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We spectroscopically analyzed a sample of 85 Sloan Digital Sky Survey compact, oxygen-dominated galaxies located at redshift z ∼ 0.001–0.350, selected because of their large equivalent width of [O iii ] λ 5007 (larger than 200 Å). These galaxies might be considered as extreme emission-line galaxies due to their strong [O iii ] λ 5007 emission line. We detected high-ionization lines, even those related to the presence of Wolf–Rayet stars, in almost all the galaxies studied. We obtained physical properties (electron density and temperature) as well as chemical abundances by using the direct method based on the electron temperature. In this analysis, we obtained three different measurements of T ( high ): the usual one, T ([O iii ]), but also that of T ([S iii ]) and T ([Ar iii ]) for five and three of the galaxies, respectively. Further, we established a new calibration for T ([S iii ]). We determined oxygen, nitrogen, sulfur, neon, argon, iron, and chlorine abundances when possible, and we compared to the results of other late-type, low-metallicity galaxies, such as blue compact dwarfs, Ims, and green peas. From such a detailed study, we can conclude that the majority of the galaxies in this sample have similar metallicities to the SMC (about $12+\mathrm{log}({\rm{O}}/{\rm{H}}$ ) ≈ 8 dex), and that only 12% of the galaxies are extremely metal-poor, with abundances lower than 7.7 dex. Also, a comparison with some chemical evolution models as well as a brief discussion on the chemical evolution with time is considered.

Early-life stages play a key role in the dynamics of bipartite life cycle marine fish populations. Difficult to monitor, observations of these stages are often scattered in space and time. While Mediterranean coastlines have often been surveyed, no effort has been made to assemble historical observations. Here we build an exhaustive compilation of dispersal traits for coastal fish species, considering in situ observations and growth models (Di Stefano et al., 2023; https://doi.org/10.17882/91148). Our database contains over 110 000 entries collected from 1993 to 2021 in various subregions. All observations are harmonized to provide information on dates and geolocations of both spawning and settlement, along with pelagic larval durations. When applicable, missing data and associated confidence intervals are reconstructed from dynamic energy budget theory. Statistical analyses allow traits’ variability to be revisited and sampling biases to be revealed across taxa, space and time, hence providing recommendations for future studies and sampling. Comparison of observed and modelled entries provides suggestions to improve the feed of observations into models. Overall, this extensive database is a crucial step to investigate how marine fish populations respond to global changes across environmental gradients.

Abstract The significant imbalances between human settlements and their surrounding environments, stemming from sector-specific policies and urban regional planning tools, constitute a primary factor in the resilience and responsiveness of territories in crisis scenarios. Within this context, the promotion of territorial heritage values emerges as a crucial means for the reactivation of vulnerable areas. Furthermore, the utilisation of technological resources, such as Geographic Information Systems (GIS), has proven to be highly effective in managing cultural landscape areas. This contribution aims to enhance the valorisation of territorial heritage through the geolocation of a system of architectural and archaeological assets of public interest, and by enabling the flexible design of cultural itineraries within the framework of slow tourism. For this purpose, a replicable methodology for the construction of a WebGIS application has been proposed. This methodology has been put into practice in the territorial area of the lower Guadalquivir River in Spain, which encompasses 73 municipalities and one UNESCO World Heritage Site, all interconnected by rural areas. A four-stage plan has been followed for the construction of the VIDA-HTL web application: (1) conceptualisation; (2) development; (3) technical verification; and (4) social viability. The fundamental approach of the web application is based on the comprehensive integration of subsystems related to cultural heritage on one hand, and to tourist and environmental services on the other. Two main functions for the exploration of cultural assets and designing cultural routes have been designed, which complement other capabilities implemented in the web application. As a result of a detailed standardisation process, 981 cultural assets and 43 supplementary data layers have been georeferenced and included in the web application, with customised itineraries available for planning within the study area. Additionally, 49 thematic cultural itineraries are proposed. Finally, the web application is complemented with the development of a collaborative hub, which encourages its use and enhances its capabilities. It is concluded that digital tools, such as that proposed, foster knowledge and valorisation of territorial cultural heritage, while contributing to greater local development. In this way, they function as a counterbalance to the development of metropolises and the global economy, thereby improving levels of regional resilience.

Neuronal dendrites form densely branched tree architectures through which mitochondria must be distributed to supply the cell's energetic needs. Dendritic mitochondria circulate across the tree, undergoing fusion and fission to form clusters of varying sizes. We present a mathematical model for the distribution of such actively driven interacting particles in a branched geometry, showing that the density and localization of particles is highly sensitive to the fusion/fission balance and to the tree architecture. Our model demonstrates that “balanced” trees (wherein cross-sectional area is conserved across junctions and thicker branches support more bushy subtrees) enable symmetric yet distally enriched particle distributions and promote dispersion into smaller clusters. These results highlight the importance of tree morphology and radius-dependent fusion in governing the distribution of neuronal mitochondria.

Catheter ablation (CA) remains the cornerstone alternative to cardioversion for sinus rhythm (SR) restoration in patients with atrial fibrillation (AF). Unfortunately, despite the last methodological and technological advances, this procedure is not consistently effective in treating persistent AF. Beyond introducing new indices to characterize the fibrillatory waves (f-waves) recorded through the preoperative electrocardiogram (ECG), the aim of this study is to combine frequency- and time-domain features to improve CA outcome prediction and optimize patient selection for the procedure, given the absence of any study that jointly analyzes information from both domains. Precisely, the f-waves of 151 persistent AF patients undergoing their first CA procedure were extracted from standard V1 lead. Novel spectral and amplitude features were derived from these waves and combined through a machine learning algorithm to anticipate the intervention mid-term outcome. The power rate index (φ), which estimates the power of the harmonic content regarding the dominant frequency (DF), yielded the maximum individual discriminant ability of 64% to discern between individuals who experienced a recurrence of AF and those who sustained SR after a 9-month follow-up period. The predictive accuracy was improved up to 78.5% when this parameter φ was merged with the amplitude spectrum area in the DF bandwidth (AMSALF) and the normalized amplitude of the f-waves into a prediction model based on an ensemble classifier, built by random undersampling boosting of decision trees. This outcome suggests that the synthesis of both spectral and temporal features of the f-waves before CA might enrich the prognostic knowledge of this therapy for persistent AF patients.

Ecuador is a country with several climate zones. However, their behaviour is similar throughout the year, with no peaks of extreme temperatures in the various seasons. This paper is a first approach to study the adaptive comfort behaviour in several areas and populations of the country. Considering the ASHRAE 55-2020 model, energy simulation programmes are applied not just to the current climate scenario but also to the climate change scenarios of 2050 and 2100. The results of locations are analysed and compared to determine their performance. Thanks to their climate characteristics, adaptive comfort models could be applied as a passive strategy, using natural ventilation for building indoor comfort improvement, particularly social dwellings. According to previous studies, some prototypes have not considered the climate determinants in each region. Given the geographic situation of the study areas, the adaptive comfort model could be applied in all cases. Percentages of application of natural ventilation and heating and cooling degree hours have similar behaviours according to the climatic region, with a variation greater than 30% among them.

Fruit consumption guarantees the supply of most of the necessary nutrients for a complete and balanced diet, as it is a relevant source of vitamins, minerals, and antioxidants. In particular, pomegranate has very interesting medicinal properties, such as an anti-inflammatory effect and the protection of the cardiovascular system, among others. During pomegranate juice production, it appears cloudy and must be clarified to remove suspended solids such as colloids and high-molecular weight tannins. The membrane clarification process is a cost-effective alternative to the conventional methods, resulting in a high-quality product. In this work, the clarification of pomegranate juice using the Triple System Model F1 membrane module was carried out for the Mollar and Wonderful varieties with early and late maturity. Three ultrafiltration membranes with different molecular weight cut-off and different chemical compositions were used. The rejection coefficient and permeate flux (which represent the selectivity of the membranes and the process efficiency, respectively) were measured. GR-40PP showed the best results in terms of membrane selectivity and process efficiency, achieving adequate physicochemical juice parameters. Regarding the comparison of the maturity degree, in general terms, the Mollar variety showed better results. Ripe pomegranates showed greater selectivity, while the process efficiency was higher for the early samples.

The removal of three emerging pollutants: carbamazepine, ketoprofen, and bisphenol A, has been studied using the nanofiltration flat sheet membrane NF99HF. The removal efficiencies of the membrane have been evaluated by two system characteristic parameters: permeate flux and rejection coefficient. The influence of two operating variables has been analysed: operating pressure and feed concentration. Before and after the tests with emerging pollutants, the membrane has been characterized by determining its water permeability coefficient and its magnesium chloride rejection coefficient to find out if the removal of emerging pollutants causes membrane fouling. The results show that operating pressure has significant separation effects, obtaining the highest efficiencies at a pressure of 20 bar for pollutant concentrations between 5 and 25 mg/L. Moreover, rejection of ketoprofen was found to be dependent on electrostatic repulsion, while rejection of bisphenol A was significantly affected by adsorption onto the membrane. Finally, the experimental data have been fitted to the solution diffusion model and to the simplified model of Spiegler-Kedem-Katchalsky to predict the behaviour of the nanofiltration membrane in the removal of the tested pollutants. Good agreement between the experimental and predicted carbamazepine and bisphenol A data has been obtained with each model, respectively.

Abstract This work describes the project submitted to the University-Society-Business 2021 call for proposals whose aim is to integrate the knowledge and university practices in the field of energy in buildings into secondary school students. The aim is to define the energy strategies to be implemented to strengthen the relationship between secondary education and university studies, by means of a "pilot project" at a secondary school, as well as to promote Science, Technology, Engineering and Maths (STEM) scientific vocations in young people, with particular emphasis on the female gender. The project will carry out an energetic study at a school developed by university research staff and secondary school students. The aim is to motivate and confirm the qualities of people in STEM teaching, to arouse interest and closeness as well as to promote education in the subject of energy efficiency in buildings

Conservation studies of an architectural asset constitute a solid support for future interventions. In particular, Digital Cartographic Management advocates the use of simplified models that allow different levels of definition to be achieved, depending on the desired architectural scale. Based on previous studies in which four levels of definition have been achieved, the aim is to define a fifth level from a 3D model. For this purpose, the Macarena Wall (Seville) is proposed as a case study. In this work, a photogrammetric survey of a section of the sector of this medieval wall is carried out, from which the entities that will form part of a fifth level of definition are identified.

In this work thermoeconomics is applied to a central thermal system covering three buildings that consists of a cogeneration engine, an aerothermal heat pump and a natural gas condensing boiler. Cogeneration systems integrated with renewable energy technologies are very attractive solutions in the building sector. Nevertheless, the use of cogeneration systems together with active envelope solutions, such as the one encountered in this work, are scarce and the efforts to enhance the synergies between both systems are even scarcer. A heat pump is connected to a so-called solar wall to provide hot air and a renewable photovoltaic system supplies the electricity consumed by the heat pump. Thermoeconomics is applied to evaluate the cost of flows based on its energy-quality. Hence, this innovative and complex system can be analysed and diagnosed by this methodology. As a result, thermoeconomics is presented as an effective tool for the detailed study of the energy cost distribution and the key to enhancing energy efficiency.

Background: When we experience an emotion, a personal evaluation of stimuli and physiological responses occurs, based on the previous exposure. Anger can be triggered when we feel upset by movies, and those more realistic as videos of the internet can be even more arousing. Measures can be obtained to estimate synchronous participation between two brain areas during the processing of emotions. Objective: We compare brain activity in response to fictional visual stimuli taken from a movie bank versus real internet videos. Methods: We recorded subjective responses, and electrophysiological parameters to compare the functional connectivity patterns of 26 young women divided into two groups. Results: Results showed differences of functional connectivity revealed a characteristic pattern associated with each type of video observed, with an increased electroencephalographic (EEG) correlation during observation of the internet videos and a decreased EEG correlation while watching the movie clips, between frontal and temporal regions in slow and fast bands. Conclusion: Functional connectivity EEG analysis, together with the subjetive physiological assessment, allow for a closer approach to the study of the cognitive processing of emotions.

There has been a rise in antibiotic resistance in secondary conditions such as Clostridium difficile (C. difficile) due to overuse of antibiotics. Oral antibiotics are used to treat C. difficile, which further disrupts the intestinal flora resulting in unwanted side effects. Naturopathic treatments often have fewer side effects and lower secondary infection risk than pharmaceutical interventions making them ideal for pediatric use. This case report describes the effective treatment of a pediatric clinical case of C. difficile using naturopathic and complementary alternative medicines (CAMs) including black seed oil (Nigella sativa), bentonite clay, and probiotics. A healthy two-year-old patient presented to a pediatrician with symptoms of, and subsequently confirmed, C. difficile after having been recently hospitalized and treated for a gluteal abscess and cellulitis using clindamycin, vancomycin, and piperacillin/tazobactam. Through a shared decision-making process, the patient’s mother and providers developed a treatment plan for the C. difficile infection (CDI), which included black seed oil, bentonite clay, and Lactobacillus probiotics. No C. difficile was detected via stool immunoassay after 4 days of combined CAM therapy. Our results underscore the need for additional research regarding the effectiveness of naturopathic CAMs including black seed oil, bentonite clay, and probiotics as alternatives to antibiotic treatment of CDI in children.

Esse trabalho apresenta uma avaliação crítica multicontextual, histórica e conceitual, do Princípio de Pascal nos livros didáticos de Física aprovados no Programa Nacional do Livro Didático (PNLD) 2018. A análise realizada levou em consideração os seguintes aspectos: o enunciado do Princípio de Pascal sob o ponto de vista conceitual; relações entre ciência e tecnologia, tendo em vista dispositivos relacionados ao Princípio; fontes históricas primárias e secundárias relacionadas ao desenvolvimento do Princípio de Pascal; fundamentação historiográfica e apontamentos da legislação educacional para a inserção didática da História e da Filosofia da Ciência. Foram notadas inconsistências no que diz respeito à aplicabilidade do Princípio de Pascal, visões simplistas sobre a ciência e sobre as relações entre ciência e tecnologia, distorções históricas, anacronismos e abordagens historicamente descontextualizadas. Em face do referido cenário, são apontadas sugestões para uma inserção didática mais adequada.

Introduction: HaNDL syndrome (transient headache and neurological deficits with cerebrospinal fluid lymphocytosis) is characterised by one or more episodes of headache and transient neurological deficits associated with cerebrospinal fluid lymphocytosis. To date, few cases of HaNDL manifesting with confusional symptoms have been described. Likewise, very few patients with HaNDL and confusional symptoms have been evaluated with transcranial Doppler ultrasound (TCD). TCD data from patients with focal involvement reveal changes consistent with vasomotor alterations. Development: We present the case of a 42-year-old man who experienced headache and confusional symptoms and displayed pleocytosis, diffuse slow activity on EEG, increased blood flow velocity in both middle cerebral arteries on TCD, and single-photon emission computed tomography (SPECT) findings suggestive of diffuse involvement, especially in the left hemisphere. Conclusions: To our knowledge, this is the first description of a patient with HaNDL, confusional symptoms, diffuse slow activity on EEG, and increased blood flow velocity in TCD. Our findings suggest a relationship between cerebral vasomotor changes and the pathophysiology of HaNDL. TCD may be a useful tool for early diagnosis of HaNDL. Resumen: Introducción: El síndrome de cefalea y déficits neurológicos transitorios con pleocitosis en líquido cefalorraquídeo (acrónimo en inglés, HaNDL) se caracteriza por la presencia de uno o más episodios de cefalea y déficits neurológicos transitorios asociados con linfocitosis en líquido cefalorraquídeo. Hasta la fecha actual se han reportado escasos episodios de HaNDL con clínica compatible con cuadro confusional, y no se encuentran descritas mediciones de Doppler transcraneal (DTC) en pacientes afectos de HaNDL y cuadro confusional. En los registros DTC realizados en pacientes con afectación focal se han objetivado datos indicativos de alteraciones vasomotoras. Desarrollo: Presentamos el caso clínico y los resultados de pruebas complementarias de un varón de 42 años afecto de cefalea, síndrome confusional, pleocitosis, electroencefalograma (EEG) con enlentecimiento difuso, DTC con elevación de velocidades en ambas arterias cerebrales medias y tomografía computarizada por emisión de fotón único compatible con afectación difusa de predominio hemisférico izquierdo. Conclusiones: Aportamos a la literatura el primer paciente descrito que aúna síndrome de HaNDL, cuadro confusional, EEG compatible con afectación difusa y DTC con aceleración de velocidades. Nuestros hallazgos sugieren una relación entre las alteraciones vasomotoras y la fisiopatología del HaNDL, y consideramos que el DTC es una herramienta útil para el diagnóstico precoz del HaNDL. Keywords: HaNDL, Pseudomigraine with pleocytosis, Acute confusional syndrome, Cerebral vasomotor changes, Transcranial Doppler, Cannabis and cocaine use, Palabras clave: HaNDL, Pseudomigraña con pleocitosis, Síndrome confusional, Vasoespasmo, Doppler transcraneal, Consumo de cannabis y cocaína

The presence of pharmaceutical products, and their metabolites, in wastewater has become a focus of growing environmental concern. Among these pharmaceutical products, ibuprofen (IBU) is one of the most consumed non-steroidal anti-inflammatory drugs and it can enter the environment though both human and animal consumption, because it is not entirely absorbed by the body, and the pharmaceutical industry wastewater. Nanofiltration has been described as an attractive process for the treatment of wastewater containing pharmaceutical products. In this paper, the modification of a polysulfone nanofiltration membrane by coating with graphene oxide (GO) and reduced graphene oxide (RGO) has been carried out. The morphology and elemental composition of the active layer of unmodified and modified membranes were analyzed by scanning electronic microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. Initial characterization membranes was carried out, studying their water permeability coefficient and their permeate flux and rejection coefficients, at different applied pressures, using magnesium chloride solutions. The behavior of both pristine and coated membranes against ibuprofen solutions were analyzed by studying the permeate fluxes and the rejection coefficients at different pressures and at different contaminant concentrations. The results have shown that both GO and RGO coated membranes lead to higher values of ibuprofene rejection than that of uncoated membrane, the latter being the one that presents better results in the studies of permeability, selectivity, and fouling.

Sperm vitrification has been recently developed, but fertility trials have not been performed yet in equine species. In this study, a new warming technique for vitrified donkey semen was developed and the uterine inflammatory response and fertility were compared to conventional freezing. In Experiment 1, sperm was vitrified in straws and warmed in 3 ml of extender or in a water bath at: 37 °C/30 s; 43 °C/10 s; and 60 °C/5 s. Sperm motility, plasma and acrosome membranes and DNA integrity were compared between treatments. In Experiment 2, jennies were inseminated twice (500 × 106 sperm) in the uterine body either with vitrified or frozen semen (2 cycles/jenny). Pregnancy rates and the uterine inflammatory response (polymorphonuclear neutrophil concentration; PMN) were evaluated after artificial insemination (AI). No differences between warming in extender/water bath were found and 43 °C/10 s was better than lower temperatures in terms of total (53.8 ± 13.2%) and progressive sperm motility (41.4 ± 11.4%). No differences in PMN concentration (×103 PMN/ml) were found between vitrified (276.8 ± 171.6) or frozen (309.7 ± 250.7) semen after AI. However, PMN decreased faster (P

Colorectal cancer (CRC) is one of the most common and recurrent types of cancer, with high mortality rates. Several clinical trials and meta-analyses have determined that the use of pharmacological inhibitors of cyclooxygenase 2 (COX-2), the enzyme that catalyses the rate-limiting step in the synthesis of prostaglandins (PG) from arachidonic acid, can reduce the incidence of CRC as well as the risk of recurrence of this disease, when used together with commonly used chemotherapeutic agents. These observations suggest that inhibition of COX-2 may be useful in the treatment of CRC, although the current drugs targeting COX-2 are not widely used since they increase the risk of health complications. To overcome this difficulty, a possibility is to identify genes regulated by COX-2 activity that could give an advantage to the cells to form tumors and/or metastasize. The modulation of those genes as effectors of COX-2 may cancel the beneficial effects of COX-2 in tumor transformation and metastasis. A review of the available databases and literature and our own data have identified some interesting molecules induced by prostaglandins or COX-2 that have been also described to play a role in colon cancer, being thus potential pharmacological targets in colon cancer. Among those mPGES-1, DUSP4, and 10, Programmed cell death 4, Trop2, and many from the TGFβ and p53 pathways have been identified as genes upregulated in response to COX-2 overexpression or PGs in colon carcinoma lines and overexpressed in colon tumor tissue. Here, we review the available evidence of the potential roles of those molecules in colon cancer in the context of PG/COX signaling pathways that could be critical mediators of some of the tumor growth and metastasis advantage induced by COX-2. At the end, this may allow defining new therapeutic targets/drugs against CRC that could act specifically against tumor cells and would be effective in the prevention and treatment of CRC, lacking the unwanted side effects of COX-2 pharmacological inhibitors, providing alternative approaches in colon cancer.

Despite their indisputable efficacy for pain management, opiate prescriptions remain highly controversial partially due to their elevated addictive potential. Relapse in drug use is one of the principal problems for addiction treatment, with drug-associated memories being among its main triggers. Consequently, the extinction of these memories has been proposed as a useful therapeutic tool. Hence, by using the conditioned place aversion (CPA) paradigm in rats, we investigated some of the molecular mechanisms that occurr during the retrieval and extinction of morphine withdrawal memories in the basolateral amygdala (BLA) and the hippocampal dentate gyrus (DG), which control emotional and episodic memories, respectively. The retrieval of aversive memories associated with the abstinence syndrome paralleled with decreased mTOR activity and increased Arc and GluN1 expressions in the DG. Additionally, Arc mRNA levels in this nucleus very strongly correlated with the CPA score exhibited by the opiate-treated rats. On the other hand, despite the unaltered mTOR phosphorylation, Arc levels augmented in the BLA. After the extinction test, Arc and GluN1 expressions were raised in both the DG and BLA of the control and morphine-treated animals. Remarkably, Homer1 expression in both areas correlated almost perfectly with the extinction showed by morphine-dependent animals. Moreover, Arc expression in the DG correlated strongly with the extinction of the CPA manifested by the group treated with the opiate. Finally, our results support the coordinated activity of some of these neuroplastic proteins for the extinction of morphine withdrawal memories in a regional-dependent manner. Present data provide evidence of differential expression and activity of synaptic molecules during the retrieval and extinction of aversive memories of opiate withdrawal in the amygdalar and hippocampal regions that will likely permit the development of therapeutic strategies able to minimize relapses induced by morphine withdrawal-associated aversive memories.

Clean biofuels are a helpful tool to comply with strict emission standards. The co-processing approach seems to be a compromise solution, allowing the processing of partially bio-based feedstock by utilizing existing units, overcoming the need for high investment in new infrastructures. We performed a model co-processing experiment using vacuum gas oil (VGO) mixed with different contents (0%, 30%, 50%, 70%, 90%, and 100%) of rapeseed oil (RSO), utilizing a nickel–tungsten sulfide catalyst supported on acid-modified phonolite. The experiments were performed using a fixed-bed flow reactor at 420 °C, a hydrogen pressure of 18 MPa, and a weight hourly space velocity (WHSV) of 3 h−1. Surprisingly, the catalyst stayed active despite rising oxygen levels in the feedstock. In the liquid products, the raw diesel (180–360 °C) and jet fuel (120–290 °C) fraction concentrations increased together with increasing RSO share in the feedstock. The sulfur content was lower than 200 ppm for all the products collected using feedstocks with an RSO share of up to 50%. However, for all the products gained from the feedstock with an RSO share of ≥50%, the sulfur level was above the threshold of 200 ppm. The catalyst shifted its functionality from hydrodesulfurization to (hydro)decarboxylation when there was a higher ratio of RSO than VGO content in the feedstock, which seems to be confirmed by gas analysis where increased CO2 content was found after the change to feedstocks containing 50% or more RSO. According to the results, NiW/acid-modified phonolite is a suitable catalyst for the processing of feedstocks with high triglyceride content.

The Fischer–Tropsch heavy fraction is a potential feedstock for transport-fuels production through co-processing with fossil fuel fraction. However, there is still the need of developing new and green catalytic materials able to process this feedstock into valuable outputs. The present work studies the co-hydrocracking of the Fisher–Tropsch heavy fraction (FT-res.) with vacuum gas oil (VGO) at different ratios (FT-res. 9:1 VGO, FT-res. 7:3 VGO, and FT-res. 5:5 VGO) using phonolite-based catalysts (5Ni10W/Ph, 5Ni10Mo/Ph, and 5Co10Mo/Ph), paying attention to the overall conversion, yield, and selectivity of the products and properties. The co-processing experiments were carried out in an autoclave reactor at 450 °C, under 50 bars for 1 and 2 h. The phonolite-based catalysts were active in the hydrocracking of FT-res.:VGO mixtures, presenting different yields to gasoline, diesel, and jet fuel fractions, depending on the time of reaction and type of catalyst. Our results enable us to define the most suitable metal transition composition for the phonolite-based support as a hydrocracking catalyst.

The need to find alternative liquid fuels more environmental friendly and with a more secure supply, has led to the idea of studying the conversion of carbonaceous wastes, like plastics, used tyres and biomass into liquid products to be used as fuels or as raw materials for several industries. As coal liquefaction is a well-known process to produce liquid products, coal blended with used tyres and plastic wastes was co-liquefied. Coal impregnated with 1 % wt. of molybdenum was used in co-liquefaction tests blended with 50 % wt. of used tyres or with the main plastics present in municipal solid wastes: PE (polyethylene), PP (polypropylene), PS (polystyrene) and a mixture of these plastics. The results obtained showed that all wastes promoted coal liquefaction. However, liquids yield and quality improved with the presence of plastics, while more solids were obtained when used tyres were used. Coal blends with PS wastes led to the highest liquid yield (74 % wt.) and conversion (88 % wt.) The presence of PE favoured the formation of linear alkanes, while PS promoted the formation of more aromatic compounds, which is in agreement with these plastics initial molecular structure. Some co-liquefaction tests were done in presence of tetralin, a hydrogen donor solvent that promoted the formation of liquids. Tetralin allowed increasing liquids yields obtained with plastics to values higher than 90 % wt., while in co-liquefaction of coal with used tyres led to liquids yields around 77 % wt.

Embryo transfer and the vitrification of embryos could be used for the conservation and recovery of endangered donkey breeds. It is important to develop techniques that optimize recovery rates and the cryotolerance of donkey embryos. This study evaluates factors affecting the recovery rate, quality, and diameter of embryos obtained from donor jennies as a starting point for the use of vitrification and embryo transfer in the conservation of the Andalusian donkey. A total of 100 embryos were recovered out of 124 estrous cycles (80.6%). The donor jenny affected the rates of positive flushings (PFR; p = 0.040) and embryo recovery (ERR; p < 0.05) as well as embryo quality (p = 0.004). ERR was also affected by the number of flushings (p < 0.001), donor age (p < 0.05), successive cycle within donor (p < 0.001), and jacks (p < 0.05). Number of flushings (p < 0.001) and jack (p < 0.05) had a significant effect on PFR, whereas the day of flushing influenced the developmental stage (p < 0.001), embryo quality (p < 0.05), and diameter of embryos (p < 0.001). The number of flushings significantly influenced the diameter (p = 0.038) and embryo developmental stage (p = 0.001), whereas the developmental stage was statistically different between herds (p = 0.020). The factors influencing the success of this assisted reproductive technique were donor jenny, donor age, successive cycle within donor, day of flushing, number of flushings, and jack. The identification of these key points is crucial to achieve a higher efficiency of embryo transfer and vitrification processes, before considering their application in the conservation of endangered donkey breeds.

It is predictable that liquid fuels will be needed for long distance transport sector for quite some years. Thus, it is imperative to find alternative fuels to reduce the dependency on petroleum derived fuels and to decrease the negative environmental impact. Co-liquefaction of coal and wastes, like plastics, to produce liquid fuels and raw materials for several industries may play an important role in the near future, because it will decrease the problems associated with the dependency of only one raw material and also it will allow taking profit of the suitable properties of each one, while diluting the disadvantageous characteristics of coal. The use of plastics, namely polyethylene (PE) favoured coal liquefaction, as PE macromolecules are easier to break down and to form smaller liquid molecules than coal. To improve the production of liquid compounds by coal liquefaction solvents with different hydrogen donor capabilities were tested, such as: methylnaphthalene and tetralin. Tetralin led to the highest liquid yields and conversion, due to its hydrogen donor capacity. Some commercial available catalysts, like FCC (Fluid Catalytic Cracking) and Co-Mo based were also tried. Coal impregnated with some metals like iron (Fe) and molybdenum (Mo) was also tested. Impregnated coal, especially with Mo showed to have a better performance than the commercial catalysts. Liquid yield obtained during co-liquefaction of coal and PE when coal was impregnated with Mo was around 66 wt%. The use of tetralin allowed increasing this value around 44 %.

El asfalto tiene complejas composiciones químicas y físicas que normalmente varían con la fuente del petróleo crudo. Su composición se basa en aproximadamente 84% C, 10% H2, 1% O2 y 5% trazas de elementos como S, Ni, V y Fe. El propósito de esta investigación es desarrollar un método para cuantificar V, Ni, Zn y Fe en asfalto AC-30 por espectroscopia de absorción atómica. La investigación propone un procedimiento de tratamiento de hasta 2 g de asfalto, el cual se basa en su dilución con solvente orgánico (mineral spirits) en balones aforados con ayuda de un baño ultrasónico para aligerar la dilución. Se dictan los parámetros de optimización del método buscando los datos instrumentales adecuados en el equipo de absorción atómica para la obtención de la mayor absorbancia posible en la alineación tanto del quemador como de las lámparas de cátodo hueco y deuterio; además de la optimización de la llama y del flujo del nebulizador. Las curvas de calibración de cada metal se realizaron con un estándar con base de hidrocarburos para medir las concentraciones de metales en el asfalto en mg/kg con un coeficiente de correlación lineal de mínimo 0.995. El estudio de recuperación en asfalto se realiza con la adición de una cantidad de los metales directamente a las alícuotas de matriz de asfalto. Las concentraciones obtenidas para el Ni fueron 70, V 330, Zn 24 y para Fe 10 ppm, los cuales presentaron una desviación estándar relativa inferiores al 1% lo que indica que las mediciones de una misma muestra son precisas y que presentan poca dispersión entre ellas. Las recuperaciones promedio fueron de 99.17% para Ni, 100.30% V, 92.26% Zn y 97.72% Fe. Estos resultados indican que el método resulta confiable para la cuantificación de metales mediante la técnica de absorción atómica