Dynamic of a tropical forest submitted to reduced impact logging in Belterra, Pará, Brazil.

The Amazon has a great biodiversity that needs research to ensure its development without the extinction of its natural resources. This study aims to increase understanding of changes in dynamics (recruitment, growth and mortality) of a natural forest under low impact forest logging over a period of six years

Dynamics of drinking water biofilm in flow/non-flow conditions

Drinking water biofilm formation on polyvinyl chloride (PVC), cross-linked polyethylene (PEX), high density polyethylene (HDPE) and polypropylene (PP) was followed in three different reactors operating under stagnant or continuous flow regimes. After one week, a quasi-steady state was achieved where biofilm total cell numbers per unit surface area were not affected by fluctuations in the concentration of suspended cells. Metabolically active cells in biofilms were around 17-35% of the total cells and 6-18% were able to form colony units in R(2)A medium. Microbiological analysis showed that the adhesion material and reactor design did not affect significantly the biofilm growth. However, operating under continuous flow (0.8-1.9 Pa) or stagnant water had a significant effect on biofilm formation: in stagnant waters, biofilm grew to a less extent. By applying mass balances and an asymptotic biofilm formation model to data from biofilms grown on PVC and HDPE surfaces under turbulent flow, specific growth rates of bacteria in the biofilm were found to be similar for both materials (around 0.15 day(-1)) and much lower than the specific growth rates of suspended bacteria (around 1.8 day(-1))

Prospecção fenotípica de genótipos de soja resistentes ao nematoide reniforme.

JIPE 2013

Averaging out magnetic forces with fast rf-sweeps in an optical trap for metastable chromium atoms

We introduce a novel type of time-averaged trap, in which the internal state of the atoms is rapidly modulated to modify magnetic trapping potentials. In our experiment, fast radiofrequency (rf) linear sweeps flip the spin of atoms at a fast rate, which averages out magnetic forces. We use this procedure to optimize the accumulation of metastable chomium atoms into an optical dipole trap from a magneto-optical trap. The potential experienced by the metastable atoms is identical to the bare optical dipole potential, so that this procedure allows for trapping all magnetic sublevels, hence increasing by up to 80 percent the final number of accumulated atoms.Comment: 4 pages, 4 figure

Genetic diversity as an additional selection criterion in a carioca common bean recurrent selection program for resistance to common bacterial blight.

Common beans are a key source of protein and are consumed daily by most of the Brazilian population. More than 70% of what is consumed in this country is classified as carioca beans, based on seed qualities and appearance. We evaluated progenies of carioca common beans of the Brazilian agriculture research agency (Embrapa) recurrent selection program. This recurrent selection program is based on resistance to common bean bacterial blight (CBB), seed yield, and other important agronomic traits. Selection also considers the genetic representativeness of the parents and the genetic diversity among phenotypically selected progenies. Initially, 60 superior progenies were selected based on resistance to CBB and on seed type, in two locations (Santo Antônio de Goiás, GO and Ponta Grossa, PR). These progenies were evaluated in the C0S0:2 generation in field trials in six locations during the rainy growing season. A randomized block experimental design was used with two replications, in plots of two 3-m rows spaced at 0.5 m. The most promising C0S0:3 progenies for combined agronomic performance in the different environments were selected and were then evaluated by means of 24 microsatellite molecular markers for the purpose of determining the genetic representativeness of their parents and the genetic diversity among them. The phenotypic data was subjected to analysis of variance for each trait in each of the environments, and then joint analyses were performed. To estimate genetic diversity among the progenies, the Rogers-W genetic distance was used, and a dissimilarity matrix was used to construct a dendrogram of genetic distances through the UPGMA method. Among the 60 C0S0:2 progenies that were evaluated, those that stood out for resistance to CBB also stood out for seed yield and for resistance to other diseases. Various progenies were superior, exhibiting large genetic distances between each other and in relation to the parents. This indicates a possibility of direct and indirect gains from the recurrent selection program. This molecular information will help direct selection of individuals for future recombination cycles

COVID-19 Management in Clinical Dental Care Part II: Personal Protective Equipment for the Dental Care Professional

Background: Facing the coronavirus disease 2019 (COVID-19) challenge on a global level, dental care professionals are encouraged to optimize universal precautions and adopt measures that ensure protection against infection by contaminated aerosols and droplets. Although aerosol transmission is possible, direct contact through large droplets is probably responsible for the vast majority of transmissions. Methods: This paper is the second of a series of 3 on the management of COVID-19 in clinical dental care settings and aims to describe the selection and use of personal protection equipment (PPE) by dental care professionals (DCP), with consideration of the level of risk associated with the planned procedures. PPE selection depends directly on the local epidemiological setting, the patient's characteristics, and the level of risk of the planned procedures. The procedures performed in the office environment are classified as low-, moderate-, or high-risk. Moderate risk includes 2 further sublevels associated with the cleaning, disinfection, and sterilization of materials for clinical procedures that do not generate aerosols. The training of DCP on how to properly don (put on) and doff (remove) PPE is as important as choosing the appropriate PPE because it can be associated with a risk of infection. Discussion: When there is limited availability of PPE, measures should be adjusted to the risk associated with the intervention. Assuming that an effective COVID-19 vaccine will be developed, once it becomes widely available for DCP, PPE requirements will likely be different. Conclusion: The proper use of PPE, together with the adoption of other operational procedures, can provide effective protection against microorganisms being transmitted via body fluids or in the air.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors