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Updated water directives and ambitious targets like the United Nations’ Sustainable Development Goals (SDGs) have emerged in the last decade to tackle water scarcity and contamination. Although numerous strategies have been developed to remove water pollutants, it is still necessary to enhance their effectiveness against toxic and biorefractory organic molecules. Comprehensive reviews have highlighted the appealing features of the electrochemical technologies, but much progress has been made in recent years. In this timely review, a critical discussion on latest innovations and perspectives of the most promising electrochemical tools for wastewater treatment is presented. The work describes the performance of electrocatalytic anodes for direct electrochemical oxidation, the oxidation mediated by electrogenerated active chlorine, the electrocatalytic reduction as well as coupled approaches for synchronous anodic and cathodic processes combined with homogeneous and heterogeneous catalysis. The last section is devoted to the assessment of scale-up issues and the increase in the technology readiness level.

Ozone (O3) is a powerful oxidant widely used in disinfection and wastewater treatment. In this work, a novel 3-D printed casing for electrochemical cells has been specially designed and manufactured for Proton-Exchange Membrane (PEM) electro-ozonizers, trying to promote an improved fluid dynamic including an efficient evacuation of gases produced during the electrolysis and aiming to minimize the interaction among ozone and scavengers. It is demonstrated that reaching high efficiencies in the electrochemical production of ozone is limited by the action of electrogenerated scavengers, among which cathodically formed hydrogen peroxide outstands. This explains the effects observed regarding current density (higher efficiencies at higher current densities applied, because hydrogen peroxide production is prevented), electrolyte composition (better efficiencies with lower concentrations of non-reacting electrolytes) and operation pressure (better results at lower pressures, because hydrogen peroxide formation depends more importantly on dissolved oxygen than ozone production). A very good performance is obtained, with ozone productions as high as 0.240 mg/(Ah cm2) and maximum current efficiencies of 5.9% under the best operation conditions (1.0 mM of HClO4, 330 mA/cm2 and 1 bar), which demonstrate the suitability of the technology tested and the good perspectives of 3D printing to improve performance of electrochemical processes., Ozono (O 3) es un poderoso oxidante ampliamente utilizado en desinfección y tratamiento de aguas residuales. En este trabajo, se ha diseñado y fabricado especialmente una carcasa impresa en 3D para celdas electroquímicas para electro-ozonizadores de membrana de intercambio de protones (PEM), tratando de promover una dinámica de fluidos mejorada que incluya una evacuación eficiente de los gases producidos durante la electrólisis y con el objetivo de minimizar la interacción entre el ozono y los secuestrantes. Se demuestra que alcanzar altas eficiencias en la producción electroquímica de ozono está limitado por la acción de secuestrantes electrogenerados, entre los que destaca el peróxido de hidrógeno formado catódicamente. Esto explica los efectos observados con respecto a la densidad de corriente (mayores eficiencias a mayores densidades de corriente aplicadas, porque se evita la producción de peróxido de hidrógeno), composición de electrolitos (mejores eficiencias con concentraciones más bajas de electrolitos que no reaccionan) y presión de operación (mejores resultados a presiones más bajas, porque la formación de peróxido de hidrógeno depende más del oxígeno disuelto que de la producción de ozono). Se obtiene un muy buen rendimiento, con producciones de ozono de hasta 0,240 mg/(Ah cm2 ) y eficiencias de corriente máximas del 5,9% en las mejores condiciones de operación (1,0 mM de HClO 4 , 330 mA/cm 2 y 1 bar), que demuestran la idoneidad de la tecnología probada y las buenas perspectivas de la impresión 3D para mejorar el rendimiento de procesos electroquimicos.

This paper evaluates the remediation of soil spiked with lindane using a combined treatment consisting of electrokinetic soil flushing (EKSF) with air stripping to elucidate the main processes occurring in the soil when electric fields of 0.75 V cm−1 and 1.50 V cm−1 are applied. The results demonstrate that lindane is efficiently transported to the anodic and cathodic wells using flushing fluids containing sodium dodecyl sulfate (SDS). Additionally, an important amount is volatilized and stripped with the injected air. In the cathodic well, lindane is rapidly transformed into other species because of the strongly alkaline media. These other species are also found in the portions of soil next to this well, confirming the efficient transport of chlorinated organics with SDS. After 14 days of operation, nearly 50% of the spiked lindane can be removed from the soil. Operation with large electric fields does not improve the performance of the treatment technology and results in lower current intensities and electro-osmotic fluxes and in higher evaporated water, despite the water content in the soil matrix, indicating the coexistence of multiple inputs in these processes. Graphical abstract

FLK North (FLK N) (Bed I, Olduvai Gorge, Tanzania) is one of the best examples of a palimpsest where felids, hyenids and hominins made use of the same space without or with minimal interaction between hominins and the other two carnivores. Felids have been interpreted as the main accumulators and carcass consumers followed by frequent hyenid intervention. The presence of hominins at this site has been documented through the discovery of stone tools. Here, we test previous taphonomic interpretations of this site through the application of Artificial Intelligence (AI) tools (computer vision applied to bidimensional images of tooth pits) to taxonomically discriminate carnivore-made tooth marks. The bones we analyzed constitute a small sample, being a preliminary study of bone surface modifications (BSM) through the application of AI to a sample of the FLK N archaeofaunal assemblage (mostly to Level 3 fossils), pending access to the larger excavated collections. The results obtained in the present study show that the marks analyzed have been generated both by hyenids and felids. The slight predominance of hyena tooth marks is expected, since the bone sample used is dominated by long limb bones, and hyenas are the most likely agent causing long bone breakage, although felids also break bones of carcasses smaller than 150 kg as documented in the site. Felid impact, in at least three cases, is documented with tooth marks imprinted by felids and hyenas occurring on the same specimens. Felid-hyenid interaction is, thus, documented though the deep learning methods applied. The limited number of specimens where both agents are documented suggest that both hyenids and felids were independently breaking a substantial part of the bones at FLK N. This preliminarily modifies previous interpretations that attributed most long bone fragmentation exclusively to hyenas.

Here, we present a thorough taphonomic analysis of the 1.84 million-year-old site of Phillip Tobias Korongo (PTK), Bed I, Olduvai Gorge. PTK is one of the new archaeological sites documented on the FLK Zinj paleolandscape, in which FLK 22 level was deposited and covered by Tuff IC. Therefore, PTK is pene- contemporary with these sites: FLK Zinj, DS, AMK and AGS. The occurrence of these sites within a thin clay unit of ~20 cm, occupying not only the same vertically discrete stratigraphic unit, but also the same paleosurface, with an exceptional preservation of the archaeological record in its primary depositional locus, constitutes a unique opportunity to explore early hominin behavioral diversity at the most limited geochronological scale possible. The Olduvai Bed I sites have been the core of behavioral modelling for the past half a century, and the newly discovered sites, excavated with 21st century technology, will increase significantly our understanding of early human adaptive patterns. Here, we present PTK as another assemblage where faunal resources were acquired by hominins prior to any carnivore, and where stone-tool assisted bulk defleshing was carried out. The abundance of juvenile individuals extends our understanding, as in Kanjera (Kenya), about the hunting skills of early Homo sensu lato. The increasing number of sites, where bulk defleshing of small and medium-sized carcasses took place is underscoring the importance of meat in the diets of some of the early hominins, and their patterned use of the space for food processing and consumption. The patterning emerging has a profound importance for the evolution of some of the features that have traditionally been used to identify the behavior of the genus Homo., This work was supported by the Swedish Research Council (Vetenskapsrådet) (AR-HS 2018-01045-3). We also thank the Spanish Ministry of Science and Innovation for funding this research (PID 2020-115452 GB-C21), and the Ministry of Culture for their funding through the program of Archaeology Abroad. Our thanks also to the Palarq Foundation and E2in2 for financial support.

The major raw material documented in the archaeological sites of Olduvai Gorge (Tanzania) is a geological material with crystalline appearance, white or colorless, foliated or seemingly massive only at the outcrop scale, with a very high quartz-rich composition, and apparently bearing a metamorphic origin (CQRM). Since the early days of research in Olduvai Gorge, a long-lasting terminological imprecision has allowed defining this material in a confused way as quartz or quartzite. Stubbornness in terminological imprecision reflects the complexity and specificity of CQRM related to a protracted and complex geological history composed by quartz-bearing metamorphic rocks of varied types and origins from recycling and/or tectonic reworking of much older Precambrian orogens and cratons. Currently the term quartzite is preferred by most researchers, despite being materials that have an appearance macro and microscopic similar to quartz and show a response to fracture mechanics and cutting-edge functional response is closer to quartz. In our view it is crucial to undertake a comprehensive analysis of the CQRM from the structural, metamorphic and petrological perspectives. Bearing this in mind, the main objective of the present study is to build a robust and conclusive background that will enable an accurate identification and classification of this quartz-rich mineral resource. This geological material should be identified as “Quartz” and he most diagnostic features supporting this interpretation can be summarized as: some of the microstructural relics identified concur undoubtedly with a hydrothermal origin, and the recognition of special deformational structures/microstructures point to tectono-metamorphic processes under granulite-facies conditions.

In this work, the performance of a reversible electrochemical cell using three different electrodes (Ti/Ru0.5Ir0.5O2, Ti/Ru0.3Ti0.7O2, and Ti/Ru0.3Ti0.6O2Pt0.1) is evaluated and compared for the oxidation of chlorides and reduction of chlorine. Results indicate that this technology is successful and that its efficiency depends significantly on the composition of the electrode in charge of the chlorine electrochemistry. Operating at 0.5 V allows us to obtain near 7 mA cm−2 and power efficiencies around 120 Wh mmol−1 hydrogen supplied. In electrolytic mode, efficiencies around 4 mol Cl2 mWh−1 can be obtained. The best performance is shown by the Ti/Ru0.3Ti0.6O2Pt0.1 electrode resulting from its roughest morphology and the presence of Pt. In shifting from electrolyzer to fuel cell mode, the current produced is rapidly stabilized for Ti/Ru0.3Ti0.6O2Pt0.1 and Ti/Ru0.5Ir0.5O2 electrodes. However, the electrode Ti/Ru0.5Ir0.5O2 showed a progressive change, which suggests a change in its composition that negatively affects the system., En este trabajo se evalúa y compara el desempeño de una celda electroquímica reversible utilizando tres electrodos diferentes (Ti/Ru 0.5 Ir 0.5 O 2 , Ti/Ru 0.3 Ti 0.7 O 2 , y Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 ). para la oxidación de cloruros y reducción de cloro. Los resultados indican que esta tecnología es exitosa y que su eficiencia depende significativamente de la composición del electrodo a cargo de la electroquímica del cloro . Operando a 0,5 V nos permite obtener cerca de 7 mA cm −2y eficiencias energéticas de alrededor de 120 Wh mmol- 1 de hidrógeno suministrado. En modo electrolítico se pueden obtener eficiencias en torno a 4 mol Cl 2 mWh− 1 . El electrodo Ti/Ru 0.3 Ti 0.6 O 2 Pt 0.1 presenta el mejor comportamiento debido a su morfología más rugosa ya la presencia de Pt. Al pasar del modo electrolizador al modo de pila de combustible, la corriente producida se estabiliza rápidamente para los electrodos Ti/Ru 0,3 Ti 0,6 O 2 Pt 0,1 y Ti/Ru 0,5 Ir 0,5 O 2 . Sin embargo, el electrodo Ti/Ru0.5 Ir 0.5 O 2 mostró un cambio progresivo, lo que sugiere un cambio en su composición que afecta negativamente al sistema.

The depletion of blaKPC (K. pneumoniae), blaOXA-50 (P. aeruginosa) and mecA (S. aureus) genes from hospital urines is evaluated to contribute to solve the silent pandemic of antibiotic-resistance bacteria. A microfluidic flow-through reactor with MMO anode and CB/PTFE cathode working at 50 A m−2 is employed during electrodisinfection and photo-electrodisinfection processes. The electrodisinfection process only achieves an almost negligible removal of DNA and slightly log ARG increments of 0.18, 0.19 and 0.71 for blaOXA-50, mecA and blaKPC genes, respectively. Conversely, the photo-electrodisinfection process attains the complete disinfection for all ARB tested and logarithmic removals of 3.70, 2.25 and 0.82 for blaOXA-50, mecA and blaKPC genes, respectively. These outcomes emphasize the potential of the UV light coupled to the electrodisinfection process to promote the formation of not only hypochlorite but also chlorine and even nitrogen radicals, which contribute to enhance the disinfection efficiency of the target ARB and their ARGs., Se evalúa la depleción de los genes bla KPC ( K. pneumoniae ), bla OXA-50 ( P. aeruginosa ) y mec A ( S. aureus ) de orinas hospitalarias para contribuir a solucionar la pandemia silenciosa de bacterias resistentes a los antibióticos. Se emplea un reactor de flujo continuo de microfluidos con ánodo MMO y cátodo CB/PTFE que trabaja a 50 A m - 2 durante los procesos de electrodesinfección y fotoelectrodesinfección. El proceso de electrodesinfección solo logra una eliminación casi insignificante de ADN y aumentos ligeramente logarítmicos de ARG de 0,18, 0,19 y 0,71 para bla OXA-50 , mec A y bla KPCgenes, respectivamente. Por el contrario, el proceso de fotoelectrodesinfección logra la desinfección completa para todos los ARB probados y eliminaciones logarítmicas de 3,70, 2,25 y 0,82 para los genes bla OXA-50 , mec A y bla KPC , respectivamente. Estos resultados enfatizan el potencial de la luz ultravioleta junto con el proceso de electrodesinfección para promover la formación no solo de hipoclorito sino también de radicales de cloro e incluso nitrógeno, que contribuyen a mejorar la eficiencia de desinfección del ARB objetivo y sus ARG.

The composition and concentration of airborne microorganisms in hospital indoor air has been reported to contain airborne bacteria and fungi concentrations ranged 101–103 CFU/m3 in inpatients facilities which mostly exceed recommendations from the World Health Organization (WHO). In this work, a deeper knowledge of the performance of airborne microorganisms would allow improving the designs of the air-conditioning installations to restrict hospital-acquired infections (HAIs). A solution containing Escherichia coli (E. coli) as a model of airborne bacteria was nebulized using the Collison nebulizer to simulate bioaerosols in various hospital areas such as patients’ rooms or bathrooms. Results showed that the bioaerosol source had a significant influence on the airborne bacteria concentrations since 4.00 102, 6.84 103 and 1.39 104 CFU mL−1 were monitored during the aerosolization for 10 min of urine, saliva and urban wastewater, respectively. These results may be explained considering the quite narrow distribution profile of drop sizes around 1.10–1.29 μm obtained for urban wastewater, with much vaster distribution profiles during the aerosolization of urine or saliva. The airborne bacteria concentration may increase up to 107 CFU mL−1 for longer sampling times and higher aerosolization pressures, causing several cell damages. The cell membrane damage index (ID) can vary from 0 to 1, depending on the genomic DNA releases from bacteria. In fact, the ID of E. coli was more than two times higher (0.33 vs. 0.72) when increasing the pressure of air flow was applied from 1 to 2 bar. Finally, the ventilation air flow also affected the distribution of bioaerosols due to its direct relationship with the relative humidity of indoor air. Specifically, the airborne bacteria concentration diminished almost below 3-logs by applying more than 10 L min−1 during the aerosolization of urine due to their inactivation by an increase in their osmotic pressure., La composición y concentración de los microorganismos transportados por el aire en el interior de los hospitales contiene concentraciones de bacterias y hongos que oscilan entre 101 y 103 UFC/m3 en los centros de hospitalización, que en la mayoría de los casos superan las recomendaciones de la Organización Mundial de la Salud (OMS). En este trabajo, un conocimiento más profundo del comportamiento de los microorganismos transportados por el aire permitiría mejorar los diseños de las instalaciones de aire acondicionado para restringir las infecciones adquiridas en el hospital (HAI). Se nebulizó una solución que contenía Escherichia coli (E. coli) como modelo de bacteria aerotransportada utilizando el nebulizador Collison para simular bioaerosoles en diversas áreas hospitalarias, como las habitaciones o los baños de los pacientes. Los resultados mostraron que la fuente del bioaerosol tenía una influencia significativa en las concentraciones de bacterias aerotransportadas, ya que se monitorizaron 4,00 102, 6,84 103 y 1,39 104 UFC mL-1 durante la aerosolización durante 10 minutos de orina, saliva y aguas residuales urbanas, respectivamente. Estos resultados pueden explicarse considerando el perfil de distribución bastante estrecho de tamaños de gota alrededor de 1,10-1,29 μm obtenido para las aguas residuales urbanas, con perfiles de distribución mucho más amplios durante la aerosolización de orina o saliva. La concentración de bacterias en el aire puede aumentar hasta 107 UFC mL-1 para tiempos de muestreo más largos y presiones de aerosolización más altas, causando varios daños celulares. El índice de daño de la membrana celular (ID) puede variar de 0 a 1, dependiendo de la liberación de ADN genómico de las bacterias. De hecho, el ID de E. coli fue más de dos veces superior (0,33 frente a 0,72) al aumentar la presión del flujo de aire de 1 a 2 bares. Por último, el flujo de aire de ventilación también afectó a la distribución de los bioaerosoles debido a su relación directa con la humedad relativa del aire interior. Concretamente, la concentración de bacterias en el aire disminuyó casi por debajo de 3 logs al aplicar más de 10 L min-1 durante la aerosolización de la orina debido a su inactivación por un aumento de su presión osmótica.

This paper focuses on the evaluation of the mobility of four hexachlorocyclohexane (HCH) isomers by soil vapor extraction (SVE) coupled with direct electrokinetic (EK) treatment without adding flushing fluids. SVE was found to be very efficient and remove nearly 70 % of the four HCH in the 15-days of the tests. The application of electrokinetics produced the transport of HCH to the cathode by different electrochemical processes, which were satisfactorily modelled with a 1-D transport equation. The increase in the electric field led to an increase in the transport of pollutants, although 15 days was found to be a very short time for an efficient transportation of the pollutants to the nearness of the cathode. Loss of water content in the vicinity of the cathode warns about the necessity of using electrokinetic flushing technologies instead of simple direct electrokinetics. Thus, results point out that direct electrokinetic treatment without adding flushing fluids produced low current intensities and ohmic heating that contributes negatively to the performance of the SVE process. No relevant differences were found among the removal of the four isomers, neither in SVE nor in EK processes.

This paper is focused on the evaluation of the electrochemically assisted absorption process (electro-absorption) as a treatment for volatile organic compounds contained in polluted air flows. Benzene degradation was used to test the technology, using a system consisting of a packed absorption column and a single compartment electrochemical cell equipped with boron-doped diamond (BDD) as anode and steel-steal as cathode. The influence of inlet gas flow rate and operation current intensity was evaluated by monitoring the concentration of benzene and intermediates both, in the liquid absorbent / electrolyte and in the outlet gaseous stream. Results show that steady-state values reached, during benzene absorption and electro-absorption, increase when the inlet gas flow rises from 1.5 to 6.0 L h−1 and that the bare absorption process retains benzene only up to this steady-state value of the liquid and then, it has no effect on the removal of benzene. Concentrations of benzene in the absorbent/electrolyte decreases with the increase in the current density during electrochemically assisted processes. As well, mineralization was found to be very important, as expected because of the very low concentrations of benzene into the liquid and the very high efficiencies of the electrolytic degradation with BDD electrodes, and benzoquinone and carboxylic acids were identified as the primary intermediates. These species were not detected in the outlet gas flow. The decrease in the concentration and mass flow of benzene in the outlet streams confirms that electro-absorption is a functional electrochemical application to remove benzene from gaseous streams. When current density rises (10, 50 and 100 mA cm−2), the degradation percentage increases. The values obtained were 43, 61 and 75% with 1,5 L h−1 of inlet gas flow and 10, 25 and 37 % with 6 L h−1. However, the degradation percentage relative to the energy consumption decreases when the current density rises. Results were, correspondingly, 24.7, 4.2 and 2.2 % kWh−1 with 1,5 L h−1 of inlet gas flow and 7.1, 2.1 and 1.4 % with 6 L h−1. This energy efficiency trend was explained because mass transport becomes the bottleneck in the oxidation of diluted organic solutions. These results contribute to expand the understanding of the mechanisms involved in the electro-absorption of benzene and recommend for further research in the topic, due to the relevance of the treatment results., Este artículo se centra en la evaluación del proceso de absorción electroquímicamente asistido (electroabsorción) como tratamiento de compuestos orgánicos volátiles contenidos en flujos de aire contaminado. La degradación del benceno se utilizó para probar la tecnología, utilizando un sistema que consiste en una columna de absorción empacada y una celda electroquímica de un solo compartimento equipada con diamante dopado con boro (BDD) como ánodo y acero como cátodo. La influencia del caudal de gas de entrada y la intensidad de la corriente de operación se evaluó monitoreando la concentración de benceno e intermedios tanto en el líquido absorbente/electrolito como en la corriente gaseosa de salida. Los resultados muestran que los valores de estado estacionario alcanzados, durante la absorción de benceno y la electroabsorción, aumentan cuando el flujo de gas de entrada aumenta de 1,5 a 6,0 L h −1y que el proceso de absorción simple retiene benceno solo hasta este valor de estado estacionario del líquido y luego, no tiene efecto en la eliminación de benceno. Las concentraciones de benceno en el absorbente/electrolito disminuyen con el aumento de la densidad de corriente durante los procesos asistidos electroquímicamente. Además, se encontró que la mineralización era muy importante, como se esperaba debido a las concentraciones muy bajas de benceno en el líquido y las eficiencias muy altas de la degradación electrolítica con electrodos BDD, y se identificaron la benzoquinona y los ácidos carboxílicos como los intermediarios primarios. Estas especies no se detectaron en el flujo de gas de salida. La disminución de la concentración y el flujo másico de benceno en las corrientes de salida confirma que la electroabsorción es una aplicación electroquímica funcional para eliminar el benceno de las corrientes gaseosas. Cuando aumenta la densidad de corriente (10, 50 y 100 mA cm−2 ), el porcentaje de degradación aumenta. Los valores obtenidos fueron 43, 61 y 75 % con 1,5 L h -1 de caudal de gas de entrada y 10, 25 y 37 % con 6 L h -1 . Sin embargo, el porcentaje de degradación relativo al consumo de energía disminuye cuando aumenta la densidad de corriente. Los resultados fueron, correspondientemente, 24,7, 4,2 y 2,2 % kWh- 1 con 1,5 L h - 1 de caudal de gas de entrada y 7,1, 2,1 y 1,4 % con 6 L h- 1. Esta tendencia de eficiencia energética se explica porque el transporte masivo se convierte en el cuello de botella en la oxidación de soluciones orgánicas diluidas. Estos resultados contribuyen a ampliar la comprensión de los mecanismos involucrados en la electroabsorción del benceno y recomiendan para futuras investigaciones en el tema, debido a la relevancia de los resultados del tratamiento.

Human carnivory is atypical among primates. Unlike chimpanzees and bonobos, who are known to hunt smaller monkeys and eat them immediately, human foragers often cooperate to kill large animals and transport them to a safe location to be shared. While it is known that meat became an important part of the hominin diet around 2.6–2 Mya, whether intense cooperation and food sharing developed in conjunction with the regular intake of meat remains unresolved. A widespread assumption is that early hominins acquired animal protein through klepto-parasitism at felid kills. This should be testable by detecting felid-specific bone modifications and tooth marks on carcasses consumed by hominins. Here, deep learning (DL) computer vision was used to identify agency through the analysis of tooth pits and scores on bones recovered from the Early Pleistocene site of DS (Bed I, Olduvai Gorge). We present the first objective evidence of primary access to meat by hominins 1.8 Mya by showing that the most common securely detectable bone-modifying fissipeds at the site were hyenas. The absence of felid modifications in most of the carcasses analyzed indicates that hominins were the primary consumers of most animals accumulated at the site, with hyenas intervening at the post-depositional stage. This underscores the role of hominins as a prominent part of the early Pleistocene African carnivore guild. It also stresses the major (and potentially regular) role that meat played in the diet that configured the emergence of early Homo.

Here, we present the first three-dimensional taphonomic analysis of a carnivore-modified assemblage at the anatomical scale of the appendicular skeleton. A sample of ten carcasses composed of two taxa (zebra and wildebeest) consumed by wild lions in the Tarangire National Park (Tanzania) has been used to determine element-specific lion damage patterns. This study presents a novel software for the 3D spatial documentation of bone surface modifications at the anatomical level. Combined with spatial statistics, the present analysis has been able to conclude that despite variable degrees of competition during carcass consumption, lions generate bilateral patterning consisting of substantial damage of proximal ends of stylopodials and zeugopodials, moderate damage of the distal ends of femora and marginal damage of distal ends of humeri and zeugopodials. Of special interest is, specifically, the patterning of tooth marks on shafts according to element, since these are crucial to determine not only the type of carnivore involved in any given bone assemblage, but also the interaction with other agents (namely, hominins, in the past). Lions leave few tooth marks on mid-shaft sections, mostly concentrated on certain sections and orientations of stylopodials and, to a lesser extent, of the proximal tibia. Redundant occurrence of tooth marks on certain bone sections renders them as crucial to attest lion agency in carcass initial consumption. Indirectly, this can also be used to determine whether hominins ever acquired carcasses at lion kills.

This paper evaluates the combination of electrokinetic soil flushing (EKSF) with soil vapor extraction (SVE) for the removal of four hexachlorocyclohexane (HCH) isomers contained in a real matrix. Results demonstrate that the combination of EKSF and SVE can be positive, but it is required the application of high electric fields (3 V cm−1) in order to promote a higher temperature in the system, which improves the volatilization of the HCH contained in the system. Electrokinetic transport is also enhanced with the application of higher electric gradients, but these transport processes are slower than the volatilization processes, which are the primary in this system. Hence collection of species in the electrolyte wells is negligible as compared to the compound dragged with air by the SVE but the temperature increase demonstrates a good performance. Combination of EKSF with SVE can efficiently exhaust the four HCH isomers reaching a removal of more than 90% after 15 days of treatment (20% more than values attained by SVE) but it is required the application of high electric fields to promote a higher temperature in the system (to improve the volatilization) and EK transport (to improve the dragging). 1-D transport model can be easily used to estimate the average pore water velocity and the effective diffusion of each compound under the different experimental conditions tested., Este artículo evalúa la combinación de lavado electrocinético del suelo (EKSF) con extracción de vapor del suelo (SVE) para la eliminación de cuatro isómeros de hexaclorociclohexano (HCH) contenidos en una matriz real. Los resultados demuestran que la combinación de EKSF y SVE puede ser positiva, pero se requiere la aplicación de campos eléctricos elevados (3 V cm −1) con el fin de promover una mayor temperatura en el sistema, lo que mejora la volatilización del HCH contenido en el sistema. El transporte electrocinético también mejora con la aplicación de gradientes eléctricos más altos, pero estos procesos de transporte son más lentos que los procesos de volatilización, que son los principales en este sistema. Por lo tanto, la recolección de especies en los pozos de electrolito es insignificante en comparación con el compuesto arrastrado con aire por el SVE, pero el aumento de temperatura demuestra un buen desempeño. La combinación de EKSF con SVE puede agotar eficientemente los cuatro isómeros de HCH alcanzando una eliminación de más del 90 % después de 15 días de tratamiento (20 % más que los valores alcanzados por SVE) pero se requiere la aplicación de campos eléctricos elevados para promover una temperatura más alta en el sistema (para mejorar la volatilización) y transporte EK (para mejorar el arrastre). El modelo de transporte 1-D se puede usar fácilmente para estimar el promediola velocidad intersticial del agua y la difusión efectiva de cada compuesto bajo las diferentes condiciones experimentales probadas.