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101.
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We analyze the classical asset pricing model assuming non fully rationalagents.Agents forecast future prices cum dividend through an adaptive learning rule.This assumption provides an explanation of some anomalies encounteredin the empirical analysis of asset prices under full rationality:returns are serially correlated(positively over a short horizon and negatively over a longer horizon)and the dividend yield predicts future returns (positive correlation).Considering the continuous time limit process,the same regularities are established analytically for price increments. 相似文献
103.
J Seoane PI Varela-Centelles N González-Reforma A Aguado G Esparza 《Canadian Metallurgical Quarterly》1997,1(4):172-175
The role of dentists in both primary (promoting a healthier lifestyle) and secondary (early diagnosis) prevention of oral cancer is undeniable, and becomes particularly important as oral cancer is thought to be preceded by premalignant lesions or conditions in about one half of the cases. In these situations, there is the possibility for an early diagnosis which will definitively influence the survival rate. Thus, it is an undergraduate educational objective related to secondary prevention of oral cancer to increase the efficacy of screening of precancerous lesions/conditions. A questionnaire with 38 clinical cases including 16 benign lesions, 9 malignant lesions and 13 precancerous lesions or conditions was applied voluntarily to 3rd, 4th and 5th year University of Santiago de Compostela dental students on April 1996. The participation rate was 90% of the 3rd-year students, 60% in 4th-year class, and 50% of the 5th-year group. The agreement in the diagnosis with a panel of experts reached 81.45% for 5th-year students. Students of 3rd- and 4th-year scored lower percentages, probably due to the rarity of some of the conditions in our area. 5th-year students scored significantly higher values than 3rd- and 4th-year students. 相似文献
104.
Alan M. Allgeier Denise Andersen Michael D. Bartberger Emilio E. Bunel Robert D. Larsen Pingli Liu Thomas Storz Jason S. Tedrow 《Topics in Catalysis》2014,57(17-20):1335-1341
To overcome stability issues associated with the use of an aldehyde in a catalytic reductive amination reaction, a cyclic ketolactol (ω-hydroxylactone) was employed as an aldehyde surrogate to form a γ-aminoacid. The reaction proceeded most favorably over a Pt/C catalyst. The thermodynamics of each step were evaluated using density functional theory calculations, which correctly predicted the dominance of the ring-closed lactol reactant, yet suggested a preference for a ring-opened iminium intermediate upon the initial, slightly endoergic addition of amine substrate. Exoergic hydrogenation of this intermediate provided the thermodynamic driving force for the overall transformation. During development, the reaction was observed to depend significantly on the volumetric gas to liquid mass transfer coefficient (kLa) and this parameter was optimized to ensure successful scale up in a 400 L stirred tank reactor. 相似文献
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Marengo E Manfredi M Zerbinati O Robotti E Mazzucco E Gosetti F Bearman G France F Shor P 《Analytical chemistry》2011,83(17):6609-6618
The aim of this project is the development of a noninvasive technique based on LED multispectral imaging (MSI) for monitoring the conservation state of the Dead Sea Scrolls (DSS) collection. It is well-known that changes in the parchment reflectance drive the transition of the scrolls from legible to illegible. Capitalizing on this fact, we will use spectral imaging to detect changes in the reflectance before they become visible to the human eye. The technique uses multivariate analysis and statistical process control theory. The present study was carried out on a "sample" parchment of calfskin. The monitoring of the surface of a commercial modern parchment aged consecutively for 2 h and 6 h at 80 °C and 50% relative humidity (ASTM) was performed at the Imaging Lab of the Library of Congress (Washington, DC, U.S.A.). MSI is here carried out in the vis-NIR range limited to 1 μm, with a number of bands of 13 and bandwidths that range from about 10 nm in UV to 40 nm in IR. Results showed that we could detect and locate changing pixels, on the basis of reflectance changes, after only a few "hours" of aging. 相似文献
109.
Riccioli C Pérez-Marín D Guerrero-Ginel JE Saeys W Garrido-Varo A 《Applied spectroscopy》2011,65(7):771-781
This paper proposes a method based on near-infrared hyperspectral imaging for discriminating between terrestrial and fish species in animal protein by-products used in livestock feed. Four algorithms (Mahalanobis distance, Kennard-Stone, spatial interpolation, and binning) were compared in order to select an appropriate subset of pixels for further partial least squares discriminant analysis (PLS-DA). The method was applied to a set of 50 terrestrial and 40 fish meals analyzed in the 1000-1700 nm range. Models were then tested using an external validation set comprising 45 samples (25 fish and 20 terrestrial). The PLS-DA models obtained using the four subset-selection algorithms yielded a classification accuracy of 99.80%, 99.79%, 99.85%, and 99.61%, respectively. The results represent a first step for the analysis of mixtures of species and suggest that NIR-CI, providing valuable information on the origin of animal components in processed animal proteins, is a promising method that could be used as part of the EU feed control program aimed at eradicating and preventing bovine spongiform encephalopathy (BSE) and related diseases. 相似文献
110.
Chi Lu Ulrich P. Froriep Ryan A. Koppes Andres Canales Vittorio Caggiano Jennifer Selvidge Emilio Bizzi Polina Anikeeva 《Advanced functional materials》2014,24(42):6594-6600
Restoration of motor and sensory functions in paralyzed patients requires the development of tools for simultaneous recording and stimulation of neural activity in the spinal cord. In addition to its complex neurophysiology, the spinal cord presents technical challenges stemming from its flexible fibrous structure and repeated elastic deformation during normal motion. To address these engineering constraints, we developed highly flexible fiber probes, consisting entirely of polymers, for combined optical stimulation and recording of neural activity. The fabricated fiber probes exhibit low‐loss light transmission even under repeated extreme bending deformations. Using our fiber probes, we demonstrate simultaneous recording and optogenetic stimulation of neural activity in the spinal cord of transgenic mice expressing the light sensitive protein channelrhodopsin 2 (ChR2). Furthermore, optical stimulation of the spinal cord with the polymer fiber probes induces on‐demand limb movements that correlate with electromyographical (EMG) activity. 相似文献