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Aluminum (Al) is an ubiquitously present element in soil; it is considered as a major problem in crop production that affects plant growth and development on acid soils. The aim of this work was to determine the germination parameters, to quantify the water status and growth, to assess the Al accumulation, and antioxidant enzyme activities in plants to evaluate the stress exerted by aluminum in Cucumis sativus L. For germination test, increasing doses of Al were used (0, 200, 500, 1,000, and 2,000 μM). Results showed that germination was stimulated with 500 of Al. Aluminum effects on development were studied by treating the plants with different concentrations of Al (100, 200, 300, and 500 µM, Al) during 45 days. As regards to the plant's growth, water content, and dry biomass production there was a slight increase. On the other hand, the activities of the antioxidant enzymes were disturbed by aluminum stress. Data indicate that the catalase (CAT) activity showed a decrease in the different parts of the plant. However, guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) activities were significantly stimulated. Studying the effects of Al‐induced stress allowed us to conclude that cucumber has a high ability to accumulate this element in the roots.

Sewage sludge is considered as a main product obtained from urban liquid effluents that are discharged into sanitation systems of wastewater treatment plants. The aim of this work was to reuse it as compost, after the dehydration process, to replace the amendment applied in agriculture and also to reduce the environmental pollution caused by solid wastes. To justify our biotechnological approach, nutrient characterization of the composted dewatered sewage sludge was carried out and compared to cattle manure. The contents of N, P, K, and the organic matter are 3.67, 5.64, 6.60 g·kg-1 dry matter (DM), and 70%, respectively, in compost and 3.1, 1.6, 3.0 g·kg−1 DM, and 55%, respectively, in manure. Fertilization tests with composted dewatered sewage sludge and cattle manure were performed on Pelargonium inquinans. Monitoring the length of the first internodes showed an improvement of 4.2 mm in the length in compost plants with a development of 22.8 buds and 8.2 flower buds (19.4 buds and 4.4 flower buds developed in manure plants). It appears that the intake of composted dewatered sewage sludge ensures better growth for the studied plant due to its richness in nutrients, which confirms the beneficial effect of composting sewage sludge on plant cultivation.

Barium (Ba) is a nonessential element that can cause several deleterious effects in most organisms. Elevated Ba concentrations can be toxic for plants and may affect growth and disturbances in homeostasis. This study aimed to evaluate the Ba stress, the plant‐tolerance limits, and the detoxification strategy adopted by Cucumis sativus L. The effect of Ba on seed's germination and vegetative development of this species was evaluated. For germination test, different Ba concentrations were used (0, 200, 500, 1,000, and 2,000 μM). Results showed that germination was stimulated with 500 and 2,000 µM of Ba. The toxicity effect on plant development was studied by treating the plants with increasing doses of Ba (100, 200, 300, and 500 μM) during 45 days. Shoot and root dry biomass production decreased significantly with elevated Ba concentrations, although water content enhanced in the roots. The concentration of Ba, 500 µM, induced high Ba accumulation in shoots and roots (9 times higher than in the control plants). Moreover, results showed that catalase, guaiacol peroxidase, and ascorbate peroxidase activities were stimulated in the different tissues of cucumber plants which highlight the occurring of an oxidative damage through Ba treatments and the involvement of the plant enzymatic antioxidant defense system., Barium treatments improve the germination percentage of cucumber seeds. Barium‐induced stress inhibits the growth of shoots and roots of cucumber plants. Water content increase in cucumber roots with elevated doses of barium. In cucumber plants barium accumulation occurs in both parts: shoots and roots. Barium treatments induce an increase in the activity of antioxidant enzymes (CAT, APX, and GPX).

Halimione portulacoides plants were exposed to dissolved cerium (Ce) in a hydroponic medium for five days. Ce accumulation in plants followed the metal's increase in the medium although with a very low translocation factor (TF 0.01) between roots and shoots. Ce median concentrations in roots were 586, 988 and 1103 μg/g (dry wt.), while in shoots the median values reached 1.9, 3.5 and 10.0 μg/g (dry wt.), for plants exposed to 300, 600 and 1200 μg/L of Ce, respectively. No significant differences occurred in the length of roots and shoots among treatment groups, albeit plants exposed to the highest Ce concentration showed a clear loss of turgor pressure on the fifth day. An increase of hydrogen peroxide and malondialdehyde levels were observed in the plant shoots at 1200 μg/L of Ce. The highest concentration also triggered an answer by the shoots' antioxidant enzymes with a decrease in the activity of superoxide dismutase and an increase in peroxidase. However, no significant change in catalase activity was observed, compared to the control group, which may indicate that peroxidase played a more crucial role against the oxidative stress than catalase. Combined results indicate that H. portulacoides was actively responding to a toxic effect imposed by this higher Ce concentration. Nevertheless, changes in normal environmental conditions, may increase the bioavailability of Ce, while in areas where acid mine drainage may occur, the highest Ce concentration tested in this study may be largely exceeded, placing the sustainability of halophytes and estuarine marshes at risk.

São Domingos sulfide mine was shut down more than 50 years ago leaving behind eroded and depositional surfaces due to acid mine drainage (AMD). The aim of this study was to assess six selected sites subjected to AMD, considered phytotoxic regions characterized by vegetation scarcity. Two main criteria, nature and composition of soluble fractions and total chemistry of surficial products related to jarosites presence, enabled to set up an overall dichotomy between superficial proximal/discharge and distal/sedimentation areas. Wet and dry sieving results comparison revealed that samples have a predominant sandy texture and lithic (phyllite, quartzite and volcanic country rocks) composition. Quartz, and subordinate feldspar enrichment is also detected in the coarse silt fraction. The results also suggest that the materials under study, when subjected to the local torrential hydrologic regime, have a high mechanical vulnerability, facilitating erosion and mud transport, both critical for vegetation support, and triggering contamination transfer and dispersion. The vicinity and ground-level surfaces of discharging areas are enriched in the jarosite group minerals whereas the sedimentation ones present hypersaline aluminous tendency. The formation of jarosite is considered as an efficient positive environmental contribution to metals and metalloids sequestration/immobilization. The remediation/revegetation solutions to be adopted in each location must have into consideration these differentiating aspects.

International audience; Triatomine bugs are considered nocturnal insects that feed on the blood of vertebrates and remain hidden inside narrow shelters during daylight hours. Nevertheless, it is not clear whether these insects become active and leave their shelters on a daily basis, less frequently or, even fortnightly. Activity patterns were studied in Rhodnius prolixus Stål, 1859 (Hemiptera: Triatominae) associated with shelters to evaluate whether the decision to leave a shelter depends on bug starvation and the presence of host odours. Experiments were conducted with groups of 5th instar nymphs released in an experimental arena offering an artificial shelter consisting of a piece of corrugated cardboard positioned in its centre. Results indicate that host odours promoted a significant increase in shelter related activity, i.e. shelter-leaving or entering movements, and also in bug locomotion. This increase could only be observed with bugs starved for 30 or 60 days, but not for 21 days. Most R. prolixus nymphs that left shelters and engaged in locomotory activity were starved and in the presence of host odours. Even though R. prolixus is mostly considered a very active and “aggressive” triatomine, our results contradict this perspective and suggest that its main strategy regarding hosts is to wait and carefully evaluate feeding chances before becoming exposed. This behavioural strategy might have arisen through their evolution in palm trees in association with a diverse fauna that may impose predation risks.

Phragmites sp. is present worldwide in treatment wetlands though the mechanisms involved in the phytoremediation remain unclear. In this study a quantitative proteomic approach was used to study the prompt response and adaptation of Phragmites to the textile dyeing pollutant, Acid Orange 7 (AO7). Previously, it was demonstrated that AO7 could be successfully removed from wastewater and mineralized in a constructed wetland planted with Phragmites sp. This azo dye is readily taken up by roots and transported to the plant aerial part by the xylem. Phragmites leaf samples were collected from a pilot scale vertical flow constructed wetland after 0.25, 3.25 and 24.25 h exposure to AO7 (400 mg L− 1) immediately after a watering cycle used as control. Leaf soluble protein extraction yielded an average of 1560 proteins in a broad pI range (pH 3–10) by two-dimensional gel electrophoresis. A time course comparative analysis of leaf proteome revealed that 40 proteins had a differential abundance compared to control (p

An alternative approach for plant complex protein extracts pre-purification by in-solution isoelectric focusing in non-denaturing conditions is presented. The separation of biologically active proteins, in narrow ranges of isoelectric point (pI) was obtained by a modified OFFGEL electrophoresis. Two different water-soluble protein extracts from Phragmites leaves were fractionated into 24 fractions within a 3–10 pI range at 10 °C in the absence of denaturing/reducing agents. One-dimensional electrophoretic analysis revealed different protein distribution patterns and the effective fractionation of both protein extracts. Peroxidase activity of each fraction confirmed that proteins remained active and pre-purification occurred. Biological triplicates assured the needed reproducibility.

Phytoremediation of a xenobiotic, like a textile azo-dye, acid orange 7 (AO7) in a pilot constructed wetland (CW), is feasible even for very high concentrations ([AO7] = 748 ± 42 mg l−1). Removal efficiencies of approximately 68 ± 8%; 69 ± 8% and 67 ± 4% were obtained for [AO7], COD and TOC, respectively. A study of the gene-expression for the most widely used plant in CWs (Phragmites australis) while integrated in the AO7 wastewater treatment was developed. A comparative transcriptomic (mRNA) analysis of reactive oxygen species (ROS) scavenging enzymes, namely catalase (CAT) isoforms, glutathione peroxidase (GPX) and superoxide dismutase (SOD) isoforms of P. australis, was carried out without xenobiotic (non-stress conditions) and in response to the presence of AO7 (high oxidative stress conditions). CATs, GPX and SODs primers design was obtained using published genes of conserved motives from plants of the Poaceae family. The results obtained indicated that AO7 was a chemical stressor agent when in contact with P. australis root system, as foliar gene expression of ROS-scavenging enzymes that belong to plant antioxidative defence system was activated. This constitutes an indirect methodology that enables the correlation between P. australis ROS production induced by AO7 through the measurement of the mRNA accumulation.

This study focuses on the evaluation of the adequacy and sustainability of a constructed wetland (CW), with vertical flow (VF) design to treat a strongly coloured textile wastewater. Secondly an accidental AO7 overloaded discharge (700 mg l−1) was studied. A set of three similar VFCW beds (3 × 1 m2), operating in series, allowed also the efficient treatment of the AO7 heavy loaded wastewaters. The treated effluent quality enables water reuse for irrigation purposes or within the process.

Background Bipolar disorder (BD) diagnosis is based on specific set of mood and behavioural symptoms although they also exhibit cognitive dysfunction. Immune/inflammatory mechanisms have been implicated in the pathophysiology of BD. Objective To investigate whether cognitive functioning is associated with clinical parameters and immune profile in patients with BD in remission. Methods Twenty patients with BD type I in remission (15/20 female; age [mean ± SD] 43.80 ± 11.72 years; years of education [mean ± SD] 12.40 ± 3.39) and 25 healthy controls (16/25 female; age [mean ± SD] 43.52 ± 11.72 years; years of education [mean ± SD] 11.16 ± 2.66) matched for age, gender, and years of education were enrolled in this study. Subjects were evaluated with the Mini-Plus; Young Mania Rating Scale; Hamilton Depression Rating Scale; and with Brief Assessment of Cognition in Affective Disorders a comprehensive test battery to evaluate visuomotor, immediate affective and non-affective memory, verbal fluency, delayed affective and non-affective memory, inhibition, and problem solving domains. We assessed IL2, IL4, IL6, IL10, IL17, INF, TNF and its soluble receptors in plasma by flow cytometry. Results Patients with BD exhibited poorer performance on all cognitive domains in comparison with controls. Patients with BD also had high levels of soluble TNF receptors, and Th1/Th2/Th17 cytokines (p Conclusion Our data suggest that inflammatory dysfunction might contribute to the cognitive impairment in BD.

Avaliou-se o efeito da suplementação de eletrólitos sobre o desempenho de frangos, utilizando bicarbonato de sódio (NaHCO3) e cloreto de potássio (KCl) para ajuste do balanço eletrolítico da dieta (BED) com duas porcentagens de proteína bruta (PB). Utilizaram-se 800 frangos machos, alojados em 20 boxes, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos, cinco repetições e 40 aves por unidade experimental. Os tratamentos foram: dieta basal; dieta sem redução de PB suplementada com eletrólitos para ajuste do BED para 250mEq/kg; dieta com redução de PB, sem suplementação de eletrólitos; e dieta com redução de PB, com eletrólitos para ajuste do BED para 250mEq/kg. Foram avaliados: consumo da dieta, peso final, ganho de peso, ganho de peso médio diário, conversão alimentar e calórica e eficiência de utilização de nitrogênio e lisina nas fases de sete a 21 e de sete a 42 dias. Não se observaram diferenças (P>0,05) no consumo da dieta. A correção do BED com menor teor de PB melhorou (P

Data mining techniques are becoming increasingly more popular as a reasonable means to collect summaries from the rapidly growing datasets in many areas. However, as the size of the raw data increases, parallel data mining algorithms are becoming a necessity. In this paper, we present a run-time support system that was designed to allow the efficient implementation of data-mining algorithms on heterogeneous distributed environments. We believe that the runtime framework is suitable for a broader class of applications, beyond data mining. We also present a parallelization strategy that is supported by the run-time system. We show scalability results of three different data-mining algorithms that were parallelized using our approach and our run-time support. All applications scale almost linearly up to a large number of nodes.

Grid environments are becoming cost-effective substitutes to supercomputers. Datacutter is one of several initiatives in creating mechanisms for applications to efficiently exploit the vast computation power of such environments. In Datacutter, applications are modeled as a set of communicating filters that may run on several nodes of a computational grid. To achieve high performance, a number of transparent copies of each of the filters that comprise the application need to be appropriately placed on different nodes of the grid. Such task is carried out by a scheduler which is the focus of this work. We present LPSched, a scheduler for Datacutter applications which uses linear programming to make decisions about the number of copies of each filter as well as the placement of each of the copies across the nodes. LPSched bases its decisions upon the performance behavior of each filter as well as the resources currently available on the grid.

The main purpose of the present study was to investigate the occurrence of antibodies against T. gondii and N. caninum in captive maned wolves from Brazil, considering that little information is available at the literature about infections by these parasites in this wild animal. Serum samples were obtained from 59 maned wolves originated from six zoos and from one ecological reserve of the southeastern and midwestern regions of Brazil. To detect IgG antibodies against T. gondii, an ELISA protocol was used and the results were expressed as ELISA reactivity indexes (EI). Serology for N. caninum was carried out by indirect fluorescent antibody test (IFAT) and cut-off titers were established at 1:25 dilution. From the total of the analyzed samples, 44 (74.6%) were seropositive for T. gondii and only 5 (8.5%) for N. caninum. Seropositivity for T. gondii ranged from 0 to 100% in the seven different origin locals, with rates over 50% among the six zoos, whereas no positivity was found in the samples from ecological reserve. For N. caninum, seroprevalence varied from 0 to 50% in the different locals, with the highest rates also detected in zoos. Seroprevalence for T. gondii was strongly related with age, with rates significantly higher among adult wolves (91.7%) when compared to newborn or young animals. Seropositive samples for N. caninum were found predominantly in adult wolves. For both parasites, seroprevalence did not show a significant distinction in relation to gender. Although seroprevalence for T. gondii was significantly higher when compared to N. caninum in the Brazilian captive maned wolves tested, these findings reflect the great exposure of this species to T. gondii and, in lower extension, to N. caninum. Also, the present study demonstrated for the first time the presence of antibodies to N. caninum in wild life from South America.

OBJECTIVE: this study was made with the medical students of the "Universidade Federal de Minas Gerais" (UFMG), to get their social economic profile, and their reasons for studying medicine, choosing the specialty, doing medical residence, and showing preferences for being a liberal professional or a salaried employee. METHODS: In 1997, a study was made comparing UFMG's medical students beginning their clinical practice (5th semester) and those medical students during the internship in the last term of clinical practice. Both groups were given questionnaires for evaluation. RESULTS: The results were similar for both groups and showed that women constituted almost 50% of the students and about 50% of them were from Belo Horizonte, the State capital of Minas Gerais, Brazil, and from small families with less than three children, and whose parents held a college degree. These students passed the college entrance exams on their first try. Two thirds of their families had income of about 10 to 50 Brazilian minimum wages, and approximately 12% of the families had an income of less than 10 minimum wages. The majority of the students decided to study medicine for altruism or vocational reason; very few (