Metabolomics demonstrates divergent responses of two Eucalyptus species to water stress

Past studies of water stress in Eucalyptus spp. generally highlighted the role of fewer than five “important” metabolites, whereas recent metabolomic studies on other genera have shown tens of compounds are affected. There are currently no metabolite profiling data for responses of stress-tolerant species to water stress. We used GC–MS metabolite profiling to examine the response of leaf metabolites to a long (2 month) and severe (Ψpredawn < −2 MPa) water stress in two species of the perennial tree genus Eucalyptus (the mesic Eucalyptus pauciflora and the semi-arid Eucalyptus dumosa). Polar metabolites in leaves were analysed by GC–MS and inorganic ions by capillary electrophoresis. Pressure–volume curves and metabolite measurements showed that water stress led to more negative osmotic potential and increased total osmotically active solutes in leaves of both species. Water stress affected around 30–40% of measured metabolites in E. dumosa and 10–15% in E. pauciflora. There were many metabolites that were affected in E. dumosa but not E. pauciflora, and some that had opposite responses in the two species. For example, in E. dumosa there were increases in five acyclic sugar alcohols and four low-abundance carbohydrates that were unaffected by water stress in E. pauciflora. Re-watering increased osmotic potential and decreased total osmotically active solutes in E. pauciflora, whereas in E. dumosa re-watering led to further decreases in osmotic potential and increases in total osmotically active solutes. This experiment has added several extra dimensions to previous targeted analyses of water stress responses in Eucalyptus, and highlights that even species that are closely related (e.g. congeners) may respond differently to water stress and re-waterin

Impacto de la sombra y la sequía sobre aspectos fisiológicos y de crecimiento en diversos orígenes de E. globulus subsp. globulus

Se estudiaron los efectos combinados de sombra y sequía en plantas jóvenes de Eucalyptus globulus subesp. globulus, evaluando cambios en las características fisiológicas y de crecimiento de tres procedencias (Jeeralang, Moogara y Pelverata). Las mismas crecieron bajo tres niveles de disponibilidad lumínica (pleno sol, sombra moderada, sombra severa), y dos regímenes hídricos (regadas y bajo estrés hídrico). El contenido relativo de agua de los tejidos fue menor en las plantas bajo estrés hídrico, a pleno sol y sombra moderada. La sequía redujo la conductancia estomática en Jeeralang y Pelverata, a pleno sol y sombra moderada. El potencial osmótico de la célula se redujo por el déficit hídrico en las plantas de Jeeralang y Moogara, así como en las que crecían bajo pleno sol y sombra moderada. El módulo de elasticidad de la pared celular aumentó por sequía y sombra. El ajuste en las propiedades osmóticas y elásticas determinó un incremento del potencial de presión en las plantas estresadas de pleno sol y sombra moderada. Todas las plantas sombreadas mostraron menor diámetro, pero sólo las de sombra severa tuvieron menor altura. La sequía afectó el diámetro de las plantas que crecían bajo pleno sol y a las del origen Moogara, pero redujo la altura de las plantas bajo sombra moderada y del origen Jeeralang. El área foliar específica aumentó al disminuir la intensidad de la luz. La supervivencia fue 100% en todos los tratamientos. Estos resultados muestran la capacidad de E. globulus subesp. globulus para tolerar la sequía y la sombra moderada, si bien se detectó variabilidad entre procedencias. Este comportamiento podría interpretarse como una respuesta potencial frente a condiciones de estrés múltiple de origen biótico y abiótico y permitiría planificar un manejo más eficiente en el establecimiento._____________________________The interactive effects of shade and drought were studied in young plants of Eucalyptus globulus subsp. globulus, evaluating changes in physiological and growth characteristics of three provenances (Jeeralang, Moogara and Pelverata). Plants grew under three levels of light availability (full sunlight, moderate shade and severe shade) and two water regimes (well watered and watered stress). Tissue relative water content was lower in plants under water stress, full sunlight and moderate shade. Drought reduced stomatal conductance in Jeeralang and Pelverata, under full sunlight and moderate shade. Osmotic potential decreased due to water deficit in plants of Jeeralang and Moogara, as well as in those growing under full sunlight and moderate shade. Cell wall elasticity modulus increased due to drought and shade. The adjustment in osmotic and elastic properties determined an increase in pressure potential at full turgor in stressed plants at full sunlight and moderate shade. Shaded plants showed lower diameter but only those under severe shade had lower height. Drought affected the diameter of full sunlight plants and Moogara plants, but reduced the height of moderate shaded plants and Jeeralang plants. Specific leaf area increased as the light intensity diminished. Survival was 100 % in all treatments. These results show the capacity of E. globulus subsp. globulus to tolerate drought and moderate shade, although variability among provenances was detected. This behavior could be interpreted as a potential response to biotic and abiotic multiple stress conditions allowing to plan a more efficient management during the establishment

Voiding urgency and detrusor contractility in women with overactive bladders.

To check whether the contractility of overactive bladders would be affected by voiding urgency.We urodynamically studied 100 women: 20 normal controls (group 1), 60 patients with idiopathic detrusor overactivity (DO), and 20 with neurogenic DO from intracerebral lesions. The idiopathic DO groups 2A (n = 20), 2B (n = 20), and 3 (n = 20) had moderate, severe, and no voiding urgency, respectively. The neurogenic DO group 4 had severe urgency. The delay time of urgent void at cystometry (2 minutes or more or, respectively, less than 2 minutes) defined moderate or severe urgency. Detrusor contractility was defined by the maximum bladder external voiding power (WF(max)).WF(max) was higher in the idiopathic DO patients than in the controls, had the highest values in group 2B, and did not differ significantly between groups 1-4 and 2A-3.We inferred from our data that idiopathic DO suggests a facilitation of voiding contractions and that such facilitation might be centrally amplified by severe urgency. This amplifying effect would probably be impaired in cases of neurogenic DO from intracerebral lesions

Urgency of micturition and detrusor contractility in men with prostatic obstruction and overactive bladders

Abstract Aims. In men with prostatic obstruction and detrusor overactivity (DO), to ascertain whether urgency of micturition affects bladder contractility. Materials and Methods. We urodynamically assessed five groups of 20 men each who had bladder outflow obstruction (BOO) from benign prostatic enlargement—Groups 1 (with no DO and no urgency), 2 (with DO and no urgency), 3A (with DO and moderate urgency), 3B (with DO and severe urgency), and 4 (with DO, severe urgency and chronic ischemic cerebral lesions). Urgency was graded as moderate or severe by the ability to avert an urgent void at cystometry for ≥2 or <2 min, respectively. BOO was assessed by the “Abrams–Griffiths number” (AG) and bladder contractility by the parameters PIP and WFmax. Results. AG did not differ significantly in Groups 2, 3A, and 3B, proved higher in such groups than in Group 1, and was nearly the same in Groups 1 and 4. PIP and WFmax were significantly higher in Groups 2, 3A, and 3B than in Groups 1 and 4, had the highest levels in Group 3B, and did not differ significantly in Groups 1–4 and 2–3A. Conclusions. In DO patients with prostatic obstruction there seems to be a DO-related facilitation of bladder contractility. In the same patients, severe urgency of micturition might over-amplify (i.e., enhance a DO-related facilitation of) bladder contractility, provided there are no neurogenic (chronic ischemic cerebral) lesions

What makes voters turn out: the effects of polls and beliefs

We use laboratory experiments to test for one of the foundations of the rational voter paradigm - that voters respond to probabilities of being pivotal. We exploit a setup that entails stark theoretical effects of information concerning the preference distribution (as revealed through polls) on costly participation decisions. The data reveal several insights. First, voting propensity increases systematically with subjects' predictions of their preferred alternative's advantage. Consequently, pre-election polls do not exhibit the detrimental welfare effects that extant theoretical work predicts. They lead to more participation by the expected majority and generate more landslide elections. Finally, we investigate subjects' behavior in polls and identify when Bandwagon and Underdog Effects arise