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Valle Mandriole is one of the two last remaining freshwater wetlands in the coastal area of Ravenna (NE Italy). In 2011, a management technique that involves the complete drainage of the southern portion of Valle Mandriole during summer has been undertaken. In the present study, the effects of this artificial drying on the benthic macroinvertebrate fauna were assessed using a beyond before-after-control-impact (beyond BACI) sampling design. Macroinvertebrates dwelling on macrophytes and in bare sediments were sampled in the impact location and in four control locations, two times before and two times after the drying period. Simultaneously, water samples were collected to monitor chemical properties potentially affecting the studied organisms. Biological and chemical data were analysed by multivariate statistical methods. The statistical analysis did not detect any significant effect of the management action on the benthic macroinvertebrates or on the water chemical and physical properties. This contrasts with some previous results, suggesting that the effects of a management strategy based on draining completely dry and then reflooding a wetland area are site specific. However, it is necessary to consider that the present study does have some limitations, in particular, the differences between impact and control locations and the timing of the sampling. The highest biodiversity was observed in one small and isolated control location; this highlights how maintaining, protecting, restoring and even creating small ponds may play an important role in biodiversity conservation. [ABSTRACT FROM AUTHOR]

Today, most information sources provide factual, objective knowledge, but they fail to capture personalized contextual knowledge which could be used to enrich the available factual data and contribute to their interpretation, in the context of the knowledge of the user who queries the system. This would require a knowledge framework which can accommodate both objective data and semantic enrichments that capture user provided knowledge associated to the factual data in the database. Unfortunately, most conventional DBMSs lack the flexibilities necessary (a) to prevent the data and metadata, evolve quickly with changing application requirements and (b) to capture user-provided and/or crowdsourced data and knowledge for more effective decision support. In this paper, we present CrowdSourced Semantic Enrichment (CroSSE) knowledge framework which allows traditional databases and semantic enrichment modules to coexist. CroSSE provides a novel Semantically Enriched SQL (SESQL) language to enrich SQL queries with information from a knowledge base containing semantic annotations. We describe CroSSE and SESQL with examples taken from our SmartGround EU project. [ABSTRACT FROM AUTHOR]

Pharmaceuticals are widespread emerging contaminants and, like all pollutants, are present in combination with others in the ecosystems. The aim of the present work was to evaluate the toxic response of the crustacean Daphnia magna exposed to individual and combined pharmaceuticals. Fluoxetine, a selective serotonin re-uptake inhibitor widely prescribed as antidepressant, and propranolol, a non-selective β-adrenergic receptor-blocking agent used to treat hypertension, were tested. Several experimental trials of an acute immobilization test and a chronic reproduction test were performed. Single chemicals were first tested separately. Toxicity of binary mixtures was then assessed using a fixed ratio experimental design. Five concentrations and 5 percentages of each substance in the mixture (0, 25, 50, 75, and 100%) were tested. The MIXTOX model was applied to analyze the experimental results. This tool is a stepwise statistical procedure that evaluates if and how observed data deviate from a reference model, either concentration addition (CA) or independent action (IA), and provides significance testing for synergism, antagonism, or more complex interactions. Acute EC50 values ranged from 6.4 to 7.8 mg/L for propranolol and from 6.4 to 9.1 mg/L for fluoxetine. Chronic EC50 values ranged from 0.59 to 1.00 mg/L for propranolol and from 0.23 to 0.24 mg/L for fluoxetine. Results showed a significant antagonism between chemicals in both the acute and the chronic mixture tests when CA was adopted as the reference model, while absence of interactive effects when IA was used. [ABSTRACT FROM AUTHOR]

Currently, a noncomprehensive understanding of the physicochemical properties of carbon-based nanomaterial (CBNs), which may affect toxic effects, is still observable. In this study, an exploratory systematic investigation into the key physicochemical properties of multiwall carbon nanotube (MWCNT), single-wall carbon nanotube (SWCNT), and C-fullerene on their ecotoxicity has been undertaken. We undertook an extensive survey of the literature pertaining to the ecotoxicity of organism representative of the trophic level of algae, crustaceans, and fish. Based on this, a set of data reporting both the physicochemical properties of carbon-based nanomaterial and the observed toxic effect has been established. The relationship between physicochemical properties and observed toxic effect was investigated based on various statistical approaches. Specifically, analysis of variance by one-way ANOVA was used to assess the effect of categorical properties (use of a dispersant or treatments in the test medium, type of carbon-based nanomaterial, i.e., SWCNT, MWCNT, C-fullerene, functionalization), while multiple regression analysis was used to assess the effect of quantitative properties (i.e., diameter length of nanotubes, secondary size) on the toxicity values. The here described investigations revealed significant relationships among the physicochemical properties and observed toxic effects. The research was mainly affected by the low availability of data and also by the low variability of the studies collected. Overall, our results demonstrate that the here proposed and applied approach could have a major role in identifying the physicochemical properties of relevance for the toxicity of nanomaterial. However, the future success of the approach would require that the ENMs and the experimental conditions used in the toxicity studies are fully characterized. [ABSTRACT FROM AUTHOR]

Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of interannual-to-decadal temperature variability in the Northern Hemisphere during the past 2,500 years. Our results are based on new records of atmospheric aerosol loading developed from high-resolution, multi-parameter measurements from an array of Greenland and Antarctic ice cores as well as distinctive age markers to constrain chronologies. Overall, cooling was proportional to the magnitude of volcanic forcing and persisted for up to ten years after some of the largest eruptive episodes. Our revised timescale more firmly implicates volcanic eruptions as catalysts in the major sixth-century pandemics, famines, and socioeconomic disruptions in Eurasia and Mesoamerica while allowing multi-millennium quantification of climate response to volcanic forcing. [ABSTRACT FROM AUTHOR]

Recent studies suggest that the ecotoxicity of engineered nanoparticles (ENPs) is dependent upon the treatment of ENPs in suspensions (e.g. sonication or use of solvents) and on the mode of exposure to test organisms. We conducted several bioassays with Daphnia magna in order to determine how adverse effects of TiO nanoparticles (n-TiO) are influenced by experimental set-up. Several treatments were applied, including three test media, several treatments of n-TiO suspensions (stirring, sonication) and different exposure modes (exposure duration and volume of test suspension). No adverse effects were observed when D. magna were exposed to 50 mL of suspension, regardless of TiO concentration (up to 250 mg/L) and exposure duration. Conversely, adverse effects were observed when D. magna were exposed to 2 mL of suspension for 96 h with a 50 % effect concentration EC values ranging from 32 mg/L to 82 mg/L. Test media had no significant influence on the outcome of all treatments. For a better mechanistic understanding of the experimental set-up at which adverse effects were observed, the particle size of n-TiO in the test media was characterized throughout the test duration. These measurements revealed a fast and strong agglomeration with a secondary particle size in the order of magnitude of micrometers. Our study describes how the effects of n-TiO on D .magna are influenced by the duration of exposure and volume of media, highlighting the need for standardization of experimental methods. [ABSTRACT FROM AUTHOR]

Assessments of climate sensitivity to projected greenhouse gas concentrations underpin environmental policy decisions, with such assessments often based on model simulations of climate during recent centuries and millennia. These simulations depend critically on accurate records of past aerosol forcing from global-scale volcanic eruptions, reconstructed from measurements of sulphate deposition in ice cores. Non-uniform transport and deposition of volcanic fallout mean that multiple records from a wide array of ice cores must be combined to create accurate reconstructions. Here we re-evaluated the record of volcanic sulphate deposition using a much more extensive array of Antarctic ice cores. In our new reconstruction, many additional records have been added and dating of previously published records corrected through precise synchronization to the annually dated West Antarctic Ice Sheet Divide ice core, improving and extending the record throughout the Common Era. Whereas agreement with existing reconstructions is excellent after 1500, we found a substantially different history of volcanic aerosol deposition before 1500; for example, global aerosol forcing values from some of the largest eruptions (for example, 1257 and 1458) previously were overestimated by 20-30% and others underestimated by 20-50%. [ABSTRACT FROM AUTHOR]

Lactococcus lactis CRL 1584 isolated from a Lithobates catesbeianus hatchery inhibits the growth of Citrobacter freundii (a bullfrog pathogen) and Listeria monocytogenes by a synergistic effect between lactic acid, hydrogen peroxide and a bacteriocin-like molecule. The chemical characterization of the bacteriocin in cell-free supernatants indicates that it has a proteinaceous nature. Hexadecane and ethyl acetate did not modify the bacteriocin activity, while 10 and 20 % (v/v) chloroform decreased the activity by 29 and 43 %, respectively. The antimicrobial peptide was heat stable since 85 % of residual activity was detected when neutralized supernatants were heated at 80 °C for 30 min. Moreover, no bacteriocin inactivation was observed when supernatants were kept at −20 °C for 3 months. The synthesis of the bacteriocin was associated with bacterial growth, highest production (2,100 AU/ml) being detected at the end of the exponential growth phase. At pH ranges of 5-6.5 and 5.0-5.5 the inhibitory molecule was stable when stored for 2 days at 4 and 25 °C, respectively. Moreover, it had a bactericidal effect on L. monocytogenes and the ultrastructural studies of pathogenic cells revealed clumping of the cytoplasmic material, increased periplasmic space and cell wall modifications. The deduced amino acid sequence of the bacteriocin was identical to nisin Z and the genetic determinants for its production are harbored in the chromosome. These results, described for the first time in L. lactis from a bullfrog hatchery, will increase knowledge of the bacteriocin under study with a view to its potential inclusion in probiotics for raniculture or biopreservatives. [ABSTRACT FROM AUTHOR]

Water is well recognized as an important component in bone, typically regarded as a constituent of collagen, a pore-filling fluid in bone, and an adsorbed species on the surface of bone crystallites. The possible siting and role of water within the structure of the apatite crystallites have not been fully explored. In our experiments, carbonated hydroxyl- and fluorapatites were prepared in DO and characterized by elemental analysis, thermal gravimetric analysis, powder X-ray diffraction, and infrared and Raman spectroscopy. Two hydroxylapatites and two fluorapatites, with widely different amounts of carbonate were analyzed by solid state H NMR spectroscopy using the quadrupole echo pulse sequence, and each spectrum showed one single line as well as a low-intensity powder pattern. The relaxation time of 7.1 ms for 5.9 wt% carbonated hydroxylapatite indicates that the single line is likely due to rapid, high-symmetry jumps in translationally rigid DO molecules, indicative of structural incorporation within the lattice. Discrimination between structurally incorporated and adsorbed water is enhanced by the rapid exchange of surface DO with atmospheric HO. Moreover, a H resonance was observed for samples dried under a variety of conditions, including in vacuo heating to 150°C. In contrast, a sample heated to 500°C produced no deuterium resonance, indicating that structural water had been released by that temperature. We propose that water is located in the c-axis channels. Because structural water is observed even for apatites with very low carbonate content, some of the water molecules must lie between the monovalent ions. [ABSTRACT FROM AUTHOR]

To present the imaging and perfusion data obtained in nine patients with pilocytic astrocytomas (PA) and to discuss the original functional issues of this technique. Nine patients with pathologically proven PA underwent conventional and perfusion MR imaging. Various areas of relative cerebral blood volume (rCBV) within the tumors were obtained. The maximum rCBV ratios were identified and considered as representative of the tumor. The results were compared with the pathological findings. In all patients, rCBV was <1.5 (mean 1) and the signal intensity curve overshot the baseline. PA tend to have low rCBV values and a first-pass curve that crosses the baseline. These characteristics may be explained by the histological profile of the tumoral vascularity and are of relevance in the identification of these rare tumors. [ABSTRACT FROM AUTHOR]

The study of the population dynamics of aquatic oligochaetes is still largely a descriptive subject. However, going beyond description is essential in any field of science. This paper analyses the methodological approaches that can be used in this process, together with some examples from each of these approaches as they have been applied to aquatic oligochaetes. Observation and experiments in the field, laboratory experiments, and mathematical models are reviewed. Increased use of tools that are regarded as standard in the field of population dynamics at large and interaction with applied disciplines are advocated as ways to improve the quality of research in this field. [ABSTRACT FROM AUTHOR]

Abstract A mathematical matrix model was formulated to investigate the response of Daphnia obtusa population dynamics to the changes in the water chemistry of Lake Orta before and after the liming operation. Model parameters were estimated from experimental laboratory data. Model analysis showed that water chemistry changes induced by liming affected mainly egg survival and predicted the highest population growth at pH?6. Whereas increased egg mortality heavily inhibits population growth rate, the model still predicts a long term tendency of the population to increase in number. However, both before and after the liming operation due to high food availability in the laboratory, egg production was higher under all experimental conditions than in the field. When food limitation is accounted for and more realistic, field based estimates of egg production are used, the model predicts the extinction of D. obtusa population in the lake. This suggests that the effects of water chemistry changes on egg mortality had a critical role in the disappearance of D. obtusa from Lake Orta and may even adequately explain the extinction of this population. [ABSTRACT FROM AUTHOR]

Laser Raman microprobe spectroscopy, which characterizes the molecular structure of a mineral, was used to analyze microscopically small regions of bioapatite in mouse femora in order to study the effect of mouse age and in vitro fluoride treatment on the bone mineral (i.e., mineral identity and degree of crystallinity). Both femora that had and those that had not undergone in vitro NaF treatment underwent point analysis of 1 micron spots in the center of the compact bone's cross-section. The Raman spectra of bones treated with fluoride showed a peak up-shift of the PO4 vibration mode from 961 to 964 delta cm-1 indicating a conversion from a carbonated hydroxylapatitic to a carbonated fluorapatitic mineral phase. The spectral band width of the 961 delta cm-1 PO4 vibration in femora of 4-, 10-, and 24-week-old mice showed that aging, as well as in vitro treatment with 1.5 M NaF for 12 hours, significantly increases the degree of crystallinity of the bioapatite. In vitro fluoridation of 10-week-old mouse femora increased the bioapatite's degree of crystallinity to about the same degree as did aging to 24 weeks. Four-point bending tests indicated that the age-related increase in crystallinity of untreated bones was associated with decreased deformation to failure, i.e., increased brittleness. In contrast, the increased crystallinity following fluoridation of 10-week-old bones was associated with increased deformation, i.e., increased ductility, perhaps due to the altered mineral composition. This study shows that the laser Raman microprobe readily detects the conversion of carbonated hydroxylapatite to carbonated fluorapatite, as well as changes in crystallinity of either mineral phase, in microscopically small regions of a bone sample. [ABSTRACT FROM AUTHOR]

Focuses on studies regarding comparison among different population models of aquatic oligochaete species Limnodrilus hoffmeisteri Claparède. Several obstacles related to population studies; Possible solutions to remove these obstacles; Measurement of effect of age, size and life stage on survival, growth and fecundity of the species.

Presents research which argues for the existence of highly acidic lakes and ground waters in the North American Permian period. Where evaporites are located; Use of laser Raman microprobe analysis; Modern analogues of such systems; Traits of systems; Implications of research.

This corrects the article DOI: 10.1038/srep16511 [ABSTRACT FROM AUTHOR]

Fossil remains of the most ancient, minute forms of life on Earth and other planets are hard to recognize. Schopf et al. claim to have identified the biological remnant material known as kerogen in microscopic entities in rock by using Raman spectroscopic analysis. On the basis of a substantial body of published evidence, however, we contend that the Raman spectra of Schopf et al. indicate that these are disordered carbonaceous materials of indeterminate origin. We maintain that Raman spectroscopy cannot be used to identify microfossils unambiguously, although it is a useful technique for pinpointing promising microscopic entities for further investigation. [ABSTRACT FROM AUTHOR]

The outermost enamel of the human tooth and the rostrum of the whale Mesoplodon densirostris are two highly mineralized tissues that contain over 95 wt.% mineral, i.e., bioapatite. However, the same mineral type (carbonated hydroxylapatite) does not yield the same material properties, as revealed by Raman spectroscopy, scanning electron microscopy, electron microprobe analysis, and synchrotron X-ray diffraction analysis. Overall, the outermost enamel of a tooth has more homogeneous physical and chemical features than the rostrum. Chemical comparison of rostrum and enamel shows bioapatite in the rostrum to be enriched in Na, Mg, CO3, and S, whereas the outermost enamel shows only a slightly enriched Cl concentration. Morphologically, mineral rods (at tens of μm scale), crystallites and prisms (at μm and sub-μm scale), and platelets (at tens of nm scale) all demonstrate less organized texture in the rostrum than in enamel. Such contrasts between two mineralized tissues suggest distinct pathways of biomineralization, e.g., the nature of the equilibrium between mineral and body fluid. This study illustrates the remarkable flexibility of the apatite mineral structure to match its chemical and physical properties to specific biological needs within the same animal or between species. [ABSTRACT FROM AUTHOR]

The lack of any reliable method for assessing the age of individualscollected in the field has often been considered a major obstacle for population studies in aquatic oligochaetes. One possible solution could be the adoption of other variables, such as weight or stage, forthe definition of the population structure; this approach would be useful if allowed good predictions about population growth. We measured, under laboratory conditions, the effect of age, size and life stage on survival, growth and fecundity of Limnodrilus hoffmeisteri Claparede. The results are used to establish four matrix population models, based respectively on the classification of the individuals by age,weight and stage and on a mixed classification. Matrix population models make the assumptions that the individuals in a population can bearranged in a number of discrete classes and that time is a discretevariable. In these models, the population is represented by a vector(each element in the vector is the number of individuals in a class)and the demographic coefficients (survival, growth and fecundity) are collected in a square matrix. The estimate of ?, the potential longterm population growth rate and its confidence interval were taken from the four models using the jackknife method. The width of the confidence interval is a measure of the effectiveness of the models and thus of the classification of the individuals. The results suggest that weight is inefficient as a criterion for the definition of population structure of L. hoffmeisteri in comparison to age and stage. [ABSTRACT FROM AUTHOR]

A TaqI polymorphism, located in intron 4 of the faciogenital dysplasia ( FGD1) gene, the gene responsible for Aarskog syndrome, is described. FGD1 encodes a putative Rho/Rac guanine nucleotide exchange factor involved in mammalian morphogenesis. The identification of an intragenic polymorphism will facilitate the accurate carrier detection of individuals at risk for Aarskog syndrome. [ABSTRACT FROM AUTHOR]