bluuebunny/crossref_metadata_2025 huggingface dataset:
Two Types of C Nociceptors in Human Skin and Their Behavior in Areas of Capsaicin-Induced Secondary Hyperalgesia
Authors: Serra Jordi , Campero Mario , Bostock Hugh , Ochoa José
Published: February 2004

Peripheral nociceptor sensitization is accepted as an important mechanism of cutaneous primary hyperalgesia, but secondary hyperalgesia has been attributed to central mechanisms since evidence for sensitization of primary afferents has been lacking. In this study, microneurography was used to test for changes in sensitivity of C nociceptors in the area of secondary hyperalgesia caused by intradermal injection of capsaicin in humans. Multiple C units were recruited by electrical stimulation of the skin at 0.25 Hz and were identified as discrete series of dots in raster plots of spike latencies. Nociceptors slowed progressively during repetitive stimulation at 2 Hz for 3 min. According to their response to mechanical stimulation, nociceptors could be classified as either mechano-sensitive (CM) or mechano-insensitive (CMi). These two nociceptor subtypes had different axonal properties: CMi units slowed by 2% or more when stimulated at 0.25 Hz after a 3-min pause, whereas CM units slowed by <1%. This stimulation protocol was used before capsaicin injection to identify nociceptor subtype without repeated probing, thus avoiding possible mechanical sensitization. Capsaicin, injected 10–50 mm away from the site of electrical stimulation, had no effect on any of 29 CM units, but induced bursts of activity in 11 of 15 CMi units, after delays ranging from 0.5 to 18 min. The capsaicin injections also sensitized a majority of the CMi units, so that 11 of 17 developed immediate or delayed responsiveness to mechanical stimuli. This sensitization may contribute a peripheral C fiber component to secondary hyperalgesia.
Cutaneous and Colonic Rat DRG Neurons Differ With Respect to Both Baseline and PGE2-Induced Changes in Passive and Active Electrophysiological Properties
Authors: Gold Michael S. , Traub Richard J.
Published: February 2004

This study was designed to test the hypotheses that pain syndromes associated with specific body regions reflect unique properties of sensory neurons innervating these regions and/or unique responses of these afferents to tissue damage. Acutely dissociated adult rat dorsal root ganglia (DRG) neurons retrogradely labeled from either the colon or the glabrous skin of the hindpaw were studied by whole cell patch-clamp recording in current-clamp mode. Two populations of colonic afferent neurons were studied: pelvic afferents (arising from L6, S1, and S2 DRG = LS DRG) and hypogastric/lumbar colonic afferents (arising from T13, L1, and L2 DRG = TL DRG). Passive and active electrophysiological properties were studied before and after application prostaglandin E2 (PGE2). We observed marked differences between cutaneous and colonic sensory neurons with respect to baseline passive and active electrophysiological properties as well as both the magnitude and pattern of PGE2-induced changes in excitability, passive, and active properties. There were also significant differences between TL and LS neurons with respect to baseline and PGE2-induced changes in several passive and active electrophysiological properties. Our results suggest that differences between cutaneous and colonic neurons reflect differences in pattern and/or density of ionic currents present in the plasma membrane. More interestingly, the ionic currents underlying the PGE2-induced sensitization of cutaneous neurons appeared to differ from those underlying the sensitization of colonic neurons. The implication of this observation is that it may be possible, in fact necessary, to treat pain arising from specific body regions with unique therapeutic interventions.
Differential Expression of Cardiac Biomarkers by Gender in Patients With Unstable Angina/Non–ST-Elevation Myocardial Infarction
Authors: Wiviott Stephen D. , Cannon Christopher P. , Morrow David A. , Murphy Sabina A. , Gibson C. Michael , McCabe Carolyn H. , Sabatine Marc S. , Rifai Nader , Giugliano Robert P. , DiBattiste Peter M. , Demopoulos Laura A. , Antman Elliott M. , Braunwald Eugene
Published: February 2004

Background—

Diagnosis of coronary artery disease in women is more difficult because of lower specificity of symptoms and diagnostic accuracy of noninvasive testing. We sought to examine the relationship between gender and cardiac biomarkers in patients with unstable angina (UA)/non–ST-segment elevation myocardial infarction (NSTEMI).

Methods and Results—

In the TACTICS-TIMI 18, OPUS-TIMI 16, and TIMI 11 studies, baseline samples were analyzed in the Thrombolysis In Myocardial Infarction (TIMI) biomarker core laboratory. We examined the relationship between gender and elevated biomarkers. Of 1865 patients from TACTICS-TIMI 18, 34% were women. Fewer women had elevated creatine kinase-MB or troponins, whereas more had elevated high-sensitivity C-reactive protein or brain natriuretic peptide. Presence of ST-segment deviation and TIMI risk scores were not significantly different. This pattern was confirmed in TIMI 11 and OPUS-TIMI 16. The prognostic value of the markers in TACTICS-TIMI 18 was similar in women and men. When a multimarker approach was examined, a greater proportion of high-risk women were identified. Marker-positive patients of both genders had improved outcome with an invasive strategy; however, marker-negative women appeared to have improved outcomes with a conservative strategy.

Conclusions—

In patients with UA/NSTEMI, there was a different pattern of presenting biomarkers. Men were more likely to have elevated creatine kinase-MB and troponins, whereas women were more likely to have elevated C-reactive protein and brain natriuretic peptide. This suggests that a multimarker approach may aid the initial risk assessment of UA/NSTEMI, especially in women. Further research is necessary to elucidate whether gender-related pathophysiological differences exist in presentation with acute coronary syndromes.
Clinical Correlates and Heritability of Flow-Mediated Dilation in the Community
Authors: Benjamin Emelia J. , Larson Martin G. , Keyes Michelle J. , Mitchell Gary F. , Vasan Ramachandran S. , Keaney John F. , Lehman Birgitta T. , Fan Shuxia , Osypiuk Ewa , Vita Joseph A.
Published: February 2004

Background—

Studies in selected samples have linked impaired endothelial function with cardiovascular disease and its risk factors. The clinical correlates and heritability of endothelial function in the community have not been described.

Methods and Results—

We examined a measure of endothelial function, brachial artery flow-mediated dilation (FMD), expressed as both percent (FMD%) and actual dilation by ultrasound with the occlusion cuff below the elbow in 2883 Framingham Study participants (52.9% women; mean age, 61 years). A subset of 1096 participants performed a 6-minute walk test before FMD determination. Mean FMD% was 3.3±3.0% in women and 2.4±2.4% in men. In stepwise multivariable linear regression models, FMD% was inversely related to age, systolic blood pressure, body mass index (BMI), lipid-lowering medication, and smoking, whereas it was positively related to female gender, heart rate, and prior walk test. The estimated heritability of FMD% was 0.14. FMD actual dilation findings were similar, except that female sex and BMI were not significantly associated.

Conclusions—

Increasing age, systolic blood pressure, BMI, and smoking were associated with lower FMD% in our community-based sample, whereas prior exercise and increasing heart rate were associated with higher FMD%. The estimated heritability of FMD was modest. Future research will permit more complete characterization of the genetic and environmental determinants of endothelial function and its prognostic value in the community.
Vascular Responses at Proximal and Distal Edges of Paclitaxel-Eluting Stents
Authors: Serruys Patrick W. , Degertekin Muzaffer , Tanabe Kengo , Russell Mary E. , Guagliumi Giulio , Webb John , Hamburger Jaap , Rutsch Wolfgang , Kaiser Christoph , Whitbourn Robert , Camenzind Edoardo , Meredith Ian , Reeves François , Nienaber Christoph , Benit Edouard , Disco Clemens , Koglin Jörg , Colombo Antonio
Published: February 2004

Background—

On the basis of brachytherapy experience, edge stenosis has been raised as a potential limitation for drug-eluting stents. We used serial intravascular ultrasound (IVUS) to prospectively analyze vessel responses in adjacent reference segments after implantation of polymer-controlled paclitaxel-eluting stents.

Methods and Results—

TAXUS II was a randomized, double-blind trial with 2 consecutive patient cohorts that compared slow-release (SR) and moderate-release (MR) paclitaxel-eluting stents with control bare metal stents (BMS). By protocol, all patients had postprocedure and 6-month follow-up IVUS. Quantitative IVUS analysis was performed by an independent core laboratory, blinded to treatment allocation, in 5-mm vessel segments immediately proximal and distal to the stent. Serial IVUS was available for 106 SR, 107 MR, and 214 BMS patients. For all 3 groups, a significant decrease in proximal-edge lumen area was observed at 6 months. The decrease was comparable (by ANOVA,
P
=0.194) for patients in the SR (−0.54±2.1 mm
2
) and MR (−0.88±1.9 mm
2
) groups compared with the BMS (−1.02±1.9 mm
2
) group. For the distal edge, a significant decrease in lumen area was only observed with BMS (−0.91±2.0 mm
2
,
P
<0.0001); this decrease was significantly attenuated with SR (0.08±2.0 mm
2
) and MR (−0.19±1.7 mm
2
) stents (
P
<0.0001 by ANOVA). Negative vessel remodeling was observed at the proximal (−0.48±2.2 mm
2
,
P
=0.011) but not the distal edges of BMS and at neither edge of SR or MR stents.

Conclusions—

The marked reduction in in-stent restenosis with SR or MR stents is not associated with increased edge stenosis at 6-month follow-up IVUS. In fact, compared with BMS, there is instead a significant reduction in late lumen loss at the distal edge with TAXUS stents.
Analysis of 1-Year Clinical Outcomes in the SIRIUS Trial
Authors: Holmes David R. , Leon Martin B. , Moses Jeffrey W. , Popma Jeffrey J. , Cutlip Donald , Fitzgerald Peter J. , Brown Charles , Fischell Tim , Wong Shing Chiu , Midei Mark , Snead David , Kuntz Richard E.
Published: February 2004

Background—

This study evaluated a large group of patients enrolled in a double-blind randomized trial of the sirolimus-eluting stent to document whether the initial clinical improvement seen in previous smaller series is maintained out to 12 months and to study the potential treatment effect in patient subsets known to be at increased risk of restenosis.

Methods and Results—

A total of 1058 patients with de novo native coronary stenosis undergoing clinically indicated percutaneous coronary intervention were randomly assigned to sirolimus-eluting stent (533) or control bare stent (525). Procedural success and in-hospital outcomes were excellent and did not differ between the 2 groups. At 9 months, clinical restenosis, defined as target-lesion revascularization, was 4.1% in the sirolimus limb versus 16.6% in the control limb (
P
<0.001). At 12 months, the absolute difference in target-lesion revascularization continued to increase and was 4.9% versus 20% (
P
<0.001). There were no differences in death or myocardial infarction rates. In high-risk patient subsets, defined by vessel size, lesion length, and presence of diabetes mellitus, there was a 70% to 80% reduction in clinical restenosis at 1 year.

Conclusions—

Placement of the sirolimus-eluting stent results in continued clinical improvement at 1 year after initial implantation, with significant reduction in clinical restenosis as defined by target-lesion revascularization. Between 9 and 12 months, the absolute reduction of clinical restenosis continues to increase. Even in high-risk subsets of patients, there is a 70% to 80% relative reduction in clinical restenosis at 12 months with this drug-eluting stent.
Exercise Training Enhances Vasodilation Responses to Vascular Endothelial Growth Factor in Porcine Coronary Arterioles Exposed to Chronic Coronary Occlusion
Authors: Fogarty Jennifer A. , Muller-Delp Judy M. , Delp Michael D. , Mattox Mildred L. , Laughlin M. Harold , Parker Janet L.
Published: February 2004

Background—

Chronic coronary occlusion (CCO) impairs endothelial function of distal collateral–dependent microvasculature; however, long-term exercise training (EX) seems to improve endothelial dysfunction. We hypothesized that EX enhances vasodilation responses to vascular endothelial growth factor (VEGF
165
), mediated via nitric oxide (NO), in arterioles exposed to CCO.

Methods and Results—

The proximal left circumflex coronary artery (LCx) of female Yucatan miniswine was surgically instrumented with an ameroid occluder to induce CCO; 8 weeks after surgery, animals were randomized into 14-week sedentary (SED) or EX (treadmill; 5 d/wk) protocols. Coronary arterioles (≈100 μm in diameter) were isolated from collateral-dependent (LCx) and nonoccluded (left anterior descending; LAD) perfused myocardium of SED and EX animals. Vasodilation was assessed by videomicroscopy and MacLab data acquisition. Responses to VEGF
165
were unaffected by EX in nonoccluded LAD arterioles; in contrast, EX markedly enhanced VEGF
165
-induced vasodilation of collateral-dependent LCx arterioles (
P
<0.05; EX versus SED). Furthermore, VEGF
165
-induced vasodilation of EX LCx arterioles exceeded that of EX or SED LAD arterioles (
P
<0.05). Enhanced vasodilation of EX LCx arterioles was abolished by inhibition of NO synthase and tyrosine kinase activity. Combined inhibition of NO synthase and cyclooxygenase decreased VEGF
165
-induced vasodilation of all vessels.

Conclusions—

EX enhances VEGF
165
-induced vasodilation in arterioles distal to CCO; EX effects seem to be mediated through increases in NO.
Serum Homocysteine in Relation to Mortality and Morbidity From Coronary Heart Disease
Authors: Zylberstein Dimitri Edin , Bengtsson Calle , Björkelund Cecilia , Landaas Sverre , Sundh Valter , Thelle Dag , Lissner Lauren
Published: February 2004

Background—

Elevated serum total homocysteine (tHcy) is an established risk factor for cardiovascular disease (CVD), especially in men. However, there are few prospective population studies on female cohorts, and none of these has been longer than 13 years.

Methods and Results—

The Population Study of Women in Gothenburg began in 1968/1969, at which time a representative population-based cohort of women aged 38, 46, 50, 54, and 60 years was recruited. The present cohort is a prospective follow-up of 1368 women in the original cohort for whom blood samples were stored and who were free of previous acute myocardial infarction (AMI) at the 1968/1969 baseline. Homocysteine was analyzed in 2001 with frozen serum from the baseline study and related to AMI incidence and mortality during 24 years of follow-up. Cox regression analyses were used with adjustment for age, traditional risk factors, and tHcy modifiers. For the fifth tHcy quintile, relative risk was 1.86 (95% CI 1.06 to 3.26) for AMI and 5.14 (95% CI 2.22 to 11.92) for death due to AMI. Age-standardized Kaplan-Meier plots for the fifth tHcy quintile versus others showed significant differences both for AMI and for death due to AMI that were apparent after 15 years of follow-up.

Conclusions—

Homocysteine in middle-aged women is an independent risk factor for myocardial infarction and in particular mortality due to myocardial infarction. The study illustrates that long-term prospective studies might be necessary to show effects of homocysteine levels on AMI morbidity and mortality in women.
Estrogen Plus Progestin and the Risk of Peripheral Arterial Disease
Authors: Hsia Judith , Criqui Michael H. , Rodabough Rebecca J. , Langer Robert D. , Resnick Helaine E. , Phillips Lawrence S. , Allison Matthew , Bonds Denise E. , Masaki Kamal , Caralis Panagiota , Kotchen Jane M.
Published: February 2004

Background—

Observational studies have reported less frequent carotid atherosclerosis in healthy women taking postmenopausal hormone therapy. Estrogen with progestin did not reduce peripheral arterial events among women with preexisting coronary heart disease. This analysis evaluates clinical peripheral arterial disease among generally healthy women in the Women’s Health Initiative randomized trial of estrogen plus progestin.

Methods and Results—

The Estrogen Plus Progestin trial assigned 16 608 postmenopausal women, mean age 63.3±7.1 years, to daily conjugated estrogens (0.625 mg) with medroxyprogesterone acetate (2.5 mg) or placebo and documented health outcomes over an average of 5.6 years of follow-up. Hospitalization for peripheral arterial disease was infrequent, with annualized rates of 0.08%, 0.06%, and 0.02% for carotid disease, lower extremity arterial disease, and abdominal aortic aneurysm, respectively. The incidence of peripheral arterial events did not differ between treatment groups (hazard ratio [HR] 0.89, 95% confidence interval 0.63, 1.25). The risk was slightly greater among women assigned to active estrogen with progestin in years 1 (HR 1.33) and 2 (HR 1.27), and was slightly lower in later years (HR 0.85 and 0.87 in years 5 and ≥6). Among adherent participants, the hazard ratio for peripheral arterial events was 1.23 (95% confidence interval 0.79, 1.91) over the 5.6 years of follow up. Subgroup analysis identified no significant interactions between estrogen with progestin and baseline characteristics with regard to peripheral arterial disease risk.

Conclusions—

Among generally healthy postmenopausal women, conjugated estrogens with progestin did not confer protection against peripheral arterial disease.
High Rates of Sustained Smoking Cessation in Women Hospitalized With Cardiovascular Disease
Authors: Sivarajan Froelicher Erika S. , Miller Nancy Houston , Christopherson Dianne J. , Martin Kirsten , Parker Kathleen M. , Amonetti Marcy , Lin Zhen , Sohn Min , Benowitz Neal , Taylor C.B. , Bacchetti Peter
Published: February 2004

Background—

Although men hospitalized with cardiovascular disease (CVD) show high smoking-cessation rates, similar data for women are lacking. We tested the efficacy of smoking-cessation intervention in women hospitalized for CVD.

Methods and Results—

In this randomized controlled trial conducted from 1996 to 2001, 277 women diagnosed with CVD (mean age 61±10 years) were randomly assigned within 1 of 12 San Francisco Bay Area hospitals to a usual-care group (UG; n=135) or intervention group (IG; n=142). Baseline histories were obtained, and interviews to ascertain self-reported smoking status occurred at 6, 12, 24, and 30 months after hospitalization. The UG received strong physician’s advice, a self-help pamphlet, and a list of community resources. The IG received strong physician’s advice and a nurse-managed cognitive behavioral relapse-prevention intervention at bedside, with telephone contact at intervals after discharge. The groups were similar demographically and had smoked cigarettes for a median of 38 (IG) or 40 (UG) years. Time to resumption of continuous smoking was assessed by Kaplan-Meier analysis, and risk differences between groups were determined. Time smoke-free was significantly greater for the IG than the UG (
P
=0.038). Point prevalence for nonsmoking at the interviews was somewhat greater for the IG than the UG (
P
>0.15 at all times).

Conclusions—

Cognitive behavioral intervention resulted in longer average times to resumption of smoking, but in these 2 groups of older women with limited social and financial resources, long-term success rates were similar. Systematic identification of smokers and even the brief intervention afforded the UG yielded a high smoking-cessation rate over time.
Geometrical Computations Explain Projection Patterns of Long-Range Horizontal Connections in Visual Cortex
Authors: Ben-Shahar Ohad , Zucker Steven
Published: February 2004

Neurons in primary visual cortex respond selectively to oriented stimuli such as edges and lines. The long-range horizontal connections between them are thought to facilitate contour integration. While many physiological and psychophysical findings suggest that collinear or association field models of good continuation dictate particular projection patterns of horizontal connections to guide this integration process, significant evidence of interactions inconsistent with these hypotheses is accumulating. We first show that natural random variations around the collinear and association field models cannot account for these inconsistencies, a fact that motivates the search for more principled explanations. We then develop a model of long-range projection fields that formalizes good continuation based on differential geometry. The analysis implicates curvature(s) in a fundamental way, and the resulting model explains both consistent data and apparent outliers. It quantitatively predicts the (typically ignored) spread in projection distribution, its nonmonotonic variance, and the differences found among individual neurons. Surprisingly, and for the first time, this model also indicates that texture (and shading) continuation can serve as alternative and complementary functional explanations to contour integration. Because current anatomical data support both (curve and texture) integration models equally and because both are important computationally, new testable predictions are derived to allow their differentiation and identification.
Mean Instantaneous Firing Frequency Is Always Higher Than the Firing Rate
Authors: Lánský Petr , Rodriguez Roger , Sacerdote Laura
Published: February 2004

Frequency coding is considered one of the most common coding strategies employed by neural systems. This fact leads, in experiments as well as in theoretical studies, to construction of so-called transfer functions, where the output firing frequency is plotted against the input intensity. The term firing frequency can be understood differently in different contexts. Basically, it means that the number of spikes over an interval of preselected length is counted and then divided by the length of the interval, but due to the obvious limitations, the length of observation cannot be arbitrarily long. Then firing frequency is defined as reciprocal to the mean interspike interval. In parallel, an instantaneous firing frequency can be defined as reciprocal to the length of current interspike interval, and by taking a mean of these, the definition can be extended to introduce the mean instantaneous firing frequency. All of these definitions of firing frequency are compared in an effort to contribute to a better understanding of the input-output properties of a neuron.
Kalman Filter Control Embedded into the Reinforcement Learning Framework
Authors: Szita István , Lőrincz András
Published: February 2004

There is a growing interest in using Kalman filter models in brain modeling. The question arises whether Kalman filter models can be used on-line not only for estimation but for control. The usual method of optimal control of Kalman filter makes use of off-line backward recursion, which is not satisfactory for this purpose. Here, it is shown that a slight modification of the linear-quadratic-gaussian Kalman filter model allows the on-line estimation of optimal control by using reinforcement learning and overcomes this difficulty. Moreover, the emerging learning rule for value estimation exhibits a Hebbian form, which is weighted by the error of the value estimation.
Rapid Processing and Unsupervised Learning in a Model of the Cortical Macrocolumn
Authors: Lücke Jörg , Malsburg Christoph von der
Published: February 2004

We study a model of the cortical macrocolumn consisting of a collection of inhibitorily coupled minicolumns. The proposed system overcomes several severe deficits of systems based on single neurons as cerebral functional units, notably limited robustness to damage and unrealistically large computation time. Motivated by neuroanatomical and neurophysiological findings, the utilized dynamics is based on a simple model of a spiking neuron with refractory period, fixed random excitatory interconnection within minicolumns, and instantaneous inhibition within one macrocolumn. A stability analysis of the system's dynamical equations shows that minicolumns can act as monolithic functional units for purposes of critical, fast decisions and learning. Oscillating inhibition (in the gamma frequency range) leads to a phase-coupled population rate code and high sensitivity to small imbalances in minicolumn inputs. Minicolumns are shown to be able to organize their collective inputs without supervision by Hebbian plasticity into selective receptive field shapes, thereby becoming classifiers for input patterns. Using the bars test, we critically compare our system's performance with that of others and demonstrate its ability for distributed neural coding.
Temporally Asymmetric Learning Supports Sequence Processing in Multi-Winner Self-Organizing Maps
Authors: Schulz Reiner , Reggia James A.
Published: February 2004

We examine the extent to which modified Kohonen self-organizing maps (SOMs) can learn unique representations of temporal sequences while still supporting map formation. Two biologically inspired extensions are made to traditional SOMs: selection of multiple simultaneous rather than single “winners” and the use of local intramap connections that are trained according to a temporally asymmetric Hebbian learning rule. The extended SOM is then trained with variable-length temporal sequences that are composed of phoneme feature vectors, with each sequence corresponding to the phonetic transcription of a noun. The model transforms each input sequence into a spatial representation (final activation pattern on the map). Training improves this transformation by, for example, increasing the uniqueness of the spatial representations of distinct sequences, while still retaining map formation based on input patterns. The closeness of the spatial representations of two sequences is found to correlate significantly with the sequences' similarity. The extended model presented here raises the possibility that SOMs may ultimately prove useful as visualization tools for temporal sequences and as preprocessors for sequence pattern recognition systems.
Self-Organizing Dual Coding Based on Spike-Time-Dependent Plasticity
Authors: Masuda Naoki , Aihara Kazuyuki
Published: February 2004

It has been a matter of debate how firing rates or spatiotemporal spike patterns carry information in the brain. Recent experimental and theoretical work in part showed that these codes, especially a population rate code and a synchronous code, can be dually used in a single architecture. However, we are not yet able to relate the role of firing rates and synchrony to the spatiotemporal structure of inputs and the architecture of neural networks. In this article, we examine how feedforward neural networks encode multiple input sources in the firing patterns. We apply spike-time-dependent plasticity as a fundamental mechanism to yield synaptic competition and the associated input filtering. We use the Fokker-Planck formalism to analyze the mechanism for synaptic competition in the case of multiple inputs, which underlies the formation of functional clusters in downstream layers in a self-organizing manner. Depending on the types of feedback coupling and shared connectivity, clusters are independently engaged in population rate coding or synchronous coding, or they interact to serve as input filters. Classes of dual codings and functional roles of spike-time-dependent plasticity are also discussed.
Rap's Unruly Body The Postmodern Performance of Black Male Identity on the American Stage
Authors: Saddik Annette J.
Published: February 2004

In response to the question, Does rap bear any “social message,” Ice Cube was careful to make a distinction between the occasions when rappers are “just having fun” and when they are performing a more serious “social message.” “Gansta rap” or “reality rap” are self-conscious performances of the complexities and commodifications of black male identity in America. Gangsta rap, the most theatrical style of rap, comments on the place of black masculinity in the American value system, and imagines alternative spaces where the power structures may be redefined.
The Taste of Bread My Theatrical Experiences in Lebanon
Authors: Karam Raif
Published: February 2004

Conditions in Lebanon, material and psychological, during the long years of war from 1975 to 1990 devastated the culture. Karam's very personal story is one man's attempt to make an experimental theatre in Lebanon. His work was interrupted, and the experiment—adapting traditional performance for an epoch permeated by modern technology—never had the chance to prosper or to spread beyond a few limited circles.
One Hundred Years of Nakedness in German Performance
Authors: Toepfer Karl
Published: February 2004

Nothing in theatre elevates the identity of actor over character more completely than nudity. Yet as a performance or spectacle, nudity remains a form of masking, insofar as it amplifies the desire to discover, to expose something hidden by clothing. But what happens when nudity becomes less and less containable within conventional theatre spaces and urges performers to expose the theatricality of spaces that otherwise seem imperturbably “real”? Toepfer analyzes nude performance aesthetic strategies in Germany over a 100-year period, from 1893 to 1992.
Toward a Taxonomy of Copresence
Authors: Zhao Shanyang
Published: February 2004

This paper contributes to the presence literature by explicating the meanings and subtypes of copresence.Copresence is defined here as consisting of two dimensions: copresence as mode of being with others, and copresence as sense of being with others. Mode of copresence refers to the physical conditions that structure human interaction. Six such conditions are delineated. Sense of copresence, on the other hand, refers to the subjective experience of being with others that an individual acquires in interaction. The main argument of this paper is that mode of copresence affects sense of copresence, and knowledge of how the former affects the latter will benefit copresence design.
Toward a More Robust Theory and Measure of Social Presence: Review and Suggested Criteria
Authors: Biocca Frank , Harms Chad , Burgoon Judee K.
Published: February 2004

At a time of increased social usage of net and collaborative applications, a robust and detailed theory of social presence could contribute to our understanding of social behavior in mediated environments, allow researchers to predict and measure differences among media interfaces, and guide the design of new social environments and interfaces. A broader theory of social presence can guide more valid and reliable measures. The article reviews, classifies, and critiques existing theories and measures of social presence. A set of criteria and scope conditions is proposed to help remedy limitations in past theories and measures and to provide a contribution to a more robust theory and measure of social presence.
The Effect of the Agency and Anthropomorphism on Users' Sense of Telepresence, Copresence, and Social Presence in Virtual Environments
Authors: Nowak Kristine L. , Biocca Frank
Published: February 2004

We report on an experiment that examined the influence of anthropomorphism and perceived agency on presence, copresence, and social presence in a virtual environment. The experiment varied the level of anthropomorphism of the image of interactants: high anthropomorphism, low anthropomorphism, or no image. Perceived agency was manipulated by telling the participants that the image was either an avatar controlled by a human, or an agent controlled by a computer. The results support the prediction that people respond socially to both human and computer-controlled entities, and that the existence of a virtual image increases tele-presence. Participants interacting with the less-anthropomorphic image reported more copresence and social presence than those interacting with partners represented by either no image at all or by a highly anthropomorphic image of the other, indicating that the more anthropomorphic images set up higher expectations that lead to reduced presence when these expectations were not met.
Being and Time: Judged Presence and Duration as a Function of Media Form
Authors: Waterworth J. A. , Waterworth E. L.
Published: February 2004

We briefly describe a novel immersive environment—the interactive tent—and an artistic production within it, the Illusion of Being. In this production, immersants experience a vivid cycle of the elements in a way that depends on their bodily movements. This elemental “story” has four versions in all, with each created to have differential effects on sense of presence and of subjective duration, according to a theoretical model. The model proposes three orthogonal dimensions of experience: focus, the level of abstraction;locus, real versus virtual; andsensus, the overall level of attention of the observer. An experiment, conducted to assess the effects of the different versions, is reported. The results confirmed the model's prediction that rated presence is relatively high when experienced media is of a form that elicits predominantly concrete (perceptual) processing, and relatively low when the emphasis is on more-abstract (conceptual) processing. But the concrete-abstract dimension had no direct effect on judged duration, contrary to our predictions. However, some evidence suggests that judged presence and estimated duration were positively correlated for media categorized as virtual, but not for content captured from the real world.
Presence Equation: An Investigation into Cognitive Factors Underlying Presence
Authors: Sas Corina , O'Hare Gregory M. P.
Published: February 2004

The relationship between presence and cognitive factors such as absorption, creative imagination, empathy, and will ingness to experience presence was investigated. Presence was defined, operationalized, and measured using a ques tionnaire that we devised. Absorption and creative imagina tion were measured using questionnaires developed in the area of hypnosis, and empathy was assessed through an interpersonal reactivity index. Results indicated significant correlations between presence and each cognitive factor. They showed that persons who are highly fantasy prone, more empathic, more absorbed, more creative, or more willing to be transported to the virtual world experienced a greater sense of presence. Regression analysis led to a pres ence equation, which could be used to predict presence based on the investigated cognitive factors. Findings are congruent with user characteristics presented by the pres ence literature and support the position that individual dif ferences are important for the study of presence.
A Dangerous Miscalculation: New Evidence from Communist-Bloc Archives about North Korea and the Crises of 1968
Authors: Lerner Mitchell
Published: February 2004

When North Korean forces seized an American intelligence ship, the USS Pueblo, in international waters on 23 January 1968, U.S. officials assumed that the attack had been orchestrated in conjunction with the Soviet Union, Communist China, or both. Based on this assumption, the Johnson administration contacted Soviet leaders and asked them to resolve the matter. But it turned out that Moscow could do little. Newly available documentation shows that North Korea was acting independently in 1968 and did not even inform Soviet or Chinese leaders in advance of the capture of the ship. The U.S. government's failure to recognize that North Korea had been acting on its own meant that a good deal of time was squandered on efforts to prod the Soviet authorities to intervene. The resolution of the prolonged crisis, in December 1968, was feasible only because the Johnson administration managed to accommodate North Korea's rather bizarre demands without yielding on the substance of the matter.
Georges Marchais and the Decline of French Communism
Authors: Vanke Jeffrey
Published: February 2004

Georges Marchais's long tenure as the leader of the French Communist Party (PCF) witnessed a sharp decline in the party's electoral performance. Shortly after Marchais took over, the PCF received more than 20 percent of the vote in parliamentary elections. By the time he left office, the party's share of the vote had dropped to less than 10 percent. A new biography of Marchais, by Thomas Hofnung, provides a nuanced assessment of the French Communist leader, showing why Marchais's political instincts, which once proved so remarkably effective, began to fail him the longer he was in power. Marchais's decision to endorse the Soviet invasion of Afghanistan in 1979—1980 symbolized the decline of the PCF, but even then Marchais's colleagues were unwilling to remove him. He remained in office for another decade, as the fortunes of the party continued to ebb. Hofnung's perceptive book takes due account of Marchais's strengths but is especially illuminating in its portrayal of the French Communists in decline a decline that paralleled the waning of the Cold War.
The Effects of Information Technology Achievement and Diffusion on Foreign Direct Investment
Authors: Gani Azmat , Sharma Basu
Published: February 2004

Foreign direct investment (FDI) and the new information and communications technology (ICT) have gained significant grounds in many parts of the world in somewhat parallel fashion. The objective of this paper is to assess the proposition that the level of technological achievement and diffusion is a determining factor in attracting FDI in high-income countries. A sample of technologically advanced countries was chosen on the basis of the technological achievement index (TAI). Crosscountry data for the period of 1994 to 1998 were used to estimate a fixed effects model. The empirical results obtained provide strong evidence that technology diffusion of new instruments of ICT, such as mobile phones and Internet hosts, are major pull factors of FDI. The results also provide evidence that robust economic environment, low unit cost, and high degree of openness are other essential determinants of FDI. We conclude that in order to retain and attract FDI, countries should create opportunities for useful innovations to be created and diffused, as well as maintain flexible, competitive and dynamic economic environments. The main policy implication for countries lagging in terms of attracting foreign investment is to build on reforms that emphasize creation and diffusion of ideas and products, as well as maintain a high degree of openness to new investors, especially in ICT.
The Impact of Unequal Access to the Internet on Earnings: A Cross-Sectional Analysis
Authors: Kim Sangmoon
Published: February 2004

The computer has transformed the way that information is spread, as well as the way that it is processed and generated. The Internet provides a huge amount of information in a cost-efficient way, and has become a main channel for gaining information. This study addresses an economic consequence of the rapid spread of information via the Internet. Given that economic rationality and utility maximization rely on agents' information set, the access to the Internet may result in information asymmetry between users and non-users, which affects utility maximization. Analyzing the CPS data, this study finds that, controlling for occupational status, education, and other variables, Internet access influences one's utility maximization, measured as hourly earnings. More specifically, information-seeking activity, but not Internet access itself, produces differences in earnings. It is also found that the characteristics of Internet users correlate with the main factors of stratification, such as race/ethnicity, education, and occupation. This finding implies that information revolution, informatization, or the information society, whatever one calls it, follows a long prevailing split between haves and have-nots, and may have exacerbated old inequalities in new ways.
Economic Reform, Discontinuous Change and China's Future
Authors: Mushkat Miron
Published: February 2004

The Chinese economy has undergone a significant transformation in the last quarter of a century. The restructuring of economic institutions has attracted considerable academic attention and has spawned a substantial number of scholarly investigations. The voluminous literature that has emerged nevertheless contains some fundamental gaps and is not entirely balanced. Some recent studies have challenged the assumptions upon which the entire edifice rests and have painted a far more cautious picture of the economy and political system in the coming years. This picture, in turn, needs to be extended, refined and, if possible, at least partially validated.
Plunder, Predation and Profiteering: The Political Economy of Armed Conflicts and Economic Violence in Modern Africa
Authors: Orogun Paul
Published: February 2004

This paper presents a comparative analytical study that is based on a political economy perspective concerning the effects of economic violence and the specter of predation-induced armed conflicts in modern African states. Although "blood diamonds," crude oil, "conflict timber," and illicit arms trafficking have engendered and exacerbated civil wars, cross-border raids, and protracted regional destabilization in Angola and the Democratic Republic of Congo, my primary focus is on the ongoing military debacle in Liberia and the recently concluded mayhem in Sierra Leone. The "resource curse" hypothesis will be utilized to examine and to illuminate the impact of economic pillaging, illicit arms trade, and predatory warlordism on the political instability and humanitarian atrocities in these two West African countries. A review of the internal regime types and the regional security relations within the sub-region will help to contextualize the recurrent trends and discernable systemic patterns that have been associated with these pillaging wars in the post-cold war era of Africa's international relations. In short, armed conflicts have weakened state capabilities, strained the financial resources of nongovernmental organizations and even raised provocative questions about the political will and sustaining capacities of the international community and regional security organizations to keep the peace and create conditions that are conducive to long-term, sustainable and viable political stability and economic development in the conflict-ridden and war-ravaged Sub-Saharan African States.
Zileuton induces hemoglobin F synthesis in erythroid progenitors: role of the l-arginine–nitric oxide signaling pathway
Authors: Haynes Johnson , Baliga B. Surendra , Obiako Boniface , Ofori-Acquah Solomon , Pace Betty
Published: February 2004

Induction of fetal hemoglobin (Hb F) is an important therapeutic tool in ameliorating complications of sickle cell disease. Nitric oxide has been implicated in the mechanism of Hb F synthesis induced by hydroxyurea (HU). This study examined whether zileuton (ZL), a structural analog of hydroxyurea, possessed Hb F–inducing properties and the potential role nitric oxide plays. ZL caused a dose-dependent increase in γ-globin expression in K562 cells. This effect was confirmed by a dose-dependent increase in Hb F synthesis in erythroid progenitors from individuals with sickle cell anemia and normal hemoglobin genotypes. l-arginine had no effect on Hb F production; however, it dose-dependently inhibited ZL's ability to induce Hb F. The nitric oxide synthase inhibitor NG-monomethyl–l-arginine (l-NMMA) inhibited l-arginine's effect and restored ZL-mediated increase in Hb F synthesis. In addition, 8-PCPT–cGMP (8-(4-chlorophenylthio)guanosine 3′,5′-cyclic monophosphate) inhibited ZL-mediated induction of Hb F synthesis. When comparing l-NMMA effects alone on ZL and HU, a partial reversal of increased Hb F synthesis was seen only with HU. Neither l-arginine alone nor l-arginine in combination with l-NMMA effected hydroxyurea-mediated induction of Hb F synthesis. This study demonstrates that ZL induces Hb F through a mechanism that involves l-arginine/nitric oxide/cGMP in a manner distinctly different from HU.
Limiting Time for Responding Enhances Behavior Corresponding to the Merits of Compliance Appeals: Refutations of Heuristic‐Cue Theory in Service and Consumer Settings
Authors: Brannon Laura A. , Brock Timothy C.
Published: February 2004

Scarcity has been widely assumed (e.g., Cialdini, 1993) to function as a cue and thereby hinder evaluative scrutiny of compliance‐gaining requests (appeals). In contrast, liberalized commodity theory (Brock & Brannon, 1992) postulated that scarcity should augment evaluative scrutiny of requests and thereby enhance behavioral correspondence to the merits of requests. In natural‐setting tests, 143 telephone operators and 305 fast‐food customers complied more with a request in response to strong than to weak reasons and did so especially when the request was accompanied by scarcity information, operationalized as a time restriction on responding. Thus, restriction did not function as a cue. Rather, in both service and consumer settings, scarcity enhanced behavior that corresponded to the merits of requests. Compliance theorists and practitioners should reconsider the cue claim for compliance appeals and should weigh the implications of bidirectional responding to compliance appeals.
Goal‐Derived Categories: The Role of Personal and Situational Goals in Category Representations
Authors: Ratneshwar S. , Barsalou Lawrence W. , Pechmann Cornelia , Moore Melissa
Published: February 2004

Prior research often emphasized a stimulus‐based or bottom‐up view of product category representations. In contrast, we emphasize a more purposeful, top‐down perspective and examine categories that consumers might construct in the service of salient (i.e., highly accessible) goals. Specifically, we investigate how the point of view imposed by salient consumer goals might affect category representations assessed by participants’ similarity judgments of food products. A key factor in our study is that we examine both individual and situational sources of variability in goal salience. In addition, we also vary the surface‐level, visual resemblance of the stimulus pairs of foods used in the study. The results suggest that personal goals (e.g., health) and situational goals (e.g., convenience) act in conjunction and exert a systematic impact on category representations. Both types of goals, when salient, enhanced the perceived similarity of goal‐appropriate products and reduced the similarity of product pairs when only one product was ideal for the particular goal. The similarity‐enhancing effect was most pronounced when the surface resemblance between the products was low, and the similarity‐diminishing effect was more apparent when surface resemblance was high. Implications are discussed for current theoretical assumptions regarding categorization in consumer research.