julilili42/papers huggingface dataset:
Efficient Compression of 3D Dynamic Mesh Sequences
2007-01-01

Sample frames of the animations used for the analysis. From left to right: dance with 14, dolphin with 9, chicken with 10 and cow with 6 clusters. Each cluster is colored differently and encoded separately. This paper presents a new compression algorithm for 3D dynamic mesh sequences based on the local principal component analysis (LPCA). The algorithm clusters the vertices into a number of clusters using the local similarity between the trajectories in a coordinate system that is defined in each cluster, and thus transforms the original vertex coordinates into the local coordinate frame of their cluster. This operation leads to a strong clustering behavior of vertices and makes each region invariant to any deformation over time. Then, each cluster is efficiently encoded with the principal component analysis. The appropriate numbers of basis vectors to approximate the clusters are optimally chosen using the bit allocation process. For further compression, quantization and entropy encoding are used. According to the experimental results, the proposed coding scheme provides a significantly improvement in compression ratio over existing coders.
Alterations of acetylcholinesterase activity after traumatic brain injury in rats
2007-01-01

Objective: The cholinergic system is highly vulnerable to traumatic brain injury (TBI). However, limited information is available to what extent the degrading enzyme acetylcholinesterase (AChE) is involved. The present study addresses this question.Method: Thirty-six anaesthetized Sprague-Dawley rats were subjected to sham operation or to TBI using controlled cortical impact (CCI). The AChE activity was histochemically determined in frozen brain slices at 2, 24 and 72 hours after TBI.Results: High enzyme activity was observed in regions rich in cholinergic innervation such as the olfactory tubercle, basal forebrain, putamen and superior colliculi. Low activity was found in the cortex, cerebellum and particularly in the white matter. A decrease of AchE activity (20–35%) was found in the hippocampus and hypothalamus already at 2 hours after TBI. An increase of ∼30% was found in the basal forebrain at 2 and 24 hours. No changes occurred at 72 hours.Conclusion: The findings are consistent with impairment of the cholinergic neurotransmission after TBI and suggest the involvement of the AChE in short-term regulatory mechanisms.
Thyrotropin Serum Concentrations in Healthy Volunteers Are Associated with Depression-Related Personality Traits
2007-01-01

&lt;i&gt;Background:&lt;/i&gt; Alterations of the hypothalamic-pituitary-thyroid system at the hypophyseal level have been described in affective disorders. The NEO Five-Factor Inventory is a widely used instrument, which assesses neuroticism, a strong marker for vulnerability to depression. &lt;i&gt;Methods:&lt;/i&gt; Endogenous serum concentrations of thyroid-stimulating hormone (TSH), free T3 and free T4 were measured and the NEO Five-Factor Inventory was performed in 121 healthy unrelated volunteers (51 male, 70 female; median age: 23 years, range from 17 to 71). &lt;i&gt;Results:&lt;/i&gt; The TSH serum concentrations showed a median of 1.35 mU/l with a range from 0.1 to 4.0. The free T3 serum concentrations were 5.2 ± 0.7 pmol/l (mean ± SD), and the free T4 concentrations 16.5 ± 2.4 pmol/l (mean ± SD). The power of 0.4 of the TSH serum concentration and the logarithm of the depression-related factor neuroticism had a bivariate normal distribution and were negatively correlated (r = –0.337, p = 0.0002). &lt;i&gt;Conclusion:&lt;/i&gt; Low TSH levels in healthy humans might be linked to an increased risk to develop depression.
Market Responses to Buy Recommendations Issued by Personal Finance Magazines: Effects of Information, Price-Pressure, and Company Characteristics
2007-01-01

Abstract This paper analyzes explicit buy recommendations for stocks published by German Personal Finance Magazines from 1995 to 2003. These recommendations earn significant abnormal returns of 2.58% within the five days around the publication day. Both the price-pressure hypothesis and the information hypothesis can be confirmed by our data. The price-pressure effect is most evident for small stocks and glamour stocks. However, whereas the initial price reaction to small stocks is additionally driven by permanent information value, this does not hold true for glamour stocks. In contrast, value stocks are associated with high cumulative abnormal returns that are solely driven by information value.
Molecular recognition in molecular tweezers systems: quantum-chemical calculation of NMR chemical shifts
2007-01-01

Quantum-chemical calculations for molecular tweezers systems are presented, where the focus is not only on the recognition process in the host-guest systems, but on the self aggregation of the tweezers host as well. Such intermolecular interactions influence the corresponding NMR spectra strongly by up to 6 ppm for proton chemical shifts, since ring-current effects are particularly important. The quantum-chemical results allow one to reliably assign the spectra and to gain information both on the structure and on the importance of intra- and intermolecular interactions. In addition, we study the accuracy of a variety of density functionals for describing the present host-guest systems, where we observe a considerable underestimation of ring-current effects on (1)H NMR chemical shifts at the density functional theory (DFT) level using smaller basis sets such as 6-31G**, so that larger bases like TZP are required. This stands in contrast to the behavior of the Hartree-Fock scheme, where small basis sets, such as 6-31G**, provide reliable (1)H NMR shieldings for molecular tweezers systems.
BACE1 and Mutated Presenilin-1 Differently Modulate Aβ40 and Aβ42 Levels and Cerebral Amyloidosis in APPDutch Transgenic Mice
2007-01-01

APPDutch transgenic (tg) mice develop cerebral amyloid angiopathy (CAA) that consists mainly of AβDutch40, with virtually no parenchymal amyloid plaques. To modulate cerebral amyloidosis, we crossbred APPDutch mice with either BACE1 tg mice to increase total AβDutch, or with G384A-mutated PS1 tg mice to elevate the ratio of AβDutch42 to AβDutch40. We analyzed all mice at 22 months of age. Compared to APPDutch mice, double-tg APPDutch/BACE1 mice revealed increased CAA mainly due to extensive vascular amyloid accumulation in the thalamus. In addition, they developed parenchymal amyloid in cortex and subiculum. In contrast, APPDutch/G384A-PS1 mice showed extensive, predominantly parenchymal amyloid throughout the entire brain, interestingly, even in the thalamus. The amyloid, composed largely of AβDutch42, was different compared to that in APPDutch/BACE1 mice which was composed mainly of AβDutch40. In summary, these mouse models reveal a broad variety and region-specificity of parenchymal versus vascular cerebral amyloid. This is partially explained by the absolute amount of neuronally produced AβDutch42 and AβDutch40 and ratio between the two. We conclude that the absolute levels of Aβ in combination with the ratio of Aβ42 to Aβ40 play a key role in determining the cerebral compartment and brain region in which Aβ is deposited.
Sitagliptin with metformin: Profile of a combination for thetreatment of type 2 diabetes
2007-01-01

Sitagliptin, a novel orally-active dipeptidyl-peptidase (DPP-4) inhibitor has been introduced into type 2 diabetes therapy. Sitagliptin inhibits the degradation of glucagon-like peptide-1 (GLP-1) and gastric inhibitory polypeptide (GIP), as well as that of other regulatory peptides important for glucose homeostasis. It reduces haemoglobin A1c (HbA1c), fasting and postprandial glucose by glucose- dependent stimulation of insulin secretion and inhibition of glucagon secretion. Sitagliptin is weight neutral. Indirect measures show a possible improvement of beta-cell function. Sitagliptin does not cause hypoglycemia when compared to metformin or placebo. Metformin, which has a different unique mechanism, has been used in type 2 diabetes for approximately 50 years. Metformin improves insulin resistance and is the first-line antidiabetic drug in use today. The combination of a DPP-4 inhibitor with metformin allows a broad and complementary spectrum of antidiabetic actions. This combination does not increase the risk of hypoglycaemia nor does it promote weight gain, an adverse effect of various other oral antidiabetic combinations. This article gives an overview of the data available on the combined antidiabetic effects of metformin and sitagliptin.
Integrated Temperature, Humidity and Gas Sensors on Flexible Substrates for Low-Power Applications
2007-01-01

Temperature, gas and humidity resistive/ capacitive sensors on flexible substrates from organic materials, suitable for RFID mobile applications, have been produced and investigated. The sensor implementation solutions are providing simple, versatile and low power temperature and gas detection. The device structure was developed together with the data evaluation strategies based on last generation SigmaDelta analog (resistance and capacitance) to digital converters. We demonstrate the possibility of developing gas sensors on humidity sensitive substrates, having temperature corrected responses. The proposed device concept is aimed to evolve towards "flexible & full plastic" implementations.
Expanding the enantioselectivity of the gas‐chromatographic chiral stationary phase Chirasil‐Val‐C11 by doping it with octakis(3‐O‐butanoyl‐2,6‐di‐O‐n‐pentyl)‐γ‐cyclodextrin
2007-01-01

Abstract Combination of the enantioselective properties of the two versatile gas‐chromatographic chiral stationary phases (CSPs) octakis(3‐ O ‐butanoyl‐2,6‐di‐ O ‐ n ‐pentyl)‐γ‐CD (Lipodex E) 1 and L ‐valine‐diamide‐based CSP Chirasil‐Val‐C 11 2 has been realized by doping the chiral polymer 2 with the nonpolymeric selector 1 . The resulting mixed‐mode CSP Chirasil‐Val(γ‐Dex) 3 was found to have a greatly improved enantioselectivity toward proline and aspartic acid (as N ‐trifluoroacetyl ethyl or methyl esters) in comparison to the single‐mode CSP 2 . The presence of the CD selector in 3 extended the scope of gas‐chromatographic enantioseparations achievable on 2 to underivatized alcohols, terpenes, and other chiral compounds that are exclusively enantioseparated on 1 .
Designing and exploiting small multimedia corpora for autonomous learning and teaching
2007-01-01

The use of corpora in the second-language learning context requires the availability of corpora which are pedagogically relevant with regard to choice of discourse, choice of media, annotation and size. Here I describe a pedagogically motivated corpus design which supports a direct and efficient exploitation of the corpus by learners and teachers. One of the major guidelines is Widdowson's (2003) claim that the successful use of corpora requires a learner's (and teacher's) ability to 'authenticate' the corpus materials. In line with this, I argue for the development of small and pedagogically annotated corpora which enable us to combine two methods of analysis and exploitation to mutual benefit: (1) a corpus-based approach (i.e. 'vertical reading' of e.g. concordances), which provides patterns of language use; and (2) a discourse-based approach, which focuses on the analysis of the individual texts in the corpus, and of linguistic means of expression in relation to their communicative (situational) and cultural embedding. To illustrate my points, I use a small multimedia corpus of spoken English which is currently being developed as a model corpus with pedagogical goals in mind.
Development of reverse phase protein microarrays for clinical applications and patient-tailored therapy
2007-01-01

While genomics provide important information about the somatic genetic changes, and RNA transcript profiling can reveal important expression changes that correlate with outcome and response to therapy, it is the proteins that do the work in the cell. At a functional level, derangements within the proteome, driven by post-translational and epigenetic modifications, such as phosphorylation, is the cause of a vast majority of human diseases. Cancer, for instance, is a manifestation of deranged cellular protein molecular networks and cell signaling pathways that are based on genetic changes at the DNA level. Importantly, the protein pathways contain the drug targets in signaling networks that govern overall cellular survival, proliferation, invasion and cell death. Consequently, the promise of proteomics resides in the ability to extend analysis beyond correlation to causality. A critical gap in the information knowledge base of molecular profiling is an understanding of the ongoing activity of protein signaling in human tissue: what is activated and “in use” within the human body at any given point in time. To address this gap, we have invented a new technology, called reverse phase protein microarrays, that can generate a functional read-out of cell signaling networks or pathways for an individual patient obtained directly from a biopsy specimen. This “wiring diagram” can serve as the basis for both, selection of a therapy and patient stratification.
Treatment of Dementia in Parkinsonian Syndromes with Cholinesterase Inhibitors
2007-01-01

In Parkinsonian syndromes behavioural symptoms and dementia can be even more debilitating than motor symptoms and are an important predictor for nursing home placement and mortality. Neuropathologically, dementia seems to be primarily related to cortical changes rather than to subcortical alterations. Concerning neurotransmitter systems, the cholinergic system has been proposed to play a key role in cognitive disturbances. Based on studies with patients with Alzheimer disease, the application of cholinesterase inhibitors is vividly discussed also for dementia associated with parkinsonian syndromes. This review focuses on the specific symptoms of dementia in different parkinsonian syndromes and critically questions the effect of cholinergic treatment on cognitive functions in patients with extrapyramidal syndromes and dementia. There is evidence that medication with some cholinesterase inhibitors can enhance cognition as well as activities of daily living in dementia with Parkinson’s disease and seems to reduce behavioural disturbances in both dementia with Parkinson’s disease and dementia with Lewy bodies. The effect of treatment with cholinesterase inhibitors in progressive supranuclear palsy and corticobasal degeneration warrants carefully designed studies including a sufficient number of patients and symptom-adopted dementia scales.
Alterations in the Cytoplasmic Domain of CLCN2 Result in Altered Gating Kinetics
2007-01-01

Mutations in the human ClC-2 Cl(-) channel have been described to influence its function dramatically. To test for naturally occurring gene variants in a human population and their functionality, all 24 CLCN2 exons from a Central African population were sequenced. Six single amino acid exchanges in the intracellular N-terminus (P48R, R68H), in the pore domain (G199A), or in the intracellular C-terminus (R646Q, R725W, R747H) were identified at low frequency. Heterologous expression of these polymorphisms in Xenopus laevis oocytes demonstrated their functional significance as determined by two-electrode voltage-clamp. The polymorphisms R68H, R725W, and R747H exhibited faster voltage-stimulated gating as compared to the wild type channel, resulting in higher steady state currents of R725W. Probably due to decreased surface expression P48R, R68H, and R646Q mutants generated lower currents than the wild type channels. The inward currents of the mutated channels R725W, R747H, and G199A failed to increase during hypotonic swelling, a defect paralleled by impaired swelling-accelerated voltage-gating in one mutant (G199A). In conclusion, the Africans' gene pool comprises CLCN2 gene variants in the N-terminus, the C-terminus or the pore domain that affect surface expression and voltage- or cell-swelling-stimulated channel gating.
Evidence of homing following translocation of long‐tailed bats (Chalinolobus tuberculatus) at Grand Canyon Cave, New Zealand
2007-01-01

Abstract Homing behaviour in the New Zealand long‐tailed bat (Chalinolobus tuberculatus), a temperate insectivorous species, was investigated at Grand Canyon Cave, central North Island. A pilot study of nine adult male bats was conducted to determine whether use of the cave was regular enough for a homing study. Eight bats returned to the cave over the 3‐week monitoring period, six on the night following release. Nine additional bats carrying radio transmitters were then released at three sites (three at each site) c. 5, 10 and 20 km due east of the cave; sites estimated to be located within, on the border of, and outside the population's known familiar area respectively. All but one of these nine bats were subsequently detected at the cave. Results suggest that adult long‐tailed bats are able to return home following displacement both inside and outside their familiar area. Implications of these findings for translocations of bats and the possession of a potential long‐distance navigation system by this species are discussed.
Magnetic Field Distribution and Signal Decay in Functional MRI in Very High Fields (up to 9.4 T) Using Monte Carlo Diffusion Modeling
2007-01-01

Extravascular signal decay rate R2 or R2 ∗ as a function of blood oxygenation, geometry, and field strength was calculated using a Monte Carlo (MC) algorithm for a wider parameter range than hitherto by others. The relaxation rates of gradient‐recalled‐echo (GRE) and Hahn‐spin‐echo (HSE) imaging in the presence of blood vessels (ranging from capillaries to veins) have been computed for a wide range of field strengths up to 9.4 T and 50% blood deoxygenation. The maximum HSE decay was found to be shifted to lower radii in higher compared to lower field strengths. For GRE, however, the relaxation rate was greatest for large vessels at any field strength. In addition, assessments of computational reliability have been carried out by investigating the influence of the time step, the Monte Carlo step procedure, boundary conditions, the number of angles between the vessel and the exterior field B 0 , the influence of neighboring vessels having the same orientation as the central vessel, and the number of proton spins. The results were compared with those obtained from a field distribution of the vessel computed by an analytic formula describing the field distribution of an ideal object (an infinitely long cylinder). It was found that the time step is not critical for values equal to or lower than 200 microseconds. The choice of the MC step procedure (three‐dimensional Gaussian diffusion, constant one‐ or three‐dimensional diffusion step) also failed to influence the results significantly; in contrast, the free boundary conditions, as well as taking too few angles into account, did introduce errors. Next neighbor vessels with the same orientation as the main vessel did not contribute significantly to signal decay. The total number of particles simulated was also found to play a minor role in computing R2/ R2 ∗ .
Supporting controversial CSCL discussions with augmented group awareness tools
2007-01-01

An experimental study investigated the influence of an augmented group awareness tool on controversial online discussions and decisions made by 4-person learner groups. The study employed an informed minority paradigm where one group member holds a correct viewpoint, but is faced with a 3-person majority holding an incorrect viewpoint. Within this paradigm, groups using an augmented group awareness tool based on learner ratings of agreement and novelty of contributions were compared to groups using a standard online discussion tool. It was shown that majority influence occurred in unsupported groups, whereas augmented group awareness tools strengthened minority influence, as indicated by group decisions and individual correctness of decisions.
Possibilities of dose reduction in lateral cephalometric radiographs and its effects on clinical diagnostics
2007-01-01

As there is only minimal dose reduction at increased tube potential settings, for a dose reduction, it seems to be more useful to use storage phosphor plates at unchanged tube potential and halved milliampere seconds settings compared with the film-screen combination.
Study of the 60Ni(n,2n)59Ni reaction from threshold to 20 MeV and the half-life of 59Ni
2007-01-01

The production of long-lived 59 Ni as activation product is of concern for a fusion environment.Its main production is the (n,2n) reaction of 14-MeV neutrons on stable 60 Ni with some additional contributions from neutron capture reactions on 58 Ni via lower energy neutrons.Information for the production of 59 Ni via the (n,2n) reaction is strongly discordant or completely missing.Ni metal samples were available to us which had previously been irradiated with neutrons at energies of 17 and 19 MeV.After the irradiation the amount of produced 59 Ni was measured via accelerator mass spectrometry utilizing the 14-MV tandem accelerator of Maier-Leibnitz Laboratory in Munich.A second important issue is the half-life of 59 Ni: The accepted value is t 1/2 = (76 ± 5) kyr which is substantially lower than the value of (108 ± 13) kyr which was obtained a few years later in an independent measurement.The later value is based on relative measurements using the thermal 54 Fe neutron capture cross section.A new measurement of this cross section is underway at the VERA laboratory in Vienna applying AMS for the quantification of 55 Fe.The new data will allow to generate a more precise value for the half-life of 59 Ni compared to the previous one.
Support Vector Machine-Based Prediction of MHC-Binding Peptides
2007-01-01

The use of major histocompatibility complex (MHC) class I binding peptides for immunotherapeutic purposes has shown promising results in recent years. The identification of such peptides mostly starts with predicting MHC-binding peptides, given a protein of interest. An accurate prediction method can reduce the number of peptides that needs to be tested experimentally. This protocol describes in this describes how support vector machines (SVMs) can be used for predicting MHC class I binding peptides. Focus is given on data representation, the concept of cross-validation, and how optimal SVM-specific parameters are obtained.
Blood Transfusion and Spread of Variant Creutzfeldt-Jakob Disease
2007-01-01

Variant Creutzfeldt-Jakob disease (vCJD) may be transmissible by blood. To prevent secondary transmission through blood components, several countries have started to exclude as donors persons who have received a blood transfusion. We investigated the effectiveness of this measure by using a dynamic age-structured model. It is the first such model based on epidemiologic data: 1) blood donor activities, 2) a case-control study on CJD, 3) age distribution of recipients, and 4) death of recipients of blood transfusions. The model predicts that an infection like vCJD, which has been introduced into the population by the alimentary route, could not become endemic by transfusion alone and that only <1% of cases would be avoided by excluding from blood donation those persons who have received a transfusion.