bluuebunny/crossref_metadata_2025 huggingface dataset:
Social influence and the diamond model of social response: Toward an extended theory of informational influence
Authors: Nail Paul R. , Ruch Gregory Lynn
Published: December 2011

According to the diamond model of social response (Nail, 1989; Willis, 1965), a bidimensional response space is necessary to provide for the possible responses in social influence settings. Experiment 1 tested diamond model predictions in a context that simulated social influence processes. Evidence was found for each of the responses postulated by the diamond model: conformity, anticonformity, independence and self‐anti‐conformity. The descriptive constructs of the diamond model were shown to correspond to an extended version of the explanatory constructs of Deutsch & Gerard's (1955) theory of informational influence. Experiment 2 tested this extended theory in a setting with greater experimental realism than Expt 1. Interestingly, Expt 2 found evidence for informational influence: conformity, independence and self‐anticonformity, but not informational anticonformity. Overall, the data support the bidimensional diamond model over any of the competing unidimensional formulations.
False consensus and out‐group homogeneity: A methodological note on their relationship
Authors: Ryan Carey S. , Judd Charles M.
Published: December 2011

Two different lines of research in social psychology ask subjects to generate estimates of the percentage of group members who they think would espouse some position or make some behavioural choice. Research on the false consensus effect has shown that such estimates are influenced by the subject's own choice. Research on out‐group homogeneity has shown that such estimates are higher for group stereotypic choices than counterstereotypic ones and that this difference in turn is more pronounced for out‐groups than in‐groups. In this article we explore the relationship between these two effects, both of which rely on the same dependent measure. We show that out‐group homogeneity will be estimated with bias unless the subject's own choice is included as a factor in the analysis, whenever false consensus is present and whenever the two target groups differ in the prevalence of their actual choices. We demonstrate this confounding with both hypothetical and actual data.
Perceived material wealth and first impressions
Authors: Dittmar Helga
Published: December 2011

This study explores the significance of material possessions and wealth when people form first impressions of others' identities. Two theoretical perspectives suggest different kinds of social information respondents may draw on when making inferences about a person in a material context: (1) the intergroup relations approach focuses on similarity in socio‐economic background between perceiver and target, and (2) dominant representations underline the importance of a societally shared, consensual frame of reference about the relation between wealth and identity. One hundred and twelve adolescents (half) attending private schools, half a state school with a working‐class catchment area) were shown one of four videos which depicted the same woman or man in either affluent or less privileged material circumstances. Respondents' evaluations of the video target's personal qualities and their judgements about the similarity between the material setting in the video and their home environment were analysed by MANOVAs. Findings support the dominant representations approach, whereas perceived similarity in socioeconomic background did not influence impressions. These results are discussed in terms of ‘ideological’ representations about material context and identity, and their implications for social identity theory.
An integration of Gibsonian and Vygotskian perspectives on changing attitudes in group contexts
Authors: Baron Reuben M. , Misovich Stephen J.
Published: December 2011

Lewin's proposition that it is easier to change people as part of a group than as isolated individuals is given a systems or niche level interpretation in terms of an integration of Vygotskian‐Gibsonian perspectives. Vygotsky's Zone of Proximal Development (ZPD) concept is given an equivalent within the attitude realm in regard to a group‐mediated Zone of Potential Change (ZPC). The ZPC is in turn given an ecological elaboration in terms of how concepts such as affordances and attunements may be used to clarify at a process level the role of groups in modifying members' objects of judgement. The Vygotskian concept of activity is used throughout as a means of integrating these approaches in regard to treating change as a system level property of groups.
Feedback seeking in groups: A theoretical perspective
Authors: Robinson Sandra , Weldon Elizabeth
Published: December 2011

The concept of feedback seeking proposed by Ashford & Cummings (1983) is extended by considering the process of feedback seeking when people work in groups. Three issues are considered. First, motives that underlie feedback seeking in groups are identified. Second, the impact of each motive on the level of feedback sought (individual or group); the decision to seek feedback from other group members, people outside the group or from a non‐human source; and the decision to seek information publicly or privately are described. Third, implications of feedback seeking for group effectiveness are discussed.
Gaining turns and achieving high influence ranking in small conversational groups*
Authors: Ng Sik Hung , Bell Dean , Brooke Mark
Published: December 2011

Unacquainted subjects, in groups of four or five, viewed and then discussed a television programme on the topic of homosexuality. Afterwards, they ranked each group member in terms of how influential the member had been during the discussion. High‐ranking members, compared to low‐ranking members, had a greater proportion of aggregate speaking turns, thus replicating Brooke & Ng's (1986) finding. Aggregate turns were then divided into turns gained by interruptive or non‐interruptive means; and the two turn types were used to predict influence ranking in an attempt to test the idea that turns were a resource for achieving influence regardless of how they were gained. Supportive results were found: interruption‐turns, like non‐interruption‐turns, reliably predicted influence ranking. For reasons yet to be tested, interruption‐turns were in fact superior to non‐interruption‐turns for predicting influence ranking.
Repetitive activity slows axonal conduction velocity and concomitantly increases mechanical activation threshold in single axons of the rat cranial dura
Authors: De Col Roberto , Messlinger Karl , Carr Richard W.
Published: December 2011

Non‐technical summary  Primary sensory neurones with unmyelinated axons signal touch, temperature, pain and itch. A peculiar feature of these axons is their pronounced slowing of axonal conduction velocity seen at low frequencies (<2 Hz) as a progressive walking of the action potential response latency to electrical stimulation. In human microneurographic recordings, the magnitude of latency walking can be used to predict an individual axon's sensitivity to thermal and mechanical stimuli. Recently, activity‐dependent inactivation of voltage‐gated sodium channels (NaV) has been shown to contribute to latency walking implying that NaV‐dependent processes such as action potential initiation may also be affected. This was tested here using dynamic mechanical stimuli. Precise determination of mechanical activation threshold in single axons revealed that conduction velocity slowing during repetitive activity was paralleled by an increase in threshold. This suggests that activity‐induced axonal slowing represents a form of accommodation limiting excessive firing in unmyelinated sensory axons.
Augmented single‐unit muscle sympathetic nerve activity in heart failure with chronic atrial fibrillation
Authors: Ikeda Tatsunori , Murai Hisayoshi , Kaneko Shuichi , Usui Soichiro , Kobayashi Daisuke , Nakano Manabu , Ikeda Keiko , Takashima Shin‐ichiro , Kato Takeshi , Okajima Masaki , Furusho Hiroshi , Takamura Masayuki
Published: December 2011

Non‐technical summary  Augmentation of sympathetic nerve activity plays an important role in the deterioration of heart failure (HF). Atrial fibrillation (AF) is a well known and common complication in chronic HF. However, it remains unclear the relationship between sympathetic nerve activity and irregular ventricular rhythm induced by AF in HF. We examined the different sympathetic firing characteristics between HF patients with and without AF using a single‐unit muscle sympathetic nerve activity (MSNA) method, which is a newly developed assessment of direct recording of sympathetic nerve activity. The firing frequency of single‐unit MSNA was increased in HF patients with AF compared with HF patients without AF; particularly, those with a prolonged long RR interval showed multiple firings of single‐unit MSNA. More intense single‐unit MSNA within one cardiac interval occurred in HF patients with AF than patients without AF, even in AF patients receiving heart rate control therapy. Accordingly, our results suggest that AF per se augments central sympathetic activity and the restoration of sinus rhythm may be more effective in the treatment of HF patients with AF.
Design of Honeycombs for Modulus and Yield Strain in Shear
Authors: Ju Jaehyung , Summers Joshua D. , Ziegert John , Fadel George
Published: December 2011

The low in-plane modulus of honeycombs may be used for compliant structures with a high elastic limit while maintaining a required modulus. Numerical and finite element (FE) studies for a functional design of honeycombs having a high shear strength, (τpl*)12 and a high shear yield strain, (γpl*)12 are conducted with two material selections—mild-steel (MS) and polycarbonate (PC) and five honeycomb configurations, when they are designed to be a target shear modulus, G12* of 6.5 MPa. A numerical study of cellular materials theory is used to explore the elastic limit of honeycombs. FE analysis is also employed to validate the numerical study. Cell wall thicknesses are found for each material to reach the target G12* for available cell heights with five honeycomb configurations. Both MS and PC honeycombs can be tailored to have the G12* of 6.5 MPa with 0.1–0.5 mm and 0.3–2.2 mm cell wall thicknesses, respectively, depending on the number of vertical stacks, N. The PC auxetic honeycomb with θ= −20 deg shows high shear flexibility, when honeycombs are designed to be the G12* of 6.5 MPa; a 0.72 MPa (τpl*)12 and a 13% (γpl*)12. The authors demonstrate a functional design with cellular materials with a large design space through the control of both material and geometry to generate a shear flexible property.
Design, Analysis, and Evaluation of the UC-Berkeley Wave-Energy Extractor
Authors: Yeung Ronald W. , Peiffer Antoine , Tom Nathan , Matlak Tomasz
Published: December 2011

This paper evaluates the technical feasibility and performance characteristics of an ocean-wave energy to electrical energy conversion device that is based on a moving linear generator. The UC-Berkeley design consists of a cylindrical floater, acting as a rotor, which drives a stator consisting of two banks of wound coils. The performance of such a device in waves depends on the hydrodynamics of the floater, the motion of which is strongly coupled to the electromagnetic properties of the generator. Mathematical models are developed to reveal the critical hurdles that can affect the efficiency of the design. A working physical unit is also constructed. The linear generator is first tested in a dry environment to quantify its performance. The complete physical floater and generator system is then tested in a wave tank with a computer-controlled wavemaker. Measurements are compared with theoretical predictions to allow an assessment of the viability of the design and the future directions for improvements.
Fatigue Assessment of Welded Joints Taking Into Account Effects of Residual Stress
Authors: Syahroni Nur , Berge Stig
Published: December 2011

Residual stress may have a significant effect on the fatigue strength of welded joints. As a nonfluctuating stress, it has an effect similar to that of the mean stress. Recently the International Association of Ship Classification Societies (IACS) has issued Common Structural Rules (CSR) for respectively tankers and bulk carriers. The effect of mean stress in fatigue design is taken into account in both sets of rules. However, the treatment is quite different, in particular with regard to residual stress and shakedown effects. In the present paper a comparative study of fatigue design procedures of the IACS rules is reported, with emphasis on residual stress effects. Testing was carried out with longitudinal attachment welds in the as-welded condition. The initial residual stress was measured by a sectioning method using strain gauges. Hot spot stress was determined experimentally by strain gauges and numerically by finite element analysis using different types of elements. Fatigue testing was carried out and SN-curves were plotted according to the relevant stress as specified by the rules. In order to investigate the shakedown effect of residual stress, testing was performed for several preload conditions, which could be taken to represent maximum load levels in a load history. The aim of the study is to contribute towards a better understanding of the effect of residual stress and shakedown on fatigue strength of welded joints.
The Effect of Boundary Proximity Upon the Wake Structure of Horizontal Axis Marine Current Turbines
Authors: Bahaj A. S. , Myers L. E. , Rawlinson-Smith R. I. , Thomson M.
Published: December 2011

An experimental and theoretical investigation of the flow field around small-scale mesh disk rotor simulators is presented. The downstream wake flow field of the rotor simulators has been observed and measured in the 21m tilting flume at the Chilworth hydraulics laboratory, University of Southampton. The focus of this work is the proximity of flow boundaries (sea bed and surface) to the rotor disks and the constrained nature of the flow. A three-dimensional Eddy-viscosity numerical model based on an established wind turbine wake model has been modified to account for the change in fluid and the presence of a bounding free surface. This work has shown that previous axi-symmetric modeling approaches may not hold for marine current energy technology and a novel approach is required for simulation of the downstream flow field. Such modeling solutions are discussed and resultant simulation results are given. In addition, the presented work has been conducted as part of a UK Government funded project to develop validated numerical modeling tools which can predict the flow onto a marine current turbine within an array. The work feeds into the marine energy program at Southampton to assist developers with layout designs of arrays which are optimally spaced and arranged to achieve the maximum possible energy yield at a given tidal energy site.
Numerical Model for Pipeline Laying During S-lay
Authors: Yuan Feng , Guo Zhen , Li Lingling , Wang Lizhong
Published: December 2011

The S-lay method has been widely used in pipeline installation from shallow water to deep water for decades. In this paper, a novel numerical model for analyzing pipelines in the S-lay problem is proposed to investigate the overall configuration, internal forces, and strain of the pipeline taking into account the influence of ocean currents and seabed stiffness. The influence of many important factors, including the variation position of the liftoff point, the change of stinger radius, ocean currents, seabed stiffness are investigated in detail. Some useful results are obtained: the stress state of the pipeline is found to vary greatly during the whole laying process; the train of the pipeline at both the upper and the lower sides is very important; ocean currents have negligible influence on the pipeline; traditional “touchdown factor” is not suitable to predict the real pipe embedment; and soil stiffness plays an important role in pipeline behavior on the seabed. The illustrative examples and comparison with a previous work demonstrate the widespread applicability of this model. Moreover, the solution process of this model is easy and fast, so it is suitable for engineering applications.
Phase Compensation Strategies for Modulated-Demodulated Control With Application to Pulsed Jet Injection
Authors: Hendrickson Cory , M’Closkey Robert T.
Published: December 2011

Modulated-demodulated control is an effective method for asymptotic disturbance rejection and reference tracking of periodic signals, however, conventional static phase compensation often limits the loop gain in order to avoid sensitivity function peaking in a neighborhood of the frequencies targeted for rejection or tracking. This paper introduces dynamic phase compensation for modulated-demodulated control which improves disturbance rejection characteristics by inverting the plant phase in a neighborhood of the control frequency. Dynamic phase compensation is implemented at baseband which enables the use of low-bandwidth compensators to invert high frequency dynamics. Both static and dynamic phase compensation methods are used to demonstrate a novel application of repetitive control for pulsed jet injection. In this application pulsing an injectant has been shown to produce advantageous effects such as increased mixing in many energy generation and aerospace systems. The sharpness of the pulse can have a large impact on the effectiveness of control. Modulated-demodulated control is used to maximize the sharpness of a pulsed jet of air using active forcing by tracking a square wave in the jet’s temporal velocity profile.
Nonlinear Proportional Plus Integral Control of Optical Traps for Exogenous Force Estimation
Authors: Cole D. G. , Pickel J. G.
Published: December 2011

This article explores nonlinear proportional plus integral (PI) feedback for controlling the position of an object held in an optical trap. In general, nonlinearities in the spatial dependence of the optical force complicate feedback control for optical traps. Nonlinear PI control has been shown to provide all of the benefits of integral control: disturbance rejection, servo tracking, and force estimation. The controller also linearizes the closed-loop system. More importantly, the nonlinear controller is shown to be equivalent to an estimator of the exogenous force. The ability of nonlinear PI control to lower the measurement SNR is evaluated and compared to the variational open-loop case. A simulation demonstrating the performance of the nonlinear PI control is presented.
A Method for Recovering Linear Performance in Feedback Systems With Nonlinear Instrumentation
Authors: Ching ShiNung , Kabamba Pierre T. , Meerkov Semyon M.
Published: December 2011

The problem of controller design in linear systems is well understood. Often, however, when linear controllers are implemented on a physical system, the anticipated performance is not met. In some cases, this can be attributed to nonlinearities in the instrumentation, i.e., sensors and actuators. Intuition suggests that to compensate for this instrumentation, one can boost, i.e., increase, the controller gain. This paper formally pursues this strategy and develops the theory of boosting. It provides conditions under which the controller gain can be modified to offset the effects of instrumentation, thus recovering the performance of the intended linear design. Experimental verification of the technique developed is reported using a magnetic levitation device.
A Hydraulic Circuit for Single Rod Cylinders
Authors: Wang Longke , Book Wayne J. , Huggins James D.
Published: December 2011

This paper proposes a novel hydraulic circuit for a single rod cylinder controlled by a variable displacement pump. The circuit arrangement not only gives the system high energy efficiency but also improves upon the internal instability of traditional circuits. Stability is illustrated by comparing traditional circuits with the proposed circuit. The motivations, derivations, and proofs of the system dynamical stabilities are presented. Control algorithms including stability control and sliding to the desired working region are presented. Experiments are conducted to verify the circuit, and results show that the circuit has good performance.
Effect of Residual Shear Stresses on Released Strains in Isotopic and Orthotropic Materials Measured by the Slitting Method
Authors: Shokrieh Mahmood M. , R. Saeed Akbari
Published: December 2011

This paper investigates the effect of shear stresses on the determination of residual stresses in isotropic and orthotropic materials by the slitting method. A great deal of research effort is focused on the estimation of the residual stress component normal to the slit face using strain data measured by strain gauges installed on the top or the back surface of the stressed specimens. However, the slitting process will also release two in-plane and out-of-plane shear stress components, which may influence the measured strains. For the two specimens of carbon/epoxy and glass/epoxy laminated composites as well as a steel specimen, the distribution of released strains on the top and the back surfaces due to the shear stresses is calculated using finite element method and compared with those due to the residual normal stress. The results show that on the back surface, the shear stresses have a very small effect on the measured strains. However, on the top surface, strains due to the residual shear stresses are significant compared with those due to the residual normal stress and cannot be ignored. A method using two top surface strain gauges in both sides of the slit is presented to separate the effects of normal and shear stresses from each other. Also, strains due to the in-plane and the out-of-plane shear stresses could be isolated from each other. If these separations could be carried out successfully, the residual shear stress can be calculated by the proposed formulation.
A Physiologically Based Pharmacokinetic Model for Capreomycin
Authors: Reisfeld B. , Metzler C. P. , Lyons M. A. , Mayeno A. N. , Brooks E. J. , DeGroote M. A.
Published: December 2011

The emergence of multidrug-resistant tuberculosis (MDR-TB) has led to a renewed interest in the use of second-line antibiotic agents. Unfortunately, there are currently dearths of information, data, and computational models that can be used to help design rational regimens for administration of these drugs. To help fill this knowledge gap, an exploratory physiologically based pharmacokinetic (PBPK) model, supported by targeted experimental data, was developed to predict the absorption, distribution, metabolism, and excretion (ADME) of the second-line agent capreomycin, a cyclic peptide antibiotic often grouped with the aminoglycoside antibiotics. To account for interindividual variability, Bayesian inference and Monte Carlo methods were used for model calibration, validation, and testing. Along with the predictive PBPK model, the first for an antituberculosis agent, this study provides estimates of various key pharmacokinetic parameter distributions and supports a hypothesized mechanism for capreomycin transport into the kidney.
Chemotherapy-Associated Changes of Histopathological Features of Mycobacterium ulcerans Lesions in a Buruli Ulcer Mouse Model
Authors: Ruf Marie-Thérèse , Schütte Daniela , Chauffour Aurélie , Jarlier Vincent , Ji Baohong , Pluschke Gerd
Published: December 2011

Combination chemotherapy with rifampin and streptomycin (RIF-STR) for 8 weeks is currently recommended by the WHO as the first-line treatment for
Mycobacterium ulcerans
infection (Buruli ulcer). To gain better insight into the mode of action of these antibiotics against established
M. ulcerans
infection foci and to characterize recovery of local immune responses during chemotherapy, we conducted a detailed histopathological study of
M. ulcerans
-infected and RIF-STR-treated mice. Mice were inoculated with
M. ulcerans
in the footpad and 11 weeks later treated with RIF-STR. Development of lesions during the first 11 weeks after infection and subsequent differences in disease progression between RIF-STR-treated and untreated mice were studied. Changes in histopathological features, footpad swelling, and number of CFU were analyzed. After inoculation with
M. ulcerans
, massive infiltrates dominated by polymorphonuclear leukocytes developed at the inoculation site but did not prevent bacterial multiplication. Huge clusters of extracellular bacteria located in large necrotic areas and surrounded by dead leukocytes developed in the untreated mice. Chemotherapy with RIF-STR led to a rapid drop in CFU associated with loss of solid Ziehl-Neelsen staining of acid-fast bacilli. Development of B-lymphocyte clusters and of macrophage accumulations surrounding the mycobacteria demonstrated the resolution of local immune suppression. Results demonstrate that the experimental
M. ulcerans
mouse infection model will be a valuable tool to investigate efficacy of new treatment regimens and of candidate vaccines.
Live Attenuated Salmonella Vaccines against Mycobacterium tuberculosis with Antigen Delivery via the Type III Secretion System
Authors: Juárez-Rodríguez María Dolores , Arteaga-Cortés Lourdes T. , Kader Rebin , Curtiss Roy , Clark-Curtiss Josephine E.
Published: December 2011

Tuberculosis remains a global health threat, and there is dire need to develop a vaccine that is safe and efficacious and confers long-lasting protection. In this study, we constructed recombinant attenuatedSalmonellavaccine (RASV) strains with plasmids expressing fusion proteins consisting of the 80 amino-terminal amino acids of the type 3 secretion system effector SopE ofSalmonellaand theMycobacterium tuberculosisantigens early secreted antigenic target 6-kDa (ESAT-6) protein and culture filtrate protein 10 (CFP-10). We demonstrated that the SopE-mycobacterial antigen fusion proteins were translocated into the cytoplasm of INT-407 cells in cell culture assays. Oral immunization of mice with RASV strains synthesizing SopE–ESAT-6–CFP-10 fusion proteins resulted in significant protection of the mice against aerosol challenge withM. tuberculosisH37Rv that was similar to the protection afforded by immunization withMycobacterium bovisbacillus Calmette-Guérin (BCG) administered subcutaneously. In addition, oral immunization with the RASV strains specifying these mycobacterial antigens elicited production of significant antibody titers to ESAT-6 and production of ESAT-6- or CFP-10-specific gamma interferon (IFN-γ)-secreting and tumor necrosis factor alpha (TNF-α)-secreting splenocytes.
Bacillus subtilis-Mediated Protection from Citrobacter rodentium-Associated Enteric Disease RequiresespHand Functional Flagella
Authors: Jones Sara E. , Knight Katherine L.
Published: December 2011

Commensals limit disease caused by invading pathogens; however, the mechanisms and genes utilized by beneficial microbes to inhibit pathogenesis are poorly understood. The attaching and effacing mouse pathogenCitrobacter rodentiumassociates intimately with the intestinal epithelium, and infections result in acute colitis.C. rodentiumis used to model the human pathogens enterohemorrhagicEscherichia coliand enteropathogenicE. coli. To confirm thatBacillus subtilis, a spore-forming bacterium found in the gut of mammals, could reduceC. rodentium-associated disease, mice received wild-typeB. subtilisspores and 24 h later were infected by oral gavage with pathogenicC. rodentium. Disease was assessed by determining the extent of colonic epithelial hyperplasia, goblet cell loss, diarrhea, and pathogen colonization. Mice that received wild-typeB. subtilisprior to enteric infection were protected from disease even thoughC. rodentiumcolonization was not inhibited. In contrast,espHandhagmutants, defective in exopolysaccharides and flagellum production, respectively, did not protect mice fromC. rodentium-associated disease. AmotABmutant also failed to protect mice from disease, suggesting thatB. subtilis-mediated protection requires functional flagella. By expanding our current mechanistic knowledge of bacterial protection, we can better utilize beneficial microbes to prevent intestinal disease caused by pathogenic bacteria, ultimately reducing human disease. Our data demonstrate that wild-typeB. subtilisreduced disease caused byC. rodentiuminfection through a mechanism that requiredespHand functional flagella.
Enterohemorrhagic Escherichia coli Virulence Regulation by Two Bacterial Adrenergic Kinases, QseC and QseE
Authors: Njoroge Jacqueline , Sperandio Vanessa
Published: December 2011

The human pathogen enterohemorrhagic
Escherichia coli
(EHEC) O157:H7 has two histidine sensor kinases, QseC and QseE, which respond to the mammalian adrenergic hormones epinephrine and norepinephrine by increasing their autophosphorylation. Although QseC and QseE are present in nonpathogenic strains of
E. coli
, EHEC exploits these kinases for virulence regulation. To further investigate the full extent of epinephrine and its sensors' impact on EHEC virulence, we performed transcriptomic and phenotypic analyses of single and double deletions of
qseC
and
qseE
genes in the absence or presence of epinephrine. We showed that in EHEC, epinephrine sensing seems to occur primarily through QseC and QseE. We also observed that QseC and QseE regulate expression of the locus of enterocyte effacement (LEE) genes positively and negatively, respectively. LEE activation, which is required for the formation of the characteristic attaching and effacing (A/E) lesions by EHEC on epithelial cells, is epinephrine dependent. Regulation of the LEE and the non-LEE-contained virulence factor gene
nleA
by QseE is indirect, through transcription inhibition of the RcsB response regulator. Finally, we show that coincubation of HeLa cells with epinephrine increases EHEC infectivity in a QseC- and QseE-dependent manner. These results genetically and phenotypically map the contributions of the two adrenergic sensors QseC and QseE to EHEC pathogenesis.
Precompetition medical assessment of referees and assistant referees selected for the 2010 FIFA World Cup: Table 1
Authors: Bizzini Mario , Schmied Christian , Junge Astrid , Dvorak Jiri
Published: December 2011

Background

Several proposals for preparticipation screening to detect risk factors for sudden cardiac death in sports have been published, but referees have been neglected in this respect.

Methods

A standardised precompetition medical assessment (comprising a general physical, orthopaedic and cardiac examination and blood analysis) was performed in all 90 referees and assistant referees selected for the 2010 Fédération Internationale de Football Association World Cup.

Results

More than a third of the referees showed at least one pathological finding in cardiac examinations; however, all follow-up examinations proved to be normal. The relatively high prevalence of pathological findings in the blood analysis and the orthopaedic examination can be attributed to the average age of the referees and none of them was performance limiting.

Conclusions

Considering their risk of occult ischaemic heart disease, a precompetition medical assessment including an exercise ECG is recommended in elite male football referees.
The sports concussion note: should SCAT become SCOAT?: Table 1
Authors: Patricios Jon , Collins Robert , Branfield Andrew , Roberts Craig , Kohler Ryan
Published: December 2011

Sports concussion research and clinical guidelines have evolved rapidly. The most recent concussion consensus statement and guidelines (Zurich, 2008) provided clinicians with the Sports Concussion Assessment Tool version 2 (SCAT2) as a clinical template for the assessment of acute concussion. For the subsequent serial examinations required for the complete assessment of the concussed athlete, SCAT2 may be inadequate. This paper describes the experience and suggestions of South African sports physicians in evolving a more comprehensive clinical evaluation tool and record of patient care, the Sports Concussion Office Assessment Tool.
VARIETIES OF REPRESENTATIONS OF GROUPS AND VARIETIES OF ASSOCIATIVE ALGEBRAS
Authors: ALADOVA ELENA , PLOTKIN BORIS
Published: December 2011

This paper is tightly connected with the book [Varieties of Group Representations. General Theory, Connections and Applications (Zinatne, Riga, 1983) (in Russian)]. In the paper we prove new results in the spirit of the above-mentioned book. They are related to dimension subgroups, varieties of representations of groups and varieties of associative algebras. The main emphasis is put on the varieties of representations of groups induced by the varieties of associative algebras. We provide the reader with the list of open problems. For many reasons we consciously included in the text a brief review of the basic definitions and results from the theory of varieties of representations described in the book [Varieties of Group Representations. General Theory, Connections and Applications].
GRAVITATIONAL LENSING IN AN ENERGY-DEPENDENT SPACETIME METRIC
Authors: GRILLO A. F. , LUZIO E. , MÉNDEZ F. , TORRES F.
Published: December 2011

In this article, we explore the consequences in the calculation of deflection angle of photons, caused by a gravitational source of mass M, for the case of an energy dependent metric. We analyze the corrections to the standard Schwarzschild case for the weak and strong limits. In both cases, the corrections to the deflection angle are of the order ϵ/E Pl , where E Pl is the Planck energy and ϵ, the energy of the photon at spatial infinite. The corrections to the angular separation image is also of order ϵ/E Pl , for the weak limit, while in the strong case there is a corrective term with the shape ϵ/E Pl n e2nπ for the relativistic image of order n. The amplification of the image is also discussed. Even if corrections are tiny, in both limits, we discuss the qualitative effects for different types of Lorentz invariance deformations.
A SECURE REVERSION PROTOCOL THAT GENERATES PAY-OFFS DOMINATING REWARDS FROM CORRELATED EQUILIBRIUM
Authors: WANKO CEDRIC
Published: December 2011

We define the reversion protocol of a voluntarily implementable Bayesian mechanism in which risk-averse players have no incentive to cheat or to deviate from the mediator's recommendation and that can greatly improve their equilibrium expected pay-offs as compared to those generated through coordination applied to the results of an unsatisfactory mediation.
THE DYNAMICS OF INTERNET TRAFFIC: SELF-SIMILARITY, SELF-ORGANIZATION, AND COMPLEX PHENOMENA
Authors: SMITH REGINALD D.
Published: December 2011

The Internet is one of the largest and most complex communication and information exchange networks ever created. Therefore, its dynamics and traffic unsurprisingly take on a rich variety of complex dynamics, self-organization, and other phenomena that have been researched for years. This paper is a review of the complex dynamics of Internet traffic. Departing from normal treatises, we will take a view from both the network engineering and physics perspectives showing the strengths and weaknesses as well as insights of both. In addition, many less covered phenomena such as traffic oscillations, BGP storms, and comparisons of the Internet and biological models will be covered.
NEURAL SYSTEM MODELING AND SIMULATION USING HYBRID FUNCTIONAL PETRI NET
Authors: TANG YIN , WANG FEI
Published: December 2011

The Petri net formalism has been proved to be powerful in biological modeling. It not only boasts of a most intuitive graphical presentation but also combines the methods of classical systems biology with the discrete modeling technique. Hybrid Functional Petri Net (HFPN) was proposed specially for biological system modeling. An array of well-constructed biological models using HFPN yielded very interesting results. In this paper, we propose a method to represent neural system behavior, where biochemistry and electrical chemistry are both included using the Petri net formalism. We built a model for the adrenergic system using HFPN and employed quantitative analysis. Our simulation results match the biological data well, showing that the model is very effective. Predictions made on our model further manifest the modeling power of HFPN and improve the understanding of the adrenergic system. The file of our model and more results with their analysis are available in our supplementary material.
ONLINE CHANNELS AND INNOVATION: ARE USERS BEING EMPOWERED AND INVOLVED?
Authors: JESPERSEN KRISTINA RISOM
Published: December 2011

Innovation literature points directly to the Internet and the various form of online channels that companies can implemented as part of user involvement and empowerment in innovation. Yet implementing open innovation requires that online channels lead to user involvement. Online channels can be used for different purposes and will not by themselves create open innovation. This paper therefore analyzes the capability of companies to implement open innovation through use of online channels. The results show that there is a fine line between user involvement and customer orientation. Online channels do not necessarily empower users in the innovation process. In addition, the paper find that on B2C markets pioneering users hold an unrealized innovative potential that could benefit the diffusion of open innovation in these markets.
OPEN INNOVATION MATURITY FRAMEWORK
Authors: ENKEL ELLEN , BELL JOHN , HOGENKAMP HANNAH
Published: December 2011

Open innovation can introduce new ways of organizing the innovation process within companies, but these new activities and processes naturally require some time to mature and work effectively. Continuous improvement of capacities and results is therefore required (Teece et al., 1997; Winter, 2003). The basic aim of this research was to develop, in collaboration with 15 companies, an open innovation maturity framework to measure and benchmark excellence in open innovation. The open innovation maturity framework that was developed combines metrics in several areas of open innovation to illustrate the expertise of that organization. It can reveal organizational excellence as well as areas of improvement in order to reach the next level of maturity.
IMPACT OF PUBLIC FUNDING ON A FIRM'S INNOVATION PERFORMANCE: ANALYSIS OF INTERNAL AND EXTERNAL MODERATING FACTORS
Authors: ALBORS-GARRIGOS JOSE , BARRERA ROSA RODRIGUEZ
Published: December 2011

This paper analyses the effect of public subsidies on a firm's innovation performance. The research aims at filling two research gaps. First, it will try to analyse the effect of public source funding directly on a firm's innovation performance analysing not the effects on R&D investment or intensity but on the final results of the innovative effort, its outcome. Secondly, it will examine the mediating effects of various (internal and external to the firm innovative behaviour) factors which influence the whole innovation process and, though have been identified by literature, its effects have not yet been properly quantified.
NEW BUSINESS MODELS THROUGH COLLABORATIVE IDEA GENERATION
Authors: EPPLER MARTIN J. , HOFFMANN FRIEDERIKE , BRESCIANI SABRINA
Published: December 2011

Generating novel and sustainable business model ideas is a crucial yet challenging innovation task. A growing body of literature shows that artefacts, such as visual templates, objects and sketches, can enhance team collaboration and creativity in innovation activities. Drawing on literature from diverse fields we propose a model that aims to explain how artefacts can affect the team processes in developing new business model ideas, positing that they have an impact on creativity and collaboration. We report the results of an illustrative experimental study comparing the team processes of managers working on a business model innovation task. Teams were supported by different types of artefacts (a business model template; physical objects with sketching; or PowerPoint). The results indicate that using the template significantly increases perceived collaboration and decreases perceived creativity, hence showing that artefacts can have the power to shape team work for innovation tasks.
Sequencing the graptoloid clade: building a global diversity curve from local range charts, regional composites and global time-lines
Authors: Sadler Peter M. , Cooper Roger A. , Melchin Michael J.
Published: December 2011

Even range charts from the best graptoloid-bearing sections can be improved by adding information from nearby sections. Traditionally this is achieved on a scale of discrete biozones. Zonal composites improve upon the taxon richness of individual sections but lose resolving power; they artificially cluster range-end events at zone boundaries. Graphical and numerical methods allow composite sections to be constructed on continuous scales that match or exceed the resolving power of individual sections. Using a database of 582 graptoloid-bearing sections that together preserve 2214 distinct graptoloid taxa, we show that constrained optimization algorithms can construct objective, reproducible, global time-lines for the entire Ordovician to early Devonian graptoloid clade. The underlying database of locally observed ranges allows standardization for sampling unevenness. The quality and geographic origins of support for composite taxon ranges are explicitly revealed. A high precision, interval-free, standing species richness curve derived by this approach reveals the diversity trajectory of the graptoloid clade and of the families of which it is composed. Major reorganizations of the clade at the family level took place after diversity minima in the late Darriwilian and Hirnantian. Glacial events recognized on sedimentological evidence coincide with diversity minima.
Ranking function adaptation with boosting trees
Authors: Chen Keke , Bai Jing , Zheng Zhaohui
Published: December 2011

Machine-learned ranking functions have shown successes in Web search engines. With the increasing demands on developing effective ranking functions for different search domains, we have seen a big bottleneck, that is, the problem of insufficient labeled training data, which has significantly slowed the development and deployment of machine-learned ranking functions for different domains. There are two possible approaches to address this problem: (1) combining labeled training data from similar domains with the small target-domain labeled data for training or (2) using pairwise preference data extracted from user clickthrough log for the target domain for training. In this article, we propose a new approach called tree-based ranking function adaptation (Trada) to effectively utilize these data sources for training cross-domain ranking functions. Tree adaptation assumes that ranking functions are trained with the Stochastic Gradient Boosting Trees method—a gradient boosting method on regression trees. It takes such a ranking function from one domain and tunes its tree-based structure with a small amount of training data from the target domain. The unique features include (1) automatic identification of the part of the model that needs adjustment for the new domain and (2) appropriate weighing of training examples considering both local and global distributions. Based on a novel pairwise loss function that we developed for pairwise learning, the basic tree adaptation algorithm is also extended (Pairwise Trada) to utilize the pairwise preference data from the target domain to further improve the effectiveness of adaptation. Experiments are performed on real datasets to show that tree adaptation can provide better-quality ranking functions for a new domain than other methods.
Recommendation systems with complex constraints
Authors: Parameswaran Aditya , Venetis Petros , Garcia-Molina Hector
Published: December 2011

We study the problem of making recommendations when the objects to be recommended must also satisfy constraints or requirements. In particular, we focus on course recommendations: the courses taken by a student must satisfy requirements (e.g., take two out of a set of five math courses) in order for the student to graduate. Our work is done in the context of the CourseRank system, used by students to plan their academic program at Stanford University. Our goal is to recommend to these students courses that not only help satisfy constraints, but that are also desirable (e.g., popular or taken by similar students). We develop increasingly expressive models for course requirements, and present a variety of schemes for both checking if the requirements are satisfied, and for making recommendations that take into account the requirements. We show that some types of requirements are inherently expensive to check, and we present exact, as well as heuristic techniques, for those cases. Although our work is specific to course requirements, it provides insights into the design of recommendation systems in the presence of complex constraints found in other applications.
Attentional gradient for crossmodal proximal-distal tactile cueing of visual spatial attention
Authors: Rosli Roslizawaty Mohd , Tan Hong Z. , Proctor Robert W. , Gray Rob
Published: December 2011

Past studies have established a crossmodal spatial attentional link among vision, audition, and touch. The present study examined the dependence of visual attention on the distance between a distal visual target (a changing element among static distractors) and the quadrant of the visual display cued by a proximal tactile stimulus. The distance between the center of the cued visual quadrant and the visual target was one of six values: 0, 90, 180, 350, 450, and 550 pixels. The distances of 0, 90, and 180 corresponded to the valid tactile cueing condition, where the tactile cue and the visual target occurred in the same quadrant. The distances of 350, 450, and 550 corresponded to the invalid tactile cueing condition, where the tactilely-cued quadrant did not match that of the visual change. Results from 10 young adults showed that mean response time increased with respect to the cue-target distance, thereby confirming a gradient of visual attention for proximal-distal tactile cueing. In addition, the response times for valid tactile cues were shorter than those for invalid tactile cues, confirming earlier findings that valid tactile cues facilitate visual search and invalid tactile cues interfere with visual search. The findings of the present study have implications for the design of multimodal attention-cueing systems for practical applications such as collision warning systems in automobiles.
Effects of scale change on distance perception in virtual environments
Authors: Nguyen Tien Dat , Ziemer Christine J. , Grechkin Timofey , Chihak Benjamin , Plumert Jodie M. , Cremer James F. , Kearney Joseph K.
Published: December 2011

We conducted a series of experiments to investigate effects of scale changes on distance perception in virtual environments. All experiments were carried out in an HMD. Participants first made distance estimates with feedback in a virtual tunnel (adaptation) and then made distance estimates without feedback in a differently-scaled virtual environment (test). We examined several types of scale changes, including changing the size of (1) the tunnel, (2) the targets, and (3) the separation of the two targets. Changes in target size always affected distance estimates at test. When the targets became smaller, participants overshot distance and when the targets became larger, participants undershot distance. Changes in the size of the tunnel or the separation between the targets (without a change in the size of the targets) had a minimal effect on distance estimates. These results indicate that distance estimates at test were strongly influenced by familiar size cues for distance. The discussion focuses on the stability of calibration processes and mechanisms for cue integration for perceiving distance in virtual environments.