Do negative random shocks affect trust and trustworthiness?

We report data from a variation of the trust game aimed at determining whether (and how) inequality and random shocks that affect wealth influence the levels of trust and trustworthiness. To tease apart the effect of the shock and the inequality, we compare behavior in a trust game where the inequality is initially given and one where it is the result of a random shock that reduces the second mover’s endowment. We find that first-movers send less to second-movers but only when the inequality results from a random shock. As for the amount returned, second-movers return less when they are endowed less than first-movers, regardless of whether the difference in endowments was initially given or occurred after a random shock

Trust and trustworthiness after negative random shocks

We experimentally investigate the effect of a negative endowment shock that can cause inequality in a trust game. Our goal is to assess whether different causes of inequality have different effects on trust and trustworthiness. In our trust game, we vary whether there is inequality (in favor of the second mover) or not and whether the inequality results from a random negative shock (i.e., the outcome of a die roll) or exists from the outset. Our findings suggest that inequality causes first-movers to send more of their endowment and second-movers to return more. However, we do not find support for the hypothesis that the cause of the inequality matters. Behavior after the occurrence of a random shock is not significantly different from the behavior in treatments where the inequality exists from the outset. Our results highlight the need to be cautious when interpreting the effects on trust and trustworthiness of negative random shocks in the field (such as natural disasters). Our results suggest that these effects are primarily driven by the inequality caused by the shock and not by any of the additional characteristics of the shock, like saliency or uncertainty

Dilaton thin-shell wormholes supported by a generalized Chaplygin gas

In this article, we construct spherical thin-shell wormholes with charge in dilaton gravity. The exotic matter required for the construction is provided by a generalized Chaplygin gas. We study the stability under perturbations preserving the symmetry. We find that the increase of the coupling between the dilaton and the electromagnetic fields reduces the range of the parameters for which stable configurations are possible.Comment: 14 pages, 6 figures. v3: typos correcte

A New Tool for Assessing Environmental Impacts of Altering Short-Term Flow and Water Level Regimes

The computational tool InSTHAn (indicators of short-term hydrological alteration) was developed to summarize data on subdaily stream flows or water levels into manageable, comprehensive and ecologically meaningful metrics, and to qualify and quantify their deviation from unaltered states. The pronunciation of the acronym refers to the recording interval of input data (i.e., instant). We compared InSTHAn with the tool COSH-Tool in a characterization of the subdaily flow variability of the Colorado River downstream from the Glen Canyon dam, and in an evaluation of the effects of the dam on this variability. Both tools captured the hydropeaking caused by a dam operation, but only InSTHAn quantified the alteration of key flow attributes, highlighting significant increases in the range of within-day flow variations and in their rates of change. This information is vital to evaluate the potential ecological consequences of the hydrological alteration, and whether they may be irreversible, making InSTHAn a key tool for river flow management

Ultrasonic Cutting Device for Bone Surgery Based on a Cymbal Transducer

AbstractIn this study, we introduce a new prototype ultrasonic cutting device for bone surgery based on a class V flextensional cymbal transducer, configured for use in power ultrasonics applications, which removes many of the geometrical restrictions on the cutting tip of Langevin-based transducers. The benefit of incorporating a cymbal transducer is that since the cutting blade itself does not have to be tuned, blade design can focus more closely on delivering the best interaction with bone to provide a highly accurate cut. Small variations to the geometry of the blade do not affect the final resonance frequency. Also the ultrasonic device can be miniaturised to allow the design of devices for delicate orthopaedic procedures involving minimal-access surgery. The results show how the cymbal transducer, driven by a single piezoceramic disc, can excite sufficiently high vibration displacement amplitudes at lower driving voltages. This is achieved by adapting the configuration of the cymbal to remove the problem of epoxy layer debonding, and by optimising the cymbal end-cap and geometry through finite element modelling supported with experimental vibration characterisation. Preliminary characterisations of the resulting prototype ultrasonic bone cutting device, which operates at around 25kHz, illustrate the success of this novel device design

Análisis del estado poblacional del yodo en Colombia y la necesidad de modificar los niveles de yodación universal de la sal

La deficiencia y el exceso de yodo tienen graves consecuencias para la salud humana y se han asociado con la presencia de bocio, hipotiroidismo, hipertiroidismo, cáncer de tiroides, nódulos y autoinmunidad tiroideos, así como un pobre desarrollo mental e intelectual. Los programas de yodación universal de la sal se han considerado como una de las intervenciones más rentables para la prevención de los trastornos asociados con la deficiencia de yodo; sin embargo, estos esfuerzos también han llevado a un uso excesivo de yodo en ciertas áreas geográficas, de acuerdo con el uso excesivo de sal. Como tal, la cantidad de yodo derivada del uso de la sal excede los límites que se establecen para lograr un equilibrio entre su consumo y los beneficios para la salud, lo cual conduce a efectos indeseables para la salud. En Colombia, se cumplen totalmente las recomendaciones y normas para la producción y comercialización de la sal yodada. Sin embargo, existe un notable exceso de yodo entre la población, lo cual, al menos hipotéticamente, representa un mayor riesgo para el desarrollo de trastornos funcionales y estructurales de la glándula tiroides. Esta revisión analiza los programas universales de yodación de la sal, particularmente, su impacto en la tiroides, y se centra en datos de salud pública de Colombia, en respuesta a la implementación de dicha estrategia

Can bacterial endophytes be used as a promising bio-inoculant for the mitigation of salinity stress in crop plants? : a global meta-analysis of the last decade (2011-2020)

Soil salinity is a major problem affecting crop production worldwide. Lately, there have been great research efforts in increasing the salt tolerance of plants through the inoculation of plant growth-promoting endophytic bacteria. However, their ability to promote plant growth under no-stress and salinity-stress conditions remains largely uncertain. Here, we carried out a global meta-analysis to quantify the plant growth-promoting effects (improvement of morphological attributes, photosynthetic capacity, antioxidative ability, and ion homeostasis) of endophytic bacteria in plants under no-stress and salinity-stress conditions. In addition, we elucidated the underlying mechanisms of growth promotion in salt-sensitive (SS) and salt-tolerant (ST) plants derived from the interaction with endophytic bacteria under no-stress and salinity-stress conditions. Specifically, this work encompassed 42 peer-reviewed articles, a total of 77 experiments, and 24 different bacterial genera. On average, endophytic bacterial inoculation increased morphological parameters. Moreover, the effect of endophytic bacteria on the total dry biomass, number of leaves, root length, shoot length, and germination rate was generally greater under salinity-stress conditions than no-stress conditions. On a physiological level, the relative better performance of the bacterial inoculants under the salinity-stress condition was associated with the increase in total chlorophyll and chlorophyll-b, as well as with the decrease of 1-aminocylopropane-1-carboxylate concentration. Moreover, under the salinity-stress condition, bacterial inoculation conferred a significantly higher increase in root K+ concentration and decrease in leaf Na+ concentration than under the no-stress condition. In SS plants, bacterial inoculation induced a higher increase in chlorophyll-b and superoxide dismutase activity, as well as a higher decrease in abscisic acid content, than in ST plants. Under salinity-stress, endophytic bacterial inoculation increased root K+ concentration in both SS and ST plants but decreased root Na+ concentration only in ST plants. Overall, this meta-analysis suggests that endophytic bacterial inoculation is beneficial under both no salinity-stress and salinity-stress conditions, but the magnitude of benefit is definitely higher under salinity-stress conditions and varies with the salt tolerance level of plants