bluuebunny/crossref_metadata_2025 huggingface dataset:
Retail Tobacco Outlet Density and Youth Cigarette Smoking: A Propensity-Modeling Approach
Authors: Novak Scott P. , Reardon Sean F. , Raudenbush Stephen W. , Buka Stephen L.
Published: March 2006

Objectives. We examined whether retail tobacco outlet density was related to youth cigarette smoking after control for a diverse range of neighborhood characteristics.

Methods. Data were gathered from 2116 respondents (aged 11 to 23 years) residing in 178 census tracts in Chicago, Ill. Propensity score stratification methods for continuous exposures were used to adjust for potentially confounding neighborhood characteristics, thus strengthening causal inferences.

Results. Retail tobacco outlets were disproportionately located in neighborhoods characterized by social and economic disadvantage. In a model that excluded neighborhood confounders, a marginally significant effect was found. Youths in areas at the highest 75th percentile in retail tobacco outlet density were 13% more likely (odds ratio [OR]=1.13; 95% confidence interval [CI]=0.99, 1.28) to have smoked in the past month compared with those living at the lowest 25th percentile. However, the relation became stronger and significant (OR=0.21; 95% CI=1.04, 1.41) after introduction of tract-level confounders and was statistically significant in the propensity score–adjusted model (OR = 1.20; 95% CI = 1.001, 1.44). Results did not differ significantly between minors and those legally permitted to smoke.

Conclusions. Reductions in retail tobacco outlet density may reduce rates of youth smoking.
Couples’ Immigration Status and Ethnicity as Determinants of Breastfeeding
Authors: Gibson-Davis Christina M. , Brooks-Gunn Jeanne
Published: March 2006

Objectives: We investigated how couples’ immigration status and ethnicity determined the decision to initiate breastfeeding and to breastfeed at 6 months.

Methods: From data collected on 4207 mothers and 3013 fathers participating in a longitudinal birth cohort study, we used linear regression and covariate-adjusted proportions to estimate the determinants of breastfeeding behaviors. The sample was divided by immigration status (either foreign born or born in the United States) and further subdivided by ethnicity (Mexican Hispanic, non-Mexican Hispanic, and non-Hispanic).

Results: Mothers born in the United States had an 85% reduction in the odds of breastfeeding as compared to foreign-born mothers and a 66% reduction in the odds of breastfeeding at 6 months. Each additional year of US residency decreased the odds of breastfeeding by 4%. These differences by immigration status were seen for Mexicans, other Hispanics, and non-Hispanics.

Conclusion: The Hispanic paradox may extend to other non-Hispanic immigrants for breastfeeding behaviors, but may not be true for Hispanic mothers born in the United States. Low rates of breastfeeding for Hispanic American mothers indicate that they should not be overlooked by breastfeeding promotion programs.
Diabetes Decision Support: Initial Experience With the Vermont Diabetes Information System
Authors: MacLean Charles D. , Littenberg Benjamin , Gagnon Michael
Published: March 2006

Interventions that have proven effective in the management of chronic illness have often been difficult to establish in widespread practice. The Chronic Care Model provides a framework for implementing interventions, but it is expensive and difficult to implement.

We developed a decision support system based on this model to improve the care of adults who have diabetes and receive primary care in Vermont or adjacent New York. The Vermont Diabetes Information System uses a network of community laboratories for providing data to produce flowsheets, reminders, action alerts, and population reports that are sent to primary care providers by fax and to patients by mail. Currently, 7295 patients are cared for by 124 primary care providers in 62 practices and are enrolled in a randomized controlled trial to study its effects.
Associations Between Witnessing Parental Domestic Violence and Experiencing Depressive Symptoms in Filipino Adolescents
Authors: Hindin Michelle J. , Gultiano Socorro
Published: March 2006

Objectives. We examined the association between 2 important public health problems in the developing world: parental domestic violence and depressive symptoms during adolescence.

Methods. Data on depressive symptoms and witnessing of domestic violence were obtained during private face-to-face interviews conducted in 2002 with 2051 Filipino adolescents 17–19 years of age.

Results. Symptoms of depression were common; 11% of young men and 19% of young women reported wishing that they were dead occasionally or most of the time, and nearly half of all respondents recalled parental domestic violence. Female adolescents had significantly higher scores than male adolescents on a 12-item index of depressive symptoms. Both male and female adolescents who had witnessed parental domestic violence reported more depressive symptoms.

Conclusions. Filipino adolescents who have witnessed parental domestic violence are significantly more likely to report depressive symptoms.
Racial and Ethnic Disparities in Diagnosed and Possible Undiagnosed Asthma Among Public-School Children in Chicago
Authors: Quinn Kelly , Shalowitz Madeleine U. , Berry Carolyn A. , Mijanovich Tod , Wolf Raoul L.
Published: March 2006

Objectives. We examined racial and ethnic disparities in the total potential burden of asthma in low-income, racially/ethnically heterogeneous Chicago schools.

Methods. We used the Brief Pediatric Asthma Screen Plus (BPAS+) and the Spanish BPAS+, validated, caregiver-completed respiratory questionnaires, to identify asthma and possible asthma among students in 14 racially/ethnically diverse public elementary schools.

Results. Among 11490 children, we demonstrated a high lifetime prevalence (12.2%) as well as racial and ethnic disparities in diagnosed asthma, but no disparities in prevalences of possible undiagnosed asthma. Possible asthma cases boost the total potential burden of asthma to more than 1 in 3 non-Hispanic Black and Puerto Rican children.

Conclusions. There are significant racial and ethnic disparities in diagnosed asthma among inner-city schoolchildren in Chicago. However, possible undiagnosed asthma appears to have similar prevalences across racial/ethnic groups and contributes to a high total potential asthma burden in each group studied. A better understanding of underdiagnosis is needed to address gaps in asthma care and intervention for low-income communities.
Relationships between Factors Affecting Contraception and Fertility in Bangladesh
Authors: Kabir Ahmad , Ibrahim Q. I. U. , Kawsar L. A.
Published: March 2006

Using the data derived from the 1989 Bangladesh Fertility Survey, the 1993–94 and 1996–97 Bangladesh Demographic and Health surveys, this study attempts to find the relationships between the factors affecting contraception and fertility among currently married women by using a linear recursive path model which provides direct and indirect relationships between the variables. The results suggest that women's status had a significant negative effect on childbearing and it had a significant positive effect on the use of contraception. It was also observed that higher incidence of child mortality led to a higher level of fertility.
A Randomized Trial of the Efficacy of Group Therapy in Changing Viral Load and CD4 Counts in Individuals Living with HIV Infection
Authors: Belanoff Joseph K. , Sund Brenda , Koopman Cheryl , Blasey Christine , Flamm Jason , Schatzberg Alan F. , Spiegel David
Published: March 2006

Objective:

This randomized pilot study evaluates whether seropositive patients who are randomly assigned to receive a supportive-expressive group therapy plus education intervention show greater improvements in increased immune function and decreased viral load compared to those randomly assigned to an education-only intervention.

Method:

Fifty-nine individuals who had been HIV-seropositive for at least 6 months prior to inclusion in the study and had been receiving standard pharmacologic treatment were entered in a prospective randomized trial of the effects of weekly supportive-expressive group therapy on changes in immune status. Participants were matched for AIDS status and sex and randomized to receive weekly sessions of group psychotherapy plus educational materials on HIV/AIDS, or to receive the educational materials alone. Participants were assessed before treatment and then 12 weeks later.

Results:

Individuals who were randomized to group therapy showed a statistically significant increase in CD4 count and decrease in HIV viral load. Among individuals randomized to the education only condition, no significant change occurred in CD4 count or viral load.

Conclusions:

These results provide preliminary data suggesting that HIV-seropositive individuals who receive supportive-expressive group psychotherapy may experience concomitant improvements in CD4 cell count and viral load. Further research with a larger sample should examine the possible underlying mechanisms of such benefits.
Multimedia and Hypermedia Solutions for Promoting Metacognitive Engagement, Coherence, and Learning
Authors: McNamara Danielle S. , Shapiro Amy M.
Published: March 2006

Users of educational hypertext are faced with the challenge of creating meaning both within and between texts. Cohesion is an important factor contributing to whether a reader is able to capture meaning and comprehend text. When readers are required to fill in conceptual gaps in text, comprehension can fail if they do not have sufficient knowledge. Cohesion helps low-knowledge readers to create a more coherent mental representation of the text. However, text that is too cohesive can inhibit active processing, and thus reduce coherence for more knowledgeable readers. Similar patterns have been found for hypertext, which requires readers to create coherence between multiple electronic texts. Domain novices are in greater need of explicit pointers to important links between documents and gain from having less control over system navigation. Domain experts are in less need of scaffolding within the system. We discuss the use of a multimedia reading strategy training program to help low-knowledge readers better understand less cohesive text. Finally, we discuss four principles to guide hypertext development geared toward improving coherence and metacognitive engagement.
Road Safety Practices among Commercial Motorcyclists in a Rural Town in Nigeria: Implications for Health Education
Authors: Amoran O. E. , Eme Owoaje , Giwa O. A. , Gbolahan O. B.
Published: March 2006

This cross-sectional, community-based study was carried out among commercial motorcyclists in Igboora. All the commercial motor parks in Igboora were visited and all the commercial motorcyclists who consented to participate in the study were interviewed. Information on the respondents' socio-demographic characteristics, and the practice of road safety measures was collected using an interviewer administered questionnaire. A total of 299 motorcyclists were interviewed. All (100%) of them were males. The mean age of the respondents was 27.4 ± 7.4 years. One hundred eighty-two (60.7%) of the motorcyclists had the correct knowledge of the purpose of Highway Code. Only 70 (23.3%) could recognize more than half of the currently used road safety codes and 47 (15.7%) obey these road safety codes more than half of the time they see it. Only 183 (61.2%) of them had a driving license and 72 (24.1%) were able to produce these licenses on demand. All (100%) of the respondents did not use any protective helmet. Those who have longer years of working experience, higher level of education and higher knowledge of the safety codes practice it more regularly ( r = 0.198, p = 0.001, χ2 = 9.31, p = 0.025, and r = 0.28, p = 0.001 respectively). One hundred thirty-six (45.5%) have been involved in at least one accident in the preceding year. The overall incidence of road traffic accident was 2.16 per 1,000. There was however on statistically significant association between the practice of road safety codes and the occurrence of road traffic accidents (χ2 = 0.176, p = 0.916). The study shows that the practice of road safety measures was low in this rural Nigerian community and was not associated with the incidence of road traffic accidents. Introducing road safety education particularly targeted at educating the motorcyclists on the importance and practice of road safety measures would lead to an increase in the practice of the safety measures and hopefully a reduction in the incidence of road traffic accidents.
Burnout in Psychiatrists: An Etiological Model
Authors: Kumar Shailesh , Hatcher Simon , Huggard Peter
Published: March 2006

Objective:

This article reviews burnout in psychiatrists. A model of burnout is presented which considers three factors: those which may predispose, precipitate, and perpetuate burnout. Lastly, recommendations are made for future research.

Methods:

We conducted a selective literature review to expand on two recent systematic reviews to examine the etiology, prevalence, and consequences of burnout in psychiatrists. We distinguish the effects of burnout, depression, and work-related stress.

Results:

An etiological model for the development of burnout in psychiatrists is described here in terms of an interaction between the predisposing, precipitating, and perpetuating factors.

Conclusions:

Research is needed on the long-term effects of work-place stress on psychiatrists, to identify possible protective factors, and to utilize this information to inform the design of interventions that protect or mitigate the effects of work-place stress on psychiatrists.
Using Computer-Based Technology to Determine Emergent Classroom Discipline Styles in Preservice Teacher Education
Authors: Lee Seungyoun , Powell Jack V.
Published: March 2006

Problems related to disruptive behaviors of children in schools continue to be a topic of public debate and empirical inquiry among teachers and researchers across America. Although this problem is historic, it has resurfaced, with momentous attention during recent years. This article focuses on a computerized simulation used as an integrated component of a curriculum course. The simulation includes discipline issues with certain situations as one of six categories of emphasis. The researchers attempted to ascertain the extent to which the simulation influenced selected disciplines styles of preservice teachers before and after field experience. Chi-square, Somers'd, Gamma, Correlation, and Regression were applied to the data using after field experience as a dependent variable. Significant difference was found on “rating of simulation on discipline before–after field experience” with Chi-square analyses (χ2 = 27.196; df = 12; p < 0.007), and with regression analyses ( b = .249). Thus, preservice teachers who experienced a computerized simulation on discipline before field experience perceived the computerized simulation on discipline as an effective tool to learn discipline after their four-week field experience. Computerized simulation is shown to be helpful to preservice early childhood teachers prior to field experience. Therefore, integrating technology-based simulations into preservice teacher education programs can potentially and effectively influence solving discipline problems in real classrooms by helping preservice teachers construct their own beliefs and philosophy about discipline. Emergent themes and direct quotes from preservice early childhood teachers are shown on the aspect of discipline.
Learning to See Differently: Viewing Technology Diffusion in Teacher Education through the Lens of Organizational Change
Authors: Wang Yu-Mei , Patterson Jerry
Published: March 2006

While the discussion on the topic of technology diffusion in teacher education primarily centers on course design, program development, and faculty technology training, this article explores technology diffusion from the perspective of organizational change. Technology diffusion in teacher education is a multi-faceted task and, therefore, requires multi-dimensional approaches. Systemic technology diffusion involves a paradigm shift in thinking about organizational change. The balance of this article applies this paradigm shift to analyze some seemingly puzzling phenomena that has occurred in the technology diffusion process and, thus, to help leaders of IT change initiatives to increase the chances of successful implementation.
The Ideology of Performative Pedagogies: A Cultural Symptomology
Authors: Hides Shaun
Published: March 2006

This article examines the interplay of power, identity and culture within online learning in higher education. Specifically it addresses the relation between online learning, or e-learning, and the apparent disappearance of ideology within postmodernity, in the context of teaching highly diverse cohorts of students. This conjunction is theorised through Slavoj Žižek's 1990s critique of multiculturalism and ideas of the symptom and interpassivity. The engagement with the ‘cultural difference’ of ‘international students’ problematises one current orthodoxy of online learning, enabling the re-conceptualisation of the ideological confrontation in this context as one between perfomativity-informationalisation and friction, difference and cultural engagement.
Who are You? Weblogs and Academic Identity
Authors: Ewins Rory
Published: March 2006

The weblog format has increasingly been adopted by academics in recent years, both as a teaching tool and to disseminate and discuss their own research interests. Academics are turning to blogs to exchange ideas about their discipline, their wider field, the academy, and beyond. Doing so, however, raises questions about personal identity with implications for life beyond the blog.

Academics, because of the public nature of weblogs, the self-reflection encouraged by the form, and their analytical frame of mind, serve as useful case studies in exploring these questions. This article explores what it means to have an online identity in the light both of works by two commentators on identity in the postmodern world, Madan Sarup and Walter Truett Anderson, and of the author's own experience of blogging over the past five years. Weblogs, while they afford opportunities for identity construction and reconfiguration, can end up changing their authors' sense of identity in ways they may not expect.
Who are You? Theorising from the Experience of Working through an Avatar
Authors: Jones Chris
Published: March 2006

This article explores the experience of a researcher who was part of a pan-European team exploring one of the currently available avatar worlds used for educational purposes. The article reports research undertaken as part of the European Union (EU)-funded project EQUEL (e-quality in e-learning) from the point of view of a single researcher. The EQUEL project was organised into several Significant Interest Groups (SIGs) and the Agora SIG was set up to explore knowledge-sharing in 3D (three-dimensional) avatar-based systems, in particular Active Worlds Educational Universe (AWEDU – http://www.activeworlds.com ). AWEDU is a relatively common, stable and explored 3D system. Further details of the research reported here can be found in papers presented by Jensen and Fejfer Olsen et al at the networked learning conference 2004 ( http://www.networkedlearningconference.org.uk/past/nlc2004 ).
Ceramic membranes for ammonia recovery
Authors: Camus Olivier , Perera Semali , Crittenden Barry , van Delft Yvonne C. , Meyer Dick F. , P. A. C. Pex Paul , Kumakiri Izumi , Miachon Sylvain , Dalmon Jean‐Alain , Tennison Steve , Chanaud Philippe , Groensmit Ernest , Nobel Wil
Published: March 2006

An extensive screening program has been performed to find a suitable membrane configuration and operating conditions for the effective recovery of ammonia from the syngas loop. All the experiments have been performed at steady state. MFI zeolite membranes in tubular and multi‐channel fiber configurations have been tested along with tubular silica membranes. At 80°C, a high ammonia permeance (2.1 × 10−7 mol.m−2.s−1.Pa−1), and a selectivity of about 10 were found with the tubular zeolite membrane, whereas for the silica membrane an even higher ammonia permeance was measured (7.6 x 10−7 mol.m−2.s−1.Pa−1) with a selectivity of about 7. For both silica and zeolite membranes, the selectivity was found to increase with increasing temperature up to 80°C. This is a combined effect of weaker adsorption of ammonia and increased diffusion at higher temperature. The results have been modeled using both the well‐mixed reactor and the log mean pressure difference approaches. To overcome their limitations in addressing changes in feed concentration along the membrane surface, a segmental model has been used to obtain suitable operating conditions and membrane areas required for an industrial application. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Evidence that variation in the peripheral benzodiazepine receptor (PBR) gene influences susceptibility to panic disorder
Authors: Nakamura Kazuhiko , Yamada Kazuo , Iwayama Yoshimi , Toyota Tomoko , Furukawa Aizou , Takimoto Takahiro , Terayama Hayato , Iwahashi Kazuhiko , Takei Nori , Minabe Yoshio , Sekine Yoshimoto , Suzuki Katsuaki , Iwata Yasuhide , Pillai Anitha , Nakamoto Yurie , Ikeda Kazutaka , Yoshii Mitsunobu , Fukunishi Isao , Yoshikawa Takeo , Mori Norio
Published: March 2006

Panic disorder (PD) is the repeated sudden occurrence of panic attacks, episodes characterized by psychological symptoms. Peripheral benzodiazepine receptor (PBR) is closely associated with personality traits for anxiety tolerance, and that it holds promise as a biological marker of stressful conditions. We have performed association analyses using the polymorphism to determine the PBR in PD. We screened the subjects for sequence variations within the 5′ region, the coding region (exons 2–4), and the 3′ noncoding region. One novel missense variant in exon 4, derived from the nucleotide transition in codon 162 (CGT → CAT:485G > A) resulting in an arginine‐to‐histidine (Arg → His) change, was detected in these subjects. The 485G > polymorphism of the PBR gene was analyzed in 91 PD patients and 178 controls. The genotypic and allelic analyses of the 485G > A revealed significant differences between the panic patients and the comparison subjects (P = 0.021 and 0.014, respectively). The present study provides new and important evidence that variation in the PBR gene influences susceptibility to PD. © 2006 Wiley‐Liss, Inc.
The OCD collaborative genetics study: Methods and sample description
Authors: Samuels Jack F. , Riddle Mark A. , Greenberg Benjamin D. , Fyer Abby J. , McCracken James T. , Rauch Scott L. , Murphy Dennis L. , Grados Marco A. , Pinto Anthony , Knowles James A. , Piacentini John , Cannistraro Paul A. , Cullen Bernadette , Bienvenu O. Joseph , Rasmussen Steven A. , Pauls David L. , Willour Virginia L. , Shugart Yin Y. , Liang Kung‐yee , Hoehn‐Saric Rudolf , Nestadt Gerald
Published: March 2006

Results from twin and family studies suggest that obsessive‐compulsive disorder (OCD) may be transmitted in families but, to date, genes for the disorder have not been identified. The OCD Collaborative Genetics Study (OCGS) is a six‐site collaborative genetic linkage study of OCD. Specimens and blinded clinical data will be made available through the National Institute of Mental Health (NIMH) cell repository. In this initial report, we describe the methods of the study and present clinical characteristics of affected individuals for researchers interested in this valuable resource for genetic studies of OCD. The project clinically evaluated and collected blood specimens from 238 families containing 299 OCD‐affected sibling pairs and their parents, and additional affected relative pairs, for a genome‐wide linkage study. Of the 999 individuals interviewed to date, 624 were diagnosed with “definite” OCD. The mean age of subjects was 36 years (range 7‐95). The majority of affected individuals (66%) were female. The mean age at onset of obsessive‐compulsive symptoms was 9.5 years. Specific mood disorders, anxiety disorders, eating disorders, and skin picking were more prevalent in female cases, whereas tics, Tourette disorder, and alcohol dependence were more prevalent in male cases. Compared to “definite” cases of OCD, “probable” cases (n = 82) had, on average, later age at onset of obsessive‐compulsive symptoms, lower severity score, and fewer numbers of different categories of obsessions and compulsions, and they were less likely to have received treatment for their symptoms. © 2006 Wiley‐Liss, Inc.
Processing robustness for a phenylethynyl‐terminated polyimide composite
Authors: Hou T. H.
Published: February 2006

The processability of a phenylethynyl‐terminated imide resin matrix (PETI‐5) composite was investigated. Unidirectional prepregs were made through the coating of an N‐methylpyrrolidone solution of an amide acid oligomer (PETAA‐5/NMP) onto unsized IM7 fibers. Two batches of prepregs were used: one was made by the National Aeronautics and Space Administration in house, and the other was from an industrial source. The composite processing robustness was investigated with respect to the prepreg shelf life, the effect of B‐staging conditions, and the optimal processing window. The prepreg rheology and open hole compression (OHC) strengths were not to affected by prolonged ambient storage (i.e., up to 60 days). Rheological measurements indicated that the PETAA‐5/NMP processability was only slightly affected over a wide range of B‐stage temperatures (from 250 to 300°C). The OHC strength values were statistically indistinguishable among laminates consolidated under various B‐staging conditions. An optimal processing window was established with response surface methodology. The IM7/PETAA‐5/NMP prepreg was more sensitive to the consolidation temperature than to the pressure. A good consolidation was achievable at 371°C (700°F)/100 psi, which yielded a room‐temperature OHC strength of 62 ksi. However, the processability declined dramatically at temperatures below 350°C (662°F), as evidenced by the OHC strength values. The processability of the IM7/PETI‐5 prepreg was robust. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3212–3221, 2006
Investigation of liquid diffusion into contact lenses using an electron spin resonance technique
Authors: Özgür Evrim E. , Aydin Emine , Özbey Turan , İrkeç Murat , Bozkurt Banu , Kaptan H. Yılmaz
Published: February 2006

In this study, electron spin resonance (ESR) spectroscopy was used for the first time to investigate liquid diffusion into contact lenses. As contact lenses are not paramagnetic substances, they were labeled with nitroxide spin probes to get an ESR spectrum. Thus, it gives a solid spin‐labeled ESR spectrum. The shape and intensity of the ESR signals depend on the environment of these spin probes. The spin probe environment began to change from solid to liquid if liquid were dropped into the system. Consequently the ESR spectra began to change with time, too. By following these changes, three distinct steps were found. Their diffusion coefficients were determined to be 6.38 × 10−8 cm2/s for the first step (rapid decay region) and 0.37 × 10−8 cm2/s for the second step (slow decay region), and 2.50 × 10−8 cm2/s for the third and last step (desorption region). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2942–2946, 2006
Synthesis and solution properties of novel nonionic functional polyurethane surfactants
Authors: Dong Y. , Jin Y. , Wei D. Q.
Published: February 2006

A series of novel nonionic functional polyurethane surfactants were synthesized by the polycondensation of 2,4‐toluene diisocyanate with poly(propylene oxide) (weight‐average molecular weight = 400, 1000, or 2000) and monoallyl‐end‐capped poly(ethylene oxide). The chemical structure of the polyurethane surfactants was determined by Fourier transform infrared and 1H‐NMR, and the effects of the concentration, salt, rest time, and temperature on the surface tension were investigated. These polymeric surfactants exhibited excellent surface activity. Sample III, which was synthesized with monoallyl‐end‐capped poly(ethylene oxide) (number‐average molecular weight = 1000), poly(propylene oxide) (number‐average molecular weight = 2000), and tolylene diisocyanate, could reduce the surface tension to 37.6 mN/m at a concentration of 0.06 mol/L at 25°C. All polyurethane surfactants synthesized in this study had low critical micelle concentrations (ca. 10−4 to 10−5 mol/L) and could reduce the surface tension even at very low concentration levels. Moreover, the surface tension decreased with an increase in the temperature or the concentration of the polyurethane surfactants. The addition of salt resulted in a decrease in the surface tension, and it took some time for the polyurethane surfactants to reach a constant surface tension value. UV spectra were found to be very useful for determining the critical micelle concentration. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2956–2962, 2006
Oxygen barrier materials from renewable sources: Material properties of softwood hemicellulose‐based films
Authors: Hartman Jonas , Albertsson Ann‐Christine , Lindblad Margaretha Söderqvist , Sjöberg John
Published: February 2006

The aim of this study was to investigate the film‐forming ability of the hemicellulose O‐acetyl‐galactoglucomannan (AcGGM) and to evaluate its potential as a barrier material. The polymer film was evaluated by measurement of its oxygen permeability (Ox‐Tran® Mocon), thermal properties (differential scanning calorimetry), and dynamic mechanical properties under a humidity scan (humidity‐scan DMA). The AcGGM was isolated from industrial process water obtained from mechanical wood pulping. The self‐supporting films were formed by solution‐casting from water. As expected, a plasticizer was needed to avoid brittleness, and glycerol, sorbitol, and xylitol were compared. However, these additives resulted in higher sensitivity to moisture, which might be less beneficial for some applications. Interesting oxygen barrier and mechanical strength properties were achieved in a film obtained from a physical blend of AcGGM and either alginate or carboxymethylcellulose, both having a substantially higher molecular weight than AcGGM. No phase separation was observed, since all the components used were rich in hydroxyl functionalities. When a plasticizer was also added to the binary mixture, a compromise between (1) low O2 permeability, (2) high mechanical toughness, and (3) flexibility of an AcGGM‐based film was obtained. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2985–2991, 2006
Nano‐scaled ordering of hyperbranched and star‐hyperbranched polymers
Authors: Ishizu Koji , Ochi Koichiro , Furukawa Taiichi
Published: February 2006

Hyperbranched polystyrenes (HPS) were prepared by living radical polymerization of 4‐vinylbenzyl N,N‐diethyldithiocarbamate (VBDC) as an inimer under UV irradiation. These HPS exhibited large amounts of photofunctional diethyldithiocarbamate (DC) groups on their outside surfaces. We derived star‐HPS (SHPS) by grafting from such HPS macroinitiator with methyl methacrylate (MMA) or ethyl methacrylate (EMA). The ratios of radius of gyration to hydrodynamic radius Rg/Rh for HPS and SHPS in tetrahydrofuran (THF) were in the range of 0.74–0.90 and 1.05–1.12, respectively. HPS and SHPS behaved in a good solvent as hard and soft spheres, respectively. We demonstrated the structural ordering of both branched polymers in THF through small‐angle X‐ray scattering (SAXS), by varying the polymer concentration. As a result, HPS and SHPS formed face‐centered‐cubic (fcc) and body‐centered‐cubic (bcc) structures, respectively, near the overlap threshold (C*). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3340–3345, 2006
Mechanical and structural characterization of POSS‐modified polyamide 6
Authors: Baldi F. , Bignotti F. , Ricco L. , Monticelli O. , Riccò T.
Published: February 2006

This work investigated the mechanical behavior of POSS‐modified polyamide 6 (PA6), containing PA6 chains terminated at one end with aminopropyl‐heptaisobutyl POSS. Three systems with different POSS contents (5.4, 10.8, and 16.2 wt %), each characterized by a specific molecular mass, and the corresponding PA6 neat polymers were examined. The materials were first subjected to morphological and calorimetric analysis by wide‐angle X‐ray diffraction and differential scanning calorimetry, respectively. Tensile tests, performed on the samples in wet conditions, showed that stiffness, strength, and ductility were appreciably modified by the presence of POSS in the polymeric chains. The relationships among these effects and the microstructural characteristics of the systems also were analyzed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3409–3414, 2006
Long‐Chain 3‐Acyl‐4‐hydroxycoumarins: Structure and Antibacterial Activity
Authors: Cravotto Giancarlo , Tagliapietra Silvia , Cappello Rossella , Palmisano Giovanni , Curini Massimo , Boccalini Marco
Published: March 2006

By reacting 4‐hydroxycoumarin with long‐chain acyl chlorides, a number of new 3‐acyl derivatives were prepared and the relationship was studied between their structures and activities against Staphylococcus aureus ATCC 6538, Staphylococcus epidermidis ATCC 12228, and Propionibacterium acnes ATCC 11827. Antibacterial activity was associated with enolic tautomers of a tricarbonylmethane group bearing a lipophilic side chain (undec‐10‐enoyl, undec‐10‐ynoyl, palmitoyl or octadec‐9‐enoyl). A newly synthesized 2‐acyl derivative of 2H‐indene‐1,3‐dione containing the same tricarbonylmethane motif showed a comparable activity.
Analysis of pigmented villonodular synovitis with genome‐wide complementary DNA microarray and tissue array technology reveals insight into potential novel therapeutic approaches
Authors: Finis Katharina , Sültmann Holger , Ruschhaupt Markus , Buness Andreas , Helmchen Birgit , Kuner Ruprecht , Gross Marie‐Luise , Fink Bernd , Schirmacher Peter , Poustka Annemarie , Berger Irina
Published: March 2006

Objective

To characterize the gene expression profile and determine potential diagnostic markers and therapeutic targets in pigmented villonodular synovitis (PVNS).

Methods

Gene expression patterns in 11 patients with PVNS, 18 patients with rheumatoid arthritis (RA), and 19 patients with osteoarthritis (OA) were investigated using genome‐wide complementary DNA microarrays. Validation of differentially expressed genes was performed by real‐time quantitative polymerase chain reaction and immunohistochemical analysis on tissue arrays (80 patients with PVNS, 51 patients with RA, and 20 patients with OA).

Results

The gene expression profile in PVNS was clearly distinct from those in RA and OA. One hundred forty‐one up‐regulated genes and 47 down‐regulated genes were found in PVNS compared with RA, and 153 up‐regulated genes and 89 down‐regulated genes were found in PVNS compared with OA (fold change ≥1.5;Q≤ 0.001). Genes differentially expressed in PVNS were involved in apoptosis regulation, matrix degradation, and inflammation (ALOX5AP,ATP6V1B2,CD53,CHI3L1,CTSL,CXCR4,HSPA8,HSPCA,LAPTM5,MMP9,MOAP1, andSPP1).

Conclusion

The gene expression signature in PVNS is similar to that of activated macrophages and is consistent with the local destructive course of the disease. The gene and protein expression patterns suggest that the ongoing proliferation in PVNS is sustained by apoptosis resistance. This result suggests the possibility of a potential novel therapeutic intervention against PVNS.
Association of the IL1 gene cluster with susceptibility to ankylosing spondylitis: An analysis of three Canadian populations
Authors: Maksymowych Walter P. , Rahman Proton , Reeve Jeff P. , Gladman Dafna D. , Peddle Lynette , Inman Robert D.
Published: March 2006

Objective

To examine the association between the IL1 gene cluster and susceptibility to ankylosing spondylitis (AS) in 3 independent case–control cohorts.

Methods

We analyzed 394 patients and 446 controls from Alberta, Newfoundland, and Toronto, Canada. Samples were genotyped using a panel of 38 single‐nucleotide polymorphism (SNP) markers within the IL1 gene cluster. Data from 20 informative and nonredundant SNP markers were analyzed using several association test strategies. First, we used the program WHAP to identify single‐marker associations. Second, we used WHAP to analyze “sliding windows” of 3 contiguous markers along the entire extent of the IL1 gene cluster in order to identify haplotypic associations. Third, we used the linkage disequilibrium mapping program DMLE to estimate the posterior probability distribution of a disease locus.

Results

A total of 14 SNP markers showed significant single‐locus disease associations, the most significant being rs3783526 (IL1A) (P = 0.0009 in the Alberta cohort, P = 0.04 in the Newfoundland cohort) and rs1143627 (IL1B) (P = 0.0005 in the Alberta cohort, P = 0.02 in the Newfoundland cohort). Analysis of 3‐marker sliding windows revealed significant and consistent associations with all of the haplotypes in the IL1A and IL1B loci in the Alberta cohort and with IL1B in the Newfoundland cohort, especially haplotypes rs1143634/rs1143630/rs3917356 and rs1143630/rs3917356/rs3917354 (P = 0.006–0.0001). With DMLE, a strong peak in the probability distribution was estimated near IL1A in both the Alberta and the Newfoundland populations.

Conclusion

These results indicate that the IL1 locus, or a locus close to IL1, is associated with susceptibility to AS.
Prevalence of periconceptional folic acid use and perceived barriers to the postgestation continuance of supplemental folic acid: Survey results from a Teratogen Information Service
Authors: Goldberg Beck B. , Alvarado Sonia , Chavez Carmen , Chen Brian H. , Dick Lyn M. , Felix Robert J. , Kao Kelly K. , Chambers Christina D.
Published: March 2006

BACKGROUND

Fewer than 40% of U.S. women are taking folic acid supplements periconceptionally at a time when the risk of neural tube defects (NTDs) can be reduced by supplementation. A better understanding of the vitamin‐taking habits of childbearing‐age women and effective methods for improving periconceptional supplement use are needed.

METHODS

A telephone survey conducted through the California Teratogen Information Service (TIS) between August 2003 and January 2004 assessed the prevalence and characteristics of pregnant callers who did not use folic acid supplements in the periconceptional period, and explored attitudes toward advice to continue vitamin use following pregnancy in order to be protected in a future pregnancy.

RESULTS

A total of 327 pregnant women who called the TIS for information agreed to participate in the survey. More than half (53.2%) were not taking folic acid–containing supplements in the periconceptional period. Predictors of lack of use included a higher prepregnancy body mass index, younger maternal age, non‐white race/ethnicity, lower education level, and unplanned pregnancy. One‐quarter of the women said they would be willing to continue taking vitamins after the pregnancy if advised to do so by a physician. The remainder identified obstacles to following that advice—notably, not planning to become pregnant again and the belief that enough folate is derived from diet alone.

CONCLUSIONS

More than half of the callers to the TIS were not compliant with recommendations regarding periconceptional folic acid supplementation. This represents an opportunity for TIS specialists and physicians to intervene in a current pregnancy to encourage maintenance of supplement use in the subsequent interpregnancy interval. Birth Defects Research (Part A), 2006. © 2006 Wiley‐Liss, Inc.
Pre‐sowing magnetic treatments of tomato seeds increase the growth and yield of plants
Authors: De Souza A. , Garcí D. , Sueiro L. , Gilart F. , Porras E. , Licea L.
Published: March 2006

The effects of pre‐sowing magnetic treatments on growth and yield of tomato (cv Campbell‐28) were investigated under field conditions. Tomato seeds were exposed to full‐wave rectified sinusoidal non‐uniform magnetic fields (MFs) induced by an electromagnet at 100 mT (rms) for 10 min and at 170 mT (rms) for 3 min. Non‐treated seeds were considered as controls. Plants were grown in experimental plots (30.2 m2) and were cultivated according to standard agricultural practices. During the vegetative and generative growth stages, samples were collected at regular intervals for growth rate analyses, and the resistance of plants to geminivirus and early blight was evaluated. At physiological maturity, the plants were harvested from each plot and the yield and yield parameters were determined. In the vegetative stage, the treatments led to a significant increase in leaf area, leaf dry weight, and specific leaf area (SLA) per plant. Also, the leaf, stem, and root relative growth rates of plants derived from magnetically treated seeds were greater than those shown by the control plants. In the generative stage, leaf area per plant and relative growth rates of fruits from plants from magnetically exposed seeds were greater than those of the control plant fruits. At fruit maturity stage, all magnetic treatments increased significantly (P < .05) the mean fruit weight, the fruit yield per plant, the fruit yield per area, and the equatorial diameter of fruits in comparison with the controls. At the end of the experiment, total dry matter was significantly higher for plants from magnetically treated seeds than that of the controls. A significant delay in the appearance of first symptoms of geminivirus and early blight and a reduced infection rate of early blight were observed in the plants from exposed seeds to MFs. Pre‐sowing magnetic treatments would enhance the growth and yield of tomato crop. Bioelectromagnetics 27:247–257, 2006. © 2006 Wiley‐Liss, Inc.
Noise magnetic fields abolish the gap junction intercellular communication suppression induced by 50 hz magnetic fields
Authors: Zeng Qunli , Ke Xueqin , Gao Xiangwei , Fu Yiti , Lu Deqiang , Chiang Huai , Xu Zhengping
Published: March 2006

Previously, we have reported that exposure to 50 Hz coherent sinusoidal magnetic fields (MF) for 24 h inhibits gap junction intercellular communication (GJIC) in mammalian cells at an intensity of 0.4 mT and enhances the inhibition effect of 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) at 0.2 mT. In the present study, we further explored the effects of incoherent noise MF on MF‐induced GJIC inhibition. GJIC was determined by fluorescence recovery after photobleaching (FRAP) with a laser‐scanning confocal microscope. The rate of fluorescence recovery (R) at 10 min after photobleaching was adopted as the functional index of GJIC. The R‐value of NIH3T3 cells exposed to 50 Hz sinusoidal MF at 0.4 mT for 24 h was 30.85 ± 14.70%, while the cells in sham exposure group had an R‐value of 46.36 ± 20.68%, demonstrating that the GJIC of NIH3T3 cells was significantly inhibited by MF exposure (P < .05). However, there were no significant differences in the R‐values of the sham exposure, MF‐plus‐noise MF exposure (R: 49.58 ± 19.38%), and noise MF exposure groups (R: 46.74 ± 21.14%) (P > .05), indicating that the superposition of a noise MF alleviated the suppression of GJIC induced by the 50 Hz MF. In addition, although MF at an intensity of 0.2 mT synergistically enhanced TPA‐induced GJIC inhibition (R: 24.90 ± 13.50% vs. 35.82 ± 17.18%, P < .05), further imposition of a noise MF abolished the synergistic effect of coherent MF (R: 32.51 ± 18.37%). Overall, the present data clearly showed that although noise MF itself had no effect on GJIC of NIH3T3 cells, its superposition onto a coherent sinusoidal MF at the same intensity abolished MF‐induced GJIC suppression. This is the first report showing that noise MF neutralizes 50 Hz MF‐induced biological effect by using a signaling component as the test endpoint. Bioelectromagnetics 27:274–279, 2006. © 2006 Wiley‐Liss, Inc.
Low frequency electromagnetic fields and the Belousov–Zhabotinsky reaction
Authors: Sontag W.
Published: March 2006

Low frequency magnetic fields can influence biochemical reactions and consequently physiological rhythms and oscillations. To test this for a model reaction we used the chemical Belousov–Zhabotinsky (BZ) reaction, which is one of the simplest chemical oscillators. The oscillation frequency of the reaction was tracked optically by the absorption of blue light. Field treatment was carried out at room temperature in the middle of two Helmholtz coils. After starting the reaction, for 5 min the oscillations were monitored as control measurement, then during the next 10 min monitoring was with a magnetic field switched on, followed by a period of 5 min with the field switched off. A variety of exposure conditions have been tested: the frequency was varied between 5 and 1000 Hz, the field strength was varied up to 2.7 mT, different pulse shapes were used, the influence of the exposure temperature was tested, and the influence of the optimum exposure conditions (static magnetic field and the frequency of the dynamic field) as predicted by the ion parametric resonance (IPR) model has been measured. In conclusion, in no case any statistical significant influence of the magnetic treatment on the oscillation frequency of the BZ reaction could be detected (P > .05, t‐test). Bioelectromagnetics 27:314–319, 2006. © 2006 Wiley‐Liss, Inc.
Measurement of intracellular metabolites of primary metabolism and adenine nucleotides in chemostat cultivated Penicillium chrysogenum
Authors: Nasution U. , van Gulik W.M. , Kleijn R.J. , van Winden W.A. , Proell A. , Heijnen J.J.
Published: March 2006

An experimental platform has been developed for rapid sampling and quenching of chemostat cultivated Penicillium chrysogenum broth for metabolome analysis in highly dynamic experiments, aimed at the elucidation of the in vivo kinetic properties of metabolism. The sampling and quenching protocol available from Saccharomyces cerevisiae had to be modified for Penicillium chrysogenum mainly because of its filamentous character. Intracellular metabolites of glycolysis, TCA cycle, and adenine nucleotides were measured with isotope dilution mass spectrometry (IDMS) using a U‐13C‐labeled metabolite mix produced from yeast cells as internal standard. By addition of the U‐13C internal standard mix prior to the metabolite extraction procedure, partial degradation of metabolites as well as non‐linearity and drift of the LC‐MS/MS could be successfully compensated for. It was found that there is a serious matrix effect on metabolite extraction between different organisms, which is however completely corrected for by the IDMS approach. Intracellular metabolites could be analyzed with standard deviations of around 5%. A comparison of the metabolite levels between Saccharomyces cerevisiae and Penicillium chrysogenum showed both significant similarities and large differences, which seem to be related to the presence of the penicillin pathway. © 2006 Wiley Periodicals, Inc.
A review of determinant factors of environmental proactivity
Authors: González‐Benito Javier , González‐Benito Óscar
Published: March 2006

This paper reviews the literature in order to identify the determinant factors of a company's environmental proactivity. It starts by arguing that environmental proactivity can be manifested through diverse practices and strategies and goes on to comment upon several variables that seem to influence the decision to implement such strategies. Some of these variables depict internal company features and others describe the general environment in which operations are carried out. Stakeholders' pressure is distinguished as a central determinant factor and it is argued that all the other variables affect either the intensity of this pressure or the company's capacity to perceive it. All the factors identified herein should be taken into account, at least as control variables, in those studies aiming at explaining and contextualizing environmental strategies. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment.