bluuebunny/crossref_metadata_2025_split huggingface dataset:
Linear Forms in Monic Integer Polynomials
Authors: Dubickas Artūras 
Published: August 2011

Abstract. We prove a necessary and sufficient condition on the list of nonzero integers u1…, uk, k≥2, under which a monic polynomial f∊2ℤ[x] is expressible by a linear form u1 f1 + … + ukfk in monic polynomials f1…fk ∊ ℤ[x]. This condition is independent of f. We also show that if this condition holds, then the monic polynomials f1, … fk can be chosen to be irreducible in ℤ[x].
Asymptotics and Uniqueness of Travelling Waves for Non-Monotone Delayed Systems on 2D Lattices
Authors: Yu Zhi-Xian , Mei Ming 
Published: August 2011

Abstract.We establish asymptotics and uniqueness (up to translation) of travelling waves for delayed 2D lattice equations with non-monotone birth functions. First, with the help of Ikehara’s Theorem, thea prioriasymptotic behavior of travelling wave is exactly derived. Then, based on the obtained asymptotic behavior, the uniqueness of the traveling waves is proved. These results complement earlier results in the literature.
Efficacy of estrogen plus progestin on menopausal symptoms in women with systemic lupus erythematosus: A randomized, double‐blind, controlled trial
Authors: Cravioto María‐del‐Carmen , Durand‐Carbajal Marta , Jiménez‐Santana Luisa , Lara‐Reyes Pilar , Seuc Armando H. , Sánchez‐Guerrero Jorge 
Published: September 2011

AbstractObjectiveTo define the effects of continuous sequential estrogen plus progestin therapy on menopausal symptoms in women with systemic lupus erythematosus (SLE).MethodsWe performed a randomized, double‐blind, 24‐month clinical trial involving 106 women with SLE who were in the menopausal transition or early or late postmenopause. Patients received continuous sequential estrogen plus progestin (n = 52) or placebo (n = 54). Menopausal symptoms were assessed using the Greene Climacteric Scale at 0, 1, 2, 3, 6, 9, 12, 15, 18, 21, and 24 months. A new factor analysis of the scale reduced 21 items to 5 factors. The primary outcome was improvement of menopausal symptoms throughout the followup period. Results were analyzed by the intent‐to‐treat principle.ResultsAt baseline, demographic and disease characteristics were similar in both groups. Fifteen of 21 menopausal symptoms had a prevalence of ≥50%, with a similar distribution between groups. Vasomotor factor scores decreased over time in both groups (P = 0.002), but in the estrogen plus progestin group the reduction was more pronounced than in the placebo group (1.5–2.0 versus 0.35–0.8 points on a scale of 0–6; P = 0.03). Maximum effects were observed among the most symptomatic women. Psychological, subjective–somatic, and organic–somatic factors scores also improved along time (P < 0.001), but the treatment and placebo arms improved to a similar degree. Thromboses occurred in 3 patients receiving estrogen plus progestin and in 1 patient receiving placebo.ConclusionMenopausal symptoms are highly prevalent in peri‐ and postmenopausal lupus patients. Estrogen plus progestin improved vasomotor symptoms at a clinically significant level, but not other menopausal symptoms. Given the thrombotic risks of menopausal hormone therapy, this should be used only in women with significant vasomotor symptoms.
Nanosized Anatase TiO2 Single Crystals with Tunable Exposed (001) Facets for Enhanced Energy Conversion Efficiency of Dye‐Sensitized Solar Cells
Authors: Wu Xia , Chen Zhigang , Lu Gao Qing (Max) , Wang Lianzhou 
Published: September 2011

AbstractThis paper reports the synthesis of nanosized TiO2 single crystals with different percentages of exposed (001) facets in the presence of HF solution. Various characterizations are conducted to understand the correlation between particle morphology, exposed (001) facets and photo‐conversion efficiency of the nanosized anatase TiO2 single crystals. An enhancement in dye‐sensitized solar cells (DSSCs) overall conversion efficiency is observed for the photoanode consisting of nanosized TiO2 single crystals with higher percentage of exposed (001) facets, increasing from 7.47%, 8.14% to 8.49% for the TiO2 single crystals with ca. 10%, 38%, and 80% percentage of exposed (001) facets. Experimentally confirmed by dark current potential and open‐circuit voltage decay scans, such highly exposed (001) facets are not only favorable for more dye adsorption but also effectively retard the charge recombination process in DSSCs.
Super‐Fast Switching of Twisted Nematic Liquid Crystals on 2D Single Wall Carbon Nanotube Networks
Authors: Lee Won‐Kyu , Choi Yeon Sik , Kang Young‐Gu , Sung Jinwoo , Seo Dae‐Shik , Park Cheolmin 
Published: September 2011

AbstractWe have developed a high performance liquid crystal (LC) alignment layer of ultra‐thin single wall carbon nanotubes (SWNTs) and a conjugated block copolymer nanocomposite that is solution‐processible for conventional twisted nematic (TN) LC cells. The alignment layer is based on the non‐destructive solution dispersion of nanotubes with a poly(styrene‐b‐ paraphenylene) (PS‐b‐PPP) copolymer and subsequent spin coating, followed by conventional rubbing without a post‐annealing process. Topographically grooved nanocomposite films with two dimensionally (2D) networked SWNTs embedded in a block copolymer matrix were created using a rubbing process in which bundles of SWNTs on the composite surface were effectively removed. The LCs were well aligned with a stable pre‐tilt angle of approximately 2° on our extremely transparent nanocomposite, which gave rise to superfast switching of the TN LC molecules that was approximately 3.8 ms, or four times faster than that on a commercial polyimide layer. Furthermore, the TN LCD cells containing our SWNT nanocomposite alignment layers exhibited low power operation at an effective switching voltage amplitude of approximately 1.3 V without capacitance hysteresis.
Efficient Regeneration of NADPH in a 3‐Enzyme Cascade Reaction by in situ Generation of Glucose 6‐Phosphate from Glucose and Pyrophosphate
Authors: Hartog Aloysius F. , van Herk Teunie , Wever Ron 
Published: September 2011

AbstractWe report here a promising method to regenerate NADPH (nicotinamide adenine dinucleotide phosphate) using the intermediate formation of glucose 6‐phosphate (G6P) from glucose and pyrophosphate (PPi) catalyzed by the acid phosphatase from Shigella flexneri (PhoN‐Sf). The G6P formed is used in turn by glucose 6‐phosphate dehydrogenase (G6P DH) to mediate the reduction of NADP+ to NADPH. The method was tested in a one‐pot system with three enzymes in which the NADPH generated was subsequently used by an alcohol dehydrogenase (ADH) from Lactobacillus kefir or Thermoanaerobium brockii to catalyze the enantioselective reduction of acetophenone to R‐(+)‐1‐phenylethyl alcohol or S‐(−)‐1‐phenylethyl alcohol, respectively with NADP+ as starting cofactor. We were able to synthesize 50 mL of 50 mM R‐(+)‐1‐phenylethyl alcohol in the presence of 5 mM PPi and 0.4 mM NADP+. The substoichiometric amount of PPi needed demonstrates that phosphate cycling occurs. Under optimal conditions a total turnover number for NADPH higher than 3000 was reached.
Use of Protease from Bacillus licheniformis as Promiscuous Catalyst for Organic Synthesis: Applications in CC and CN Bond Formation Reactions
Authors: López‐Iglesias María , Busto Eduardo , Gotor Vicente , Gotor‐Fernández Vicente 
Published: September 2011

AbstractCommercially available protease from Bacillus licheniformis has been used in different non‐conventional biotransformations showing remarkable activity values. The promiscuous behaviour of this enzyme used in the cross‐linked enzyme aggregates immobilized form (Alcalase‐CLEA®), has been successfully demonstrated for the first time in CC bond formation processes such as aldol, Henry and Mannich reactions. On the other hand, the Bayllis–Hillman reaction between 4‐nitrobenzaldehyde and methyl vinyl ketone occurred through unspecific catalysis. Interestingly, aza‐ Michael addition reactions of secondary amines (diethylamine, piperidine and pyrrolidine) to acrylonitrile have been also efficiently catalyzed, observing with diethylamine the most remarkable differences between the enzyme‐mediated reaction and the one in the absence of catalyst. Higher reactivities were attained with pyrrolidine demonstrating the versatility of hydrolases in organic synthesis.
Dynamic Kinetic Resolution of α‐Aminonitriles to Form Chiral α‐Amino Acids
Authors: Yasukawa Kazuyuki , Hasemi Ryuji , Asano Yasuhisa 
Published: September 2011

AbstractWe have succeeded in the enzymatic synthesis of (R)‐α‐aminobutyric acid from racemic α‐aminobutyronitrile. This has been demonstrated by the use of non‐stereoselective nitrile hydratase (NHase) from Rhodococcus opacus 71D, D‐aminopeptidase from Ochrobactrum anthropi C1‐38 and α‐amino‐ε‐caprolactam (ACL) racemase from Achromobacter obae. Racemic α‐aminobutyronitrile was completely converted in 6 h at 30 °C to (R)‐α‐aminobutyric acid whose optical purity was more than 99%. (S)‐α‐Aminobutyric acid was also synthesized from α‐aminobutyronitrile by NHase, ACL racemase and L‐amino acid amidase from Brevundimonas diminuta TPU 5720. In a similar manner, other (R)‐ or (S)‐α‐amino acids with more than 97.5% ee could be synthesized from the corresponding α‐aminonitriles. This is the first report on the dynamic kinetic resolution (DKR) of α‐aminonitriles to form chiral α‐amino acids. The key enzyme in this DKR is non‐stereoselective NHase, which had been newly screened from soil samples, and its gene cloned.
Reliable predictors of neonatal immune thrombocytopenia in pregnant women with idiopathic thrombocytopenic purpura
Authors: Koyama Shinsuke , Tomimatsu Takuji , Kanagawa Takeshi , Kumasawa Keiichi , Tsutsui Tateki , Kimura Tadashi 
Published: September 2011

AbstractOf infants born to women with idiopathic thrombocytopenic purpura (ITP), about 10–15% have transient neonatal immune thrombocytopenic purpura (NITP). Of concern is the lack of a reliable predictor for NITP. We conducted a retrospective study of all pregnancies with ITP at Osaka University Hospital over the past 16 years analyzing a total of 127 pregnancies in 88 women with ITP to assess the predictive value of various clinical factors regarding neonatal platelet count in the current pregnancy. We also reviewed the literature concerning ITP in pregnancy and NITP prediction. Neonatal platelet counts were less than 100 × 109/L in 20 of 130 neonates (15.4%), less than 50 × 109/L in 11 neonates (8.5%), and less than 20 × 109/L in three neonates (2.3%). There was a strong correlation between the first and second sibling regarding the occurrence and the severity of NITP with Spearman correlation coefficient of 0.55 (P = 0.001) at birth and 0.63 (P < 0.0001) at nadir after birth. A maternal platelet count less than 100 × 109/L at delivery showed a statistical trend for an association with the occurrence of NITP (P = 0.043). Moreover, maternal ITP refractory to splenectomy correlated with a higher risk for fetal or neonatal ICH according to the review of the literature. In conclusion, pregnant women who have had a previous offspring with NITP or who have ITP refractory to splenectomy may be at particular risk of delivering an offspring with significant NITP. Management decisions, including mode of delivery, may be altered by the degree of risk for potentially severe NITP. Am. J. Hematol., 2012. © 2011 Wiley Periodicals, Inc.
Umwandlung von Kohlendioxid mit Übergangsmetall‐Homogenkatalysatoren: eine molekulare Lösung für ein globales Problem?
Authors: Cokoja Mirza , Bruckmeier Christian , Rieger Bernhard , Herrmann Wolfgang A. , Kühn Fritz E. 
Published: September 2011

AbstractIn der Vergangenheit wurde eine Vielzahl von Methoden zur Verwendung von Kohlendioxid in der organischen Synthese entwickelt. Trotz der breiten Gesamtverfügbarkeit von CO2 auf der Erde ist sein Einsatz als Reaktant, insbesondere in der Synthesechemie, recht selten. In den letzten 35 Jahren wurde intensiv daran geforscht, kosten‐ und energieeffiziente katalytische Prozesse zu finden, um CO2 zu Carbonsäuren, Estern, Lactonen und Polymeren umzusetzen. Dieser Aufsatz fasst die bis heute vorhandenen homogenkatalytischen Routen zur Verwendung von CO2 als C1‐Kohlenstoffquelle für die Synthese industrieller Produkte sowie Feinchemikalien zusammen.
Acid–base behavior of an oligomer of 3‐amino‐1,2,4‐triazole
Authors: Lamanna Melisa E. , de la Horra Enrique , Sanabria Juan , Jacobo Silvia E. , D'Accorso Norma B. 
Published: September 2011

AbstractWe report the acid–base behavior of OATA, an oligomer synthesized from 3‐amino‐1,2,4‐triazole (ATA). We analyze the UV–vis spectroscopy at different media, and we analyze and discuss the acid–base equilibria taking into account tautomeric equilibria at different pH. The low aqueous solubility at neutral pH can be attributed to the neutral form. Indeed, OATA was synthesized in an ordinary filter paper, which can be used as a sensor for ammonia as well as endpoint indication. Using the OATA‐containing paper, ammonia concentrations in a solution as low as 5 ppm could be measured. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of ZnS nanofiller and temperature on mechanical properties of poly(methyl methacrylate)
Authors: Agarwal Sonalika , Patidar Dinesh , Saxena N.S. 
Published: September 2011

AbstractThis article deals with the study of some mechanical properties of ZnS/poly(methyl methacrylate) nanocomposites prepared by solution casting method. The obtained ZnS/PMMA nanocomposites have ZnS nanoparticles in (0, 2, 4, 6, and 8) wt % and characterized through X‐ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and Fourier transform infrared (FTIR) spectroscopy measurements. Mechanical properties of ZnS/PMMA nanocomposites have been determined at different temperatures (30°C, 50°C, 70°C, and 90°C) through their stress–strain behavior using dynamic mechanical analyzer (DMA). The properties have been found to increase upto 6 wt % of ZnS nanoparticles and then decrease for 8 wt % of ZnS nanoparticles. A theoretical model has also been employed to predict the strain softening and strain hardening of the material. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Effect of the introduction of polydimethylsiloxane on the foaming behavior of block‐copolymerized polypropylene
Authors: Wang Mingyi , Ma Jun , Chu Raymond , Park Chul B. , Nanqiao Zhou 
Published: September 2011

AbstractWe investigated the effect of polydimethylsiloxane (PDMS) on the foaming properties of block‐copolymerized polypropylene (B‐PP) by blending different contents of PDMS with B‐PP in the extrusion process using supercritical CO2 as the blowing agent. The experimental results indicate that the addition of PDMS greatly increased the expansion ratio of the foamed samples. At the same time, the cell population density of foams obtained from the blends also increased to a certain degree and provided a new perspective on improving B‐PP's foaming performance. The addition of PDMS also decreased the die pressure because of the reduced viscosity of the B‐PP/PDMS blends compared with that of the B‐PP matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Rapid monitoring of bisphenol‒A diglycidyl ether formation through byproduct estimation: A study by Fourier transform infra‐red spectroscopy
Authors: Sreenadhan Jayakumar , Guria Chandan 
Published: September 2011

AbstractFor identification and quantification of desired and undesired products during epoxy resin formation, polymerization of bisphenol‐A with the stoichiometric excess of epichlorohydrin is carried out using catalytic excess of alkali. The reaction is monitored using Fourier transform infra‐red (FT‐IR) spectroscopy technique. Major undesired products are unreacted monomers (bisphenol‐A and epichlorohydrin) and byproducts (chlorine and α‐glycol substituted diglycidal ether of bisphenol‐A), whereas the desired product is only diglycidal ether of bisphenol‐A. Molar concentrations of epichlorohydrin, bisphenol‐A, diglycidal ether of bisphenol‐A, chlorine substituted resin, and α‐glycol substituted resin in the polymerization mixture are analyzed and quantified using FT‐IR characteristic frequency bands at 925, 3448, 1344, 773, and 3641 cm−1, respectively. For optimal determination of process parameters on polymerization, effect of temperature and alkali loading on epoxy polymerization is carried to maximize the yield of diglycidal ether of bisphenol‐A with simultaneous minimizing the byproducts formation. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Brain abnormalities in a Neuroligin3 R451C knockin mouse model associated with autism
Authors: Ellegood Jacob , Lerch Jason P. , Henkelman R. Mark 
Published: September 2011

AbstractMagnetic resonance imaging (MRI) has been used quite extensively for examining morphological changes in human and animal brains. One of the many advantages to examining mouse models of human autism is that we are able to examine single gene targets, like that of Neuroligin3 R451C knockin (NL3 KI), which has been directly implicated in human autism. The NL3 KI mouse model has marked volume differences in many different structures in the brain: gray matter structures, such as the hippocampus, the striatum, and the thalamus, were all found to be smaller in the NL3 KI. Further, many white matter structures were found to be significantly smaller, such as the cerebral peduncle, corpus callosum, fornix/fimbria, and internal capsule. Fractional anisotropy measurements in these structures were also measured, and no differences were found. The volume changes in the white matter regions, therefore, are not due to a general breakdown in the microstructure of the tissue and seem to be caused by fewer axons or less mature axons. A larger radial diffusivity was also found in localized regions of the corpus callosum and cerebellum. The corpus callosal changes are particularly interesting as the thinning (or reduced volume) of the corpus callosum is a consistent finding in autism. This suggests that the NL3 KI model may be useful for examining white matter changes associated with autism. Autism Res 2011,4:368–376. © 2011 International Society for Autism Research, Wiley Periodicals, Inc.
Täuschend ähnlich – Bemerkungen zur Geschichte des Modellexperiments
Authors: Brandstetter Thomas 
Published: September 2011

AbstractDeceptively Similar. Remarks on the History of Model Experiments. The article argues for a reconsideration of what has been called ‘model experiments’ or ‘mimetic experiments’. After providing a short overview of the historical developments and the occurences of such types of experiments, three aspects pertaining to their practical functions are discussed. First, the aspect of control: Model experiments are often employed to get a grasp on phenomena that are otherwise beyond the control of human actors. Second, their aesthetic dimension: Model experiments often employ aesthetic strategies that, far from being epistemic obstacles, establish their function as models and may generate new areas of research. Third, meta‐theories: The practice of experimenting on models is often accompanied by discussions about their representativeness. Albeit triggered by problems in local contexts, this self‐reflective discourse did acquire a more general relevance with the formulation of scaling laws in the 19th century.
A novel chemiluminescence system for the determination of daidzein and its hydroxyl radical‐scavenging capacity
Authors: Cai Zhuo , Zhang Xian , Lu Deng‐Feng , Gan Jing‐Ni 
Published: September 2011

ABSTRACTA novel chemiluminescence (CL) system was established for the determinations of daidzein in pharmaceutical preparations and to assess its ability to scavenge hydroxyl radicals. It was shown that a strong CL signal generated when eosin Y was mixed with Fenton reagent was decreased significantly when daidzein was added to the reaction system due to partial scavenging of the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometric relationship with the daidzein concentration. Based on this, we developed a new method for the determination of daidzein, using a flow‐injection chemiluminescence (FI–CL) technique. Under the optimal conditions, the linear range of daidzein concentration was 8.0 × 10–8–3.0 × 10–6 mol/L (R = 0.9982), with a detection limit of 9.0 × 10–9 mol/L (S:N = 3), and the RSD was 5.8% for 1.0 × 10–6 mol/L daidzein (n = 11). This method was successfully used in the determination of daidzein in tablets and for evaluation of the hydroxyl radical‐scavenging capacity of daidzein. The possible reaction mechanism of the CL system is discussed. Copyright © 2011 John Wiley & Sons, Ltd.
The N‐domain ofEscherichia coliphosphoglycerate kinase is a novel fusion partner to express aggregation‐prone heterologous proteins
Authors: Song Jong‐Am , Lee Dae‐Sung , Park Jin‐Seung , Han Kyung‐Yeon , Lee Jeewon 
Published: September 2011

AbstractAs a fusion partner to express aggregation‐prone heterologous proteins, we investigated the efficacy ofEscherichia coliphosphoglycerate kinase (ePGK) that consists of two functional domains (N‐ and C‐domain) and reportedly has a high structural stability. When the full‐length ePGK (F‐ePGK) was used as a fusion partner, the solubility of the heterologous proteins increased, but some of them still had a large fraction of insoluble aggregates. Surprisingly, the fusion expression using the N‐domain of ePGK (N‐ePGK) made the insoluble fraction significantly reduce to less than 10% for all the heterologous fusion proteins tested. Also, we evaluated the efficacy of N‐ePGK in making the target proteins be expressed with their own native function or structure. It was found that of human ferritin light chain, bacterial arginine deiminase, human granulocyte colony stimulating factor were synthesized evidently with the self‐assembly function,L‐arginine‐degrading activity, and the correct secondary structure, respectively, through the fusion expression using N‐ePGK. These results indicate that N‐ePGK is a highly potent fusion partner that can be widely used for the synthesis of a variety of heterologous proteins inE. coli. Biotechnol. Bioeng. 2012; 109:325–335. © 2011 Wiley Periodicals, Inc.
Pilot data on telmisartan short‐term effects on glucose metabolism in the olfactory tract in Alzheimer's disease
Authors: Imabayashi Etsuko , Matsuda Hiroshi , Yoshimaru Kimiko , Kuji Ichiei , Seto Akira , Shimano Yasumasa , Ito Kimiteru , Kikuta Daisuke , Shimazu Tomokazu , Araki Nobuo 
Published: September 2011

AbstractThe possible effect of antihypertensive therapy on Alzheimer's disease (AD) has been studied, and angiotensin II receptor blockers (ARBs) have been suggested to exert an effect on cognitive decline. The purpose of this study is to clarify the functional effects of telmisartan, a long‐acting ARB, on AD brain using prospective longitudinal 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) studies. For this purpose, brain glucose metabolism of four hypertensive patients with AD was examined with FDG‐PET before and after administration of telmisartan. Studied subjects underwent three FDG‐PET studies at intervals of 12 weeks. Antihypertensive treatment except for telmisartan was started after the first FDG‐PET and continued for 24 weeks. Then 40–80 mg of telmisartan was added after the second FDG‐PET and continued for 12 weeks.Glucose metabolism was significantly decreased during the first 12 weeks without telmisartan use at an area (−10, 21, −22, x, y, z; Z = 3.56) caudal to the left rectal gyrus and the olfactory sulcus corresponding to the left olfactory tract. In contrast, the introduction of telmisartan during the following 12 weeks preserved glucose metabolism at areas (5, 19, −20, x, y, z; Z = 3.09; 6, 19, −22, x, y, z; Z = 2.88) caudal to the bilateral rectal gyri and olfactory sulci corresponding to the bilateral olfactory tracts. No areas showed decreased glucose metabolism after the introduction of telmisartan. In AD, amyloid‐β deposition is observed in the anterior olfactory nucleus (AON) of the olfactory tract. Glucose metabolism in AON may be progressively decreased and preserved by telmisartan.