materials are typically developed at a critical length of under 100 nm. However, other phenomena, such as transparency and stable dispersion, can occasionally extend the upper limit, and the use of the prefix "nano" is accepted for dimensions smaller than 500 nm. [2] Two relevant factors differentiate nanomaterials from macroscopic materials: first, the quantum effect that can promote changes in physical properties, such as color and electrical conductivity, and second, the surface effect related to the increased surface area to volume ratio that favors physical and chemical interactions between atoms and the surrounding environment. [3] NPs are of the same order of magnitude as antibodies, membrane receptors, nucleic acids, proteins, and other biomolecules, thus representing a potential material to be used in medicine for imaging applications, diagnosis, therapies, or in medical devices. [4] The small size and large surface area of NPs facilitate their permeation through cell membranes and enhance their biological activity. [5] Microbial colonization of medical devices leads to the formation of microbial or fungal biofilms, which are complex assemblages of microbial cells associated with a surface and incorporated into an extracellular matrix. [6] Biofilms are critical clinical issues because they culminate in the pathogenesis of numerous bacterial infections that are difficult to treat and effectively eradicate with antibiotics. [7] Biofilm formation can occur in three stages: attachment, maturation, and dispersion. The attachment step can be further categorized in two-stage processes: initial reversible attachment and irreversible attachment, in which the attached biofilm can tolerate strong shear forces. [8] The bacteria deposition is mediated by sedimentation, Brownian motion, and hydrodynamic forces, whereas adhesion is governed by Van der Waals, acid-base, hydrophobic, and electrostatic interaction forces. [9] Attachment is the most crucial phase to prevent bacterial adhesion because the antimicrobial action becomes less effective after biofilm formation. [10] Medical devices commonly affected by microbial contamination and biofilm formation are catheters, probes, and wound dressings. Catheters are used in patients to administer fluids, blood products, and parenteral nutrition. [6] Most nosocomial infections in intensive care units (ICUs) are associated with the insertion and maintenance of central venous catheters Nanomaterials with antimicrobial activity are promising alternatives to overcome microbial resistance in medical devices. Catheters, probes, and wound dressings are among the medical devices mostly affected by microbial contamination and the formation of polymicrobial biofilms. Nanoparticles (NPs) derived from natural sources, such as chitosan nanoparticles (CsNPs), and metal-based nanoparticles, including silver nanoparticles (AgNPs), are receiving increased interest in nanomedicine. CsNPs have been widely explored as a coating material and antimicrobial agent. AgNPs have a strong antimicrobi...

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A cobertura vegetal e a verticalização presentes nas cidades são parâmetros relevantes para o planejamento urbano em relação à qualidade ambiental, pois envolvem a preocupação com o planejamento das cidades em suas diversas esferas. Uma das formas de agregar estas situações se refere ao Planejamento da Paisagem, que se constitui como um instrumento para a organização do espaço. A partir dos parâmetros cobertura vegetal e verticalização, objetivou-se realizar a classificação da cobertura do solo dos bairros Jardim Aeroporto, Jardim Araucária e Centro Comercial, localizados no município de Campo Mourão – Paraná. A classificação foi realizada por meio da construção de uma legenda a qual foi adaptada de Valaski (2013) e Nucci et al. (2014), com auxílio do software QGis 2.6, além de imagens de satélite. A partir da metodologia de Valaski (2013), foram realizadas inferências sobre a qualidade ambiental urbana, por meio da correlação com o parâmetro espaços construídos. Como resultado, observou-se que, nos três bairros estudados, há predominância da classe Espaços Edificados de até 4 pavimentos com vegetação inferior a 30%, o que contribui positivamente para a qualidade ambiental, se comparado a áreas onde há predominância de classes com espaços sem vegetação, impermeabilizados ou com mais de 4 pavimentos.Palavras-chave: Planejamento da Paisagem; cobertura vegetal; verticalização.

The availability of water is one of the most important factors for the development of the seeds. Thus, studies related to adequate humidity for germination, emergence and early development of safflowers, is necessary for the productive use of this culture. Thus, the objective of study was to evaluate the initial development of two varieties of seeds of Safflowers (IAPAR and IMA2103) in six levels of water availability in substrate: 0, 10, 20, 30, 40 and 50%. At 15 days the seedling emergence were evaluate. At 30 days were evaluate plant height, root length, stem diameter, number of leaves, fresh weight of the aerial part and root, dry weight of shoot and root. The treatment without irrigation, there was decrease the emergence, emergence speed for both genotypes. Treatments above 30% of water availability in the two varieties presented emergency superior to 50%. Lower irrigation rates favored root length and dry mass.

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This work aimed to apply ultraviolet radiation as an alternative treatment to inhibit microbial growth in diesel fuel. Samples of fuel were placed in a reactor equipped with ultraviolet C (UV-C) radiation lamps (40 W, 253 nm) and a fuel recirculation system. Assays were performed using different UV-C exposure times (0-360 min), volume (40 and 60 L), and with / without a circulation system. The microorganisms present in diesel were quantified using the drop-plate technique and spectrophotometric detection (600 nm), and were identified by genetic sequencing. Parameters such as color, specific mass, and kinematic viscosity were evaluated to verify whether UV radiation promotes changes in phyco-chemical fuel properties. The assay with 360 min of radiation exposure, with a circulation system, caused the microorganism concentration to decrease from 1.50 × 10 10 to 3.33 × 10 2 CFU mL −1 , but otherwise did not lead to any significant changes in fuel physicochemical properties. Microorganisms of the genera Staphylococcus sp., Enterococcus sp., Clostridium sp., Enterobacter sp. and Bacillus sp. were identified. It could be concluded that the use of UV radiation as a microbiological control method resulted in a reduction of around 99% in the concentration of the microorganisms.

Chitosan is a polycationic polysaccharide with good health and nutritional benefits. This study investigated the effect of chitosan properties, such as, biopolymer structure, viscometric molar mass (Mv), and degree of deacetylation (DD), on the fat‐binding capacity between five chitosan preparations (different origins and characteristics) and three types of fat (soybean oil, margarine, and pork lard). The in vitro fat‐binding tests were performed with soybean oil under different pH to simulate the digestion process in the gastrointestinal tract, followed by tests at constant pH (duodenal pH = 6.8) with three types of fat. Shrimp shell nanochitosan had an average hydrodynamic diameter of 62 nm, while that of shrimp shell chitosan and commercial chitosans (CC1, CC2, and CC3) ranged between 1090 and 1405 nm (determined by DLS). The Mv of chitosan varied between 18 and 260 kDa, and the DD ranged from 62% to 92%. Chitosan with medium Mv and high DD presented better results of fat‐binding capacity in the duodenal pH with soybean oil. This study provides insights into the mechanisms of fat‐binding capacity and its correlation with physicochemical properties of chitosan, pH, and type of fat, allowing the production of chitosan‐based products with improved fat‐binding capacity for several applications.