Quick Analysis of Organic Amendments via Portable X-ray Fluorescence Spectrometry

The determination of heavy metals in soils and organic amendments, such as compost, manure, biofertilizer, and sludge, generally involves the digestion of samples with aqua regia, and the determination of those in the solution using various techniques. Portable X-ray fluorescence (PXRF) has many advantages in relation to traditional analytical techniques. However, PXRF determines the total elemental content and, until now, its use for the analysis of organic amendments has been limited. The objective of this work is the calibration of a PXRF instrument to determine the aqua regia-soluble elemental contents directly in solid samples of organic amendments. Our proposal will avoid the digestion step and the use of other laboratory techniques. Using a training set of samples, calibration functions were obtained that allow the determination of the aqua regia-soluble contents from the PXRF readings of total contents. The calibration functions (obtained by multiple linear regression) allowed the quantitative determination of the aqua regia-soluble contents of Fe, K, P, S, Zn, Cu, Pb, Sr, Cr, and Mn, as well as the organic matter content and a semi-quantitative assessment of Al, Ca, V, Ba, Ni, and As contents. The readings of Si, Fe, Al, Ca, K, or S were used as correction factors, indicating that the calibrations functions found are truly based on the chemical composition of the sample matrix. This study will allow a fast, cheap, and reliable field analysis of organic amendments and of other biomass-based materials.Spanish Ministry of Science, Innovation and Universities, and the European Regional Development Fund, European Union, (AEI/FEDER, UE), grant number CGL2016-78937-R

Post-embryonic organogenesis and plant regeneration from tissues: two sides of the same coin?

Plants have extraordinary developmental plasticity as they continuously form organs during post-embryonic development. In addition they may regenerate organs upon in vitro hormonal induction. Advances in the field of plant regeneration show that the first steps of de novo organogenesis through in vitro culture in hormone containing media (via formation of a proliferating mass of cells or callus) require root post-embryonic developmental programs as well as regulators of auxin and cytokinin signaling pathways. We review how hormonal regulation is delivered during lateral root initiation and callus formation. Implications in reprograming, cell fate and pluripotency acquisition are discussed. Finally, we analyze the function of cell cycle regulators and connections with epigenetic regulation. Future work dissecting plant organogenesis driven by both endogenous and exogenous cues (upon hormonal induction) may reveal new paradigms of common regulation

The social wellbeing of irrigation water. A demand-side integrated valuation in a Mediterranean agroecosystem

[EN] Irrigation water is a vital input for agricultural production. The supply of irrigation water to crops enhances land productivity and affects the agroecosystem functioning. Agroecosystems co-provide a wide range of agroecosystem services and disservices, which contribute positively and negatively, respectively, to human wellbeing. Therefore, irrigated agroecosystems produce several positive and negative outcomes in relation to society, and agricultural water management is key to the provision of adequate incentives for the enhancement of social wellbeing. In such a context, the aim of this work was to value the contribution of water to the provision of agroecosystem services and disservices, as a way to summarise the contribution of irrigation to social wellbeing. To this end, a demand-side integrated valuation of agroecosystem services and disservices was carried out for both rain-fed and irrigated agriculture in two different agroecosystems of the Region of Murcia (south-eastern Spain), a semi-arid western Mediterranean region characterised by water scarcity. In addition, the intensity of the agricultural water use was considered by distinguishing traditional and highly-intensive irrigated agroecosystems. Almond and lemon, two woody crops, were employed to develop the economic valuation in rain-fed and irrigated agroecosystems, respectively. The assessment of biophysical indicators to quantify the provision of services and disservices and their economic valuation, using market and non-market methods, were used. The results show that the contribution of water to social wellbeing is valued at 9000-12,300 euro/ha/year, being greater when the intensive use of agricultural water is promoted. The net economic value of all categories of agroecosystem services and disservices increases when irrigation water is supplied. Notwithstanding, the greatest contribution is due to the increase in provisioning services, mainly food provision in the case of the highly-intensive agroecosystem. Traditional irrigated agroecosystems make a greater contribution to regulating and cultural agroecosystem services. Hence, agricultural water management should focus on increasing the contribution of irrigated agroecosystems to human wellbeing.This work was supported by the AgriCambio project (Grant PID2020- 114576RB-I00 funded by MCIN/AEI/ 10.13039/501100011033). Jos¿e A. Zabala, Víctor Martínez-García and Jos¿e A. Albaladejo-García acknowledge the financial support from the Spanish Ministry of Education and Personal Training (FPU 16/03473; FPU19/05143; FPU 16/ 03562)Alcon, F.; Zabala, J.; Matínez-García, V.; Albaladejo, J.; López-Becerra, E.; De Miguel, MD.; Martínez-Paz, JM. (2022). The social wellbeing of irrigation water. A demand-side integrated valuation in a Mediterranean agroecosystem. Agricultural Water Management. 262. https://doi.org/10.1016/j.agwat.2021.10740026

Evolución del peso vivo durante la lactancia de corderos de raza ojalada soriana en función de determinados factores. II. Número de lactación y producción de leche.

Como complemento del trabajo presentado por Asenjo et al., 2007, se analizó la influencia del número de lactación de la madre y del nivel de pro-ducción lechera de la madre sobre la evolución del peso del cordero a lo largo del período de lactación (7 semanas). Se observó que el número de lactación, no influyó en la evolución del peso de los corderos y el nivel de producción de leche de la madre únicamente presentó significación estadís-tica (p<0,01) en la primera semana de lactación

Evolución del peso vivo durante la lactancia de corderos de raza ojalada soriana en función de determinados factores. I: Sexo, tipo de parto y peso al nacimiento del cordero.

En el presente trabajo, vamos a analizar la influencia del sexo, del tipo de parto y del peso del cordero al nacimiento, sobre la evolución del peso del cordero a lo largo del período de lactación, que en este estudio hemos considerado de 7 semanas. Para los tres factores estudiados, se encontra- ron diferencias significativas (p<0,01) en la evolución del crecimiento

Effect of size and oxidation state of size-controlled rhodium nanoparticles on the aqueous-phase hydrodechlorination of 4-chlorophenol

Unsupported size-controlled Rh nanoparticles of different size and oxidation state were tested as catalysts models in aqueous phase hydrodechlorination (303-318K, 1atm) using 4-chlorophenol (4-CP) as target compound. A chemical reduction method was employed for the synthesis of the nanoparticles using methanol and poly(N-vinyl-2-pyrrolidone) (PVP) as reducing and capping agent, respectively. The size of Rh nanoparticles was in a narrow range (1.9-4.9nm) whereas Rhn+/Rh0 ratio values were found within a wide range (0.56-3.89).High 4-CP conversion values (c.a. 100%) were achieved at low Rh concentration (2.45·10-3gL-1). Phenol, cyclohexanone, cyclohexanol and traces of cyclohexane were identified as reaction products. A wide range of activity values (1.7-29.4mmolg-1min-1) were obtained, being equivalent to the measured in a previous work with unsupported Pd nanoparticles, in spite of the fact that Rh supported catalysts have generally been reported as less active than Pd ones in liquid phase hydrodechlorination. As the size of Rh nanoparticles decreased the activity increased reaching a maximum at 2.8nm, lower size values leading to a significant decrease of activity. A remarkable dependence of activity on the Rhn+/Rh0 ratio was found, thus a higher activity corresponded to a higher relative amount of zero-valent Rh in the nanoparticles samples. Regression models were developed in order to address the significance of nanoparticles size and oxidation state for the prediction of selectivity to cyclohexanone and cyclohexanol at varying reaction times. A crossed effect of particle size and Rhn+/Rh0 ratio was identified as a significant factor influencing the selectivityWe greatly appreciate financial support from the Spanish MCYT (CTQ2009-09983 and CTQ2012-32821) and CAM (REMTAVARES S-2009/AMB-1588). J.A. Baeza thanks to the Spanish MICINN a research grant (BES-2010-030059

Interaction between genes and lifestyle factors on obesity.

Obesity originates from a failure of the body-weight control systems, which may be affected by changing environmental influences. Basically, the obesity risk depends on two important mutually-interacting factors: (1) genetic variants (single-nucleotide polymorphisms, haplotypes); (2) exposure to environmental risks (diet, physical activity etc.). Common single-nucleotide polymorphisms at candidate genes for obesity may act as effect modifiers for environmental factors. More than 127 candidate genes for obesity have been reported and there is evidence to support the role of twenty-two genes in at least five different populations. Gene-environment interactions imply that the synergy between genotype and environment deviates from either the additive or multiplicative effect (the underlying model needs to be specified to appraise the nature of the interaction). Unravelling the details of these interactions is a complex task. Emphasis should be placed on the accuracy of the assessment methods for both genotype and lifestyle factors. Appropriate study design (sample size) is crucial in avoiding false positives and ensuring that studies have enough power to detect significant interactions, the ideal design being a nested case-control study within a cohort. A growing number of studies are examining the influence of gene-environmental interactions on obesity in either epidemiological observational or intervention studies. Positive evidence has been obtained for genes involved in adiposity, lipid metabolism or energy regulation such as PPARgamma2 (Pro12Ala), beta-adrenoceptor 2 (Gln27Glu) or uncoupling proteins 1, 2 and 3. Variants on other genes relating to appetite regulation such as melanocortin and leptin receptors have also been investigated. Examples of some recently-identified interactions are discussed

High temperature internal friction in a Tie46Ale1Moe0.2Si intermetallic, comparison with creep behaviour

Advanced g-TiAl based intermetallics Mo-bearing have been developed to obtain the fine-grained microstructure required for superplastic deformation to be used during further processing. In the present work we have studied an alloy of Tie46.8Ale1Moe0.2Si (at%) with two different microstructures, as-cast material with a coarse grain size above 300 mm, and the hot extruded material exhibiting a grain size smaller than 20 mm. We have used a mechanical spectrometer especially developed for high temperature internal friction measurements to study the defect mobility processes taking place at high temperature. The internal friction spectra at different frequencies has been studied and analyzed up to 1360 K in order to characterize the relaxation processes appearing in this temperature range. A relaxation peak, with a maximum in between 900 K and 1080 K, depending on the oscillating frequency, has been attributed to Ti-atoms diffusion by the stress-induced reorientation of AleVTieAl elastic dipoles. The high temperature background in both microstructural states, as-cast and extruded, has been analyzed, measuring the apparent activation parameters, in particular the apparent energies of Ecast(IF) ¼ 4.4 ± 0.05 eV and Eext(IF) ¼ 4.75 ± 0.05 eV respectively. These results have been compared to those obtained on the same materials by creep deformation. We may conclude that the activation parameters obtained by internal friction analysis, are consistent with the ones measured by creep. Furthermore, the analysis of the high temperature background allows establish the difference on creep resistance for both microstructural states.Peer reviewe