bluuebunny/crossref_metadata_2025 huggingface dataset:
Computer-Assisted Self-Interviewing Tailored for Special Populations and Topics
Authors: De Leeuw Edith , Hox Joop , Kef Sabina
Published: August 2003

Self-administered questionnaires have many advantages, especially when sensitive questions are asked. However, self-administered paper questionnaires have a serious drawback: Only relatively simple questionnaires can be used. Computer-assisted self-interviewing (CASI) can overcome these problems. CASI can be part of a personal interview in which the interviewer hands the computer over to the respondent for specific questions. It also can be a computerized version of the disk-by-mail survey. The authors have used both forms with very special populations (primary school children, visually impaired young adults, and parents and children from multiproblem families, in which professional guidance for the family was sought). This article introduces CASI and reviews its advantages and disadvantages, giving special attention to data quality.
Illuminating Spaces: Relational Spaces, Complicity, and Multisited Ethnography
Authors: Gustavson Leif C. , Cytrynbaum Joseph D.
Published: August 2003

This article explores the perennial issue of social relations in ethnography. The authors argue for ethnographers to attend to and wrestle with what they describe as “relational spaces” during all phases of the research by considering these relational spaces as objects of study in and of themselves. De Certeau provided the theoretical foundation for their focus on the relational spaces of ethnography with his distinction between space and place. Using ethnographic essays from their own research with youth, the authors discuss how they engage with relational spaces, both intellectually and in practice, to deepen and build on Marcus's call for recognizing complicity in relation to multisited ethnography.
Kette regulates actin dynamics and genetically interacts with Wave and Wasp
Authors: Bogdan Sven , Klämbt Christian
Published: August 2003

During development of the Drosophila nervous system, kette is required for axonal growth and pathfinding. It encodes a highly conserved homolog of the Nck-associated protein 1 (NAP1) that genetically interacts with the Drosophila homolog of Nck, dock. We show that in vivo as well as in tissue culture models most of the Kette protein is found in the cytoplasm where it colocalizes with F-actin to which it can bind via its N-terminal domain. Some Kette protein is localized at the membrane and accumulates at focal contact sites. Loss of Kette protein results in the accumulation of cytosolic F-actin. The kette mutant phenotype can be suppressed by reducing the wave gene dose, demonstrating that kette antagonizes wave function. Overexpression of the wild-type Kette protein does not interfere with normal development, whereas expression of an activated,membrane-tethered Kette protein induces the formation of large F-actin bundles in both, tissue culture cells and in vivo. This gain-of-function phenotype is independent of wave but can be suppressed by reducing the wasp gene dose, indicating that Kette is able to regulate Wasp, to which it is linked via the Abelson interactor (Abi). Our data suggest a model where Kette fulfils a novel role in regulating F-actin organization by antagonizing Wave and activating Wasp-dependent actin polymerization.
Distance function based algorithm for spatial straightness evaluation
Authors: Zhu L-M , Ding H , Xiong Y-L
Published: August 2003

This paper focuses on the development of an efficient algorithm for evaluating the spatial straightness error based on the minimum circumscribed cylinder (MCC). A signed point-surface distance function is defined, and its increment with respect to the differential motion of the surface is derived. On this basis, spatial straightness evaluation is formulated as a non-linear constrained optimization problem, and a sequential approximation algorithm, with the magnitude of the differential motion of the reference axis being well controlled at each iteration, is developed to solve it. Also, a simple approach for verification of the optimality of the solution is presented. compared with existing algorithms, it has the advantages of implementational simplicity, computational efficiency and robustness. Examples confirm the validity of the proposed algorithm.
Modeling ionic hydrogels swelling: Characterization of the non‐steady state
Authors: Traitel Tamar , Kost Joseph , Lapidot Smadar A.
Published: August 2003

Ionic hydrogels can be used as controlled release systems that respond to an external substrate or trigger by swelling or de‐swelling. One example is a glucose‐sensitive system for insulin‐controlled release based on pH‐sensitive hydrogel. To enhance understanding of non‐steady state swelling, and to facilitate design of specifications (e.g., glucose‐sensitivity) of the pH‐sensitive ionic hydrogel based on the copolymer poly (2‐hydroxyethyl methacrylate‐co‐N, N‐dimethylaminoethyl methacrylate) (poly (HEMA‐co‐DMAEMA)), we developed a mathematical compartmental model using the software SAAM II. Current analytical and computational methods focus on equilibrium swelling of hydrogels; although for many stimuli‐responsive hydrogel applications, the dynamic process is significant. We now report, using a combination of experimental data and kinetic analysis that in the poly (HEMA‐co‐DMAEMA) the rate of proton entry is governed by a different rate coefficient than water entry rate. The transport coefficient governing water uptake is dependent upon three variables: pH of external media, amine groups incorporated into the polymer, and crosslinking density of the polymer. An additional result is that swelling equilibrium is reached when all the amine groups are protonated. In this study we also demonstrate the predictive capability of the model for both interpolated and extrapolated data, and its use in design of future bench experiments. Uncovering these fundamental properties of pH‐sensitive hydrogels with the aid of a kinetic model suggests that the complexities of hydrogel research and development can be overcome by combining experimental and computational approaches. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 20–28, 2003.
Site‐specific recombination in human cells catalyzed by the wild‐type integrase protein of coliphage HK022
Authors: Kolot Mikhail , Meroz Adi , Yagil Ezra
Published: August 2003

The activity of the Integrase (Int) protein encoded by coliphage HK022 was tested in a human cell culture. Plasmids were constructed as substrates that carry the sites of the integration reaction (attP and attB) or the sites of excision (attL and attR). The site‐specific recombination reactions were monitored in cis and in trans configurations by the expression of the green fluorescent protein (GFP) as a reporter. Cells cotransfected with the substrate plasmid(s) and with a plasmid that expresses the wild‐type Int show efficient integration as well as excision in both configurations. The wild‐type Int was active in the human cells without the need to supply the accessory proteins integration host factor (IHF) and excisionase (Xis) that are indispensable for the reaction in the bacterial host. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 56–60, 2003.
Production of recombinant proteins using multiple‐copy gene integration in high‐cell‐density fermentations of Ralstonia eutropha
Authors: Srinivasan Sriram , Barnard Gavin C. , Gerngross Tillman U.
Published: August 2003

We have previously reported the development of a novel protein expression system based on Ralstonia eutropha. In this study we report on the influence of gene copynumber on recombinant protein expression in R. eutropha. We compare recombinant gene stability and expression levels of chromosomal integration with a plasmid‐based expression system. Single, double, and triple copies of a gene encoding organophosphohydrolase (OPH), an enzyme prone to inclusion‐body formation in E. coli, were integrated into the R. eutropha chromosome. A linear increase between the concentration of soluble, active OPH and gene copynumber was found. Using a triple‐copy integrant, we were able to produce approximately 4.3 g/L of OPH in a high‐cell‐density fermentation. This represents the highest titer reported to date for this enzyme, and is approximately 30 times greater than expression levels reported in E. coli. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 84: 114–120, 2003.
Neandertals, competition, and the origin of modern human behavior in the Levant
Authors: Shea John J.
Published: August 2003

The East Mediterranean Levant is a small region, but its paleoanthropological record looms large in debates about the origin of modern humans and the fate of the Neandertals. For most of the twentieth century, the Levantine paleoanthropological record supported models of continuity and evolutionary transition between Neandertals and early modern humans. Recent advances in radiometric dating have challenged these models by reversing the chronological relationship between Levantine Neandertals and early modern humans. This revised chronostratigraphy for Levantine Middle Paleolithic human fossils raises interesting questions about the evolutionary relationship between Neandertals and early modern humans. A reconsideration of this relationship moves us closer to understanding the long delay between the origin of morphologically modern‐looking humans during the Middle Paleolithic (>130 Kyr) and the adaptive radiation of modern humans into Eurasia around the time of the transition from the Middle to Upper Paleolithic (50 to 30 Kyr).
Governance in a period of strategic change in U.S. healthcare
Authors: Weil Thomas P.
Published: August 2003

The increased enrollment in managed care plans, merger mania and the development of politically and financially powerful integrated delivery systems have significantly complicated the governance of U.S. healthcare organizations. These modifications in fiscal incentives and the corporate restructuring undertaken by American health organizations has resulted in limited fiscal savings or improvements in access to care. As a result, trustees are now faced with divesting their losers, and shuttering facilities and services to reduce fixed costs. Decision‐making by trustees will be further thwarted in the future by: their institutions being forced to deliver more care without a proportional increase in revenues; physicians seeking to obtain more ambulatory revenues at a hospital's expense; the inability to adequately finance mental health and long‐term care services except among the wealthy; the number of divestitures increasing so that eventually the organizational focus for most IDSs will once again be on regionally oriented hospital systems; and much more difficulty being experienced in attracting sufficiently qualified personnel to deliver high quality health services. Finally, many of these findings relevant to the United States also are being shared by governing boards in Canada, Germany, The Netherlands and the United Kingdom. Copyright © 2003 John Wiley & Sons, Ltd.
Assessment of the quantitative and qualitative buffer function of an alluvial wetland: hydrological modelling of a large floodplain (Garonne River, France)
Authors: Weng P. , Sánchez‐Pérez J. M. , Sauvage S. , Vervier P. , Giraud F.
Published: August 2003

For 2 years, water flow‐patterns in the Garonne floodplain of south‐western France were studied in the field and through hydrodynamic modelling (MARTHE Hydrodynamic Software developed by BRGM). Water flow‐paths and the transport of dissolved elements between river and aquifer have been investigated and modelled. In order to quantify the buffer function of the alluvial floodplain, we focused our work on the effect of a major flood on the water flow‐direction, and on nitrate transport. Thus, we showed that the effect of a large flood in the river was rapidly lost with increasing distance from the river. During the observation period, a hydrologically active strip only 300 m wide on either side of the riverbed played a buffering role in absorbing the flood crest. It was also found that meanders favour the exchange between river and alluvial aquifer, shown by the creation of bypasses between the upstream and downstream parts of meanders. This, in turn, contributes to a dilution of nitrates in the phreatic aquifer, which here has higher nitrate content than the surface water; such dilution may result in an overestimation of the denitrification process in the wooded riverbanks. The coupling of chemical measurements—especially of chlorides and nitrate—with modelling of the dissolved‐element transport allows us to establish the water balance for the riparian wetland, and to separate the effect of dilution and denitrification on nitrate concentration. This indicated the existence of areas in the riparian wetlands where denitrification is particularly strong, leading to reductions in nitrate concentrations of 10 to 30 mg/l NO3− during the flood. Copyright © 2003 John Wiley & Sons, Ltd.
Using a low‐voltage intermodulation distortion sweet‐spot for controlling gain in HEMT amplifiers
Authors: Malaver Emigdio , García José Ángel , Tazón Antonio , Mediavilla Angel
Published: August 2003

In this paper, a low‐voltage high‐linearity sweet‐spot, associated with an adjustable transconductance, is proposed for implementing a simple and highly linear HEMT‐based gain control strategy. The proposed approach, based on a selective gate and drain biasing technique, is compared with the conventional solution under two‐tone and multitone excitations. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 67–70, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11129
Spectral study of a new dihydroisocoumarin
Authors: Wang H. M. , Shi W. , Xu Y. K. , Liu Y. , Lü M. J. , Pan J. Q.
Published: August 2003

A novel dihydroisocoumarin, 3,4‐dihydro‐6,8‐dihydroxy‐3‐(2′‐acetyl‐3′‐hydroxy‐5′‐methoxy)methyl‐1H‐[2]benzopyran‐1‐one, was isolated from the chloroform extract of the sap of the traditional herb Aloe vera. Its structure was determined by high‐resolution negative fast atom bombardment mass spectrometry (MS), 2D NMR spectroscopy and x‐ray crystallography. The molecular structure was elucidated by 2D NMR analysis. The complete assignment of the 1H and 13C NMR spectra of this compound was performed by using 1H detected one‐bond heteronuclear multiple quantum correlation (HMQC) and long‐range (two and three bonds) heteronuclear multiple quantum bond correlation (HMBC) experiments. Detailed analyses of the one‐ and two‐dimensional NMR techniques are presented in additional to the spectral properties (MS, IR and UV). Copyright © 2003 John Wiley & Sons, Ltd.
1H and 13C NMR assignments of abietane diterpenes from Aegiphila lhotzkyana
Authors: Pinheiro Barros Maria Claudia , Sousa Lima Mary Anne , Braz‐Filho Raimundo , Rocha Silveira Edilberto
Published: August 2003

An NMR study of one new and several known abietane diterpenes isolated from the roots of Aegiphila lhotzkyana is described. In addition to 1D NMR, several 2D shift‐correlated NMR pulse sequences (1H–1H‐COSY, NOESY, HMQC and HMBC) were used to establish all the structures, and unambiguously perform the 1H and 13C chemical shift assignments of the new natural diterpene and three derivatives, the NMR data for which have not been reported previously. Revision of current data assignment for teuvincenone H is also suggested. Copyright © 2003 John Wiley & Sons, Ltd.
Congenital pulmonary capillary hemangiomatosis: Report of two cases and review of the literature
Authors: Oviedo Angelica , Abramson Lisa P. , Worthington Ross , Dainauskas John R. , Crawford Susan E.
Published: August 2003

Pulmonary capillary hemangiomatosis (PCH) is a rare disease characterized by pulmonary hypertension and excessive neovascularization within the pulmonary interstitium, vasculature, and airways. We describe two unusual cases of congenital PCH. Both cases had concurrent anomalies, including renal and urinary bladder agenesis and hypertropic cardiomyopathy. In one case, capillary proliferation caused significant impingement of the proximal bronchial airways. A review of the current literature is described. Pediatr Pulmonol. 2003; 36:253–256. © 2003 Wiley‐Liss, Inc.
Identification of functionally conserved residues with the use of entropy–variability plots
Authors: Oliveira Laerte , Paiva Paulo B. , Paiva Antonio C.M. , Vriend Gerrit
Published: August 2003

We introduce sequence entropy–variability plots as a method of analyzing families of protein sequences, and demonstrate this for three well‐known sequence families: globins, ras‐like proteins, and serine‐proteases. The location of an aligned residue position in the entropy–variability plot correlates with structural characteristics, and with known facts about the roles of individual amino acids in the function of these proteins. The large numbers of known sequences in these families allowed us to introduce new filtering methods for variability patterns. The results are discussed in terms of a simple evolutionary model for functional proteins. Proteins 2003;52:544–552. © 2003 Wiley‐Liss, Inc.
Overexpression of a stress‐inducible aldehyde dehydrogenase gene from Arabidopsis thaliana in transgenic plants improves stress tolerance
Authors: Sunkar Ramanjulu , Bartels Dorothea , Kirch Hans‐Hubert
Published: August 2003

In plants, oxidative stress is one of the major causes of damage as a result of various environmental stresses. Oxidative stress is primarily because of the excessive accumulation of reactive oxygen species (ROS). The amplification of ROS damage is further stimulated by the accumulation of toxic degradation products, i.e. aldehydes, arising from reactions of ROS with lipids and proteins. Previously, the isolation of dehydration‐inducible genes encoding aldehyde dehydrogenases (ALDHs) was reported from the desiccation‐tolerant plant Craterostigma plantagineum and Arabidopsis thaliana. ALDHs belong to a family of NAD(P)+‐dependent enzymes with a broad substrate specificity that catalyze the oxidation of various toxic aldehydes to carboxylic acids. Analysis of transcript accumulation revealed that Ath‐ALDH3 is induced in response to NaCl, heavy metals (Cu2+ and Cd2+), and chemicals that induce oxidative stress (methyl viologen (MV) and H2O2). To investigate the physiological role and possible involvement of ALDHs in stress protection, we generated transgenic Arabidopsis plants overexpressing Ath‐ALDH3. Transgenic lines show improved tolerance when exposed to dehydration, NaCl, heavy metals (Cu2+ and Cd2+), MV, and H2O2. Tolerance of transgenic plants is correlated with decreased accumulation of lipid peroxidation‐derived reactive aldehydes (as measured by malondialdehyde) compared to wild‐type plants. Increased activity of Ath‐ALDH3 appears to constitute a detoxification mechanism that limits aldehyde accumulation and oxidative stress, thus revealing a novel pathway of detoxification in plants. We suggest that Ath‐ALDH3 could be used to obtain plants with tolerance to diverse environmental stresses.
Thermally induced conformational changes in horseradish peroxidase
Authors: Pina David G. , Shnyrova Anna V. , Gavilanes Francisco , Rodríguez Anabel , Leal Fernando , Roig Manuel G. , Sakharov Ivan Y. , Zhadan Galina G. , Villar Enrique , Shnyrov Valery L.
Published: August 2003

Detailed differential scanning calorimetry (DSC), steady‐state tryptophan fluorescence and far‐UV and visible CD studies, together with enzymatic assays, were carried out to monitor the thermal denaturation of horseradish peroxidase isoenzyme c (HRPc) at pH 3.0. The spectral parameters were complementary to the highly sensitive but integral method of DSC. Thus, changes in far‐UV CD corresponded to changes in the overall secondary structure of the enzyme, while that in the Soret region, as well as changes in intrinsic tryptophan fluorescence emission, corresponded to changes in the tertiary structure of the enzyme. The results, supported by data about changes in enzymatic activity with temperature, show that thermally induced transitions for peroxidase are irreversible and strongly dependent upon the scan rate, suggesting that denaturation is under kinetic control. It is shown that the process of HRPc denaturation can be interpreted with sufficient accuracy in terms of the simple kinetic scheme

image

where k is a first‐order kinetic constant that changes with temperature, as given by the Arrhenius equation; N is the native state, and D is the denatured state. On the basis of this model, the parameters of the Arrhenius equation were calculated.
Some reflections on double fertilization, from its discovery to the present
Authors: Raghavan V.
Published: August 2003

The fusion of one sperm with the egg cell to form the embryo and of the other sperm with the polar fusion nucleus to give rise to the endosperm (‘double fertilization’) was discovered by Nawaschin in 1898 in the liliaceous plants, Lilium martagon and Fritillaria tenella. The occurrence of two fusion events analogous to double fertilization has recently been described in some gymnosperm species although the product of the second fusion is a transient embryo, rather than the endosperm as in angiosperms. Recent investigations in angiosperms describe the cell biology and nuclear cytology of double fertilization and the successful in vitro demonstration of the two fusion events using isolated egg cells, central cells, and sperm cells and the development of the fusion products into the embryo and endosperm. Molecular and genetic studies on the component elements of double fertilization have focused on the identification of mutants of Arabidopsis thaliana that display developmental patterns in the seed that result in autonomous endosperm development and even partial embryogenesis in the absence of fertilization. Characterization of the genes and their protein products has provided evidence for a predominant effect of maternal gametophytic genes and of silencing of paternal genes during double fertilization.

Contents

Summary
565

I.
Introduction
566

II.
Discovery of double fertilization
566

III.
Seed development without double fertilization
568

IV.
A case for double fertilization in gymnosperms
570

V.
Structural and cytological perspectives on double fertilization
571

VI.
In vitro double fertilization
575

VII.
Genetic and molecular perspectives
576

VIII.
Concluding comments
578

Acknowledgements
579

References
579
A typology of Korean discount shoppers: shopping motives, store attributes, and outcomes
Authors: Jin Byoungho , Kim Jai‐Ok
Published: August 2003

The internationalization of retailing is increasing throughout the global service markets. Among many retail formats, the discount store is one of the fastest growing formats actively engaging internationalization. In managing retail firms in other cultures, understanding of local customers’ perceptions toward the retail formats is especially important. Shopping motives may be a function of retail format, cultural, economic and social environment. Prior studies on shopping motives, however, have focused on Western cultures and on a shopping mall format. This study provides an exploratory examination of Korean discount shoppers’ shopping motives and their shopping typologies based on their shopping motives. A total of 624 questionnaires were administered to married female discount shoppers in Korea using the intercept survey method, and 467 completed questionnaires were available for data analysis. Factor analysis identified three shopping motives for patronizing discount stores: socialization, diversion and utilitarian. Four groups were identified using cluster analysis and labeled as leisurely‐motivated shoppers (n =152, 34.1 percent), socially‐motivated shoppers (n=49, 11.0 percent), utilitarian shoppers (n=132, 29.6 percent) and shopping‐apathetic shoppers (n=113, 25.3 percent). The four groups significantly differ in their appraisals of patronized store in some of store attributes, repatronage intention, and money spent in a shopping trip. Typologies of each cluster, discount retailing environments and managerial implications are discussed based on findings.
eBusiness and the City of London office market
Authors: Dixon Tim , Marston Andrew , Thompson Bob , Elder Ben
Published: August 2003

This paper is based on major survey of City of London occupiers conducted in the spring and summer of 2002 by The College of Estate Management, Reading. The aim of the research was to examine how eBusiness was driving process change amongst City office occupiers, and how this might change locational and space requirements in the future. This research shows how important information and communications technology (ICT) is becoming in driving process change for City office occupiers. However, ICT must be considered alongside forces for dispersal (for example, transport problems) and agglomeration (for example, face‐to‐face contact), which are creating a potent mix of factors driving businesses in the City. Changes in office densities, created by ICT and other drivers, have important implications for future office space projections in the City. The research shows that caution should be attached to the current office projections in the City provided in the Lord Mayor’s London Plan, and the results also have implications for continued investment in City offices. It is dangerous to over‐simplify density changes caused by ICT and other factors.
Bridging Environmental Science with Environmental Policy: Plasticity of Population, Affluence, and Technology
Authors: York Richard , Rosa Eugene A. , Dietz Thomas
Published: August 2003

Objective. Sound environmental policy is fully dependent upon sound science. However, we have little scientific knowledge of the driving forces behind environmental change. We use the well‐known I = PAT formulation (environmental impacts are the multiplicative product of population, affluence, and technology) as a framework to assess the relative impacts of driving forces. Methods. We introduce the concept ofplasticity—the potential for each factor to vary, particularly because of purposive human action (e.g., policy)—to fine tune our understanding of how each factor can influence different impacts. We illustrate plasticity by assessing each driving force for a variety of environmental impacts. Results. We demonstrate that population, affluence, and technology have different potentials for mitigating different types of impacts and that no one factor is of greater importance than the others. Conclusions. We conclude that plasticity measures can guide policymakers toward identifying and prioritizing those environmental problems most responsive to policy solution.
Who's Minding the Kids? Pollucion, Public Schools, and Environmental Justice in Los Angeles
Authors: Pastor, Jr. Manuel , Sadd James L. , Morello‐Frosch Rachel
Published: August 2003

Objective. Although previous environmental justice research has focused on analysis of the disproportionate burden of environmental hazards on minority residents, few studies have examined demographic inequities in health risks among children. This article evaluates the demographic distribution of potentially hazardous facilities and health risks associated with ambient air toxics exposures among public schoolchildren in the Los Angeles Unified School District. Methods. We combine Geographic Information System analysis with multivariate statistics to compare enrollment and demographic information for students who attend district schools with the spatial pattern of land use, locations of toxic emissions and facilities, and calculated indices of estimated lifetime cancer risk and respiratory hazards associated with exposures to toxic air emissions. Results. District schools are more likely to be located in census tracts containing potentially hazardous facilities; however, these tracts actually have slightly lower cancer and respiratory health risks associated with air toxics when compared to other tracts in the district. Demographic comparisons among school sites indicate that minority students, especially Latinos, are more likely to attend schools near hazardous facilities and face higher health risks associated with outdoor air toxics exposure. Conclusions. These patterns of hazard exposure and health risk should be considered both in the process of siting new schools to house the rapidly growing regional student population and in remediation efforts at existing schools.
Do We Trust the Data? On the Validity and Reliability of Cross‐National Environmental Surveys
Authors: Neumayer Eric
Published: August 2003

Objective. This article provides evidence on the validity and reliability of cross‐national environmental surveys, an aspect that has not found much attention so far. Methods. Validity can be checked in examining whether cross‐national differences in environmental attitudes are in accordance with theoretical hypotheses. For example, a study can claim some validity if concern about inadequate sanitation is strongly negatively correlated with the actual extent of access to sanitation in a country. Results. Several validity checks were undertaken for the Gallup, Gallup, and Dunlap (1993) survey, all of which tend to support its validity. Next, the reliability of cross‐national environmental surveys was checked. Both Pearson and Spearman rank correlations were run for similar questions from differing studies. Most correlations were low and statistically insignificant, however, thus putting some doubt on the reliability of cross‐national environmental surveys, at least with respect to the questions examined. Conclusions. The findings support the validity of cross‐national environmental surveys, but not their reliability. Future surveys should be designed such that validity and reliability checks become easier to undertake.
Framing Effects on Personal Opinion and Perception of Public Opinion: The Cases of Physician–Assisted Suicide and Social Security
Authors: Joslyn Mark R. , Haider–Markel Donald P.
Published: August 2003

Objective. A growing body of literature on issue framing has demonstrated the conditional influence of issue frames on self–reported opinion. The effects of frames are conditioned by message content, the medium of communication, and the predispositions of respondents. However, the literature has yet to explore the influence of issue frames on respondents’ perceptions of public opinion. We draw from the psychological literatures on cognitive accessibility biases and impersonal impact and construct competing hypotheses concerning the likelihood of issue frames affecting perceptions of opinion. Methods. We test hypotheses using data from an experimental field study that exposed respondents to opposing issue frames on two important issues—reforming Social Security and physician–assisted suicide.Results. Our results largely support the impersonal impact hypothesis. Conclusions. We find that available information from issue frames influences personal–level opinion but in general does not affect perceptions of public opinion. We discuss the implications of these findings and suggest avenues for future research.
Contact Theory Extended: The Effects of Prior Racial Contact on Current Social Ties
Authors: Emerson Michael O. , Kimbro Rachel Tolbert , Yancey George
Published: August 2003

Objective. We address methodological limitations in tests of contact theory. Just as importantly, we extend its theoretical focus to behaviors. Linking insights from social and cognitive psychology with contact theory, we hypothesize that prior racial contact will have significant effects on the racial diversity of contemporary social ties. Methods. Using the 1999–2000 Lilly Survey of Attitudes and Social Networks, we conduct univariate and multivariate analyses to test our hypotheses. Results. Those who had experienced prior interracial contact in schools and neighborhoods were more likely, as adults, to have more racially diverse general social groups and friendship circles. They were more likely to attend multiracial as opposed to a uniracial religious congregations, and to be interracially married. In general, these findings applied not only to all Americans, but to whites, African Americans, and Hispanics separately. They did not apply to Asians. Conclusions. Contact theory can and should be extended, rendering it more fruitful for studying race relations. Except when groups are an extremely small percentage of the population, even limited prior contact in multiracial settings appears to have important effects on contemporary social ties. These findings have important policy implications.
Antimicrobial Susceptibilities of
Salmonella
Strains Isolated from Humans, Cattle, Pigs, and Chickens in The Netherlands from 1984 to 2001
Authors: van Duijkeren E. , Wannet W. J. B. , Houwers D. J. , van Pelt W.
Published: August 2003

We monitored antimicrobial susceptibility data for
Salmonella
strains isolated from humans, cattle, pigs, and chickens in The Netherlands from 1984 to 2001 in order to provide insight into the dynamics of resistance over time. The strains were tested for their susceptibilities to seven antimicrobial agents by the agar diffusion method. Resistance was most common in
Salmonella enterica
subsp
. enterica
serovar Typhimurium. Among the strains from humans, pigs, and chickens, it was found that the level of resistance of serovar Typhimurium strains to tetracycline, ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole increased from 1984 to 2001. This increase could be attributed to the emergence of multidrug-resistant serovar Typhimurium DT 104. Among the strains from cattle, it was found that the level of resistance of serovar Typhimurium strains, which was already very high in the 1980s, declined during the study period to the same levels as those for the strains from the other species from 1996 to 2001. Serovar Enteritidis isolates remained susceptible during the entire survey period. Among serovar Paratyphi B variation Java strains isolated from chickens, resistance to furazolidone, flumequine, trimethoprim-sulfamethoxazole, and ampicillin emerged, although furazolidone was not used after 1990. Together, the data indicate that the levels and patterns of resistance differed considerably between
Salmonella
serovars isolated from one host species.
Detection of
Chlamydia trachomatis
and
Neisseria gonorrhoeae
by Strand Displacement Amplification and Relevance of the Amplification Control for Use with Vaginal Swab Specimens
Authors: Cosentino Lisa A. , Landers Daniel V. , Hillier Sharon L.
Published: August 2003

Vaginal swab specimens may be preferable to cervical swab or urine specimens for the detection of
Chlamydia trachomatis
and
Neisseria gonorrhoeae
because of the ease of specimen collection and transport. The purpose of this study was to evaluate whether vaginal swab specimens are equivalent to cervical swab specimens for the detection of
N. gonorrhoeae
and
C. trachomatis
by the Becton Dickinson strand displacement amplification assay (SDA) with the BDProbeTec ET instrument and then to evaluate the use of the amplification control in a clinical research setting. In the first phase, vaginal and cervical swab specimens were obtained from 455 symptomatic women aged 18 to 40 attending primary health care and sexually transmitted disease clinics. Thirty-nine specimens (8.6%) had true-positive results for
N. gonorrhoeae
and 37 specimens (8.1%) had true-positive results for
C. trachomatis
. The sensitivity of SDA was superior to that of culture for the detection of
N. gonorrhoeae
with vaginal swab specimens and equivalent to that of the Roche PCR for the detection of
C. trachomatis
with cervical swab specimens. In the second phase of the study, 1,411 consecutively collected vaginal swab specimens were evaluated, with 357 (25.3%) specimens giving indeterminate readings on the basis of the result for the amplification control. The prevalences of sexually transmitted pathogens in vaginal swab specimens with and without use of the amplification control were 6.0 and 5.8%, respectively, for
C. trachomatis
and 3.1 and 3.0%, respectively, for
N. gonorrhoeae.
Although, vaginal swab specimens were equivalent to cervical swab specimens for the detection of
N. gonorrhoeae
and
C. trachomatis
by SDA with respect to sensitivity, one in four vaginal swab specimens yielded an indeterminate result when the amplification control was used. The amplification control has limited value for use with vaginal swab specimens.
Activities of Caspofungin, Itraconazole, Posaconazole, Ravuconazole, Voriconazole, and Amphotericin B against 448 Recent Clinical Isolates of Filamentous Fungi
Authors: Diekema D. J. , Messer S. A. , Hollis R. J. , Jones R. N. , Pfaller M. A.
Published: August 2003

We examined the in vitro activity of caspofungin, posaconazole, voriconazole, ravuconazole, itraconazole, and amphotericin B against 448 recent clinical mold isolates. The endpoint for reading caspofungin was the minimum effective concentration (MEC). Among the triazoles, posaconazole was most active, inhibiting 95% of isolates at ≤1 μg/ml, followed by ravuconazole (91%), voriconazole (90%), and itraconazole (79%). Caspofungin and amphotericin B inhibited 93% and 89% of isolates at ≤1 μg/ml, respectively, with caspofungin demonstrating an MEC 90 of 0.12 μg/ml. All three new triazoles and caspofungin inhibited >95% of
Aspergillus
spp. at ≤1 μg/ml compared to 83% for itraconazole and 91% for amphotericin B. Amphotericin B inhibited only 38% of
Aspergillus terreus
isolates at ≤1 μg/ml, whereas the three new triazoles and caspofungin inhibited all
A. terreus
at ≤0.5 μg/ml. The new triazoles and caspofungin have excellent in vitro activity against a very large collection of recent clinical isolates of
Aspergillus
spp., and some in vitro activity against selected other filamentous fungi.
Serodiagnosis of Syphilis: Antibodies to Recombinant Tp0453, Tp92, and Gpd Proteins Are Sensitive and Specific Indicators of Infection byTreponema pallidum
Authors: Van Voorhis Wesley C. , Barrett Lynn K. , Lukehart Sheila A. , Schmidt Bruno , Schriefer Martin , Cameron Caroline E.
Published: August 2003

Syphilis serodiagnosis relies on a combination of nonspecific screening tests (antilipoidal antibodies) andTreponema pallidum-specific tests (anti-T.pallidumantibodies). We studied a group of six recombinantT.pallidumantigens for their sensitivities and specificities with sera from individuals with syphilis (n= 43), relapsing fever (n= 8), Lyme disease (n= 8), and leptospirosis (n= 9) and from uninfected individuals (n= 15). Three recombinant proteins, Tp0155, Tp0483, and Tp0751, demonstrated sensitivity values that ranged from 28 to 42%. In contrast, three other recombinant proteins exhibited the following sensitivity and specificity values: Tp0453, 100% sensitivity and 100% specificity; Tp92 (Tp0326), 98% sensitivity and 97% specificity; and Gpd (Tp0257), 91% sensitivity and 93% specificity. Tp0453, Tp92, and Gpd also were recognized by sera from individuals with early primary syphilis that were nonreactive with the antilipoidal Venereal Disease Research Laboratory test. The reactivities of syphilis patient sera with Tp0453, Tp92, and Gpd were proportional to the titers of these sera with the treponemal test MHA-TP (microhemagglutination assay forT.pallidum). Thus, the recombinantT.pallidumantigens Tp0453, Tp92, and Gpd show promise as diagnostic antigens in the enzyme-linked immunosorbent assay-based assay.
Secreted Portion of Glycoprotein G of Herpes Simplex Virus Type 2 Is a Novel Antigen for Type-Discriminating Serology
Authors: Görander Staffan , Svennerholm Bo , Liljeqvist Jan-Åke
Published: August 2003

The secreted portion of glycoprotein G (sgG-2) of herpes simplex virus type 2 (HSV-2) was evaluated as a novel antigen in an enzyme-linked immunosorbent assay (ELISA) format for detection of type-specific immunoglobulin G (IgG) antibodies in HSV-2-infected patients. The results were compared with those obtained by a commercially available assay, the HerpeSelect 2 ELISA (the FOCUS2 assay). Five different panels of sera were analyzed: panel A consisted of 109 serum samples from patients with a culture-proven HSV-1 infection that were Western blotting (WB) negative for HSV-2; panel B consisted of 106 serum samples from patients with a culture-proven recurrent HSV-2 infection that were WB positive for HSV-2; panel C consisted of 100 serum samples with no detectable IgG antibodies against HSV-1 and HSV-2; panel D consisted of 70 HSV-2 negative “tricky” serum samples containing antinuclear IgG antibodies or IgM antibodies against other viruses or bacteria; and panel E consisted of consecutive serum samples from 21 patients presenting with a first episode of HSV-2-induced lesions. When sera in panels A to C were analyzed, the sgG-2 ELISA and the FOCUS2 assay both showed sensitivities and specificities of ≥98%. In total, among the samples in panel D, 13 serum samples (19%) were false positive by the FOCUS2 assay and 1 serum sample (1.4%) was false positive by the sgG-2 ELISA. When the sera in panel E were analyzed, the sgG-2 ELISA detected seroconversion somewhat later than WB or the FOCUS2 assay did. We conclude that sgG-2 induces an HSV-2 type-specific antibody response and can be used for type-discriminating serology.
PCR-Reverse Line Blot Typing Method Underscores the Genomic Heterogeneity of
Borrelia valaisiana
Species and Suggests Its Potential Involvement in Lyme Disease
Authors: Godfroid Edmond , Min Hu Chang , Humair Pierre-François , Bollen Alex , Gern Lise
Published: August 2003

Detection of the
Borrelia burgdorferi
sensu lato complex in biological samples is currently done by conventional immunological and molecular biological methods. To improve on the accuracy of these methods and to simplify the procedure for testing large numbers of samples, a solid-phase sandwich hybridization system readily applicable to the detection of PCR products has been designed. This colorimetric detection system relies on the use of polybiotinylated detection probes and of specific capture oligonucleotides covalently linked at allocated positions on nylon membrane strips. From a phylogenetic analysis on a great number of
ospA
gene sequences, we have designed and synthesized a set of PCR primers specific to the five
Borrelia burgdorferi
sensu lato genospecies present in Europe and a subset of probes (capture and detection probes) specific to these five genospecies (
B. burgdorferi
sensu stricto,
B. garinii
,
B. afzelii
,
B. valaisiana
, and
B. lusitaniae
). This combined PCR hybridization system was evaluated with a large number of various
B. burgdorferi
isolates and clinical specimens. These analyses clearly showed that the system could be used as a typing method to distinguish five genospecies belonging to the
B. burgdorferi
sensu lato complex. In addition, the study showed that
B. valaisiana
strains might be more heterologous than suspected up to now and clustered into three genomic groups.
Rapid and Sensitive Assays for Determination of Hepatitis B Virus (HBV) Genotypes and Detection of HBV Precore and Core Promoter Variants
Authors: Hussain Munira , Chu Chi-Jen , Sablon Erwin , Lok Anna S. F.
Published: August 2003

Hepatitis B virus (HBV) genotypes may influence HBeAg seroconversion rates, mutational patterns in the precore (PC) and core promoter (CP) regions, severity of liver disease, and response to antiviral treatment. Development of rapid, simple, and standardized assays to detect viral genotypes and common mutations in the PC and CP regions can accelerate research on the clinical significance of these variants. We aim to assess the accuracy of a line probe assay in determining HBV genotypes and detecting HBV PC and CP variants. HBV genotypes in 701 patients and PC and CP variants in 600 patients with chronic HBV infection from China and the United States were studied using the INNO-LiPA assay. All but one (99.9%) sample were classified by the genotyping assay. All eight genotypes, i.e., A to H, were found. The INNO-LiPA genotyping assay results were completely concordant with those of sequencing. Using the INNO-LiPA PC assay, 99.8 and 94.7% samples were classifiable in the PC and CP regions, respectively. The PC assay results were completely concordant with those of sequencing in all samples that showed either wild-type or variant sequence. The line probe assay was more sensitive in detecting mixtures than was direct sequencing. By INNO-LiPA, only 50 and 27% of the samples, with mixed wild-type and variant sequence in the PC and CP region, respectively, showed mixed sequence by direct sequencing. INNO-LiPA is rapid, sensitive, and reliable—thus enabling accurate determination of HBV genotypes and detection of PC and CP variants in a large population of patients.
Evidence of Parvovirus Replication in Cerebral Neurons of Cats
Authors: Url Angelika , Truyen Uwe , Rebel-Bauder Barbara , Weissenböck Herbert , Schmidt Peter
Published: August 2003

The correlation between parvovirus infections and lesions in the central nervous system other than cerebellar hypoplasia was studied in 100 cats. The animals were necropsied with a history of various diseases, one third showing typical clinical and pathomorphological signs of panleukopenia. In 18 cats polyclonal antiserum against canine parvovirus consistently labeled neurons mainly in diencephalic regions, whereas the cerebellar cortex remained negative in all cases. In situ hybridization with digoxigenin-labeled minus-sense RNA probes, hybridizing with monomer-replicative form DNA or mRNA, revealed positive signals in nuclei of several neurons of the brain, again excluding the cerebellum. PCR applied to formalin-fixed and paraffin-embedded brain tissue and intestinal tissues of the diseased cats and subsequent DNA sequence analysis yielded canine parvovirus type 2 (CPV-2)-like sequences in the central nervous system. Two aspects of these findings are intriguing: (i) parvoviruses appear to be capable of replicating in neurons, cells that are considered to be terminally differentiated and (ii) CPV-like viruses of the old antigenic type CPV-2 appear to be able to infect cats.
Evaluation of a Rapid PCR Assay for Diagnosis of Meningococcal Meningitis
Authors: Richardson David C. , Louie Lisa , Louie Marie , Simor Andrew E.
Published: August 2003

We compared the results of Gram staining and culture of cerebrospinal fluid to results obtained with a rapid PCR assay for the diagnosis of meningococcal meningitis in 281 cases of suspected bacterial meningitis. PCR had a sensitivity of 97% compared to a sensitivity of 55% for culture, and the PCR specificity was 99.6%. PCR results were available within 2 h of the start of the assay.
Modification of the Double-Disk Test for Detection of
Enterobacteriaceae
Producing Extended-Spectrum and AmpC β-Lactamases
Authors: Pitout J. D. D. , Reisbig M. D. , Venter E. C. , Church D. L. , Hanson N. D.
Published: August 2003

Detection of extended-spectrum β-lactamases (ESBLs) in AmpC-producing
Enterobacteriaceae
is problematic. A modification of the double-disk test (MDDT) has been developed for successful detection of ESBLs in gram-negative bacilli producing well-characterized β-lactamases as well as 212 clinical isolates of
Enterobacter cloacae
,
Enterobacter aerogenes
,
Serratia marcescens
, and
Citrobacter freundii
. MDDT accurately differentiated between ESBL producers and derepressed chromosomal AmpC mutants. MDDT provides a cost-effective alternative approach for clinical microbiology laboratories for routine susceptibility testing with simultaneous detection of ESBLs in
Enterobacteriaceae
.
Strains of
Streptococcus pyogenes
from Severe Invasive Infections Bind HEp2 and HaCaT Cells More Avidly than Strains from Uncomplicated Infections
Authors: Edwards Mandy L , Fagan Peter K. , Smith-Vaughan Heidi , Currie Bart J. , Sriprakash Kadaba S.
Published: August 2003

Epidemiologically unrelated
Streptococcus pyogenes
strains isolated from blood, throat, and skin were assayed for adherence to HEp2 and HaCaT cells. Invasive isolates showed significantly higher avidity for these cell lines than isolates from skin and throat. In general,
S. pyogenes
showed greater binding to HaCaT cells than to HEp2 cells.