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We review how the international modelling community, encompassing integrated assessment models, global and regional Earth system and climate models, and impact models, has worked together over the past few decades to advance understanding of Earth system change and its impacts on society and the environment and thereby support international climate policy. We go on to recommend a number of priority research areas for the coming decade, a timescale that encompasses a number of newly starting international modelling activities, as well as the IPCC Seventh Assessment Report (AR7) and the second UNFCCC Global Stocktake. Progress in these priority areas will significantly advance our understanding of Earth system change and its impacts, increasing the quality and utility of science support to climate policy. We emphasize the need for continued improvement in our understanding of, and ability to simulate, the coupled Earth system and the impacts of Earth system change. There is an urgent need to investigate plausible pathways and emission scenarios that realize the Paris climate targets – for example, pathways that overshoot 1.5 or 2 °C global warming, before returning to these levels at some later date. Earth system models need to be capable of thoroughly assessing such warming overshoots – in particular, the efficacy of mitigation measures, such as negative CO2 emissions, in reducing atmospheric CO2 and driving global cooling. An improved assessment of the long-term consequences of stabilizing climate at 1.5 or 2 °C above pre-industrial temperatures is also required. We recommend Earth system models run overshoot scenarios in CO2-emission mode to more fully represent coupled climate–carbon-cycle feedbacks and, wherever possible, interactively simulate other key Earth system phenomena at risk of rapid change during overshoot. Regional downscaling and impact models should use forcing data from these simulations, so impact and regional climate projections cover a more complete range of potential responses to a warming overshoot. An accurate simulation of the observed, historical record remains a fundamental requirement of models, as does accurate simulation of key metrics, such as the effective climate sensitivity and the transient climate response to cumulative carbon emissions. For adaptation, a key demand is improved guidance on potential changes in climate extremes and the modes of variability these extremes develop within. Such improvements will most likely be realized through a combination of increased model resolution, improvement of key model parameterizations, and enhanced representation of important Earth system processes, combined with targeted use of new artificial intelligence (AI) and machine learning (ML) techniques. We propose a deeper collaboration across such efforts over the coming decade. With respect to sampling future uncertainty, increased collaboration between approaches that emphasize large model ensembles and those focussed on statistical emulation is required. We recommend an increased focus on high-impact–low-likelihood (HILL) outcomes – in particular, the risk and consequences of exceeding critical tipping points during a warming overshoot and the potential impacts arising from this. For a comprehensive assessment of the impacts of Earth system change, including impacts arising directly as a result of climate mitigation actions, it is important that spatially detailed, disaggregated information used to generate future scenarios in integrated assessment models be available for use in impact models. Conversely, there is a need to develop methods that enable potential societal responses to projected Earth system change to be incorporated into scenario development. The new models, simulations, data, and scientific advances proposed in this article will not be possible without long-term development and maintenance of a robust, globally connected infrastructure ecosystem. This system must be easily accessible and useable by modelling communities across the world, allowing the global research community to be fully engaged in developing and delivering new scientific knowledge to support international climate policy.

Abstract Gas extraction from the Groningen gas field resulted in significant induced seismicity. We analyze the magnitude‐frequency distribution of these earthquakes in space, time and in view of stress changes calculated based on gas production and reservoir properties. Previous studies suggested variations related to reservoir geometry and stress. While we confirm the spatial variations, we do not detect a clear sensitivity of b‐value to Coulomb stress changes. However, we find that b‐value correlates positively with the rate of Coulomb stress changes. This correlation is statistically significant and robust to uncertainties related to stress change calculation. This study thus points to a possible influence of stress change rate on the probability of the magnitude of induced earthquakes.

When working with Earth system models, a considerable challenge that arises is the need to establish the set of parameter values that ensure the optimal model performance in terms of how they reflect real-world observed data. Given that each additional parameter under investigation increases the dimensional space of the problem by one, simple brute-force sensitivity tests can quickly become too computationally strenuous. In addition, the complexity of the model and interactions between parameters mean that testing them on an individual basis has the potential to miss key information. In this work, we address these challenges by developing a biased random key genetic algorithm (BRKGA) able to estimate model parameters. This method is tested using the one-dimensional configuration of PISCES-v2_RC, the biogeochemical component of NEMO4 v4.0.1 (Nucleus for European Modelling of the Ocean version 4), a global ocean model. A test case of particulate organic carbon (POC) in the North Atlantic down to 1000 m depth is examined, using observed data obtained from autonomous biogeochemical Argo floats. In this case, two sets of tests are run, namely one where each of the model outputs are compared to the model outputs with default settings and another where they are compared with three sets of observed data from their respective regions, which is followed by a cross-reference of the results. The results of these analyses provide evidence that this approach is robust and consistent and also that it provides an indication of the sensitivity of parameters on variables of interest. Given the deviation in the optimal set of parameters from the default, further analyses using observed data in other locations are recommended to establish the validity of the results obtained.

A flexible treatment for gas- and aerosol-phase chemical processes has been developed for models of diverse scale, from box models up to global models. At the core of this novel framework is an “abstracted aerosol representation” that allows a given chemical mechanism to be solved in atmospheric models with different aerosol representations (e.g., sectional, modal, or particle-resolved). This is accomplished by treating aerosols as a collection of condensed phases that are implemented according to the aerosol representation of the host model. The framework also allows multiple chemical processes (e.g., gas- and aerosol-phase chemical reactions, emissions, deposition, photolysis, and mass transfer) to be solved simultaneously as a single system. The flexibility of the model is achieved by (1) using an object-oriented design that facilitates extensibility to new types of chemical processes and to new ways of representing aerosol systems, (2) runtime model configuration using JSON input files that permits making changes to any part of the chemical mechanism without recompiling the model (this widely used, human-readable format allows entire gas- and aerosol-phase chemical mechanisms to be described with as much complexity as necessary), and (3) automated comprehensive testing that ensures stability of the code as new functionality is introduced. Together, these design choices enable users to build a customized multiphase mechanism without having to handle preprocessors, solvers, or compilers. Removing these hurdles makes this type of modeling accessible to a much wider community, including modelers, experimentalists, and educators. This new treatment compiles as a stand-alone library and has been deployed in the particle-resolved PartMC model and in the Multiscale Online AtmospheRe CHemistry (MONARCH) chemical weather prediction system for use at regional and global scales. Results from the initial deployment to box models of different complexity and MONARCH will be discussed, along with future extension to more complex gas–aerosol systems and the integration of GPU-based solvers.

The Earth system model EC-Earth3 for contributions to CMIP6 is documented here, with its flexible coupling framework, major model configurations, a methodology for ensuring the simulations are comparable across different high-performance computing (HPC) systems, and with the physical performance of base configurations over the historical period. The variety of possible configurations and sub-models reflects the broad interests in the EC-Earth community. EC-Earth3 key performance metrics demonstrate physical behavior and biases well within the frame known from recent CMIP models. With improved physical and dynamic features, new Earth system model (ESM) components, community tools, and largely improved physical performance compared to the CMIP5 version, EC-Earth3 represents a clear step forward for the only European community ESM. We demonstrate here that EC-Earth3 is suited for a range of tasks in CMIP6 and beyond.

This study investigates college students' current food safety knowledge and food-handling perceptions and utilized an online survey which designed based on previous studies as method. The questionnaire measured respondents' food safety knowledge and perception, and were divided into knowledge, attitudes and perception categories. The results show that college students significantly lacked in basic food safety knowledge as well as food handling skills and implies a high need to develop enhanced food safety resources for college students, especially on topics related to cross-contamination prevention, correct food preparation procedures, time and temperature control, and awareness of pathogens that cause foodborne illness.

Electrode functional layers for solid oxide cells require a combination of high reactivity and thermal stability. Here, the authors present a self-assembled vertically aligned nanocomposites of lanthanum strontium manganite and doped ceria as functional layers for high temperature applications.

A new global high-resolution coupled climate model, EC-Earth3P-HR has been developed by the EC-Earth consortium, with a resolution of approximately 40 km for the atmosphere and 0.25∘ for the ocean, alongside with a standard-resolution version of the model, EC-Earth3P (80 km atmosphere, 1.0∘ ocean). The model forcing and simulations follow the High Resolution Model Intercomparison Project (HighResMIP) protocol. According to this protocol, all simulations are made with both high and standard resolutions. The model has been optimized with respect to scalability, performance, data storage and post-processing. In accordance with the HighResMIP protocol, no specific tuning for the high-resolution version has been applied. Increasing horizontal resolution does not result in a general reduction of biases and overall improvement of the variability, and deteriorating impacts can be detected for specific regions and phenomena such as some Euro-Atlantic weather regimes, whereas others such as the El Niño–Southern Oscillation show a clear improvement in their spatial structure. The omission of specific tuning might be responsible for this. The shortness of the spin-up, as prescribed by the HighResMIP protocol, prevented the model from reaching equilibrium. The trend in the control and historical simulations, however, appeared to be similar, resulting in a warming trend, obtained by subtracting the control from the historical simulation, close to the observational one.

Most Earth system models (ESMs) are running under different high-performance computing (HPC) environments. This has several advantages, from allowing different groups to work with the same tool in parallel to leveraging the burden of ensemble climate simulations, but it also offers alternative solutions in the case of shutdown (expected or not) of any of the environments. However, for obvious scientific reasons, it is critical to ensure that ESMs provide identical results under changes in computing environment. While strict bit-for-bit reproducibility is not always guaranteed with ESMs, it is desirable that results obtained under one computing environment are at least statistically indistinguishable from those obtained under another environment, which we term a “replicability” condition following the metrology nomenclature. Here, we develop a protocol to assess the replicability of the EC-Earth ESM. Using two versions of EC-Earth, we present one case of non-replicability and one case of replicability. The non-replicable case occurs with the older version of the model and likely finds its origin in the treatment of river runoff along Antarctic coasts. By contrast, the more recent version of the model provides replicable results. The methodology presented here has been adopted as a standard test by the EC-Earth consortium (27 institutions in Europe) to evaluate the replicability of any new model version across platforms, including for CMIP6 experiments. To a larger extent, it can be used to assess whether other ESMs can safely be ported from one HPC environment to another for studying climate-related questions. Our results and experience with this work suggest that the default assumption should be that ESMs are not replicable under changes in the HPC environment, until proven otherwise.

de Siguas, Arequipa Province, Peru. The concentrations used were 2, 4, and 6 kg ha−1 with 4 applications by means of impregnation to the transplant and via drench every 15 days. The statistical design was through a DBCA with factorial arrangement randomly distributed in four blocks. The tests used were the orthogonal contrast test and Duncan’s multiple comparison test (α = 0.05). The findings showed that the treatment concentrations of 4 kg ha−1 and 6 kg ha−1 resulted in a lower incidence of Fusarium oxysporum, at 6.71% and 9.36%, an ABCPE of 637.78 and 950.14 units, and an exportable yield of 66.34 t ha−1 and 65.42 t ha−1, respectively, displaying significant differences from the control. The first application was statistically significant to the treatments with the highest number of applications, showing a greater exportable yield of 67.54 t ha−1. The best interactions between concentrations and applications were 6 kg ha−1 with 1 application, 4 kg ha−1 with 2 applications, and 4 kg ha−1 with 1 application, with exportable yields of 70.66, 69.61, and 69.11 t ha−1, respectively.

ZnO nanoparticles (NPs) were extracted from a commercial paste in both colloidal and precipitate forms. The Zetasizer analysis performed on the colloid showed ZnO NPs ranging from ∼30 nm to ∼100 nm. Thin films of ZnO were deposited on glass substrates by spin-coating technique from a mixture of the extracted colloid and precipitate. The scanning electron microscope (SEM) images showed uniformly arranged, mesoporous, and nanostructured ZnO particles of different shapes, with an estimated film thickness of 0.67 μm. Analysis by energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis (XRD) confirmed the presence of ZnO in the films, with no impurities or remnants of other materials. The XRD analysis showed a polycrystalline nature of the films and identified a pure phase formation of the hexagonal wurtzite structure. The average crystallite size calculated from the diffraction peaks is ∼43.25 nm. The calculated crystal tensile strain is 1.954 × 10−3, which increases the crystal volume by 0.728% compared with the crystal volume of standard ZnO. The calculated crystal parameters are a = b = 3.258 Å and c = 5.217 Å. The calculated dislocation density (d) and bond length Zn–O (L) are 5.35 × 10−4 nm−2 and 2.695 Å, respectively. Ultraviolet-visible absorption spectra showed an optical band gap of ∼3.80 eV.

Understanding the physics of fault lubrication during earthquake propagation can help assess seismic hazard. In this study, by replicating earthquakes in the laboratory at upper-crustal conditions, the authors show that fluid thermodynamics control fault lubrication, specifically at man-made earthquake depths.

Abstract Recently, projects have been proposed to engineer deep geothermal reservoirs in the ductile crust. To examine their feasibility, we performed high-temperature (up to 1000 °C), high-pressure (130 MPa) triaxial experiments on granite (initially-intact and shock-cooled samples) in which we measured the evolution of porosity during deformation. Mechanical data and post-mortem microstuctural characterisation (X-ray computed tomography and scanning electron microscopy) indicate that (1) the failure mode was brittle up to 900 °C (shear fracture formation) but ductile at 1000 °C (no strain localisation); (2) only deformation up to 800 °C was dilatant; (3) deformation at 900 °C was brittle but associated with net compaction due to an increase in the efficiency of crystal plastic processes; (4) ductile deformation at 1000 °C was compactant; (5) thermally-shocking the granite did not influence strength or failure mode. Our data show that, while brittle behaviour increases porosity, porosity loss is associated with both ductile behaviour and transitional behaviour as the failure mode evolves from brittle to ductile. Extrapolating our data to geological strain rates suggests that the brittle-ductile transition occurs at a temperature of 400 ± 100 °C, and is associated with the limit of fluid circulation in the deep continental crust.

The case delves into the historical and cultural roots of African education, emphasizing the vital role of elders and community in the learning process. It examines the impact of African educational philosophies, particularly from the Nile and Niger river valleys, on the development of character, humanness, and spirituality. The case explores the adaptation of these philosophies by African people during the Middle Passage and their application in Western contexts for the supervision of African American teachers. By interweaving culture, history, education, and storytelling, the authors aim to highlight the unique contributions of African American educational experiences. They argue that these experiences provide valuable strategies for the liberation struggle and the transformation of Black teacher development. The case also explores contemporary issues in the teaching profession, such as the limited presence of African American educators, pedagogical negligence, and professional marginalization, proposing culturally-centered tools for community preservation and well-being. The central theme is the importance of relational supervision rooted in African and African American cultural knowledge, which is seen as key to nurturing Black novice teachers and fostering their professional development.

Colombia is a country with national policies, in order to manage, direct and guide necessary actions to treat solid waste and reduce the negative environmental impacts that these generated after their disposition. These policies are consistent with international guidelines, and it is from them that efforts are made to reduce world consumption of primary energy, thus generating interest in the potential use of biomass as a source alternative energy. The biochemical methane potential (BMP) is a test used to characterize the raw materials in trials related to the optimization of anaerobic digestion and co-digestion; it allows to find the type of substrate and co-substrate with the greatest methane potential production. This study focuses on the evaluation of the production of methane through the anaerobic process of digestion and co-digestion using three different available substrates in Colombia, of which there is very few information on the methane production potential (cocoa shell and pods), along with other common waste (organic fraction of municipal solid waste and pig manure). This evaluation was realized applying the BMP test to each individual substrate and six mixtures of these substrates; anaerobic processes of digestion and co-digestion were carried out, by testing with batch reactors of 250 mL, in mesophilic conditions (32°C - 36°C), obtaining the BMP of each substrate and of the mixtures. To these residues, a physical-chemical characterization was realized prior the BMP test, which was determined: values of solid volatile, total solids, organic matter and nitrogen Kjeldahl. With the obtained characterization six mixtures were prepared to evaluate: three with carbon/nitrogen (C/N) relation of 25 and three with C/N relation equal to 35. Methanation potential was also evaluated in three levels of volatile solids grams (gVs): 0.5, 1 and 2. The three residues evaluated (pig manure, cocoa shell and pods, and organic fraction of municipal solid waste) have the ability to be used for the production of methane. In the trial of BMP, the pig manure was the higher methane production with 437.33 mL CH4/gVs, followed by organic fraction of municipal solid waste with a generation of 377.25 mL CH4/gVs. The test results of anaerobic co- digestion indicate that the best mix in terms of biogas production is the Mixture1, with 25 C/N relation and 0.5 gVs, which allows inferring optimal condition at the start of the experiment. This mixture reports a production of methane 2,485.91 mL CH4/gVs. The results obtained in the different tests allow visualizing that the application of this methodology serves as a valuation of the solid residues that cause a negative impact on the environment.

Algunos herbicidas según su estructura y características fisicoquímicas persisten en el ambiente y es de gran importancia conocer con certeza el tiempo en el cual la molécula química persiste adherida a las partículas del suelo, para determinar el momento oportuno en el cual es posible establecer el siguiente cultivo sin que haya problemas de fitotoxicidad propiciando por la acumulación de residuos en agua y suelo principalmente subiendo después por la cadena trófica y llegando hasta los seres humanos por consumo de alimentos, principalmente hortalizas de pocos días de desarrollo. La presente investigación determinó el efecto residual del herbicida Integrity, así como el efecto del fungicida Headline como promotor del efecto Agcelence para la remisión de síntomas de fitotoxicidad en la rotación de maíz con hortalizas, en donde los resultados fueron los siguientes: Integrity no ocasionó síntomas de fitotoxicidad a la dosis comercial (1.5 L.ha-1) aplicado en post-emergencia al cultivo, sin embargo las plantas de maíz presentaron una menor altura, se observó efecto residual hasta los 75 dias después de la aplicación en el testigo sin Headline tanto en chile, calabaza y jitomate; se encontró que Headline (pyraclostrobin) en su dosis alta (2.5 mL.L-1) ayuda en la remisión de los síntomas de fitotoxicidad ocasionados por el herbicida Integrity en un nivel agronómicamente aceptable (< 12.5 % de fitotoxicidad) en jitomate y calabaza.

En México el banano es el segundo frutal de mayor importancia económica, con una producción de 2.2 millones de toneladas anuales; los nematodos son las plagas más importantes del banano afectando el crecimiento y desarrollo debido al daño ocasionado en raíces y rizoma, los más reportados han sido: Radopholus similis (nematodo barrenador), Helicotylenchus multicinctus (nematodo del espiral) y Meloidogyne spp. (nematodo agallador). El principal método de control se ha basado en productos químicos con resultados muy variados. En este estudio se evaluaron la eficacia biológica de nematicidas organofosforados y carbamatos para el control de estas tres especies mediante las variables densidad de nematodos en suelo cercano a raíz y en raíz, porcentaje de daño causado (severidad), peso de raíces muertas, peso de raíces sanas y vigor de hijuelos mediante el diámetro basal, altura y número de hojas. De acuerdo con los resultados obtenidos, el producto organoclorado (Terbufos) tuvo una eficacia por debajo del 80% a diferencia del carbamato (Oxamil) Oaxamil que en sus dosis de 2.7 ml/hijo mostró tener mayor eficacia en las especies de Radhopolus similis y Pratylenchus sp. en raíz, en tanto que para el control de Meloidogyne sp. fue mejor la dosis de 2.4 ml/hijo. Para el control de nematodos en suelo cerca de la raíz Oaxamil en dosis de 2.4 ml/hijo obtuvo mejor resultado para el control de Radhopolus similis y Meloidogyne sp. en tanto que para el control de Pratylenchus sp. fue mejor en su dosis de 2.7 ml/hijo.

El jitomate y la zanahoria son dos hortalizas muy susceptibles a nematodos agalladores como Meloidogyne spp. En zanahoria ocasionan serias reducciones en los rendimientos y pueden incluso llegar a la pérdida total del cultivo, cuando se presenta en zanahoria hay una deformación de las raíces adventicias y por tanto una deformación en la raíz principal, esto hace que se pierda la presentación y calidad de fruto. En tomate el comportamiento es similar, con la formación de agallas en las raíces impidiendo una buen absorción de agua y nutrientes. En este experimento se evaluaron dos productos del grupo químico de los carbamatos, más utilizados para el control de nematodo agallador para visualizar posibles efectos de resistencia a este grupo químico. Los resultados en zanahoria muestran que carbofuran en dosis de 2500 g. ha-1 es quien mejor eficacia tiene para el control de Meloidogyne, mientras que la dosis baja es la que menos control tiene. En el caso del tomate el Oaxamil en su dosis de 4.7 L.ha-1 es la que mejor controla la población de nematodos agalladores y por lo tanto aumenta el rendimiento en la producción.

En América Latina existe poca información acerca de los motivos frecuentes de consulta médica y eutanasia en perros, así como de las implicaciones de los problemas de com - portamiento. e specialmente en Uruguay no hay información al respecto. e l objetivo de este estudio fue conocer las causas más frecuentes de consulta médica y eutanasia de los perros en la ciudad de Montevideo a través de una encuesta a los médicos veterinarios, y la implicancia de los problemas de comportamiento. s e realizó una encuesta a una muestra aleatoria (n = 100) de médicos veterinarios de clínicas de Montevideo. Las causas más frecuentes de consulta médica por dueños de perros son las afecciones de la piel, seguido de afecciones digestivas y respiratorias, y menos frecuentemente las infecciones, los accidentes y los neoplasias (p < 0,0001). Los problemas de conducta ocupan solo el 1% de los motivos de consulta. Las razones más frecuentes para la eutanasia de perros fueron por edad (ancianos) y por neoplasias, seguidas por afecciones renales, infecciones y accidentes (p < 0,0001). s olo el 35% de los veterinarios ha llevado a cabo eutanasias en sus clínicas; entre ellas, la eutanasia por los problemas de conducta representó apenas el 2%. a unque en Uruguay se realizan eutanasias por problemas de comportamiento, las mismas se dan en un muy bajo porcentaje.

Measurements of stem respiration were conducted for a period of four years (1999-2002) in 14-year old Norway spruce (Picea abies [L.] Karst) trees exposed to ambient (CA) and elevated CO2 concentration (CE; ambient plus 350 μmol mol-1). Stem respiration measurements of six trees per treatment were carried out 2-3 times per month during the growing season. Stem respiration in CE treatment was higher (up to 16 %) than in CA treatment. Temperature response of stem respiration (Q10) for the whole experimental period ranged between 1.65-2.57 in CA treatment and 2.24-2.56 in CE treatment. The mean stem respiration rate normalized to 10 °C (R10) in CA and CE treatments ranged between 1.67-1.95 and 2.19-2.72 μmol(CO2) m-2 s-1, respectively. Seasonal variations in stem respiration were related to temperature and tree growth.

Ustilago maydis (D. C.) Corda es el hongo fitopatogénico que produce el "huitlacoche" en las mazorcas de maíz. Su producción es de marcado interés comercial; pero su rendimiento y calidad pueden verse afectados debido a la presencia antagónica de levaduras asociadas a la agalla. Dependiendo del grado de infección en estas estructuras puede existir mayor contenido de mezcla de levaduras que de U. maydis, lo que puede ser una de las causas de la baja infestación en campo. Los objetivos del trabajo fueron diagnosticar la presencia de levaduras en aislamientos integrantes de un cepario de U. maydis y en agallas frescas de huitlacoche y tratar de explicar su asociación. Para diferenciar los dos tipos de microorganismos, se empleó la prueba de ureasa y la identidad fue corroborada por técnicas moleculares y secuenciación de ITS de las levaduras. Los resultados indicaron que éstas pertenecen a las especies Candida railenensis, C. quercitrusa y Pichia guilliermondii y fueron capaces de inhibir el crecimiento de U. maydis en condiciones de laboratorio.

El zinc y acero galvanizado (hot dip) se utilizan frecuentemente como materiales de construcción. El zinc tiene relativamente buena resistencia en la atmósfera debido a su oxidación en el aire, formando una capa protectora. Sin embargo, algunos productos de corrosión de zinc pueden ser disueltos por las lluvias y agua condensada sobre la superficie del metal. Este proceso es conocido como runoff del metal. Con el objetivo de estimar el proceso de runoff de zinc desde sus primeras etapas en clima tropical húmedo, muestras de zinc puro y acero galvanizado han sido expuestas en atmósfera abierta (rural y urbana) durante 2 años. Los resultados revelan altos valores de runoff de zinc (8,20–12,40 ±0,30 g/m2año), siendo este, hasta 80 % de la masa total perdida por corrosión del zinc. El proceso runoff y de corrosión es más acelerado en el zinc, que en el acero galvanizado. Se discuten los principales factores que controlan el proceso runoff.

The measurements of soil CO2 efflux in a Norway spruce (Picea abies [L.] Karst.) forest stand are reported for a 6-month period (from May 1st to October 26th 1999). Forest floor CO2 efflux was measured at four positions using a portable infra-red gas analyser (LI-COR), operating as a closed dynamic system and connected to a portable soil chamber. Soil CO2 efflux was measured 3-4 times per month. Soil temperature at a depth of 5 cm was recorded during the whole period with an interval of ten minutes. An exponential regression was used to describe the relationship between soil temperature and soil CO2 efflux. On the basis of this relationship Q10 values were calculated. The averaged value of Q10 for the studied Norway spruce forest stand was 3.74.

Tungsten trioxide (WO3) films were prepared using polystyrene spheres of two different diameters as a template in order to create porous layers. X-ray diffraction data and electron microscopy images show that annealed films exhibit polycrystalline structure with monoclinic phase and pore size of approximately hundred nanometers. The optical band gap energies have been determined by photoacoustic spectroscopy as 3.17 eV, and this value was not affected by sample morphology. Low temperature photoluminescence spectra exhibit broad band in the blue region. Deconvolutions of PL spectra show that there are two transitions which intensity depends on thin film pore size. We discuss the possible origin of this emissions associated with oxygen vacancies and surface states. A comparative study of the WO3 films used as photoanodes is presented and correlated with PL results.

Zinc oxide (ZnO) thin films were grown by nonreactive RF sputtering at room temperature under varying argon pressures (PAr). Their optical band gap was found to increase from 3.58 to 4.34 eV when the argon pressure increases from 2.67 to 10.66 Pa. After annealing at 200°C and 500°C, optical band gaps decrease considerably. The observed widening of the band gap with increasing PAr can be understood as being a consequence of the poorer crystallinity of films grown at higher pressures. Measurements of morphological and electrical properties of these films correlate well with this picture. Our main aim is to understand the effects of PAr on several physical properties of the films, and most importantly on its optical band gap.

Las poblaciones de Calidris minutilla (zarapiquito) presentan variaciones morfométricas tanto en los lugares de cría como en los de invernada. Se documentan la razón de sexos (N = 99) y medidas morfométricas (N = 49) del zarapiquito en Cuba a partir de especímenes conservados en colecciones científicas. Además, se evalúan posibles variaciones en la longitud del pico teniendo en cuenta la ubicación longitudinal (grados) y el tipo de zona costera donde fue realizado el muestreo. La proporción de hembras fue del 0,47 y las medidas morfométricas estaban dentro del rango descrito para esta especie. Las variaciones en la longitud del pico fueron atribuibles únicamente al sexo y no a las características del lugar de captura.

Folliculostellate cells (FSC) have been reported in pituitary of several mammalian species. FSC morphology and secreted sub- stances have been instrumental to the under- standing of their function. The purpose of this work was to perform an immunohistochemi- cal, morphometric and ultrastructural study of the pituitary pars distalis FSC in adult male viscacha and to analyze their relation with hormone secreting cells. Immunohistoche- mistry and image analysis were carried out in different sectors of the gland, from the middle (sector 1) to the glandular periphery (sector 5). Transmission electron microscopy with lanthanum as electrodense tracer was used. FSC formed follicles with PAS-positive colloid inside. They expressed S-100 protein mainly in both nucleus and cytoplasm. FSC were stel- late-like in shape and exhibited short cyto- plasmic processes that contacted with blood vessels and endocrine cells. In addition, some follicular colloids were immunostained with anti-S-100 protein. A few FSC were immunos- tained with anti-glial fibrillary acidic protein (GFAP) and anti-vimentin. The morphometric parameters analyzed (percentages of S-100- positive total, cellular and colloidal areas) increased from sector 1 to sector 3 and then decreased to sector 5. Hormone secreting cells, mainly lactotrophs, gonadotrophs and corticotrophs were associated with FSC and follicles. The ultrastructural study demonstrat- ed that FSC developed junctional complexes and desmosomes between their lateral mem- branes. Lanthanum freely penetrated the spaces between granulated cells and FSC, but did not penetrate into the follicular lumen. In conclusion: 1) the differential expression of S- 100 protein, GFAP and vimentin may indicate different physiological stages of FSC; 2) the expression of these proteins suggests a neuroectodermic origin of these cells; 3) FSC spa- tial distribution, association with endocrine cells, and the generation of an intercellular communication network suggest that FSC are involved in the pituitary pars distalis paracrine regulation of the viscacha.