bluuebunny/crossref_metadata_2025_split huggingface dataset:
New thermosets obtained by the cationic copolymerization of diglycidyl ether of bisphenol A with γ‐caprolactone with an improvement in the shrinkage. I. Study of the chemical processes and physical characteristics
Authors: González Servando , Fernández‐Francos Xavier , Salla Josep Maria , Serra Angels , Mantecón Ana , Ramis Xavier 
Published: April 2007

AbstractDiglycidyl ether of bisphenol A was cured with different proportions of γ‐caprolactone with ytterbium triflate as an initiator. The curing was studied by means of differential scanning calorimetry and Fourier transform infrared in the attenuated total reflection mode. The latter was used to monitor the competitive reactive processes and to quantify the conversions of the epoxide, lactone, and intermediate spiroorthoester groups. A partial depolymerization process from the cured material to free γ‐caprolactone was also identified. The formation of a stable carbocation and the coordinative capability of ytterbium triflate were the reasons for this unexpected process. The thermal and dynamic mechanical properties of the cured materials were determined with differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis. An increase in the proportion of γ‐caprolactone resulted in an increased curing rate, a decrease in the shrinkage after gelation, and a significant decrease in the glass transition temperature. The introduction of ester linkages into the three‐dimensional structure led to more thermally degradable thermosets. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1968–1979, 2007
Synthesis of a novel bis‐spiroorthoester containing 9,10‐dihydro‐9‐oxa‐10‐phosphaphenantrene‐10‐oxide as a substituent: Homopolymerization and copolymerization with diglycidyl ether of bisphenol A
Authors: Canadell J. , Mantecón A. , Cádiz V. 
Published: April 2007

AbstractA new bis‐spiroorthoester‐containing monomer, bis[(1,4,6‐trioxaspiro‐[4.4]‐nonan‐2‐yl)‐methyl] 2‐[10‐(9,10‐dihydro‐9‐oxa‐10‐phosphaphenantrene‐10‐oxide‐10‐yl)] maleate (SOE‐DOPOMA), was synthesized with good yields by an esterification reaction with a hydroxylated spiroorthoester (2‐hydroxymethyl‐1,4,6‐trioxaspiro‐[4.4]‐nonane) and a phosphorus‐containing diacid {2‐[10‐(9,10‐dihydro‐9‐oxa‐10‐phosphaphenantrene‐10‐ oxide‐10‐yl)] maleic acid}, both of which were previously synthesized. SOE‐DOPOMA was characterized with 1H, 13C, and 31P NMR spectroscopy. This new spiroorthoester was crosslinked with ytterbium triflate as a cationic initiator. A mixture of SOE‐DOPOMA and diglycidyl ether of bisphenol A was also crosslinked under the same conditions. The curing was studied with differential scanning calorimetry and monitored with Fourier transform infrared spectroscopy. The materials were characterized with differential scanning calorimetry, thermogravimetric analysis, and thermodynamomechanical analysis. The shrinkage effect on cationic crosslinking was assessed with gas pycnometry, and the flame‐retardant properties were determined with limiting oxygen index measurements. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1980–1992, 2007.
Specific swelling behaviors of alkali‐metal poly(styrene sulfonate) gels in aqueous solvent mixtures
Authors: Fukunaga Yoko , Hayashi Mariko , Satoh Mitsuru 
Published: April 2007

AbstractCounterion‐ and solvent‐specific swelling behaviors were investigated for alkali‐metal poly(styrene sulfonate) (PSSM) gels having different degrees of sulfonation in aqueous organic solvent mixtures [water plus methanol, ethanol, 2‐propyl alcohol, t‐butyl alcohol, dimethyl sulfoxide (DMSO), acetone, acetonitrile, tetrahydrofuran, or dioxane]. With an increasing organic solvent concentration, most gel systems, except for DMSO, showed a volume phase transition. The transition abruptly occurred without significant deswelling in the lower solvent concentration region. Such swelling behavior contrasted with that of other common charged gel systems, including alkali‐metal polyacrylate (PAAM) gels, which showed gel collapse after gradual deswelling with an increasing organic solvent concentration. The dielectric constant at the critical transition point (Dcr) for most mixed solvent systems decreased in the order of PSSK ≥ PSSCs ≥ PSSNa > PSSLi; that is, larger counterion systems were favorable for the transition. The counterion specificity also contrasted with our previous results for PAAM gels: PAANa > PAAK > PAALi ∼ PAACs. On the other hand, the solvent specificity for the PSSM gels was similar to that for the PAAM gels; the higher the dielectric constant was of the organic solvent, the higher the Dcr value was at which the transition occurred. These specificities were examined on the basis of the solvation properties of the counterions and polymer charged groups and the solvent properties such as the Gutmann–Mayer donor number and acceptor number. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1166–1175, 2007
Fractionated crystallization of polypropylene droplets produced by nanolayer breakup
Authors: Jin Y. , Hiltner A. , Baer E. 
Published: April 2007

AbstractLayer‐multiplying coextrusion was used to fabricate assemblies of 257 layers, in which polypropylene (PP) nanolayers alternated with thicker polystyrene (PS) layers. The PP layer thickness was varied from 12 to 200 nm. When the assembly was heated into the melt, interfacial instability‐driven breakup of the thin PP layers produced a dispersion of PP particles in a PS matrix. Particle size analysis indicated that breakup of PP microlayers produced a bimodal particle size distribution. A population of submicron particles formed because of the Rayleigh instability, and a second population of large particles formed by relaxation. Breakup of 12‐nm layers resulted in primarily submicron particles. The fraction of PP as submicron particles dropped dramatically as the layer thickness increased to 40 nm. The particle dispersion was characterized by thermal analysis and wide angle X‐ray diffraction. Fractionated crystallization gave rise to four crystallization exotherms at 40, 60, 85, and 100 °C. The exotherm at 40 °C was identified with homogeneous nucleation of the submicron particles in the smectic form. Exotherms at higher temperatures represented fractionated crystallization of the large micron‐sized particles in the PP α‐form. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 1138–1151, 2007
Supportive care of rural women with breast cancer in Tasmania, Australia: changing needs over time
Authors: Minstrell Melinda , Winzenberg Tania , Rankin Nicole , Hughes Clarissa , Walker Judi 
Published: April 2007

AbstractProviding for patients' psychosocial needs is a potential means of minimising cancer morbidity. Needs assessments can guide responsive patient‐centred care. A longitudinal survey of women with early breast cancer consulting a breast nurse in a primarily rural state of Australia was undertaken to measure unmet supportive care needs, identify changes in unmet needs across time and compare results with previous studies. Needs assessments were completed with the Supportive Care Needs Survey (SCNS) at 1 month (n = 74) and 3 months (n = 83) post‐diagnosis. Access to services was also examined. High levels of psychological and health system and information needs were identified at 1 month post‐diagnosis, but these decreased significantly at 3 months post‐diagnosis. Sexuality domain needs increased significantly during the same time. Compared to a previous SCNS study of rural women with breast cancer, unmet supportive care needs in this study were significantly lower than previously reported, although assistance with energy levels (i.e. fatigue) continues to be an unmet need for women with breast cancer. Results suggest there have been positive cultural changes within healthcare systems, specifically in better informing patients and providing support. Although services appear to be more responsive to breast cancer patients, significant unmet needs still exist. Copyright © 2007 John Wiley & Sons, Ltd.
Vascular endothelial growth factor and psychosocial factors in colorectal cancer
Authors: Sharma A. , Greenman J. , Sharp D. M. , Walker L. G. , Monson J. R. T. 
Published: April 2007

AbstractBackground: Vascular endothelial growth factor (VEGF) and psychosocial factors have both been shown to have independent prognostic value in colorectal cancer. Recently, an association between VEGF and psychosocial factors has been reported in patients with ovarian cancer.Methods: A consecutive series of eligible patients undergoing elective resection for colorectal cancer were invited to participate. Standardized measures of various aspects of quality of life (QoL) were administered 5–12 days before surgery, and again 6–8 weeks after the operation, blood samples were obtained at the same times. Solid phase ELISA was used for VEGF‐A analysis using serum samples. Correlations and multiple regression analysis were used to examine the relationship between VEGF and psychosocial factors.Results: One hundred and four patients with colorectal cancer were recruited. Seventy (67%) were male and the mean age was 67.6 years.A significant positive correlation was found between preoperative VEGF level and preoperative depression (r=0.227, p=0.03). Preoperative VEGF was negatively correlated with preoperative cancer‐related concerns (r=−0.273, p=0.009) and positive affectivity (r=−0.219, p=0.05). Linear regression using TNM stage as a covariate showed that cancer‐related concerns were an independent predictor of preoperative VEGF levels (p=0.02).Preoperative cancer‐related concerns and global QoL were negatively correlated with postoperative VEGF (r=−0.381, p=0.001, r=−0.264, p=0.005), whereas preoperative depression correlated positively with postoperative VEGF (r=0.333, p=0.003). Linear regression analysis showed that preoperative HADS depression (p=0.005) and cancer‐related concerns (p=0.002) were independent predictors of postoperative VEGF levels.Postoperative VEGF was significantly correlated with postoperative anxiety (r=0.249, p=0.02), depression (r=0.289, p=0.01), and functional well‐being (r=−0.242, p=0.03). Linear regression analysis showed that postoperative anxiety (p=0.048), depression (p=0.013) and functional well‐being (p=0.046) independently predicted postoperative VEGF‐A levels.Conclusion: Various psychosocial factors, particularly cancer‐related concerns and depression, appear to be related to preoperative and postoperative VEGF level in patients with newly diagnosed colorectal cancer. However, the clinical significance of these findings needs to be addressed in longitudinal follow‐up studies of recurrence and survival. Future prognostic studies involving VEGF and related cytokines should assess psychosocial variables at various time points and include these in a multivariate analysis of outcomes. Copyright © 2007 John Wiley & Sons, Ltd.
The use and perceived benefit of complementary and alternative medicine among Californians with cancer
Authors: Goldstein Michael S. , Lee Jennifer H. , Ballard‐Barbash Rachel , Brown E. Richard 
Published: April 2007

AbstractPopulation‐based data on complementary and alternative medicine (CAM) use among cancer sufferers is lacking. In a telephone survey representative of California households (response rate = 68.9%, N = 1845) those who reported a diagnosis of cancer (excluding non‐melanoma skin cancers) were asked about CAM use. CAM use is substantial, although with few exceptions, it is approximately that found among those with non‐malignant chronic conditions. Those with cancer are more likely to report praying for their health, using support groups, and taking multiple dietary supplements. They are less apt to use CAM providers or special diets. Socio‐demographic factors associated with CAM use vary by specific CAM modality. Site of the cancer was not associated with any particular CAM modality. The use of CAM therapies specifically promoted as cancer therapies was not common, especially among those diagnosed recently. The use of CAM providers and mind–body techniques specifically for the purpose of treating cancer is unusual (<10%), while special diets are more frequently employed for the purpose of treatment and/or prevention of the cancer itself. A clear majority of those who do use CAM for treating cancer report at least some benefit from the treatment, and are likely to inform their physicians of such use. Copyright © 2007 John Wiley & Sons, Ltd.
Factors associated with breast cancer‐specific distress in younger women participating in a family history mammography screening programme
Authors: Henderson B. J. , Tyndel S. , Brain K. , Clements A. , Bankhead C. , Austoker J. , Watson E. ,   on behalf of the PIMMS Study Management Group
Published: April 2007

AbstractThis multi‐centre study examined factors associated with breast cancer‐specific distress in 2321 women under 50 who are on a mammographic screening programme on account of their family history. Women were recruited from 21 UK centres, and completed a questionnaire one month before their screening appointment. The transactional theory of stress, appraisal, and coping provided the theoretical framework for the study. Factors measured included screening history, family history, perceived risk, cognitive appraisals, coping, optimism, and cancer worry. The findings indicate that the majority of women appraise their family history as being relevant and somewhat threatening to personal well‐being, but something they can deal with emotionally. Acceptance was the most commonly used coping strategy. Hierarchical regression analysis identified that the factors most significantly associated with distress were an appraisal of high relevance and threat, increased risk perception, low dispositional optimism, and the use of both avoidant and task‐orientated coping strategies. Women with children and those with relatives who have died from breast cancer were also more distressed. To conclude, most women appraised their situation positively but there is a potential profile of risk factors which may help clinicians identify those women who need extra psychological support as they progress through screening. Copyright © 2007 John Wiley & Sons, Ltd.
Protein profiling of oral brush biopsies: S100A8 and S100A9 can differentiate between normal, premalignant, and tumor cells
Authors: Driemel Oliver , Murzik Ulrike , Escher Niko , Melle Christian , Bleul Annett , Dahse Regine , Reichert Torsten Eugen , Ernst Günter , von Eggeling Ferdinand 
Published: April 2007

AbstractIn oral mucosa lesions it is frequently difficult to differentiate between precursor lesions and already manifest oral squamous cell carcinoma. Therefore, multiple scalpel biopsies are necessary to detect tumor cells already in early stages and to guarantee an accurate follow‐up. We analyzed oral brush biopsies (n = 49) of normal mucosa, inflammatory and hyperproliferative lesions, and oral squamous cell carcinoma with ProteinChip Arrays (SELDI) as a non‐invasive method to characterize putative tumor cells. Three proteins were found that differentiated between these three stages. These three proteins are able to distinguish between normal cells and tumor cells with a sensitivity of 100% and specificity of 91% and can distinguish inflammatory/hyperproliferative lesions from tumor cells with a sensitivity of up to 91% and specificity of up to 90%. Two of these proteins have been identified by immunodepletion as S100A8 and S100A9 and this identification was confirmed by immunocytochemistry. For the first time, brush biopsies have been successfully used for proteomic biomarker discovery. The identified protein markers are highly specific for the distinction of the three analyzed stages and therewith reflect the progression from normal to premalignant non‐dysplastic and finally to tumor tissue. This knowledge could be used as a first diagnostic step in the monitoring of mucosal lesions.
Formation of 3‐nitrotyrosines in carbonic anhydrase III is a sensitive marker of oxidative stress in skeletal muscle
Authors: Vasilaki Aphrodite , Simpson Deborah , McArdle Francis , McLean Lynne , Beynon Robert J. , Van Remmen Holly , Richardson Arlan G. , McArdle Anne , Faulkner John A , Jackson Malcolm J. 
Published: April 2007

AbstractOxidation of skeletal muscle proteins has been reported to occur following contractions, with ageing, and with a variety of disease states, but the nature of the oxidised proteins has not been identified. A proteomics approach was utilised to identify major proteins that contain carbonyls and/or 3‐nitrotyrosine (3‐NT) groups in the gastrocnemius (GTN) muscles of adult (5–11 months of age) and old (26–28 months of age) wild type (WT) mice and adult mice lacking copper, zinc superoxide dismutase (Sod1−/− mice), manganese superoxide dismutase (Sod2+/− mice) or glutathione peroxidase 1 (GPx1−/− mice). In quiescent GTN muscles of adult and old WT mice, protein carbonylation and/or formation of 3‐NT occurred in several proteins involved in glycolysis, as well as creatine kinase and carbonic anhydrase III. Following contractions, the 3‐NT intensity was increased in specific protein bands from GTN muscles of both adult and old WT mice. In quiescent GTN muscles from adult Sod1−/−, Sod2+/− or GPx1−/− mice compared with age‐matched WT mice only carbonic anhydrase III showed a greater 3‐NT content. We conclude that formation of 3‐NT occurs readily in response to oxidative stress in carbonic anhydrase III and this may provide a sensitive measure of oxidative damage to muscle proteins.
Differences in the proteome profile in placenta from normal term and preeclamptic preterm pregnancies
Authors: Webster Rose P. , Pitzer Brad A. , Roberts Victoria H. J. , Brockman Diane , Myatt Leslie 
Published: April 2007

AbstractThe aim of this study was to use proteomic approaches to examine differences in protein expression in placentae from normal term and preterm preeclamptic pregnancies and to validate the data thus obtained by other independent methods. Using 2‐DE we found that 80% of the proteins were present in both normal and preeclamptic placentae. However, 26 proteins in the normal term placentae were not matched in the preterm preeclamptic group. Six proteins showed increased intensity and one protein was down‐regulated in preeclampsia. Four of the seven proteins that were altered in preeclampsia were further analyzed by Western blot and immunohistochemistry. Identification by MS techniques revealed these proteins to be involved in regulatory pathways activated by stress. This is significant because preeclampsia is a multisystem disorder in human pregnancies that results in considerable oxidative and nitrative stress. Three proteins identified by MS to be Hsp27, catalase, and glucose‐regulated protein were confirmed by Western blot analysis to be significantly up‐regulated in preeclampsia. Endothelial monocyte‐activating polypeptide was shown to be down‐regulated in preeclampsia by 2‐DE and MS.
Proton pathways and H+/Cl− stoichiometry in bacterial chloride transporters
Authors: Kuang Zhifeng , Mahankali Uma , Beck Thomas L. 
Published: April 2007

AbstractH+/Cl− antiport behavior has recently been observed in bacterial chloride channel homologs and eukaryotic CLC‐family proteins. The detailed molecular‐level mechanism driving the stoichiometric exchange is unknown. In the bacterial structure, experiments and modeling studies have identified two acidic residues, E148 and E203, as key sites along the proton pathway. The E148 residue is a major component of the fast gate, and it occupies a site crucial for both H+ and Cl− transport. E203 is located on the intracellular side of the protein; it is vital for H+, but not Cl−, transport. This suggests two independent ion transit pathways for H+ and Cl− on the intracellular side of the transporter. Previously, we utilized a new pore‐searching algorithm, TransPath, to predict Cl− and H+ ion pathways in the bacterial ClC channel homolog, focusing on proton access from the extracellular solution. Here we employ the TransPath method and molecular dynamics simulations to explore H+ pathways linking E148 and E203 in the presence of Cl− ions located at the experimentally observed binding sites in the pore. A conclusion is that Cl− ions are required at both the intracellular (Sint) and central (Scen) binding sites in order to create an electrostatically favorable H+ pathway linking E148 and E203; this electrostatic coupling is likely related to the observed 1H+/2Cl− stoichiometry of the antiporter. In addition, we suggest that a tyrosine residue side chain (Y445), located near the Cl− ion binding site at Scen, is involved in proton transport between E148 and E203. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Short‐period InAs/GaSb superlattices for mid‐infrared photodetectors
Authors: Haugan H. J. , Szmulowicz F. , Brown G. J. , Ullrich B. , Munshi S. R. , Wickett J. C. , Stokes D. W. 
Published: April 2007

AbstractUsing a newly developed envelope function approximation model that includes interface effects, several InAs/GaSb type‐II superlattices (SLs) were designed for uncooled mid‐infrared detector applications. The 4 micron cutoff could be achieved with several SL designs. Superlattices with shorter periods have larger intervalence band separations than larger‐ones, which could increase the optical signal and reduce the detector noise, thus making room temperature operation possible. To test these possibilities, several short‐period SLs were grown by molecular‐beam epitaxy and their optical properties with reducing SL period were studied by band‐edge absorption, photoconductivity and photoluminescence measurements. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ir/Pt Schottky contact oxidation for nitride‐based Schottky barrier diodes
Authors: Chang P. C. , Yu C. L. , Liu C. H. , Chang S. J. , Su Y. K. , Chuang R. W. , Chiu Y. J. 
Published: April 2007

AbstractWe have fabricated Schottky diodes on GaN epitaxial wafer by using Ir/Pt Schottky contacts. After oxidation, the measured leakage current was decreased from 116 nA to 17.8 pA. In other words, the leakage current after annealing in O2 was shown to be about four orders of magnitude smaller than that before annealing. These improvements may be attributed to IrOx formation of the metal layer, improvement of interface between the Schottky contact and the GaN layer and curing of defects due to oxidation. We also found that the Schottky barrier height and thermal stability after annealing is better than without annealing. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
High responsivity ultraviolet photodetector based on crack‐free GaN on Si (111)
Authors: Wang Xiaoyan , Wang Xiaoliang , Wang Baozhu , Xiao Hongling , Liu Hongxin , Wang Junxi , Zeng Yiping , Li Jinmin 
Published: April 2007

AbstractA Schottky‐based metal‐semiconductor‐metal photodetector is fabricated on 1µm‐thick, crack‐free GaN on Si (111) substrate using an optimized AlxGa1–xN/AlN complex buffer layer. It exhibits a high responsivity of 4600A/W at 366nm which may be due to both a crack‐free sample and high internal gain. The relationship between responsivity and bias voltage is also investigated. The experiment results indicate that the responsivity increases with the bias voltage and shows a tendency to saturate. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)