bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Brachial-Ankle Pulse Wave Velocity Is Independently Associated with White Matter Hyperintensities
Authors: Saji Naoki , Shimizu Hirotaka , Kawarai Toshitaka , Tadano Makoto , Kita Yasushi , Yokono Koichi
Published: June 2011

Background: White matter hyperintensities (WMHs) are a risk factor for stroke. Their etiology is considered to be cerebral microvascular abnormality. However, the association between WMHs and arteriosclerosis is not yet clear. The aim of this hospital-based cohort study was to identify the arteriosclerotic characteristics associated with WMHs. Methods: We cross-sectionally included 240 consecutive patients with no history of stroke. We measured the brachial-ankle pulse wave velocity (baPWV), ankle brachial pressure index, and intima-media thickness of the common carotid artery, and we performed magnetic resonance brain imaging. WMHs were defined as periventricular hyperintensity (Fazekas grade ≧3) and/or separate deep white matter hyperintense signals (Fazekas grade ≧2). We determined the prevalence of WMHs, silent brain infarction (SBI), hypertension, hypercholesterolemia, diabetes mellitus, ischemic heart disease, and smoking. We compared 2 groups of patients, defined by the presence or absence of WMHs, using multiple logistic regression analyses. Results: In multivariable analysis, SBI (OR 3.38; 95% CI 1.52–7.72), hypertension (OR 2.23; 95% CI 1.03–5.15), female sex (OR 1.95; 95% CI 1.03–3.76), baPWV (OR 1.12; 95% CI 1.02–1.23), and age (OR 1.09; 95% CI 1.04–1.14) were independently associated with WMHs. Conclusions: An increased baPWV is associated with WMHs. Management of increased baPWV may help to prevent the progression of WMHs and stroke.
Altered Phenotype of Blood Dendritic Cells in Patients with Acute Pneumonia
Authors: Dreschler Katharina , Bratke Kai , Petermann Sebastian , Thamm Petra , Kuepper Michael , Virchow J. Christian , Lommatzsch Marek
Published: June 2011

Background: Dendritic cells (DCs) play a key role in the host defence against inhaled pathogens. However, the phenotype of blood DCs in patients with acute respiratory infections is unknown. Objective: To investigate the number and the expression of function-associated molecules of blood DCs in patients with acute infectious pneumonia. Methods: Sixteen patients with acute pneumonia and 19 controls without pneumonia were included in the study. The number as well as the expression of function-associated molecules of myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) were analysed in peripheral blood using four-colour flow cytometry. Results: Elevated concentrations of procalcitonin (median: 0.55 ng/ml) and the rapid response to antibiotic treatment suggested a bacterial origin of the pneumonia in the patients. Total mDC (median: 27% of the controls) and pDC counts (median: 53% of the controls) were markedly reduced in patients with pneumonia, as compared to the controls. Percentages of blood mDCs, but not pDCs, were negatively correlated with serum concentrations of C-reactive protein. Patients with pneumonia were characterised by a significantly increased expression of Fc gamma receptors (CD32 and CD64) on mDCs and the Toll-like receptor 9 (TLR9) on pDCs. Conclusions: Circulating DCs are markedly reduced in patients with pneumonia, and characterised by an up-regulation of molecules recognising pathogen-associated molecular patterns and opsonised antigens.
Predicting Hospital Mortality in Critically Ill Cancer Patients according to Acute Kidney Injury Severity
Authors: Libório Alexandre Braga , Abreu Krasnalhia Lívia S. , Silva, Jr. Geraldo B. , Lima Rafael S.A. , Barreto Adller G.C. , Barbosa Orivaldo A. , Daher Elizabeth F.
Published: June 2011

Background: Acute kidney injury (AKI) is a frequent complication in hospitalized patients, especially in those in intensive care units (ICU). The RIFLE classification might be a valid prognostic factor for critically ill cancer patients. The present study aims to evaluate the discriminatory capacity of RIFLE versus other general prognostic scores in predicting hospital mortality in critically ill cancer patients. Methods: This is a single-center study conducted in a cancer-specialized ICU in Brazil. All of the 288 patients hospitalized from May 2006 to June 2008 were included. RIFLE classification, APACHE II, SOFA, and SAPS II scores were calculated and the area under receiver operating characteristic (AROC) curves and logistic multiple regression were performed using hospital mortality as the outcome. Results: AKI, defined by RIFLE criteria, was observed in 156 (54.2%) patients. The distribution of patients with any degree of AKI was: risk, n = 96 (33.3%); injury, n = 30 (10.4%), and failure, n = 30 (10.4%). Mortality was 13.6% for non-AKI patients, 49% for RIFLE ‘R’ patients, 62.3% for RIFLE ‘I’ patients, and 86.8% for RIFLE ‘F’ patients (p = 0.0006). Logistic regression analysis showed that RIFLE criteria, APACHE II, SOFA, and SAPS II were independent factors for mortality in this population. The discrimination of RIFLE was good (AROC 0.801, 95% CI 0.748–0.854) but inferior compared to those of APACHE II (AROC 0.940, 95% CI 0.915–0.966), SOFA (AROC 0.910, 95% CI 0.876–0.943), and SAPS II (AROC 0.869, 95% CI 0.827–0.912). Conclusion: AKI is a frequent complication in ICU patients with cancer. RIFLE was inferior to commonly used prognostic scores for predicting mortality in this cohort of patients.
Monocyte and Macrophage Dynamics During Atherogenesis
Authors: Ley Klaus , Miller Yury I. , Hedrick Catherine C.
Published: June 2011

Vascular inflammation is associated with and in large part driven by changes in the leukocyte compartment of the vessel wall. Here, we focus on monocyte influx during atherosclerosis, the most common form of vascular inflammation. Although the arterial wall contains a large number of resident macrophages and some resident dendritic cells, atherosclerosis drives a rapid influx of inflammatory monocytes (Ly-6C
+
in mice) and other monocytes (Ly-6C
−
in mice, also known as patrolling monocytes). Once in the vessel wall, Ly-6C
+
monocytes differentiate to a phenotype consistent with inflammatory macrophages and inflammatory dendritic cells. The phenotype of these cells is modulated by lipid uptake, Toll-like receptor ligands, hematopoietic growth factors, cytokines, and chemokines. In addition to newly recruited macrophages, it is likely that resident macrophages also change their phenotype. Monocyte-derived inflammatory macrophages have a short half-life. After undergoing apoptosis, they may be taken up by surrounding macrophages or, if the phagocytic capacity is overwhelmed, can undergo secondary necrosis, a key event in forming the necrotic core of atherosclerotic lesions. In this review, we discuss these and other processes associated with monocytic cell dynamics in the vascular wall and their role in the initiation and progression of atherosclerosis.
Surgical Ablation of Refractory Ventricular Tachycardia in Patients With Nonischemic Cardiomyopathy
Authors: Anter Elad , Hutchinson Mathew D. , Deo Rajat , Haqqani Haris M. , Callans David J. , Gerstenfeld Edward P. , Garcia Fermin C. , Bala Rupa , Lin David , Riley Michael P. , Litt Harold I. , Woo Joseph Y. , Acker Michael A. , Szeto Wilson Y. , Zado Erica S. , Marchlinski Francis E. , Dixit Sanjay
Published: June 2011

Background—

The surgical approach for the treatment of ventricular tachycardia (VT) has been largely replaced by percutaneous, catheter-based techniques. However, some VT circuits, particularly in patients with nonischemic cardiomyopathy, remain inaccessible to percutaneous ablation. Surgical therapy of these VTs is an alternative approach; however, its methodology has not been well defined. The purpose of this study was to evaluate the efficacy of preoperative electroanatomic and electrophysiological characterization of the VT substrate and circuit to guide surgical ablation.

Methods and Results—

Eight patients with recurrent sustained VT refractory to antiarrhythmic drugs underwent endocardial and/or epicardial ablation procedures. Electroanatomic mapping was performed, and the VT substrate and circuit(s) were defined using voltage, activation, entrainment, and pace mapping. All 8 patients underwent detailed endocardial mapping; 6 patients also underwent epicardial mapping. Radiofrequency ablation was performed with the use of an open-irrigation catheter. After the unsuccessful percutaneous approach, surgical cryoablation was applied to the sites previously identified and targeted during the percutaneous procedure. There were no significant perioperative complications. During a mean follow-up period of 23±6 months (range, 15 to 34 months), 6 patients had significant reduction in VT burden as evident by a reduced number of implantable cardioverter-defibrillator shocks after ablation (6.6 to 0.6 shocks per patient;
P
=0.026). Two patients died, one of progressive heart failure and one of sepsis.

Conclusions—

VT circuits inaccessible to percutaneous ablation techniques are rare but can be encountered in patients with nonischemic cardiomyopathy. These VTs can be successfully targeted by surgical cryoablation guided by preoperative electroanatomic and electrophysiological mapping.
Impact of Change in Serum Sodium Concentration on Mortality in Patients Hospitalized With Heart Failure and Hyponatremia
Authors: Madan Vinay D. , Novak Eric , Rich Michael W.
Published: June 2011

Background—

Hyponatremia is a common electrolyte abnormality among patients hospitalized with heart failure and it is a marker for increased short-term and long-term mortality. However, little is known about the time course of hyponatremia and whether changes in serum sodium levels affect clinical outcomes.

Methods and Results—

Patients (n=322) hospitalized with decompensated heart failure and serum sodium <135 mmol/L were evaluated. After hospital discharge, the first sodium value obtained within a 60- to 270-day period was recorded, and patients were classified into 3 groups, based on whether the serum sodium value increased (≥2 mmol/L), decreased (≤2 mmol/L), or remained unchanged (±1 mmol/L) relative to the baseline value. Kaplan–Meier survival curves were constructed to illustrate mortality as a function of change in sodium concentration over time, and a Cox-proportional hazards model was constructed to determine if change in serum sodium concentration predicted mortality after adjusting for relevant covariates. The mean age of the population was 66 years, 45% were women, and 55% were white. The mean baseline sodium level was 131 mmol/L and the mean ejection fraction was 32.5%. Two hundred twenty-two patients (68.9%) exhibited an increase in sodium during follow-up; in 57 patients (17.7%) the level was unchanged and in 43 patients (13.4%) there was a decrease in sodium level. During a median follow-up of 610 days, there was a strong positive association between change in sodium level and survival (
P
for trend <0.001); that is, increased sodium was associated with decreased mortality. In multivariable analysis, change in sodium concentration and higher blood urea nitrogen were the strongest predictors of mortality (both
P
<0.0001).

Conclusions—

Among patients hospitalized with heart failure and hyponatremia, change in serum sodium concentration over time is a strong predictor of long-term survival.
Study–Test Congruency Affects Encoding-related Brain Activity for Some but Not All Stimulus Materials
Authors: Bauch Eva M. , Otten Leun J.
Published: June 2011

Memory improves when encoding and retrieval processes overlap. Here, we investigated how the neural bases of long-term memory encoding vary as a function of the degree to which functional processes engaged at study are engaged again at test. In an incidental learning paradigm, electrical brain activity was recorded from the scalps of healthy adults while they made size judgments on intermixed series of pictures and words. After a 1-hr delay, memory for the items was tested with a recognition task incorporating remember/know judgments. In different groups of participants, studied items were either probed in the same mode of presentation (word–word; picture–picture) or in the alternative mode of presentation (word–picture; picture–word). Activity over anterior scalp sites predicted later memory of words, irrespective of type of test probe. Encoding-related activity for pictures, by contrast, differed qualitatively depending on how an item was cued at test. When a picture was probed with a picture, activity over anterior scalp sites predicted encoding success. When a picture was probed with a word, encoding-related activity was instead maximal over posterior sites. Activity differed according to study–test congruency from around 100 msec after picture onset. These findings indicate that electrophysiological correlates of encoding are sensitive to the similarity between processes engaged at study and test. The time course supports a direct and not merely consequential role of encoding–retrieval overlap in encoding. However, because congruency only affected one type of stimulus material, encoding–retrieval overlap may not be a universal organizing principle of neural correlates of memory.
A Differential Model of the Complex Cell
Authors: Hansard Miles , Horaud Radu
Published: June 2011

The receptive fields of simple cells in the visual cortex can be understood as linear filters. These filters can be modeled by Gabor functions or gaussian derivatives. Gabor functions can also be combined in an energy model of the complex cell response. This letter proposes an alternative model of the complex cell, based on gaussian derivatives. It is most important to account for the insensitivity of the complex response to small shifts of the image. The new model uses a linear combination of the first few derivative filters, at a single position, to approximate the first derivative filter, at a series of adjacent positions. The maximum response, over all positions, gives a signal that is insensitive to small shifts of the image. This model, unlike previous approaches, is based on the scale space theory of visual processing. In particular, the complex cell is built from filters that respond to the 2D differential structure of the image. The computational aspects of the new model are studied in one and two dimensions, using the steerability of the gaussian derivatives. The response of the model to basic images, such as edges and gratings, is derived formally. The response to natural images is also evaluated, using statistical measures of shift insensitivity. The neural implementation and predictions of the model are discussed.
Algorithms for Nonnegative Matrix Factorization with the β-Divergence
Authors: Févotte Cédric , Idier Jérôme
Published: June 2011

This letter describes algorithms for nonnegative matrix factorization (NMF) with the β-divergence (β-NMF). The β-divergence is a family of cost functions parameterized by a single shape parameter β that takes the Euclidean distance, the Kullback-Leibler divergence, and the Itakura-Saito divergence as special cases (β = 2, 1, 0 respectively). The proposed algorithms are based on a surrogate auxiliary function (a local majorization of the criterion function). We first describe a majorization-minimization algorithm that leads to multiplicative updates, which differ from standard heuristic multiplicative updates by a β-dependent power exponent. The monotonicity of the heuristic algorithm can, however, be proven for β ∈ (0, 1) using the proposed auxiliary function. Then we introduce the concept of the majorization-equalization (ME) algorithm, which produces updates that move along constant level sets of the auxiliary function and lead to larger steps than MM. Simulations on synthetic and real data illustrate the faster convergence of the ME approach. The letter also describes how the proposed algorithms can be adapted to two common variants of NMF: penalized NMF (when a penalty function of the factors is added to the criterion function) and convex NMF (when the dictionary is assumed to belong to a known subspace).
Finding the Event Structure of Neuronal Spike Trains
Authors: Toups J. Vincent , Fellous Jean-Marc , Thomas Peter J. , Sejnowski Terrence J. , Tiesinga Paul H.
Published: June 2011

Neurons in sensory systems convey information about physical stimuli in their spike trains. In vitro, single neurons respond precisely and reliably to the repeated injection of the same fluctuating current, producing regions of elevated firing rate, termed events. Analysis of these spike trains reveals that multiple distinct spike patterns can be identified as trial-to-trial correlations between spike times (Fellous, Tiesinga, Thomas, & Sejnowski, 2004 ). Finding events in data with realistic spiking statistics is challenging because events belonging to different spike patterns may overlap. We propose a method for finding spiking events that uses contextual information to disambiguate which pattern a trial belongs to. The procedure can be applied to spike trains of the same neuron across multiple trials to detect and separate responses obtained during different brain states. The procedure can also be applied to spike trains from multiple simultaneously recorded neurons in order to identify volleys of near-synchronous activity or to distinguish between excitatory and inhibitory neurons. The procedure was tested using artificial data as well as recordings in vitro in response to fluctuating current waveforms.
Poverty in China’s Urban Communities
Authors: Cheng Zhiming
Published: June 2011

In China’s transition to a market economy, the old socialist system which included full employment and comprehensive social welfare for urban citizens has been replaced by an emerging labour market and a rebuilt social security. The collapse of the old system has thrown a large number of retrenched state workers into poverty and then concentrated the poor in particular communities. This study specifically addresses urban poverty in the state-enterprise residential areas and private housing areas of two cities in northeastern and southwestern China. The two-step study firstly profiles the poverty and characteristics from city to individual level and then identifies the main determinants of poverty in the early 2000s. Urban low-income households had suffered multidimensional disadvantages due to a number of factors including increasing inequality, industrial reconstruction, legacies of the socialist system and the policy and financial burdens of their (previous) affiliated danwei (work units). Data analysis also show that for individual household, employment status, position of the household head and the sector the household head worked in were important to overcome poverty. The emerging poverty in urban communities indicates that a substantial part of residents did not benefit much from development. Moreover, degradation of these communities increases the risk of becoming slums and further marginalization.
The Long Years of China’s South Asia Policy
Authors: Deshpande G.P.
Published: June 2011

The concept of ‘national interests’ does not quite explain the various volte faces that communist China has made over its history, nor its concern with the global distribution of power. The Chinese seem to believe that there are no permanent (national) interests, and whether someone is a friend or enemy is decided by the world order and China’s or any other power’s role in and relationship with it. For China, order in itself is neither desirable nor undesirable but it is an adversarial world or domestic order that decides and forces Chinese response. This does not always mean an antagonistic or irreconcilable contradiction. Indeed, with a few exceptions, Chinese foreign policy has almost always tried to eschew confrontation. China’s identity as a permanent member of the UN Security Council since 1971 and as one of the five acknowledged nuclear powers has, however, meant that it has sought increasingly to take on a system-management role in the world. This in turn may not necessarily lead to the best of times between China and South Asia and, in particular, between China and India.
China and India in the Indian Ocean Region
Authors: Bhaskar C. Uday
Published: June 2011

China and India have divergent political ideologies, characteristics, aspirations, anxieties, and hence their strategic perceptions and orientations differ. Their strategic interaction in southern Asia has for its backdrop the 1962 border conflict. In terms of maritime security, the Pacific–Indian Ocean continuum has become the centre of gravity post-9/11 with both China and India having long-term growth trajectories in terms of naval power, a process skewed in favour of the PLA Navy (PLAN). Cognisance of the maritime dependency index for energy and anxieties about secure sea-lines of communication (SLOC) by China and India give rise to a ‘Malacca dilemma’ and a ‘Hormuz dilemma’ respectively. The firm belief at the politico-military apex that Beijing’s future strategic profile and relevance is inexorably linked with its naval capability gives the PLAN a steadily increasing footprint in the Indian Ocean Region (IOR). Active political engagements and long-term port investments in the IOR by Beijing, though presented as benign, trigger concerns in India. These equations are influenced by a three-tiered strategic subalternity in Asia between the US (and its allies), China and India. The manner in which contested territoriality between the Asian neighbours will be resolved is the key on which future outcomes depend. While this may point towards China acquiring a military edge in the IOR, for India prudence, restraint and capacity-building remain vital.
Dentin Regeneration in vitro
Authors: About I.
Published: June 2011

The elaboration of dentin-pulp engineering strategies requires the investigation of not only progenitor cell potentials but also their interactions with other non-progenitor “supportive” cells. Under severe caries lesions, progenitor cells may be activated by growth factors released after the acidic dissolution of carious dentin. However, dentin regeneration has also been observed after traumatic injuries without any significant dentin dissolution. This raises questions about the origin of signals involved in progenitor cell activation, migration, and differentiation. Study models such as the entire tooth culture and co-cultures of pulp and endothelial cells highlighted the role of interactions between the different pulp cell types and the pivotal role they play in dentin regeneration. Injured pulp fibroblasts secrete growth factors involved in progenitor cell activation and differentiation as well as neoangiogenesis which may pave the pathways for progenitor cell migration. This appears to be the first paper to focus on this very important field in dental pulp biology.
Dental Pulp Stem Cells, Niches, and Notch Signaling in Tooth Injury
Authors: Mitsiadis T.A. , Feki A. , Papaccio G. , Catón J.
Published: June 2011

Stem cells guarantee tissue repair and regeneration throughout life. The decision between cell self-renewal and differentiation is influenced by a specialized microenvironment called the ‘stem cell niche’. In the tooth, stem cell niches are formed at specific anatomic locations of the dental pulp. The microenvironment of these niches regulates how dental pulp stem cell populations participate in tissue maintenance, repair, and regeneration. Signaling molecules such as Notch proteins are important regulators of stem cell function, with various capacities to induce proliferation or differentiation. Dental injuries often lead to odontoblast apoptosis, which triggers activation of dental pulp stem cells followed by their proliferation, migration, and differentiation into odontoblast-like cells, which elaborate a reparative dentin. Better knowledge of the regulation of dental pulp stem cells within their niches in pathological conditions will aid in the development of novel treatments for dental tissue repair and regeneration.
Mediators of Inflammation and Regeneration
Authors: Cooper P.R. , McLachlan J.L. , Simon S. , Graham L.W. , Smith A.J.
Published: June 2011

Characterization of the molecular response under caries lesions requires a robust and reliable transcript isolation system, and analysis of data indicated that collection of extracted teeth in either liquid nitrogen/RNA-stabilizing solution facilitated this. Subsequent transcriptional analysis indicated higher general activity in carious pulps, while characterization of inflammatory mediators, including cytokines and S100 proteins, highlighted increasing expression levels associated with both microbial front progression and elevated cellular immune response. Analysis of the pleiotropic hormone adrenomedullin (ADM) indicated that transcript and protein levels are increased in pulpal tissue during caries, and that protein levels sequestered in dentin due to primary dentinogenesis are comparable with those of TGF-β1. Expression analysis of a leucine-rich-repeat-containing protein (LRRC15/Lib) indicated that this highly conserved molecule was up-regulated during caries, is transcriptionally regulated by pro-inflammatory stimuli, and is relatively abundant in mineralized tissues.
Toll-like Receptors, LPS, and Dental Monomers
Authors: Schmalz G. , Krifka S. , Schweikl H.
Published: June 2011

Unreacted monomers released from dental resin-based composites at non-cytotoxic concentrations cause a depletion of glutathione and an increase of reactive oxygen species (ROS), leading to, e.g., DNA damage and apoptosis. ROS-sensitive MAP-kinases are activated by HEMA and TEGDMA. MAP-kinases are also involved in the bacteria-triggered cell responses of the innate immune system, e.g., after bacterial lipopolysaccharide (LPS) binding to the Toll-like receptor (TLR) 4. Therefore, both bacteria and monomers imply environmental stress to pulp tissue, and they may influence the target cell reactions in a combined way. In macrophages, cell-surface antigens and cytokines were up-regulated after exposure to LPS, but TEGDMA caused a significant down-regulation. Regulation was dependent on exposure time, indicating that LPS and TEGDMA act differently on MAP-kinases. Furthermore, the cell type played a decisive role. Inhibition of the immune response may result in a decrease in inflammatory symptoms and/or a reduced defense capacity against bacteria.
Who Benefits From Chatting, and Why?
Authors: Van Zalk Maarten H. W. , Branje Susan J. T. , Denissen Jaap , Van Aken Marcel A. G. , Meeus Wim H. J.
Published: June 2011

The current study aimed to provide more insight into the role of online chatting in young adults’ emotional adjustment. A model was tested that takes into account (a) extraversion of individuals who communicate online, (b) the kind of peers these individuals communicate with online (i.e., online-exclusive peers vs. friends), and (c) the extent to which effects of online chatting on emotional adjustment are mediated by individuals’ ability to provide support to others. Young adults (age M = 18.9) filled out questionnaires about themselves and their fellow students at three measurements with a 4-month interval. Results showed that only for less extraverted individuals, chatting with peers found exclusively online directly predicted higher self-esteem and indirectly predicted less depressive symptoms through increases in supportiveness. Thus, results supported a model of social compensation where effects of online chatting with online-exclusive peers improved young adults’ emotional adjustment.
The Information Content of Goodwill Impairments and SFAS 142
Authors: Bens Daniel A. , Heltzer Wendy , Segal Benjamin
Published: June 2011

Accounting standard setters face a perpetual challenge in balancing relevance and reliability when establishing generally accepted accounting principles. This tension is especially heightened when the nature of the economic information concerns intangible assets. This article presents exploratory evidence about standard setters’ response to this challenge by examining whether Statement of Financial Accounting Standards No. 142 (SFAS 142): Goodwill and Other Intangible Assets altered the information content of goodwill write-offs. To more accurately capture the information of goodwill write-offs, the authors first create a model to estimate expected impairments. The difference between actual write-offs and expected write-offs represents write-off surprises or unexpected goodwill write-offs. The authors document a negative and significant stock market reaction to unexpected goodwill write-offs. On a cross-sectional basis, they find that the market reaction is attenuated for firms with low information asymmetry (their proxy is a high analyst following) and for firms that find it relatively costly to implement impairment tests (their proxy is the inverse of firm size). The authors find no variation in market reaction based on firm complexity (their proxy is the number of firm segments). The negative reaction for the high information asymmetry and larger firms weakens following the adoption of SFAS 142. The latter result is consistent with SFAS 142 critics’ claims that more relevant accounting information, captured by fair value methods, is difficult to implement reliably and thus can reduce the information content of accounting reports.
A Systematic Comparison of Microsimulation Models of Colorectal Cancer
Authors: Kuntz Karen M. , Lansdorp-Vogelaar Iris , Rutter Carolyn M. , Knudsen Amy B. , van Ballegooijen Marjolein , Savarino James E. , Feuer Eric J. , Zauber Ann G.
Published: June 2011

Background. As the complexity of microsimulation models increases, concerns about model transparency are heightened. Methods. The authors conducted model “experiments” to explore the impact of variations in “deep” model parameters using 3 colorectal cancer (CRC) models. All natural history models were calibrated to match observed data on adenoma prevalence and cancer incidence but varied in their underlying specification of the adenocarcinoma process. The authors projected CRC incidence among individuals with an underlying adenoma or preclinical cancer v. those without any underlying condition and examined the impact of removing adenomas. They calculated the percentage of simulated CRC cases arising from adenomas that developed within 10 or 20 years prior to cancer diagnosis and estimated dwell time—defined as the time from the development of an adenoma to symptom-detected cancer in the absence of screening among individuals with a CRC diagnosis. Results. The 20-year CRC incidence among 55-year-old individuals with an adenoma or preclinical cancer was 7 to 75 times greater than in the condition-free group. The removal of all adenomas among the subgroup with an underlying adenoma or cancer resulted in a reduction of 30% to 89% in cumulative incidence. Among CRCs diagnosed at age 65 years, the proportion arising from adenomas formed within 10 years ranged between 4% and 67%. The mean dwell time varied from 10.6 to 25.8 years. Conclusions. Models that all match observed data on adenoma prevalence and cancer incidence can produce quite different dwell times and very different answers with respect to the effectiveness of interventions. When conducting applied analyses to inform policy, using multiple models provides a sensitivity analysis on key (unobserved) “deep” model parameters and can provide guidance about specific areas in need of additional research and validation.
Fibrinogen organization at the cell-material interface directs endothelial cell behavior
Authors: Gugutkov Dencho , González-García Cristina , Altankov George , Salmerón-Sánchez Manuel
Published: June 2011

Fibrinogen (FG) adsorption on surfaces with controlled fraction of —OH groups was investigated with AFM and correlated to the initial interaction of primary endothelial cells (HUVEC). The —OH content was tailored making use of a family of copolymers consisting of ethyl acrylate (EA) and hydroxyl ethyl acrylate (HEA) in different ratios. The supramolecular distribution of FG changed from an organized network-like structure on the most hydrophobic surface (—OH 0) to dispersed molecular aggregate one as the fraction of —OH groups increases, indicating a different conformation by the adsorbed protein. The best cellular interaction was observed on the most hydrophobic (—OH 0) surface where FG assembled in a fibrin-like appearance in the absence of any thrombin. Likewise, focal adhesion formation and actin cytoskeleton development was poorer as the fraction of hydroxy groups on the surface was increased. The biological activity of the surface-induced FG network to provide 3D cues in a potential tissue engineered scaffold, making use of electrospun PEA fibers (—OH0), seeded with human umbilical vein endothelial cells was investigated. The FG assembled on the polymer fibers gave rise to a biologically active network able to direct cell orientation along the fibers (random or aligned), promote cytoskeleton organization and focal adhesion formation.
Optimal synthesis of a two-stage asymmetric damper of an automotive suspension considering wheel camber variations
Authors: Balike K P , Rakheja S , Stiharu I G
Published: June 2011

The influences of damper asymmetry on the camber angle variations of a double wishbone type of suspension, together with the dynamic responses under measured urban road inputs at different vehicle velocities, were investigated. Simulation studies employing a kineto-dynamic quarter-car model comprising a bilinear damper revealed complex dependence of the dynamic and kinematic responses on the vehicle forward velocity. The study further revealed an increase in camber angle variations with an increase in damper asymmetry, while this increment showed a non-linear relationship with the suspension deflection. The camber angle variation under road inputs thus poses an additional design compromise apart from those associated with the well-established conflicting measures of ride comfort, rattle space, and road-holding properties. The study also investigated the synthesis of an optimal two-stage asymmetric damper to yield a compromise between these conflicting performance measures under road inputs at different vehicle forward velocities with consideration of minimal camber angle variations. A composite performance index, comprising the ride comfort and road-holding measures with limit constraint on camber angle variation, was formulated to seek optimal damper parameters. The results showed that an optimal asymmetric damper could be identified to yield acceptable design compromise over a wide speed range.
Pareto Optimization-Based Tradeoff Between the Damping Force and the Sensed Relative Displacement of a Self-sensing Magnetorheological Damper
Authors: Wang Dai-Hua , Bai Xian-Xu
Published: June 2011

In order to make the best compromise between the damping force and the linearity of the integrated relative displacement sensor (IRDS) of an integrated relative displacement self-sensing magnetorheological damper (IRDSMRD), a Pareto optimization-based method, which optimizes the key structural parameters by taking the damping force and the linearity of the IRDS of the IRDSMRD as the objective functions, is proposed and realized in this article. The Pareto front, representing the best tradeoff between the damping force and the linearity of the IRDS of the IRDSMRD, is obtained by considering that the maximum magnetomotive force applied to the exciting coil of the IRDSMRD is constant. Three IRDSMRDs with different piston modules, which are determined according to the Pareto optimal solutions, are developed and tested. The research results indicate that every point on the Pareto front is an optimal solution that compromises the damping force and the linearity of the IRDS of the IRDSMRD and the optimal damping force of the IRDSMRD with a certain linearity of the IRDS as well as the optimal linearity of the IRDS with a certain damping force can be determined according to the Pareto front for a specific application.
Cardiovascular Disease Prevention Preferences of a Sample of Urban American Indians
Authors: Keim Kathryn S. , Agruss Janyce Cagan , Williams Ellen M. , Fogg Louis , Minnick Ann , Catrambone Catherine , Rothschild Steven
Published: June 2011

This study identified program delivery preferences and barriers to physical activity and healthy eating. Ninety-nine urban dwelling American Indians completed a questionnaire at powwows, community events, and a community health center. Most frequently selected program delivery preferences were coaching or other human contact, with fewer willing to use computer or telephone coaching. Fifty-six selected attending 8, 12, or 16 sessions. Most frequently selected barriers to physical activity were lack of time ( n = 48) and pain from existing problems ( n = 33). Frequently identified barriers to eating healthy foods included expense ( n = 42), uncertainty regarding what foods are healthy ( n = 25), extra time needed for preparation ( n = 22), and lack of knowledge of how to prepare healthy food ( n = 22). Findings showed the need for programs to focus on decreasing the barriers of time for physical activity and healthy eating and encourage doing organized physical activity (not necessarily exercise) with others to increase physical activity.
Why and When do Stores With Satisfied Employees Have Satisfied Customers?
Authors: Grandey Alicia A. , Goldberg Lori S. , Pugh S. Douglas
Published: June 2011

Stores with more satisfied employees also have greater customer satisfaction (CS). Two theoretical mechanisms have been employed to explain why: affective transfer (i.e., emotional contagion) and performance motivation (i.e., extra-effort service behaviors). The authors provide a constructive replication of these relationships, while also arguing for an important boundary condition: store busyness. The authors suggest that in busy stores, employee attitudes (a) are less likely to be emotionally expressed by employees and “caught” by customers, and (b) are less likely to emerge as extra-effort performance, compared to slow stores. In a survey study of 328 warehouse-style retail stores, with multisource and time-separated data and controlling for contextual features, the authors support both direct affective transfer and indirect effects via an objective performance measure (i.e., speed of response to customers' requests for help). However, these associations depended on store busyness: store employee satisfaction had less influence on CS and service responsiveness in busy stores compared to slower stores. The results suggest several practical implications. For example, interventions targeting employee morale will have a greater effect on customer reactions in “less successful” stores with fewer sales transactions, while busy stores will see more benefit from interventions targeting other factors.
Dealing With Complex Causality in Realist Synthesis
Authors: Sager Fritz , Andereggen Céline
Published: June 2011

In this article, the authors state two arguments: first, that the four categories of context, politics, polity, and policy make an adequate framework for systematic review being both exhaustive and parsimonious; second, that the method of qualitative comparative analysis (QCA) is an appropriate methodical approach for gaining realistic results that are useful for political practice. Instead of providing unsatisfactory monocausal explanations, the approach identifies different combinations of conditions leading to a given outcome. The authors illustrate their points with a two-step multi-value QCA (mvQCA) of 17 transport policy cases in Switzerland.
Why international norms disappear sometimes
Authors: Panke Diana , Petersohn Ulrich
Published: June 2011

This article addresses the empirical puzzle as to why some formerly deeply embedded international norms either incrementally or rapidly lose their prescriptive status and, in the extreme, can even cease to exist. Why is it that some norms are replaced while others simply disappear? The IR literature has rich explanations for norm creation, diffusion and socialization, yet there is a theoretical and empirical gap on both the dynamics and scope conditions for the degeneration of international norms. Thus, we develop hypotheses on processes and outcomes of norm disappearances that are tested with a series of qualitative studies. Norm degenerations require the presence of actors who challenge the norm and the absence of central enforcement authorities or individual states that are willing and capable of punishing norm violations. Moreover, our study shows that norms are likely to be abolished swiftly if the environment is unstable and rapidly changing and if norms are highly precise. In contrast, norms are likely to become incrementally degenerated if the environment is relatively stable and if norms are imprecise. Both processes lead to norm substitutions, provided that competing norms are present. If rival norms are absent, norms simply disappear without being replaced.
L1 transfer in the acquisition of manner and path in Spanish by native speakers of English
Authors: Larrañaga Pilar , Treffers-Daller Jeanine , Tidball Françoise , Ortega Mari-carmen Gil
Published: June 2011

In this article the authors argue that L1 transfer from English is not only important in the early stages of L2 acquisition of Spanish, but remains influential in later stages if there is not enough positive evidence for the learners to progress in their development (Lefebvre, White, & Jourdan, 2006). The findings are based on analyses of path and manner of movement in stories told by British students of Spanish ( N = 68) of three different proficiency levels. Verbs that conflate motion and path, on the one hand, are mastered early, possibly because the existence of Latinate path verbs, such as enter and ascend in English, facilitate their early acquisition by British learners of Spanish. Contrary to the findings of Cadierno (2004) and Cadierno and Ruiz (2006), the encoding of manner, in particular in boundary crossing contexts, seems to pose enormous difficulties, even among students who had been abroad on a placement in a Spanish-speaking country prior to the data collection. An analysis of the frequency of manner verbs in Spanish corpora shows that one of the key reasons why students struggle with manner is that manner verbs are so infrequent in Spanish. The authors claim that scarce positive evidence in the language exposed to and little or no negative evidence are responsible for the long-lasting effect of transfer on the expression of manner.
A profile of Australian travel journalists’ professional views and ethical standards
Authors: Hanusch Folker
Published: June 2011

Despite significant changes in mainstream journalism in recent decades, journalistic fields beyond the news have been little explored. In an attempt to contribute to a deeper understanding of such fields, this article examines the role perceptions of 85 Australian travel journalists. By viewing travel journalism as a distinct field of practice that is affected by a unique mix of influences, this study identifies five dimensions of practitioners’ role perceptions. These relate to travel journalists’ views of themselves as Cultural Mediators, Critics, Entertainers, Information Providers and Travellers. In addition, the study examines in some depth the ethical standards of travel journalists. Determinants of these views and standards are explored. The study argues that, in light of travel journalists’ increasingly important role in reporting about foreign places, more remains to be done to promote travel stories that show a deeper understanding of other cultures and which contain a more critical appraisal of destinations.
Questioning the ‘bleeding obvious’: What’s the point of researching journalism?
Authors: Harcup Tony
Published: June 2011

Within higher education, journalism studies is often seen as an uncomfortable bedfellow with journalism training; there is evidence of a pervasive disconnect between research and teaching, as between theory and practice. However, voices within journalism education are calling for a more critical curriculum informed by scholarly research. There are suggestions that the journalists now doing much of the teaching within university journalism departments could play a key role in establishing a more critical journalism education and, by doing so, contributing towards more critical forms of journalism. Within this context, do journalists-turned-journalism-educators see any point in researching journalism or would they rather simply pass on vocational skills to the next generation? This article is based on asking a sample group of such ‘hackademics’ working in UK and/or Irish universities about the utility of scholarly inquiry into journalism. The article suggests that exploring ostensibly ‘bleeding obvious’ aspects of journalism may not be the pointless exercise derided by some commentators; rather, it could be precisely what journalism educators ought to be doing.
Western journalism’s ‘Other’: The legacy of the Cold War in the comparative study of journalism
Authors: Szpunar Piotr M.
Published: June 2011

In 1995, when discussing the critiques of the New York Times made by academics and pundits, Michael Schudson stated that the newspaper has never been anything ‘like the late, unlamented Pravda’. This comparison, utilized in a variety of ways over time, originated in the canonical Four Theories of the Press (Siebert et al., 1963[1956]). This juxtaposition, more broadly, uses the Cold War ‘Other’ to define what western journalism is, or should be, by what it is not. Building on the theoretical insights of Fredrik Barth and Edward Said, this article traces the construction of this ‘Other’ in the study of western journalism. Ultimately, the author argues that the use of this ‘Other’ in the construction of a coherent, meaningful definition of western journalism, and in the explication and justification of journalistic practice therein, constitutes a problematic guide in thinking about the development of journalism in nations that were historically part of this ‘Other’.
Player Character Engagement in Computer Games
Authors: Lankoski Petri
Published: June 2011

This article argues how players can control a player character influence interpretation and facilitate engagement within a game. Engagement with player characters can be goal-related or empathic, where goal-related engagement depends on affects elicited by goal-status evaluations whereas characters facilitate empathic engagement. The concepts of recognition, alignment, and allegiance are used to describe how engagement is structured in games. Recognition describes aspects of character interpretation. Alignment describes what kind of access players have to a character’s actions, knowledge, and affects. Allegiance describes how characters elicit sympathy or antipathy through positive or negative evaluation of the character.