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Several theoretical frameworks have been used to understand exercise adherence. Basic psychological needs (BPN), grounded on self‐determination theory, have received large attention for this purpose. More recently, the hedonic theory and the assumptions related to the exercise characteristics (e.g., intensity) that can bolster positive affective responses have been revitalized. This study aimed to explore the associations between the agreement of current exercise intensity and the one individually preferred, BPN satisfaction/frustration, enjoyment, the intention to continue exercise, and exercise frequency. Additionally, an exploration of the direct and indirect effects while testing sex as a moderator was performed. A sample of 369 exercisers (Mage = 43.6, standard deviation = 12.96; 214 females) enrolled in 26 health clubs participated in this study voluntarily. Data were received in a first‐approach descriptive and correlational analyses. Next, a moderated mediation was performed using model 15 (PROCESS v.4.2). As a result, agreement in preference for exercise intensity was positively associated with enjoyment (r = 0.35), intention (r = 0.43), and all needs satisfaction (ranging from r = 0.12 to r = 0.45) and negatively associated with all needs frustration (ranging from r = −0.15 to r = −0.31). In the moderated mediation analysis, the same pattern of results emerged in direct effects. Indirect effects were significant for autonomy in the enjoyment and frequency models. Findings suggest that promoting an individually adjusted training intensity may foster BPN satisfaction. It appears to be present an independent (of needs) and positive association with exercise enjoyment and intention to continue exercising. Highlights: An agreement between exercise intensity and the one individually preferred can be seen as a need‐supportive toolExercise intensity agreement presents an independent effect on exercise enjoyment and intentionThe way autonomy promotes enjoyment may be different between sexes, a relation that seems to favor menFemales appear to be more dependent on preference agreement to support enjoyment and intention, while in men, this relation appears to be valid only for intention [ABSTRACT FROM AUTHOR]

Citrate-coated silver nanoparticles (citrate-AgNPs) are among the most commonly used nanomaterials, widely present in industrial and biomedical products. In this study, the cytotoxicity of 30-nm citrate-AgNPs on the macrophage cell line RAW 264.7 was evaluated, using a battery of cytotoxicity endpoints (viability, oxidative stress, and cytostaticity/clastogenicity), at 24 and 48 h of exposure. Citrate-AgNPs decreased cell proliferation and viability only at 75 μg/mL, suggesting a low sensitivity of RAW cells to lower doses of these AgNPs. After 24 h of exposure, ROS content decreased in cells exposed to 60 μg/mL AgNPs (IC20 value), corroborating the high tolerance of these cells to citrate-AgNPs. However, these cells suffered an impairment of the cell cycle, shown by an increase at the sub-G1 phase. This increase of the sub-G1 population was correlated with an increase of DNA fragmentation, suggesting an increase of apoptosis. Thus, our data are important to understand the effects of low concentrations (IC20) of citrate-AgNPs on in vitro vital macrophage functions. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are widely used in industrial, cosmetic, and biomedical products, and humans are frequently exposed to these products through the skin. It is widely recognized that the characteristics of AgNPs (e.g., size, coating) may influence their cytotoxic effects, but their correlation with DNA damage and mitotic disorders remains poorly explored. In this study, human keratinocytes (HaCaT cell line) were exposed to well-characterized 30 nm AgNPs coated with citrate, and their effects on viability, DNA fragmentation (assessed by the comet assay), and micronuclei (MNi) induction (assessed by the cytokinesis-block micronucleus cytome assays, CBMN) were investigated. The results showed that 10 and 40 μg/mL AgNPs decreased cell proliferation and viability, and induced a significant genetic damage. This was observed by an increase of DNA amount in comet tail, which linearly correlated with dose and time of exposure. Also, cytostaticity (increase of mononucleated cells) and MNi rates increased in treated cells. In contrast, no significant changes were observed in nucleoplasmatic bridges (NPBs) or nuclear buds (NBUDs), although NBUDs tended to increase in all conditions and periods. The cytostatic effects on HaCaT cells were also shown by the decrease of their nuclear division index. Thus, both comet and CBMN assays supported the observation that citrate-AgNPs induced genotoxic effects on HaCaT cells. Considering that AgNPs are present in a vast number of consumer products and also in multiple nanomedicine skin applications and formulations, more research is needed to determine the properties that confer less toxicity of AgNPs to different cell lines. [ABSTRACT FROM AUTHOR]

Advances in geotechnologies and in remote sensing have improved analysis of urban environments. The new sensors are increasingly suited to urban studies, due to the enhancement in spatial, spectral and radiometric resolutions. Urban environments present high heterogeneity, which cannot be tackled using pixel-based approaches on high resolution images. Geographic Object-Based Image Analysis (GEOBIA) has been consolidated as a methodology for urban land use and cover monitoring; however, classification of high resolution images is still troublesome. This study aims to assess the improvement on ceramic roof classification using WorldView-2 images due to the increase of 4 new bands besides the standard "Blue-Green-Red-Near Infrared" bands. Our methodology combines GEOBIA, C4.5 classification tree algorithm, Monte Carlo simulation and statistical tests for classification accuracy. Two samples groups were considered: 1) eight multispectral and panchromatic bands, and 2) four multispectral and panchromatic bands, representing previous high-resolution sensors. The C4.5 algorithm generates a decision tree that can be used for classification; smaller decision trees are closer to the semantic networks produced by experts on GEOBIA, while bigger trees, are not straightforward to implement manually, but are more accurate. The choice for a big or small tree relies on the user's skills to implement it. This study aims to determine for what kind of user the addition of the 4 new bands might be beneficial: 1) the common user (smaller trees) or 2) a more skilled user with coding and/or data mining abilities (bigger trees). In overall the classification was improved by the addition of the four new bands for both types of users. [ABSTRACT FROM AUTHOR]

In cytosol from liver of pacu, Piaractus mesopotamicus, a hypoxia-tolerant fish that dwells in Pantanal, we found an enzyme activity capable of modulating the alkenal 4-hydroxy-2-nonenal (HNE) by conjugating it with glutathione (GST-HNE activity). HNE is a downstream metabolite from the oxidation of polyunsaturated fatty acids by reactive oxygen species arisen from mitochondria of animal cells. HNE production may increase more intensively under oxidative stress. Harmful effects to cell survival may occur when HNE increases over 10 M. Pacus submitted to hypoxia in July (cold season in Pantanal) showed 40 % less of this GST-HNE conjugating activity in their liver cytosol. Injecting pacus subjected to hypoxia during the cold season with a summer physiological dose of melatonin caused their liver cytosolic GST-HNE activity to increase up to the levels found in the warm season. From October to March (warm season in Pantanal), pacus are prone to oxidative stress particularly during potamodromous active oxygen-demanding swimming, when they migrate up rivers to spawn. Thus, our findings point out that the higher levels of melatonin in circulation during the summer are important to avoid the increase of 4-HNE inside liver cells of this fish species. [ABSTRACT FROM AUTHOR]

In the present study, a practical activity is proposed to adopt an experimental approach to demonstrate the relationship between the equilibrium potential for K+ and transmembrane electrical potential without glass micropipettes. A conventional setup for recording contractile activity of isolated smooth muscle preparations was used based on the events elegantly described by Somlyo and Somlyo in the 1960s. They showed that, in response to a given stimulus, smooth muscle cells may contract, recruiting electromechanical or pharmacomechanical coupling by mechanisms that involve, or not, changes in transmembrane potential, respectively. By means of contractions and relaxations of a ring-like preparation from the rat mesenteric artery, it is possible to observe the functional consequences of handling K+ concentration in the extracellular compartment and the effects caused by opening K+ channels in that preparation, which are significant when the cell membrane establishes an electrical potential difference between intra- and extracellular compartments (driven mainly by K+ permeability under resting conditions). The effects observed by students fit well with values predicted by Nernst and Goldman-Hodgin-Katz equations, and we demonstrated that the activity is able to improve students' comprehension regarding basic principles of bioelectricity. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are characterized by their small size (less than 100 nm) and large surface area, which confer specific physicochemical properties as strength, electrical, and optical features. NPs can be derived from natural or anthropic sources, such as engineered or unwanted/incidental NPs. The composition, dimension, and morphology of engineered NPs enable their use in a variety of areas, such as electronic, biomedical, pharmaceutical, cosmetic, energy, environmental, catalysis, and materials science. As nanotechnology is an innovative and scientific growth area with an exponential production, more information is needed concerning the impacts of these nanomaterials (NMs) in the environment and, particularly, in animals/humans health and in plants performance. So, research on NPs as emerging contaminants is therefore a new field in environmental health. This minireview describes, briefly, the NPs characterization and their occurrence in the environment stating air, water, and soil. Finally, particular emphasis is given to the interaction of NPs with plants at different levels: morphology, physiology, and genotoxicity. By analyzing this compiled information, it is evident that research on NPs phytotoxicity is in the beginning, and more comprehensive studies are needed not only on NPs cytotoxicity and genotoxicity but also on the best and the most reliable methods of assessing NPs toxicity. [ABSTRACT FROM AUTHOR]

The values of Michaelis–Menten constant (KM) and maximum velocity (VMAX) for kidney and heart monoamine oxidase (MAO) from pacu Piaractus mesopotamicus were determined. The mean ±s.e. KM values were 17·28 ± 2·27 μM for kidney and 15·38 ± 1·86 μM for heart. MAO activities were 111·60 ± 3·25 and 15·12 ± 0·30 nmols min−1 g−1 of wet tissue for kidney and heart, respectively. In addition, MAO inhibitory studies in these two tissues indicate that this enzyme may be a different isoform of MAO. [ABSTRACT FROM AUTHOR]

In this paper, we describe that the oxoquinolinic acid derivative (compound A) inhibited HSV-1 adsorption on Vero cells. This effect was achieved with an EC50 value of 10 ± 2.0 µM and with low cytotoxicity, since the CC50 value for compound A was >1000 µM. Moreover, we demonstrate for the first time that adsorption inhibition was due to the blockage of the interactions between HSV-1 and the cellular receptor herpes virus entry mediator (HVEM). These results show that compound A can prevent HSV-1 infection in Vero cells, encouraging further studies to determine at what level compound A inhibits HSV-1-HVEM interactions. [ABSTRACT FROM AUTHOR]

This article focuses on paraoxonase activity in neotropical fish. In Brazil, parathion, O,O-diethyl O-p-nitrophenyl phosphorothioate is still in use in many insecticide preparations, not only to protect crops, but also in aquaculture to avoid larvae of predatory insects and some parasites that attack juvenile fish. It has been demonstrated that fish can metabolize through oxidative desulphurization the non-toxic parathion into paraoxon, O,O-diethyl O-p-nitrophenyl phosphate, the anticholinesterase oxon ester.

The article describes the presence of cytochromes P450 in liver microsomes from pacu and its major specific deethylase activity, which was inducible by β-napthoflavone. Pacus of both sexes weighing around 400 gram were donated by the National Centre for Research on Tropical Fish of the Brazilian Environment and Renewable Natural Resources Institute. They were acclimated for three weeks in 500 liter tanks equipped with biologic filter and filled with aerated dechlorinated freshwater at 24 &degree;Celsius.

Inclusive differential cross sections dσpA/dxF and dσpA/dpt² for the production of KS0, Λ, and Λ particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to √s = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dσpA(KS0)/dσpA(Λ) and dσpA(Λ)/dσpA(Λ) are measured to be 6.2 ± 0.5 and 0.66 ± 0.07, respectively, for xF ≈ -0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions dσpA/dpt² also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections σpA on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon σpN are compared with results obtained at other energies. [ABSTRACT FROM AUTHOR]

RID=""ID="" Correspondence to: J. Cunha Bastos http://link.springer.de/link/service/journals/00128/bibs/0064002/00640191.htm [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the sensitivity of serum and brain cholinesterase of Pacu, an indigenous Brazilian fish, to paraoxon. Paraoxon is a potent anticholinesterase organophosphate pesticide. Inhibition of brain acetylcholinesterase (AChE) activity is known to cause the toxicity of organophosphorus compounds to vertebrates and some non-Brazilian fish species. The study used blood samples from Pacu specimens which were donated by the Research and Training Centre for Aquaculture. Results of the study indicated that determining the level of sensitivity can be more established if Pacu specimens are intoxicated rather than assaying only their brain AChE.