1,492 research outputs found
Exposição de embriões de Danio rerio a Nano-TiO2 sob diferentes condições de iluminação.
Resumo: As nanopartículas de dióxido de titânio (nano-TiO2) apresentam propriedades fotocatalíticas que devem ser consideradas na sua avaliação ecotoxicológica. Este trabalho teve por objetivo avaliar a toxicidade do nano-TiO2 em embriões de peixe, sob diferentes condições de iluminação. Embriões de paulistinha (Danio rerio) foram expostos a 0, 1, 10 e 100 mg/L de nano-TiO2 (anatase, 25 nm) sob luz visível ou luz visível e radiação ultravioleta (UV). O nano-TiO2 apresentou baixa toxicidade aguda em todas as condições testadas, porém após 96 h de exposição o grupo exposto a 100 mg/L com radiação UV apresentou 5% de mortalidade e redução no tamanho das larvas vivas. Observou-se eclosão prematura nos grupos expostos a 10 e 100 mg/L de nano-TiO2 sem UV. Estes resultados contribuem para compreensão dos efeitos ecotoxicológicos do nano- TiO2 e indicam que a condição de iluminação influencia tais efeitos
Combining Static and Dynamic Contract Checking for Curry
Static type systems are usually not sufficient to express all requirements on
function calls. Hence, contracts with pre- and postconditions can be used to
express more complex constraints on operations. Contracts can be checked at run
time to ensure that operations are only invoked with reasonable arguments and
return intended results. Although such dynamic contract checking provides more
reliable program execution, it requires execution time and could lead to
program crashes that might be detected with more advanced methods at compile
time. To improve this situation for declarative languages, we present an
approach to combine static and dynamic contract checking for the functional
logic language Curry. Based on a formal model of contract checking for
functional logic programming, we propose an automatic method to verify
contracts at compile time. If a contract is successfully verified, dynamic
checking of it can be omitted. This method decreases execution time without
degrading reliable program execution. In the best case, when all contracts are
statically verified, it provides trust in the software since crashes due to
contract violations cannot occur during program execution.Comment: Pre-proceedings paper presented at the 27th International Symposium
on Logic-Based Program Synthesis and Transformation (LOPSTR 2017), Namur,
Belgium, 10-12 October 2017 (arXiv:1708.07854
Bone mineral density in juvenile systemic lupus erythematosus
We evaluated spine bone mineral density (BMD) in Brazilian children with juvenile systemic lupus erythematosus (JSLE) in order to detect potential predictors of reduction in bone mass. A cross-sectional study of BMD at the lumbar spine level (L2-L4) was conducted on 16 female JSLE patients aged 6-17 years. Thirty-two age-matched healthy girls were used as control. BMD at the lumbar spine was measured by dual-energy X-ray absorptiometry. Weight, height and pubertal Tanner stage were determined in patients and controls. Disease duration, mean daily steroid doses, mean cumulative steroid doses and JSLE activity measured by the systemic lupus erythematosus disease activity index (SLEDAI) were determined for all JSLE patients based on their medical charts. All parameters were used as potential determinant factors for bone loss. Lumbar BMD tended to be lower in the JSLE patients, however, this difference was not statistically significant (P = 0.10). No significant correlation was observed in JSLE girls between BMD and age, height, Tanner stage, disease duration, corticosteroid use or disease activity. We found a weak correlation between BMD and weight (r = 0.672). In the JSLE group we found no significant parameters to correlate with reduced bone mass. Disease activity and mean cumulative steroid doses were not related to BMD values. We did not observe reduced bone mass in female JSLE.Universidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de PediatriaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Departamento de MedicinaUNIFESP, EPM, Depto. de PediatriaUNIFESP, EPM, Depto. de MedicinaSciEL
Disponibilidade do nitrogênio e sua absorção pelo milho em solo adubado com dejetos de suínos.
BRS Talento: cultivar semi-precoce de arroz de terras altas.
A preferência do consumidor brasileiro pelo arroz de classe longo fino, de aparência vítrea e translúcida após o beneficiamento, com menor tempo de cocçao e que, ao seu preparo, se apresenta com textura solta, macia e enxuta, vem se consolidando. Atendendo a esta preferência, o programa de melhoramento genético de arroz da Embrapa desenvolveu mais uma cultivar, a BRS Talento, para o cultivo em terras altas.bitstream/CNPAF/20436/1/comt_53.pd
Phenotypic plasticity of upland rice lines cultivated in Minas Gerais State, Brazil.
The evaluation of breeding lines for prior recommendation in different environments is a step that requires a high level of investment. This evaluation is extremely important, especially when the objective of breeding is to select lines with high homeostasis, adaptability associated with high yield, and stability. Thus, this paper aimed to study the phenotypic plasticity of thirteen upland rice lines for grain yield in multiple environments of Minas Gerais State, Brazil. The experiments were installed in nine different environments corresponding to the combination of locations and agricultural years. Thirteen elite lines were used, originating from a partnership between UFLA (Federal University of Lavras), Epamig (Agricultural Research Company of Minas Gerais) and Embrapa (Brazilian Company of Agricultural Research) Rice and Beans. The experiments were conducted in a complete randomized block design with three replicates. Culture treatments used for conducting were the same as those recommended for culture. The evaluated character was grain yield (kg.ha-1). Adaptability and stability were estimated by the methods Wricke, Annicchiarico, and Lin and Binns. All experiments showed average productivities above average in the state of Minas Gerais. The methods by Anniccchiarico and Lin Binns were efficient for the lines identification with phenotypic plasticity, emphasis on the lines CMG 2097, CMG 1896 and CMG 2089, which obtained superior average performance with productivities higher than 5 t.ha-1. Thus, these lines are promising for the Minas Gerais state recommendation, as well as in similar environments under low fertility natural soil, ferralsol (latosols), with tropical semi-humid and tropical altitude
Bit-Vector Model Counting using Statistical Estimation
Approximate model counting for bit-vector SMT formulas (generalizing \#SAT)
has many applications such as probabilistic inference and quantitative
information-flow security, but it is computationally difficult. Adding random
parity constraints (XOR streamlining) and then checking satisfiability is an
effective approximation technique, but it requires a prior hypothesis about the
model count to produce useful results. We propose an approach inspired by
statistical estimation to continually refine a probabilistic estimate of the
model count for a formula, so that each XOR-streamlined query yields as much
information as possible. We implement this approach, with an approximate
probability model, as a wrapper around an off-the-shelf SMT solver or SAT
solver. Experimental results show that the implementation is faster than the
most similar previous approaches which used simpler refinement strategies. The
technique also lets us model count formulas over floating-point constraints,
which we demonstrate with an application to a vulnerability in differential
privacy mechanisms
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