bluuebunny/crossref_metadata_2025_split huggingface dataset:
Male lineages in South American native groups: Evidence of M19 traveling south
Authors: Toscanini Ulises , Gusmão Leonor , Berardi Gabriela , Gomes Verónica , Amorim António , Salas Antonio , Raimondi Eduardo 
Published: August 2011

AbstractWith this study, we aimed to determine the different male ancestral components of two Native American communities from Argentina, namely Toba and Colla. The analysis of 27 Y‐chromosome SNPs allowed us to identify seven different haplogroups in both samples. Chromosomes carrying the M3 mutation, which typically defines the Native American haplogroup Q1a3a, were seen most frequently in the Toba community (90%). Conversely, Q1a3a was represented in 34% of the Colla Y‐chromosomes, whereas haplogroup R1b1, the main representative of western European populations, exhibited the highest frequency in this population (41%). Different M3 sublineages in the Toba community could be identified by observing point mutations at both DYS385 and M19 loci. A microvariant at DYS385, named 16.1, has been characterized, which helps to further subdivide Q1a3a. It is the first time the M19 mutated allele is described in a population from Argentina. This finding supports the old age of the lineages carrying the M19 mutation, but it contradicts the previous hypothesis that the M19 mutated allele is confined to only two Equatorial‐Tucano population groups from the north region of South America. The detection of M19 further south than previously thought allows questioning of the hypothesis that this lineage serves as an example of isolation after colonization. This observation also affirms the strong genetic drift to which Native Americans have been subjected. Moreover, our study illustrates a heterogeneous contribution of Europeans to these populations and supports previous studies showing that most Native American groups were subjected to European admixture that primarily involved immigrant men. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
Status and health in Roman Dorset: The effect of status on risk of mortality in post‐conquest populations
Authors: Redfern Rebecca C. , DeWitte Sharon N. 
Published: August 2011

AbstractThe Roman conquest of Britain was previously shown to have negatively impacted health, particularly for children, older adults, and men. We build upon this previous research by investigating the effect that status had on risks of mortality within the Roman Britain populations of Dorset. This study incorporates a sample of 291 individuals excavated from several cemeteries in the county of Dorset dating between the first to early fifth centuries AD. To assess the effect of status on risks of mortality, burial type was used as a proxy for status and modeled as a covariate affecting the Siler and Gompertz–Makeham models of mortality. The results of these analyses indicate that high‐status individuals, particularly children, had a lower mortality risk compared to lower‐status groups; and for those buried in urban cemeteries, higher‐status individuals of all age‐groups had a lower mortality risk. As with our previous study (Redfern and DeWitte: Am J Phys Anthropol 144 (2011) 269–285), we found that male mortality risk was higher than females, which we consider to reflect underlying sex‐differences in immunity and disease response. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
mtDNA diversity in azara's owl monkeys (Aotus azarai azarai) of the Argentinean Chaco
Authors: Babb Paul L. , Fernandez‐Duque Eduardo , Baiduc Caitlin A. , Gagneux Pascal , Evans Sian , Schurr Theodore G. 
Published: August 2011

AbstractOwl monkeys (Aotus spp.) inhabit much of South America yet represent an enigmatic evolutionary branch among primates. While morphological, cytogenetic, and immunological evidence suggest that owl monkey populations have undergone isolation and diversification since their emergence in the New World, problems with adjacent species ranges, and sample provenance have complicated efforts to characterize genetic variation within the genus. As a result, the phylogeographic history of owl monkey species and subspecies remains unclear, and the extent of genetic diversity at the population level is unknown. To explore these issues, we analyzed mitochondrial DNA (mt DNA) variation in a population of wild Azara's owl monkeys (Aotus azarai azarai) living in the Gran Chaco region of Argentina. We sequenced the complete mitochondrial genome from one individual (16,585 base pairs (bp)) and analyzed 1,099 bp of the hypervariable control region (CR) and 696 bp of the cytochrome oxidase II (COII) gene in 117 others. In addition, we sequenced the mitochondrial genome (16,472 bp) of one Nancy Ma's owl monkey (A. nancymaae). Based on the whole mtDNA and COII data, we observed an ancient phylogeographic discontinuity amongAotusspecies living north, south, and west of the Amazon River that began more than eight million years ago. Our population analyses identified three major CR lineages and detected a high level of haplotypic diversity withinA. a. azarai. These data point to a recent expansion of Azara's owl monkeys into the Argentinean Chaco. Overall, we provide a detailed view of owl monkey mtDNA variation at genus, species, and population levels. © Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
Die Pictet‐Spengler‐Reaktion in der Natur und der organischen Chemie
Authors: Stöckigt Joachim , Antonchick Andrey P. , Wu Fangrui , Waldmann Herbert 
Published: August 2011

AbstractAlkaloide sind eine bedeutende Klasse von Naturstoffen, die in der Natur weit verbreitet sind und von vielen Organismen gebildet werden. Sie haben ein breites Spektrum an biologischen Wirkungen und wurden viele Jahre in der Volksmedizin angewendet. Auch heutzutage haben Alkaloide zahlreiche Anwendungen als medizinische Therapeutika und verfügen außerdem über einen hohen Stellenwert als Ausgangspunkt für die Wirkstoffsuche, weshalb ihre Synthese von beträchtlichem Interesse ist. Die wichtigste Methode für die Synthese von Alkaloidgerüsten ist die durch Pictet und Spengler entdeckte Kondensationsreaktion, deren Leistungsfähigkeit in der Synthese von stereochemisch und strukturell komplexen Alkaloiden überzeugend bewiesen wurde.
The Pictet–Spengler Reaction in Nature and in Organic Chemistry
Authors: Stöckigt Joachim , Antonchick Andrey P. , Wu Fangrui , Waldmann Herbert 
Published: August 2011

AbstractAlkaloids are an important class of natural products that are widely distributed in nature and produced by a large variety of organisms. They have a wide spectrum of biological activity and for many years were used in folk medicine. These days, alkaloids also have numerous applications in medicine as therapeutic agents. The importance of these natural products in inspiring drug discovery programs is proven and, therefore, their continued synthesis is of significant interest. The condensation discovered by Pictet and Spengler is the most important method for the synthesis of alkaloid scaffolds. The power of this synthesis method has been convincingly proven in the construction of stereochemicaly and structurally complex alkaloids.
Morphology, reversible phase crystallization, and thermal sensitive shape memory effect of cellulose whisker/SMPU nano‐composites
Authors: Han Jianping , Zhu Yong , Hu Jinlian , Luo Hongsheng , Yeung Lap‐Yan , Li Wenguo , Meng Qinghao , Ye Guangdou , Zhang Sheng , Fan Ying 
Published: August 2011

AbstractTo investigate the morphology, crystallization properties of reversible phase and thermal sensitive shape memory properties of CW/SMPU (Cellulose Whisker/Shape Memory Polyurethane) nano‐composite, the CW/SMPU nano‐composite having CW contents of 0.1–3.8 wt % were prepared. SEM investigation showed the evolution of reversible phase morphology from spherolite crystallization structure to uniform matrix with tiny CW aggregates with the addition of CW into the SMPU matrix. DSC and isothermal crystallization kinetic method revealed the effect of CW on crystallization properties of reversible phase and fixed phase, suggesting that the effect of CW on the crystallization of hard segment phase is not comparable with thermal history; the more CW causes the higher crystallization rate of reversible phase; the crystallization mechanism of reversible phase in nano‐composite gradually evolves to heterogeneous nucleation and crystal growth in two dimensions with the increase of CW content; the excellent nucleation effect of CW for the reversible phase leads to the drop of activity energy from 134.1 kJ/mol (N‐0), to 95.1 kJ/mol (N‐4). Cyclic tensile tests illustrate the addition of CW content can engender rapid shape fixity ability after a relative short cooling time; the shape fixity ratio of nano‐composite and the control sample after sufficient cooling all can be identically high. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Nonisothermal cure of bisphenol epoxy resin with a nonlinear aliphatic polyamine hardener
Authors: Zhou Dapeng , Wang Hongmei , Wang Songsong , Liu Dan , Lian Yuan 
Published: August 2011

AbstractThe amino terminated polypropylenimine dendrimer (DAB‐dendri‐(NH2)4) was employed as a new nonlinear aliphatic curing agent for diglycidyl ether of bisphenol A (DGEBA). Nonisothermal curing reaction kinetics of DGEBA/DAB was investigated with a differential scanning calorimeter (DSC). The apparent reaction activation energy Ea is about 56.7 kJ/mol determined using the Kissinger equation, and a two‐parameter (m, n) autocatalytic model ([icirc]Sesták–Berggren equation) was confirmed to be able to well simulate the reaction kinetics in the light of the Málek method. In addition, the relation between reaction activation energy Ea and curing degree α was obtained by applying model‐free isoconversional analysis with the Kissinger‐Akahira‐Sunose (KAS) method. As α increases, Ea reduced quickly from >80 kJ/mol to ≈60 kJ/mol up to a ≈ 15%, then decreased slowly to 55 kJ/mol till a ∼ 75%, and finally dropped to 44 kJ/mol at full conversion. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Precipitation polymerization of molecularly imprinted polymers for recognition of melamine molecule
Authors: Zhang Zhongcan , Cheng Zhiqiang , Zhang ChunFeng , Wang Hongyan , Li Junfeng 
Published: August 2011

AbstractMolecular imprinted polymer microspheres (MIPs) were prepared by precipitation polymerization using melamine as template molecule, methacrylic acid (MAA) as functional monomer, trimethylol‐propane trimethacrylate (TRIM) as crosslinking agent, acetonitrile as solvent and dispersion medium. Release of the template was performed by continuous extraction with methanol containing 10% acetic acid. The microspheres were observed by scanning electron microscopy (SEM). The perfect microspheres were produced when the addition of crosslinker was 7.48 mmol. The binding capacity of MIPs was examined, Qmax = 68.36 μmol g−1, and the dissociation constant at binding site of MIPs, Kd = 0.761, was estimated. Compared with the performance of conventional imprinted polymer, the imprinted microspheres showed high selectivity in special binding to template molecule. The imprinted microspheres could be used as the stationary phase in HPLC or SPE for selective extraction of melamine in daily products. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Effect of the microstructure parameters on the mullins softening in carbon‐black filled styrene–butadiene rubbers
Authors: Merckel Yannick , Diani Julie , Brieu Mathias , Gilormini Pierre , Caillard Julien 
Published: August 2011

AbstractA quantitative estimate of the Mullins softening is proposed and tested on various carbon‐black filled styrene–butadiene rubbers. To model the behavior of elastomeric materials, some constitutive equations reported in the literature are based on the account of a strain amplification factor, which evolves with the maximum strain history. The amplification factor is grounded on the representation of filled rubbers as heterogeneous materials made of hard rigid domains and soft deformable domains. In this work, this factor is split into two parts with opposite effects that account for the Mullins softening and for the filler reinforcement, respectively. Evolutions of both parts are obtained through a direct analysis of cyclic uniaxial tensile tests performed on a series of materials. The Mullins softening part is shown to linearly depend on the filler volume fraction and on the maximum strain applied, when defined as the first invariant of the Hencky tensor. Its changes with the gum cross‐link density parameter are insignificant. The reinforcement part of the amplification factor shows quadratic dependence on the filler volume fraction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Photo‐fabricated unsaturated polyester resin composites reinforced by kenaf fibers, synthesis and characterization
Authors: Hussein M. A. , Tay G. S. , Rozman H. D. 
Published: August 2011

AbstractNew bio‐fiber composites (UPRC) cured by ultraviolet radiation were produced using kenaf fiber as reinforcing agent and unsaturated polyester resins as matrix in the presence of styrene and IRGACURE 1800 as photoinitiator. Unsaturated polyester resins based on palm oil were prepared from various ratios of monoglyceride (MG)/maleic anhydride (MA) by the interaction of the corresponding MG monomer, with different equivalents of MA, in the presence of 2‐methylimidazole as catalyst. The various characteristics of the obtained bio‐fiber composites, including mechanical, gel content, water absorption and thickness swelling test, thermal analysis, were determined and the data were discussed. Bio‐fiber composite with MG: MA ratio (1 : 4 eq./eq.) showed better mechanical properties (tensile, flexural, and impact strength) than other formulations. Gel content increased as the amount of MA was increased up to the MG: MA ratio was 1 : 4 (eq./eq.) then slightly decreased at the higher ratio formulation. Bio‐fiber composite (UPRCc) was considered the best prepared bio‐fiber composite which contained higher degree double bond, cross‐linking and thermal stability. Moreover, morphological study of selected examples of the formed bio‐fiber composites was also carried out and showed the evidence of the enhancement of the compatibility between fiber and polymer matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The virtual anatomy laboratory: Usability testing to improve an online learning resource for anatomy education
Authors: Doubleday Eldridge G. , O'Loughlin Valerie D. , Doubleday Alison F. 
Published: August 2011

AbstractAn increasing number of instructors are seeking to provide students with online anatomy resources. Many researchers have attempted to identify associations between resource use and student learning but few studies discuss the importance of usability testing in resource design and modification. Usability testing provides information about ease of use and resource flexibility and indicates navigational issues that contribute to extraneous cognitive load for the user. An example of usability testing for modification of an online anatomy resource called the “Virtual Lab” is presented. Usability testing was used to determine whether increased content would impair navigation through the interface. Subjects with varying levels of experience with anatomy content were recruited to assess efficiency and effectiveness (defined by usability standards) of the original resource and of the redesigned resource. Comparisons between usability evaluation of the original “Virtual Lab” (OVL) and of the redesigned “Virtual Lab” (RVL) revealed that subjects were better able to successfully complete tasks using the RVL than they were with the OVL. Results also demonstrated that subjects did not take significantly more time to successfully complete tasks with the RVL. Additionally, usability testing revealed that subjects were able to successfully complete tasks using the RVL regardless of whether they possessed prior experience with anatomy content or not. Results of this study suggest that the modified resource is more effective for users. The example presented here underscores the need for usability testing prior to resource implementation and whenever significant changes are made to a resource interface. Anat Sci Educ. © 2011 American Association of Anatomists.
The changes of stemness biomarkers expression in human adipose‐derived stem cells during long‐term manipulation
Authors: Wan Safwani Wan Kamarul Zaman , Makpol Suzana , Sathapan Somasundaram , Chua Kien Hui 
Published: August 2011

AbstractOne of the advantages of human adipose‐derived stem cells (ASCs) in regenerative medicine is that they can be harvested in abundance. However, the stemness biomarkers, which marked the safety and efficacy of ASCs in accordance with the good manufacturing practice guidelines, is not yet well established. This study was designed to investigate the effect of long‐term culture on the stemness properties of ASCs using quantitative real‐time polymerase chain reaction and flow cytometry. Results showed the growth rate of ASCs was at its peak when they reached P10 (population doubling; PD = 26) but started to decrease when they were expanded to P15 (PD = 36) and P20 (PD = 46). The ASCs can be culture expanded with minimal alteration in the stemness genes and cluster of differentiation (CD) markers expression up to P10. Expression level of Sox2, Nestin, and Nanog3 was significantly decreased at later passage. CD31, CD45, CD117, and human leukocyte antigen DR, DQ, and DP were lowly expressed at P5 and P10 but their expressions increased significantly at P15 or P20. The differentiation ability of ASCs (adipogenesis, osteogenesis, and neurogenesis) also decreased in long‐term culture. Our findings suggested that P10 (PD = 26) should be the “cutoff point” for clinical usage because ASCs at passage 15 onward showed significant changes in the stemness genes, CD markers expression, and differentiation capability.
The Chiampo River 30 Years Later: Long‐Term Effects of Environmental Regulations on Social Representations
Authors: Brondi Sonia , Sarrica Mauro , Cibin Roberto , Neresini Federico , Contarello Alberta 
Published: August 2011

ABSTRACTWith the aim of addressing environmental concerns from an applied social psychological perspective, this study explores how regulations aimed at reducing industrial pollution contribute to short‐term and long‐term changes in social representations. The local river in a Valley characterised by strong interactions between industries and communities was the focus of concern. Three features of the representations were examined: images, emotional experiences and practices. The research followed a multi‐method approach, using reports completed by 11‐to 14‐year‐old school pupils and collected in three periods: 1974–1977; 1978–1980; 2007–2009. In the third time period, interviews and surveys were also collected. Textual data underwent lexicometric analyses and qualitative content analyses; quantitative data underwent descriptive and inferential analyses. Results show that effective regulations contributed to positive change in social representations of the river. After 30 years, however, tensions between elements of the representation are present. Images and emotional experiences of the river considerably improved, so much so that the river almost disappears from the focus of attention. Practices however are consistent with old representations of the water as noxious, indicating persistent concerns about potential pollution. Results suggest the desirability of continuing participatory engagement between citizens and local/environmental authorities, not only as new regulations are introduced but also after they have been enacted. Copyright © 2011 John Wiley & Sons, Ltd.
Violet‐to‐Blue Tunable Emission of Aryl‐Substituted Dispirofluorene–Indenofluorene Isomers by Conformationally‐Controllable Intramolecular Excimer Formation
Authors: Thirion Damien , Poriel Cyril , Métivier Rémi , Rault‐Berthelot Joëlle , Barrière Frédéric , Jeannin Olivier 
Published: August 2011

AbstractTwo series of DiSpiroFluorene–IndenoFluorene (DSF‐IF) positional isomers, namely dispiro[2,7‐diarylfluorene‐9′,6,9′′,12‐indeno[1,2‐b]fluorenes], (1,2‐b)‐DSF‐IFs 1 and dispiro[2,7‐diarylfluorene‐9′,6,9′′,12‐indeno[2,1‐a]fluorenes], (2,1‐a)‐DSF‐IFs 2 have been synthesized. These violet‐to‐blue fluorescent emitters possess a 3π‐2spiro architecture, which combines via two spiro links two different indenofluorene cores, that is, (1,2‐b)‐IF or (2,1‐a)‐IF and 2,7‐substituted‐diaryl‐fluorene units. Due to their different geometric profiles, the two families of positional isomers present drastically different properties. The marked difference observed between the properties of (1,2‐b)‐DSF‐IF (1) and (2,1‐a)‐DSF‐IF (2) is discussed in terms of intramolecular π–π interactions occurring in (2,1‐a)‐DSF‐IF (2) leading to conformationally‐controllable intramolecular excimer formation. Indeed, the original geometry of the (2,1‐a)‐DSF‐IF (2) family, with face‐to‐face “aryl‐fluorene‐aryl” moieties, leads to remarkable excimer emission through intramolecular π–π interactions in the excited state. Furthermore, the emission wavelengths can be gradually modulated by the control of the steric hindrance between the adjacent substituted phenyl rings. Thus, through a comparative and detailed study of the 1H NMR, electrochemical and photophysical properties of DSF‐IFs 1 and 2, we have evidenced the intramolecular π–π interactions occurring between the two “aryl‐fluorene‐aryl” moieties in the ground state and in the excited state. These properties have been finally correlated to the spectacular conformational change modeled by density functional theory (DFT) calculations. Indeed, the two “aryl‐fluorene‐aryl” moieties switch from a staggered conformation in the ground state to an eclipsed conformation in the first excited state.
Cyanide‐Bridged [Fe8M6] Clusters Displaying Single‐Molecule Magnetism (M=Ni) and Electron‐Transfer‐Coupled Spin Transitions (M=Co)
Authors: Mitsumoto Kiyotaka , Oshiro Emiko , Nishikawa Hiroyuki , Shiga Takuya , Yamamura Yasuhisa , Saito Kazuya , Oshio Hiroki 
Published: August 2011

AbstractCyanide‐bridged metal complexes of [Fe8M6(μ‐CN)14(CN)10 (tp)8(HL)10(CH3CN)2][PF6]4⋅n CH3CN⋅m H2O (HL=3‐(2‐pyridyl)‐5‐[4‐(diphenylamino)phenyl]‐1H‐pyrazole), tp−=hydrotris(pyrazolylborate), 1: M=Ni with n=11 and m=7, and 2: M=Co with n=14 and m=5) were prepared. Complexes 1 and 2 are isomorphous, and crystallized in the monoclinic space group P21/n. They have tetradecanuclear cores composed of eight low‐spin (LS) FeIII and six high‐spin (HS) MII ions (M=Ni and Co), all of which are bridged by cyanide ions, to form a crown‐like core structure. Magnetic susceptibility measurements revealed that intramolecular ferro‐ and antiferromagnetic interactions are operative in 1 and in a fresh sample of 2, respectively. Ac magnetic susceptibility measurements of 1 showed frequency‐dependent in‐ and out‐of‐phase signals, characteristic of single‐molecule magnetism (SMM), while desolvated samples of 2 showed thermal‐ and photoinduced intramolecular electron‐transfer‐coupled spin transition (ETCST) between the [(LS‐FeII)3(LS‐FeIII)5(HS‐CoII)3(LS‐CoIII)3] and the [(LS‐FeIII)8(HS‐CoII)6] states.