bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel UBE3A mutations causing Angelman syndrome: Different parental origin for single nucleotide changes and multiple nucleotide deletions or insertions
Authors: Camprubí Cristina , Guitart Miriam , Gabau Elisabeth , Coll Maria Dolors , Villatoro Sergi , Oltra Silvestre , Roselló Monica , Ferrer Irene , Monfort Sandra , Orellana Carmen , Martínez Francisco 
Published: February 2009

AbstractAngelman syndrome (AS) is a genetic disorder caused by a deficiency of UBE3A imprinted gene expression from the maternal chromosome 15. In 10% of AS cases the genetic cause is a mutation affecting the maternal copy of the UBE3A gene. In two large Spanish series of clinically stringently selected and nonstringently selected patients, we have identified 11 pathological mutations—eight of them novel mutations—and 14 sequence changes considered polymorphic variants. Remarkably, single nucleotide substitutions are more likely to be inherited, while multiple nucleotide deletions or insertions are less frequently inherited, thus indicating that single nucleotide substitutions are more likely to originate from the paternal germline. Additionally, there seems to be a different distribution of nucleotide changes and multiple nucleotide deletions or insertions along the UBE3A gene sequence. © 2009 Wiley‐Liss, Inc.
Juvenile macular dystrophy and forearm pronation‐supination restriction presenting with features of distal arthrogryposis type 5
Authors: Castori Marco , Rinaldi Rosanna , Barboni Luana , Tanzilli Paolo , Bamshad Michael , Grammatico Paola 
Published: February 2009

AbstractThe distal arthrogryposes are a heterogeneous group of conditions characterized by congenital contractures of hands and feet, and autosomal dominant inheritance. The concurrence of ophthalmoplegia and additional ocular findings distinguish distal arthrogryposis type 5 (DA5). This rare subtype has been described in 33 patients to date and its clinical spectrum of physical findings is still poorly understood. We report on a family with three individuals with DA5. The index case came to our attention because of restricted forearm pronation‐supination and juvenile macular dystrophy. Further examination revealed short stature, firm muscles, stiff spine with lumbar hyperlordosis, generalized mild limitation of the large joints, external rotation of the hips, unilateral ptosis, exophoria, and abnormal photopic and scotopic responses on electroretinogram testing. However, there was no overt evidence of contractures of the distal joints. Examination of other affected family members revealed restricted range of movement of the small joints together with ulnar deviation of the fingers, and clarified the diagnosis. Our observations suggest that DA5 may have a very mild musculoskeletal phenotype and it should be considered in the differential of congenital contracture syndromes even in the absence of obvious distal joint involvement. Our observations also suggest that fundoscopy and ocular electrophysiological studies might be helpful in the evaluation of patients with otherwise unclassified distal arthrogryposes. Am. J. Med. Genet. © 2009 Wiley‐Liss, Inc.
Molecular breakpoint mapping of 6q11‐q14 interstitial deletions in seven patients
Authors: Wang Jia‐Chi , Dang Linda , Lomax Brenda , Turner Lesley , Shago Mary , Teebi Ahmad S. , Klatt Regan , MacLeod Patrick M. , Yong Siu‐Li , Nowaczyk Malgorzata J.M. , Eydoux Patrice 
Published: February 2009

AbstractInterstitial deletions involving 6q11‐q14 have been reported in less than 20 patients, with the breakpoints studied by G‐banding alone. We report on seven patients with 6q11‐q14 interstitial deletions of variable size. The breakpoints were studied by G‐banding, dual‐color BAC‐FISH and SNP array. The results showed the molecular breakpoints differed significantly from the ones obtained from G‐banding. The breakpoints studied by BAC‐FISH were consistent with the ones from SNP array. Some characteristics from this cohort are consistent with previous reports, but many typical features are lacking in our patients. The cardinal features of 6q11‐q14 interstitial deletions in this cohort include: umbilical hernia, hypotonia, short stature, characteristic facial features of upslanting palpebral fissures, low set and/or dysplastic ears, high arched palate, urinary tract anomalies, and skeletal/limb anomalies. © 2009 Wiley‐Liss, Inc.
Nickel‐Catalyzed Borylative Coupling of Alkynes, Enones, and Bis(pinacolato)diboron as a Route to Substituted Alkenyl Boronates
Authors: Mannathan Subramaniyan , Jeganmohan Masilamani , Cheng Chien‐Hong 
Published: February 2009

AbstractDreikomponentenkupplungen mit einem Alkin, einem Enon und einem Diborreagens eröffnen den Zugang zu hoch substituierten Alkenylboronaten in guten bis hervorragenden Ausbeuten (siehe Schema). Die Kupplung verläuft hoch regio‐ und stereoselektiv, und die Produkte lassen sich anschließend noch weiter modifizieren. R1,R2=H, Alkyl, Aryl, CO2Me; R3=Alkyl, Ph; R4,R5=H, Alkyl.magnified image
Raman‐spektroskopische Studie der Phasenumwandlung von amorpher in kristalline β‐Kohlensäure
Authors: Kohl Ingrid , Winkel Katrin , Bauer Marion , Liedl Klaus R. , Loerting Thomas , Mayer Erwin 
Published: February 2009

AbstractHilfreiche Labordaten für die Detektion von Kohlensäure auf der Oberfläche der Mars‐Polkappen, wenn 2009 das Mars‐Microbeam‐Raman‐Spektrometer wie geplant auf dem Mars landet, bieten die hier vorgestellten Raman‐Spektren von Kohlensäure (H2CO3), und zwar sowohl vom β‐Polymorph als auch vom amorphen Zustand. Der Bildhintergrund zeigt einen Marskrater mit Eis unbekannter Zusammensetzung, in dem möglicherweise Kohlensäure existiert (Überarbeitung eines Bildes der deutschen Marskamera, mit Erlaubnis von ESA, DLR und FU Berlin – G. Neukum).magnified image
Spider Silk: From Soluble Protein to Extraordinary Fiber
Authors: Heim Markus , Keerl David , Scheibel Thomas 
Published: February 2009

AbstractOn a silky thread: Spider silks have mechanical properties that outperform most natural and synthetic fibers. Classical spinning methods have failed to mimic the highly complex natural in‐vivo spinning process. Analyzing this process in combination with in‐vitro findings allows the development of biomimetic spinning devices for the technical production of silk fibers (see picture).magnified imageSpider silks outrival natural and many synthetic fibers in terms of their material characteristics. In nature, the formation of a solid fiber from soluble spider silk proteins is the result of complex biochemical and physical processes that take place within specialized spinning organs. Herein, we present natural and artificial silk production processes, from gene transcription to silk protein processing and finally fiber assembly. In‐vivo and in‐vitro findings in the field of spider silk research are the basis for the design of new proteins and processing strategies, which will enable applications of these fascinating protein‐based materials in technical and medical sciences.
Coordination Polymers: From Metal–Organic Frameworks to Spheres
Authors: Champness Neil R. 
Published: February 2009

AbstractSphere of destiny: Metal–organic spheres with remarkable encapsulation properties are readily prepared and their ability to host a wide range of guest species, including nanoparticles, fluorescent dyes, and quantum dots, is demonstrated. Both the metal–organic spheres and the encapsulated species maintain their fluorescent or magnetic properties, highlighting the importance of these systems as new multifunctional materials.magnified image
Wear of the artificial hip joint material under lubrication
Authors: Waters E. P. J. , Spedding P. L. , Doherty A.P. , Spedding R. L. 
Published: February 2009

AbstractA study of wear properties of hip‐replacement materials, namely high‐nitrogen stainless‐steel femoral heads and ultra‐high molecular weight polyethylene (UHMWPE), was conducted in a non‐conforming apparatus using various liquid lubricants. The liquids used were normal saline solution, sodium azide solution, pure ethanol, aqueous hyaluronic acid and aqueous hyaluronic acid/cholesterol and cholesterol palmitate liquid crystal lubricant. Saline solution proved to be unsuitable as a lubricant while sodium azide that was used as a bactericide provided some evidence of mixed lubrication. A bactericide was included to overcome degradation. The aqueous hyaluronic acid exhibited cushion form lubrication as evidenced by retention of the original polymer surface features within the wear indent. Cholesterol addition showed little improvement on the wear properties but massively increased the bacterial activity. Again, inclusion of a bactericide was necessary. Liquid crystal lubricant significantly reduced wear and the atomic force microscope (AFM) showed that the liquid crystal formed protective layers on the counter face surfaces. The sub‐surface of the polymer possessed plastic creep under load but low adhesive wear was present. There also was an absence of sub‐micron polymer debris. It was concluded that a dramatic reduction in wear could be achieved by incorporation of liquid crystal lubricant in hip‐replacement elements. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
New type of phenolic resin: Curing reaction of phenol‐novolac based benzoxazine with bisoxazoline or epoxy resin using latent curing agent and the properties of the cured resin
Authors: Kimura Hajime , Matsumoto Akihiro , Ohtsuka Keiko 
Published: February 2009

AbstractIn this study, we aimed to reduce the cure time, and to lower the cure temperature of the benzoxazine compound. Therefore, curing reaction of benzoxazine with bisoxazoline or epoxy resin using the latent curing agent and the properties of the cured resins were investigated. The cure behavior of benzoxazine with bisoxazoline or epoxy resin using the latent curing agent was monitored by differential scanning calorimetry and measurements for storage modulus (G′). The properties of the cured resin were estimated by mechanical properties, electrical insulation, water resistance, heat resistance, and flame resistance. As a result, it was confirmed that by using the latent curing agent, cure time of benzoxazine and bisoxazoline or epoxy resin was reduced, and cure temperature was lowered. And it was found that the curing reaction using phenol‐novolac based benzoxazine (Na) as the benzoxazine compound could proceed more rapidly than that using bisphenol‐A based benzoxazine (Ba) as the benzoxazine compound. However, the cured resins from Ba and bisoxazoline or epoxy resin using the latent curing agent showed good heat resistance, flame resistance, and mechanical properties compared with those from Na and bisoxazoline or epoxy resin using the latent curing agent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effects of functionalized MWNTs with GMA on the properties of PMMA nanocomposites
Authors: Zheng Yaping , Zhang Jiaoxia , Xiaodong Yang , Chen Weiwei , Wang Rumin 
Published: February 2009

AbstractThe acid modification of multiwall carbon nanotubes (MWNTs) was performed by an HNO3/H2SO4 solution. The glycidyl methacrylate (GMA) undergoing an opening‐ring was grafted onto the surface of acid‐modified MWNTs. The surface properties of MWNTs were investigated by Fourier transform infrared spectrometer (FTIR), Raman spectra, transmission electron microscopy (TEM), X‐ray diffraction, and thermogravimeric analysis. Then the MWNTs/ poly(methyl methacrylate) (PMMA) nanocomposites were prepared by in situ polymerization. The tribological and dielectric properties of nanocomposites were studied. As a result, GMA was grafted on the surface of MWNTs. The tribological and dielectric properties of MWNTs/ PMMA nanocomposites were improved as the content of the surface‐modified MWNT increased. The marked improvement in tribological and dielectric properties were attributed to the good dispersion of MWNTs that were bonded with CC on the surface that participated in the polymerization of MMA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Enzymatic degradation of hyperbranched polyesters
Authors: Mallepally Rajendar Reddy , Smirnova Irina , Arlt Wolfgang , Seiler Matthias , Klee‐Laquai Saskia K. , Hills Geoffrey 
Published: February 2009

AbstractIn this work, the enzyme‐catalyzed degradation of hyperbranched polyesters (HBPEs) was investigated. Enzymatic degradation experiments were performed in a phosphate buffer in the presence of the lipases Candida cylindracea, Pseudomonas cepacia, Novozym 388, Amano CE, Lipomod 34P, and Cal‐B, whereas control experiments were performed in the same system without lipases. The extent of polymer degradation was determined by quantification of the released free fatty acids by gas chromatography. The influence of the alkane chain length and the number of alkane chain end groups on the lipase‐catalyzed hydrolysis of esterified HBPEs was investigated systematically. It was found that the increase in the alkane chain length of the end groups diminished the enzymatic degradation of the polymer, whereas the number of end groups had no influence on the degradation rate. The effect of temperature on the rate of degradation was also described. Surface morphological changes that occurred during the degradation were assessed with reflected electron microscopy. The changes in the crystallinity of the polymers after they were subjected to degradation were qualitatively determined with differential scanning calorimetry through the quantification of the enthalpy of melting. The enthalpy of melting of one HBPE sample increased from 79 to 90 and 94 J/g with and without the action of Lipomod 34P, respectively, in 7 days, showing the changes in the crystallinity of the polymer. The results prove that modified HBPEs are an important new class of biodegradable materials with a predictable degradation mechanism, and the degradation can be adjusted on the basis of the molecular engineering. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
PVDF/PMMA composite nanofiber fabricated by electrospray deposition: Crystallization of PVDF induced by solvent extraction of PMMA component
Authors: Danno T. , Matsumoto H. , Nasir M. , Minagawa M. , Horibe H. , Tanioka A. 
Published: February 2009

AbstractThe crystallization of poly(vinylidene fluoride) (PVDF) was observed after the poly(methyl methacrylate) (PMMA) component was extracted from the PVDF/PMMA (50/50) composite nanofiber fabricated by electrospray deposition, even though the original composite showed a completely amorphous pattern in the wide‐angle X‐ray diffraction. The content of the β‐crystal form in the crystalline region depended on the PVDF/PMMA composite ratios and the type of solvents used for the extraction of the PMMA component, e.g., chloroform and toluene. Thus, the content of the β‐crystal form can be controlled by selecting the original PVDF/PMMA composition and the solvent used to extract the PMMA component. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Mechanical, vulcametric, and thermal properties of the different 5‐ethylidene 2‐norbornene content of ethylene‐propylene‐diene‐monomer vulcanized with different types and compositions of peroxides
Authors: Çavdar Seda , Özdemir Tonguç , Usanmaz Ali 
Published: February 2009

AbstractEthylene‐propylene‐diene‐monomer (EPDM) rubber is an important commercial polymer. The vulcanization process significantly changes its thermal, mechanical, and vulcametric properties. This study was carried out to find optimum formulation of EPDM composite for a better application in automotive industry. Sixteen EPDM polymer samples having different 5‐ethylidene 2‐norbornene (ENB) and ethylene contents were vulcanized with different types and compositions of peroxide and coagents. The mechanical and vulcametric properties of these samples were measured and compared. The type of peroxide, coagent, and EPDM grade affected the mechanical, thermal, and vulcametric properties of the EPDM rubber to some extend. Use of aromatic peroxide and coagent increased the thermal stability slightly. Mechanical properties were changed very slightly with the change of peroxide type for the same content of peroxide and coagent. Scorch time and cure time decreased with initial increase of the peroxide content. EPDM compound vulcanized with BBPIB peroxide and TAC/S coagent has higher cure time than EPDM compound vulcanized with DMBPHa peroxide and TMPTMA coagent. Coran method was used for the modeling of experimental data. Velocity constant for the formation of peroxide radical and polymer radical were found for each case. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of prepolymerization on propylene polymerization
Authors: Monji Majid , Abedi Sadegh , Pourmahdian Saeed , Taromi Faramarz Afshar 
Published: February 2009

AbstractPolymerization of propylene was performed using MgCl2. EtOH.TiCl4.ID.TEA.ED catalyst system in hexane, where internal donor (ID) was an organic diester and external donor (ED) was a silane compound and also triethyl aluminum (TEA) as activator. A new method called isothermal/nonisothermal method (INM), a combination of isothermal and nonisothermal methods, was applied to produce the spherical polymer particles. The effects of the INM method and prepolymerization temperature on the final polymer morphology, Mw, and catalyst activity were also investigated. The morphology of the polymers was evaluated through scanning electron microscopy (SEM) images. GPC results were used for molecular weight (Mw) evaluation. It was found that the polymers had a better morphology when they were prepared using INM method. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of LCP and rPET as reinforcing materials on rheology, morphology, and thermal properties of in situ microfibrillar‐reinforced elastomer composites
Authors: Saikrasun Sunan , Limpisawasdi Panpirada , Amornsakchai Taweechai 
Published: February 2009

AbstractMicrofibrillar‐reinforced elastomer composites based on two dispersed phases, liquid crystalline polymer (LCP) and recycled poly(ethylene terephthalate)(rPET), and styrene‐(ethylene butylene)‐styrene (SEBS) were prepared using extrusion process. The rheological behavior, morphology, and thermal stability of SEBS/LCP and SEBS/rPET blends containing various dispersed phase contents were investigated. All blends and LCP exhibited shear thinning behavior, whereas Newtonian fluid behavior was observed for rPET. The incorporation of both LCP and rPET into SEBS significantly improved the processability by bringing down the melt viscosity of the blend system. The fibrillation of LCP dispersed phase was clearly observed in as‐extruded strand with addition of LCP up to 20–30 wt %. Although the viscosity ratio of SEBS/rPET system is very low (0.03), rPET domains mostly appeared as droplets in as‐extruded strand. The results obtained from thermogravimetric analysis suggested that an addition of LCP and rPET into the elastomer matrix improved the thermal resistance significantly in air but not in nitrogen. The simultaneous DSC profiles revealed that the thermal degradation of all polymers examined were endothermic and exothermic in nitrogen and in air, respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The design of a test protocol to model the degradation of polyolefins during recycling and service life
Authors: Strömberg Emma , Karlsson Sigbritt 
Published: February 2009

AbstractIn terms of the sustainable development for polymeric materials the recovery of plastic waste by means of mechanical recycling is a favorable technique. The largest part of the collected plastic municipal solid waste fraction consists of packaging materials, e.g., polypropylene (PP) and polyethylene. A major drawback to the increased use of recycled polymers is the lack of knowledge about the property changes and the overall quality of the recyclates, e.g., the degree of degradation, mixing, and contamination. This article presents a test protocol for description of the mechanical, physical, and chemical property changes during recycling and service life by combining several reprocessing cycles and thermo‐oxidation. The test protocol was designed to mimic the degradation mechanisms potentially occurring in the materials during the service life and the reprocessing. Virgin PP and HDPE were multiply processed by injection molding. Service life of plastic materials was modeled by accelerated thermal degradation of one time processed materials. Tensile testing, MFR, HT‐SEC, DSC, FTIR, and SEM were used to analyze material changes. In parallel, a set of industrially recycled PP and HDPE were also subjected to the same analyses. The results proved that recycled plastics maintain the majority of the material properties even when reprocessed several times. It was demonstrated that the mechanical and thermal properties of PP and HDPE were preserved also after several reprocessing steps. Initiation of degradation was observed for PP but not for HDPE. A decrease in Mw of PP from 240,000 to 190,000 (six times reprocessed) was established, this corresponds to an increase in MFR from 8 to 18 g/10 min. By FTIR, it was shown that the carbonyl index increased. The loss of stabilizers affects the properties of the final product. In comparison, industrially recycled PP and HDPE presented to some extent poorer mechanical properties than the materials subjected to model recycling. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of plasma‐polymerized 3‐quinolinecarbonitrile and its photo(electro)‐luminescence properties
Authors: Zhao Xiong‐Yan 
Published: February 2009

AbstractA novel plasma‐polymerized 3‐quinolinecarbonitrile (PP3QCN) thin film was prepared by plasma polymerization of 3‐quinolinecarbonitrile (3QCN) for the first time. The PP3QCN thin films show a blue emission with a narrow peak at ∼ 475 nm and there appeared a relatively high intensity of PL peak. The EL devices with PP3QCN as electroluminescent layer sandwiched between ITO and Al were fabricated. It was found that the ITO/PP3QCN/Al devices also show a blue emission and PP3QCN thin film was stable and appropriate for the electroluminescent layer. The external quantum efficiency of ITO/PP3QCN/Al devices can reach to 0.0068%. The plasma‐polymerized conjugated polynitrile thin film obtained from 3QCN precursor might be a promising material for application in LED and photodiode device. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009