bluuebunny/crossref_metadata_2025_split huggingface dataset:
ChemInform Abstract: Quantum Magnetism and Criticality
Authors: Sachdev Subir 
Published: June 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Characterization and Optimization of Chemical Synthesis Using Real Time Vibrational Spectroscopy
Authors: Homsi Fadi , Barrett Paul , Wang Jian , Ferwerda Roel 
Published: June 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Probing Proton—Proton Proximities in the Solid State
Authors: Brown Steven P. 
Published: June 2008

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Interleukin‐6 predicts recurrence and survival among head and neck cancer patients
Authors: Duffy Sonia A. , Taylor Jeremy M.G. , Terrell Jeffrey E. , Islam Mozaffarul , Li Yun , Fowler Karen E. , Wolf Gregory T. , Teknos Theodoros N. 
Published: June 2008

AbstractBACKGROUND.Increased pretreatment serum interleukin (IL)‐6 levels among patients with head and neck squamous cell carcinoma (HNSCC) have been shown to correlate with poor prognosis, but sample sizes in prior studies have been small and thus unable to control for other known prognostic variables.METHODS.A longitudinal, prospective cohort study determined the correlation between pretreatment serum IL‐6 levels, and tumor recurrence and all‐cause survival in a large population (N = 444) of previously untreated HNSCC patients. Control variables included age, sex, smoking, cancer site and stage, and comorbidities. Kaplan‐Meier plots and univariate and multivariate Cox proportional hazards models were used to study the association between IL‐6 levels, control variables, and time to recurrence and survival.RESULTS.The median serum IL‐6 level was 13 pg/mL (range, 0‐453). The 2‐year recurrence rate was 35.2% (standard error, 2.67%). The 2‐year death rate was 26.5% (standard error, 2.26%). Multivariate analyses showed that serum IL‐6 levels independently predicted recurrence at significant levels [hazard ratio (HR) = 1.32; 95% confidence interval (CI), 1.11 to 1.58; P = .002] as did cancer site (oral/sinus). Serum IL‐6 level was also a significant independent predictor of poor survival (HR = 1.22; 95% CI, 1.02 to 1.46; P = .03), as were older age, smoking, cancer site (oral/sinus), higher cancer stage, and comorbidities.CONCLUSIONS.Pretreatment serum IL‐6 could be a valuable biomarker for predicting recurrence and overall survival among HNSCC patients. Using IL‐6 as a biomarker for recurrence and survival may allow for earlier identification and treatment of disease relapse. Cancer 2008. © 2008 American Cancer Society.
Synthesis of Pyranoid and Furanoid Glycals from Glycosyl Sulfoxides by Treatment with Organolithium Reagents
Authors: Gómez Ana M. , Casillas Marta , Barrio Aitor , Gawel Anna , López J. Cristóbal 
Published: June 2008

AbstractGlycosyl sulfoxides can be conveniently transformed into pyranoid or furanoid glycals by treatment with organolithium reagents. The more likely reaction pathway involves a sulfoxide/metal exchange reaction to generate a glycosyllithium derivative that undergoes β‐elimination of its C‐2 substituent. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Control and performance of health care systems. A comparative analysis of 19 OECD countries
Authors: Kotzian Peter 
Published: June 2008

AbstractThis paper performs an empirical comparison of health systems.Health systems are seen as networks of delegation relationships among principals and agents, subject to agency problems. Following the institutional economics approach, a health system's efficiency is considered to be determined by the existence and treatment of agency problems. Agency problems can be controlled by mechanisms built into the health system, or can also be controlled by an external actor, for example, the government, either by using the instruments available or by conducting institutional reforms. To explain differences in the amenability of a country's health system to external governmental control, I combine the veto player approach and the incentives for societal actors to exert influence, into the concept of indirect veto players: the more indirect veto players exist, the less external control will be exercised.I derive indicators capturing both forms of control and perform a comparison of health systems based on institutional and performance data. Using data reducing methods, I identify two dimensions of control underlying the institutional setting of the health system and three dimensions of health system performance. The relationships found between control and performance confirm the hypotheses derived from the adopted theoretical approach. Copyright © 2008 John Wiley & Sons, Ltd.
Steric repulsions, rotation barriers, and stereoelectronic effects: A real space perspective
Authors: Pendás A. Martín , Blanco M. A. , Francisco E. 
Published: June 2008

AbstractWidely used chemical concepts like Pauli repulsion or hyperconjugation, and their role in determining rotation barriers or stereoelectronic effects, are analyzed from the real space perspective of the interacting quantum atoms approach (IQA). IQA emerges from the quantum theory of atoms in molecules (QTAIM), but is free from the equilibrium geometry constraint of the former. A framework with both electronically unrelaxed and relaxed wavefunctions is presented that leads to an approximate correspondence between the IQA concepts and those used in the EDA (energy decomposition analysis) or NBO (natural bond orbital) procedures. We show that no net force acts upon the electrons in an electronically relaxed system, so that any reasonable definition of Pauli repulsion must involve unrelaxed state functions. Using antisymmetrized fragments clarifies that Pauli repulsions are energetically connected to the IQA deformation energies, leaving footprints in the finally relaxed states. Similarly, EDA or NBO hyperconjugative stabilizations are found to be naturally related to the IQA electron delocalization patterns. Applications to the rotation barrier of ethane and other simple systems are presented, and the very often forgotten role of electrostatic contributions in determining preferred conformations is highlighted. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
The transcription factors HeBlimp and HeT‐brain of an indirectly developing polychaete suggest ancestral endodermal, gastrulation, and sensory cell‐type specification roles
Authors: Arenas‐Mena Cesar 
Published: June 2008

AbstractThe expression of Blimp and T‐brain was characterized during embryogenesis of the indirectly developing polychaete Hydroides elegans. The expression of both genes in the vegetal blastomeres of this lophotrochozoan is restricted to the lateral and oral regions of the blastopore. Both transcription factors also have expression patterns consistent with ancestral neural functions. HeBlimp is expressed in a couple of animal cap cells and exhibits a marked left bias that correlates with earlier development of the left eye in H. elegans. HeT‐brain is expressed in animal cap blastomeres and eventually becomes restricted to apical tuft cells of early trochophore stages. The expression of Blimp and T‐brain among directly and indirectly developing bilaterians suggests ancestral sensory cell‐type specification, gastrulation by invagination, endoderm specification, mesoderm specification, and/or tripartite gut subdivision. These characterizations add to the long‐term goal of understanding the regulatory evolution functions that underlies complex life cycles in metazoans. J. Exp. Zool. (Mol. Dev. Evol.) 310B:567–576, 2008. © 2008 Wiley‐Liss, Inc.
Characterization of soapstock and deodorizer distillates of vegetable oils using gas chromatography
Authors: Dumont Marie‐Josée , Narine Suresh S. 
Published: June 2008

AbstractSoapstock and deodorizer distillates are complex lipid mixtures that are produced in significant amounts by the vegetable oil refining process. These mixtures contain components such as fatty acids, sterols, squalene and tocopherols that have important commercial value and therefore their characterization and quantification are of interest. We describe here the development of a simple gas chromatography (GC) method based on a silylation derivatization technique coupled with the use of a medium polar column to separate the different classes of fatty compounds in these waste streams. This method is suitable for GC coupled with either a flame ionization detector or a mass spectrometer.
Multipliers of Laplace transform type for ultraspherical expansions
Authors: Martinez Teresa 
Published: June 2008

AbstractWe define and investigate the multipliers of Laplace transform type associated to the differential operator Lλf (θ) = –f ″(θ) – 2λ cot θf ′(θ) + λ2f (θ), λ > 0. We prove that these operators are bounded in Lp ((0, π), dmλ) and of weak type (1, 1) with respect to the same measure space, dmλ (θ) = (sin θ)2λ dθ. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Deep brain stimulation in Parkinson's disease following fetal nigral transplantation
Authors: Herzog Jan , Pogarell Oliver , Pinsker Marcus O. , Kupsch Andreas , Oertel Wolfgang H. , Lindvall Olle , Deuschl Günther , Volkmann Jens 
Published: June 2008

AbstractOFF‐period dyskinesias have been reported as a consequence of fetal nigral transplantation for Parkinson's disease. This type of dyskinesias may appear in patients even in the prolonged absence of antiparkinson medication and be aggravated by levodopa. Therefore, pharmacological therapeutic approaches in these patients are limited. Here we report two patients with bilateral fetal nigral grafts in the caudate and putamen subjected to deep brain stimulation (DBS) of the globus pallidus internus (GPi) or subthalamic nucleus (STN). Clinical assessment was performed according to UPDRS and the clinical dyskinesia rating scale. In both patients, we found significant improvement in OFF‐period symptoms as well as levodopa‐induced dyskinesias. However, only GPi‐DBS led to a significant reduction of OFF‐period dyskinesias whereas STN‐DBS did not influence dyskinesias unrelated to external dopaminergic application. These findings, based on two case reports, highlight the pivotal role of the GPi in mediating dyskinesia‐related neural activity within the basal ganglia loop. © 2008 Movement Disorder Society
Effective connectivity profile: A structural representation that evidences the relationship between protein structures and sequences
Authors: Bastolla Ugo , Ortíz Angel R. , Porto Markus , Teichert Florian 
Published: June 2008

AbstractThe complexity of protein structures calls for simplified representations of their topology. The simplest possible mathematical description of a protein structure is a one‐dimensional profile representing, for instance, buriedness or secondary structure. This kind of representation has been introduced for studying the sequence to structure relationship, with applications to fold recognition. Here we define the effective connectivity profile (EC), a network theoretical profile that self‐consistently represents the network structure of the protein contact matrix. The EC profile makes mathematically explicit the relationship between protein structure and protein sequence, because it allows predicting the average hydrophobicity profile (HP) and the distributions of amino acids at each site for families of homologous proteins sharing the same structure. In this sense, the EC provides an analytic solution to the statistical inverse folding problem, which consists in finding the statistical properties of the set of sequences compatible with a given structure. We tested these predictions with simulations of the structurally constrained neutral (SCN) model of protein evolution with structure conservation, for single‐ and multi‐domain proteins, and for a wide range of mutation processes, the latter producing sequences with very different hydrophobicity profiles, finding that the EC‐based predictions are accurate even when only one sequence of the family is known. The EC profile is very significantly correlated with the HP for sequence‐structure pairs in the PDB as well. The EC profile generalizes the properties of previously introduced structural profiles to modular proteins such as multidomain chains, and its correlation with the sequence profile is substantially improved with respect to the previously defined profiles, particularly for long proteins. Furthermore, the EC profile has a dynamic interpretation, since the EC components are strongly inversely related with the temperature factors measured in X‐ray experiments, meaning that positions with large EC component are more strongly constrained in their equilibrium dynamics. Last, the EC profile allows to define a natural measure of modularity that correlates with the number of domains composing the protein, suggesting its application for domain decomposition. Finally, we show that structurally similar proteins have similar EC profiles, so that the similarity between aligned EC profiles can be used as a structure similarity measure, a property that we have recently applied for protein structure alignment. The code for computing the EC profile is available upon request writing to ubastolla@cbm.uam.es, and the structural profiles discussed in this article can be downloaded from the SLOTH webserver http://www.fkp.tu‐darmstadt.de/SLOTH/. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Solution structure of the yeast URN1 splicing factor FF domain: Comparative analysis of charge distributions in FF domain structures—FFs and SURPs, two domains with a similar fold
Authors: Bonet Roman , Ramirez‐Espain Ximena , Macias Maria J. 
Published: June 2008

AbstractFF domains are present in three protein families: the splicing factors formin binding protein 11 (FBP11), Prp40, and URN1, the transcription factor CA150, and the p190RhoGTPase‐related proteins. This simplicity in distribution, however, is contrasted by the difficulty in defining their biological role. At best, the group of ligand FF domains can bind to form a motley crew with binding reports pointing also to negative/aromatic sequences, the tetratricopeptide repeat, the transcription factor TFII‐I and even to RNA. To expand our knowledge on the FF domain, we selected the FF domain present in the URN1 yeast splicing factor as the subject for structural studies. The URN1 protein is one of the two known proteins containing only one FF domain, making it the most simplified representative of FF domain‐containing splicing factors. The solution structure reveals that the domain adopts the classical FF fold, with a distinctive negatively charged patch on its surface. All available FF structures have a well‐conserved fold but variable electrostatic patches on their surfaces. These patches are unconserved, even for domains with similar pKas. To investigate potential binding sites in FF domains, we performed structural comparisons to other proteins with similar folds. In addition to the structures detected by SCOP, we included SURP domains, which also adopt the α1‐α2‐310‐α3 architecture. We observed that the main difference between all these structures resides in the orientation of the second helix. Remarkably, in DEK, SURP, and Prp40FF1 structures (the exception is the FBP11FF1 domain), the second helix participates in ligand recognition. Furthermore, SURP and Prp40FF1 binding sites also include the 310 helix, which forms a partially exposed hydrophobic cavity. This cavity is also present in at least CA150FF1 and FF2 structures. Thus, as with WW domains, the FF fold seems to have developed binding‐site variations to accommodate an abundant and variable set of ligands. Proteins 2008. © 2008 Wiley‐Liss, Inc.
Crystal structure of a chimera of human and plasmodium falciparum hypoxanthine guanine phosphoribosyltransferases provides insights into oligomerization
Authors: Gayathri P. , Sujay Subbayya I. N. , Ashok Chethan S. , Selvi T. Senthamizh , Balaram Hemalatha , Murthy M. R. N. 
Published: June 2008

AbstractThe crystal structure of a chimera of Plasmodium falciparum (Pf) and human hypoxanthine guanine phosphoribosyltransferases (HGPRT), which consists of the core of the protein from the human enzyme and the hood region from the Pf enzyme, has been determined as a complex with the product guanosine monophosphate (GMP). The chimera can utilize hypoxanthine, guanine, and xanthine as substrates, similar to the Pf enzyme. It exists as a monomer–dimer mixture in solution, but shifts to a tetramer on addition of phosphoribosyl pyrophosphate (PRPP). The structural studies reveal that the asymmetric unit of the crystal consists of two monomers of the chimeric HGPRT. Surprisingly, the dimer interface of the chimera is the less extensive AC interface of the parent HGPRTs. An analysis of the crystal structures of the various human HGPRTs provides an explanation for the oligomeric characteristics of the chimera. Pro93 and Tyr197 form part of crucial interactions holding together the AB interface in the unliganded or GMP‐bound forms of HGPRT, while Pro93 and His26 interact at the interface after binding of PRPP. Replacement of Tyr197 of human HGPRT by Ile207 in the chimera disrupts the interaction at the AB interface in the absence of PRPP. In the presence of PRPP, the interaction between Pro93 and His26 could restore the AB interface, shifting the chimeric enzyme to a tetrameric state. The structure provides valuable insights into the differences in the AB interface between Pf and human HGPRTs, which may be useful for designing selective inhibitors against the parasite enzyme. Protiens 2008. © 2008 Wiley‐Liss, Inc.
A “couplonic” approach to multilayer magneto‐photonic crystals
Authors: Boucher Y. G. , Bentivegna F. F. L. , Lyubchanskii I. L. 
Published: June 2008

AbstractIn the frame of an exact (non‐perturbative) formulation of the coupled‐mode theory, we describe the non‐reciprocal properties of a one‐dimensional multilayer magneto‐photonic crystal with alternate dielectric and magneto‐optical materials. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Perpendicular anisotropy in Fe/Ag multilayers
Authors: Balogh J. , Fetzer Cs. , Kaptás D. , Kiss L. F. , Szűcs I. S. , Dézsi I. , Vincze I. 
Published: June 2008

AbstractThe direction of the spontaneous magnetization changes from out of plane to in plane at around x = 0.6 in [Ag(2.6 nm)/Fe(x nm)]10 multilayers (0.2 ≤ x ≤ 1) prepared on Si(111) substrate by vacuum evaporation. Transmission Mössbauer spectroscopy measurements of removed samples with a thick capping layer are compared to conversion electron Mössbauer spectroscopy measurements of samples on the Si substrate with a thin capping layer. The stress arising because of the application of a thick capping layer and the removal of the samples from the substrate is shown to have negligible effect on the spontaneous magnetization. The results support that the appearance of the perpendicular anisotropy below x = 0.6 is an intrinsic property of Fe/Ag multilayers. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Low Inflammatory Activation by Self‐Assembling Rosette Nanotubes in Human Calu‐3 Pulmonary Epithelial Cells
Authors: Journeay W. Shane , Suri Sarabjeet S. , Moralez Jesus G. , Fenniri Hicham , Singh Baljit 
Published: June 2008

AbstractRosette nanotubes (RNT) are a new class of metal‐free organic nanotubes synthesized through self‐assembly. Because of the wide range of potential biomedical applications associated with these materials, it is necessary to evaluate their potential in vitro toxicity. Here the cytotoxicity of a lysine‐functionalized nanotube (RNT‐K) in a human Calu‐3 pulmonary epithelial cell line is investigated. The cells were treated with media only (control), lysine (50 mg mL−1), RNT‐K (1, 5, and 50 µg mL−1), Min‐U‐Sil quartz microparticles (QM; 80 µg mL−1), and lipopolysaccharide (LPS; 1 µg mL−1). The supernatants were analyzed at 1, 6, and 24 h after treatment for the expression of three proinflammatory mediators: IL‐8, TNF‐α and EMAP‐II. Cellular viability determined with the Trypan blue assay is significantly reduced in the QM and high‐dose RNT‐treated groups. TNF‐α and EMAP‐II are undetectable by enzyme‐linked‐immunosorbent assay (ELISA) in the supernatant of all groups. Although IL‐8 concentrations do not differ between treatments, its concentrations increase with time within each of the groups. Quantitative reverse‐transcriptase polymerase chain reaction (qRTPCR) of IL‐8 mRNA shows increased expression in the high‐dose RNT‐treated groups at both 1 and 6 h, while an adhesion molecule, ICAM‐1 mRNA, shows the greatest increase at 6 h in the QM‐treated group. In summary, RNT‐K neither reduces cell viability at moderate doses nor does it induce a time‐dependent inflammatory response in pulmonary epithelial cells in vitro.
Fast analysis of rapeseed glucosinolates by near infrared reflectance spectroscopy
Authors: Biston R. , Dardenne P. , Cwikowski M. , Marlier M. , Severin M. , Wathelet J‐P. 
Published: June 2008

AbstractIndustry and plant breeders require fast methods to analyze glucosinolates in rapeseed. We tested the potential of near infrared reflectance spectroscopy (NIRS) for this analysis and developed calibration equations on a large population of whole seeds. Reference methods used are high performance liquid chromatography (HPLC) and gas liquid chromatography (GLC) of desulphoglucosinolates, a glucose‐release method after purification on an anion exchange column and a palladium test. In the range from 2 to 107 μM/g and after transformation of the data in first derivative, a correlation coefficient of 0.99 was observed, as well as standard errors of estimated values of 2.15, 2.52, 2.67 and 4.07 for samples analyzed by HPLC, GLC, glucose and the palladium test, respectively. With different wavelengths, a limited calibration test on seeds containing from 4 to 40 μM/g gives a standard error of 1.91 μM/g (HPLC).
Mathematical simulation of an oilseed press
Authors: Vadke Vivek S. , Sosulski F. W. , Shook C. A. 
Published: June 2008

AbstractA mathematical model of an oilseed press was developed by superimposition of filtration analysis on screw extrusion theory to calculate press throughput and residual oil content in presscake for a given press geometry and physical properties of oilseed. The model predicted that press performance would improve, i.e., the throughput would increase and residual oil would decrease, if the press were cooled during operation. Longer presses would also give higher throughputs with lower residual oil contents. The predicted effects of changes in shaft speed and choke opening on press performance agreed reasonably well with experimental results obtained on a small laboratory press. A relatively large error of 9.0% in the prediction of throughput could be attributed to changes in viscosity of oilseed mass occurring during its passage through the press. It is expected that use of ‘expression’ analysis in place of the simple filtration analysis would improve the predictive ability of the model.