Uso del análisis isotópico del carbono y del nitrógeno en la trazabilidad de productos derivados del cerdo ibérico

La producción tradicional de cerdo Ibérico es un claro ejemplo de sistema extensivo de producción animal sostenible, respetuosa con el entorno, en la línea marcada por las tendencias actuales de la Política Agraria de los países de la Unión Europea. La pureza racial y la alimentación basada en la bellota, en la fase fi nal de cebo durante la montanera en la dehesa mediterránea, son los dos principales factores que afectan a la calidad de los productos derivados de la industria del cerdo Ibérico. El alto valor económico que alcanzan los productos curados cuando proceden de animales producidos en las citadas condiciones hace necesaria la regulación e identifi cación de los productos que cumplen estos requisitos. Las relaciones isotópicas 15N/14N y 13C/12C determinadas en tejidos de cerdo Ibérico al sacrifi cio tienen cierto valor potencial como método de identificación y control del tipo de alimentación al que ha estado sometido el animal durante la fase final de cebo previa al sacrificio, es decir, constituyen una herramienta prometedora en la trazabilidad de materiales para diferenciar animales de bellota, recebo y cebo a pienso. Se analizan las variaciones en estas relaciones isotópicas debidas a los tres tipos de alimentación mencionados, en un trabajo de carácter preliminar realizado en colaboración con el Grupo de Biogeoquímica de Isótopos estables de la Estación Experimental del Zaidín

Kramers polarization in strongly correlated carbon nanotube quantum dots

Ferromagnetic contacts put in proximity with carbon nanotubes induce spin and orbital polarizations. These polarizations affect dramatically the Kondo correlations occurring in quantum dots formed in a carbon nanotube, inducing effective fields in both spin and orbital sectors. As a consequence, the carbon nanotube quantum dot spectral density shows a four-fold split SU(4) Kondo resonance. Furthermore, the presence of spin-orbit interactions leads to the occurrence of an additional polarization among time-reversal electronic states (polarization in the time-reversal symmetry or Kramers sector). Here, we estimate the magnitude for the Kramer polarization in realistic carbon nanotube samples and find that its contribution is comparable to the spin and orbital polarizations. The Kramers polarization generates a new type of effective field that affects only the time-reversal electronic states. We report new splittings of the Kondo resonance in the dot spectral density which can be understood only if Kramers polarization is taken into account. Importantly, we predict that the existence of Kramers polarization can be experimentally detected by performing nonlinear differential conductance measurements. We also find that, due to the high symmetry required to build SU(4) Kondo correlations, its restoration by applying an external field is not possible in contrast to the compensated SU(2) Kondo state observed in conventional quantum dots.Comment: 8 pages, 4figure

Sustainable one-pot immobilization of enzymes in/on metal-organic framework materials

peer-reviewedThe industrial use of enzymes generally necessitates their immobilization onto solid supports. The well-known high affinity of enzymes for metal-organic framework (MOF) materials, together with the great versatility of MOFs in terms of structure, composition, functionalization and synthetic approaches, has led the scientific community to develop very different strategies for the immobilization of enzymes in/on MOFs. This review focuses on one of these strategies, namely, the one-pot enzyme immobilization within sustainable MOFs, which is particularly enticing as the resultant biocomposite Enzyme@MOFs have the potential to be: (i) prepared in situ, that is, in just one step; (ii) may be synthesized under sustainable conditions: with water as the sole solvent at room temperature with moderate pHs, etc.; (iii) are able to retain high enzyme loading; (iv) have negligible protein leaching; and (v) give enzymatic activities approaching that given by the corresponding free enzymes. Moreover, this methodology seems to be near-universal, as success has been achieved with different MOFs, with different enzymes and for different applications. So far, the metal ions forming the MOF materials have been chosen according to their low price, low toxicity and, of course, their possibility for generating MOFs at room temperature in water, in order to close the cycle of economic, environmental and energy sustainability in the synthesis, application and disposal life cycle

Component-Resolved in Vitro Diagnosis in Peach-Allergic Patients

BACKGROUND: The in vitro diagnosis of pollen-related food allergy presents low specifi city and reproducibility with many conventional extracts. This can be improved using natural purifi ed allergens, recombinant purifi ed allergens, or both. OBJECTIVE: We compared specifi c immunoglobulin (Ig) E determination (sIgE), the basophil activation test (BAT), the histamine release test (HRT), and the cellular allergen stimulation test (CAST) using natural and recombinant allergens in the diagnosis of peach allergy. METHODS: Thirty-two peach allergic patients were studied. Skin prick tests were performed with commercial peach and extract with Mal d 1, nPru p 3, and profi lin (nPho d 2). sIgE, BAT, CAST, and HRT were determined using rPru p 3, rMal d 3, rBet v 1, rMal d 1, and rMal d 4. RESULTS: Agreement between the techniques was good with all the allergens, except HRT with rMal d 1 and rMal d 4. With rPru p 3, sIgE, CAST, BAT, and HRT showed sensitivity values of 88%, 81%, 72%, and 69% and specifi city values of 100%, 93%, 97%, and 83%, respectively. In patients with systemic symptoms or contact urticaria, the values were 100%, 85%, 81%, and 81%. In patients with oral allergy syndrome, sensitivity to profi lins or homologues of Bet v 1 was detected in 100% of the cases by all the techniques, except by HRT with rMal d 1, which detected 66% of the cases. CONCLUSIONS: The use of single allergens in the in vitro diagnosis of peach allergy by specifi c IgE determination, BAT, and CAST offers high specifi city and sensitivity, with better results than the HRT

Desvío de recursos públicos, es viable su recuperación a través del procedimiento administrativo y el de ejecución

El objetivo de este trabajo es proponer procedimientos administrativos que permitan recuperar recursos públicos desviados y sancionar el incumplimiento a los acuerdos, convenios o contratos celebrados principalmente con particulares, organizaciones de la sociedad civil y grupos sociales, para ejecutar programas contemplados en el Presupuesto de Egresos de la Federación. Se revisa el caso de una resolución administrativa que no fue recurrida y que actualmente es firme, en la cual se siguió el procedimiento administrativo por parte de la autoridad administrativa, se determinó el recurso que fue recibido indebidamente y se estableció su recuperación a través del procedimiento administrativo de ejecución. Lo que se pretende demostrar en este trabajo es que si se aplica un método de interpretación analítico e inclusivo de cierta normativa vigente en el orden jurídico mexicano, es posible determinar que al utilizar los procedimientos administrativos antes mencionados, se pueden recuperar rápida y eficazmente los recursos públicos que se desvían por los ejecutores del gasto público y que causan un daño al erario federal

Hydropower Technology for Sustainable Energy Generation in Wastewater Systems: Learning from the Experience

[EN] Hydropower is a well-known technology, applied worldwide for electricity generation from renewable sources. Within the current framework, some studies have started to consider its application to existing urban water systems, to harness an excess of energy that otherwise would be wasted. This research sought to determine a methodology to assess the potential of hydropower application to wastewater treatment plants (WWTPs), regarding different aspects of sustainability. Firstly, previously developed methodologies for potential assessment in this sector at a country level were analyzed. Secondly, data from existing real case studies were gathered from publicly available documents and a theoretical analysis of their actual performance was conducted to validate assumptions made in the previous methodologies. As a result, the proposed new approach suggests adapting methodologies for potential assessment at a lower level, considering possible driving factors, other than economic feasibility. To define the study area, the management model scope should be considered. The power to determine the cut-off point for a WWTP to be considered as a potential site, is proposed to be lowered according to technical feasibility. Additionally, bearing in mind the sustainability concept, social or environmental factors should also be introduced in the methodology, tailored to the region being assessed. This novel perspective could provide a closer approach to the most likely decision-making level for these kinds of strategies in the wastewater industry.Grant PID2020-114781RA-I00 funded by MCIN/AEI/10.13039/501100011033.Llácer-Iglesias, RM.; López Jiménez, PA.; Pérez-Sánchez, M. (2021). Hydropower Technology for Sustainable Energy Generation in Wastewater Systems: Learning from the Experience. Water. 13(22):1-31. https://doi.org/10.3390/w13223259S131132

Exploring options for energy recovery from wastewater: Evaluation of hydropower potential in a sustainability framework

[EN] Current energy demand for wastewater treatment is very high and expected to increase in the next decade. As climate change poses a challenge too, renewable energy options for this industry are needed. Studies for hy-dropower assessment addressed to governance stakeholders have shown that some mechanical energy might be recovered from wastewater. However, none of them applied a sustainability approach. Neither the decision -making level was considered. The objective of this work is to present a methodology, developed and applied to a case study, with a novel approach, including all these considerations. After analyzing the context in the region of study, the proposed methodology includes all three dimensions of sustainability: economic, environ-mental, and social. Firstly, the methodology was applied to a group of 186 plants, selected according to their management model. Based on technical feasibility, 34 potential sites were identified. Secondly, to obtain the sustainability perspective, a survey of suitable criteria was conducted. Then, a multi-criteria method, aligned with existing governance guidelines, was proposed and applied. The results show that, in a sustainability framework, hydropower might be an interesting option to consider for the decarbonization of wastewater sys-tems. Based on this study, stakeholders could directly design decision-making methodologies adapted to their context.The authors would like to thank Laboratorios Tecnologicos de Levante for their contribution to the questionnaires used in this study. The authors would like to acknowledge grant PID2020-114781RA-I00 funded by MCIN/AEI/10.13039/501100011033. Funding for open access charge: CRUE-Universitat Politecnica de Valencia.Llácer-Iglesias, RM.; López Jiménez, PA.; Pérez-Sánchez, M. (2023). Exploring options for energy recovery from wastewater: Evaluation of hydropower potential in a sustainability framework. Sustainable Cities and Society (Online). 95:1-18. https://doi.org/10.1016/j.scs.2023.1045761189

A Novel High-Performance Length Matching Element for High-Speed Interconnect Differential Channels

Length matching elements (LME) are used for intra-pair length matching and inter-pair skew reduction to get high data rates in high-speed differential channels. Although these structures are widely used in printed circuit boards (PCB), the effectiveness of the structure depends on its geometry and dimensions, allowing different design alternatives. In this work, a novel LME for PCB designs is proposed. It is formed by three sub-structures, such that the insertion and impedance profile can be parametrically controlled by the geometry of the proposed LME without affecting the length matching. Mixed-mode parameters, extracted from simulation data, shows that the proposed LME presents lower insertion loss and less electromagnetic interference (EMI), than trapezoidal LME. In addition, time domain reflected analysis (TDR) shows better impedance profile for the proposed LME than for the trapezoidal shape. Both frequency- and time-domain results indicate that the proposed LME can be a good alternative for length matching compensation in high-speed channels

EM Parametric Study of Length Matching Elements Exploiting an ANSYS HFSS Matlab-Python Driver

This work presents a Python-based driver for ANSYS HFSS for length matching elements (LME) implemented in Matlab. The driver allows full-wave EM parametric simulation of length matching elements, whose S-parameters are inserted in other circuit simulators, such as ADS, for a complete interconnect validation. Three different LME (i.e., trapezoidal, triangular, and rectangular) are analyzed using the driver in a common high-speed routing scenario. The driver proposed in this work allows verifying that the three LME considered have a similar performance up to 5 GHz, indicating that these LME can be used as mismatch (phase skew) compensation structures in some interfaces within this frequency band, such as USB 3.0, PCIe Gen3 or 1 GBASE Ethernet. On the other hand, the trapezoidal LME shows the best performance for frequencies higher than 5 GHz, with a low impact in the electromagnetic interference (EMI), making it the most recommended for high-speed interfaces with operating frequencies higher than 5 GHz