Comparative study between Salkowski reagent and chromatographic method for auxins quantification from bacterial production.

Introduction: The Salkowski reagent method is a colorimetric technique used to determine auxin production, specifically as indole-3-acetic acid (IAA). It was developed to determine indoles rapidly; however, it does not follow Beer's law at high concentrations of IAA. Thus, there could be an overestimation of IAA with the Salkowski technique due to the detection of other indole compounds. Methods: This study aims to compare the Salkowski colorimetric method versus a chromatographic method to evidence the imprecision or overestimation obtained when auxins, such as indole-acetic acid (IAA), are determined as traits from promoting growth plant bacteria (PGPB), using ten different strains from three different isolation sources. The analysis used the same bacterial culture to compare the Salkowski colorimetric and chromatographic results. Each bacterium was cultivated in the modified TSA without or with tryptophan for 96 h. The same supernatant culture was used in both methods: Salkowski reagent and ultra-performance liquid chromatography coupled with a Mass Spectrometer (LC-MS/MS). Results: The first method indicated 5.4 to 27.4 mg L-1 without tryptophan in ten evaluated strains. When tryptophan was used as an inductor of auxin production, an increase was observed with an interval from 4.4 to 160 mg L-1. The principal auxin produced by all strains was IAA from that evaluated by the LC-MS/MS method, with significantly higher concentration with tryptophan addition than without. Strains belonging to the Kocuria genus were highlighted by high IAA production. The indole-3-propionic acid (IPA) was detected in all the bacterial cultures without tryptophan and only in K. turfanensis As05 with tryptophan, while it was not detected in other strains. In addition, indole-3-butyric acid (IBA) was detected at trace levels (13-16 µg L-1). Conclusions: The Salkowski reagent overestimates the IAA concentration with an interval of 41-1042 folds without tryptophan and 7-16330 folds with tryptophan as inductor. In future works, it will be necessary to determine IAA or other auxins using more suitable sensitive techniques and methodologies.

Microfluidic jet impacts on deep pools transition from capillary-dominated cavity closure to gas pressure-dominated closure at higher Weber numbers.

Studying liquid jet impacts on a liquid pool is crucial for various engineering and environmental applications. During jet impact, the free surface of the pool deforms and a cavity is generated. Simultaneously, the free surface of the cavity extends radially outward and forms a rim. Eventually the cavity collapses by means of gas inertia and surface tension. Our numerical investigation using an axisymmetric model in Basilisk C explores cavity collapse dynamics under different impact velocities and gas densities. We validate our model against theory and experiments across a previously unexplored parameter range. Our results show two distinct regimes in the cavity collapse mechanism. By considering forces pulling along the interface, we derive scaling arguments for the time of closure and maximum radius of the cavity, based on the Weber number. For jets with uniform constant velocity from tip to tail and We ⩽ 150 the cavity closure is capillary dominated and happens below the surface (deep seal). In contrast, for We ⩾ 180 the cavity closure happens above the surface (surface seal) and is dominated by the gas entrainment and the pressure gradient that it causes. Additionally, we monitor gas velocity and pressure throughout the impact process. This analysis reveals three critical moments of maximum gas velocity: before impact, at the instant of cavity collapse, and during droplet ejection following cavity collapse. Our results provide information for understanding pollutant transport during droplet impacts on large bodies of water, and other engineering applications, like additive manufacturing, lithography and needle-free injections.

PGPB Consortium Formulation to Increase Fermentable Sugar in Agave tequilana Weber var. Blue: A Study in the Field.

Agave tequilana Weber var. Blue is used as the primary raw material in tequila production due to its fructans (inulin) content. This study evaluates the formulation of a plant-growth-promoting bacteria (PGPB) consortium (Pseudomonas sp. and Shimwellia sp.) to increase sugars in A. tequilana under field conditions. A total of three doses were tested: low (5 L ha-1), medium (10 L ha-1), and high (15 L ha-1), with a cellular density of 1 × 108 CFU mL-1 and one control treatment (without application). Total reducing sugars (TRS), inulin, sucrose, glucose, fructose, and plant growth were measured in agave plants aged 4-5 years at 0 (T0), 3 (T3), 6 (T6), and 12 (T12) months. Yield was recorded at T12. The TRS increased by 3%, and inulin by 5.3% in the high-dose treatment compared to the control at T12. Additionally, a low content of sucrose, glucose, and fructose (approximately 1%) was detected. At T12, the weight of agave heads increased by 31.2% in the medium dose and 22.3% in the high dose compared to the control. The high dose provided a higher inulin content. The A. tequilana plants were five years old and exhibited growth comparable to the standards for 6-7-year-old plants. This study demonstrates a sustainable strategy for tequila production, optimizing the use of natural resources and enhancing industry performance through increased sugar content and yield.

Effect of Surfactants on the Splashing Dynamics of Drops Impacting Smooth Substrates.

We present the results of a systematic study elucidating the role that dynamic surface tension has on the spreading and splashing dynamics of surfactant-laden droplets during the impact on hydrophobic substrates. Using four different surfactants at various concentrations, we generated a range of solutions whose dynamic surface tension were characterized to submillisecond timescales using maximum bubble-pressure tensiometry. Impact dynamics of these solutions were observed by high-speed imaging with subsequent quantitative image processing to determine the impact parameters (droplet size and speed) and dynamic wetting properties (dynamic contact angle). Droplets were slowly formed by dripping to allow the surfactants to achieve equilibrium at the free surface prior to impact. Our results indicate that while only the fastest surfactants appreciably affect the maximum spreading diameter, the droplet morphology during the initial stages of spreading is different to water for all surfactant solutions studied. Moreover, we show that surfactant-laden droplets splash more easily than pure liquid (water). Based on the association of the splashing ratio to our tensiometry measurements, we are able to predict the effective surface tension acting during splashing. These results suggest that droplet splashing characteristics are primarily defined by the stretching of the equilibrated droplet free surface.

Dataset about Mexico's forest diversity: Site locations of tree species, wood densities, and geographic database of forest-vegetation provinces.

A dataset about three topics is provided, as a follow-up to the article "Mexico's forest diversity: common tree species and proposed forest-vegetation provinces" by Ricker et al. [1]. Firstly, 6927 site locations are provided for 22,532 trees of 1452 species. Secondly, measurements of basic wood-densities are reported for 779 tree species, obtained from 5256 trunk-core samples from Mexico's national forest inventory, and ranging from 0.05 to 0.93 g/cm3. Third, the data and maps of the forest-vegetation provinces from [1] were updated with the new cartography of Mexico's vegetation and land use (base year 2018). The maps are available now in an adjusted presentation as a shapefile-set for ArcGIS, as well as map-package and image files.

Microfluidic jet impact: Spreading, splashing, soft substrate deformation and injection.

HYPOTHESIS: Needle-free injections using microfluidic jets could be optimized by reducing splashing and controlling injection depth. However, this is impeded by an incomplete understanding on how jet characteristics influence impact outcome. We hypothesise that exploring the relation between microfluidic jet characteristics and substrate shear modulus on impact behavior will assist in predicting and giving insights on the impact outcome on skin and injection endpoints. EXPERIMENTS: To do so, a setup using microfluidic chips, at varying laser powers and stand-off distances, was used to create thermocavitation generated microfluidic jets with ranging characteristics (velocity: 7-77 m/s, diameter: 35-120 µm, Weber-number: 40-4000), which were impacted on substrates with different shear modulus. FINDINGS: Seven impact regimes were found, depending on jet Weber-number and substrate shear modulus, and we identified three thresholds: i) spreading/splashing threshold, ii) dimple formation threshold, and iii) plastic/elastic deformation threshold. The regimes show similarity to skin impact, although the opacity of skin complicated determining the threshold values. Additionally, we found that jet velocity has a higher predictive value for injection depth compared to the Weber-number, and consequently, the jet-diameter. Our findings provide fundamental knowledge on the interaction between microfluidic jets and substrates, and are relevant for optimizing needle-free injections.

Cavity dynamics after the injection of a microfluidic jet onto capillary bridges.

The ballistics of solid and liquid objects (projectiles) impacting on liquids and soft solids (targets) generally results in the creation and expansion of an air cavity inside the impacted object. The dynamics of cavity expansion and collapse depends on the projectile inertia as well as on the target properties. In this paper we study the impact of microfluidic jets generated by thermocavitation processes on a capillary bridge between two parallel planar walls. Different capillary bridge types were studied, Newtonian liquids, viscoelastic liquids and agarose gels. Thus, we compare the cavity formation and collapse between a wide range of material properties. Moreover, we model the critical impact velocity of a jet traversing a capillary bridge type. For agarose gels with a storage modulus of 176 Pa, the critical velocity is well predicted by the model used for liquids. However, the predicted critical velocity for liquids deviates for agarose gels with a storage modulus of 536 Pa and 3961 Pa. Additionally, we show different types of cavity collapse, depending on the Weber number and the capillary bridge properties. We conclude that the type of collapse determines the number and size of entrained bubbles. Furthermore, we study the effects of wettability on the adhesion forces and contact line dissipation. We also conclude that upon cavity collapse, for hydrophobic walls a Worthington jet is energetically favourable. In contrast, for hydrophilic walls, the contact line dissipation is in the same order of magnitude of the energy of the impacted jet, suppressing the Worthington jet formation. Our results provide strategies for preventing bubble entrapment and give an estimation of the cavity dynamics, of relevance for, among others, needle-free injection applications.

Droplet splashing on curved substrates.

Droplets impacting dry solid substrates often splash above a certain threshold impact velocity. We hypothesise that substrate curvature alters splashing thresholds due to a modification to the lift force acting on the lamella at the point of breakup. We have undertaken high-speed imaging experiments of millimetric droplets impacting convex and concave surfaces to establish splashing thresholds and dynamics across a wide range of substrate geometries and impact conditions. Our findings indicate that the tendency of droplets to splash is proportional to the reciprocal of the substrate's radius of curvature, independent of whether the substrate is convex or concave, with it being harder for droplets to splash on small spheres. Moreover, we consistently parameterise the axisymmetric splashing threshold across all curved substrate geometries via a modification to the well-known splashing ratio. Finally, the splashing dynamics resulting from initial asymmetry between the impacting droplet and curved substrate are also elucidated.

Impact of a microfluidic jet on a pendant droplet.

High speed microfluidic jets can be generated by a thermocavitation process: from the evaporation of the liquid inside a microfluidic channel, a rapidly expanding bubble is formed and generates a jet through a flow focusing effect. Here, we study the impact and traversing of such jets on a pendant liquid droplet. Upon impact, an expanding cavity is created, and, above a critical impact velocity, the jet traverses the entire droplet. We predict the critical traversing velocity (i) from a simple energy balance and (ii) by comparing the Young-Laplace and dynamic pressures in the cavity that is created during the impact. We contrast the model predictions against experiments, in which we vary the liquid properties of the pendant droplet and find good agreement. In addition, we assess how surfactants and viscoelastic effects influence the critical impact velocity. Our results increase the knowledge of the jet interaction with materials of well-known physical properties.

The Effect of Surface Roughness on the Contact Line and Splashing Dynamics of Impacting Droplets.

Whether a droplet splashes upon impact onto a solid is known to depend not only on the fluid properties and its speed, but also on the substrate characteristics. Past research has shown that splashing is heavily influenced by the substrate roughness. Indeed, in this manuscript, we demonstrate that splashing is ruled by the surface roughness, the splashing ratio, and the dynamic contact angle. Experiments consist of water and ethanol droplets impacting onto solid substrates with varying degrees of roughness. High speed imaging is used to extract the dynamic contact angle as a function of the spreading speed for these impacting droplets. During the spreading phase, the dynamic contact angle achieves an asymptotic maximum value, which depends on the substrate roughness and the liquid properties. We found that this maximum dynamic contact angle, together with the liquid properties, the ratio of the peak to peak roughness and the surface feature mean width, determines the splashing to no-splashing threshold. In addition, these parameters consistently differentiate the splashing behaviour of impacts onto smooth hydrophilic, hydrophobic and superhydrophobic surfaces.

Role of the Dynamic Contact Angle on Splashing.

In this Letter, we study the splashing behavior of droplets upon impact onto a variety of substrates with different wetting properties, ranging from hydrophilic to superhydrophobic surfaces. In particular, we study the effects of the dynamic contact angle on splashing. The experimental approach uses high-speed imaging and image analysis to recover the apparent contact angle as a function of the spreading speed. Our results show that neither the Capillary number nor the so-called splashing parameter are appropriate to characterize the splashing behavior under these circumstances. However, we show that the maximum dynamic advancing contact angle and the splashing ratio ß adequately characterize the splashing behavior.

Droplet impact dynamics on textiles.

The development of textiles that repel droplets following droplet impact at a high velocity is a common requirement in a number of applications, ranging from waterproof clothing to inkjet printing, yet the underpinning physical mechanisms are not entirely understood. The impact of a droplet on the surface of a textile produces two simultaneous yet separate flows, occurring above and below the surface, and which are associated with the spreading and penetration dynamics. In this paper, we study the temporal evolution of the lateral spreading diameter of a droplet impacting both hydrophobic and hydrophilic textiles. We show that the impact on textiles at short timescales involves no deformation of the droplet shape if the textile's porosity is sufficiently low. We show that the early-stage impact penetration is solely driven by inertia and no lamella is visible. We also show that for hydrophilic textiles, depending on the impact conditions, a droplet can be captured by the textile or penetrate it. We show by balancing the dynamic impact and capillary pressures that the penetration behaviour is governed by a threshold pore size, the liquid characteristics and the droplet diameter. Our conclusions highlight that the ability of a textile to repel water is controlled by the mesh size. Our experiments and analysis were carried out on coated hydrophobic and non-coated hydrophilic textiles with four corresponding mesh sizes, and are in agreement with the previous findings on hydrophobic metallic (copper) meshes.

El enfoque de sostenibilidad en los planes de salud de las comunidades autónomas: el desarrollo sostenible como oportunidad / Sustainability focus in the health plans of the autonomous communities: sustainable development as an opportunity

Objetivo: Determinar el grado de orientación de los planes de salud de las comunidades autónomas a las tres dimensiones habituales de sostenibilidad: económica, social y medioambiental; tanto en el nivel discursivo general como en las diferentes áreas de intervención. Método: Investigación cualitativa mediante análisis de contenido de una amplia muestra de documentos. La metodología específica es el análisis de sensibilidad simbólica y operativa realizado a una muestra de once planes de salud de España. Resultados: Los aspectos sociales, tales como los determinantes o los grupos más vulnerables, reciben cada vez más atención por parte del planificador sanitario, si bien hay espacio para fortalecer la atención a las cuestiones medioambientales y dotar de forma específica a las actuaciones en términos económicos. Conclusiones: el análisis evidencia el estado incipiente en el que se encuentran los planes de salud como documentos de planificación estratégica que integren aspectos económicos, sociales y ambientales con los cuales contribuir a la sostenibilidad de los diferentes sistemas sanitarios del país (AU)

Objective: To determine the degree to which the health plans of the autonomous communities focus on the usual three dimensions of sustainability: economic, social and environmental, both in the general level of discourse and in the different areas of intervention. Method: A qualitative study was conducted through content analysis of a large sample of documents. The specific methodology was analysis of symbolic and operational sensitivity in a sample of eleven health plans of the Spanish state. Results: Social aspects, such as social determinants or vulnerable groups, are receiving increasing attention from the health planner, although there is room to strengthen attention to environmental issues and to provide specific interventions in economic terms. Conclusions: The analysis demonstrates the incipient state of health plans as strategic planning documents that integrate economic, social and environmental aspects and contribute to the sustainability of the different health systems of the country (AU)

[Sustainability focus in the health plans of the autonomous communities: sustainable development as an opportunity]. / El enfoque de sostenibilidad en los planes de salud de las comunidades autónomas: el desarrollo sostenible como oportunidad.

OBJECTIVE: To determine the degree to which the health plans of the autonomous communities focus on the usual three dimensions of sustainability: economic, social and environmental, both in the general level of discourse and in the different areas of intervention. METHOD: A qualitative study was conducted through content analysis of a large sample of documents. The specific methodology was analysis of symbolic and operational sensitivity in a sample of eleven health plans of the Spanish state. RESULTS: Social aspects, such as social determinants or vulnerable groups, are receiving increasing attention from the health planner, although there is room to strengthen attention to environmental issues and to provide specific interventions in economic terms. CONCLUSIONS: The analysis demonstrates the incipient state of health plans as strategic planning documents that integrate economic, social and environmental aspects and contribute to the sustainability of the different health systems of the country.

Efficient quasi-monoenergetic ion beams from laser-driven relativistic plasmas.

Table-top laser-plasma ion accelerators have many exciting applications, many of which require ion beams with simultaneous narrow energy spread and high conversion efficiency. However, achieving these requirements has been elusive. Here we report the experimental demonstration of laser-driven ion beams with narrow energy spread and energies up to 18 MeV per nucleon and ∼5% conversion efficiency (that is 4 J out of 80-J laser). Using computer simulations we identify a self-organizing scheme that reduces the ion energy spread after the laser exits the plasma through persisting self-generated plasma electric (∼10(12) V m(-1)) and magnetic (∼10(4) T) fields. These results contribute to the development of next generation compact accelerators suitable for many applications such as isochoric heating for ion-fast ignition and producing warm dense matter for basic science.