bluuebunny/crossref_metadata_2025_split huggingface dataset:
Skeletal Fat, Processing Intensity, and the Late Holocene Bison from Baker Cave, Southern Idaho
Authors: Breslawski Ryan P. , Byers David A. 
Published: January 2015

AbstractAlthough Idaho’s Snake River Plain contains a trans-Holocene record of bison exploitation, archaeologists have rarely investigated carcass butchery strategies in the region. We fill this knowledge gap with a study of bison remains from Baker Cave, a late Holocene processing site on the eastern Snake River Plain. We hypothesize that these remains resulted from fat-seeking behavior in response to winter fat scarcity. We explore this hypothesis with a series of variables designed to measure processing intensity: Impacts per Element, Percent Complete, and Number of Identified Specimens/Minimum Number of Elements. All three variables generate similarly strong correlations with skeletal fat utility, suggesting that Baker Cave’s inhabitants organized processing efforts around winter fat scarcity.
Bone Surface Modifications, Reasonable Certainty, and Human Antiquity in the Americas: The Case of the Arroyo Del Vizcaίno Site
Authors: Fariña Richard A. 
Published: January 2015

AbstractModifications on bone surfaces are taphonomic features that allow, among other aspects of environmental reconstruction, the assessment of human presence. The agents that cause such marks are diverse and of both biotic and abiotic origin. Among the former, marks made by human tools are of paramount importance for archaeologists and paleontologists to identify. Although it is possible to erroneously assign trampling marks to cut marks, several criteria have been recently developed so as to avoid such risks. These methods are applied here to the 30,000-year-old site of Arroyo del Vizcaíno (Uruguay), where over one thousand megafaunal remains have been collected. Some of them show marks that have been interpreted to be the result of the action of human tools. Using a database built up from previous studies of experimentally made marks as an actualistic model, it was concluded that the marks in the Arroyo del Vizcaíno site are unlikely to have been made by trampling, hence leaving human agency as the most feasible cause. This has important consequences for the debate on the human peopling of the Americas and on the process of extinction of the Pleistocene megafauna.
Multiscalar Perspectives on Social Networks in the Late Prehispanic Southwest
Authors: Mills Barbara J. , Peeples Matthew A. , Haas W. Randall , Borck Lewis , Clark Jeffery J. , Roberts John M. 
Published: January 2015

AbstractAnalyzing historical trajectories of social interactions at varying scales can lead to complementary interpretations of relationships among archaeological settlements. We use social network analysis combined with geographic information systems at three spatial scales over time in the western U.S. Southwest to show how the same social processes affected network dynamics at each scale. The period we address, A.D. 1200–1450, was characterized by migration and demographic upheaval. The tumultuous late thirteenth-century interval was followed by population coalescence and the development of widespread religious movements in the fourteenth and fifteenth centuries. In the southern Southwest these processes resulted in a highly connected network that drew in members of different settlements within and between different valleys that had previously been distinct. In the northern Southwest networks were initially highly connected followed by a more fragmented social landscape. We examine how different network textures emerged at each scale through 50-year snapshots. The results demonstrate the usefulness of applying a multiscalar approach to complex historical trajectories and the potential for social network analysis as applied to archaeological data.
How Animals Create Human History: Relational Ecology and the Dorset–Polar Bear Connection
Authors: Betts Matthew w. , Hardenberg Mari , Stirling Ian 
Published: January 2015

AbstractCarvings that represent polar bears (Ursus maritimus) are commonly found in Dorset Paleo-Eskimo archaeological sites across the eastern Arctic. Relational ecology, combined with Amerindian perspectivism, provides an integrated framework within which to comprehensively assess the connections between Dorset and polar bears. By considering the representational aspects of the objects, we reveal an ethology of polar bears encoded within the carvings’ various forms. Reconstructing the experiences and perceptions of Dorset as they routinely interacted with these creatures, and placing these interactions in socioeconomic, environmental, and historical context, permits us to decode a symbolic ecology inherent in the effigies. To the Dorset, these carvings were simultaneously tools and mnemonics (symbols). As tools, they were used to directly access the predatory and spiritual abilities of bears or, more prosaically, to teach and remind of the variety of proper hunting techniques available for capturing seals. As symbols, however, they were far more powerful, signaling how Dorset people conceptualized themselves and their place in the universe. Symbolic of an ice-edge way of life, the effigies expose the role that this special relationship with polar bears played in the creation of Dorset histories and identities.
Phylogenetic Relationships within Uvularia (Colchicaceae) Based on Morphology
Authors: Boyd Amy E. , Thalmayer Isaiah M. 
Published: January 2015

Abstract
The five species of bellworts in the genus Uvularia are common woodland herbs endemic to eastern North America. Two previous studies conducted phylogenetic analyses of Uvularia based on matK and rbcL gene sequences. The objective of this study was to create a phylogeny for Uvularia based on 18 qualitative morphological characters and 14 quantitative characters. Two phylogenetic analyses were performed, one including all 32 characters and one excluding the 14 quantitative characters. Strict consensus trees from the two analyses had the same topology and were congruent with published molecular phylogenies, supporting two sections of the genus.
Analysis of Protein Stability and Ligand Interactions by Thermal Shift Assay
Authors: Huynh Kathy , Partch Carrie L. 
Published: February 2015

AbstractPurification of recombinant proteins for biochemical assays and structural studies is time‐consuming and presents inherent difficulties that depend on the optimization of protein stability. The use of dyes to monitor thermal denaturation of proteins with sensitive fluorescence detection enables rapid and inexpensive determination of protein stability using real‐time PCR instruments. By screening a wide range of solution conditions and additives in a 96‐well format, the thermal shift assay easily identifies conditions that significantly enhance the stability of recombinant proteins. The same approach can be used as an initial low‐cost screen to discover new protein‐ligand interactions by capitalizing on increases in protein stability that typically occur upon ligand binding. This unit presents a methodological workflow for small‐scale, high‐throughput thermal denaturation of recombinant proteins in the presence of SYPRO Orange dye. © 2015 by John Wiley & Sons, Inc.
The impact of historical biases on the XBT‐derived meridional overturning circulation estimates at 34°S
Authors: Goes Marlos , Baringer Molly , Goni Gustavo 
Published: January 2015

AbstractAn observational system based on high‐density expendable bathythermograph (XBT) data has provided the longest record of the South Atlantic meridional overturning and heat transport estimates across 34°S. Measurement biases are a point of concern for the capability of an XBT system to capture long‐term trends in volume and heat transports, and the impact of such biases on the meridional overturning estimates has never been quantified. In the present study, the sensitivity of the meridional overturning circulation and heat transport to uncertainties in XBT measurements is quantified under the framework of an eddy‐resolving model simulation. Results show that XBT measurement biases after 2010 can translate into small meridional overturning errors on the order of 3% or 0.38 Sv (1Sv = 106 m3 s−1), and 0.025 PW (1 PW = 1015 W) or 8% of the meridional heat transport in the model. Historical XBT‐derived trends in transport estimates across 34°S are stronger and statistically significant after the late 1990s, 0.3 Sv decade−1 and 0.02 PW decade−1. These trends are mostly due to the XBT linear depth bias, with smaller contributions associated with temperature and depth offsets from the historical record. Long‐term trends calculated from Simple Ocean Data Assimilation reanalysis, estimated as 0.1 Sv/decade and 0.006 PW/decade, are 3 times smaller than the XBT‐derived historical trends. Therefore, an adequate correction of historical XBT data is necessary for an early detection of trends in the meridional overturning circulation and heat transport.
Detection of moving human micro‐Doppler signature in forest environments with swaying tree components by wind
Authors: Kilic Ozlem , Garcia‐Rubia Jose M. , Tran Nghia , Dang Vinh , Nguyen Quang 
Published: January 2015

AbstractThe objective of this paper is to investigate human motion in forest medium with swaying tree components due to time‐varying wind effects and to observe the characteristics of the received Doppler signature from the scene. We provide the results of an accurate model accounting for the key contributions to the Doppler signature in this scenario. A realistic walking motion is generated using an analytical model extracted from empirical data. The swaying canopy motion is modeled by employing a spring response mechanism to the wind force. The backscattered field calculations from the scene comprise of contributions from the forest (including trunks, branches, and the ground) and human, and the interactions between them. An analytical forest scattering model, which accounts for the ground effects, is used to calculate the contribution from the forest. The attenuation effects due to the vegetation are accounted for. In order to characterize the effects of human motion accurately, a full wave technique, namely, method of moments (MOM) enhanced with fast multipole method (FMM), is employed for the human scattering calculations. A parallel version of MOM‐FMM is implemented on a graphics processing unit based cluster to handle the large problem size. The human walking signatures created by the model are analyzed for different winds.
Selective and Potent Proteomimetic Inhibitors of Intracellular Protein–Protein Interactions
Authors: Barnard Anna , Long Kérya , Martin Heather L. , Miles Jennifer A. , Edwards Thomas A. , Tomlinson Darren C. , Macdonald Andrew , Wilson Andrew J. 
Published: January 2015

AbstractInhibition of protein–protein interactions (PPIs) represents a major challenge in chemical biology and drug discovery. α‐Helix mediated PPIs may be amenable to modulation using generic chemotypes, termed “proteomimetics”, which can be assembled in a modular manner to reproduce the vectoral presentation of key side chains found on a helical motif from one partner within the PPI. In this work, it is demonstrated that by using a library of N‐alkylated aromatic oligoamide helix mimetics, potent helix mimetics which reproduce their biophysical binding selectivity in a cellular context can be identified.
Condensed‐Phase, Halogen‐Bonded CF3I and C2F5I Adducts for Perfluoroalkylation Reactions
Authors: Sladojevich Filippo , McNeill Eric , Börgel Jonas , Zheng Shao‐Liang , Ritter Tobias 
Published: January 2015

AbstractA family of practical, liquid trifluoromethylation and pentafluoroethylation reagents is described. We show how halogen bonding can be used to obtain easily handled liquid reagents from gaseous CF3I and CF3CF2I. The synthetic utility of the new reagents is exemplified by a novel direct arene trifluoromethylation reaction as well as adaptations of other perfluoroalkylation reactions.
Palladium‐Catalyzed Regio‐ and Stereoselective Cross‐Addition of Terminal Alkynes to Ynol Ethers and Synthesis of 1,4‐Enyn‐3‐ones
Authors: Hari Babu Madala , Dwivedi Vikas , Kant Ruchir , Sridhar Reddy Maddi 
Published: January 2015

AbstractConjugated enynes, enol ethers, and enynones are versatile building blocks that can be elaborated by a wide variety of synthetic transformations. The selective synthesis of such units is a prerequisite for their effective utilization. The synthesis of conjugated 2‐phenoxyenynes through a palladium‐catalyzed cross‐addition of terminal alkynes to phenylethynyl ethers (hydroalkynylation) is now presented. The reaction is highly regio‐, stereo‐, and chemoselective, and shows excellent tolerance toward functional groups. The addition further features very mild reaction conditions (room temperature) and an inexpensive catalytic system (without a ligand and with a cheaply available Pd catalyst). The thus synthesized enynyl ethers with allylic hydroxy tethers, which survived the reaction, were shown to be ready precursors for valuable 1‐en‐4‐yn‐3‐ones.
Hydrogen‐Bonding Interactions Trigger a Spin‐Flip in Iron(III) Porphyrin Complexes
Authors: Sahoo Dipankar , Quesne Matthew G. , de Visser Sam P. , Rath Sankar Prasad 
Published: January 2015

AbstractA key step in cytochrome P450 catalysis includes the spin‐state crossing from low spin to high spin upon substrate binding and subsequent reduction of the heme. Clearly, a weak perturbation in P450 enzymes triggers a spin‐state crossing. However, the origin of the process whereby enzymes reorganize their active site through external perturbations, such as hydrogen bonding, is still poorly understood. We have thus studied the impact of hydrogen‐bonding interactions on the electronic structure of a five‐coordinate iron(III) octaethyltetraarylporphyrin chloride. The spin state of the metal was found to switch reversibly between high (S=5/2) and intermediate spin (S=3/2) with hydrogen bonding. Our study highlights the possible effects and importance of hydrogen‐bonding interactions in heme proteins. This is the first example of a synthetic iron(III) complex that can reversibly change its spin state between a high and an intermediate state through weak external perturbations.
Enantioselective Enzymes by Computational Design and In Silico Screening
Authors: Wijma Hein J. , Floor Robert J. , Bjelic Sinisa , Marrink Siewert J. , Baker David , Janssen Dick B. 
Published: January 2015

AbstractComputational enzyme design holds great promise for providing new biocatalysts for synthetic chemistry. A strategy to design small mutant libraries of complementary enantioselective epoxide hydrolase variants for the production of highly enantioenriched (S,S)‐diols and (R,R)‐diols is developed. Key features of this strategy (CASCO, catalytic selectivity by computational design) are the design of mutations that favor binding of the substrate in a predefined orientation, the introduction of steric hindrance to prevent unwanted substrate binding modes, and ranking of designs by high‐throughput molecular dynamics simulations. Using this strategy we obtained highly stereoselective mutants of limonene epoxide hydrolase after experimental screening of only 37 variants. The results indicate that computational methods can replace a substantial amount of laboratory work when developing enantioselective enzymes.
Enhancing the antifouling properties of polysulfone ultrafiltration membranes by the grafting of poly(ethylene glycol) derivatives via surface amidation reactions
Authors: Yu Haijun , Cao Yiming , Kang Guodong , Liu Zhongnan , Kuang Wu , Liu Jianhui , Zhou Meiqing 
Published: January 2015

ABSTRACTA carboxylic acid group was introduced on the polysulfone (PSF) membrane surface through a Friedel–Crafts reaction. Then, three kinds of poly(ethylene glycol) (PEG) derivatives were chosen to be immobilized on the PSF membrane surface via amide bonds. The membrane surface morphology, chemical composition, and hydrophilicity were investigated with scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, and water contact angle. The results indicate that PEG derivative immobilization effectively improved the antifouling properties of the PSF membranes. We found that prolonging the Friedel–Crafts reaction time or choosing the proper PEG derivative [methoxy poly(ethylene glycol) 550] could increase the surface hydrophilicity effectively and thus render the modified membranes better antifouling properties. The long‐term ultrafiltration experiment demonstrated the improvement of recycling properties and the reliability of the surface modification process. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41870.
Low dielectric and high thermal conductivity epoxy nanocomposites filled with NH2‐POSS/n‐BN hybrid fillers
Authors: Wu Yalan , Li Fang , Huyan Juanni , Zou Xiaorong , Li Ying 
Published: January 2015

ABSTRACTHybrid fillers of mono‐amine polyhedral oligomeric silsesquioxane/nanosized boron nitride (NH2‐POSS/n‐BN) were performed to fabricate NH2‐POSS/n‐BN/epoxy nanocomposites. Results revealed that the dielectric constant and dielectric loss values were decreased with the increasing addition of NH2‐POSS obviously, but increased with the increasing addition of BN fillers. For a given loading of NH2‐POSS (5 wt %), the thermal conductivities of NH2‐POSS/n‐BN/epoxy nanocomposites were improved with the increasing addition of n‐BN fillers, and the thermal conductivity of the nanocomposites was 1.28 W/mK with 20 wt % n‐BN fillers. Meantime, the thermal stability of the NH2‐POSS/n‐BN/epoxy nanocomposites was also increased with the increasing addition of n‐BN fillers. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41951.
Polypropylene membranes modified with interpenetrating polymer networks for the removal of chromium ions
Authors: Tapiero Yesid , Rivas Bernabé L. , Sánchez Julio , Bryjak Marek , Kabay Nalan 
Published: January 2015

ABSTRACTPolypropylene (PP) membranes incorporating poly[(ar‐vinylbenzyl) trimethylammonium chloride] P(ClVBTA), and poly[sodium (styrene sulfonate)] P(SSNa) were modified via an “in situ” radical polymerization synthesis. Two methods were used for impregnation of the reactive solution: pressure injection and plasma superficial activation with argon gas. The following conditions were varied: the monomer concentrations, number of injections, and cross‐linked concentration. The modified polypropylene membranes were then characterized using scanning electron microscopy/energy dispersive X‐ray spectroscopy, Fourier transform‐infrared spectroscopy, electrokinetic potential, and Donnan dialysis for the chromium ions transport. The modified membranes exhibited a hydrophilic character with a water uptake capacity between 15% and 20% and a percent modification between 2.5% and 4.0%. This was compared with the results of an unmodified polypropylene membrane as the blank and the mentioned polypropylene membrane has not the capacity to uptake water because this kind of material is highly hydrophobic. Hexavalent chromium ions were efficiently transported by the modified membranes containing P(ClVBTA) via a plasma method and it achieved 59.2% extraction at pH 9.0 using a 1‐mol L−1 NaCl extraction agent. Therefore, unmodified polypropylene membrane shows an extraction percentage close to 10% from the hexavalent chromium ions at pH 9.0. In the same way, the trivalent chromium transport using membranes modified with P(SSNa) achieved 49.0% extraction at pH 2.0 using 1 × 10−1 mol L−1 HNO3 and 1 mol L−1 NaCl as the extraction agents. Moreover, the unmodified polypropylene membrane reached a value close to 10% from the trivalent chromium ions using 1 × 10−1 mol L−1 HNO3 and 1 mol L−1 NaCl. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41953.
Assembly of Large Purely Inorganic Ce‐Stabilized/Bridged Selenotungstates: From Nanoclusters to Layers
Authors: Chen Wei‐Chao , Qin Chao , Li Yang‐Guang , Zang Hong‐Ying , Shao Kui‐Zhan , Su Zhong‐Min , Wang En‐Bo 
Published: January 2015

AbstractA versatile one‐pot strategy was used to synthesize two large, purely inorganic selenotungstates, nanocluster K6Na16[Ce6Se6W67O230(OH)6(H2O)17]⋅47 H2O (1) and layer K9Na5Ce(H2O)4[Ce6Se10W51O187(OH)7(H2O)18]⋅45 H2O (2), by combining cerium centers and SeO32− heteroanion templates. Compound 1 displays a Ce‐stabilized hexameric nanocluster with one rhombus‐like {W4O15(OH)3} unit in the center, whereas compound 2 is the first example of a Ce‐bridged layer selenotungstate network based on linkage of the unusual {Ce6Se10W51O187(OH)7(H2O)18} clusters and additional Ce(H2O)4 fragments via Ce‐O‐Se bridges. The compounds were characterized by elemental analyses, IR spectroscopy, thermogravimetric analyses, powder and single‐crystal X‐ray diffraction, and electrospray ionization mass spectrometry. Moreover, the electrochemical property of compound 1 was also investigated.
A Novel Boundary Control Solution for Unstable Heat Conduction Systems Based on Active Disturbance Rejection Control
Authors: Zhao Dong , Li Donghai , Wang Youqing 
Published: February 2015

AbstractIn this study, a new boundary control scheme is proposed for a class of unstable heat conduction systems based on active disturbance rejection control and frequency domain analysis methods. The unstable heat conduction systems studied here corresponds to a thin rod with surface heat loss and internal heat generation. An active disturbance rejection boundary controller is designed to stabilize the unstable heat conduction systems. Using the frequency domain analysis method, the Nyquist stability criterion for distributed parameter systems, the relative stability indices (gain margin, phase margin, and exponential stability speed) can be obtained for performance evaluation, and a constructive parameter‐tuning method for controller is proposed. Finally, it is proved that an active disturbance rejection boundary controller can stabilize the unstable heat conduction systems with one unstable pole, and the simulation results demonstrate that the temperature profile of the whole rod has good convergence properties under both Dirichlet and Neumann boundary control.