bluuebunny/crossref_metadata_2025_split huggingface dataset:
T2 exchange agents: A new class of paramagnetic MRI contrast agent that shortens water T2 by chemical exchange rather than relaxation
Authors: Soesbe Todd C. , Merritt Matthew E. , Green Kayla N. , Rojas‐Quijano Federico A. , Sherry A. Dean 
Published: May 2011

AbstractExchange of water molecules between the frequency‐shifted inner‐sphere of a paramagnetic lanthanide ion and aqueous solvent can shorten the T2 of bulk water protons. The magnitude of the line‐broadening T2 exchange (T2exch) is determined by the lanthanide concentration, the chemical shift of the exchanging water molecule, and the rate of water exchange between the two pools. A large T2exch contribution to the water linewidth was initially observed in experiments involving Eu3+‐based paramagnetic chemical exchange saturation transfer agents in vivo at 9.4 T. Further in vitro and in vivo experiments using six different Eu3+ complexes having water exchange rates ranging from zero (no exchange) to 5 × 106 s−1 (fast exchange) were performed. The results showed that the exchange relaxivity (r2exch) is small for complexes having either very fast or very slow exchange, but reaches a well‐defined maximum for complexes with intermediate water exchange rates. These experimental results were verified by Bloch simulations for two site exchange. This new class of T2exch agent could prove useful in the design of responsive MRI contrast agents for molecular imaging of biological processes. Magn Reson Med, 2011. © 2011 Wiley Periodicals, Inc.
Normal bladder sensations in healthy volunteers: A focus group investigation
Authors: Heeringa Rhea , de Wachter Stefan G.G. , van Kerrebroeck Philip E.V. , van Koeveringe Gommert A. 
Published: May 2011

AbstractAimsTo describe the bladder sensations experienced during non‐invasive rapid bladder filling in a controlled setting in healthy volunteers.MethodsThree groups of healthy volunteers, total 11 subjects (4 men, 7 women), participated in three consecutive focus group sessions. Before each session a strict water loading protocol was given. The first two sessions focused on how participants described and experienced bladder sensations in daily life and during a physiological bladder filling with constant focus on their bladder. The third session focused on verifying the interpretation of the data gathered so far and describing the pattern of sensations.ResultsDuring the focus group sessions with constant focus on their bladder, all participants experienced their bladder sensation as a continuous progression. Healthy subjects describe their bladder sensation(s) as a “pressure” and a “tingling” sensation, but a terminology ranging from no sensations to an absolute need to void is used by all participants and better describes the pattern in which the need to void develops in healthy volunteers.ConclusionsBy means of focus group research it is possible to describe the development of normal bladder sensation and to refine terminology used by healthy participants. The findings show that two types of bladder sensations are reported spontaneously by healthy uninitiated volunteers, pressure and a tingling sensation, of which the first develops in a continuous manner. The pattern in which the absolute need develops is described by the terms: no sensation, weak awareness, stronger awareness, weak need, stronger need and absolute need to void. Neurourol. Urodynam. 30:1350–1355, 2011. © 2011 Wiley‐Liss, Inc.
Evaluation of demographic, clinical characteristics, and genetic polymorphism as risk factors for pelvic organ prolapse in brazilian women
Authors: Martins Karina de Falco , Bella Zsuzsanna Ilona Katalin de Jármy‐Di , da Fonseca Andrea Moura Rodrigues Maciel , Castro Rodrigo Aquino , Guerreiro da Silva Ismael Dale Cotrim , Castello Girão Manoel João Batista , Ferreira Sartori Marair Gracio 
Published: May 2011

AbstractObjectiveVerify the association between genital prolapse, other risk factors and a polymorphism in exon 31 of the collagen III‐a1 gene (COL3A1).SettingThe etiology of genital prolapse is multifactorial, and genetic defects have been proposed. Also, there is evidence that changes in collagen may be responsible for defects in pelvic floor support. The exon 31 polymorphism results in structural changes in the triple helical of the collagen and appears to lead to abnormal synthesis of type III collagen.DesignBasic science study.PopulationThe studied group consisted of 107 patients with stage III and IV genital prolapse (POP‐Q). The control group included 209 women with stage 0 and I prolapse.MethodsAfter extracting genomic DNA from the peripheral blood, the exon 31 COL3A1 polymorphism was typed by restriction fragment length polymorphism analysis.Main outcome measuresAssociation between genital prolapse and exon 31 COL3A1 polymorphism.ResultsNo statistically significant differences in genotype and allele frequencies were found between cases and controls (P = 0.75 and 0.66, respectively). Multiple logistic regression analyses identified age (OR = 1.05; 95%CI = 1.01–1.10), BMI (OR = 1.09; 95%CI = 1.01–1.17), presence of at least one vaginal delivery (OR = 7.22; 95%CI = 1.84–28.27), positive family history of POP (OR = 2.27; 95%CI = 1.05–4.93) and a macrosomic foetus (OR = 2.91; 95%CI = 1.24–6.79) as independent risk factors for genital prolapse. In contrast, the number of caesarean deliveries was found to be an independent protective factor (OR = 0.43; 95%CI = 0.24–0.78).ConclusionsThe type III collagen exon 31 polymorphism is not a risk factor for pelvic genital prolapse in this sample. Neurourol. Urodynam. 30:1325–1328, 2011. © 2011 Wiley‐Liss, Inc.
Development and validation of a diabetes knowledge questionnaire
Authors: Eigenmann CA , Skinner T , Colagiuri R 
Published: May 2011

AbstractAn Australian National Consensus Position on Outcomes and Indicators for Diabetes Education identified knowledge and understanding as the outcomes most directly affected by diabetes education. A subsequent literature review failed to identify a validated, suitable questionnaire for measuring knowledge. Consequently, we aimed to develop a minimum diabetes knowledge questionnaire (DKQ) suitable for people with both type 1 and type 2 diabetes.Content validity was established through literature review, Delphi survey of 52 opinion leaders and a workshop of Australian Diabetes Educators (n ≥300). The resulting instrument was tested for internal consistency on 129 and for reliability on 57 people with type 1 and type 2 diabetes, respectively.The final questionnaire contains: 12 multiple choice questions common to type 1 and type 2 diabetes, e.g. normal blood glucose levels, complications, diet, exercise, self‐monitoring of blood glucose, annual check‐ups, support services, and sick‐days; two questions for people on oral medication/insulin only; and one question (sick‐days) for people with type 1 diabetes only.For the first 12 questions, the internal consistency was good (Cronbach's α=0.73); with the additional item for type 1 diabetes, the internal consistency was slightly better (α=0.79) as it was with the additional items for people on medication/insulin (α=0.76). No particular item seemed to adversely affect the overall consistency of the questionnaire.Comparing test‐retest pilots, total scores showed good reliability with no evidence of change over time (t=1.73; df=56; p<0.85), and a correlation of 0.62.The DKQ is now ready to use for evaluating knowledge outcomes of diabetes education. Copyright © 2011 John Wiley & Sons.
Could glucose self‐monitoring become the preferred tool for screening and monitoring glucose control in cystic fibrosis?
Authors: McLachlan CYL , Beach R , Laing R , Frazer G , Lunt H , Cawood TJ 
Published: May 2011

AbstractWe aimed to assess the utility and acceptability of outpatient glucose self‐monitoring in an adult cystic fibrosis (CF) population.Adults with CF were asked to self‐monitor their capillary glucose, three times per day for two weeks preceding their hospital outpatient appointment. The American Diabetes Association definition of dysglycaemia was used, defined by at least two elevated glucose recordings of fasting glucose ≥5.6mmol/L or post‐prandial glucose ≥7.8mmol/L.From a CF population of 43 patients, 10 were excluded (mainly due to clinic in‐attendance). Of the remaining 33 patients, 29 (88%) consented to perform glucose self‐monitoring, and 22 patients (67% of eligible patients and 76% of those consenting to take part) provided glucose data. Dysglycaemia was found in 19 of 22 patients (86%).We conclude that glucose self‐monitoring in the weeks prior to outpatient CF clinic review could become the preferred tool for screening and monitoring of dysglycaemia in adult CF. Copyright © 2011 John Wiley & Sons.
Insulin therapy in patients with cystic fibrosis related diabetes mellitus: benefit, timing of initiation and hypoglycaemia
Authors: Drummond RS , Ross E , Bicknell S , Small M , Jones GC 
Published: May 2011

AbstractPancreatic endocrine dysfunction in patients with cystic fibrosis heralds declining pulmonary function and a six‐fold rise in mortality. Insulin therapy increases weight and reduces decline in lung function. Optimal timing of initiation remains contentious but early intervention may maximise benefit. We explored the optimal timing of initiation of therapy and characterised the frequency and usual symptoms of hypoglycaemia.Fifty‐four patients with cystic fibrosis treated with insulin were compared up to five years pre and post insulin initiation with respect to weight gain and lung function. Frequency and usual symptoms of hypoglycaemia were assessed using the Hypoglycemia Symptoms Awareness Questionnaire.Mean age was 27.6(16–52) years. In the five years preceding insulin therapy, FEV1 declined from 2.6±0.14L to 1.78±0.12L (p<0.001). In the group as a whole, rate of decline was arrested with insulin initiation; the mean five‐year post insulin FEV1 was 1.74±0.20L (p=0.15). When stratified according to oral glucose tolerance testing at initiation the rate of decline was significant in patients with impaired glucose tolerance (p=0.02) but not normal glucose tolerance nor overt cystic fibrosis diabetes mellitus. Insulin therapy increased weight from 53.08±1.53kg to 56.22±2.08kg (p=0.05). Hypoglycaemia was common and 75% of respondents scored results indicative of hypoglycaemia unawareness.This study confirms that the favourable effect of insulin upon lung function in patients with cystic fibrosis correlates with the degree of glucose intolerance at baseline. Hypoglycaemia is an important clinical issue. Copyright © 2011 John Wiley & Sons.
Obstructive sleep apnoea and type 2 diabetes: whose disease is it anyway?
Authors: Choudhury S , Taheri S 
Published: May 2011

AbstractThe association between type 2 diabetes mellitus (T2DM) and obstructive sleep apnoea (OSA) is increasingly recognised. Both conditions are rising in prevalence due to the increased prevalence in obesity, which plays a key role in both disorders. Emerging evidence suggests that T2DM and OSA may also be related independently of obesity. This raises the possibility that identifying and treating OSA in patients with diabetes could have an important impact on diabetes control and cardiovascular health. This article is a summary of the implications of OSA for patients with T2DM. Copyright © 2011 John Wiley & Sons.
Ternary polymer blends of polyamide 6, polypropylene, and acrylonitrile‐butadiene‐styrene: Influence of multiwalled carbon nanotubes on phase morphology, electrical conductivity, and crystallization
Authors: Panda Biswajit , Bhattacharyya Arup R. , Kulkarni Ajit R. 
Published: May 2011

AbstractTernary polymer blends of 80/10/10 (wt/wt/wt) polyamide6 (PA6)/polypropylene (PP)/acrylonitrile‐butadiene‐styrene (ABS), PP/PA6/ABS, and ABS/PP/PA6 were prepared in the presence of multiwalled carbon nanotubes (MWCNTs) by melt‐mixing technique to investigate the influence of MWCNTs on the phase morphology, electrical conductivity, and the crystallization behavior of the PP and PA6 phases in the respective blends. Morphological analysis showed the “core–shell”‐type morphology in 80/10/10 PA6/PP/ABS and 80/10/10 PP/PA6/ABS blends, which was found to be unaltered in the presence of MWCNTs. However, MWCNTs exhibited “compatibilization‐like” action, which was manifested in a reduction of average droplet size of the dispersed phase/s. In contrast, a separately dispersed morphology has been found in the case of 80/10/10 ABS/PP/PA6 blends in which both the phases (PP and PA6) were dispersed separately in the ABS matrix. The electrical percolation threshold for 80/10/10 PA6/PP/ABS and 80/10/10 PP/PA6/ABS ternary polymer blends was found between 3–4 and 2–3 wt% of MWCNTs, respectively, whereas 80/10/10 ABS/PP/PA6 blends showed electrically insulating behavior even at 5 wt% of MWCNTs. Nonisothermal crystallization studies could detect the presence of MWCNTs in the PA6 and the PP phases. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Polyurea microcapsules: Surface modification and capsule size control
Authors: Li Jian , Mazumder M. A. Jafar , Stöver Harald D. H. , Hitchcock Adam P. , Shirley Ian M. 
Published: May 2011

AbstractA postmodification method for polyurea microcapsule (PUMC) surfaces using functional polyelectrolytes is reported in this article. Fluorescein isothiocyanate (FITC) was used to probe the chemistry on PUMC surface and label nucleophilic groups on the surface, in particular amines. As well, a fluorescently labeled polyanion containing electrophilic acetoacetate groups was used to covalently react with these nucleophilic groups on the PUMC surfaces. This modification causes charge reversion of the originally cationic PUMC and enables subsequent layer‐by‐layer (LbL) coating using other polyelectrolytes, allowing for covalent or noncovalent modification of the capsule surface. All modification steps were monitored using either laser scanning confocal microscopy or fluorescence microscopy. Optical and fluorescence microscopy of PUMC wall cross‐sections embedded in resin confirmed that the modifications were restricted to the outer surface of PUMCs, offering minimum interference of this modification method with other capsule wall properties. In addition, a simple T‐junction type microfluidic device based on a commercially available MicroTEE was designed to produce narrowdisperse PUMCs. This device was easy to set up and operate and was proved to be an useful tool for making monodisperse emulsions and narrowdisperse MCs. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Thermoreversible gelation of helical polypeptide/single‐walled carbon nanotubes and their solid‐state structures
Authors: Tang Haoyu , Lee Chang‐Uk , Zhang Donghui 
Published: May 2011

AbstractSingle‐walled carbon nanotubes (SWCNTs) have been functionalized with poly(γ‐benzyl‐L‐glutamate)s (PBLGs) having well‐defined polymer molecular weight (Mn = 7.5–21.1 kg·mol−1) and molecular weight distribution (PDI = 1.05–1.20) by a graft‐to method. Toluene solutions containing 5 wt % free PBLG and variable amounts of PBLG‐functionalized SWCNTs (PBLG‐SWCNTs) form gels at room temperature. Differential scanning calorimetry (DSC) analysis reveals that the gelation occurs thermoreversibly, in accord with previous studies on the pristine PBLG/toluene gels. The heat of gel melting (ΔHm) is slightly elevated for the composite gels compared with the pristine gel, which suggests enhanced interactions between PBLGs in the former. But the gelation temperatures of the composites are unaffected by the presence of PBLG‐SWCNTs. Small‐angle X‐ray scattering (SAXS) analysis of the composite and pristine gels at different temperatures by the Guinier method suggests that PBLG‐SWCNTs promote interactions between PBLG rods, as indicated by the larger PBLG bundle size with increasing PBLG‐SWCNT content in the gel and the melt state. W/SAXS analysis of the dry gels reveals that PBLG‐SWCNTs induce significant changes in the PBLG packing order, resulting in a nematic phase, in contrast to a weakly ordered smectic C phase containing tilted PBLG rods that is observed in the pristine gel. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Synthesis and characterization of poly(ethylene glycol) diacrylate copolymers containing azobenzene groups prepared by frontal polymerization
Authors: Illescas Javier , Ramirez‐Fuentes Yessica S. , Rivera Ernesto , Morales‐Saavedra Omar G. , Rodríguez‐Rosales Antonio A. , Alzari Valeria , Nuvoli Daniele , Scognamillo Sergio , Mariani Alberto 
Published: May 2011

AbstractA novel polymer matrix containing amino–nitro substituted azobenzene groups was obtained by frontal polymerization. (E)‐2‐(Ethyl(4‐((4‐nitrophenyl)diazenyl)phenyl)amino)ethyl methacrylate (MDR‐1) was copolymerized with poly(ethylene glycol) diacrylate (PEGDA) using this easy and fast polymerization technique. The effect of the amount of the incorporated azo‐monomer into the polymer matrix was studied in detail and correlated to front velocity, maximum temperature, initiator concentration, and monomer conversion. The obtained materials were characterized by infrared spectroscopy (Fourier transform infrared), and their thermal properties were studied by thermogravimetric analysis and differential scanning calorimetry. Moreover, the optical properties of the polymers were studied by absorption spectroscopy in the UV–Vis region. Absorption spectra of the copolymers exhibit a significant blue shift of the absorption bands with respect to the azo‐monomer, due to the presence of H‐aggregates. Cubic nonlinear optical (NLO) characterizations of the PEGDA/MDR‐1 copolymers were performed according to the Z‐Scan technique. It has been proven that samples with higher MDR‐1 content (0.75 mol %) exhibited outstandingly high NLO‐activity with negative NLO‐refractive coefficients in the promising range of n2 = −8.057 × 10−4 esu. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Dibenzophenazine derivatives as visible photosensitizers for diaryliodonium salts
Authors: Bulut Umut , Kolay Merve , Tarkuc Simge , Toppare Levent 
Published: May 2011

AbstractThe use of two dibenzo[a,c]phenazine derivatives, 10,13‐bis(2,3‐dihydrothieno[3,4‐b][1,4]dioxin‐5‐yl)dibenzo[a,c]phenazine and 10,13‐bis(4‐hexylthiophen‐2‐yl)dibenzo[a,c]phenazine are reported as photosensitizers for diaryliodonium salt photoinitiators. Novel dyes based on the dibenzo[a,c]phenazine skeleton are shown to be efficient in carrying out the cationic photopolymerizations. Representative examples of different types of monomers including epoxide, and vinyl monomers are polymerized in the presence of the photosensitizers and diphenyliodonium hexafluorophosphate (Ph2I+PF). Polymerizations are initiated at room temperature using long wavelength UV and visible light, and monitored by optical pyrometry. The photopolymerization of an epoxide monomer via solar irradiation is also demonstrated. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011
Why is understanding glassy polymer mechanics so difficult?
Authors: Hoy Robert S. 
Published: May 2011

AbstractIn this Perspective, I describe recent work on systems in which the traditional distinctions between (i) unentangled versus well‐entangled systems and (ii) melts versus glasses seem least useful, and argue for the broader use in glassy polymer mechanics of two more dichotomies: systems which possess (iii) unary versus binary and (iv) cooperative versus noncooperative relaxation dynamics. I discuss the applicability of (iii–iv) to understanding the functional form of strain hardening. Results from molecular dynamics simulations show that the “dramatic” hardening observed in densely entangled systems is associated with a crossover from unary, noncooperative to binary, cooperative relaxation as strain increases; chains stretch between entanglement points, altering the character of local plasticity. Promising approaches for future research along these lines are discussed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011
Nuclear magnetic resonance structure of calcium‐binding protein 1 in a Ca2+‐bound closed state: Implications for target recognition
Authors: Park Saebomi , Li Congmin , Ames James B. 
Published: May 2011

AbstractCalcium‐binding protein 1 (CaBP1), a neuron‐specific member of the calmodulin (CaM) superfamily, regulates the Ca2+‐dependent activity of inositol 1,4,5‐triphosphate receptors (InsP3Rs) and various voltage‐gated Ca2+ channels. Here, we present the NMR structure of full‐length CaBP1 with Ca2+ bound at the first, third, and fourth EF‐hands. A total of 1250 nuclear Overhauser effect distance measurements and 70 residual dipolar coupling restraints define the overall main chain structure with a root‐mean‐squared deviation of 0.54 Å (N‐domain) and 0.48 Å (C‐domain). The first 18 residues from the N‐terminus in CaBP1 (located upstream of the first EF‐hand) are structurally disordered and solvent exposed. The Ca2+‐saturated CaBP1 structure contains two independent domains separated by a flexible central linker similar to that in calmodulin and troponin C. The N‐domain structure of CaBP1 contains two EF‐hands (EF1 and EF2), both in a closed conformation [interhelical angles = 129° (EF1) and 142° (EF2)]. The C‐domain contains EF3 and EF4 in the familiar Ca2+‐bound open conformation [interhelical angles = 105° (EF3) and 91° (EF4)]. Surprisingly, the N‐domain adopts the same closed conformation in the presence or absence of Ca2+ bound at EF1. The Ca2+‐bound closed conformation of EF1 is reminiscent of Ca2+‐bound EF‐hands in a closed conformation found in cardiac troponin C and calpain. We propose that the Ca2+‐bound closed conformation of EF1 in CaBP1 might undergo an induced‐fit opening only in the presence of a specific target protein, and thus may help explain the highly specialized target binding by CaBP1.
Optical absorption and spectroscopic properties of thulium doped (TeO2)(Nb2O5)(TiO2) glasses
Authors: Kabalci Idris , Tay Turgay , Özen Gönül 
Published: May 2011

AbstractA type of thulium doped tellurite based optical glasses was prepared through conventional melt quenching technique. In the experiments, the effect of different Tm3+ ion concentration and glass composition on optical properties of (TeO2)(1‐x‐y)(Nb2O5)(x)(TiO2)(y) (x=0.05, 0.10, 0.15, and 0.20 mol) glasses have been investigated by using UV‐VIS‐NIR optical spectrophotometry measurements in a wavelength range 400‐2000 nm. Considering absorption measurements for the 1.0mol% Tm3+ doped of (TeO2)0.9(Nb2O5)0.05(TiO2)0.05 glass, 1G4, 3F2, 3F3, 3F4, 3H5, and 3H4 absorption bands were observed from the 3H6 ground level, at 463, 660, 687, 793, 1211 and 1700 nm wavelengths, respectively. Furthermore, spontaneous emission probabilities, and the radiative lifetimes for the 4f‐4f transitions of the Tm3+ ions were calculated. The spectral intensities were determined in terms of Judd‐Ofelt parameters (Ω2, Ω4, Ω6). Luminescence analysis was realized for the different Tm3+ ion concentration (0.002, 0.005 and 0.01mol) at room temperature. The luminescence band intensity of the 3F4→3H4 transition was measured as a function of Tm3+ ion concentration (0.002, 0.005 and 0.01mol). Furthermore, luminescence data of the thulium doped glass samples were used to determine the compositional dependence of the emission cross sections at 1470 nm (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)