Effects of ocean acidification on the brown alga "Padina pavonica": decalcification due to acute and chronic events

[EN] Since the industrial revolution, anthropogenic CO2 emissions have caused ocean acidification, which particularly affects calcified organisms. Given the fan-like calcified fronds of the brown alga Padina pavonica, we evaluated the acute (shortterm) effects of a sudden pH drop due to a submarine volcanic eruption (October 2011–early March 2012) affecting offshore waters around El Hierro Island (Canary Islands, Spain). We further studied the chronic (long-term) effects of the continuous decrease in pH in the last decades around the Canarian waters. In both the observational and retrospective studies (using herbarium collections of P. pavonica thalli from the overall Canarian Archipelago), the percent of surface calcium carbonate coverage of P. pavonica thalli were contrasted with oceanographic data collected either in situ (volcanic eruption event) or from the ESTOC marine observatory data series (herbarium study). Results showed that this calcified alga is sensitive to acute and chronic environmental pH changes. In both cases, pH changes predicted surface thallus calcification, including a progressive decalcification over the last three decades. This result concurs with previous studies where calcareous organisms decalcify under more acidic conditions. Hence, Padina pavonica can be implemented as a bio-indicator of ocean acidification (at short and long time scales) for monitoring purposes over wide geographic ranges, as this macroalga is affected and thrives (unlike strict calcifiers) under more acidic conditions

A randomized, double-blind, placebo-controlled pilot study of naltrexone in outpatients with bipolar disorder and alcohol dependence.

BACKGROUND: Alcohol dependence is extremely common in patients with bipolar disorder and is associated with unfavorable outcomes including treatment nonadherence, violence, increased hospitalization, and decreased quality of life. While naltrexone is a standard treatment for alcohol dependence, no controlled trials have examined its use in patients with co-morbid bipolar disorder and alcohol dependence. In this pilot study, the efficacy of naltrexone in reducing alcohol use and on mood symptoms was assessed in bipolar disorder and alcohol dependence. METHODS: Fifty adult outpatients with bipolar I or II disorders and current alcohol dependence with active alcohol use were randomized to 12 weeks of naltrexone (50 mg/d) add-on therapy or placebo. Both groups received manual-driven cognitive behavioral therapy designed for patients with bipolar disorder and substance-use disorders. Drinking days and heavy drinking days, alcohol craving, liver enzymes, and manic and depressed mood symptoms were assessed. RESULTS: The 2 groups were similar in baseline and demographic characteristics. Naltrexone showed trends (p < 0.10) toward a greater decrease in drinking days (binary outcome), alcohol craving, and some liver enzyme levels than placebo. Side effects were similar in the 2 groups. Response to naltrexone was significantly related to medication adherence. CONCLUSIONS: Results suggest the potential value and acceptable tolerability of naltrexone for alcohol dependence in bipolar disorder patients. A larger trial is needed to establish efficacy.

Elevated albumin in retinas of monkeys with experimental glaucoma.

PURPOSE: To establish the identity of a prominent protein, approximately 70 kDa, that is markedly increased in the retina of monkeys with experimental glaucoma compared with the fellow control retina, the relationship to glaucoma severity, and its localization in the retina. METHODS: Retinal extracts were subjected to 2-D gel electrophoresis to identify differentially expressed proteins. Purified peptides from the abundant 70 kDa protein were analyzed and identified by liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) separation, and collision-induced dissociation sequencing. Protein identity was performed on MASCOT (Matrix Science, Boston, MA) and confirmed by Western blot. The relationship between the increase in this protein and glaucoma severity was investigated by regression analyses. Protein localization in retina was evaluated by immunohistochemistry with confocal imaging. RESULTS: The abundant protein was identified as Macaca mulatta serum albumin precursor (67 kDa) from eight non-overlapping proteolytic fragments, and the identity was confirmed by Western blot. The average increase in retinal albumin content was 2.3 fold (P = 0.015). In glaucoma eyes, albumin was localized to some neurons of the inner nuclear layer, in the inner plexiform layer, and along the vitreal surface, but it was only found in blood vessels in control retinas. CONCLUSIONS: Albumin is the abundant protein found in the glaucomatous monkey retinas. The increased albumin is primarily localized to the inner retina where oxidative damage associated with experimental glaucoma is known to be prominent. Since albumin is a major antioxidant, the increase of albumin in the retinas of eyes with experimental glaucoma may serve to protect the retina against oxidative damage.

Rationale for reading fluconazole MICs at 24 hours rather than 48 hours when testing Candida spp. by the CLSI M27-A2 standard method.

We investigated if CLSI M27-A2 Candida species breakpoints for fluconazole MIC are valid when read at 24 h. Analysis of a data set showed good correlation between 48- and 24-h MICs, as well as similar outcomes and pharmacodynamic efficacy parameters, except for isolates in the susceptible dose-dependent category, such as Candida glabrata.

The Chemical Mechanism of a Brown-Rot Decay Mimtic System and its Application in Paper Recycling Processes

This work is aimed at improving our current knowledge of the non-enzymatic inecl~anisins involved in brown-rot decay, as well as the exploration of potential applications of a brown-rot mimetic model system in paper recycling processes. The study was divided into two parts. The first part focussed on the chemical mechanisms involved in chelation and reduction of iron by a low molecular weight chelator (isolated from the brown-rot fungus Gloeophyllz~m tmbeum) and its model compound 2,3- dihydroxybenzoic acid (2,3-DHBA). Chelation as well as free radical generation mediated by this system were studied by ESR measurement. The results indicate that the effects of the chelator/iron ratio, the pH, and other reaction parameters on hydroxyl radical generation by a Fenton type system could be determined using ESR spin-trapping techniques. The results also support the hypothesis that superoxide radicals are involved in the chelator-mediated Fenton process. In the second part of the study, the effect of a chelator-mediated Fenton system for the improvement of deinking efficiency and the n~odification of fiber and paper properties was studied. For the deinking study, copy paper was laser printed with an identical standard pattern. Then repulping and flotation operations were performed to remove ink particles. Under properly controlled deinking conditions, the chelator mediated treatment (CMT) resulted in a reduction in dirt count over that of conventional deinking procedures with no significant loss of pulp strength. To study the effect of the chelator system treatment on the quality of pulp with different fines content, a fully bleached hardwood kraft pulp was beaten to different freeness levels and treated with the chelator-mediated free radical system. The result shows that virgin fiber and heavily beaten fiber respond differently to the free radical treatment. Unbeaten fibers become more flexible and easier to collapse after free radical treatment, while beaten fibers show a reduction in fines and small materials after mild free radical treatment.

Organizational perspectives on the management and evaluation of large -scale multicenter controlled clinical trials: An exploratory study of participation in the beta -blocker heart attack trial

A review of literature related to appointment-keeping served as the basis for the development of an organizational paradigm for the study of appointment-keeping in the Beta-blocker Heart Attack Trial (BHAT). Features of the organizational environment, demographic characteristics of BHAT enrollees, organizational structure and processes and previous organizational performance variables were measured so as to provide exploratory information relating to the appointment-keeping behavior of 3,837 participants enrolled at thirty-two Clinical Centers. Results suggest that the social context of individual behavior is an important consideration for the understanding of patient compliance. In particular, the degree to which previous organizational performance--as measured by obtaining recruitment goals--and the ability to utilize resources had particularly strong bivariate associations with appointment-keeping. Implications for future theory development, research and practical implications were provided as was a suggestion for the development of multidisciplinary research efforts conducted within the context of Centers for the study and application of adherence behaviors. ^

Spectral reflectance library of selected biotic and abiotic coral reef features in Glovers Reef, Belize

Underwater spectral reflectance was measured for selected biotic and abiotic coral reef features of Glovers Reef, Belize from March 6 - 10, 2005. Spectral reflectance's of 63 different benthic types were obtained in-situ. An Ocean Optics USB2000 spectrometer was deployed in an custom made underwater housing with a 0.5 m fiber-optic probe mounted next to an artificial light source. Spectral readings were collected with the probe (bear fibre) about 5 cm from the target to ensure that the target would fill the field of view of the fiber optic (FOV diameter ~4.4 cm), as well as to reduce the attenuating effect of the intermediate water (Roelfsema et al., 2006). Spectral readings included for one target included: 1 reading of the covered spectral fibre to correct for instrument noise, 1 reading of spectralon panel mounted on divers wrist to measure incident ambient light, and 8 readings of the target. Spectral reflectance was calculated for each target by first subtracting the instrument noise reading from each other reading. The corrected target readings were then divided by the corrected spectralon reading resulting in spectral reflectance of each target reading. An average target spectral reflectance was calculated by averaging the eight individual spectral reflectance's of the target. If an individual target spectral reflectance was visual considered an outlier, it was not included in the average spectral reflectance calculation. See Roelfsema at al. (2006) for additional info on the methodology of underwater spectra collection.

Otros espacios, otros lugares y segregaciones socio culturales en la narrativa de John Steinbeck

Fil: Car, Nora Marcela. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

El valor del arte. John Ruskin

Fil: Bertucci, Alejandra Isabel. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Crítica a la interpretación jamesiana de las tesis realistas en Ferdiand Schiller y John Dewey

Fil: Di Berardino, María Aurelia. Universidad Nacional de La Plata. Facultad de Humanidades y Ciencias de la Educación; Argentina.

Una reconstrucción de la lógica de la investigación de John Dewey

El objetivo de esta tesis es ofrecer una reconstrucción de la teoría de la investigación de John Dewey, prestando atención a sus antecedentes en los escritos del padre del pragmatismo, Charles Sanders Peirce, y a algunas derivaciones de tal teoría en la teoría de la argumentación contemporánea y en los estudios sociales de la ciencia. La misma está dividida en tres partes dedicadas a (I) explorar algunos antecedentes de la teoría de la investigación de Dewey, (II) desarrollar y analizar críticamente los aspectos centrales de tal teoría y, por último, (III) seguir la pista de algunas de sus derivaciones. El punto de partida es el análisis de la concepción de la lógica de la investigación de Peirce, tal como éste la fuera construyendo a partir de su crítica a la filosofía moderna. Ofrecemos una reconstrucción de las ideas de Peirce que permite dar cuenta de que, pese a las importantes diferencias entre las ideas de Peirce y Dewey, los desarrollos de este último pueden ser considerados como una prosecución, en nuevas y profundas direcciones, de algunas de las ideas más destacadas del primero y que constituyen, por ello, una lectura posible de algunos de los escritos más destacados de Peirce. En la segunda parte, la central de esta tesis, se aborda la teoría de la investigación de Dewey. En este marco, se reconstruye la teoría de la experiencia de Dewey, que constituye, como se argumenta, un verdadero punto de partida para la teoría de la investigación. Se argumenta que la teoría de la experiencia de Dewey puede ser considerada como un análisis de las consecuencias para la filosofía de algunos de los resultados más influyentes en el campo de la biología, la psicología y la antropología social en relación con la comprensión de los seres humanos. Se reconstruye también la teoría de la investigación que, al ser comprendida como una forma de la experiencia, permite dar cuenta del carácter mediador y transformacional del conocimiento. Se analizan, asimismo, las consecuencias que para la comprensión de la lógica se siguen de dicha concepción y se argumenta que, pese a lo que Peirce y algunos intérpretes contemporáneos sostienen, la lógica de Dewey puede ser considerada una verdadera lógica. Además, en esta segunda parte se analiza la concepción deweyana de la valoración y se reconstruye una perspectiva acerca de la interdependencia del conocimiento y los valores. Asimismo, se argumenta que, y contra lo que las críticas de Horkheimer y Adorno sugieren, la teoría de la valoración de Dewey tiene un potencial crítico que permite plantear y abordar el problema de los fines de la acción y, en especial, los de esa acción cognitiva a la que llamamos ciencia. En la tercera y última parte de esta tesis se abordan algunas de las derivaciones de la teoría de la investigación de Dewey. En primer lugar, se exploran las relaciones entre la propuesta de Dewey y la de uno de los más destacados representantes de la teoría de la argumentación contemporánea, a saber, Stephen Toulmin. Se muestra que en la obra de este último puede identificarse una dimensión pragmatista y deweyana. En segundo lugar, se aborda la cuestión de la relación entre la teoría de la investigación de Dewey y el giro hacia las prácticas de los estudios sociales de la ciencia. En particular, se analizan algunos aspectos de la obra de Bruno Latour y de la de Karin Knorr Cetina, mostrando las profundas e interesantes continuidades que suponen con el trabajo de Dewey. Además, se aborda un problema fuertemente discutido en el ámbito de la sociología del conocimiento, a saber, el problema de la reflexividad de los estudios de la ciencia, con el objetivo de ofrecer una mirada deweyana sobre tal cuestión, lo que permitirá sostener una interpretación de la filosofía del conocimiento de Dewey como filosofía política de la ciencia