bluuebunny/crossref_metadata_2025_split huggingface dataset:
UV‐activated hydrosilylation: a facile approach for synthesis of hyperbranched polycarbosilanes
Authors: Zhang Guo‐Bin , Kong Jie , Fan Xiao‐Dong , Li Xin‐Gui , Tian Wei , Huang Mei‐Rong 
Published: May 2009

AbstractA facile approach for synthesis of hyperbranched polycarbosilane from AB2 monomer via UV‐activated hydrosilylation is presented in this communication. The polymerization process was monitored using real‐time FTIR spectroscopy and the resulting hyperbranched polycarbosilanes were characterized using 1H‐NMR, 13C‐NMR, 29Si‐NMR and SEC/MALLS. It is found that hyperbranched polycarbosilane can be synthesized from methyldiallylsilane via UV‐activated hydrosilylation with bis(acetylacetonato)platinum(II) as catalyst. The polymerization activated by UV irradiation was much faster than that under thermal conditions. The similar degree of branching, average number of branch units and the exponent of the Mark–Houwink equation demonstrate that the hyperbranched polycarbosilane synthesized via UV‐activated polyhydrosilylation possesses almost the same branching structure as that synthesized via thermal‐activated polyhydrosilylation. Copyright © 2009 John Wiley & Sons, Ltd.
Species‐specific communication systems in an introduced toad compared with native frogs in Australia
Authors: Hagman Mattias , Shine Richard 
Published: May 2009

Abstract
Lineage‐specific communication systems may offer innovative ways of targeting control measures at invasive species.
Recent work has identified such a scenario in invasive cane toads (Bufo marinus) in Australia: toad tadpoles flee from chemical cues derived from crushed conspecifics, and this ‘alarm pheromone’ reduces tadpole survival rates and reduces body size at metamorphosis.
Before this method can be applied in the field, however, the signal's specificity needs to be tested against a wide range of Australian frog taxa, especially tropical species sympatric with cane toads. A signal that affected native frogs as well as toads clearly would be of little use for toad control.
Laboratory studies on cane toads and nine native frog taxa from the wet–dry tropics of the Northern Territory (Cyclorana australis, C. longipes, Limnodynastes convexiusculus, Litoria caerulea, L. dahlii, L. nasuta, L. rothii, L. rubella, Opisthodon ornatus) show that toad tadpoles rarely react to chemical cues from crushed frog tadpoles, and that frog tadpoles rarely react to chemical cues from crushed toad tadpoles. Crushed toad tadpoles occasionally elicited low‐level attraction (to a potential food source) by frog tadpoles.
Overall, frog tadpoles were less responsive to chemical cues (either from crushed conspecifics or crushed toads) than were toad tadpoles. The low level of cross‐lineage reactivity is encouraging for the feasibility of using cane toad alarm pheromones to control this invasive species in Australia; the risk of collateral damage to sympatric native frogs appears to be minimal. Copyright © 2009 John Wiley & Sons, Ltd.
CTK: A new CCD Camera at the University Observatory Jena
Authors: Mugrauer M. 
Published: May 2009

AbstractThe Cassegrain‐Teleskop‐Kamera (CTK) is a new CCD imager which is operated at the University Observatory Jena since begin of 2006. This article describes the main characteristics of the new camera. The properties of the CCD detector, the CTK image quality, as well as its detection limits for all filters are presented (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An active fiber sensor for mirror vibration metrology in astronomical interferometers
Authors: Minardi S. , Chipouline A. , Krämer S. , Pertsch T. , Follert R. , Stecklum B. , Neuhäuser R. 
Published: May 2009

AbstractWe present a fiber sensor based on an active integrated component which could be effectively used to measure the longitudinal vibration modes of telescope mirrors in an interferometric array. We demonstrate the possibility to measure vibrations with frequencies up to ⋍100 Hz with a precision better than 10 nm (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Engineering of a matched pair of xylose reductase and xylitol dehydrogenase for xylose fermentation by Saccharomyces cerevisiae
Authors: Krahulec Stefan , Klimacek Mario , Nidetzky Bernd 
Published: May 2009

AbstractMetabolic engineering of Saccharomyces cerevisiae for xylose fermentation has often relied on insertion of a heterologous pathway consisting of nicotinamide adenine dinucleotide (phosphate) NAD(P)H‐dependent xylose reductase (XR) and NAD+‐dependent xylitol dehydrogenase (XDH). Low ethanol yield, formation of xylitol and other fermentation by‐products are seen for many of the S. cerevisiae strains constructed in this way. This has been ascribed to incomplete coenzyme recycling in the steps catalyzed by XR and XDH. Despite various protein‐engineering efforts to alter the coenzyme specificity of XR and XDH individually, a pair of enzymes displaying matched utilization of NAD(H) and NADP(H) was not previously reported. We have introduced multiple site‐directed mutations in the coenzyme‐binding pocket of Galactocandida mastotermitis XDH to enable activity with NADP+, which is lacking in the wild‐type enzyme. We describe four enzyme variants showing activity for xylitol oxidation by NADP+ and NAD+. One of the XDH variants utilized NADP+ about 4 times more efficiently than NAD+. This is close to the preference for NADPH compared with NADH in mutants of Candida tenuis XR. Compared to an S. cerevisiae‐reference strain expressing the genes for the wild‐type enzymes, the strains comprising the gene encoding the mutated XDH in combination a matched XR mutant gene showed up to 50% decreased glycerol yield without increase in ethanol during xylose fermentation.
Influence of pH on the expression of a recombinant epoxide hydrolase in Aspergillus niger
Authors: Naundorf Andreas , Melzer Guido , Archelas Alain , Furstoss Roland , Wohlgemuth Roland 
Published: May 2009

AbstractThe filamentous fungus Aspergillus niger was investigated in relation to its ability to produce a soluble epoxide hydrolase (EH) (E.C. 3.3.2.3) belonging to the microsomal EH family. This EH is a highly useful biocatalyst for kinetic resolution of racemic epoxides to give enantiopure building blocks. The production of EH on an industrial scale is still a major challenge and is linked to various optimization processes. In this work, production of protein and organic acids as a function of pH and cultivation time was investigated. The production of EH was highest (1000 U/L for p‐nitrostyrene oxide) under acidic fermentation conditions (pH value of about 3). The metabolic flux toward production of organic acids and thereby acidification of the environment increased with an increasing pH value. At pH 7, nearly 50% of total carbon of the substrate was incorporated into organic acids, mainly gluconic and oxalic acid. Finally, the addition of protease inhibitors, antioxidants and cryoprotectants was investigated in relation to the stability of the EH during the downstream process. The determination of the pH dependence during fermentation and understanding of the parameters influencing the stability of the enzyme has allowed us to optimize intracellular expression. The EH has been easily isolated from the biomass with high activity (1.67 U/mg lyophilisate) in a robust process.
Removal of endogenous retrovirus‐like particles from CHO‐cell derived products using Q sepharose fast flow chromatography
Authors: Strauss Daniel M. , Lute Scott , Brorson Kurt , Blank Gregory S. , Chen Qi , Yang Bin 
Published: May 2009

AbstractRetrovirus‐like particles (RVLPs) that are expressed during the production of monoclonal antibodies in Chinese hamster ovary (CHO) cell cultures must be removed during product recovery. Anion exchange chromatography (AEX) performed in product flow‐through mode, a common component in the purification of monoclonal antibodies, has been shown to provide robust removal of a related retrovirus model, but it's ability to remove the actual RVLP impurities has not been directly investigated. We have determined the ability of a typical Q sepharose process to remove actual CHO RVLP impurities. Using small scale experiments with three model antibodies, we observe that this AEX process is capable of effectively removing both in‐process and spiked RVLPs from different feedstocks containing different mAb products. In addition, we show that this AEX process also achieves a similarly high degree of RVLP removal during large scale manufacturing operations. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
A Mandarin e‐learning system based on speech recognition and evaluation
Authors: Ming Yue , Bai Zongshan 
Published: May 2009

AbstractThis paper establishes a speaker‐independent pronunciation recognition and assessment system under the background of a Mandarin e‐learning system framework. The recognition part is based on Hidden Markov Models (HMM) and improved in the aspect of acoustic and tone model. Making use of the recognition and detection results and corresponding parametric scorings, the machine scoring is performed to evaluate the quality of pronunciation its correlation with expert score are discussed. Through integrating recognition and assessment system with Web 2.0, we ultimately establish an open, shared and growing‐up virtual Mandarin learning community, where all of learners, viewers, professors, without any restrictions on time and places, can express their perspective about how to advance Mandarin learning freely. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 651–659, 2011
Real‐time line tracking based on web robot vision
Authors: Yilmaz Nihat , Sagiroglu Seref 
Published: May 2009

AbstractThis study presents a real‐time line tracking application based on web robot vision. The application is implemented with the help of Web‐SUN robot platform specially designed for research and development. Real‐time images were processed with the support libraries. The processes such as monitoring, tele‐control, parameter adjustment, and remote‐reprogramming were implemented on the designed platform through standard Internet browser without any additional software. A projection‐based line tracking algorithm and conventional PID control algorithm are used in study. Line tracking experiments are performed on a test track drawn by red tape on floor which includes curves and corners in laboratory environment. In this study, our real‐time line tracking experiments was completed smoothly in 10 tours on the test track with a maximum deviation of 12 cm. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 806–813, 2011
Anwendung der Diskrete‐Elemente‐Methode zur Simulation des Verhaltens von Schüttgütern
Authors: Weiler R. , Ripp M. , Dau G. , Ripperger S. 
Published: May 2009

AbstractLeistungsfähigere Rechnersysteme haben die Diskrete‐Elemente‐Methode (DEM) zu einem attraktiven Instrument zur numerischen Simulation des Verhaltens von Schüttgütern gemacht. Mit der Wahl der Partikelform sowie des Kontaktmodells und den zugehörigen Parametern werden spezifischen Eigenschaften eines Schüttgutes berücksichtigt. Wie hier gezeigt wird, sind diese Parameter für den Realitätsgrad der Simulation von großer Bedeutung. Allerdings steigt oft mit höherem Realitätsgrad einer Simulation die Rechenzeit stark an. So findet die Anwendung der Methode u. a. ihre Begrenzung in der Zahl der Partikel, mit der ein Apparat befüllt werden kann, da diese in starkem Maß die Rechenzeit beeinflusst. Zudem ist es häufig notwendig, die Simulationsparameter anhand von experimentellen Untersuchungen zu kalibrieren. Zur Kalibrierung sollten möglichst einfach durchzuführende experimentelle Methoden zur Verfügung stehen. Eine solche Methode zur experimentellen Untersuchung und Simulation der Ausbildung eines Schüttwinkels in einem Behälter wird vorgestellt. Zudem wird gezeigt, von welchen Parametern die Rechenzeit einer Simulation im Wesentlichen abhängt.
Synovial sarcoma
Authors: Palmerini Emanuela , Staals Eric L. , Alberghini Marco , Zanella Licciana , Ferrari Cristina , Benassi Maria Serena , Picci Piero , Mercuri Mario , Bacci Gaetano , Ferrari Sefano 
Published: May 2009

AbstractBACKGROUND:The optimal treatment for synovial sarcoma remains controversial. Treatment, outcome, and prognostic factors in patients treated in a single institution were examined.METHODS:Synovial sarcoma patients who underwent surgery at the Rizzoli Institute between 1976 and 2006 were identified and analyzed.RESULTS:Characteristics of the 250 patients (128 female; 122 male) included: median age, 37 years (range, 7‐83 years); 177 (71%) with tumors in the lower extremity, 40 (16%) with tumors in the upper extremity, and 33 with tumors in the trunk (13%); primary lesion size >5 cm in 121 patients (55%); and 204 (82%) patients with localized disease and 46 (18%) with metastatic disease at the time of presentation. All patients with localized disease underwent surgery. Twenty‐four percent of patients underwent amputation. Adequate surgical margins were achieved in 88% patients. In patients with localized disease, radiotherapy was administered to 103 (50%) patients, and chemotherapy to 98 (48%). With a median follow‐up of 5.5 years (range, 1‐30 years), the 5‐year overall survival rate was 10% for patients with metastatic disease and 76% for patients with localized disease (P = .0001). The 5‐year event‐free survival was 58% in patients with localized disease. Multivariate analysis indicated that size, age, histologic subtype, and the use of radiotherapy were independent factors for event‐free survival.CONCLUSIONS:In those patients with localized disease, a good rate of cure can be achieved. Age, size, histology, and use of radiotherapy influence prognosis, whereas to the authors' knowledge, the role of adjuvant chemotherapy remains unproven. Cancer 2009. © 2009 American Cancer Society.
Ductal carcinoma in situ in African American versus Caucasian American women
Authors: Nassar Hind , Sharafaldeen Bashar , Visvanathan Kala , Visscher Daniel 
Published: May 2009

AbstractBACKGROUND:Invasive breast carcinoma has a more aggressive phenotype and a higher mortality rate in African American (AA) than in Caucasian American (CA) women. The characteristics of ductal carcinoma in situ (DCIS) in the AA population have not been extensively studied.METHODS:The authors reviewed cases of DCIS diagnosed in AA and CA patients between 1996 and 2000 at their institution. Treatment and outcome were obtained from the clinical charts and the Surveillance, Epidemiology, and End Results database. They identified 217 AA (61%) and 141 CA (39%) patients.RESULTS:AA women were significantly older at diagnosis (61 years vs 56 years, P = .001), and the size of the tumor was larger in AA patients (P = .001). The other pathological features examined were not statistically different between the 2 groups. Treatments with surgery and radiation were also similar. However, the CA patients were more likely to receive hormone therapy. Recurrence rate as DCIS or invasive carcinoma was similar in both patient groups, as was death due to disease. Time to recurrence with invasive carcinoma, however, was shorter for AA patients (32.8 ± 13 vs 58 ± 9; P = .02). Only overall survival (OS) rate was higher for CA patients (92% vs 71% at 10 years; P = .003).CONCLUSIONS:Unlike invasive carcinoma, DCIS is diagnosed at a later age in AA patients. Except for larger size, DCIS does not have a more aggressive histology in AA patients. Treatment and recurrence rate were similar in both groups, as was death due to breast cancer. OS, however, was worse in AA women. Cancer 2009; 115:3181–8. © 2009 American Cancer Society.
Insights into achieving target hemoglobin levels: Increasing the serum ferritin parameter
Authors: Bralow Scott 
Published: May 2009

AbstractEvidence suggests that higher serum ferritin levels may not be an accurate reflection of iron stores or predict a patient's response to intravenous (IV) iron. Therefore, our dialysis unit revised its IV iron and anemia management protocol, from initially holding IV iron at a lower limit of serum ferritin to now continuing IV iron therapy at higher serum ferritin levels. This article describes our facility's experiences with IV iron administration at higher serum ferritin levels and the resulting improvements in patient outcomes as measured by an improved erythropoietic response.
Zebrafish wnt3 is expressed in developing neural tissue
Authors: Clements Wilson K. , Ong Karen G. , Traver David 
Published: May 2009

AbstractWnt signaling regulates embryonic patterning and controls stem cell homeostasis, while aberrant Wnt activity is associated with disease. One Wnt family member, Wnt3, is required in mouse for specification of mesoderm, and later regulates neural patterning, apical ectodermal ridge formation, and hair growth. We have identified and performed preliminary characterization of the zebrafish wnt3 gene. wnt3 is expressed in the developing tailbud and neural tissue including the zona limitans intrathalamica (ZLI), optic tectum, midbrain‐hindbrain boundary, and dorsal hindbrain and spinal cord. Expression in these regions suggests that Wnt3 participates in processes such as forebrain compartmentalization and regulation of tectal wiring topography by retinal ganglia axons. Surprisingly, wnt3 expression is not detectable during mesoderm specification, making it unlikely that Wnt3 regulates this process in zebrafish. This lack of early expression should make it possible to study later Wnt3‐regulated patterning events, such as neural patterning, by knockdown studies in zebrafish. Developmental Dynamics 238:1768–1795, 2009. © 2009 Wiley‐Liss, Inc.
Construction of Two Discrete Molecular High‐Nuclearity Copper(II) Complexes as Heterogeneous Catalysts for Oxidative Coupling Polymerisation of 2,6‐Dimethylphenol
Authors: Wu Jie , Hou Hong‐Wei , Guo Yue‐Xin , Fan Yao‐Ting , Wang Xia 
Published: May 2009

AbstractReaction of a rigid conjugated clamp‐like multi‐pyridineligand N,N′‐bis(pyridin‐3‐yl)‐2,6‐pyridinedicarboxamide (H2L) with CuSO4·5H2O or Cu(OAc)2 resulted in the formation of two high‐nuclearity, discrete molecular copper(II) complexes, namely [Cu10(H2L)5(SO4)8(μ3‐OH)4(H2O)2]·4CH3CH2OH·7H2O (1) and [Cu6(L)4(CH3COO)4]·2DMF·6H2O (2). In 1, ten copper atoms are engaged by five H2L ligands, eight SO42– and four μ3‐OH groups to form a novel decanuclear copper complex which sits on a crystallographic twofold axis passing through the centre of the complex. The structure of 2 features a hexanuclear copper cage and a crystallographic centre of inversion is at the mid‐point of the compound. The rigid conjugated clamp‐like H2L ligands, polydentate in nature, form a “coordination pocket” arising from their “arms” to entrap the copper atoms and play an important role in the assembly of discrete molecular high‐nuclearity complexes 1 and 2. Applications of 1 and 2 as heterogeneous catalysts for the oxidative polymerisation of 2,6‐dimethylphenol showed very promising results at ambient temperature and these novel catalytic systems are very mild, efficient, regioselective and easily recyclable. The interesting catalytic properties of 1 and 2 can be attributed to their particular structural characteristics and their unusual reactivities based on cooperativity or electron transfer between multicopper centres. Magnetic studies of these copper(II) cages indicate antiferromagnetic behaviour. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Syntheses, Structure and Photoluminescence Properties of Silver(I) Complexes with Naphthalene Iminoimides
Authors: Yang Hong , Lao Yan‐Ni , Chen Jia‐Min , Wu Hui‐Xia , Yang Shi‐Ping 
Published: May 2009

AbstractThree silver(I) complexes, namely [Ag(L)(NO3)]∞ (1), [Ag(L)2(NO3)] (2) and [Ag(L)2](BF4) (3) {L = 9,10‐dihydro‐7H‐benzo[de]imidazo[2,1‐a]isoquinolin‐7‐one}, have been synthesized and characterized by X‐ray crystallography, elemental analyses and FTIR spectra. The counteranions in the AgI salts and the ligand/AgI ratio play fundamental roles in the formation of AgI complexes having different crystal structures. The AgI ions in 1 and 2 are both three‐coordinate, but they are two‐coordinate in 3. Complex 1 adopts the polymeric chain‐like structure mainly bridged by nitrate anions. These chains are assembled into 2D sheets by the π–π stacking interaction of the ligands between the adjacent chains and weak intermolecular hydrogen bonds. They are further packed into 3D networks by C–H···O hydrogen bonds. For 2 and 3, mononuclear silver(I) complexes are formed. Complex 2 is extended into an infinite zigzag chain with knots by the π–π stacking interactions of the ligands and further assembled by C–H···O interactions. However, the tetrafluoroborate anions in 3 are not coordinated but are connected by intermolecular hydrogen bonds to form an infinite molecular ladder with ligand‐supported Ag–N inner rungs. All the complexes display room‐temperature photoluminescence in the visible region, which may be assigned to ligand‐centred π–π* transitions supported by the theory calculation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Specific molecular and colloidal structures of milk fat affecting lipolysis, absorption and postprandial lipemia
Authors: Michalski Marie‐Caroline 
Published: May 2009

AbstractIn milk fat, fatty acids are located at specific positions on the triacylglycerol backbone. Thesn‐2 position contains most saturated long‐chain fatty acids, while thesn‐3 position contains short‐chain fatty acids. Moreover, these triacylglycerols are structured as milk fat globules surrounded by their native membrane containing phospholipids. This native structure can be modified by the dairy processes to generate various possible colloidal structures with milk fat. The structure of triacylglycerols and the milk fat ultrastructure can impact on fatty acid digestion and absorption, which has a potential effect on cardiovascular risk factors linked to postprandial hypertriglyceridemia. The review points out the impact of the triacylglycerol structure and the ultrastructure of milk fat on these risk factors.
Two‐dimensional prediction of time dependent, turbulent flow around a square cylinder confined in a channel
Authors: Raisee M. , Jafari A. , Babaei H. , Iacovides H. 
Published: May 2009

AbstractThis paper presents two‐dimensional and unsteady RANS computations of time dependent, periodic, turbulent flow around a square block. Two turbulence models are used: the Launder–Sharma low‐Reynolds number k–ε model and a non‐linear extension sensitive to the anisotropy of turbulence. The Reynolds number based on the free stream velocity and obstacle side is Re=2.2×104. The present numerical results have been obtained using a finite volume code that solves the governing equations in a vertical plane, located at the lateral mid‐point of the channel. The pressure field is obtained with the SIMPLE algorithm. A bounded version of the third‐order QUICK scheme is used for the convective terms. Comparisons of the numerical results with the experimental data indicate that a preliminary steady solution of the governing equations using the linear k–ε does not lead to correct flow field predictions in the wake region downstream of the square cylinder. Consequently, the time derivatives of dependent variables are included in the transport equations and are discretized using the second‐order Crank–Nicolson scheme. The unsteady computations using the linear and non‐linear k–ε models significantly improve the velocity field predictions. However, the linear k–ε shows a number of predictive deficiencies, even in unsteady flow computations, especially in the prediction of the turbulence field. The introduction of a non‐linear k–ε model brings the two‐dimensional unsteady predictions of the time‐averaged velocity and turbulence fields and also the predicted values of the global parameters such as the Strouhal number and the drag coefficient to close agreement with the data. Copyright © 2009 John Wiley & Sons, Ltd.