bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermally conductive carbon filled nylon 6,6
Authors: Heiser Jessica A. , King Julia A. 
Published: April 2004

AbstractIncreasing the thermal conductivity of typically insulating polymers, such as nylon 6,6, opens new markets. A thermally conductive resin can be used for heat sink applications. This research focused on performing compounding runs followed by injection molding and through‐plane thermal conductivity testing of carbon filled nylon 6,6 based resins. The three carbon fillers investigated included an electrically conductive carbon black, synthetic graphite particles, and a surface treated polyacrylonitrile (PAN) based carbon fiber. Conductive resins were produced and tested that contained varying amounts of these single carbon fillers. In addition, combinations of fillers were investigated by conducting a full 23 factorial design and a complete replicate. The objective of this paper was to determine the effects and interactions of each filler on the thermal conductivity of the resins. Synthetic graphite particles caused the largest increase in composite thermal conductivity. In addition, all the single fillers and combinations of fillers caused a statistically significant (at the 95% confidence level) increase in composite thermal conductivity. Polym. Compos. 25:186–193, 2004. © 2004 Society of Plastics Engineers.
A potential bias in safety evaluation during open‐label extensions of randomized clinical trials
Authors: Rothman Kenneth J. 
Published: April 2004

AbstractPurposeTo describe a bias that can occur in the analysis of data from certain randomized trials.Methods and ResultsAlthough randomized trials are effective at preventing confounding, a potentially strong confounding can arise in certain therapeutic drug trials in which follow‐up is extended in an open‐label phase that allows switching treatments. Many trials implement eligibility screening that excludes those at high risk of morbidity and mortality. In these trials, disease rates and death rates for the study population can rise rapidly during follow‐up as the effect of screening wanes. During the open‐label follow‐up, a preponderance of patients may switch to the new therapy. If so, then any evaluation of the new therapy that includes follow‐up from the open‐label phase, as is often the case for safety evaluations, will be confounded. The confounding arises because the person‐time experience of those on the new treatment will be more heavily weighted with the open‐label phase experience, during which morbidity and mortality rates may be much greater than in the initial phase of follow‐up. This confounding may be strong and will be in the direction of making the new treatment look worse, provided that the net switching is toward the new treatment during the open‐label phase.ConclusionsThe confounding described here is not prevented by randomization because it develops in a non‐randomized add‐on analysis to the trial. The bias can be removed, however, by controlling for time since randomization in the analysis of the data. Copyright © 2004 John Wiley & Sons, Ltd.
Mechanism of preparing monodisperse poly(acrylamide/methacrylic acid) microspheres in ethanol. I
Authors: Ni Henmei , Kawaguchi Haruma 
Published: April 2004

AbstractThe precipitation polymerization of acrylamide/methacrylic acid (AAm/MAA) in ethanol (EtOH) was thoroughly investigated from detecting the homogeneity of the initial solution prior to polymerizations to the final products of the polymerizations. Dynamic light scattering and scanning electron microscopy were employed for the investigations. The solutions of AAm and AAm/acrylic acid (AAm/AA) were homogeneous. However, the solutions of AAm/MAA, AAm/poly(MAA) (PMAA), and AAm/poly(AA) (PAA) were not homogeneous as they are usually considered to be: entities with size distributions of around 150, 40, and 17 nm, respectively, were detected at the polymerization temperature of 60 °C. Accordingly, analogous to the entities that are similar to the structure of micelles formed in the solutions of AAm/PMAA and AAm/PAA because of polymer–AAm interactions, it was suggested that the complexes of AAm/MAA stemming from the molecular interactions, particularly the (lypo‐) hydrophobic interaction, aggregated to form minimonomer droplets at 60 °C. The monodisperse microspheres were prepared only in the AAm/MAA‐EtOH systems, whereas the microspheres were not prepared in the homogeneous AAm‐EtOH systems despite the precipitation of PAAm. The results obtained from various polymerizations showed that the microspheres originated from the polymerization within the minimonomer droplets. A new mechanism was established that describes the processes for the formation of all products possibly generated in the AAm‐MAA‐EtOH polymerization system. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2823–2832, 2004
Atom transfer radical polymerization of methyl methacrylate by copper(I)‐pyridine‐2‐carboximidate catalysts
Authors: Lee Do W. , Seo Eun Y. , Cho Sung I. , Yi Chae S. 
Published: April 2004

AbstractPyridine‐2‐carboximidates [methyl (1a), ethyl (1b), isopropyl (1c), cyclopentyl (1d), cyclohexyl (1e), n‐octyl (1f), and benzyl (1g)] were prepared from the reaction of 2‐cyanopyridine with the corresponding alcohols. Cyclopentyl‐substituted 1d was found to be a highly effective ligand for copper‐catalyzed atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA). For example, the observed rate constant for a CuBr/1d catalytic system was found to be nearly twice as high as the cyclohexyl‐substituted CuBr/1e catalytic system [kobs = (1.19 vs 0.56) × 10−4 s−1). The effects of the solvents, temperature, catalyst/initiator, and solvent/monomer ratio on the ATRP of MMA were studied systematically for the CuBr/1d catalytic system. The optimum condition for the ATRP of MMA was found to be a 1:2:1:400 [CuBr]o/[1d]o/[ethyl 2‐bromoisobutyrate]o/[MMA]o ratio at 60 °C in veratrole solution, which yielded well‐defined poly(MMA) with a narrow molecular weight distribution of 1.14. The catalytically active copper complex 2d was isolated from the reaction of CuBr with 1d. Narrow molecular weight distributions as low as 1.06 were achieved for the CuBr/1d catalytic system by employing 10% of the deactivator CuBr2. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2747–2755, 2004
A Constant‐Density Gurney Approach to the Cylinder Test
Authors: Reaugh John E. , Souers P. Clark 
Published: April 2004

AbstractThe previous analysis of the Cylinder test required the treatment of different wall thicknesses and wall materials separately. To fix this, the Gurney analysis is used, but this results in low values for full‐wall standard, ideal explosives relative to CHEETAH analyses. A new constant metal‐density model is suggested, which takes account of the thinning metal wall as the cylinder expands. With this model, the inner radius of the metal cylinder moves faster than the measured outer radius. Additional small corrections occur in all cylinders because of energy trapped in the copper walls. Also, the half‐wall cylinders have a small correction because the relative volumes of the gas products are smaller at a given outside wall displacement. The Fabry‐Perot and streak camera measurements are compared. The Fabry method is shown to equate to the constant density model.
Development and large scale benchmark testing of the PROSPECTOR_3 threading algorithm
Authors: Skolnick Jeffrey , Kihara Daisuke , Zhang Yang 
Published: April 2004

AbstractThis article describes the PROSPECTOR_3 threading algorithm, which combines various scoring functions designed to match structurally related target/template pairs. Each variant described was found to have a Z‐score above which most identified templates have good structural (threading) alignments, Zstruct (Zgood). ‘Easy’ targets with accurate threading alignments are identified as single templates with Z > Zgood or two templates, each with Z > Zstruct, having a good consensus structure in mutually aligned regions. ‘Medium’ targets have a pair of templates lacking a consensus structure, or a single template for which Zstruct < Z < Zgood. PROSPECTOR_3 was applied to a comprehensive Protein Data Bank (PDB) benchmark composed of 1491 single domain proteins, 41–200 residues long and no more than 30% identical to any threading template. Of the proteins, 878 were found to be easy targets, with 761 having a root mean square deviation (RMSD) from native of less than 6.5 Å. The average contact prediction accuracy was 46%, and on average 17.6 residue continuous fragments were predicted with RMSD values of 2.0 Å. There were 606 medium targets identified, 87% (31%) of which had good structural (threading) alignments. On average, 9.1 residue, continuous fragments with RMSD of 2.5 Å were predicted. Combining easy and medium sets, 63% (91%) of the targets had good threading (structural) alignments compared to native; the average target/template sequence identity was 22%. Only nine targets lacked matched templates. Moreover, PROSPECTOR_3 consistently outperforms PSIBLAST. Similar results were predicted for open reading frames (ORFS) ≤200 residues in the M. genitalium, E. coli and S. cerevisiae genomes. Thus, progress has been made in identification of weakly homologous/analogous proteins, with very high alignment coverage, both in a comprehensive PDB benchmark as well as in genomes. Proteins 2004;55:000–000. © 2004 Wiley‐Liss, Inc.
Negative ion electrospray ionization mass spectral study of dicarboxylic acids in the presence of halide ions
Authors: Kumar M. Ravi , Prabhakar S. , Kumar M. Kiran , Reddy T. Jagadeshwar , Vairamani M. 
Published: April 2004

AbstractThe negative ion electrospray ionization (ESI) mass spectra of a series of dicarboxylic acids, a pair of isomeric (cis/trans) dicarboxylic acids and two pairs of isomeric (positional) substituted benzoic acids, including a pair of hydroxybenzoic acids, were recorded in the presence of halide ions (F−, Cl−, Br− and I−). The ESI mass spectra contained [MH]− and [M+X]− ions, and formation of these ions is found to be characteristic of both the analyte and the halide ion used. The analytes showed a greater tendency to form adduct ions with Cl− under ESI conditions compared with the other halide ions used. The isomeric compounds yielded distinct spectra by which the isomers could be easily distinguished. The collision‐induced dissociation mass spectra of [M+X]− ions reflected the gas‐phase basicities of both the halide ion and [MH]− ion of the analyte. However, the relative ordering of gas‐phase basicities of all analyte [MH]− and halide ions could not account for the dominance of chloride ion adducts in ESI mass spectra of the analytes mixed with equimolar quantities of the four halides. Copyright © 2004 John Wiley & Sons, Ltd.
Pyoderma Gangrenosum with a Contiguous Erosion of the Distal Ulna
Authors: Hayes Robert C. , Curtis Anne 
Published: April 2004

Background Pyoderma gangrenosum (PG) has been described in association with sterile neutrophilic infiltration of several organ systems, including the skeleton. The most frequent cause of bony disease in PG has been chronic, recurrent, multifocal osteomyelitis, a sterile inflammatory disease of children and young adults mimicking infectious osteomyelitis. Bony erosions have been only rarely described in direct contiguity to a PG ulcer. Objective We report a 53-year-old woman with recurrent PG who developed an erosion of the distal ulna adjacent to a PG ulcer. The patient responded to high-dose prednisone, and a repeat radiograph of the wrist four months later was normal. Conclusion This case demonstrates another example of cortical osteolysis directly adjacent to a PG ulcer in which the bony changes may be neutrophil-induced.
Student Research Award 1998: Cytokine‐mediated bone resorption is cytochrome P‐450 dependent
Authors: Young Nwanmegha , Chole Richard 
Published: April 2004

Localized bone loss leads to much of the morbidity of chronic otitis media. Although the cellular events of bone remodeling have been well established, their regulation remains Poorly understood. Various cytokines, including tumor necrosis factor‐α, interleukin‐1β, and interferon‐γ, used alone and in combination, are Powerful inducers of bone resorption. One of the modulators of cytokine‐induced bone resorption is nitric oxide (NO), a product of the action of NO synthase (NOS) on L‐arginine to form NO. Cytochrome P‐450, an enzyme that is similar to NOS both structurally and functionally, may also have a role in NO production in various cellular systems. The goal of this study was to elucidate a Possible role of cytochrome P‐450 in bone. In this study cytokine‐induced bone resorption was blocked with cimetidine and clotrimazole, which are selective inhibitors of the cytochrome P‐450 IIIA family and 7‐ethoxyresorufin, a nonspecific cytochrome P‐450 inhibitor. A concomitant reduction of NO was also observed. This effect may be explained by cytochrome P‐450 being a preferred alternative pathway or providing an essential cofactor to NOS in bone.
Recollections of Patrick Blackett 1945-70
1
Authors: Butler C. 
Published: April 2004

The author was privileged to work closely with Patrick Blackett from 1945 over a continuous period of 25 years, first at Manchester University and later at Imperial College, London.
In 1945, Blackett returned to Manchester determined to build up his Department of Physics, both undergraduate numbers and the volume of research. He believed passionately that in Britain a satisfactory and effective volume of research in a department could only be achieved if the number of capable undergraduates was much larger than in most pre-war physics departments. Furthermore, he believed the country was in need of more physics graduates. He exploited this belief relentlessly over the 25–year period.
In 1945, Blackett did not have a cut and dried action plan for his department, rather his ideas on how to achieve his purpose developed over time. Early on, however, he became concerned over the small number of professorships available. Pre-war, about 20% of physics staff were professors, but after the war this percentage gradually fell, reaching about 10% by the early 1960s. He took action to stem this trend in his own departments well before 1960.
Over the years Blackett realized he wanted to leave as his legacy a physics department with a wide spread of research expertise in physics and astronomy. If most of the individual research groups in his department were to make the impact he wanted on the world physics scene, then the overall size of the department was inevitably large, compared with the national average.
Without doubt Patrick Blackett made a very significant contribution to the wellbeing and development of physics in Britain, well beyond the bounds of Manchester and Imperial College.
Homogeneity of the Prion Protein Gene in Various European and Asian Pig Breeds
Authors: Lipp O. , Ritzmann M. , Kixmöller M. , Heinritzi K. , Hensel A. , Truyen U. 
Published: April 2004

SummaryThe genetic variability of the prion protein gene influences the susceptibility to infection with transmissible spongiform encephalopathy (TSE) agents in mice, sheep and possibly man. Pigs have been shown to be susceptible to the bovine spongiform encephalopathy (BSE) agent after intracerebral, but not after oral inoculation. In these studies, however, only a very limited number of pigs of a restricted genetic background were used. Therefore, the question arose whether those experiments do reflect the susceptibility of the species pig or rather that of a single possibly resistant pig breed. The prion protein gene of a total of 66 pigs from 12 different breeds (2 × Deutsche Landrasse, 3 × Deutsches Edelschwein, 4 × Leicoma, 4 × Duroc, 11 × Pietrain, 6 × Large White, 9 × Hampshire, 2 × Belgische Landrasse, 8 × Schwäbisch Hällisches Schwein, 6 × Bunte Bentheimer, 7 × Chinesisches Meishan, 4 × Wildschwein (wild boar)) was amplified by PCR and directly sequenced. All sequences were found to be identical and identical to the published sequence (T. Martin, S. Hughes, K. Hughes, and M. Dawson Biochem. Biophys. Acta 1995; 1270: 211).
Artificial hybridization between Pitcairnia flammea and Pitcairnia corcovadensis (Bromeliaceae): analysis of the performance of parents and hybrids
Authors: RÔÇAS GISELLE , KLEIN DENISE E. , DE MATTOS EDUARDO A. 
Published: April 2004

AbstractThe genus Pitcairnia (Bromeliaceae) includes species that hybridize readily in nature and species that occur together, but do not hybridize. In natural populations of P. flammea and P. corcovadensis, floral traits did not reveal morphological intermediates between them. However, it is possible to obtain artificial hybrids. Thus, we aimed to characterize the morphology of F1 hybrids and evaluate the fitness of different hybrids and parental generations. In most of the morphological traits, the F1 hybrids were intermediate to their parents. With regard to the fitness of the F1 hybrids and backcrosses, some traits were intermediate whereas others were parental‐like. In the greenhouse, no post–zygotic barriers for hybrid formation were observed. Due to successful clonal propagation we suggest that hybrids that were eventually produced by a non‐specific pollinator which might persist and spread in nature.
A Continuity of Care Integrated Literature Review, Part 2: Methodological Issues
Authors: Sparbel Kathleen J.H. , Anderson Mary Ann 
Published: April 2004

Purpose: In Part 2 of this two‐part series, research designs, methods, and measurement of continuity of care are explored.Design: Qualitative, integrated literature review of a sample of 38 continuity of care nursing research articles published 1990–1995.Methods: Ganong's (1987) stages of the integrative literature research review process were followed. A data collection tool was designed and pilot tested, and rules for data analysis and interpretation were established. Research articles were systematically analyzed and reported using descriptive analysis.Findings: Results showed few nursing models, primarily convenience sampling and nonexperimental cross‐sectional study designs, varied data collection methods, and inadequate instrumentation. Measurement criteria were diverse and influenced by the perspectives of the measurer.Conclusions: Continuity of patient care was identified as a construct comprised of many related and tangential concepts in need of more sophisticated review. Recommendations for researchers are discussed.
Critical Care Nurses' Perceptions of DNR Status
Authors: Thibault‐Prevost Jocelyne , Jensen Louise A. , Hodgins Marilyn 
Published: April 2004

Purpose: To describe the perceptions of nurses regarding do‐not‐resuscitate (DNR) decisions in critical care settings.Design: A survey assessing knowledge, attitudes, and practices concerning DNR status was distributed to all critical care nurses who were registered with the provincial licensing body in Alberta, Canada, and held positions of staff nurse, educator, or manager.Methods: Four hundred and five surveys were completed and returned. Descriptive analyses were conducted.Findings: The term “DNR” was found to be ambiguous. The rationale for DNR orders were also not well articulated in practice. Although nurses believed that patients, families, and nurses should participate in DNR decisions, physicians were most often cited as being responsible for the decision.Conclusions: Documentation of a comprehensive patient treatment plan and awareness of the rationale for DNR designation are strategies suggested to help achieve desired patient care goals in critical care settings.
Risk Factors for Breast Cancer in Jordanian Women
Authors: Petro‐Nustas Wasileh , Norton Mary E. , Al‐Masarweh Issa 
Published: April 2004

Purpose: To investigate risk factors associated with breast cancer in Jordanian women.Design: Retrospective case‐control study based on data from the Jordanian Cancer Registry in 1996.Methods: One hundred women with breast cancer (cases) and 100 women without breast cancer (controls) were interviewed in their homes. A questionnaire was developed in Arabic to investigate the risk factors associated with breast cancer in Jordanian women.Findings: Bivariate analysis indicated significant differences between the cases and controls, including age of menarche and menopause, use of households' pesticides, stressful life events, and direct trauma to the breast. Logistic regression analysis indicated higher odds ratios for breast enlargement, irregular menstruation, use of hair dye, oral contraceptives, and fertility drugs.Conclusions: Significant differences in correlates of breast cancer were found between the cases and the controls.
Push and Pull Factors in International Nurse Migration
Authors: Kline Donna S. 
Published: April 2004

Purpose: To describe the push and pull factors of migration in relation to international recruitment and migration of nurses.Organizing Construct: Review of literature on nurse migration, examination of effects of donor and receiving countries, and discussion of ethical concerns related to foreign nurse recruitment.Findings: The primary donor countries are Australia, Canada, the Philippines, South Africa, and the United Kingdom (UK); the primary receiving countries are Australia, Canada, Ireland, the UK, and the United States (US). The effects of migration on donor countries include the loss of skilled personnel and economic investment; receiving countries receive skilled nurses to fill critical shortages with less economic investment. Ethical concerns include the potential for exploitation of foreign nurses.Conclusions: Nurses migrate to seek better wages and working conditions than they have in their native countries. Given the current conditions, developed countries continue to actively recruit foreign nurses to fill critical shortages. Migration is predicted to continue until developed countries address the underlying causes of nurse shortages and until developing countries address conditions that cause nurses to leave.
Building Capacity Through a Collaborative International Nursing Project
Authors: Ogilvie Linda , Allen Marion , Laryea Joanna , Opare Mary 
Published: April 2004

Purpose: To discuss: (a) physical, human, organizational, social, and cultural capital and (b) empowerment as two theoretical foundations for building capacity.Methods. These theoretical notions are examined in an analysis of a joint project between the Department of Nursing, University of Ghana and the Faculty of Nursing at the University of Alberta, Canada.Findings: Capacity for the management of international development projects was enhanced at both sites. Building capacity required mutual trust, tolerance of ambiguity, and a willingness to step into the unknown.
Couples' Views of the Effects of Natural Family Planning on Marital Dynamics
Authors: VandeVusse Leona , Hanson Lisa , Fehring Richard J. , Newman Amy , Fox Jaime 
Published: April 2004

Purpose: Natural Family Planning (NFP) requires periodic abstinence and partner cooperation to prevent pregnancy. The aim of this study was to learn about the effects of modern NFP methods on marital relationships.Design: Descriptive survey.Methods: Questionnaires were mailed to 1,400 randomly selected couples known to use NFP and residing in the United States of America; 334 couples (24%) responded. Content analysis was used to identify meanings and themes. Numeric analyses were used to determine frequencies.Findings: Nearly two‐thirds of the qualitative comments were positive. Four themes were identified in the positive responses: relationship enhancements, knowledge improvements, spirituality enrichments, and method successes. Three negative themes were identified: strained sexual interactions, worsened relationships, and method problems. Although about onefourth of the comments indicated that NFP presented challenges, the majority (74%) found it beneficial, often resulting in stronger bonds, better communication, and improved knowledge.Conclusions: NFP had more positive than negative effects and its use warrants further consideration.