Agronomic performance of common bean in straw mulch systems and topdressing nitrogen rates in no-tillage

ABSTRACTIn no-tillage systems, straw coverage on soil surface is the key to success, and the choice of crops for rotation is crucial to achieve the sustainability and quality that conservation agriculture requires. The objective of this study was to evaluate the agronomic performance of the common bean cultivar IAC Formoso sown in succession to three straw mulch systems (corn alone, corn/Urochloa ruziziensisintercrop and U. ruziziensisalone) and topdress nitrogen rates (0; 40; 80; 120 and 160 kg ha-1N), at the four-leaf stage, three years after the implementation of no-tillage. The experiment was arranged in a randomized block split plot design, with three replications. Common bean highest yields were achieved in succession to U. ruziziensisalone and intercropped with corn. The corn/U. ruziziensisintercrop provided both straw and seed production, allowing for quality no-tillage. Topdressed nitrogen influenced the common bean yield when in succession to corn alone, U. ruziziensisalone and corn/U. ruziziensisintercrop in no-tillage.

Seroprevalence of Helicobacter pylori infection in chronic chagasic patients, and in the rural and urban population from Uberlândia, Minas Gerais, Brazil

As patients with chronic Chagas disease exhibit morphological and functional changes of the stomach (hypomotility and hypochlorhydria), malnutrition, immunological deficiency and high prevalence of peptic disease associated to Helicobater pylori infection, the purpose of this study was to evaluate if the prevalence of H. pylori infection in chronic chagasic is higher than in non-chagasic individuals in the urban and rural population from Uberlândia, MG, Brazil. Serological determination of IgG antibodies to H. pylori was performed using a second-generation ELISA. Thus, 598 people were evaluated: 128 chagasic (CG), 222 non-chagasic living in urban area (U-NCG) and 248 non-chagasic living in rural area (R-NCG). Regarding the age range from 21 to 50 years, the prevalence of H. pylori infection in the CG (85.1%) was significantly higher than in the U-NCG (56.3%, p < 0.01) and the R-NCG (67.4%, p < 0.05). In the patients over 50 years, the prevalence in the CG (86.4%) was similar to the U-NCG (78.8%) and R-NCG (86.1%). Similar results were also found between the U-NCG and R-NCG for all age ranges, with prevalence rates of 29.1% and 35.3% for the age range from 5 to 13 years, and 47.2% and 40% for that from 14 to 20 years, respectively. We conclude that chagasic patients showed a higher seroprevalence of H. pylori infection than non-chagasic individuals, in the age range from 21 to 50 years, and that the prevalence of this infection was similar in the studied urban and rural non-chagasic population.

New approaches in antimalarial drug discovery and development: a review

Malaria remains a major world health problem following the emergence and spread of Plasmodium falciparum that is resistant to the majority of antimalarial drugs. This problem has since been aggravated by a decreased sensitivity of Plasmodium vivax to chloroquine. This review discusses strategies for evaluating the antimalarial activity of new compounds in vitro and in animal models ranging from conventional tests to the latest high-throughput screening technologies. Antimalarial discovery approaches include the following: the discovery of antimalarials from natural sources, chemical modifications of existing antimalarials, the development of hybrid compounds, testing of commercially available drugs that have been approved for human use for other diseases and molecular modelling using virtual screening technology and docking. Using these approaches, thousands of new drugs with known molecular specificity and active against P. falciparum have been selected. The inhibition of haemozoin formation in vitro, an indirect test that does not require P. falciparum cultures, has been described and this test is believed to improve antimalarial drug discovery. Clinical trials conducted with new funds from international agencies and the participation of several industries committed to the eradication of malaria should accelerate the discovery of drugs that are as effective as artemisinin derivatives, thus providing new hope for the control of malaria.

Leptin receptor (Ob-R) mRNA expression and serum leptin concentration in patients with colorectal and metastatic colorectal cancer

The objective of the present study was to investigate the effect of leptin on the progression of colorectal carcinoma to metastatic disease by analyzing the serum leptin concentration and Ob-R gene expression in colon cancer tissues. Tissue samples were obtained from 31 patients who underwent surgical resection for colon (18 cases) and metastatic colon (13 cases) cancer. Serum leptin concentration was determined by an enzyme-linked immunosorbent assay (ELISA) and Ob-R mRNA expression by real-time polymerase chain reaction (RT-PCR) for both groups. ELISA data were analyzed by the Student t-test and RT-PCR data were analyzed by the Mann-Whitney U-test. RT-PCR results demonstrated that mRNA expression of Ob-R in human metastatic colorectal cancer was higher than in local colorectal cancer tissues. On the other hand, mean serum leptin concentration was significantly higher in local colorectal cancer patients compared to patients with metastatic colorectal cancer. The results of the present study suggest a role for leptin in the progression of colon cancer to metastatic disease without weight loss. In other words, significantly increased Ob-R mRNA expression and decreased serum leptin concentration in patients with metastatic colon cancer indicate that sensitization to leptin activity may be a major indicator of metastasis to the colon tissue and the determination of leptin concentration and leptin gene expression may be used to aid the diagnosis.

Downstream processing of pectinase produced by Aspergillus niger in solid state cultivation and its application to fruit juices clarification

In this work, a protocol for the formulation of an enzyme concentrated product to be applied in fruit juice treatment is described. Downstream processing conditions for the recovery and concentration of pectinases produced by the new strain Aspergillus niger LB-02-SF in solid state cultivation were assessed. The solid-liquid ratio in the extraction step of pectinases recovery from the cultivated media was evaluated and the highest activity was obtained with a solid-liquid ratio of 1:10. The crude extract was concentrated by ultrafiltration and the total pectinase (TP) activity was 73.6-fold concentrated in relation to the crude extract, and a final TP titer of 663 U mL–1 was obtained with 73.7% of recovery yield. KCl and different glycerol concentrations were added to the concentrated extract and the stability of pectinases during the storage at 5°C for 59 weeks was tested. The formulation with 50% w/w glycerol was applied to the treatment of apple and grape juices and the results of these tests were statistically comparable to those obtained with two high-quality commercial preparations.

The US experience in contracting out security and lessons for other countries

The United States has gone further than any country in the "privatization of security". Other countries may find the economic or financial logic in the use of contractors persuasive. The US experience with contracting out security, particularly in Iraq, was problematic, and can serve as a cautionary tale in order that other countries might learn how to avoid the pitfalls.

Particulate bioglass in the regeneration of alveolar bone in dogs: clinical, surgical and radiographic evaluations

Bone loss, either by trauma or other diseases, generates an increasing need for substitutes of this tissue. This study evaluated Bioglass as a bone substitute in the regeneration of the alveolar bone in mandibles of dogs by clinical, surgical and radiological analysis. Twenty-eight adult dogs were randomly separated into two equal groups. In each animal, a bone defect was created on the vestibular surface of the alveolar bone between the roots of the fourth right premolar tooth. In the treated group, the defect was immediately filled with bioglass, while in the control, it remained unfilled. Clinical evaluations were performed daily for a week, as well as x-rays immediately after surgery and at 8, 14, 21, 42, 60, 90 and 120 days post-operative. Most animals in both groups showed no signs of inflammation and wound healing was similar. Radiographic examination revealed a gradual increase of radiopacity in the region of the defect in the control group. In the treated group, initial radiopacity was higher than that of adjacent bone, decreasing until 21 days after surgery. Then it gradually increased until 120 days after surgery, when the defect became undetectable. The results showed that Bioglass integrates into bone tissue, is biocompatible and reduced the period for complete bone regeneration.

Growth and nutrient uptake of coffee seedlings cultivated in nutrient solution with and without silicon addition

In recent years, the application of silicon (Si) in crops, including coffee, has become a common practice. The objective of this study was to assess the silicon uptake by coffee seedlings and its effects on plant growth, water and macro and micronutrient uptake. The research was conducted using nutrient solution in a greenhouse at the Departamento de Fitotecnia da Universidade Federal de Viçosa, in a completely randomized design with two treatments (with and without silicon) and three replications. Each plot consisted of three plants grown in a 800 mL vessel containing the treatment solutions. At every three days, water consumption, the concentration of OH - and the depletion of Si and K were assessed in the nutrient solutions. After 33 days, the plants were assessed with regard to their fresh and dry weight of leaves, roots and stem, shoot height and total length of the plant (shoot and root). Number of leaves and internodes, and the content and accumulation of silicon, macro, and micronutrients were also determined. The consumption of water, the amount of potassium uptake and, biomass accumulation were greater in plants grown in solution without silicon addition. However, the concentration of OH- in the solution and the amount of silicon uptake were greater in plants grown in solution with added silicon. Silicon accumulation was greater in leaves than in stem and roots. Silicon decreased coffee plant accumulation of phosphorus, potassium, calcium, zinc, copper and iron.

Adventitious rooting in cuttings of croton and hibiscus in response to indolbutyric acid and humic acid

Adventitious rooting of ornamental plants can be accelerated by the application of growth regulators, such as auxin. Humic acids, organic matter in soil and organic compounds also have a biostimulant effect. This work evaluated the rooting in cuttings of croton (Codianeum variegatum L. Rumph) and hibiscus (Hibiscus rosa-sinensis L) in response to the application of different concentrations of indolbutyric acid (IBA) and humic acid (HA). The experiment was carried out in a greenhouse. Apical stem cuttings were treated with solutions at concentrations of: 0, 250, 500, 1000, 2000 mg L-1 IBA and 0, 10, 20, 30, 40 mmol L-1 HA carbon isolated from vermicomposting. Forty-five days after the applications, the cuttings were removed from the pots containing carbonized rice hull and the following variables were measured: rooting number, length and width of leaves, fresh and dry matter of root and aerial part and root area. The results were subjected to analysis of variance and the qualitative and quantitative effects of the treatments were compared by contrast and regression, respectively. Regression equations were used to determine the maximum efficiency level of root dry matter according to IBA and HA. Higher accumulation of root dry matter was recorded for the treatments with the doses 579 mg L-1 IBA and 14 mmol L-1 HA and 970 mg L-1 IBA and 50 mmol L-1 HA for root cuttings of croton and hibiscus, respectively. It was found that the application of eiher IBA or HA at the indicated doses accelerates rooting in cuttings of croton and hibiscus and contributes to the formation of vigorous plants.

No-till corn performance in response to P and fertilization modes

No-tillage systems provide soil changes that affect nutrient dynamics, hence, changing rates and forms of fertilizer application. This study aimed to evaluate the effect of phosphorus (P) and modes of nitrogen (N) and P application in corn under long-term no-tillage in a clayey Oxisol. Two experiments were carried out in the same experimental area and in the same year, in a randomized blocks design with four replications. In experiment I, the treatments consisted of five doses of phosphorus (0, 40, 80, 120 and 160 kg ha-1 of P2O5) applied in the sowing furrow. In experiment II, the treatments consisted of the N and P application modes (topdressing, in the sowing furrow and control - without N and P). Experiment I evaluated the root length, P uptake and grain yield and, the Experiment II, the firing height and yield. The P rates provided linear increases in root length in the 0-10 cm layer, P uptake and grain production. The different modes of application provided differences in the firing height and corn yield. The control treatment (0 kg ha-1 of N and P) provided the highest firing height, superior than those of topdressing and application in the furrow, which were not significantly different. The topdress application of N and P provided an increase in corn yield that exceeded 16 and 42% of the application in the furrow and the control, respectively. Thus, the results confirmed that increasing rates of P2O5, in soil with high initial P content, influence positively corn production factors, but with little significant responses, and the topdress application of N and P on soil with high P content, without water restriction, provided increased grain yield in relation to the application in the furrow.

The institutional configuration of sport policy in Brazil: organization, evolution and dilemmas

Brazil has become the center of the spotlight of the whole world recently, amongst many other reasons, one of them was because it was chosen to host a series of mega sporting events - Pan American Games in 2007, Confederations Football Cup in 2013, Fifa Football World Cup 2014 Games and 2016 Olympic and Paralympic Games in 2016. However, little is known about the country's administrative governmental structure focused on sport policy. The available studies focus their analysis on the sport policies content, but not on the arrangement of its structural decision-making. The main aim of this article is indeed to describe, based on official documentation, the evolution and the current arrangements of the government responsible for the administrative structure for the planning and implementation of sports policies in Brazil. Thus, we tried to list the main problems arising from the organization of the Brazilian sports' management. These problems are: (1) inappropriate institutional structure in terms of human resources and obstacles to participation by other social actors beyond the officials (parliament and members of the Ministry of Sports) in the sports policy; (2) disarticulation between public institutions generating redundancies and conflicts of jurisdiction due to the poor division of labor between bureaucracy agencies; and (3) inadequate planning proved by the lack of organization of some institutions, and by the lack of assessment and continuity of public policies over time. Therefore, we must emphasize those problems from above, and due to these administrative arrangements, Brazilian sports' policy has big challenges in the sport development in this country, which includes the creation of a national "system" for sports and a priority investment in sport education.

Typhoid fever in children of low and high socieconomic strata: comparison of hygiene habits

The relationship between the hygienic habits of children who had typhoid fever (TF) who had recently begun attending school and their family group, is assessed. It is supposed that children, independently of their SES, acquired TF because of inadequate habits which facilitated the oral-fecal cycle. The sample was formed of 40 child-mother dyads: 20 of low SES (group A) and 20 of high SES (group B), the child of each of which had had TF. Results showed that the hygienic habits of children with respect to the oral-fecal cycle, their perception of school toilet cleanliness as well as the mothers' explanation of their children's hygienic habits is very similar in the two groups. The importance of these results is that the SES is seem to be irrelevant in the case of TF but that the hygienic habits of the children are of importance. Public health policy should be modified to include the teaching of proper hygienic habits (oral-fecal cycle).

Infant mortality and low birth weight in cities of Northeastern and Southeastern Brazil

OBJECTIVE: To compare estimates of low birth weight (LBW), preterm birth, small for gestational age (SGA), and infant mortality in two birth cohorts in Brazil. METHODS: The two cohorts were performed during the 1990s, in São Luís, located in a less developed area in Northeastern Brazil, and Ribeirão Preto, situated in a more developed region in Southeastern Brazil. Data from one-third of all live births in Ribeirão Preto in 1994 were collected (2,839 single deliveries). In São Luís, systematic sampling of deliveries stratified by maternity hospital was performed from 1997 to 1998 (2,439 single deliveries). The chi-squared (for categories and trends) and Student t tests were used in the statistical analyses. RESULTS: The LBW rate was lower in São Luís, thus presenting an epidemiological paradox. The preterm birth rates were similar, although expected to be higher in Ribeirão Preto because of the direct relationship between preterm birth and LBW. Dissociation between LBW and infant mortality was observed, since São Luís showed a lower LBW rate and higher infant mortality, while the opposite occurred in Ribeirão Preto. CONCLUSIONS: Higher prevalence of maternal smoking and better access to and quality of perinatal care, thereby leading to earlier medical interventions (cesarean section and induced preterm births) that resulted in more low weight live births than stillbirths in Ribeirão Preto, may explain these paradoxes. The ecological dissociation observed between LBW and infant mortality indicates that the LBW rate should no longer be systematically considered as an indicator of social development.

Body dissatisfaction in Brazilian schoolchildren: prevalence and associated factors

OBJECTIVE: To examine the prevalence of body dissatisfaction and associated factors in 8- to 11-year-old schoolchildren. METHODS: A cross-sectional study including children aged 8- to 11-years enrolled in public and private schools in Porto Alegre, Southern Brazil, was carried out from August to December, 2001. A total of 901 subjects were selected through cluster sampling. Participants answered a questionnaire aimed at measuring body dissatisfaction and self-esteem and questions about family and social pressures on weight change. Height and weight were measured. The relationship between body dissatisfaction and the variables studied was measured by logistic regression. RESULTS: The prevalence of body dissatisfaction was 82%. Fifty-five percent of the girls wanted a thinner body size, and 28% desired a larger one; the estimates for the boys were 43% and 38%, respectively. Children with the lowest self-esteem (OR=1.80; 95% CI: 1.13-2.89) and who thought their parents (OR=6.10; 95% CI: 2.95-12.60) and friends (OR=1.81; 95% CI: 1.02-3.20) expected them to be thinner showed a higher chance of presenting body dissatisfaction. CONCLUSIONS: Body dissatisfaction was highly prevalent among the evaluated schoolchildren, especially in those with lower self-esteem and who thought their parents and friends expected them to be thinner.

Ethical dilemmas in scientific publication: pitfalls and solutions for editors

Editors of scientific journals need to be conversant with the mechanisms by which scientific misconduct is amplified by publication practices. This paper provides definitions, ways to document the extent of the problem, and examples of editorial attempts to counter fraud. Fabrication, falsification, duplication, ghost authorship, gift authorship, lack of ethics approval, non-disclosure, 'salami' publication, conflicts of interest, auto-citation, duplicate submission, duplicate publications, and plagiarism are common problems. Editorial misconduct includes failure to observe due process, undue delay in reaching decisions and communicating these to authors, inappropriate review procedures, and confounding a journal's content with its advertising or promotional potential. Editors also can be admonished by their peers for failure to investigate suspected misconduct, failure to retract when indicated, and failure to abide voluntarily by the six main sources of relevant international guidelines on research, its reporting and editorial practice. Editors are in a good position to promulgate reasonable standards of practice, and can start by using consensus guidelines on publication ethics to state explicitly how their journals function. Reviewers, editors, authors and readers all then have a better chance to understand, and abide by, the rules of publishing.