bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acute silent cerebral infarction in children with sickle cell anemia
Authors: Dowling Michael M. , Quinn Charles T. , Rogers Zora R. , Buchanan George R. 
Published: October 2009

AbstractSilent cerebral infarctions (SCI) occur in up to 35% of children with sickle cell anemia (HbSS) but are rarely recognized during the initial 10–14 days when diffusion weighted magnetic resonance imaging (MRI) can differentiate acute infarctions from remote events. We report acute SCI in seven children with HbSS who had areas of restricted diffusion on MRI without persistent focal neurologic deficits. Four had acute SCI identified following acute anemic events. Our observations suggest that SCI are detectible in the acute phase, present with subtle neurologic symptoms, result in permanent neurologic injury, and may be caused by acute anemic events. Pediatr Blood Cancer 2010;54:461–464. © 2009 Wiley‐Liss, Inc.
Friction and wear properties of PTFE composites filled with PA6
Authors: Li J. 
Published: October 2009

AbstractBlending Polytetrafluoroethylene (PTFE) to PA6 at different compositions was produced in a corotating twin‐screw extruder, where PTFE acts as the polymer matrix and PA6 as the dispersed phase. The effects of PA6 content on the tribological properties of the composites were investigated. The worn surface morphologies of neat PTFE and its composites were examined by scanning electron microscopy (SEM), and the wear mechanisms were discussed. The presence of PA6 particles dispersed in the PTFE continuous phase exhibited superior tribological characteristics to unfilled PTFE. The optimum wear reduction was obtained when the content of PA6 is 30 vol%. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Influence of core fillers on resin flow and fiber compaction of cocured skin‐to‐stiffener structures
Authors: Wang Xueming , Xie Fuyuan , Li Min , Zhang Zuoguang 
Published: October 2009

AbstractThe integral molding technology is the development of composite structures. In this study, an experimental integral technology of cocuring was applied to fabricate T‐stiffened skins. A study was undertaken to determine the effect of fillers in stiffener core on resin flow and fiber compaction of T‐stiffened skins. A new application of transferring pressure film was carried out to measure the pressure distribution in T‐stiffeners. The characteristics of resin flow were investigated by the bleeding quantity and the stiffener thickness in prebleeding process. The experimental results indicated that nonuniform pressure obviously distributed in T‐stiffeners, especially the lowest pressure exhibited in stiffener corner. Resin‐rich defect and highest thickness were frequently obtained in stiffener corner. However, rolling unidirectional prepregs as fillers into the stiffener core of T‐stiffened skins caused an increase of pressure in stiffener corner, gave the stiffener corner to the opportunity to remove the resin‐rich defect by hindering resin flow into the stiffener corner, and consequently contributed to a significant increase in the fiber compaction and manufacturing quality of T‐stiffeners. POLYM. COMPOS., 31:1360–1368, 2010. © 2009 Society of Plastics Engineers
Characteristics of embryo development in Robertsonian translocations' preimplantation genetic diagnosis cycles
Authors: Huang Jin , Lian Ying , Qiao Jie , Chen Yongjian , Ren Xiulian , Liu Ping 
Published: October 2009

AbstractObjectiveTo explore the embryo development characteristics in Robertsonian translocations (RTs) in their preimplantation genetic diagnosis (PGD) cycles.MethodA total of 37 RT carrier couples underwent 41 blastomere PGD cycles from August 2005 to September 2008. The development of 272 embryos was analyzed in their PGD cycles.Result(s)At D3, there were 161 high‐grade embryos, including 59 normal/balanced embryos and 102 abnormal embryos. There was no difference between the normal/balanced embryo group and the abnormal embryo group in terms of the high‐grade embryo percentage (64.84% vs 56.35%, p = 0.179). However, at D5–D6, the blastocyst percentage in the normal/balanced embryo group was significantly higher than that in the abnormal embryo group (43.96% vs 20.44%, p = 0.000).Conclusion(s)Normal/balanced embryos developed better and a self‐selective mechanism may exist in the RTs' embryos at the blastocyst formation stage. Copyright © 2009 John Wiley & Sons, Ltd.
Study on the applicability of frontomaxillary facial angle in the first‐trimester trisomy 21 fetuses in Chinese population
Authors: Chen Min , Yang Xin , Leung Tak Yeung , Sahota Daljit Singh , Fung Tak Yuen , Chan Lin Wai , Lao Terence Tzu‐Hsi , Lau Tze Kin 
Published: October 2009

AbstractObjectiveTo evaluate the measurement of frontomaxillary facial (FMF) angle at 11 weeks to 13 weeks, 6 days in a Chinese population and its applicability in the screening for fetal trisomy 21.MethodIn a retrospective study, the stored images for the measurement of fetal nuchal translucency (NT) thickness in a Chinese population from August 2003 to March 2007 were reviewed for the comparison of the FMF angle between 22 trisomy 21 fetuses (study group) with 220 randomly selected normal fetuses with satisfactory images (control group).ResultsNo association between FMF angle and NT, nasal bone length, or fetal heart rate was shown (P > 0.05). But the FMF angle was significantly greater in the trisomy 21 fetuses (89.7 vs 82.8, P < 0.001). The intraobserver and interobserver agreement were assessed in 9.5% (n = 21) normal cases. Mean (SD) differences of two observers were −0.83 (2.69)° (P > 0.05). For each observer, mean (SD) differences between the two paired measurements were −0.98 (3.11)° and 0.93 (1.80)°, respectively (P > 0.05).ConclusionOur results indicated that measurement of the FMF angle in the first trimester can be incorporated into the screening of trisomy 21 in the Chinese population, and its application is not affected by intraobserver and interobserver variability. Copyright © 2009 John Wiley & Sons, Ltd.
Atomic force microscopy: A powerful molecular toolkit in nanoproteomics
Authors: Dufrêne Yves F. 
Published: October 2009

AbstractAnalysing microbial cell surface proteins is a challenging task in current microbial proteomic research, which has major implications for drug design, vaccine development, and microbial monitoring. In this context, atomic force microscopy (AFM) has recently emerged has a powerful characterization platform, providing valuable insights into the surface proteome of microbial cells. The aim of this article is to show how advanced AFM techniques, that all have in common functionalization of the AFM tip with specific molecules, can be used to answer pertinent questions related to surface‐associated proteins, such as what is their spatial arrangement on the cell surface, and what are the forces driving their interaction with the environment?
The Shigella dysenteriae serotype 1 proteome, profiled in the host intestinal environment, reveals major metabolic modifications and increased expression of invasive proteins
Authors: Pieper Rembert , Zhang Quanshun , Parmar Prashanth P. , Huang Shih‐Ting , Clark David J. , Alami Hamid , Donohue‐Rolfe Arthur , Fleischmann Robert D. , Peterson Scott N. , Tzipori Saul 
Published: October 2009

AbstractShigella dysenteriae serotype 1 (SD1) causes the most severe form of epidemic bacillary dysentery. We present the first comprehensive proteome analysis of this pathogen, profiling proteins from bacteria cultured in vitro and bacterial isolates from the large bowel of infected gnotobiotic piglets (in vivo). Overall, 1061 distinct gene products were identified. Differential display analysis revealed that SD1 cells switched to an anaerobic energy metabolism in vivo. High in vivo abundances of amino acid decarboxylases (GadB and AdiA) which enhance pH homeostasis in the cytoplasm and protein disaggregation chaperones (HdeA, HdeB and ClpB) were indicative of a coordinated bacterial survival response to acid stress. Several type III secretion system effectors were increased in abundance in vivo, including OspF, IpaC and IpaD. These proteins are implicated in invasion of colonocytes and subversion of the host immune response in S. flexneri. These observations likely reflect an adaptive response of SD1 to the hostile host environment. Seven proteins, among them the type III secretion system effectors OspC2 and IpaB, were detected as antigens in Western blots using piglet antisera. The outer membrane protein OmpA, the heat shock protein HtpG and OspC2 represent novel SD1 subunit vaccine candidates and drug targets.
Living copolymerization of ethylene with norbornene mediated by heteroligated (Salicylaldiminato)(β‐enaminoketonato)titanium catalysts
Authors: Long Ying‐Yun , Ye Wei‐Ping , SHI XIN‐CUI , Li Yue‐Sheng 
Published: October 2009

AbstractThree heteroligated (salicylaldiminato)(β‐enaminoketonato)titanium complexes [3‐But‐2‐OC6H3CHN(C6F5)][(p‐XC6H4)NC(But)CHC(CF3)O]TiCl2 (3a: X = F, 3b: X = Cl, 3c: X = Br) were synthesized and investigated as the catalysts for ethylene polymerization and ethylene/norbornene copolymerization. In the presence of modified methylaluminoxane as a cocatalyst, these unsymmetric catalysts exhibited high activities toward ethylene polymerization, similar to their parallel parent catalysts. Furthermore, they also displayed favorable ability to efficiently incorporate norbornene into the polymer chains and produce high molecular weight copolymers under the mild conditions, though the copolymerization of ethylene with norbornene leads to relatively lower activities. The sterically open structure of the β‐enaminoketonato ligand is responsible for the high norbornene incorporation. The norbornene concentration in the polymerization medium had a profound influence on the molecular weight distribution of the resulting copolymer. When the norbornene concentration in the feed is higher than 0.4 mol/L, the heteroligated catalysts mediated the living copolymerization of ethylene with norbornene to form narrow molecular weight distribution copolymers (Mw/Mn < 1.20), which suggested that chain termination or transfer reaction could be efficiently suppressed via the addition of norbornene into the reaction medium. Polymer yields, catalytic activity, molecular weight, and norbornene incorporation can be controlled within a wide range by the variation of the reaction parameters such as comonomer content in the feed, reaction time, and temperature. ©2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6072–6082, 2009
Mechanism of cyclic dye regeneration during eosin‐sensitized photoinitiation in the presence of polymerization inhibitors
Authors: Avens Heather J. , Bowman Christopher N. 
Published: October 2009

AbstractA visible light photoinitiator, eosin, in combination with a tertiary amine coinitiator is found to initiate polymerization despite the presence of at least 1000‐fold excess dissolved oxygen, which functions as an inhibitor of radical polymerizations. Additionally, 0.4 μM eosin is able to overcome 100‐fold excess (40 μM) 2,2,6,6‐Tetramethyl‐1‐piperidinyloxy (TEMPO) inhibitor, initiating polymerization after only a 2 min inhibition period. In contrast, 40 μM Irgacure‐2959, a standard cleavage‐type initiator, is unable to overcome even an equivalent amount of inhibitor (40 μM TEMPO). Through additional comparisons of these two initiation systems, a reaction mechanism is developed which is consistent with the kinetic data and provides an explanation for eosin's relative insensitivity to oxygen, TEMPO, and other inhibitors. A cyclic mechanism is proposed in which semireduced eosin radicals react by disproportionation with radical inhibitors and radical intermediates in the inhibition process to regenerate eosin and effectively consume inhibitor. In behavior similar to that of eosin, rose bengal, fluorescein, and riboflavin are also found to initiate polymerization despite the presence of excess TEMPO, indicating that cyclic regeneration likely enhances the photoinitiation kinetics of many dye photosensitizers. Selection of such dye initiation systems constitutes a valuable strategy for alleviating inhibitory effects in radical polymerizations. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6083–6094, 2009
Aminated PCL‐based copolymers by chemical modification of poly(α‐iodo‐ε‐caprolactone‐co‐ε‐caprolactone)
Authors: El Habnouni Sarah , Blanquer Sébastien , Darcos Vincent , Coudane Jean 
Published: October 2009

AbstractA novel method is proposed to access to new poly(α‐amino‐ε‐caprolactone‐co‐ε‐caprolactone) using poly(α‐iodo‐ε‐caprolactone‐co‐ε‐caprolactone) as polymeric substrate. First, ring‐opening (co)polymerizations of α‐iodo‐ε‐caprolactone (αIεCL) with ε‐caprolactone (εCL) are performed using tin 2‐ethylhexanoate (Sn(Oct)2) as catalyst. (Co)polymers are fully characterized by 1H NMR, 13C NMR, FTIR, SEC, DSC, and TGA. Then, these iodinated polyesters are used as polymeric substrates to access to poly(α‐amino‐ε‐caprolactone‐co‐ε‐caprolactone) by two different strategies. The first one is the reaction of poly(αIεCL‐co‐εCL) with ammonia, the second one is the reduction of poly(αN3εCL‐co‐εCL) by hydrogenolysis. This poly(α‐amino‐ε‐caprolactone‐co‐ε‐caprolactone) (FαNH2εCL < 0.1) opens the way to new cationic and water‐soluble PCL‐based degradable polyesters. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6104–6115, 2009
Synthesis and characterization of poly(fluorinated vinyl ether‐alt‐tert‐butyl α‐trifluoromethacrylate) copolymers
Authors: Cracowski Jean‐Marc , Montembault Véronique , Odobel Fabrice , Améduri Bruno , Fontaine Laurent 
Published: October 2009

AbstractRadical copolymerizations of electron acceptor tert‐butyl α‐trifluoromethacrylate (MAF‐TBE) and electron donor 1,1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8‐heptadecafluoro‐10‐(vinyloxy)decane (FAV8) initiated by tert‐butyl 2,2‐dimethylperoxypropanoate were investigated. Although none of both monomers underwent radical homopolymerization under classical conditions, they readily copolymerized, producing a soluble copolymer containing 60–65 mol % of MAF‐TBE. The reactivity ratios determined by the Kelen‐Tüdos method were found to be rMAF‐TBE = 0.03 ± 0.01 and rFAV8 = 0 at 74 °C, indicating the synthesis of alternated copolymers. The copolymer compositions were assessed from 19F‐NMR spectroscopy and correlated with thermogravimetric analysis. Molecular weights and polydispersity indexes of poly(MAF‐TBE‐alt‐FAV8) copolymers were both low and ranged from 5.5 to 6.9 × 103 g mol−1 and from 1.08 to 1.23, respectively. Copolymers were amorphous, and Tg were about 55 °C for all copolymers. TGA analyses showed the release of isobutene from MAF‐TBE units in copolymers before a degradation of the resulting poly(α‐trifluoromethacrylic acid‐alt‐FAV8) copolymers, occurring at 250–260 °C. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6116–6123, 2009
Immobilization of flame retardant onto silica nanoparticle surface and properties of epoxy resin filled with the flame retardant‐immobilized silica
Authors: Yamauchi Takeshi , Yuuki Akira , Wei Gang , Shirai Kumi , Fujiki Kazuhiro , Tsubokawa Norio 
Published: October 2009

AbstractTo prepare silica nanoparticle having flame retardant activity, the immobilization of flame retardant onto hyperbranched poly(amidoamine) (PAMAM)‐grafted silica was investigated. Grafting of PAMAM onto a silica surface was achieved in a solvent‐free dry‐system using PAMAM dendrimer synthesis methodology. The immobilization of bromine flame retardant, poly(2,2′,6,6′‐tetrabromobisphenol‐A) diglycidyl ether (PTBBA), was successfully achieved by the reaction of terminal amino groups of PAMAM‐grafted silica (Silica‐PAMAM) with epoxy groups of PTBBA. The immobilization of PTBBA was confirmed by FTIR and thermal decomposition GC‐MS. The amount of PTBBA immobilized onto Silica‐PAMAM was determined to be 60 wt %. PTBBA‐immobilized Silica‐PAMAM (Silica‐PAMAM‐PTBBA) was dispersed uniformly in a epoxy resin, and the epoxy resin was cured in the presence of hexamethylenediamine. Flame retardant activity of the epoxy resin filled with Silica‐PAMAM‐PTBBA was estimated by limiting oxygen index (LOI). The LOI of epoxy resin filled with Silica‐PAMAM‐PTBBA was higher than that filled with untreated silica and free PTBBA. It was confirmed that the flame retardant activity of epoxy resin was improved by the addition of the Silica‐PAMAM‐PTBBA. The elimination of PTBBA from the epoxy resin filled with Silica‐PAMAM‐PTBBA into boiling water was hardly observed by immobilization of PTBBA onto silica surface. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6145–6152, 2009
Acute toxicity of Schizolobium parahyba aqueous extract in mice
Authors: Mendes Mirian M. , Vale Luis H. F. , Lucena Malson N. , Vieira Sâmela A. P. B. , Izidoro Luiz Fernando M. , Junior Robson J. O. , Soares Andreimar M. , Alcântara Tânia M. , Hamaguchi Amélia , Homsi‐Brandeburgo Maria Inês , Rodrigues Veridiana M. 
Published: October 2009

AbstractThe herbal extract of Schizolobium parahyba leaves is used commonly in the Brazil central region to treat snakebites. This study evaluates the acute toxicological effects of Schizolobium parahyba aqueous extract in mice 24 h after intraperitoneal administration. Acute toxicity was evaluated using biochemical, hematological and histopathological assays. Alterations in the levels of transaminases, bilirubin, albumin and prothrombrin time were observed, and these are likely to occur due to hepatic injury, which was confirmed by light microscopy. Liver histopathological analysis revealed the presence of lymph plasmocitary inflammatory infiltrate, but no other histopathological alterations were observed in any of the other organs analysed. The data confirm the low toxicity of the extract of Schizolobium parahyba and provide a model for the selection of a dose that does not cause injuries in the organism. Copyright © 2009 John Wiley & Sons, Ltd.
Ethanol extract of Fructus Ligustri Lucidi promotes osteogenesis of mesenchymal stem cells
Authors: Li Guo , Zhang Xiao‐ai , Zhang Jin‐fang , Chan Chu‐yan , Yew David Tai Wai , He Ming‐liang , Lin Marie Chia‐mi , Leung Ping‐chung , Kung Hsiang‐fu 
Published: October 2009

AbstractFructus Ligustri Lucidi (FLL) has been used in traditional Chinese medicine for over 1000 years. The ethanol extract of FLL (EFLL) has been shown to be a potential candidate in the prevention and treatment of osteoporosis. The present study aimed to determine whether EFLL carries out the effect by promoting osteogenesis in mesenchymal stem cells (MSCs). The osteogenic differentiation of MSCs was evaluated by their alkaline phosphatase (ALP) activities and mineralization. Expression of genes was detected by RT‐PCR. We found that EFLL significantly stimulated the ALP activities and shortened the time needed for the mineralization of MSCs during osteogenic differentiation. The expression of several osteoblast differentiation regulators was also upregulated by EFLL during this process. Our study demonstrated that the EFLL is capable of enhancing osteogenic differentiation of MSCs. It might be useful for treating diseases with inadequate bone formation, including osteoporosis. Copyright © 2009 John Wiley & Sons, Ltd.
Combination of Ant Colony Optimization with Various Local Search Strategies. A Novel Method for Variable Selection in Multivariate Calibration and QSPR Study
Authors: Shamsipur Mojtaba , Zare‐Shahabadi Vali , Hemmateenejad Bahram , Akhond Morteza 
Published: October 2009

AbstractRecently, we applied successfully ant colony optimization (ACO) to wavelength selection problem. In this paper ant colony system (ACS), a version of ACO algorithms, has been applied to variable selection in multivariate calibration and QSPR studies. In addition, the effect of combination of ACS algorithm with various local search strategies was inspected. The suggested local search strategies included forward selection, backward elimination, forward selection together with backward elimination, backward elimination together with forward selection, genetic algorithm, and tabu search. Parameters of ACS and combined local search strategy were optimized. The results obtained from all ACS algorithms indicated that combination of various local search strategies to the ACS algorithm improved the performance of the ACS algorithm.
Academic preparation in biology and advocacy for teaching evolution: Biology versus non‐biology teachers
Authors: Nehm Ross H. , Kim Sun Young , Sheppard Keith 
Published: October 2009

AbstractDespite considerable focus on evolution knowledge–belief relationships, little research has targeted populations with strong content backgrounds, such as undergraduate degrees in biology. This study (1) measured precertified biology and non‐biology teachers' (n = 167) knowledge of evolution and the nature of science; (2) quantified teacher preferences for the teaching of creationism in schools; (3) examined the associations among knowledge and belief variables; and (4) contrasted the knowledge and beliefs of prospective biology teachers with those of non‐biology teachers. Methodologically, teacher knowledge was quantified by using three measures and studied in relation to certification area, self‐reported religiosity, personal conflict concerning science and religion, and completion of an evolution course. We found (1) generally low levels of knowledge of evolution and the nature of science—and high misconception magnitudes—in both biology and non‐biology teachers; (2) comparable antievolutionary positions in biology and non‐biology teachers: nearly half of the teachers in both groups advocated for the inclusion of creationism in school; (3) weak association between knowledge and preference/belief variables; and (4) no difference in preference for teaching creationism between those teachers who had taken an evolution course and those who had not. Overall, biology and non‐biology teachers were found to display “mixed” and “novice naturalistic” evolutionary reasoning patterns. © 2009 Wiley Periodicals, Inc. Sci Ed 93:1122–1146, 2009
Beginning elementary teachers' beliefs about the use of anchoring questions in science: A longitudinal study
Authors: Forbes Cory T. , Davis Elizabeth A. 
Published: October 2009

AbstractCurrent science education reform efforts highlight the importance of engaging students in scientifically oriented questions as a central dimension of inquiry‐based elementary science. However, elementary teachers, particularly beginning teachers, must often overcome a variety of challenges to engage their students in reform‐minded, standards‐based, inquiry‐oriented classroom practice. To better support beginning elementary teachers' learning to support students to ask and answer scientifically oriented questions, it is necessary to better understand their beliefs about questions and questioning, as well as how they negotiate these beliefs at this crucial stage of the teacher professional continuum. Four beginning elementary teachers were studied longitudinally over their first 3 years of professional teaching careers. Results show that each teacher cited the importance of driving questions and investigation questions to establish purpose and promote student sense‐making. However, they followed different trajectories in reconciling their ideas about the use of driving questions and investigation questions in light of the particular facets of science teaching they prioritized. These findings have important implications for current perspectives on teacher learning along the teacher professional continuum and help inform research on teachers and teaching, as well as teacher education and science curriculum development. © 2009 Wiley Periodicals, Inc. Sci Ed 94:365–387, 2010