are ‘acts of desertion’, how do they feature in contemporary border struggles, and what might an emphasis on such acts bring to the analysis of the politics of mobility? This article seeks to address these questions in the context of the Sonoran borderzone, which crosses Mexico and the US. It develops an analysis that sheds light on contemporary border struggles in terms that acknowledge both the intensity of security practices as well as the significance of migratory acts, without pre‐fixing the relation between the two. The analysis shows how ‘acts of desertion’ involve differentiated dynamics of abandonment and renouncement, which demand appreciation of the ambiguities of contemporary border struggles. As acts that variously involve a dynamics of refusal, the article argues that acts of desertion challenge the limits of liberal citizenship, without wholly transcending its limitations.
1 Diversity, Resiliency, and IHOPE‐Maya: Using the Past to Inform the Present
Authors: Chase Arlen F. , Scarborough Vernon
Published: September 2014

How can the past inform the present? Archaeologists working though IHOPE‐Maya seek to address this question by using archaeological data and ecological reconstructions to explore human–nature couplings. Maya archaeologists are revitalizing and contemporizing the field to focus on issues relevant today: the socio‐natural boundary and the coupled human–nature dynamic. The ancient Maya occupied a diverse range of tropical environments that permits a comparative exploration of past permutations in adaptive responses and may also be instructive concerning issues of overexploitation. The variety of places that the Maya occupied afforded diverse opportunities and constraints. By providing access to long‐term historical interactions between peoples and their landscapes, archaeology is uniquely qualified to define, examine, and interpret topics like sustainability, resilience, and vulnerability that are as equally significant to the past as they are to the present. Because Maya archaeology is well positioned to analyze ancient variability in political structures and cultural adaptations that can be related to differential societal success and decline, the discipline can contribute to broader, more current, debates concerning climate change, population limits, urban forms, landscape modifications, and stability. The research being undertaken by IHOPE‐Maya hopes to serve as a catalyst for transforming the field.
5 Ancient Climate and Archaeology: Uxmal, Chichén Itzá, and Their Collapse at the End of the Terminal Classic Period
Authors: Cobos Rafael , de Anda Alanís Guillermo , Moll Roberto García
Published: September 2014

Archaeological data and evidence of climatic change are used to suggest that the collapse of Uxmal and Chichén Itzá in the Northern Maya Lowlands was the result of long and recurrent drought episodes in the eleventh century. Although environmental evidence indicates that drought episodes might have begun in the ninth century, they gradually increased in frequency through the eleventh century and generated devastating effects on the late Terminal Classic period civilization. Evidence of recurrent drought episodes in the Northern lowlands is reported from the Holtún Cenote at Chichén Itzá. This cenote (sinkhole) shows two moments of the climatic change that affected Northern Yucatán. First, it corroborates the existence of extreme dry environmental conditions during the Terminal Classic period dated between the ninth and eleventh centuries. Second, after C.E. 1100, the water level rose inside the Holtún Cenote when environmental conditions turned wetter at the beginning of the Postclassic period.
Differences in multiple‐target visual search performance between non‐professional and professional searchers due to decision‐making criteria
Authors: Biggs Adam T. , Mitroff Stephen R.
Published: September 2014

Professional visual searches, such as those conducted by airport security personnel, often demand highly accurate performance. As many factors can hinder accuracy, it is critical to understand the potential influences. Here, we examined how explicit decision‐making criteria might affect multiple‐target search performance. Non‐professional searchers (college undergraduates) and professional searchers (airport security officers) classified trials as ‘safe’ or ‘dangerous’, in one of two conditions. Those in the ‘one = dangerous’ condition classified trials as dangerous if they found one or two targets, and those in the ‘one = safe’ condition only classified trials as dangerous if they found two targets. The data suggest an important role of context that may be mediated by experience; non‐professional searchers were more likely to miss a second target in the one = dangerous condition (i.e., when finding a second found target did not change the classification), whereas professional searchers were more likely to miss a second in the one = safe condition.
Perioperative use of non‐steroidal anti‐inflammatory drugs might impair dental implant osseointegration
Authors: Winnett Brent , Tenenbaum Howard C. , Ganss Ben , Jokstad Asbjørn
Published: September 2014

Objective

To appraise whether adverse biological events following oral implant placement may be associated with perioperative use of non‐steroidal anti‐inflammatory drugs (NSAIDs).

Methods

All patients treated in a university faculty postgraduate dental clinic between 1979 and 2012 that had experienced a failing and surgically removed dental implant (292 implants in 168 patients) were contacted to solicit additional information about their present dental and medical status and frequency of current and past use of NSAIDs. Potential associations between perioperative NSAIDs use and the occurrence of adverse biological events were explored by the use of 2 × 2 tables and two‐tailed Fisher's exact tests.

Results

One hundred and four patients with initially 468 implants had experienced 238 implant failures, of which 197 were due to failing osseointegration (42%). Sixty of the participants, initially with 273 implants, had used NSAIDs perioperatively and experienced 44% implant failures, versus 38% in the non‐NSAID cohort. The NSAID cohort experienced 3.2 times more cases of radiographic bone loss greater than 30% of the vertical height of their remaining implants and 1.9 times more cases of cluster failures, defined as failure of 50% or more of the implant(s) placed.

Conclusions

Notwithstanding that a retrospective study design is open to potential bias, the current data indicate that dental implant osseointegration may be affected negatively by an inhibitory effect of NSAIDs on bone healing in vulnerable patients. Future and better clinical studies than the current should be designed to appraise more precisely the potential effects of NSAIDs on implant osseointegration in study populations that are not limited by stringent medical inclusion and exclusion criteria.
Locations of acantholysis in pemphigus vulgaris and pemphigus foliaceus
Authors: Ohata Chika , Ishii Norito , Furumura Minao
Published: September 2014

Background

Acantholysis in pemphigus vulgaris (PV) and pemphigus foliaceus (PF) occurs predominantly in the suprabasal area and the granular layer, respectively. However, acantholysis can occasionally be observed in unusual locations.

Methods

We retrospectively studied the acantholysis locations in 35 PV and 27 PF cases, and analyzed them using the index value of Desmoglein (Dsg) 1 and Dsg3 by enzyme‐linked immunosorbent assay, clinical data, and inflammatory cells. We also analyzed the relationship between clinical subtype and various parameters.

Results

In PV, acantholysis was noted in the suprabasal area in 3 cases, in the lower half of the epidermis in 19 cases, and throughout the epidermis in 13 cases. In PF, acantholysis was observed in the granular layer in 6 cases, in the upper half of the epidermis in 14 cases, and throughout the epidermis in 7 cases. Mean index value of Dsg1 in PV patients with acantholysis throughout the epidermis was 2‐fold higher than other PV patients. Neutrophils tended to infiltrate the dermis and epidermis more in PF than in PV.

Conclusions

Higher Dsg1 index values seem to correlate with acantholysis in the upper part of the epidermis in PV. Neutrophils may play some role in unusual acantholysis locations in PF.
The puzzling search for neural correlates of performance
Authors: Brossard‐Racine Marie
Published: September 2014

This commentary is on the original article by Langevin et al. on pages 257–264 of this issue.
Geometric factors influencing the diet of vertebrate predators in marine and terrestrial environments
Authors: Carbone Chris , Codron Daryl , Scofield Conrad , Clauss Marcus , Bielby Jon
Published: September 2014

Predator–prey relationships are vital to ecosystem function and there is a need for greater predictive understanding of these interactions. We develop a geometric foraging model predicting minimum prey size scaling in marine and terrestrial vertebrate predators taking into account habitat dimensionality and biological traits. Our model predicts positive predator–prey size relationships on land but negative relationships in the sea. To test the model, we compiled data on diets of 794 predators (mammals, snakes, sharks and rays). Consistent with predictions, both terrestrial endotherm and ectotherm predators have significantly positive predator–prey size relationships. Marine predators, however, exhibit greater variation. Some of the largest predators specialise on small invertebrates while others are large vertebrate specialists. Prey–predator mass ratios were generally higher for ectothermic than endothermic predators, although dietary patterns were similar. Model‐based simulations of predator–prey relationships were consistent with observed relationships, suggesting that our approach provides insights into both trends and diversity in predator–prey interactions.
Influence of detomidine on atrial fibrillation cycle length measured by intracardiac electrogram recording and by colour tissue Doppler imaging in horses
Authors: Decloedt A. , de Clercq D. , van der Vekens N. , Verheyen T. , Ven S. , van Loon G.
Published: September 2014

Reasons for performing study

Shortening of atrial fibrillation cycle length (AFCL) is a marker of atrial electrical remodelling due to atrial fibrillation (AF).

Objectives

To investigate the effect of administration of detomidine on AFCL measured invasively from an intra‐atrial electrogram (AFCLEGM) and noninvasively by tissue Doppler imaging (AFCLTDI). We hypothesised that detomidine would have no effect on AFCL but would improve the ease of TDI measurements and facilitate noninvasive AFCL determination.

Study design

Prospective clinical study.

Methods

Measurements were performed before and after i.v. administration of 7.5 μg/kg bwt detomidine in 33 episodes of AF in 32 horses (582 ± 64 kg bwt, 10 ± 3 years old) referred for electrical cardioversion. The AFCLEGM was measured from a right atrial intracardiac electrogram. The AFCLTDI was measured from atrial colour tissue velocity curves in 5 atrial wall regions. Mean AFCLEGM and AFCLTDI without and with sedation were compared using a repeated‐measures linear mixed model with Bonferroni correction for multiple comparisons and calculation of the Bland–Altman mean bias and limits of agreement between AFCLEGM and AFCLTDI.

Results

The mean AFCL was significantly increased after sedation, but this increase was very small (mean difference +4 ms). For AFCLTDI measurements, sedation significantly improved the quality of the atrial myocardial velocity curves and the number of AF cycles that could be measured per cardiac cycle. The Bland–Altman bias between AFCLEGM without sedation and AFCLTDI with sedation ranged from ‐18 to +15 ms depending on wall region. Bland–Altman limits of agreement were similar between AFCLEGM without sedation and AFCLTDI without and with sedation. Therefore, noninvasive AFCLTDI measurements with sedation can be used to estimate the atrial fibrillatory rate.

Conclusions

Sedation facilitates noninvasive AFCL measurements but causes a slight increase in AFCL. Noninvasive AFCL measurements can be used as an indicator of atrial electrical remodelling, to study AF pathophysiology and to investigate the effect of anti‐arrhythmic drugs.
Longitudinal changes in infant body composition: association with childhood obesity
Authors: Koontz M. B. , Gunzler D. D. , Presley L. , Catalano P. M.
Published: September 2014

Background

Rapid weight gain in infancy has been established as a risk factor for the development of later obesity.

Objective

We aimed to investigate the role of changes in infant body composition (assessed via total body electrical conductivity) on the development of overweight/obesity in mid‐childhood.

Methods

Fifty‐three term infants were evaluated at birth, three times during infancy and in mid‐childhood. Logistic regression was used to determine associations between rates of total weight gain, fat mass gain and lean mass gain during infancy and later overweight/obesity (defined as body mass index [BMI] ≥85th percentile), adjusted for birth weight and parent education.

Results

At follow‐up (age 9.0 ± 1.8 years), 30% were overweight/obese. More rapid total weight gain from 0 to 4 months was associated with twofold odds (odds ratio [OR] 1.98, 95% confidence interval [CI] 1.05–3.74, P = 0.04) of overweight/obesity in mid‐childhood. From 0 to 8 months, more rapid weight gain was associated with nearly fivefold odds (OR 4.76, 95% CI 1.05–21.5, P = 0.04), and more rapid fat mass gain was associated with eightfold odds (OR 8.03, 95% CI 1.11–58.2, P = 0.04) of later overweight/obesity.

Conclusion

This exploratory study suggests that rapid weight gain, especially fat mass gain, in earlier infancy predisposes to mid‐childhood overweight/obesity.