bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective enrichment with “click oligo (ethylene glycol)” column and TOF–MS characterization of simple phenylpropanoids in the fruits of Forsythia suspensa
Authors: Wang Yaqin , Guo Zhimou , Jin Yu , Zhang Xiuli , Li Wei , Liang Xinmiao 
Published: August 2009

AbstractTo separate samples of complex natural products, highly efficient and selective separation methods should be developed. Herein, a selective enrichment method was developed to separate Forsythia suspensa components with “click oligo (ethylene glycol)” (OEG) column in reversed phase (RP) mode. In this method, F. suspensa aqueous extract was successfully separated. And three fractions with structure‐related compounds were obtained. Fraction I mainly consisted of C6–C2 natural alcohols and glycosides, fraction II mostly consisted of lignans, and fraction III mainly consisted of simple phenylpropanoids (SP). Then, the three fractions were separated with ultra‐performance liquid chromatography (UPLC). Four more lignans were observed in fraction II, and eight more SP were observed in fraction III than that without OEG column. Fraction III was successively characterized by TOF–MS, 2 acids (caffeic acid and chlorogenetic acid), 26 SP with caffeoyl, and 2 SP with coumaroyl were characterized. The results prove that a valid method has been developed to selectively enrich SP and lignans. And the method combined with UPLC can efficiently separate SP and lignans. Furthermore, the TOF–MS method is effective to confirm the substituents of SP.
Preparation and HPLC application of chiral stationary phase from 4‐tert‐butylphenylcarbamates of cellulose and amylose immobilized onto silica gel
Authors: Li Jun‐qing , Ikai Tomoyuki , Okamoto Yoshio 
Published: August 2009

AbstractThe 4‐tert‐butylphenylcarbamates of cellulose and amylose bearing a small amount of 3‐(triethoxysilyl)propyl residues were synthesized by a one‐pot process and efficiently immobilized onto a silica gel through intermolecular polycondensation of the triethoxysilyl groups. The obtained chiral packing materials (CPMs) were evaluated by HPLC. The polysaccharide derivatives containing about 1–2% of the 3‐(triethoxysilyl)propyl residue were efficiently immobilized with a high chiral recognition ability. The immobilized CPMs could be used with the eluents containing chloroform and tetrahydrofuran (THF), which cannot be used with the conventional coated‐type CPMs. By using these eluents, the chiral recognition for many racemates was improved.
Prediction of the chromatographic signal in gradient elution ion chromatography
Authors: Bolanča Tomislav , Stefanović Štefica Cerjan , Ukić Šime , Rogošić Marko , Luša Melita 
Published: August 2009

AbstractThis study describes the development of a signal prediction model in gradient elution ion chromatography. The proposed model is based on a retention model and generalized logistic peak shape function which guarantees simplicity of the model and its easy implementation in method development process. Extensive analysis of the model predictive ability has been performed for ion chromatographic determination of bromate, nitrite, bromide, iodide, and perchlorate, using KOH solutions as eluent. The developed model shows good predictive ability (average relative error of gradient predictions 1.94%). The developed model offers short calculation times as well as low experimental effort (only nine isocratic runs are used for modeling).
The management of obesity
Authors: Stanley John C. 
Published: August 2009

AbstractThe prevalence and incidence of obesity is rising as current ways of managing obesity are proving to be ineffective. The preferred approach is to induce an energy deficit by decreasing energy intake through a low calorie diet and increasing energy expenditure through exercise. In order to provoke body weight loss the changes in lifestyle that this approach involves have to be sustained and while some individuals have the motivation to do this the vast majority of the population has not. Very low calorie diets are ineffective as the body adapts to them by lowering energy expenditure and altering the macronutrient composition of low calorie diets has no additional effect. The anti‐obesity drugs orlistat, sibutramine and rimonabant can provoke body weight loss but all suffer from side effects. However, the explosion in our understanding of the factors that regulate energy intake is likely to lead to the development of more effective drugs with fewer side effects. Bariatric or weight reducing surgery is highly effective at provoking body weight loss but there are obvious barriers to its widespread use.
The Design of Biodegradable Microcarriers for Induced Cell Aggregation
Authors: Tan Huaping , Wu Jindan , Huang Dejuan , Gao Changyou 
Published: August 2009

AbstractPLLA microspheres were aminolyzed in hexanediamine/propanol solution to introduce free amino groups on their surface, which were further transferred into aldehyde groups by a treatment of glutaraldehyde. Chitosan‐graft‐lactose was then covalently coupled via Schiff base formation. Morphological variation and chitosan‐graft‐lactose immobilization were characterized. In vitro culture of rabbit auricular chondrocytes demonstrated that the PLLA microcarriers could effectively support the cell attachment and particularly induce cell aggregation on their surface. The formed cell aggregates/microcarriers composite showed higher viability and extracellular matrix production. Thus, the PLLA microcarriers can be potentially used as an injectable delivery system for cartilage repair.magnified image
Self‐Assembly Behavior and Optical Properties of Poly(3‐thiopheneacetate)/Dialkyldimethylammonium Complexes
Authors: Yoon Young‐Sik , Park Kwang‐Han , Lee Jong‐Chan 
Published: August 2009

AbstractPoly(3‐thiopheneacetate)/dialkyldimethylammonium complexes (PTA‐Cn) were prepared by mixing regiorandom poly(3‐thiopheneacetic acid) with dialkyldimethylammonium bromide to study the effect of their self‐assembled structures on the optical properties. The lengths of the alkyl groups in the ammonium salts were varied from decyl (C10) to octadecyl (C18) groups. These complexes showed fully developed layer structures with ordered mesophases. PTA‐C16 and PTA‐C18 with longer alkyl groups showed side‐chain crystalline phases, and PTA‐C10, PTA‐C12, and PTA‐C14 with shorter alkyl groups showed side‐chain crystalline and liquid crystalline phases at room temperature. When PTA‐C18 was heated, a melting transition from side‐chain crystalline to smectic liquid crystalline phase was observed at 41.5 °C. The maximum absorption and emission wavelengths of these complexes increased with increasing alkyl chain length indicating that the π‐conjugated structure of the regiorandom thiophene backbone changes according to the alkyl groups.magnified image
A Phase Blending Study on Rubber Blends Based on the Solubility Preference of Curatives
Authors: Guo Rui , Talma Auke G. , Datta Rabin N. , Dierkes Wilma K. , Noordermeer Jacques W. M. 
Published: August 2009

AbstractUsing previously obtained data on the solubilities of curatives in SBR, EPDM and in NBR, different mixing procedures were performed on 50/50 SBR/EPDM and NBR/EPDM blends. In contrast to a previous phase‐mixing study, the curatives were added to separate phases before final blending, in an attempt to control the curative distributions in the blends for optimal mechanical properties. Fillers were not applied in the system to exclude their influence on the dispersion of the curatives. The properties of such blends compounded by selective phase mixing are superior to those of blends compounded with normal mixing procedures.magnified image
Fabrication of Aligned Poly(L‐lactide) Fibers by Electrospinning and Drawing
Authors: Afifi Amalina M. , Nakajima Hajime , Yamane Hideki , Kimura Yoshiharu , Nakano Shigeyuki 
Published: August 2009

AbstractA new target collector was designed for taking up aligned nanofibers by electrospinning. The collector consists of a rotor around which several fins were attached for winding electrospun filaments continuously in large amounts. The alignment of the nanofibers wound on the collector was affected by the electrospinning conditions, such as the needle‐to‐collector distance and the applied voltage, but not by the rotation speed of the collector. At a voltage of 0.5 kV · cm−1, about 60% of the fibers were found to be aligned within an angle of ± 5° relative to the rotational direction of the collector. The fiber alignment was improved to 90% by drawing the fiber bundle 2–3 times at 110 °C. The drawing was also effective for crystal orientation of the fibers as revealed by WAXD. The drawn fibers show improved mechanical properties.magnified image
Acorn‐Shape Polymeric Nano‐Colloids: Synthesis and Self‐Assembled Films
Authors: Misra Anuradha , Urban Marek W. 
Published: August 2009

AbstractThese studies show for the first time that the synthesis of two distinct phase‐separated copolymers within one colloidal particle, i.e., poly(methyl methacrylate) (PMMA)/n‐butylacrylate (nBA) and poly(nBA)/pentafluorostyrene (p‐PFS) phases, results in unique acorn‐shaped morphologies and are capable of coalescence. Spectroscopic and morphological analysis combined with contact angle measurements as well as thermodynamic modeling reveal that in an effort to create stable heterogeneous two‐phase particle morphologies it is essential to provide desirable interfacial energetic conditions during polymerization and to utilise monomers that have a similar glass transition temperature (Tg). Such colloidal particles are stable and are able to self‐assemble during coalescence, depending upon the surface energy of a substrate. When a particle monolayer coalesces on a high surface tension substrate, the p‐PFS phase expresses itself near the film–air interface, whereas for low surface energy substrates, the p‐PFS phase dominates the film–substrate interfacial regions.magnified image
Precise Control of Photoinduced Birefringence in Azobenzene‐Containing Liquid‐Crystalline Polymers by Post Functionalization
Authors: Yu Haifeng , Kobayashi Takaomi , Ge Ziyi 
Published: August 2009

AbstractA series of functionalized liquid‐crystalline polymer materials with different degrees of functionality was synthesized by a post Sonogashira cross‐coupling reaction of a polymer precursor. The post‐functionalization was carried out under mild conditions and showed a high yield. Although a highly birefringent azotolane group was introduced into the polymer precursor, the photoresponse of the functionalized liquid‐crystalline materials was not obviously changed. By adjusting the content of azotolane groups, precise control of the photoinduced birefringence was successfully obtained after thermal enhancement upon annealing. The present method to gain precise control of photoinduced birefringence might enable one to finely photocontrol the optical performances of materials, and may have a potential application as an advanced process for photonic materials.magnified image
Model Development and Validation of Crystallization Behavior in Injection Molding Prototype Flows
Authors: Custódio Frederico J. M. F. , Steenbakkers Rudi J. A. , Anderson Patrick D. , Peters Gerrit W. M. , Meijer Han E. H. 
Published: August 2009

AbstractTo control the final properties of semi‐crystalline polymer products, an accurate prediction of the material microstructure developed upon processing is required. For that purpose a model for flow‐enhanced nucleation of semi‐crystalline polymers is proposed, which relates molecular deformation with the enhancement of crystallization. Flow kinematics, computed in a decoupled fashion, are used to solve a coupled viscoelastic stress—crystallization problem. Morphological features concerning the number, size, and shape of crystalline structures are predicted and a comparison is made with experimental results reported by Housmans et al.1,2 in which the morphology development of an isotactic polypropylene (iPP) resin was studied.magnified image
New insights into small‐molecule inhibitors of Bcr‐Abl
Authors: Schenone S. , Bruno O. , Radi M. , Botta M. 
Published: August 2009

AbstractChronic myelogenous leukemia (CML) is a myeloproliferative disease associated with a defined genetic abnormality, the Bcr‐Abl fusion gene on the Philadelphia chromosome that expresses the constitutively activated tyrosine kinase (TK) Bcr‐Abl. This enzyme leads to the malignant transformation of primitive hematopoietic cells and to the consequent disease. The central role of Bcr‐Abl in the pathogenesis of CML culminated in the discovery of imatinib (an ATP‐competitive inhibitor), which is currently the frontline therapy for CML. Unfortunately, the initial enthusiasm generated by its high response rate has been dampened by the development of resistance, especially in the advanced phases of CML. To overcome imatinib resistance, several second‐generation ATP‐competitive inhibitors endowed with increased potency against imatinib‐resistant mutants have been developed: the dual Src/Abl inhibitor dasatinib and the Abl inhibitor nilotinib have been recently approved by US‐FDA for the treatment of imatinib‐resistant CML, and many other compounds are currently in clinical trial. Although second‐generation TK inhibitors have shown to be clinically effective against most of the imatinib‐resistant mutants, to date poor results have been obtained in the treatment of the Bcr‐Abl T315I mutant. In this review we will report the most interesting second‐generation Abl and dual Src/Abl inhibitors recently entered in clinical trial, but also the new ATP‐competitive and uncompetitive inhibitors published in the last few years, focusing on their chemical structure, mechanism of action, and structure–activity relationship.  © 2009 Wiley Periodicals, Inc. Med Res Rev, 31, No. 1, 1–41, 2010
The human rhinovirus: human‐pathological impact, mechanisms of antirhinoviral agents, and strategies for their discovery
Authors: Rollinger Judith M. , Schmidtke Michaela 
Published: August 2009

AbstractAs the major etiological agent of the common cold, human rhinoviruses (HRV) cause millions of lost working and school days annually. Moreover, clinical studies proved an association between harmless upper respiratory tract infections and more severe diseases e.g. sinusitis, asthma, and chronic obstructive pulmonary disease. Both the medicinal and socio‐economic impact of HRV infections and the lack of antiviral drugs substantiate the need for intensive antiviral research. A common structural feature of the approximately 100 HRV serotypes is the icosahedrally shaped capsid formed by 60 identical copies of viral capsid proteins VP1‐4. The capsid protects the single‐stranded, positive sense RNA genome of about 7,400 bases in length. Both structural as well as nonstructural proteins produced during the viral life cycle have been identified as potential targets for blocking viral replication at the step of attachment, entry, uncoating, RNA and protein synthesis by synthetic or natural compounds. Moreover, interferon and phytoceuticals were shown to protect host cells. Most of the known inhibitors of HRV replication were discovered as a result of empirical or semi‐empirical screening in cell culture. Structure–activity relationship studies are used for hit optimization and lead structure discovery. The increasing structural insight and molecular understanding of viral proteins on the one hand and the advent of innovative computer‐assisted technologies on the other hand have facilitated a rationalized access for the discovery of small chemical entities with antirhinoviral (anti‐HRV) activity. This review will (i) summarize existing structural knowledge about HRV, (ii) focus on mechanisms of anti‐HRV agents from synthetic and natural origin, and (iii) demonstrate strategies for efficient lead structure discovery. © 2009 Wiley Periodicals, Inc. Med Res Rev, 31, No. 1, 42–92, 2010
Probability or frequency? Expressing forecast uncertainty in public weather forecasts
Authors: Joslyn Susan L. , Nichols Rebecca M. 
Published: August 2009

AbstractIs uncertainty expressed as frequency easier for non‐experts to understand than uncertainty expressed as probability? The experiment reported here compared participants' responses to the same wind speed forecast expressed several different ways. Three different uncertainty expressions were tested (90%, 9 times in 10, or 90 out of 100%). Also tested was whether understanding was improved by including a short phrase explaining, in lay terms, how the forecast was derived (adding a reference class). Results suggested that, contrary to prior research, participants better understood the forecast when it was presented in a probability format rather than a frequency format. Furthermore, specifying a reference class did not facilitate understanding. Copyright © 2009 Royal Meteorological Society
Neuromuscular morphometry of the vaginal wall in women with anterior vaginal wall prolapse
Authors: Inal Hasan Ali , Kaplan Petek Balkanlı , Usta Ufuk , Taştekin Ebru , Aybatlı Aysun , Tokuc Burcu 
Published: August 2009

AbstractIntroduction and HypothesisThe aim of this study was to compare the changes in hystomorphometry and innervation of the anterior vaginal wall in women with and without anterior vaginal wall prolapse.MethodsEighty‐nine biopsy specimens were obtained from the anterior vaginal wall of women having a cystocele repaired (stage ≥II; prolapse group, 49) and the same location in patients with no prolapse (stage <II; control group, 40). Routine H&E staining and immunohistochemical staining for protein gene product 9.5 (PGP‐9.5) and smooth muscle α‐actin (SMA) were performed for all specimens.ResultsNumber and diameter of the submucosal nerve fibers were significantly lower, submucosal distance to muscular region was significantly higher in the vaginal wall of patients with cystocele than in women with normal vaginal support. We found that there was a negative correlation between the vaginal delivery and the nerve number and diameter measurements, and positive correlation between the vaginal delivery and submucosal distance of muscular level.ConclusionsResults indicate that women with a cystocele have a significantly lower total innervation and higher muscular distance of the anterior vaginal epithelium than the control subjects. Neurourol. Urodynam. 29:458–463, 2010. © 2009 Wiley‐Liss, Inc.
The effects of thermoform molding conditions on polyvinylchloride and polyethylene double layer package materials
Authors: Oksuz Mustafa , Alsac Cafer , Ates Murat 
Published: August 2009

AbstractThis work reports the effects of thermoform molding process conditions on polyvinylchloride (PVC) and polyethylene (PE) double layer package materials. Mechanical and microstructural properties of the package material were examined by different test methods which are tensile properties, tear resistances and scanning electron microscopy (SEM). Furthermore, package materials, which are produced in different conditions by thermoform molding. Effect of different mold depths and process temperatures on the samples are determined by thermal aging process at 60°C in first, third, and seventh days. With increase in mold depth from 25 mm to 75 mm, there is a significant increase in tensile strength from ∼45 MPa to ∼55 MPa, thermoform temperature at 150°C. The highest elongation of the material was obtained thermoform temperature at 165°C as 80%, mold depth at 35 mm. Tensile strength and elongation (%) of the material generally decrease by aging time with changing of mold depth (25, 35, and 75 mm) of the double layer package material. In addition, tear resistances of the material decrease via aging time in various thermoform temperatures (150°C, 165°C, and 175°C) due to the orientation of the segments. Scanning electron microscopic (SEM) images of the materials were taken for aging process in first, third, and seventh days. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Stability of ABS compounds subjected to repeated cycles of extrusion processing
Authors: Karahaliou E.‐K. , Tarantili P.A. 
Published: August 2009

AbstractIn this work, poly(acrylonitrile‐butadiene‐styrene) (ABS) was subjected to five subsequent extrusion cycles and the effect of prolonged exposure to heat and shear stresses on its structural and performance properties was investigated. More specifically, the resulting chemical changes were studied by attenuated total reflectance Fourier transform infrared spectroscopy, the thermal response was recorded on differential scanning calorimetry thermographs, whereas the thermal stability of reprocessed samples was detected with thermogravimetric analysis. Also, the rheological properties of the aforementioned compounds were investigated via melt flow index tests, to assess their processability during melt mixing and molding processes. Furthermore, the mechanical properties of the obtained composites were investigated and the observed interactions were interpreted in terms of the influence of each component on the functional properties of the final mixture. This attempt might be a contribution to recycling of ABS by means of techniques that include multiple reprocessing. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Improving the exfoliation of layered silicate in a poly(ethylene terephthalate) matrix using supercritical carbon dioxide
Authors: Samaniuk Joseph , Litchfield David , Baird Donald 
Published: August 2009

AbstractA technique for improving the exfoliation of organically modified layered silicate (OMLS) in a poly(ethylene terephthalate) (PET) matrix using super critical carbon dioxide (scCO2) is compared to traditional direct melt blending. The process relies on the rapid expansion of a scCO2/OMLS mixture directly into the second stage of a single screw extruder where the clay and scCO2 mixture is subsequently melt blended with the PET matrix. The simple, environmentally benign process results in a more highly delaminated system than traditional direct melt compounding. X‐ray diffraction analysis is used to reveal improved clay morphologies and the resulting mechanical properties are examined. Rheology is used as a tool to draw conclusions about the effect that scCO2 has on reducing PET matrix degradation during processing. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers
Study of the cellular structure heterogeneity and anisotropy of polypropylene and polypropylene nanocomposite foams
Authors: Antunes Marcelo , Velasco Jose Ignacio , Realinho Vera , Solórzano Eusebio 
Published: August 2009

AbstractThis article presents the analysis of the processing parameters influence on the foaming behavior and cellular structure of PP‐montmorillonite foams. Polypropylene nanocomposites containing 5.0 phr of an organically‐modified montmorillonite (MMT) were initially melt‐compounded in a twin‐screw extruder with azodicarbonamide (ADC) and later foamed using a one‐step compression‐molding process. The cellular structure and morphology of the foams was assessed using both scanning and transmission electron microscopies. A time‐dependant double‐effect was observed during foaming: (1) first of all, the melt strength of the polymer, too high for shorter times, not allowing full cell growth, and too low for high foaming times due to thermal oxidation; (2) and polymer degradation, clearly observed for very high foaming times, directly affecting polymer's melt resistance. Comparatively, PP‐MMT foams exhibited a broader foaming time processing window, a more isometric type of cellular structure and decreased open‐cell contents, indicating an effective nucleation and cell wall stabilization induced by the exfoliated MMT particles. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers