Do Balance Demands Induce Shifts in Visual Proprioception in Crawling Infants?

The onset of hands-and-knees crawling during the latter half of the first year of life heralds pervasive changes in a range of psychological functions. Chief among these changes is a clear shift in visual proprioception, evident in the way infants use patterns of optic flow in the peripheral field of view to regulate their postural sway. This shift is thought to result from consistent exposure in the newly crawling infant to different patterns of optic flow in the central field of view and the periphery and the need to concurrently process information about self-movement, particularly postural sway, and the environmental layout during crawling. Researchers have hypothesized that the demands on the infant's visual system to concurrently process information about self-movement and the environment press the infant to differentiate and functionalize peripheral optic flow for the control of balance during locomotion so that the central field of view is freed to engage in steering and monitoring the surface and potentially other tasks. In the current experiment, we tested whether belly crawling, a mode of locomotion that places negligible demands on the control of balance, leads to the same changes in the functional utilization of peripheral optic flow for the control of postural sway as hands-and-knees crawling. We hypothesized that hands-and-knees crawlers (n = 15) would show significantly higher postural responsiveness to movements of the side walls and ceiling of a moving room than same-aged pre-crawlers (n = 19) and belly crawlers (n = 15) with an equivalent amount of crawling experience. Planned comparisons confirmed the hypothesis. Visual-postural coupling in the hands-and-knees crawlers was significantly higher than in the belly crawlers and pre-crawlers. These findings suggest that the balance demands associated with hands-and-knees crawling may be an important contributor to the changes in visual proprioception that have been demonstrated in several experiments to follow hands-and-knees crawling experience. However, we also consider that belly crawling may have less potent effects on visual proprioception because it is an effortful and attention-demanding mode of locomotion, thus leaving less attentional capacity available to notice changing relations between the self and the environment

Mechanisms involved in the remyelinating effect of sildenafil

Remyelination occurs in demyelinated lesions in multiple sclerosis (MS) and pharmacological treatments that enhance this process will critically impact the long term functional outcome in the disease. Sildenafil, a cyclic GMP (cGMP)-specific phosphodiesterase 5 inhibitor (PDE5-I), is an oral vasodilator drug extensively used in humans for treatment of erectile dysfunction and pulmonary arterial hypertension. PDE5 is expressed in central nervous system (CNS) neuronal and glial populations and in endothelial cells and numerous studies in rodent models of neurological disease have evidenced the neuroprotective potential of PDE5-Is. Using myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE) as a MS model, we previously showed that daily administration of sildenafil starting at peak disease rapidly ameliorates clinical symptoms while administration at symptoms onset prevents disease progression. These beneficial effects of the drug involved down-regulation of adaptive and innate immune responses, protection of axons and oligodendrocytes (OLs) and promotion of remyelination. In this work we have investigated mechanisms involved in the remyelinating effect of sildenafil. Using demyelinated organotypic cerebellar slice cultures we demonstrate that sildenafil stimulates remyelination by direct effects on CNS cells in a nitric oxide (NO)-cGMP-protein kinase G (PKG)-dependent manner. We also show that sildenafil treatment enhances OL maturation and induces expression of the promyelinating factor ciliary neurotrophic factor (CNTF) in spinal cord of EAE mice and in cerebellar slice cultures. Furthermore, we demonstrate that sildenafil promotes a M2 phenotype in bone marrow derived macrophages (BMDM) and increases myelin phagocytosis in these cells and in M2 microglia/macrophages in the spinal cord of EAE mice. Taken together these data indicate that promotion of OL maturation directly or through induction of growth factor expression, regulation of microglia/macrophage inflammatory phenotype and clearance of myelin debris may be relevant mechanisms involved in sildenafil enhancement of remyelination in demyelinated tissue and further support the contention that this well tolerated drug could be useful for ameliorating MS pathology

The Anti-Microbial Efficacy of Plant Essential Oil Combinations and Interactions with Food Ingredients

The objective of this study was to evaluate the efficacy of plant essential oils (EOs) in combination and to investigate the effect of food ingredients on their efficacy. The EOs assessed in combination included basil, lemon balm, marjoram, oregano, rosemary, sage and thyme. Combinations of EOs were initially screened against Bacillus cereus, Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa using the spot-on-agar test. The influence of varying concentrations of EO combinations on efficacy was also monitored using E. coli. These preliminary studies showed promising results for oregano in combination with basil, thyme or marjoram. The checkerboard method was then used to quantify the efficacy of oregano, marjoram or thyme in combination with the remainder of selected EOs. Fractional inhibitory concentrations (FIC) were calculated and interpreted as synergy, addition, indifference or antagonism. All the oregano combinations showed additive efficacy against B. cereus, and oregano combined with marjoram, thyme or basil also had an additive effect against E. coli and P. aeruginosa. The mixtures of marjoram or thyme also displayed additive effects in combination with basil, rosemary or sage against L. monocytogenes. The effect of food ingredients and pH on the antimicrobial efficacy of oregano and thyme was assessed by monitoring the lag phase and the maximum specific growth rate of L. monocytogenes grown in model media. The model media included potato starch (0, 1, 5 or 10%), beef extract (1.5, 3, 6 or 12%), sunflower oil (0, 1, 5 or 10%) and TSB at pH levels of 4, 5, 6 or 7. The antimicrobial efficacy of EOs was found to be a function of ingredient manipulation. Starch and oils concentrations of 5% and 10% had a negative impact on the EO efficacy. On the contrary, the EOs were more effective at high concentrations of protein, and at pH 5, by comparison with pH 6 or 7. This study suggests that combinations of EOs could minimize application concentrations and consequently reduce any adverse sensory impact in food. However, their application for microbial control might be affected by food composition, therefore, careful selection of EOs appropriate to the sensory and compositional status of the food system is required. This work shows that EOs might be more effective against food-borne pathogens and spoilage bacteria when applied to ready to use foods containing a high protein level at acidic pH, as well as lower levels of fats or carbohydrates

Antimicrobial Activity of Plant Essential Oils Using Food Model Media: Efficacy, Synergistic Potential and Interaction with Food Components

The aim of this study was to optimise the antimicrobial efficacy of plant essential oils (EOs) for control of Listeria spp. and spoilage bacteria using food model media based on lettuce, meat and milk. The EOs evaluated were lemon balm, marjoram, oregano and thyme and their minimum inhibitory concentrations (MIC) were determined against Enterobacter spp., Listeria spp., Lactobacillus spp., and Pseudomonas spp. using the agar dilution method and/or the absorbance based microplate assay. MICs were significantly lower in lettuce and beef media than in TSB. Listeria strains were more sensitive than spoilage bacteria, and oregano and thyme were the most active EOs. EO combinations were investigated using the checkerboard method and Oregano combined with thyme had additive effects against spoilage organisms. Combining lemon balm with thyme yielded additive activity against Listeria strains. The effect of simple sugars and pH on antimicrobial efficacy of oregano and thyme was assessed in a beef extract and tomato serum model media. EOs retained greater efficacy at pH 5 and 2.32% sugar, but sugar concentrations above 5% did not negatively impact EO efficacy. In addition to proven antimicrobial efficacy, careful selection and investigation of EOs appropriate to the sensory profile of foods and composition of the food system is required. This work shows that EOs might be more effective against food-borne pathogens and spoilage bacteria when applied to foods containing a high protein level at acidic pH, as well as moderate levels of simple sugars

Evolución y futuro de Hermanos S.L

El objetivo de este proyecto es analizar la viabilidad que tendría un negocio familiar dedicado a la hostelería, si una de sus partes cesa. Y si la introducción de tecnología y cambio de la estructura del organigrama mejoraría el negocio y aumentaría su beneficio.Grado en Comerci

Diagnóstico, análisis y propuesta de un modelo de servicio humanizado para la unidad de urgencias de la Clínica Universidades de La Sabana

El desarrollo del presente trabajo se realizo en la unidad de urgencias de la clínica universidad de la sabana, con el propósito de diagnosticar, analizar y proponer un modelo den servicio humanizado. Con base en la información obtenida a través de fuentes primarias y secundarias, se evidenciaron brechas entre el ser y el deber ser en los procesos de la unidad, las cuales fueron interpretadas en cinco dimensiones de servicio: tangibles, empatía, seguridad, confiabilidad y sensibilidad. De acuerdo a la información obtenida se plantean unas estrategias, un plan de mejoramiento y un modelo de servicio orientado a atender las necesidades de pacientes/usuarios, contribuyendo holísticamente al bienestar del ser humano y a la clínica en el cumplimiento de su proyección estratégica

Reproductive biology of Sphaeralcea species with ornamental interest

The genus Sphaeralcea belongs to the Malvaceae family and hasnative species from South America. Their attractive morphological characteristics with ornamental value have not yet been explored. The objective of thiswork was to know the viability of pollen, stigma receptivity, type of pollinationand combining ability of four Sphaeralcea species (S. australis, S. bonariensis, S.crispa and S. mendocina), with the aim to develop new ornamental varieties.Fructification, fertility, seed germination and survival seedlings on intraspecificand reciprocal interspecific offspring were assessed. The highest values of stigma receptivity and pollen viability were obtained at 2:00 PM for the fourspecies. S. mendocina also showed high values of pollen viability at 4:00 PM.The species proved to be self­incompatible and allogamous, with differentdegrees of reproductive compatibility. The interspecific crosses of S. mendocinaand the intraspecific of S. crispa did not produce descendants. The crossesbetween S. australis and S. bonariensis as maternal parent presented the bestcombining ability with good fruit production, seed germination and survival.This research provides useful information for the formulation and implementation of breeding strategies, to improve pollination efficiency, and to breed newSphaeralcea varieties with ornamental potential.Fil: Gutierrez, Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Monzón, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Micheletto, Sandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Marinangeli, Pablo Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina. Universidad Nacional del Sur. Departamento de Agronomía; Argentin

Ignorancia consciente en el aprendizaje de las ciencias II : factores que influyen en lo que los alumnos saben que no saben

La investigación en la didáctica de las ciencias ha examinado en detalle procesos de adquisición de conocimiento y comprensión del contenido científico. Sin embargo, se ha prestado menos atención a los papeles positivos de la incomprensión o el desconocimiento consciente. Este artículo es el segundo de dos trabajos de revisión y síntesis en los que se analiza el desconocimiento y la incomprensión conscientes de contenidos científicos. El primero se centra en los componentes y estructura de la incomprensión y en este segundo se examinan las variables que afectan al desconocimiento y a la incomprensión conscientes. En particular se revisan y sintetizan estudios sobre el efecto que tienen el conocimiento, las tareas y los criterios de coherencia en la consciencia de la incomprensión, o el desconocimiento de la ciencia, que se manifiesta generalmente a través de preguntas. Finalmente se sintetizan algunas de las implicaciones que tienen los estudios revisados para la enseñanza y el aprendizaje de las ciencias.La recerca en la didàctica de les ciències ha examinat detalladament processos d'adquisició de coneixement i comprensió del contingut científic. No obstant això, s'ha prestat menys atenció als papers positius de la incomprensió o el desconeixement conscient. Aquest article és el segon de dos treballs de revisió i síntesi en els quals s'analitza el desconeixement i la incomprensió conscients de continguts científics. El primer se centra en els components i estructura de la incomprensió i en aquest segon s'examinen les variables que afecten al desconeixement i a la incomprensió conscients. En particular es revisen i sintetitzen estudis sobre l'efecte que tenen el coneixement, les tasques i els criteris de coherència en la consciència de la incomprensió, o el desconeixement de la ciència, que es manifesta generalment a través de preguntes. Finalment se sintetitzen algunes de les implicacions que tenen els estudis revisats per a l'ensenyament i l'aprenentatge de les ciències.Much research in science education has focused on the processes of knowledge building and comprehension of scientific content. However, the positive roles of what is unknown or not understood have received much less attention. This article is the second one of two reviews that analyze the nature of what is consciously unknown or not understood about science content. The first paper focused on the components and structure of incomprehension. This second paper examines the variables influencing what is consciously not known or not understood. In particular we review and synthesize studies about the influence of knowledge, tasks, and standards of coherence on the awareness of lack of knowledge or the incomprehension of science, that is made explicit through questioning. Finally, we synthesize some implications of the revised studies for science teaching and learning

El gag y el sufrimiento humano: violencia y humor en tiempos violentos y los ocho más odiados, de Quentin Tarantino

El cine de Quentin Tarantino está identificado con el tratamiento del motivo argumental de la venganza, propio de la tradición del cine criminal y del wéstern, y con una puesta en escena de las situaciones de violencia que aprovechan a la vez los aspectos de despliegue coreográfico de su representación y las alusiones, referencias y conexiones con géneros del cine y películas específicas. El estudio de dos de sus películas, Tiempos violentos y Los ocho más odiados nos permite examinar algunos recursos expresivos empleados por Tarantino para acercar la representación de la violencia con algunos procedimientos y técnicas propias del “gag visual”, que parecerían recursos reservados para la comedia. Sin embargo, el director los acerca, los contrasta y los estiliza trabajando las posibilidades expresivas de la duración de las situaciones, de su densidad, de la sorpresa, entre otros mecanismos puestos en juego