bluuebunny/crossref_metadata_2025 huggingface dataset:
Motivational Interviewing Improves Weight Loss in Women With Type 2 Diabetes
Authors: West Delia Smith , DiLillo Vicki , Bursac Zoran , Gore Stacy A. , Greene Paul G.
Published: April 2007

OBJECTIVE—We sought to determine whether adding motivational interviewing to a behavioral weight control program improves weight loss outcomes and glycemic control for overweight women with type 2 diabetes.

RESEARCH DESIGN AND METHODS—We conducted a randomized, controlled, clinical trial in which participants all received an 18-month, group-based behavioral obesity treatment and were randomized to individual sessions of motivational interviewing or attention control (total of five sessions) as an adjunct to the weight control program. Overweight women with type 2 diabetes treated by oral medications who could walk for exercise were eligible. Primary outcomes were weight and A1C, assessed at 0, 6, 12, and 18 months.

RESULTS—A total of 217 overweight women (38% African American) were randomized (93% retention rate). Women in motivational interviewing lost significantly more weight at 6 months (P = 0.01) and 18 months (P = 0.04). Increased weight losses with motivational interviewing were mediated by enhanced adherence to the behavioral weight control program. African-American women lost less weight than white women overall and appeared to have a diminished benefit from the addition of motivational interviewing. Significantly greater A1C reductions were observed in those undergoing motivational interviewing at 6 months (P = 0.02) but not at 18 months.

CONCLUSIONS—Motivational interviewing can be a beneficial adjunct to behavioral obesity treatment for women with type 2 diabetes, although the benefits may not be sustained among African-American women.
Global and Regional Effects of Type 2 Diabetes on Brain Tissue Volumes and Cerebral Vasoreactivity
Authors: Last David , Alsop David C. , Abduljalil Amir M. , Marquis Robert P. , de Bazelaire Cedric , Hu Kun , Cavallerano Jerry , Novak Vera
Published: April 2007

OBJECTIVE—The aim of this study was to evaluate the regional effects of type 2 diabetes and associated conditions on cerebral tissue volumes and cerebral blood flow (CBF) regulation.

RESEARCH DESIGN AND METHODS—CBF was examined in 26 diabetic (aged 61.6 ± 6.6 years) and 25 control (aged 60.4 ± 8.6 years) subjects using continuous arterial spin labeling (CASL) imaging during baseline, hyperventilation, and CO2 rebreathing. Regional gray and white matter, cerebrospinal fluid (CSF), and white matter hyperintensity (WMH) volumes were measured on a T1-weighted inversion recovery fast-gradient echo and a fluid attenuation inversion recovery magnetic resonance imaging at 3 Tesla.

RESULTS—The diabetic group had smaller global white (P = 0.006) and gray (P = 0.001) matter and larger CSF (36.3%, P < 0.0001) volumes than the control group. Regional differences were observed for white matter (−13.1%, P = 0.0008) and CSF (36.3%, P < 0.0001) in the frontal region, for CSF (20.9%, P = 0.0002) in the temporal region, and for gray matter (−3.0%, P = 0.04) and CSF (17.6%, P = 0.01) in the parieto-occipital region. Baseline regional CBF (P = 0.006) and CO2 reactivity (P = 0.005) were reduced in the diabetic group. Hypoperfusion in the frontal region was associated with gray matter atrophy (P < 0.0001). Higher A1C was associated with lower CBF (P < 0.0001) and greater CSF (P = 0.002) within the temporal region.

CONCLUSIONS—Type 2 diabetes is associated with cortical and subcortical atrophy involving several brain regions and with diminished regional cerebral perfusion and vasoreactivity. Uncontrolled diabetes may further contribute to hypoperfusion and atrophy. Diabetic metabolic disturbance and blood flow dysregulation that affects preferentially frontal and temporal regions may have implications for cognition and balance in elderly subjects with diabetes.
Sleep Duration and Snoring in Relation to Biomarkers of Cardiovascular Disease Risk Among Women With Type 2 Diabetes
Authors: Williams Catherine J. , Hu Frank B. , Patel Sanjay R. , Mantzoros Christos S.
Published: April 2007

OBJECTIVE—Sleep habits have been associated with risk of cardiovascular disease (CVD) and metabolic disturbances, but the mechanisms underlying these associations have yet to be fully elucidated. We aim to determine whether sleep duration and/or snoring are associated with biomarkers of CVD in women with type 2 diabetes.

RESEARCH DESIGN AND METHODS—We studied 935 women aged 43–69 years enrolled in the Nurses’ Health Study cohort with type 2 diabetes who had no history of documented coronary heart disease or stroke in 1990. Information on sleep duration and snoring frequency was collected in 1986 from mailed questionnaires, and biomarkers of CVD were measured from blood samples taken in 1989–1990.

RESULTS—Longer sleep duration was associated with increased levels of C-reactive protein after adjusting for age, BMI, lifestyle factors, family history of diabetes, glycemic control, and medication use (P = 0.05). HDL was decreased with short and long sleep duration among normotensive (P = 0.02) but not hypertensive women. More frequent snoring was directly associated with triglycerides (P = 0.02) and inversely associated with HDL cholesterol (0.03) and adiponectin (P = 0.03) in multivariate-adjusted analyses.

CONCLUSIONS—The associations of sleep duration and snoring with lipid profile, hormone measures, and/or inflammatory markers may partially explain the previously reported relationship between sleep habits and cardiovascular and metabolic disorders.
Endothelial Function Varies According to Insulin Resistance Disease Type
Authors: Beckman Joshua A. , Goldfine Allison B. , Dunaif Andrea , Gerhard-Herman Marie , Creager Mark A.
Published: April 2007

OBJECTIVE—We examined the relationship between insulin resistance and vascular function in three insulin-resistant states (type 2 diabetes, non-HIV lipodystrophic diabetes, and nondiabetic polycystic ovary syndrome [PCOS]) and in healthy control subjects.

RESEARCH DESIGN AND METHODS—The population included 12 women with type 2 diabetes, 6 with lipodystrophic diabetes, 10 with PCOS, and 19 healthy female subjects. Metabolic measures included insulin sensitivity by the homeostasis model assessment, lipids, free fatty acids, and adiponectin. High-resolution B-mode ultrasound was used to determine endothelium-dependent and -independent vasodilation.

RESULTS—Type 2 diabetic, liposdystrophic, and PCOS subjects were insulin resistant compared with control subjects (P = 0.001). Flow-mediated vasodilation was reduced in diabetic (3.4 ± 1.3%) compared with control (7.3 ± 1.1%) subjects but not in lipodystrophic (7.7 ± 1.2%) or PCOS (9.9 ± 0.7%) subjects (P = 0.005). Nitroglycerin-mediated vasodilation was attenuated in both diabetic (15.2 ± 2.0%) and lipodystrophic (16.7 ± 3.6%) subjects compared with healthy control (24.6 ± 2.4%) and PCOS (23.2 ± 1.8%) subjects (P = 0.019). Insulin resistance, free fatty acids, adiponectin, or C-reactive protein did not associate with vascular dysfunction.

CONCLUSIONS—Among these different types of patients with insulin resistance, we found abnormal endothelium-dependent vasodilation only in the patients with type 2 diabetes. We postulate that variations in the mechanism of insulin resistance may affect endothelial function differently than glucose homeostasis.
Serum Alanine Aminotransferase Levels Decrease Further With Carbohydrate Than Fat Restriction in Insulin-Resistant Adults
Authors: Ryan Marno Celeste , Abbasi Fahim , Lamendola Cindy , Carter Susan , McLaughlin Tracey Lynn
Published: April 2007

OBJECTIVE—Although weight loss interventions have been shown to reduce steatosis in nonalcoholic fatty liver disease (NAFLD), the impact of dietary macronutrient composition is unknown. We assessed the effect on serum alanine aminotransferase (ALT) concentrations of two hypocaloric diets varying in amounts of carbohydrate and fat in obese insulin-resistant individuals, a population at high risk for NAFLD.

RESEARCH DESIGN AND METHODS—Post hoc analysis of ALT concentrations was performed in 52 obese subjects with normal baseline values and insulin resistance, as quantified by the steady-state plasma glucose (SSPG) test, who were randomized to hypocaloric diets containing either 60% carbohydrate/25% fat or 40% carbohydrate/45% fat (15% protein) for 16 weeks. The primary end point was change in ALT, which was evaluated according to diet, weight loss, SSPG, and daylong insulin concentrations.

RESULTS—Although both diets resulted in significant decreases in weight and SSPG, daylong insulin, and serum ALT concentrations, the 40% carbohydrate diet resulted in greater decreases in SSPG (P < 0.04), circulating insulin (P < 0.01), and ALT (9.5 ± 9.4 vs. 4.2 ± 8.3 units/l; P < 0.04) concentrations. ALT changes correlated with improvement in insulin sensitivity (P = 0.04) and daylong insulin (P < 0.01). Individuals with ALT concentrations above the proposed upper limits experienced significant declines in ALT, unlike those with lower ALT levels.

CONCLUSIONS—In a population at high risk for NAFLD, a hypocaloric diet moderately lower in carbohydrate decreased serum ALT concentrations to a greater degree than a higher-carbohydrate/low-fat diet, despite equal weight loss. This may result from a relatively greater decline in daylong insulin concentrations. Further research with histological end points is needed to further explore this finding.
Efficacy and Cost of Postpartum Screening Strategies for Diabetes Among Women With Histories of Gestational Diabetes Mellitus
Authors: Kim Catherine , Herman William H. , Vijan Sandeep
Published: April 2007

OBJECTIVE—To compare the cost and time to diagnosis associated with several screening strategies for diabetes in women with histories of gestational diabetes mellitus (GDM).

RESEARCH DESIGN AND METHODS—We simulated screening for diabetes with fasting plasma glucose (FPG), a 2-h oral glucose tolerance test (OGTT), and A1C annually, every 2 years, and every 3 years over a period of 12 years. We assumed that women had negative screening tests 6 weeks after delivery, progressed to diabetes at 8% per year, and that each positive FPG and A1C was followed by a confirmatory FPG. For each strategy, we calculated the cost per case detected, cost per woman screened, the percent of cases detected, and the time elapsed with undiagnosed diabetes. In sensitivity analyses, we considered the inclusion of indirect costs, the impact of imperfect adherence to screening strategies, exclusion of confirmatory tests, and lower rates of progression to diabetes.

RESULTS—When annual, biannual, or every 3-year screening strategies were utilized, OGTTs resulted in lower costs per case detected than FPG or A1C. Testing every 3 years resulted in lower costs per case detected compared with more frequent testing. These patterns persisted in sensitivity analyses, except that FPG resulted in lower cost per case detected than OGTT, assuming annual screening and inclusion of indirect costs or assuming annual screening without a confirmatory FPG.

CONCLUSIONS—Screening every 3 years with OGTTs results in the lowest cost per case of detected diabetes.
Insulin Resistance in Liver Cirrhosis Is Not Associated With Circulating Retinol-Binding Protein 4
Authors: Yagmur Eray , Weiskirchen Ralf , Gressner Axel M. , Trautwein Christian , Tacke Frank
Published: April 2007

OBJECTIVE—Retinol-binding protein 4 (RBP4) has been identified as a novel adipokine mediating systemic insulin resistance, and elevated serum RBP4 indicates overt or impending insulin resistance in lean, obese, and type 2 diabetic subjects. As insulin resistance is present in nearly all patients with liver cirrhosis, we evaluated RBP4 in patients with chronic liver disease (CLD).

RESEARCH DESIGN AND METHODS—Serum RBP4 was measured in 111 CLD patients. Ninety-nine age- and sex-matched healthy blood donors served as control subjects. RBP4 gene expression was also quantified in normal and cirrhotic rat liver.

RESULTS—In CLD patients, serum RBP4 was significantly reduced compared with healthy control subjects and closely correlated with the stage of liver cirrhosis. CLD patients without cirrhosis showed normal RBP4 concentrations, which correlated with serum glucose and insulin secretion and inversely correlated with insulin sensitivity. In patients with Child A-C liver cirrhosis, however, RBP4 was not correlated with glucose metabolism or other adipokines, such as adiponectin or resistin, but closely linked to the hepatic biosynthetic capacity, fibrotic changes in liver histology, or clinical complications such as portal hypertension. In an animal model of experimental cirrhosis, hepatic RBP4 gene expression decreased in cirrhotic liver.

CONCLUSIONS—RBP4 appears, unlike in obesity or type 2 diabetes, not to be a relevant systemic factor in the pathogenesis of insulin resistance in liver cirrhosis. Liver function has a tremendous impact on RBP4 levels, and future studies will need to take liver function into account when examining serum RBP4 levels.
Evolutionary mechanisms of circadian clocks
Authors: Rodrigo Guillermo , Carrera Javier , Jaramillo Alfonso
Published: April 2007

An intriguing question in biology is to know how circadian molecular networks could have evolved their particular topologies to adjust to a daily period. We analyze the mechanism of the evolution of such networks by using a computational design strategy that allows for the generation of synthetic networks with a targeted 24 hours oscillation. We have performed a systematic analysis of all possible two-gene network topologies based on a core activator-repressor frequently found in circadian mechanisms. We have considered transcriptional and post-translational regulations to implement this core. We have applied our analysis to both, eukaryotic and prokaryotic circadian machinery. Finally, we conjecture a possible mechanism for the evolution of circadian clocks.
Molecular cloning and analysis of the human PCAN1 (GDEP) promoter
Authors: Liu Wenwen , Chen Weiwen , Zhang Pengju , Yu Chunxiao , Kong Feng , Deng Jingti , Zhang Jianye , Jiang Anli
Published: April 2007

Human PCAN1 (prostate cancer gene 1) is a prostate-specific gene that is highly expressed in prostate epithelial tissue, and frequently mutated in prostate tumors. To better understand the regulation of the PCAN1 gene, a 2.6-kb fragment of its 5′ flanking region was obtained by PCR. Its promoter activity was examined via the dual-luciferase reporter assay after it had been cloned into a pGL3-basic vector generating pGL3-p2.6kb and transfected into LNCaP cells. pGL3-basic and pGL3-control were respectively used as the negative and positive controls. Sequence analysis with the MatInspector database showed that some possible binding sites for the transcriptional factors, NKX3.1, P53, SP1, cEBP and the PPAR/RXR heterodimers may locate on a 2.6-kb region upstream of the PCAN1 gene. To examine the relevant regulation of PCAN1, pGL3-p2.6kb was transfected into the prostate cancer cell line LNCaP, which was treated with R1881 (10−7∼10−9 mol/l), 17β-estradiol (17β-E2, 10−7∼10−9 mol/l), all-trans-retinoic acid (all-trans-RA, 10−5∼10−7 mol/l) or 9-cis-retinoic acid (9-cis-RA, 10−5∼10−7 mol/l), and eukaryotic expression plasmids of NKX3.1, p53, Sp1, Pten, PPARγ or cEBPα were cotransfected with pGL3-p2.6kb into LNCaP cells. pRL-TK, a Renilla luciferase reporter vector, was cotransfected into all the transfection lines as an internal control. The activities of pGL3-p2.6kb (PCAN1 promoter) were analyzed via the dual-luciferase reporter assay 48 h after transfection. The results showed that 9-cis-RA enhanced the PCAN1 promoter activity in a dose-dependent manner, while R1881, 17β-E2 and all-trans-RA had no significant effect on PCAN1 promoter activities. Cotransfection with pGL3-p2.6kb and the expression plasmids of NKX3.1, p53, Sp1 or Pten respectively resulted in 1.66-, 2.48-, 2.00-and 1.72-fold 2.6 kb PCAN1 promoter activity increases relative to the controls, which were cotransfected with pcDNA3.1(+), while cotransfection of PPARγ and cEBPα yielded no significant effect on PCAN1 promoter activities. These results could be applied for further study of the function and transcription regulation of the PCAN1 gene in prostate development and carcinogenesis.
Gyrodactylus derjavinoides sp. nov. (Monogenea, Platyhelminthes) on Salmo trutta trutta L. and G. derjavini Mikailov, 1975 on S. t. caspius Kessler, two different species of Gyrodactylus — combined morphological and molecular investigations
Authors: Malmberg Göran , Collins Catherine , Cunningham Carey , Jalali Behiar
Published: April 2007

The paper deals with two morphologically similar but molecularly clearly different species of Gyrodactylus: G. derjavinoides sp. nov. on Salmo trutta trutta L. in Western Europe and G. derjavini Mikailov. 1975 collected on Salmo trutta caspius Kessler in Iran. The new species is described and its opisthaptoral hard parts compared to those of G. derjavini. Our molecular analysis of G. derjavinoides and G. derjavini confirmed that the morphological differences between them are species differences and not intraspecific variations. Phylogenetic analysis using the ITS rDNA region placed both species within the subgenus G. (Limnonephrotus) and within the G. wageneri-group, quite in accordance with morphological results. The two species, however, did not cluster as sister taxa. The correspondence between molecular-based clades within G. (Limnonephrotus) and the morphological shapes of marginal hooks within these clades are discussed. The importance of combined molecular and morphological analyses when describing or redescribing Gyrodactylus species is stressed.
Monitoring of Biochemical Parameters in Preterm Infants on Special Regime Feeding
Authors: Ljujić-Glišić Miroslava , Božinović-Prekajski Niveska
Published: April 2007

Monitoring of Biochemical Parameters in Preterm Infants on Special Regime Feeding

Enriched human milk may stimulate gain weight in preterm infants during the neonatal period. Aim is the biochemical assessment of preterm infants, fed by mother's milk fortificated with the special domestic formulapreImpamil during the first month of life. 80 preterm infants (45 male and 35 female), up to 36 weeks of gestation, BW less than 2500 g, started enteral intake in the first three days of life. Total volume intake was in range from 70 mL/kg first day, to 170-200 mL/kg after a 10thday of life. Mother's milk fortification was prepared as a 5% mixture solution ofpreImpamil. The dynamics of biochemical analyses started on the first day of study and was repeated once a week. We analysed levels of: total protein, albumin, prealbumin, transferin, urea, Ca ionised, P and alkaline phosphatase using standard biochemical methods. Statistical analyses were completed by ANOVA test, one-factorial analyses of variance. During monitoring the total protein level increased in the second week of life (p<0.01), as well as albumin (p<0.01). Prealbumin level increased, as well as transferin (p-NS). Initial level of ionised fraction of Ca was significantly lower (p<0.01) at the beginning of the study, compared to the rest. Serum level of P increased, as well as the level of alkaline phosphatase at the end of first and second week (p<0.01). Conclusion is that biochemical parameters, such as levels of protein and albumin, are important in the growth assessment of preterm infants on special feeding regimes.
Sozialforschung an der WSL - ein Überblick | Overview of Social Research at the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL)
Authors: Hunziker Marcel , Wallner Astrid
Published: April 2007

The research carried out by the Section of Landscape and Society at the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) deals with the interaction between landscape and society. To date, the following aspects have been studied: (1) the public perception and opinion of developments in nature, landscape and environment, (2) the public perception and opinion of scientific debate on such developments,and (3) social action as a result of these developments. Striving for detailed understanding of these interactions, the methods used were based on techniques of qualitative social research. One research project examined the impact that model experiments on ecosystems had on public environmental discussion. Future research will concentrate on the following aspects of society-landscape-interaction: (1) to what extent the «needs» of the countryside are being met in areas intended for everyday and recreational use, (2) how decisions taken on a global/national level are being implemented at a local/regional, and (3) cultural and regional variations.
Organisation de la recherche dans les zones sèches un cas concret dans l'ouest de Madagascar | Design of Forest Research in Dry Zones -a Case Study in the West of Madagascar
Authors: Sorg Jean-Pierre
Published: April 2007

An interesting research programme focusing on trees and forest,which has been continuing in the region of Morondava for more than 20 years, presently finds itself in an environment somewhat unfavourable for research and, therefore, is in an evaluative phase. While at the beginning the emphasis was strongly put on forestry, the programme developed more and more towards the interface mankind – forest, and through social-forestry activities progressively towards the population of the villages. Today, it is clear that research on participative management of forests and the scientific interest in natural eco-systems and their dynamics are complementary and have to be co-ordinated with regard to sustainability.
Die Hochwasser vom Mai 1999: eine Analyse anhand von hydrologischen Messungen in kleinen Einzugsgebieten | The Flood Events of May 1999: an Analysis Based on Hydrologic Measurements in Small Catchments
Authors: Forster Felix , Hegg Christoph
Published: April 2007

During the melting period of the winter 1998/99, which was rich in snow, large parts of northern Switzerland were covered with two heavy and long-lasting rainfall events resulting in large inundation damage and dangerous flood situations. Although the considered area is rather limited, the extensive hydrologic data set from two small prealpine testcatchments with different basin characteristics offered an excellent opportunity to provide a detailed analysis of the flow processes in May 1999.
Alte Regeln neu interpretiert – Praxisversuche mit termingeschlägertem Holz | Felling Time and Wood Quality
Authors: Teischinger Alfred , Fellner Josef
Published: April 2007

Based on extensive experiments, old wood rules regarding felling time and wood quality are listed and interpreted in a new way. Obsolete rules are eliminated,mistakes handed down are shown and if the rules are useful,the scientific connections are discussed.
Cover Picture: A Route to Self‐Organized Honeycomb Microstructured Polystyrene Films and Their Chemical Characterization by ToF‐SIMS Imaging (Adv. Funct. Mater. 7/2007)
Authors: Yunus S. , Delcorte A. , Poleunis C. , Bertrand P. , Bolognesi A. , Botta C.
Published: April 2007

The cover shows a composition of different characterization images of an auto‐organized polystyrene film obtained through breath‐figure imprinting, as reported by Sami Yunus and co‐workers on p. 1079. Water‐droplet condensation, represented as a synthetic perspective image (top), is responsible for ordered microstructuring during film formation. The following perspectives are taken from SEM and from three negative ToF‐SIMS images that allow deduction of the surface chemical composition. The background is an SEM picture of a polydimethylsiloxane molding of the self‐organized film.

A new type of polymer compound that allows the formation of highly ordered microstructured films by casting from a volatile solvent in the presence of humidity, and its characterization by ToF‐SIMS (time‐of‐flight secondary‐ion mass spectrometry) are presented. A honeycomb structure is obtained by activation of 2,2,6,6‐tetramethyl‐1‐piperidinyloxyl (TEMPO)‐terminated polystyrene (PS) with p‐toluenesulfonic acid (PTSA). The mechanism of this activation reaction, leading to a more polar PS termination, is deduced from simple experiments and supported by ToF‐SIMS characterization. Positive and negative ToF‐SIMS imaging allows different chemical regions correlating to the film morphology to be distinguished. This new, straightforward activation process, together with ToF‐SIMS chemical imaging, provides a better understanding of the phenomena underlying the formation of these films by directly linking the role of polar terminations to the microscale self‐organization. This new method, transposable to other organic acids, suggests interesting new perspectives in the field of self‐organized chemical and topographical patterning.
An iron‐based reverse ATRP process for the living radical polymerization of acrylonitrile
Authors: Hou Chen , Ji Chunnuan , Qu Rongjun , Wang Chunhua , Sun Changmei , Zhou Wenying , Yu Mengmeng
Published: April 2007

A hexa‐substituted ethane thermal iniferter, diethyl‐2,3‐dicyano‐2,3‐di(p‐tolyl) succinate (DCDTS), was firstly used as the initiator in the reverse atom transfer radical polymerization (RATRP) of acrylonitrile. FeCl3 coordinated by isophthalic acid (IA) was used as the catalyst in this system. The polymerization in N,N‐dimethylformamide not only shows the best control of molecular weight and its distribution but also provides rather rapid reaction rate with the ratio of [AN] : [DCDTS] : [FeCl3] : [IA] at 500 : 1 : 2 : 4. The polymers obtained were end‐functionalized by chlorine atom, and they were used as macroinitiators to proceed the chain extension polymerization in the presence of FeCl2/IA catalyst system via a conventional ATRP process and polyacrylonitrile obtained was with Mn = 39,260, PDI = 1.25. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Monte Carlo simulation of the compatibility of graft copolymer compatibilized two incompatible homopolymer blends: Effect of graft structure
Authors: Zhu Yutian , Ma Zengwei , Li Yunqi , Cui Jie , Jiang Wei
Published: April 2007

Compatibility of graft copolymer compatibilized two incompatible homopolymer A and B blends was simulated by using Monte Carlo method in a two‐dimensional lattice model. The copolymers with various graft structures were introduced in order to study the effect of graft structure on the compatibility. Simulation results showed that incorporation of both A‐g‐B (A was backbone) and B‐g‐A (B was backbone) copolymers could much improve the compatibility of the blends. However, A‐g‐B copolymer was more effective to compatibilize the blend if homopolymer A formed dispersed phase. Furthermore, simulation results indicated that A‐g‐B copolymers tended to locate at the interface and anchor two immiscible components when the side chain is relatively long. However, most of A‐g‐B copolymers were likely to be dispersed into the dispersed homopolymer A phase domains if the side chains were relatively short. On the other hand, B‐g‐A copolymers tended to be dispersed into the matrix formed by homopolymer B. Moreover, it was found that more and more B‐g‐A copolymers were likely to form thin layers at the phase interface with decreasing the length of side chain. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis, characterisation, and chemical degradation of segmented polyurethanes with butylamine for chemical recycling
Authors: Elidrissi Abderahmane , Krim Ouassini , Ouslimane Samir , Berrabeh Mohamed , Touzani Rachid
Published: April 2007

Polyurethane elastomers (PU) have been synthesized from polytetramethylene glycol 2000 (PTMG 2000); 4, 4′‐diphenylmethane diisocyanate (MDI) and 1, 4‐butanediol (BD) as chain extender. This synthesis has been done in two steps known as prepolymer methods. The concentration of soft segments and hydrogen attachment in the matrices, have been studied. The results show that the glass transition of the soft segment Tg(s) do not take any changes with the concentration of the soft segment in the matrices. Although, the glass transition temperature of the hard segment Tg(H) increases when the concentration of the hard segment increases in the matrices. In general, the properties of the polyurethane elastomers depend on the extenders nature, the synthesis methods, phase segregation etc. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Preparation and characterization of large porous poly(HEMA‐co‐EDMA) microspheres with narrow size distribution by modified membrane emulsification method
Authors: Qu Huanhuan , Gong Fangling , Ma Guanghui , Su Zhiguo
Published: April 2007

Porous poly(2‐hydroxyethyl methacrylate‐co‐ethylene dimethacrylate) [p(HEMA‐co‐EDMA)] microspheres have important applications in chromatography. In this study, p(HEMA‐co‐EDMA) microspheres with controllable size were successfully prepared by modified membrane emulsification technique. The CV value of the obtained microspheres was as low as 14.4%. An oil phase mainly composed of toluene was permeated through a membrane with uniform pores into an aqueous phase to form fairly uniform seed emulsion. The secondary emulsion composed of HEMA and EDMA was prepared by a homogenizer. Then, the two emulsions were mixed together. HEMA and EDMA diffused into the aqueous phase, and then were absorbed by the seed droplets. The swollen droplets were further polymerized to prepare monodisperse porous microspheres. It was found that HEMA/EDMA ratio and toluene/monomer ratio showed a significant influence on swelling degree, diameter, and morphology of the obtained microspheres. The swelling degree of the microspheres increased with the increase of toluene/monomer ratio, whereas the average diameter increased with decrease of the ratio. Microspheres with controllable size (28–73 μm) and porosity were obtained, by varying HEMA/EDMA ratios and toluene/monomer ratios. It can be expected that the p(HEMA‐co‐EDMA) microspheres with controllable size and porosity will provide many advantages in their applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Mechanism of curing process for polycarbosilane fiber with cyclohexene vapor
Authors: Mao X. H. , Song Y. C. , Li W. , Yang D. X.
Published: April 2007

The reaction process of polycarbosilane (PCS) fiber cured by cyclohexene vapor has been studied and compared with that of PCS fiber cured by air. The influence of curing temperature on SiH bond reaction degree and gel content, the structure and composition of PCS were investigated by FTIR, EA, TGA, NMR, and GC‐MS. The results showed that, SiH bond in the molecular structure of PCS reacted during cyclohexene curing process and the reaction degree increased when the curing temperature increases. Simultaneously, gel content of PCS fiber rapidly increased till PCS fiber became infusible. SiH radical and SiCH2 radicals formed SiCH2Si crosslinking of PCS molecules through the agency of cyclohexene. Some cyclohexyls linked to principal chain of PCS, which was proven by 13C‐CPMAS‐NMR, and broke off, and cyclohexane and some monosilane are generated as byproducts when temperature increased. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Foams based on low density polyethylene/hectorite nanocomposites: Thermal stability and thermo‐mechanical properties
Authors: Velasco J. I. , Antunes M. , Ayyad O. , Saiz‐Arroyo C. , Rodríguez‐Pérez M. A. , Hidalgo F. , de Saja J. A.
Published: April 2007

Novel polymer nanocomposite foams made by a two step compression molding method are analyzed in this article. Nanocomposites of low density polyethylene and an organo‐modified hectorite were first melt compounded and then foamed using a compression molding method. To study the influence of the presence and the amount of hectorite in both mechanical and thermal properties, samples with 3% and 7% content of hectorite were prepared. Polyethylene crystalline characteristics and thermal stability of the samples were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. Mechanical properties of foams and solid nanocomposites were analyzed by using dynamical mechanical analysis (DMA). Thermal expansion of the samples was analyzed by thermomechanical analysis. The results indicate that the exfoliation of hectorite platelets was achieved after the foaming process, but not during the melt mixing step. Foams with hectorite nanoparticles exhibit improved thermal stability and mechanical properties when compared with neat polymeric foams. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Development, optimization, and characterization of electrospun poly(lactic acid) nanofibers containing multi‐walled carbon nanotubes
Authors: McCullen Seth D. , Stano Kelly L. , Stevens Derrick R. , Roberts Wesley A. , Monteiro‐Riviere Nancy A. , Clarke Laura I. , Gorga Russell E.
Published: April 2007

Electrospinning of poly (L‐D‐lactic acid) (PLA) was investigated with the addition of multi‐walled carbon nanotubes (MWNT) for development of a scaffold for tissue engineering. Through this experiment, it was determined that the optimal concentration of PLA with weight average molecular weight (Mw) 250,000 g/mol is ∼20 wt % as indicated by scanning electron microscopy. This concentration produces fibers with no beading or film formation. The preferred solvent system is a combination of chloroform and dimethyl formamide to alleviate the volatile action of chloroform. The optimum processing parameters for PLA are an electric field of 1 kV/cm which was determined by a surface response plot to minimize fiber diameter based on the applied voltage, working distance, and addition of MWNT. Fourier Transform infrared spectroscopy has indicated the removal of the solvent system. With the addition of MWNT, the fiber diameter was drastically reduced by 70% to form fibers with a mean diameter of 700 nm. This is believed to be due to an increased surface charge density for the MWNT/polymer solution. Transmission electron microscopy validated the alignment of the MWNT within the fibers. MWNT loading exhibited an increase in the conductance of the scaffold and the tensile modulus at an optimal loading level of 0.25 wt %. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Supramolecular inclusion complexes of biodegradable cholesteryl‐(ϵ‐caprolactone)n functionalized polymer with α‐cyclodextrin
Authors: Guo Jinbao , Sun Jie , Zhu Siquan , Cao Hui , Zhao Dongyu , Wang Liping , Yang Huai
Published: April 2007

The biodegradable cholesteryl‐(ϵ‐caprolactone)10 (Chol‐(CL)10) functionalized polymer was synthesized and then investigated for inclusion complexation with α‐cyclodextrin (α‐CD). The supramolecular inclusion complexes (ICs) were in detail characterized by fourier transform infrared (FTIR), 1H‐nuclear magnetic resonance, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), wide angle X‐ray diffraction (WAXD), and 13C‐NMR, respectively. All analyses indicated that oligo(ϵ‐caprolactone)10 chains of the Chol‐(CL)10 were included into the hydrophobic α‐CD cavities and their original crystalline properties were completely suppressed. Moreover, the ICs of biodegradable Chol‐(CL)10 functionalized polymer with α‐CD had a channel‐type crystalline structure similar to that formed between the poly(ϵ‐caprolactone) and α‐CD. Further more, The TGA analysis revealed that the ICs had better thermal stability than their free components due to the inclusion complexation, suggesting that the complexation stabilized the polymer included in the CD chan‐nels. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Characterization of metallized biaxially oriented polypropylene film
Authors: Vassiliadi E. , Tarantili P. A.
Published: April 2007

The effect of corona unit energy applied for retreatment of metallized biaxially oriented polypropylene film surfaces before the lamination process was studied using optical, scanning electron, and atomic force microscopies. Increased surface roughness and polarity due to oxygen groups were detected, and these changes became more evident with the increase of corona treatment intensity. The number and size of spots on the surface, possibly deriving from processing aids incorporated as additives into the polymer, increase with corona treatment. The response of specimens in accelerated aging was also studied for evaluation of the outdoor stability of these composite structures. Specimens were exposed to the combined action of UV‐radiation, humidity, and heat, and the stability of yellow, orange‐yellow, orange, green, and bordeaux colors was determined as a function of the exposure time. Minor color changes were recorded for exposure up to 100 h, which became more significant for longer exposure intervals depending on the type of color. Finally, a 40% decrease in tensile strength was observed after 216 h of ageing, accompanied with a decrease of 15% of modulus and an increase of 160% in the elongation at break, possibly because of the plasticizing effect taking place during the ageing process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effect of steady shear on the microstructural evolution of melt‐intercalated polymer/clay nanocomposites
Authors: Wu Defeng , Zhou Chixing , Zhang Ming
Published: April 2007

A sheet sample composed of poly(butylene terephthalate) and clay prepared by solid‐state compression was melt‐annealed in a rheometer under steady shear flow to investigate the whole hybridization process. The results of the offline morphology and thermogravimetric analysis as well as Fourier transform infrared characterization show that shear flow can reduce the dynamic process of hybridization, facilitating the formation of an intercalated nanoscale structure. With an increase in the shear intensity, the detachment level of clay increases more remarkably than the swollen degree. However, an increase in the shear intensity does not induce an exfoliated structure but can decrease the average thickness of the clay tactoids, leading to a remarkable enhancement in the thermal stability due to the increase in the effective filling volume of the clay. Furthermore, those intercalated nanocomposites annealed at a high shear rate still present a distinct hierarchical structure, which suggests that steady shear is not as good as dynamic or complex shear for promoting hybridization effectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Information and higher things in life: Addressing the pleasurable and the profound in information science
Authors: Kari Jarkko , Hartel Jenna
Published: April 2007

The article discusses lower and higher contexts for information phenomena, and argues that there is clearly a need for a more concerted research effort in the latter sphere. The discipline of information science has traditionally favored lower contexts—like everyday life and problem solving—that are neutral or even negative by nature. In contrast, the neglected higher things in life are pleasurable or profound phenomena, experiences, or activities that transcend the daily grind. A literature sample of the scarce information research related to higher things indicates that beyond the spotlight of mainstream research, information processes often seem different and there may be significant dimensions of information phenomena that have been overlooked. Therefore, the article outlines a contextual research area in information studies to address higher things from the perspective of information. It is concluded that optimal functioning requires bringing the lower and higher sides to balance in information science. This would offer a rare chance to promote holism and interdisciplinarity in the field, and to make the discipline more relevant to the human being.
Using lessons from health care to protect the privacy of library users: Guidelines for the de‐identification of library data based on HIPAA
Authors: Nicholson Scott , Smith Catherine Arnott
Published: April 2007

Although libraries have employed policies to protect the data about use of their services, these policies are rarely specific or standardized. Since 1996, the U.S. health care system has been grappling with the Health Insurance Portability and Accountability Act (HIPAA; Health Insurance Portability and Accountability Act, 1996), which is designed to provide those handling personal health information with standardized, definitive instructions as to the protection of data. In this work, the authors briefly discuss the present situation of privacy policies about library use data, outline the HIPAA guidelines to understand parallels between the two, and finally propose methods to create a de‐identified library data warehouse based on HIPAA for the protection of user privacy.
Unexpected Thermally Stable, Cholesteric Liquid‐Crystalline Helical Polyisocyanides with Memory of Macromolecular Helicity
Authors: Hase Yoko , Mitsutsuji Yuuki , Ishikawa Masayoshi , Maeda Katsuhiro , Okoshi Kento , Yashima Eiji
Published: April 2007

The achiral sodium salt of poly(4‐carboxyphenyl isocyanide) (poly‐1–Na) folds into a one‐handed helix induced by optically active amines in water. The induced helicity remains when the optically active amines are completely removed, and further modification of the side groups to amide residues is possible without loss of memory of macromolecular helicity. Although the helical poly‐1–Na loses its chiral memory at high temperature, helical polyisocyanides modified with achiral primary amines, which no longer have any chiral components, keep their memory perfectly even at 100 °C in N,N‐dimethylformamide in some cases and exhibit cholesteric liquid‐crystalline phases, thus providing a robust scaffold with heat resistance to which a variety of functional groups can be introduced.
Modelling financial time series with threshold nonlinearity in returns and trading volume
Authors: So Mike K. P. , Chen Cathy W. S. , Chiang Thomas C. , Lin Doris S. Y.
Published: April 2007

This paper investigates the effect of past returns and trading volumes on the temporal behaviour of international market returns. We propose a class of nonlinear threshold time‐series models with generalized autoregressive conditional heteroscedastic disturbances. Using Bayesian approach, an implementation of Markov chain Monte Carlo procedure is used to obtain estimates of unknown parameters. The proposed family of models incorporates changes in log of volumes in the sense of
regime changes and asymmetric effects on the volatility functions. The results show that when differences of log volumes are involved in the system of log return and volatility models, an optimum selection can be achieved. In all the five markets considered, both mean and variance equations involve volumes in the best models selected. Our best models produce higher posterior‐odds ratios than that in Gerlach et al.'s (Phys. A Statist. Mech. Appl. 2006; 360:422–444) models, indicating that our return–volume partition of regimes can offer extra gain in explaining return‐volatility term structure. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and Characterization of Monodisperse Oligo(fluorene‐co‐bithiophene)s
Authors: Zhang Xiaojie , Qu Yao , Bu Laju , Tian Hongkun , Zhang Jingping , Wang Lixiang , Geng Yanhou , Wang Fosong
Published: April 2007

A series of monodisperse oligo(9,9‐di‐n‐octylfluorene‐co‐bithiophene)s (OFbTs) with molecular lengths of up to 19.5 nm and molecular weights up to 7025 g mol−1 has been synthesized by a divergent/convergent approach involving Stille coupling reactions. Stille coupling is quite efficient in preparing this class of oligomers, and even the molecule with nine fluorene units and eight bithiophene units (F9Th16) can be synthesized in a yield as high as 70 %. Because of easy functionalization of the thiophene ring at its α position, no additional protecting group allowing activation for further reaction is necessary. However, the synthetic routes must be optimized to eliminate contamination of the targeting compounds with the homocoupling product of the organotin reagents. Synthesis of the longest oligomer F13Th24 in a relative large quantity is limited by its low yield due to the pronounced ligand‐exchange side reactions of the starting materials and reaction intermediates. All oligomers longer than F4Th6 are nematic mesomorphs and exhibit enhanced glass transition temperature and clearing point with increasing molecular length, as revealed by differential scanning calorimetry and polarizing optical microscopy. Absorption and photoluminescence (PL) measurements reveal that OFbTs are well‐conjugated systems with an effective conjugation length longer than the length of F13Th24.
Desymmetrisation of a Centrosymmetric Molecule by Carbon–Carbon Bond Formation: Asymmetric Aldol Reactions of a Centrosymmetric Dialdehyde
Authors: Dodd Karen , Morton Daniel , Worden Stephen , Narquizian Robert , Nelson Adam
Published: April 2007

The desymmetrisation of centrosymmetric molecules by enantioselective carbon–carbon bond formation has been reported for the first time. A bimetallic zinc catalyst developed by Trost was exploited in the desymmetrisation of a centrosymmetric dialdehyde. The approach was successful with a range of ketone nucleophiles and was uniformly highly diastereoselective (>98:<2). The yield and the enantioselectivity of the reaction varied as a function of the ketone used, and the desymmetrised products were obtained in up to 74 % yield and 97 % ee (ee=enantiomeric excess). The desymmetrisation of centrosymmetric molecules by enantioselective carbon–carbon bond formation is an efficient and convergent synthetic approach which is likely to find wide application in synthesis, particularly in the total synthesis of natural products with embedded centrosymmetric fragments.
Crystal Structure of the Ln2PbSe4 (Ln: Er and Yb) Compounds.
Authors: Gulay L. D. , Daszkiewicz M. , Stepien‐Damm J. , Pietraszko A.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ln(Au≈0.75Sb≈ 0.25)2 (Ln: La, Ce, Pr) with UHg2 Structure Type, New Members of the AlB2 Family.
Authors: Salamakha L. P. , Sologub O. L. , Goncalves A. P. , Mudryi S. I. , Almeida M.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Crystal Structures of the Ln4In4.72Se13 (Ln: La and Ce) Compounds.
Authors: Gulay L. D. , Huch M. R. , Olekseyuk I. D. , Pietraszko A.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structure and Dielectric Characterization of a New A‐Site Deficient La5/3MgTaO6 Perovskite.
Authors: Khalyavin D. D. , Senos A. M. R. , Mantas P. Q. , Argyriou D. N. , Tarroso Gomes I. , Vieira L. G. , Ribeiro J. L.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Tb2Ni2Mg3: A New Structure Type Derived from the Ru3Al2B2 Type.
Authors: Solokha Pavlo , De Negri Serena , Saccone Adriana , Pavlyuk Volodymyr , Marciniak Bernard , Tedenac Jean‐Claude
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Syntheses, Crystal and Electronic Structure, and Some Optical and Transport Properties of LnCuOTe (Ln: La, Ce, Nd).
Authors: Liu Min Ling , Wu Li Bin , Huang Fu Qiang , Chen Li Dong , Ibers James A.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Properties of the Double Perovskites La2NiVO6, La2CoVO6, and La2CoTiO6.
Authors: Holman K. L. , Huang Q. , Klimczuk T. , Trzebiatowski K. , Bos J. W. G. , Morosan E. , Lynn J. W. , Cava R. J.
Published: April 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.