356 research outputs found

    A Neo-Searlean Theory of Intentionality

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    This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.I present Searle’s theory of intentionality and defend it against some objections. I then significantly extend his theory by exposing and incorporating an ambiguity in the question as to what an intentional state is about as between a subjective and an objective reading of the question. Searle implicitly relies on this ambiguity while applying his theory to a solution to the problem of substitution in propositional attitudes, but his failure to explicitly accommodate the ambiguity undermines his solution. My extension of his theory succeeds. I also indicate how the new theory can be deployed to resolve other outstanding problems.ECU/Cambridge open access publishing agreemen

    Assessing the relevance of different sources of variability on the survival of foodborne pathogens: stress adaptation against genetic heterogeneities

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    [SPA] La evaluación de riesgos microbianos es crucial para proteger la salud pública, así como para que la cadena de suministro de alimentos sea eficiente. La evaluación debe considerar varias fuentes variabilidad en la respuesta microbiana, tales como la adaptación al estrés y las heterogeneidades genéticas, ya que éstas pueden afectar la supervivencia, el crecimiento y la virulencia de los patógenos alimentarios influyendo a su capacidad para causar enfermedades en humanos o alteraciones en los alimentarios. Actualmente existen grandes lagunas de conocimiento en cuanto a la variabilidad de la respuesta microbiana, por lo que su elucidación es esencial para una estimación precisa del riesgo, así como para el desarrollo de medidas de control eficaces. En base a esto, esta tesis de doctorado tiene como objetivo evaluar y comparar la importancia de la adaptación al estrés y las heterogeneidades genéticas en los microorganismos para la supervivencia de las bacterias a los tratamientos térmicos. En el Capítulo I se estudia la inactivación térmica de dos cepas de Salmonella (Salmonela Enteritidis CECT4300 y Senftenberg CECT4565) tanto en condiciones isotérmicas como dinámicas. Para los tratamientos isotérmicos, se encontró que S. Senftenberg era mucho más resistente que S. Enteritidis (por un factor de aproximadamente 10). También observamos diferencias cualitativas: las curvas de supervivencia isotermas de la cepa de S. Senftenberg fueron de tipo Weibull, mientras que el modelo Bigelow (lineal) fue capaz de describir la respuesta de S. Enteritidis. Así mismo, los modelos basados en experimentos isotérmicos fueron capaces de describir la inactivación dinámica de S. Senftenberg, mientras que S. Enteritidis necesitó de un modelo dinámico que consideraba la aclimatación del estrés. El estudio destaca que, además de la variabilidad cuantitativa, la inactividad microbiana también tiene una componente cualitativa. Esto enfatiza la importancia de considerar diferentes hipótesis de modelo para las condiciones isotérmicas y dinámicas. El Capítulo II va más allá en la inactivación térmica de Salmonella spp. centrándose en la importancia de la variabilidad fenotípica en la evaluación del riesgo microbiano. Esta fuente de variabilidad incluye las diferencias en el estado fisiológico de diferentes células de las mismas especies bacterianas debido a una exposición previa a diferentes entornos. Se estudió tanto el impacto de las condiciones de pre-cultivo subóptimas en la resistencia térmica de las mismas dos cepas de Salmonella como el efecto de un choque ácido. Los resultados muestran que la variabilidad fenotípica también es dependiente de la cepa. Para la cepa de Salmonella altamente resistente (S. Senftenberg), se observó una reducción de la resistencia térmica con respecto a las condiciones óptimas de incubación. Por otro lado, las condiciones de incubación subóptimas tuvieron el efecto opuesto en la cepa de referencia (S. Enteritidis), aumentando su resistencia térmica a través de la inducción de mecanismos de resistencia cruzada. En base a estos resultados, el estudio sugiere que la variabilidad fenotípica debería ser un aspecto central en la microbiología predictiva y la evaluación de riesgos, e ilustra un ejemplo hipotético de incorporación de esta fuente de variabilidad en el análisis de riesgos vinculando las condiciones pre-cultivo al origen de la contaminación bacteriana. El Capítulo III utiliza un organismo modelo (Bacillus subtilis) para profundizar en el estudio de las diferencias entre la inactivación bacteriana bajo condiciones isotermas y dinámicas. Con el objetivo de relacionar la respuesta microbiana observada a nivel poblacional con información a nivel molecular, se realizaron experimentos utilizando tanto una cepa silvestre como un mutante “sigB null”. Se observaron curvas de supervivencia con una curvatura hacia arriba, que a menudo se atribuye a la heterogeneidad en la resistencia térmica (hipótesis vitalística). Sin embargo, las curvas de inactivación tras la aplicación de un pretratamiento fueron log-lineales, indicando la adaptación dinámica al estrés durante el tratamiento isotérmico como una posible explicación de la curvatura observada. Esta interpretación de los resultados permite definir, en base a resultados isotermos, límites para la adaptación microbiana que se pueda desarrollar durante un tratamiento dinámico. Por lo tanto, este estudio proporciona una interpretación alternativa de las curvas de supervivencia bajo condiciones isotermas que podría llegar a mejorar nuestra capacidad de predecir la respuesta microbiana durante los tratamientos de pasteurización. [ENG] Microbial risk assessment is crucial for protecting public health and the food supply chain. Sources of variability in microorganisms, such as stress adaptation and genetic heterogeneities, can affect the survival, growth and virulence of microorganisms, and their ability to cause disease or food spoilage. There are currently large knowledge gaps regarding variability of the microbial response, and understanding it is essential for accurately estimating potential risks and to develop effective control measures. In light of this, this PhD thesis aims to compare and evaluate the importance of stress adaptation and genetic heterogeneities in microorganisms for the survival of bacteria to thermal treatments. Chapter I discusses the thermal inactivation of two Salmonella strains (Salmonella Enteritidis CECT4300 and Salmonella Senftenberg CECT4565) under both isothermal and dynamic conditions. For isothermal treatments, S. Senftenberg was found to be much more resistant than S. Enteritidis (by approximately a factor of 10). We also observed qualitative differences, with the inactivation models used to describe the response of S. Senftenberg were weibullian, while the Bigelow model was successful in describing the isothermal response of S. Enteritidis. Models based on isothermal experiments were able to describe dynamic inactivation of S. Senftenberg, while S. Enteritidis required a dynamic model that considered stress acclimation. The study highlights that, besides quantitative, variability in microbial inactivation is also qualitative. This underlies importance of considering different model hypotheses for both isothermal and dynamic conditions. Chapter II goes further in the thermal inactivation of Salmonella spp. focusing on the importance of phenotypic variability in microbial risk assessment, which refers to the physiological differences of cells of the same bacterial species due to prior exposure to different environments. The impact of sub-optimal pre-culture conditions or the application of an acid shock on the thermal resistance of the same two Salmonella strains was studied, founding that phenotypic variability is also strain-dependent. For the highly resistant strain (S. Senftenberg), the conditions tested resulted in a reduction of thermal resistance with respect to optimal incubation conditions. On the other hand, sub-optimal incubation conditions had the opposite effect on the reference strain (S. Enteritidis), increasing its thermal resistance through the induction of cross-resistance mechanisms. The study suggests that phenotypic variability should be a main focus in predictive microbiology and risk assessment, and illustrates a hypothetical example of how this could be achieved in practice by linking pre-incubation conditions to the origin of bacterial contamination. Chapter III uses a common model organism (Bacillus subtilis) to further study the differences between isothermal and dynamic bacterial inactivation. To link differences in the response to molecular mechanisms, experiments were made using both a wild type strain and a marker-free sigB null mutant. Survivor curves with an upward curvature were observed, which is often attributed to heterogeneity in thermal resistance (vitalistic hypothesis). However, a pretreatment resulted in log-linear survivor curves, indicating dynamic stress adaptation during the isothermal treatment as a possible explanation for the upward curvature. Based on this hypothesis, bounds were defined based on isothermal experiments to account for acclimation under dynamic conditions. The study provides an alternative interpretation for survivor curves, which can improve predictions of microbial response during pasteurization treatments.Escuela Internacional de Doctorado de la Universidad Politécnica de CartagenaUniversidad Politécnica de CartagenaPrograma de Doctorado en Técnicas Avanzadas en Investigación y Desarrollo Agrario y Alimentari

    A New Economic Era in Computer Science: DNA Vs Quantum Computing

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    The increasing rate of growth both of science and technology in our era, renders the forecasts for the development course of each technology, very significant for the strategic development designer of any organism, either this concerns an enterprise or a state or a union of states. Such a technology is the computer technology, which is currently to the limit of its current possibilities and is being prepared to pass into a new era and create a new economic environment. The silicon technology, because of its constructional restrictions, cannot maintain the existing growth rate for more than one decade. “Spintronics” or “molecular electronics” can constitute transient technologies, but the radical change will be the transition from serial to parallel calculating process.Aim of this work is to constitute a useful tool for the forecast of development of the subversive technologies that will bring us to a new era of computer science. DNA computing and Quantum computing are considered as such technologies. The use of such a forecast may result in dramatic changes in the economic map of the companies engaged in information technology, since it will allow an early placement of them in upcoming competitive race

    The Scontrone turtles – A new insular testudinoid fauna from the late Miocene of the Central Mediterranean

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    We here describe a small turtle assemblage originating from the early Tortonian (late Miocene) palaeois-land of Scontrone, central Italy, a locality previously known mostly for its endemic mammals and giantbirds, which were otherwise shared only with the Gargano localities, another fossiliferous area belongingto the same palaeobioprovince. The fossil turtle remains from Scontrone are referred to the geoemydidMauremyssp. and a so far unidentified large-sized testudinid. The biogeographic origins of theScontrone insular chelonians are discussed. The Scontrone geoemydid adds to the known occurrencesofMauremysin the late Miocene of the Mediterranean. The Scontrone large tortoise represents the oldestknown Mediterranean insular testudinid, predating significantly the well-known Quaternary endemicisland tortoises of the area

    Plasma Exchange for the Recurrence of Primary Focal Segmental Glomerulosclerosis in Adult Renal Transplant Recipients: A Meta-Analysis

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    Background. Posttransplant recurrence of primary focal segmental glomerulosclerosis (rFSGS) in the form of massive proteinuria is not uncommon and has detrimental consequences on renal allograft survival. A putative circulating permeability factor has been implicated in the pathogenesis leading to widespread use of plasma exchange (PLEX). We reviewed published studies to assess the role of PLEX on treatment of rFSGS in adults. Methods. Eligible manuscripts compared PLEX or variants with conventional care for inducing proteinuria remission (PR) in rFSGS and were identified through MEDLINE and reference lists. Data were abstracted in parallel by two reviewers. Results. We detected 6 nonrandomized studies with 117 cases enrolled. In a random effects model, the pooled risk ratio for the composite endpoint of partial or complete PR was 0,38 in favour of PLEX (95% CI: 0,23–0,61). No statistical heterogeneity was observed among included studies (I2=0%, p = 0,42). On average, 9–26 PLEX sessions were performed to achieve PR. Renal allograft loss due to recurrence was lower (range: 0%–67%) in patients treated with PLEX. Conclusion. Notwithstanding the inherent limitations of small, observational trials, PLEX appears to be effective for PR in rFSGS. Additional research is needed to further elucidate its optimal use and impact on long-term allograft survival

    A review of the fossil record of old world turtles of the clade pan-trionychidae

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    Turtles of the clade Pan-Trionychidae have a rich fossil record in the Old World, ranging from the Early Cretaceous (Hauterivian) to the Holocene. The clade most probably originated in Asia during the Early Cretaceous but spread from there to the Americas and Europe by the Late Cretaceous, to India and Australia by the Eocene, and to Afro-Arabia by the Neogene. The presence of a single pan-cyclanorbine in the Late Cretaceous (Maastrichtian) of Asia provides a minimum estimate for the age of the trionychid crown. As preserved, diversity was relatively high in Asia during the Late Cretaceous, but the subsequent, strong decline is likely a preservational bias, as extant faunas are relatively rich, especially throughout Asia. The range of trionychids contracted southward in Europe over the course of the Neogene, and the group is now locally extirpated. The group is now similarly absent from Arabia and Australia. A taxonomic review of the 180 named Old World taxa finds 42 nomina valida, 38 nomina invalida, 88 nomina dubia, 11 nomina nuda, and 1 nomen suppressum

    Crushed but not lost: a colubriform snake (Serpentes) from the Miocene Swiss Molasse, identified through the use of micro-CT scanning technology

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    An incomplete postcranial skeleton of a snake from the middle Miocene of the Swiss Molasse in Käpfnach mine, near Zurich, Switzerland, is described in this paper. The skeleton is rather crushed and resting on a block of coal, with only some articulated vertebrae partially discerned via visual microscopy. We conducted micro-CT scanning in the specimen and we digitally reconstructed the whole preserved vertebral column, allowing a direct and detailed observation of its vertebral morphology. Due to the flattened nature of the fossil specimen, several individual vertebral structures are deformed, not permitting thus a secure precise taxonomic identification. Accordingly, we only refer the specimen to as Colubriformes indet. Nevertheless, this occurrence adds to the exceedingly rare fossil record of snakes from Switzerland, which had so far been formally described solely from three other Eocene and Miocene localities

    Fossil lizards and snakes from Ano Metochi – a diverse squamate fauna from the latest Miocene of northern Greece

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    We here describe a new squamate fauna from the late Miocene (Messinian, MN 13) of Ano Metochi, northern Greece. The lizard fauna of Ano Metochi is here shown to be rather diverse, consisting of lacertids, anguids, and potential cordylids, while snakes are also abundant, consisting of scolecophidians, natricines and at least two different colubrines. If our identification is correct, the Ano Metochi cordylids are the first ones identified from Greece and they are also the youngest representatives of this group in Europe. A previously described scincoid from the adjacent locality of Maramena is here tentatively also referred to cordylids, strengthening a long term survival of this group until at least the latest Miocene. The scolecophidian from Ano Metochi cannot be attributed with certainty to either typhlopids or leptotyphlopids, which still inhabit the Mediterranean region. The find nevertheless adds further to the poor fossil record of these snakes. Comparison of the Ano Metochi herpetofauna with that of the adjacent locality of Maramena reveals similarities, but also striking differences among their squamate compositions

    Late Paleogene herpetofaunas from the crossroads between two continents – new amphibian and reptile remains from the Oligocene of southern Balkans and Anatolia

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    We describe here new amphibian and reptile remains from three Oligocene localities of Turkey. Two of the localities (Kavakdere and Kocayarma) are situated in southeastern Europe and the other one (Kargi 2) in Anatolia, both areas where Oligocene herpetofauna is practically almost unknown. The material consists of albanerpetontids, pelobatid anurans, turtles, crocodylians, lacertids, scinciformatans, anguines, and “tropidophiids”. Albanerpetontids are for the first time identified in southeastern Europe, with the material being reminiscent of the younger species Albanerpeton inexpectatum Estes & Hoffstetter, 1976; the material potentially represents the oldest record of that species. Pelobatids, scinciformatans, and “tropidophiids” represent the oldest occurrences of these clades in the northeastern Mediterranean. The anguine genus Ophisaurus Daudin, 1803 is identified for the first time in the Paleogene of Eastern Europe. The “tropidophiids” are referred to two genera, Falseryx Szyndlar & Rage, 2003 and tentatively also to Platyspondylia Rage, 1974, with the latter having been so far exclusively known from western and central Europe. The role of a potential southern dispersal route of taxa among Asia and Europe, involving the area of southern Balkans and Anatolia, similarly to what has been recently demonstrated for mammals, is highlighted also for amphibians and reptiles
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