bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eucalyptus Tar Pitch Substitution of Phenol in the Preparation of Novolak-Type Resins Cured with Hexamethylenetetramine
Authors: Pasa Vânya M D , Assis Rodrigo S , Bruns Roy E , dos-Santos Cláudio G 
Published: November 2008

Abstract
Wood tar pitch, sometimes referred to as biopitch, is the residue from the distillation of tar recovered during charcoal making processes. The biopitch from Eucalyptus tar, which has guaiacyl and syringyl units in its molecular structure, exhibits novolak behavior and this phenolic oligomer can be cured with hexamethylenetetramine (HMTA). In this work, mixtures of commercial phenolic resins and Eucalyptus tar pitch were cured and characterized by infrared spectroscopy, elemental and thermogravimetric analyses. Their acetone-insoluble contents were determined and their electrical properties were investigated. The effects of pitch and HMTA contents on phenolic resin properties were modelled using statistical techniques. The regions of optimum formulations were indicated. The results showed that pitch decreases the thermal stability and the acetone-insoluble content of the phenolic blends, whereas HMTA addition had an opposite effect. The statistical model applied indicated that, in terms of acetone-insoluble content, phenolic resin can be substituted for pitch up to a composition of 50 wt %. Electrical studies showed that pitch–phenolic blends have insulating properties.
Measurement of Very Low Creep Strains: A Review
Authors: Kloc Luboš , Mareček Petr 
Published: November 2008

Abstract
Various experimental techniques using mechanical springs for high strain sensitivity creep testing are described. A theory of stress and strain using these techniques is briefly summarized. Problems and advantages of the helicoid spring specimen technique are also analyzed. The helicoid spring specimen technique provides high efficiency for low-stress creep experiments in the self-loaded mode, while the external load mode allows extraordinary strain sensitivity. A new machine for conducting high-sensitivity torsion creep tests is presented together with some examples of creep curves obtained by the technique. The machine was designed to enable high sensitivity creep tests of inherently brittle materials such as intermetallics and ceramics.
Instrumented Impact Tests: Effects of Machine Variables and Specimen Position
Authors: Lucon Enrico , McCowan Chris N. , Santoyo Raymond L. 
Published: November 2008

Abstract
An investigation has been conducted on the influence of impact machine variables and specimen positioning on characteristic forces and absorbed energies from instrumented Charpy tests. Brittle and ductile fracture behavior has been investigated by testing NIST reference samples of low-, high-, and super-high-energy levels. Test machine variables included tightness of foundation, anvil and striker bolts, and the position of the center of percussion with respect to the center of strike. For specimen positioning, we tested samples that had been moved away or sideways with respect to the anvils. In order to assess the influence of the various factors, we compared mean values in the reference (“unaltered”) and “altered” conditions; for machine variables, t-test analyses were also performed in order to evaluate the statistical significance of the observed differences. Our results indicate that the only circumstance which resulted in variations larger than 5 % for both brittle and ductile specimens is when the sample is not in contact with the anvils. This should be taken into account in future revisions of instrumented Charpy test standards.
Impaired islet turnover in human donor pancreata with aging
Authors: Reers Christina , Erbel Saskia , Esposito Irene , Schmied Bruno , Büchler Markus W , Nawroth Peter P , Ritzel Robert A 
Published: November 2008

ObjectiveThe prevalence of type 2 diabetes mellitus escalates with aging although β-cell mass, a primary parameter of β-cell function, is subject to compensatory regulation. So far it is unclear whether the proliferative capacity of pancreatic islets is restricted by senescence.Materials and methodsHuman pancreatic tissue from n=20 non-diabetic organ donors with a mean age of 50.2±3.5 years (range 7–66 years) and mean body mass index of 25.7±0.9 kg/m2 (17.2–33.1 kg/m2) was morphometrically analyzed to determine β-cell volume, β-cell replication, β-cell apoptosis, islet neogenesis, and pancreatic duodenal homeobox-1 (PDX-1) expression.ResultsRelative β-cell volume in human pancreata (mean 2.3±0.2%) remains constant with aging (r=0.26, P=ns). β-cell replication (r=0.71, P=0.0004) decreases age-dependently, while β-cell apoptosis does not change significantly (r=0.42, P=0.08). Concomitantly, PDX-1 expression is downregulated with age in human pancreatic tissue (r=0.65, P=0.002). The rate of islet neogenesis is not affected by aging (r=0.13, P=ns).ConclusionsIn non-diabetic humans, aging is linked with impaired islet turnover possibly due to reduced PDX-1 expression. As β-cell replication is considered to be the main mechanism responsible for β-cell regeneration, these changes restrict the flexibility of the aging human pancreas to adapt to changing demands for insulin secretion and increase the risk for the development of diabetes mellitus in older subjects.
Exergy of nuclear radiation — a quantum statistical thermodynamics approach
Authors: Badescu Viorel 
Published: November 2008

Abstract
The exergy of nuclear radiation is evaluated by using a simple quantum statistical thermodynamic approach. Only radiation particles with non-zero rest mass are considered (i.e. protons, neutrons, alpha and beta particles). The exergy and the exergy flux involve efficiency-like factors affecting the internal energy and the energy flux, respectively. These factors are generally different from both the usual Carnot factor and the Petela-Landsberg-Press factor that appears in the exergy of blackbody radiation. The efficiency-like factors are higher in the case of charged rather than neutral particles and in the case of enclosed rather than free radiation. The results are compared with those obtained previously by using a classical thermodynamic theory.
Effect of fluorination of molecular rigid core in liquid crystal biphenyl benzoate based homologous series
Authors: Morawiak P. , Piecek W. , Żurowska M. , Perkowski P. , Raszewski Z. , Dąbrowski R. , Czupryński K. , Sun X.W. 
Published: November 2008

AbstractLiquid crystalline perfluorinated biphenyl benzoates were synthesized and investigated. A highly tilted, neat orthoconic smectic antiferroelectric phase was observed. A homologous series of compounds without and with a single fluorine atom substituted at different positions of a molecular rigid core was investigated by standard methods. Influence of fluorine substitution on physical properties of antiferroelectric smectic phase was discussed as well as influence of fluorination on molecular dipole moment orientation and its value were presented. Decrease in rotational viscosity as a result of fluorine substitution within a molecular rigid core was ascribed to changes of molecular packing.
Molecular Characterization of Hemophilia a in Southeast Bulgaria
Authors: Sukarova Stefanovska E , Tchakarova P , Petkov G , Efremov G 
Published: November 2008

Molecular Characterization of Hemophilia a in Southeast BulgariaThe results of molecular characterization of Hemophilia A in 50 patients from Southeast Bulgaria are presented. Southern blot analysis for the detection of inversions in intron 22, and polymerase chain reaction (PCR) followed by single strand conformation polymorphism (SSCP) or de-naturing gradient gel electrophoresis (DGGE) for screening of the coding sequences of the Factor VIII (FVIII) gene were used. A molecular defect was found in 35 (70%), the most frequent being an inversion in intron 22, found in 19 (38%) patients; an intron 1 inversion was not detected. In one severely affected patient, an Alu insert was found, which disrupted exon 14 at codon 1224. Nucleotide substitutions were found in 15 (30%) patients, the most frequent being an Arg531→Cys missense mutation in exon 11. The same nonsense mutation (codon -5,CGA>TGA) was found in two patients with a severe phenotype. Seven missense mutations (Asn90→Thr, Arg 372→His, Glu456→Val, Tyr473→His, Arg1689→ Cys, Arg2159→Cys and Arg2163→His) were detected in isolated families. Two of these (Asn90→Thr and Glu456→ Val) are being reported for the first time.
Investigation of the Frequency and Force of Chest Vibration Performed by Physiotherapists
Authors: Li S.K. , Silva Y.R. 
Published: November 2008

Purpose: To investigate the frequency and force of chest vibration as applied by 18 physiotherapists working in a teaching hospital. Method: Chest vibration was applied to a healthy adult male lying supine on a plinth with seven mounted sensors measuring frequency and force, during three test conditions: (1) directly on the chest, (2) on the chest through a layer of sheet, and (3) on the chest through a layer of towelling. The influence of gender and current practice area (physiotherapists working in cardiopulmonary areas [cardiopulmonary physiotherapists] and physiotherapists who presently did not work in the cardiopulmonary area, but had treated cardiopulmonary patients within the last year [general practice physiotherapists]) on the frequency and force of chest vibrations was examined. Results: Physiotherapists demonstrated a mean frequency of 5.7, 5.3, and 5 Hz and a mean maximum force of 272.78, 273.47, and 271.13 N for conditions 1, 2, and 3 respectively. There were no significant differences in the frequency or forces generated by vibration between cardiopulmonary and general practice physiotherapists, between genders, or among the three test conditions. Conclusions: Vibration frequency was lower and force higher than previously recorded. Force may vary depending on the patient. The addition of a sheet or towel did not affect the force or frequency of vibration compared to vibration performed directly on the chest.
Perceptions of Outpatients Regarding the Attire of Physiotherapists
Authors: Mercer Erin , MacKay-Lyons Marilyn , Conway Nicki , Flynn Jennifer , Mercer Chris 
Published: November 2008

Purpose: This study investigated perceptions of patients regarding physiotherapists’ attire. Methods: Three hundred patients in three publicly funded outpatient physiotherapy clinics were asked to complete a questionnaire, ranking four photographed modes of attire (lab coat, tailored dress, “scrubs,” and jeans) in terms of professionalism, preference, and appropriateness and rating their level of agreement with four statements about physiotherapists’ attire. Results: Response rate was 63.7 %. The lab coat was ranked most professional, tailored dress most preferred, and jeans least professional and least preferred. Although jeans were deemed inappropriate (p < 0.001), strong support was shown for wearing jeans on “casual day” (p = 0.001). Age of respondents influenced the perception of the appropriateness of wearing jeans (p = 0.007 for male therapist; p = 0.017 for female therapist); only the cohort <36 years considered jeans appropriate apparel. Overall exposure to physiotherapists (number of lifetime visits) affected patients’ perceptions of the importance of attire (p = 0.039) and the appropriateness of wearing jeans (p = 0.018): as number of visits increased, perceived importance decreased and perceived propriety of jeans increased. Conclusion: The findings of this study, the first to examine patients’ opinions of physiotherapists’ attire, suggest that outpatients made clear distinctions between what they perceived as professional and what they preferred, as well as between the appropriateness of physiotherapists’ wearing jeans in general and the appropriateness of their doing so on “casual day.” Age and exposure to physiotherapists influenced patients’ perceptions of attire.
Exercise for Fall Risk Reduction in Community-Dwelling Older Adults: A Systematic Review
Authors: Arnold Catherine M. , Sran Meena M. , Harrison Elizabeth L. 
Published: November 2008

Purpose: To evaluate the influence of exercise on falls and fall risk reduction in community-dwelling older adults and to present an updated synthesis of outcome measures for the assessment of fall risk in community-dwelling older adults. Method: A systematic review was performed, considering English-language articles published from 2000 to 2006 and accessible through MEDLINE, CINAHL, PEDro, EMBASE, and/or AMED. Included were randomized controlled clinical trials (RCTs) that used an exercise or physical activity intervention and involved participants over age 50. Screening and methodological quality for internal validity were conducted by two independent reviewers. Results: The search retrieved 156 abstracts; 22 articles met the internal validity criteria. Both individualized and group exercise programmes were found to be effective in reducing falls and fall risk. The optimal type, frequency, and dose of exercise to achieve a positive effect have not been determined. A variety of outcome measures have been used to measure fall risk, especially for balance. Conclusions: Falls and fall risk can be reduced with exercise interventions in the community-dwelling elderly, although the most effective exercise variables are unknown. Future studies in populations with comorbidities known to increase fall risk will help determine optimal, condition-specific fall-prevention programmes. Poor balance is a key risk factor for falls; therefore, the best measure of this variable should be selected when evaluating patients at risk of falling.
Construct Validity and Reliability of the Disability ofArm, Shoulder and Hand Questionnaire for Upper Extremity Complaints in Rheumatoid Arthritis
Authors: RAVEN ERIC E.J. , HAVERKAMP DANIËL , SIEREVELT INGER N. , van MONTFOORT DOUWE O. , PÖLL RUUD G. , BLANKEVOORT LEENDERT , TAK PAUL P. 
Published: November 2008

ObjectiveThe Disability of Arm, Shoulder and Hand (DASH) questionnaire is a tool for measuring physical function and symptoms of the upper extremity. Although widely used, it is not validated for rheumatoid arthritis (RA). In this study the DASH was validated for this patient group.MethodsIn total, 102 patients participated in this study. For the validation, the questionnaires of the DASH, the Health Assessment Questionnaire (HAQ), the Medical Outcomes Study Short Form-36 (SF-36), and the Arthritis Impact Measurement Scale (AIMS2) were used. Patients were examined clinically before completing the questionnaires. Pain was scored by each patient using a visual analog scale (VAS). The DiseaseActivity Score (DAS28) was obtained and grip strength was measured. Reliability was tested by a second DASH questionnaire after 2 days. Validity was tested using a Pearson correlation analysis for the relevant domains of the questionnaires and for the clinical aspects.ResultsThe reliability of the DASH was excellent (intraclass correlation coefficient 0.97). Internal consistency was strong (Cronbach’s alpha 0.97). Validity was proven with excellent results for Pearson correlation with the relevant domains of the questionnaires: HAQ, r = 0.88; SF-36, r = 0.70; and AIMS2, r = 0.85. The clinical scores had a relatively low correlation with the DASH (DAS28, r = 0.42; and grip strength, r = 0.41–0.48), except for the VAS (r = 0.60–0.65).ConclusionThe DASH is a reliable and valid questionnaire in patients with RA. It can be used as a measurement tool of physical disability of the upper extremity.
Predicting Patient Dissatisfaction Following Joint Replacement Surgery
Authors: GANDHI RAJIV , DAVEY J. RODERICK , MAHOMED NIZAR N. 
Published: November 2008

ObjectiveThe incidence of patient-reported dissatisfaction following total joint arthroplasty can be up to 30%. Our aim was to identify the preoperative patient-level predictors of patient dissatisfaction 1 year after surgery.MethodsWe surveyed 1720 patients undergoing primary hip or knee replacement surgery. Relevant covariates including demographic data, body mass index, sex, comorbidities, and education were recorded. Joint functional status and patient quality of life were assessed at baseline and at 1-year followup with the Western Ontario McMaster University Osteoarthritis Index (WOMAC) and Medical Outcomes Study Short Form-36 (SF-36) scales, respectively. Patient satisfaction with surgery was determined with 4 survey questions at 1-year followup.ResultsThere were no significant differences in demographic data between satisfied (n = 1290) and dissatisfied patients (n = 430). Logistic regression modeling showed that a lower preoperative SF-36 Mental Health score independently predicted patient dissatisfaction with surgery, adjusted for all relevant covariates (p < 0.05). We found no correlation between patient satisfaction and WOMAC change scores at 1-year followup (p = 0.31).ConclusionPreoperative mental health is an important factor to consider when understanding patient satisfaction with surgery. Interventions to reduce psychological distress prior to surgery should be studied to determine if they may improve subjective outcomes of patients undergoing joint replacement surgery.
Elevated Serum Insulin-like Growth Factor (IGF-1) and IGF Binding Protein-3 Levels in Patients with Systemic Sclerosis: Possible Role in Development of Fibrosis
Authors: HAMAGUCHI YASUHITO , FUJIMOTO MANABU , MATSUSHITA TAKASHI , HASEGAWA MINORU , TAKEHARA KAZUHIKO , SATO SHINICHI 
Published: November 2008

ObjectiveTo examine serum concentrations of insulin-like growth factor (IGF-1) and IGF binding protein (IGFBP-3), a major carrier protein for IGF-1, in patients with systemic sclerosis (SSc); and to relate the results to clinical features in SSc.MethodsSerum IGF-1 and IGFBP-3 levels in 92 Japanese patients with SSc were measured by ELISA. Expression of IGF-1 and IGFBP-3 messenger RNA (mRNA) in the skin was quantified by real-time reverse transcription-polymerase chain reaction.ResultsSerum IGF-1 and IGFBP-3 levels were significantly elevated in patients with SSc compared with patients with systemic lupus erythematosus or healthy controls. IGF-1 levels were higher in patients with diffuse cutaneous SSc (dcSSc) than in patients with limited cutaneous SSc (lcSSc). Patients with increased IGF-1 levels had more severe skin involvement and pulmonary fibrosis. IGF- 1 mRNA was upregulated in the affected skin of patients with SSc. There were no significant differences in serum IGFBP-3 levels between dcSSc and lcSSc. IGFBP-3 levels were not associated with skin thickness and pulmonary fibrosis. Patients with increased IGF-1 or IGFBP-3 had lower frequency of telangiectasia than patients with normal levels.ConclusionThese results suggest that both IGF-1 and IGFBP-3 are involved in the development of SSc. The role of IGF-1 appears to be different from that of IGFBP-3.
Setting a public health research agenda for Down syndrome: Summary of a meeting sponsored by the Centers for Disease Control and Prevention and the National Down Syndrome Society
Authors: Rasmussen Sonja A. , Whitehead Nedra , Collier Sarah A. , Frías Jaime L. 
Published: November 2008

AbstractOn November 8–9, 2007, a meeting entitled “Setting a Public Health Research Agenda for Down Syndrome” was held to review current knowledge, identify gaps, and develop priorities for future public health research related to Down syndrome. Participants included experts in clinical and molecular genetics, pediatrics, cardiology, psychiatry, psychology, neuroscience, epidemiology, and public health. Participants were asked to identify key public health research questions and discuss potential strategies that could be used to address those questions. The following were identified as priority areas for future public health research: identification of risk and preventive factors for physical health and cognitive outcomes, focusing on understanding the reasons for previously recognized disparities; improved understanding of comorbid conditions, including their prevalence, clinical variability, natural history, and optimal methods for their evaluation and treatment; better characterization of the natural history of cognition, language, and behavior; identification of mental health comorbidities and of risk and protective factors for their development; identification of strategies to improve enrollment in research studies; development of strategies for conveying up‐to‐date information to parents and health professionals; identification of interventions to improve cognition, language, mental health, and behavior; understanding the impact of educational and social services and supports; identification of improved methods for diagnosis of and interventions for Alzheimer disease; and understanding the effects of different types of health care on outcomes. Participants strongly supported the development of population‐based resources for research studies and resources useful for longitudinal studies. This agenda will be used to guide future public health research on Down syndrome. Published 2008 Wiley‐Liss, Inc.
Social influence on predictions of simulated stock prices
Authors: Andersson Maria , Hedesström Ted Martin , Gärling Tommy 
Published: November 2008

AbstractHerding in financial markets refers to that investors are influenced by others. This study addresses the importance of consistency for herding. It is suggested that, in financial markets perceptions of consistency are based on repeated observations over time. Consistency may then be perceived as the agreement across time between investors' predictions. In addition, consistency may be related to variance over time in each investor's predictions. In an experiment using a Multiple Cue Probability Learning paradigm, 96 undergraduates made multi‐trial predictions of future stock prices given information about the current price and the predictions made by five fictitious others. Consistency was varied between the others' predictions (correlation) and within the others' predictions (variance). The results showed that the predictions were significantly influenced by the others' predictions when these were correlated. No effect of variance was observed. Hence, participants were influenced by the others when they were in agreement, regardless of whether they varied their predictions over trials or not. Copyright © 2008 John Wiley & Sons, Ltd.
Fracture of a GORE HELEX Septal Occluder following PFO closure in a diver
Authors: Scott Paul , Wilson Neil , Veldtman Gruchen 
Published: November 2008

AbstractDecompression illness (DCI) is more common in divers with a patent foramen ovale (PFO), and transcatheter PFO closure is being increasingly performed in patients with an episode of DCI who want to continue diving. A range of closure devices are available and the choice in an individual case depends on operator preference and PFO anatomy. The GORE HELEX Septal Occluder, introduced in 1999 primarily for secundum atrial defect closure, is a compliant non self‐centering device composed of a wire helical framework on which a microporous membrane is mounted. The device is fixed in place by a unique interlocking mechanism that passes through the center of the device from the left to the right atrial disc, thereby securing it onto the interatrial septum. Here, we present a case of a locking loop fracture and review the literature concerning this unusual complication. © 2009 Wiley‐Liss, Inc.