julilili42/papers huggingface dataset:
Modelling day‐ahead electricity prices
2003-06-01

A production-based approach is introduced to take into account different attitudes and liabilities of market participants to discuss the equilibrium day-ahead prices on electricity. Conditions ensuring the existence of the equilibrium are given and price distribution is considered. A discussion of reasons for high price volatility is given.
Appearance-based Tracking of Persons with an Omnidirectional Vision Sensor
2003-06-01

This paper addresses the problem of tracking a moving person with a single, omnidirectional camera. An appearance-based tracking system is described which uses a self-acquired appearance model and a Kalman filter to estimate the position of the person. Features corresponding to ``depth cues'' are first extracted from the panoramic images, then an artificial neural network is trained to estimate the distance of the person from the camera. The estimates are combined using a discrete Kalman filter to track the position of the person over time. The ground truth information required for training the neural network and the experimental analysis was obtained from another vision system, which uses multiple webcams and triangulation to calculate the true position of the person. Experimental results show that the tracking system is accurate and reliable, and that its performance can be further improved by learning multiple, person-specific appearance models
Emotional after‐effects on the P3 component of the event‐related brain potential
2003-06-01

Agrowing body of literature indicates that affective states can influence cognitive processes. The core assumption of Ellis and Ashbrook's (1988) model explaining these emotional after‐effects on cognition is that the emotional state regulates the allocation of processing resources. A negative emotional state is supposed to pre‐empt capacity normally allocated to the cognitive task at hand. This is assumed to occur because the negative emotional state leads to an increase in intrusive, irrelevant thoughts, which compete with relevant cognitive activities and thus result in a lack of attention given to relevant features of the task to be performed. In the present study, the hypothesis that negative emotions lead to a reduced information‐processing capacity and that this is observable on a very basic level of information processing is tested. Therefore, 102 participants were assigned to three independent groups, each inducing one of a negative, a positive, or a neutral mood by means of a 3‐minute video‐clip. Shortly after the video‐clip, two acoustical stimuli with increasing information were presented, while the P3 component of the event‐related brain potential on these stimuli was measured as a psychophysiological indicator of cognitive resource allocation. In addition, the expenmental manipulation was checked by assessing subjective and external mood ratings as well as cortical alpha activity. Results show that the videos did in fact induce positive, neutral, or negative mood. Moreover, even when controlling for video‐related unspecific cortical arousal, a significant emotional after‐effect was found on the P3 component of the event‐related brain potential, indicating reduced information‐processing capacity, particularly in the negative mood condition. The reported data support Ellis and Ashbrook's model of emotional after‐effects on cognitive processes. As those effects were observable after an event that did not demand a high amount of cognitive resources, this suggests that even tasks that do not heavily engage central processing resources and are not likely to be influenced by cognitive strategies, seem to be affected by a negative emotional state.
A visual and interactive tool for optimizing lexical postcorrection of OCR results
2003-06-01

Systems for postcorrection of OCR-results can be fine tuned and adapted to new recognition tasks in many respects. One issue is the selection and adaption of a suitable background dictionary. Another issue is the choice of a correction model, which includes, among other decisions, the selection of an appropriate distance measure for strings and the choice of a scoring function for ranking distinct correction alternatives. When combining the results obtained from distinct OCR engines, further parameters have to be fixed. Due to all these degrees of freedom, adaption and fine tuning of systems for lexical postcorrection is a difficult process. Here we describe a visual and interactive tool that semi-automates the generation of ground truth data, partially automates adjustment of parameters, yields active support for error analysis and thus helps to find correction strategies that lead to high accuracy with realistic effort.
Microwave properties of MgB/sub 2/ thin films
2003-06-01

The microwave surface impedance Z/sub s/=R/sub s/+j/spl omega//spl mu//sub 0//spl lambda/ of MgB/sub 2/ thin films was measured via advanced dielectric resonator (DR) techniques. First, the temperature dependence of the penetration depth /spl lambda/ measured with a sapphire puck at 17.9 GHz can be well fitted from 5 K close to T/sub c/ by the standard BCS integral expression assuming the reduced energy gap /spl Delta/(0)/kT/sub c/ to be as low as 1.0-1.1 assuming /spl lambda/(0)=100--110 nm. These results clearly indicate the s-wave nature of the order parameter. Similar good fits were achieved by an anisotropic one gap and an isotropic two-gap model. Second, the temperature dependence of surface resistance R/sub s/, as measured with a rutile puck, indicates an exponential behavior below about T/sub c//2 with a reduced energy gap being consistent with the one determined from the /spl lambda/ data. The R/sub s/ value at 4.2 K was found to be as low as 19 /spl mu//spl Omega/ at 7.2 GHz, which is comparable with that of a high-quality high temperature thin films of YBa/sub 2/Cu/sub 3/O/sub 7/. A higher-order mode at 17.9 GHz was employed to investigate the frequency f dependence of R/sub s//spl alpha/f/sup n(T)/. Our results revealed an decrease of n with increasing temperature ranging from n=2 below 8 K to n=1 close to T/sub c/. Finally, the microwave power handling of MgB/sub 2/ films was deduced and compared with values for YBa/sub 2/Cu/sub 3/O/sub 7/ films. We found that the power handling of MgB/sub 2/ is comparable or even better than that of YBa/sub 2/Cu/sub 3/O/sub 7/ films for temperature below 30 K.
Patient selection for incus body coupling of a totally implantable middle ear implant
2003-06-01

In selected cases, IBC of the TI-MEI investigated herein may be indicated for the treatment of SNHL, provided the following four conditions are met. First, the patient does not derive sufficient benefit from conventional HAs. Second, the specific indication for IBC is restricted to situations that do not allow the coupling of the MEI to the long incus process (e.g. due to an anatomical variation of facial nerve location). Third, IBC is restricted to patients with a steeply sloped moderate to severe high frequency SNHL, amounting to 90 dB HL from 3 to 8 kHz. Patients with low frequency SNHL should not be operated on with the IBC technique, as maximum low frequency hearing loss at 0.5 kHz must not exceed 30 dB. Fourth, Schueller's X-ray should reveal normal mastoid pneumatization. Being restricted to a 6-month follow-up period, this paper provides early clinical results and no clinical evidence of long-term efficiency of the implant.
A model for speed adaptation of individuals and existence of weak solutions
2003-06-01

When individuals move together in large groups, as seen in schools of fish, they adapt their speed and direction to that of their neighbours. We present and analyse a model for the speed adaptation process in the case in which all individuals move in the same or in two opposite directions. The model consists of a hyperbolic conservation law for the density of individuals coupled to a parabolic or elliptic equation for speed. A detailed linear analysis reveals several mechanisms for the appearance of instabilities of the homogeneous steady state, which trigger the formation of schools, herds, flocks, etc. Long-term existence of weak solutions is shown using the vanishing viscosity approach.
Protein kinase C‐α attenuates cholinergically stimulated gastric acid secretion of rabbit parietal cells
2003-06-01

The phorbolester 12‐ O ‐tetradecanoyl phorbol‐13‐acetate (TPA), an activator of protein kinase C (PKC), inhibits cholinergic stimulation of gastric acid secretion. We observed that this effect strongly correlated with the inhibition of Ca 2+ /calmodulin‐dependent protein kinase II (CaMKII) activity in rabbit parietal cells. The aim of this study was to specify the function of PKC‐ α in cholinergically stimulated H + secretion. PKC‐ α represents the only calcium‐dependent PKC isoenzyme that has been detected in rabbit parietal cells. Gö 6976, an inhibitor of calcium‐dependent PKC, concentration‐dependently antagonized the inhibitory effect of TPA, and, therefore, revealed the action of PKC‐ α on carbachol‐induced acid secretion in rabbit parietal cells. TPA exerted no additive inhibition of carbachol‐stimulated acid secretion if acid secretion was partially inhibited by the potent CaMKII inhibitor 1‐[ N , O ‐bis(5‐isoquinolinsulfonyl)‐ N ‐methyl‐ L ‐tyrosyl]‐4‐phenyl‐piperazine (KN‐62). Since both kinase modulators, TPA and KN‐62, affected no divergent signal transduction pathways in the parietal cell, an in vitro model has been used to study if PKC directly targets CaMKII. CaMKII purified from parietal cell‐containing gastric mucosa of pig, was transphosphorylated by purified cPKC containing PKC‐ α up to 1.8 mol P i per mol CaMKII in vitro . The autonomy site of CaMKII was not transphosphorylated by PKC. The phosphotransferase activity of the purified CaMKII was in vitro inhibited after transphosphorylation by PKC if calmodulin was absent during transphosphorylation. Attenuation of CaMKII activity by PKC showed strong similarity to the downregulation of CaMKII by basal autophosphorylation. Our results suggest that PKC‐ α and CaMKII are closely functionally linked in a cholinergically induced signalling pathway in rabbit parietal cells. We assume that in cholinergically stimulated parietal cells PKC‐ α transinhibits CaMKII activity, resulting in an attenuation of acid secretion. British Journal of Pharmacology (2003) 139 , 545–554. doi: 10.1038/sj.bjp.0705211
Spectral Mapping Theorems For Evolution Semigroups on Spaces of Almost Periodic Functions
2003-06-01

. We show that the weak spectral mapping theorem holds for evolution semigroups on spaces of periodic functions. Furthermore, we prove the spectral mapping theorem for evolution semigroups on spaces of (weakly asymptotically) almost periodic functions. The results are applied to the study of hyperbolic periodic and (weakly asymptotically) almost periodic evolution families U = {U (t, s) : t ≥ s}. We establish conditions on U which lead to unique periodic resp. (weakly asymptotically) almost periodic mild solutions u (t) = U (t, s) u (s) + f t s U (t, τ)f (τ) dτ, t ≥ s ∊ R, provided that f is periodic resp. (weakly asymptotically) almost periodic with relatively compact range.
A Limit Relation between Black Hole Mass and H Width: Testing Super-Eddington Accretion in Active Galactic Nuclei
2003-06-01

(abbreviated) We show that there is a limit relation between the black hole mass and the width at the half maximum of H for active galactic nuclei (AGNs) with super-Eddington accretion rates. When a black hole has a super-Eddington accretion rate, the empirical relation of reverberation mapping has two possible ways. First, it reduces to a relation between the black hole mass and the size of the broad line region due to the photon trapping effects inside the accretion disk. For the Kaspi et al.'s empirical reverberation relation, we get the limit relation as , called as the Eddington limit. Second, the Eddington limit luminosity will be relaxed if the trapped photons can escape from the magnetized super-Eddington accretion disk via the photon bubble instability, and the size of the broad line region will be enlarged according to the empirical reverberation relation, leading to a relatively narrow width of H . We call this the Begelman limit. Super-Eddington accretions in a sample composed of 164 AGNs have been searched by this limit relation. We find there are a handful of objects locate between the Eddington and Begelman limit lines, they may be candidates of super-Eddington accretors in a hybrid structure of photon trapping and photon bubble instability. The maximum width of H is in the reange of km s for the maximum mass black holes with super-Eddington accretion rates among AGNs. We suggest that this limit relation is more reliable and convenient to test whether a source is super-Eddington and useful to probe the structure of the super-Eddington accretion process.
Regulatory effects of IL‐12 and IL‐18 on Onchocerca volvulus‐ and Entamoeba histolytica‐specific cellular reactivity and cytokine profiles
2003-06-01

SUMMARY In the present study, the cytokines interleukin (IL)‐12 and IL‐18 were evaluated for their capacity to modulate and to re‐direct in vitro parasite antigen‐specific cellular responsiveness in patients exposed to Onchocerca volvulus and Entamoeba histolytica infection. We found that IL‐18 was highly capable of reducing parasite antigen‐induced IL‐10 production by PBMC. In contrast, addition or neutralization of IL‐12, also in combination with IL‐18 and the interferon‐γ‐inducible chemokine IP‐10 did not affect IL‐10 production. Interestingly, the highest IL‐10 levels were measured when IL‐18 and IP‐10 were both neutralized. Although having no effect on IL‐10, IL‐12 strongly promoted spontaneous and parasite antigen‐driven IFN‐γ production by PBMC, whereas IL‐18 was only moderately affecting IFN‐γ release by PBMC re‐stimulated with E. histolytica ‐ or O. volvulus ‐specific antigens. Both IL‐12 and IL‐18 diminished the cellular production of IL‐13, and a synergistic effect was observed when the cytokines were combined. Likewise, neutralization of IL‐12 enhanced Entamoeba and Onchocerca antigen‐driven IL‐13 production, but no further increase of IL‐13 was observed, when anti‐IL‐12 and anti‐IL‐18 were used together. This study disclosed that IL‐18 will significantly down‐regulate parasite‐specific IL‐10 production, whereas IL‐12 induced IFN‐γ and inhibited IL‐13 production by PBMC from humans exposed to O. volvulus and E. histolytica. Such selective immune‐regulatory capacity of IL‐12 and IL‐18 may comprise an important tool to re‐direct polarized cytokine responses towards a balanced Th1/Th2 cytokine profile, which may prevent pathology and promote immunity against helminth and protozoan parasite infections.
Synthesis and 5‐HT2A Radioligand Receptor Binding Assays of DOMCl and DOMOM, Two Novel 5‐HT2A Receptor Ligands
2003-06-01

Abstract A synthesis of two new active substances, DOMCl (1‐(4‐chloromethyl‐2, 5‐dimethoxyphenyl)‐2‐propanamine; 2 ) and DOMOM (1‐(2, 5‐dimethoxy‐4‐methoxymethylphenyl)‐2‐propanamine; 3 ), was developed. Unexpectedly, the Blanc reaction permitted successful synthesis of 2, 5‐dimethoxyphenylpropylamine derivatives having a substituted methyl group in position 4 since solvation of the reactant occurs during the reaction. Afterwards, their affinities towards the 5‐HT 2A receptor were examined in 5‐HT 2A radioligand receptor binding assays. The study of these substances is of considerable interest because they were predicted, by preliminary molecular modeling studies based on mescalin units, to be potential new hallucinogens that should be added to the list of substances prohibited by law. It was assumed that DOMCl would be 82 times more potent as a hallucinogen than mescalin, and DOMOM would be 94 times more potent. The 5‐HT 2A radioligand receptor binding studies showed that the affinities of DOMCl and DOMOM for the 5‐HT 2A receptor are less than expected but are nevertheless 1.6 and 8.7 times higher, respectively, than that of mescalin. Therefore, scheduling these substances as potential drugs of abuse might be considered.
Teilweise Sauerstoff-Wanderung in der photochemischen Wolff-Umlagerung – α-Oxocarben-Oxiren-Isomerisierung oder intermolekularer Mechanismus?
2003-06-01

Crossover experiments between isotopomeric species of 2-diazo-1-oxo-1-phenylethane ( 18 O, 13 C, D) establish beyond doubt that the oxygen migration accompanying the photochemical Wolff rearrangement is not the result of intermolecular processes. This is in agreement with a carbenecarbene rearrangement via an intermediate oxirene in competition to the rearrangement into a ketene, as reason for the partial oxygen migration in the Wolff rearrangement products.
Analyzing Sequential Data in Computer-Supported Collaborative Learning
2003-06-01

Representations and changes between them play a major role in education (e.g., Hewson, Beeth, &amp; Thorley, 1998), problem solving (e.g., Bauer &amp; Reiser, 1990), cognitive development (e.g., Vosniadou &amp; Brewer, 1992), and the history of science (e.g., Kuhn, 1970). By definition, change of representations is also indispensable for collaborative work since a common understanding or shared knowledge can only be achieved by a partial convergence of the knowledge structures of the collaborating subjects. This articles presents and discusses knowledge tracking (KT), viz., an approach to analyze cognition on the basis of symbolic sequential data. We describe the methodological aspects of KT and delineate the Web-based computer program (knowledge tracking engine, KTE) set up to run KT-analyses ( http://www.knowledge-tracking.com/ ). An empirical study in collaborative learning is taken to exemplify the usage of KT in analysis of computer supported collaboration.
η nucleus optical potential in a chiral unitary approach
2003-06-01

The self-energy of an η in a nuclear medium is calculated in a chiral unitary model, and applied to η states in nuclei. Our calculation predicts an attractive η nucleus optical potential which can accommodate many η bound states in different nuclei. 1.
Virtual Bronchoscopy: Comparison of Different Surface Rendering Models
2003-06-01

The aim of this study was to compare different representation models of surface-rendered virtual bronchoscopy. 10 consecutive patients with inoperable primary lung tumors underwent thin-section spiral computed tomography. The structures of interest, the tracheobronchial system and anatomical and pathological thoracic structures were segmented using an interactive threshold interval volume-growing segmentation algorithm and visualized with the aid of a color-coded surface rendering method. For virtual bronchoscopy, the tracheobronchial system was visualized using a triangle-surface rendering model, a shaded-surface rendering model and a transparent shaded-surface rendering model. The triangle-surface rendering model allowed optimum detailed spatial representation of the dimensions of extraluminal anatomical and pathological mediastinal structures. As the lumen of the tracheobronchial system was less well defined, the rendering model was of limited use for depiction of the airway surface. The shaded-surface rendering model facilitated an optimum assessment of the airway surface, but the mediastinal structures could not be depicted. The transparent shaded-surface rendering model provides simultaneous adequate to optimum visualization and assessment of the intraluminal airway surface and the extraluminal mediastinal structures as well as a quantitative assessment of the spatial relationship between these structures. Fast data acquisition with a multi-slice detector spiral computed tomography scanner and the use of virtual bronchoscopy with the transparent shaded-surface rendering model obviate the need for time consuming detailed analysis and presentation of axial source images by providing improved the diagnostic imaging of endotracheal and endobronchial diseases and offering a useful alternative to fiberoptic bronchoscopy.
LATTICE EFFECTIVE THEORY AND THE PHASE TRANSITION AT FINITE DENSITIES
2003-06-01

The transition from the hadronic phase to the phase of\\ncolor-superconductivity at large densities is addressed by an effective theory\\nwhich incorporates the Yang-Mills dynamics in addition to the di-quark degree\\nof freedom. A toy version of this theory is studied by lattice simulations. A\\nfirst order phase transition separates the regime of broken color-electric flux\\ntubes from the color superconducting phase. My findings suggest that the quark\\nand gluon liberation occurs at the same critical chemical potential.\\n
Nucleon-Nucleon High-Energy Scattering
2003-06-01

The high energy pn charge exchange and pp elastic scattering reactions are studied in an effective hadron model for the energy range of s ~ 50 to 400 GeV 2 . The main features of the observed differential cross section of the pn charge exchange reaction, the forward peak and the scaling behavior over the large energy range, are well reproduced by a combination of π-, ρ-exchange and a 4-Nucleon contact term. The latter acts as a background field which turns out to be naturally suppressed in elastic N N scattering but contributes significantly to the charge-exchange reaction.
A new allelic variation within the 5′‐flanking region of the interleukin‐10 gene
2003-06-01

Summary At −2471 bp from the transcriptional start site of the interleukin‐10 (IL‐10) gene, the inverted repeat TG/CA was previously identified and designated IL‐10.IR. In an analysis of samples from 200 Germans (Caucasian) and 286 Gabonese (Central African), three different alleles, IL‐10.IR6, IL‐10.IR7 and IL‐10.IR8, were identified. In the Caucasians, IL‐10.IR6 and IL‐10.IR8 were found only once, in each case with IL‐10.IR7 as the corresponding second allele.
Strong Optical Limiting of Soluble Axially Substituted Gallium and Indium Phthalocyanines
2003-06-02

Optical limiting in In‐ and Ga‐phthalocyanines exhibits a range of saturation densities and absorption cross‐section ratios. Substitution of the p ‐trifluoromethylphenyl group at the central metal in t Bu 4 PcGaCl and t Bu 4 PcInCl reduces the saturation energy density by a factor of &gt;3. Tailorable optical limiting properties are shown in the Figure, which plots the nonlinear absorption coefficient as a function of intensity for the five compounds studied.
Exclusion of BRAFV599E as a melanoma susceptibility mutation
2003-06-02

Abstract Very recently, BRAF mutations were found in about 2/3 of malignant melanomas and at lower frequencies in other human cancers. The BRAF gene codes for a protein in the mitogen‐activated protein kinase (MAPK) pathway. All mutations identified to date are within the kinase domain, with a single missense mutation (V599E) accounting for 80%. We investigated the hypothesis that this common somatic BRAF mutation (V599E) would contribute to melanoma predisposition in familial and polygenic malignant melanoma if occuring as a germ‐line mutation. We performed comprehensive mutational screening of exon 15 of BRAF using DHPLC (denaturing high‐performance liquid chromatography) and DNA sequencing techniques. No V599E mutation could be detected in 172 melanoma patients comprising 46 familial cases, 21 multiple melanoma patients and 106 cases with at least one first‐degree relative suffering from other cancers. We therefore conclude that the common somatic BRAF mutation V599E does not contribute to polygenic and familial melanoma predisposition. © 2003 Wiley‐Liss, Inc.
Ultimatum Games and Wages: Evidence of an 'Implicit Bargain'?
2003-06-02

In this paper, I argue that both ultimatum game outcomes and wages may be in¬fluenced by what the result of a bargain would have been: The players in the ultimatum game, just as the parties to the labor contract, seem to engage in what may be called an “implicit” or, in Selten' s words, an “imaginary” bargain. In determining ultimatum game outcomes, assuming an implicit bargain can account for the experimental evidence on the role of responder bargaining power. Moreover, the implications of the implicit bar¬gain for the wage setting process are compatible with the stylized facts of wage determination.