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The sediment of five mangrove in Pernambuco/Brazil was investigated to find a reference site for toxicity bioassays. Sediment characteristics, metal levels, and toxic effects on the nauplius of the copepod Tisbe biminiensis were studied. The sediment was composed by terrigenous muds and siliciclastic sands with medium to high organic matter contents. The Fe As association show most of the high concentrations and positive correlation among its constituents in the south. In the north, the Ca-Sr-La association is higher and exhibits positive correlation among its components that usually found in carbonate rocks. Very intense toxic effects were observed, mainly in the south, with >70 % reductions in development. As and Hg were positively correlated with mortality and decrease in development. The sediment quality at studied mangroves prevent their use as a reference site in bioassays. These could be linked to the direct/perennial contribution of geogenic sources associated with anthropogenic environmental impacts. • Estuarine sediment presented toxic effects to the copepod Tisbe biminiensi. • The As and Hg could be associated with observed toxic effects. • Studied mangroves cannot be used as reference sites in bioassays. • Copepod toxicity tests were useful to the pollution evaluation in estuarine sediments. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2008.12.018 Byline: B.F. Giannetti, S.H. Bonilla, C.C. Silva, C.M.V.B. Almeida Abstract: The complexity of the environment demands a well-constructed composite environmental index (CEI) to provide a useful tool to draw attention to environmental conditions and trends for policy purposes. Among the common difficulties in constructing a proper CEI are uncertainties due to the selection of the most representative underlying variables or indicators. A degree of uncertainty accompanies experts' judgments, and to deal with vague, subjective or inconsistent information, logic other than classic is required. This study analyzes a procedure that uses different experts' opinions in constructing a CEI, with the use of paraconsistent annotated logic. For this, a sensitivity analysis of the Environmental Sustainability Index (ESI 2005) was used as an example to assess the reliability of experts' opinions. The uncertainty due to the disagreement in experts' opinions clearly indicates that the forms we presently use to measure and monitor the actual environment are insufficient, that is, there is a lack of a 'science of sustainability'. Author Affiliation: LaFTA - Laboratorio de Fisico Quimica Teorica e Aplicada, LaPROMA - Laboratorio de Producao e Meio Ambiente, Programa de Pos-Graduacao em Engenharia de Producao, Universidade Paulista, R. Dr. Bacelar 1212, CEP 04026-002, Sao Paulo, Brazil Article History: Received 16 October 2007; Revised 28 November 2008; Accepted 29 December 2008

Abstract: The administration of exogenous melatonin can mimic the stimulatory effect of short days in advancing the onset of maximum reproductive parameters in seasonal rams. However, the animals need to be previously exposed to natural or artificial long days before responding to the melatonin treatment. The objective of this study was to test the effect of melatonin treatment on rams, initiated in mid May (end of spring) – when rams have already been exposed to some months of increasing day length, but not to artificial long day treatment on testicular size and semen characteristics. Sixteen rams (8 Texel and 8 Charollais) were treated with melatonin subcutaneous implants (REGULIN®) on 22 May and 20 June (spring/summer) (n =8) or remained untreated (n =8). Blood samples were taken from all rams over a 24-h period to determine the plasma melatonin concentration profile. The ram''s testes were all measured four times at 2-week intervals, and testicular volume and scrotal circumference determined. Semen was collected using the artificial vagina at two occasions (end of June and end of August), when 5 ejaculates were obtained from each ram and analysed for semen volume and sperm concentration. The plasma melatonin levels in the melatonin-treated rams were significantly higher than for the untreated rams (P <0.01). During the dark phase of the day, the plasma melatonin concentrations were elevated (P <0.01) in the control, but not in the melatonin-treated rams. Scrotal circumference and testicular volume increased (P <0.001) from May to July (late spring to mid-summer) in both groups of rams, with no significant difference being detected between groups. Semen volume and sperm concentration increased (P <0.01) from June (summer) to July/September (summer/autumn) in both treatment groups. Melatonin treatment of the rams did not affect the semen volume or sperm concentration during any of the collection periods. Data suggest that the treatment of rams with melatonin implants initiated in late spring, without a priming period of long days preceding the treatment, is not sufficient stimulus to increase testis growth and sperm production. [Copyright &y& Elsevier]

Abstract: In this paper we present the preparation, by the sol–gel method, of a transparent SiO2:Li2O:Nb2O5 glass doped with Tm3+. The dried gel was heat-treated (HT), in air, at temperatures between 500 and 800°C. The obtained glasses and glass–ceramics were studied by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), dc conductivity (σ dc), ac conductivity (σ ac) and by dielectric measurements. The X-ray diffraction patterns show that SiO2 and LiNbO3 crystal phases are present in the samples treated at temperatures above 650°C. Besides the SiO2 and LiNbO3, TmNbO4 crystal phase was detected in the samples treated above 750°C. The XRD and SEM show that the average particles size and number increases with the rise of the HT temperature. The electrical and dielectrical properties were related with the glass and glass–ceramics microstructure. [Copyright &y& Elsevier]

Abstract: Ceramics with high dielectric permittivity are of intense interest due to their enabling role in the miniaturization of electronic devices. In particular, lithium niobate (LiNbO3), due to its remarkable pyroelectrical, piezoelectrical and photorefractive properties, is an important material for a large variety of technological applications. Lithium ferrite (LiFe5O8) is another very interesting ferromagnetic material due to its square hysteresis loop, high Curie temperature. It is of technology importance as a low-cost substitute of garnet ferrites in several devices. In this work we present the studies on the composite material with LiNbO3 and LiFe5O8 here described by (x) LiFe5O8−(100−x) LiNbO3 with x =0, 25, 50, 75 and 100 (wt%). The structure and the dielectric properties of the samples, processed in a domestic microwave oven and by the conventional solid state method, are discussed. The influence of thermal treatment time and temperature was investigated. [Copyright &y& Elsevier]

Abstract: The lithium ferrite (LiFe5O8) is a very interesting ferromagnetic material due to its square hysteresis loop and high Curie temperature. It has attracted the attention of scientists and engineers for a long time with regard to their application as a low-cost substitute of garnet ferrites in several devices. In this work we present the first studies of the (x)SiO2-(1−x)[Li2O.5Fe2O3] (% mol) glass and glass–ceramic, with x =94 and x =97%, prepared by the sol–gel method. The influence of the heat-treatment parameters, in the glass and glass–ceramics structure prepared was investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and impedance spectroscopy measurements. The increase of the volume ratio between the LiFe5O8 particles and the glass matrix leads to an increase of the conductivity. The dielectric measurements show that the crystalline growth orientation of the LiFe5O8 particles, embedded in the glass matrix, is random. [Copyright &y& Elsevier]

Abstract: On a preliminary screening, relevant in vitro antiproliferative activity was observed to the crude ethanolic extract of Pterodon pubescens seed oil against the human melanoma cell line SK MEL 37. The diethyl ether fraction from crude ethanolic extract which exhibited stronger activity was submitted to fractionation by gradient elution with hexane/ethyl acetate. Subfraction A, eluted by hexane/ethyl acetate (80:20), was essentially the most active between all the assayed subfractions with an IC50 of 37μg/ml calculated by the MTT colorimetric method. At this concentration, subfraction A caused morphological features and internucleosomal DNA fragmentation pattern of apoptosis. Through chromatographic separation, the furane diterpene 1 was isolated from this active subfraction and identified by spectral techniques. Compound 1 showed an IC50 value of 32μM and fluorescence staining with DAPI revealed some typical nuclear changes which are characteristic of apoptosis. These findings support a role for diterpenoids vouacapan-type skeleton as a model to develop new anticancer agents. [Copyright &y& Elsevier]

Abstract: The present study focuses on apatite coating on collagen films, with various different densities of carboxyl groups, using an alternate soaking process. Anionic collagen (AC), which has different densities of carboxylic groups compared to native collagen (NC), was obtained by hydrolysis of carboxyamides of asparagine and glutamine residues. From X-ray diffraction analysis, apatite was found to be coated on AC and NC films. Peaks ascribed to apatite were observed at 26° and 32° in the diffraction patterns of hydroxyapatite crystals. The amount of apatite coated on both AC and NC collagen films continued to increase up to 100 reaction cycles. However, there is a significant difference in apatite coating between the two films. The amount of apatite formed on the surface of AC film increased 1.24 times faster than on NC film. The scanning electron photomicrograph images of the mineralized NC and the AC film coatings formed after 100cycles show that regular porous apatite coating had formed within the collagen fibrils. These results suggest that the higher content of carboxyl groups in AC plays an effective role in the heterogeneous nucleation of apatite in the body environment. [Copyright &y& Elsevier]

Abstract: The present study was designated to evaluate the antileishmanial activity of acid and basic fractions that were obtained after acid-basic extraction, from ethanolic 70% crude extract and pure compounds from the stem bark of Aspidosperma ramiflorum. The basic alkaloidal fraction presented a good activity against the extracellular form (promastigotes) of Leishmania (L.) amazonensis (LD50 value<47μg/ml). Based on these findings, the basic fraction was fractionated on silica gel column chromatography in a bioassay-guided fractionation affording individual purified ramiflorines A and B. Both ramiflorines A and B showed significant activity against Leishmania (L.) amazonensis (LD50 values of 16.3±1.6μg/ml and 4.9±0.9μg/ml, respectively). Our results are promising, showing that these compounds are biologically active against Gram-positive bacteria. [Copyright &y& Elsevier]

Abstract: It is accepted that an important source of variation in the response of anoestrous ewes, to the introduction of rams, is the intensity of male stimulation. The aim of this study was to investigate strategies capable of increasing the impact and transmission of the ram stimuli. In Experiment 1, two groups of seven ewes (Bluefaced Leicester♂×Swaledale♀) were individually penned with one ram and for the next 6h the rams either remained in the pen or were replaced hourly. Blood samples revealed no difference in the pattern of plasma LH secretion. In Experiment 2, three groups of 16 ewes were either introduced to one ram, individually (H) or in groups of 8 (L), or remained isolated. Ram introduction increased the plasma LH pulsatility (P <0.001). H ewes displayed more (nine versus six) male-induced LH pulses (pulses occurring within the first 45min) and more pulses per 8h intervals than the L group of ewes (1.9±0.3 versus 1.3±0.3), but these differences were not significant. It was concluded that (i) frequent replacement of rams within a few hours following ram introduction to ewes does not further improve the response of ewes, especially if the ram:ewe ratio is high; (ii) the characterization of the plasma LH secretion parameters during a period of 6–8h does not seem to be an effective method to detect small differences in the intensity of stimulation received by the ewes when exposed to rams; (iii) North Country Mule ewes (Bluefaced Leicester♂×Swaledale♀) in the UK respond to the presence of rams in spring (late oestrous/early anoestrous season) with an elevation in plasma LH secretion. [Copyright &y& Elsevier]

Abstract: The hydroxyapatite biomaterial (Ca10(PO4)6(OH)2 – HAP) is the main mineral constituent of teeth and bones, with excellent biocompatibility with hard and muscle tissues. These materials exhibit several problems of handling and fabrication, which can be overcome by mixing them with a suitable binder. In this study, a microwave process was used to produce hydroxyapatite using the starting materials CaCl2 and Na2HPO4 with previous precipitation. The mixture was exposed to microwave radiation for 5, 10, 15 and 20min through domestic microwave ovens with an output power of 1kW and frequency oscillation of 2.45GHz. The samples were analyzed by X-ray powder diffraction, scanning electron microscopy, energy dispersive X-ray, dc conductivity and impedance spectroscopy. X-ray powder diffraction revealed the formation of HAP after 5min of exposure. The presence of a low crystallinity state and the transition, with the rise of radiation exposure time, to a crystalline phase was related to the Ca/P mass and Ca/P atomic ratio. The presence of this low crystalline phase, detected by X-ray powder diffraction and scanning electron microscopy, seems to have a direct influence on electrical and dielectrical characteristics. [Copyright &y& Elsevier]

Abstract: In this paper, we present the preparation and electrical properties of nanocrystalline powders of hydroxyapatite (HAP) bioceramics, produced using the starting materials Ca(H2PO4)2, Ca(OH)2 and a high energy dry ball milling technique. Titanium calcium phosphate (CaP–Ti) was also prepared, the raw materials Ca(H2PO4)2 and TiO2, and examined. The HAP was obtained of milling 5, 10 and 15h while in the reaction with CaP–Ti, the CaTi4P6O24 phase was obtained after 5, 10 and 15h of milling. The HAP and the ceramic calcium phosphate with titanium (CaP–Ti) were studied by X-ray powder diffraction, DC and AC conductivity and dielectric constant measurements. [Copyright &y& Elsevier]

Calcium phosphate-based bioceramics, mainly in the form of hydroxyapatite, Ca10(PO4)6(OH)2—HAP, is the main mineral constituent of teeth and bones with excellent biocompatibility with hard and muscle tissues. These materials exhibit several problems of handling and fabrication, which can be overcome by mixing them with a suitable binder. The dry milling process of fabrication of HAP presents the advantage that melting is not necessary and the powder obtained is nanocrystalline. The high efficiency of the dry milling process opens a new way to produce commercial amount of nanocrystalline HAP and others bioceramic. In this work dry mechanical alloying has been used to produce nanocrystalline powders of HAP using three different experimental procedures (HAPA: Ca(H2PO4)2 + Ca(OH)2; HAPB: Ca(H2PO4)2 + CaCO3; and HAPC: CaHPO4 + CaCO3). HAP was obtained after 5, 10 and 15 h of milling in the reactions HAPA and HAPB, but it is necessary 15 h of milling in the reaction HAPC to obtain HAP. In order to improve the mechanical properties of HAP calcium phosphate ceramics, with titanium (CaP-Ti) and zirconium (CaP-Zr), have been prepared by dry ball milling using two different experimental procedures: CaP-Ti1: Ca(H2PO4)2 + TiO2; CaP-Ti2: CaHPO4 + TiO2; and CaP-Zr1: Ca(H2PO4)2 + ZrO2, CaP-Zr2: CaHPO4 + ZrO2. The calcium titanium phosphate phase, CaTi4P6O24, was obtained in the reaction CaP-Ti1. In the reactions CaP-Ti2, CaP-Zr1 and CaP-Zr2, it was not observed the formation of any calcium phosphate phase even after 15 h of dry mechanical alloying. The milled HAP and the ceramics systems obtained were characterized by X-ray powder diffraction, infrared and Raman scattering spectroscopy. [Copyright &y& Elsevier]

Silicon nitride-based ceramics are potential candidates as materials for orthopedic implants due to their chemical stability associated with suitable fracture toughness and propitious tribologic characteristics. Therefore, in this work, dense silicon nitride components are investigated considering their suitability as biomaterials. Initially, two different compositions of silicon nitride were considered, using ytterbium, yttrium and aluminum oxides as sintering aids. The materials were sintered in a carbon resistance furnace under nitrogen atmosphere and were analyzed by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) in order to characterize the microstructure. Indentation method was applied in order to obtain hardness and fracture toughness measurements, and in vitro test of cytotoxicity was performed for a preliminary biological evaluation. A microstructure composed of grains of beta-silicon nitride distributed in a secondary phase was observed. The samples achieved fracture toughness values of 5 MPa m1/2 and Vickers hardness values of 13 GPa. Since a nontoxic behavior has been observed during the cytotoxicity tests with the samples, this finding suggests that silicon nitride-based ceramic can be used as a material for clinical applications. [Copyright &y& Elsevier]

Mechanical alloying has been used successfully to produce nanocrystalline powders of hydroxyapatite (HA) using three different procedures. The milled HA was studied by X-ray diffraction, Infrared, Raman scattering spectroscopy and Scanning Electron Microscopy (SEM). We obtained HA with different degrees of crystallinity and time of milling. The grain size analysis through SEM and XRD shows particles with dimensions of 36.9, 14.3 and 35.5 nm (for (R1), (R2) and (R3), respectively) forming bigger units with dimensions given by 117.2, 110.8 and 154.4 nm (for (R1), (R2) and (R3), respectively). The Energy-Dispersive Spectroscopy (EDS) analysis showed that an atomic ratio of Ca/P=1.67, 1.83 and 1.50 for reactions (R1), (R2) and (R3), respectively. These results suggest that the R1 nanocrystalline ceramic is closer to the expected value for the ratio Ca/P for hydroxyapatite, which is 5/31.67. The bioactivity analysis shows that all the samples implanted into the rabbits can be considered biocompatible, since they had been considered not toxic, had not caused inflammation and reject on the part of the organisms of the animals, during the period of implantation. The samples implanted in rabbits had presented new osseous tissue formation with the presence of osteoblasts cells. [Copyright &y& Elsevier]

In this paper mechanical alloying has been used successfully to produce nanocrystalline powders of hydroxyapatite (HA) using five different experimental procedures in a pure dry process. The milled HA were studied by X-ray powder diffraction, infrared and Raman scattering spectroscopy. For four different procedures, HA was obtained after a couple of hours of milling (in average 60 hours of milling, depending in the reaction procedure). This milling process, used to produce HA, presents the advantage that melting is not necessary and the powder obtained is nanocrystalline with crystallite size in the range of 22 nm to 39 nm. [Copyright &y& Elsevier]

Calcium phosphate based bioceramics, mainly in the form of hydroxyapatite (HA), have been in use in medicine and dentistry for the last 20 years. Applications include coatings of orthopaedic and dental implants, alveolar ridge augmentation, maxillofacial surgery, otolaryngology, and scaffolds for bone growth and as powders in total hip and knee surgery. These materials exhibit several problems of handling and fabrication, which can be overcome by mixing with a suitable binder. In this paper, mechanical alloying has been used successfully to produce nanocrystalline powders of HA using five different experimental procedures. The milled HA were studied by X-ray powder diffraction, infrared and Raman scattering spectroscopy. For four different procedures, HA was obtained after a couple of hours of milling (on an average, 20 h of milling depending on the reaction procedure). The XRD patterns indicate that the grain size is within the range of 29–103 nm. This milling process, used to produce HA, presents the advantage that melting is not necessary and the powder obtained is nanocrystalline with extraordinary mechanical properties. The material can be compacted and transformed in solid ceramic samples. The high efficiency of the process opens a way to produce commercial amount of nanocrystalline HA. Due to the nanocrystalline character of this powder, their mechanical properties have changed and for this reason a pressure of 1 GPa is enough to shape the sample into any geometry. [Copyright &y& Elsevier]

In this paper we did a study of collagen membranes prepared with iron as an impurity. In this study one try to understand the function of the iron in the collagen structure in view of increasing the value of piezoelectric strain tensor element d14. We prepared different samples with different iron doping levels. One has samples doped by immersion in solutions of FeCl2 at 0.1 M and 0.2 M (ColFeCl01 and ColFeCl02) and iron doped directly in solution with Fe2O3 at 5% and 15% (Col7Fe5 and Col7Fe15). We did a study of the Mo¨ssbauer spectroscopy, DC electrical conductivity and the piezoelectric strain tensor element d14, the elastic constant s55, and the dielectric function &epsiv;11 of the samples. The loss factor Q−1 of the samples was also measured using the admittance resonance method. The role played by the iron in the different situations and the consequences for the transport properties is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Silicon nitride has demonstrated to be a potential candidate for clinical applications because it is a non-cytotoxic material and has satisfactory fracture toughness, high wear resistance and low friction coefficient. In this paper, samples of silicon nitride, which were kept into rabbits'' tibias for 8 weeks, and the adjacent bone tissue were analysed by scanning electron microscopy in order to verify the bone growth around the implants and the interaction between the implant and the bone. Bone growth occurred mainly in the cortical areas, although it has been observed that the newly bone tends to grow toward the marrow cavity. Differences were observed between the implants installed into distal and proximal regions. In the first region, where the distance between the implant and the cortical bone is greater than in the proximal region, the osteoconduction process was evidenced by the presence of a bridge bone formation toward the implant surface. The results showed that silicon nitride can be used as biomaterial since the newly bone grew around the implants. [Copyright &y& Elsevier]

Heterostructured thin films of lanthanum ferrite (LFO) and bismuth ferrite (BFO) with different thicknesses were successfully obtained by a soft chemical method. The films were deposited by spin-coating and annealed at 500 °C for 2 h. The XRD pattern confirmed the purity of the thin films, where no additional peaks associated with impurity phases were present. The morphology analysis showed spherical grains with a random size distribution. The grain sizes increased with the number of BFO layers. The average grain size varied from 43 nm to 68 nm. The best dielectric results were obtained for the film with 6 LFO sublayers and 4 BFO top layers, in which the dielectric constant showed low dispersion. Since the capacitance-voltage curve for the film 6-LFO/4-BFO is symmetrical around null voltage, it can be inferred that this heterostructure has few mobile ions and accumulated charges on the film-substrate interface. In this film, polarization remains almost constant during 10 12 cycles before the onset of degradation, which shows the very high resistance of the films to fatigue. Magnetoelectric coefficient measurements of the films revealed the formation of hysteresis loops, and a maximum value of 12 V/cmOe was obtained for the magnetoelectric coefficient in the longitudinal direction; this value is much higher than that previously reported for pure BFO thin films. [ABSTRACT FROM AUTHOR]

Good quality ZnO nanostructures were obtained by the microwave-assisted hydrothermal synthesis, at low reaction temperatures, using zinc acetate as the starting precursor. X-ray diffraction confirmed the crystallinity of the ZnO nanostructures, which resulted free of impurities. Field emission gun scanning electron microscopy analysis revealed that the ZnO nanostructures crystallized at 120 °C were more homogeneous and had a constant diameter along the entire wire length, exhibiting an ideal defect density that favors the gas sensing response. A new ozone gas sensor based on these nanostructures was evaluated at low exposure times (15 s) by recording the change in the film resistance. The ZnO nanostructures showed good sensitivity even at low ozone concentration (100 ppb), and fast response and short recovery time at 200 °C, demonstrating great potential for a variety of applications. Two main effects were observed: the first one is intrinsic to that of the sample, while the second is a consequence of the surface and interface complex cluster defects, which produce extrinsic defects. [ABSTRACT FROM AUTHOR]

Abstract: The sol–gel method was used to prepare a lithium niobiosilicate glass doped with europium ions, 91SiO2–4Li2O–4Nb2O5–1Eu2O3 (% mole). The dried gel was heat-treated between 500 °C and 750 °C and glass ceramics were obtained. X-ray diffraction (XRD), scanning electron microscopy (SEM) and Raman studies show that crystallization starts at temperatures above 600 °C. The LiNbO3 and EuNbO4 nanocrystals were found in the heat-treated samples as corroborated by the structural, morphological and optical properties. Room temperature photoluminescence (PL) studies allow us the identification of multiple Eu-related optical centres and the strongest red 5D0 → 7F2 intraionic transitions occur in the samples heat-treated at 600 °C where the LiNbO3 crystal phase was detected. [Copyright &y& Elsevier]

The objective of this study was to evaluate the effect of different trace mineral supplementation sources in the diet of broiler breeders on their performance and on their progenies. In total, 128 Cobb 500 broiler breeders were distributed according to a completely randomized experimental design in 2 experimental treatments. The control group was fed a diet supplemented with inorganic trace minerals (ITM), while the other group was fed a diet supplemented with reduced levels of trace minerals in the organic form. Eggs were collected when breeders were 35, 47, and 53 wk old. Their progeny (450 hatchlings) were divided according to trace mineral supplementation source from the maternal diet, creating 2 treatments with 16 replicates of 15 birds each. Organic trace mineral (OTM) supplementation improved broiler breeder performance, as shown by higher egg production and better eggshell quality of OTM-fed hens compared with those fed ITM. Egg fertility and hatchability were not influenced by the treatments. As to progeny performance, higher weight gain, and consequently, better feed conversion ratio, were obtained in the 41-day-old progenies of OTM-fed breeders, independently of hen age. Maternal diet trace mineral source did not affect broiler carcass, breast meat, or leg yields. The results of the present study show that supplementing broiler breeder diets with organic trace mineral sources enhances the performance of breeders and their progenies. [ABSTRACT FROM AUTHOR]

Highlights • Amazon basin pastures present higher fungal alpha diversity than forest. • Pasture fungal community dissimilarity is lower than forest leading to biotic homogenization. • Soil physicochemical properties influence fungal composition and diversity. • Deforestation increases phytopathogens and reduces biocontrol fungi incidences. Abstract The advance of livestock towards the hydrographic basin of Mutum-Paraná River, in the state of Rondônia contributes to the conversion of the amazon forest to pasture. This process can decrease the plant diversity, contributing to loss of endemic microorganisms and natural enemies leading to the replacement of native biota by non-native and generalist species. Thereby, we hypothesized that this conversion changes fungal composition, reduce fungal alpha diversity and community dissimilarity and increase the incidence of potential phytopathogenic genera at pasture soils compared to forest. Soil of 10 sampling points from forest and 10 from pasture were collected at the Mutum-Paraná River basin. Via ITS amplicon sequencing of the total soil DNA, differences in composition and in the taxonomic diversity between the two environments were addressed. The phylum Ascomycota predominated in both forest and pasture. Basidiomycota presented lower percent in both, but was higher in pastures. Zygomycota and Glomeromycota presented opposite tendencies, the first being predominately present in forest and the second only present in pasture with low incidence. The fungal diversity was higher in pasture soils, contrasting our hypothesis. There were also significant correlations between soil physicochemical properties and fungal community. The reduction of the dissimilarity in pasture was confirmed and this signalized for a biotic homogenization. In addition, higher incidence of potential phytopathogenic fungi was observed in pasture. These results contribute to a better understanding of how fungal communities are driven by forest-to-pasture conversion. [ABSTRACT FROM AUTHOR]

The wastewater from oil production can be exceptionally saline and contain a complex mixture of hydrocarbons, many of which are highly toxic. This study aimed to identify and characterize 141 halophilic bacteria isolated from production water and activated sludge from Marine Terminal Almirante Barroso (Brazil) and evaluate their potential for biosurfactant production and biodegradation of distinct petroleum hydrocarbons. Sequencing and phylogenetic analysis of the 16S rRNA gene revealed that the halophilic bacteria retrieved are distributed among 20 genera and four phyla (Proteobacteria, Firmicutes, Actinobacteria and Flavobacteria). RAPD fingerprinting was used to differentiate isolates at the infra-specific level, revealing 79 different genetic profiles. GC-MS analysis carried out with eight strains confirmed their ability to efficiently degrade alkanes and aromatic compounds under halophilic conditions, with preference for aromatic degradation. Eleven strains showed significant ability for reduction of the surface tension (from 72 to 40 mN/m) and for emulsification (up to 71%) of four different types of oils (mineral, soybean, diesel and kerosene). Results gathered in this study demonstrate a high taxonomic and genetic diversity of the halophilic bacterial strains isolated from the oil terminal samples and an outstanding potential for further use in biotechnological processes such as biosurfactant production or bioremediation. [ABSTRACT FROM AUTHOR]