bluuebunny/crossref_metadata_2025 huggingface dataset:
Downregulation of Renal CYP-Derived Eicosanoid Synthesis in Rats With Diet-Induced Hypertension
Authors: Wang Mong-Heng , Smith Anita , Zhou Yiqiang , Chang Hsin-Hsin , Lin Songbai , Zhao Xueying , Imig John D. , Dorrance Anne M.
Published: August 2003

The incidence of essential hypertension increases with obesity; however, the mechanisms that link obesity with hypertension are unclear. Renal cytochrome P450 (CYP)-derived eicosanoids—hydroxyeicosatetraenoic acids (HETEs), epoxyeicosatrienoic acids (EETs), and dihydroxyeicosatrienoic acids (DHETs)—have been shown to play an important role in the regulation of renal function, vascular tone, and blood pressure. The objective of this study was to examine CYP-derived eicosanoid synthesis in the different renal zones (cortex, medulla, and papilla) of rats fed a high fat diet (HF). Male Sprague-Dawley rats were fed a HF diet or regular rat chow for 10 weeks. After 10 weeks, HF rats showed significantly higher systolic blood pressure, body weight, and fat:body weight ratio. The renal ω-hydroxylase activity was decreased by 46% in cortex, 43% in medulla, and 46% in papilla of HF rats. The renal epoxygenase activity was decreased by 46% in cortex, 31% in medulla, and 56% in papilla of HF rats. Interestingly, the changes in the rate of 20-HETE and EET formation in different renal zones were consistent with the levels of expression of CYP4A and CYP2C23 proteins, respectively. Furthermore, there were no significant changes in the synthesis of these metabolites in the renal microvessels. These results demonstrate that HF diet causes the downregulation of CYP4A and CYP2C23 in renal tubules, and these proteins are responsible for renal 20-HETE and EET formation. The reduction in the synthesis of these eicosanoids may play an important role in the regulation of renal function and blood pressure in obesity-induced hypertension.
Sampling Requirements for Ambulatory Blood Pressure Monitoring in the Diagnosis of Hypertension in Pregnancy
Authors: Hermida Ramón C. , Ayala Diana E.
Published: August 2003

Previous studies on ambulatory blood pressure monitoring as a potential screening test for hypertension in pregnancy have not carefully considered sampling requirements. We have examined the impact of duration and frequency of blood pressure sampling in the reproducibility of mean values in pregnancy. We analyzed 2430 blood pressure series sampled every 20 minutes during the day and every 30 minutes at night for 48 hours every 4 weeks from the first obstetric visit until delivery in 235 normotensive and 168 hypertensive pregnant women. Blood pressure series were decimated to generate shorter series with data sampled every 1, 2, 3, or 4 hours for 48 hours, as well as at the original rate for the first day. Reproducibility of mean blood pressure as well as sensitivity and specificity in the diagnosis of hypertension were compared between the original and the decimated series. Sensitivity and specificity of the 24-hour blood pressure mean are similar for the values calculated from the original series and for those obtained from shorter profiles up to data sampled every 3 hours but reduced by 5% to 12% when diagnosis is based on data sampled at 20- to 30-minute intervals for the first 24 hours. Results also indicate that the 24-hour blood pressure mean is better reproduced with data sampled at 3-hour intervals for 48 hours than by data sampled at 20- to 30-minute intervals for 1 day only. This study demonstrates that reproducibility of mean blood pressure values is more dependent on duration of sampling than on sampling rate.
Heme Oxygenase-1 Attenuates Glucose-Mediated Cell Growth Arrest and Apoptosis in Human Microvessel Endothelial Cells
Authors: Abraham Nader G. , Kushida Taketoshi , McClung Jack , Weiss Melvin , Quan Shuo , Lafaro Rocky , Darzynkiewicz Zbigniew , Wolin Michael
Published: August 2003

Heme oxygenase-1 (HO-1) is a stress protein that has been suggested to participate in defense mechanisms against agents that may induce oxidative injury, such as heme and inflammatory molecules. Incubation of endothelial cells in a high-glucose (33 mmol/L) medium for 7 days resulted in a decrease of HO activity by 34% and a decrease in HO-1 and HO-2 proteins compared with cells exposed to low glucose (5 mmol/L) (
P
<0.05) or cells exposed to mannitol (33 mmol/L). Overexpression of HO-1 was coupled with an increase in HO activity and carbon monoxide synthesis, decreased cellular heme, and acceleration in all phases of the cell cycle (
P
<0.001). The rate of cell cycle or cell birth rate was increased by 29% (
P
<0.05) in cells overexpressing HO-1 but decreased by 23% (
P
<0.05) in cells underexpressing HO-1 compared with control cells. Exposure to high glucose significantly decreased cell-cycle progression in control cells and in cells underexpressing HO-1 but did not decrease cell-cycle progression in cells overexpressing HO-1. High glucose induced p21 and p27 in control cells but not in cells overexpressing HO-1. The addition of tin-mesoporphyrin (SnMP), an inhibitor of HO activity, reversed the HO-1–mediated decrease of p21 and p27 in cells overexpressing HO-1. These findings identify a novel effect of HO-1 on endothelial cell growth and indicate that heme metabolism and HO-1 expression regulate signaling systems in cells exposed to high glucose, which controls cell-cycle progression.
Extracellular Superoxide Dismutase Is a Major Determinant of Nitric Oxide Bioavailability
Authors: Jung Oliver , Marklund Stefan L. , Geiger Helmut , Pedrazzini Thierry , Busse Rudi , Brandes Ralf P.
Published: August 2003

The bioavailability of nitric oxide (NO) within the vascular wall is limited by superoxide anions (O
2
·−
). The relevance of extracellular superoxide dismutase (ecSOD) for the detoxification of vascular O
2
·−
is unknown. We determined the involvement of ecSOD in the control of blood pressure and endothelium-dependent responses in angiotensin II–induced hypertension and renovascular hypertension induced by the two-kidney, one-clip model in wild-type mice and mice lacking the ecSOD gene. Blood pressure was identical in sham-operated ecSOD
+/+
and ecSOD
−/−
mice. After 6 days of angiotensin II–treatment and 2 and 4 weeks after renal artery clipping, blood pressure was significantly higher in ecSOD
−/−
than ecSOD
+/+
mice. Recombinant ecSOD selectively decreased blood pressure in hypertensive ecSOD
−/−
mice, whereas ecSOD had no effect in normotensive and hypertensive ecSOD
+/+
mice. Compared with sham-operated ecSOD
+/+
mice, sham-operated ecSOD
−/−
mice exhibited attenuated acetylcholine-induced relaxations. These responses were further depressed in vessels from clipped animals. Vascular O
2
·−
, as measured by lucigenin chemiluminescence, was higher in ecSOD
−/−
compared with ecSOD
+/+
mice and was increased by clipping. The antioxidant tiron normalized relaxations in vessels from sham-operated and clipped ecSOD
−/−
, as well as from clipped ecSOD
+/+
mice. In contrast, in vivo application of ecSOD selectively enhanced endothelium-dependent relaxation in vessels from ecSOD
−/−
mice. These data reveal that endogenous ecSOD is a major antagonistic principle to vascular O
2
·−
, controlling blood pressure and vascular function in angiotensin II–dependent models of hypertension. ecSOD is expressed in such an abundance that even in situations of high oxidative stress no relative lack of enzyme activity occurs.
Plasma Membrane Calcium ATPase Overexpression in Arterial Smooth Muscle Increases Vasomotor Responsiveness and Blood Pressure
Authors: Gros Robert , Afroze Talat , You Xiao-Mang , Kabir Golam , Van Wert Ryan , Kalair Waseem , Hoque Abunasr E. , Mungrue Imran N. , Husain Mansoor
Published: August 2003

In vascular smooth muscle cells (SMCs), several mechanisms act in concert to regulate the intracellular calcium concentration [Ca
2+
]
i
, which may in turn affect vascular tone. One such mechanism is the extrusion of Ca
2+
by the plasma membrane calcium ATPase (PMCA). To address, in particular, the role of the neuronal nitric oxide synthase (nNOS)-associating isoform PMCA4b in regulating vascular tone, a doxycycline-responsive transgene for human PMCA4b was overexpressed in arterial SMCs of mice. Overexpression of hPMCA4b resulted in a 2-fold increase in total aortic PMCA4 protein expression and significant real-time RT-PCR-documented differences in the levels of endogenous mouse PMCA1, PMCA4, SERCA2, and IP3R1 gene expression in arterial SMCs. Whereas no significant difference in basal [Ca
2+
]
i
or Ca
2+
sensitivity was observed in vascular SMCs or mesenteric arteries, respectively, from hPMCA4b-overexpressing versus control mice, hPMCA4b-overexpressing mice revealed a reduced set-point and increased extent of myogenic response and heightened sensitivity to vasoconstrictors. Treatment of arteries with an nNOS inhibitor resulted in a reduced set-point and increased extent of the myogenic response in control but not hPMCA4b-overexpressing mice. Moreover, aortic SMCs from hPMCA4b-overexpressing mice exhibited reduced levels of cGMP under both basal and phenylephrine-stimulated conditions. These changes were associated with significant doxycycline-reversible elevations in blood pressure. Taken together, these data show that overexpression of hPMCA4b in arterial SMCs increases vascular reactivity and blood pressure, an effect that may be mediated in part by negative regulation of nNOS.
Transmural Electrophysiological Heterogeneities Underlying Arrhythmogenesis in Heart Failure
Authors: Akar Fadi G. , Rosenbaum David S.
Published: August 2003

Although expression of numerous ion channels is altered in heart failure (HF), mechanisms by which dysfunction at the ionic and molecular levels lead to ventricular tachyarrhythmias in HF are unknown. Previously, we found that transmural heterogeneities of repolarization play a critical role in the genesis of polymorphic ventricular tachycardia (PVT) when QT interval was prolonged in LQT2. Because QT interval is also prolonged in HF, we hypothesized that transmural heterogeneities are a mechanism of PVT in HF. Optical action potentials were measured simultaneously from cells spanning the entire transmural wall of arterially perfused canine wedge preparations. Wedges were isolated from dogs without (control, n=5) and with HF (n=8) produced by rapid ventricular pacing. In HF, action potential duration (APD) prolongation was markedly heterogeneous across the transmural wall, and was characterized by disproportionate APD prolongation of midmyocardial (M) cells. APD prolongation of M cells accounted for QT-interval prolongation, and caused significant increases (
P
<0.01) in spatial gradients of repolarization across the ventricular wall from 4.3±2.1 (control) to 12.4±3.5 ms/mm (HF). Enhanced gradients were directly responsible for development of functional conduction block, leading to PVT in 63% of HF wedges but in no controls (
P
<0.03). Moreover, intramural decremental conduction and block of the premature impulse, preceded each episode of PVT, and always occurred at the border between M-cell and subepicardial zones, where repolarization gradients were highest. Selective prolongation of APD within M cells underlies several key features of the HF phenotype, including QT-interval prolongation, transmural heterogeneity of repolarization, and susceptibility to conduction block and reentrant PVT.
Key Neuroprotective Role for Endogenous Adenosine A
1
Receptor Activation During Asphyxia in the Fetal Sheep
Authors: Hunter Christian J. , Bennet Laura , Power Gordon G. , Roelfsema Vincent , Blood Arlin B. , Quaedackers Josine S. , George Sherly , Guan Jian , Gunn Alistair J.
Published: August 2003

Background and Purpose—

The fetus is well known to be able to survive prolonged exposure to asphyxia with minimal injury compared with older animals. We and others have observed a rapid suppression of EEG intensity with the onset of asphyxia, suggesting active inhibition that may be a major neuroprotective adaptation to asphyxia. Adenosine is a key regulator of cerebral metabolism in the fetus.

Methods—

We therefore tested the hypothesis that infusion of the specific adenosine A
1
receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), given before 10 minutes of profound asphyxia in near-term fetal sheep, would prevent neural inhibition and lead to increased brain damage.

Results—

DPCPX treatment was associated with a transient rise and delayed fall in EEG activity in response to cord occlusion (n=8) in contrast with a rapid and sustained suppression of EEG activity in controls (n=8). DPCPX was also associated with an earlier and greater increase in cortical impedance, reflecting earlier onset of primary cytotoxic edema, and a significantly smaller reduction in calculated cortical heat production after the start of cord occlusion. After reperfusion, DPCPX-treated fetuses but not controls developed delayed onset of seizures, which continued for 24 hours, and sustained greater selective hippocampal, striatal, and parasagittal neuronal loss after 72-hour recovery.

Conclusions—

These data support the hypothesis that endogenous activation of the adenosine A
1
receptor during severe asphyxia mediates the initial suppression of neural activity and is an important mechanism that protects the fetal brain.
Vascular Syndromes of the Thalamus
Authors: Schmahmann Jeremy D.
Published: August 2003

Background—

This article reviews the anatomy, connections, and functions of the thalamic nuclei, their vascular supply, and the clinical syndromes that result from thalamic infarction.

Summary of Review—

Thalamic nuclei are composed of 5 major functional classes: reticular and intralaminar nuclei that subserve arousal and nociception; sensory nuclei in all major domains; effector nuclei concerned with motor function and aspects of language; associative nuclei that participate in high-level cognitive functions; and limbic nuclei concerned with mood and motivation. Vascular lesions destroy these nuclei in different combinations and produce sensorimotor and behavioral syndromes depending on which nuclei are involved. Tuberothalamic territory strokes produce impairments of arousal and orientation, learning and memory, personality, and executive function; superimposition of temporally unrelated information; and emotional facial paresis. Paramedian infarcts cause decreased arousal, particularly if the lesion is bilateral, and impaired learning and memory. Autobiographical memory impairment and executive failure result from lesions in either of these vascular territories. Language deficits result from left paramedian lesions and from left tuberothalamic lesions that include the ventrolateral nucleus. Right thalamic lesions in both these vascular territories produce visual-spatial deficits, including hemispatial neglect. Inferolateral territory strokes produce contralateral hemisensory loss, hemiparesis and hemiataxia, and pain syndromes that are more common after right thalamic lesions. Posterior choroidal lesions result in visual field deficits, variable sensory loss, weakness, dystonia, tremors, and occasionally amnesia and language impairment.

Conclusions—

These vascular syndromes reflect the reciprocal cerebral cortical-thalamic connections that have been interrupted and provide insights into the functional properties of the thalamus.
Negotiating Strangerhood: Interviews with Homeless Immigrants in Copenhagen
Authors: Järvinen Margaretha
Published: August 2003

The results from a study on homeless immigrants in Copenhagen are analysed in this article. Based on 25 life-history interviews with male immigrants living in institutions for the homeless, my focus of concern is the interviewees' self-presentations and their attempts to handle their stigmatized position. Two theoretical approaches are combined. First, the narratives are analysed as representations of the immigrants' marginalized status in their new society. Many narratives echo Bauman's (1991) descriptions of the stranger as someone constructed as a `permanent other'; someone discredited, blamed and discriminated against because he/she `threatens the natural order of things'. Second, the narratives are analysed as presentations, i.e. as the narrators' preferred interpretations of their present and past situations (Scott and Lyman, 1968). The narratives are therefore read not just as reflections of `things that actually happened' to the interviewees, but also as reflections of their strategies in handling these incidents and of their attempts to present themselves in the interviews as persons `permanently on trial', persons who are `respectable after all'.
Explaining Variation In The Success Of Extreme Right Parties In Western Europe
Authors: Golder Matt
Published: August 2003

Methodological problems associated with selection bias and interaction effects have hindered the accumulation of systematic knowledge about the factors that explain cross-national variation in the success of extreme right parties. The author uses a statistical analysis that takes account of these problems to examine the effect of electoral institutions, unemployment, and immigration on the support for these parties. The data set used in this analysis is new and spans 19 countries and 165 national elections. There are four substantive conclusions. The first is that it is important to distinguish between neofascist and populist parties on the extreme right because their fortunes depend on different factors. The second is that populist parties do better in countries where the district magnitude is larger and more seats are allocated in upper tiers. The third is that although immigration has a positive effect on populist parties irrespective of the unemployment level, unemployment only matters when immigration is high. Finally, there is evidence that the permissiveness of the electoral system mediates the effect of immigration on populist parties.
Empirical Power and Type I Error Rates for an IRT Fit Statistic that Considers the Precision of Ability Estimates
Authors: Stone Clement A.
Published: August 2003

Model-data-fit of item response theory (IRT) models is generally assessed by comparing observed performance by examinees on individual items with performance that is predicted under the chosen IRT model. However, use of traditional chi-square methods to evaluate goodness-of-fit of IRT models is not appropriate when the underlying trait/ability is estimated imprecisely (e.g., shorter assessments). This article describes a goodness-of-fit statistic that considers directly the uncertainty with which ability is estimated as well as a resampling-based hypothesis testing procedure. A simulation study was conducted to evaluate the empirical power and Type I error rates for the proposed procedure. Results of the study indicated that the procedure should be useful for evaluating goodness-of-fit of IRT models for most testing applications where uncertainty in ability estimation is an issue.
Ethnic Differences in the Measurement of Academic Self-Concept in a Sample of African American and European American College Students
Authors: Cokley Kevin , Komarraju Meera , King Aisha , Cunningham Dana , Muhammad Grace
Published: August 2003

This study examined the validity and reliability of scores on the Academic Self-Concept Scale (ASCS) in a group of 291 European American and 396 African American college students. The study compared the factor structure and scale and subscale internal consistencies for these samples to previously reported findings by Reynolds. The seven-factor solution reported by Reynolds was essentially replicated with the European American sample, whereas an eight-factor solution was found with the African American sample. Results suggest that there are important ethnic differences in the structure of academic self-concept regarding beliefs about ability, and the relationship between effort and grades.
The Effects of Nonnormality on Parametric, Nonparametric, and Model Comparison Approaches to Pairwise Comparisons
Authors: Cribbie Robert A. , Keselman H. J.
Published: August 2003

Researchers in the behavioral sciences are often interested in comparing the means of several treatment conditions on a specific dependent measure. When scores on the dependent measure are not normally distributed, researchers must make important decisions regarding the multiple comparison strategy that is implemented. Although researchers commonly rely on the potential robustness of traditional parametric test statistics (e.g., t and F), these test statistics may not be robust under all nonnormal data conditions. This article compared strategies for performing multiple comparisons with nonnormal data under various data conditions, including simultaneous violations of the assumptions of normality and variance homogeneity. The results confirmed that when variances are unequal, use of the traditional two-sample t test can result in severely biased Type I and/or Type II error rates. However, the use of Welch’s two-sample test statistic with the REGWQ procedure, with either the usual means and variances or with trimmed means and Winsorized variances, resulted in good control of Type I error rates. The Kruskal-Wallis nonparametric statistic provided good Type I error control and power when variances were equal, although Type I error rates became severely inflated when variances were unequal. Furthermore, for researchers interested in eliminating intransitive decisions or comparing potential mean configuration models, a protected model-testing procedure suggested by Dayton provided good overall results.
A Meta-Analysis of the Effects of Modifications to the Angoff Method on Cutoff Scores and Judgment Consensus
Authors: Hurtz Gregory M. , Auerbach Meredith A.
Published: August 2003

The Angoff method for setting cutoff scores on examinations has been researched extensively over the past 30 years, including investigations of several procedural modifications to the method. In the current study, the authors meta-analytically synthesized this research and evaluated the systematic effects of the most common modifications on the level of the resulting cutoff scores and the degree of consensus among judges. The authors found the following: (a) when judges use a common definition of minimally competent test-takers, this tends to increase judgment consensus; (b) when judges discuss their estimates, this tends to result in higher cutoff scores with increased consensus; and (c) when judges view normative data, this tends to systematically lower cutoff scores. In addition, the authors found an interaction effect which revealed that when judges use a common definition and later discuss their estimates, this tends to produce the highest standards on average, with the highest degree of consensus among judges. Theoretical and practical implications of these effects are discussed.
An Empirical Examination of the Construct Validity of Two Alternative Self-Control Measures
Authors: Marcus Bernd
Published: August 2003

The present study contrasts a newly developed measure of self-control as outlined in the General Theory of Crime, the Retrospective Behavioral Self-Control scale (RBS), with the most widespread measure of this construct. The RBS is based exclusively on an assessment of prior behavior with possible long-term negative consequences for the actor, whereas the latter scale is an example of attitudinal measures based on a listing of specific personality traits. By means of confirmatory factor analysis, it is demonstrated that the RBS measured the intended general factor of behavior across three samples, whereas the Grasmick et al. scale did not (only administered in one sample). In addition, the nomological net of self-control is explored by relating both instruments to a comprehensive battery of psychological tests and behavioral indicators. The RBS is included as an appendix.
Measurement of Dispositional Affect: Construct Validity and Convergence with a Circumplex Model of Affect
Authors: Huelsman Timothy J. , Furr R. Michael , Nemanick Richard C.
Published: August 2003

A circumplex model of affect has recently gained tentative acceptance by prominent researchers investigating the structure of dispositional affect. The present study examines the issue of construct validity of several existing measures of affect and their fit with the circumplex model. A traditional multitrait-multimethod matrix approach is utilized first, followed by a confirmatory factor analytic approach. These analyses demonstrate that the data collected using these four scales are characterized by generally good concurrent and discriminant validity. Furthermore, the data are in partial agreement with the proposed circumplex model of affect. Issues for the further development of the circumplex model and the use of these measures are discussed.
Testing Configural, Metric, Scalar, and Latent Mean Invariance Across Genders in Sociotropy and Autonomy Using a Non-Western Sample
Authors: Hong Sehee , Malik Mary L. , Lee Min-Kyu
Published: August 2003

The Personal Style Inventory (PSI) was developed to assess individuals’ levels of sociotropy and autonomy, two personality characteristics considered to be associated with increased vulnerability to depression. This study used the approach of latent means analysis (LMA) within the framework of structural equation modeling (SEM) to explore the factor structure and gender differences associated with the PSI in a sample of Korean undergraduates ( N = 508). Results of the confirmatory factor analysis are consistent with previous work and support the cross-cultural stability of the PSI factor structure. However, in contrast to previous research, results of the LMA showed women to have higher scores than men on sociotropy and autonomy dimensions, raising the possibility of cross-cultural differences in the interaction between these personality styles and vulnerability to depression.
Approximate Confidence Intervals for Effect Sizes
Authors: Algina James , Keselman H. J.
Published: August 2003

This article defines an approximate confidence interval for effect size in correlated (repeated measures) groups designs. The authors found that their method was much more accurate than the interval presented and acknowledged to be approximate by Bird. That is, the coverage probability over all the conditions investigated was very close to the theoretical .95 value. By contrast, Bird’s interval could have coverage probability that was substantially below .95. In addition, the authors’interval was less likely than Bird’s method to present an overly optimistic portrayal of the effect. They also examined the operating characteristics of the Bird interval for effect size in an independent groups design and found that, although it is fairly accurate in its approximation of coverage probability, the accuracy of the approximation does vary with the magnitude of the population effect size.
Patterns of Errors Made by Students with Disabilities on a Reading Test with Oral Reading Administration
Authors: Barton Karen E. , Huynh Huynh
Published: August 2003

This study focused on differences in the types of errors made by students with disabilities on a multiple choice reading test administered under oral reading accommodations. The sample was composed of students with physical, emotional, learning, and mental disabilities, as well as students with no recorded disabilities. It was first found that, for the majority of items, students in various disability groups varied slightly in their choice for the distractors. Distractors were then classified in four major categories: Diversion, Misapplication, Delimiting, and Out of Bounds. No visible relationship was found between the chosen distractors and the category of errors. Some small group differences, however, were found in the number of errors in the categories of Misapplication and Delimiting. Taken together, the study indicates that when errors are used as an extra factor in exploring the nature of proficiency, the reading construct varies only slightly across disability groups. The results indicate that it is safe to adhere the same meaning to test scores for these groups even when the test is administered under different accommodations.
Exploring the APA Fifth Edition Publication Manual’s Impact on the Analytic Preferences of Journal Editorial Board Members
Authors: Capraro Mary Margaret , Capraro Robert M.
Published: August 2003

This article explores the reporting preferences of editorial board members of the American Education Research Journal,Educational Researcher, Journal of Educational Psychology, and Journal of Counseling and Development, as regards some analytic practices now suggested in the fifth edition of the American Psychological Association Publication Manual. The findings reflect the movement of the field toward reforms in practices but some resistance toward explicating editorial mandates, even though editors at 23 journals have now done so as regards effect size reporting.
Surface Texture and the Stress Concentration Factor for FRP Components with Holes
Authors: Arola D. , McCain M. L.
Published: August 2003

The influence of hole quality on the mechanical behavior of fiber reinforced laminates was studied. Holes were introduced in tensile specimens of a graphite/epoxy (Gr/Ep) laminate using an abrasive waterjet and commercial drills (diamond coated tungsten carbide twist drills or tungsten carbide drill-reamers). The machined surfaces were characterized using contact profilometry and the surface texture was used in estimating the effective stress concentration factor (øKt). Utilizing the macroscopic stress concentration posed by the hole and øKt, the total stress concentration was estimated using the principle of superposition. The Gr/Ep specimens were then loaded in tension and acoustic emission was used to monitor the failure process. The apparent stress concentration factor (øKt(app)) of the tensile specimens was determined from the ratio of tensile strengths of coupons without holes to that of specimens with holes. Based on results from tension tests the øKt(app) at first fiber failure ranged from 2.50 to 3.40. The stress concentration factors determined from experiments were within 6% of that predicted using superposition and øKt. Although the hole quality was dependent on the method of machining and drilling, results from this study confirm previous reports that there is no correlation between the surface texture and first fiber failure or ultimate tensile strength of Fiber Reinforced Plastics (FRPs) with open holes. Holes introduced using worn diamond coated twist drills exhibited the lowest surface roughness but resulted in a significant reduction in first fiber failure strength. Results from this study indicate that surface texture and øKt cannot be used for a reliable estimate of hole quality in FRPs, especially for holes produced with worn cutting tools.
Interlaminar Damage Model for Polymer Matrix Composites
Authors: Lonetti Paolo , Zinno Raffaele , Greco Fabrizio , Barbero Ever J.
Published: August 2003

A constitutive model for fiber-reinforced composite materials with damage and unrecoverable deformation, which for the first time accounts for interlaminar damage, is presented. The formulation is based on Continuous Damage Mechanics coupled with Classical Plasticity Theory in a consistent thermodynamic framework using internal state variables. In-plane damage and novel formulation of interlaminar damage are included in order to describe the main failure modes of laminates structures. A novel implementation of the constitutive model into a finite element formulation incorporating geometric nonlinearity is presented. The model uses a small number of adjustable parameters, which are identified from available experimental data. Comparisons with experimental data for composite laminates under torsion loading are shown to validate the model for interlaminar damage. Coupled material and geometrical nonlinear analysis with simultaneous in-plane and interlaminar damage is demonstrated. The effect of warping on interlaminar damage is shown to be significant.
Armed Conflict, 1989-2002
Authors: Eriksson Mikael , Wallensteen Peter , Sollenberg Margareta
Published: August 2003

A total of 226 armed conflicts have been recorded for the years 1946-2002. Of these, 116 were active in the period 1989-2002, including 31 in 2002. There were five wars in 2002. Both numbers were the lowest for this period. Seven interstate-armed conflicts were recorded 1989-2002, of which one was still active in 2002. In 2002, a larger proportion of complex major armed conflicts were resolved, compared with new and minor armed conflicts. Although the data on armed conflict presented here suggest that there is a decline in the use of armed force, there is an increased feeling of fear and insecurity in many parts of the world because of terrorism incidents.
Analyzing Women’s Roles through Graphic Representation of Narratives
Authors: Hall Joanne M.
Published: August 2003

A 1992 triangulated international nursing study of women’s health was reported. The researchers used the perspectives of feminism and symbolic interactionism, specifically role theory. A narrative analysis was done to clarify the concept of role integration. The narrative analysis was reported in 1992, but graphic/visual techniques used in the team dialogue process of narrative analysis were not reported due to space limitations. These techniques have not been reported elsewhere and thus remain innovative. Specific steps in the method are outlined here in detail as an audit trail. The process would be useful to other qualitative researchers as an exemplar of one novel way that verbal data can be abstracted visually/graphically. Suggestions are included for aspects of narrative, in addition to roles, that could be depicted graphically in qualitative research.
Two Quantitative Approaches for Estimating Content Validity
Authors: Wynd Christine A. , Schmidt Bruce , Schaefer Michelle Atkins
Published: August 2003

Instrument content validity is often established through qualitative expert reviews, yet quantitative analysis of reviewer agreements is also advocated in the literature.Two quantitative approaches to content validity estimations were compared and contrasted using a newly developed instrument called the Osteoporosis Risk Assessment Tool (ORAT).Data obtained from a panel of eight expert judges were analyzed. A Content Validity Index (CVI) initially determined that only one item lacked interrater proportion agreement about its relevance to the instrument as a whole (CVI = 0.57). Concern that higher proportion agreement ratings might be due to random chance stimulated further analysis using a multirater kappa coefficient of agreement. An additional seven items had low kappas, ranging from 0.29 to 0.48 and indicating poor agreement among the experts. The findings supported the elimination or revision of eight items. Pros and cons to using both proportion agreement and kappa coefficient analysis are examined.
Research Note: Young People and Patterns of Time Consumption in Relation to Print Media
Authors: Raeymaeckers Karin
Published: August 2003

This article evaluates trends in young people's reading habits. In order to get a better understanding of reading habits, the article compares the results of comparative and longitudinal research with results of time budget analysis studies. In accordance with the principle of displacement, time consumption analysis confirms a relationship between television viewing time and reading time, although many variables are influential in this process. Time budget analysis also indicates that the decline in reading time has not been equal across different print media. The article presents the results of a research project that combined qualitative and quantitative research techniques to analyse the media usage of Flemish 16-to 18-year-olds. The results demonstrate that reading is influenced by many different variables, among which socializing variables are the strongest. The hypothesis that television viewing time has a negative effect on reading time has to be differentiated since the results show a different relationship between viewing time and the reading of books, magazines and newspapers respectively.
Marketing Yourself in the Competitive Job Market: An Innovative Course Preparing Undergraduates for Marketing Careers
Authors: Taylor Kimberly A.
Published: August 2003

Marketing employers increasingly value general qualities, such as effective communication, presentation, and teamwork skills, in their entry-level new hires rather than specific knowledge of the marketing function. Thus, graduating with a marketing degree might not provide an advantage over other college majors in securing a position and succeeding in a marketing career. This article describes an innovative course designed to help marketing majors increase their marketability by gaining or improving skills in the areas most desired by employers. The course development process, including a benchmark study and focus group with marketing professionals, is discussed, and survey results assessing students’reactions to the course are presented. Suggestions for successfully implementing a similar course and useful references are also provided.
Using the Voeks Method to Improve Student Learning in Principles of Marketing Classes
Authors: Hansen David E.
Published: August 2003

Inspired by the observation that most introductory marketing texts seem to contain an ever-growing list of facts and concepts, this article describes a method that helps students develop a set of study skills that will improve their learning and comprehension, as well as their grades. The method presented here is related to traditional outlining, and it takes advantage of well-known findings in memory research to sharpen students’study skills. By helping students develop a study routine based on rehearsal, chunking, and elaboration of course material, both memory and comprehension are improved. In two exploratory studies, students using the proposed method received higher test scores than those using a more conventional approach. This method is recommended for students who may not already have developed sound study skills or for those who may want to improve their knowledge of the subject as well as their grades.
Challenges and Solutions for Marketing Educators Teaching in Newly Emerging Markets
Authors: Clarke Irvine , Flaherty Theresa B.
Published: August 2003

Globalization and changes in business education have created more opportunities for marketing educators to teach in newly emerging markets (NEMs). However, differences in the backgrounds and cultures of students in these countries create new challenges for the marketing educator. Yet the extant literature reveals little guidance for the instruction of basic marketing concepts within emerging economies. In this article, the authors report on the challenges faced by marketing instructors who have experienced teaching in NEMs. Detailed feedback, gained through a focus group interview, on international experiences from a faculty is examined. General advice is offered for marketers interesting in teaching in NEMs.
Enhancing Learning Outcomes: The Effects of Instructional Technology, Learning Styles, Instructional Methods, and Student Behavior
Authors: Young Mark R. , Klemz Bruce R. , Murphy J. William
Published: August 2003

The delivery of marketing education seems to be rapidly shifting toward pedagogy rich in experiential learning and strongly supported with educational technology. This study integrates and extends previous research efforts and investigates the simultaneous effects of multiple influences of technology and nontechnology factors on learning outcomes. Responses were obtained across a marketing curriculum with technology-accustomed students. The findings suggest that the use of preferred instructional methods will enhance each of the three different measures of learning outcomes, while encouraging supportive class behaviors can increase self report performance and course grade. Regardless of the dependent outcome measure, only one of the five instructional technology variables proved significant, suggesting that in contrast to previous studies that examined technology in isolation, when analyzed relative to other learning factors, technology’s influence is secondary. Implications are discussed with practical suggestions for the classroom and direction for further investigation.
Individual Characteristics and Creativity in the Marketing Classroom: Exploratory Insights
Authors: McIntyre Faye S. , Hite Robert E. , Rickard Mary Kay
Published: August 2003

This study explores student characteristics that affect creativity skills. Students from three marketing classes were included in the study. Using the Torrance Tests of Creative Thinking, comparisons were made between students in the three marketing classes and between men and women. Executive MBA (EMBA) students scored significantly lower than both traditional and nontraditional undergraduate students on an overall Creativity Index. Gender differences appear in only one of five creativity components (elaboration), and the Creativity Index indicates no significant differences between men and women. EMBA students were exposed to creativity training during the semester, and a follow-up measure of creativity showed significant improvement in three of the five components, although the Creativity Index improvement was not statistically significant. Implications for marketing faculty and an agenda for future research are presented.
Transforming the Marketing Curriculum Using Problem-Based Learning: A Case Study
Authors: Wee Lynda Keng-Neo , Alexandria Megan , Kek Yih-Chyn , Kelley Craig A.
Published: August 2003

This article describes the experiences of the marketing faculty at Temasek Polytechnic in Singapore in their effort to help their students develop essential entry-level skills by transforming the marketing curriculum using problem-based learning. The article describes how the faculty selected the problem-based learning approach and the challenges associated with implementing it. Evidence of the success of the new curriculum also is provided.
Publications in Major Marketing Journals: An Analysis of Research Productivity of Asia-Pacific Universities
Authors: Cheng Louis T. W. , Chan Kam C. , Chan Ricky Y. K.
Published: August 2003

The authors examine the marketing research productivity of Asia-Pacific universities using a set of 20 marketing journals during 1991-2000. A weighted Journal of Marketing- equivalent page count is used to account for different font and page sizes of the journals, different lengths in articles, coauthorships, and affiliations. A total of 106 universities are evaluated. The top 3 universities are, in order, the University of NewSouth Wales, the National University of Singapore, and Hong Kong University of Science and Technology. School history does not seem to relate to research productivity. Indeed, several prominent universities are not ranked as highly as other more recently established ones. In achieving publication, the degree of research emphasis and research strategy of a university might play a more important role than years of operation. A majority of the top 20 Asia-Pacific universities have made significant progress in research output during 1991-2000.
The Impact of Voice and Justification on Students’ Perceptions of Professors’ Fairness
Authors: Schmidt Thomas A. , Houston Mark B. , Bettencourt Lance A. , Boughton Paul D.
Published: August 2003

Empirical research consistently demonstrates support for a relationship between fairness by professors and important educational outcomes. The structure of a college-level marketing course can create many situations that raise issues of justice or fairness in the minds of students. In this study, the authors examine the impact of grade outcomes and two procedures that are frequently employed in the classroom by professors—voice and justification—on students’perceptions of instructor fairness. Results of an experiment with 451 students are reported. Results suggest that voice, justification, and grade outcomes relate significantly to students’ perceptions of professor fairness (although not in the exact pattern that was predicted).
GRISLEE: Gasmain Repair and Inspection System for Live Entry Environments
Authors: Schempf Hagen , Mutschler Edward , Goltsbergm Vitaly , Crowley William
Published: August 2003

US gas companies spend over $300 million annually detecting and repairing gas leaks in urban and suburban settings. The current approach is one of above-ground leak detection and pinpointing, followed by excavation, repair and restoration. The major cost incurred is typically that of digging and restoring the excavation site. The Gas Research Institute and the National Aeronautics and Space Administration are funding a program at Carnegie Mellon University (CMU) Robotics Institute and Maurer Engineering to reduce the cost of repairing gas distribution mains using advanced remote and robotics technologies to provide up to 50% cost savings over conventional repair methods. Under this program, CMU has developed GRISLEE (Gasline Robotic Inspection System for Live Entry Environments), a coiled-tubing deployed, remotely controllable, modular leak-detection, inspection, surface-preparation and repair robot system for the real-time in situ spot repair of live 4 inch diameter distribution gas mains. The system is capable of repairing two or more leaks per day from a single excavation over a 2000 ft length under live conditions (i.e., without downtime of the gas main and thus no customer service interruption). The prototype system has undergone laboratory testing and proven the feasibility of its modular inspection, sensing, preparation, and repair technologies and systems. Field trials with multiple utilities will be carried out during late 2002.
A Semi-Autonomous Robot for Stripping Paint from Large Vessels
Authors: Ross Bill , Bares John , Fromme Chris
Published: August 2003

The National Robotics Engineering Consortium and UltraStrip Systems Inc. have developed a highly flexible and productive robot to strip paint from large ships and other large ferro-magnetic structures based on the patents obtained by UltraStrip Systems, Inc. (US patents: 6,425,340; 5,849,099; 5,628,271). Removal of corrosion and coatings from large vessels has become a serious economic and environmental problem, and current practices are becoming infeasible. The M2000 robot removes paint from ships using ultrahigh pressure water jets and recovers the water and debris in an environmentally sound way. The addition of simple, easy-to-use, cruise control features to the robot has permitted significant increases in productivity, safety, and stripping quality.
Effects of Filler Content and Hygrothermal Ageing on Compressive Properties of Fly Ash-Epoxy Composites
Authors: Kulkarni S. M. , Kishore
Published: August 2003

Compressive properties of fly ash-epoxy composites with and without exposure to warm water were studied. Ash by itself being susceptible to absorption of water the amount of fly ash was found to influence the water absorption. Composites tested under compression after two durations of exposure showed improvement in properties. Properties after longer exposure were, however, not much different from those recorded for shorter exposed test samples. The microscopic examination revealed less of debonds at the ash-epoxy interface consequent to water ingress. This is interpreted in this work to mean that ash particles absorbing water and attendant swelling could have aided in this situation which factor could also be augmented by the epoxy showing signs of volumetric expansion following ingress of water. These situations could have helped in reduction of the severity of these debonds acting as stress raisers thereby improving the compressive properties of water ingressed composites.