Spatial Variation in Morphometry in Vanzosaura rubricauda (Squamata, Gymnophthalmidae) from Open Habitats of South America and its Environmental Correlates

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of environmental factors in the adherence of an atypical enteropathogenic Escherichia coli strain to epithelial cells

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Land cover change and environmental quality assessment using GIS techniques: a case study in Brazilian Southeastern region for the period 1988-2003

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Parasitological Data as Monitors of Environmental Health

When an appropriate fish host is selected, analysis of its parasites offers a useful, reliable, economical, telescoped indication or monitor of environmental health. The value of that information increases when corroborated by another non-parasitological technique. The analysis of parasites is not necessarily simple because not all hosts serve as good models and because the number of species, presence of specific species, intensity of infections, life histories of species, location of species in hosts, and host response for each parasitic species have to be addressed individually to assure usefulness of the tool. Also, different anthropogenic contaminants act in a distinct manner relative to hosts, parasites, and each other as well as being influenced by natural environmental conditions. Total values for all parasitic species infecting a sample cannot necessarily be grouped together. For example, an abundance of numbers of either species or individuals can indicate either a healthy or an unhealthy environment, depending on the species of parasite. Moreover, depending on the parasitic species, its infection, and the time chosen for collection/examination, the assessment may indicate a chronic or acute state of the environmental health. For most types of analyses, the host should be one that has a restricted home range, can be infected by numerous species of parasites, many of which have a variety of additional hosts in their life cycles, and can be readily sampled. Data on parasitic infections in the western mosquitofish (Gambusia affinis), a fish that meets the criteria in two separate studies, illustrate the usefulness of that host as a model to indicate both healthy and detrimentally influenced environments. In those studies, species richness, intensity of select species, host resistance, other hosts involved in life cycles, and other factors all relate to site and contaminating discharge.

Arctic Report Card 2007: Tracking Recent Environmental Changes

Collectively, the observations indicate that the overall warming of the Arctic system continued in 2007. There are some elements that are stabilizing or returning to climatological norms. These mixed tendencies illustrate the sensitivity and complexity of the Arctic System. Atmosphere: Hot spot shifts toward Europe Ocean: North Pole Temperatures at depth returning to 1990s values Sea Ice: Summer extent at record minimum Greenland: Recent warm temperatures associated with net ice loss Biology: increasing tundra shrub cover and variable treeline advance; up to 80% declines in some caribou herds while goose populations double Land: Increase in permafrost temperatures The Arctic Report Card 2007 is introduced as a means of presenting clear, reliable and concise information on recent observations of environmental conditions in the Arctic, relative to historical time series records. It provides a method of updating and expanding the content of the State of the Arctic Report, published in fall 2006, to reflect current conditions. Material presented in the Report Card is prepared by an international team of scientists and is peer-reviewed by topical experts nominated by the US Polar Research Board. The audience for the Arctic Report Card is wide, including scientists, students, teachers, decision makers and the general public interested in Arctic environment and science. The web-based format will facilitate future timely updates of the content.

Occurrence and behavior of butyltins in intertidal and shallow subtidal surface sediments of an estuarine beach under different sampling conditions

Contamination by butyltin compounds (BTs) has been reported in estuarine environments worldwide, with serious impacts on the biota of these areas. Considering that BTs can be degraded by varying environmental conditions such as incident light and salinity, the short-term variations in such factors may lead to inaccurate estimates of BTs concentrations in nature. Therefore, the present study aimed to evaluate the possibility that measurements of BTs in estuarine sediments are influenced by different sampling conditions, including period of the day (day or night), tidal zone (intertidal or subtidal), and tides (high or low). The study area is located on the Brazilian southeastern coast, Sao Vicente Estuary, at Pescadores Beach, where BT contamination was previously detected. Three replicate samples of surface sediment were collected randomly in each combination of period of the day, tidal zone, and tide condition, from three subareas along the beach, totaling 72 samples. BTs were analyzed by GC-PFPD using a tin filter and a VF-5 column, by means of a validated method. The concentrations of tributyltin (TBT), dibutyltin (DBT), and monobutyltin (MBT) ranged from undetectable to 161 ng Sn g(-1) (d.w.). In most samples (71%), only MBT was quantifiable, whereas TBTs were measured in only 14, suggesting either an old contamination or rapid degradation processes. DBT was found in 27 samples, but could be quantified in only one. MBT concentrations did not differ significantly with time of day, zones, or tide conditions. DBT and TBT could not be compared under all these environmental conditions, because only a few samples were above the quantification limit. Pooled samples of TBT did not reveal any difference between day and night. These results indicated that, in assessing contamination by butyltin compounds, surface-sediment samples can be collected in any environmental conditions. However, the wide variation of BTs concentrations in the study area, i.e., over a very small geographic scale, illustrates the need for representative hierarchical and composite sampling designs that are compatible with the multiscalar temporal and spatial variability common to most marine systems. The use of such sampling designs will be necessary for future attempts to quantitatively evaluate and monitor the occurrence and impact of these compounds in nature

Relationship between ozone, meteorological conditions, gas exchange and leaf injury in Nicotiana tabacum Bel-W3 in a sub-tropical region

The city of Sao Paulo is located in a subtropical region whose climate exhibits few defined seasons as well as frequent oscillations in temperature and rainfall throughout the year. In addition to interfering with physiological processes, these peculiar climatic dynamics influence the formation of O-3 and its influx into leaves, causing species used as bioindicators in temperate climates to be ineffective here. This study evaluated gas exchange variations in CO2 and H2O and leaf injuries induced by O-3 in Nicotiana tabacum Bel-W3 in relation to oscillations in environmental conditions. Plants were exposed to an O-3-polluted environment for fifteen periods of fourteen days each throughout 2008. Gas exchange and O-3 were higher during the summer and winter but were highly variable in all seasons. Severe injuries occurred during the winter and spring, with significant variation in this parameter being observed throughout the year. An analysis of biotic and abiotic variables revealed complex relationships among them, with great importance of meteorological factors in plant responses. We conclude that under unstable climatic conditions, the relationship between O-3 flux and injury is weak, and the qualitative character of biomonitoring is further confirmed. (c) 2012 Elsevier Ltd. All rights reserved.

Interannual variation in commercial oyster (Crassostrea gigas) farming in the sea (Florianopolis, Brazil, 27 degrees 44 ' S; 48 degrees 33 ' W) in relation to temperature, chlorophyll a and associated oceanographic conditions

Aquaculture of filter-feeding bivalve mollusks involves the fruitful conversion of marine particulate organic matter into premium protein of high nutritive value. Culture performance of bivalves is largely dependent on hydrological conditions and directly affected by e. g. temperature and chlorophyll levels. Accordingly, these parameters may be related with seasonality but also with oceanographic features combined with climate events. Yields of Pacific cupped oyster (Crassostrea gigas) reared at commercial procedures in suspended structures (long-lines) in a sheltered bay in Southern Brazil (Santa Catarina State, 27S 43'; 48 W 30') were evaluated in relation to local environmental conditions: sea surface temperature, chlorophyll a concentration, and associate effects of cold fronts events and El Nino and La Nina periods. Outputs from four consecutive commercial crop years were analyzed (2005/06, 2006/07, 2007/08, 2008/09) in terms of oyster survival and development time during the following grow-out phases of the culture cycle: seed to juvenile, juvenile to adult, adult to marketable. Since culture management and genetics were standardized significant differences verified among crop performance could be mostly related to environmental effects. Time series of temperature and chlorophyll a (remote sensing data) from crop periods displayed significant seasonal and interannual variation. As expected, performance during initial grow-out stages (seed to juvenile) was critical for final crop yield. Temperature was the main factor affecting survival in these initial stages with a trend of negative correlation, though not statistically significant. On the other hand, oyster development rate was significantly and positively affected by chlorophyll a concentration. Chlorophyll a values could be increased by upwelled cold nutrient-rich South Atlantic Central Water (SACW, related to predominant Northern winds) though further dependent on occurrence of Southern winds (cold fronts) to assist seawater penetration into the sheltered farming area. Lower salinity nutrient-rich northward drifted waters from La Plata River discharge may also result in chlorophyll a rise in the farming area. The El Nino period (July 2006 to February 2007) coincided with lower chlorophyll a levels in the farming site that may be related to both decreased number of cold fronts as well as predominance of Northern winds that retain northward spreading of La Plata River discharge waters. In contrast, the La Nina period (August 2007 to June 2008) corresponded to higher chlorophyll a values in the farming area by both upwelling of SACW and penetration of La Plata River discharge water assisted by increased occurrence of Southern winds and cold fronts. The recognition of the potentially changing climate and effects upon the environment will be an important step in planning future development of bivalve aquaculture.

Gene expression and phenotypic traits of Aggregatibacter actinomycetemcomitans in response to environmental changes

Background and Objective: Periodontopathogens experience several challenges in the oral cavity that may influence their transcription profile and resulting phenotype. This study evaluated the effect of environmental changes on phenotype and gene expression in a serotype b Aggregatibacter actinomycetemcomitans isolate. Material and Methods: Cultures in early exponential phase and at the start of stationary growth phase in microaerophilic and anaerobic atmospheres were evaluated. Cell hydrophobic properties were measured by adherence to n-hexadecane; in addition, adhesion to, and the ability to invade, KB cells was evaluated. Relative transcription of 12 virulence-associated genes was determined by real-time reverse transcritption quantitative PCR. Results: The culture conditions tested in this study were found to influence the phenotypic and genotypic traits of A. actinomycetemcomitans. Cells cultured in microaerophilic conditions were the most hydrophobic, reached the highest adhesion efficiency and showed up-regulation of omp100 (which encodes an adhesion) and pga (related to polysaccharide synthesis). Cells grown anaerobically were more invasive to epithelial cells and showed up-regulation of genes involved in host-cell invasion or apoptosis induction (such as apaH, omp29, cagE and cdtB) and in adhesion to extracellular matrix protein (emaA). Conclusion: Environmental conditions of different oral habitats may influence the expression of factors involved in the binding of A. actinomycetemcomitans to host tissues and the damage resulting thereby, and thus should be considered in in-vitro studies assessing its pathogenic potential.

The structure of planktonic communities under variable coastal upwelling conditions off Cape Ghir (31ºN), in the Canary Current System (NW Africa)

Universidad de Las Palmas de Gran Canaria. Facultad de Ciencias del Mar. Programa de doctorado en Oceanografía. Diploma de Estudios Avanzados

Performance evaluation of low environmental impact asphalt concretes using the mechanistic empirical design method based on laboratory fatigue and permanent deformation models

The "sustainability" concept relates to the prolonging of human economic systems with as little detrimental impact on ecological systems as possible. Construction that exhibits good environmental stewardship and practices that conserve resources in a manner that allow growth and development to be sustained for the long-term without degrading the environment are indispensable in a developed society. Past, current and future advancements in asphalt as an environmentally sustainable paving material are especially important because the quantities of asphalt used annually in Europe as well as in the U.S. are large. The asphalt industry is still developing technological improvements that will reduce the environmental impact without affecting the final mechanical performance. Warm mix asphalt (WMA) is a type of asphalt mix requiring lower production temperatures compared to hot mix asphalt (HMA), while aiming to maintain the desired post construction properties of traditional HMA. Lowering the production temperature reduce the fuel usage and the production of emissions therefore and that improve conditions for workers and supports the sustainable development. Even the crumb-rubber modifier (CRM), with shredded automobile tires and used in the United States since the mid 1980s, has proven to be an environmentally friendly alternative to conventional asphalt pavement. Furthermore, the use of waste tires is not only relevant in an environmental aspect but also for the engineering properties of asphalt [Pennisi E., 1992]. This research project is aimed to demonstrate the dual value of these Asphalt Mixes in regards to the environmental and mechanical performance and to suggest a low environmental impact design procedure. In fact, the use of eco-friendly materials is the first phase towards an eco-compatible design but it cannot be the only step. The eco-compatible approach should be extended also to the design method and material characterization because only with these phases is it possible to exploit the maximum potential properties of the used materials. Appropriate asphalt concrete characterization is essential and vital for realistic performance prediction of asphalt concrete pavements. Volumetric (Mix design) and mechanical (Permanent deformation and Fatigue performance) properties are important factors to consider. Moreover, an advanced and efficient design method is necessary in order to correctly use the material. A design method such as a Mechanistic-Empirical approach, consisting of a structural model capable of predicting the state of stresses and strains within the pavement structure under the different traffic and environmental conditions, was the application of choice. In particular this study focus on the CalME and its Incremental-Recursive (I-R) procedure, based on damage models for fatigue and permanent shear strain related to the surface cracking and to the rutting respectively. It works in increments of time and, using the output from one increment, recursively, as input to the next increment, predicts the pavement conditions in terms of layer moduli, fatigue cracking, rutting and roughness. This software procedure was adopted in order to verify the mechanical properties of the study mixes and the reciprocal relationship between surface layer and pavement structure in terms of fatigue and permanent deformation with defined traffic and environmental conditions. The asphalt mixes studied were used in a pavement structure as surface layer of 60 mm thickness. The performance of the pavement was compared to the performance of the same pavement structure where different kinds of asphalt concrete were used as surface layer. In comparison to a conventional asphalt concrete, three eco-friendly materials, two warm mix asphalt and a rubberized asphalt concrete, were analyzed. The First Two Chapters summarize the necessary steps aimed to satisfy the sustainable pavement design procedure. In Chapter I the problem of asphalt pavement eco-compatible design was introduced. The low environmental impact materials such as the Warm Mix Asphalt and the Rubberized Asphalt Concrete were described in detail. In addition the value of a rational asphalt pavement design method was discussed. Chapter II underlines the importance of a deep laboratory characterization based on appropriate materials selection and performance evaluation. In Chapter III, CalME is introduced trough a specific explanation of the different equipped design approaches and specifically explaining the I-R procedure. In Chapter IV, the experimental program is presented with a explanation of test laboratory devices adopted. The Fatigue and Rutting performances of the study mixes are shown respectively in Chapter V and VI. Through these laboratory test data the CalME I-R models parameters for Master Curve, fatigue damage and permanent shear strain were evaluated. Lastly, in Chapter VII, the results of the asphalt pavement structures simulations with different surface layers were reported. For each pavement structure, the total surface cracking, the total rutting, the fatigue damage and the rutting depth in each bound layer were analyzed.

Speciation of Pu(III) in the environmental system humic substances-groundwater-kaolinite

For the safety assessments of nuclear waste repositories, the possible migration of the radiotoxic waste into environment must be considered. Since plutonium is the major contribution at the radiotoxicity of spent nuclear waste, it requires special care with respect to its mobilization into the groundwater. Plutonium has one of the most complicated chemistry of all elements. It can coexist in 4 oxidation states parallel in one solution. In this work is shown that in the presence of humic substances it is reduced to the Pu(III) and Pu(IV). This work has the focus on the interaction of Pu(III) with natural occurring compounds (humic substances and clay minerals bzw. Kaolinite), while Pu(IV) was studied in a parallel doctoral work by Banik (in preparation). As plutonium is expected under extreme low concentrations in the environment, very sensitive methods are needed to monitor its presence and for its speciation. Resonance ionization mass spectrometry (RIMS), was used for determining the concentration of Pu in environmental samples, with a detection limit of 106- 107 atoms. For the speciation of plutonium CE-ICP-MS was routinely used to monitor the behaviour of Pu in the presence of humic substances. In order to reduce the detection limits of the speciation methods, the coupling of CE to RIMS was proposed. The first steps have shown that this can be a powerful tool for studies of pu under environmental conditions. Further, the first steps in the coupling of two parallel working detectors (DAD and ICP_MS ) to CE was performed, for the enabling a precise study of the complexation constants of plutonium with humic substances. The redox stabilization of Pu(III) was studied and it was determined that NH2OHHCl can maintain Pu(III) in the reduced form up to pH 5.5 – 6. The complexation constants of Pu(III) with Aldrich humic acid (AHA) were determined at pH 3 and 4. the logß = 6.2 – 6.8 found for these experiments was comparable with the literature. The sorption of Pu(III) onto kaolinite was studied in batch experiments and it was determine dthat the pH edge was at pH ~ 5.5. The speciation of plutonium on the surface of kaolinite was studied by EXAFS/XANES. It was determined that the sorbed species was Pu(IV). The influence of AHA on the sorption of Pu(III) onto kaolinite was also investigated. It was determined that at pH < 5 the adsorption is enhanced by the presence of AHA (25 mg/L), while at pH > 6 the adsorption is strongly impaired (depending also on the adding sequence of the components), leading to a mobilization of plutonium in solution.

Novel etheroatom containing aliphatic polyesters for biomedical and environmental applications

Biodegradable polymers for short time applications have attracted much interest all over the world. The reason behind this growing interest is the incompatibility of the polymeric wastes with the environment where they are disposed after usage. Synthetic aliphatic polyesters represent one of the most economically competitive biodegradable polymers. In addition, they gained considerable attention as they combine biodegradability and biocompatibility with interesting physical and chemical properties. In this framework, the present research work focused on the modification by reactive blending and polycondensation of two different aliphatic polyesters, namely poly(butylene succinate) (PBS) and poly(butylene 1,4-cyclohexanedicarboxylate) (PBCE). Both are characterized by good thermal properties, but their mechanical characteristics do not fit the requirements for applications in which high flexibility is requested and, moreover, both show slow biodegradation rate. With the aim of developing new materials with improved characteristics with respect to the parent homopolymers, novel etheroatom containing PBS and PBCE-based fully aliphatic polyesters and copolyesters have been therefore synthesized and carefully characterized. The introduction of oxygen or sulphur atoms along the polymer chains, by acting on chemical composition or molecular architecture, tailored solid-state properties and biodegradation rate: type and amount of comonomeric units and sequence distribution deeply affected the material final properties owing, among all, to the hydrophobic/hydrophilic ratio and to the different ability of the polymer to crystallize. The versatility of the synthesized copolymers has been well proved: as a matter of fact these polymers can be exploited both for biomedical and ecological applications. Feasibility of 3D electrospun scaffolds has been investigated, biocompatibility studies and controlled release of a model molecule showed good responses. As regards ecological applications, barrier properties and eco-toxicological assessments have been conducted with outstanding results. Finally, the ability of the novel polyesters to undergo both hydrolytic and enzymatic degradation has been demonstrated under physiological and environmental conditions.

High-resolution reconstruction of Holocene climate variability and environmental changes in the North Pacific using bivalve shells

Bivalve mollusk shells are useful tools for multi-species and multi-proxy paleoenvironmental reconstructions with a high temporal and spatial resolution. Past environmental conditions can be reconstructed from shell growth and stable oxygen and carbon isotope ratios, which present an archive for temperature, freshwater fluxes and primary productivity. The purpose of this thesis is the reconstruction of Holocene climate and environmental variations in the North Pacific with a high spatial and temporal resolution using marine bivalve shells. This thesis focuses on several different Holocene time periods and multiple regions in the North Pacific, including: Japan, Alaska (AK), British Columbia (BC) and Washington State, which are affected by the monsoon, Pacific Decadal Oscillation (PDO) and El Niño/Southern Oscillation (ENSO). Such high-resolution proxy data from the marine realm of mid- and high-latitudes are still rare. Therefore, this study contributes to the optimization and verification of climate models. However, before using bivalves for environmental reconstructions and seasonality studies, life history traits must be well studied to temporally align and interpret the geochemical record. These calibration studies are essential to ascertain the usefulness of selected bivalve species as paleoclimate proxy archives. This work focuses on two bivalve species, the short-lived Saxidomus gigantea and the long-lived Panopea abrupta. Sclerochronology and oxygen isotope ratios of different shell layers of P. abrupta were studied in order to test the reliability of this species as a climate archive. The annual increments are clearly discernable in umbonal shell portions and the increments widths should be measured in these shell portions. A reliable reconstruction of paleotemperatures may only be achieved by exclusively sampling the outer shell layer of multiple contemporaneous specimens. Life history traits (e.g., timing of growth line formation, duration of the growing season and growth rates) and stable isotope ratios of recent S. gigantea from AK and BC were analyzed in detail. Furthermore, a growth-temperature model based on S. gigantea shells from Alaska was established, which provides a better understanding of the hydrological changes related to the Alaska Coastal Current (ACC). This approach allows the independent measurement of water temperature and salinity from variations in the width of lunar daily growth increments of S. gigantea. Temperature explains 70% of the variability in shell growth. The model was calibrated and tested with modern shells and then applied to archaeological specimens. The time period between 988 and 1447 cal yrs BP was characterized by colder (~1-2°C) and much drier (2-5 PSU) summers, and a likely much slower flowing ACC than at present. In contrast, the summers during the time interval of 599-1014 cal yrs BP were colder (up to 3°C) and fresher (1-2 PSU) than today. The Aleutian Low may have been stronger and the ACC was probably flowing faster during this time.

Stream sediments analysis for geochemical mapping of Romagna Apennines (Northern Italy): monitoring and management tool of environmental resources at various scales

Geochemical mapping is a valuable tool for the control of territory that can be used not only in the identification of mineral resources and geological, agricultural and forestry studies but also in the monitoring of natural resources by giving solutions to environmental and economic problems. Stream sediments are widely used in the sampling campaigns carried out by the world's governments and research groups for their characteristics of broad representativeness of rocks and soils, for ease of sampling and for the possibility to conduct very detailed sampling In this context, the environmental role of stream sediments provides a good basis for the implementation of environmental management measures, in fact the composition of river sediments is an important factor in understanding the complex dynamics that develop within catchment basins therefore they represent a critical environmental compartment: they can persistently incorporate pollutants after a process of contamination and release into the biosphere if the environmental conditions change. It is essential to determine whether the concentrations of certain elements, in particular heavy metals, can be the result of natural erosion of rocks containing high concentrations of specific elements or are generated as residues of human activities related to a certain study area. This PhD thesis aims to extract from an extensive database on stream sediments of the Romagna rivers the widest spectrum of informations. The study involved low and high order stream in the mountain and hilly area, but also the sediments of the floodplain area, where intensive agriculture is active. The geochemical signals recorded by the stream sediments will be interpreted in order to reconstruct the natural variability related to bedrock and soil contribution, the effects of the river dynamics, the anomalous sites, and with the calculation of background values be able to evaluate their level of degradation and predict the environmental risk.