bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Faltering Solid Organ Donor Pool in the United States (2001–2010)
Authors: Saidi Reza F. , Markmann James F. , Jabbour Nicolas , Li YouFu , Shah Shimul A. , Cosimi A. B. , Bozorgzadeh Adel 
Published: August 2012

AbstractBackgroundOrgan shortage is the greatest challenge facing the field of organ transplantation today. Use of more organs of marginal quality has been advocated to address the shortage.MethodWe examined the pattern of donation and organ use in the United States as shown in the Organ Procurement and Transplantation Network/United Network for Organ Sharing database of individuals who were consented for and progressed to organ donation between January 2001 and December 2010.ResultsThere were 66,421 living donors and 73,359 deceased donors, including 67,583 (92.1 %) identified as donation after brain death and 5,776 (7.9 %) as donation after circulatory death (DCD). Comparing two periods, era 1 (01/2001–12/2005) and era 2 (01/2006–12/2010), the number of deceased donors increased by 20.3 % from 33,300 to 40,059 while there was a trend for decreasing living donation. The DCD subgroup increased from 4.9 to 11.7 % comparing the two eras. A significant increase in cardiovascular/cerebrovascular disease as a cause of death was also noted, from 38.1 % in era 1 to 56.1 % in era 2 (p < 0.001), as was a corresponding decrease in the number of deaths due to head trauma (48.8 vs. 34.9 %). The overall discard rate also increased from 13,411 (11.5 %) in era 1 to 19,516 (13.7 %) in era 2. This increase in discards was especially prominent in the DCD group [440 (20.9 %) in era 1 vs. 2,089 (24.9 %) in era 2].ConclusionsWe detect a significant change in pattern of organ donation and use in the last decade in the United States. The transplant community should consider every precaution to prevent the decay of organ quality and to improve the use of marginal organs.
Relationships among Teachers’ Knowledge and Beliefs Regarding the Teaching of Evolution: A Case for Turkey
Authors: Tekkaya Ceren , Akyol Gülsüm , Sungur Semra 
Published: August 2012

Abstract
The research study investigated the possible associations among science and biology teachers’ knowledge and belief variables concerning teaching evolution in science and biology classes. Specifically, this study examined how a set of variables including teachers’ understanding of evolution and nature of science (NOS) is related to the set of variables including teachers’ acceptance of evolution and perceptions of teaching evolution (i.e., perceptions of the necessity of addressing evolution in their classrooms, perceptions of the factors that impede addressing evolution in their classrooms, and personal science teaching efficacy beliefs regarding evolution). Data were collected from science and biology teachers through administration of Evolution Content Knowledge Test, Measure of Acceptance of the Theory of Evolution, Nature of Science as Argument Questionnaire and Teachers’ Perceptions of Teaching Evolution Scale. Canonical correlation analysis findings suggested that teachers who had thorough understanding of evolution and NOS were likely to both accept the scientific validity of evolution and believe the necessity of addressing evolution in the classrooms. On the other hand, teachers with thorough understanding of evolution and NOS did not necessarily believe that they have a stronger sense of self-efficacy beliefs regarding teaching evolution and that there are fewer obstacles to addressing evolution in the classroom. The research is significant in that it provides empirical evidence clarifying the interactions between teachers’ understanding and beliefs in teaching evolution. Implications for science teacher education are discussed.
A direct numerical simulation study of turbulence and flame structure in transverse jets analysed in jet-trajectory based coordinates
Authors: Grout R. W. , Gruber A. , Kolla H. , Bremer P.-T. , Bennett J. C. , Gyulassy A. , Chen J. H. 
Published: August 2012

AbstractAn${\mathrm{H} }_{2} / {\mathrm{N} }_{2} $jet in cross-flow (JICF) of air is studied using three-dimensional direct numerical simulation with and without chemical reaction in order to investigate the role of the complex JICF turbulent flow field in the mechanism of fast fuel-oxidant mixing and of aerodynamic flame stabilization in the near field of the jet nozzle. Focus is on delineating the flow/mixing/chemistry conditions that are necessary and/or sufficient to achieve flame anchoring that ultimately enables the formulation of more reliable and precise guidelines for design of fuel injection nozzles. A mixture averaged diffusion formulation that includes the effect of thermal diffusion is used along with a detailed chemical kinetics mechanism for hydrogen–air combustion. A new parametrization technique is used to describe the jet trajectory: solution of Laplace’s equation upon, and then within, an opportune scalar surface anchored by Dirichlet boundary conditions at the jet nozzle and plume exit from the domain provides a smoothly varying field along the jet path. The surface is selected to describe the scalar mixing and reaction associated with a transverse jet. The derived field,$j(\mathbi{x})$, is used as a condition to mark the position along the natural jet trajectory when analysing the variation of relevant flow, mixing and reaction quantities in the present direct numerical simulation (DNS) datasets. Results indicate the presence of a correlation between the flame base location in parameter space and a region of low velocity magnitude, high enstrophy, high mixing rate and high equivalence ratio (flame root region). Instantaneously, a variety of vortical structures, well known from the literature as important contributors to fuel-oxidant mixing, are observed in both inert and reactive cases with a considerable span in length scales. Moreover, instantaneous plots from reactive cases illustrate that the most upstream flame tongues propagate close to the trailing edge of the fuel jet potential core near the jet shear layer vortex shedding position. Some degree of asymmetry with respect to the domain mid-plane in the spanwise direction is observed in the averaged fields, both for the inert and reactive cases.
Feedback control of cavity flow oscillations using simple linear models
Authors: Illingworth Simon J. , Morgans Aimee S. , Rowley Clarence W. 
Published: August 2012

AbstractUsing data from direct numerical simulations, linear models of the compressible flow past a rectangular cavity are found. The emphasis is on forming simple models which capture the input–output behaviour of the system, and which are useful for feedback controller design. Two different approaches for finding a linear model are investigated. The first involves using input–output data of the linearized cavity flow to form a balanced, reduced-order model directly. The second approach is conceptual, and involves modelling each element of the flow physics separately using simple analytical expressions, the parameters of which are chosen based on simulation data at salient points in the cavity’s computational domain. Both models are validated: first in the time domain by comparing their impulse responses to that of the full system in direct numerical simulations; and second in the frequency domain by comparing their frequency responses. Finally, the validity of both linear models is shown most clearly by using them for feedback controller design, and then applying each controller in direct numerical simulations. Both controllers completely eliminate oscillations, and demonstrate the advantages of model-based feedback controllers, even when the models upon which they are based are very simple.
Direct numerical simulation of premixed flame boundary layer flashback in turbulent channel flow
Authors: Gruber A. , Chen J. H. , Valiev D. , Law C. K. 
Published: August 2012

AbstractDirect numerical simulations are performed to investigate the transient upstream propagation (flashback) of premixed hydrogen–air flames in the boundary layer of a fully developed turbulent channel flow. Results show that the well-known near-wall velocity fluctuations pattern found in turbulent boundary layers triggers wrinkling of the initially flat flame sheet as it starts propagating against the main flow direction, and that the structure of the characteristic streaks of the turbulent boundary layer ultimately has an important impact on the resulting flame shape and on its propagation mechanism. It is observed that the leading edges of the upstream-propagating premixed flame are always located in the near-wall region of the channel and assume the shape of several smooth, curved bulges propagating upstream side by side in the spanwise direction and convex towards the reactant side of the flame. These leading-edge flame bulges are separated by thin regions of spiky flame cusps pointing towards the product side at the trailing edges of the flame. Analysis of the instantaneous velocity fields clearly reveals the existence, on the reactant side of the flame sheet, of backflow pockets that extend well above the wall-quenching distance. There is a strong correspondence between each of the backflow pockets and a leading edge convex flame bulge. Likewise, high-speed streaks of fast flowing fluid are found to be always colocated with the spiky flame cusps pointing towards the product side of the flame. It is suggested that the origin of the formation of the backflow pockets, along with the subsequent mutual feedback mechanism, is due to the interaction of the approaching streaky turbulent flow pattern with the Darrieus–Landau hydrodynamic instability and pressure fluctuations triggered by the flame sheet. Moreover, the presence of the backflow pockets, coupled with the associated hydrodynamic instability and pressure–flow field interaction, greatly facilitate flame propagation in turbulent boundary layers and ultimately results in high flashback velocities that increase proportionately with pressure.
Novel microsatellite DNA markers indicate strict parthenogenesis and few genotypes in the invasive willow sawflyNematus oligospilus
Authors: Caron V. , Norgate M. , Ede F.J. , Nyman T. , Sunnucks P. 
Published: August 2012

AbstractInvasive organisms can have major impacts on the environment. Some invasive organisms are parthenogenetic in their invasive range and, therefore, exist as a number of asexual lineages (=clones). Determining the reproductive mode of invasive species has important implications for understanding the evolutionary genetics of such species, more especially, for management-relevant traits. The willow sawflyNematus oligospilusFörster (Hymenoptera: Tenthredinidae) has been introduced unintentionally into several countries in the Southern Hemisphere where it has subsequently become invasive. To assess the population expansion, reproductive mode and host-plant relationships of this insect, microsatellite markers were developed and applied to natural populations sampled from the native and expanded range, along with sequencing of the cytochrome-oxidase I mitochondrial DNA (mtDNA) region. Other tenthredinids across a spectrum of taxonomic similarity toN. oligospilusand having a range of life strategies were also tested. Strict parthenogenesis was apparent within invasiveN. oligospiluspopulations throughout the Southern Hemisphere, which comprised only a small number of genotypes. Sequences of mtDNA were identical for all individuals tested in the invasive range. The microsatellite markers were used successfully in several sawfly species, especiallyNematusspp. and other genera of the Nematini tribe, with the degree of success inversely related to genetic divergence as estimated from COI sequences. The confirmation of parthenogenetic reproduction inN. oligospilusand the fact that it has a very limited pool of genotypes have important implications for understanding and managing this species and its biology, including in terms of phenotypic diversity, host relationships, implications for spread and future adaptive change. It would appear to be an excellent model study system for understanding evolution of invasive parthenogens that diverge without sexual reproduction and genetic recombination.
Clandestine Recruitment Networks in the Bight of Biafra: Fernando Pó's Answer to the Labour Question, 1926–1945
Authors: Martino Enrique 
Published: August 2012

SummaryThe “Labour Question”, a well-known obsession pervading the archives of Africa, was posed by colonial rulers as a calculated question of scarcity and coercion. On the Spanish plantation island of Fernando Pó the shortage and coercive recruitment of labour was particularly intense. This article examines two distinct clandestine labour recruitment operations that took hold of Rio Muni and eastern Nigeria, on the east and the north of the Bight of Biafra. The trails of the recruitment networks were successfully constructed by the specifically aligned “mediators” of kinship, ethnicity, money, law, commodities, and administration. The conceptual focus on flat “mediators” follows Bruno Latour's sociology of associations and has been set against the concept of an “intermediary” that serves to join and uphold the structure/agency and global/local binaries.
Synchronous spontaneous cerebrospinal fluid leaks in the nose and ear
Authors: Schraven S P , Bisdas S , Wagner W 
Published: August 2012

AbstractObjective:The majority of spontaneous cerebrospinal fluid leaks occur at the anterior skull base; few cases at the temporal bone have been described. There have been no previous reports of synchronous leaks at the anterior skull base and temporal bone in the same patient.Methods:Case report and brief review of management of spontaneous cerebrospinal fluid leaks in the nose and ear.Case report:A 34-year-old, pregnant woman presented with watery nasal discharge and unilateral middle-ear effusion. The nasal and ear secretions both proved to be cerebrospinal fluid. Radiological imaging showed defects in both the ethmoid roof and the mastoid roof (middle cranial fossa). These defects were surgically closed using duraplasties.Conclusion:A literature review indicated that this is the first reported case of synchronous spontaneous cerebrospinal fluid leaks via the anterior skull base and temporal bone.
Shifted risk preferences in pathological gambling
Authors: Ligneul R. , Sescousse G. , Barbalat G. , Domenech P. , Dreher J.-C. 
Published: August 2012

BackgroundPathological gambling (PG) is an impulse control disorder characterized by excessive monetary risk seeking in the face of negative consequences. We used tools from the field of behavioral economics to refine our description of risk-taking behavior in pathological gamblers. This theoretical framework allowed us to confront two hypotheses: (1) pathological gamblers distort winning probabilities more than controls; and (2) pathological gamblers merely overweight the whole probability range.MethodEighteen pathological gamblers and 20 matched healthy participants performed a decision-making task involving choices between safe amounts of money and risky gambles. The online adjustment of safe amounts, depending on participants' decisions, allowed us to compute ‘certainty equivalents’ reflecting the subjective probability weight associated with each gamble. The behavioral data were then fitted with a mathematical function known as the ‘probability weighting function’, allowing us to disentangle our two hypotheses.ResultsThe results favored the second hypothesis, suggesting that pathological gamblers' behavior reflects economic preferences globally shifted towards risk, rather than excessively distorted probability weighting. A mathematical parameter (elevation parameter) estimated by our fitting procedure was found to correlate with gambling severity among pathological gamblers, and with gambling affinity among controls.ConclusionsPG is associated with a specific pattern of economic preferences, characterized by a global (i.e. probability independent) shift towards risky options. The observed correlation with gambling severity suggests that the present ‘certainty equivalent’ task may be relevant for clinical use.
Towards a universal model of reading
Authors: Frost Ram 
Published: August 2012

AbstractIn the last decade, reading research has seen a paradigmatic shift. A new wave of computational models of orthographic processing that offer various forms of noisy position or context-sensitive coding have revolutionized the field of visual word recognition. The influx of such models stems mainly from consistent findings, coming mostly from European languages, regarding an apparent insensitivity of skilled readers to letter order. Underlying the current revolution is the theoretical assumption that the insensitivity of readers to letter order reflects the special way in which the human brain encodes the position of letters in printed words. The present article discusses the theoretical shortcomings and misconceptions of this approach to visual word recognition. A systematic review of data obtained from a variety of languages demonstrates that letter-order insensitivity isneithera general property of the cognitive systemnora property of the brain in encoding letters. Rather, it is avariantand idiosyncratic characteristic of some languages, mostly European, reflecting a strategy of optimizing encoding resources, given the specific structure of words. Since the main goal of reading research is to develop theories that describe thefundamental and invariantphenomena of reading across orthographies, an alternative approach to model visual word recognition is offered. The dimensions of a possible universal model of reading, which outlines the common cognitive operations involved in orthographic processing in all writing systems, are discussed.
Consideration of the linguistic characteristics of letters makes the universal model of reading more universal
Authors: Kim Kyungil , Lee Chang H. , Lee Yoonhyoung 
Published: August 2012

AbstractWe suggest that the linguistic characteristics of letters also need to be considered to fully understand how a reader processes printed words. For example, studies in Korean showed that unambiguity in the assignment of letters to their appropriate onset, vowel, or coda slot is one of the main sources of the letter-transposition effect. Indeed, the cognitive system that processes Korean is tuned to the structure of the Korean writing system.
What and where is the word?
Authors: McBride-Chang Catherine , Chen Hsuan-Chih , Kasisopa Benjawan , Burnham Denis , Reilly Ronan , Leppänen Paavo 
Published: August 2012

AbstractExamples from Chinese, Thai, and Finnish illustrate why researchers cannot always be confident about the precise nature of the word unit. Understanding ambiguities regarding where a word begins and ends, and how to model word recognition when many derivations of a word are possible, is essential for universal theories of reading applied to both developing and expert readers.
Flashing out or fleshing out? A developmental perspective on a universal model of reading
Authors: Homer Bruce D. , Miller Russell , Donnelly Seamus 
Published: August 2012

AbstractThe principles for universal reading models proposed by Frost correspond to developmental theories, in which neurocognitive constraints and cultural experiences shape development. We question his contention that Hebrew word identification is fundamentally about roots, excluding verbal and nominal word-pattern morphemes; and we propose that readers use all information available in stimuli, adjusting for volume and usefulness.
The limitations of the reverse-engineering approach to cognitive modeling
Authors: Rueckl Jay G. 
Published: August 2012

AbstractFrost's critique reveals the limitations of the reverse-engineering approach to cognitive modeling – the style of psychological explanation in which a stipulated internal organization (in the form of a computational mechanism) explains a relatively narrow set of phenomena. An alternative is to view organization as both the explanation for some phenomena and a phenomenon to be explained. This move poses new and interesting theoretical challenges for theories of word reading.
Frost and fogs, or sunny skies? Orthography, reading, and misplaced optimalism
Authors: Share David L. 
Published: August 2012

AbstractI argue that the study of variability rather than invariance should head the reading research agenda, and that strong claims of orthographic “optimality” are unwarranted. I also expand briefly on Frost's assertion that an efficient orthography must represent sound and meaning, by considering writing systems as dual-purpose devices that must provide decipherability for novice readers and automatizability for the expert.
A universal approach to modeling visual word recognition and reading: Not only possible, but also inevitable
Authors: Frost Ram 
Published: August 2012

AbstractI have argued that orthographic processing cannot be understood and modeled without considering the manner in which orthographic structure represents phonological, semantic, and morphological information in a given writing system. A reading theory, therefore, must be a theory of the interaction of the reader with his/her linguistic environment. This outlines a novel approach to studying and modeling visual word recognition, an approach that focuses on the common cognitive principles involved in processing printed words across different writing systems. These claims were challenged by several commentaries that contested the merits of my general theoretical agenda, the relevance of the evolution of writing systems, and the plausibility of finding commonalities in reading across orthographies. Other commentaries extended the scope of the debate by bringing into the discussion additional perspectives. My response addresses all these issues. By considering the constraints of neurobiology on modeling reading, developmental data, and a large scope of cross-linguistic evidence, I argue that front-end implementations of orthographic processing that do not stem from a comprehensive theory of the complex information conveyed by writing systems do not present a viable approach for understanding reading. The common principles by which writing systems have evolved to represent orthographic, phonological, and semantic information in a language reveal the critical distributional characteristics of orthographic structure that govern reading behavior. Models of reading should thus be learning models, primarily constrained by cross-linguistic developmental evidence that describes how the statistical properties of writing systems shape the characteristics of orthographic processing. When this approach is adopted, a universal model of reading is possible.