bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of a tri-carbon defect and its relation to the ultraviolet absorption in aluminum nitride
Authors: Irmscher K. , Hartmann C. , Guguschev C. , Pietsch M. , Wollweber J. , Bickermann M.
Published: September 2013

We report on the identification of a tri-carbon defect in AlN bulk crystals grown by physical vapor transport. The defect gives rise to a single infrared absorption line at 1769 cm−1 in unintentionally carbon doped crystals. This line splits into eight lines in crystals enriched with the carbon isotope 13C. The observed line patterns can unambiguously be assigned to a local vibrational mode of a defect that contains exactly three carbon atoms. The most probable arrangement of the three carbon atoms is on nearest-neighbor substitutional sites, replacing two nitrogen atoms and one aluminum atom, whereby one carbon-carbon bond is directed non-parallel and the other parallel to the crystal's c axis. It is suggested that the tri-carbon defect can exist in three different charge states (neutral, singly negative, and doubly negative) and hence possesses two transition levels within the band gap. This energy level scheme explains the appearance and disappearance of the local vibrational mode in dependence on the Fermi level position as well as a similar appearance-disappearance behavior of a strong ultraviolet absorption band at 4.7 eV that has been repeatedly reported in the literature. We propose that the singly negative charge state of the tri-carbon defect essentially contributes to that ultraviolet absorption.
An accelerated exposure and testing apparatus for building joint sealants
Authors: White C. C. , Hunston D. L. , Tan K. T. , Hettenhouser J. , Garver J. D.
Published: September 2013

The design, fabrication, and implementation of a computer-controlled exposure and testing apparatus for building joint sealants are described in this paper. This apparatus is unique in its ability to independently control and monitor temperature, relative humidity, ultraviolet (UV) radiation, and mechanical deformation. Each of these environmental factors can be controlled precisely over a wide range of conditions during periods of a month or more. Moreover, as controlled mechanical deformations can be generated, in situ mechanical characterization tests can be performed without removing specimens from the chamber. Temperature and humidity were controlled during our experiments via a precision temperature regulator and proportional mixing of dry and moisture-saturated air; while highly uniform UV radiation was attained by attaching the chamber to an integrating sphere-based radiation source. A computer-controlled stepper motor and a transmission system were used to provide precise movement control. The reliability and effectiveness of the apparatus were demonstrated on a model sealant material. The results clearly show that this apparatus provides an excellent platform to study the long-term durability of building joint sealants.
Magnetic field induced phase transformation in polycrystalline NiCoMnAl thin films
Authors: Rios S. , Bufford D. , Karaman I. , Wang H. , Zhang X.
Published: September 2013

NiCoMnAl thin films were deposited onto unheated substrates using dc magnetron co-sputtering. The microstructure of as-deposited films consisted of nanocrystals in an amorphous matrix and did not exhibit a martensitic phase transformation. After heat treatment, films crystallized into a B2 austenite phase, which exhibited a magnetic field induced martensitic phase transformation. The level of the change in the martensitic transformation temperatures in the magnetic field was determined to be ∼2.1 K/T. The films exhibited non-reversible magnetic field induced martensite to austenite transformation due to the large thermal hysteresis.
Diluted magnetism in Mn-doped SrZnO2 single crystals
Authors: Rahman M. R. , Koteswararao B. , Huang S. H. , Hoon Kim Kee , Chou F. C.
Published: September 2013

We have investigated the magnetic properties of Mn- and Cu-substituted SrZnO2 single crystals (SrZn1−xMnxO2 and SrZn1−xCuxO2). We observed signatures of weak ferromagnetism as a sharp increase of magnetic susceptibility below 5 K even in the low-percentage (x = 0.01) of Mn-substituted single crystals. Magnetic susceptibility data measured parallel or perpendicular to the ab-plane yield anisotropic behavior with Curie–Weiss temperature of about −320 K and −410 K, respectively, suggesting the presence of strong antiferromagnetic couplings among Mn at high temperatures, similar to the Mn-doped ZnO and Fe-doped BaTiO3. In contrast, the SrZn0.99Cu0.01O2 crystal shows paramagnetic behavior down to 2 K.
Mechanically durable superhydrophobic surfaces prepared by abrading
Authors: Wang Fajun , Yu Shan , Ou Junfei , Xue Mingshan , Li Wen
Published: September 2013

Superhydrophobic surfaces with both excellent mechanical durability and easy reparability based on polytetrafluoroethylene/room temperature vulcanized silicone rubber (PTFE/RTVSR) composites were prepared by a simple abrading method. The surface energy of RTVSR matrix decreased with the increasing volume fraction of PTFE particles, and the surface rough microstructures of the composites were created by abrading. A water droplet on the surface exhibited a contact angle of about 165° ± 3.4° and a sliding angle of about 7.3° ± 1.9°. Such superhydrophobic surfaces showed strong mechanical durability against sandpaper because the surfaces were prepared in the way of mechanical abrasion, and the fresh exposed surfaces were still superhydrophobic. In addition, the micro-structures on the elastic surface of the composite will be compressed by elastic deformation to avoid being broken during the friction cycles when cotton fabric was used as an abrasion surface. The deformation will rebound to renew the original surface structures when the load is withdrawn. Therefore, the elastic PTFE/RTVSR composites are of advantage to construct superhydrophobic surfaces with better abrasion resistance. More importantly, such superhydrophobicity can be repaired by a simple abrading regeneration process within a few minutes when the surface is damaged or polluted by organic contaminant.
Depth profiling of nitrogen within 15N-incorporated nano-crystalline diamond thin films
Authors: Garratt E. , AlFaify S. , Cassidy D. P. , Dissanayake A. , Mancini D. C. , Ghantasala M. K. , Kayani A.
Published: September 2013

Nano-Crystalline Diamond (NCD) thin films are a topic of recent interest due to their excellent mechanical and electrical properties. The inclusion of nitrogen is a specific interest as its presence within NCD modifies its conductive properties. The methodology adopted for the characterization of nitrogen incorporated NCD films grown on a chromium underlayer determined a correlation between the chromium and nitrogen concentrations as well as a variation in the concentration profile of elements. Additionally, the concentration of nitrogen was found to be more than three times greater for these films versus those grown on a silicon substrate.
The effects of La substitution on ferroelectric domain structure and multiferroic properties of epitaxially grown BiFeO3 thin films
Authors: Kim Woo-Hee , Yeog Son Jong
Published: September 2013

We report the influence of La substitution in epitaxial BiFeO3 thin films prepared by pulsed layer deposition on a Nb-doped SrTiO3 substrate, focusing on ferroelectric domain structure, leakage current, and multiferroic properties. Enhanced ferroelectric remanent polarization and reduced leakage current density were established via La substitution in the BiFeO3 film. Based on leakage conduction mechanism and piezoelectric force microscopy studies, this is indicative of reduced trap densities and increased domain energy. Besides that, the ferromagnetic properties were improved by the La doping as well. The possible mechanisms for the enhancement of electrical and multiferroic characteristics are extensively discussed.
AlxGa1−xAs minority carrier lifetime enhancement at low temperatures
Authors: Heckelmann Stefan , Lackner David , Dimroth Frank , Bett Andreas W.
Published: September 2013

DX-centers in AlxGa1−xAs are known to reduce the minority carrier lifetime. Thus, DX-centers influence various semiconductor device characteristics. However, at temperatures below 100 K, we observed an unexpected improvement in the short circuit current density of an investigated Al0.37Ga0.63As solar cell. Using temperature-dependent capacitance measurements taken on a similar Al0.37Ga0.63As n−p+-diode, we correlated this behavior with the persistent photoconductivity effect. This effect derives from the suppressed silicon-DX-center generation inside the n-doped material at low temperatures.
The Ethics of Tourist Photography: Tourists' Experiences of Photographing Locals in Peru
Authors: Scarles Caroline
Published: September 2013

Despite references to photography as a tool for consuming and constructing the tourist experience, little attention has been afforded to the effects of such practice. In this paper I therefore seek to unpack the ethics of the seemingly fleeting relationships between tourists and host communities that emerge during photographic encounters. Focusing on the emergent interactions between tourists and locals who are photographed, I explore the social and cultural values that underpin tourists' ethical considerations of whether or not to photograph local people. In doing so, I first contend that tourists draw upon a range of photographic strategies as they negotiate the moral maze of ethical considerations during photographic encounters and engagement with locals at destinations. Secondly, I suggest that the ethical considerations of tourist photographic practice find genesis in a web of partial knowledges, subjective interpretations, and reflexive performances of self and others. In doing so, I propose that tourist practice is driven by subjective interpretations of that which is appropriate, acceptable, or responsible with regard to photographing. Thus, I contend, an immanence of ethical consideration arises in the immediacy of the moment of photographing, as photography emerges as a complex fusion of both predictable and reactionary practices that align general ethical viewpoints with unpredictable ethical responses.
Pax7 is critical for the normal function of satellite cells in adult skeletal muscle
Authors: von Maltzahn Julia , Jones Andrew E. , Parks Robin J. , Rudnicki Michael A.
Published: September 2013

Significance

Skeletal muscle exhibits a remarkable ability to regenerate, a process that has been demonstrated to be dependent on satellite cells. Satellite cells uniformly express the transcription factor paired box 7 (Pax7), and extensive analysis of
Pax7
-deficient mice has documented the progressive loss of the satellite cell lineage likely due to a failure to proliferate together with precocious differentiation. In contrast to these findings, a recent provocative study suggested that Pax7 was entirely dispensable in adult life. Here, we demonstrate that Pax7 expression is an absolute prerequisite for the normal function of satellite cells during regenerative myogenesis at any age. Our experiments therefore demonstrate that Pax7 plays an essential role in regulating the myogenic potential and function of satellite cells.
The “BIG BIRD” of the “YELLOW YOUNG” Man: Do Nontarget Properties Cascade?
Authors: Roux Sébastien , Bonin Patrick , Kandel Sonia
Published: September 2013

This study investigated whether in speech production object properties flow in a cascaded manner or whether cascaded processing is restricted to the object's identity. In Experiments 1 and 2, participants saw pictured objects and had to state either their size (GRAND or PETIT—meaning big and small) or their name. The size of the objects varied as a function of the way they were presented on the computer screen (Experiment 1) or their real size in the world (Experiment 2). In Experiment 3, faces of young and old men were coloured in yellow or in green. The task was to name either the colour (JAUNE or VERT, meaning yellow and green, respectively) or the age (JEUNE or VIEUX, meaning young and old, respectively) of the face. In Experiments 1 and 2, no reliable effects of phonological relatedness (“GORILLE– g rand”—a big gorilla) were found on the object-naming latencies. However, size-naming latencies were shorter when the adjective shared the initial phoneme of the picture name (i.e., “GRAND– gorille”) than when it did not (i.e., “GRAND–dinosaure”—saying “ big” in response to a big dinosaur). In Experiment 3, phonological overlap did not affect colour naming latencies, or age naming latencies. Overall, these findings strongly suggest that cascaded processing is restricted to the object's identity in conceptually driven naming tasks.
Estimated Burden of Methicillin-Resistant Staphylococcus aureus in California Hospitals after Changes to Administrative Codes, 2005–2010
Authors: Tehrani David M. , Cao Chenghua , Kwark Homin , Huang Susan S.
Published: September 2013

We assess the impact of revised International Classification of Diseases, Ninth Revision, codes on methicillin-resistant Staphylococcus aureus burden in California hospitals. Codes were rapidly adopted, demonstrating new capture of colonization and continued relatively stable capture of infections. Nevertheless, despite new colonization codes, coded data demonstrated poor retention between serial hospitalizations.
6. The clash of the Titans: the macro-ideologies
Authors: Freeden Michael
Published: September 2013

‘The clash of the Titans: the macro-ideologies’ moves on from analysing ideologies to survey the forms that political ideologies have adopted. The prevailing ideologies in the 20th-century have sought to offer solutions to all the important political issues confronting society. These macro-ideologies have sought social and political dominance on both national and international levels. Liberalism, conservatism, socialism, fascism, communism, and other ideologies have shaped the political experience of the modern world and each is considered in turn. In totalitarian ideologies, these struggles for dominance have resulted in epic, and often bloody, confrontations.
7. Segments and modules: the micro-ideologies
Authors: Freeden Michael
Published: September 2013

The age of the mainstream ideologies is not over. But in ‘Segments and modules: the micro-ideologies’ the constant mutation of ideologies and the emergence of fragmented ideologies are traced. Libertarianism, neo-Liberalism, nationalism, feminism, and religious fundamentalism, are all explored as manifestations of the constant tidal pull between the decentralization of political power and its recentralization. The evidence makes it clear that ideologies cannot come to an end, and there isn't a winning ideology as announced by the ‘end of history’ prophets in the 1990s. History is not yet at the finishing post.
4. Realism and anti‐realism
Authors: Okasha Samir
Published: September 2013

‘Realism and anti-realism’ is concerned with the debate between scientific realism and its converse, anti-realism or instrumentalism. Realists hold that the aim of science is to provide a true description of the world. Anti-realists hold that it is to provide a true description of the ‘observable’ part of the world. The ‘no miracles’ argument, one of the strongest arguments for scientific realism, is shown to be a plausibility argument — an inference to the best explanation. Central to the debate between realism and anti-realism is the observable/unobservable distinction and the views of realist Grover Maxwell and anti-realist Bas van Fraassen are described. The underdetermination argument is also explained.
7. Science and its critics
Authors: Okasha Samir
Published: September 2013

Is science a good thing? ‘Science and its critics’ considers three criticisms of science that are of particular philosophical interest. The first is concerned with Scientism, a pejorative label used by some philosophers to describe what they see as science-worship — the over-reverential attitude towards science found in many intellectual circles. The second discusses the tension between science and religion and outlines the theory of creationism, which insists that the biblical account of creation is literally true, and that Darwin's theory of evolution is therefore completely wrong. Finally, the arguments for and against the possibility of value-free science are discussed.
2. A brief history of American political parties
Authors: Maisel L. Sandy
Published: September 2013

‘A brief history of American political parties’ traces the development of the modern political parties in the US from the initial emergence of parties as the Founders differed on policies they believed served the nation's best interests. The modern day Democratic Party has been transformed from its early manifestation as the Democratic-Republican Party, whilst the Republican Party was formed as a result of the division over the issue of slavery and eclipsed earlier parties such as the National Republicans and Whigs as the major alternative to the Democrats. The subsequent widening of the franchise impacted on the character of both parties.
6. Subnational nominations and elections
Authors: Maisel L. Sandy
Published: September 2013

‘Subnational nominations and elections’ examines how candidates are selected to run for office below the level of the presidency, and then in general election campaigns. The importance of single-member districts, the ways in which electoral districts are drawn and the financing of elections and the ways that campaigns are contested are each explored, though it is concluded that the overwhelmingly important factors in these elections are whether the President and Party in power are popular and the electorate satisfied with their performance. If they are the status quo will be maintained.
7. Far from the perfect democracy
Authors: Maisel L. Sandy
Published: September 2013

Americans, even those familiar with the details of the electoral process, remain convinced that American democracy represents the ideal towards which others should strive. ‘Far from the perfect democracy’ examines some of the flaws in the system which sees such low levels of participation, the unsatisfactory nomination process and election campaigns, as well as the huge costs and lack of competition in the process. Whilst these flaws have been pointed out by many reformers, solutions are not necessarily easy to come by without creating new problems, and few politicians relish the challenge of putting aside their own political interests to address these issues.
3. Electing Presidents (and Other Ways to Occupy the Oval Office)
Authors: Jones Charles O.
Published: September 2013

The design of the executive leadership helped shape the opportunities and establish the boundaries of presidential power. Would it work? ‘Electing Presidents’ looks at how the system of electing presidents developed and adapted and shows that constitutional construction and history were on the side of maintaining the unique method designed by the Founders. There were many initial questions to be ironed out: who would be the candidates? Would there be political parties? What would be the relationship between presidental and vice-presidental selection? Political parties function first and foremost to organize elections. The strength of parties is measured by their capacity to adapt to regional differences, regulations, and voter policy preferences.
7. Reform, Change, and Prospects for the Future
Authors: Jones Charles O.
Published: September 2013

The presidency is a frequent object of reformers. It is regarded by many to be the most powerful branch in the separated system. Of the three branches, Congress is most prone to propose reforms as it competes with the presidency for a share of power. ‘Reform, Change, and Prospects for the Future’ asks what the difference between reform and change is and relates the two in terms of the American presidency throughout history. What reforms to the American presidency have been successful? What are the lessons and effects of statutory reform? The future of the presidency is heavily influenced by its past and present. The best way to look to the future is through the prism of current politics. Effective presidential power in a separated system is that exercised in recognition of the legitimate functions of the other branches.
A brief history of the global warming debate
Authors: Maslin Mark
Published: September 2013

‘A brief history of the global warming debate’ describes the combination of factors that led to recognition and acceptance of global warming, beginning with global warming science carried out in the 1950s. The next stages came later in the 1980s: the observed upturn in the global temperature data set; the increased knowledge of past climate change; significant advances in global climate modelling; the emergence of the environmental movement; increased media interest; and finally politicians and economists taking the climate change threat seriously since the late 1990s. The signature of the United Nations Framework Convention on Climate Change at the Rio Earth Summit in 1992 and the subsequent ratification of the Kyoto Protocol in 2005 are also discussed.
Visions of a zero-carbon future
Authors: Maslin Mark
Published: September 2013

‘Visions of a zero-carbon future’ provides suggestions of what the low-carbon world of tomorrow might look like. Future homes and offices may all utilise water- and energy-efficient measures such as smart meters, solar panels, wind turbines, and rainwater harvesting. Our cities of the future could include more mixed-use developments featuring high-quality urban design and sustainable urban drainage systems. Transport could be transformed by greater use of public transport running on renewable energy sources. Continental air travel could be replaced with magnetically levitating trains travelling at 900km/h using renewable sources of electricity. The economy may be transformed by technological solutions to both emission reductions and adaptation to climate change, producing a global developed society unrecognisable from the present.
Final thoughts
Authors: Davies Owen
Published: September 2013

Magic does not live in the past — magic is alive and well today, all over the world. Magic has a range of meanings and has still has relevance. Magic is a language, a belief, an action, creative expression, experience, and a cognitive tool. Magic can be part of religion, but can also be independent of it. Science can explain magic but it cannot explain it away. Magic is part of the human condition and will always be with us.
CPPpred: prediction of cell penetrating peptides
Authors: Holton Thérèse A. , Pollastri Gianluca , Shields Denis C. , Mooney Catherine
Published: September 2013

Summary: Cell penetrating peptides (CPPs) are attracting much attention as a means of overcoming the inherently poor cellular uptake of various bioactive molecules. Here, we introduce CPPpred, a web server for the prediction of CPPs using a N-to-1 neural network. The server takes one or more peptide sequences, between 5 and 30 amino acids in length, as input and returns a prediction of how likely each peptide is to be cell penetrating. CPPpred was developed with redundancy reduced training and test sets, offering an advantage over the only other currently available CPP prediction method.

Availability and Implementation: CPPpred is freely available to non-commercial users at http://bioware.ucd.ie/cpppred.

Contact:  Denis.Shields@ucd.ie

Supplementary Information:  Supplementary data are available at Bioinformatics online.
An alignment-free test for recombination
Authors: Haubold Bernhard , Krause Linda , Horn Thomas , Pfaffelhuber Peter
Published: September 2013

Motivation: Why recombination? is one of the central questions in biology. This has led to a host of methods for quantifying recombination from sequence data. These methods are usually based on aligned DNA sequences. Here, we propose an efficient alignment-free alternative.

Results: Our method is based on the distribution of match lengths, which we look up using enhanced suffix arrays. By eliminating the alignment step, the test becomes fast enough for application to whole bacterial genomes. Using simulations we show that our test has similar power as established tests when applied to long pairs of sequences. When applied to 58 genomes of Escherichia coli, we pick up the strongest recombination signal from a 125 kb horizontal gene transfer engineered 20 years ago.

Availability and implementation: We have implemented our method in the command-line program rush. Its C sources and documentation are available under the GNU General Public License from http://guanine.evolbio.mpg.de/rush/.

Contact:  haubold@evolbio.mpg.de

Supplementary information:  Supplementary data are available at Bioinformatics online.
BCov: a method for predicting β-sheet topology using sparse inverse covariance estimation and integer programming
Authors: Savojardo Castrense , Fariselli Piero , Martelli Pier Luigi , Casadio Rita
Published: September 2013

Motivation: Prediction of protein residue contacts, even at the coarse-grain level, can help in finding solutions to the protein structure prediction problem. Unlike α-helices that are locally stabilized, β-sheets result from pairwise hydrogen bonding of two or more disjoint regions of the protein backbone. The problem of predicting contacts among β-strands in proteins has been addressed by several supervised computational approaches. Recently, prediction of residue contacts based on correlated mutations has been greatly improved and finally allows the prediction of 3D structures of the proteins.

Results: In this article, we describe BCov, which is the first unsupervised method to predict the β-sheet topology starting from the protein sequence and its secondary structure. BCov takes advantage of the sparse inverse covariance estimation to define β-strand partner scores. Then an optimization based on integer programming is carried out to predict the β-sheet connectivity. When tested on the prediction of β-strand pairing, BCov scores with average values of Matthews Correlation Coefficient (MCC) and F1 equal to 0.56 and 0.61, respectively, on a non-redundant dataset of 916 protein chains known with atomic resolution. Our approach well compares with the state-of-the-art methods trained so far for this specific task.

Availability and implementation: The method is freely available under General Public License at http://biocomp.unibo.it/savojard/bcov/bcov-1.0.tar.gz. The new dataset BetaSheet1452 can be downloaded at http://biocomp.unibo.it/savojard/bcov/BetaSheet1452.dat.

Contact: piero.fariselli@unibo.it

Supplementary information:  Supplementary data are available at Bioinformatics online.
Photons and particles emitted from cold atmospheric-pressure plasma inactivate bacteria and biomolecules independently and synergistically
Authors: Lackmann Jan-Wilm , Schneider Simon , Edengeiser Eugen , Jarzina Fabian , Brinckmann Steffen , Steinborn Elena , Havenith Martina , Benedikt Jan , Bandow Julia E.
Published: September 2013

Cold atmospheric-pressure plasmas are currently in use in medicine as surgical tools and are being evaluated for new applications, including wound treatment and cosmetic care. The disinfecting properties of plasmas are of particular interest, given the threat of antibiotic resistance to modern medicine. Plasma effluents comprise (V)UV photons and various reactive particles, such as accelerated ions and radicals, that modify biomolecules; however, a full understanding of the molecular mechanisms that underlie plasma-based disinfection has been lacking. Here, we investigate the antibacterial mechanisms of plasma, including the separate, additive and synergistic effects of plasma-generated (V)UV photons and particles at the cellular and molecular levels. Using scanning electron microscopy, we show that plasma-emitted particles cause physical damage to the cell envelope, whereas UV radiation does not. The lethal effects of the plasma effluent exceed the zone of physical damage. We demonstrate that both plasma-generated particles and (V)UV photons modify DNA nucleobases. The particles also induce breaks in the DNA backbone. The plasma effluent, and particularly the plasma-generated particles, also rapidly inactivate proteins in the cellular milieu. Thus, in addition to physical damage to the cellular envelope, modifications to DNA and proteins contribute to the bactericidal properties of cold atmospheric-pressure plasma.
Glassy dynamics in three-dimensional embryonic tissues
Authors: Schötz Eva-Maria , Lanio Marcos , Talbot Jared A. , Manning M. Lisa
Published: September 2013

Many biological tissues are viscoelastic, behaving as elastic solids on short timescales and fluids on long timescales. This collective mechanical behaviour enables and helps to guide pattern formation and tissue layering. Here, we investigate the mechanical properties of three-dimensional tissue explants from zebrafish embryos by analysing individual cell tracks and macroscopic mechanical response. We find that the cell dynamics inside the tissue exhibit features of supercooled fluids, including subdiffusive trajectories and signatures of caging behaviour. We develop a minimal, three-parameter mechanical model for these dynamics, which we calibrate using only information about cell tracks. This model generates predictions about the macroscopic bulk response of the tissue (with no fit parameters) that are verified experimentally, providing a strong validation of the model. The best-fit model parameters indicate that although the tissue is fluid-like, it is close to a glass transition, suggesting that small changes to single-cell parameters could generate a significant change in the viscoelastic properties of the tissue. These results provide a robust framework for quantifying and modelling mechanically driven pattern formation in tissues.
Species loss on spatial patterns and composition of zoonotic parasites
Authors: Harris Nyeema C. , Dunn Robert R.
Published: September 2013

Species loss can result in the subsequent loss of affiliate species. Though largely ignored to date, these coextinctions can pose threats to human health by altering the composition, quantity and distribution of zoonotic parasites. We simulated host extinctions from more than 1300 host–parasite associations for 29 North American carnivores to investigate changes in parasite composition and species richness. We also explored the geography of zoonotic parasite richness under three carnivore composition scenarios and examined corresponding levels of human exposure. We found that changes in parasite assemblages differed among parasite groups. Because viruses tend to be generalists, the proportion of parasites that are viruses increased as more carnivores went extinct. Coextinction of carnivore parasites is unlikely to be common, given that few specialist parasites exploit hosts of conservation concern. However, local extirpations of widespread carnivore hosts can reduce overall zoonotic richness and shift distributions of parasite-rich areas. How biodiversity influences disease risks remains the subject of debate. Our results make clear that hosts vary in their contribution to human health risks. As a consequence, so too does the loss (or gain) of particular hosts. Anticipating changes in host composition in future environments may help inform parasite conservation and disease mitigation efforts.
ETHYLENE-INSENSITIVE3 Is a Senescence-Associated Gene That Accelerates Age-Dependent Leaf Senescence by Directly Repressing miR164 Transcription in Arabidopsis
Authors: Li Zhonghai , Peng Jinying , Wen Xing , Guo Hongwei
Published: September 2013

Numerous endogenous and environmental signals regulate the intricate and highly orchestrated process of plant senescence. Ethylene is a well-known inducer of senescence, including fruit ripening and flower and leaf senescence. However, the underlying molecular mechanism of ethylene-induced leaf senescence remains to be elucidated. Here, we examine ETHYLENE-INSENSITIVE3 (EIN3), a key transcription factor in ethylene signaling, and find that EIN3 is a functional senescence-associated gene. Constitutive overexpression or temporary activation of EIN3 is sufficient to accelerate leaf senescence symptoms. Conversely, loss of EIN3 and EIN3-Like1 (its close homolog) function leads to a delay in age-dependent and ethylene-, jasmonic acid-, or dark-induced leaf senescence. We further found that EIN3 acts downstream of ORESARA2 (ORE2)/ORE3/EIN2 to repress miR164 transcription and upregulate the transcript levels of ORE1/NAC2, a target gene of miR164. EIN3 directly binds to the promoters of microRNA164 (miR164), and this binding activity progressively increases during leaf ageing. Genetic analysis revealed that overexpression of miR164 or knockout of ORE1/NAC2 represses EIN3-induced early-senescence phenotypes. Collectively, our study defines a continuation of the signaling pathway involving EIN2-EIN3-miR164-NAC2 in regulating leaf senescence and provides a mechanistic insight into how ethylene promotes the progression of leaf senescence in Arabidopsis thaliana.
To surrender in dependence of another: the relationship with the ambulance clinicians as experienced by patients
Authors: Holmberg Mats , Forslund Kerstin , Wahlberg Anna Carin , Fagerberg Ingegerd
Published: September 2013

Historically, the ambulance care has focused on acute transports and medical treatment, although ambulance care has also been reported as complex, encompassing more than just medical treatment and transports. Previous studies, on ambulance clinicians, have pointed out the importance of interpersonal caring activities complementary to the medical treatment. Those activities can be understood as taking part in the relationship between patients and ambulance clinicians, earlier described as essential and a core component of care. The aim of this study was to elucidate the meaning of the relationship with the ambulance clinicians as experienced by patients. Twenty ambulance patients were interviewed in the study. The interviews were transcribed verbatim and analysed with a phenomenological hermeneutical method to grasp meanings in the patients' experiences. The regional ethical committee approved the study. In the result emerged one main theme: To surrender in dependence of another. The main theme includes four themes: Being in the hands of another, Being in a caring temporary presence, Being important while involved and Being powerless while insignificant, and the themes comprise eleven subthemes. The main theme meant to have no other option than to surrender and to put their life into the hand of another. This surrender also meant to adapt to the clinicians' views even if not shared. This is experienced as excessive care. Summarised, the patients' experiences were both positive and negative and the findings provide a complex understanding of the relationship between the patient and the ambulance clinicians. Overall, the relationship embraces the whole person without reducing the patient to be a recipient of an objectified ambulance care.
Miller-Cycle Regulatable, Two-Stage Turbocharging System Design for Marine Diesel Engines
Authors: Cui Yi , Hu Zhilong , Deng Kangyao , Wang Qifu
Published: September 2013

The increasingly stringent NOx emission regulations of the International Marine Organization (IMO) have demanded new design concepts and architectures for diesel engines. The Miller cycle, which reduces the in-cylinder combustion temperature by reducing the effective compression ratio, is the principal measure used for reducing NOx specific emissions; however, this is at the cost of volumetric efficiency and engine power. Therefore, it is essential to combine the Miller cycle with a highly boosted turbocharging system, two-stage turbocharging for example, to recover the power. While much work has been done in the development of Miller-cycle regulatable two stage turbocharging system for marine diesel engines, there are nonetheless few, if any, thorough discussions on system optimization and performance comparison. This study presents a theoretical optimization design process for a Miller-cycle regulatable, two-stage turbocharging system for marine diesel engines. First, the different scenarios and regulation methods of two-stage turbocharging systems are compared according to the system efficiency and equivalent turbine flow characteristics. Then, a multizone combustion model based on a one-dimensional cycle simulation model is established and used for the optimization of valve timings according to the IMO NOx emission limits and fuel efficiencies. The high- and low-stage turbochargers are selected by an iterative matching method. Then, the control strategies for the boost air and high-stage turbine bypass valves are also studied. As an example, a Miller-cycle regulatable, two-stage turbocharging system is designed for a highly boosted high-speed marine diesel engine. The results show that NOx emissions can be reduced by 30% and brake specific fuel consumption (BSFC) can also be improved by a moderate Miller cycle combined with regulatable two-stage turbocharging.
Priming Designers to Communicate Sustainability
Authors: She Jinjuan , MacDonald Erin
Published: September 2013

Priming is a psychological experimental technique that uses an artifact, exposure, or experience to stimulate cognitive accessibility of specific mental content. Design techniques that use priming stimuli have thus far focused on generating more features, novel features, and relevant features and addressing latent customer needs. This article presents a design technique that uses priming specifically to help designers to communicate sustainability via design at an early stage in the design process. The authors have determined that sustainable products face a special challenge in the market because thoughtful sustainability features such as decreased energy usage, use of recycled materials, or manufacturing considerations are sometimes “hidden” from the customer. As green marketing messages are not always trusted, another approach is to communicate sustainability to the customer through product features. We propose and test a new design technique that uses psychological priming to help designers generate product features that communicate sustainability to the customer. The technique involves performing a sensory-and-sustainability-heightening activity before generating ideas for product features. We investigate priming stimuli in the form of a questionnaire and a collage activity and compare these techniques along with other existing priming-based techniques to a control condition. The new technique is proven to be more effective in helping designers generate product features that communicate sustainability, as judged by both experts and consumers.
Spectral Characterization of Hierarchical Modularity in Product Architectures1
Authors: Sarkar Somwrita , Dong Andy , Henderson James A. , Robinson P. A.
Published: September 2013

Despite the importance of the architectural modularity of products and systems, existing modularity metrics or algorithms do not account for overlapping and hierarchically embedded modules. This paper presents a graph theoretic spectral approach to characterize the degree of modular hierarchical-overlapping organization in the architecture of products and complex engineered systems. It is shown that the eigenvalues of the adjacency matrix of a product architecture graph can reveal layers of hidden modular or hierarchical modular organization that are not immediately visible in the predefined architectural description. We use the approach to analyze and discuss several design, management, and system resilience implications for complex engineered systems.
High Dimensional Model Representation With Principal Component Analysis
Authors: Hajikolaei Kambiz Haji , Gary Wang G.
Published: September 2013

In engineering design, spending excessive amount of time on physical experiments or expensive simulations makes the design costly and lengthy. This issue exacerbates when the design problem has a large number of inputs, or of high dimension. High dimensional model representation (HDMR) is one powerful method in approximating high dimensional, expensive, black-box (HEB) problems. One existing HDMR implementation, random sampling HDMR (RS-HDMR), can build an HDMR model from random sample points with a linear combination of basis functions. The most critical issue in RS-HDMR is that calculating the coefficients for the basis functions includes integrals that are approximated by Monte Carlo summations, which are error prone with limited samples and especially with nonuniform sampling. In this paper, a new approach based on principal component analysis (PCA), called PCA-HDMR, is proposed for finding the coefficients that provide the best linear combination of the bases with minimum error and without using any integral. Several benchmark problems of different dimensionalities and one engineering problem are modeled using the method and the results are compared with RS-HDMR results. In all problems with both uniform and nonuniform sampling, PCA-HDMR built more accurate models than RS-HDMR for a given set of sample points.
Prediction of the Onset of Flow Instability in a Single Horizontal Microtube With an Inlet Orifice
Authors: Fan YanFeng , Hassan Ibrahim
Published: September 2013

A methodology to predict the onset of flow instability (OFI) in a single horizontal microtube with an inlet orifice is developed based on the predication of pressure drop. The predictive methodology states, for the same flow rate, the flow instability occurs as the single-phase liquid pressure drop under no heating condition equals the two-phase pressure drop under heating condition in a single microtube. The addition of inlet orifice increases the heat flux at the onset of flow instability by increasing the upstream pressure. The present methodology is validated by comparing the predicted heat flux at the onset of flow instability with our previous experimental data in the microtubes with three sizes of inlet orifices. The results show that the present method can predict the heat flux at the onset of flow instability with a deviation of 30% and mean absolute error of 13% at mass fluxes from 700 to 3000 kg/m2 s. The effects of inlet orifice size and saturation pressure on the onset of flow instability are also studied based on the present methodology. It is found that, at mass fluxes from 100 to 2000 kg/m2 s, the area ratio less than 15% eliminates the flow instability completely before the critical heat flux occurs.
Pilot Scale Demonstration of a 100-kWth Solar Thermochemical Plant for the Thermal Dissociation of ZnO
Authors: Villasmil W. , Brkic M. , Wuillemin D. , Meier A. , Steinfeld A.
Published: September 2013

A solar-driven thermochemical pilot plant for the high-temperature thermal dissociation of ZnO has been designed, fabricated, and experimentally demonstrated. Tests were conducted at the large-scale solar concentrating facility of PROMES-CNRS by subjecting the solar reactor to concentrated radiative fluxes of up to 4477 suns and peak solar radiative power input of 140 kWth. The solar reactor was operated at temperatures up to 1936 K, yielding a Zn molar fraction of the condensed products in the range 12–49% that was largely dependent on the flow rate of Ar injected to quench the evolving gaseous products.
Product Resynthesis: Knowledge Discovery of the Value of End-of-Life Assemblies and Subassemblies
Authors: Woo Kang Sung , Sane Chinmay , Vasudevan Nitish , Tucker Conrad S.
Published: September 2013

The trends of increasing waste and comparatively low growth of waste treatment methodologies have created the need for better utilization of the products we deem unfit for use. The options available for utilizing end-of-life (EOL) products are currently restricted to reusing, recycling, remanufacturing, and permanent disposal. In this work, the authors propose a new EOL option called resynthesis that utilizes existing waste from EOL products in a novel way through the synthesis of assemblies/subassemblies across multiple domains (i.e., consumer electronics, health care, automotive, etc.). The resynthesis of assemblies/subassemblies is achieved by quantifying their similarities (form and function) across multiple domains. A mixed-integer linear model is developed to determine the optimal EOL strategy for each component/subassembly. As a means of verifying the EOL decision, the value of the “new” resynthesized product is compared with the value that would be derived if the individual subassemblies were reused, remanufactured, recycled, or disposed. A case study involving an electronic mouse is used to validate the proposed methodology and to demonstrate its practicality as an alternate enterprise level EOL option.
Using a Stack Shunt to Mitigate Catalyst Support Carbon Corrosion in Polymer Electrolyte Membrane Fuel Cell Stacks During Start-Stop Cycling
Authors: Bona Denis , Curtin Dennis E. , Pedrazzo Francesco , Tresso Elena Maria
Published: September 2013

Carbon black based electrodes are generally recognized as state of the art for PEM fuel cell technology due to the high performance achieved with a relatively low Pt content. However, the catalyst carbon support is prone to carbon oxidation. This leads to a loss of the catalyst area and overall performance, along with a higher mass transport loss due to an increased flooding tendency. This phenomenon is particularly severe when the fuel cell experiences repetitive start-stop cycles. Therefore, specific countermeasures against catalyst layer carbon oxidation are required, especially for automotive and backup power applications, where the startup/shutdown rate is considerably high. The authors evaluated a basic design that uses a stack shunt. A properly modified control protocol, which includes the stack shunt, is able to avoid high cathode potential peaks, which are known to accelerate catalyst carbon support corrosion and its negative effects. During two separate durability tests, one adopting the shunt design and another using nonprotected shutdown, a 24-cell stack was subjected to continuous starts and stops for several months and its performance constantly monitored. The results show that when the shunt is used, there is a 37% reduction in the voltage degradation rate for each startup/shutdown cycle and a two-fold increase in the number of startup/shutdown cycles before an individual cell reached the specified “end of life” voltage criteria. Furthermore, ex situ FE-SEM analysis revealed cathode catalyst layer thinning, which is an indication that the emerging degradation mechanism is the catalyst support carbon corrosion, as expected. This provides further support that the constant voltage degradation rate typically experienced in PEMFCs can be primarily attributed to the catalyst support carbon corrosion rate. The proposed shunt protocol is very cost effective and does not require any substantial changes in the system. For this reason, its adoption is recommended as a viable method to decrease the catalyst support carbon corrosion rate and extend the operating life of the PEMFC stack.