Eimeria vitellini n. sp. (Apicomplexa: eimeriidae) from the brazilian toucan Rhamphastos vitellinus vitellinus Lichtenstein (Aves: Picicformes: Rhamplastidae)

Eimeria vitellini n. sp. is described from the faeces of the Rhamphastos v. vitellinus. Oocysts broadly ellipsoidal to oval (egg-shaped), 22,6 x 18.3 (20.0-25.0 x 16.3-22.5) micronm, shapeindex (length/width) 1.2 (1.1-1.1). Oocyst wall a single colourless layer about 0.5 micronm thick, becoming thinner at one ectremity, at which point the oocyst usually ruptures. No oocyst residuum, but 1 or 2 small polr bodies of about 1.0-1.5 x 0.5-1.0 micronm. Sporocysts ellongated ellipsoid (pearshaped), 14.3 x 7.5 (13.8-15.0 x 6.9-7.5) micronm, shape-index (1.9 (1.8-2.0), with a thin colourless wall bearing a very delicate Stieda body: a conspicuous sub-Stieda body is present. Sporozoites with anterior and posterior regractile bodies and strongly recurved around a bulky, compact sporocyst residuum composed of relatively fine granules and spherules.

Observations on some Avian Coccidia (Apicomplexa: Eimeriidae) in Amazonian Brazil

Oocysts of Eimeria porphyrulae n. sp. are described in faeces of Porphyrula martinica (Aves: Gruiformes: Rallidae). They are ellipsoidal to oval, 22.4 x 17.7 (20.0-23.7 x 16.2-18.7) µm, shape-index (length/width) 1.3. Oocyst wall about 1.25 µm thick, colourless, with two layers: inner one prominently striated. Micropyle and sub-micropylar granule present: no oocyst residuum. Sporocysts 17.5 x 9.0 (17.0-19.0 x 8.0-10.0) µm, shape-index 1.9, with inconspicuous Stieda/sub-Stieda bodies. Sporocyst residuum of scattered granules, sometimes a compact mass: sporozoites with two refractile bodies. Eimeria crypturelli n. sp. is described in faeces of Crypturellus soiu (Tinamiformes: Tinamidae). Oocysts ellipsoidal-oval, 20.75 x 14.5 (17.5-25.0 x 11.25-21.25) µm, shape-index 1.4. Oocysts wall about 1.25 µm thick and bi-layered: inner layer faintly striated. Micropyle present, with oocyst residuum immediately below: single polar body rarely present. Sporocysts 13.0 x 7.5 (12.5-13.75 x 7,5-8.1) µm, shape-index 1.7, with a Stieda body but seemingly no sub-Stieda. Sporocyst residuum compact: sporozoites with two refractile bodies. Isospora cacici n. sp. is recorded from faeces of Cacicus cela cela (Passeriformes: Icteridae). Oocysts subspherical-spherical, 26.5 x 23.7 (22.5-27.5 x 20.0-26.2) µm, shape-index 1.1. Wall a single, colourless layer about 1.5 µm thick. No micropyle or oocyst residuum: 1-2 polar bodies. Sporocysts ellipsoidal, 17.7 x 12.5 (17.5-18.75 x 11.25-13.75) µm, shape-index 1.4, with pronounced Stieda/sub-Stieda bodies: residuum compact and sporozoites with two refractile bodies. Isospora thraupis n. sp. is described from faeces of Thraupis palmarum melanoptera (Passeriformes: Thraupidae). Oocysts subspherial-spherical, 19.9 x 19.0 (18.7-21.2 x 18.75-20.0) µm, shape-index 1.0. Wall about 0.6 µm thick, smooth, colourless and a single layer: no micropyle, oocyst residuum or polar bodies. Sporocysts 14.2 x 9.2 (13.7-16.2 x 8.7-10.0) µm, shape-index 1.5: Stied/sub-Stieda bodies inconspicuous. Residuum compact: sporozoites with two refractile bodies.

Identification of Mycobacteria by Thin Layer Chromatographic Analysis of Mycolic Acids and Conventional Biochemical Method: Four Years of Experience

Mycolic acids analysis by thin-layer chromatography (TLC) has been employed by several laboratories worldwide as a method for fast identification of mycobacteria. This method was introduced in Brazil by our laboratory in 1992 as a routine identification technique. Up to the present, 861 strains isolated were identified by mycolic acids TLC and by standard biochemical tests; 61% out of these strains came as clinical samples, 4% isolated from frogs and 35% as environmental samples. Mycobacterium tuberculosis strains identified by classical methods were confirmed by their mycolic acids contents (I, III and IV). The method allowed earlier differentiation of M. avium complex - MAC (mycolic acids I, IV and VI) from M. simiae (acids I, II and IV), both with similar biochemical properties. The method also permitted to distinguish M. fortuitum (acids I and V) from M. chelonae (acids I and II) , and to detect mixed mycobacterial infections cases as M. tuberculosis with MAC and M. fortuitum with MAC. Concluding, four years experience shows that mycolic acids TLC is an easy, reliable, fast and inexpensive method, an important tool to put together conventional mycobacteria identification methods.

Characterization of soil structure and porosity under long-term conventional tillage and no-tillage systems

Different management systems tend to modify soil structure and porosity over the years. The aim of this study was to study modifications in the morphostructure and porosity of dystroferric Red Latosol (Oxisol) under conventional tillage and no-tillage over a 31- year period. The study began with the description of soil profiles based on the cropping profile method, to identify the most compact structures, define sample collection points for physical and chemical analysis, and determine the water retention curve. A forest soil profile was described and used as reference. The results showed that, under conventional tillage, the microaggregate structure of the Oxisol was fragmented between 0 and 0.20 m, and compact (bulk density = 1.52 Mg m-3) in the sub-surface layer between 0.20 and 0.50 m. Under no-tillage, the structure became compacted (bulk density = 1.40 Mg m-3) between 0 and 0.60 m, but contained fissures and biopores. The volume of the class with a pore diameter of > 100 µm under no-tillage was limited, but practically non-existent in the conventional management system. On the other hand, the classes with a pore diameter of < 100 µm were not affected by the type of soil management system.

Attributes of irrigated rice and soil solution as affected by salinity levels of the water layer

In the State of Rio Grande do Sul, Brazil, flooded rice fields using Patos Lagoon as the source of water for irrigation are subject to be damaged by salinity, since this source is bound to the sea on its southern end. The sensitivity of rice is variable during plant development, being higher in the seedling and reproductive periods. However, there is not enough information about the behavior of plants under salt stress during the course of its development, especially in the vegetative stage. This study evaluated the effect of different levels of salinity of irrigation water on the salinity of soil solution over time and on some plant attributes, during the vegetative stage of rice. The study was conducted in a greenhouse, where seeds of the variety IRGA 424 were sown in pots and irrigated with water with electrical conductivity (ECi) levels of: 0.3, 0.75, 1.5, 3.0 and 4.5 dS m-1; from the tillering initiation (V4) until the panicle initiation (PI). The evaluations made were the electrical conductiviy of soil solution (ECe), the dry biomass of plants and stems, tillering, height and the transpiration of plants. The ECe increased with the ECi over time, and was determined by water transpiration flux in pots. The ECe values at the end of the experiment were high and, in most cases, higher than the critical values for flooded rice. The growth attributes of rice were negatively affected from ECi of 2.0 dS m-1 and ECe of 4.0 dS m-1.

Influence of litter layer removal on the soil thermal regime of a pine forest in a mediterranean climate

The removal of the litter layer in Portuguese pine forests would reduce fire hazard, but on the other hand this practice would influence the thermal regime of the soil, hence affecting soil biological activity, litter decomposition and nutrient dynamics. Temperature profiles of a sandy soil (Haplic Podzol) under a pine forest were measured with thermocouples at depths to 16 cm, with and without litter layer. The litter layer acted as a thermal insulator, reducing the amplitude of the periodic temperature variation in the mineral soil underneath and increasing damping depths, particularly at low soil water contents. At the mineral soil surface the reduction of amplitudes was about 2.5 ºC in the annual cycle and 5 to 6.7 ºC in the daily cycle, depending on the soil water content. When soil was both cold and wet, mean daily soil temperatures were higher (about 1 - 1.5 ºC) under the litter layer. Improved soil thermal conditions under the litter layer recommend its retention as a forest management practice to follow in general.

Rill erosion on an oxisol influenced by a thin compacted layer

The presence of compacted layers in soils can induce subprocesses (e.g., discontinuity of water flow) and induces soil erosion and rill development. This study assesses how rill erosion in Oxisols is affected by a plow pan. The study shows that changes in hydraulic properties occur when the topsoil is eroded because the compacted layer lies close below the surface. The hydraulic properties that induce sediment transport and rill formation (i.e., hydraulic thresholds at which these processes occur) are not the same. Because of the resistance of the compacted layer, the hydraulic conditions leading to rill incision on the soil surface differed from the conditions inducing rill deepening. The Reynolds number was the best hydraulic predictor for both processes. The formed rills were shallow and could easily be removed by tillage between crops. However, during rill development, large amounts of soil and contaminants could also be transferred.

Organic Matter Fractions and Quality of the Surface Layer of a Constructed and Vegetated Soil After Coal Mining. I - Humic Substances and Chemical Characterization

After open coal mining, soils are &#8220;constructed&#8221;, which usually contain low levels and quality of organic matter (OM). Therefore, the use of plant species for revegetation and reclamation of degraded areas is essential. This study evaluated the distribution of carbon (C) in the chemical fractions as well as the chemical characteristics and humification degree of OM in a soil constructed after coal mining under cultivation of perennial grasses. The experiment was established in 2003 with the following treatments: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactilon (T3), Urochloa brizantha (T4), bare constructed soil (T5), and natural soil (T6). In 2009, soil samples were collected from the 0.00-0.03 m layer and the total organic carbon stock (TOC) and C stock in the chemical fractions: acid extract (CHCl), fulvic acid (CFA), humic acid (CHA), and humin (CHU) were determined. The humic acid (HA) fraction was characterized by infrared spectroscopy and the laser-induced fluorescence index (ILIF) of OM was also calculated. After six years, differences were only observed in the CHA stocks, which were highest in T1 (0.89 Mg ha-1) and T4 (1.06 Mg ha-1). The infrared spectra of HA in T1, T2 and T4 were similar to T6, with greater contribution of aliphatic organic compounds than in the other treatments. In this way, ILIF decreased in the sequence T5>T3>T4>T1>T2>T6, indicating higher OM humification in T3 and T5 and more labile OM in the other treatments. Consequently, the potential of OM quality recovery in the constructed soil was greatest in treatments T1 and T4.

Organic Matter Fractions and Quality of the Surface Layer of a Constructed and Vegetated Soil After Coal Mining. II - Physical Compartments and Carbon Management Index

Soils constructed after mining often have low carbon (C) stocks and low quality of organic matter (OM). Cover crops are decisive for the recovery process of these stocks, improving the quality of constructed soils. Therefore, the goal of this study was to evaluate the effect of cover crops on total organic C (TOC) stocks, C distribution in physical fractions of OM and the C management index (CMI) of a soil constructed after coal mining. The experiment was initiated in 2003 with six treatments: Hemarthria altissima (T1), Paspalum notatum (T2), Cynodon dactylon (T3), Urochloa brizantha (T4), bare constructed soil (T5), and natural soil (T6). Soil samples were collected in 2009 from the 0.00-0.03 m layer, and the TOC and C stocks in the physical particle size fractions (carbon in the coarse fraction - CCF, and mineral-associated carbon - MAC) and density fractions (free light fraction - FLF; occluded light fraction - OLF, and heavy fraction - HF) of OM were determined. The CMI components: carbon pool index (CPI), lability (L) and lability index (LI) were estimated by both fractionation methods. No differences were observed between TOC, CCF and MAC stocks. The lowest C stocks in FLF and OLF fractions were presented by T2, 0.86 and 0.61 Mg ha-1, respectively. The values of TOC stock, C stock in physical fractions and CMI were intermediate, greater than T5 and lower than T6 in all treatments, indicating the partial recovery of soil quality. As a result of the better adaptation of the species Hemarthria and Brizantha, resulting in greater accumulation of labile organic material, the CPI, L, LI and CMI values were higher in these treatments, suggesting a greater potential of these species for recovery of constructed soils.

Mecanismo de fotodegradação de compostos orgânicos catalisada por TiO2

Conventional technology used in the treatment of wastewater has been pointed as a major environmental problem for sustainable development, since minimization is not addressed accordingly. Advanced oxidation processes (AOP), based on the formation of hydroxyl radical (•OH), a powerful oxidant agent, have been considered to be a potential technology for the destruction of many toxic compounds. Photocatalysis using solar light, an AOP, has been studied for nearly 20 years and recently attracted great interest as a clean-up technology. However, solar detoxification processes have not yet achieved commercial success. This article presents an overview of reaction mechanisms at the surface of semiconductors used as photocatalysts (specially TiO2), when heterogeneous photocatalysis is used to remove hazardous compounds from contaminated sites.

Study of the optical properties of TeO2-PbO-TiO2 glass system

We describe the preparation and some optical properties of high refractive index TeO2-PbO-TiO2 glass system. Highly homogeneous glasses were obtained by agitating the mixture during the melting process in an alumina crucible. The characterization was done by X-ray diffraction, Raman scattering, light absorption and linear refractive index measurements. The results show a change in the glass structure as the PbO content increases: the TeO4 trigonal bipyramids characteristics of TeO2 glasses transform into TeO3 trigonal pyramids. However, the measured refractive indices are almost independent of the glass composition. We show that third-order nonlinear optical susceptibilities calculated from the measured refractive indices using Lines' theoretical model are also independent of the glass composition.

Estudo por espectroscopia no infravermelho da interação metal-suporte em Pt/TiO2. A influência da adsorção de hidrogênio

The influence of the presence of hydrogen on Pt/TiO2 catalysts submitted to reduction treatment has been studied by FT-IR at room temperature. After submitting to LTR treatment, the hydrogen spillover has been detected and the presence of hydrogen at the bulk is shown to produce a strong absorption in the infrared spectral region. After HTR treatment, the hydrogen is strongly chemissorbed.

Análise por difração de raios x de filmes de óxidos cerâmicos compostos por IrO2/TiO2/CeO2

Independent of the sample form (powder or film), XRD analysis of Ir0,3Ti(0,7-x)Ce xO2, (nominal) mixtures, for x=0, shows the formation of a solid solution phase between IrO2 and TiO2, as well as the rutile phases of IrO2 and TiO2. The presence of the anatase phase of TiO2 is also confirmed. The introduction of 30 mol% CeO2 in the mixture reveals the presence of the CeO2 and Ce2O3 phases, besides the already mentioned ones, in the powder. In the film form, however, an amorphous phase is identified. When all of the TiO2 is substituded by CeO2, for both sample forms, the only phases found are IrO2, CeO2 and Ce2O3. This result suggests cerium oxides are not capable of forming solid solutions with either IrO2 or (Ir,Ti)O2 acting solely as a dispersant matrix for these phases. These results are consistent with the much higher electrochemically active surface area when CeO2 is introduced in the binary Ti/Ir0,3Ti0,7O2 mixture. It was possible to establish a relationship between the electrochemical stability of the supported films and their crystalline structure. The unexpected presence of TiO2 and Ti2O3 in the Ti/Ir0,3Ce0,7O2 (film sample) is attributed to oxidation of the Ti support during the calcination step.

Caracterização textural e estrutural de V2O5/TiO2 obtidos via sol-gel: comparação entre secagem convencional e supercrítica

This work describes a modified sol-gel method for the preparation of V2O5/TiO2 catalysts. The samples have been characterized by N2 adsorption at 77K, x-ray diffractometry (XRD) and Fourier Transform Infrared (FT-IR). The surface area increases with the vanadia loading from 24 m² g-1, for pure TiO2, to 87 m² g-1 for 9wt.% of V2O5. The rutile form is predominant for pure TiO2 but became enriched with anatase phase when vanadia loading is increased. No crystalline V2O5 phase was observed in the catalysts diffractograms. Two species of surface vanadium observed by FT-IR spectroscopy a monomeric vanadyl and polymeric vanadates, the vanadyl/vanadate ratio remains practically constant.