Socio-spatial research on logistics and its impact on urban environment: A review

This review article attempts to respond to the following research questions: How has evolved socio-spatial analysis on logistics, which are the most studied types of this economic activity, and the major impacts of logistics on urban space. This article draws on a systemized bibliometric analysis to identify the main tendencies in logistics' spatial study. It identifies four clusters of literature that put interest on different subtopics and approaches. The review reveals the current hegemony of applied research that focuses on sustainability, streamlining, and technology, mainly from the USA and China, despite research on globalization and industry. In fact, concerning the urban space, the most vivid academic discussion revolves around the location of warehousing and transport activity within cities. Finally, the article highlights the lack of critical perspectives on logistics and socio-spatial conflicts generated by logistics extension inmainstream academic literature. The analysis concludes that socio-spatial disputes related to logistics remain understudied and, consequently, further research should be conducted on this field. © 2021 WITPress. All rights reserved.This work was supported by the European Commision-Erasmus+ Programme under Grant 611583-EPP-1-2019-1-ES-EPPJMO-MODULE; and the Instituto Universitario para el Desarrollo social y Sostenible (INDESS) of the University of Cádiz. The authors would like to thank Iban Diaz-Parra for his valuable suggestions on previous draft of the manuscript and to the help of Alex Aguirre and Álvaro García Rosa with different stages of the research process

Diseño y desarrollo de un gadget de e-health basado en bluetooth low energy y compatible con dispositivos móviles inteligentes Android

Este trabajo tiene como objetivo diseñar un sistema que permita monitorizar el ritmo cardíaco, utilizando un circuito diseñado especialmente para acondicionar dicha señal, y apoyándose en un SoC (System on Chip) para hacer la lectura de la señal, la recopilación de datos y el envío de los datos al Smartphone, y una aplicación de Android para monitorizarlos. Por tanto, se plantean los siguientes objetivos para realizar el sistema propuesto: • Estudiar y elegir entre los diferentes métodos utilizados para la medición del pulso cardíaco, seleccionar el sensor y componentes necesarios para la utilización del método. • Seleccionar una placa de desarrollo para implementar el protocolo Bluetooth Low Energy a través de un sistema de tipo SoC. • Diseñar la electrónica de acondicionamiento necesaria para incorporar el sensor al sistema. • Estudiar el diseño de aplicaciones con protocolo BLE en sistemas SoC. • Estudiar la arquitectura de Android para implementar una aplicación sobre un dispositivo móvil inteligente. • Realizar las pruebas de funcionamiento necesarias para validar la arquitectura propuesta.Escuela Técnica Superior de Ingeniería IndustrialUniversidad Politécnica de Cartagen

Estudio del carbonato de litio como ayuda de sinterización para óxido de estaño mediante diseños de experimentos: variables principales y cambios microestructurales

Tin oxide is one of the most extensively studied semiconductor materials due to its broad field of applications. On the one hand, its high conductivity and its corrosion resistance are the most remarkable properties. Therefore, one of the most developed uses in the recent decades has been as ceramic electrode for electrooxidation process. On the other hand, its poor sinterability hinders a broader use. As a result, the use of advanced techniques or sin- tering aids for obtaining low-porosity specimens is necessary. So far, many additives have been studied, CaCO3, Co3O4, Nb2O5 or MnO2, among others. In the present work, the sinter- ing behaviour of SnO2-based powder, containing Li2CO3 as a sintering aid, which generates a liquid phase, has been analysed, since it is one of the additives that has been studied to a lesser extent. The effect of the amount of sintering aid just like the thermal treatment parameters (maximum temperature, heating rate and soaking time) on volumetric contrac- tion’s evolution has been studied through a factorial experiment designs 2n. The results show that an amount of lithium carbonate greater than 1 mol.% is unfavourable to densification. With regards to the thermal cycle’s parameters, it is advisable to have thermal treatments at high temperatures (1300 ◦C) with moderate soaking times (1 h), as maximum temperatures have the biggest influence on the densification followed by soaking time while the heating rate has a lesser influence. Under these conditions, a microstructure of closed and rounded pores is obtained, in which a residual phase is enclosed, but the small proportion of which prevents its characterisation.El óxido de esta ̃no es uno de los materiales más estudiados, dado su extenso campo de aplicación. De entre sus propiedades, cabe destacar su alta conductividad eléctrica y su resistencia a la corrosión, de ahí que entre sus aplicaciones se encuentre la de electrodo cerámico. Sin embargo, su baja capacidad de densificación dificulta su uso. Como con- secuencia, se requieren técnicas avanzadas o aditivos de sinterización que faciliten la obtención de piezas con baja porosidad. Hasta el momento han sido muchos los aditivos estudiados, CaCO3, Co3O4, Nb2O5 o MnO2, entre otros. En este trabajo se estudia el proceso de sinterización de piezas de SnO2 a las que se ha incorporado Li2CO3 como aditivo de sinterización, el cual genera una fase líquida, por ser uno de los aditivos en cuyo estudio se ha profundizado en menor medida. A través de dise ̃nos factoriales de experimentos 2n, se han determinado los efectos de los diferentes parámetros del ciclo de cocción (temper- atura máxima, velocidad de calentamiento y tiempo de permanencia), así como la cantidad de aditivo de sinterización, sobre la evolución de la contracción volumétrica. Los resulta- dos muestran que la incorporación del carbonato de litio, en porcentajes superiores al 1% molar, no es favorable para la densificación. Respecto a los parámetros de cocción, resul- tan recomendables tratamientos térmicos a elevada temperatura (1.300 ◦C) con tiempos de permanencia moderados (1 hora), mientras que la velocidad de calentamiento ejerce una menor influencia. En estas condiciones se obtiene una microestructura de poros cerrados y redondeados, en la que queda encerrada una fase residual cuya reducida proporción impide su caracterización

Application of Dispersive Liquid–Liquid Aerosol Phase Extraction to the Analysis of Total and Individual Phenolic Compounds in Fried Extra Virgin Olive Oils

Seventeen extra virgin olive oil samples from Valencian Community (Spain) were submitted to a domestic-frying process (180 °C) during different degradation times (5, 10, 30, 60, 120 min). A dispersive liquid–liquid aerosol phase extraction by using a methanol/water (50:50) extracting solution was used to isolate the polyphenol fraction. Total phenolic content (TPC) was determined, whereas the determination of seven individual target polyphenolic compounds (hydroxytyrosol, tyrosol, oleuropein, vanillic acid, p-coumaric acid, ferulic acid, and vanillin) was carried out by using ultrahigh-performance liquid chromatography coupled to a tandem mass spectrometer. Statistically significant differences in the TPC values were found for Blanqueta and Manzanilla samples from different harvesting years. The domestic-frying process impacted the TPC and the individual phenolic compounds content. Thermal treatment for 2 h gave rise to a 94% decrease in the TPC. A first-order kinetic model was suitable to accurately describe the degradation of the individual phenolic compounds.The authors wish to thank the Spanish Ministry of Science, Innovation, and Universities for the financial support (project ref. PID2021-127566NB-I00)

Dorsal and ventral stimuli in cell–material interactions: effect on cell morphology

Cells behave differently between bidimensional (2D) and tridimensional (3D) environments. While most of the in vitro cultures are 2D, most of the in vivo extracellular matrices are 3D, which encourages the development of more relevant culture conditions, seeking to provide more physiological models for biomedicine (e.g., cancer, drug discovery and tissue engineering) and further insights into any dimension-dependent biological mechanism. In this study, cells were cultured between two protein coated surfaces (sandwich-like culture). Cells used both dorsal and ventral receptors to adhere and spread, undergoing morphological changes with respect to the 2D control. Combinations of fibronectin and bovine serum albumin on the dorsal and ventral sides led to different cell morphologies, which were quantified from bright field images by calculating the spreading area and circularity. Although the mechanism underlying these differences remains to be clarified, excitation of dorsal receptors by anchorage to extracellular proteins plays a key role on cell behavior. This approach—sandwich-like culture—becomes therefore a versatile method to study cell adhesion in well-defined conditions in a quasi 3D environment

Role of Surface Chemistry in Protein Remodeling at the Cell-Material Interface

Background: The cell-material interaction is a complex bi-directional and dynamic process that mimics to a certain extent the natural interactions of cells with the extracellular matrix. Cells tend to adhere and rearrange adsorbed extracellular matrix (ECM) proteins on the material surface in a fibril-like pattern. Afterwards, the ECM undergoes proteolytic degradation, which is a mechanism for the removal of the excess ECM usually approximated with remodeling. ECM remodeling is a dynamic process that consists of two opposite events: assembly and degradation. Methodology/Principal Findings: This work investigates matrix protein dynamics on mixed self-assembled monolayers (SAMs) of –OH and –CH3 terminated alkanethiols. SAMs assembled on gold are highly ordered organic surfaces able to provide different chemical functionalities and well-controlled surface properties. Fibronectin (FN) was adsorbed on the different surfaces and quantified in terms of the adsorbed surface density, distribution and conformation. Initial cell adhesion and signaling on FN-coated SAMs were characterized via the formation of focal adhesions, integrin expression and phosphorylation of FAKs. Afterwards, the reorganization and secretion of FN was assessed. Finally, matrix degradation was followed via the expression of matrix metalloproteinases MMP2 and MMP9 and correlated with Runx2 levels. We show that matrix degradation at the cell material interface depends on surface chemistry in MMP-dependent way. Conclusions/Significance: This work provides a broad overview of matrix remodeling at the cell-material interface, establishing correlations between surface chemistry, FN adsorption, cell adhesion and signaling, matrix reorganization and degradation. The reported findings improve our understanding of the role of surface chemistry as a key parameter in the design of new biomaterials. It demonstrates the ability of surface chemistry to direct proteolytic routes at the cell-material interface, which gains a distinct bioengineering interest as a new tool to trigger matrix degradation in different biomedical applications

DWDM Fiber-Wireless Access System with Centralized Optical Frequency Comb-based RF Carrier Generation

Publisher copyright and source must be acknowledged with citation. Must link to publisher version with DOI.[EN] In this paper, we report on a gigabit capacity fiber-wireless system that enables smooth integration between high-speed wireless networks and dense wavelength-division-multiplexing (DWDM) access networks. By employing a centralized optical frequency comb, both the wireline and the wireless services for each DWDM user can be simultaneously supported. Besides, each baseband channel can be transparently upconverted to multiple radio-frequency (RF) bands for different wireless standards, which can be flexibly filtered at the end user to select the on-demand RF band, depending on the wireless applications. For demonstration, we transmit a 2.5 Gbit∕s signal through the proposed system and successfully achieve a bit-error-rate (BER) performance well below the 7% overhead forward error correction limit of the BER of 2 × 10−3 for both the wireline and the wireless signals in the 60 GHz band after 25 km single-mode fiber plus up to 6 m wireless distance.This work was supported in part by the EU Commission within the WISCON project of the Marie Curie Program and the FP7 ICT-249142 FIVER, as well as the Spain Plan Nacional ULTRADEF project.Pang, X.; Beltrán, M.; Sánchez Vílchez, JM.; Pellicer, E.; Olmos, JJV.; Llorente Sáez, R.; Monroy, IT. (2014). Centralized Optical-Frequency-Comb-Based RF Carrier Generator for DWDM Fiber-Wireless Access Systems. IEEE/OSA Journal of Optical Communications and Networking. 6(1):1-7. https://doi.org/10.1364/JOCN.6.0000011761Prince, K., Jensen, J. B., Caballero, A., Xianbin Yu, Gibbon, T. B., Zibar, D., … Monroy, I. T. (2009). Converged Wireline and Wireless Access Over a 78-km Deployed Fiber Long-Reach WDM PON. IEEE Photonics Technology Letters, 21(17), 1274-1276. doi:10.1109/lpt.2009.2025699Kuri, T., Toda, H., & Kitayama, K. (2003). Dense wavelength-division multiplexing millimeter-wave-band radio-on-fiber signal transmission with photonic downconversion. Journal of Lightwave Technology, 21(6), 1510-1517. doi:10.1109/jlt.2003.812465Jianjun Yu, Jinxing Gu, Xiang Liu, Zhensheng Jia, & Gee-Kung Chang. (2005). Seamless integration of an 8/spl times/2.5 Gb/s WDM-PON and radio-over-fiber using all-optical up-conversion based on Raman-assisted FWM. IEEE Photonics Technology Letters, 17(9), 1986-1988. doi:10.1109/lpt.2005.853526Zhensheng Jia, Jianjun Yu, & Gee-Kung Chang. (2005). All-optical 16 /spl times/ 2.5 Gb/s WDM signal simultaneous up-conversion based on XPM in an NOLM in ROF systems. IEEE Photonics Technology Letters, 17(12), 2724-2726. doi:10.1109/lpt.2005.859168Jia, Z., Yu, J., Ellinas, G., & Chang, G.-K. (2007). Key Enabling Technologies for Optical–Wireless Networks: Optical Millimeter-Wave Generation, Wavelength Reuse, and Architecture. Journal of Lightwave Technology, 25(11), 3452-3471. doi:10.1109/jlt.2007.909201Shih, P.-T., Lin, C.-T., Jiang, W.-J., Chen, J. (Jyehong), Huang, H.-S., Chen, Y.-H., … Chi, S. (2009). WDM up-conversion employing frequency quadrupling in optical modulator. Optics Express, 17(3), 1726. doi:10.1364/oe.17.001726Jianjun Yu, Zhensheng Jia, Lei Xu, Lin Chen, Ting Wang, & Gee-Kung Chang. (2006). DWDM optical millimeter-wave generation for radio-over-fiber using an optical phase modulator and an optical interleaver. IEEE Photonics Technology Letters, 18(13), 1418-1420. doi:10.1109/lpt.2006.877226Olmos, J. J. V., Kuri, T., Sono, T., Tamura, K., Toda, H., & Kitayama, K. (2008). Reconfigurable 2.5-Gb/s Baseband and 60-GHz (155-Mb/s) Millimeter-Waveband Radio-Over-Fiber (Interleaving) Access Network. Journal of Lightwave Technology, 26(15), 2506-2512. doi:10.1109/jlt.2008.927162Moraitis, N., & Constantinou, P. (2006). Measurements and characterization of wideband indoor radio channel at 60 GHz. IEEE Transactions on Wireless Communications, 5(4), 880-889. doi:10.1109/twc.2006.1618937Chen, C., Zhang, C., Liu, D., Qiu, K., & Liu, S. (2012). Tunable optical frequency comb enabled scalable and cost-effective multiuser orthogonal frequency-division multiple access passive optical network with source-free optical network units. Optics Letters, 37(19), 3954. doi:10.1364/ol.37.003954Chen, C., Jin, W., Zhang, C. F., Qiu, K., & Zhang, W. (2013). Hybrid WDM-OFDMA-PON utilising tunable generation of flat optical comb. Electronics Letters, 49(4), 276-277. doi:10.1049/el.2013.0031Wu, R., Supradeepa, V. R., Long, C. M., Leaird, D. E., & Weiner, A. M. (2010). Generation of very flat optical frequency combs from continuous-wave lasers using cascaded intensity and phase modulators driven by tailored radio frequency waveforms. Optics Letters, 35(19), 3234. doi:10.1364/ol.35.003234Islam, A. H. M. R., Bakaul, M., Nirmalathas, A., & Town, G. E. (2012). Simplification of millimeter-wave radio-over-fiber system employing heterodyning of uncorrelated optical carriers and self-homodyning of RF signal at the receiver. Optics Express, 20(5), 5707. doi:10.1364/oe.20.005707Xiaodan Pang, Caballero, A., Dogadaev, A., Arlunno, V., Deng, L., Borkowski, R., … Tafur Monroy, I. (2012). 25 Gbit/s QPSK Hybrid Fiber-Wireless Transmission in the W-Band (75–110 GHz) With Remote Antenna Unit for In-Building Wireless Networks. IEEE Photonics Journal, 4(3), 691-698. doi:10.1109/jphot.2012.2193563Lie-Liang Yang. (2006). MIMO-assisted space-code-division multiple-access: linear detectors and performance over multipath fading channels. IEEE Journal on Selected Areas in Communications, 24(1), 121-131. doi:10.1109/jsac.2005.85889

Evaluation of highly adsorptive Guefoams (multifunctional guest-containing foams) as a potential sorbent for determination of volatile organic compounds (VOCs) by means of thermal desorption

The present work delves into the feasibility of employing a novel structured sorbent referred to as GFAD (Guefoam Adsorption Device) for the determination of volatile organic compounds (VOCs) in liquid samples. The chosen method has been static headspace sorptive extraction-thermal desorption gas chromatography mass spectrometry (HSSE-TD-GC–MS). The GFAD comprises an aluminum cellular material with a distinct replication structure and a solid guest phase consisting of activated carbon particles dispersed within the cavities of the cellular aluminum. The extensive specific surface area, robustness, and exceptional thermal conductivity of this pioneering material offer distinct advantages over commercially available polydimethylsiloxane-based Twister® devices. Therefore, the trapping efficiency for volatile organic compounds is enhanced, and it is possible to perform the analysis of concentrated samples. According to computational simulations, it has been demonstrated that GFAD has a high heat conductivity. As a result, the desorption efficiency is improved, and minimal temperature gradients are generated throughout the GFAD during the heating process. Besides, the energy consumption is significantly lowered, thus aligning with environmentally conscientious and sustainable analytical practices. The experimental results give a proof of the suitability of the GFAD for determining gaseous compounds in liquid samples through HSSE-TD-GC–MS. For volatile species, the new material provides higher peak areas and lower limits of detection than a commercially available Twister® device. Furthermore, the GFAD is reusable, its adsorbing properties remaining unchanged during, at least, 100 consecutive analyses. In addition, unlike to the Twister®, no intense siloxane peaks are observed in the chromatograms obtained with the GFAD. The feasibility of qualitative and semi-quantitative analysis with the new accessory has been demonstrated with both standards and a cereal bioethanol real sample.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. The research leading to these results received funding from Spanish Ministry of Science, Innovation, and Universities under Grant Agreement No PID2021-127566NB-I00

Propuesta de redacción de cláusula de arreglo directo en un contrato comercial, que no tenga la sanción de ineficacia de pleno derecho contemplada en el artículo 13 del código general del proceso

Propuesta de redacción de cláusula de arreglo directo en un contrato comercial, que no tenga la sanción de ineficacia de pleno derecho contemplada en el artículo 13 del código general del proceso.A proposal for the wording of a direct arrangement clause in a commercial contract, that does not have the sanction of inefficiency of full right referred to in article 13 of the general process codeEspecialista en Derecho ComercialEspecializació

Multielemental analysis of oils and animal fat by using deep eutectic solvents assisted by an aerosol phase extraction procedure

In the present study, thirteen elements (Ag, Al, Ba, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Ni, Pb) have been extracted from used cooking oils, olive oils and animal fat. Either inductively coupled plasma optical emission spectrometry (ICP-OES) or tandem mass spectrometry (ICP-MS/MS) have been chosen as detection techniques. Due to the difficulty of directly introducing highly viscous organic samples into the spectrometer, a fast dispersive liquid – liquid aerosol phase extraction (DLLAPE) method has been selected to isolate the analytes from the sample matrix. The DLLAPE is based on the generation of an aerosol from the extracting phase with the help of a pneumatic nebulizer. This high velocity aerosol impacts and penetrates in the liquid sample. Consequently, the liquid – liquid exchange surface area becomes high, thus leading to high extraction yields. A hydrophilic deep eutectic solvent (DES) consisting of choline chloride and ethylene glycol (1:2 mass ratio) has been selected as the extracting solvent. Prior to undertaking the experiments, the extraction method has been evaluated in terms of precision under suitable conditions. In comparison with conventional methods based on sample digestion, sample dilution and shot analysis or extraction assisted by vortex agitation, the DLLAPE shows several advantages, because it is faster, and it provides lower limits of detection than the reference methodologies. The procedural limits of quantification for the determined elements with the DLLAPE in ICP-OES were 0.046 (Ag), 0.396 (Al), 0.013 (Cd), 0.033 (Cr), 0.040 (Cu), 0.20 (Fe), 0.026 (K), 0.026 (Li), 0.33 (Mg), 0.013 (Mn), 2.64 (Ni) and 0.53 (Pb) mg kg−1. Meanwhile, pLOQ in ICP-MS/MS lowered by roughly one order of magnitude. The accuracy of the aerosol phase extraction method has been evaluated through the determination of the recoveries for four representative analytes (Ca, Cu, Mg and Ni) from spiked real samples. For these elements, recovery has taken values of (100 ± 20)%. Moreover, a comparison of the multielemental concentration obtained with conventional methods (c.a., sample dilution and shot ICP analysis and liquid-liquid extraction using a vortex agitator) against that measured with the DLLAPE has been carried out. Multiemelemental concentrations have been obtained for real samples and the found levels have been similar to those encountered in previously published works.The authors wish to thank to the Spanish Ministry of Science, Innovation and Universities for the financial support (Projects Ref. PID2021-127566NB-I00 and PID2021-127322NB-100)