Efecto de diferentes regimenes de riego sobre la carga frutal, tama\uf1o de fruta y rendimiento del olivo cv. Sevillana

In order to determine the effects of different regulated deficit irrigation (RDC) strategies in olives ( Olea europea L.), four irrigation treatments were applied, for three seasons, in an eight-year-old orchard of cv. 'Sevillana' olives, growing in the locality of Tierras Blanca, San Felipe, V Region, Chile (32\ub047' S; 70\ub042' W; 800 m above sea level). Treatments were: T1, irrigated at 100% of crop evapotranspiration (ETc) for the entire season; T2, 100% ETc from beginning of shoot growth until the end of fruit growth stage II and 40% ETc during stage III; T3, 100% ETc from beginning of shoot growth until the end of fruit growth stage II and 25% ETc during stage III; and T4, 60% ETc throughout the entire season. Both stem water potential and stomatal conductance were affected by RDC, especially when 40 and 25% ETc were applied. During fruit stage III, water stress did not affect the fruit-bearing load, however during this stage severe water stress affected the final fruit weight. Water stress during the whole season (60% ETc), produced a strong reduction on the fruit-bearing load of the season of high production, which seems to have its origin in the previous season. According to the results, the best strategy for RDC in olives seems to be moderate stress (application of 40% Etc) in phase III of fruit growth.Con el objetivo de determinar el efecto de diferentes estrategias de riego deficitario controlado (RDC) en olivos ( Olea europea L.), se aplicaron cuatro tratamientos de riego, en tres temporadas, a un huerto de ocho a\uf1os de edad, del cv. Sevillana, ubicado en la localidad de Tierras Blancas, San Felipe, V Regi\uf3n (32\ub047' lat. Sur, 70\ub042' long. Oeste, 800 m.s.n.m). Los tratamientos fueron: T1, regado con el equivalente al 100% de la evapotranspiraci\uf3n del cultivo (ETc) durante toda la temporada; T2, 100% de la ETc desde brotaci\uf3n hasta el t\ue9rmino de la fase II de crecimiento del fruto y 40% durante la fase III; T3, 100% de la ETc desde brotaci\uf3n hasta el t\ue9rmino de la fase II de crecimiento del fruto y 25% durante la fase III; y T4, 60% de la ETc durante toda la temporada. Tanto el potencial h\ueddrico xilem\ue1tico como la conductancia estom\ue1tica se vieron afectados por la aplicaci\uf3n de riego restringido, especialmente cuando se aplicaron 40 y 25% de la ETc. D\ue9ficit h\ueddricos durante la fase III de crecimiento de frutos no afectaron la carga frutal, sin embargo restricciones h\ueddricas severas durante esta fase tuvieron incidencia en el peso final del fruto. D\ue9ficit h\ueddricos durante toda la temporada (60% ETc), produjeron una fuerte reducci\uf3n en la carga frutal de la temporada de alta producci\uf3n, la que parece tener su origen en el a\uf1o anterior. De acuerdo a los resultados, la mejor estrategia RDC en olivo parece ser un estr\ue9s moderado (aplicaci\uf3n del 40% de la ETc) en la fase III de crecimiento del fruto

Acyl ghrelin improves cognition, synaptic plasticity deficits and neuroinflammation following amyloid beta (Aβ1-40) administration in mice

Ghrelin is a metabolic hormone that has neuroprotective actions in a number of neurological conditions, including Parkinson's disease (PD), stroke and traumatic brain injury. Acyl ghrelin treatment in vivo and in vitro also shows protective capacity in Alzheimer's disease (AD). In the present study, we used ghrelin knockout (KO) and their wild-type littermates to test whether or not endogenous ghrelin is protective in a mouse model of AD, in which human amyloid β peptide 1-40 (Aβ1-40 ) was injected into the lateral ventricles i.c.v. Recognition memory, using the novel object recognition task, was significantly impaired in ghrelin KO mice and after i.c.v. Aβ1-40 treatment. These deficits could be prevented by acyl ghrelin injections for 7 days. Spatial orientation, as assessed by the Y-maze task, was also significantly impaired in ghrelin KO mice and after i.c.v. Aβ1-40 treatment. These deficits could be prevented by acyl ghrelin injections for 7 days. Ghrelin KO mice had deficits in olfactory discrimination; however, neither i.c.v. Aβ1-40 treatment, nor acyl ghrelin injections affected olfactory discrimination. We used stereology to show that ghrelin KO and Aβ1-40 increased the total number of glial fibrillary acidic protein expressing astrocytes and ionised calcium-binding adapter expressing microglial in the rostral hippocampus. Finally, Aβ1-40 blocked long-term potentiation induced by high-frequency stimulation and this effect could be acutely blocked with co-administration of acyl ghrelin. Collectively, our studies demonstrate that ghrelin deletion affects memory performance and also that acyl ghrelin treatment may delay the onset of early events of AD. This supports the idea that acyl ghrelin treatment may be therapeutically beneficial with respect to restricting disease progression in AD

Vascular smooth muscle cells remodel collagen matrices by long-distance action and anisotropic interaction

While matrix remodeling plays a key role in vascular physiology and pathology, the underlying mechanisms have remained incompletely understood. We studied the remodeling of collagen matrices by individual vascular smooth muscle cells (SMCs), clusters and monolayers. In addition, we focused on the contribution of transglutaminase 2 (TG2), which plays an important role in the remodeling of small arteries. Single SMCs displaced fibers in collagen matrices at distances up to at least 300 μm in the course of 8–12 h. This process involved both ‘hauling up’ of matrix by the cells and local matrix compaction at a distance from the cells, up to 200 μm. This exceeded the distance over which cellular protrusions were active, implicating the involvement of secreted enzymes such as TG2. SMC isolated from TG2 KO mice still showed compaction, with changed dynamics and relaxation. The TG active site inhibitor L682777 blocked local compaction by wild type cells, strongly reducing the displacement of matrix towards the cells. At increasing cell density, cells cooperated to establish compaction. In a ring-shaped collagen matrix, this resulted in preferential displacement in the radial direction, perpendicular to the cellular long axis. This process was unaffected by inhibition of TG2 cross-linking. These results show that SMCs are capable of matrix remodeling by prolonged, gradual compaction along their short axis. This process could add to the 3D organization and remodeling of blood vessels based on the orientation and contraction of SMCs

Natural Cross Chlamydial Infection between Livestock and Free-Living Bird Species

The study of cross-species pathogen transmission is essential to understanding the epizootiology and epidemiology of infectious diseases. Avian chlamydiosis is a zoonotic disease whose effects have been mainly investigated in humans, poultry and pet birds. It has been suggested that wild bird species play an important role as reservoirs for this disease. During a comparative health status survey in common (Falco tinnunculus) and lesser (Falco naumanni) kestrel populations in Spain, acute gammapathies were detected. We investigated whether gammapathies were associated with Chlamydiaceae infections. We recorded the prevalence of different Chlamydiaceae species in nestlings of both kestrel species in three different study areas. Chlamydophila psittaci serovar I (or Chlamydophila abortus), an ovine pathogen causing late-term abortions, was isolated from all the nestlings of both kestrel species in one of the three studied areas, a location with extensive ovine livestock enzootic of this atypical bacteria and where gammapathies were recorded. Serovar and genetic cluster analysis of the kestrel isolates from this area showed serovars A and C and the genetic cluster 1 and were different than those isolated from the other two areas. The serovar I in this area was also isolated from sheep abortions, sheep faeces, sheep stable dust, nest dust of both kestrel species, carrion beetles (Silphidae) and Orthoptera. This fact was not observed in other areas. In addition, we found kestrels to be infected by Chlamydia suis and Chlamydia muridarum, the first time these have been detected in birds. Our study evidences a pathogen transmission from ruminants to birds, highlighting the importance of this potential and unexplored mechanism of infection in an ecological context. On the other hand, it is reported a pathogen transmission from livestock to wildlife, revealing new and scarcely investigated anthropogenic threats for wild and endangered species

The Toxic Effects of Cigarette Additives. Philip Morris' Project Mix Reconsidered: An Analysis of Documents Released through Litigation

Stanton Glantz and colleagues analyzed previously secret tobacco industry documents and peer-reviewed published results of Philip Morris' Project MIX about research on cigarette additives, and show that this research on the use of cigarette additives cannot be taken at face value

Topography of Extracellular Matrix Mediates Vascular Morphogenesis and Migration Speeds in Angiogenesis

The extracellular matrix plays a critical role in orchestrating the events necessary for wound healing, muscle repair, morphogenesis, new blood vessel growth, and cancer invasion. In this study, we investigate the influence of extracellular matrix topography on the coordination of multi-cellular interactions in the context of angiogenesis. To do this, we validate our spatio-temporal mathematical model of angiogenesis against empirical data, and within this framework, we vary the density of the matrix fibers to simulate different tissue environments and to explore the possibility of manipulating the extracellular matrix to achieve pro- and anti-angiogenic effects. The model predicts specific ranges of matrix fiber densities that maximize sprout extension speed, induce branching, or interrupt normal angiogenesis, which are independently confirmed by experiment. We then explore matrix fiber alignment as a key factor contributing to peak sprout velocities and in mediating cell shape and orientation. We also quantify the effects of proteolytic matrix degradation by the tip cell on sprout velocity and demonstrate that degradation promotes sprout growth at high matrix densities, but has an inhibitory effect at lower densities. Our results are discussed in the context of ECM targeted pro- and anti-angiogenic therapies that can be tested empirically

Monkeys and Humans Share a Common Computation for Face/Voice Integration

Speech production involves the movement of the mouth and other regions of the face resulting in visual motion cues. These visual cues enhance intelligibility and detection of auditory speech. As such, face-to-face speech is fundamentally a multisensory phenomenon. If speech is fundamentally multisensory, it should be reflected in the evolution of vocal communication: similar behavioral effects should be observed in other primates. Old World monkeys share with humans vocal production biomechanics and communicate face-to-face with vocalizations. It is unknown, however, if they, too, combine faces and voices to enhance their perception of vocalizations. We show that they do: monkeys combine faces and voices in noisy environments to enhance their detection of vocalizations. Their behavior parallels that of humans performing an identical task. We explored what common computational mechanism(s) could explain the pattern of results we observed across species. Standard explanations or models such as the principle of inverse effectiveness and a “race” model failed to account for their behavior patterns. Conversely, a “superposition model”, positing the linear summation of activity patterns in response to visual and auditory components of vocalizations, served as a straightforward but powerful explanatory mechanism for the observed behaviors in both species. As such, it represents a putative homologous mechanism for integrating faces and voices across primates