bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous saccharification and fermentation of steam‐pretreated bagasse using Saccharomyces cerevisiae TMB3400 and Pichia stipitis CBS6054
Authors: Rudolf Andreas , Baudel Henrique , Zacchi Guido , Hahn‐Hägerdal Bärbel , Lidén Gunnar 
Published: September 2007

AbstractSugarcane bagasse—a residue from sugar and ethanol production from sugar cane—is a potential raw material for lignocellulosic ethanol production. This material is high in xylan content. A prerequisite for bioethanol production from bagasse is therefore that xylose is efficiently fermented to ethanol. In the current study, ethanolic fermentation of steam‐pretreated sugarcane bagasse was assessed in a simultaneous saccharification and fermentation (SSF) set‐up using either Saccharomyces cerevisiae TMB3400, a recombinant xylose utilizing yeast strain, or Pichia stipitis CBS6054, a naturally xylose utilizing yeast strain. Commercial cellulolytic enzymes were used and the content of water insoluble solids (WIS) was 5% or 7.5%. S. cerevisiae TMB3400 consumed all glucose and large fraction of the xylose in SSF. Almost complete xylose conversion could be achieved at 5% WIS and 32°C. Fermentation did not occur with P. stipitis CBS6054 at pH 5.0. However, at pH 6.0, complete glucose conversion and high xylose conversion (>70%) was obtained. Microaeration was required for P. stipitis CBS6054. This was not necessary for S. cerevisiae TMB3400. Biotechnol. Bioeng. 2008;99: 783–790. © 2007 Wiley Periodicals, Inc.
The ATP‐Binding Site of Protein Kinase CK2 Holds a Positive Electrostatic Area and Conserved Water Molecules
Authors: Battistutta Roberto , Mazzorana Marco , Cendron Laura , Bortolato Andrea , Sarno Stefania , Kazimierczuk Zygmunt , Zanotti Giuseppe , Moro Stefano , Pinna Lorenzo A. 
Published: September 2007

AbstractCK2 is a highly pleiotropic Ser/Thr protein kinase that is able to promote cell survival and enhance the tumour phenotype under specific circumstances. We have determined the crystal structure of three new complexes with tetrabromobenzimidazole derivatives that display Ki values between 0.15 and 0.30 μM. A comparative analysis of these data with those of four other inhibitors of the same family revealed the presence of some highly conserved water molecules in the ATP‐binding site. These waters reside near Lys68, in an area with a positive electrostatic potential that is able to attract and orient negatively charged ligands. The presence of this positive region and two unique bulky residues that are typical of CK2, Ile66 and Ile174, play a critical role in determining the ligand orientation and binding selectivity.
Location of the Hole and Acid Proton in Neutral Nonprotonated and Protonated Mixed (Phthalocyaninato)(porphyrinato) Yttrium Double‐Decker Complexes: Density Functional Theory Calculations
Authors: Zhang Yuexing , Cai Xue , Yao Ping , Xu Hui , Bian Yongzhong , Jiang Jianzhuang 
Published: September 2007

AbstractThe location of the hole and acid proton in neutral nonprotonated and protonated mixed (phthalocyaninato)(porphyrinato) yttrium double‐decker complexes, respectively, is studied on the basis of density functional theory (DFT) calculations on the molecular structures, molecular orbitals, atomic charges, and electronic absorption and infrared spectra of the neutral, reduced, and two possible protonated species of a mixed (phthalocyaninato)(porphyrinato) yttrium compound: [(Pc)Y(Por)], [(Pc)Y(Por)]−, [(HPc)Y(Por)], and [(Pc)Y(HPor)], respectively. When the neutral [(Pc)Y(Por)] is reduced to [(Pc)Y(Por)]−, the calculated results on the molecular structure, atomic charge, and electronic absorption and infrared spectra show that the added electron has more influence on the Pc ring than on its Por counterpart, suggesting that the location of the hole is on the Pc ring in neutral [(Pc)Y(Por)]. Nevertheless, comparison of the calculation results on the structure, orbital composition, charge distribution, and electronic absorption and infrared spectra between [(HPc)Y(Por)] and [(Pc)Y(HPor)] leads to the conclusion that the acid proton in the protonated mixed (phthalocyaninato)(porphyrinato) yttrium compound should be localized on the Por ring rather than the Pc ring, despite the localization of the hole on the Pc ring in [(Pc)Y(Por)]. This result is in line with the trend revealed by comparative studies of the X‐ray single‐crystal molecular structures between [MIII{Pc(α‐OC5H11)4}(TClPP)] and [MIIIH{Pc(α‐OC5H11)4}(TClPP)] (H2TClPP=5,10,15,20‐tetrakis(4‐chlorophenyl)porphyrin; M=Sm, Eu). The present work not only represents the first systemic DFT study on the structures and properties of mixed (phthalocyaninato)(porphyrinato) yttrium double‐decker complexes, but more importantly sheds further light on the nature of protonated bis(tetrapyrrole) rare‐earth complexes.
Chameleon Reactivity of the Allene Bond of 4‐Vinylidene‐2‐oxazolidinone: Novel Through‐Space Conjugative Nucleophilic Addition of Electron‐Rich Alkenes and Hetero‐Nucleophiles
Authors: Kimura Masanari , Horino Yoshikazu , Mori Masahiko , Tamaru Yoshinao 
Published: September 2007

AbstractThe CαCβ double bond of allene carbamates 1 serves as an electron acceptor similar to the double bond of conjugated enones by means of a through‐space interaction with the NSO2 bond; the carbamate double bond is thus subject to nucleophilic addition for a wide variety of nucleophiles, which proceeds under mild conditions by heating at 70–100 °C. Depending on the kind of nucleophiles, 1 displays three different reaction modes: 1) Typically enol ethers and allylsilanes promote 1,3‐sulfonyl migration of 1 and undergo the inverse electron demand Diels–Alder reaction with the 1‐aza‐1,3‐butadiene intermediates II thus formed to furnish bicyclic 2‐alkoxy‐5‐sulfonyltetrahydropyridines 2 and 2‐silylmethyl‐5‐sulfonyltetrahydropyridines 3, respectively, with high regio‐ and stereoselectivity and retention of configuration of the double bonds of these electron‐rich alkenes; 2) silanes (RnSiH4−n, n=1–3) and thiols deliver the hydride and the thiolate at the Cβ carbon and promote the 1,3‐sulfonyl migration, followed by protonation of the thus‐formed carbamate anion (Z)‐III to provide, for example, (Z)‐4 a and (Z)‐4 j, respectively; 3) alcohols simply add to the CαCβ double bond and provide (E)‐6. Usually, the reaction with alcohols is accompanied by the second pathway, giving rise to, for example, (Z)‐4 b in addition to (E)‐6 b. Phenol engages in the third pathway and provides (E)‐6 g exclusively. Heteroaromatics, such as furans and benzofurans follow the first pathway, however, in a different regioselectivity from enol ethers and allylsilanes, delivering the oxygen atom at the 3‐position of 5‐sulfonyltetrahydropyridines (2 g and 2 h). Indoles, on the other hand, show a dichotomy, equally enjoying the first and the third pathways and provide mixtures of (E)‐7 and (E)‐8, respectively.
Suppression of background gradients in (B0 gradient‐based) NMR diffusion experiments
Authors: Zheng Gang , Price William S. 
Published: September 2007

AbstractArtifacts arising from background gradients are very common in NMR diffusion (i.e., PGSE) experiments involving B0 gradients because of the unavoidable magnetic susceptibility differences and B0 inhomogeneity within and around the sample. This article presents the general methodology to develop PGSE sequences with background gradient suppression. Most of the available methods which can be used for the suppression of the effects of background gradients are discussed. And two newly developed methods are presented in detail: frequency analysis of spin‐dephasing, which assumes the artifacts due to background gradients come from the resonance between the spin‐dephasing caused by applied gradients and background gradients, and asymmetric bipolar stimulated‐echo‐based PGSE, which can suppress the effects of nonconstant background gradients. © 2007 Wiley Periodicals, Inc.Concepts Magn Reson Part A 30A: 261–277, 2007.
Experimental realization of electromagnetically induced transparency in liquid‐state NMR
Authors: Fernandes Louis E. , Choy Jennifer T. , Khanal Devesh R. , Cory David G. 
Published: September 2007

AbstractQuantum interference effects are physical manifestations of the laws of quantum mechanics and provide a tangible link between the microscopic quantum mechanical domain and the macroscopic world that we observe. These phenomena deviate greatly from classical expectations and can be difficult to understand without experimental demonstrations. Here, we suggest an illustrative and accessible means to observe and understand a purely quantum interference effect, electromagnetically induced transparency (EIT), by viewing it from the perspective of quantum information processing (QIP). We also show that NMR, with its accessibility and ability to create pseudo‐pure states suitable for qubit manipulation, is an ideal tool for EIT. This article provides a description of EIT in QIP terms, as well as an experimental demonstration of this effect on an NMR spectrometer. © 2007 Wiley Periodicals, Inc.Concepts Magn Reson Part A 30A: 236–245, 2007.
Progress in the treatment of acute myeloid leukemia
Authors: Ravandi Farhad , Burnett Alan K. , Agura Edward D. , Kantarjian Hagop M. 
Published: September 2007

AbstractSignificant progress in understanding the mechanisms leading to the development of acute myeloid leukemia (AML) has led to the identification of numerous molecular abnormalities that may be responsible for leukemogenesis. Over the same period, large trials have established standard regimens combining cytotoxic agents for the treatment of patients with AML. Current research is attempting to better stratify patients by identifying risk factors responsible for resistance, and to discern ways for incorporating newer agents with specific and targeted activity into our standard regimens, Herein the recent developments in the diagnosis and treatment of AML are reviewed. Cancer 2007. © 2007 American Cancer Society.
Coherent anti‐Stokes Raman Scattering Microscopy
Authors: Müller Michiel , Zumbusch Andreas 
Published: September 2007

AbstractCoherent anti‐Stokes Raman scattering (CARS) microscopy is presented as a new nonlinear optical technique. The combination of vibrational spectroscopy and microscopy allows highly sensitive investigations of unlabelled samples. CARS is an ideal tool for studying a broad variety of samples. The main drawback of the technique is its non‐zero‐background nature, which implies that the signal has to be detected against a nonresonant background. The need to solve this problem is reflected in the rapid technological developments that have been observed during the last decade. Recent results show that CARS microscopy has the potential to become an important complementary technique that can be used with other well‐established microscopic methods. Although it has some limitations, it offers unique access to many problems that cannot be tackled with conventional techniques. For this reason, it can be expected that the impressive growth of the field will continue.
Das Herkulesbauwerk in Kassel‐Wilhelmshöhe
Authors: Huster Ulrich , Seim Werner 
Published: September 2007

AbstractIm Jahr 2007 wurde mit der grundlegenden Instandsetzung des Herkulesbauwerks in Kassel‐Wilhelmshöhe begonnen. Die geplanten Baumaßnahmen, die Teil der Aufwertung und Neukonzeptionierung der Kasseler Museumslandschaft sind, wurden durch eine umfassende Recherche zur Bau‐ und Schadensgeschichte sowie durch Erkundungen des Baugefüges und materialtechnologische Untersuchungen vorbereitet. Im vorliegenden Beitrag werden die wichtigsten Ergebnisse dieser Zustandserfassung erläutert; die wichtigsten Maßnahmen der statisch‐konstruktiven Sicherung des Bauwerks werden vorgestellt.
Bestandsmodernisierung und Bestandsersatz – ein Vergleich der Nachhaltigkeit unter besonderer Berücksichtigung von “nachhaltigem Mauerwerk”
Authors: Pfeiffer Martin 
Published: September 2007

AbstractDie deutsche Gesellschaft, Politik, Wohnungs‐ und Bauwirtschaft verstärken die notwendigen Bemühungen zum nachhaltigen Umgang mit dem baulichen Bestand des Wohnungs‐ und Nichtwohnungsbaus in der Zukunft. Das Bauministerium lässt aktuell zur “Zukunft Bau” und zum “Leitbild Bauwirtschaft” intensiv forschen.
Bemessung von unbewehrtem Mauerwerk nach dem genaueren Verfahren – EC 6 und DIN 1053 im Vergleich
Authors: Jäger Wolfram 
Published: September 2007

AbstractIn dem Beitrag werden der EC 6 und die DIN 1053‐100 gegenübergestellt und verglichen. Auf bestehende Unterschiede wird aufmerksam gemacht. Differenzstandpunkte werden beleuchtet und Begründungen für diese angegeben. Es soll damit eine Basis geschaffen werden, Klärungen und Entscheidungen herbeizuführen.Mit der in Angriff genommenen Überarbeitung der DIN 1053‐1 bei gleichzeitiger Integration der Konstruktion und Ausführung soll abgesichert werden, dass ein konsensfähiger nationaler Standpunkt zum EC 6 bezogen werden kann und zugleich eine dem neuesten Stand entsprechende Norm bereitsteht, die im Bedarfsfalle der Praxis zur Verfügung gestellt werden kann.Für die Architekten, Ingenieure und Ausführenden besteht hinsichtlich der Anwendung der DIN 1053‐100 kein Grund zur Beunruhigung. Die jetzt laufenden Normungsaktivitäten haben das Ziel, rechtzeitig vorausschauend zu arbeiten und andererseits aber auch erreichbare Verbesserungen schnell weiterzureichen.
Platinum‐Catalyzed Intermolecular Hydroamination of Alkenes: Halide‐Anion‐Promoted Catalysis
Authors: Brunet Jean‐Jacques , Chu Ngoc‐Chau , Rodriguez‐Zubiri Mireia 
Published: September 2007

AbstractTetraalkylphosphonium halides play the role of “promoters” for the previously unknown PtII‐catalyzed hydroamination of alkenes. The promoting effect of these “cocatalysts” depends only upon their anionic moiety. The PtII/nBu4PBr system exhibits an unprecedented catalytic activity (aerobic conditions) for the hydroamination of ethylene and 1‐hexene (regioselectivity > 95 %, Markovnikov).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Intramolecular Hydroaminations Mediated by Reductive Mercuration or n‐Butyllithium To Afford 3‐Methyl‐ and 3,4‐Dimethyl‐1,2,3,4‐tetrahydroisoquinolines
Authors: Pathak Rakhi , Naicker Prevashni , Thompson Warren A. , Fernandes Manuel A. , de Koning Charles B. , van Otterlo Willem A. L. 
Published: September 2007

AbstractThe synthesis of 3‐methyl‐ and 3,4‐dimethyltetrahydroisoquinolines from aromatic aminoalkenes using intramolecular hydroamination reactions is described. This reaction was achieved by way of a reductive aminomercuration using mercuric acetate followed by sodium borohydride, or by using sub‐stoichiometric amounts of n‐butyllithium. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Glucose Biosensors Based on Electrodes Modified with Ferrocene Derivatives Intercalated into Mg/Al Layered Double Hydroxides
Authors: Colombari M. , Ballarin B. , Carpani I. , Guadagnini L. , Mignani A. , Scavetta E. , Tonelli D. 
Published: September 2007

AbstractTwo amperometric biosensors based on glassy carbon electrodes (GC) modified with Mg/Al layered double hydroxides (LDHs) containing ferrocene‐carboxylate (FcCO2H) or ferrocene‐sulfonate (FcSO3H), as interlayer anions, and glucose oxidase (GOx) are presented. Amperometric detection of glucose involves the electrochemical oxidation of H2O2 mediated by the ferrocene derivative. Optimization of the biosensors construction and of the operative conditions was investigated and is discussed herein. The performances of the two biosensors were evaluated by chronoamperometry, working at low anodic potentials (+0.400 V for FcCO2H and +0.500 V for FcSO3H vs. SCE). The linearity extended up to 1.5 mM and 10.0 mM in batch and in flow conditions, respectively, for both biosensors, whereas the sensitivity was higher for the one based on FcCO2H (4.8±0.3 versus 2.0±0.3 μA mM−1cm−2 in batch mode, and 63.9±0.4 versus 25.8±0.4 μA mM−1cm−2 in flow mode). The biosensors display rapid response time (less than 20 s), good reproducibility, as well as good operational stability. Glucose can be accurately determined in the presence of the most common interferences that coexist in blood serum if an oxidative membrane containing nanoparticles of MnO2 is applied on the biosensors' surface.
Voltammetric Behavior of p‐Nitrophenol and Its Trace Determination in Human Urine by Liquid Chromatography with a Dual Reductive Mode Electrochemical Detection System
Authors: Honeychurch Kevin C. , Hart John P. 
Published: September 2007

AbstractThe determination of trace p‐nitrophenol (PNP) concentrations in human urine has been successfully achieved by high performance liquid chromatography dual electrode detection (LC‐DED) in the reduction‐reduction mode. Initial cyclic voltammetric studies were undertaken to investigate the electrochemical behavior of PNP at a glassy carbon electrode over a wide pH range; the redox processes giving rise to the signals have been deduced. Further, deductions regarding the behavior in the flow cells were made from hydrodynamic voltammetric data. PNP eluting from the analytical LC column is first reduced to p‐hydroxylaminophenol, at the first generator electrochemical cell. This species then undergoes chemical oxidation to give a quinoneimine species which is then detected at the downstream detector electrode using an applied potential of −0.1 V. The optimum chromatographic mobile phase consisted of 40% acetonitrile, 60% water, containing 25 mM o‐phosphoric acid, at a flow rate of 0.5 mL/min; this was used in conjunction with a Hypersil C18 column. Hydrodynamic voltammetric studies were undertaken to investigate the dual electrode behavior of PNP, and an applied potential of −2.0 V at the generator cell and −0.10 V at the detector cell were found to be optimum. The response was found to be linear over the range 7.0 ng to 500 ng on column, with an associated R2 value of 0.9981; the limit of detection was found to be 1.0 ng PNP on column. No interferences were seen for a number of common drugs or for the principal electrochemically active components of human urine or serum. The developed assay was successfully applied to the determination of trace concentrations of PNP in human urine samples, exhibiting coefficients of variation of 7.1% (n=7), with a mean recovery of 94.7% for urine fortified at 522 ng mL−1.
Serological Diagnosis of Tularemia in Mice Using the Amperometric Immunosensor
Authors: Pohanka Miroslav , Skládal Petr 
Published: September 2007

AbstractTularemia caused by the bacterium Francisella tularensis belongs to danger infective diseases, therefore timely diagnosis is an important part of protective activities. A novel approach for serological diagnostics of tularemia using a four‐channel amperometric immunosensor was proposed and evaluated on BALB/c mice as a model organism. The immunosensor was able to work with small volumes of serum samples (0.05 μL per assay) and diagnosed tularemic infection very early after immunization. From the 5th day, it was possible to distinguish tularemic sera from control sera from mice immunized with Escherichia coli on the probability level of 0.99 (t‐test). Some 40 measurements per one hour can be realized with the developed procedure. The obtained results were confirmed by the standard indirect ELISA. The proposed immunosensor‐based approach seems promising for rapid detection of microbial pathogen infections.
Determination of caffeine in coffee products by dynamic complexation with 3,4‐dimethoxycinnamate and separation by CZE
Authors: Nogueira Thiago , do Lago Claudimir Lucio 
Published: September 2007

AbstractA method based on the formation of π‐complexes with chlorogenate‐like species was proposed for the determination of caffeine in regular (nondecaffeinated) and decaffeinated coffee. Both caffeate and 3,4‐dimethoxycinnamate were able to transform caffeine – a neutral species in aqueous solutions – into an anionic species. The usage of 3,4‐dimethoxycinnamate in the running electrolyte is advantageous, because of its greater chemical stability and the improved resolution of the peaks of caffeine, theobromine, and theophylline. Negative peaks were registered with a capacitively coupled contactless conductivity detector when solutions of these alkylxanthines were analyzed with a BGE composed of 20 mmol/L 3,4‐dimethoxycinnamic acid and pH adjusted to 8.5 with Tris. This behavior was expected, because the complex is larger and thus should move slower than the free anion. Caffeine was determined in ground and instant coffee with precision and accuracy that meet Brazilian norms about such products. The LOD was estimated as 33 mg/L, which corresponds to 0.8 and 0.3 mg of caffeine per gram of dry instant coffee and ground coffee, respectively. For the case of decaffeinated coffee, ten times preconcentration with dichloromethane was carried out to allow the quantitation of caffeine, which should not exceed the concentration of 1 mg/g in dry matter.
Epigenetic aspects of genotoxic and non‐genotoxic hepatocarcinogenesis: Studies in rodents
Authors: Pogribny Igor P. , Rusyn Ivan , Beland Frederick A. 
Published: September 2007

AbstractHepatocellular carcinoma, which is one of the most prevalent life‐threatening human cancers, is showing an increased incidence worldwide. Recent evidence indicates that the development of hepatocellular carcinoma is associated with not only genetic alterations, but also with profound epigenetic changes. This review summarizes the current knowledge about epigenetic alterations during rodent hepatocarcinogenesis, considers the similarities and differences in epigenetic effects of genotoxic and non‐genotoxic rodent liver carcinogens, and discusses the possible role of these effects in the causality of liver tumor development. Environ. Mol. Mutagen., 2008. Published 2007 Wiley‐Liss, Inc.
Influence of heat and moisture exchanger respiratory load on transcutaneous oxygenation in laryngectomized individuals: A randomized crossover study
Authors: Zuur J. Karel , Muller Sara H. , Sinaasappel Michiel , Hart Guus A. M. , van Zandwijk Nico , Hilgers Frans J. M. 
Published: September 2007

AbstractBackgroundHigh‐resistance heat and moisture exchangers (HMEs) have been reported to increase transcutaneous oxygenation (tcpO2) values in laryngectomized individuals and to negatively influence patient compliance. The goal of the present study was to validate earlier published results on short‐term transcutaneous oxygenation changes by high‐resistance HMEs.MethodsWe conducted a randomized crossover study, monitoring the influence of an HME on tcpO2 over a 2‐hour time interval in 20 subjects.ResultsNo evidence of an immediate HME effect (95% CI: −14.9–13.3 mm Hg, p = .91), or a time‐dependent HME effect (95% CI: −.121 – .172 mm Hg/minute, p = .74), on tcpO2 was found. After fitting the statistical model without time dependency, again no evidence of HME presence was seen (95% CI: −.5 mm Hg – 3.6 mm Hg, p = .15).ConclusionIn contrast to earlier suggestions, there is no evidence of increased tcpO2 levels by high‐resistance HMEs in laryngectomized individuals. Thus, using such HMEs has no added clinical value in this respect. © 2007 Wiley Periodicals, Inc. Head Neck, 2007