bluuebunny/crossref_metadata_2025_split huggingface dataset:
Like You Need a Hole in the Head: Tool Innovation a Possible Cause of Trephination. A Case from Kerma, Nubia
Authors: Martin D. C. 
Published: September 2011

ABSTRACTThis paper presents one case from Kerma (ind‐14.1.595 or K317) which was initially reported to have a ‘fatal traumatic wound’ in the front of the skull. The individual has a dime sized, circular hole with no radiating or concentric fracture lines associated with it. It also shows clear evidence of healing along the inside edges of the pathology. This was according to the preliminary, and only, analysis performed when excavated at Kerma (1913–1916), which was most likely performed by a crew member not formerly trained in anthropology, or medical science. Differential diagnosis will be discussed with respect to this lesion actually being a form of traumatic injury, possible remnants of a bony tumour, and trephination, among other diagnoses. Trephination has been identified in ancient Egypt and Nubian studies, though it is a rarity. Although trephination is a possible cause for the present lesion, this example does not fit the morphology of any other examples of the practise from this region or time period. Given that there have been similar borings witnessed on architecture from the Egyptian Old Kingdom, this lesion may suggest implementation of an already present architectural tool for medical purposes among the Kerma Nubians. Copyright © 2011 John Wiley & Sons, Ltd.
The use of silica gel coated with liquid paraffin as a stationary phase for chromatographic analysis of phytochemicals
Authors: Houghton P. J. , Osibogun I. M. 
Published: September 2011

AbstractThe development of the use of liquid paraffin as an impregnating agent for silica gel employed in chromatography is briefly reviewed. Its application to the isolation of polar chromone alkaloids and relatively non‐polar esters of long‐chain aliphatic acids and phenols is described.
The estimation of macromolecular synthesis in plant cell cultures
Authors: Mahady Gail B. , Beecher Christopher W. W. 
Published: September 2011

AbstractA simple and relatively rapid technique is described which can be used to determine accurately the overall pattern of macromolecule biosynthesis in plant cells. Sanguinaria canadensis L. (Papaveraceae) suspension cells were used as the model system. The patterns of DNA, RNA and protein synthesis were determined through cellular incorporation of [methyl‐3H]‐thymidine, [5‐3H]‐uridine and [4,5‐3H]‐leucine, respectively. The method takes advantage of a one‐step filtering procedure, which simplifies the extraction methods normally used. The results are described and possible applications of this procedure in plant‐cell growth studies and biotechnology are discussed.
The application of high‐speed countercurrent chromatography to the semipreparative separation of vincamine and vincine
Authors: Zhou Jin‐Yun , Fang Qi‐Cheng , Lee Yu‐Wei 
Published: September 2011

AbstractHigh‐speed countercurrent chromatography (HSCCC) has gained increasing popularity in the isolation of bioactive natural products. This paper reports its application to the separation of the alkaloids vincamine and vincine which differ only by a methoxy group. It is demonstrated in this study that the resolution and speed of HSCCC is comparable to high‐performance liquid chromatography (HPLC) and its capability in semi‐preparative purification via continuous sample injections can be a very useful application in phytochemical research·alkaloids; vincamine; vincine; high‐speed countercurrent chromatography
Ultradrawing properties of ultrahigh‐molecular weight polyethylene/functionalized carbon nanotube fibers and transmittance properties of their gel solutions
Authors: Yeh Jen‐Taut , Wu Tsong‐Wei , Lai Yu‐Ching , Li Qi‐Cheng , Zhou Huo‐Peng , Zhou Qin , Tsou Chi‐Hui , Shu Yao‐Chi , Huang Chi‐Yuan , Huang Kuo‐Shien 
Published: September 2011

AbstractThe influences of the dispersion level of carbon nanotubes (CNTs) and functionalized CNTs on the transmittance properties of ultrahigh‐molecular weight polyethylene (UHMWPE) gel solutions and on ultradrawing properties of their as‐prepared fibers are reported. The transmittance properties suggest that the dispersion level of functionalized CNTs in UHMWPE/functionalized CNTs gel solution is significantly better than plain CNTs in UHMWPE/CNTs gel solutions. The orientation factors, achievable draw ratios, tensile strength (σf), and modulus (E) values of UHMWPE/CNTs (FxCy) and UHMWPE/functionalized CNTs (FxCf‐y) as‐prepared fiber specimens reached a maximum value as their CNT and functionalized CNT contents approached optimum contents at 0.00015 and 0.0001 wt%, respectively. The σf and E values of both FxC0.0012 and FxCf‐0.001 series fiber specimens prepared at their optimum CNT and functionalized CNT contents reached another maximum as their UHMWPE approached optimum UHMWPE concentration of 1.7 wt%. Possible reasons accounting for these interesting properties are proposed. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Polymerization of ethylene using amido functional half‐sandwich complexes of group 4 metals
Authors: Rajesh A. , Sivaram S. 
Published: September 2011

AbstractLigands (C13H9)(2,6‐R2C6H3NH)SiPh2 [R = iPr (2a), Me (2b)] were synthesized by single deprotonation of the amino group in 2,6‐dialkylanilines with n‐BuLi at −78°C followed by reaction with fluorenyl diphenyl silyl chloride [FluSi(Ph2)Cl]. Single crystal X‐ray diffraction studies revealed different geometries around the nitrogen atom for the two compounds. Titanium and zirconium complexes (3a–3d) were prepared by double deprotonation of the ligands with n‐butyl lithium (n‐BuLi) followed by reaction with the respective metal chlorides, MCl4 (THF) 2. Polymerization of ethylene was performed using these complexes as catalyst precursors along with methylaluminoxane (MAO) as an activator at 5 bar pressure. Complexes 3a–3d/MAO exhibited moderate catalyst activities for polymerization of ethylene and resulted in high molecular weight linear poly(ethylene)s (Mv > 4 × 105 g/mol). Catalyst activities were much lower when compared to similar N‐alkyl substituted complexes presumably due to the resonance effect of the aromatic group on the amido nitrogen. POLYM. ENG.SCI., 2011. © 2011 Society of Plastics Engineers
Broadband dielectric spectroscopy studies of glassy‐state relaxations in annealed poly(2,5‐benzimidazole)
Authors: Nalawade Amol , Hassan Mohammad K. , Jarrett William A. , Mauritz Kenneth A. , Litt Morton H. 
Published: September 2011

AbstractA broadband dielectric spectroscopic (BDS) study of poly(2,5‐benzimidazole) revealed three sub‐glass relaxations and the manner in which the time scales of these local molecular motions shift with annealing temperature and time. Also issuing from the BDS studies was a trend in the degree of connectivity of charge migration pathways and conductivity with annealing temperature and time. These studies were complemented with dynamic mechanical analysis, which showed the same relaxations, and solid state 1H and 13C NMR studies that showed hydrogen bonding group mobility versus temperature. Wide angle X‐ray diffraction investigations indicated an increase in chain‐packing efficiency that was used to rationalize the BDS and NMR results. Copyright © 2011 Society of Chemical Industry
Thermodynamically induced self‐assembled electrically conductive networks in carbon‐black‐filled ternary polymer blends
Authors: Shen Lie , Wang Fangquan , Jia Weican , Yang Hui 
Published: September 2011

AbstractBy calculating the surface tensions of the components, composites with innovative thermodynamically induced self‐assembled electrically conductive networks were designed, prepared and investigated. Carbon black (CB) was added into a ternary blend system comprised of poly(methyl methacrylate) (PMMA), ethylene–acrylic acid copolymer (EAA) and polypropylene (PP). Scanning electron microscopy images show that the PMMA/EAA/PP ternary blend forms a tri‐continuous phase structure like a sandwich, in which PMMA and PP form a co‐continuous phase while EAA spreads at the interface of the PMMA and PP phases as a sheath. The micrographs and resistivity–temperature characteristic curve results indicate that CB fillers are selectively located at the interface of the PMMA and PP phases, namely the EAA phase. The percolation threshold of PMMA/EAA‐CB/PP composites is 0.2 vol%, which is only one‐fifth of that of PP/CB composites. Copyright © 2011 Society of Chemical Industry
Rigorous optical modeling and optimization of thin‐film photovoltaic cells with textured transparent conductive oxides
Authors: Agrawal Mukul , Frei Michel 
Published: September 2011

ABSTRACTTypical thin‐film photovoltaic (PV) cells incorporate a textured transparent conductive oxide to enhance light trapping and efficiently harvest solar energy. Rigorous coherent optical simulations of these devices and a complete characterization of these textured films are a challenging problem because of the several orders of magnitude difference between the wavelengths of interest and the spatial dimension of the sample that needs to be evaluated. In this paper, a practical approach for rigorous and predictive modeling of optical properties of thin‐film PV cells incorporating a vast variety of light‐trapping structures including semi‐coherent textured films and patterned coherent structures is presented. In contrast to the existing semi‐empirical device models, it is demonstrated that the presented methodology can accurately predict the scattering properties of textured fluorine‐doped tin oxide and aluminum‐doped zinc oxide conductive transparent films. It is further shown that the optical response of single‐junction and tandem‐junction PV devices incorporating such films can also be predicted with good accuracy as compared with the measured results. Next, a methodology to identify the sufficient statistical fingerprints of semi‐coherent textured films that are needed to unambiguously predict the light propagation in thin‐film cells is presented. This comprehensive approach then lends itself to identifying the optimal surface morphology needed for strong light trapping. This rigorous approach automatically includes the effects of important loss mechanisms such as the surface plasmon‐enhanced absorption in textured metal surfaces that are otherwise very difficult to account for semi‐coherent approaches based on scalar scattering theory. Copyright © 2011 John Wiley & Sons, Ltd.
An improved method for the construction of decoy peptide MS/MS spectra suitable for the accurate estimation of false discovery rates
Authors: Ahrné Erik , Ohta Yuki , Nikitin Frederic , Scherl Alexander , Lisacek Frederique , Müller Markus 
Published: September 2011

AbstractThe relevance of libraries of annotated MS/MS spectra is growing with the amount of proteomic data generated in high‐throughput experiments. These reference libraries provide a fast and accurate way to identify newly acquired MS/MS spectra. In the context of multiple hypotheses testing, the control of the number of false‐positive identifications expected in the final result list by means of the calculation of the false discovery rate (FDR). In a classical sequence search where experimental MS/MS spectra are compared with the theoretical peptide spectra calculated from a sequence database, the FDR is estimated by searching randomized or decoy sequence databases. Despite on‐going discussion on how exactly the FDR has to be calculated, this method is widely accepted in the proteomic community. Recently, similar approaches to control the FDR of spectrum library searches were discussed. We present in this paper a detailed analysis of the similarity between spectra of distinct peptides to set the basis of our own solution for decoy library creation (DeLiberator). It differs from the previously published results in some key points, mainly in implementing new methods that prevent decoy spectra from being too similar to the original library spectra while keeping important features of real MS/MS spectra. Using different proteomic data sets and library creation methods, we evaluate our approach and compare it with alternative methods.
Large‐scale N‐glycoproteome map of rat brain tissue: Simultaneous characterization of insoluble and soluble protein fractions
Authors: Qiao Xiaoqiang , Tao Dingyin , Qu Yanyan , Sun Liangliang , Gao Liang , Zhang Xiaodan , Liang Zhen , Zhang Lihua , Zhang Yukui 
Published: September 2011

AbstractThe large‐scale N‐glycosylation analysis is critical for biomedical research, since a variety of diseases are found to be associated with glycoproteins. By a combination of glycoprotein analysis in insoluble protein fraction solubilized with 1% v/v 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIM BF4) and those in soluble fraction, a total number of 462 non‐redundant N‐glycoprotein groups, including 316 transmembrane glycoproteins, were successfully identified. Correspondingly, 849 unique N‐glycosites were confidently recognized. The data set could provide a support for the further in‐depth research of brain N‐glycosylation, such as for the discovery of candidate drug targets and biomarkers.
Differential profiling studies of N‐linked glycoproteins in glioblastoma cancer stem cells upon treatment with γ‐secretase inhibitor
Authors: Dai Lan , Liu Yashu , He Jintang , Flack Callie G. , Talsma Caroline E. , Crowley Jessica G. , Muraszko Karin M. , Fan Xing , Lubman David M. 
Published: September 2011

AbstractWe have recently demonstrated that Notch pathway blockade by γ‐secretase inhibitor (GSI) depletes cancer stem cells (CSCs) in Glioblastoma Multiforme (GBM) through reduced proliferation and induced apoptosis. However, the detailed mechanism by which the manipulation of Notch signal induces alterations on post‐translational modifications such as glycosylation has not been investigated. Herein, we present a differential profiling work to detect the change of glycosylation pattern upon drug treatment in GBM CSCs. Rapid screening of differential cell surface glycan structures has been performed by lectin microarray on live cells followed by the detection of N‐linked glycoproteins from cell lysates using multi‐lectin chromatography and label‐free quantitative mass spectrometry analysis. A total of 51 and 52 glycoproteins were identified in the CSC‐ and GSI‐treated groups, respectively, filtered by a combination of decoy database searching and Trans‐Proteomic Pipeline (TPP) processing. Although no significant changes were detected from the lectin microarray experiment, 7 differentially expressed glycoproteins with high confidence were captured after the multi‐lectin column including key enzymes involved in glycan processing. Functional annotations of the altered glycoproteins suggest a phenotype transformation of CSCs toward a less tumorigenic form upon GSI treatment.
Proteomic profiling of oil bodies isolated from the unicellular green microalga Chlamydomonas reinhardtii: With focus on proteins involved in lipid metabolism
Authors: Nguyen Hoa M. , Baudet Mathieu , Cuiné Stéphan , Adriano Jean‐Marc , Barthe Damien , Billon Emmanuelle , Bruley Christophe , Beisson Fred , Peltier Gilles , Ferro Myriam , Li‐Beisson Yonghua 
Published: September 2011

AbstractOil bodies are sites of energy and carbon storage in many organisms including microalgae. As a step toward deciphering oil accumulation mechanisms in algae, we used proteomics to analyze purified oil bodies from the model microalga Chlamydomonas reinhardtii grown under nitrogen deprivation. Among the 248 proteins (≥2 peptides) identified by LC‐MS/MS, 33 were putatively involved in the metabolism of lipids (mostly acyl‐lipids and sterols). Compared with a recently reported Chlamydomonas oil body proteome, 19 new proteins of lipid metabolism were identified, spanning the key steps of the triacylglycerol synthesis pathway and including a glycerol‐3‐phosphate acyltransferase (GPAT), a lysophosphatidic acid acyltransferase (LPAT) and a putative phospholipid:diacylglycerol acyltransferase (PDAT). In addition, proteins putatively involved in deacylation/reacylation, sterol synthesis, lipid signaling and lipid trafficking were found to be associated with the oil body fraction. This data set thus provides evidence that Chlamydomonas oil bodies are not only storage compartments but also are dynamic structures likely to be involved in processes such as oil synthesis, degradation and lipid homeostasis. The proteins identified here should provide useful targets for genetic studies aiming at increasing our understanding of triacyglycerol synthesis and the role of oil bodies in microalgal cell functions.
Symbol nomenclature for representing glycan structures: Extension to cover different carbohydrate types
Authors: Harvey David J. , Merry Anthony H. , Royle Louise , Campbell Matthew P. , Rudd Pauline M. 
Published: September 2011

AbstractThis Viewpoint article addresses comments made on our original article describing a symbolic system for the depiction of N‐ and O‐linked carbohydrate structures and proposes a method for extending the symbol set to include monosaccharides commonly found in carbohydrates present in bacteria and plants. As before, basic monosaccharides are shown by shape with one or more additions such as solid fill or additions of lines, crosses or dots to represent functional groups. The use of colour to differentiate constituent monosaccharides is avoided, thus enabling the system to be used in a variety of formats. Linkage and anomericity are shown by the angle and type of line connecting the symbols. In this extended version, new symbols are proposed for additional hexoses and it is proposed that pyranose and furanose forms of the monosaccharides could be shown by solid or broken outlines to the symbols. Conventions for depicting the presence of multiple functional groups such as deoxy‐(NH2)2 are also discussed. It is hoped that these proposals will stimulate discussion so that a consensus can be reached as to how the glycobiology community can best convey complex information in a simple manner.
Protein recovery and identification from the gulf killifish, Fundulus grandis: Comparing snap‐frozen and RNAlater® preserved tissues
Authors: Abbaraju Naga V. , Cai Yang , Rees Bernard B. 
Published: September 2011

AbstractReliable proteomic analysis of biological tissues requires sampling approaches that preserve proteins as close to their in vivo state as possible. In the current study, the patterns of protein abundance in one‐dimensional (1‐D) gels were assessed for five tissues of the gulf killifish, Fundulus grandis, following snap‐freezing tissues in liquid nitrogen or immersion of fresh tissues in RNAlater®. In liver and heart, the protein profiles in 1‐D gels were better preserved by snap‐freezing, while in gill, the 1‐D protein profile was better preserved by immersion in RNAlater®. In skeletal muscle and brain, the two approaches yielded similar patterns of protein abundance. LC‐MS/MS analyses and database searching resulted in the identification of 17 proteins in liver and 12 proteins in gill. Identified proteins include enzymes of energy metabolism, structural proteins, and proteins serving other biological functions. These protein identifications for a species without a sequenced genome demonstrate the utility of F. grandis as a model organism for environmental proteomic studies in vertebrates.
A kinetic investigation of surfactant‐free emulsion polymerization of styrene using laponite clay platelets as stabilizers
Authors: Sheibat‐Othman Nida , Cenacchi‐Pereira Ana‐Maria , Santos Amilton Martins Dos , Bourgeat‐Lami Elodie 
Published: September 2011

AbstractWe report the kinetics and mechanism of soap‐free emulsion polymerization of styrene using laponite platelets as stabilizers. The polymerization was initiated by potassium persulfate and the latex particles were stabilized by laponite platelets dispersed in water. Laponite adsorption on the polymer particles was enhanced by the addition of poly(ethylene glycol) monomethylether methacrylate (PEGMA). Particle nucleation can be described using the classical homogeneous nucleation mechanism followed by coagulation of unstable precursors. Oligomeric radicals formed in the water phase become insoluble and precipitate on the laponite surface leading to primary precursor particles composed of a few polymer chains and one or several clay platelets. Mature latex particles are then generated by coagulation and growth of the previously formed precursor particles. Both the nucleation and initial aggregation rates increased in the presence of PEGMA. Calorimetric monitoring of the polymerization allowed estimating the heat produced by the reaction and the monomer conversion. Hence, using the monomer material balance, the number of radicals in the polymer particles could be estimated precisely. The average number of radicals per particle,
, was found to be high in the range 3–6. This result was attributed to strong attractive interactions between the growing radicals and the clay surface. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011.
Modeling highly branched structures: Description of the solution structures of dendrimers, polyglycerol, and glycogen
Authors: Konkolewicz Dominik , Perrier Sébastien , Stapleton David , Gray‐Weale Angus 
Published: September 2011

AbstractWe show that Random Branching Theory (RBT) accurately describes the structures of various synthetic and natural highly branched polymers in solution. We test the theory against data taken from the literature, including radii of gyration of glycogen, hyperbranched polyglycerols, and polyamidoamine dendrimers and the small‐angle X‐ray scattering profiles of these same dendrimers. In particular, all these polymers can be described adequately by sequentially branching units, packed together in a random close packing arrangement. Combined with previous tests against experiments and computer simulations, the evidence presented here shows that RBT is a simple, but surprisingly useful, theory of highly branched polymers' solution structure. We suggest that it is sufficiently powerful to be useful in the design of new polymers. Our most surprising conclusion is that random attachment of component parts produces a good model of regularly branched polymers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1525–1538, 2011