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Adult neurogenesis is a unique form of neuronal plasticity in which newly generated neurons are integrated into the adult dentate gyrus in a process that is modulated by environmental stimuli. Adult-born neurons can contribute to spatial memory, but it is unknown whether they alter neural representations of space in the hippocampus. Using in vivo two-photon calcium imaging, we find that male and female mice previously housed in an enriched environment, which triggers an increase in neurogenesis, have increased spatial information encoding in the dentate gyrus. Ablating adult neurogenesis blocks the effect of enrichment and lowers spatial information, as does the chemogenetic silencing of adult-born neurons. Both ablating neurogenesis and silencing adult-born neurons decreases the calcium activity of dentate gyrus neurons, resulting in a decreased amplitude of place-specific responses. These findings are in contrast with previous studies that suggested a predominantly inhibitory action for adult-born neurons. We propose that adult neurogenesis improves representations of space by increasing the gain of dentate gyrus neurons and thereby improving their ability to tune to spatial features. This mechanism may mediate the beneficial effects of environmental enrichment on spatial learning and memory. Adult neurogenesis is a unique form of neuronal plasticity, involving the genesis and integration of newborn neurons into the mouse dentate gyrus. Here the authors demonstrate that adult neurogenesis improves representations of space in the dentate gyrus by increasing the place-specific responses of mature neurons. [ABSTRACT FROM AUTHOR]

Purpose: To demonstrate how the use of adjunctive Computed Tomography (CT) can modify diagnosis, treatment options, and operative planning of ankle fractures in comparison with conventional radiographs (CR) in isolation. Materials and methods: A total of 53 patients diagnosed with an ankle fracture between 2011 and 2016, were assessed with CT and CR. Evaluations of the fractures using CR in isolation and CR combined with CT were compared using different readers. Fractures were assessed in terms of type, displacement, size, associated injuries, treatment, patient position and surgical planning. Results: The medial malleolus fractures characteristics (posteromedial fragment and anterior colliculus), the presence of posterior malleolus fracture and its characteristics (displacement, size, posteromedial or posterolateral segment) (ps < 0.042), syndesmosis injury (p < 0.001), and the absence of deltoid ligament lesion (p < 0.001), were more evident with the combination of CT and radiographs. There was an increase in operative indication (p = 0.007), prone positioning (p = 0.002), posterior malleolus surgical treatment (p < 0.001), posterolateral approach for the lateral malleolus (p = 0.003), and syndesmosis fixation (p = 0.020) with the association of CT and CR, among all groups of expertise, with a high interobserver reliability (> 0.75). Conclusions: The CR may fail to demonstrate subtle lesions, such as posterior malleolus fractures and syndesmotic injuries. The CT evaluation increases the diagnostic precision and improves the quality of information the surgeon receives, what might positively affect patient care. Level of evidence III: Retrospective Comparative Study. [ABSTRACT FROM AUTHOR]

Conventional sewage treatment plants aim to minimize environmental impacts, but generate by-products, such as sludge, which also must be properly treated and dewatered. From the resource recovery perspective, a promising alternative is a reuse as fertilizer in agriculture, due to the nutrients in its composition, but the feasibility of this reuse depends on sludge treatment technologies that, in addition to promoting dewatering, treat toxic pollutants, pathogens and metals. Many techniques have been employed in an attempt to promote effective dewatering and remove pollutants from sludge, but the high cost of physicochemical treatments and risk of causing secondary pollution, make it difficult to apply on a larger scale, as well as reuse the sludge. Therefore, biological treatments, such as bioleaching, have become an increasingly popular choice, as they have economic and environmental benefits, which with improvements can enable the use of sludge as a resource. The objective of the present study was to investigate the scientific production of the last twelve years, regarding the microbiology of extracellular polymeric substances influence on sewage sludge dewatering during the bioleaching process. The specific objectives were to elucidate the influence of extracellular polymeric substances fractions on sludge dewatering, to identify the main microorganisms involved in extracellular polymeric substances generation and identify the main microorganisms involved in its removal during bioleaching. This literature review will help to understand the microbiological aspects of dewatering during the bioleaching process and will provide useful information to improve future research on the application of bioleaching in sewage sludge treatment. [ABSTRACT FROM AUTHOR]

Although it is considered an economically relevant and prevalent disease, little information is available on the epidemiology and risk factors of porcine proliferative enteropathy (PPE) in commercial pigs, and no publication is available on subsistence pig farming. The objectives of this study were to estimate the seroprevalence of L. intracellularis and identify associated risk factors in backyard pigs in the 12 mesoregions of the state of Minas Gerais, Brazil. Blood from pigs between 2 months and 6 years of age were sampled; an epidemiological questionnaire was applied to 288 properties investigated in 2016. Serum samples were tested for the presence of anti-L. intracellularis antibodies using an immunoperoxidase monolayer assay. The seroprevalence of L. intracellularis was 97.7% (CI 95%: 96.7–98.4), and there was no statistical difference among the prevalence of the sampled mesoregions. Only 3 of the 12 risk factors were significant when samples were analyzed from strongly seropositive animals (≥ 1:120) in a Poisson multivariate regression model. There was an interaction between properties in peri-urban areas and extensive production systems. This interaction demonstrated an increase in prevalence rates by 3.7 times (95%CI: 2.4–5.8). Properties close to dumps demonstrated an increase in prevalence rates by 2.2 times (95%CI: 0.99–4.8). In conclusion, anti-L. intracellularis antibodies were widely dispersed in subsistence pig farming’s in Minas Gerais, indicating a wide circulation of the agent in this type of production system. The interactions of animals raised close to peri-urban areas, extensively, and close to landfills are risk factors for spread of PPE. [ABSTRACT FROM AUTHOR]

Lead halide perovskites CsPbX 3 are still being promoted as photovoltaic materials and much attention is now drawn towards this class of alloys in spite of their long-term instability and the lead toxicity. Our work aims to investigate the substitution of Pb by Sn or Ge. The structural, optical, and electronic properties of the perovskites CsBX 3 (B = Pb, Sn, Ge; X = Cl, Br, I) are analyzed using density functional theory (DFT) through the software package Quantum ESPRESSO. The obtained optical and electronic properties are discussed as a function of the electronegativity of the B and X elements. The electronic study indicates that all these alloys are semiconductors with a direct band gap and reveals the dependence of the electronic band gap upon the nature of the cation B and the halogen X, which makes it easily adjustable by changing the B and/or X elements. Within the visible domain, the highest values of the dielectric constant, refractive index, and photoconductivity are obtained for the Ge halides. However, the lowest reflection and extinction coefficients are obtained for the Pb halides. In addition, the Ge halides are characterized by a wide absorption range from the infrared to the ultraviolet. The maximum absorption spectra are obtained for the chloride halides CsBCl 3 . These results shed some light on how to combine the positive characteristics of Pb and Ge halides to bring new possibilities of obtaining the best candidate for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Background: Qualitative research investigating pharmacists' participation in Long-Term Care (LTC) within interdisciplinary teams is scarce. Aim: To characterize how pharmacists' participation in a national network of LTC is perceived by healthcare professionals and other key stakeholders. Method: Individual, in-depth, semi-structured interviews of participants (nurses, physicians, pharmacists, and LTC researchers) enrolled purposively or through snowballing sampling techniques, with the final sample being comprised of fourteen participants. Data analysis followed a deductive coding approach framed by Role Theory and supplemented with an inductive coding for additional themes. Results: Four Role Theory constructs were identified from the primary data—role identity, overqualification, ambiguity, underqualification. Clinical pharmacy services, logistics and educational activities were pointed out as representing the identity of pharmacists' interventions. Despite the clear identification of LTC pharmacists' interventions, pharmacist expertise on medicine optimization seemed to be underused (role overqualification), as a result of lack of time, lower proactivity in healthcare teams' integration, and the absence of a legal framework targeted to LTC pharmacy practice (role ambiguity). Additional clinical training, including in the management of older people's health conditions, nutrition, and palliative care were missing (role underqualification). Conclusion: LTC pharmacists can provide essential services (e.g., clinical pharmacy, logistics, educational interventions), although additional training and a clearer legal framework are missing to better define pharmacists' roles in LTC pharmacy practice. [ABSTRACT FROM AUTHOR]

In this paper, f (R , T , R μ ν T μ ν ) gravity is considered. It is a modified theory of gravity that exhibits a strong coupling of gravitational and matter fields. Therefore, if gravity is governed by this model a number of issues must be re-examined. In this context, the question of causality and its violation is studied. Such analysis is carried out using the Gödel-type solutions. It is shown that this model allows both causal and non-causal solutions. These solutions depend directly on the content of matter present in the universe. For the non-causal solution, a critical radius is calculated, beyond which causality is violated. Taking different matter contents, an infinite critical radius emerges that leads to a causal solution. In this causal solution, a natural relationship emerges between the parameters that determine the matter considered. [ABSTRACT FROM AUTHOR]

Periodic bathymetry surveys are essential to provide data to keep navigation charts updated, obtain insights into water body bottom dynamics and processes, and for hydrodynamic modelling. Frequent bathymetry monitoring has become particularly important in a time of climate variability, which may affect hydrodynamics in yet unknown ways. Bathymetric data are, however, often scarce, because surveys are generally time consuming, expensive and complicated. A methodology combining a low-cost single beam sonar with a dual-frequency differential high-precision GNSS (Global Navigation Satellite System) is presented. Sonar depth measurements and GNSS positions were integrated optimizing sonar and GNSS track overlay. As a result, no physical, electronic link between both devices is needed, and precise positions and depths can be obtained without the need to apply the approach based on tide correction, which always introduces some uncertainty. The methodology was successfully tested and validated, with data collected inside an estuary and offshore the estuarine inlet. Vertical accuracies, assessed at track crossings and on locations of known depths, showed mean squared errors of about 20 cm, suggesting that the method is reliable in providing bathymetric data that satisfy the highest standards of the IHO for hydrographic surveys. Validation results suggest that the effects of boat pitch, roll and yaw on depth measurements were negligible in our survey, which covered depths between 0.4 and 24.5 m below MSL and were carried out in quite calm waters, though larger errors occurred in the off-shore zone. The use of an inertial measurement unit (IMU), which can easily be coupled with the GNSS to extract ship motion data and correct depths accordingly, is advised for less optimal survey conditions and deeper waters. The proposed method is accurate, simple and affordable, allowing for more frequent surveys and a better coverage of dynamic shallow water systems such as rivers and estuaries. [ABSTRACT FROM AUTHOR]

We examined the interaction between adatoms and graphene for Ag, Cd, In and Hg by density functional theory. We establish a relation between the binding energy and the electric-field gradient tensor (EFG) for each atom, which indicates that hyperfine interactions can be used to probe the binding and stability of adatoms on graphene. The EFG is also shown to be a fingerprint for the local configuration, even at the sub-Angstrom scale. This work demonstrates how suitable hyperfine methods, such as perturbed angular correlation spectroscopy, can be used to experimentally unravel details of atomic adsorption on graphene, and by extension on two-dimensional materials in general. [ABSTRACT FROM AUTHOR]

Aims: Belowground interactions are still poorly understood in mixed-species forests. We investigated the effects of soil fertility on belowground processes in mixed planted forests. Methods: The dynamics and traits of Eucalyptus and Acacia mangium fine roots (diameter < 2 mm) in plantations with 50% of each species were studied in a randomized block design established in a nutrient depleted soil. Stands with NPK fertilization applied at planting (F+) were compared to unfertilized stands (F-). Results: In the 0–15 cm soil layer, Eucalyptus root mass density (RMD) was higher than Acacia RMD by 50% in F+ and 10% in F-, considering both ages. At 34 months of age, Eucalyptus RMD was 94% higher near Acacia trees than near Eucalyptus trees in F-. In this layer, Eucalyptus specific root length (SRL) was 21% higher than Acacia SRL at 16 months of age and was 10% higher in F- than in F+ at 34 months of age. The cumulative Eucalyptus fine root length production between 16 and 34 months was 66% higher in F- than in F+ in the 0–1 m soil layer. Conclusions: Fertilization increased the competition between species and led to a partial exclusion of Acacia fine roots from the nutrient-rich topsoil. Soil exploration by Eucalyptus roots in the vicinity of Acacia trees was higher in F- than in F+, which suggests that unfertilized trees benefited from facilitation through higher soil N availability and direct N transfer from Acacia trees. [ABSTRACT FROM AUTHOR]

Melanoma is a form of skin cancer with high mortality owing to its fast progression and metastatic capacity. The treatments available nowadays are only palliative in advanced stages of the disease. Thus, alternative therapies for cancer treatment are in demand, and molecules from natural sources, such as polysaccharides, could represent new possible therapeutic approaches. Polysaccharides of freshwater and marine algae with biological activities, such as antitumor properties, are greatly reported in the scientific literature. In the present study, a sulfated heterorhamnan obtained from the green seaweed Gayralia brasiliensis (Gb1 fraction) was chemically characterized and its biological activities in the B16-F10 murine melanoma cell line were evaluated. The Gb1 polysaccharidic fraction tested concentrations presented low or absence of cytotoxicity to B16-F10 cells and neither cell proliferation nor cell cycle were altered. Interestingly, Gb1 treatment decreased B16-F10 cells migration and invasion capabilities and CD44 labeling, showing to be a promising compound for further in vitro and in vivo antitumor studies. [ABSTRACT FROM AUTHOR]

It is established existence, multiplicity, and asymptotic behavior of nonnegative solutions for a quasilinear elliptic problem driven by the Φ -Laplacian operator. One of these solutions is obtained as ground-state solution by applying the well-known Nehari method. The nonlinear term is a concave–convex function which presents a critical behavior at infinity. The concentration-compactness principle is used in order to recover the compactness required in variational methods. [ABSTRACT FROM AUTHOR]

Bifurcaria bifurcata is a seaweed of the Order Fucales (Ochrophyta, Phaeophyceae) that can be found all year round along the Portuguese Atlantic shore. Although it is considered edible in some countries, its biotechnological potential has not yet been assessed in detail and here we report its antimicrobial potential against human dermatophyte fungi. Three samples were harvested from Baleal Island (Peniche, Portugal) harvested in winter (BbPe); from Aguda Beach (Arcozelo, Vila Nova de Gaia, Portugal), harvested in autumn (BbAg) and a sample obtained by culturing the Aguda sample under laboratory conditions (BbLC). A broth macrodilution assay was applied to determine the MIC (minimum inhibitory concentration) and MLC (minimum lethal concentration) of the B. bifurcata extracts. Results show that the BbPe MeOH extracts were the most effective and had higher antifungal activity against all the tested dermatophyte strains than the BbLC and BaAg extracts [Epidermophyton floccosum FF9 (100–200 µg/mL MIC; 200 µg/mL MLC), Microsporum canis FF1 (400 µg/mL MIC; ≥400 µg/mL MLC), Trichophyton mentagrophytes FF7 (100 µg/mL MIC; >800 µg/mL MLC), M. gypseum CECT 2908 (800 µg/mL MIC; ≥800 µg/mL MLC), T. mentagrophytes var. interdigitale CECT 2958 (800 µg/mL MIC; ≥800 ug/mL MLC), T. rubrum CECT 2794 (200 µg/mL MIC; ≤400 µg/mL MLC)]. In fact, only E. floccosum FF9 was sensitive to BbAg and BbLC MeOH extracts. To our knowledge, this is the first report of antifungal activity of B. bifurcata against human dermatophyte fungi. [ABSTRACT FROM AUTHOR]

The invertebrate biodiversity of subtropical streams depends on the seasonal input of organic matter, as much as the leaf decomposition process on stream system. However, one of the challenges in determining the importance of invertebrates for leaf breakdown in subtropical streams is the low taxonomic resolution applied in most studies. To overcome this limitation, here we used litter bags with senescent leaves to evaluate the impact of different taxonomic resolutions of trophic group classification to assess the seasonal importance of invertebrate community for leaf litter breakdown in a subtropical stream (Atlantic Forest in western of Paraná state, Brazil). Litterfall was quarterly measured over a year. The leaf litter accumulated in an interval of 30 days was retrieved, weighed, and used for the leaf breakdown experiments (by litter bags). We found a lower importance of invertebrate community richness and density (shredders and scrapers) in leaf breakdown process irrespective of the taxonomic resolution (family or genus level used). Hyphomycetes biomass and fungi sporulation also did not present changes among sample times, and consecutively, importance for leaf breakdown. However, the richness and density of Chironomidae taxa respond differently depending on the taxonomic resolution used. Low litter breakdown may be explained by the increase of consumption of microorganisms, due to high density of Chironomidae scrapers evaluated at the genus level. Moreover, temperature is the main factor responsible for breakdown over the year, in a positive way. Therefore, our results indicated the family level as the taxonomic resolution sufficient to assess the role of shredders and scrapers in the leaf litter breakdown process of this subtropical stream system. [ABSTRACT FROM AUTHOR]

The knowledge of the decomposition of macrophytes and associated organisms is important to understand ecological processes that control aquatic ecosystem metabolism. The aims of the study were: 1) to investigate the structure and composition of the aquatic invertebrate community associated with the decomposition of leaves of the macrophyte Eichhornia azurea over time; 2) to determine the biomass of microorganisms (fungi and bacteria) and their relationship with the associated invertebrate communities; and 3) to assess the relationship between biotic and abiotic variables and invertebrate density. To analyze the decomposition process, leaves of E. azurea were put into litter bags and incubated in Barbosa Lake, São Paulo State, Brazil. Litter bags were retrieved at seven sampling occasions during a 2.5 month period. We measured decomposition rates of leaves, and the associated communities of invertebrates, the biomass of bacteria and fungi, and biotic and abiotic variables that might be associated with the decomposition process. Significant differences were found in the densities of invertebrates. The microorganism biomass also varied significantly throughout the experiment. Fungal biomass (ergosterol concentration) was positively associated with the density of most taxonomic groups of aquatic invertebrates, as well as the total density of invertebrates and their taxonomic richness. Total invertebrate density increased during the experiment, but the taxonomic richness of invertebrates did not follow this pattern. Insecta and Crustacea densities were the main contributors to similarity within the groups formed at each sampling time. The different ways that invertebrates use detritus, such as a food source or a feeding site, as well as their feeding plasticity, may have contributed to the increase in the total invertebrate density over time as decomposition progressed. After two months and a half of macrophyte incubation the loss of E. azurea leaf biomass was less than 4.4% of the initial value. Factors such as decreasing temperature throughout the experiment, possible inhibition of microorganism growth by leachates, the predominantly oligotrophic environment and low abrasion due to the environment lentic regime may have contributed to the low rate of decomposition of E. azurea. Our results suggest that decomposition process in the present study has not begun in fact and/or macrophyte decomposition in nature is much slower than previously thought. [ABSTRACT FROM AUTHOR]

Differentiation of human pluripotent stem cells to small brain-like structures known as brain organoids offers an unprecedented opportunity to model human brain development and disease. To provide a vascularized and functional in vivo model of brain organoids, we established a method for transplanting human brain organoids into the adult mouse brain. Organoid grafts showed progressive neuronal differentiation and maturation, gliogenesis, integration of microglia, and growth of axons to multiple regions of the host brain. In vivo two-photon imaging demonstrated functional neuronal networks and blood vessels in the grafts. Finally, in vivo extracellular recording combined with optogenetics revealed intragraft neuronal activity and suggested graft-to-host functional synaptic connectivity. This combination of human neural organoids and an in vivo physiological environment in the animal brain may facilitate disease modeling under physiological conditions. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to investigate the association between the videofluoroscopic (VFS) signs of impaired efficacy (pharyngeal residue) and safety (aspiration) swallowing and the clinical/nutritional status of patients with suspect of dysphagia. Design: A cross-sectional study was conducted with patients submitted to videofluoroscopy. Setting and Participants: Data of 76 patients were analyzed between March 2011 and December 2014. Measurements: The clinical history and VFS exams of patients ≥ 38 years were retrospectively analyzed. Results: 88% patients presented Oropharyngeal Dysphagia (OD), 44.7% presented laryngeal penetration and 32% presented aspiration. 78% patients presented pharyngeal residue. Aspiration was associated with Head Neck Cancer (HNC) [Prevalence Ratio (PR): 2.27, p = 0.028] and cardiovascular disease (PR 1.96, p = 0.027). Underweight [Body Mass Index < 18.5 kg/m] was not associated with the presence of aspiration. Underweight patients with OD had a higher prevalence rate of pharyngeal residue than those normally nourished (100% vs. 78%) (PR 1.34, p = 0.011). Pharyngeal residue was associated with male sex (PR 1.32, p = 0.040), neurodegenerative disease (PR 1.57, p = 0.021), stroke (PR 1.62, p = 0.009), cerebral palsy (PR 1.76, p = 0.006) and HNC (PR 1.73, p = 0.002). Conclusion: In the present study, neurologic diseases, HNC, male sex and underweight were associated to impaired swallowing efficacy. Underweight, independently of the other variables, was not associated with impaired swallowing safety. [ABSTRACT FROM AUTHOR]

The training of medical students demands practice of skills in scenarios as close as possible to real ones that on one hand ensure acquisition of competencies, and on the other, avoid putting patients at risk. This study shows the practicality of using high definition mannequins (SimMan 3G) in scenarios of first attention in neurological emergencies so that medical students at the Faculty of Medicine of the University of Salamanca could acquire specific and transversal competencies. The repetition of activities in simulation environments significantly facilitates the acquisition of competencies by groups of students ( p < 00.5). The greatest achievements refer to skills whereas the competencies that demand greater integration of knowledge seem to need more time or new sessions. This is what happens with the competencies related to the initial diagnosis, the requesting of tests and therapeutic approaches, which demand greater theoretical knowledge. [ABSTRACT FROM AUTHOR]

Particle deposition in the human lungs is mainly influenced by the fluid dynamics and the particle properties, such as the size and the deposition mechanisms. A three-dimensional gas particle flow model to predict particle deposition and flow patterns in four generations of the human lung, located in the bronchial region, is presented in this paper. Four breathing conditions (sleep, resting, moderate activity, and intense activity) were simulated, using the commercial code ANSYS Fluent version 14.5. The particle diameter was varied from 1 to 10 μm. The results showed that deposition in each of the three bifurcations was not uniform and should be analyzed separately based on particle diameter. The influence of gravitational settling and Brownian diffusion on particle deposition was also investigated and quantified. The greater difference in the deposition between cases considering these physical mechanisms and not considering it occurred in situations involving lower velocity, showing a value of 172 % for gravitational settling mechanism and a difference of 11 % for Brownian diffusion. Furthermore, it was observed that the total deposition increased with the Reynolds and Stokes numbers, suggesting that exercise practices should be avoided in situations with high levels of suspended particulate matter. [ABSTRACT FROM AUTHOR]

Groundwater pollution is a major environmental concern at global scale. It usually restricts the use of water resources for domestic, agricultural or industrial purposes, with significant impact on human well-being. Aquifer remediation may be very difficult or even impossible due to technical and/or economic constraints. To help prevent groundwater pollution, several cartographic methods have already been developed. Geographical information systems (GIS) provide useful tools for understanding the spatial distribution of groundwater vulnerability to pollution. This paper presents a new tool to produce groundwater vulnerability to pollution maps under a GIS open source environment. This application was developed within the QGIS software. The tool determines the spatial distribution of the DRASTIC index and incorporates all the procedures required under a single plugin. One of the main advantages of this application is the easiness to use and the possibility of viewing different results modifying indexes, weight values and table descriptions or importing the input data attribute file description. The user can also generate the maps according to his perception regarding each aquifer system. This application is free and presents a valuable contribution to assess and map groundwater vulnerability to pollution through a GIS open source. [ABSTRACT FROM AUTHOR]

The temporal dynamics of leaf decomposition in a tropical stream were evaluated by measuring the input of leaves from riparian vegetation. The resulting mixture of leaves was processed by decomposer microorganisms and, in particular, by aquatic hyphomycetes, the most important microorganisms associated with leaf litter decomposition. Leaf decomposition and the characteristics and activity of the microbial community were investigated over the course of 1 year; these parameters depended on the composition and availability of leaves in the stream. We assessed the biomass, activity, and community structure of the fungi associated with the decomposing leaf mixtures monthly in a tropical stream with little seasonal variation in water characteristics. The leaf material included 27 riparian species; the amount of leaves of each contributing species varied from month to month, with higher overall values in the rainy season. Leaf decomposition was slow, and leaf mass loss did not occur monthly; however, leaf mass loss was significantly lower in May and September. The values of ATP, the ergosterol concentration, and the sporulation of aquatic hyphomycetes varied during the experiment, and only the ergosterol concentration (fungal biomass) was correlated with leaf mass loss. The sporulation rates of aquatic hyphomycetes peaked at the beginning of the rainy season (October), when only three hyphomycete species were present out of the total of seven that were found during the year. In this tropical stream, where the physical and chemical characteristics of the stream water varied little during the year, we hypothesize that changes related to leaf chemical composition could be the cause of changes in decomposition and the abundance and composition of the fungal assemblages. No significant differences were found for the parameters analyzed (lignin, cellulose, fiber, phosphorous, and polyphenols). [ABSTRACT FROM AUTHOR]

Nat. Biotechnol. 36, 432–441 (2018); published online 16 April 2018; corrected after print 18 July 2018 In the version of this article initially published, credit for part of Figure 4a was omitted. The image of a lens and microscope stage was originally published elsewhere. The error has been corrected in the HTML and PDF versions of the article. [ABSTRACT FROM AUTHOR]

A Mobile Mapping System (MMS) is composed by a set of sensors placed on a mobile platform whose main objective is to obtain attitude and position over time of a referential in the platform together with the image of the objects surrounding the platform. The acquired data allows to obtain georeferenced positions of object points captured by the object sensors. This paper describes a methodology to automatically extract accurate Digital Terrain Models (DTM) of sand beach areas using a Terrestrial Mobile Mapping System (TMMS). The main goal of the presented TMMS is to obtain accurate 3D models of sand beaches. A very important consequence of this will be the abbility to track spatial and temporal changes in coastal geomorphology. The presented methodology has several advantages over more classical approaches: the overall cost, flexibility for regular surveys or at the most convenient epoch, such as after storms. Besides one of the major constraints in Mobile Mapping, that is poor GNSS (Global Navigation Satellite Systems) observation conditions, is usually not present in these areas. The TMMS uses two progressive colour video cameras and can work with any type of direct georeferencing system, which obvoiusly has impact in the final accuracy of the derived DTM. For the results herein reported, a dual frequency GNSS receiver and a low grade type of IMU (Inertial Measurement System) were used. The moving platform where the system was installed is a moto quad. The developed methodology for the DTM generation relies on an automatic choice of terrain points whose three-dimensional coordinates are calculated using a presented image matching technique. A cloud of points obtained in a nearly regular grid pattern is the base for the DTM. The proposed methodology was applied on a sector of the Vila Nova de Gaia Coast, in northern Portugal, and the results presented here show that it is possible with this methodology to produce DTMs with a precision of a few centimetres. [ABSTRACT FROM AUTHOR]

Subtle alterations in how cortical network dynamics are modulated by different behavioral states could disrupt normal brain function and underlie symptoms of neuropsychiatric disorders, including Fragile X syndrome (FXS). Using two-photon calcium imaging and electrophysiology, we recorded spontaneous neuronal ensemble activity in mouse somatosensory cortex. Unanesthetized Fmr1−/− mice exhibited abnormally high synchrony of neocortical network activity, especially during the first two postnatal weeks. Neuronal firing rates were threefold higher in Fmr1−/− mice than in wild-type mice during whole-cell recordings manifesting Up/Down states (slow-wave sleep, quiet wakefulness), probably as a result of a higher firing probability during Up states. Combined electroencephalography and calcium imaging experiments confirmed that neurons in mutant mice had abnormally high firing and synchrony during sleep. We conclude that cortical networks in FXS are hyperexcitable in a brain state-dependent manner during a critical period for experience-dependent plasticity. These state-dependent network defects could explain the intellectual, sleep and sensory integration dysfunctions associated with FXS. [ABSTRACT FROM AUTHOR]

Increasing areas of Amazonian forest are coming under flood stress due to dam construction and greater variability in river flood levels due to climate change. The physiological responses of Amazonian trees subjected to flooding are important to understand the consequences of these changes. Irradiance response curves for photosynthesis obtained from ten tropical tree species growing in flooded areas were used to fit three empirical models. The study was done in floodplains along the Uatumã River, both upstream and downstream of the Balbina Hydroelectric Dam in Brazil's state of Amazonas (01°55′S; 59°28′W). Ten species were studied. Models compared were: non-rectangular hyperbola, rectangular hyperbola, and exponential. All models were quantitatively adequate for fitting the response of measured data on photosynthesis to irradiance for all ten species in the non-flooding and flooding periods. Considerable variation was found among the model estimates of maximum photosynthesis ( P), dark respiration ( R) and apparent quantum yield of photosynthesis (α). For photosynthesis, the two hyperbolas overestimated P while EXP presented more realistic values. For estimating R, RH presented the most realistic values. To avoid unrealistic value estimates of R, we recommend adding measured R values to the regressions. The results suggest that the EXP model presented the most realistic P and α values, and, in spite of less accuracy in fitting photosynthetic irradiance curves than the RH model, it can be recommended for accessing the information used in photosynthetic irradiance curves for the leaves of tropical trees growing in Amazonian floodplains or in areas that are artificially flooded by dams. [ABSTRACT FROM AUTHOR]

The biofilms formed by opportunistic yeasts serve as a persistent reservoir of infection and impair the treatment of fungal diseases. The aim of this study was to evaluate photodynamic inactivation (PDI) of biofilms formed by Candida spp. and the emerging pathogens Trichosporon mucoides and Kodamaea ohmeri by a cationic nanoemulsion of zinc 2,9,16,23-tetrakis(phenylthio)-29H,31H-phthalocyanine (ZnPc). Biofilms formed by yeasts after 48 h in the bottom of 96-well microtiter plates were treated with the photosensitizer (ZnPc) and a GaAlAs laser (26.3 J cm). The biofilm cells were scraped off the well wall, homogenized, and seeded onto Sabouraud dextrose agar plates that were then incubated at 37°C for 48 h. Efficient PDI of biofilms was verified by counting colony-forming units (CFU/ml), and the data were submitted to analysis of variance and the Tukey test ( p < 0.05). All biofilms studied were susceptible to PDI with statistically significant differences. The strains of Candida genus were more resistant to PDI than emerging pathogens T. mucoides and K. ohmeri. A mean reduction of 0.45 log was achieved for Candida spp. biofilms, and a reduction of 0.85 and 0.84, were achieved for biofilms formed by T. mucoides and K. ohmeri, respectively. Therefore, PDI by treatment with nanostructured formulations cationic zinc 2,9,16,23- tetrakis (phenylthio)- 29H, 31H- phthalocyanine (ZnPc) and a laser reduced the number of cells in the biofilms formed by strains of C. albicans and non- Candida albicans as well the emerging pathogens T. mucoides and K. ohmeri. [ABSTRACT FROM AUTHOR]

We present a simple but effective small unmanned aerial vehicle design that is able to make high-resolution temperature and humidity measurements of the atmospheric boundary layer. The air model used is an adapted commercial design, and is able to carry all the instrumentation (barometer, temperature and humidity sensor, and datalogger) required for such measurements. It is fitted with an autopilot that controls the plane's ascent and descent in a spiral to 1800 m above ground. We describe the results obtained on three different days when the plane, called Aerolemma-3, flew continuously throughout the day. Surface measurements of the sensible virtual heat flux made simultaneously allowed the calculation of all standard convective turbulence scales for the boundary layer, as well as a rigorous test of existing models for the entrainment flux at the top of the boundary layer, and for its growth. A novel approach to calculate the entrainment flux from the top-down, bottom-up model of Wynagaard and Brost is used. We also calculated temperature fluctuations by means of a spectral high-pass filter, and calculated their spectra. Although the time series are small, tapering proved ineffective in this case. The spectra from the untapered series displayed a consistent −5/3 behaviour, and from them it was possible to calculate a dimensionless dissipation function, which exhibited the expected similarity behaviour against boundary-layer bulk stability. The simplicity, ease of use and economy of such small aircraft make us optimistic about their usefulness in boundary-layer research. [ABSTRACT FROM AUTHOR]

Research on the importance of serum uric acid (SUA) as a contributing metabolic factor to cardiovascular diseases has conducted to conflicting results, with most studies assuming a cross-sectional design. The aim of this study was to evaluate the association of SUA and metabolic syndrome (MetS) and its features. A representative sample of 2,485 individuals aged ≥18 years was randomly selected from the non-institutionalized resident population of Porto, Portugal. A total of 1,054 eligible subjects were included for the longitudinal analyses. Hyperuricemia was defined as SUA ≥70 mg/L in men and ≥60 mg/L in women. MetS was defined according the Joint Interim (2009) criteria. Associations were estimated using Poison regression and binomial models. In the cross-sectional analysis, subjects with hyperuricemia had a 2.10-fold increased risk of MetS as compared with normouricemic subjects (PR = 2.10, 95% CI: 1.68-2.63). Among MetS features, high triglycerides presented the strongest association with hyperuricemia (PR = 2.32, 95% CI: 1.84-2.91). The MetS crude incidence rate was 4.5/100 person-year (95% CI: 3.9-5.2) in normal uricemic and 13.0/100 person-year (95% CI: 8.5-20.0) in hyperuricemic participants. Using a multivariate longitudinal approach, hyperuricemia was positively associated with MetS incidence rate ratios (IRR = 1.73, 95% CI: 1.08-2.76). One standard deviation increase of SUA concentration was associated with a 1.22-fold increase in MetS risk (IRR = 1.22, 95% CI: 1.05-1.42). Elevated SUA presented the strongest association with high-triglycerides concentration (IRR = 1.44, 95%: 1.22-1.71) and waist circumference (IRR = 1.25, 95%: 1.05-1.49). The independent positive association between SUA and MetS suggested by this longitudinal study supports that SUA might be a risk factor for MetS. [ABSTRACT FROM AUTHOR]

In vivo two-photon calcium imaging would benefit from the use of multiple excitation beams to increase scanning speed, signal-to-noise ratio and field of view or to image different axial planes simultaneously. Using spatiotemporal multiplexing we circumvented light-scattering ambiguity inherent to deep-tissue multifocal two-photon microscopy. We demonstrate calcium imaging at multiple axial planes in the intact mouse brain to monitor network activity of ensembles of cortical neurons in three spatial dimensions. [ABSTRACT FROM AUTHOR]

The Perturbed Angular Correlation (PAC) technique was applied to study the yttrium local environment in YMnO multiferroic manganite. The electric field gradients (EFG) at the Y site have been measured as function of temperature, covering both ferroelectric and magnetic transitions. The results were compared with point charge model (PCM) calculations. The experimental results show two different EFG distributions for all temperatures. Only one can be directly attributed to the yttrium crystalline site in the hexagonal structure. [ABSTRACT FROM AUTHOR]

When cement hydrated compositions are analyzed by usual initial mass basis TG curves to calculate mass losses, the higher is the amount of additive added or is the combined water content, the higher is the cement ‘dilution’ in the initial mass of the sample. In such cases, smaller mass changes in the different mass loss steps are obtained, due to the actual smaller content of cement in the initial mass compositions. To have a same mass basis of comparison, and to avoid erroneous results of initial components content there from, thermal analysis data and curves have to be transformed on cement calcined basis, i.e. on the basis of cement oxides mass present in the calcined samples or on the sample cement initial mass basis. The paper shows and discusses the fundamentals of these bases of calculation, with examples on free and combined water analysis, on calcium sulfate hydration during false cement set and on quantitative evaluation and comparison of pozzolanic materials activity. [ABSTRACT FROM AUTHOR]

This paper reports an experimental study on the magnesium sulphate resistance of mortar specimens incorporating 0, 10 and 20% of metakaolin (MK). The evidence of the attack was evaluated through the content of calcium hydroxide (portlandite) and formation of magnesium hydroxide (brucite) by thermal analysis (thermogravimetric and derivative thermogravimetric analysis). The mechanical degradation of the mortar specimens was evaluated through splitting tensile tests after 200 days of exposition to the magnesium solution. The addition of metakaolin resulted in a reduction in the content of calcium hydroxide and in a smaller formation of brucite in comparison with reference mixture. A tensile strength loss of about 7% was observed for the metakaolin mortars submitted to the magnesium solution attack for 200 days. [ABSTRACT FROM AUTHOR]

Floral nectar chemical composition of conventional and transgenic sweet orange trees expressing the antibacterial peptide sarcotoxin IA (Stx IA), which has been shown to efficiently inhibit in vitro growth of the bacteria responsible for citrus canker ( Xanthomonas axonopodis pv. citri), is reported. The nectar contents of primary metabolites (sugars, amino acids, proteins, triacylglycerides) and of the secondary metabolites (total purine alkaloids, phenolic compounds and phytosteroids) were determined by spectrophotometric analysis. The results showed small differences in the nectar primary and secondary metabolites composition. The biochemical and biological significance and the possible effects of these variations on key citrus pollinators are discussed. [ABSTRACT FROM AUTHOR]

The cement industry is one which most emits polluting gases to the environment, due to the calcium carbonate calcination, as well as to the burning of fossil fuels during the manufacturing process. Metakaolin (MK), in partial substitution to cement in its applications, is having a special worldwide growing role, for the technological increment due to its pozzolanic activity and mainly to the reduction of those emissions. In the present paper, the effect of pozzolanic activity of metakaolin was analyzed by thermal analysis in pastes and mortars of type II Portland cement in the first three days of the hydration, during which, relevant initial stages of the hydration process occur. By non-conventional differential thermal analysis (NCDTA), paste and mortar samples containing 0, 10, 20, 30 and 40% of metakaolin in cement mass substitution and using a 0.5 water/(total solids) mass ratio, were evaluated. The NCDTA curves, after normalization on cement mass basis and considering the heat capacity of each reactant, indicate that the pozzolanic activity behavior of metakaolin is different in pastes and mortars. Through the deconvolution of the normalized NCDTA curve peaks, it can be seen that ettringuite formation increases as cement substitution degree (CSD) increases, in both cases. Tobermorite formation is more enhanced in mortars than in pastes by MK, with a maximum formation at 30% of CSD. In the pastes, tobermorite formation increases as CSD increases but it is practically the same at 30 and 40% of CSD. [ABSTRACT FROM AUTHOR]

The standard ( p 0=0.1 MPa) molar enthalpies of formation, at T=298.15 K, in the gaseous phase, for three tetradentate Schiff bases involving a N2O2 set, N, N’-bis(salicylaldehydo)cyclohexanediimine (H2salch), N, N’-bis(acetylacetone)cyclohexanediimine (H2acacch) and N, N’-bis(benzoylacetone)cyclohexanediimine (H2bzacch), were determined from their enthalpies of combustion and sublimation, obtained by static bomb calorimetry in oxygen and by the Knudsen effusion technique, respectively. The results are compared with identical parameters for related compounds previously studied, resulting from the condensation of salicylaldehyde or β-diketone with aliphatic diamines. [ABSTRACT FROM AUTHOR]

Sufficient conditions for small time local transitivity and for the absence of local controllability of a generic dynamic inequality with locally bounded derivatives are presented. [ABSTRACT FROM AUTHOR]

Background. Endoscopic third ventriculostomy (ETV) has gained acceptance as the treatment of choice for noncommunicating hydrocephalus despite a relatively high failure rate and a higher surgical risk than the placement of a shunt. The benefits of shunt independence overcome both drawbacks. This argument also serves to consider candidates for ETV patients with a poor chance of success, a fact which may to a certain degree explain failure rates higher than 20% in most unselected series of patients with noncommunicating hydrocephalus.Method. From 1997 to 2003 sixty-six patients with suspected noncommunicating hydrocephalus were treated with ETV. Male and female patients were equally distributed. It is an adult-based series (median age 53 years). The etiology of hydrocephalus was a space-occupying lesion in 39 patients (59%) and primary aqueductal stenosis in 27 (41%). Forty-seven patients presented an acute form of hydrocephalus (71%), the remainder presented a chronic form of hydrocephalus. The morbidity and outcome of the procedure were reviewed. Criteria for success was shunt independence and failure was considered when any surgical manoeuvre was further required for the treatment of hydrocephalus. The outcome was evaluated using the Kaplan-Meier survival method.Findings. The probability of remaining with a functioning ETV at 5.7 years (mean follow-up period) is 71.6% (95% confidence interval: 60.5-82.8). Failure occurred in 18 patients (27.3%). If failure occurs, there is a cumulative probability of 90% (95% confidence interval: 84-97) that the failure declares itself during the first 16 days after surgery. There were transient complications in five patients (7.5%), permanent in one (1.5%) and no mortality related to the procedure.Conclusions. ETV had a 5-year success rate of 71.6% with a low rate of permanent complications. When ETV is successful, the result tends to hold up over time. Delayed failure is a rare event. [ABSTRACT FROM AUTHOR]

Let K[ G] denote the group algebra of the finite group G over the non-absolute field K of characteristic ≠ 2, and let *: K[ G] → K[ G] be the K-involution determined by g*= g −1 for all g ∈ G. In this paper, we study the group A = A( K[ G]) of unitary units of K[ G] and we classify those groups G for which A contains no nonabelian free group. If K is algebraically closed, then this problem can be effectively studied via the representation theory of K[ G]. However, for general fields, it is preferable to take an approach which avoids having to consider the division rings involved. Thus, we use a result of Tits to construct fairly concrete free generators in numerous crucial special cases. [ABSTRACT FROM AUTHOR]

We consider analytic Poisson tensors P whose associated Lie algebra at a singular point is resonant (in the sense of J. P. Dufour (J. Differential Geom. 30 (1990), 415–428)). We give sufficient conditions on the k-jet of P at the given point so that P is analytically linearizable. [ABSTRACT FROM AUTHOR]

Uncertainties in deviations of physical properties lead to a probabilistic failure analysis of the composite materials. The proposed optimization model for laminate composites is based on reliability analysis considering the ultimate failure state. To avoid difficulties associated with the complete analysis of the failure modes, bounds are established for the failure probability of the structural system. These bounds are related with the intact and degraded configurations of the structure. Using the first ply failure and the last ply failure theories and a degradation model for the mechanical properties with load sharing rules we obtain the failure probabilities corresponding to the two above configurations. The failure probability of each configuration is obtained using level 2 reliability analysis and the Lind-Hasofer method. The optimization algorithm is developed based on the problem decomposition into three subproblems having as objectives the maximization of the structural efficiency at intact and degraded configurations of the structure and weight minimization subjected to allowable values for the structural reliability. Additionally, the search for the initial design is performed introducing a weight minimization level. It is expected to explore the remaining load capacity of the structures after first ply failure as a function of the anisotropic properties of the composites. The design variables are the ply angles and the thicknesses of the laminates. The structural analysis for the model developed is performed through the finite element method mainly using the isoparametric degenerated shell finite element. The sensitivities are obtained using the discrete approach through the adjoint variable method. In order to show the performance of the analysis two examples are presented. [ABSTRACT FROM AUTHOR]

This study was undertaken in an attempt to explain why in some of the tissues in which noradrenaline and ATP act as co-transmitters the noradrenergic component predominates, while in others the predominant component is purinergic. Four different tissues were used: the epididymal portion of the rat vas deferens and the rabbit ear artery, tissues where the noradrenergic component predominates, and the prostatic portion of the rat vas deferens and the rabbit jejunal artery, where the purinergic component predominates. The noradrenaline content as well as the electrically-evoked release of noradrenaline were determined in all tissues. To determine the evoked release, the tissues were pretreated with pargyline (1 mmol · 1) and then exposed to H-noradrenaline, washed out and transmurally stimulated (1 Hz). In addition, the influence of inhibition of neuronal uptake by desipramine (40nmo1·1) on pre- and postjunctional effects of adrenaline and α-methylnoradrenaline (and/or noradrenaline) was compared. The noradrenaline content of the tissues averaged: 17.4, 23.2, 3.1, and 4.8 μg·g for the epididymal and the prostatic portions of the rat vas deferens and for the ear and the jejunal arteries of the rabbit, respectively. The fractional electrically-evoked release of H-noradrenaline was 2.02 and 2.04 × 10 for the epididymal and the prostatic portions of the rat vas deferens, respectively, and 3.33 and 3.26 × 10 for the ear and the jejunal arteries of the rabbit, respectively. Desipramine enhanced much more the postjunctional effect of noradrenaline, adrenaline, and α-methylnoradrenaline in the epididymal than in the prostatic portion of the rat vas deferens. Moreover, desipramine similarly enhanced the effects of noradrenaline and adrenaline in the ear artery, while it did not modify the responses to these amines in the jejunal artery. The influence of inhibition of neuronal uptake on the prejunctional effect of sympathomimetic agonists was studied in the rat vas deferens only. Desipramine caused very marked and similar enhancements of the inhibitory effect of the amines in the epididymal and the prostatic portions (72.5 and 93.5 times, respectively, for adrenaline, and 34.7 and 41.4 times, respectively, for α-methylnoradrenaline). These results are compatible with the hypothesis that postjunctional adrenoceptors are situated closer to the varicosities in the epididymal than in the prostatic portion of the rat vas deferens and also closer in the rabbit ear than in the rabbit jejunal artery. Therefore, the variation in the relative importance of the noradrenergic and the purinergic components may depend on the distance between the sites from where the transmitters are released and the sites where they act. [ABSTRACT FROM AUTHOR]

The present study was undertaken to compare the presynaptic interaction of neuronal noradrenaline uptake inhibitors with imidazoline and phenylethylamine αadrenoceptor agonists under two different conditions: at low and high noradrenaline concentrations in the biophase. Isolated mouse vasa deferentia were stimulated with trains of 7 pulses given at 0.2 Hz and the inhibition by the α-adrenoceptor agonists clonidine, α-methylnoradrenaline, and UK-14,304 of twitch responses was measured in the absence and in the presence of either cocaine (12 μmol/l) or desipramine (40 nmol/l). The effects were determined for the first (equivalent to single pulse stimulation) and the last stimulus of each train. Both uptake inhibitors antagonized the presynaptic inhibitory effects of imidazolines (clonidine and UK-14,304) on the last twitch; the effects on the first twitch remained unchanged. In contrast, the uptake inhibitors potentiated the inhibitory effect of the phenylethylamine (α-methylnoradrenaline) on both the first and the last twitches. These results support the view that the concentration of noradrenaline in the biophase plays a decisive role in the inhibition by a-adrenoceptor agonists of the electrically evoked release of noradrenaline. Agonists that are not substrates of neuronal uptake (i.e., clonidine, UK-14,304) become less effective when noradrenaline is present in the biophase while substrates of neuronal uptake (i. e., α-methylnoradrenaline) do not. The results argue against the hypothesis that uptake inhibitors interact directly with presynaptic α-adrenoceptors or act at some link between uptake and receptor sites. [ABSTRACT FROM AUTHOR]

This study examined the nature of α-adrenoceptor subtype involved in pressor responses to so-called selective α-adrenoceptor agonists after treatment with phenoxybenzamine in vivo. The influence of prazosin (0.1 mg/kg) and of yohimbine (1 mg/kg) on the dose-response curves for cirazoline in the pithed rat, and for phenylephrine in the anaesthetized dog were compared, after various doses of phenoxybenzamine. In the pithed rat, after 0.05 mg/kg phenoxybenzamine, prazosin caused a displacement of the dose-response curve of cirazoline to the right which was much larger than that caused by yohimbine; after 0.3 mg/kg phenoxybenzamine, prazosin and yohimbine caused about equal displacements; after 1 mg/kg phenoxybenzamine, yohimbine caused a marked displacement, while prazosin was without effect. In the anaesthetized dog, after 1 mg/kg phenoxybenzamine, prazosin and yohimbine produced about equal rightward shifts of the dose-response curve for phenylephrine. However, after 3 mg/kg phenoxybenzamine the rightward shift of the dose-response curve for phenylephrine was much larger after yohimbine than after prazosin. In the anaesthetized dog, verapamil (1 mg/kg) caused a small and parallel rightward shift of the dose-response curve for phenylephrine before phenoxybenzamine and a large and nonparallel one after phenoxybenzamine (3 mg/kg); the effect of verapamil on responses to the selective α-adrenoceptor agonist UK-14,304 (before and after phenoxybenzamine) were similar to those on responses to phenylephrine after phenoxybenzamine. It is concluded that after 1 mg/kg phenoxybenzamine in the pithed rat or after 3 mg/kg phenoxybenzamine in the anaesthetized dog, the responses to the so-called selective α-adrenoceptor agonists cirazoline and phenylephrine, respectively, are predominantly or totally α-adrenoceptor-mediated. This explains why, after inactivation of α-adrenoceptors by phenoxybenzamine, the so-called selective α- and α-adrenoceptor agonists are equally antagonized by calcium entry blockers. [ABSTRACT FROM AUTHOR]

Nat. Biotechnol. 36, 432–441 (2018); published online 16 April 2018; corrected after print 18 July 2018 In the version of this article initially published, credit for part of Figure 4a was omitted. The image of a lens and microscope stage was originally published elsewhere. The error has been corrected in the HTML and PDF versions of the article. [ABSTRACT FROM AUTHOR]

Soil erosion is a serious environmental problem. An estimation of the expected soil loss by water-caused erosion can be calculated considering the Revised Universal Soil Loss Equation (RUSLE). Geographical Information Systems (GIS) provide different tools to create categorical maps of soil erosion risk which help to study the risk assessment of soil loss. The objective of this study was to develop a GIS open source application (in QGIS), using the RUSLE methodology for estimating erosion rate at the watershed scale (desktop application) and provide the same application via web access (web application). The applications developed allow one to generate all the maps necessary to evaluate the soil erosion risk. Several libraries and algorithms from SEXTANTE were used to develop these applications. These applications were tested in Montalegre municipality (Portugal). The maps involved in RUSLE method—soil erosivity factor, soil erodibility factor, topographic factor, cover management factor, and support practices—were created. The estimated mean value of the soil loss obtained was 220 ton km−2 year−1 ranged from 0.27 to 1283 ton km−2 year−1. The results indicated that most of the study area (80 %) is characterized by very low soil erosion level (<321 ton km−2 year−1) and in 4 % of the studied area the soil erosion was higher than 962 ton km−2 year−1. It was also concluded that areas with high slope values and bare soil are related with high level of erosion and the higher the P and C values, the higher the soil erosion percentage. The RUSLE web and the desktop application are freely available. [ABSTRACT FROM AUTHOR]