bluuebunny/crossref_metadata_2025_split huggingface dataset:
Layer‐by‐layer Assembled Multilayers of Graphene/Mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin for Detection of Dopamine
Authors: Tan Lin , Wang Guo , Chen Nali , Zhang Jianqiang , Feng Huixia 
Published: February 2015

AbstractGraphene/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin multilayer films composed of graphene sheet (GS) and mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (NH2‐β‐CD) were fabricated easily by two steps. First, negatively charged graphene oxide (GO) and positively charged mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (NH2‐β‐CD) were layer‐by‐layer (LBL) self‐assembled on glassy carbon electrode (GCE) modified with a layer of poly(diallyldimethylammonium chloride) (PDDA). Then graphene/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (GS/NH2‐β‐CD) multilayer films were built up by electrochemical reduction of graphene oxide/mono‐(6‐amino‐6‐deoxy)‐β‐cyclodextrin (GO/NH2‐β‐CD). Combining the high surface area of GS and the active recognition sites on β‐cyclodextrin (β‐CD), the GS/NH2‐β‐CD multilayer films show excellent electrochemical sensing performance for the detection of DA with an extraordinary broad linear range from 2.53 to 980.05 µmol·L−1. This study offers a simple route to the controllable formation of graphene‐based electrochemical sensor for the detection of DA.
Synthesis of Pyrene‐based Planar Conjugated Polymers and the Regioisomers by Intramolecular Cyclization
Authors: Zhu Xiaoyan , Wu Yonggang , Zhou Lina , Wang Yuan , Zhao Hongchi , Gao Baoxiang , Ba Xinwu 
Published: February 2015

AbstractSeveral planar conjugated polymers and model compounds containing pyrene units are synthesized. The precursor polymers and model compounds are obtained through the Pd(0)‐catalyzed Suzuki reaction, then the planar structure is formed through intramolecular cyclization in the presence of acid. We investigate the regioisomers in intramolecular cyclization reaction by using model compounds, suggesting that the syn‐ and anti‐structures are formed in ladder‐type polymer LP1, and the syn‐structure is more easily formed in LP3. The planar conjugated polymers and model compounds show untypical features of ladder‐type polymers, they display broad absorption and blue or blue‐green emission in solution, and interchain π‐π stacking in film still occurs. Moreover, the new polymers and model compounds are characterized by nuclear magnetic resonance (NMR) spectroscopy, gel‐permeation chromatography (GPC) and cyclic voltammetry (CV).
Optically Active Helical Poly[(S)‐3‐vinyl‐2,2′‐dihydroxy‐1,1′‐binaphthyl]: New Ligand for Asymmetric Addition of Diethylzinc to Aryl Aldehyde
Authors: Chen Yehui , Qin Guochang , Yang Liwen , Yang Nianfa 
Published: February 2015

AbstractPoly[(S)‐3‐vinyl‐2,2′‐dihydroxy‐1,1′‐binaphthyl] (L*) was obtained by taking off the protecting groups of poly[(S)‐3‐vinyl‐2,2′‐bis(methoxymethoxy)‐1,1′‐binaphthyl] (poly‐1). L* was proved to keep a stable helical conformation in solution. The application of helical L* in the asymmetric addition of diethylzinc to aldehydes has been studied. The catalytic system employing 10 mol% of L* and 150 mol% of Ti(OiPr)4 was found to promote the addition of diethylzinc to a wide range of aromatic aldehydes, giving up to 99% enantiomeric excess (ee) and up to 93% yield of the corresponding secondary alcohol at 0°C. The chiral polymer can be easily recovered and reused without loss of catalytic activity as well as enantioselectivity.
One‐Pot Synthesis of Aliphatic Nitro Compounds by Michael/retro‐Claisen Fragmentation Domino Reaction
Authors: Zhang Wei , Wang Yanjing , Bai Cuibing , Wen Jialong , Wang Naixing 
Published: February 2015

AbstractA novel and concise method for the construction of γ‐nitro ketones and 1,3‐dinitro compounds with chemoselective acyl transfer has been presented under basic conditions via one‐pot reactions. These reactions feature high atom‐ and step‐economic possess, mild condition and simple operation for one‐pot synthesis of aliphatic nitro compounds. This protocol provides the products in good yields. The possible reaction mechanism has also been proposed.
Intermixed Adatom and Surface‐Bound Adsorbates in Regular Self‐Assembled Monolayers of Racemic 2‐Butanethiol on Au(111)
Authors: Ouyang Runhai , Yan Jiawei , Jensen Palle S. , Ascic Erhad , Gan Shiyu , Tanner David , Mao Bingwei , Niu Li , Zhang Jingdong , Tang Chunguang , Hush Noel S. , Reimers Jeffrey R. , Ulstrup Jens 
Published: February 2015

AbstractIn situ scanning tunneling microscopy combined with density functional theory molecular dynamics simulations reveal a complex structure for the self‐assembled monolayer (SAM) of racemic 2‐butanethiol on Au(111) in aqueous solution. Six adsorbate molecules occupy a (10×√3)R30° cell organized as two RSAuSR adatom‐bound motifs plus two RS species bound directly to face‐centered‐cubic and hexagonally close‐packed sites. This is the first time that these competing head‐group arrangements have been observed in the same ordered SAM. Such unusual packing is favored as it facilitates SAMs with anomalously high coverage (30 %), much larger than that for enantiomerically resolved 2‐butanethiol or secondary‐branched butanethiol (25 %) and near that for linear‐chain 1‐butanethiol (33 %).
Developmental regulation of neural map formation in the mouse olfactory system
Authors: Nishizumi Hirofumi , Sakano Hitoshi 
Published: February 2015

ABSTRACTIn the mouse olfactory system, various odorants are detected by approximately 1000 different odorant receptors (ORs) expressed in the olfactory sensory neurons (OSNs). It is well established that each OSN expresses only one functional OR gene in a monoallelic manner. Furthermore, OSN axons expressing the same OR converge to a set of glomeruli in the olfactory bulb (OB). During embryonic development, a coarse map is formed by the combination of two genetically programmed processes. One is OR‐independent axonal projection along the dorsal‐ventral (D‐V) axis, and the other is OR‐dependent projection along the anterior‐posterior (A‐P) axis. D‐V projection is regulated by the anatomical location of OSNs within the olfactory epithelium (OE), whereas A‐P projection is instructed by expressed OR molecules using cyclic adenosine monophosphate (cAMP) signals. After birth, the map is further refined in an activity‐dependent manner by its conversion from a continuous to a discrete map through segregation of glomerular structures. Here, we summarize recent progress from our laboratory in understanding neural map formation in the mouse olfactory system. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 594–607, 2015
Antioxidant activity and phytochemical content of cold‐pressed rapeseed oil obtained from roasted seeds
Authors: Siger Aleksander , Kaczmarek Aleksandra , Rudzińska Magdalena 
Published: February 2015

An analytic comparison was made of cold‐pressed rapeseed oil produced from unroasted seeds and cold‐pressed oil produced from seeds that had previously undergone roasting at temperatures of 140, 160, and 180°C for 5, 10, and 15 min. It was determined whether the duration and temperature of roasting have any qualitative and quantitative effects on the contents of the native antioxidants (tocopherol, PC‐8, phenolic compounds, canolol, and phytosterols) found in rapeseed oil. At the same time, changes in the antioxidant activity of oils produced from roasted seeds were determined. It was shown that roasting has no significant effect on the quality of cold‐pressed oils. The peroxide value of the oils ranged from 2.03 to 3.48 meq O2/kg, while the acid value did not exceed 0.68 mg KOH/g. Slight changes were observed in oils in terms of tocochromanol contents. A decrease was seen mostly in the level of the α‐T homologue, with an increase in the contents of γ‐T and PC‐8 (in oil from seeds roasted at 180°C). In the oil from the unroasted seeds, the canolol content was 11.54 μg/g oil. It was shown that increases both in temperature and in duration of seed roasting result in a statistically significant increase in the canolol content of cold‐pressed oils. For the seed roasted at 180°C for 15 min, this increase was fifty‐fold (609.94 μg canolol/g oil). The same roasting conditions also led to a twofold increase in the antioxidant activity of the oil.Practical applications: Cold‐pressed oils are increasingly frequently chosen by consumers due to their reputation as good source of bioactive components. An obvious example of such a food product is cold‐pressed rapeseed oil made from roasted seeds, in which the levels of canolol—a product of the decarboxylation of sinapic acid—is markedly increased. This compound is ascribed strong antioxidant properties, as well as antimutagenic and anticarcinogenic properties. Such oils truly deserve to be labeled bioactive products.An analytic comparison was made of cold‐pressed rapeseed oil produced from unroasted seeds and cold‐pressed oil produced from seeds that had previously undergone roasting at temperatures of 140, 160, and 180°C for 5, 10, and 15 min. It was determined whether the duration and temperature of roasting have any qualitative and quantitative effects on the contents of the native antioxidants (tocopherol, PC‐8, phenolic compounds, canolol, and phytosterols) found in rapeseed oil. In the oil from the unroasted seeds, the canolol content was 11.54 μg/g oil. It was shown that increases both in temperature and in duration of seed roasting result in a statistically significant increase in the canolol content of cold‐pressed oils. For the seed roasted at 180°C for 15 min, this increase was fiftyfold (609.94 μg canolol/g oil). The same roasting conditions also led to a twofold increase in the antioxidant activity of the oil.
Modulation of bitterness and pungency in virgin olive oil from unripe “Picual” fruits
Authors: Aguilera Maria P. , Jimenez Antonio , Sanchez‐Villasclaras Sebastián , Uceda Marino , Beltran Gabriel 
Published: February 2015

Singular virgin olive oils (VOOs) come from unripe olives that show different characteristics affecting processing and oil sensory properties. This work is aimed to study the effect of olive paste malaxation conditions on phenolic fraction and intensities of bitter and pungent sensations in VOOs from unripe “Picual” olives. Experiments were carried out using “Picual” fruits harvested at early dates for three consecutive crop seasons. The malaxation conditions assayed using a factorial design were: time (60 and 90 min), temperature (18, 30, and 40°C) and micronized talc addition (0 and 1%). The main factors affecting oil phenol content were the crop year, malaxation temperatures, and micronized talc addition whereas for malaxation time the effect was not significant. The high olive fruit moistures had a great importance in the oil phenol content and the related sensory parameters. Results indicated as for higher temperature the phenol content and bitterness K225 increased although its effect varied by crop year. Micronized natural talc addition increased the total phenol content and the K225 values. When intensities of pungency and bitterness of the oils were ranked by sensory analysis those obtained at lower temperature were classified as less bitter and pungent. Therefore for early harvesting dates the kneading conditions can be regulated to obtain VOOs with different sensory characteristics and phenol content.Practical applications: Effect of paste malaxation conditions on the virgin olive oil (VOO) bitterness, pungency, and phenolics has been studied for early harvested “Picual” fruit. Bitterness and pungency in “Picual” VOO could be modulated by regulating the malaxation temperature achieving the lower intensities at 18°C without micronized talc addition.Temperature was the olive paste malaxation variable with the highest effect on phenol content in virgin olive oil from early harvested “Picual” fruits. Lower temperature reduced oil phenol content and then, its bitterness and pungent intensities.
A Near‐Infrared Fluorescence Probe for Thiols Based on Analyte‐Specific Cleavage of Carbamate and Its Application in Bioimaging
Authors: Zhang Jianjian , Yu Bianfei , Ning Lulu , Zhu Xinyue , Wang Jianxi , Chen Zhenjie , Liu Xiaoyan , Yao Xiaojun , Zhang Xiaoyu , Zhang Haixia 
Published: February 2015

AbstractWith increasing interest in optical in vivo imaging, there is a corresponding increase in demand for near‐infrared (NIR) dyes. Such probes can be used, for example, to detect intracellular GSH, which would be helpful for understanding the mechanisms of diseases. In this work, we report a cyanine‐based fluorescent probe that undergoes biothiol‐promoted specific O–S cleavage and subsequent self‐immolation through intramolecular 1,6‐elimination. In addition, we investigated the cell viability of the system and successfully applied the probe to living cells, in vivo, and in various tissues.
One‐Step Synthesis of Dicarboxamides through Pd‐Catalysed Aminocarbonylation with Diamines as N‐Nucleophiles
Authors: Carrilho Rui M. B. , Almeida Ana R. , Kiss Mercédesz , Kollár László , Skoda‐Földes Rita , Dąbrowski Janusz M. , Moreno Maria José S. M. , Pereira Mariette M. 
Published: February 2015

AbstractAn efficient one‐step synthetic strategy was used to prepare a set of dicarboxamides through palladium‐catalysed aminocarbonylation of iodoalkenyl and iodoaryl compounds, with use of various alkyl‐ and aryldiamines as N‐nucleophiles. The isolated yields of the dicarboxamides depended significantly on the iodo substrate and diamine structures, as well as on the reaction conditions, the best one (ca. 70 %) being achieved with 1‐iodocyclohexene as substrate and 1,4‐diaminobutane as nucleophile, at 100 °C and 30 bar of CO. When iodobenzene was used as model aryl halide, the highest yield of the target dibenzamides (ca. 65 %) was obtained with 1,4‐diaminobenzene as coupling amine, at 100 °C and 10 bar of CO. Preliminary studies on their in vitro cytotoxicity against human lung carcinoma A549 cells showed N,N′‐(butane‐1,4‐diyl)dibenzamide and androst‐16‐ene‐based dicarboxamides to be the most efficient cytotoxic agents, with IC50 values of approximately 40 μM.
Synthesis and Evaluation of Neoglycoconjugates Based on Adamantyl Scaffolds
Authors: Fleck Carsten , Memmel Elisabeth , Fölsing Moritz , Poll Bernhard , Hackl Thomas , Seibel Jürgen , Maison Wolfgang 
Published: February 2015

AbstractLectin–carbohydrate interactions are important for many biological processes of high pharmaceutical interest. Multivalent carbohydrate conjugates (glycoclusters) have been frequently used to study and manipulate these interactions. In this report, we present the synthesis of trimeric glucose and mannose conjugates that have been assembled with an AB3 scaffold based on adamantane. Several neoglycoconjugates bearing three carbohydrates have been synthesized with different ethylene glycol spacers between the sugar moieties and the adamantyl core. An additional orthogonal functionality at the remaining adamantane bridgehead position allows the conjugation of these trimeric cluster glycosides to other functional molecules such as fluorescent dyes or a solid support for the construction of glycoarrays. We have evaluated the binding properties of trivalent carbohydrate derivatives to ConA as a model lectin in solution by STD‐NMR and on a lectin array by using fluorescent glycoconjugates.
Expedient Synthesis of Homochiral 1‐Aryl‐Substituted 4,5‐Dihydro‐1H‐imidazoles and Their Modification to N‐Heterocyclic Carbene Precursors
Authors: Latham Christopher M. , Lewis William , Blake Alexander J. , Woodward Simon 
Published: February 2015

AbstractThe amidoamines (S)‐Ar1CONHCHRCH2NHAr2 [Ar1 = o‐C6H4SO3H, R = Bn, iBu, iPr; Ar2 = 2,6‐iPr2C6H4, 2,6‐Et2C6H4, 2,4,6‐Me3C6H2] cyclise to (S) 1‐aryl‐substituted 4,5‐dihydro‐1H‐imidazolinium species with HC(OEt)3 in moderate‐to‐excellent yields on heating to 150–175 °C (nine examples, four isolated yields of 48 to >97 %). They are attained as their o‐C6H4(SO3–)(CO2Et) salts. The latter are readily deprotonated to afford analytically pure (S) 1‐aryl‐substituted 4,5‐dihydro‐1H‐imidazoles (imidazolines). The purification of the intermediate sulfonate salts is not always necessary, and analytically pure imidazolines are isolated by simple kugelrohr distillation (nine examples, 45–95 %) after basification. Imidazoline alkylation provides a library of (S)‐N‐alkylimidazolinium salts (23 examples, 74–97 %). As the initially required amidoamines are available in simple one‐pot reactions, the overall approach constitutes a rather efficient approach to this useful family of chiral N‐heterocyclic carbene (NHC) ligand precursors (effectively three steps from commercial N‐Boc‐α‐amino alcohols; BOC = tert‐butyloxycarbonyl).
Furan's Gambit: Electrophile‐Attack‐Triggered Sacrifice of Furan Rings for the Intramolecular Construction of Azaheterocycles
Authors: Trushkov Igor V. , Uchuskin Maxim G. , Butin Alexander V. 
Published: February 2015

AbstractThis review summarizes the results of recent investigations of intramolecular furan ring‐opening–azaheterocycle ring‐closing reactions induced by acid or electrophilic attack on the furan ring.
Surfactant‐supplemented mixed bacterial cultures to produce hydrogen from paperboard mill wastewater
Authors: Farghaly Ahmed , Tawfik Ahmed , Eldin Ibrahim Mona Gamal 
Published: February 2015

Paperboard mill wastewater (PMW) mainly comprises complex compounds such as polysaccharides and lignin that are recalcitrant to microbial and enzymatic action. Surfactants supplementation was found to improve the enzymatic hydrolysis and reduce lignin content during anaerobic digestion process. However, much less attention has been given for the effectiveness of surfactants addition on hydrogen production from PMW under hyperthermophilic conditions. In this study, the mixed bacterial culture was supplemented with surfactants, namely PEG 6000 and Tween 80 (T80), to enhance the biodegradation process and hydrogen yield (HY). The results showed that increasing the concentration of T80 from 0.25 to 1.75% v/v significantly (p < 0.001) increased HY from 1.7 ± 0.02 to 2.6 ± 0.01 mmol/gCODinitial (where COD is chemical oxygen demand), respectively. However, with further increase in the concentration of T80 up to 2.5%, the HY dropped to 2 ± 0.04 mmol/gCODinitial. This was mainly due to a higher propionate (HPr) production. Similar trends were observed for PEG, where the maximum HY of 2.8 ± 0.02 mmol/gCODinitial was achieved at a concentration of 0.75 mg/L, which deteriorated at higher and lower concentrations of PEG. Fermentative hydrogen of 700 m3/day of PMW could support about 16.4% of total primary energy consumption of the factory.
Microstructural brain abnormalities in Huntington's disease: A two‐year follow‐up
Authors: Odish Omar F. F. , Leemans Alexander , Reijntjes Robert H.A.M. , van den Bogaard Simon J. A. , Dumas Eve M. , Wolterbeek Ron , Tax Chantal M. W. , Kuijf Hugo J. , Vincken Koen L. , van der Grond Jeroen , Roos Raymund A. C. 
Published: February 2015

AbstractObjectivesTo investigate both cross‐sectional and time‐related changes of striatal and whole‐brain microstructural properties in different stages of Huntington's disease (HD) using diffusion tensor imaging.Experimental designFrom the TRACK‐HD study, premanifest gene carriers (preHD), early manifest HD and controls were scanned at baseline and 2‐year follow‐up. Stratification of the preHD group into a far (preHD‐A) and near (preHD‐B) to predicted disease onset was performed. Age‐corrected histograms of whole‐brain white matter (WM), gray matter (GM) and striatal diffusion measures were computed and normalised by the number of voxels in each subject's data set.Principle observationsHigher cross‐sectional mean, axial and radial diffusivities were found in both WM (P ≤ 0.001) and GM (P ≤ 0.001) of the manifest HD compared to the preHD and control groups. In preHD, only WM axial diffusivity (AD) was higher than in controls (P ≤ 0.01). This finding remained valid only in preHD‐B (P ≤ 0.001). AD was also higher in the striatum of preHD‐B compared to controls and preHD‐A (P ≤ 0.01). Fractional anisotropy (FA) lacked sensitivity in differentiating between the groups. Histogram peak heights were generally lower in manifest HD compared to the preHD and control groups. No longitudinal differences were found in the degree of diffusivity change between the groups in the two year follow‐up. There was a significant relationship between diffusivity and neurocognitive measures.ConclusionsAlterations in cross‐sectional diffusion profiles between manifest HD subjects and controls were evident, both in whole‐brain and striatum. In the preHD stage, only AD alterations were found, a finding suggesting that this metric is a sensitive marker for early change in HD prior to disease manifestation. The individual diffusivities were superior to FA in revealing pathologic microstructural brain alterations. Diffusion measures were well related to clinical functioning and disease stage. Hum Brain Mapp 36:2061–2074, 2015. © 2015 Wiley Periodicals, Inc.
Healthcare Demand in the Presence of Discrete Price Changes
Authors: Gerfin Michael , Kaiser Boris , Schmid Christian 
Published: February 2015

SummaryDeductibles in health insurance generate nonlinear budget sets and dynamic incentives. Using detailed individual health expenditure data from a Swiss health insurer, we estimate the response in healthcare demand to the discrete price increase generated by resetting the deductible at the start of each calendar year. We find that for individuals with high deductibles, healthcare demand drops by 27%. The decrease is most pronounced for inpatient care and prescription drugs. By contrast, for individuals with low deductibles, there is no significant change in healthcare demand (except for prescription drugs). Overall our results suggest that healthy individuals respond much stronger to the price change. Copyright © 2015 John Wiley & Sons, Ltd.
Pooled analysis of the reports of pomalidomide after failure of lenalidomide and (or) bortezomib for multiple myeloma
Authors: Sheng Zhixin , Liu Guangyu 
Published: February 2015

AbstractThe use of pomalidomide after lenalidomide and (or) bortezomib failure in patients with multiple myeloma is not clearly clarified in clinical practice. We sought to compile the available clinical reports to better understand the effectiveness of pomalidomide after failure of lenalidomide and (or) bortezomib. We searched published reports including pomalidomide, lenalidomide and (or) bortezomib. Seven reports were identified. Pomalidomide‐based regimen was pomalidomide plus low‐dose dexamethasone (POM + LoDEX). Six randomized controlled trials enrolling a total of 641 patients that evaluated the treatment effects of pomalidomide after lenalidomide and (or) bortezomib failure in patients with multiple myeloma were included. Pooled results showed that the overall response rate (ORR) was 31% in the POM + LoDEX group. Analysis of heterogeneity showed very little (p = 0.997, I2 = 0%), suggesting that response rates of POM + LoDEX therapy were consistent across those included trials. Stable disease was achieved in 40% of 603 patients (heterogeneity: p = 0.980, I2 = 0%). In those >65 years, overall response was achieved in 32% of 71 patients (heterogeneity: p = 0.77, I2 = 0%). POM + LoDEX showed promising activity in the 95 patients with high‐risk cytogenetic abnormalities: ORR was 27% (heterogeneity: p = 0.97, I2 = 0%). In the pooled analysis, toxicity consisted primarily of myelosuppression: Grade 3 or 4 neutropenia was seen in 53% (heterogeneity: p = 0.857, I2 = 0%). Pomalidomide may produce clinical benefits in patients who had shown refractory on prior lenalidomide and (or) bortezomib therapy. Moreover, elder patients and high‐risk cytogenetic abnormalities were not negative predictors for pomalidomide response after lenalidomide and (or) bortezomib failure. Copyright © 2015 John Wiley & Sons, Ltd.