bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping aortic hemodynamics using 3D cine phase contrast magnetic resonance parallel imaging: Evaluation of an anisotropic diffusion filter
Authors: Tresoldi D. , Cadioli M. , Ponzini R. , Esposito A. , De Cobelli F. , Morbiducci U. , Rizzo G.
Published: June 2013

Purpose

To propose and evaluate an anisotropic diffusion filter to improve visualization and analysis of the thoracic aorta local hemodynamics from phase‐contrast MRI sensitivity encoding imaging.

Methods

The filter parameters were tailored to the phase‐contrast MRI sensitivity encoding data, using a simple calibration procedure. The filter was applied to 20 phase‐contrast MR image studies (five subjects acquired with four different sensitivity encoding reduction factors). The filter effect was estimated with respect to image quality (noise in velocity images, σn), regularity of the velocity fields (divergence; relative error in velocity magnitude, and absolute error in flow direction), aorta flow pattern visualization (streamlines, secondary flows) and flow rate quantification.

Results

σn decreased up to three times, divergence, error in velocity magnitude, and absolute error in flow direction decreased (by at least 313, 40, and 10%, respectively), indicating less noisy and more regular velocity fields after filtering. Streamline analysis confirmed the beneficial effect of anisotropic diffusion filter, both visually and quantitatively (streamline numbers increased by 207% in whole cardiac cycle and by 180% in systolic phase). A high correlation (r = 0.99) between the prefiltering and postfiltering aortic flow rate values was found.

Conclusion

The anisotropic diffusion filter approach can be considered effective in improving the visualization and analysis of the thoracic aorta hemodynamics from phase‐contrast MRI sensitivity encoding images. Magn Reson Med 71:1621–1631, 2014. © 2013 Wiley Periodicals, Inc.
Improvement of blown film extrusion of poly(Lactic Acid): Structure–Processing–Properties relationships
Authors: Mallet Benoit , Lamnawar Khalid , Maazouz Abderrahim
Published: June 2013

The blown extrusion of poly(lactic acid) (PLA) presents several challenges mainly due to the poor shear and elongation properties of this biopolymer. This article highlights some promising routes to enhance the processability of PLA for blown extrusion. To achieve this objective, various formulations of PLA with multifunctionalized epoxy, nucleating agents, and plasticizer were elaborated and studied on the basis of their linear viscoelasticity and elongational properties. We further characterized both the structure and thermomechanical properties of blown films produced with these PLA formulations. Stability charts for the film blowing of neat and modified PLA were thus established at different processing conditions. On the basis of these results, we managed to achieve a large enhancement of the blown processing windows of PLA with high blow‐up ratio (BUR) and take‐up ratio attained. We were able to demonstrate that a higher kinetic of crystallization can also be reached for chain‐extended and branched PLA formulated with adequate amounts of nucleating agents and plasticizers. Induced crystallization during process was also demonstrated. Through this work, blown films with interesting thermomechanical and mechanical properties have been elaborated using an optimal formulation for PLA. POLYM. ENG. SCI., 54:840–857, 2014. © 2013 Society of Plastics Engineers
Recombinant production of TEV cleaved human parathyroid hormone
Authors: Audu Christopher O. , Cochran Jared C. , Pellegrini Maria , Mierke Dale F.
Published: June 2013

The parathyroid hormone, PTH, is responsible for calcium and phosphate ion homeostasis in the body. The first 34 amino acids of the peptide maintain the biological activity of the hormone and is currently marketed for calcium imbalance disorders. Although several methods for the production of recombinant PTH(1‐34) have been reported, most involve the use of cleavage conditions that result in a modified peptide or unfavorable side products. Herein, we detail the recombinant production of 15N‐enriched human parathyroid hormone, 15N PTH(1‐34), generated via a plasmid vector that gives reasonable yield, low‐cost protease cleavage (leaving the native N‐terminal serine in its amino form), and purification by affinity and size exclusion chromatography. We characterize the product by multidimensional, heteronuclear NMR, circular dichroism, and LC/MS. Copyright © 2013 European Peptide Society and John Wiley & Sons, Ltd.
DUSTY PLASMA EFFECTS IN COMETS: EXPECTATIONS FOR ROSETTA
Authors: Mendis D.A. , Horányi M.
Published: June 2013

Despite their small masses, comets have played an extraordinary role in enhancing our understanding of cosmic physics. It was the calculation of comet Halley's orbit and the successful prediction of its return in 1758 that firmly established the correctness of Newton's law of universal gravitation. It was the morphology of the dusty tails of comets that provided the earliest information of the nature of the interaction of solar electromagnetic radiation with dust, and it was the orientation and structure of the plasma tails of comets that led to the discovery of the solar wind. More recently, the role of the changing dusty plasma environments of comets as natural space laboratories for the study of dust‐plasma interactions, and their physical and dynamical consequences, has been recognized. The forthcoming Rosetta‐Philae rendezvous and lander mission will provide a unique opportunity to revisit the entire range of earlier observations of dusty plasma phenomena in a single comet, as it moves around the Sun. In this topical review, motivated by the Rosetta mission, we discuss the varying modes of interaction of the comet as it approaches the Sun, and the different dusty plasma phenomena that are expected in each case, drawing on the earlier observations, including their interpretations and prevailing open questions.
GEOPHYSICAL CHARACTERIZATION OF THE CHICXULUB IMPACT CRATER
Authors: Gulick S.P.S. , Christeson G.L. , Barton P.J. , Grieve R.A.F. , Morgan J.V. , Urrutia‐Fucugauchi J.
Published: June 2013

Geophysical data indicate that the 65.5 million years ago Chicxulub impact structure is a multi‐ring basin, with three sets of semicontinuous, arcuate ring faults and a topographic peak ring (PR). Slump blocks define a terrace zone, which steps down from the inner rim into the annular trough. Fault blocks underlie the PR, which exhibits variable relief, due to target asymmetries. The central structural uplift is >10 km, and the Moho is displaced by 1–2 km. The working hypothesis for the formation of Chicxulub is: a 50 km radius transient cavity, lined with melt and impact breccia, formed within 10 s of the impact, and within minutes, weakened rebounding crust rose kilometers above the surface, the transient crater rim underwent localized deformation and collapsed into large slump blocks, resulting in a inner rim at 70–85 km radius, and outer ring faults at 70–130 km radius. The overheightened structural uplift collapsed outward, buried the inner slump blocks, and formed the PR. Most of the impact melt was ultimately emplaced as a coherent <3 km thick melt sheet within the central basin that shallows within the inner regions of the PR. Smaller pockets of melt flowed into the annular trough. Subsequently, slope collapse, ejecta, ground surge, and tsunami waves infilled the annular trough and annular basin with sediments up to 3 km and 900 m thick, respectively. Testing this working hypothesis requires direct observation of the impactites, within and adjacent to the PR and central basin.
Global warming potentials and radiative efficiencies of halocarbons and related compounds: A comprehensive review
Authors: Hodnebrog Ø. , Etminan M. , Fuglestvedt J. S. , Marston G. , Myhre G. , Nielsen C. J. , Shine K. P. , Wallington T. J.
Published: June 2013

In the mid‐1970s, it was recognized that chlorofluorocarbons (CFCs) were strong greenhouse gases that could have substantial impacts on radiative forcing of climate change, as well as being substances that deplete stratospheric ozone. Around a decade later, this group of radiatively active compounds was expanded to include a large number of replacements for ozone‐depleting substances such as chlorocarbons, hydrochlorocarbons, hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), bromofluorocarbons, and bromochlorofluorocarbons. This paper systematically reviews the published literature concerning the radiative efficiencies (REs) of CFCs, bromofluorocarbons and bromochlorofluorocarbons (halons), HCFCs, HFCs, PFCs, sulfur hexafluoride, nitrogen trifluoride, and related halogen containing compounds. In addition, we provide a comprehensive and self‐consistent set of new calculations of REs and global warming potentials (GWPs) for these compounds, mostly employing atmospheric lifetimes taken from the available literature. We also present global temperature change potentials for selected gases. Infrared absorption spectra used in the RE calculations were taken from databases and individual studies and from experimental and ab initio computational studies. Evaluations of REs and GWPs are presented for more than 200 compounds. Our calculations yield REs significantly (> 5%) different from those in the Intergovernmental Panel on Climate Change Fourth Assessment Report (AR4) for 49 compounds. We present new RE values for more than 100 gases which were not included in AR4. A widely used simple method to calculate REs and GWPs from absorption spectra and atmospheric lifetimes is assessed and updated. This is the most comprehensive review of the radiative efficiencies and global warming potentials of halogenated compounds performed to date.
On some applications of bayesian methods in cancer clinical trials
Authors: Greenhouse Joel B.
Published: June 2013

The NCCTG randomized controlled clinical trial for the treatment of avanced colorectal carcinoma is a wonderful case study of the dynamic interplay between scientific learning and statistical inference. Ethical concerns for minimizing the number of patients assigned to an inferior treatment and interest in identifying subsets of patients for whom a treatment is most likely efficacious pose challenging problems for the practice of statistics. In the first part of this paper, I comment on the applications of Bayesian methods to these problems in the NCCTG trial as presented by Freedman and Spieglehalter and Dixon and Simon, respectively. In the second part of this paper, I discuss and illustrate a Bayesian approach to model sensitivity analysis with a particular focus on model specification and criticism. The Bayesian approach provides a formal methodology to assess the sensitivity of inferences to the inputs into an analysis so that it is possible to investigate the consequences of the specification of the model. I apply these methods to the specification and criticism of a class of survival models for the analysis of survival times in the NCCTG trial.
The correlation between heart period variability and mean period length
Authors: Fleiss J. L. , Bigger J. T. , Rolnitzky L. M.
Published: June 2013

Heart rate variability and heart period variability are important indicators of the functioning of the autonomic nervous system and are strong predictors of survival after myocardial infarction. The standard deviation of a patient's series of normal heart periods (consecutive normal RR intervals) is positively and, in some populations, strongly correlated with the mean period length. This phenomenon has led some investigators to use the coefficient of variation as their measure of variability, because it correlates less strongly with the mean period length. Using data from a multicentre post‐infarction natural history study, we show that the standard deviation of the instantaneous heart rates has, like the coefficient of variation, only a modest correlation with the mean period length. Unlike the coefficient of variation, however, this standard deviation is derivable from established statistical principles. We show further that the coefficient of variation, the standard deviation of heart rates, and the standard deviation of heart periods are approximately equally strong predictors of survival after myocardial infarction.
Bootstraps, permutation tests, and sampling orders of magnitude faster using SAS®
Authors: Opdyke John D. (“J.D.”)
Published: June 2013

While permutation tests and bootstraps have very wide‐ranging application, both share a common potential drawback: as data‐intensive resampling methods, both can be runtime prohibitive when applied to large‐ or even medium‐sized data samples drawn from large datasets. The data explosion over the past few decades has made this a common occurrence, and it highlights the increasing need for faster, and more efficient and scalable, permutation test and bootstrap algorithms. Seven bootstrap and six permutation test algorithms coded in SAS (the largest privately owned software firm globally) are compared herein. The fastest algorithms (‘OPDY’ for the bootstrap, ‘OPDN’ for permutation tests) are new, use no modules beyond Base SAS, and achieve speed increases orders of magnitude faster than the relevant ‘built‐in’ SAS procedures (OPDY is over 200× faster than Proc SurveySelect; OPDN is over 240× faster than Proc SurveySelect, over 350× faster than NPAR1WAY (which crashes on datasets less than a 10th the size OPDN can handle), and over 720× faster than Proc Multtest). OPDY also is much faster than hashing, which crashes on datasets smaller—sometimes by orders of magnitude—than OPDY can handle. OPDY is easily generalizable to multivariate regression models, and OPDN, which uses an extremely efficient draw‐by‐draw random‐sampling‐without‐replacement algorithm, can use virtually any permutation statistic, so both have a very wide range of application. And the time complexity of both OPDY and OPDN is sublinear, making them not only the fastest but also the only truly scalable bootstrap and permutation test algorithms, respectively, in SAS. WIREs Comput Stat 2013. doi: 10.1002/wics.1266

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Bootstrap and Resampling

Statistical and Graphical Methods of Data Analysis > Nonparametric Methods

Software for Computational Statistics > Software/Statistical Software
Different Metal Aggregation in Copper Acetate Chain Coordination Polymers with Dipyridyl Tethers Bearing Hydrogen Bonding Capable Functional Groups
Authors: Uebler Jacob W. , Stone Brandon S. , LaDuca Robert L.
Published: June 2013

Hydrothermal synthesis has afforded a pair of divalent copper acetate coordination polymers containing either 4, 4′‐dipyridylamine (dpa) or 4‐pyridylisonicotinamide (4‐pina), both of which hydrogen‐bonding capable central functional groups. X‐ray crystallography revealed that both exhibit a 1D chain dimensionality. Use of the kinked tethering ligand dpa produced [Cu(OAc)2(dpa)]n (1), which possesses a simple chain based on dpa linkage of isolated copper ions. On the other hand, employing the straighter amide ligand 4‐pina generated {[Cu(OAc)2(4‐pina)]·0.5H2O}n (2), which exhibits {Cu2O2} rhomboid dimers formed through bridging acetate ligands. Weak antiferromagnetic coupling [g = 1.984(3), J = –3.2(3) cm–1] was observed within the axial‐equatorial bridged {Cu2O2} dimers in 2, with possible ferrimagnetism due to spin canting below 11 K.
Usefulness of biochemical parameters in decision‐making on the start of emergency treatment in patients with propionic acidemia
Authors: Zwickler Tamaris , Riderer Alina , Haege Gisela , Hoffmann Georg F. , Kölker Stefan , Burgard Peter
Published: June 2013

Background

Recurrent acute and life‐threatening metabolic decompensations are thought to be the major cause of mortality and morbidity in patients with propionic acidemia (PA). Since metabolic decompensations in these patients usually develop gradually, there is considerable uncertainty about the beginning and when emergency treatment should be initiated. The major aim of this study was to evaluate the usefulness of biochemical parameters for improving decision‐making on the start of emergency treatment.

Methods

We analysed data of 16 PA patients continuously followed in our centre. Metabolic decompensation was defined clinically by the occurrence of at least one of three alarming symptoms: vomiting, food refusal or impaired consciousness. Thirty‐eight biochemical parameters were analysed.

Results

A total of 259 metabolic decompensations were documented and compared with 625 routine visits. Among the symptoms used to clinically define metabolic decompensations, vomiting was most frequent (87 %). In total, 19 biochemical parameters differentiated between metabolic decompensations and routine visits. Among them ammonia, acid–base balance and anion gap were most reliable to identify a metabolic decompensation, and to estimate its severity. A comparative analysis of patients with PA and methylmalonic acidemia during metabolic decompensation showed similar results.

Conclusions

Ammonia, acid–base balance and anion gap are important biochemical parameters to identify an (impending) metabolic decompensation and to assess its severity in PA patients. The identified biochemical parameters should be integrated in an algorithm for clinical decision‐making on emergency treatment and should be tested in a prospective trial.
Combined effects of social pressure from the inside and outside of fishing communities promote cooperation for stock management
Authors: Furuzono Yuto , Yamakawa Takashi , Ohnishi Shuhei , Kaneko Takaomi
Published: June 2013

We analyze a coupled socioeconomic and bioeconomic dynamics model for fisheries management in a local community. In the model, fishermen choose to cooperate with the fisheries management rule or not at each time step, depending on the utilities of each option. The social dynamics is coupled with the dynamics of the stock biomass. Fishermen's utility basically depends on their catch, and the utility function of the noncooperative option is penalized by a psychological punishment, “social pressure”, which is affected by both the fraction of cooperative players and stock abundance. We classify social pressure into two categories: pressure originating from the inside and from the outside of the community. We develop a utility function with these social pressures and analyze the coupled dynamics. Our results show that all fishermen can end up cooperating with the management rule if both sources of internal and external social pressure have sufficient effect. The results imply that psychological aspects on fishermen can have an important role for successful management of local fisheries.
Impact of collisional versus viscous dissipation on flow instabilities in gas–solid systems
Authors: Yin Xiaolong , Zenk John R. , Mitrano Peter P. , Hrenya Christine M.
Published: June 2013

Flow instabilities encountered in the homogeneous cooling of a gas–solid system are considered via lattice-Boltzmann simulations. Unlike previous efforts, the relative contribution of the two mechanisms leading to instabilities is explored: viscous dissipation (fluid-phase effects) and collisional dissipation (particle-phase effects). The results indicate that the instabilities encountered in the gas–solid system mimic those previously observed in their granular (no fluid) counterparts, namely a velocity vortex instability that precedes in time a clustering instability. We further observe that the onset of the instabilities is quicker in more dissipative systems, regardless of the source of the dissipation. Somewhat surprisingly however, a cross-over of the kinetic energy levels is observed during the evolution of the instability. Specifically, the kinetic energy of the gas–solid system is seen to become greater than that of its granular counterpart (i.e. same restitution coefficient) after the vortex instability sets in. This cross-over of kinetic energy levels between a more dissipative system (gas–solid) and a less dissipative system (granular) can be explained by the alignment of particle motion found in a vortex. Such alignment leads to a reduction in both collisional and viscous energy dissipation due to the more glancing nature of collisions.
Comparison of milks processed by the direct and indirect methods of ultra-high-temperature sterilization: V. Denaturation of the whey proteins
Authors: Lyster R. L. J. , Wyeth T. C. , Perkin A. G. , Burton H.
Published: June 2013

The distribution of protein nitrogen was determined in milk treated by an experimental ultra-high-temperature (UHT) plant, operating alternatively as an indirect or as a direct heating plant.

The extent of denaturation of β-lactoglobulin can be used to assess the relative severity of UHT heat treatments; this criterion was used to compare the indirect and direct arrangements of the plant with each other and with other published results.

The time-temperature profiles of the plant were used to calculate the expected extent of denaturation of β-lactoglobulin during treatment of the milk. The results of the calculations are in fair agreement with the analytical results.
APeltulaNyl. diversity hotspot in north-east Portugal, with one species new to science and three species new to mainland Europe
Authors: MARQUES Joana , SCHULTZ Matthias , PAZ-BERMÚDEZ Graciela
Published: June 2013

Recent fieldwork carried out for the study of the lichen flora in the Upper Douro region (north-east Portugal) has resulted in a remarkable collection ofPeltulaspecimens, including one new species (Peltula lobataJ. Marques, M. Schultz & Paz-Berm.), three new species records for mainland Europe [Peltula bolanderi(Tuck.) Wetmore,Peltula farinosaBüdel andPeltula zahbruckneri(Hasse) Wetmore] and seven species new for mainland Portugal, that are reported here with a notes on their morphology and currently known distribution. The new speciesPeltula lobatais differentiated from any other knownPeltulaspecies by its thallus shape and size, presence of large, sessile apothecia with widely opened discs and by a complete absence of soredia. Identical specimens were also obtained from the nearby locality of Siega Verde in the province of Salamanca, and from the southern locality of Abla in the province of Almeria, both in Spain. New insights into the morphological diversity ofPeltula euplocaandPeltula bolanderiare also provided. The region is revealed to be a hotspot forPeltuladiversity and a very promising area for further research on the morphological and molecular variation among the former species. A revised key to European species of the genus is also presented.
An integrated theory of language production and comprehension
Authors: Pickering Martin J. , Garrod Simon
Published: June 2013

Currently, production and comprehension are regarded as quite distinct in accounts of language processing. In rejecting this dichotomy, we instead assert that producing and understanding are interwoven, and that this interweaving is what enables people to predict themselves and each other. We start by noting that production and comprehension are forms of action and action perception. We then consider the evidence for interweaving in action, action perception, and joint action, and explain such evidence in terms of prediction. Specifically, we assume that actors construct forward models of their actions before they execute those actions, and that perceivers of others' actions covertly imitate those actions, then construct forward models of those actions. We use these accounts of action, action perception, and joint action to develop accounts of production, comprehension, and interactive language. Importantly, they incorporate well-defined levels of linguistic representation (such as semantics, syntax, and phonology). We show (a) how speakers and comprehenders use covert imitation and forward modeling to make predictions at these levels of representation, (b) how they interweave production and comprehension processes, and (c) how they use these predictions to monitor the upcoming utterances. We show how these accounts explain a range of behavioral and neuroscientific data on language processing and discuss some of the implications of our proposal.
It ain't what you do (it's the way that you do it)
Authors: Aitken Kenneth John
Published: June 2013

Knowledge of the complexity of human communication comes from three main sources – (i) studies of the linguistics and neuropsychology of dysfunction after brain injury; (ii) studies of the development of social communication in infancy, and its dysfunction in developmental psychopathologies; and (iii) the evolutionary history of human communicative interaction. Together, these suggest the need for a broad, integrated theory of communication of which language forms a small but critical component.
Evidence for, and predictions from, forward modeling in language production
Authors: Alario F.-Xavier , Hamamé Carlos M.
Published: June 2013

Pickering & Garrod (P&G) put forward the interesting idea that language production relies on forward modeling operating at multiple processing levels. The evidence currently available to substantiate this idea mostly concerns sensorimotor processes and not more abstract linguistic levels (e.g., syntax, semantics, phonology). The predictions that follow from the claim seem too general, in their current form, to guide specific empirical tests.
Forward modelling requires intention recognition and non-impoverished predictions
Authors: de Ruiter Jan P. , Cummins Chris
Published: June 2013

We encourage Pickering & Garrod (P&G) to implement this promising theory in a computational model. The proposed theory crucially relies on having an efficient and reliable mechanism for early intention recognition. Furthermore, the generation of impoverished predictions is incompatible with a number of key phenomena that motivated P&G's theory. Explaining these phenomena requires fully specified perceptual predictions in both comprehension and production.
What is the context of prediction?
Authors: Yoon Si On , Brown-Schmidt Sarah
Published: June 2013

We agree with Pickering & Garrod's (P&G's) claim that theories of language processing must address the interconnection of language production and comprehension. However, we have two concerns: First, the central notion of context when predicting what another person will say is underspecified. Second, it is not clear that P&G's dual-mechanism model captures the data better than a single-mechanism model would.
Inner speech as a forward model?
Authors: Oppenheim Gary M.
Published: June 2013

Pickering & Garrod (P&G) consider the possibility that inner speech might be a product of forward production models. Here I consider the idea of inner speech as a forward model in light of empirical work from the past few decades, concluding that, while forward models could contribute to it, inner speech nonetheless requires activity from the implementers.
Higher-order psi-calculi
Authors: PARROW JOACHIM , BORGSTRÖM JOHANNES , RAABJERG PALLE , ÅMAN POHJOLA JOHANNES
Published: June 2013

In earlier work we explored the expressiveness and algebraic theory Psi-calculi, which form a parametric framework for extensions of the pi-calculus. In the current paper we consider higher-order psi-calculi through a technically surprisingly simple extension of the framework, and show how an arbitrary psi-calculus can be lifted to its higher-order counterpart in a canonical way. We illustrate this with examples and establish an algebraic theory of higher-order psi-calculi. The formal results are obtained by extending our proof repositories in Isabelle/Nominal.
Public services in Erfurt and Frankfurt am Main compared (c. 1890–1914): capabilities in Prussia?
Authors: SCHMIDT JÜRGEN
Published: June 2013

How can a modern concept like Amartya Sen's capability approach be introduced in historical studies? One possibility is to ask how public services were implemented in municipal policy and how these services open up capabilities for the individuals of a city. This article uses Sen's theoretical framework as an analytical tool to explore two Prussian towns, Erfurt and Frankfurt am Main, and their public services (job centres and tramway systems) as examples of social policy at the local level.
Looking for adolescents' well-being: self-efficacy beliefs as determinants of positive thinking and happiness
Authors: Caprara Gian Vittorio , Steca Patrizia , Gerbino Maria , Paciello Marinella , Vecchio Giovanni Maria
Published: June 2013

Aims– The present study is part of a longitudinal project aimed at identifying the personal characteristics and the developmental pathways conducive to successful adaptation from childhood to adulthood. The study examined the concurrent and longitudinal impact of self-efficacy beliefs on subjective well-being in adolescence, namely positive thinking and happiness. Positive thinking has been operationalized as the latent dimension underlying life satisfaction, self-esteem and optimism. Happiness has been operationalized as the difference between positive and negative affects, as they are experienced in a variety of daily situations.Methods– In a group of 664 Italian adolescents, a structural model positing adolescents' emotional and interpersonal self-efficacy beliefs as proximal and distal determinants of positive thinking and happiness has been tested.Results– Findings attest to the impact of affective and interpersonal-social self-efficacy beliefs on positive thinking and happiness both concurrently and longitudinally.Conclusions– Adolescents' self-efficacy beliefs to manage positive and negative emotions and interpersonal relationships contribute to promote positive expectations about the future, to mantain a high self-concept, to perceive a sense of satisfaction for the life and to experience more positive emotions.

Declaration of Interest: none.
Categorization and legality of autonomous and remote weapons systems
Authors: Liu Hin-Yan
Published: June 2013

This article reconsiders the status and legality of both autonomous and remote weapons systems under international humanitarian law. Technologically advanced unmanned military systems are being introduced into the modern battlespace with insufficient recognition of their potential challenge to international humanitarian law. The article questions the understanding of both autonomous and remote weapons systems as ‘weapons’ and seeks to consider how their use may impact existing legal categories. Their use is then specifically situated to consider the legality of their deployment in certain contexts. Finally, the article raises the question of impunity for the use of both autonomous and remote weapons systems that arise from the inability to attribute responsibility for the harm they cause. It is imperative that law and policy are developed to govern the development and deployment of these advanced weapons systems to forestall these likely situations of impunity.
Beyond the Call of Duty: why shouldn't video game players face the same dilemmas as real soldiers?
Authors: Clarke Ben , Rouffaer Christian , Sénéchaud François
Published: June 2013

Video games are influencing users' perceptions about what soldiers are permitted to do during war. They may also be influencing the way combatants actually behave during today's armed conflicts. While highly entertaining escapism for millions of players, some video games create the impression that prohibited acts, such as torture and extrajudicial killing are standard behaviour. The authors argue that further integration of international humanitarian law (IHL) can improve knowledge of the rules of war among millions of players, including aspiring recruits and deployed soldiers. This, in turn, offers the promise of greater respect for IHL on tomorrow's battlefields.
Cost and losses associated with offshore wind farm collection networks which centralise the turbine power electronic converters
Authors: Parker Max Alexander , Anaya‐Lara Olimpo
Published: June 2013

Costs and losses have been calculated for several different network topologies, which centralise the turbine power electronic converters, in order to improve access for maintenance. These are divided into star topologies, where each turbine is connected individually to its own converter on a platform housing many converters, and cluster topologies, where multiple turbines are connected through a single large converter. Both AC and DC topologies were considered, along with standard string topologies for comparison. Star and cluster topologies were both found to have higher costs and losses than the string topology. In the case of the star topology, this is due to the longer cable length and higher component count. In the case of the cluster topology, this is due to the reduced energy capture from controlling turbine speeds in clusters rather than individually. DC topologies were generally found to have a lower cost and loss than AC, but the fact that the converters are not commercially available makes this advantage less certain.
Three‐dimensional bearing load share behaviour in the planetary stage of a wind turbine gearbox
Authors: LaCava William , Xing Yihan , Marks Chris , Guo Yi , Moan Torgeir
Published: June 2013

The Gearbox Reliability Collaborative has conducted extensive field and dynamometer test campaigns on two heavily instrumented wind turbine gearboxes. In this study, the load sharing behaviour between six bearings in the planetary stage is described using a combined approach of measurement and simulation. First, planet‐bearing data are analysed to characterise planetary stage behaviour in different environments. Second, a method is described for integrating the measured responses of the planetary stage into an advanced model of the bearing life that significantly changes the life prediction. Third, a sensitivity study of the planet bearings is conducted using multibody gearbox models. Various levels of gearbox flexibility and different planet assembly fits are investigated and compared with experimental observations. Measurements in the dynamometer and field show that bearing loading differs significantly between the six planet bearings. The relative loading behaviour of the planetary stage bearings is directly influenced by boundary conditions of the planet carrier pins. Assembly differences between two identically designed gearboxes cause different load sharing behaviour. Simulations are used to quantify the effect of different component flexibilities. Reduced order models are developed to accurately predict bearing loading in a cost‐efficient manner.
Evaluation of the Biodegradable Plates (PG910/PDO) for Reconstruction of Various Sizes of Orbital Floor Defects in the Blow-Out Fractures
Authors: Tabrizi Reza , Langner Nicole J. , Pouzesh Ayatollah , Arabion Hamidreza
Published: June 2013

The aim of our study was to evaluate the biodegradable plates (PG910/PDO) for reconstruction of various sizes of the orbital floor defects in the blow-out fractures. We included patients who had an impure blow-out fracture. All patients had a recent trauma and also the surgical intervention was done between 1 and 10 days after trauma. The amount of the orbital floor defect was measured in each case through computed tomography scan. In the surgical intervention, a biodegradable plate was used for the reconstruction of the orbital floor defect along with titanium miniplates used for bone fixation in orbital rim. Due to aesthetic reasons, all patients underwent secondary surgery including removal of titanium miniplates after 18 months. The orbital floor was reevaluated during the removal of the miniplates. The clinical evaluation of remnant defects and biodegradable plates (presence of complete or partial resorption) were documented for each patient. In our study a total of 15 patients (10 males and 5 females) underwent the orbital floor reconstruction using biodegradable miniplates. The size of the orbital floor defects was meanly 3.51 ± 1.29 cm2. Results demonstrated that 4 out of 15 patients had a remnant defect after resorption of the biodegradable plate. In 10 out of 15 patients, the biodegradable plates completely replaced with fibrous tissues after 18 months. Remaining five patients had partial resorption of plates. There was not any relationship between the defect size and the remnant defects ( p > 0.05). A significant relationship was seen between the defect size and the plates’ resorption rate ( p < 0.001). There is a significant relationship between the resorption rate and the remnant defect. The risk to have remnant defects have been increased as the plates had incomplete resorption. The use of biodegradable plates is an appropriate option for reconstruction of the orbital floor defects. The defect size does not have any effect on the stability of the plate. However, incomplete plate resorption increases the risk of remnant defects in the orbital floor. The larger defects lead to slow degradation of biodegradable plates.
Anomalous intrinsic viscosity of octadecylamine-functionalised carbon nanotubes in suspension
Authors: Donovan K. J. , Scott K.
Published: June 2013

Single walled carbon nanotubes, SWCNTs, are used as a model cylinder of nanoscopic dimensions for testing rheological theories of how addition of cylindrical particles affects the viscosity of a suspension of such particles. Using the rate of growth of the accompanying induced linear dichroism following application of an applied electric field, the dynamics of carbon nanotube alignment is studied in suspensions of octadecylamine functionalised single walled carbon nanotubes, ODA-SWCNTs, in 1,2 dichloroethane. From such measurements the viscosity of the suspension is measured as the concentration of the suspension is varied. While working within the dilute limit the viscosity is found to increase linearly with concentration and the intrinsic viscosity of the suspension is found to be 8000. This anomalously high intrinsic viscosity is compared with the predictions of various models for a rigid cylinder and found to be incompatible with any of the current models. Some suggestions are made as to the way this ODA-SWCNT result may be eventually accommodated within other models.
Higher order and asymmetry effects on saturation of magnetic islands
Authors: Smolyakov A. I. , Poye A. , Agullo O. , Benkadda S. , Garbet X.
Published: June 2013

Higher order asymptotic matching procedure is developed to derive the nonlinear equation for saturated magnetic island with the symmetric profile of the equilibrium current. The theory extends the previous results to include higher order effects such as nonlinear modification of the equilibrium current and asymmetry in the boundary conditions in the outer region. It is shown that due to a finite width of the nonlinear region, the magnitude of the magnetic flux at the rational surface is different from the asymptotic value found from the outer solution, resulting in the suppression of the island growth for higher values of Δ′ parameter.
The influence of the secondary relaxation processes on the structural relaxation in glass-forming materials
Authors: Khamzin A. A. , Popov I. I. , Nigmatullin R. R.
Published: June 2013

In the frame of fractional-kinetic approach, the model of the structural α-relaxation in the presence of the secondary β-relaxation processes is suggested. The model is based on the rigorous bond between β-processes with α-process and leads to the generalized and justified expression for the complex dielectric permittivity (CDP). It allows to form a new sight on the problem of the fitting of multi-peak structure of the dielectric loss spectra in glass-forming materials. The consistency of the CDP expressions obtained is based on a good fit of experimental data for binary methanol-water mixtures.
A high speed three-dimensional spectral domain optical coherence tomography with <2 μm axial resolution using wide bandwidth femtosecond mode-locked laser
Authors: Kuroda Hiroto , Baba Motoyoshi , Suzuki Masayuki , Yoneya Shin
Published: June 2013

We have developed an ultra-high-resolution optical coherence tomography (OCT) equipment, using a 200 nm bandwidth spectrometer and a mode-locked femtosecond laser. We have characterized this OCT, obtaining high spatial resolution in the axial direction of less than 2 μm in air via single scanning, within only 20 ms. This corresponds to an ultra-high resolution of less than 1.3 μm for measurements at the fundus retina. High resolution and high speed imaging enables us to selectively obtain a clear three dimensional (3D) lamina cribrosa itself from a 3D optic disc (OD) image in vivo.
Atypical phonon modes in zinc-blende BN/GaN superlattices
Authors: Talwar Devki N.
Published: June 2013

Comprehensive results of the atomic vibrations are reported in unconventional short-period zb BN/GaN superlattices (SLs) by exploiting a rigid-ion-model and taking into account both the short-range and long-range Coulomb interactions. Besides the anisotropic mode behavior of optical phonons, our study provided evidence of acoustic-mode anti-crossing, mini-gap formation, confinement, as well as BN-like modes falling within the gap that separates optical phonon bands of the two materials. Controlling the vibrational spectrum by altering SL-period can create excellent opportunities for improving the electrical and thermal properties of SL-based III-N devices.
Evidence of rapid population decline of the eastern quoll (Dasyurus viverrinus) in Tasmania
Authors: Fancourt Bronwyn A. , Hawkins Clare E. , Nicol Stewart C.
Published: June 2013

Australia’s mammalian fauna has suffered unparalleled extinctions and declines in recent history. Tasmania has remained largely unaffected by these losses; however, marsupial dynamics are changing rapidly and new threats are emerging. Once abundant throughout south-eastern Australia, the eastern quoll (Dasyurus viverrinus) survives only in Tasmania. Until recently, it was considered widespread and common, but it may be undergoing a rapid and severe decline. The aim of this study was to quantify changes in eastern quoll populations over recent years. Data were compiled from statewide spotlight surveys, repeated historic trapping surveys and bycatch records from non-target trapping surveys. Spotlight surveys from 150 sites across Tasmania revealed a 52% reduction in the number of eastern quoll sightings over the 10 years to 2009. Declines of 61–100% were observed in trapping surveys at three study sites compared with trapping conducted 18–31 years earlier. A reduction in trap success was recorded in five of six non-target surveys, with declines of 51–100% over 1–12 years. These results suggest that the eastern quoll can no longer be presumed secure in Tasmania. Urgent management action may be needed to ensure the future conservation of the species in its last remaining stronghold.
Complete integrin headpiece opening in eight steps
Authors: Zhu Jieqing , Zhu Jianghai , Springer Timothy A.
Published: June 2013

Carefully soaking crystals with Arg-Gly-Asp (RGD) peptides, we captured eight distinct RGD-bound conformations of the αIIbβ3 integrin headpiece. Starting from the closed βI domain conformation, we saw six intermediate βI conformations and finally the fully open βI with the hybrid domain swung out in the crystal lattice. The β1-α1 backbone that hydrogen bonds to the Asp side chain of RGD was the first element to move followed by adjacent to metal ion-dependent adhesion site Ca2+, α1 helix, α1’ helix, β6-α7 loop, α7 helix, and hybrid domain. We define in atomic detail how conformational change was transmitted over long distances in integrins, 40 Å from the ligand binding site to the opposite end of the βI domain and 80 Å to the far end of the hybrid domain. During these movements, RGD slid in its binding groove toward αIIb, and its Arg side chain became ordered. RGD concentration requirements in soaking suggested a >200-fold higher affinity after opening. The thermodynamic cycle shows how higher affinity pays the energetic cost of opening.
Testing the limits of cell migration
Authors: Short Ben
Published: June 2013

Migrating cells are restricted by their ability to squeeze their nuclei through pores in the extracellular matrix.
The D50N mutation and syndromic deafness: Altered Cx26 hemichannel properties caused by effects on the pore and intersubunit interactions
Authors: Sanchez Helmuth A. , Villone Krista , Srinivas Miduturu , Verselis Vytas K.
Published: June 2013

Mutations in the GJB2 gene, which encodes Cx26, are the most common cause of sensorineural deafness. In syndromic cases, such as keratitis-ichthyosis-deafness (KID) syndrome, in which deafness is accompanied by corneal inflammation and hyperkeratotic skin, aberrant hemichannel function has emerged as the leading contributing factor. We found that D50N, the most frequent mutation associated with KID syndrome, produces multiple aberrant hemichannel properties, including loss of inhibition by extracellular Ca2+, decreased unitary conductance, increased open hemichannel current rectification and voltage-shifted activation. We demonstrate that D50 is a pore-lining residue and that negative charge at this position strongly influences open hemichannel properties. Examination of two putative intersubunit interactions involving D50 suggested by the Cx26 crystal structure, K61–D50 and Q48–D50, showed no evidence of a K61–D50 interaction in hemichannels. However, our data suggest that Q48 and D50 interact and disruption of this interaction shifts hemichannel activation positive along the voltage axis. Additional shifts in activation by extracellular Ca2+ remained in the absence of a D50–Q48 interaction but required an Asp or Glu at position 50, suggesting a separate electrostatic mechanism that critically involves this position. In gap junction (GJ) channels, D50 substitutions produced loss of function, whereas K61 substitutions functioned as GJ channels but not as hemichannels. These data demonstrate that D50 exerts effects on Cx26 hemichannel and GJ channel function as a result of its dual role as a pore residue and a component of an intersubunit complex in the extracellular region of the hemichannel. Differences in the effects of substitutions in GJ channels and hemichannels suggest that perturbations in structure occur upon hemichannel docking that significantly impact function. Collectively, these data provide insight into Cx26 structure–function and the underlying bases for the phenotypes associated with KID syndrome patients carrying the D50N mutation.
Do plant traits explain tree seedling survival in bogs?
Authors: Limpens Juul , van Egmond Emily , Li Bingxi , Holmgren Milena
Published: June 2013

Moss‐dominated peat bogs store approximately 30% of global soil carbon. A climate induced‐shift from current moss‐dominated conditions to tree‐dominated states is expected to strongly affect their functioning and carbon sequestration capacity. Consequently, unravelling the mechanisms that may explain successful tree seedling establishment in these ecosystems is highly relevant.

To assess the role of drought on early tree seedling establishment and the relative importance of plant traits in tree seedling survival, we conducted a factorial glasshouse experiment with seven conifer species.

Our results show that drought inhibits moss growth, thereby increasing survival of tree seedlings. Survival success was higher in Pinus than in Picea species, ranking Pinus banksiana > Pinus sylvestris > Pinus nigra > Picea mariana > Picea glauca, Picea sitchensis > Picea rubens. We found that those species most successful under dry and wet conditions combined a fast shoot growth with high seed mass.

We conclude that plant traits contribute to explaining successful early tree seedling establishment in bogs.