Modelos de pago en el sector de la prensa: una estrategia defensiva

Estudio publicado en El Libro Blanco de la prensa diaria 2013, publicado por la Asociación de Editores de Diarios Españoles (2013). Versa sobre la naturaleza y características de la estrategia de pago desarrollada por la prensa digital española e los últimos años

ONCE MORE ON THE BIOMECHANICAL PRINCIPLE OF THE INITIAL FORCE. THIS TIME IN CEREBRAL PALSY

The main purpose of the study was to evaluate the patterns of the developed ground reaction forces in the two – legged countermovement jumping, performed by persons affected by tetraparesis with ataxia, tetraparesis with athetosis, tetraparesis with spasticity, diplegia with spasticity, right and left hemiplegia and, finally, right and left hemiparesis. After twenty subjects jumped on the surface of a force plate analysis of the ground reaction force – time trend took place. The obtained results confirm the accomplishment of the biomechanical principle of the initial force as in the case of persons not affected by neurological disorders. Finally the calculated ratio between the breaking impulse and the acceleration impulse is very near to optimum values (.3 to .4)

A yeast three-hybrid system that reconstitutes mammalian hypoxia inducible factor regulatory machinery

Background: Several human pathologies, including neoplasia and ischemic cardiovascular diseases, course with an unbalance between oxygen supply and demand ( hypoxia). Cells within hypoxic regions respond with the induction of a specific genetic program, under the control of the Hypoxia Inducible Factor (HIF), that mediates their adaptation to the lack of oxygen. The activity of HIF is mainly regulated by the EGL-nine homolog (EGLN) enzymes that hydroxylate the alpha subunit of this transcription factor in an oxygen-dependent reaction. Hydroxylated HIF is then recognized and ubiquitinilated by the product of the tumor suppressor gene, pVHL, leading to its proteosomal degradation. Under hypoxia, the hydroxylation of HIF by the EGLNs is compromised due to the lack of oxygen, which is a reaction cosubstrate. Thus, HIF escapes degradation and drives the transcription of its target genes. Since the progression of the aforementioned pathologies might be influenced by activation of HIF-target genes, development of small molecules with the ability to interfere with the HIF-regulatory machinery is of great interest.Results: Herein we describe a yeast three-hybrid system that reconstitutes mammalian HIF regulation by the EGLNs and VHL. In this system, yeast growth, under specific nutrient restrictions, is driven by the interaction between the beta domain of VHL and a hydroxyproline-containing HIF alpha peptide. In turn, this interaction is strictly dependent on EGLN activity that hydroxylates the HIFa peptide. Importantly, this system accurately preserves the specificity of the hydroxylation reaction toward specific substrates. We propose that this system, in combination with a matched control, can be used as a simple and inexpensive assay to identify molecules that specifically modulate EGLN activity. As a proof of principle we show that two known EGLN inhibitors, dimethyloxaloylglycine (DMOG) and 6-chlor-3-hydroxychinolin-2-carbonic acid-N-carboxymethylamide (S956711), have a profound and specific effect on the yeast HIF/EGLN/VHL system.Conclusion: The system described in this work accurately reconstitutes HIF regulation while preserving EGLN substrate specificity. Thus, it is a valuable tool to study HIF regulation, and particularly EGLN biochemistry, in a cellular context. In addition, we demonstrate that this system can be used to identify specific inhibitors of the EGLN enzymes

Historical Synthesis-Analysis of Changes in Grain Nitrogen Dynamics in Sorghum

Citation: Ciampitti IA and Prasad PVV (2016) Historical Synthesis-Analysis of Changes in Grain Nitrogen Dynamics in Sorghum. Front. Plant Sci. 7:275. doi: 10.3389/fpls.2016.00275Unraveling the complexity underpinning nitrogen (N) use efficiency (NUE) can be physiologically approached via examining grain N sources and N internal efficiency (NIE) (yield to plant N content ratio). The main objective of this original research paper is to document and understand sorghum NUE and physiological mechanisms related to grain N dynamics. The study of different grain N sources, herein defined as the reproductive-stage shoot N remobilization (Remobilized N), reproductive-stage whole-plant N content (Reproductive N), and vegetative-stage whole-plant N content (Vegetative N), was pursued with the goal of synthesizing scientific literature for sorghum [Sorghum bicolor (L.) Moench] crop. A detailed literature review was performed and summarized on sorghum NUE (13 studies; >250 means) with three Eras, defined by the year of the study, named as Old Era (1965–1980); Transient Era (1981–2000); and New Era (2001–2014). The most remarkable outcomes from this synthesis were: (1) overall historical (1965–2014) cumulative yield gain was >0.5 Mg ha-1 (yields >7 Mg ha-1); (2) NIE did not change across the same time period; (3) grain N concentration (grain %N) accounted for a large proportion (63%) of the variation in NIE; (4) NIE increased as grain %N diminished, regardless of the Eras; (5) Remobilized N was strongly (>R2 0.6) and positively associated with Vegetative N, presenting a unique slope across Eras; and (6) a trade-off was documented for the Remobilized N and Reproductive N (with large variation, <R2) relationship, suggesting complex regulation processes governing N forces. Improvements in NUE are subjected to the interplay between N supply (N from non-reproductive organs) and grain N demand, sink- (driven by grain number) and source-modulated (via restriction of grain N demand)

STABILOMETRY APPLIED ON THE ANALYSIS OF INDIVIDUAL TECHNIQUE IN THE AIR - RIFLE SHOOTING

The main problem of sport technique in shooting sports is to maintain the body segments as stable as possible. Experimental data proved that shooters adopt a mechanically unstable posture as consequence of the interactions among body segments. Stabilometric analysis, by means of force plates, allows the evaluation of postural stability, measuring displacements of the center of pressure (COP). In this study the postural stability of a high level air - rifle shooter and its relationship with performance has been evaluated. The results confirmed that it is possible to obtain relevant information with respect to shooter's technique, given that, the shooter displayed a trend to achieve better shots trying to intercept the center of the target with moving the whole body – rifle system forwards (

STABILOMETRY APPLIED ON THE ANALYSIS OF INDIVIDUAL TECHNIQUE IN THE AIR - RIFLE SHOOTING

The main problem of sport technique in shooting sports is to maintain the body segments as stable as possible. Experimental data proved that shooters adopt a mechanically unstable posture as consequence of the interactions among body segments. Stabilometric analysis, by means of force plates, allows the evaluation of postural stability, measuring displacements of the center of pressure (COP). In this study the postural stability of a high level air - rifle shooter and its relationship with performance has been evaluated. The results confirmed that it is possible to obtain relevant information with respect to shooter's technique, given that, the shooter displayed a trend to achieve better shots trying to intercept the center of the target with moving the whole body – rifle system forwards (