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Abstract The ISS rodent habitat has provided crucial insights into the impact of spaceflight on mammals, inducing symptoms characteristic of liver disease, insulin resistance, osteopenia, and myopathy. Although these physiological responses can involve the microbiome on Earth, host-microbiota interactions during spaceflight are still being elucidated. We explore murine gut microbiota and host gene expression in the colon and liver after 29 and 56 days of spaceflight using multiomics. Metagenomics revealed significant changes in 44 microbiome species, including relative reductions in bile acid and butyrate metabolising bacteria like Extibacter muris and Dysosmobacter welbionis. Functional prediction indicate over-representation of fatty acid and bile acid metabolism, extracellular matrix interactions, and antibiotic resistance genes. Host gene expression described corresponding changes to bile acid and energy metabolism, and immune suppression. These changes imply that interactions at the host-gut microbiome interface contribute to spaceflight pathology and that these interactions might critically influence human health and long-duration spaceflight feasibility.

Introduction: The relationship between the entorhinal cortex (EC) and the hippocampus has been studied by different authors, who have highlighted the importance of grid cells, place cells, and the trisynaptic circuit in the processes that they regulate: the persistence of spatial, explicit, and recent memory and their possible impairment with ageing. Objective: We aimed to determine whether older age causes changes in the size and number of grid cells contained in layer III of the EC and in the granular layer of the dentate gyrus (DG) of the hippocampus. Methods: We conducted post-mortem studies of the brains of 6 individuals aged 56–87 years. The brain sections containing the DG and the adjacent EC were stained according to the Klüver-Barrera method, then the ImageJ software was used to measure the individual neuronal area, the total neuronal area, and the number of neurons contained in rectangular areas in layer III of the EC and layer II of the DG. Statistical analysis was subsequently performed. Results: We observed an age-related reduction in the cell population of the external pyramidal layer of the EC, and in the number of neurons in the granular layer of the DG. Conclusion: Our results indicate that ageing causes a decrease in the size and density of grid cells of the EC and place cells of the DG. Resumen: Introducción: La relación entre la corteza entorrinal y el hipocampo ha sido estudiada por diferentes autores, que han destacado la importancia de las células de cuadrícula, las células de posicionamiento y la conexión trisináptica, en los procesos que regulan; la persistencia de la memoria espacial, explícita y reciente y su posible afección con envejecimiento. Objetivo: Observar si existen diferencias en el tamaño y número de células de cuadrícula contenidas en la lámina tres de la corteza entorrinal y en la capa granular del giro dentado del hipocampo de pacientes mayores. Metodología: Realizamos estudios post-mortem del cerebro de 6 sujetos de edades comprendidas entre los 56 y 87 años. Los cortes de cerebros que contenían el giro dentado (GD) del hipocampo y la corteza entorrinal (CE) adyacente se tiñeron con el método de Klüver- Barrera, después se midió, mediante el programa Image J, el área neuronal individual, el área neuronal total, así como el número de neuronas, contenidas en cuadrículas rectangulares a nivel de la lámina III del CE y la lámina II del GD y se lleva a cabo un análisis estadístico. Resultados: Se ha observado una reducción de la población celular de la capa piramidal externa de la CE, así como de las neuronas de la capa granular del giro dentado relacionada con el envejecimiento. Conclusión: Nuestros resultados indican que el envejecimiento produce una disminución en el tamaño y la densidad neuronal en las células de cuadricula del córtex entorrinal y de posicionamiento del giro dentado.

Resumen: Introducción: La relación entre la corteza entorrinal y el hipocampo ha sido estudiada por diferentes autores, que han destacado la importancia de las células de cuadrícula, las células de posicionamiento y la conexión trisináptica en los procesos que regulan: la persistencia de la memoria espacial, explícita y reciente, y su posible afección con el envejecimiento. Objetivo: Observar si existen diferencias en el tamaño y número de células de cuadrícula contenidas en la lámina iii de la corteza entorrinal y en la capa granular del giro dentado del hipocampo de pacientes mayores. Métodos: Realizamos estudios posmortem del cerebro de 6 sujetos de edades comprendidas entre los 56 y 87 años. Los cortes de cerebros que contenían el giro dentado del hipocampo y la corteza entorrinal adyacente se tiñeron con el método de Klüver-Barrera, después se midió, mediante el programa Image J, el área neuronal individual, el área neuronal total, así como el número de neuronas, contenidas en cuadrículas rectangulares a nivel de la lámina iii de la corteza entorrinal y la lámina ii del giro dentado y se llevó a cabo un análisis estadístico. Resultados: Se ha observado una reducción de la población celular de la capa piramidal externa de la corteza entorrinal, así como de las neuronas de la capa granular del giro dentado relacionada con el envejecimiento. Conclusión: Nuestros resultados indican que el envejecimiento produce una disminución en el tamaño y la densidad neuronal en las células de cuadrícula de la corteza entorrinal y de posicionamiento del giro dentado. Abstract: Introduction: The relationship between the entorhinal cortex and the hippocampus has been studied by different authors, who have highlighted the importance of grid cells, place cells, and the trisynaptic circuit in the processes that they regulate: the persistence of spatial, explicit, and recent memory and their possible impairment with ageing. Objective: We aimed to determine whether older age causes changes in the size and number of grid cells contained in layer III of the entorhinal cortex and in the granular layer of the dentate gyrus of the hippocampus. Methods: We conducted post-mortem studies of the brains of 6 individuals aged 56-87 years. The brain sections containing the dentate gyrus and the adjacent entorhinal cortex were stained according to the Klüver-Barrera method, then the Image J software was used to measure the individual neuronal area, the total neuronal area, and the number of neurons contained in rectangular areas in layer III of the entorhinal cortex and layer II of the dentate gyrus. Statistical analysis was subsequently performed. Results: We observed an age-related reduction in the cell population of the external pyramidal layer of the entorhinal cortex, and in the number of neurons in the granular layer of the dentate gyrus. Conclusion: Our results indicate that ageing causes a decrease in the size and density of grid cells of the entorhinal cortex and place cells of the dentate gyrus.

The coastal temperate rainforests (CTRs) of Chilean Patagonia are a valuable forest biome on Earth given their prominent role in biogeochemical cycling and the ecological value and dynamics of surface processes. The Patagonian CTRs are amongst the most carbon-rich biomes on Earth. Together with frequent landscape disturbances, these forests potentially allow for episodic and massive release or sequestration of carbon into and from the atmosphere. We argue that, despite their particular biogeographic, geochemical, and ecological roles, the Patagonian CTRs in particular and the global CTRs in general are not adequately represented in the current catalog listing critical zone observatories (CZOs). Here, we present the Pumalín CZO as the first of its kind, located in Pumalín National Park in northern Chilean Patagonia. We consider our CZO a representative end-member of undisturbed ecosystem functioning of the Patagonian CTRs. We have identified four core research themes for the Pumalín CZO around which our activities circle in an integrative, quantitative, and generic approach using a range of emerging techniques. Our methodological blend includes an environmental seismology that also fills a critical spatiotemporal scale in terms of monitoring critical zone and surface processes with a minimum intervention in those pristine forests. We aim to gain quantitative understanding of these topics: (1) carbon sink functioning; (2) biota-driven landscape evolution; (3) water, biogeological, and energy fluxes; and (4) disturbance regime understanding. Our findings highlight the multitude of active functions that trees in particular and forests in general may have on the entire cascade of surface processes and the concomitant carbon cycling. This highlights the importance of an integrated approach, i.e., “one physical system”, as proposed by Richter and Billings (2015), and accounts for the recent advances in pushing nature conservation along the Chilean coast.

Abstract The role of dietary patterns in the development of osteoporosis is unclear. The heel quantitative ultrasound (QUS) is a potential alternative to Dual X-Ray Absorptiometry. Nutrients, foods, dietary patterns and compliance to dietary guidelines were compared between the lowest and the highest tertiles of QUS parameters [Broadband Ultrasound Attenuation (BUA), Speed of Sound (SOS), Stiffness Index (SI)], using data from the OsteoLaus cohort. Participants in the highest tertiles of QUS parameters (385 for BUA, 397 for SOS, 386 for SI) were younger, of higher body weight, and had less major osteoporotic fractures. Women in the highest tertiles of SI and BUA consumed more fat (35.1 ± 0.4 vs 33.9 ± 0.4 and 34.9 ± 0.4 vs 33.8 ± 0.4 gr/day for SI and BUA, respectively, p

Evaluating the potential for crown fires remains a pivotal concern in wildfire management because it affects fire behavior, causing them to spread further. In this work, we propose a methodology to assess crown fire potential based on the tree connectivity at crown level from UAS (Unmanned Aircraft Systems)-based Structure-from-Motion Photogrammetry. The approach is usable in a large landscape with the aim of reducing crown fire potential by considering the spatial variability of fuels within a stand. The utilization of UAS for photogrammetry holds immense promise in transforming the approach to assessing and managing forest fires. This cutting-edge technology offers the potential to deliver highly precise and comprehensive data concerning forest structure and connectivity, thereby presenting a groundbreaking opportunity for enhanced forest fire analysis and control.

X-ray free-electron lasers (XFELs) deliver pulses of coherent X-rays on the femtosecond time scale, with potentially high repetition rates. While XFELs provide high peak intensities, both the intensity and the centroid of the beam fluctuate strongly on a pulse-to-pulse basis, motivating high-rate beam diagnostics that operate over a large dynamic range. The fast drift velocity, low X-ray absorption and high radiation tolerance properties of chemical vapour deposition diamonds make these crystals a promising candidate material for developing a fast (multi-GHz) pass-through diagnostic for the next generation of XFELs. A new approach to the design of a diamond sensor signal path is presented, along with associated characterization studies performed in the XPP endstation of the LINAC Coherent Light Source (LCLS) at SLAC. Qualitative charge collection profiles (collected charge versus time) are presented and compared with those from a commercially available detector. Quantitative results on the charge collection efficiency and signal collection times are presented over a range of approximately four orders of magnitude in the generated electron–hole plasma density.

Tomato commercialization in Mexican and Latin-American markets is economically affected by three main physical aspects of the fruit: ripening time, size, and mass. Digital image processing combined with mathematical models and machine learning approaches allows the development of prediction models to minimize fruit waste, among other applications. Particularly crossed validation, linear and non-linear adjustment by quadratic mean least error approximation, and digital image processing are used to obtain a post-harvest mass loss estimation model based upon the fruit’s area. A database for fruit characterization of 97,200 images and mass (kg) and area (cm2) measurement entries over a continuous post-harvest timeline of 54 days was considered in the methodology. Results from the linear (polynomial) adjustment model presented an efficiency of 94.65%, while the non-linear (exponential and potential) adjustment models gave in their turn efficiencies of 99.21 and 99.82%, respectively. It was concluded that the best mass loss estimation model was the potential adjustment one, with an approximation error of just 0.18% between actual and estimated data.

Introduction The prevalence of allergies in children has grown in last few decades. Allergies are very often associated with physical, mental, and emotional problems that could be detected through child’s behaviour and feelings. Objectives to describe and compare children’s behaviour (internalizing and externalizing) across a sample of children aged 6–11 years with and without allergic diseases. Methods This was a cross-sectional observational case-control study. A survey to 366 families (194 allergic cases and 172 controls), including a child behaviour checklist (CBCL) and a socio-demographic questionnaire with questions related to family, school education, health conditions and allergy symptoms, was administered. Results Children with a diagnosis of allergy showed higher scores in the overall CBCL score (standardised mean differences [SMD]= 0.47; confidence intervals [CI]: 0.26–0.68) and in the internalizing and externalizing factors (SMD=0.52 and SMD=0.36, respectively) than non-allergic children. Odds ratio (OR) analyses showed a higher risk (OR=2.76; 95% CI [1.61 to 4.72]) of developing a behavioural difficulty in children diagnosed with allergies. Age and level of asthma appear as modulatory variables. Conclusions Children aged 6–11 years diagnosed with allergies showed larger behavioural problems than non-allergic children. This relationship is stronger in internalizing behaviours. These findings suggest the importance of attending to them and treating them in the early stages of diagnosis to avoid future psychological disorders. Disclosure No significant relationships.

Introduction Technology-based interventions (TBIs), including computer and Internet-based interventions, mobile interventions, health applications, social media interventions, and interventions using technological devices, could become a useful, effective, accessible, and cost-effective approach (Berry et al., 2016; Firth, 2016) to complement conventional interventions for psychosis Objectives to compare TBIs with conventional interventions for psychosis, focusing mainly on functioning and quality of life. Methods The systematic review preceding this work was based on 58 RCT of TBIs for psychosis. We selected the studies that analyzed functioning (N = 23) and quality of life (N = 15). We calculated the standardized mean change (SMC) and applied a three-level model because there were several effect sizes within the same study. Results There were significant differences between TBIs and conventional interventions for functioning (d = 0.25, SE = 0.09, z = 2.72, p =

Petrophysical and mechanical rock properties are key parameters for the characterization of the deep subsurface in different disciplines such as geothermal heat extraction, petroleum reservoir engineering or mining. They are commonly used for the interpretation of geophysical data and the parameterization of numerical models and thus are the basis for economic reservoir assessment. However, detailed information regarding petrophysical and mechanical rock properties for each relevant target horizon is often scarce, inconsistent or distributed over multiple publications. Therefore, subsurface models are often populated with generalized or assumed values resulting in high uncertainties. Furthermore, diagenetic, metamorphic and hydrothermal processes significantly affect the physiochemical and mechanical properties often leading to high geological variability. A sound understanding of the controlling factors is needed to identify statistical and causal relationships between the properties as a basis for a profound reservoir assessment and modeling. Within the scope of the GEMex project (EU H2020, grant agreement no. 727550), which aims to develop new transferable exploration and exploitation approaches for enhanced and super-hot unconventional geothermal systems, a new workflow was applied to overcome the gap of knowledge of the reservoir properties. Two caldera complexes located in the northeastern Trans-Mexican Volcanic Belt – the Acoculco and Los Humeros caldera – were selected as demonstration sites. The workflow starts with outcrop analog and reservoir core sample studies in order to define and characterize the properties of all key units from the basement to the cap rock as well as their mineralogy and geochemistry. This allows the identification of geological heterogeneities on different scales (outcrop analysis, representative rock samples, thin sections and chemical analysis) enabling a profound reservoir property prediction. More than 300 rock samples were taken from representative outcrops inside the Los Humeros and Acoculco calderas and the surrounding areas and from exhumed “fossil systems” in Las Minas and Zacatlán. Additionally, 66 core samples from 16 wells of the Los Humeros geothermal field and 8 core samples from well EAC1 of the Acoculco geothermal field were collected. Samples were analyzed for particle and bulk density, porosity, permeability, thermal conductivity, thermal diffusivity, and heat capacity, as well as ultrasonic wave velocities, magnetic susceptibility and electric resistivity. Afterwards, destructive rock mechanical tests (point load tests, uniaxial and triaxial tests) were conducted to determine tensile strength, uniaxial compressive strength, Young's modulus, Poisson's ratio, the bulk modulus, the shear modulus, fracture toughness, cohesion and the friction angle. In addition, X-ray diffraction (XRD) and X-ray fluorescence (XRF) analyses were performed on 137 samples to provide information about the mineral assemblage, bulk geochemistry and the intensity of hydrothermal alteration. An extensive rock property database was created (Weydt et al., 2020; https://doi.org/10.25534/tudatalib-201.10), comprising 34 parameters determined on more than 2160 plugs. More than 31 000 data entries were compiled covering volcanic, sedimentary, metamorphic and igneous rocks from different ages (Jurassic to Holocene), thus facilitating a wide field of applications regarding resource assessment, modeling and statistical analyses.

Maintaining astronaut health throughout long-duration spaceflight is essential to the feasibility of a manned mission to Mars. The ground-based Mars500 experiment investigated long-duration health by isolating six astronauts for 520 days, the longest controlled human confinement study conducted to date. After 520 days, astronauts had uniform strength and lean body mass losses, and increased fasting plasma glucose, calprotectin, and neutrophil levels characteristic of intestinal inflammation but previous analyses revealed no common significant changes in gut microbiota. This study reanalysed data from early (days 7–45) and late (days 420–520) faecal samples and identified 408 exact sequence variants (ESVs), including 213 shared by all astronauts. Thirty-two ESVs were significantly differentially abundant over time, including depletion of keystone resistant starch degrading, anti-inflammatory and insulin sensitivity-associated species, such as Faecalibacterium prausnitzii, Ruminococcus bromii, Blautia luti, Anaerostipes hadrus, Roseburia faecis, and Lactobacillus rogosae, and enrichment of yet-to-be-cultured bacteria. Additionally, the extraordinary experimental confinement allowed observation of microbiota potentially shared between astronauts and their habitat. Forty-nine species were shared, representing 49% and 12% of the human and environmental microbiome diversity, respectively. These findings reveal the microbiota which significantly altered in relative abundance throughout confinement, including species known to influence inflammation and host glucose homeostasis consistent with astronaut symptoms. Identification of microbiome alterations after 520 days of isolation represents a missing piece connecting Mars500 astronaut physiological studies. Knowledge of the impact of long-term confinement upon the human microbiome helps to improve our understanding of how humans interact with their habitats and is a valuable step forward towards enabling long-duration spaceflight.

Abstract The composition of extracellular vesicles (EVs) is altered in many pathological conditions, and their molecular content provides essential information on features of parent cells and mechanisms of crosstalk between cells and organs. Metabolic Syndrome (MetS) is a cluster of clinical manifestations including obesity, insulin resistance, dyslipidemia and hypertension that increases the risk of cardiovascular disease and type 2 diabetes mellitus. Here, we investigated the crosstalk between liver and adipocytes by characterizing EVs secreted by primary hepatocytes isolated from Zucker rat model, and studied the effect they have on 3T3‐L1 adipocytes. We found that steatotic hepatocytes secrete EVs with significantly reduced exosomal markers in comparison with their lean counterpart. Moreover, proteomic analysis revealed that those EVs reflect the metabolic state of the parent cell in that the majority of proteins upregulated relate to fat metabolism, fatty acid synthesis, glycolysis, and pentose phosphate pathway. In addition, hepatocytes‐secreted EVs influenced lipolysis and insulin sensitivity in recipient 3T3‐L1 adipocytes. Untargeted metabolomic analysis detected alterations in different adipocyte metabolic pathways in cells treated with hepatic EVs. In summary, our work showed that steatosis has a significant impact in the amount and composition of EVs secreted by hepatocytes. Moreover, our data point to the involvement of hepatic‐EVs in the development of pathologies associated with MetS.

Introduction: Alcohol abuse has a high impact on the mortality and morbidity related to a great number of diseases and is responsible for the development of alcoholic liver disease (ALD). It remains challenging to detect and evaluate its severity, which is crucial for prognosis. Objective: In this work, we studied if urinary EVs (uEVs) could serve in diagnose and evaluate cirrhosis in ALD. Methods: uEVs characterization by cryo-electron microscopy (Cryo-EM), Nanoparticle Tracking Analysis (NTA) and Western blotting (WB) was performed in a cohort of 21 controls and 21 cirrhotic patients. Then, proteomics of urinary EVs (uEVs) was carried out in a second cohort of 6 controls and 8 patients in order to identify new putative biomarkers for cirrhosis in ALD. Results: uEVs concentration, size and composition were altered in cirrhotic patients. A total of 1304 proteins were identified in uEVs, and 90 of them were found to be altered in cirrhotic patients. Conclusions: uEVs could be considered as a tool and a supplier of new biomarkers for ALD, whose application would be especially relevant in chronic patients. Yet, further research is necessary to obtain more relevant result in clinical terms.

Liver is a unique organ in displaying a reparative and regenerative response after acute/chronic damage or partial hepatectomy, when all the cell types must proliferate to re-establish the liver mass. The NADPH oxidase NOX4 mediates Transforming Growth Factor-beta (TGF-β) actions, including apoptosis in hepatocytes and activation of stellate cells to myofibroblasts. Aim of this work was to analyze the impact of NOX4 in liver regeneration by using two mouse models where Nox4 was deleted: 1) general deletion of Nox4 (NOX4−/−) and 2) hepatocyte-specific deletion of Nox4 (NOX4hepKO). Liver regeneration was analyzed after 2/3 partial hepatectomy (PH). Results indicated an earlier recovery of the liver-to-body weight ratio in both NOX4−/− and NOX4hepKO mice and an increased survival, when compared to corresponding WT mice. The regenerative hepatocellular fat accumulation and the parenchyma organization recovered faster in NOX4 deleted livers. Hepatocyte proliferation, analyzed by Ki67 and phospho-Histone3 immunohistochemistry, was accelerated and increased in NOX4 deleted mice, coincident with an earlier and increased Myc expression. Primary hepatocytes isolated from NOX4 deleted mice showed higher proliferative capacity and increased expression of Myc and different cyclins in response to serum. Transcriptomic analysis through RNA-seq revealed significant changes after PH in NOX4−/− mice and support a relevant role for Myc in a node of regulation of proliferation-related genes. Interestingly, RNA-seq also revealed changes in the expression of genes related to activation of the TGF-β pathway. In fact, levels of active TGF-β1, phosphorylation of Smads and levels of its target p21 were lower at 24 h in NOX4 deleted mice. Nox4 did not appear to be essential for the termination of liver regeneration in vivo, neither for the in vitro hepatocyte response to TGF-β1 in terms of growth inhibition, which suggest its potential as therapeutic target to improve liver regeneration, without adverse effects.

Background: Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic cause of renal failure. For several decades, ADPKD was regarded as an adult-onset disease. In the past decade, it has become more widely appreciated that the disease course begins in childhood. However, evidence-based guidelines on how to manage and approach children diagnosed with or at risk of ADPKD are lacking. Also, scoring systems to stratify patients into risk categories have been established only for adults. Overall, there are insufficient data on the clinical course during childhood. We therefore initiated the global ADPedKD project to establish a large international pediatric ADPKD cohort for deep characterization. Methods: Global ADPedKD is an international multicenter observational study focusing on childhood-diagnosed ADPKD. This collaborative project is based on interoperable Web-based databases, comprising 7 regional and independent but uniformly organized chapters, namely Africa, Asia, Australia, Europe, North America, South America, and the United Kingdom. In the database, a detailed basic data questionnaire, including genetics, is used in combination with data entry from follow-up visits, to provide both retrospective and prospective longitudinal data on clinical, radiologic, and laboratory findings, as well as therapeutic interventions. Discussion: The global ADPedKD initiative aims to characterize in detail the most extensive international pediatric ADPKD cohort reported to date, providing evidence for the development of unified diagnostic, follow-up, and treatment recommendations regarding modifiable disease factors. Moreover, this registry will serve as a platform for the development of clinical and/or biochemical markers predicting the risk of early and progressive disease. Keywords: ADPKD, ADPedKD Registry, children, longitudinal

Abstract Background The emergence and spread of antibiotic resistant micro-organisms is a global concern, which is largely attributable to inaccurate prescribing of antibiotics to patients presenting with non-bacterial infections. The use of ‘omics’ technologies for discovery of novel infection related biomarkers combined with novel treatment algorithms offers possibilities for rapidly distinguishing between bacterial and viral infections. This distinction can be particularly important for patients suffering from lower respiratory tract infections (LRTI) and/or sepsis as they represent a significant burden to healthcare systems. Here we present the study details of the TAILORED-Treatment study, an observational, prospective, multi-centre study aiming to generate a multi-parametric model, combining host and pathogen data, for distinguishing between bacterial and viral aetiologies in children and adults with LRTI and/or sepsis. Methods A total number of 1200 paediatric and adult patients aged 1 month and older with LRTI and/or sepsis or a non-infectious disease are recruited from Emergency Departments and hospital wards of seven Dutch and Israeli medical centres. A panel of three experienced physicians adjudicate a reference standard diagnosis for all patients (i.e., bacterial or viral infection) using all available clinical and laboratory information, including a 28-day follow-up assessment. Nasal swabs and blood samples are collected for multi-omics investigations including host RNA and protein biomarkers, nasal microbiota profiling, host genomic profiling and bacterial proteomics. Simplified data is entered into a custom-built database in order to develop a multi-parametric model and diagnostic tools for differentiating between bacterial and viral infections. The predictions from the model will be compared with the consensus diagnosis in order to determine its accuracy. Discussion The TAILORED-Treatment study will provide new insights into the interplay between the host and micro-organisms. New host- or pathogen-related biomarkers will be used to generate a multi-parametric model for distinguishing between bacterial and viral infections. This model will be helpful to better guide antimicrobial therapy for patients with LRTI and sepsis. This study has the potential to improve patient care, reduce unnecessary antibiotic prescribing and will contribute positively to institutional, national and international healthcare economics. Trial Registration NCT02025699. Registration Date: January, 1, 2014.

Dans un contexte de développement durable et intégré, il serait souhaitable de limiter le recours au génie civil en gestion du risque inondation et privilégier des solutions plus respectueuses des écosystèmes. Cependant, tous les auteurs ne sont pas d'accord sur l'efficacité des actions en versant sur le ruissellement pour atténuer les inondations. Pour appréhender ces désaccords, nous présentons d'abord quelques clés de compréhension des phénomènes de ruissellement, plus complexes qu'il n'y paraît à comprendre et à quantifier, surtout à l'échelle du bassin versant qui convient pour une stratégie de prévention des inondations. Ensuite, il apparaît que les actions en versant, dont la plantation de haies, laminent les ruissellements jusqu'à une certaine intensité, et qu'il faut se méfier des généralisations. Il ne s'agit pas d'écarter les actions en versant, mais bien d'en préciser les limites. Enfin, il faut replacer la notion d'intérêt ou d'efficacité dans un contexte multi-objectifs. Les acteurs ont des priorités différentes. Il leur appartient de définir ensemble leur méthodologie d'analyse multicritères, ainsi que des critères pour chacun des effets - hydrologiques (sur l'érosion, les inondations locales ou à l'aval, la quantité et la qualité de l'eau), patrimoniaux, environnementaux....

Abstract Background One method for rejuvenating land polluted with anthropogenic contaminants is through phytoremediation, the reclamation of land through the cultivation of specific crops. The capacity for phytoremediation crops, such as Salix spp., to tolerate and even flourish in contaminated soils relies on a highly complex and predominantly cryptic interacting community of microbial life. Methods Here, Illumina HiSeq 2500 sequencing and de novo transcriptome assembly were used to observe gene expression in washed Salix purpurea cv. ‘Fish Creek’ roots from trees pot grown in petroleum hydrocarbon-contaminated or non-contaminated soil. All 189,849 assembled contigs were annotated without a priori assumption as to sequence origin and differential expression was assessed. Results The 839 contigs differentially expressed (DE) and annotated from S. purpurea revealed substantial increases in transcripts encoding abiotic stress response equipment, such as glutathione S-transferases, in roots of contaminated trees as well as the hallmarks of fungal interaction, such as SWEET2 (Sugars Will Eventually Be Exported Transporter). A total of 8252 DE transcripts were fungal in origin, with contamination conditions resulting in a community shift from Ascomycota to Basidiomycota genera. In response to contamination, 1745 Basidiomycota transcripts increased in abundance (the majority uniquely expressed in contaminated soil) including major monosaccharide transporter MST1, primary cell wall and lamella CAZy enzymes, and an ectomycorrhiza-upregulated exo-β-1,3-glucanase (GH5). Additionally, 639 DE polycistronic transcripts from an uncharacterised Enterobacteriaceae species were uniformly in higher abundance in contamination conditions and comprised a wide spectrum of genes cryptic under laboratory conditions but considered putatively involved in eukaryotic interaction, biofilm formation and dioxygenase hydrocarbon degradation. Conclusions Fungal gene expression, representing the majority of contigs assembled, suggests out-competition of white rot Ascomycota genera (dominated by Pyronema), a sometimes ectomycorrhizal (ECM) Ascomycota (Tuber) and ECM Basidiomycota (Hebeloma) by a poorly characterised putative ECM Basidiomycota due to contamination. Root and fungal expression involved transcripts encoding carbohydrate/amino acid (C/N) dialogue whereas bacterial gene expression included the apparatus necessary for biofilm interaction and direct reduction of contamination stress, a potential bacterial currency for a role in tripartite mutualism. Unmistakable within the metatranscriptome is the degree to which the landscape of rhizospheric biology, particularly the important but predominantly uncharacterised fungal genetics, is yet to be discovered.

The COVID-19 pandemic forced more than 50 million students and their families to adapt to remote schooling. Most disrupted were communities of color, who faced multiple and overlapping inequalities in digital and equipment access, exposing and exacerbating existing disparities. Conducted in a small rural school district, this study surveyed the experiences of rural Spanish-speaking Latino caregivers. A total of 104 caregivers responded to a survey assessing caregiver digital literacy and access, school support, caregiver-teacher relationship and communication, and caregiver values, expectations, and teaching efficacy. Findings highlighted wide disparities in digital access and availability of equipment or devices compared to recent reports of more affluent White caregivers. Findings also highlighted that strong caregiver-teacher relationships were important for helping caregivers to navigate children's instruction during remote instruction. While student learning losses have yet to be fully assessed, hints at the full impact of school closures for rural linguistically and culturally diverse families are available from other countries, and they suggest that learning losses will be much greater for children from disadvantaged families than the population at large.

This study was part of a larger three-year investigation of the effectiveness of a small-group, content-focused (science, social studies) preschool shared book reading vocabulary intervention implemented with Spanish-speaking emergent bilinguals enrolled in a one-way dual-language bilingual program. A subset of bilingual preschool teachers (N = 23), representing treatment teachers from each of the three intervention years, was observed to understand the sustainability of the curricular approach and materials one, two, and three years post-intervention when instructional guidance was no longer provided by the research team. Findings from post-intervention observations and teacher self-reports suggest that teachers continued to implement the intervention approach and materials on some level but the explicit rich vocabulary instruction during the book reading experience was observed less the further teachers were out of the intervention. Implications for research are discussed.

In the United States, schools provide a large portion of child and adolescent mental health services; however, systems are restricted by resource and workforce shortages while the need for services steadily increases. This discrepancy leads to unmanageable caseloads for providers and reduced access to quality services for youth, and highlights a need to expand the school-based workforce to meet student needs. Herein, we propose a novel mental health service-delivery framework to offset these challenges by integrating mentors within the context of multitiered systems of support (MTSS) through task-shifting. We review and synthesize the literature in community and school psychology on the promises and challenges of youth mentoring and MTSS. We discuss the importance of diversifying school psychology, including the importance of increasing access to and benefit from educational supports for minoritized students, and the promise of mentoring within this context. We propose that by systematically integrating youth mentoring within MTSS there are several systems-level and individual-level benefits for youth, school staff, and mentoring nonprofits. We conclude by providing ethical, evaluation, and implementation considerations surrounding the proposed model. Impact Statement: Restructuring the school-based mental health workforce by integrating community mentors into MTSS frameworks provides an innovative, powerful way to engage with diverse student populations. We propose a novel model that expands and strengthens this workforce, thereby increasing the quality and reach of school-based services.

Understanding the chemistry of heavy radioactive elements is crucial to harnessing them for fuel and medicine. Here, the authors combine advanced X-ray spectroscopy and modelling to the study the chemical bonding of the 5fvalence orbitals of uranium, neptunium and plutonium.

After many years of rigid conventional procedures of production, industrial manufacturing is going through a process of change toward flexible and intelligent manufacturing, the so-called Industry 4.0. In this paper, human-robot collaboration has an important role in smart factories since it contributes to the achievement of higher productivity and greater efficiency. However, this evolution means breaking with the established safety procedures as the separation of workspaces between robot and human is removed. These changes are reflected in safety standards related to industrial robotics since the last decade, and have led to the development of a wide field of research focusing on the prevention of human-robot impacts and/or the minimization of related risks or their consequences. This paper presents a review of the main safety systems that have been proposed and applied in industrial robotic environments that contribute to the achievement of safe collaborative human-robot work. Additionally, a review is provided of the current regulations along with new concepts that have been introduced in them. The discussion presented in this paper includes multidisciplinary approaches, such as techniques for estimation and the evaluation of injuries in human-robot collisions, mechanical and software devices designed to minimize the consequences of human-robot impact, impact detection systems, and strategies to prevent collisions or minimize their consequences when they occur.

Energy reserve, estimated as body condition score (BCS), is the major determinant of the re-initiation of ovarian activity in postpartum cows. Leptin, IGF-I and insulin are positively related to BCS and are putative mediators between BCS and reproductive function. However, when BCS and body composition dissociates, concentrations of these metabolic hormones are altered. We hypothesized that increasing lean muscle tissue, but not fat tissue, would diminish the reproductive response to oestrus induction treatments. Thirty lactating beef cows with BCS of 3.10±1.21 and 75.94±12 days postpartum were divided in two groups. Control cows (n=15) were supplemented with 10.20 kg of concentrate daily for 60 days. Treated cows (n=15) were supplemented equally, and received a β-adrenergic receptor agonist (β-AA; 0.15 mg/kg BW) to achieve accretion of lean tissue mass and not fat tissue mass. Twelve days after ending concentrate supplementation/β-AA treatment, cows received a progestin implant to induce oestrus. Cows displaying oestrus were inseminated during the following 60 days, and maintained with a fertile bull for a further 21 days. Cows in both groups gained weight during the supplementation period (Daily weight gain: Control=0.75 kg v. β-AA=0.89 kg). Cows treated with β-AA had a larger increase in BCS (i.e. change in BCS: control=1 point (score 4.13) v. β-AA=2 points (score 5.06; P0.05) did not differ between groups. However, the number of cows displaying oestrus (control 13/15 v. β-AA 8/15; P

In years to come, water and energy are two issues of concern for trying to keep a continued and sustainable existence of mankind on earth. Regarding the generation and reliable supply of energy; it is a vital matter, especially for those marginal and inaccessible rural communities, which continually struggle for energy as constantly it is in short supply and their only energy sources at hand are crops and forest biomass. When there is abundant availability of vegetative biomass and crop residues, consequently processing them for biogas generation is a great opportunity for energy diversification which will allow for having a sustainable and readily access to other available energy sources. The objective of this work was to undertake a conceptual engineering design for a portable biodigester by using sheep manure, whereas its performance is modeled for evaluating its descentral operation, especially when it has to handle a previously treated high dry matter substrate. Simultaneously, it has to reduce as much as possible the energy utilized for transporting the residues and the biofertilizer cake, by carefully planning the location for feedstock loading and biofertilizer unloading sites. The biodigester consists of a cylinder with an effective operating capacity of 10 m3, where a substrate with 39% of total solids is poured, having a retention time of 30 days, and bearing in mind that it should operate within the thermophilic range which is controlled by the container thermal insulation and warm water heated by solar energy. During the simulation performance trials for the biodigester running with residues to generate biogas, the energy balance for the descentral scheme was more efficient as it got an energy saving of 50% when it was compared to a centralized functioning mode.

L’agro-écologie utilise les processus naturels et les ressources locales plutôt que des intrants chimiques pour assurer la production tout en limitant l’impact environnemental de l’agriculture. A cette fin, des innovations en génétique sont nécessaires pour disposer d’animaux productifs et adaptés à des contextes locaux variés. Pour toute filière d’élevage, réorienter les programmes de sélection actuels semble plus utile que développer des programmes spécifiques qui peineront à être efficaces en termes de coûts et de progrès génétiques attendus. Améliorer la robustesse des animaux vise à promouvoir leurs capacités d’adaptation en intégrant de nombreux critères de sélection, en particulier de reproduction, santé, et d’adaptation à des ressources alimentaires peu digestibles et au changement climatique. Cela amène à considérer les interactions génotype-environnement dans la prédiction des valeurs génétiques et à évaluer les performances des animaux dans des systèmes à bas intrants pour sélectionner ceux qui sont adaptés à des conditions limitantes. La standardisation tant des animaux que des conditions d’élevage paraît antinomique avec les principes de l’agro-écologie prônant une adaptation des animaux aux ressources et contraintes locales dans des systèmes peu artificialisés et très liés à leur environnement physique. Il n’y a donc pas UN animal type agro-écologique, mais DES animaux aux profils variés permettant de répondre aux attentes de l’agro-écologie. Face à la diversité des milieux et des systèmes d’élevage, il faut conserver une diversité génétique importante intra-race, mais aussi préserver la diversité génétique entre races. Cela nécessite une caractérisation phénotypique et génétique des races locales. Enfin, il s’agit de favoriser l'appropriation par les éleveurs et les techniciens d’élevage des outils et des ressources génétiques disponibles pour répondre à leurs besoins.

Los cirujanos plásticos nos enfrentamos cada vez con más frecuencia en nuestra consulta a pacientes que desean o necesitan retirar sus implantes mamarios. Algunas de estas pacientes rechazan la idea de un reemplazo protésico, pero son exigentes con el resultado cosmético postoperatorio. Describimos la técnica empleada en 68 casos consecutivos y los resultados que hemos obtenido al tratar las secuelas en la mama tras la retirada de los implantes, fundamentalmente una disminución de volumen asociada a ptosis y excedente cutáneo. Esta técnica se basa en la extracción de los implantes y correccion mamaria simultanea con colgajo dermoglandular inferior que denominamos "autoprotesis" asociado a injerto graso simultáneo. Los resultados logran mejorar la forma, proyección y conificacion de la mama tras la retirada de los implantes, con un alto grado de satisfacción por parte de las pacientes.

Las mamas tuberosas, denominadas así por Rees y Aston, y también llamadas hernias del complejo areolar (Bass), Snoopy deformity (Gruber), mamas tubulares (Williams), hipoplasia del polo inferior (Brink) o mamas de base estrecha (Puckett), son una malformacion en el desarrollo del volumen mamario en los cuadrantes inferiores con hernia areolar secundaria (placa areolar y músculo mamilar débiles), areola ancha y protruida (en la mitad de los casos), ascenso del surco submamario, mamas hipotróficas y raramente hipertróficas, con asimetrías en las dos terceras partes de las pacientes. Presentamos la estrategia quirúrgica adecuada para resolver esta patología utilizando solo implantes anatómicos de gel cohesivo sin necesidad de tallar colgajos glandulares. De esta manera, disminuimos la morbilidad quirúrgica, ofreciendo resultados estables y con alta satisfaccion por parte de las pacientes.

Many factors related to transport to abattoir affects meat quality, but scarce information is available in suckling lambs. Thus, the aim of this work was to evaluate the effects of season and stocking density on carcass and meat quality of suckling lambs during commercial transport to the abattoir. A factorial design (2 × 3) was used: two seasons (winter and summer) and three stocking densities (SD; 0.08, 0.12 and 0.20 m2 animal-1). Meat quality variables were measured in the M. longissimus at 24 h post-mortem and after 5 days of refrigerated storage. Lambs transported in summer showed lower liver weight (p

The rapid technological evolution, which is characterizing all the disciplines involved within the wide concept of smart cities, becomes a key factor to trigger true user-driven innovation. In this context 3D city models will play an increasingly important role in our daily lives and become an essential part of the modern city information infrastructure (Spatial Data Infrastructure). The goal of this paper is to introduce the i-SCOPE (interoperable Smart City services through an Open Platform for urban Ecosystems) project methodology and implementations together with key technologies and open standards. Based on interoperable 3D CityGML UIMs, the aim of i-Scope is to deliver an open platform on top of which it possible to develop, within different domains, various "smart city" services. Moreover, in i-SCOPE different issues, transcending the mere technological domain, are being tackled, including aspects dealing with social and environmental issues. Indeed several tasks including citizen awareness, crowd source and voluntary based data collection as well as privacy issue concerning involved people should be considered.

Une série d’expérimentations a été conduite pour mesurer l’impact de la monotraite à l’échelle de la lactation de brebis laitières de race Lacaune. La production de lait et sa composition, la physiologie et la morphologie de la mamelle, l’ingestion et le métabolisme énergétique ont été mesurés tout au long de la période de traite, du sevrage au tarissement. L’impact de la monotraite a été modélisé à l'échelle de l'exploitation et du bassin de production. La perte de lait a été de 14 % chez les multipares comme les primipares. Selon la ration offerte, le taux butyreux a diminué ou a eu tendance à augmenter, alors que le taux protéique n’a pas été modifié ou a augmenté en lien avec une augmentation des protéines solubles. Les quantités ingérées n’étaient pas différentes entre brebis en traite biquotidienne et monotraite, ce qui a entraîné un bilan énergétique positif supérieur pour ces dernières. Cela s’est traduit par des taux d’acides gras non estérifiés rapidement plus bas et de leptine supérieurs. La mamelle a été perturbée dans les premiers jours de monotraite, mais a rapidement retrouvé son intégrité du fait d’une bonne plasticité sans aucune conséquence sur sa santé. Au niveau de l’exploitation, la monotraite entraîne une perte de revenu qui peut être compensée en tout ou partie par un passage en monotraite à un stade plus tardif ou un allongement de la période de traite. Des travaux complémentaires conduits à l’échelle de l’exploitation permettraient de mieux préciser les répercussions de cette pratique à ce niveau et à celui du bassin de production.

Background. Although non-invasive ventilation (NIV) efficacy in the treatment of acute hypercapnic respiratory failure (AHRF) have been previously demonstrated, not all the studies reveal this fact in the same degree, with some variability in the results. This study aimed to analyse variables related to NIV outcome for AHRF. Methods. A group of consecutive patients requiring NIV due to AHRF were included in a prospective observational cohort study performed in conventional wards. Variables considered included those reported in the literature, as well as staff problems during the management of the ventilators. The study aimed to include all patients during one year, but after the initial results, it had to be suspended. Results. Fifteen patients were included in the study: 10 males, mean age 68 ± 12. APACHE-II score was 17.6 ± 6.5. pH and pCO2 before NIV were 7.22 ± 0.11 and 110 ± 72 mmHg respectively. pH, corticosteroids use, APACHE score, and EPAP were found to influence outcome. Besides, an inadequate use of NIV due to lack of personnel training was detected in all patients with NIV failure (RR 3.5; 95% CI: 1.08-11.2; p = 0.007). In the light of these results, the study had to be suspended and patients were transferred to the respiratory ward. Conclusions. NIV is a life-saving respiratory treatment influenced by several factors, of which staff training is a key one. Centres attending acute respiratory patients should have an area in which this requirement is fulfilled.

Se analizó la diversidad genética de dos poblaciones de borrego cimarrón, provenientes de la Isla Tiburón y del estado de Sonora (Sierra Cirios, Sierra el Viejo y Sierra el Encierro). A partir de muestras de sangre se extrajo ADN que se utilizó para amplificar un panel de seis loci microsatélites. El número de alelos promedio encontrados para los loci estudiados fue 8 para la población de la Isla y 7 para el estado Sonora. La heterocigosidad media esperada y los índices de información polimórfica (PIC) fueron muy similares en las dos poblaciones, con valores de 0.716 y 0.732, 0.66 y 0.69, para la población de Sonora y la de Isla Tiburón, respectivamente. Ambas poblaciones se encuentran en desequilibrio Hardy-Weinberg debido a un exceso de homocigotos. El análisis molecular de varianza (AMOVA) indica una baja diferenciación genética (FST = 0.059; P =0.0001). Los resultados de este trabajo muestran que es necesario establecer estrategias para monitorear y mantener la diversidad genética y pureza de la población de la Isla Tiburón. En el caso de las poblaciones del estado de Sonora es necesario monitorearlas ampliando el número de muestra a fin de evaluar su variabilidad genética y determinar el manejo reproductivo más adecuado, para el apareamiento entre ejemplares.

Many hydrological studies of forested ecosystems focus on the study of the forest canopy and have partitioned gross precipitation into throughfall and stemflow. However, the presence of forest litter can alter the quantities of water available for soil infiltration and runoff. Little information exists regarding the value of storage and drainage parameters for litter layers. Vegetation parameters of this kind are required in physically-based and lumped conceptual models to quatify the availabilty and distribution of water. Using a rainfall simulator and laboratory conditions two main objectives were investigated using layers of recently seneced poplar leaves, fresh grass or woodchips: 1) Effect of rain intensity on storage. With this respect we found that: maximum storage (Cmax), defined as the detention of water immediately before rainfall cessation, increased with rainfall intensity. The magnitude of the increment was up to 0.5 mm kg−1 m−2 between the lowest (9.8 mm h−1) and highest (70.9 mm h−1) rainfall intensities for poplar leaves. Minimum storage (Cmin), defined as the detention of water after drainage ceased, was not influenced by rainfall intensity. Repeated wetting-draining cycles or layer thickness have no effect on Cmax or Cmin. 2) The evaluation of drainage coefficient for the Rutter model. This model was found accurate to predict storage and drainage in the case of poplar leaves, was less accurate for fresh grass and resulted in overestimations for woodchips. Additionally, the effect of an underlaying soil matrix on lateral movement of water and storage of poplar leaves was studied. Results indicated that the soil matrix have no effect on Cmax or Cmin of the litter layer. Lateral movement of water in the poplar layer was observed at intermediate rainfall intensities (30.2 and 40.4 mm h−1), but not a the lowest or highest rates.

The COVID-19 pandemic forced university and college counseling and psychological service centers to swiftly switch to telepsychology service delivery to meet the continuing needs of student clients. This study was conducted at the onset and peak periods of the COVID-19 outbreak. We explored student client and counselor acceptability, attitudes, perceptions, experiences, barriers, and facilitators to remote telepsychology services using Qualtrics survey methodologies. Student clients and counselors were sent, via e-mail, two separate, but parallel anonymous questionnaires developed for purposes of this study. Results revealed that most student clients agreed that mental health service delivery via telepsychology was an adequate alternative to face-to-face therapy, there were few challenges with telepsychology with ease of access a key benefit. Student clients also felt that the therapeutic alliance was commensurate with face-to-face therapy while identifying lack of privacy in the home as the most problematic aspect of telepsychology. Counselors and student clients both identified convenience as the most important characteristic of telepsychology. Limitations are discussed as well as directions for future research.

The MUREX (monitoring the usable soil reservoir experimentally) experiment was designed to provide continuous time series of field data over a long period, in order to improve and validate the Soil-vegetation-Atmosphere Transfer (SVAT) parameterisations employed in meteorological models. Intensive measurements were performed for more than three years over fallow farmland in southwestern France. To capture the main processes controlling land-atmosphere exchanges, the local climate was fully characterised, and surface water and energy fluxes, vegetation biomass, soil moisture profiles, surface soil moisture and surface and soil temperature were monitored. Additional physiological measurements were carried out during selected periods to describe the biological control of the fluxes. The MUREX data of 1995, 1996, and 1997 are presented. Four SVAT models are applied to the annual cycle of 1995. In general, they succeed in simulating the main features of the fallow functioning, although some shortcomings are revealed.Key words. Hydrology (evapotranspiration; soil moisture; water-energy interactions).

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A 33-year-old woman sought medical attention for a painful swelling of the left ankle. Plain radiographs revealed an osteolytic lesion involving the left distal tibia. An excisional biopsy provided the diagnosis of leiomyosarcoma in the tibia. A staging work-up was performed and an abdominal CT showed 4 liver hypodense lesions in both lobes with peripheral contrast enhancement. A liver biopsy confirmed the diagnosis of epithelioid hemangioendothelioma of the liver. No association between these two entities has been described before. This case introduces the importance of the pathological confirmation of apparent metastatic lesions in low grade sarcomas and provides a review of the literature of both tumours.

Se presentan algunos resultados preliminares del análisis isotópico de carbono en carbonatos de ganga de diferentes tipos de yacimientos, así como en rocas metamórficas. Las muestras analizadas provienen de: el deposito paleokárstico de La Purísima en Coahuila, el yacimiento epitermal de metales preciosos de El Barqueno en Jalisco, la breccia de cobre de La Sorpresa en Jalisco, el yacimiento de skarn de Pb-Zn-W de Zimapán en Hidalgo, el yacimiento de pórfido de cobre de La Verde en Michoacán y rocas metamórficas de alto grado de Oaxaca. La composición isotópica de δ13C de estos carbonatos varía dentro de los intervalos esperados (i.e. -10 a 0 por millar) para cada tipo de yacimiento y roca metamórfica.

Se demuestra la existencia de provincias o franjas metálicas en la porción centro-occidental de Mé:xico cuya distribución y origen obedecen a los procesos tectónicos siguientes: l. Formación de un arco volcánico submarino con alto contenido de pelíticos en la zona de post-arco, La mineralización es sinsedimentaria de cobre-pirrotita en el arco y polimetálica en el post-arco. Estas rocas están afectadas por un metamorfismo epizonal de la facies de esquistos verdes. Se propone el nombre de "Secuencia Volcanosedimentaria Metamorfizada" para estas rocas cuya edad es Permo-Triásica. 2. Magmatismo intrusivo calcoalcalino de margen continental y edad Jurásica que forma el batolito de Puerto Vallarta y algunas rocas intrusivás de Baja California. No se conocen mineralizaciones asociadas a estas rocas. 3. Levantamiento, erosión y formación de deltas progradantes y desarrollo de yacimientos de origen químico asociados a sedimentos terrígenos con mineralizaciones de Pb, Zn, Ag. 4. Formación de un arco de islas con cuenca marginal, creada a partir de una tectónica distensiva en la zona de post-arco. La edad del arco es Cretácico Temprano. Este marco geol6gico contiene los sulfuros masivos polimetálicos más importantes de México. Se propone el nombre de "Secuencia Volcanosedimentaria no Metamórfica" para este conjunto litológico. 5.Migraciones laterales del magmatismo continental ocurridas entre el Cretácico Tardío y el Terciario Medio, quedando definidas las provincias metálicas del centro-occidente de México. Las asociaciones más importantes son: Fe (Ti,Cu,Sn); Cu,Au; Pb,Zn,Ag(Au,Cu); Au,Ag(Pb,Zn,Cu); Sn; CaF2: Mn y Hg,Sb(Mn). La distribución de estas franjas es semiparalela a la actual línea de costa y en varias de ellas se observan traslapes debidos a procesos heterocronos. 6. En el Reciente se están desarrollando. depósitos de placer en litorales y plataforma continental con mineralización de magnetita, hematita, rutilo y zircón. doi: https://doi.org/10.22201/igeof.00167169p.1988.27.4.810

Se reportan resultados paleomagnéticos para las formaciones jurásicas Yucuñuti y Caliza con Cidaris. Las regiones estudiadas de Tezoatlán y Tlaxiaco, Estado de Oaxaca, se encuentran en la entidad geológica denominada Terreno Mixteca, para la cual se han sugerido relaciones tectónicas y estratigráficas que hacen suponer la ocurrencia de movimientos durante su historia tectónica y paleogeográfica. Durante el Jurásico se desarrolló en la región un proceso de hundimiento asociado a un régimen tectónico tensional. Este proceso lo manifiesta una gruesa secuencia fluvial y palustre que varía a marina. La polaridad de la sedimentación para el Jurásico y la afmidad paleobiogeográfica de sus amonitas indican una conexión con el Pacífico. El registro paleomagnético para estas formaciones presenta direcciones medias, interpretadas como Jurásicas de acuerdo con las pruebas de laboratorio y de campo, que difieren de las direcciones esperadas con respecto al cratón de Norteamérica. La dirección media para la Formación Yucuñuti es de N= 32, Dec= 328.6°, lnc= 34.8°, k= 66 and 95 = 15°. La dirección media para la Formación Caliza con Cidaris es de N = 92, Dec = 12.8°, Inc. = 38.1 °, k= 83 and 95=7°. Las diferencias en la inclinación reflejan traslaciones del Terreno Mixteca (y Oaxaca) a partir de una posición más septentrional en el Pacífico, mientras que las diferencias en declinación indican rotaciones entre 18° y 30° en el sentido contrario a las manecillas del reloj. Estos movimientos deben haber ocurrido entre el Oxfordiano y el Albiano. doi: https://doi.org/10.22201/igeof.00167169p.1988.27.4.808