4,652 research outputs found
The Unity of the Human Person: A Central Concept in the Interface Between Medicine and Theology
Does the Prisoner's Dilemma Refute the Coase Theorem?
Two of the most important ideas in the philosophy of law are the “Coase Theorem” and the “Prisoner’s Dilemma.” In this paper, the authors explore the relation between these two influential models through a creative thought-experiment. Specifically, the paper presents a pure Coasean version of the Prisoner’s Dilemma, one in which property rights are well-defined and transactions costs are zero (i.e. the prisoners are allowed to openly communicate and bargain with each other), in order to test the truth value of the Coase Theorem. In addition, the paper explores what effect (a) uncertainty, (b) exponential discounting, (c) and elasticity have on the behavior of the prisoners in the Coasean version of the dilemma. Lastly, the paper considers the role of the prosecutor (and third-parties generally) in the Prisoner’s Dilemma and closes with some parting thoughts about the complexity of the dilemma. The authors then conclude by identifying the conditions under which the Prisoner’s Dilemma refutes the Coase Theorem
Characterization of Soil Nematode Community as Influenced by Weedy Plants and Edaphic Properties
Nematodes are one of the most critical species globally as they are part of most nutrient recycling. While nematodes play a vital role in nutrient cycling, little is known about them from an ecological standpoint. The majority of current research has focused on a singular component of the community, being those of herbivore/plant-parasitic nematodes. In this study, the community shifts of the nematode trophic groups were analyzed as influenced by native and invasive grasses species in the Lower Rio Grande Valley (LRGV) with the addition of edaphic soil properties.
In our study, the results indicate changes in the composition of the nematode community amongst native and invasive grass species in the LRGV. These shifts in composition were observed as individual nematode species such as Helicotylenchus spp and Pratylenchus spp were significantly different amongst the native and invasive plant species. Soil edaphic properties also had significant correlations with diversity and trophic nematode groups, particularly moisture
Prediction of non-genotoxic carcinogenicity based on genetic profiles of short term exposure assays
Non-genotoxic carcinogens are substances that induce tumorigenesis by non-mutagenic mechanisms and long term rodent bioassays are required to identify them. Recent studies have shown that transcription profiling can be applied to develop early identifiers for long term phenotypes. In this study, we used rat liver expression profiles from the NTP (National Toxicology Program, Research Triangle Park, USA) DrugMatrix Database to construct a gene classifier that can distinguish between non-genotoxic carcinogens and other chemicals. The model was based on short term exposure assays (3 days) and the training was limited to oxidative stressors, peroxisome proliferators and hormone modulators. Validation of the predictor was performed on independent toxicogenomic data (TG-GATEs, Toxicogenomics Project-Genomics Assisted Toxicity Evaluation System, Osaka, Japan). To build our model we performed Random Forests together with a recursive elimination algorithm (VarSelRF). Gene set enrichment analysis was employed for functional interpretation. A total of 770 microarrays comprising 96 different compounds were analyzed and a predictor of 54 genes was built. Prediction accuracy was 0.85 in the training set, 0.87 in the test set and increased with increasing concentration in the validation set: 0.6 at low dose, 0.7 at medium doses and 0.81 at high doses. Pathway analysis revealed gene prominence of cellular respiration, energy production and lipoprotein metabolism. The biggest target of toxicogenomics is accurately predict the toxicity of unknown drugs. In this analysis, we presented a classifier that can predict non-genotoxic carcinogenicity by using short term exposure assays. In this approach, dose level is critical when evaluating chemicals at early time points.Fil: Perez, Luis Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: González José, Rolando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; ArgentinaFil: Peral Garcia, Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico CONICET- La Plata. Instituto de Genética Veterinaria ; Argentin
Generalized Solutions of a Nonlinear Parabolic Equation with Generalized Functions as Initial Data
In \cite{bf} Br\'ezis and Friedman prove that certain nonlinear parabolic
equations, with the -measure as initial data, have no solution. However
in \cite{cl} Colombeau and Langlais prove that these equations have a unique
solution even if the -measure is substituted by any Colombeau
generalized function of compact support. Here we generalize Colombeau and
Langlais their result proving that we may take any generalized function as the
initial data. Our approach relies on resent algebraic and topological
developments of the theory of Colombeau generalized functions and results from
\cite{A}
Localization of ribosomal genes in three Pimelodus species (Siluriformes, Pimelodidae) of the São Francisco River: 5S genes as species markers and conservation of the 18S rDNA sites
Pimelodidae is one of the most representative of Neotropical catfish families. However, these fish are still poorly studied in terms of cytogenetics, especially regarding the application of more accurate techniques such as the chromosomal localization of ribosomal genes. In the present work, fluorescent in situ hybridization with 5S and 18S rDNA probes was employed for rDNA site mapping in Pimelodus sp., P. fur and P. maculatus from the São Francisco River in the Três Marias municipality - MG. The results from the application of the 18S probe confirmed the previous data obtained by silver nitrate staining, identifying a simple nucleolar organizing region system for these species. However, the labeling results from the 5S rDNA probe demonstrated a difference in the number and localization of these sites between the analyzed species. The obtained data allowed inferences on the possible processes involved in the karyotypic evolution of this genus.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
The flaring and quiescent components of the solar corona
The solar corona is a template to understand stellar activity. The Sun is a
moderately active star, and its corona differs from active stars: active
stellar coronae have a double-peaked EM(T) with the hot peak at 8-20 MK, while
the non flaring solar corona has one peak at 1-2 MK. We study the average
contribution of flares to the solar EM(T) to investigate indirectly the
hypothesis that the hot peak of the EM(T) of active stellar coronae is due to a
large number of unresolved solar-like flares, and to infer properties on the
flare distribution from nano- to macro-flares. We measure the disk-integrated
time-averaged emission measure, EM_F(T), of an unbiased sample of solar flares
analyzing uninterrupted GOES/XRS light curves over time intervals of one month.
We obtain the EM_Q(T) of quiescent corona for the same time intervals from the
Yohkoh/SXT data. To investigate how EM_F(T) and EM_Q(T) vary with the solar
cycle, we evaluate them at different phases of the cycle (from Dec. 1991 to
Apr. 1998). Irrespective of the solar cycle phase, EM_F(T) appears like a peak
of the distribution significantly larger than the values of EM_Q(T) for T~5-10
MK. As a result the time-averaged EM(T) of the whole solar corona is
double-peaked, with the hot peak, due to time-averaged flares, located at
temperature similar of that of active stars, but less enhanced. The EM_F(T)
shape supports the hypothesis that the hot EM(T) peak of active coronae is due
to unresolved solar-like flares. If this is the case, quiescent and flare
components should follow different scaling laws for increasing stellar
activity. In the assumption that the heating of the corona is entirely due to
flares, from nano- to macro-flares, then either the flare distribution or the
confined plasma response to flares, or both, are bimodal.Comment: 8 pages, 7 postscript figures, accepted for publication in Astronomy
and Astrophysic
Notas sobre propiedades espectrales de un operador, su heredabilidad y aplicaciones
In this paper we describe the behavior of Weyl type theorems or Weyl type properties, for an operator on a proper closed and -invariant subspace such that , for some , where and is an infinite-dimensional complex Banach space. Our main purpose is to show that for these subspaces (which generalize the case closed, for some ) a large number of Weyl type theorems are transmitted from to its restriction on and vice-versa. As application of our results, we obtain conditions for which Weyl type theorems are equivalent for two given operators. Also, we give conditions under which an operator acting on a subspace can be extended on the entire space preserving the Weyl type properties.Este art\'{\i}culo versa sobre el comportamiento de los Teoremas, o propiedades, de tipo Weyl para un operador sobre un subespacio propio cerrado y -invariante tal que , para alg\'{u}n , donde y es un espacio de Banach complejo e infinito dimensional. Nuestro principal prop\'{o}sito es exhibir que para tales subespacios (los cuales generalizan el caso cerrado, para alg\'{u}n ), una gran cantidad de Teoremas tipo Weyl se transmiten de a su restricci\'{o}n sobre y viceversa. Como aplicaci\'{o}n de nuestros resultados, obtenemos condiciones para que los Teoremas de tipo Weyl sean equivalentes para dos operadores dados. As\'{\i} como tambi\'{e}n, condiciones bajo las cuales un operador que act\'{u}a sobre un subespacio de un espacio dado, pueda extenderse a todo el espacio preserv\'{a}ndose las propiedades tipo Weyl
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