julilili42/papers huggingface dataset:
One-Pot Synthesis of 4,6-Diaryl-2-oxo(imino)-1,2-dihydropyridine-3-carbonitrile; a New Scaffold for p38α MAP Kinase Inhibition
2010-06-02

Two series of new compounds with the general formula 4,6-diaryl-2-oxo-1,2-dihydropyridine-3-carbonitriles and their isosteric 2-imino derivatives were synthesized by the multicomponent reaction of the appropriate acetophenone, aromatic aldehyde, ammonium acetate, and malononitrile or ethyl cyanoacetate. The products were obtained with excellent yields. The prepared compounds were evaluated for their in vitro ability to inhibit p38 alpha-MAP kinase. Several compounds showed p38 MAP kinase inhibitory properties with IC(50) as low as 0.07 microM. This is the first time to report compounds with such scaffold as p38 alpha-MAP kinase inhibitors. This asserts the potentiality of multicomponent reactions in drug discovery.
Gauge invariance and vacuum energies of non-Abelian string-configurations
2010-06-02

We improve on a method to compute the fermion contribution to the vacuum\\npolarization energy of string-like configurations in a non-Abelian gauge\\ntheory. We establish the new method by numerically verifying the invariance\\nunder (a subset of) local gauge transformations. This also provides further\\nsupport for the use of spectral methods to compute vacuum polarization energies\\nin general. We confirm that the vacuum energy in the MS-bar renormalization\\nscheme is tiny as compared to the mass of the fluctuating fermion field.\\nNumerical results for the physical on-shell scheme are also presented.\\n
Natural Staphylococcus aureus ‐derived peptidoglycan fragments activate NOD2 and act as potent costimulators of the innate immune system exclusively in the presence of TLR signals
2010-06-03

ABSTRACT Innate immune sensing of Staphylococcus aureus unravels basic mechanisms leading to either effective antibacterial immune responses or harmful inflammation. The nature and properties of S. aureus ‐derived pathogen‐associated molecular pattern (PAMPs) are still not completely understood. We investigated the innate immune sensing of peptidoglycan (PGN) structures and subsequent immune consequences. Macromolecular PGN (PGN polymer ) preparations activated NF‐κB through human Toll‐like receptors 2 (TLR2), as shown by luciferase reporter assays, and induced murine dendritic cell (DC) maturation and cytokine production. In contrast, PGN polymer from lgt ‐mutant S. aureus failed to stimulate human TLR2, demonstrating that lipoproteins within the macromolecular structures of PGN polymer , but not PGN itself, activate TLR2. Thus, HPLC‐purified monomeric PGN (PGN monomer ) structures were investigated. Strikingly, PGN monomer completely lacked NF‐κB activation, lacked TLR2 activity, and failed to functionally activate murine DCs. However, PGN monomer in concert with various TLR ligands most effectively stimulated DCs to up‐regulate IL‐12p70 and IL‐23 by ≥3‐ to 5‐fold. Consequently, DCs coactivated by PGN monomer markedly up‐regulated Th1 and Th17 while suppressing Th2 cell priming. Notably, PGN monomer failed to coactivate NOD2 −/− DCs. This demonstrates that PGN monomer is a natural ligand of NOD2, which was previously only demonstrated for synthetic compounds like muramyl dipeptide. Interestingly, murine DCs lacking TLR2 remained mute in response to the combinative immune sensing of S. aureus ‐derived PAMPs, including PGN monomer , providing for the first time an explanation of why S. aureus can colonize the nasal mucosa in the absence of inflammation. This is very likely based on the lack of TLR2 expression in mucosal epithelial cells under normal conditions, which determines the unresponsiveness to S. aureus PAMPs.—Volz, T., Nega, M., Buschmann, J., Kaesler, S., Guenova, E., Peschel, A., Röcken, M., Götz, F., Biedermann, T. Natural Staphylococcus aureus ‐derived peptidoglycan fragments activate NOD2 and act as potent costimulator of the innate immune system exclusively in the presence of TLR signals. FASEB J. 24, 4089–4102 (2010). www.fasebj.org
The Trigonal Prismatic Cluster Compound W6CCl15 and a Carambolage of Tungsten Clusters in the Structure of the Heteroleptic Cluster Compound W30C2(Cl,Br)68
2010-06-03

Reactions between W(6)Cl(12) and carbon halides can initiate a cascade of reactions and reaction products, yielding W(6)Cl(18), W(6)CCl(18), and W(6)CCl(15) with increasing temperature, before decomposition into tungsten carbide is obtained. The new compound W(6)CCl(15) and the new heteroleptic compound W(30)C(2)(Cl,Br)(68) obtained from these reactions were structurally characterized. The structure of W(30)C(2)X(68) combines a carambolage of two distinct octahedral and one centered trigonal prismatic cluster in one structure as refined by X-ray single-crystal diffraction (P1, Z = 1; a = 12.003(2) A, b = 14.862(3) A, c = 15.792(3) A, alpha = 88.75(2) degrees, beta = 68.85(2) degrees, gamma = 71.19(2) degrees). The unit cell content W(30)C(2)X(68) accommodates five hexanuclear tungsten clusters, similar by a total of three octahedral [W(6)X(8)] type clusters and two carbon-centered trigonal prismatic [W(6)CX(12)] type clusters, sharing terminal halogen atoms to form a network structure. The trigonal prismatic cluster compound W(6)CCl(15) (P2(1)/c, Z = 4; a = 9.8830(4) A, b = 11.8945(4) A, c = 17.8670(7) A, beta = 107.883(2) degrees) is related to the already known compound W(6)CCl(16). According to X-ray powder structure refinement, the structure is showing a special connectivity pattern with short intercluster W-W contacts between trigonal prismatic cluster units.
Identification of Carbonate-Rich Outcrops on Mars by the Spirit Rover
2010-06-04

Ancient Carbonate Minerals on Mars The historical presence of liquid water on Mars together with a CO 2 -rich atmosphere should have resulted in the accumulation of large deposits of carbonate minerals. Yet, evidence for the presence of carbonates on the surface of Mars has been scarce. Using data collected by the Mars Exploration Rover, Spirit, Morris et al. (p. 421 , published online 3 June; see the Perspective by Harvey ) now present evidence for carbonate-rich outcrops in the Comanche outcrops within the Gusev crater. The carbonate is a major outcrop component and may have formed in the Noachian era (∼4 billion years ago) by precipitation from hydrothermal solutions that passed through buried carbonate deposits. Thus, it is likely that extensive aqueous activity under neutral pH conditions did occur on Mars.
No association between variation in the NR4A1 gene locus and metabolic traits in white subjects at increased risk for type 2 diabetes
2010-06-04

Abstract Background The nuclear receptor NR4A1 is implicated in metabolic regulation in insulin-sensitive tissues, such as liver, adipose tissue, and skeletal muscle. Functional loss of NR4A1 results in insulin resistance and enhanced intramuscular and hepatic lipid content. Therefore, we investigated in a cohort of white European subjects at increased risk for type 2 diabetes whether genetic variation within the NR4A1 gene locus contributes to prediabetic phenotypes, such as insulin resistance, ectopic fat distribution, or β-cell dysfunction. Methods We genotyped 1495 subjects (989 women, 506 men) for five single nucleotide polymorphisms (SNPs) tagging 100% of common variants (MAF = 0.05) within the NR4A1 gene locus with an r 2 = 0.8. All subjects underwent an oral glucose tolerance test (OGTT), a subset additionally had a hyperinsulinemic-euglycemic clamp (n = 506). Ectopic hepatic (n = 296) and intramyocellular (n = 264) lipids were determined by magnetic resonance spectroscopy. Peak aerobic capacity, a surrogate parameter for oxidative capacity of skeletal muscle, was measured by an incremental exercise test on a motorized treadmill (n = 270). Results After appropriate adjustment and Bonferroni correction for multiple comparisons, none of the five SNPs was reliably associated with insulin sensitivity, ectopic fat distribution, peak aerobic capacity, or indices of insulin secretion (all p ≥ 0.05). Conclusions Our data suggest that common genetic variation within the NR4A1 gene locus may not play a major role in the development of prediabetic phenotypes in our white European population.
Statistical Parsing of Morphologically Rich Languages (SPMRL) What, How and Whither
2010-06-05

The term Morphologically Rich Languages (MRLs) refers to languages in which significant information concerning syntactic units and relations is expressed at word-level. There is ample evidence that the application of readily available statistical parsing models to such languages is susceptible to serious performance degradation. The first workshop on statistical parsing of MRLs hosts a variety of contributions which show that despite language-specific idiosyncrasies, the problems associated with parsing MRLs cut across languages and parsing frameworks. In this paper we review the current state-of-affairs with respect to parsing MRLs and point out central challenges. We synthesize the contributions of researchers working on parsing Arabic, Basque, French, German, Hebrew, Hindi and Korean to point out shared solutions across languages. The overarching analysis suggests itself as a source of directions for future investigations.
Enhancing Authentic Web Pages for Language Learners
2010-06-05

Second language acquisition research since the 90s has emphasized the importance of supporting awareness of language categories and forms, and input enhancement techniques have been proposed to make target language features more salient for the learner. We present an NLP architecture and webbased implementation providing automatic visual input enhancement for web pages. Learners freely choose the web pages they want to read and the system displays an enhanced version of the pages. The current system supports visual input enhancement for several language patterns known to be problematic for English language learners, as well as fill-in-the-blank and clickable versions of such pages supporting some learner interaction. 1
Contribution of SMC (Structural Maintenance of Chromosomes) and SpoIIIE to Chromosome Segregation in Staphylococci
2010-06-05

ABSTRACT In contrast to rod-shaped bacteria, little is known about chromosomal maintenance and segregation in the spherical Staphylococcus aureus . The analysis of chromosomal segregation in smc (structural maintenance of chromosomes) and spoIIIE single and double mutants unravels differences in the chromosome dynamics in the spherical staphylococcal cells compared to the model in rods.
A pragmatist theory of capitalism
2010-06-05

This article explores the potential of pragmatist social theory (Dewey and Mead) for elaborating and clarifying the classical analyses of capitalism by Marx, Schumpeter, Sombart and Weber. It shows how a reinterpretation in the context of pragmatist discourse can overcome the rationalist shortcomings of Weber's theory of capitalism and formulate key Marxist concepts like 'capital' or 'reification' more convincingly. It also outlines a multi-level approach for analysing the dynamics of capitalism, focusing on the interaction between class structures, individual creativity and the communication of innovative paradigms.
Emotional Perception of Fairy Tales: Achieving Agreement in Emotion Annotation of Text
2010-06-05

Emotion analysis (EA) is a rapidly developing area in computational linguistics. An EA system can be extremely useful in fields such as information retrieval and emotion-driven computer animation. For most EA systems, the number of emotion classes is very limited and the text units the classes are assigned to are discrete and predefined. The question we address in this paper is whether the set of emotion categories can be enriched and whether the units to which the categories are assigned can be more flexibly defined. We present an experiment showing how an annotation task can be set up so that untrained participants can perform emotion analysis with high agreement even when not restricted to a predetermined annotation unit and using a rich set of emotion categories. As such it sets the stage for the development of more complex EA systems which are closer to the actual human emotional perception of text.
Direct Parsing of Discontinuous Constituents in German
2010-06-05

Discontinuities occur especially frequently in languages with a relatively free word order, such as German. Generally, due to the longdistance dependencies they induce, they lie beyond the expressivity of Probabilistic CFG, i.e., they cannot be directly reconstructed by a PCFG parser. In this paper, we use a parser for Probabilistic Linear Context-Free Rewriting Systems (PLCFRS), a formalism with high expressivity, to directly parse the German NeGra and TIGER treebanks. In both treebanks, discontinuities are annotated with crossing branches. Based on an evaluation using different metrics, we show that an output quality can be achieved which is comparable to the output quality of PCFG-based systems. In most constituency treebanks, sentence annotation is restricted to having the shape of trees without crossing branches, and the non-local dependencies induced by the discontinuities are modeled by an additional mechanism. In the Penn Treebank (PTB) (Marcus et al., 1994), e.g., this mechanism is a combination of special labels and empty nodes, establishing implicit additional edges. In the German TüBa-D/Z (Telljohann et al., 2006), additional edges are established by a combination of topological field annotation and special edge labels. As an example, Fig. 1 shows a tree from TüBa-D/Z with the annotation of (1). Note here the edge label ON-MOD on the relative clause which indicates that the subject of the sentence (alle Attribute) is modified. 1
Septal and lateral wall localization of PBP5, the major D,D‐carboxypeptidase of Escherichia coli, requires substrate recognition and membrane attachment
2010-06-07

Summary The distribution of PBP5, the major D,D‐carboxypeptidase in Escherichia coli , was mapped by immunolabelling and by visualization of GFP fusion proteins in wild‐type cells and in mutants lacking one or more D,D‐carboxypeptidases. In addition to being scattered around the lateral envelope, PBP5 was also concentrated at nascent division sites prior to visible constriction. Inhibiting PBP2 activity (which eliminates wall elongation) shifted PBP5 to midcell, whereas inhibiting PBP3 (which aborts divisome invagination) led to the creation of PBP5 rings at positions of preseptal wall formation, implying that PBP5 localizes to areas of ongoing peptidoglycan synthesis. A PBP5(S44G) active site mutant was more evenly dispersed, indicating that localization required enzyme activity and the availability of pentapeptide substrates. Both the membrane bound and soluble forms of PBP5 converted pentapeptides to tetrapeptides in vitro and in vivo , and the enzymes accepted the same range of substrates, including sacculi, Lipid II, muropeptides and artificial substrates. However, only the membrane‐bound form localized to the developing septum and restored wild‐type rod morphology to shape defective mutants, suggesting that the two events are related. The results indicate that PBP5 localization to sites of ongoing peptidoglycan synthesis is substrate dependent and requires membrane attachment.
VHEγ-ray emission of PKS 2155–304: spectral and temporal variability
2010-06-07

Observations of very high energy gamma-rays from blazars provide information\\nabout acceleration mechanisms occurring in their innermost regions. Studies of\\nvariability in these objects allow a better understanding of the mechanisms at\\nplay. To investigate the spectral and temporal variability of VHE (&gt;100 GeV)\\ngamma-rays of the well-known high-frequency-peaked BL Lac object PKS 2155-304\\nwith the H.E.S.S. imaging atmospheric Cherenkov telescopes over a wide range of\\nflux states. Data collected from 2005 to 2007 are analyzed. Spectra are derived\\non time scales ranging from 3 years to 4 minutes. Light curve variability is\\nstudied through doubling timescales and structure functions, and is compared\\nwith red noise process simulations. The source is found to be in a low state\\nfrom 2005 to 2007, except for a set of exceptional flares which occurred in\\nJuly 2006. The quiescent state of the source is characterized by an associated\\nmean flux level of 4.32 +/-0.09 x 10^-11 cm^-2 s^-1 above 200 GeV, or\\napproximately 15% of the Crab Nebula, and a power law photon index of 3.53\\n+/-0.06. During the flares of July 2006, doubling timescales of ~2 min are\\nfound. The spectral index variation is examined over two orders of magnitude in\\nflux, yielding different behaviour at low and high fluxes,which is a new\\nphenomenon in VHE gamma-ray emitting blazars. The variability amplitude\\ncharacterized by the fractional r.m.s. is strongly energy-dependent and is\\nproportional to E^(0.19 +/- 0.01). The light curve r.m.s. correlates with the\\nflux. This is the signature of a multiplicative process which can be accounted\\nfor as a red noise with a Fourier index of ~2. This unique data set shows\\nevidence for a low level gamma-ray emission state from PKS 2155-304, which\\npossibly has a different origin than the outbursts. The discovery of the light\\ncurve lognormal behaviour might be an indicator ..\\n
Bimodal pollination system of the bromeliad Aechmea nudicaulis involving hummingbirds and bees
2010-06-07

Abstract In order to compare the effectiveness of birds and insects as pollinators, we studied the floral biology of the bromeliad Aechmea nudicaulis (L.) Grisebach in the biome of the Atlantic rain forest, southern Brazil. On Santa Catarina Island, flowering extends from mid‐September to the end of December, with diurnal anthesis. The reproductive system is obligatory xenogamy, thus pollinator‐dependent. Flowers secrete 31.84 μl of nectar per day, with a mean sugar concentration of 23.2%. Highest nectar volume and sugar concentration occur at the beginning of anthesis. Most floral traits are characteristic for ornithophily, and nectar production appears to be adapted to the energy demand of hummingbirds. Continued secretion of the sucrose‐dominated nectar attracts and binds visitors to inflorescences, strengthening trapline foraging behaviour. Experiments assessing seed set after single flower visits were performed with the most frequent visitors, revealing the hummingbird Thalurania glaucopis as the most effective pollen vector. In addition, bees are also functional pollinators, as substantiated by their high visitation frequency. We conclude that this pollination system is bimodal. Thus, there is redundancy in the pollination service provided by birds and bees, granting a high probability of successful reproduction in Ae. nudicaulis .
Charge Separation at Molecular Donor–Acceptor Interfaces: Correlation Between Morphology and Solar Cell Performance
2010-06-07

Blends of organic electron and hole conductive materials are widely used for ambipolar charge-carrier transport and donor/acceptor (DA) photovoltaic cells. Thereby, the efficiency of these excitonic solar cells is correlated to the morphology of the interface between the donor and the acceptor materials, which in turns depends on the preparation conditions, the crystallization of the particular materials, and the interaction between the donor and acceptor molecules. In this contribution, the influence of the morphology on the solar cell architecture and performance will be discussed using different molecular DA combinations.
Neuroprotection by acetoacetate and β-hydroxybutyrate against NMDA-induced RGC damage in rat—possible involvement of kynurenic acid
2010-06-07

ACA and BHB had a significant dose-dependent neuroprotective effect on RGC in a rat model of NMDA-induced RGC damage. Both ketone bodies also significantly attenuated NMDA-induced reduction of retinal KYNA production in vitro, suggesting that this mechanism may be essential for the neuroprotective effects of ACA and BHB in vivo. Our results imply that ketone bodies may represent an additional treatment option in chronic neurodegenerative disorders of the eye.
A Comparison of Similarity Measures for Localization with Passive RFID Fingerprints
2010-06-07

We present a novel approach to self-localization with passive RFID fingerprints using vector space similarity measures and weighted k-nearest neighbors (WKNN). Embedded in a particle filter, our technique provides robust and accurate position estimates. This is shown through various experiments with a mobile robot. The formulation of the observation model guarantees applicability to any type of off-the-shelf RFID reader which counts RFID tag detections. Different similarity measures are investigated, and a new measure is proposed.
Working and Training Conditions of Residents in Pediatric Surgery: A Nationwide Survey in Germany
2010-06-07

Trainee satisfaction with regulations on working hours is low. Despite a general satisfaction with all fields appraised, improvements in various individual areas, e. g., the attitude of departmental heads and strategies of career development, are necessary.
A Comparison of Efficient Global Image Features for Localizing Small Mobile Robots
2010-06-07

Global image features are well-suited for the visual self-localization of mobile robots. They are fast to compute, to compare and do not require much storage space. Especially when using small mobile robots with limited processing capabilities and low-resolution cameras, global features can be preferred to local features. In this paper, we compare the accuracy and computation times of different global image features when localizing small mobile robots. We test the methods under realistic conditions, taking illumination changes and translations into account. By employing a particle filter and reducing the image resolution, we speed up the localization process considerably. 1
Quantitative sensory testing in the German Research Network on Neuropathic Pain (DFNS): Somatosensory abnormalities in 1236 patients with different neuropathic pain syndromes
2010-06-08

Neuropathic pain is accompanied by both positive and negative sensory signs. To explore the spectrum of sensory abnormalities, 1236 patients with a clinical diagnosis of neuropathic pain were assessed by quantitative sensory testing (QST) following the protocol of DFNS (German Research Network on Neuropathic Pain), using both thermal and mechanical nociceptive as well as non-nociceptive stimuli. Data distributions showed a systematic shift to hyperalgesia for nociceptive, and to hypoesthesia for non-nociceptive parameters. Across all parameters, 92% of the patients presented at least one abnormality. Thermosensory or mechanical hypoesthesia (up to 41%) was more frequent than hypoalgesia (up to 18% for mechanical stimuli). Mechanical hyperalgesias occurred more often (blunt pressure: 36%, pinprick: 29%) than thermal hyperalgesias (cold: 19%, heat: 24%), dynamic mechanical allodynia (20%), paradoxical heat sensations (18%) or enhanced wind-up (13%). Hyperesthesia was less than 5%. Every single sensory abnormality occurred in each neurological syndrome, but with different frequencies: thermal and mechanical hyperalgesias were most frequent in complex regional pain syndrome and peripheral nerve injury, allodynia in postherpetic neuralgia. In postherpetic neuralgia and in central pain, subgroups showed either mechanical hyperalgesia or mechanical hypoalgesia. The most frequent combinations of gain and loss were mixed thermal/mechanical loss without hyperalgesia (central pain and polyneuropathy), mixed loss with mechanical hyperalgesia in peripheral neuropathies, mechanical hyperalgesia without any loss in trigeminal neuralgia. Thus, somatosensory profiles with different combinations of loss and gain are shared across the major neuropathic pain syndromes. The characterization of underlying mechanisms will be needed to make a mechanism-based classification feasible.