bluuebunny/crossref_metadata_2025_split huggingface dataset:
Palladium‐Catalyzed, Chelation‐Assisted Stereo‐ and Regioselective Synthesis of Tetrasubstituted Olefins by Oxidative Heck Arylation
Authors: Lee Hyun Seung , Kim Ko Hoon , Kim Sung Hwan , Kim Jae Nyoung 
Published: August 2012

AbstractAn efficient synthesis of tetrasubstituted olefins was achieved via a palladium‐catalyzed, chelation‐assisted oxidative Heck arylation protocol from trisubstituted olefins bearing a tether with a directing group in a completely stereo‐ and regioselective manner. The stereo‐ and regioselectivity as well as excellent yields of tetrasubstituted olefins originated from the stabilization of a palladium intermediate by chelation between the palladium center and a directing group.
Application of Tethered Ruthenium Catalysts to Asymmetric Hydrogenation of Ketones, and the Selective Hydrogenation of Aldehydes
Authors: Jolley Katherine E. , Zanotti‐Gerosa Antonio , Hancock Fred , Dyke Alan , Grainger Damian M. , Medlock Jonathan A. , Nedden Hans G. , Le Paih Jacques J. M. , Roseblade Stephen J. , Seger Andreas , Sivakumar Vilvanathan , Prokes Ivan , Morris David J. , Wills Martin 
Published: August 2012

AbstractAn improved method for the synthesis of tethered ruthenium(II) complexes of monosulfonylated diamines is described, together with their application to the hydrogenation of ketones and aldehydes. The complexes were applied directly, in their chloride form, to asymmetric ketone hydrogenation, to give products in excess of 99% ee in the best cases, using 30 bar of hydrogen at 60 °C, and to the selective reduction of aldehydes over other functional groups.
Dual Heterogeneous Catalysis for a Regioselective Three‐ Component Synthesis of Bi‐ and Tri(hetero)arylpyridines
Authors: Allais Christophe , Liéby‐Muller Frédéric , Constantieux Thierry , Rodriguez Jean 
Published: August 2012

AbstractWe have designed a new, user‐friendly oxidative dual heterogeneous catalytic system capable of promoting polysubstituted pyridines as unique products from simple activated Michael acceptors, 1,3‐dicarbonyls and ammonium acetate. This metal‐free environmentally‐respectful and totally regioselective domino reaction proved to be a great strategy to access bi‐ and triaryl‐type pyridines as well as challenging bi‐ and triheteroaryl‐type pyridines in a single operation.
Palladium(II)‐Catalyzed Hydration of Alkynylphosphonates to β‐Ketophosphonates
Authors: Li Xiubin , Hu Gaobo , Luo Ping , Tang Guo , Gao Yuxing , Xu Pengxiang , Zhao Yufen 
Published: August 2012

AbstractA highly efficient palladium(II)‐catalyzed hydration of a wide range of alkynylphosphonates to the corresponding β‐ketophosphonates has been developed to give high yields at 80 °C in 1, 4‐dioxane, with no acidic or alkaline cocatalysts required. The described catalytic system should provide an efficient alternative to highly toxic mercury‐catalyzed methodologies and be useful in synthetic programs.
Aluminum Triflate as a Powerful Catalyst for Direct Amination of Alcohols, Including Electron‐Withdrawing Group‐Substituted Benzhydrols
Authors: Ohshima Takashi , Ipposhi Junji , Nakahara Yasuhito , Shibuya Ryozo , Mashima Kazushi 
Published: August 2012

AbstractDirect aminations of allylic alcohols, benzylic alcohols, and benzhydrols with electron‐withdrawing (F, Br, I, NO2, or CN) substituents were efficiently catalyzed by aluminum triflate [Al(OTf)3] to afford the corresponding biarylamines in high yield, and the dibromo‐substituted product was further transformed into letrozole.
Quantifying patterns of endocranial heat distribution: Brain geometry and thermoregulation
Authors: Bruner Emiliano , De La Cuétara José Manuel , Musso Fabio 
Published: August 2012

AbstractObjectives:The mechanisms involved in brain thermoregulation are still poorly known, and many disagreements still exist concerning the selective cooling capacity of the brain volume. This issue has also been discussed in human evolution and paleoneurology, speculating on possible changes associated with hominid encephalization. Although the vascular system is supposed to be the main component responsible for thermoregulation, brain geometry also plays an important role in the pattern of heat distribution.Methods:In fossils, the only neuroanatomical evidence available for quantitative analyses is the endocranial form, molded by the brain morphology. Here, we present a quantitative method based on numerical simulations to quantify and localize variation in heat dissipation patterns associated with endocranial morphological changes, presenting a case‐study on modern humans and chimpanzees.Results:Thermic maps provide a graphic tool to visualize heat loading on the endocranial surface. The distribution of the values (thermic spectrum) supplies a quantification which can help describe and compare the patterns of heat distribution within and between groups. Absolute values are largely influenced by size differences. Normalized values suggest further differences associated with brain shape.Conclusions:Simulation and numerical modeling are useful to provide a descriptive and quantitative approach to endocranial thermoregulation, supplying a quantitative tool to investigate ontogenic and phylogenetic changes. This is particularly relevant in paleoneurology, considering the large shape and size differences described for fossil hominid brains. Am. J. Hum. Biol., 2012. © 2012 Wiley Periodicals, Inc.
Autistic disorder phenotype associated to a complex 15q intrachromosomal rearrangement
Authors: Christofolini Denise Maria , Meloni Vera Ayres , de Paula Ramos Marco Antonio , Oliveira Mariana Moysés , de Mello Claudia Berlim , Pellegrino Renata , Takeno Sylvia Satomi , Melaragno Maria Isabel 
Published: August 2012

AbstractThe proximal regions of acrocentric chromosomes, particularly 15q11.2, are frequently involved in structural rearrangement. However, interstitial duplications involving one of the chromosome 15 homologues are less frequent, with few patients described with molecular techniques. These patients present distinctive clinical findings including developmental delay and intellectual disability, minor dysmorphic facial features, epilepsy, and autistic behavior. Here we describe an interstitial rearrangement of chromosome 15 composed of a triplication ∼6.9 Mb from 15q11.2 to 15q13.2 followed by a duplication of ∼2.4 Mb from 15q13.2 to 15q13.3, defined using different approaches as MLPA, qPCR, array and FISH. FISH revealed that the middle part of the triplicated segment was in inverted position. The parental origin of the rearrangement was assessed using methylation assay and SNP array that revealed the maternal origin of the additional material. The patient presents most of the clinical features associated to 15q11.2 triplication: minor dysmorphic facial features, generalized epilepsy, absence seizures, intellectual disability, and autistic behavior. In conclusion, the use of more accurate molecular tools enabled a detailed investigation, providing the identification of intrachromosome duplication/triplication and bringing new light to the study of genetic causes of autistic disorders. © 2012 Wiley Periodicals, Inc.
Rare variants in TMEM132D in a case–control sample for panic disorder
Authors: Quast Carina , Altmann Andre , Weber Peter , Arloth Janine , Bader Daniel , Heck Angela , Pfister Hildegard , Müller‐Myhsok Bertram , Erhardt Angelika , Binder Elisabeth B. 
Published: August 2012

AbstractGenome‐wide association studies have identified common variants associated with common diseases. Most variants, however, explain only a small proportion of the estimated heritability, suggesting that rare variants might contribute to a larger extent to common diseases than assumed to date. Here, we use next‐generation sequencing to test whether such variants contribute to the risk for anxiety disorders by re‐sequencing 40 kb including all exons of the TMEM132D locus which we have previously shown to be associated with panic disorder and anxiety severity measures. DNA from 300 patients suffering from anxiety disorders, mostly panic disorder (84.7%), and 300 healthy controls was screened for the presence of genetic variants using next‐generation re‐sequencing in a pooled approach. Results were verified by individual re‐genotyping. We identified 371 variants of which 247 had not been reported before, including 15 novel non‐synonymous variants. The majority, 76% of these variants had a minor allele frequency less than 5%. While we did not identify additional common variants in TMEM132D associated with panic disorders, we observed an overrepresentation of presumably functional coding variants in healthy controls as compared to cases as well as a higher rate of private coding variants in cases, with one non‐synonymous coding variant present in four patients but not in any of the matched controls nor in over 5,500 individuals of different ethnic origins from publicly available re‐sequencing datasets. Our data suggest that not only common but also putatively functional and/or rare variants within TMEM132D might contribute to the risk to develop anxiety disorders. © 2012 Wiley Periodicals, Inc.
The STREAM X Multichannel GPR System: First Test at Vieil‐Evreux (France) and Comparison with Other Geophysical Data
Authors: Novo Alexandre , Dabas Michel , Morelli Gianfranco 
Published: August 2012

ABSTRACTA new multichannel ground‐penetrating radar (GPR) system was tested at the Gallo‐Roman site of Vieil‐Evreux (Evreux, France). The resultant maps are compared with previous ones obtained with the ARP© system and other standard geophysical techniques at the same site. Results show how full‐resolution GPR data acquisition methodologies, together with a robust integration of navigation and positioning mounted on a vehicle for fast prospection, provide the best results. The objective of this work was to present the results of the first test of the system STREAM X as a new option for non‐destructive prospection of large archaeological sites. Copyright © 2012 John Wiley & Sons, Ltd.
Crystal Structure of Quinine: The Effects of Vinyl and Methoxy Groups on Molecular Assemblies of Cinchona Alkaloids Cannot Be Ignored
Authors: Hisaki Ichiro , Hiraishi Eri , Sasaki Toshiyuki , Orita Hideo , Tsuzuki Seiji , Tohnai Norimitsu , Miyata Mikiji 
Published: August 2012

AbstractQuinine, one of Cinchona alkaloids, has been of great interest from medical, synthetic, and supramolecular viewpoints. However, unaccountably, the guest‐free (GF) crystal of quinine containing no solvent or other molecules has not been reported for nearly three decades, although GF crystals of other Cinchona alkaloids, such as quinidine, cinchonidine, and cinchonine, are already known. In this study, we successfully revealed the crystal structure of quinine, which belongs to the P21 space group with the cell parameters of a=6.0587(1), b=19.2492(5), c=22.2824(7) Å, β=92.1646(11)°, and V=2596.83(12) Å3. Interestingly, the crystal has three crystallographically independent molecules in the cell (Z′=3) that are connected through a N(quinoline)⋅⋅⋅HO hydrogen bond to form a pseudo three‐two‐fold (32) double‐helical motif. The helical motif is completely different from those observed in GF crystals of other Cinchona alkaloids. Hierarchical comparison on the crystal structures of a series of Cinchona alkaloids including quinine clearly demonstrated that only small structural differences of a molecule, particularly the position of the vinyl group, cause a significant variety of assembly manner in the crystalline state. There have been no reports systematically demonstrating such steric effect in crystals of Cinchona alkaloids, and, therefore, the present system contributes to the design of desired functional crystal structures.
Changes in Negative Reciprocity as a Function of Age
Authors: Bereby‐Meyer Yoella , Fiks Shelly 
Published: August 2012

ABSTRACTStandard economic models assume people exclusively pursue material self‐interests in social interactions. However, people exhibit social preferences; that is, they base their choices partly on the outcomes others obtained in a social interaction. People care about fairness, and reciprocity affects behavior. This study examines the differences in negative reciprocity (costly punishment for unfair divisions) as a function of age. Sixty‐one kindergarteners (5‐year‐olds), 53 second graders (8‐year‐olds), and 57 sixth graders (12‐year‐olds) played a dictator game or a mini–ultimatum game either with a human proposer or with a random machine that determined the division between the two players. By keeping the divisions between the players constant and varying the source of the unfair proposal, we were able to differentiate between reciprocity‐based and inequality‐aversion preferences. We found that kindergarteners proposed and accepted unfair divisions regardless of the source of the offer, behaving according to the standard economic model. Children in the sixth grade tended to reject unfair offers from a human proposer but accept unfair divisions from a random device, indicating the emergence of negative reciprocity preferences by age eight (and contrary to inequality aversion). Children at this age also tended to give more fair offers in the ultimatum game than in the dictator game, indicating the emergence of strategic thinking. Copyright © 2012 John Wiley & Sons, Ltd.
Epigenetics meets mathematics: Towards a quantitative understanding of chromatin biology
Authors: Steffen Philipp A. , Fonseca João P. , Ringrose Leonie 
Published: August 2012

AbstractHow fast? How strong? How many? So what? Why do numbers matter in biology? Chromatin binding proteins are forever in motion, exchanging rapidly between bound and free pools. How do regulatory systems whose components are in constant flux ensure stability and flexibility? This review explores the application of quantitative and mathematical approaches to mechanisms of epigenetic regulation. We discuss methods for measuring kinetic parameters and protein quantities in living cells, and explore the insights that have been gained by quantifying and modelling dynamics of chromatin binding proteins.
Integration of bioinformatics into an undergraduate biology curriculum and the impact on development of mathematical skills
Authors: Wightman Bruce , Hark Amy T. 
Published: August 2012

AbstractThe development of fields such as bioinformatics and genomics has created new challenges and opportunities for undergraduate biology curricula. Students preparing for careers in science, technology, and medicine need more intensive study of bioinformatics and more sophisticated training in the mathematics on which this field is based. In this study, we deliberately integrated bioinformatics instruction at multiple course levels into an existing biology curriculum. Students in an introductory biology course, intermediate lab courses, and advanced project‐oriented courses all participated in new course components designed to sequentially introduce bioinformatics skills and knowledge, as well as computational approaches that are common to many bioinformatics applications. In each course, bioinformatics learning was embedded in an existing disciplinary instructional sequence, as opposed to having a single course where all bioinformatics learning occurs. We designed direct and indirect assessment tools to follow student progress through the course sequence. Our data show significant gains in both student confidence and ability in bioinformatics during individual courses and as course level increases. Despite evidence of substantial student learning in both bioinformatics and mathematics, students were skeptical about the link between learning bioinformatics and learning mathematics. While our approach resulted in substantial learning gains, student “buy‐in” and engagement might be better in longer project‐based activities that demand application of skills to research problems. Nevertheless, in situations where a concentrated focus on project‐oriented bioinformatics is not possible or desirable, our approach of integrating multiple smaller components into an existing curriculum provides an alternative.
Mild cognitive impairment: effect of education on the verbal and nonverbal tasks performance decline
Authors: Vadikolias Konstantinos , Tsiakiri‐Vatamidis Anna , Tripsianis Grigorios , Tsivgoulis Georgios , Ioannidis Panagiotis , Serdari Aspasia , Heliopoulos John , Livaditis Miltos , Piperidou Charitomeni 
Published: August 2012

AbstractWe sought to longitudinally evaluate the potential association of educational level with performance on verbal and nonverbal tasks in individuals with mild cognitive impairment (MCI). We evaluated patients with MCI, age >50 years, no medication intake, absent vascular risk factors, and no lesions on brain magnetic resonance imaging (MRI). Each patient underwent a clinical assessment packet and a series of neuropsychological tests of the language and constructional praxis subtests of Cambridge Cognitive Examination (CAMGOG) and the Boston naming test (BNT), at baseline, 6 months, and 12 months. Educational levels were defined taking into account the total years of education, the school level, and diplomas. MCI patients with low education level showed a stepwise reduction in scores of naming objects (NO; P = 0.009), definition (DF; P = 0.012), language (LT; P = 0.021), constructional praxis (CD; P = 0.022), confrontation naming skills (BXB; P = 0.033), phonemic help (BFB; P = 0.041), and BNT (P = 0.002). Analysis of covariance, controlling for baseline scores, showed that education was associated with NO score (P = 0.002), DF score (P = 0.005), LT (P = 0.008), CD score (P = 0.008), BXB score (44.36 ± 1.84, P = 0.0001), BFB (P = 0.022), and BNT (P = 0.004). Our findings indicate that education appeared to affect verbal and nonverbal task performance in MCI patients. Despite the fact that higher educated patients are more acquainted with the tasks, slower deterioration in consecutive follow‐up examinations could be explained by the cognitive reserve theory. The potential association of this protective effect with delayed onset of symptoms deserves further investigation.
Considering water availability and the effect of solute concentration on high solids saccharification of lignocellulosic biomass
Authors: Selig Michael J. , Hsieh Chia‐Wen Carmen , Thygesen Lisbeth G. , Himmel Michael E. , Felby Claus , Decker Stephen R. 
Published: August 2012

AbstractMilliliter scale (ligno)cellulose saccharifications suggest general solute concentration and its impact on water availability plays a significant role in detrimental effects associated with high solids lignocellulose conversions. A microtumbler developed to enable free‐fall mixing at dry solids loadings up to 35% (w/w) repeatedly produced known detrimental conversion trends on cellulose, xylan and pretreated lignocellulose with commercial enzymes. Despite this, high concentrations of insoluble nonhydrolysable dextrans did not depress saccharification extents in 5% (w/w) cellulose slurries suggesting mass transfer limitations may not significantly limit hydrolysis extents at high solids loadings. Interestingly, cellulose saccharification by purified cellulases showed increased conversions with increasing dry solids loadings. This prompted investigations into impacts the concentration of soluble species, such as sugar alcohols, low molecular weight enzyme preparation components, and monomer hydrolysis products, have on the hydrolysis environment. Such substances significantly depress conversion rates and were shown to correlatively lower water activity (Aw) in the hydrolysis environment while high insoluble solids concentrations did not. Furthermore, low‐field NMR on concentrated slurries of insoluble complex carbohydrates, including the nonhydrolysable dextrans, showed all solids constrained water significantly more than high concentrations of soluble species (inhibitory) suggesting water constraint may not be as problematic an issue at high solids loadings compared to the availability of water in the system. Additionally, the introduction of soluble species lessened overall water constraint in high solids systems and appears to shift the distribution of water away from insoluble surfaces. This is potentially a critical issue for industrial processes operating at high dry solids levels. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Solvent selection and optimization of α‐chymotrypsin‐catalyzed synthesis of N‐Ac‐Phe‐Tyr‐NH2 using mixture design and response surface methodology
Authors: Hu Shih‐Hao , Kuo Chia‐Hung , Chang Chieh‐Ming J. , Liu Yung‐Chuan , Chiang Wen‐Dee , Shieh Chwen‐Jen 
Published: August 2012

AbstractA peptide, N‐Ac‐Phe‐Tyr‐NH2, with angiotensin I‐converting enzyme (ACE) inhibitor activity was synthesized by an α‐chymotrypsin‐catalyzed condensation reaction of N‐acetyl phenylalanine ethyl ester (N‐Ac‐Phe‐OEt) and tyrosinamide (Tyr‐NH2). Three kinds of solvents: a Tris–HCl buffer (80 mM, pH 9.0), dimethylsulfoxide (DMSO), and acetonitrile were employed in this study. The optimum reaction solvent component was determined by simplex centroid mixture design. The synthesis efficiency was enhanced in an organic‐aqueous solvent (Tris‐HCl buffer: DMSO: acetonitrile = 2:1:1) in which 73.55% of the yield of N‐Ac‐Phe‐Tyr‐NH2 could be achieved. Furthermore, the effect of reaction parameters on the yield was evaluated by response surface methodology (RSM) using a central composite rotatable design (CCRD). Based on a ridge max analysis, the optimum condition for this peptide synthesis included a reaction time of 7.4 min, a reaction temperature of 28.1°C, an enzyme activity of 98.9 U, and a substrate molar ratio (Phe:Tyr) of 1:2.8. The predicted and the actual (experimental) yields were 87.6 and 85.5%, respectively. The experimental design and RSM performed well in the optimization of synthesis of N‐Ac‐Phe‐Tyr‐NH2, so it is expected to be an effective method for obtaining a good yield of enzymatic peptide. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012
Using growth factor conditioning to modify the properties of human cell derived extracellular matrix
Authors: Wolchok Jeffrey C. , Tresco Patrick A. 
Published: August 2012

AbstractWe have recently reported on a bench‐top approach for isolating extracellular matrix (ECM) from pure populations of cells grown in culture using sacrificial, open‐celled foams to concentrate and capture the ECM. To increase both the accumulation and the strength of the ECM harvested, cell‐seeded polyurethane (PU) foams were cultured in media supplemented with either transforming growth factor β‐1 (TGFβ1) or hepatocyte growth factor (HGF). At the end of a 3‐week culture period, ECM yield was significantly increased for samples conditioned in supplemented media. Control foams yielded 48 ± 12 mg of material for every gram of PU foam seeded. Yield values increased to 102 ± 21 and 243 ± 25 mg for HGF and TGFβ1‐treated samples, respectively. HGF supplementation increased the modulus by 59%, while TGFβ1 treatment increased the elastic modulus by 204%. TGFβ1‐stimulated material was organized into a network that was markedly denser than control material, with HGF‐stimulated network density intermediate to TGFβ1 and controls. Our study showed that TGFβ1‐treated samples were collagen enriched while HGF samples had an increased gylcosaminoglycan concentration. The results demonstrate that growth factor supplementation, particularly with TGFβ1, can significantly alter the biomechanical properties of cell‐derived ECM that may be used for therapeutic applications. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012