Cisplatin ototoxicity and hair cell regeneration in the zebrafish lateral line

Hair cell death and regeneration on the zebrafish posterior lateral line was investigated after cisplatin administration. Hair cell regeneration was first observed by 24 hours of recovery and was further analyzed after specific recovery intervals. Disruption of the notch signaling pathways by the y-secretase inhibitor DAPT resulted in an increase in hair cells at three days of recovery.

Sobre la indeterminación del Derecho y la Ley constitucional: El término "nacionalidades" como concepto jurídico indeterminado (Artículos Varios)

A partir de la idea de que un ordenamiento jurídico no debe prescindir del análisis de su lenguaje, el autor reflexiona desde la teoría juridica en torno a la vaguedad y ambigüedad de las expresiones del lenguaje, con el fin de analizar ciertos aspectos de la indeterminación de los textos jurídicos) Enumera algunas de las causas que la producen, y trata de aproximarse a aquellos presupuestos desde los cuales los operadores jurídicos se enfrentan a la problemática que se plantea cuando aplican e interpretan el Derecho o cuando lo desarrollan legislativamente. Se afronta la indeterminación en la Ley constitucional, haciendo mención especial al término ""nacionalidades"" del art. 2 de la Ley fundamental española, con objeto de tener en cuenta en este supuesto concreto algunas de las consecuencias que conlleva observar conceptos ""indeterminados"" en cualquier Ley constitucional, así como a los diversos razonamientos -direcciones doctrinales- acerca de cómo se ha producido su aplicación casuística. Trae a colación, y de una manera critica, la solución clásica que aporta al respecto la teoria de los conceptos juridicos indeterminados.

Los conceptos jurídicos indeterminados: el término mercadería en la Convención de Viena sobre contratos de compraventa internacional de mercaderías

Esta investigación versa sobre el estudio de los conceptos jurídicos indeterminados y la Convención de Viena de 1980, sobre “Contratos de Compraventa Internacional de Mercaderías”, y tiene como propósito establecer la significación explícita o implícita podría tener el término ‘mercadería, desde el análisis crítico de la teoría jurídica de los conceptos jurídicos indeterminados. En primer lugar, a través del estudio y análisis de esta teoría, fundamentada en los principales criterios de los expertos en el tema. La indeterminación es un rasgo definitorio del propio concepto de derecho, por lo que a veces puede pasar por un problema de simple interpretación, o un simple caso de argumentación jurídica, sin general interés por un estudio minucioso de sus causas, motivos y efectos. Posteriormente nos remitiremos al estudio de la Convención de Viena de 1980 desde su aspecto histórico y su innegable trascendencia frente al comercio internacional, así como a la “mercadería” y su presencia como concepto jurídico indeterminado en ella contenido. Y, terminamos el presente trabajo con el análisis del término ‘mercadería’ ya desde los diversos significados que este puede generar, a partir de su uso en el tráfico jurídico, a partir de la doctrina vertida por expertos en el tema y la jurisprudencia que emanan los órganos capaz de generar criterios vinculantes para determinar pautas o significados puntuales sobre términos vagos o lagunas en el derecho. Como último punto abarcaremos el estudio de las opciones de resolución en la teoría jurídica: la tesis de la respuesta correcta y la discrecionalidad judicial y teoría de la norma como marco.

Usos cotidianos del término sumak kawsay en el territorio kayambi

El presente estudio se centra en contrastar los discursos elaborados por intelectuales de izquierda con los significados asociados a los usos de los términos Sumak Kawsay en las comunidades del Pueblo Kayambi. Hasta ahora conocemos sobre los discursos de los intelectuales, pero se conoce poco de los significados asociados al término en las comunidades indígenas. Esto, a pesar de que los discursos intelectuales generalmente afirman que el término nació precisamente en el mundo indígena. Por ello, propusimos hacer un trabajo de campo en el territorio de Pueblo Kayambi, encontramos información en los presidentes de cabildos pertenecientes a las comunidades y organizaciones de segundo grado asentados en distintos pisos ecológicos con diferentes militancias políticas, distinto nivel de escolaridad y acceso a recursos naturales. Buscamos comparar esos usos cotidianos con los conceptos dominantes de “desarrollo”, “progreso” y “bienestar” y con la elaboración de los intelectuales respecto al “Sumak Kawsay” en el Ecuador y América Latina. En tal perspectiva, nos preguntamos, por los acercamientos y diferencias entre los usos cotidianos del Sumak Kawsay y las nociones de “desarrollo”. Preguntamos también si en el territorio Kayambi se usan las palabras “sumak” o “alli” asociadas a otras palabras distintas de “Kawsay”. Finalmente, nos preocupamos por indagar específicamente si estas expresiones y palabras se asocian con elementos de la naturaleza (tierra, agua, lluvias, plantas y otras) o con factores materiales y espirituales asociados a un tipo de vida distinto. Por esta razón, el trabajo buscó hacer un estudio de caso mediante el análisis comparativo sobre las coincidencias y diferencias conceptuales sobre el Sumak Kawsay de los intelectuales y de los líderes comunitarios del territorio Kayambi.

The role of lateral ocean physics in the upper ocean thermal balance of a coupled ocean-atmosphere GCM

The sensitivity of the upper ocean thermal balance of an ocean-atmosphere coupled GCM to lateral ocean physics is assessed. Three 40-year simulations are performed using horizontal mixing, isopycnal mixing, and isopycnal mixing plus eddy induced advection. The thermal adjustment of the coupled system is quite different between the simulations, confirming the major role of ocean mixing on the heat balance of climate. The initial adjustment phase of the upper ocean (SST) is used to diagnose the physical mechanisms involved in each parametrisation. When the lateral ocean physics is modified, significant changes of SST are seen, mainly in the southern ocean. A heat budget of the annual mixed layer (defined as the “bowl”) shows that these changes are due to a modified heat transfer between the bowl and the ocean interior. This modified heat intake of the ocean interior is directly due to the modified lateral ocean physics. In isopycnal diffusion, this heat exchange, especially marked at mid-latitudes, is both due to an increased effective surface of diffusion and to the sign of the isopycnal gradients of temperature at the base of the bowl. As this gradient is proportional to the isopycnal gradient of salinity, this confirms the strong role of salinity in the thermal balance of the coupled system. The eddy induced advection also leads to increased exchanges between the bowl and the ocean interior. This is both due to the shape of the bowl and again to the existence of a salinity structure. The lateral ocean physics is shown to be a significant contributor to the exchanges between the diabatic and the adiabatic parts of the ocean.

Lateral phase separation in grafted diblock copolymer films

Tethered films of polystyrene-block-poly(methyl methacrylate) copolymers of varying composition and molecular weight were investigated using atomic force microscopy and the observed structures compared with theoretical predictions. Although the experimental results were in qualitative agreement with the theory, there was significant quantitative variation. This was attributed to the presence of solvent in the films prior to and during annealing, a hypothesis supported by new preliminary calculations reported here. Solvent exchange experiments (where a good solvent for both polymer blocks was gradually replaced by a selective solvent), were also performed on the films. This procedure generated textured films in which the structure was defined by miscibility of the polymer blocks with the second solvent.

Stress generation in the tension wood of poplar is based on the lateral swelling power of the G-layer

The mechanism of active stress generation in tension wood is still not fully understood. To characterize the functional interdependency between the G-layer and the secondary cell wall, nanostructural characterization and mechanical tests were performed on native tension wood tissues of poplar (Populus nigra x Populus deltoids) and on tissues in which the G-layer was removed by an enzymatic treatment. In addition to the well-known axial orientation of the cellulose fibrils in the G-layer, it was shown that the microfibril angle of the S2-layer was very large (about 36 degrees). The removal of the G-layer resulted in an axial extension and a tangential contraction of the tissues. The tensile stress-strain curves of native tension wood slices showed a jagged appearance after yield that could not be seen in the enzyme-treated samples. The behaviour of the native tissue was modelled by assuming that cells deform elastically up to a critical strain at which the G-layer slips, causing a drop in stress. The results suggest that tensile stresses in poplar are generated in the living plant by a lateral swelling of the G-layer which forces the surrounding secondary cell wall to contract in the axial direction.

The remote distractor effect in saccade programming: channel interactions and lateral inhibition

We explored the dependency of the saccadic remote distractor effect (RDE) on the spatial frequency content of target and distractor Gabor patches. A robust RDE was obtained with low-medium spatial frequency distractors, regardless of the spatial frequency of the tat-get. High spatial frequency distractors interfered to a similar extent when the target was of the same spatial frequency. We developed a quantitative model based on lateral inhibition within an oculomotor decision unit. This lateral inhibition mechanism cannot account for the interaction observed between target and distractor spatial frequency, pointing to the existence of channel interactions at an earlier level. (C) 2004 Elsevier Ltd. All rights reserved.

The occipital lateral plate mesoderm - a novel source for vertebrate neck musculature

In vertebrates, body musculature originates from somites, whereas head muscles originate from the cranial mesoderm. Neck muscles are located in the transition between these regions. We show that the chick occipital lateral plate mesoderm has myogenic capacity and gives rise to large muscles located in the neck and thorax. We present molecular and genetic evidence to show that these muscles not only have a unique origin, but additionally display a distinct temporal development, forming later than any other muscle group described to date. We further report that these muscles, found in the body of the animal, develop like head musculature rather than deploying the programme used by the trunk muscles. Using mouse genetics we reveal that these muscles are formed in trunk muscle mutants but are absent in head muscle mutants. In concordance with this conclusion, their connective tissue is neural crest in origin. Finally, we provide evidence that the mechanism by which these neck muscles develop is conserved in vertebrates.

Preliminary observations on the presence of sustained tendon strain and eccentric contractions of the wrist extensors during a common manual task: implications for lateral epicondylitis

Lateral epicondylitis (LE) is hypothesized to occur as a result of repetitive, strenuous and abnormal postural activities of the elbow and wrist. There is still a lack of understanding of how wrist and forearm positions contribute to this condition during common manual tasks. In this study the wrist kinematics and the wrist extensors’ musculotendon patterns were investigated during a manual task believed to elicit LE symptoms in susceptible subjects. A 42-year-old right-handed male, with no history of LE, performed a repetitive movement involving pushing and turning a spring-loaded mechanism. Motion capture data were acquired for the upper limb and an inverse kinematic and dynamic analysis was subsequently carried out. Results illustrated the presence of eccentric contractions sustained by the extensor carpi radialis longus (ECRL), together with an almost constant level of tendon strain of both extensor carpi radialis brevis (ECRB) and extensor digitorum communis lateral (EDCL) branch. It is believed that these factors may partly contribute to the onset of LE as they are both responsible for the creation of microtears at the tendons’ origins. The methodology of this study can be used to explore muscle actions during movements that might cause or exacerbate LE.

The occipital lateral plate mesoderm is a novel source for vertebrate neck musculature

In vertebrates, body musculature originates from somites, whereas head muscles originate from the cranial mesoderm. Neck muscles are located in the transition between these regions. We show that the chick occipital lateral plate mesoderm has myogenic capacity and gives rise to large muscles located in the neck and thorax. We present molecular and genetic evidence to show that these muscles not only have a unique origin, but additionally display a distinct temporal development, forming later than any other muscle group described to date. We further report that these muscles, found in the body of the animal, develop like head musculature rather than deploying the programme used by the trunk muscles. Using mouse genetics we reveal that these muscles are formed in trunk muscle mutants but are absent in head muscle mutants. In concordance with this conclusion, their connective tissue is neural crest in origin. Finally, we provide evidence that the mechanism by which these neck muscles develop is conserved in vertebrates.

Planning autonomous vehicles in the absence of speed lanes using lateral potentials

Chaotic traffic, prevalent in many countries, is marked by a large number of vehicles driving with different speeds without following any predefined speed lanes. Such traffic rules out using any planning algorithm for these vehicles which is based upon the maintenance of speed lanes and lane changes. The absence of speed lanes may imply more bandwidth and easier overtaking in cases where vehicles vary considerably in both their size and speed. Inspired by the performance of artificial potential fields in the planning of mobile robots, we propose here lateral potentials as measures to enable vehicles to decide about their lateral positions on the road. Each vehicle is subjected to a potential from obstacles and vehicles in front, road boundaries, obstacles and vehicles to the side and higher speed vehicles to the rear. All these potentials are lateral and only govern steering the vehicle. A speed control mechanism is also used for longitudinal control of vehicle. The proposed system is shown to perform well for obstacle avoidance, vehicle following and overtaking behaviors.

Lateral boundary contributions to wave-activity invariants and nonlinear stability theorems for balanced dynamics

The slow advective-timescale dynamics of the atmosphere and oceans is referred to as balanced dynamics. An extensive body of theory for disturbances to basic flows exists for the quasi-geostrophic (QG) model of balanced dynamics, based on wave-activity invariants and nonlinear stability theorems associated with exact symmetry-based conservation laws. In attempting to extend this theory to the semi-geostrophic (SG) model of balanced dynamics, Kushner & Shepherd discovered lateral boundary contributions to the SG wave-activity invariants which are not present in the QG theory, and which affect the stability theorems. However, because of technical difficulties associated with the SG model, the analysis of Kushner & Shepherd was not fully nonlinear. This paper examines the issue of lateral boundary contributions to wave-activity invariants for balanced dynamics in the context of Salmon's nearly geostrophic model of rotating shallow-water flow. Salmon's model has certain similarities with the SG model, but also has important differences that allow the present analysis to be carried to finite amplitude. In the process, the way in which constraints produce boundary contributions to wave-activity invariants, and additional conditions in the associated stability theorems, is clarified. It is shown that Salmon's model possesses two kinds of stability theorems: an analogue of Ripa's small-amplitude stability theorem for shallow-water flow, and a finite-amplitude analogue of Kushner & Shepherd's SG stability theorem in which the ‘subsonic’ condition of Ripa's theorem is replaced by a condition that the flow be cyclonic along lateral boundaries. As with the SG theorem, this last condition has a simple physical interpretation involving the coastal Kelvin waves that exist in both models. Salmon's model has recently emerged as an important prototype for constrained Hamiltonian balanced models. The extent to which the present analysis applies to this general class of models is discussed.