Sobre la compatibilidad entre realismo y relativismo conceptual : Un exámen de la tesis de Putnam, desde un punto de vista lógico

Las indagaciones en la pregunta por lo que hay permiten distinguir a grandes rasgos entre dos enfoques: uno, el de los pensadores que entendieron que el tema a investigar era la naturaleza y estructura del mundo, y otro, el de aquellos quienes, al sostener que describir el mundo no es simplemente copiarlo, atendieron a lo que se llamó esquema conceptual: esto es, al marco conceptual cuya forma toman las descripciones del mundo. La situación se puede plantear como un dilema, ninguno de cuyos cuernos permite alentar esperanzas de avances bien fundados. O bien se pretende describir el mundo, tal como es, sin contemplar el hecho de que esa descripción incluye elecciones conceptuales propias de un sujeto, o bien se centra la investigación en los rasgos de el/los esquema/s conceptual/es imprescindibles para construir una descripción del mundo, imposibilitando, con ello, el acceso a la realidad tal como ésta es. En el siglo XX se cuenta con recursos de sistemas de lógica considerablemente más desarrollados y abarcadores (en sus posibilidades de aplicación) que los anteriores. Tales recursos brindan nuevas posibilidades de abordaje de la pregunta por lo que hay, no sólo por los ámbitos que se clarifican mediante ellos, sino también por el sustento que ofrecen para la reflexión filosófica los resultados obtenidos. Los avances producidos en el ámbito de la lógica en algo más de un siglo tuvieron variadas repercusiones en el enfoque y el tratamiento de distintas cuestiones filosóficas. Así, se ha echado mano a conceptos y recursos de lógica al considerar preguntas acerca de la estructura del mundo. Para la determinación de los componentes de la realidad se ha recurrido a la lógica, desde diversas posiciones filosóficas. Por ejemplo, se ha entendido que la lógica subyacente a la teoría científica brinda en algún sentido elementos para determinar la ontología (o para descartar la posibilidad de hacerlo, o para establecer qué función cumple la noción de ontología en la teoría científica). También, desde una óptica más amplia, se ha intentado mostrar que el uso del lenguaje tiene consecuencias respecto de la ontología. Hilary Putnam ha sugerido la posibilidad de ser al mismo tiempo un realista y un relativista conceptual. Involucra consideraciones como las mencionadas, respecto de lógica y ontología. Su objetivo es el intento de hacer justicia a la realidad y al misterio de nuestro mundo de sentido común. Tomo esta tesis como una propuesta de trabajo. Me interesa pensar en cómo ofrecer algunos elementos de juicio para evaluar sus alcances. Para ello, examino la sugerencia de Putnam mediante un ejemplo construido con ese objetivo. Entiendo que se requerirán, al menos, dos esquemas conceptuales diferentes: al que surgiría de la lógica de orden 1, tal como la desarrolla Quine, y al que podría obtenerse a partir de la teoría de objetos no existentes de Castañeda. Se contará así con elementos de juicio más precisos que los habituales para evaluar las consecuencias que se seguirían para la ontología en caso de sostener ambos esquemas conceptuales, en consonancia con la propuesta de Putnam que se ha tomado como objetivo general del proyecto

Sobre la compatibilidad entre realismo y relativismo conceptual : Un exámen de la tesis de Putnam, desde un punto de vista lógico

Las indagaciones en la pregunta por lo que hay permiten distinguir a grandes rasgos entre dos enfoques: uno, el de los pensadores que entendieron que el tema a investigar era la naturaleza y estructura del mundo, y otro, el de aquellos quienes, al sostener que describir el mundo no es simplemente copiarlo, atendieron a lo que se llamó esquema conceptual: esto es, al marco conceptual cuya forma toman las descripciones del mundo. La situación se puede plantear como un dilema, ninguno de cuyos cuernos permite alentar esperanzas de avances bien fundados. O bien se pretende describir el mundo, tal como es, sin contemplar el hecho de que esa descripción incluye elecciones conceptuales propias de un sujeto, o bien se centra la investigación en los rasgos de el/los esquema/s conceptual/es imprescindibles para construir una descripción del mundo, imposibilitando, con ello, el acceso a la realidad tal como ésta es. En el siglo XX se cuenta con recursos de sistemas de lógica considerablemente más desarrollados y abarcadores (en sus posibilidades de aplicación) que los anteriores. Tales recursos brindan nuevas posibilidades de abordaje de la pregunta por lo que hay, no sólo por los ámbitos que se clarifican mediante ellos, sino también por el sustento que ofrecen para la reflexión filosófica los resultados obtenidos. Los avances producidos en el ámbito de la lógica en algo más de un siglo tuvieron variadas repercusiones en el enfoque y el tratamiento de distintas cuestiones filosóficas. Así, se ha echado mano a conceptos y recursos de lógica al considerar preguntas acerca de la estructura del mundo. Para la determinación de los componentes de la realidad se ha recurrido a la lógica, desde diversas posiciones filosóficas. Por ejemplo, se ha entendido que la lógica subyacente a la teoría científica brinda en algún sentido elementos para determinar la ontología (o para descartar la posibilidad de hacerlo, o para establecer qué función cumple la noción de ontología en la teoría científica). También, desde una óptica más amplia, se ha intentado mostrar que el uso del lenguaje tiene consecuencias respecto de la ontología. Hilary Putnam ha sugerido la posibilidad de ser al mismo tiempo un realista y un relativista conceptual. Involucra consideraciones como las mencionadas, respecto de lógica y ontología. Su objetivo es el intento de hacer justicia a la realidad y al misterio de nuestro mundo de sentido común. Tomo esta tesis como una propuesta de trabajo. Me interesa pensar en cómo ofrecer algunos elementos de juicio para evaluar sus alcances. Para ello, examino la sugerencia de Putnam mediante un ejemplo construido con ese objetivo. Entiendo que se requerirán, al menos, dos esquemas conceptuales diferentes: al que surgiría de la lógica de orden 1, tal como la desarrolla Quine, y al que podría obtenerse a partir de la teoría de objetos no existentes de Castañeda. Se contará así con elementos de juicio más precisos que los habituales para evaluar las consecuencias que se seguirían para la ontología en caso de sostener ambos esquemas conceptuales, en consonancia con la propuesta de Putnam que se ha tomado como objetivo general del proyecto

Composition of fossil manganese nodules from Costa Rica

Horizons of several types of Upper Jurassic to Lower Cretaceous manganese nodules occur locally in sequences of radiolarian cherts within the Nicoya Ophiolite Complex (NW Costa Rica). Field studies, X-ray diffraction analysis, petrographic, chemical and experimental studies give evidence of a sedimentary, early diagenetic origin of the nodules, in contrast to earlier suggestions. Smooth, discoidal, compact and very dense nodules with diameters of some mm to 9 cm dominate. They are characterized by braunite, hollandite, pyrolusite and quartz as well as 39-61% Mn, 0.9-1.6% Fe, 5-26% SiO2, 1.3-1.9% Al2O3, 1.5-3.0% Ba, 460-5400 ppm Cu, 85-340 ppm Ni and 40-130 ppm Co, among others. It is suggested that the original mineralogy (todorokite?) was altered during thermometamorphic (braunite) and hydrothermal (hollandite. pyrolusite) events. Petrographic similarities between the fossil nodules and modern deep-sea nodules are striking. Using standard hydrothermal techniques in an experimental study it is shown that under special conditions, braunite can be produced from modern nodule material.

Morphological descriptions from the recent bivalve of the genus Calyptogena (Vesicomyidae)

The genus Calyptogena (Bivalvia: Vesicomyidae) comprises highly specialized bivalves living in symbiosis with sulphur-oxidizing bacteria in reducing habitats. In this study, the genus is revised using shell and anatomical features. The work is based on type material, as well as on the extensive collection of vesicomyids obtained during twelve expeditions to the Pacific and Indian Oceans. Nine Recent species are ascribed to the genus Calyptogena, four of which are new: C. pacifica Dall, 1891, C. fausta Okutani, Fujikura & Hashimoto, 1993, C. rectimargo Scarlato, 1981, C. valdiviae (Thiele & Jaeckel, 1931), C. gallardoi Sellanes & Krylova, 2005, C. goffrediae n. sp., C. starobogatovi n. sp., C. makranensis n. sp. and C. costaricana n. sp. The characteristic features of Calyptogena are: shell up to 90 mm in length, elongate-elliptical or elongate; presence of escutcheon; presence of broad posterior ramus (3b) of right subumbonal cardinal tooth as well as right posterior nymphal ridge; absence of pallial sinus as a result of attachment of intersiphonal septal retractor immediately adjacent to ventral surface of posterior adductor; absence of processes on inner vulva of inhalant siphon; presence of inner demibranch only, with descending and ascending lamellae with interlamellar septa not divided into separate tubes. The most closely related taxa to Calyptogena are probably the genus Isorropodon Sturany, 1896, and the group of species represented by 'Calyptogena' phaseoliformis Métivier, Okutani & Ohta, 1986. These groups have several characters in common, namely absence of pallial sinus, presence of single inner pair of demibranchs and absence of processes on inner vulva of inhalant siphon. The worldwide distribution of the genus Calyptogena suggests that methane seeps at continental margins are the major dispersal routes and that speciation was promoted by geographical isolation. Recent species diversity and fossil records indicate that the genus originated in the Pacific Ocean. Sufficient data to discuss the distribution at species level exist only for C. pacifica, which has a remarkably narrow bathymetric range. Published studies on the physiology of C. pacifica suggest that adaptation to a specific geochemical environment has led to coexisting vesicomyid genera. The bacteria-containing gill of C. pacifica and other Calyptogena species is one of the most specialized in the family Vesicomyidae and may reflect these ecological adaptations.

Der kleine Partheigänger und Krieger vorzüglich für den jungen Scharfschützen ...

von W. v. Reiche, Lieutenant beim Königl. Preuß. Regiment

Ex situ sulphate reduction rates of sediment at the rim of a vesicomyd clam colony in the Japan Deep Sea Trench (dive 955)

Sediment samples were collected from the rim of a large vesicomyid clam colony in the Japan Deep Sea Trench. Immediately after sample recovery onboard, the sediment core was sub-sampled for ex situ rate measurements. Sulfate reduction were measured ex situ by the whole core injection method with three replicates. We incubated the samples at in situ temperature (1.5°C) for 48 hours with carrier-free 35SO4 (dissolved in water, 50 kBq). Sediment was fixed 20 ml ZnAc solution (20%, w/v) for AOM or SR. Turnover rates were measured as previously described (Kallmeyer et al., 2004).

Ex situ sulphate reduction rates of sediment at the rim of a vesicomyd clam colony in the Japan Deep Sea Trench (dive 957)

Sediment samples were collected from the rim of a large vesicomyid clam colony in the Japan Deep Sea Trench. Immediately after sample recovery onboard, the sediment core was sub-sampled for ex situ rate measurements. Sulfate reduction were measured ex situ by the whole core injection method with three replicates. We incubated the samples at in situ temperature (1.5°C) for 48 hours with carrier-free 35SO4 (dissolved in water, 50 kBq). Sediment was fixed 20 ml ZnAc solution (20%, w/v) for AOM or SR. Turnover rates were measured as previously described (Kallmeyer et al., 2004).

Proceedings of the Biological Society of Washington.

v. 5 (1888-1890)

UMA ANÁLISE DA RELAÇÃO ENTRE VARIÁVEIS MACROECONÔMICAS E O COMPORTAMENTO DAS AÇÕES DE MAIOR LIQUIDEZ DO ÍNDICE IBOVESPA

As ações de maior liquidez do índice IBOVESPA, refletem o comportamento das ações de um modo geral, bem como a relação das variáveis macroeconômicas em seu comportamento e estão entre as mais negociadas no mercado de capitais brasileiro. Desta forma, pode-se entender que há reflexos de fatores que impactam as empresas de maior liquidez que definem o comportamento das variáveis macroeconômicas e que o inverso também é uma verdade, oscilações nos fatores macroeconômicos também afetam as ações de maior liquidez, como IPCA, PIB, SELIC e Taxa de Câmbio. O estudo propõe uma análise da relação existente entre variáveis macroeconômicas e o comportamento das ações de maior liquidez do índice IBOVESPA, corroborando com estudos que buscam entender a influência de fatores macroeconômicos sobre o preço de ações e contribuindo empiricamente com a formação de portfólios de investimento. O trabalho abrangeu o período de 2008 a 2014. Os resultados concluíram que a formação de carteiras, visando a proteção do capital investido, deve conter ativos com correlação negativa em relação às variáveis estudadas, o que torna possível a composição de uma carteira com risco reduzido.

Respiratory microbiota resistance and resilience to pulmonary exacerbation and subsequent antimicrobial intervention

This study was supported by the UK Natural Environment Research Council (NE/H019456/1) to CJvdG, by the Wellcome Trust (WT 098051) to AWW and JP for sequencing costs, and by The Anna Trust (KB2008) to KDB. AWW and The Rowett Institute of Nutrition and Health, University of Aberdeen, receive core funding support from the Scottish Government Rural and Environmental Science and Analysis Service (RESAS). We thank Paul Scott, Richard Rance and the Wellcome Trust Sanger Institute’s sequencing team for generating 16S rRNA gene sequence data.

Two domains within σN (σ54) cooperate for DNA binding

The σ-N (σN) subunit of the bacterial RNA polymerase is a sequence specific DNA-binding protein. The RNA polymerase holoenzyme formed with σN binds to promoters in an inactive form and only initiates transcription when activated by enhancer-binding positive control proteins. We now provide evidence to show that the DNA-binding activity of σN involves two distinct domains: a C-terminal DNA-binding domain that directly contacts DNA and an adjacent domain that enhances DNA-binding activity. The sequences required for the enhancement of DNA binding can be separated from the sequences required for core RNA polymerase binding. These results provide strong evidence for communication between domains within a transcription factor, likely to be important for the function of σN in enhancer-dependent transcription.

BIND—The Biomolecular Interaction Network Database

The Biomolecular Interaction Network Database (BIND; http://binddb.org) is a database designed to store full descriptions of interactions, molecular complexes and pathways. Development of the BIND 2.0 data model has led to the incorporation of virtually all components of molecular mechanisms including interactions between any two molecules composed of proteins, nucleic acids and small molecules. Chemical reactions, photochemical activation and conformational changes can also be described. Everything from small molecule biochemistry to signal transduction is abstracted in such a way that graph theory methods may be applied for data mining. The database can be used to study networks of interactions, to map pathways across taxonomic branches and to generate information for kinetic simulations. BIND anticipates the coming large influx of interaction information from high-throughput proteomics efforts including detailed information about post-translational modifications from mass spectrometry. Version 2.0 of the BIND data model is discussed as well as implementation, content and the open nature of the BIND project. The BIND data specification is available as ASN.1 and XML DTD.

Borate-Rhamnogalacturonan II Bonding Reinforced by Ca2+ Retains Pectic Polysaccharides in Higher-Plant Cell Walls1

The extent of in vitro formation of the borate-dimeric-rhamnogalacturonan II (RG-II) complex was stimulated by Ca2+. The complex formed in the presence of Ca2+ was more stable than that without Ca2+. A naturally occurring boron (B)-RG-II complex isolated from radish (Raphanus sativus L. cv Aokubi-daikon) root contained equimolar amounts of Ca2+ and B. Removal of the Ca2+ by trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid induced cleavage of the complex into monomeric RG-II. These data suggest that Ca2+ is a normal component of the B-RG-II complex. Washing the crude cell walls of radish roots with a 1.5% (w/v) sodium dodecyl sulfate solution, pH 6.5, released 98% of the tissue Ca2+ but only 13% of the B and 22% of the pectic polysaccharides. The remaining Ca2+ was associated with RG-II. Extraction of the sodium dodecyl sulfate-washed cell walls with 50 mm trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid, pH 6.5, removed the remaining Ca2+, 78% of B, and 49% of pectic polysaccharides. These results suggest that not only Ca2+ but also borate and Ca2+ cross-linking in the RG-II region retain so-called chelator-soluble pectic polysaccharides in cell walls.

Interstitial cells of Cajal mediate inhibitory neurotransmission in the stomach.

The structural relationships between interstitial cells of Cajal (ICC), varicose nerve fibers, and smooth muscle cells in the gastrointestinal tract have led to the suggestion that ICC may be involved in or mediate enteric neurotransmission. We characterized the distribution of ICC in the murine stomach and found two distinct classes on the basis of morphology and immunoreactivity to antibodies against c-Kit receptors. ICC with multiple processes formed a network in the myenteric plexus region from corpus to pylorus. Spindle-shaped ICC were found within the circular and longitudinal muscle layers (IC-IM) throughout the stomach. The density of these cells was greatest in the proximal stomach. IC-IM ran along nerve fibers and were closely associated with nerve terminals and adjacent smooth muscle cells. IC-IM failed to develop in mice with mutations in c-kit. Therefore, we used W/W(V) mutants to test whether IC-IM mediate neural inputs in muscles of the gastric fundus. The distribution of inhibitory nerves in the stomachs of c-kit mutants was normal, but NO-dependent inhibitory neuro-regulation was greatly reduced. Smooth muscle tissues of W/W(V) mutants relaxed in response to exogenous sodium nitroprusside, but the membrane potential effects of sodium nitroprusside were attenuated. These data suggest that IC-IM play a critical serial role in NO-dependent neurotransmission: the cellular mechanism(s) responsible for transducing NO into electrical responses may be expressed in IC-IM. Loss of these cells causes loss of electrical responsiveness and greatly reduces responses to nitrergic nerve stimulation.