bluuebunny/crossref_metadata_2025 huggingface dataset:
Reproducibility of same session repeated cystometry and pressure‐flow studies in women with symptoms of urinary incontinence
Authors: Broekhuis Suzan R. , Kluivers Kirsten B. , Hendriks Jan C.M. , Massolt Elske T. , Groen Jan , Vierhout Mark E.
Published: July 2009

Aim

The aim of this study was to determine the reproducibility of same session repeated urodynamic measurements in women with symptoms of urinary incontinence.

Methods

Women presenting with symptoms of urinary incontinence underwent standardized urodynamic examination, which consisted of free uroflowmetry and two filling cystometries and pressure‐flow studies. Intra‐class Correlation Coefficient (ICC) and McNemar tests were used to describe the same session reproducibility.

Results

Two evaluable urodynamic tests were available in 152 patients. Overall, reproducibility of the urodynamic parameters were good to excellent (ICC range: 0.72–0.93), except for the bladder volume at first sensation of bladder filling (ICC = 0.46) and the maximum Watt's factor (ICC = 0.68). The bladder volume at first sensation and the maximum cystometric capacity were systematically higher in the second run (mean difference (95% CI) = −45 (−73; −37) and −3 (−15; 10), respectively). Reproducibility of the diagnosis stress urinary incontinence and/or detrusor overactivity were good to excellent (median ICC = 0.76, P = 0.68 and P = 1.00, respectively). Reproducibility of the volume and amplitude at involuntary detrusor contractions, however, were only poor (ICC = 0.18 and 0.25, respectively).

Conclusions

The reproducibility of same session repeated urodynamic measurements in women with symptoms of urinary incontinence was good to excellent. Our results provide the scientific support for guidelines that recommend the omission of repeated filling cystometries and pressure‐flow studies in cases where the first test confirms the pathology expected. Neurourol. Urodynam. 29:428–431, 2010. © 2009 Wiley‐Liss, Inc.
Concise RLT forms of binary programs: A computational study of the quadratic knapsack problem
Authors: Forrester Richard J. , Adams Warren P. , Hadavas Paul T.
Published: July 2009

The reformulation‐linearization technique (RLT) is a methodology for constructing tight linear programming relaxations of mixed discrete problems. A key construct is the multiplication of “product factors” of the discrete variables with problem constraints to form polynomial restrictions, which are subsequently linearized. For special problem forms, the structure of these linearized constraints tends to suggest that certain classes may be more beneficial than others. We examine the usefulness of subsets of constraints for a family of 0–1 quadratic multidimensional knapsack programs and perform extensive computational tests on a classical special case known as the 0–1 quadratic knapsack problem. We consider RLT forms both with and without these inequalities, and their comparisons with linearizations derived from published methods. Interestingly, the computational results depend in part upon the commercial software used. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2010
Dynamic signatures and their use in comparing the reliability of new and used systems
Authors: Samaniego Francisco J. , Balakrishnan N. , Navarro Jorge
Published: July 2009

The signature of a system with independent and identically distributed (i.i.d.) component lifetimes is a vector whose ith element is the probability that the ith component failure is fatal to the system. System signatures have been found to be quite useful tools in the study and comparison of engineered systems. In this article, the theory of system signatures is extended to versions of signatures applicable in dynamic reliability settings. It is shown that, when a working used system is inspected at time t and it is noted that precisely k failures have occurred, the vector s [0,1]n‐k whose jth element is the probability that the (k + j)th component failure is fatal to the system, for j = 1,2,2026;,n ‐ k, is a distribution‐free measure of the design of the residual system. Next, known representation and preservation theorems for system signatures are generalized to dynamic versions. Two additional applications of dynamic signatures are studied in detail. The well‐known “new better than used” (NBU) property of aging systems is extended to a uniform (UNBU) version, which compares systems when new and when used, conditional on the known number of failures. Sufficient conditions are given for a system to have the UNBU property. The application of dynamic signatures to the engineering practice of “burn‐in” is also treated. Specifically, we consider the comparison of new systems with working used systems burned‐in to a given ordered component failure time. In a reliability economics framework, we illustrate how one might compare a new system to one successfully burned‐in to the kth component failure, and we identify circumstances in which burn‐in is inferior (or is superior) to the fielding of a new system. © 2009 Wiley Periodicals, Inc. Naval Research Logistics, 2009
Diffusion tensor imaging of the human calf muscle: distinct changes in fractional anisotropy and mean diffusion due to passive muscle shortening and stretching
Authors: Schwenzer Nina F. , Steidle Günter , Martirosian Petros , Schraml Christina , Springer Fabian , Claussen Claus D. , Schick Fritz
Published: July 2009

The influence of passive shortening and stretching of the calf muscles on diffusion characteristics was investigated. The diffusion tensor was measured in transverse slices through the lower leg of eight healthy volunteers (29 ± 7 years) on a 3 T whole‐body MR unit in three different positions of the foot (40° plantarflexion, neutral ankle position (0°), and −10° dorsiflexion in the ankle). Maps of the mean diffusivity, the three eigenvalues of the tensor and fractional anisotropy (FA) were calculated. Results revealed a distinct dependence of the mean diffusivity and FA on the foot position and the related shortening and stretching of the muscle groups. The tibialis anterior muscle showed a significant increase of 19% in FA with increasing dorsiflexion, while the FA of the antagonists significantly decreased (∼20%). Regarding the mean diffusivity of the diffusion tensor, the muscle groups showed an opposed response to muscle elongation and shortening. Regarding the eigenvalues of the diffusion tensor, λ2 and λ3 showed significant changes in relation to muscle length. In contrast, no change in λ1 could be found. This work reveals significant changes in diffusional characteristics induced by passive muscle shortening and stretching. Copyright © 2009 John Wiley & Sons, Ltd.
Universal three‐dimensional connection hexahedral elements based on hybrid‐stress theory for solid structures
Authors: Wu D. , Lo S. H. , Sheng N. , Sze K. Y.
Published: July 2009

High‐performance hybrid‐stress hexahedral solid elements are excellent choices for modeling joints, beams/columns walls and thick slabs for building structures if the exact geometrical representation is required. While it is straight‐forward to model beam–column structures of uniform member size with solid hexahedral elements, joining up beams and columns of various cross‐sections at a common point proves to be a challenge for structural modeling using hexahedral elements with specified dimensions. In general, the joint has to be decomposed into 27 smaller solid elements to cater for the necessary connection requirements. This will inevitably increase the computational cost and introduce element distortions when elements of different sizes have to be used at the joint. Universal connection hexahedral elements with arbitrary specified connection interfaces will be an ideal setup to connect structural members of different sizes without increasing the number of elements or introducing highly distorted elements. In this paper, the requirements and the characteristics of the hexahedral connection elements with 24 and 32 nodes will be discussed. Formulation of the connection elements by means of Hellinger–Reissner functional will be presented. The performance of connection elements equipped with different number of stress modes will be assessed with worked examples. Copyright © 2009 John Wiley & Sons, Ltd.
An Eulerian finite‐volume scheme for large elastoplastic deformations in solids
Authors: Barton P. T. , Drikakis D. , Romenski E. I.
Published: July 2009

Conservative formulations of the governing laws of elastoplastic solid media have distinct advantages when solved using high‐order shock capturing methods for simulating processes involving large deformations and shock waves. In this paper one such model is considered where inelastic deformations are accounted for via conservation laws for elastic strain with relaxation source terms. Plastic deformations are governed by the relaxation time of tangential stresses. Compared with alternative Eulerian conservative models, the governing system consists of fewer equations overall. A numerical scheme for the inhomogeneous system is proposed based upon the temporal splitting. In this way the reduced system of non‐linear elasticity is solved explicitly, with convective fluxes evaluated using high‐order approximations of Riemann problems locally throughout the computational mesh. Numerical stiffness of the relaxation terms at high strain rates is avoided by utilizing certain properties of the governing model and performing an implicit update. The methods are demonstrated using test cases involving large deformations and high strain rates in one‐, two‐, and three‐dimensions. Copyright © 2009 John Wiley & Sons, Ltd.
Do‐it‐yourself functionalized silicones part 2: synthesis by ring opening polymerization of commercial cyclosiloxanes
Authors: Yactine Bashim , Ratsimihety Amédée , Ganachaud François
Published: July 2009

The second paper of the series devoted to the preparation and characterization of vinyl and hydrido‐functionalized silicones proposes readily available techniques to polymerize commercially available cyclosiloxanes. This study is divided into two main sections: one relies on the synthesis of various functional silicone oils by heterogeneous cationic ring opening polymerization (ROP) of cyclotetrasiloxanes (D4, D) and appropriate 1,3‐difunctional disiloxanes; the second part describes the anionic ROP of hexamethylcyclotrisiloxane (D3) initiated by potassium silanolates to prepare both homo‐ and hetero‐vinyl functionalized silicones. The conditzions in which polymers with desired molecular weights can be obtained have been established and some kinetic considerations are also reported. The width of the final molar mass distribution ranged between 1.5 and 1.8, respectively, in any case narrower than the mixtures proposed by different providers (around 2). Polymers were characterized by different techniques of size exclusion chromatography (SEC), proton and silicon nuclear magnetic resonance (1H and 29Si NMR), and mass spectrometry. Copyright © 2009 John Wiley & Sons, Ltd.
Fabrication of well‐aligned electrospun nanofibrous membrane based on fluorinated polyimide
Authors: Karube Yuuki , Kawakami Hiroyoshi
Published: July 2009

We have fabricated novel nanofibrous fluorinated polyimide membranes on a specially designed collector, which is composed of conductive aluminum plates and glass insulator materials and can be removed from the apparatus, using an electrospinning method. We describe the structure and water flux properties of the nanofibrous fluorinated polyimide membranes. The electrospun nanofibers were deposited across the plates and uniaxially aligned to the collector. In addition, the multi‐layer stacked nanofibrous membranes, consisting of three‐dimensionally ordered nanopores, were produced. The pure water fluxes for the stacked membranes were measured, using a stirred dead‐end filtration cell, and were linearly decreased with an increasing deposition time, indicating that the nanopores formed in the nanofibrous membrane were further narrowed due to the regularly accumulated nanofibers. Copyright © 2009 John Wiley & Sons, Ltd.
A new method for crosslinking and reinforcing acrylonitrile–butadiene rubber using a silanized silica nanofiller
Authors: Yasin K. Ansar , Ansarifar A. , Hameed S. , Wang L.
Published: July 2009

Using a high loading of synthetic precipitated amorphous white silica nanofiller, an acrylonitrile–butadiene rubber containing 26% by weight acrylonitrile was crosslinked and its mechanical properties were measured. The silica surfaces were pre‐treated with bis(3‐triethoxysilylpropyl)tetrasulfide (TESPT) to chemically adhere silica to the rubber. To optimize the reaction between the tetrasulfane groups of TESPT and the rubber, accelerator and activator were added. The rubber was fully crosslinked and the hardness, tensile strength, stored energy density at break, elongation at break, tearing energy, and modulus increased substantially because of the filler. The bound rubber, crosslink density, tan δ, and glass transition temperature measurements indicated a strong interaction between the filler and rubber. This new method helped to substantially reduce the use of the curing chemicals and produce a safer and more cost‐effective rubber compound without compromising the good mechanical properties of the rubber, which are essential for long service life. Copyright © 2009 John Wiley & Sons, Ltd.
WT1 expression at diagnosis does not predict survival in pediatric aml: A report from the Children's Oncology Group
Authors: Noronha Suzie A. , Farrar Jason E. , Alonzo Todd A. , Gerbing Robert B. , Lacayo Norman J. , Dahl Gary V. , Ravindranath Yaddanapudi , Arceci Robert J. , Loeb David M.
Published: July 2009

WT1 is a transcription factor that is aberrantly overexpressed in acute and chronic leukemias. Overexpression of WT1 in pediatric acute myeloid leukemia has been reported, but the prognostic significance is unclear because sample sizes in these studies have been relatively small. WT1 expression was measured by quantitative RT‐PCR in samples obtained at diagnosis from 155 pediatric AML patients treated on a cooperative group protocol. Neither overall survival nor event‐free survival was correlated with WT1 expression. Pediatr Blood Cancer 2009;53:1136–1139. © 2009 Wiley‐Liss, Inc.
Inflammatory BCG adenitis associated with immune reconstitution following allogeneic haematopoietic stem cell transplant in infancy
Authors: Searle E. , Patel H. , Vilar F.J. , Gharib M. , Turner A.J. , Batra G , Wynn R.F.
Published: July 2009

We describe four cases of a localized, granulomatous reaction to BCG including ipsilateral painful, suppurative lymphadenopathy associated with donor immune reconstitution following allogeneic haematopoietic stem cell transplant performed in infancy and preceded by uneventful, routine BCG immunisation. The management of the inflammatory disease in these cases with surgery, antimycobacterial chemotherapy and steroids, is discussed. Pediatr Blood Cancer 2010; 54:166–169. © 2009 Wiley‐Liss, Inc.
Factors affecting the delivery of family‐centered care in pediatric oncology
Authors: Dix David B. , Klassen Anne F. , Papsdorf Michael , Klaassen Robert J. , Pritchard Sheila , Sung Lillian
Published: July 2009

Background

The provision of family‐centered care (FCC) emphasizes a partnership between parents and health‐care providers so that families are involved in every aspect of services for their child. Our study examines factors related to parental perception of the family‐centeredness of pediatric oncology services.

Procedure

This Canadian multi‐institutional cross‐sectional study included children with cancer receiving active treatment. One parent from each family provided information about the child, parent/family demographics, diagnosis, and treatment. FCC was measured with the MPOC‐20, a valid and reliable tool in the pediatric oncology setting that consists of two subscales: “Family‐Centered Service” and “Providing General Information.” Logistic multiple regression analyses were used to identify factors that were associated with lower ratings of FCC for each subscale.

Results

Completed questionnaires were received back from 411 parents, giving an overall response rate of 80%. Worse perceived prognosis and worse parental psychosocial health were associated with less favorable ratings for both MPOC‐20 subscales. In addition, parents who were not married or living common‐law scored lower ratings for the Family‐Centered Services subscale, whereas scores for the Provision of General Information subscale differed depending on the treatment facility at which the child received care.

Conclusions

Our study identified child/parent factors and health‐care delivery factors associated with FCC provided in the pediatric oncology setting. These results could be used as the starting point for future research looking at optimization of the FCC process. Pediatr Blood Cancer 2009;53:1079–1085. © 2009 Wiley‐Liss, Inc.
Autologous stem cell transplant in a patient with Down syndrome and relapsed Hodgkin lymphoma
Authors: Eckrich Michael J. , Domm Jennifer , Ho Richard , Whitlock James A. , Frangoul Haydar
Published: July 2009

Children with Down syndrome (DS) are at increased risk for the development of acute leukemia but they rarely develop other hematologic malignancies or solid tumors. Despite aggressive supportive care, DS patients have increased risk of treatment related morbidity and mortality compared to other children. There are few reported cases of Hodgkin disease in children with DS, and no reported cases of successful therapy for patients with relapsed disease. We report on a child with DS and relapsed Hodgkin disease who was successfully treated with high‐dose chemotherapy and autologous stem cell transplant. Pediatr Blood Cancer 2009; 53:1327–1328. © 2009 Wiley‐Liss, Inc.
Characterisation of Phenolics in Flor‐Essence®—a Compound Herbal product and its Contributing Herbs
Authors: Saleem Ammar , Walshe‐Roussel Brendan , Harris Cory , Asim Muhammad , Tamayo Carmen , Sit Summer , Arnason John Thor
Published: July 2009

Introduction – Commercially available herbal mixture FE, a proprietary natural health product manufactured by Flora Manufacturing and Distributing Ltd (Flora), is a unique North American traditional herbal product. FE is a chemically complex mixture of eight herbs and has not been subjected to phytochemical analysis.

Objective – To develop analytical methods to undertake detailed phytochemical analyses of FE, and its eight contributing herbs, including burdock (Arctium lappa L.), sheep sorrel (Rumex acetosella L.), Turkish rhubarb (Rheum palmatum L.), slippery elm Muhl. (Ulmus rubra), watercress (Nasturtium officinale R. Br.), red clover (Trifolium pratense L.), blessed thistle (Cnicus benedictus L.) and kelp (Laminaria digitata Lmx.).

Methodology – The identification was undertaken by a combination of reversed phase high performance liquid chromatography–diode array detection–atmospheric pressure chemical ionisation–mass selective detection (RP‐HPLC‐DAD‐APCI‐MSD) analysis and phenolics metabolomic library matching.

Results – New separation methods facilitated the identification of 43 markers in the individual herbs which constitute FE. Sixteen markers could be identified in FE originating from four contributing herbs including four caffeoyl quinic acids, three dicaffeoyl quinic acids and two caffeic acid derivatives from A. lappa, luteolin‐7‐O‐glucoside, luteolin, five apigenin glycosides and apigenin from R. acetocella and N. officinale and sissostrin from T. pretense. A validated method for quantitative determination of three markers is reported with good intraday, interday and interoperator repeatability using a reliable alcohol based extraction technique.

Conclusion – FE and its contributing herbs predominantly contain phenolics. This methodology can be applied to further develop full‐scale validation of this product. Copyright © 2009 John Wiley & Sons, Ltd.
Validation of a quantitative assay of arbutin using gas chromatography in Origanum majorana and Arctostaphylos uva‐ursi extracts
Authors: Lamien‐Meda Aline , Lukas Brigitte , Schmiderer Corinna , Franz Chlodwig , Novak Johannes
Published: July 2009

Introduction – Arbutin is a skin‐whitening agent that occurs naturally in the bark and leaves of various plants. It is commonly quantified in plant extracts and skin‐whitening products by HPLC.

Objective – To develop an alternative gas chromatographic method for the separation and quantification of arbutin in Origanum majorana and Arctostaphylos uva‐ursi extracts.

Methodology – N,O‐Bis(trimethylsilyl)acetamide and trimethylchlorosilane were used as silylation reagents, and the gas chromatographic separation of silylated extracts and standards was performed using a DB‐5 narrow bore column. GC‐MS was used for the compound identification, and the quantification was carried out by GC‐FID. The quantitative results were compared with those of HPLC analysis.

Results – The developed method gave a good sensitivity with linearity in the range 0.33–500 mg/mL and recovery >98%, allowing the quantification of arbutin in O. majorana and A. uva‐ursi extracts. The relative standard deviations (RSD) relating to intra‐day and inter‐day precision were <0.002% and <4.8%, respectively. The GC results correlated well with those obtained by HPLC analysis.

Conclusion – The analysis of marjoram and bearberry samples showed that the established GC method was rapid, selective, and demonstrated that arbutin could be screened alternatively by gas chromatography. Copyright © 2009 John Wiley & Sons, Ltd.
A qualitative and quantitative HPTLC densitometry method for the analysis of cannabinoids in Cannabis sativa L.
Authors: Fischedick Justin T. , Glas Ronald , Hazekamp Arno , Verpoorte Rob
Published: July 2009

Introduction – Cannabis and cannabinoid based medicines are currently under serious investigation for legitimate development as medicinal agents, necessitating new low‐cost, high‐throughput analytical methods for quality control.

Objective – The goal of this study was to develop and validate, according to ICH guidelines, a simple rapid HPTLC method for the quantification of Δ9‐tetrahydrocannabinol (Δ9‐THC) and qualitative analysis of other main neutral cannabinoids found in cannabis.

Methodology – The method was developed and validated with the use of pure cannabinoid reference standards and two medicinal cannabis cultivars. Accuracy was determined by comparing results obtained from the HTPLC method with those obtained from a validated HPLC method.
Results – Δ9‐THC gives linear calibration curves in the range of 50–500 ng at 206 nm with a linear regression of y = 11.858x + 125.99 and r2 = 0.9968.

Conclusion – Results have shown that the HPTLC method is reproducible and accurate for the quantification of Δ9‐THC in cannabis. The method is also useful for the qualitative screening of the main neutral cannabinoids found in cannabis cultivars. Copyright © 2009 John Wiley & Sons, Ltd.
Jasminum polyanthum Franch. as a natural source of (−)‐methyl jasmonate: an alternative to the use of the synthetic standard
Authors: Blanch Gracia Patricia , Flores Gema , del Mar Caja Maria , Ruiz del Castillo Maria Luisa
Published: July 2009

Introduction – Methyl jasmonate (MJ) contains two chiral centres at C‐3 and C‐7 in its chemical structure, which implies that it can exist in four possible stereoisomeric forms, namely (+)‐MJ, (−)‐MJ, (+)‐epiMJ and (−)‐epiMJ. The absolute configuration of the two side chains of MJ affects the biological activity associated with this compound.

Objective – To isolate pure (−)‐MJ from a natural source, Jasminum polyanthum Franch., with the intention of increasing the knowledge about its biological properties, including its effect on the biosynthesis of plant metabolites.

Methodology – The method used was based on steam distillation extraction (SDE) as an extraction technique followed by high‐performance liquid chromatography (HPLC) as a purification procedure. The HPLC flow‐rate as well as the number of fractions accumulated were optimised to achieve the concentration and purity required.

Results – The employment of 0.3 mL/min as HPLC flow‐rate and the accumulation of three HPLC fractions allowed the required enantiomeric purity (95%) and concentration (0.36 mg/L in each HPLC fraction) to efficiently obtain (−)‐methyl jasmonate from Jasminum polyanthum Franch. to be achieved.

Conclusion – The approach proposed may enable the properties and effect of pure (−)‐MJ on plant responses to be studied. The use of a natural source to obtain (−)‐MJ is presented as an alternative to the enantioselective synthesis and enantiomeric resolution from the standard racaemic mixture. Copyright © 2009 John Wiley & Sons, Ltd.
Identification of a naturally‐occurring 8‐[α‐D‐glucopyranosyl‐(1→6)‐β‐D‐glucopyranosyl]daidzein from cultivated kudzu root
Authors: Nguyen Van Dao , Min Byoung‐Cheol , Kyung Myung‐Ok , Park Jong‐Tae , Lee Byong Hoon , Choi Chung‐Hyo , Seo Nam‐Seok , Kim Yong‐Ro , Ahn Dong Uk , Lee Sung‐Joon , Park Cheon‐Seok , Kim Jung‐Wan , Park Kwan‐Hwa
Published: July 2009

Introduction – Kudzu root (Radix puerariae) is a rich source of isoflavones that are effective in preventing osteoporosis, heart disease and symptoms associated with menopause. The major isoflavonoids in kudzu root extracts were reported as puerarin, daidzin and daidzein. Recently, an unknown isoflavonoid (compound 1) was detected from one‐year‐old kudzu root cultivated in Vietnam.

Objective – To identify a novel compound 1 in kudzu root extract and determine the structure of the compound by ESI+ TOF MS‐MS, 1H‐, 13C‐NMR and enzymatic hydrolysis.

Methodology – Samples were prepared by extraction of one‐year‐old kudzu root with 50% ethanol and the isoflavonoids were purified using recycling preparative HPLC. Unknown compound 1 was detected using UV‐light at 254 nm in TLC and HPLC analyses. The molecular weight of 1 was determined using a TOF mass spectrometer equipped with an electrospray ion source. The structure of 1 was determined from the 13C and 1H NMR spectra recorded at 100.40 and 400.0 MHz, respectively.

Results – ESI+ TOF MS‐MS analysis shows that 1 is a puerarin diglycoside. The interglycosidic linkage of diglycoside determined by 1H‐, 13C‐NMR, and enzymatic hydrolysis suggests that 1 has a glucosyl residue linked to puerarin by an α‐1,6‐glycosidic bond. This compound is the first naturally‐occurring 8‐[α‐D‐glucopyranosyl‐(1→6)‐β‐D‐glucopyranosyl]daidzein in kudzu root. The concentration of glucosyl‐α‐1,6‐puerarin in kudzu root was 2.3 mg/g as determined by HPLC.

Conclusion – The results indicate that puerarin diglycoside is one of the major isoflavonoids in kudzu root and has a significant impact on the preparation of highly water‐soluble glycosylated puerarin. Copyright © 2009 John Wiley & Sons, Ltd.
What can primary care prescribing data tell us about individual adherence to long‐term medication?—comparison to pharmacy dispensing data
Authors: Mabotuwana Thusitha , Warren Jim , Harrison Jeff , Kenealy Timothy
Published: July 2009

Purpose

To assess the predictive value of general practice electronic prescribing records with respect to adherence to long‐term medications as compared to claims‐based pharmacy dispensing data.

Methods

A total of 29772 electronic prescribing records relating to 2713 patients attending a New Zealand general medical practice were linked by national health identifier to 63 833 dispensing records used for community pharmacy reimbursement. Individual possession ratios—prescription possession ratio (PPR) for prescribing and medication possession ratio (MPR) for dispensing—were calculated for the 15‐month period from 1 January 2006 to 30 March 2007 based on each data source for the common long‐term medications simvastatin, metoprolol succinate, bendrofluazide, felodipine, cilazapril and metformin.

Results

Out of 646 patients prescribed at least one of the six medications by the practice during the 15‐month period, 50% of patients maintained high adherence (MPR ≥ 80%) to all (out of the 6) medications that they were prescribed over the period, with rates of high adherence to individual medications ranging from 68 (felodopine) to 55% (metformin). In 93% of 4043 cases where there was a prescription in the general practice data, a subsequent dispensing record for the same patient and drug was present with a time‐stamp no more than seven days later. PPR < 80% demonstrated a positive predictive value (PPV) of 81.4% (95%CI 78–85%) and negative predictive value (NPV) of 76.3% (95%CI 73–79%) for MPR < 80%.

Conclusion

There is potential for general practices to identify substantial levels of long‐term medication adherence problems through their electronic prescribing records. Significant further adherence problems could be detected if an e‐pharmacy network allowed practices to match dispensing against prescriptions. Copyright © 2009 John Wiley & Sons, Ltd.
Dispersion of cellulose crystallites by nonionic surfactants in a hydrophobic polymer matrix
Authors: Kim Jooyoun , Montero Gerardo , Habibi Youssef , Hinestroza Juan P. , Genzer Jan , Argyropoulos Dimitris S. , Rojas Orlando J.
Published: July 2009

Cellulose nanoparticles obtained by acid hydrolysis of cellulose paper were used to reinforce polystyrene composite films. The nonionic surfactant sorbitan monostearate was utilized to improve the dispersion properties of the hydrophilic cellulose in hydrophobic matrix and to prevent the formation of aggregates. Turbidity tests were used to measure dispersion stability of the cellulose crystallites in the hydrophobic solvent used in the composite manufacture. A correlation was found between the dispersion stability in solvent and the formation of aggregates in the polymeric composites. Nanocomposite films were processed using a casting/evaporation technique. Thermal and mechanical properties of processed composites were studied by differential scanning calorimetry (DSC) and dynamical mechanical analyses (DMA), respectively. The results showed that the optimum addition of surfactant produced better dispersion of the cellulose particles in the polystyrene matrix and improved the mechanical properties of the resulting composite due to an enhanced compatibility. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
A parametric study on the processing parameters and properties of a porous poly(DL‐lactide‐co‐glycolide) acid 85/15 bioscaffolds
Authors: Perron Josee K. , Naguib Hani E. , Daka Joseph , Chawla Attar
Published: July 2009

This study presents a comprehensive parametric study on the effects of processing parameters on the poly(DL‐lactide‐co‐glycolide) acid (PLGA) 85/15 scaffold's physical properties. Porous PLGA 85/15 scaffolds were prepared using a gas foaming/salt leaching technique. The processing parameters under examination for the gas foaming/salt leaching method included: gas saturation pressure (SP), gas saturation time, and NaCl/polymer mass ratio (NaCl/PMR). The physical properties considered in this study were the scaffold density, the scaffold porosity, and the average pore size of the scaffold. Young's moduli in compression, as well as the pore density (PD) inside the scaffold, were also studied. The results demonstrated optimum correlations of processing parameters are required to produce a scaffold with a high level of interconnectivity. In general, all scaffolds yielded by this experiment exhibited a porosity more than 90%, a relative density ranging from 0.0534 to 0.149 g/cm3, a PD ranging from 1.51 × 106to 6.72 × 106pores/cm3, and a compressive modulus ranging from 0.07 to 0.84 MPa. It was determined that the NaCl/PMR was the parameter that had the most significant effect on the physical properties of the scaffold. The average pore size was affected slightly by the SP only, and it was observed that the pore size was equivalent to the size of the NaCl particles used to make the scaffold. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Microemulsion copolymerization of styrene‐methyl methacrylate followed on line by low‐resolution Raman spectroscopy
Authors: Corona‐Rivera Miguel A. , Flores Jorge , Puig Jorge E. , Mendizábal Eduardo
Published: July 2009

In this work, the kinetics of microemulsion copolymerization of styrene (St) and methyl methacrylate (MMA) at 60°C using dodecyltrimethylammonium bromide (DTAB) as the surfactant was followed on line by low‐resolution Raman spectroscopy. Raman spectra were taken every 30 s. Because the spectrophotometer has low resolution, the CC peak overlaps with the St aromatic ring stretch vibration and curve deconvolution was necessary. Overall conversion obtained by Raman spectroscopy agrees with that obtained by gravimetry. Copolymer composition was determined by following the area changes of the COC bending mode peak of MMA. Compositions determined by this method agree with those measured by NMR spectroscopy. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Incipient stable bubble formation during bulk polymerization of methyl methacrylate under near‐isothermal conditions. II. Use of an anchor agitator
Authors: Singh Gurpreet J. , Gupta Santosh K.
Published: July 2009

Methyl methacrylate is polymerized under near‐isothermal conditions in a 1‐l stainless steel batch reactor having a glass bottom and stirred with an anchor agitator. A camcorder is used to obtain images of the entrapped vapor bubbles at different times so as to identify the point, Bi, where stable clusters of vapor bubbles first (incipient) get formed. This is being referred to as the transition point. Data on the monomer conversion, xm,Bi, the weight average molecular weight, Mw,Bi, and the viscosity, ηBi, of the reaction mass at this point have been generated for a variety of experimental conditions. It is observed that the pressure above the liquid reaction mixture and the RPM of the stirrer have little effect on the results in the ranges studied. Correlations have been developed for xm,Bi, Mw,Bi, and ηBi, relating these to the initiator loading, Io, and the constant set‐point temperature, T. Results are compared with those obtained earlier for reactors stirred with ribbon agitators. The transition point is useful for the design of the first stage of polymerization reactors. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Isolation of intact proteins from acid‐degradable polyacrylamide gel
Authors: Kim Yoon Kyung , Kwon Young Jik
Published: July 2009

Elucidating native structure–function relationships of proteins identified using PAGE has been impeded by limitations in the isolation of intact proteins from the gel. By hydrolyzing polyacrylamide gel band under mildly acidic conditions rather than digesting entrapped proteins ∼70% of a large native protein, mouse IgG1 (molecular weight 150 kDa), was isolated. Further analysis indicated that the isolated antibodies had preserved specific binding capability to target antigens as well as intact molecular weights. This new technology may contribute to functional proteomic studies through the isolation of proteins in their native state after PAGE, and other technologies requiring simultaneous separation and isolation of other macromolecules and complexes.
Wellcome Trust/EBI 2009 Meeting Report – Perspectives in Stem Cell Proteomics 22–23 March 2009, Wellcome Trust Conference Centre, Hinxton, UK
Authors: de Wynter Erika , Unwin Richard
Published: July 2009

This report summarises the recent “Perspectives in Stem Cell Proteomics” meeting that was held at the Wellcome Trust Conference Centre, Hinxton, UK in March 2009. The aim of the meeting was to explore the current status of proteomics in stem cell biology. Several themes encompassing technological and biological studies demonstrated the close relationship that must exist between the two communities in order to maximise our understanding of stem cell behaviour. Highlights included new methods for induction of pluripotent stem cells, new data sets regarding protein expression and phosphorylation dynamics in differentiating cells and the potential for future exploitation in a therapeutic setting.
Recent Advances in the Atmospheric Pressure PE‐CVD of Fluorocarbon Films: Influence of Air and Water Vapour Impurities
Authors: Fanelli Fiorenza , Di Renzo Giovanni , Fracassi Francesco , d'Agostino Riccardo
Published: July 2009

The influence of air and water vapour on the deposition process of fluoropolymers in argon‐hexafluoropropene (Ar‐C3F6) filamentary dielectric barrier discharges was investigated by adding known concentrations of these contaminants to the feed gas. The obtained results show that Ar‐C3F6 DBDs allow in depositing thin films with a XPS F/C ratio as high as 1.7. Under the experimental conditions investigated, contaminant addition slightly affects the F/C ratio of the coatings, and does not cause appreciable O‐ and N‐uptake, but induces a decrease of the deposition rate. Preliminary results from the OES investigation of the gas phase and the GC‐MS analysis of the gas effluent are also reported.
Analysis of loop boundaries using different local structure assignment methods
Authors: Tyagi Manoj , Bornot Aurélie , Offmann Bernard , de Brevern Alexandre G.
Published: July 2009

Loops connect regular secondary structures. In many instances, they are known to play important biological roles. Analysis and prediction of loop conformations depend directly on the definition of repetitive structures. Nonetheless, the secondary structure assignment methods (SSAMs) often lead to divergent assignments. In this study, we analyzed, both structure and sequence point of views, how the divergence between different SSAMs affect boundary definitions of loops connecting regular secondary structures. The analysis of SSAMs underlines that no clear consensus between the different SSAMs can be easily found. Because these latter greatly influence the loop boundary definitions, important variations are indeed observed, that is, capping positions are shifted between different SSAMs. On the other hand, our results show that the sequence information in these capping regions are more stable than expected, and, classical and equivalent sequence patterns were found for most of the SSAMs. This is, to our knowledge, the most exhaustive survey in this field as (i) various databank have been used leading to similar results without implication of protein redundancy and (ii) the first time various SSAMs have been used. This work hence gives new insights into the difficult question of assignment of repetitive structures and addresses the issue of loop boundaries definition. Although SSAMs give very different local structure assignments capping sequence patterns remain efficiently stable.
Solubilization and characterization of the anthrax toxin pore in detergent micelles
Authors: Vernier Gregory , Wang Jie , Jennings Laura D. , Sun Jianjun , Fischer Audrey , Song Likai , Collier R. John
Published: July 2009

Proteolytically activated Protective Antigen (PA) moiety of anthrax toxin self‐associates to form a heptameric ring‐shaped oligomer (the prepore). Acidic pH within the endosome converts the prepore to a pore that serves as a passageway for the toxin's enzymatic moieties to cross the endosomal membrane. Prepore is stable in solution under mildly basic conditions, and lowering the pH promotes a conformational transition to an insoluble pore‐like state.N‐tetradecylphosphocholine (FOS14) was the only detergent among 110 tested that prevented aggregation without dissociating the multimer into its constituent subunits. FOS14 maintained the heptamers as monodisperse, insertion‐competent 440‐kDa particles, which formed channels in planar phospholipid bilayers with the same unitary conductance and ability to translocate a model substrate protein as channels formed in the absence of detergent. Electron paramagnetic resonance analysis detected pore‐like conformational changes within PA on solubilization with FOS14, and electron micrograph images of FOS14‐solubilized pore showed an extended, mushroom‐shaped structure. Circular dichroïsm measurements revealed an increase in α helix and a decrease in β structure in pore formation. Spectral changes caused by a deletion mutation support the hypothesis that the 2β2‐2β3 loop transforms into the transmembrane segment of the β‐barrel stem of the pore. Changes caused by selected point mutations indicate that the transition to α structure is dependent on residues of the luminal 2β11‐2β12 loop that are known to affect pore formation. Stabilizing the PA pore in solution with FOS14 may facilitate further structural analysis and a more detailed understanding of the folding pathway by which the pore is formed.
The GD box: A widespread noncontiguous supersecondary structural element
Authors: Alva Vikram , Dunin‐Horkawicz Stanislaw , Habeck Michael , Coles Murray , Lupas Andrei N.
Published: July 2009

Identification and characterization of recurrent supersecondary structural elements is central to understanding the rules governing protein tertiary structure. Here, we describe the GD box, a widespread noncontiguous supersecondary element, which we initially found in a group of topologically distinct but homologous β‐barrels—the cradle‐loop barrels. The GD box is similar both in sequence and structure and comprises two short unpaired β‐strands connected by an orthogonal type‐II β‐turn and a noncontiguous β‐strand forming hydrogen bonds with the β‐turn. Using structure‐based analysis, we have detected 518 instances of the GD box in a nonredundant subset of the SCOP database comprising 3771 domains. Apart from the cradle‐loop barrels, this motif is also found in a diverse set of nonhomologous folds including other topologically related β‐barrels. Since nonlocal interactions are fundamental in the formation of protein structure, systematic identification and characterization of other noncontiguous supersecondary structural elements is likely to prove valuable to protein structure modeling, validation, and prediction.
Comparative surface geometry of the protein kinase family
Authors: Thompson Elaine E. , Kornev Alexandr P. , Kannan Natarajan , Kim Choel , Ten Eyck Lynn F. , Taylor Susan S.
Published: July 2009

Identifying conserved pockets on the surfaces of a family of proteins can provide insight into conserved geometric features and sites of protein–protein interaction. Here we describe mapping and comparison of the surfaces of aligned crystallographic structures, using the protein kinase family as a model. Pockets are rapidly computed using two computer programs, FADE and Crevasse. FADE uses gradients of atomic density to locate grooves and pockets on the molecular surface. Crevasse, a new piece of software, splits the FADE output into distinct pockets. The computation was run on 10 kinase catalytic cores aligned on the αF‐helix, and the resulting pockets spatially clustered. The active site cleft appears as a large, contiguous site that can be subdivided into nucleotide and substrate docking sites. Substrate specificity determinants in the active site cleft between serine/threonine and tyrosine kinases are visible and distinct. The active site clefts cluster tightly, showing a conserved spatial relationship between the active site and αF‐helix in the C‐lobe. When the αC‐helix is examined, there are multiple mechanisms for anchoring the helix using spatially conserved docking sites. A novel site at the top of the N‐lobe is present in all the kinases, and there is a large conserved pocket over the hinge and the αC‐β4 loop. Other pockets on the kinase core are strongly conserved but have not yet been mapped to a protein–protein interaction. Sites identified by this algorithm have revealed structural and spatially conserved features of the kinase family and potential conserved intermolecular and intramolecular binding sites.
A semiquantitative risk assessment methodology to prioritize recommendations
Authors: Bhimavarapu Kumar R. , Doerr William W.
Published: July 2009

Process safety engineers promote loss prevention by providing recommendations when deficiencies are observed. Deficiencies are undesirable conditions that aggravate the likelihood and/or the severity of loss events. Any improvement needs resources, and since the resources are always limited, process safety engineers have to establish priorities for loss prevention recommendations. One appropriate way to prioritize the recommendations is to evaluate and compare the cost of risk reduction associated with the improvements. While qualitative risk analysis techniques may not be able to provide the necessary resolution to differentiate the improvements, quantitative techniques need much expertise, time, and funds. A feasible approach would be a semiquantitative methodology with the simplifications necessary to make it easy to use, but at the same time providing the needed resolution for prioritization. This article presents such a methodology to prioritize loss prevention recommendations. The methodology uses the concept of engineered systems, which are simply hardware (equipment or facility), procedures, or a combination put in place to serve specific functional intents. The basis of the methodology is founded in the premise that deficiencies are always associated with engineered systems and deficiencies increase their failure likelihoods. A few examples are provided with the details of the methodology and the incorporated simplifications. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009
Core models of a‐edge threading dislocations in wurtzite III(Al,Ga,In)‐nitrides
Authors: Kioseoglou J. , Komninou Ph. , Karakostas Th.
Published: July 2009

An empirical bond‐order many body interatomic Tersoff potential is used for atomistic calculations of the multiple atomic configurations (5/7, 8 and 4) of the a‐edge threading dislocations in III(Al,Ga,In)‐N compound semiconductors. Structural‐ and energy‐related conclusions are drawn which are attributed to the complexity of the III–III metal type and N–N interactions (bondGa–Ga < bondAl–Al < bondIn–In) in connection with the difference of the lattice parameters (aAlN < aGaN < aInN) and the elastic constants. The 5/7‐atomic core configuration is calculated as the most energetically and structurally favourable in all the three compounds. Taking the 5/7‐atom model as a reference, the 8‐atom core model becomes the next favourable one when the lattice parameter increases (aInN) while the 4‐atom core model is the second energetically favourable when the lattice parameter decreases (aAlN).
Polar AlN/GaN interfaces: Structures and energetics
Authors: Kioseoglou J. , Kalesaki E. , Lymperakis L. , Dimitrakopulos G. P. , Komninou Ph. , Karakostas Th.
Published: July 2009

The structures and energies of {0001} interfaces between GaN and AlN are studied by both ab initio methods and molecular dynamics using the Tersoff empirical inter‐atomic potential. Based on experimental observations, structural configurations depending on polarity and atomic stacking are considered. It is evidenced by both ab initio and empirical calculations that III‐polar interfaces are energetically favourable compared to the N‐polar. In addition, the ab initio analysis shows that the wurtzite interfacial stacking is energetically preferable compared to zinc blende. A linear dependence between the bandgap energy and the strain in AlN/GaN heterostructures is found. It is shown that the bandgap increases with increasing c/a ratio while an inverse proportionality relationship is observed in the case of lattice parameter a. However, biaxial strain is found to flatten this variation considerably. Empirical potential calculations yield the interfacial energies, taking into account the relaxation of the lattice mismatch due to arrays of misfit dislocations and in combination with ab initio methods estimate that the energetically favourable III polarity interface exhibits at least 18% larger critical thickness than the N polar.