Determinación de la edad y el crecimiento por esclerocronología en la tortuga boba marina Caretta caretta del mar Mediterráneo

Skeletochronology was applied to humerus bones to assess the age and growth rates of loggerhead sea turtles (Caretta caretta) in the Mediterranean Sea. Fifty-five dead turtles with curved carapace lengths (CCL) ranging from 24 to 86.5 cm were collected from the central Mediterranean. Sections of humeri were histologically processed to analyze annual growth marks. Two approaches were used to estimate the somatic growth in the form of a von Bertalanffy growth function. The first approach was based on calculating the total number of growth marks, which corresponds to the age of turtles at death. The second approach estimates the carapace length at old growth marks in order to provide the growth rate of each turtle. The observed individual growth rates ranged from 1.4 to 6.2 cm yr–1, and showed both elevated inter- and intra-individual variability possibly related to the environmental variability experienced by turtles during their lifetime. Both approaches gave similar results and suggest that Mediterranean loggerhead turtles take 14.9 to 28.5 years to reach a CCL of 66.5 to 84.7 cm. This size corresponds to the average size of nesting females found in the most important Mediterranean nesting sites and can be considered the approximate size at maturity.La esclerocronología se aplicaba a los huesos de los húmeros para determinar la edad y las tasas de crecimiento de la tortuga boba Caretta caretta del Mediterráneo. Cincuenta y cinco tortugas bobas muertas de 24 a 86.5 cm de longitud de la curvatura del caparazón (CCL) fueron recogidas del Mediterráneo central. Secciones de los húmeros fueron procesados histológicamente para analizar las marcas anuales de crecimiento. Se aplicaron dos aproximaciones para determinar el crecimiento somático utilizando la función de crecimiento de von Bertalanffy. La primera aproximación se basaba en el número total de marcas de crecimiento, correspondiendo a la edad de las tortugas en el momento de la muerte. La segunda aproximación era una estimación de la longitud del caparazón en las marcas de crecimiento más antiguas, con la intención de saber la tasa de crecimiento de cada tortuga. Las tasas de crecimiento individual observadas, oscilaban entre 1.4 y 6.2 cm año–1, mostrando una elevada diversidad individual intra e interanual, posiblemente ligada a la variabilidad ambiental experimentada por las tortugas bobas durante su vida. Ambas aproximaciones dieron resultados similares y sugieren que la tortuga mediterránea tarda 14.5-28.5 años en alcanzar un tamaño de 66.5-84.7 cm de CCL. Este tamaño corresponde al tamaño medio de las tortugas bobas hembras nidificantes, encontradas en la mayoría de lugares nidificantes del Mediterráneo y puede ser considerado el tamaño aproximado de la madurez

Age and growth determination by skeletochronology in loggerhead sea turtles (<i>Caretta caretta</i>) from the Mediterranean Sea

La esclerocronología se aplicaba a los huesos de los húmeros para determinar la edad y las tasas de crecimiento de la tortuga boba Caretta caretta del Mediterráneo. Cincuenta y cinco tortugas bobas muertas de 24 a 86.5 cm de longitud de la curvatura del caparazón (CCL) fueron recogidas del Mediterráneo central. Secciones de los húmeros fueron procesados histológicamente para analizar las marcas anuales de crecimiento. Se aplicaron dos aproximaciones para determinar el crecimiento somático utilizando la función de crecimiento de von Bertalanffy. La primera aproximación se basaba en el número total de marcas de crecimiento, correspondiendo a la edad de las tortugas en el momento de la muerte. La segunda aproximación era una estimación de la longitud del caparazón en las marcas de crecimiento más antiguas, con la intención de saber la tasa de crecimiento de cada tortuga. Las tasas de crecimiento individual observadas, oscilaban entre 1.4 y 6.2 cm año–1, mostrando una elevada diversidad individual intra e interanual, posiblemente ligada a la variabilidad ambiental experimentada por las tortugas bobas durante su vida. Ambas aproximaciones dieron resultados similares y sugieren que la tortuga mediterránea tarda 14.5-28.5 años en alcanzar un tamaño de 66.5-84.7 cm de CCL. Este tamaño corresponde al tamaño medio de las tortugas bobas hembras nidificantes, encontradas en la mayoría de lugares nidificantes del Mediterráneo y puede ser considerado el tamaño aproximado de la madurez

influence of mechanical parameters on non linear static analysis of masonry buildings a relevant case study

Abstract In seismic zones, suitable procedures to assess the seismic vulnerability of existing buildings are necessary also in view of optimal planning of interventions. Starting from the agreement between the Municipality of Florence and the Department of Civil and Industrial Engineering of the University of Pisa, a research program is ongoing, devoted to setup a simplified, fast but reliable procedure for the evaluation of seismic performance of masonry buildings. In this paper, a simplified non-linear pushover type method for the verification of unreinforced multi-story masonry buildings with both deformable and non-deformable slabs is presented, starting from some of the basic assumptions of the POR method. Various tests on the procedure show that the method is able to give results that are comparable with those obtained by the classical pushover analysis performed on equivalent frame models. The intuitiveness of the method and the low computational effort required by the new algorithm allow the evaluation of the sensitivity of non-linear static analysis regarding the definition of mechanical parameters. In particular, the relevant influence of the modulus of elasticity as well as the ultimate inter-story displacement assumed for masonry walls on the assessment of seismic performance are discussed in detail. The results are presented for a significant case study, the Primary School "G. Carducci" in Florence, a four-story masonry building, with a horseshoe layout where lateral appendixes detached from the central block

A new system for quantitative evaluation of infant gaze capabilities in a wide visual field.

Background: The visual assessment of infants poses specific challenges: many techniques that are used on adults are based on the patient’s response, and are not suitable for infants. Significant advances in the eye-tracking have made this assessment of infant visual capabilities easier, however, eye-tracking still requires the subject’s collaboration, in most cases and thus limiting the application in infant research. Moreover, there is a lack of transferability to clinical practice, and thus it emerges the need for a new tool to measure the paradigms and explore the most common visual competences in a wide visual field. This work presents the design, development and preliminary testing of a new system for measuring infant’s gaze in the wide visual field called CareToy C: CareToy for Clinics. Methods: The system is based on a commercial eye tracker (SmartEye) with six cameras running at 60 Hz, suitable for measuring an infant’s gaze. In order to stimulate the infant visually and audibly, a mechanical structure has been designed to support five speakers and five screens at a specific distance (60 cm) and angle: one in the centre, two on the right-hand side and two on the left (at 30° and 60° respectively). Different tasks have been designed in order to evaluate the system capability to assess the infant’s gaze movements during different conditions (such as gap, overlap or audiovisual paradigms). Nine healthy infants aged 4–10 months were assessed as they performed the visual tasks at random. Results: We developed a system able to measure infant’s gaze in a wide visual field covering a total visual range of ±60° from the centre with an intermediate evaluation at ±30°. Moreover, the same system, thanks to different integrated software, was able to provide different visual paradigms (as gap, overlap and audio-visual) assessing and comparing different visual and multisensory sub-competencies. The proposed system endowed the integration of a commercial eye-tracker into a purposive setup in a smart and innovative way. Conclusions: The proposed system is suitable for measuring and evaluating infant’s gaze capabilities in a wide visual field, in order to provide quantitative data that can enrich the clinical assessment

shear modulus of masonry walls a critical review

Abstract In the assessment of seismic performance of masonry buildings, the proper definition of mechanical parameters of masonry, the shear modulus in particular, is a critical issue. Moreover, considering that existing buildings are characterized by several masonry types, depending on the material as well as on the texture, mechanical parameters can vary in a very wide range, also because they depend on many other parameters and in particular on the integrity of the walls and on the stress level. Although the in situ or laboratory experimental evaluation of the G modulus has been the subject of a wide literature concerning flat jacks, diagonal and single compression and shear-compression test results, its outcomes are often contradictory. In effect, values given by different studies often differ significantly, even for the same class of masonry. Since the intrinsic scattering of the parameter is not sufficient by itself to justify the huge variability of the results, a critical discussion of the results as well as of the individual test arrangements is necessary to make the background more reliable, also in view of better addressing further studies- A huge database has been setup combining masonry test results available in the relevant scientific literature with the test results obtained in the framework of the in situ experimental campaign carried out by the authors for the assessment of seismic vulnerability of masonry school buildings in the Municipality of Florence. The analysis of the database underlines that values of the shear modulus G, which is a fundamental parameter for the definition of capacity curve for walls commonly used in non-linear static analysis, are extremely scattered. Testing methodology and arrangement are discussed and a possible procedure is proposed to arrive to sounder estimations of relevant mechanical parameter of existing building masonry

Massage accelerates brain development and the maturation of visual function

Environmental enrichment (EE) was shown recently to accelerate brain development in rodents. Increased levels of maternal care, and particularly tactile stimulation through licking and grooming, may represent a key component in the early phases of EE. We hypothesized that enriching the environment in terms of body massage may thus accelerate brain development in infants. We explored the effects of body massage in preterm infants and found that massage accelerates the maturation of electroencephalographic activity and of visual function, in particular visual acuity. In massaged infants, we found higher levels of blood IGF-1. Massage accelerated the maturation of visual function also in rat pups and increased the level of IGF-1 in the cortex. Antagonizing IGF-1 action by means of systemic injections of the IGF-1 antagonist JB1 blocked the effects of massage in rat pups. These results demonstrate that massage has an influence on brain development and in particular on visual development and suggest that its effects are mediated by specific endogenous factors such as IGF-1