186 research outputs found
Assessment of Hyporheic Exchange at In-stream Restoration Structures on Savage River, Garrett County, Maryland
Previous studies have shown that in-stream restoration structures alter hyporheic exchange dynamics in restored channels; this study assessed hyporheic exchange at a recently constructed stream reach, including the effects of in-stream restoration structures. Hydrometric and thermal data were collected in the streambed near three restoration structures and at a reference site. The hydrometric data indicated that hyporheic flow paths may not have fully developed in the first 16 months following construction; only one in-stream piezometer was unambiguously hydraulically connected to changes in stream stage. Other hydrometric data revealed possible piezometer installations in low permeability materials, potential hydraulic connections to an adjacent wetland or the pre-restoration channel, and a high degree of heterogeneity in both the subsurface material properties and the hyporheic flow patterns. A heat transport model was used to quantify vertical hyporheic fluxes from diurnal temperature fluctuations upstream and downstream of the restoration structures and at the reference site. Fluxes at the reference site were comparable in magnitude to fluxes in the constructed channel, which contrasts a previous study that found enhanced hyporheic exchange near restoration structures. Unfortunately, the sparse instrumentation network at Savage River did not allow for adequate characterization of hyporheic heterogeneities. Future work should include a denser instrumentation network to better characterize flow pattern heterogeneities as well as thorough characterization of subsurface material properties
Shaping the Italian Prehistoric landscapes in a wider process of sea-level changes : interdisciplinary researches and new data
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Implementación de computación de alto rendimiento y programación paralela en códigos computacionales
Measuring utility with diffusion models
The diffusion model (DDM) is a prominent account of how people make decisions. Many of these
decisions involve comparing two alternatives based on differences of perceived stimulus magnitudes,
such as economic values. Here, we propose a consistent estimator for the parameters of a DDM in
such cases. This estimator allows us to derive decision thresholds, drift rates, and subjective percepts
(i.e., utilities in economic choice) directly from the experimental data. This eliminates the need to
measure these values separately or to assume specific functional forms for them. Our method also
allows one to predict drift rates for comparisons that did not occur in the dataset. We apply the
method to two datasets, one comparing probabilities of earning a fixed reward and one comparing
objects of variable reward value. Our analysis indicates that both datasets conform well to the DDM.
Interestingly, we find that utilities are linear in probability and slightly convex in reward
Laterality and fish welfare:A review
Humans interact with fishes in many contexts including aquaculture, scientific study and companion animals. In all of these contexts, fish welfare can be compromised through anthropogenic means. Concern for fish welfare has grown considerably in recent years, with many states and territories now protecting fish through animal welfare regulations. We are not only morally obliged to ensure good welfare of animals in our care, but increasingly required to do so by law. A greater understanding of fish behaviour can lead to the development of welfare indicators. Here we suggest that laterality has wide-spread consequences for fish behaviour and a better understanding of how laterality shapes and interacts with fish behaviour may provide opportunities to enhance fish welfare. Moreover, assessment of laterality through behavioural assays may well be a useful welfare indicator in its own right given the close apparent link between laterality, personality and stress reactivity. Here we review the current research investigating laterality in fishes and highlight instances which may have important consequences for fish welfare
Unveiling the egg microbiota of the loggerhead sea turtle Caretta caretta in nesting beaches of the Mediterranean Sea
Microbes have central roles in the development and health of animals, being the introduction of specific microbial species a potential conservation strategy to protect animals from emerging diseases. Thus, insight into the microbiota of the species and their habitats is essential. In this manuscript, we report for the first time the bacterial composition of all the components (eggshells of hatched and unhatched eggs, internal content of unhatched eggs, intestinal content of hatchling and pipping sea turtles, and sand) of three nesting beaches of Caretta caretta along the Italian coasts of the Mediterranean Sea. The analysis of 26 amplicon samples was carried out using next-generation sequencing analysis, targeting V3–V4 regions of the bacterial 16S rRNA gene. Samples featured mainly Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes, whose percentages depended on the sample type. Our results showed that, although from different sampling sites, the internal content of the unhatched eggs, intestinal content of hatchling and pipping sea turtles share the microbiota, which was yet different from that of eggshells and sand of the same nesting beach. This study suggests the maternal and environmental influence alongside a protective role of eggshells in shaping the egg microbiota of Caretta caretta sea turtles
Unveiling the egg microbiota of the loggerhead sea turtle <i>Caretta caretta</i> in nesting beaches of the Mediterranean Sea
Microbes have central roles in the development and health of animals, being the introduction of specific microbial species a potential conservation strategy to protect animals from emerging diseases. Thus, insight into the microbiota of the species and their habitats is essential. In this manuscript, we report for the first time the bacterial composition of all the components (eggshells of hatched and unhatched eggs, internal content of unhatched eggs, intestinal content of hatchling and pipping sea turtles, and sand) of three nesting beaches of Caretta caretta along the Italian coasts of the Mediterranean Sea. The analysis of 26 amplicon samples was carried out using next-generation sequencing analysis, targeting V3-V4 regions of the bacterial 16S rRNA gene. Samples featured mainly Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes, whose percentages depended on the sample type. Our results showed that, although from different sampling sites, the internal content of the unhatched eggs, intestinal content of hatchling and pipping sea turtles share the microbiota, which was yet different from that of eggshells and sand of the same nesting beach. This study suggests the maternal and environmental influence alongside a protective role of eggshells in shaping the egg microbiota of Caretta caretta sea turtles
The archaeological evidence of sea level change in the Mediterranean: guidelines and reappraisals
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Numerical modelling of stress-strain analysis at an underground quarry in the Apuan Alps marble district (Italy)
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