bluuebunny/crossref_metadata_2025 huggingface dataset:
Viewing a Face (Especially One's Own Face) Being Touched Enhances Tactile Perception on the Face
Authors: Serino Andrea , Pizzoferrato Francesca , Làdavas Elisabetta
Published: May 2008

Observing touch on another person's body activates brain regions involved in tactile perception, even when the observer's body is not directly stimulated. Previous work has shown that in some synaesthetes, this effect induces a sensation of being touched. The present study shows that if perceptual thresholds are experimentally manipulated, viewing touch can modulate tactile experience in nonsynaesthetes as well. When observers saw a face being touched by hands, rather than a face being merely approached by hands, they demonstrated enhanced detection of subthreshold tactile stimuli on their own faces. This effect was specific to observing touch on a body part, and was not found for touch on a nonbodily stimulus, namely, a picture of a house. In addition, the effect was stronger when subjects viewed their own faces rather than another person's face. Thus, observing touch can activate the tactile system, and if perceptual thresholds are manipulated, such activation can result in a behavioral effect in nonsynaesthetes. The effect is maximum if the observed body matches the observer's body.
Lacking Power Impairs Executive Functions
Authors: Smith Pamela K. , Jostmann Nils B. , Galinsky Adam D. , van Dijk Wilco W.
Published: May 2008

Four experiments explored whether lacking power impairs executive functioning, testing the hypothesis that the cognitive presses of powerlessness increase vulnerability to performance decrements during complex executive tasks. In the first three experiments, low power impaired performance on executive-function tasks: The powerless were less effective than the powerful at updating (Experiment 1), inhibiting (Experiment 2), and planning (Experiment 3). Existing research suggests that the powerless have difficulty distinguishing between what is goal relevant and what is goal irrelevant in the environment. A fourth experiment established that the executive-function impairment associated with low power is driven by goal neglect. The current research implies that the cognitive alterations arising from powerlessness may help foster stable social hierarchies and that empowering employees may reduce costly organizational errors.
Forgetting and Recovering the Unforgettable
Authors: Smith Steven M. , Moynan Sarah C.
Published: May 2008

Two experiments demonstrated striking, reversible forgetting effects that occurred even for a list of expletives. The experiments used a procedure based on the classic memory mechanisms of interference and retrieval cuing. Interference reduced recall dramatically, although appropriate cues triggered complete recovery. Distinctive, emotionally charged materials were quite susceptible to the forgetting and recovery effects. Thus, powerful forgetting effects can be obtained when participants have no intentions to forget and the materials involved are distinctive, emotional materials with sexual and violent content. This forgetting is reversible with appropriate cues. The false-memory debate can and must be informed by experimental investigations not only of false memories, but also of blocked and recovered memories.
In the Footsteps of Biological Motion and Multisensory Perception
Authors: Saygin Ayse Pinar , Driver Jon , de Sa Virginia R.
Published: May 2008

Observers judged whether a periodically moving visual display (point-light walker) had the same temporal frequency as a series of auditory beeps that in some cases coincided with the apparent footsteps of the walker. Performance in this multisensory judgment was consistently better for upright point-light walkers than for inverted point-light walkers or scrambled control stimuli, even though the temporal information was the same in the three types of stimuli. The advantage with upright walkers disappeared when the visual “footsteps” were not phase-locked with the auditory events (and instead offset by 50% of the gait cycle). This finding indicates there was some specificity to the naturally experienced multisensory relation, and that temporal perception was not simply better for upright walkers per se. These experiments indicate that the gestalt of visual stimuli can substantially affect multisensory judgments, even in the context of a temporal task (for which audition is often considered dominant). This effect appears to be constrained by the ecological validity of the particular pairings.
Fighting Death With Death
Authors: Hayes Joseph , Schimel Jeff , Williams Todd J.
Published: May 2008

According to terror management theory, the annihilation of people who threaten one's worldview should serve the function of defending that worldview. The present research assessed this hypothesis. A sample of Christian participants read either a worldview-threatening news article reporting on the Muslimization of Nazareth or a non-threatening article about the aurora borealis. Half of the participants in the worldview-threat condition were informed at the end of the article that a number of Muslims had died in a plane crash on their way to Nazareth. Although reading the threatening news article increased death-thought accessibility and worldview defense relative to reading the neutral article, these increases were not observed among participants who learned that a number of Muslims were dead. Implications for understanding protracted intergroup conflict are discussed.
Reading Between the Lies
Authors: Porter Stephen , ten Brinke Leanne
Published: May 2008

The widespread supposition that aspects of facial communication are uncontrollable and can betray a deceiver's true emotion has received little empirical attention. We examined the presence of inconsistent emotional expressions and “microexpressions” (1/25–1/5 of a second) in genuine and deceptive facial expressions. Participants viewed disgusting, sad, frightening, happy, and neutral images, responding to each with a genuine or deceptive (simulated, neutralized, or masked) expression. Each 1/30-s frame (104,550 frames in 697 expressions) was analyzed for the presence and duration of universal expressions, microexpressions, and blink rate. Relative to genuine emotions, masked emotions were associated with more inconsistent expressions and an elevated blink rate; neutralized emotions showed a decreased blink rate. Negative emotions were more difficult to falsify than happiness. Although untrained observers performed only slightly above chance at detecting deception, inconsistent emotional leakage occurred in 100% of participants at least once and lasted longer than the current definition of a microexpression suggests. Microexpressions were exhibited by 21.95% of participants in 2% of all expressions, and in the upper or lower face only.
A two‐week monitoring of self‐reported arousal, worry and attribution among persons with annoyance attributed to electrical equipment and smells
Authors: PERSSON ROGER , CARLSSON EEK FRIDA , ÖSTERBERG KAI , ØRBÆK PALLE , KARLSON BJÖRN
Published: May 2008

Non‐patients attributing annoyance to either smells (smell annoyed; SA, n= 29) or electrical equipment (electrically annoyed; EA, n= 17), or both (generally annoyed; GA, n= 38), were monitored for 2 weeks through daily self‐ratings of arousal (stress), sleep disturbances, health complaints, worry about hypersensitivity reactions, avoidance behaviors, and attributions of health complaints to electrical equipment and smells. In parallel, a demographically matched reference group was followed (n= 56). GA persons reported higher arousal (stress), more subjective health complaints, and more sleep disturbances than the other groups. About 60% in the GA and EA groups reported intentional avoidance behavior, compared to 31% in the SA group and 2% of the referents. Worry and attribution to environmental factors was also more frequent among GA persons than in the other groups. Thus, even at sub‐clinical levels, environmental annoyance generalized to several triggers seems to be associated with behaviors commonly observed among patients with idiopathic environmental intolerance.
Psychosocial factors and reading difficulties: Students with reading difficulties drawn from a representative population sample
Authors: UNDHEIM ANNE MARI , SUND ANNE MARI
Published: May 2008

In a representative sample of 2,464 Norwegian adolescents, aged 12–15 years, 7.8% (n= 191) reported reading difficulties (RD). No gender difference was found. Adolescents with RD were compared to classmates on psychosocial variables. In univariate analysis, RD adolescents report higher levels of depressive symptoms, more school stress, worried more about going to school, had lower school grades and lower attachment to parents than those without RD. They also scored lower on Global Self‐worth and on Social Acceptance scales. Further, they reported reduced levels of psycho‐functioning during the previous year because of mental health problems, they had received more help and had used more medication for such problems. In a multivariate logistic regression analysis, receiving help for mental health problems and reduced psycho‐functioning showed the strongest associations with student RD status. No gender interactions were found. The study demonstrated important differences between adolescents with and without RD.
A Bayesian Statistical Model for End Member Analysis of Sediment Geochemistry, Incorporating Spatial Dependences
Authors: Palmer Mark J. , Douglas Grant B.
Published: May 2008

An important problem in the management of water supplies is identifying the sources of sediment. The paper develops a Bayesian approach, utilizing an end member model, to estimate the proportion of various sources of sediments in samples taken from a dam. This approach not only allows for the incorporation of prior knowledge about the geochemical compositions of the sources (or end members) but also allows for correlation between spatially contiguous samples and the prediction of the sediment's composition at unsampled locations. Sediments that were sampled from the North Pine Dam in south-east Queensland, Australia, are analysed to illustrate the approach.
Statistical Methods to Evaluate Health Effects Associated with Major Sources of Air Pollution: A Case-Study of Breathing Patterns During Exposure to Concentrated Boston Air particles
Authors: Nikolov Margaret C. , Coull Brent A. , Catalano Paul J. , Diaz Edgar , Godleski John J.
Published: May 2008

We conduct a case-study evaluating the source-specific effects of particulate matter on respiratory function. Using a structural equation approach, we assess the effect of different receptor models on the estimated source-specific effects for univariate respiratory response. Furthermore, we extend the structural equation model by placing a factor analysis model on the response to represent the measured respiratory responses in terms of underlying respiratory patterns. We estimate the particulate matter source-specific effects on respiratory rate, accentuated normal breathing and airway irritation and find a strong increase in airway irritation that is associated with exposure to motor vehicle particulate matter.
Conference Calls and Stock Price Volatility in the Post‐Reg FD Era
Authors: Dell'Acqua Alberto , Perrini Francesco , Caselli Stefano
Published: May 2008

Past research has documented that the utilisation of conference calls is greater in the high tech sector than in other industries. Do high tech firms benefit from that? This study attempts to answer this question by examining the impact of ‘post‐Reg FD’ conference calls on the price volatility of high tech firms listed in the US market. We find evidence that more open conference calls results in lower idiosyncratic volatility.
Oral prednisone taper following intravenous steroids fails to improve disability or recovery from relapses in multiple sclerosis
Authors: Perumal J. S. , Caon C. , Hreha S. , Zabad R. , Tselis A. , Lisak R. , Khan O.
Published: May 2008

Background:  A short course of intravenous methylprednisolone (IVMP) followed by oral prednisone taper (OPT) is often used for the treatment of relapses in multiple sclerosis (MS). We examined the effect of IVMP plus OPT compared with IVMP only on neurologic disability 1 year after treatment of a relapse in patients with relapsing–remitting multiple sclerosis..

Methods:  Two hundred eighty‐five consecutive relapses were analyzed in a retrospective fashion. One hundred fifty‐two patients with a total of 171 relapses received IVMP plus an OPT at the time of relapse whilst 112 patients who experienced 114 relapses received IVMP without OPT.

Results:  There was no difference between the two groups in the baseline characteristics as well as the mean or categorical EDSS at baseline, at the time of relapse confirmation, and at months 3, 6 and 12 after relapse confirmation.

Conclusion:  Our observations suggest that OPT following treatment with IVMP for an MS relapse does not lead to improved neurologic outcome after 12 months compared with treatment with IVMP only. Moreover, our findings raise concerns regarding the common practice of using OPT following IVMP. Further studies are indicated to validate our findings and minimize exposure to systemic corticosteroids, well known for systemic toxicity.
Innovation Ideas and Regional Characteristics: Product Innovations and Export Entrepreneurship by Firms in Swedish Regions
Authors: ANDERSSON MARTIN , JOHANSSON BÖRJE
Published: May 2008

ABSTRACT  This paper focuses upon the ways in which characteristics of regions in regards to knowledge sources, communication opportunities, and absorptive capacity influence the development of innovation ideas among existing and potential entrepreneurs. We formulate a model where entrepreneurs or innovating firms introduce new products in a quasi‐temporal setting. Market conditions are characterised by monopolistic competition between varieties belonging to the same product group, in which there is entry and exit of varieties. A stochastic process is assumed to generate new innovation ideas as time goes by, and a firm (entrepreneur) who receives such an idea has to transform the idea to an innovation, which in the model is specified as a particular variety combined with a specific destination market. The theoretical model is used as a reference when formulating two regression models, with which we estimate how a set of regional characteristics are associated with the likelihood of innovation ideas across Swedish local labour market regions. In one model, we examine the emergence of new export varieties, and in the second model, we investigate the appearance of new export firms. Results are consistent with the assumption that knowledge and information flows have a positive influence on the frequency of arrival of innovation ideas to firms.
International Trade and the Changing Demand for Skilled Workers in High‐Tech Manufacturing
Authors: SILVA JULIE A.
Published: May 2008

ABSTRACT States and localities in the U.S. put considerable effort into attracting and maintaining high‐tech manufacturing industries to preserve manufacturing employment. However, little work has examined whether high‐tech industries respond differently than traditional manufacturing to changing trade pressures. This study investigates the impact of international trade on skilled and unskilled labor demand across manufacturing sectors. Results of this study indicate that changes in exchange rates and trade orientation have similar effects across high‐tech and traditional manufacturing sectors. In addition, findings suggest that there is a high degree of variation in the trade‐related effects on labor demand across individual high‐tech sectors, and that the direction of these effects often runs counter to the predictions of traditional trade theory.
Does a Rising Tide Lift All Metropolitan Boats? Assessing Poverty Dynamics by Metropolitan Size and County Type
Authors: PARTRIDGE MARK D. , RICKMAN DAN S.
Published: May 2008

ABSTRACT  This paper examines the relationship between U.S. metropolitan county employment growth and poverty. Differential job growth–poverty linkages are found across metropolitan size and type of county. Own‐county employment growth significantly reduces central‐county poverty in large metropolitan areas relative to suburban county poverty. Compared with larger metropolitan areas, broader metropolitan‐wide job growth has more poverty reducing benefits in medium and smaller metropolitan areas, suggesting fewer metropolitan‐wide job‐accessibility constraints. The results suggest that targeted place‐based efforts to spur job growth may help reduce poverty.
Low‐Income Dynamics in Canadian Communities: A Place‐Based Approach
Authors: CHOKIE MENGISTEAB , PARTRIDGE MARK D.
Published: May 2008

ABSTRACT  Canadian poverty rates have persisted at disappointingly high levels despite almost 15 years of continuous economic growth. The problem is exacerbated by some communities and neighborhoods having exceedingly high poverty, including very high rates for vulnerable demographic groups, such as aboriginals and recent immigrants. We investigate low‐income rates (poverty rates) for 2,400 Canadian “communities” over the 1981–2001 period. By focusing on communities, we fill a void in the related Canadian literature, which tends to focus on individuals, case studies, or more aggregate measures, such as provinces. Our approach allows us to assess the role of place‐based policies. Particular attention is given to communities with differing shares of aboriginal Canadians and recent immigrants. One novel feature is our analysis of both “short‐term” and “long‐term” causes of differential community poverty rates. The results suggest that community low‐income rates are more affected by initial economic conditions in the short term, with certain demographic factors becoming relatively more important in the long run.
INFLATION AND THE DISPERSION OF REAL WAGES*
Authors: Kumar Alok
Published: May 2008

The article studies the effects of inflation on real wage dispersion in a search‐monetary framework. The economy is characterized by frictions in both the goods and the labor markets. In the goods market, buyers and sellers bargain over prices, whereas in the labor market firms post wage offers. In equilibrium, a lower inflation rate increases the dispersion of real wages. This result is consistent with both the observed trends in wage dispersion and the inflation rate witnessed in the 1980s and the 1990s in the United States and the empirical literature linking reduced inflation to greater wage dispersion.
ON FINANCE AS A THEORY OF TFP, CROSS‐INDUSTRY PRODUCTIVITY DIFFERENCES, AND ECONOMIC RENTS*
Authors: Erosa Andrés , Hidalgo Cabrillana Ana
Published: May 2008

We develop a theory of capital‐market imperfections to study how the ability to enforce contracts affects resource allocation across entrepreneurs of different productivities, and across industries with different needs for external financing. The theory implies that countries with a poor ability to enforce contracts are characterized by the use of inefficient technologies, low aggregate TFP, large differences in labor productivity across industries, and large employment shares in industries with low productivity. These implications are supported by the empirical evidence. The theory also suggests that entrepreneurs have a vested interest in maintaining a status quo with low enforcement.
BAILOUTS IN FEDERATIONS: IS A HARD BUDGET CONSTRAINT ALWAYS BEST?*
Authors: Besfamille Martin , Lockwood Ben
Published: May 2008

This article analyses hard and soft budget constraints in a federation, where there is a moral hazard problem between the central and the regional governments. Regional governments can avoid a bailout from the center by exerting costly effort. In this setting, a hard budget constraint is not always optimal because it can provide excessive incentives for high effort, and thus discourage investment that is socially efficient. Thus, a hard budget constraint can imply the opposite kind of inefficiency that emerges under a soft budget constraint, where the common pool problem can give rise to inefficiently low effort and overinvestment.
The Health Risk Behaviours and Social Connectedness of Adolescents in Immigrant Families: Evidence from Australia
Authors: Brandon Peter
Published: May 2008

Using data from Australia, health behavior outcomes and the social connectedness of adolescents in immigrant families are contrasted with the outcomes of adolescents in non‐immigrant families. Findings suggest that first and second generation adolescents are less likely to drink alcohol and lack social support than third generation adolescents, but more likely not to be physically active and not to have membership to a social club or group than third generation adolescents. Second generation adolescents are more likely to smoke than third generation adolescents. Findings suggest that immigrant adolescents appear protected from negative risks, yet at the same time, do not benefit from Australia's cultural traditions for physical activity and social participation. Across generations, however, social participation and physical activity increase. Lastly, as length of time in Australia increases, the protective effect of the immigrant family against some negative risks wanes. Overall, the assimilation process leads adolescents in immigrant families to adopt Australia's prevailing social customs of health and social behaviors.
Military Brides and Refugees: Vietnamese American Wives and Shifting Links to the Military, 1980 – 2000
Authors: Hidalgo Danielle Antoinette , Bankston Carl L.
Published: May 2008

Since the immigration legislation of 1965, marriage to American citizens and resident aliens has been one of the primary paths for migration to the United States. Despite the rapid growth of the Asian American population over the course of the late twentieth century, Asian Americans had still reached only 3 per cent of all Americans by 2000, meaning that Asian marriage migration to the United States has been largely through marriage to non‐Asians. In this study, we look at exogamy among Vietnamese Americans using U. S. Census data (1980, 1990, and 2000) from 5 per cent PUMS sets made available through the IPUMS project. We ask: (1) What are the predictors of exogamy among Vietnamese Americans? (2) How do the rates of exogamy of Vietnamese American women compare to those of Vietnamese American men? (3) How have the predictors of exogamy and the apparent characteristics of the exogamously married changed over the decades of refugee movement from Vietnam to North America? We review data from the years 1980, 1990, and 2000. In the assimilationist view of immigration associated with the classic work of Milton M. Gordon, exogamy is the final stage of immigrant incorporation into a host country. Migration through marriage, which has become a major source of immigration to the United States since the Immigration Act of 1965, reverses this assimilationist pattern, placing marriage before immigration and incorporation, or at the earliest stages of immigration and incorporation. Our findings are relevant to understanding the specific Vietnamese experience in the United States. They highlight the continuing but declining importance of the Vietnam War in creating close connections between Vietnamese and other people in the United States, even after the war had ended. The findings also suggest how these connections changed as a result of Vietnamese mass migration to America.
Women’s experience of physical activity following breast cancer treatment
Authors: Larsson Ingalill L. , Jönsson Carita , Olsson Ann C. , Gard Gunvor , Johansson Karin
Published: May 2008

Physical activity is of great benefit to women treated for breast cancer and can even be vital. The aim of this qualitative study was to describe how women treated for breast cancer experience physical activity after surgery. Twelve women, strategically selected according to hospital, age and length of time since surgery, took part in a semi‐structured interview. A qualitative method with a phenomenographic approach was used.

The result indicates that the incentive to remain or return to a normal physical condition is an important motive for physical activity after breast cancer surgery. The experience of physical activity was, from the women’s perspective, expressed in (i) compliance to instructions and need for support, (ii) struggle to get back to normal and fear of negative side‐effects, (iii) a wish to stay normal and not allow limitations and (iv) getting control of the situation with new strategies. In conclusion, instructions and motivation are important in starting up and/or continuing physical activity after breast cancer treatment. While in considering the vital benefits of physical activity for breast cancer patients healthcare professionals, and in particular physiotherapists, must be aware of the need for information and the patients’ motive for exercise and physical activity to be able to guide and encourage them individually.

The professionals must also understand the need for empowerment for these women to take control over their lives and to allow the limitations that eventually occur.
In search of the microbe/mineral interface: quantitative analysis of bacteria on metal surfaces using vertical scanning interferometry
Authors: WATERS M. S. , STURM C. A. , EL‐NAGGAR M. Y. , LUTTGE A. , UDWADIA F. E. , CVITKOVITCH D. G. , GOODMAN S. D. , NEALSON K. H.
Published: May 2008

To understand the development of biofilms on metal surfaces, analysis of initial bacterial attachment to surfaces is crucial. Here we present the results of a study, using Shewanella oneidensis MR‐1 as a model organism, in which vertical scanning interferometry (VSI) was used to investigate the initial stages of cell attachment to glass, steel and aluminium surfaces. It was found that while VSI gave unambiguous results with opaque surfaces, when reflective surfaces were used, an artifact sometimes appeared, with the bacteria appearing as rod‐shaped pits rather than as cells on the surface. When the bacteria were altered to increase opacity, this artifact disappeared, and upon further investigation, it was found that the observational artifact was the result of a conflict between light reflected from the bacteria and the light reflected from the bacteria–metal interface. These results suggest that not only can bacteria be measured on surfaces using VSI, but with some modifications to the analytical software, there may be a unique window for studying the bacterial/substrate interface that can be used for quantitative observations. Imaging and characterization of the bacteria–substrate interface in vivo (previously invisible) will provide new insights into the interactions that occur at this important juncture.
Determinants of Food Industry Performance: Survey Data and Regressions for Denmark
Authors: Furtan W. H. , Sauer J.
Published: May 2008

This paper investigates empirically the determinants of firms’ performance in the agri‐food sector by using recent survey data for Denmark. Treating sales per employee as a proxy for value added, we estimate several bootstrapped regression models to draw conclusions on the marginal effects of potential performance determinants such as the form and nature of ownership, stage of the food chain and commodity sector, new product development, staff quality, firms’ competitive stance, and elements of firms’ strategy. To draw robust inferences we apply, besides the ordinary heteroscedasticity‐corrected Tobit maximum likelihood estimator, a non‐parametric least absolute deviations estimator (LAD/CLAD) based on a quantile regression procedure. The results indicate that we cannot reject the hypothesis of no influence of dominant orientation on value added. Rather, firms’ focus on human capital, stage and commodity sector better explains their value addition. We reject the hypothesis that regional networks have no influence on value added. Location in Århus, emphasis on human capital and the negative influence of outsourcing on value added all provide supporting evidence. We reject the hypothesis of no influence of foreign direct investment (FDI), and moreover propose that FDI has targeted the Danish domestic market as a source of value added.
Intra‐abdominal adhesion formation induces anti‐oxidative injury, enhances cell proliferation, and prevents complement‐mediated lysis
Authors: Yu Sung‐Liang , Singh Sher , Chen Huei‐Wen , Chen Hsuan‐Yu , Chen Jeremy J. W. , Chen Wen‐Jone , Chen Han‐Shiang , Chen Shyr‐Chyr
Published: May 2008

Whether the alteration of gene expression is accompanied with intra‐abdominal adhesion formation is unclear. The aim of this study was to analyze the dynamic gene expression patterns in an animal model of intra‐abdominal adhesion formation. The mRNA was extracted from the jejunums of sham control mice and jejunum‐abrading mice at 1, 3, 7, and 14 days postsurgery. The mouse cDNA microarray was used to monitor the dynamic changes of the tested genes and up‐regulated and down‐regulated genes were calculated. Quantitative real‐time RT‐PCR, and immunohistochemistry staining were used to confirm the accuracy of microarray results at RNA and protein levels. The top 100 genes with the greatest change across all studied mice groups were identified and 93 of them were correct after sequencing verification. Of the 93 genes, 74 genes were up‐regulated and 19 were down‐regulated following jejunal abrasion. Gene expressions of complement‐mediated lysis, anti‐oxidative response, and cell proliferation were significantly induced during adhesion formation. Intra‐abdominal adhesion induces several genes to eliminate overfilled complement‐mediated lysis, prevent oxidative injuries, and enhance cell proliferation. These findings may provide insights into the pathogenesis of intra‐abdominal adhesion formation and might also help to identify some new target genes for specific diagnostic tools and novel therapeutic strategies.
Expression of transforming growth factor β isoforms and their roles in tendon healing
Authors: Chan Kai‐Ming , Fu Sai‐Chuen , Wong Yim‐Ping , Hui Wun‐Chun , Cheuk Yau‐Chuk , Wong Margaret Wan‐Nar
Published: May 2008

Transforming growth factor β (TGF‐β) plays active roles in tendon healing. However, the differential effects of TGF‐β isoforms on tendon healing have not been investigated. In cultured tendon fibroblasts, we tested the effects of TGF‐β1, β2, and β3 on the mRNA levels of COL1A1 and COL3A1 by quantitative real‐time polymerase chain reaction. We also investigated the expression of TGF‐β isoforms, TGF‐β receptors, procollagen Type I and Type III in a rat model of tendon healing. We found that TGF‐β3 exhibited the highest potency in stimulating COL1A1 and COL3A1. TGF‐β1 exerted antagonistic effects to TGF‐β2 and β3. All TGF‐β isoforms and procollagen Type I were confined to the edges of the healing tendon at day 28 postinjury. Our results indicated that interaction of TGF‐β isoforms exist in the regulation of collagen synthesis in tendon fibroblasts. Their effects may be further complicated by uneven spatial distribution of TGF‐β and TGF‐β receptors in healing tendons.
Identification of differentially regulated genes in fetal wounds during regenerative repair
Authors: Colwell Amy S. , Longaker Michael T. , Peter Lorenz Hermann
Published: May 2008

During mammalian skin development, wounds heal with regeneration rather than scar. Genomic microarray analysis of fetal (scarless) and postnatal (scarring) cutaneous wounds was performed to identify genes with differential expression and possible proregenerative function. Differentially expressed genes between the scarless and scarring wound transcriptomes were identified with significance analysis of microarrays. At early time points, the fraction of genes with increased expression was greater in the fetal wounds. Conversely, as time after injury increased, the fraction of genes with increased expression in postnatal wounds increased from 0% at 1 hour to 67% at 24 hours. The fetal 1‐ and 12‐hour wound transcriptomes identified genes important in DNA transcription and repair, cell cycle regulation, protein homeostasis, and intracellular signaling. The predominant expression patterns of these genes from 1 to 24 hours predominantly revealed rapid up‐regulation, followed by declining expression at 24 hours. Fewer genes with differential expression between the fetal scarless and postnatal scarring wound transcriptomes were identified at 24 hours, most of which had greater expression in the postnatal wound. Our data suggest that multiple gene products may be necessary for the coordination of skin regeneration during wound repair in the fetus.
Imaging the electric field associated with mouse and human skin wounds
Authors: Nuccitelli Richard , Nuccitelli Pamela , Ramlatchan Samdeo , Sanger Richard , Smith Peter J.S.
Published: May 2008

We have developed a noninvasive instrument called the bioelectric field imager (BFI) for mapping the electric field between the epidermis and the stratum corneum near wounds in both mouse and human skin. Rather than touching the skin, the BFI vibrates a small metal probe with a displacement of 180 μm in air above the skin to detect the surface potential of the epidermis through capacitative coupling. Here we describe our first application of the BFI measuring the electric field between the stratum corneum and epidermis at the margin of skin wounds in mice. We measured an electric field of 177±14 (61) mV/mm immediately upon wounding and the field lines pointed away from the wound in all directions around it. Because the wound current flows immediately upon wounding, this is the first signal indicating skin damage. This electric field is generated at the outer surface of the epidermis by the outward flow of the current of injury. An equal and opposite current must flow within the multilayered epidermis to generate an intraepidermal field with the negative pole at the wound site. Because the current flowing within the multilayered epidermis is spread over a larger area, the current density and subsequent E field generated in that region is expected to be smaller than that measured by the BFI beneath the stratum corneum. The field beneath the stratum corneum typically remained in the 150–200 mV/mm range for 3 days and then began to decline over the next few days, falling to zero once wound healing was complete. The mean wound field strength decreased by 64±7% following the application of the sodium channel blocker, amiloride, to the skin near the wound and increased by 82±21% following the application of the Cl− channel activator, prostaglandin E2.
A technique to visualize wound bed microcirculation and the acute effect of negative pressure
Authors: Ichioka Shigeru , Watanabe Hiromi , Sekiya Naomi , Shibata Masahiro , Nakatsuka Takashi
Published: May 2008

Although previous studies have proved that subatmospheric pressure in vacuum assisted closure therapy increased blood flow at the wound edge, no reports have presented data on blood flow in the wound bed. This study examined a technique that visualized microcirculation of the wound bed and estimated the acute effect of negative pressure. The superficial stratum of the mouse gluteal skin was microsurgically excised preserving the subdermal vascular plexus. The preserved vessels were visualized as the wound bed microcirculation using an intravital microscope–video–computer system. Three levels of negative pressure (−125 mmHg [n=12], −500 mmHg [n=12], 0 mmHg [n=8]) were applied to the wound. Our experimental model successfully and quantitatively visualized wound bed microcirculation under negative pressure application. A negative pressure of −125 mmHg significantly increased wound bed blood flow immediately after pressure application, maintained for 1 minute after pressure release, whereas in the −500 mmHg group blood flow decreased with time and reached a statistically significant level 5 minutes after pressure application. These findings reinforce the hypothesis that enhanced blood flow in the wound bed as well as at the wound edge may contribute to the beneficial effects of certain levels of negative pressure therapy for wound perfusion.
Experience of German Red Cross blood donor services with nucleic acid testing: results of screening more than 30 million blood donations for human immunodeficiency virus‐1, hepatitis C virus, and hepatitis B virus
Authors: Hourfar Michael K. , Jork Christine , Schottstedt Volkmar , Weber‐Schehl Marijke , Brixner Veronika , Busch Michael P. , Geusendam Geert , Gubbe Knut , Mahnhardt Christina , Mayr‐Wohlfart Uschi , Pichl Lutz , Roth W. Kurt , Schmidt Michael , Seifried Erhard , Wright David J. ,   German Red Cross NAT Study Group
Published: May 2008

BACKGROUND: The risk of transfusion‐transmitted human immunodeficiency virus‐1 (HIV‐1), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections is predominantly attributable to donations given during the early stage of infection when diagnostic tests may fail. In 1997, nucleic acid amplification technique (NAT)‐testing was introduced at the German Red Cross (GRC) blood donor services to reduce this diagnostic window period (WP).

STUDY DESIGN AND METHODS: A total of 31,524,571 blood donations collected from 1997 through 2005 were screened by minipool NAT, predominantly with pool sizes of 96 donations. These donations cover approximately 80 percent of all the blood collected in Germany during that period. Based on these data, the WP risk in the GRC blood donor population was estimated by using a state‐of‐the‐art mathematic model.

RESULTS: During the observation period, 23 HCV, 7 HIV‐1, and 43 HBV NAT‐only–positive donations were detected. On the basis of these data and estimated pre‐NAT infectious WPs, the residual risk per unit transfused was estimated at 1 in 10.88 million for HCV (95% confidence interval [CI], 7.51‐19.72 million), 1 in 4.30 million for HIV‐1 (95% CI, 2.39‐21.37 million), and 1 in 360,000 for HBV (95% CI, 0.19‐3.36 million). Based on observed cases of breakthrough infections, the risk of transfusion‐related infections may be even lower.

CONCLUSION: The risk of a blood recipient becoming infected with HCV, HIV‐1, or HBV has reached an extremely low level. Introduction of individual donation testing for HCV and HIV‐1 would have a marginal effect on interception of WP donations.
The Important Role of Pulmonary Vein Carina Ablation as an Adjunct to Circumferential Pulmonary Vein Isolation
Authors: UDYAVAR AMEYA R. , CHANG SHIH‐LIN , TAI CHING‐TAI , LIN YENN‐JIANG , LO LI‐WEI , TUAN TA‐CHUAN , TSAO HSUAN‐MING , HSIEH MING‐HSIUNG , HU YU‐FENG , CHIANG SHUO‐JU , CHEN YI‐JEN , WONGCHAROEN WANWARANG , HIGA SATOSHI , UENG KWO‐CHANG , CHEN SHIH‐ANN
Published: May 2008

Objectives and Background: The success rate of achieving electrical isolation by circumferential pulmonary vein ablation (CPVA) varies from 32% to 88%. We carried out ablation at the pulmonary vein carina to evaluate the elimination rates of the pulmonary vein potentials (PVPs) after one round of CPVA had failed to eliminate all the PVPs in the patients with atrial fibrillation (AF).

Methods: Ninety‐seven patients (75 males; mean age: 50 ± 12 years; 15 with persistent AF and 82 with paroxysmal AF) who underwent catheter ablation were analyzed. All patients underwent one round of CPVA with PVP elimination as the endpoint. The electrophysiology tracings were then analyzed to look for the presence of any gaps that were subsequently targeted by radiofrequency ablation. The patients in whom the PVPs still persisted underwent ablation at the pulmonary vein carina and the success rate of the PVP elimination was studied. The patients were followed up for a mean duration of 12.9 ± 8.2 months.

Results: One hundred ninety‐four ipsilateral pulmonary veins in 97 patients were subjected to CPVA with successful elimination of the PVPs in 110 ipsilateral pulmonary veins (success rate of 56.7%). A carina ablation was carried out in the remaining 84 ipsilateral pulmonary vein pairs harboring PVPs. Elimination of the PVPs was achieved in all the remaining ipsilateral pulmonary veins after the carina ablation.

Conclusion: Considering the limited efficacy of CPVA in eliminating the PVPs, pulmonary vein carina ablation is advisable to substantially increase the PVP elimination rate.
The History of Atrial Fibrillation: The Last 100 Years
Authors: PRYSTOWSKY ERIC N.
Published: May 2008

Atrial fibrillation (AF) has had a rich history that has touched the careers of many of the great clinicians and investigators of the 20th century. More recently, there has been an explosion of research into various aspects of the mechanisms and therapy for AF, as evidenced by over 8,000 publications on AF from 2000 to 2007. A century of research and clinical observations, coupled with modern investigative technologies, has enabled modern investigators to have their own “fantastic voyage” as they travel beyond the cell borders into the ionic mechanisms responsible for AF and its many atrial perturbations. One can only imagine the satisfaction of Wenckebach, MacKenzie, and Lewis if they could see how their seeds of wisdom have grown into such sturdy ideas, or how delighted Scherf would be to learn that his ectopic focus theory for AF has been given new life.

This paper on 100 years of AF was initially prepared for presentation as the Plenary Lecture at the AFib Summit for Heart Rhythm 2007 in Denver, Colorado. I have tried to provide the reader with some of the most important observations on AF, realizing that it would be impossible to include all or even most of the major research done during this time frame. I apologize to my many colleagues whose research has helped us to understand better the clinical and basic aspects of AF, yet who could not be cited for lack of space.
Temporary Occlusion of the Great Cardiac Vein and Coronary Sinus to Facilitate Radiofrequency Catheter Ablation of the Mitral Isthmus
Authors: D'AVILA ANDRE , THIAGALINGAM ARAVINDA , FOLEY LORI , FOX MELODIE , RUSKIN JEREMY N. , REDDY VIVEK Y.
Published: May 2008

Introduction: Ablation of the mitral isthmus to achieve bidirectional conduction block is technically challenging, and incomplete block slows isthmus conduction and is often proarrhythmic. The presence of the blood pool in the coronary venous system may act as a heat‐sink, thereby attenuating transmural RF lesion formation. This porcine study tested the hypothesis that elimination of this heat‐sink effect by complete air occlusion of the coronary sinus (CS) would facilitate transmural endocardial ablation at the mitral isthmus.

Methods: This study was performed in nine pigs using a 30 mm‐long prototype linear CS balloon catheter able to occlude and displace the blood within the CS (the balloon was inflated with ∼5 cc of air). Using a 3.5 mm irrigated catheter (35 W, 30 cc/min, 1 minute lesions), two sets of mitral isthmus ablation lines were placed per animal: one with the balloon deflated (CS open) and one inflated (CS Occluded). After ablation, gross pathological analysis of the linear lesions was performed.

Results: A total of 17 ablation lines were placed: 7 with CS Occlusion, and 10 without occlusion. Despite similar biophysical characteristics of the individual lesions, lesion transmurality was consistently noted only when using the air‐filled CS balloon.

Conclusions: Temporary displacement of the venous blood pool using an air‐filled CS balloon permits transmurality of mitral isthmus ablation; this may obviate the need for ablation within the CS to achieve bidirectional mitral isthmus conduction.
State of the Art: Catheter Ablation of Atrial Fibrillation
Authors: WRIGHT MATTHEW , HAÏSSAGUERRE MICHEL , KNECHT SÉBASTIEN , MATSUO SEIICHIRO , O'NEILL MARK D. , NAULT ISABELLE , LELLOUCHE NICOLAS , HOCINI MÉLÈZE , SACHER FREDERIC , JAIS PIERRE
Published: May 2008

Curative treatment of atrial fibrillation with catheter ablation is now a legitimate option for a large number of patients. In the last decade a tremendous amount has been discovered about this fascinating arrhythmia, yet there is still much that is understood. A number of different ablation strategies have been used including pulmonary vein isolation, targeting of fractionated electrograms, compartmentalising the atria with linear lesions and various combinations and modifications of these lesion sets. The optimal ablation strategy for both paroxysmal and long‐lasting persistent atrial fibrillation is unknown. In this review the possible mechanisms underlying atrial fibrillation are examined along with the current catheter ablation techniques used in the treatment atrial fibrillation.
Early Stages of Calcium Phosphate Formation on Bioactive Borosilicate Glass in Aqueous Phosphate Solution
Authors: Li Yadong , Rahaman Mohamed N. , Bal B. Sonny , Day Delbert E. , Fu Qiang
Published: May 2008

The conversion of bioactive glass to a calcium phosphate material, typically hydroxyapatite (HA), by solution–precipitation reactions in aqueous phosphate solution, has been commonly reported. This paper describes the structural and compositional characteristics of the calcium phosphate material formed during the early‐stage conversion (<5 h) of a borosilicate glass (designated H12) in aqueous phosphate solution. Disks of H12 glass were reacted with 0.25MK2HPO4solution with a starting pH=7.0 at 37°C. The structure and composition of the product layer were characterized using thin film X‐ray diffraction, scanning electron microscopy, and Fourier transform infrared reflectance spectroscopy. For reaction times <5 h, the results indicated the formation of brushite (CaHPO4·2H2O) with coarse, plate‐like crystals. In comparison, the formation of HA with small needle‐like crystals was found at later times. This early‐stage formation of brushite has not been reported in previous studies of converting bioactive silicate and borate glasses in aqueous phosphate solution.
Pressureless Sintering of Zirconium Diboride: Particle Size and Additive Effects
Authors: Fahrenholtz William G. , Hilmas Gregory E. , Zhang Shi C. , Zhu Sumin
Published: May 2008

Zirconium diboride (ZrB2) was densified by pressureless sintering using <4‐wt% boron carbide and/or carbon as sintering aids. As‐received ZrB2with an average particle size of ∼2 μm could be sintered to ∼100% density at 1900°C using a combination of boron carbide and carbon to react with and remove the surface oxide impurities. Even though particle size reduction increased the oxygen content of the powders from ∼0.9 wt% for the as‐received powder to ∼2.0 wt%, the reduction in particle size enhanced the sinterability of the powder. Attrition‐milled ZrB2with an average particle size of <0.5 μm was sintered to nearly full density at 1850°C using either boron carbide or a combination of boride carbide and carbon. Regardless of the starting particle size, densification of ZrB2was not possible without the removal of oxygen‐based impurities on the particle surfaces by a chemical reaction.
Controlling the Oligomeric Composition of Carbon‐Fiber Precursors by Dense‐Gas Extraction
Authors: Cervo Eduardo G. , Thies Mark C. , Fathollahi Bahram
Published: May 2008

Dense‐gas extraction of M‐50 petroleum pitch with the solvent toluene was carried out in a continuous, countercurrent‐flow, packed column at temperatures from 330° to 380°C, pressures from 42 to 84 bar, and a solvent‐to‐pitch ratio of 5:1. Both one‐ and two‐column configurations were used to fractionate raw pitches into top and bottom cuts of controlled oligomeric distribution. Using matrix‐assisted laser desorption–ionization mass spectroscopy for absolute molecular weight determination, the effect of changes in pitch oligomeric distribution on both the softening point and the degree of anisotropy (i.e., isotropic–mesophase equilibrium) was established. For example, pitch fractions rich in dimer and trimer species, and with essentially all monomer removed, exhibit the anisotropic microstructure typically found in precursors for high‐performance carbon fibers.