Search results for "Movement"

Glycine receptors influence radial migration in the embryonic mouse neocortex.

2011

To investigate whether glycine receptors influence radial migration in the neocortex, we analyzed the effect of glycine and the glycinergic antagonist strychnine, on the distribution of 5-bromo-2'deoxyuridine-labeled neurons in organotypic slice cultures from embryonic mice cortices. Application of glycine impeded radial migration only in the presence of the glycine-transport blockers, ALX-5407 and ALX-1393. This effect was blocked by the specific glycine receptor antagonist strychnine, whereas application of strychnine in the absence of glycine was without effect. We conclude from these observations that an activation of glycine receptors can impede radial migration, but that the glycinerg…

‘‘Distinguishing eustatic and epeirogenic controls on Lower-Middle Cambrian boundary successions in West Gondwana (Morocco and Iberia)’’, by Ed Landi…

2008

La buona scuola: la consultazione più grande d’Europa o una grande occasione perduta?

2015

L'articolo analizza la consultazione pubblica online dei cittadini (in corso dal 15 settembre al 15 novembre 2014) sulla riforma dell'istruzione nota come 'La Buona Scuola' illustrandone limiti ed effetti. L'articolo indaga inoltre sulle ragioni della protesta e sui movimenti sociali coinvolti. The article analyzes the online public consultation of citizens (underway from 15th September to 15th November 2014) on education reform known as 'The Good School Reform' illustrating its limits and effects. The article also explores the reasons for the protest against the reform and the social movements involved.

The Origins of Social Ventures

2021

This chapter addresses the social venture as a form of organization that has a role in the current society. In an economy based on markets, the intervention of multiple actors by itself—like governments, social movements, charity, and social ventures—cannot ensure the mechanisms necessary to the proper working of the system. In this way, markets present a set of failures and externalities that government action tries to solve. However, government action is limited due to a set of circumstances. Social movements and charity emerge to overcome the government’s limitations. Social entrepreneurship, as the last organization analyzed in this chapter, arises when social movements and charities fa…

Construyendo comunes para el derecho a la ciudad a través de la innovación social colectiva en la distribución y consumo: explorando un marco concept…

2022

En la actual crisis urbana, el nuevo municipalismo reclama la reconstrucción de comunes urbanos para avanzar en el derecho a la ciudad. Señala al respecto la importancia de los movimientos sociales y de la acción pública municipal para generar procesos de innovación social “desde abajo”. Sin embargo, no se ha explorado suficientemente la literatura sobre innovación social con miras a comprender la construcción de comunes urbanos. Por ello, este trabajo propone, a partir de la literatura sobre innovación social de base, un marco para explorar prácticas de generación de comunes desde la ciudadanía, así como políticas municipales que pueden articularse para apoyarlas. El marco se emplea para e…

Hand trajectories of vertical arm movements in one- G and zero- G environments

1998

The purpose of the present experiment was to study the way in which the central nervous system (CNS), represents gravitational force during vertical arm pointing movements. Movements in upward (against gravity) and downward (with gravity) directions, with two different mass loads (hand empty and with a hand-held 0.5-kg weight) were executed by eight subjects in a normal gravitational environment. Movements by two cosmonauts, in the two directions, were also tested in a state of weightlessness. Analyses focused upon finger trajectories in the saggital plane. Subjects in a normal gravitational environment showed curved paths for both directions and weight conditions. In addition, downward mov…

Adiabatic invariants drive rhythmic human motion in variable gravity.

2019

Voluntary human movements are stereotyped. When modeled in the framework of classical mechanics they are expected to minimize cost functions that may include energy, a natural candidate from a physiological point of view also. In time-changing environments, however, energy is no longer conserved---regardless of frictional energy dissipation---and it is therefore not the preferred candidate for any cost function able to describe the subsequent changes in motor strategies. Adiabatic invariants are known to be relevant observables in such systems, although they still need to be investigated in human motor control. We fill this gap and show that the theory of adiabatic invariants provides an ac…

The sensorimotor and cognitive integration of gravity.

1998

In order to demonstrate that gravity is not only a load acting locally and continuously on the body limbs, but is also used by higher levels of the nervous system as a dynamic orienting reference for the elaboration of the motor act, a review of several experiments conducted both in 1 g and 0 g are presented. During various locomotor tasks, the strategy that consists of stabilizing the head with respect to gravity illustrates one of the solutions used by the CNS to optimize the control of dynamic equilibrium. A question which remains to be solved when considering experimental results obtained in weightlessness concerns, however, the maintenance of motor schema that has evolved under normal …

Grip Force Adjustments Reflect Prediction of Dynamic Consequences in Varying Gravitoinertial Fields

2018

International audience; Humans have a remarkable ability to adjust the way they manipulate tools through a genuine regulation of grip force according to the task. However, rapid changes in the dynamical context may challenge this skill, as shown in many experimental approaches. Most experiments adopt perturbation paradigms that affect only one sensory modality. We hypothesize that very fast adaptation can occur if coherent information from multiple sensory modalities is provided to the central nervous system. Here, we test whether participants can switch between different and never experienced dynamical environments induced by centrifugation of the body. Seven participants lifted an object …

Membrane insertion and topology of the p7B movement protein of Melon Necrotic Spot Virus (MNSV)

2007

AbstractCell-to-cell movement of the Melon Necrotic Spot Virus (MNSV) is controlled by two small proteins working in trans, an RNA-binding protein (p7A) and an integral membrane protein (p7B) separated by an amber stop codon. p7B contains a single hydrophobic region. Membrane integration of this region was observed when inserted into model proteins in the presence of microsomal membranes. Furthermore, we explored the topology and targeting mechanisms of full-length p7B. Here we present evidence that p7B integrates in vitro into the ER membrane cotranslationally and with an Nt-cytoplasmic/Ct-luminal orientation. The observed topology was monitored in vivo by fusing GFP to the Ct of p7B, enab…