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The focus of our study is an in-depth investigation of the quantum effects associated with the surface tension and other thermodynamic properties of nanoscopic liquid drops. The behavior of drops of quantum Lennard-Jones fluids is investigated with path-integral Monte Carlo simulations, and the test-area method is used to determine the surface tension of the spherical vapor–liquid interface. As the thermal de Broglie wavelength, λB, becomes more significant, the average density of the liquid drop decreases, with the drop becoming mechanically unstable at large wavelengths. As a consequence, the surface tension is found to decrease monotonically with λB, vanishing altogether for dominant quantum interactions. Quantum effects can be significant, leading to values that are notably lower than the classical thermodynamic limit, particularly for smaller drops. For planar interfaces (with infinite periodicity in the direction parallel to the interface), quantum effects are much less significant with the same values of λB but are, nevertheless, consequential for values representative of hydrogen or helium-4 at low temperatures corresponding to vapor–liquid coexistence. Large quantum effects are found for small drops of molecules with quantum interactions corresponding to water, ethane, methanol, and carbon dioxide, even at ambient conditions. The notable decrease in the density and tension has important consequences in reducing the Gibbs free-energy barrier of a nucleating cluster, enhancing the nucleation kinetics of liquid drops and of bubble formation. This implies that drops would form at a much greater rate than is predicted by classical nucleation theory. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the isotopic niche dynamics in resident and migratory populations of facultative amphidromous fish Galaxias maculatus (Jenyns, 1842). We hypothesised that the isotopic niche space occupied by its populations differs between resident and migratory populations and among river ecosystems. To evaluate these hypotheses, we compared the isotopic niches of G. maculatus populations along the longitudinal gradient in five river systems in the central–southern Chile. Our results revealed differences among the isotopic niches of migratory and resident populations with greater diversity of carbon sources (wider isotopic niches) in amphidromous populations and narrower isotopic niche spaces in resident populations. Galaxias maculatus is a species with complex ecological characteristics that is frequently abundant in temperate river ecosystems of the Southern Hemisphere. The dynamics of its isotopic niches and carbon sources seems to strongly relate to life-history strategy employed by specific populations and mediates trophic structure and energy flow in river ecosystems where they are abundant. [ABSTRACT FROM AUTHOR]

Context. Mock galaxy catalogues are essential for correctly interpreting current and future generations of galaxy surveys. Despite their significance in galaxy formation and cosmology, little to no work has been done to validate the predictions of these mocks for high-order clustering statistics. Aims. We compare the predicting power of the latest generation of empirical models used in the creation of mock galaxy catalogues: a 13-parameter halo occupation distribution (HOD) and an extension of the SubHalo Abundance Matching technique (SHAMe). Methos. We built GalaxyEmu-Planck, an emulator that makes precise predictions for the two-point correlation function, galaxy-galaxy lensing (restricted to distances greater than 1 h−1 Mpc in order to avoid baryonic effects), and other high-order statistics resulting from the evaluation of SHAMe and HOD models. Results. We evaluated the precision of GalaxyEmu-Planck using two galaxy samples extracted from the FLAMINGO hydrodynamical simulation that mimic the properties of DESI-BGS and BOSS galaxies, finding that the emulator reproduces all the predicted statistics precisely. The HOD shows a comparable performance when fitting galaxy clustering and galaxy-galaxy lensing. In contrast, the SHAMe model shows better predictions for higher-order statistics, especially regarding the galaxy assembly bias level. We also tested the performance of the models after removing some of their extensions, finding that we can withdraw two (out of 13) of the HOD parameters without a significant loss of performance. Conclusions. The results of this paper validate the current generation of empirical models as a way to reproduce galaxy clustering, galaxy-galaxy lensing, and other high-order statistics. The excellent performance of the SHAMe model with a small number of free parameters suggests that it is a valid method to extract cosmological constraints from galaxy clustering. [ABSTRACT FROM AUTHOR]

Background and aims: Soil properties and climate influence leaf chemical traits producing intraspecific variation in plants. Studies evaluating their importance in the South American Temperate Forest (STF) species are scarce. This study aimed to evaluate the intraspecific differences in five evergreen species of the rainforest considering two contrasting areas (i.e. temperature and precipitation), linking soil and climate with plants traits. Methods: Soil properties (Corg%, N%, C/N, δ13C, δ15N, pH and temperature), climate variables (mean annual precipitation and temperature [MAP; MAT]) and leaf chemical traits (C%, N% and P%, C/N, N/P, δ13C and δ15N) were measured and compared between two areas in the Northern Patagonia (42°- 44°S). In addition, the relationship of leaf chemical traits with soil and climate was assessed. Results: Significant differences were found in soil (Corg%, C/N and pH; p < 0.05) and climate (p < 0.05), with MAP identified as the most common factor controlling soil properties (Corg%, C/N and δ15N). Intraspecific differences in leaf chemical traits were found between areas, but not in all traits. The most common leaf chemical trait with significant differences was C%. Higher mean C% values were found in the island in plants and soils. High number of correlations (n = 13 correlations; p < 0.05) were found between leaf chemical traits. On the other hand, only MAP was a significant predictor of δ13C in the leaves. Conclusion: The leaf chemical traits variability suggests a species-specific response to the soil and climate conditions, with important influence of precipitation as the most common predictor of soil properties and δ13C in the leaves. [ABSTRACT FROM AUTHOR]

We use the TNG300 magnetohydrodynamic simulation and mock catalogues built using subhalo abundance matching (SHAM) to study the origin of the redshift evolution of the halo occupation distribution (HOD). We analyse stellar-mass selected galaxy samples with fixed number densities, spanning the redshift range 0 ≤ z ≤ 3. We measure their halo occupation functions and fit the HOD parameters to study their evolution over cosmic time. The TNG300 galaxy population strongly depends on the baryonic physics implemented in the simulation. In contrast, the galaxy population predicted by a basic SHAM model without scatter is a direct result of the cosmology of the dark matter simulation. We find that the HOD evolution is similar for both models and is consistent with a previous study of the HOD evolution in semi-analytical models. Specifically, this is the case for the ratio between the characteristic halo masses for hosting central and satellite galaxies. The only HOD parameter whose evolution varies across models is σlogM, which contains information about the stellar mass–halo mass relation of the galaxies but does not strongly impact galaxy clustering. We also demonstrate that the dependence on the specific values of the cosmological parameters is small. We conclude that the cosmology of the galaxy sample, i.e. the cosmological hierarchical growth of structure, and not the baryonic physics prescriptions, governs the evolution of the HOD for stellar mass-selected samples. These results have important implications for populating simulated light-cones with galaxies and can facilitate the interpretation of clustering data at different redshifts. [ABSTRACT FROM AUTHOR]

Several analyses have shown that Λ cold dark matter-based models cannot jointly describe the clustering (GC) and galaxy–galaxy lensing (GGL) of galaxies in the Sloan Digital Sky Survey-III (SDSS-III) Baryon Oscillation Spectroscopic Survey (BOSS), which is commonly known as the 'lensing-is-low problem'. In this work, we show that an extension of Subhalo Abundance Matching, dubbed SHAMe, successfully solves this problem. First, we show that this model accurately reproduces the GC and GGL of a mock galaxy sample in the TNG300 hydrodynamic simulation with properties analogous to those of BOSS galaxies. Then, we switch our attention to observed BOSS galaxies at z  = 0.31−0.43, and we attempt to reproduce their GC and GGL by evaluating SHAMe on two different simulations: one adopting best-fitting cosmological parameters from Planck and the other from weak gravitational lensing surveys (Low S8), where the amplitude of matter fluctuations is lower for the latter. We find excellent agreement between SHAMe predictions and observations for both cosmologies, indicating that the lensing-is-low problem originates from approximations in previous theoretical descriptions of the data. The main difference between SHAMe results in these cosmologies is the level of galaxy assembly bias, which is approximately 20 per cent and 10 per cent for Planck and Low S8, respectively. These results highlight the dangers of employing oversimplified models to analyse current large-scale structure data sets, and the need for realistic yet flexible descriptions of the galaxy–halo connection. [ABSTRACT FROM AUTHOR]

We introduce a novel technique for constraining cosmological parameters and galaxy assembly bias using non-linear redshift-space clustering of galaxies. We scale cosmological N -body simulations and insert galaxies with the SubHalo Abundance Matching extended (SHAMe) empirical model to generate over 175 000 clustering measurements spanning all relevant cosmological and SHAMe parameter values. We then build an emulator capable of reproducing the projected galaxy correlation function at the monopole, quadrupole, and hexadecapole level for separations between |$0.1\, h^{-1}\, {\rm Mpc}$| and |$25\, h^{-1}\, {\rm Mpc}$|⁠. We test this approach by using the emulator and Monte Carlo Markov Chain (MCMC) inference to jointly estimate cosmology and assembly bias parameters both for the MTNG740 hydrodynamic simulation and for a semi-analytical model (SAM) galaxy formation built on the MTNG740-DM dark matter-only simulation, obtaining unbiased results for all cosmological parameters. For instance, for MTNG740 and a galaxy number density of |$n\sim 0.01 h^{3}\, {\rm Mpc}^{-3}$|⁠ , we obtain |$\sigma _{8}=0.799^{+0.039}_{-0.044}$| and |$\Omega _\mathrm{M}h^2= 0.138^{+ 0.025}_{- 0.018}$| (which are within 0.4 and 0.2σ of the MTNG cosmology). For fixed Hubble parameter (h), the constraint becomes |$\Omega _\mathrm{M}h^2= 0.137^{+ 0.011}_{- 0.012}$|⁠. Our method performs similarly well for the SAM and for other tested sample densities. We almost always recover the true amount of galaxy assembly bias within 1σ. The best constraints are obtained when scales smaller than |$2\, h^{-1}\, {\rm Mpc}$| are included, as well as when at least the projected correlation function and the monopole are incorporated. These methods offer a powerful way to constrain cosmological parameters using galaxy surveys. [ABSTRACT FROM AUTHOR]

The spatial distribution of galaxies and their gravitational lensing signal offer complementary tests of galaxy formation physics and cosmology. However, their synergy can only be fully exploited if both probes are modelled accurately and consistently. In this paper, we demonstrate that this can be achieved using an extension of S ub- H alo A bundance M atching e xtended model (SHAMe), dubbed SHAMe. Specifically, we use mock catalogues built from the TNG300 hydrodynamical simulation to show that SHAMe can simultaneously model the multipoles of the redshift–space galaxy correlation function and galaxy–galaxy lensing, without noticeable bias within the statistical sampling uncertainties of a SDSS volume and on scales r ∈ [0.6 − 30] h −1 Mpc. Modelling the baryonic processes in galaxy–galaxy lensing with a baryonification scheme allows SHAMe's range of validity to be extended to r ∈ [0.1 − 30] h −1 Mpc. Remarkably, our model achieves this level of precision with just five free parameters beyond those describing the baryonification model. At fixed cosmology, we find that galaxy–galaxy lensing provides a general consistency test but little additional information on galaxy modelling parameters beyond that encoded in the redshift-space multipoles. It does, however, improve constraints if only the projected correlation function is available, as in surveys with only photometric redshifts. We expect SHAMe to have a higher fidelity across a wider range of scales than more traditional methods such as Halo Occupation Distribution modelling. Thus it should provide a significantly more powerful and more robust tool for analysing next-generation large-scale surveys. [ABSTRACT FROM AUTHOR]

There is evidence of constitutional rank in Chile, not only a sectoral rank, to estimate that the regulation of digital media is in an initial phase and thus insufficient to properly protect information pluralism such as political pluralism. This study aims to investigate forms of concentration, such as the communicational flow of digital media, to determine the opportunities and information defects of these media due to regulatory deficiencies in this sector. Data collection was carried out through a qualitative and quantitative methodology. The prospect of the imminent constituent process in Chile provides the opportunity to evaluate possibilities and propose changes not only at the legislative level but also at the constitutional level, which are likely to provide benefits such as freedom of expression, with greater guarantees toward the pluralism of digital media. The latter also means assessing the relevance of enshrining the right to communication in the future. [ABSTRACT FROM AUTHOR]

Cervical cancer is a significant global health issue, particularly in low- and middle-income countries. Women living with HIV (WLWH) are not only at higher risk of cervical cancer due to their increased susceptibility to high-risk human papillomavirus (HPV) infection and compromised immune status, but also higher mortality rates have been reported. Therefore, prevention, optimal screening, use of highly active antiretroviral therapy (HAART), and early access to treatment are of utmost importance in this population. While international guidelines for cervical cancer state no treatment differences should be made for WLWH, there is evidence that this population of patients represents a challenge in decision-making for medical oncologists, radiation oncologists, and surgical oncologists. This review summarizes the available evidence on the different treatment strategies for WLWH and invasive cervical cancer and highlights the need for special considerations in screening andprevention of cervical cancer in WLWH. • Women living with HIV (WLWH) and cervical have higher incidence and mortality rates. • Treatment should remain consistent with international guidelines for non-HIV individuals. • While essential, HAART poses major challenges in WLWH receiving cervical cancer treatment. • Surgery for cervical cancer is feasible, but outcomes can be altered by HIV status. • Prospective studies regarding safety and efficacy of standard of care therapies are lacking. [ABSTRACT FROM AUTHOR]

This paper presents a reconstruction of the critical theory of justice in recognition of Axel Honneth. Develops the idea of social freedom that supports his conception of justice, in confrontation with the ideas of negative and reflective freedom that feed the traditional debates of justice in contemporary political philosophy. It shows the scope and limits of the author's reflection and proposes Amartya Sen's approach to capacities as a framework for social analysis that contributes to correcting the deficiencies of the proposal for a critical theory of justice as recognition. [ABSTRACT FROM AUTHOR]

Longitudinal movement plays fundamental role in habitat colonization and population establishment of many riverine fish species. Movement patterns of amphidromous fish species at fine-scales that would allow characterizing the direction of movement and factors associated with the establishment of specific life-history strategies (resident or amphidromous) in rivers are still poorly understood. We assess fine-scale longitudinal movement variability patterns of facultative amphidromous fish species Galaxias maculatus in order to unfold its life-history variation and associated recruitment habitats. Specifically, we analyzed multi-elemental composition along core to edge transects in ear-bones (otoliths) of each fish using recursive partitions that divides the transect along signal discontinuities. Fine-scale movement assessment in five free-flowing river systems allowed us to identify movement direction and potential recruitment habitats. As such, resident recruitment of G. maculatus in freshwater (71%) and estuarine (24%) habitats was more frequent than amphidromous recruitment (5%), and was linked to availability of slow-flowing lotic or lentic habitats that produce or retain small-bodied prey consumed by their larvae. We postulate that life-history variation and successful recruitment of facultative amphidromous fish such as G. maculatus in river systems is driven by availability of suitable recruitment habitats and natural hydrologic connectivity that allows fish movement to these habitats. [ABSTRACT FROM AUTHOR]

In the hyperarid Atacama Desert, water availability plays a crucial role in allowing plant survival. Along with scant rainfall, marine advective fog frequently occurs along the coastal escarpment fueling isolated mono-specific patches of Tillandsia vegetation. In this study, we investigate the lipid biomarker composition of the bromeliad Tillandsia landbeckii (CAM plant) to assess structural adaptations at the molecular level as a response to extremely arid conditions. We analyzed long-chain n-alkanes and fatty acids in living specimens (n = 59) collected from the main Tillandsia dune ecosystems across a 350 km coastal transect. We found that the leaf wax composition was dominated by n-alkanes with concentrations (total average 160.8 ± 91.4 µg/g) up to three times higher than fatty acids (66.7 ± 40.7 µg/g), likely as an adaptation to the hyperarid environment. Significant differences were found in leaf wax distribution (Average Chain Length [ACL] and Carbon Preference Index [CPI]) in the northern zone relative to the central and southern zones. We found strong negative correlations between fatty acid CPI and n-alkane ACL with precipitation and surface evaporation pointing at fine-scale adaptations to low moisture availability along the coastal transect. Moreover, our data indicate that the predominance of n-alkanes is reflecting the function of the wax in preventing water loss from the leaves. The hyperarid conditions and good preservation potential of both n-alkanes and fatty acids make them ideal tracers to study late Holocene climate change in the Atacama Desert. [ABSTRACT FROM AUTHOR]

The large number of distributed generators, storages, and other devices which might be connected to the distribution grid pose significant modelling and control questions. It is computationally unattractive and sometimes infeasible to model and control all these devices individually; some method of aggregating them both for modelling and for control is appealing so that they can be represented collectively. It would also be preferable to limit the complexity of the controlled devices' dynamic behavior for easy integration with higher‐level (i.e., higher‐authority) controllers in the cascade. This paper describes a method combining these control goals based on geometric flexibility regions, constrained optimization, and transfer function considerations to enforce approximated first‐order transfer function behaviour at the bus. Time‐domain simulations are used for validation and demonstration. [ABSTRACT FROM AUTHOR]

This study aims to determine the variables that millennials consider most important when making a job choice. Information is collected through an online survey of a representative sample of 325 millennials from the Coquimbo region (Chile), born between 1981 and 1995. A Job Preference Index (ILP) is established to arrive at a model with the most important variables that a millennial considers when choosing an organization to work for. The results show that variables such as teamwork, economic projection, and diversity and inclusion have an important and significant impact on job choice, with coefficients of 0.132, 0.135, and 0.107 respectively. It is concluded that millennials share similar preferences about their likes and other relevant variables for their job choices, regardless of their gender, marital status, and hobbies. [ABSTRACT FROM AUTHOR]

Warming across the globe is expected to alter the strength and amount of regional precipitation, but there is uncertainty associated with the magnitude of these expected changes, and also how these changes in temperature and the hydrologic cycle will affect humans. For example, the climate in central-south Chile is projected to become significantly warmer and drier over the next several decades in response to anthropogenically driven warming, but these anthropogenic changes are superimposed on natural climate variability. The stable isotope composition of meteoric water provides significant information regarding the moisture source, pathways, and rain-out history of an air mass, but precipitation samples suitable for stable isotope measurements require long-term placement of field equipment making them difficult to obtain. The International Atomic Energy Agency (IAEA) Global Network of Isotopes in Precipitation (GNIP) stations generate isotopic and ancillary data of precipitation from many locations around the world, but remote areas of developing countries like Chile typically have sparse networks of meteorological stations, which inhibit our ability to accurately model regional precipitation. Central-south Chile, in particular, has a sparse network of GNIP stations and, as a result, the isotopic composition of meteoric water is underrepresented in the global database complicating efforts to constrain modern day hydroclimate variability as well as paleohydrologic reconstruction for southern South America. In this study, we measured the stable isotope compositions of hydrogen (δ2H) and oxygen (δ18O) in surface lacustrine waters of central-south Chile to determine what physical and/or climatic features are the dominant controls on lacustrine δ18O and δ2H composition, assess whether or not the isotopic composition of the lakes record time-averaged isotope composition of meteoric water, and determine whether an isoscape map based on lake surface waters could predict the H and O isotope compositions of precipitation at the few GNIP stations in the region. [ABSTRACT FROM AUTHOR]

The study of fatty acid biomarkers in trophic structures at sub-polar latitudes is fundamental in describing energy fluxes across ecosystems characterized by complex inter-specific interactions. Due to the presence of certain essential fatty acids obtained exclusively from predator–prey interactions, fatty acid biomarkers are widely used to identify trophic interactions. This study analyzed fatty acid compositions in three species inhabiting a relatively pristine Patagonian fjord. This fjord is geographically difficult to access, so there are very little sampling opportunities, biological and oceanographic information. In the three species collected (Ctenodiscus australis (Loven in Lütken 1871) (Echinodermata, Asteroidea, Ctenodiscidae); Munida gregaria (Fabricius 1793) (Arthropoda, Malacostraca, Munididae); Eleginops maclovinus (Cuvier 1830) (Chordata, Actinopterygii, Eleginopsidae)) along this remote area were evaluated their fatty acid trophic markers as a tool to differentiate dietary components and dietary habits. The study reported significant differences in the amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), with the highest concentrations of all fatty acids in M. gregaria. The last suggests that M. gregaria is considered as a good quality food source or biological component that might support the fjord trophic web in the Southern Hemisphere. The results describe diet compositions in sampled species, and differences among species for fatty acid compositions and proportions. This provides an initial basis for future modeling or projecting how benthic ecosystems of fjords and Patagonian channels respond to food intake, particularly in environments associated with glacial systems characterized by a low phytoplankton biomass and greater sensitivity to climate variability. [ABSTRACT FROM AUTHOR]

We test different implementations of the halo occupation distribution (HOD) model to reconstruct the spatial distribution of galaxies as predicted by a version of the L-GALAXIES semi-analytical model (SAM). We compare the measured two-point correlation functions of the HOD mock catalogues and the SAM samples to quantify the fidelity of the reconstruction. We use fixed number density galaxy samples selected according to stellar mass or star formation rate (SFR). We develop three different schemes to populate haloes with galaxies with increasing complexity, considering the scatter of the satellite HOD as an additional parameter in the modelling. We modify the SAM output, removing assembly bias and using a standard Navarro–Frenk–White density profile for the satellite galaxies as the target to reproduce with our HOD mocks. We find that all models give similar reproductions of the two-halo contribution to the clustering signal, but there are differences in the one-halo term. In particular, the HOD mock reproductions work equally well using either the HOD of central and satellites separately or using a model that also accounts for whether or not the haloes contain a central galaxy. We find that the HOD scatter does not have an important impact on the clustering predictions for stellar mass-selected samples. For SFR selections, we obtain the most accurate results assuming a negative binomial distribution for the number of satellites in a halo. The scatter in the satellites HOD is a key consideration for HOD mock catalogues that mimic ELG or SFR-selected samples in future galaxy surveys. [ABSTRACT FROM AUTHOR]

Abstract The Mar Menor is the largest lagoon along the Spanish Mediterranean coast. It suffers from eutrophication and algal blooms associated with intensive agricultural activities and urban pressure in the surrounding Campo de Cartagena plain. A balanced discharge of groundwater, carrier of algal nutrients such as nitrate, is essential to ensure the integrity of the coastal lagoon and the availability of groundwater resources inland. We here present a 3D hydrogeological model of the unconfined Quaternary aquifer that discharges into the lagoon. The model couples both surface water balance and groundwater dynamics and has been calibrated to available data in the period 2000–2016. The calibrated model allows understanding of the current state of the aquifer and its link to the lagoon. The potential discharge has been quantified in both space and time and falls between 69.5 and 84.9 hm3/yr during dry and wet periods, respectively (with values of nitrate discharge of 11.4–11.8 Mkg/yr in the absence of aquifer sink terms, e.g., leakage to deeper aquifers and pumping from groundwater wells). The predictive capabilities of the calibrated model can be used to test the impact of different integrated management scenarios on the surface-groundwater dynamics of the catchment. Three plausible management scenarios are proposed that include localized and distributed groundwater pumping (drains and groundwater wells, respectively). Results show the effectiveness of the scenarios in reducing the groundwater and nitrate discharge into the lagoon. The disadvantages of the proposed scenarios, including potential seawater intrusion, need to be balanced with their relative merits for the sustainable development of the region and the survival of the Mar Menor ecosystem. The modelling approach proposed provides a valuable tool for the integrated and holistic management of the Campo de Cartagena-Mar Menor catchment and should be of great interest to similar hydrological systems with high ecological value. Graphical abstract Unlabelled Image Highlights • Mar Menor coastal lagoon is a key example of eutrophication by agricultural activity. • The sustainable development of Mar Menor must be considered as a land-sea continuum. • A numerical model tests the effectiveness of groundwater management strategies. • The model provides a decision support tool for policy makers. [ABSTRACT FROM AUTHOR]

Abstract The radial and background distribution functions of Quantum Hard Spheres (QHS) are studied and analytical expressions are obtained that can be used to evaluate perturbation terms of the Helmholtz free energy for quantum fluids like hydrogen and helium. The provided analytical expressions were obtained from Path-Integral Monte Carlo (PIMC) simulations for quantum hard spheres (QHS) and results are given for the first perturbation terms of model systems like quantum square-well and Lennard-Jones fluids. As part of this study, we use the Clausius virial theorem and the mean-value theorem from integral calculus to provide a generalization of the standard contact-value/pressure relation for classical hard-spheres, in order to obtain the QHS pressure. Within this information, it is also possible to provide extensions to the quantum regime of the zero-separation theorems. Graphical Abstract Highlights • Path-Integral MC Simulations/Thermodynamic Perturbation Theory applied to quantum fluids. • Parametrization of the the radial distribution of Quantum Hard Spheres is provided. • The Clausius virial and zero-separation theorems are extended to the quantum regime. • Results are important for the modeling of associating liquids. [ABSTRACT FROM AUTHOR]

Highlights • Models based on VCI/TCI explained 70% of wheat and barley yield level annual variability. • Validation tests at agricultural districts confirmed better fit of VCI/TCI-based crop models compared to SPI-based models. • Both families of indices (meteorological and satellite) fail to explain yield variability of maize, mostly rainfed in Spain. • VCI/TCI-based models performed better than SPI-based as in-season, real-time yield forecasting tools. Abstract In the context of global warming, as drought episodes become increasingly frequent, it is crucial to accurately measure the impacts of droughts on the overall performance of agrosystems. This study aims to compare the effectiveness of meteorological drought indices against satellite-based agronomical drought indices as crop yield explanatory factors in statistical models calibrated at a local scale. The analysis is conducted in Spain using a spatially detailed, 12-year (2003–2015) dataset on crop yields, including different types of cereals. Yields and drought indices were spatially aggregated at the agricultural district level. The Standardised Precipitation Index (SPI), computed at different temporal aggregation levels, and two satellite-based drought indices, the Vegetation Condition Index (VCI) and the Temperature Condition Index (TCI), were used to characterise the dynamics of drought severity conditions in the study area. Models resting on satellite-based indices showed higher performance in explaining yield levels as well as yield anomalies for all the crops evaluated. In particular, VCI/TCI models of winter wheat and barley were able to explain 70% and 40% of annual crop yield level and crop yield anomaly variability, respectively. We also observed gains in explanatory power when models for climate zones (instead of models at the national scale) were considered. All the results were cross-validated on subsamples of the whole dataset and on models fitted to individual agricultural districts and their predictive accuracy was assessed with a real-time forecasting exercise. Results from this study highlight the potential for including satellite-based drought indices in agricultural decision support systems (e.g. agricultural drought early warning systems, crop yield forecasting models or water resource management tools) complementing meteorological drought indices derived from precipitation grids. [ABSTRACT FROM AUTHOR]

Ecological processes that are behind distributions of species that inhabit isolated localities, complex disjunct distributions, remain poorly understood. Traditionally, vicariance and dispersion have been proposed as explanatory mechanisms that drive such distributions. However, to date, our understanding of the ecological processes driving evolution of ecological niches associated with disjunct distributions remains rudimentary.Here, we propose a framework to deconstruct drivers of such distribution using World's most widespread freshwater fish Galaxias maculatus as a model and integrating marine and freshwater environments where its life cycle may occur. Specifically, we assessed ecological and historical factors (Gondwanan vicariance, marine dispersion) and potential dispersion (niche‐tracking) that explain its distribution in the Southern Hemisphere.Estimated distribution was consistent with previously reported distribution and mainly driven by temperature and topography in freshwater environments and by primary productivity and nitrate in marine environments. Niche dynamics of G. maculatus provided evidence of synergy between vicariance and marine dispersion as explanatory mechanisms of its disjunct distribution, suggesting that its ecological niche was conserved since approximately 30 Ma ago.This integrated assessment of ecological niche in marine and freshwater environments serves as a generic framework that may be applied to understand processes underpinning complex distributions of diadromous species. [ABSTRACT FROM AUTHOR]

The diagnosis of an unknown primary tumor is usually difficult due to its clinicalpathologicalbehavior; its clinical manifestation is delayed so that the integration ofa diagnostic protocol from a symptom or nonspecific clinical finding determines thedelay of its approach. The characteristics of this tumor give it the minimum necessarytools to leave its niche of origin early, disseminating and staying distant from it, that is,an early metastasis. The development of molecular techniques that surpass the classicpathology has been an invaluable tool for its classification, having an absolute intentionto separate those potentially sensitive to oncological treatment from those that are not.Without distinctive features that allow supposing it, before a seasoned clinician theinitial suspicion of this entity is the best diagnostic tool. [ABSTRACT FROM AUTHOR]

The SAFT-VR-Mie approach is applied to model quantum fluids following a method presented previously on the combined use of thermodynamic perturbation theory (TPT) and path-integral Monte Carlo (PIMC) simulations to describe a quantum square-well (QSW) fluid. In this communication we consider a system of N particles contained within a volume V interacting via a quantum Lennard-Jones potential (QLJ) with de Broglie's thermal wavelength , where m denotes the particle's mass, T is the temperature and h and k are the Planck's and Boltzmann's constants, respectively. The method is based on the exact analogy between the discretised path-integral formalism of Quantum Mechanics and the partition function of a classical system composed of necklace molecules. The Zwanzig's expansion is implemented in order to obtain the QLJ's first-perturbation term, , from PIMC simulations. An effective Mie potential with a variable repulsive parameter range and fixed attractive parameter, , is obtained by mapping to the classical expression provided by the SAFT-VR-Mie value, . The thermodynamics of the QLJ system is obtained using the SAFT-VR-Mie equation of state and applied to obtain accurate predictions for molecular hydrogen's isotherms when . [ABSTRACT FROM AUTHOR]

Paleolimnological studies in western South America, where meteorological stations are scarce, are critical to obtain more realistic and reliable regional reconstructions of past climate and environmental changes, including vegetation and water budget variability. However, climate and environmental geochemical indicators must be tested before they can be applied with confidence. Here we present a survey of lacustrine surface sediment (core top, 0 to ~1 cm) biogeochemical proxies (total organic carbon [TOC], total nitrogen [TN], carbon/nitrogen ratio [C/N ratio] and bulk organic δ 13 C and total δ 15 N) from a suite of 72 lakes spanning the transition from a Mediterranean climate with a patchwork of cultivated vegetation, pastureland, and conifers in central Chile to a rainy temperate climate dominated by broadleaf deciduous and evergreen forest further south. Sedimentary data are compared to the latitudinal and orographic climatic trends of the region based on the climatology (precipitation and temperature) produced with Climate Forecast System Reanalysis (CFSR) data and the modern Southern Hemisphere Westerly Winds (SWW) location. The geochemical data show inflection points at ~42°S latitude and ~1500 m elevation that are likely related to the northern limit of influence of the SWW and elevation of the snow line, respectively. Overall the organic proxies were able to mimic climatic trends (Mean Annual Precipitation [MAP] and temperature [MAT]), indicating that they are a useful tool to be included in paleoclimatological reconstruction of the region. [ABSTRACT FROM AUTHOR]

The design of efficient three‐phase induction motors is a challenge for engineering; therefore, new design techniques are continually being proposed. For example, efficiency is in conflict with manufacturing cost, which leads to the use of multi‐objective optimisation techniques to solve this engineering problem. Nevertheless, this study shows that the way of accurately modelling the behaviour of the motor is as important as the optimisation method itself. Thus, the study discusses fundamental considerations in the motor model as part of a proposed methodology for the design of highly efficient three‐phase squirrel cage induction motors. For this purpose, the motor is modelled in two ways: an analytical equivalent circuit and the finite element method, which are validated with data obtained from laboratory tests. The main contribution of this study is to show for the first time the required characteristics of the analytical model used as part of a multi‐objective optimisation problem to have a suitable accuracy with a competitive runtime. Moreover, the problem is solved using three bio‐inspired optimisation algorithms: non‐dominated sorting genetic algorithms II, non‐dominated sorting particle swarm optimisation and bacterial chemotaxis multi‐objective optimisation algorithm. The methodology is tested in the optimal redesign of a two‐pole, 3.7 kW, IE2 efficiency motor, for which the efficiency and cost were improved. [ABSTRACT FROM AUTHOR]

Leaf cuticular waxes are one of the most important environment-plant interaction structural systems that enable desert plants to withstand extreme climatic conditions. We present a long chain n -alkyl lipids study in fresh plant leaves and rodent palaeomiddens collected along an elevational gradient in the south-central Atacama Desert of Chile, covering six different vegetation belts: Steppe (4500-4000 m asl), Puna (4000-3300 m asl), pre-Puna (3300-2400 m asl), Absolute Desert (2400-1000 m asl) and Coastal Desert (1000-0 m asl). The 28 rodent palaeomiddens analyzed from Quebrada Incahuasi (25.6 °S, 3600 m asl) span the last 17,000 years. Modern-day distribution of long-chain n -alkanes and n -alkanoic acids varies among the dominant plant associations of the Atacama Desert. These plants show a species-specific chemotaxonomy linked to the climatic conditions. Furthermore, differences in average chain length (ACL) and carbon preference index (CPI) suggest that these plant communities are highly adapted to extreme environmental conditions. The sum of leaf wax n -alkanes was highest under wet conditions, while n -alkanoic acids (between n - C 24 and n - C 28) increased with hyperaridity. Similarly, analysis of n -alkane time series from palaeomiddens showed that the greatest changes in leaf wax n -alkane distributions (ACL and CPI) corresponded to the greatest increases in moisture during the Central Andean Pluvial Event (CAPE; between 18 and 9 ka cal BP) and the Late Holocene. The shift in the palaeomidden n -alkane distributions is corroborated by the relative abundance of rainfall-dependent extra-local taxa. This is the first study to report leaf wax content obtained from ancient rodent middens, and shows promising results as a robust hydroclimate proxy for the Atacama Desert region. • n-Alkyl leaf waxes obtained from ancient Atacama rodent middens can be used to infer past climate change. • An elevational survey of leaf cuticular waxes in the Atacama Deserts shows that their composition varies at the ecosystem scale. • Ancient middens reveal significant responses in n-alkane composition and plant macrofossils to millennial-scale hydroclimate shifts over the past 17,000 years. • Our reconstruction traces the Central Andean Pluvial Events and shows that paleomiddens are a valuable source of leaf wax. [ABSTRACT FROM AUTHOR]

Climate variability during Pleistocene glacial/interglacial transitions is well documented in marine and ice-sheet isotopic records, but terrestrial records showing the continental response to these transitions are scarce, especially for earlier in the Pleistocene. Cyclic intervals of warm interglacial and cold glacial conditions preserved in terrestrial records such as lake sediments provide opportunities to probe the biosphere's response to climate change. In this study, we track climate and plant type changes, specifically the presence of C3 and C4 plants, using the abundance and δ 13 C signatures of leaf waxes in paleolacustrine sediments from Valles Caldera in New Mexico. Through these changes, we assess the response of vegetation to climate variability in southwestern North America through two mid-Pleistocene glacial/interglacial transitions (Marine Isotope Stage [MIS] 14/13 and 12/11). Leaf wax data show that the C3 forest taxa were dominant through the entire record whereas C4 plants, better adapted to warm conditions and competitive under water stress, are favored during warming and extended arid periods during interglacials. The δ 13 C signature in leaf wax n -alkanes suggests that C4 plants persisted in the watershed throughout the interglacials and that some summer rainfall (which is required to support C4 grasses) was maintained even during prolonged dry periods. The abundance and carbon isotope composition of leaf waxes together with new MBT/CBT (methylation index of branched tetraethers/cyclization index of branched tetraethers) temperature data confirm warmer and more arid conditions during MIS 13 than during MIS 11, in spite of relatively low greenhouse gas concentrations during MIS 13. This suggests that variations in incoming solar radiation have played a major role in regulating the surface temperature, regional hydrological systems and vegetation in southwestern North America, likely through changes in the North American Monsoon coupled with variations in the location of the mid-latitude westerlies. [ABSTRACT FROM AUTHOR]

This work explores the use of satellite-based vegetation indices (VI) to study groundwater use in a semi-arid agricultural irrigated area. The objective is to obtain insight in spatial and temporal patterns and differences in groundwater usage of perennial (mainly fruit trees) and seasonal crops (mainly row vegetable crops) under varying climatic conditions. Cropping intensities of seasonal crops are derived for each sector and irrigation water applied (IWA) is calculated using VI-based (NDVI from MODIS) actual evapotranspiration estimates and local efficiency factors. Groundwater use is then derived as the residual of total IWA and surface water supplies for each sector and crop type. The results of IWA following this methodology were compared with survey-based results for two crop types. Results correlated well, but deviate most during drought period, likely due to salt leaching practices. Monthly groundwater use patterns and spatial and temporal differences during normal water availability and drought conditions are reported. On average, about 50% of irrigation water is extracted from aquifers, but during droughts this percentage increases considerably. Perennial crops show sharper increases in groundwater use under such conditions than seasonal crops. Overall, seasonal crops put more pressure on the groundwater resource than perennial crops. Our results and methodology will be useful for water resource managers, and policy makers concerned with the role of groundwater resources on the sustainability of semiarid agricultural regions. [ABSTRACT FROM AUTHOR]

We study the alignment of dark matter haloes with the cosmic web characterized by the tidal and velocity shear fields. We focus on the alignment of their shape, angular momentum and peculiar velocities. We use a cosmological N-body simulation that allows us to study dark matter haloes spanning almost five orders of magnitude in mass (109–1014) h−1 M⊙ and spatial scales of (0.5–1.0) h−1 Mpc to define the cosmic web. The strongest alignment is measured for halo shape along the smallest tidal eigenvector, e.g. along filaments and walls, with a signal that gets stronger as the halo mass increases. In the case of the velocity shear field only massive haloes >1012 h−1 M⊙ tend to have their shapes aligned along the largest tidal eigenvector, i.e. perpendicular to filaments and walls. For the angular momentum we find alignment signals only for haloes more massive than 1012 h−1 M⊙ both in the tidal and velocity shear fields where the preferences is to be parallel to the middle eigenvector; perpendicular to filaments and parallel to walls. Finally, the peculiar velocities show a strong alignment along the smallest tidal eigenvector for all halo masses; haloes move along filaments and walls. The same alignment is present with the velocity shear, albeit weaker and only for haloes less massive than 1012 h−1 M⊙. Our results show that the two different algorithms used to define the cosmic web describe different physical aspects of non-linear collapse and should be used in a complementary way to understand the cosmic web influence on galaxy evolution. [ABSTRACT FROM PUBLISHER]

Nitrogen (N) isotope ratios (15N/14N) provide integrative constraints on the N inventory of the modern ocean. Anaerobic ammonium oxidation (anammox), which converts ammonium and nitrite to dinitrogen gas (N2) and nitrate, is an important fixed N sink in marine ecosystems. We studied the so far unknown N isotope effects of anammox in batch culture experiments. Anammox preferentially removes 14N from the ammonium pool with an isotope effect of +23.5% to +29.1%, depending on factors controlling reversibility. The N isotope effects during the conversion of nitrite to N2 and nitrate are (1) inverse kinetic N isotope fractionation associated with the oxidation of nitrite to nitrate (-31.1 ± 3.9%,), (ii) normal kinetic N isotope fractionation during the reduction of nitrite to N2 (+16.0 ± 4.5%o), and (iii) an equilibrium N isotope effect between nitrate and nitrite (-60.5 ± 1.0%o), induced when anammox is exposed to environmental stress, leading to the superposition of N isotope exchange effects upon kinetic N isotope fractionation. Our findings indicate that anammox may be responsible for the unresolved large N isotope offsets between nitrate and nitrite in oceanic oxygen minimum zones. Irrespective of the extent of N isotope exchange between nitrate and nitrite, N removed from the combined nitrite and nitrate (NOx) pool is depleted in 15N relative to NO,,. This net N isotope effect by anammox is superimposed on the N isotope fractionation by the cooccurring reduction of nitrate to nitrite in suboxic waters, possibly enhancing the overall N isotope effect for N loss from oxygen minimum zones. [ABSTRACT FROM AUTHOR]

The coupling of subseafloor microbial life to oceanographic and atmospheric conditions is poorly understood. We examined diagenetic imprints and lipid biomarkers of past subseafloor microbial activity to evaluate its response to glacial-interglacial cycles in a sedimentary section drilled on the Peruvian shelf (Ocean Drilling Program Leg 201, Site 1229). Multiple and distinct layers of diagenetic barite and dolomite, i.e., minerals that typically form at the sulfate−methane transition (SMT), occur at much shallower burial depth than the present SMT around 30 meters below seafloor. These shallow layers co-occur with peaks of 13C-depleted archaeol, a molecular fossil of anaerobic methane-oxidizing Archaea. Present-day, non-steady state distributions of dissolved sulfate also suggest that the SMT is highly sensitive to variations in organic carbon flux to the surface shelf sediments that may lead to shoaling of the SMT. Reaction-transport modeling substantiates our hypothesis that shallow SMTs occur in response to cyclic sediment deposition with a high organic carbon flux during interglacials and a low organic carbon flux during glacial stages. Long diffusion distances expectedly dampen the response of deeply buried microbial communities to changes in sediment deposition and other oceanographic drivers over relatively short geological time scales, e.g., glacial-interglacial periods. However, our study demonstrates how dynamically sediment biogeochemistry of the Peru Margin has responded to glacial-interglacial change and how these changes are now preserved in the geological record. Such changes in subsurface biogeochemical zonation need to be taken into account to assess the role of the subseafloor biosphere in global element and redox cycling. [ABSTRACT FROM AUTHOR]

Abstract: Semiarid karst landscapes represent an important ecosystem surrounding the Mediterranean Basin for which little is known on runoff generation. Knowledge of the sources and patterns of variation in infiltration–runoff processes and their controls is important for understanding and modelling the hydrological functions of such ecosystems. The objectives of this paper are to determine the infiltration rates and their controls in a representative mountain karst area (Sierra de Gádor, SE Spain) at micro-plots and to investigate the integrated response of rainfall on a typical hillslope. Rainfall simulations in micro-plots and natural rainfall-runoff monitoring on a hillslope were carried out complementarily. We investigated the role of soil surface components (vegetation, rock outcrop, fracture, and soil crust), topographic position, antecedent soil moisture, and rainfall characteristics in regulating infiltration–runoff processes. Results of rainfall simulation revealed the importance of vegetation cover and the presence of rock fractures in promoting the infiltration in the limestone karst landscape, while bare patches and rock outcrops acted as sources for runoff. All plots with >50% vegetation cover had no runoff with up to 55mmh−1 of simulated rain. In contrast, nearly all bare plots had runoff under the same simulated rain, with runoff coefficients ranging from 3.1 to 20.6% on dry soil surface conditions, and from 2.0 to 65.4% on wet soil surfaces. Runoff coefficients amounted to 59.0–79.5% for rock outcrops without cracks, but were drastically reduced by the presence of cracks. The surfaces with rock fragments resting on the soil (generally located in the middle of the slopes) prevented more effectively the runoff generation than those surfaces where rock fragments were embedded in the top soil. Antecedent soil moisture had significant impact on runoff generation, with wet soil having doubled runoff coefficient, shortened time to runoff, and increased runoff rate compared to the same but dry soil. Linear regressions indicated that the main controls for constant infiltration rate were the cover percentages of vegetation and litter, plus rainfall intensity; while the major controls for runoff coefficient were the bare soil and vegetation coverage, plus rainfall intensity. High infiltration rates measured at the micro-plots agreed with low intra-event runoff coefficients (mostly below 1%) observed under natural rainfalls at the hillslope. Runoff depth and coefficient at the hillslope was significantly correlated with rainfall depth, maximum hourly rainfall intensity and antecedent precipitation over 20days (AP20). During the 1.5-year monitoring period from Sep-2003 to Mar-2005, the overall infiltration was 41% of the total rainfall amount and the maximum infiltration rate was almost 94% of the largest single rainfall event. The results from this study contribute to improved understanding of the magnitude and controls of the surface runoff in semiarid karst mountain areas. [Copyright &y& Elsevier]

Summary: Besides precipitation inputs, evapotranspiration of irrigated and natural oases, i.e. riparian and phreatophytic ecosystems, of rain-shadow deserts is strongly influenced by lateral water inputs supplied by mountain rivers and foothill-recharged aquifers. A better understanding of these supplies and their imprint on the water consumption of those inflow dependent ecosystems (IDEs) across arid regions is critical to manage agricultural outputs and ecosystem conservation, and the hydrological trade-offs that emerge among them. Actual operative satellite and physically-based algorithms able to map evapotranspiration (ET) rates at regional scales still fail when they are applied in ungauged regions because of their high parameterization and meteorological data requirements. We introduce an ecological and satellite-based approach to explore the impacts of external water supplies on arid ecosystems, focusing on the Central Monte desert and its water supplies from the Andean Cordillera, in Argentina. Mean annual precipitation (MAP) and the Enhanced Vegetation Index (EVI) from MODIS imagery, used as a surrogate of ET, were the input variables of our empirical model. Two related biophysical indexes were generated for the whole territory of interest based on a MAP–EVI regional function calibrated for the region: the EVI Anomaly (i.e. deviation from a reference with similar MAP) and the ET Anomaly (i.e. additional water consumption besides MAP). These indexes allowed us to identify IDEs and to quantify the impact of remote lateral inflows as well as local constrains on the water balance of rangelands, and irrigated and natural oases. The performance of this satellite-based approach was evaluated through comparisons with independent ET estimates based on plot (known crop coefficients) and basin (measured water budgets) scale approaches. Relative errors in the 2–18% range at plot and basin scale are in agreement with those uncertainties reported by other satellite and physically-based approaches. Our approach provides a simple yet robust diagnostic tool to characterize water balance in arid regions, aimed to improve the identification of inflow dependent ecosystems and their management under the demanding pressures of land use and climate change. [Copyright &y& Elsevier]

[Display omitted] • Knowledge of leaf waxes of South American Temperate Forest plant species is lacking. • Three leaf wax classes on twelve dominant plant species were analyzed. • The n -alkanoic acids, n -alkanes and n -alkanols differ within and among species. • It is possible to differentiate among species using leaf wax classes. • A potential use of leaf wax classes as a chemotaxonomic biomarker is proposed. Plant leaf waxes are used as vegetation biomarkers in several archives (i.e. soils, lake and marine sediments), study of these compounds in modern plants is needed to makes their application and interpretation more robust. However, in the South American Temperate Forest (STF), few species have been studied. The main goal of this research was to characterize twelve dominant modern species of the STF using three classes of leaf wax compounds, n -alkanoic acids, n -alkanes and n -alkanols. In addition, we evaluate the potential of leaf waxes as a vegetation and chemotaxonomic biomarker in the region, considering species that were found in different sampling sites and therefore environmental conditions. Clear differences among leaf wax abundance (μg/g) and ACL (average chain length) within and among the twelve species were found. Only the ACL of n -alkanoic acids and n -alkanols allows differentiation between leaf habit species (i.e. evergreen vs. deciduous), with high values associated with evergreen and low values with deciduous plants. This study differentiates the five species found in more than one site (i.e. different environmental condition) using different combinations of leaf waxes and in addition using only n -alkanes. It was not possible to differentiate among all sites with any combination of leaf waxes. The differences in the distribution of leaf waxes among species is an expected pattern in the study area, and it seems reliable to use the ACL as a vegetation biomarker differentiating between evergreen and deciduous species. The clear chemotaxonomic differences among the five species exposed to different and natural environmental conditions and the high preservation potential of the study area allow us to suggest that leaf waxes are likely a reliable tool to be incorporated in quantitative models to track vegetation and may be useful as a chemotaxonomic biomarker at the species level. [ABSTRACT FROM AUTHOR]

Abstract: Quick overland flow peaks observed in runoff hydrographs from rainfall experiments carried out on mica schist soils in Rambla Honda (SE Spain) suggest development of soil water repellency (SWR). In order to spatially characterize its occurrence and severity and the factors controlling it, potential water repellency was measured in 120 soil samples using the WDPT test at laboratory conditions. Actual water repellency measurements were additionally performed at field conditions in order to increase our knowledge about the occurrence of this phenomenon. Samples were taken in bare soils (n = 23), beneath plant clumps of Retama sphaerocarpa (n = 23) and Anthyllis cytisoides (n = 10) and from soils affected by rabbit latrines (n = 9). Soil organic matter was also determined in 47 selected samples with a broad range of potential water repellency values. Results indicate that occurrence of SWR in Rambla Honda (potential water repellency values) varies in the three soil dimensions, areal and depth. The areal variation is due to the patchy pattern of organic matter and the variation with depth of the washed-in layer of sieving crusts developed in colluvial and alluvial soils after abandonment by agriculture. These layers act as physical barriers that restrict or impede the translocation of hydrophobic compounds to deeper layers. Such three-dimensional heterogeneity stresses the importance of the sampling scheme used for adequate SWR assessment. The severity of water repellency is generally reduced in this area because of the relatively scarce organic matter content and its spatial variability. A weak exponential relationship was found between the severity of potential water repellency and total organic carbon (r 2 = 0.38; p-value < 0.01). Extreme values of actual and potential water repellency were found in rabbit latrines, stressing the importance of macrofauna in its development. Water repellency has an important impact on the local hydrology controlling runoff–runon between vegetated and bare patches, and possibly flash flooding during heavy rains in early autumn or after long dry periods. Review of a series of runoff hydrographs from previous rainfall simulations has distinguished four types of runoff patterns based on the occurrence of SWR. [Copyright &y& Elsevier]

Abstract: Vegetation and rock fragments have a profound impact on runoff generation in the dolines of the Sierra de Gádor, southeastern Spain. This study investigated the effect of vegetation and rock fragments on unsaturated hydraulic conductivity [K(h)] in three limestone dolines and examined whether variation in K(h) was consistent with differences in runoff from simulated rainfall. Tension infiltrometers were used to measure unsaturated hydraulic conductivity at three pressure heads (h) of −30, −60 and −120 mm at 70 locations within the three dolines. Generally, the trends of the K(h) were consistent with the simulated rainfall data and accounted for difference in runoff for the vegetated surfaces. Vegetation resulted in high infiltration with unsaturated hydraulic conductivities at −30 and −60 mm are significantly greater for the vegetated surface than for the rock fragment covered surface and bare soil surface. Rock fragments had no obvious effect on soil hydraulic conductivity as compared with bare soils. The K(h) of the non-crusted soil were 2–5 times higher than that of the crusted soil. The K(h) decreased with increasing tensions, K(60) and K(120) were only 8.4 and 0.89%, respectively, of K(30) for the vegetated surfaces, and were about 30 and 8.7%, respectively, of K(30) for both rock fragment covered surfaces and bare soils, suggesting that pores in the 0.5- to 1-mm diameter range dominate flow under unsaturated conditions. There were significant differences in K(h) among the different topographic units of the dolines, and K(h) tended to be higher in the upper position than in the lower position of the doline. [Copyright &y& Elsevier]

Summary: An ecohydrological water balance method based on the hydrological equilibrium hypothesis was developed to estimate long-term annual recharge rates in semiarid karstic landscapes. Recharge was predicted from the difference between long-term annual precipitation and evapotranspiration rates. A multiple regression interpolation approach was used to compute precipitation. Evapotranspiration was quantified from the deviations between the observed local value of the normalised difference vegetation index (NDVI) and, the predicted minimum and maximum NDVI values for two hydrologically-well defined reference conditions representing the minimum and maximum vegetation density given a local long-term water availability index. NDVI values for the reference conditions (NDVImin and NDVImax) were estimated from an empirically-based boundary analysis. Evapotranspiration rates for the reference conditions were estimated using a monthly water budget model that integrates the roles of the soil water holding capacity and a climate-driven evaporative coefficient (k) representing the mean annual conductance of the vegetation canopy. The methodology was tested in Sierra de Gádor (SE Spain), where predicted evapotranspiration and recharge rates compared well with local and regional scale estimates obtained from independent methods. A sensitivity analysis showed that NDVImax and k are the parameters that mostly affect our model’s evapotranspiration and recharge estimates. [Copyright &y& Elsevier]

Abstract: We compared the signals of several water column properties (upwelling intensity, sea level anomaly, temperature, nutrients, dissolved oxygen, chlorophyll-a, and surface sediments) of the continental shelf off Concepción (36°S) during the 1997–1998 El Niño with those of a normal year (2002–2003). We found that the primary hydrographic effect of El Niño 1997–1998 was a reduction in the input of nutrient-rich, oxygen-poor Equatorial Subsurface Water over the shelf. This affected the biology of the water column, as evidenced by the reduced phytoplankton biomass. Surface sediment properties (biogenic opal, organic carbon, bulk δ15N) observed during El Niño 1997–1998 reflected a reduced export production and the sediments failed to show the water column seasonality that occurs under normal conditions. In addition, weakened denitrification and/or upper water column fertilization could be inferred from the sedimentary δ15N. Although diminished, export production was preserved in the surface sediments, revealing less degraded organic matter in the upwelling period of the El Niño year than in the normal year. We suggest that the fresher organic material on the seafloor was probably associated with a severe reduction in the polychaete Parapronospio pinnata, which is considered to be the most important metazoan remineralizer of organic carbon at the sediment–water interface in the study area. [Copyright &y& Elsevier]

Abstract: Rock fragments (RFs) at the soil surface have great effects on the intensity of various hydrologic and geomorphic processes. However, little information is available on the spatial distribution of rock fragments (RF) in the dolines, which may be of importance in understanding overland flow and subsequent recharge in limestone karst landscapes. This study analysed spatial variability of RF cover and size in different topographic positions (top, upper, middle and lower position) in three dolines in Sierra de Gádor (Almería province, south-east Spain). The results indicated that cover percentage of small RFs (5–20 mm) increased but large RF cover (250–600 mm and >600 mm) decreased from the upper position to the lower position of the dolines. Small RFs were usually resting on the soil surface while most large RFs tended to be partly embedded in the soil surface. Total RF cover and D 50 (median diameter) of the surface RFs greater than 5 mm tended to increase with slope gradient. [Copyright &y& Elsevier]

In this paper we characterize the unemployment rate for the main cities of the Bío Bío Region using the state-space multivariate approach, in order to isolate and evaluate their tendency and seasonal components. We present theoretical expressions for each structural model for monthly unemployment rate data which spans between I.1996 and XII.2005. We use an additive multivariate structural model for the cities of Chillán, Concepción, Gran Concepción and Talcahuano, an additive bivariant structural model for Coronel and Lota, and an additive univariate structural model for Arauco and Los Angeles. The main results show, firstly, that the estimated state-space approach models present a good explanation power (MAPE is less than 8 per cent for four cities); secondly, the hypothesis which states that seasonal peak levels for unemployment rate are related to cities strongly linked with the primary sector (raw materials) is verified, thirdly, quantifying the seasonal component for unemployment series in each city gives useful information to local policy-makers, because it can determine the optimal length for emergency employment plans. [ABSTRACT FROM AUTHOR]

Recent analyses show that ΛCDM-based models optimized to reproduce the clustering of massive galaxies overestimate their gravitational lensing by about 30 per cent, the so-called lensing is low problem. Using a state-of-the-art hydrodynamical simulation, we show that this discrepancy reflects shortcomings in standard galaxy–halo connection models rather than tensions within the ΛCDM paradigm itself. Specifically, this problem results from ignoring a variety of galaxy formation effects, including assembly bias, segregation of satellite galaxies relative to dark matter, and baryonic effects on the matter distribution. All these effects contribute towards overestimating gravitational lensing, and when combined, explain the amplitude and scale dependence of the lensing is low problem. We conclude that simplistic galaxy–halo connection models are inadequate to interpret clustering and lensing simultaneously, and that it is crucial to employ more sophisticated models for the upcoming generation of large-scale surveys. [ABSTRACT FROM AUTHOR]

We present computer simulation and theoretical results for a system of N Quantum Hard Spheres (QHS) particles of diameter σ and mass m at temperature T, confined between parallel hard walls separated by a distance H σ , within the range 1 ≤ H ≤ ∞ . Semiclassical Monte Carlo computer simulations were performed adapted to a confined space, considering effects in terms of the density of particles ρ * = N / V , where V is the accessible volume, the inverse length H − 1 and the de Broglie's thermal wavelength λ B = h / 2 π m k T , where k and h are the Boltzmann's and Planck's constants, respectively. For the case of extreme and maximum confinement, 0.5 < H − 1 < 1 and H − 1 = 1 , respectively, analytical results can be given based on an extension for quantum systems of the Helmholtz free energies for the corresponding classical systems. [ABSTRACT FROM AUTHOR]

The Patagonian fjords are high-latitude aquatic ecosystems, highly sensitive to climate change and play a key role in the exchange of organic matter and carbon flows between terrestrial and marine environments. The bioenergetic composition of species living in these ecosystems are fundamental to understanding the distribution, seasonal variations, and exchange of organic matter within benthic communities. This study reports on the bioenergetic characteristics (lipids, protein, glucose, and energy content) of three keystone species with different life-style and feeding habits: a benthic sea star (Ctenodiscus australis); squat lobster (Munida gregaria); and a Patagonian notothenioid (Eleginops maclovinus). Samples were obtained from the Yendegaia Fjord (54°40'S - 68°50′W) in Chilean Patagonia. Our results indicate that M. gregaria has higher concentrations of lipids, proteins, glucose, and total energy compared to either E. maclovinus or C. australis. The predominance of lipids in all species is possibly related to physiological characteristics and feeding strategies. Also, may be associated with the availability of food and environmental conditions typical of a fjord ecosystem and the reproductive stage in that they were collected. These results suggest that marine animals inhabiting glacially influenced environments with low temperature and low productivity, requires a convergent physiological strategy characterized by high levels of energy storage (i.e. lipids) for metabolism and key bioenergetic processes such as growth and reproduction. • The biochemical contents and energy may be attributed to the physiological characteristics and feeding strategies. • These results detail the biochemical composition of species of different trophic levels living in pristine Patagonian fjord. • The biochemical composition of a prey organism is an important measure as food for higher trophic levels. • Inhabiting glacially with low temperature and low productivity, requires a bioenergetic strategy of high energy storage. [ABSTRACT FROM AUTHOR]

• A holistic probabilistic multi-objective microgrid planning methodology. • Planning of MV networked microgrid with capacity of providing ancillary services. • Sizing and placing of DERs together cluster-based topology planning. • A true-multi-objective approach offers multiple Pareto solutions for decision-making. • A more holistic microgrid planning methodology is necessary to exploit its benefits. Microgrids have attracted the attention of researchers and stakeholders because of their well-known impacts and related benefits. Especially the provision of ancillary services has drawn attention. However, traditional planning should be re-defined to optimally achieve such promising advantages, which leads to a complex decision-making problem that should be progressively addressed with a more modern and comprehensive holistic approach. Hence, this paper proposes an enhanced version of the probabilistic multi-objective microgrid planning methodology (POMMP2) that includes a novel strategy to apply graph partitioning and metaheuristic optimization to consider simultaneously the planning of a cluster-based topology with the size and location of distributed energy resources under the paradigm of a microgrid with capacity for providing ancillary services. POMMP2 is tested in an adapted IEEE-37 node system, and NSGAII and AHP are used as optimization and decision-making algorithms, respectively. Results show the benefits of a planning methodology viewed as a comprehensive problem and not a set of independent tasks. [ABSTRACT FROM AUTHOR]

• In general, no linear relationship between leaf waxes and elevation is observed. • Chusquea sp. n -alkanoic acid abundance is correlated with precipitation and aridity. • A. araucana n -alkane ACL and abundance are correlated with temperature. • High relative abundance of n -alkanoic acids (>60%) in the three plant species. • Different abundance and ACL among species in both n -alkanes and n -alkanols. The n -alkyl leaf waxes of the temperate forest of South America are poorly studied, despite being a biogeographically isolated forest spanning wide environmental conditions. To evaluate whether local species adaptation and environmental changes influence the n -alkyl leaf wax composition, we measured the molecular abundance and distribution of n -alkyl leaf waxes (n -alkanoic acids, n -alkanes and n- alkanols) of three dominant native species from southern temperate forest in South America. We surveyed Araucaria araucana (n = 9), Nothofagus dombeyi (n = 17) and Chusquea sp. (n = 21) at different elevations. The relationship of n -alkyl leaf wax abundance and distribution with elevation is not significant in any species, except for n -alkane ACL (average chain length) in Chusquea sp. Significant correlations are found for n -alkanoic acid abundance with precipitation and aridity in Chusquea sp. and n -alkane abundance and ACL with temperature in A. araucana. These data suggest a species-specific response to environmental variables. The main similarity in the three species is a higher abundance of n -alkanoic acids (>60%) relative to other n -alkyl leaf waxes. Only n -alkanols are not correlated to any environmental variable, and neither ACL nor C max overlap among species. These results suggest n -alkanols as a potential chemotaxonomic indicator at a lower taxonomic level in the region. [ABSTRACT FROM AUTHOR]

Background: There are no published cases of tonic-clonic seizures and posterior bilateral blindness during pregnancy and Severe Acute Respiratory Syndrome (SARS) Coronavirus (COV) 2 (SARS-COV-2) infection. We do not just face new and unknown manifestations, but also how different patient groups are affected by SARS-COV-2 infection, such as pregnant women. Coronavirus Disease 2019 (COVID-19), preeclampsia, eclampsia and posterior reversible leukoencephalopathy share endothelium damage and similar pathophysiology.Case Presentation: A 35-year-old pregnant woman was admitted for tonic-clonic seizures and SARS-COV-2 infection. She had a normal pregnancy control and no other symptoms before tonic-clonic seizures development. After a Caesarean section (C-section) she developed high blood pressure, and we initiated antihypertensive treatment with labetalol, amlodipine and captopril. Few hours later she developed symptoms of cortical blindness that resolved in 72 h with normal brain computed tomography (CT) angiography.Conclusion: The authors conclude that SARS COV-2 infection could promote brain endothelial damage and facilitate neurological complications during pregnancy. [ABSTRACT FROM AUTHOR]