989 resultados para Free Software Movement
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Purpose: To evaluate the effects of Triesence (R) (TRI), a new preservative-free triamcinolone approved by the U. S. Food and Drug Administration (FDA) for intraocular use, on human retina pigment epithelial (ARPE-19) and rat neurosensory (R28) cells in culture. Methods: ARPE-19 and R28 cell cultures were treated 24 h with 1,000, 500, 200, or 100 mu g/mL of crystalline (cTRI) or 1,000, 500, or 200 mu g/mL of solubilized (sTRI). TRI was solubilized by centrifuging the drug, discarding the supernatant containing the vehicle and then resuspending the drug pellet in an equivalent amount of Dimethyl sulfoxide to achieve the same concentration as the commercial preparation. Percentage of cell viability (CV) was evaluated by a trypan blue dye-exclusion assay. The mitochondrial membrane potential (Delta Psi m) was analyzed with the JC-1 assay. The caspase-3/7 activity was measured by a fluorochrome assay. Results: In the ARPE-19 cultures, the cTRI caused a decrease in CV at 1,000 mg/mL (13.03 +/- 6.51; P < 0.001), 500 mu g/mL (28.87 +/- 9.3; P < 0.001), 200 mu g/mL (54.93 +/- 5.61; P < 0.001), and 100 mu g/mL (82.53 +/- 0.65; P < 0.005) compared with the untreated controls (96.98 +/- 0.16). In R28 cultures, the cTRI treatment also reduced CV values significantly (P < 0.001) for the 1,000 mu g/mL (22.73 +/- 2.44), 500 mu g/mL (34.63 +/- 1.91), 200 mu g/mL (58.70 +/- 1.39), and 100 mu g/m (75.33 +/- 2.47) compared with the untreated controls (86.08 +/- 3.54). Once the TRI was solubilized (sTRI), the CV and Delta Psi m remained similar to the untreated controls for both ARPE-19 and R28 cells. The sTRI treatment with 1,000, 500, and 200 mu g/mL increased in caspase-3/7 activity in ARPE-19 cells (P < 0.01) and in R28 cells (P < 0.05) compared with dimethyl sulfoxide equivalent controls. Conclusion: The crystalline form of TRI (cTRI) can cause a significant decrease in CV to cultured retinal cells. Once the TRI is solubilized (sTRI), at the same concentrations, the cells remain viable with no decrease in CV or Delta Psi m. The sTRI can, however, increase caspase-3/7 activity, thus suggesting some degree of apoptosis.
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Tick-borne bacteria were investigated in 10 free-living jaguars and their ticks in the Pantanal biome, Brazil. Jaguar sera were tested by indirect fluorescent antibody assays using Rickettsia rickettsii, Rickettsia parkeri, Rickettsia amblyommii, Rickettsia rhipicephali, Rickettsia felis, Rickettsia bellii, Ehrlichia canis, and Coxiella burnetii as crude antigens. All 10 jaguar sera reacted (titer >= 64) to at least one Rickettsia species; 4 and 3 sera reacted with E. canis and C. burnetii, respectively. One jaguar presented antibody titer to R. parkeri at least fourfold higher than those to any of the other five Rickettsia antigens, suggesting that this animal was infected by R. parkeri. Ticks collected from jaguars included the species Amblyomma cajennense, Amblyomma triste, and Rhipicephalus (Boophilus) microplus. No Rickettsia DNA was detected in jaguar blood samples, but an A. triste specimen collected on a jaguar was shown by PCR to be infected by R. parkeri. The blood of two jaguars and samples of A. triste, A. cajennense, and Amblyomma sp. yielded Ehrlichia DNA by PCR targeting the ehrlichial genes 16S rRNA and dsb. Partial DNA sequences obtained from PCR products resulted in a new ehrlichial strain, here designated as Ehrlichia sp. strain Jaguar. A partial DNA sequence of the 16S rRNA gene of this novel strain showed to be closest (99.0%) to uncultured strains of Ehrlichia sp. from Japan and Russia and 98.7% identical to different strains of Ehrlichia ruminantium. The ehrlichial dsb partial sequence of strain jaguar showed to be at most 80.7% identical to any Ehrlichia species or genotype available in GenBank. Through phylogenetic analysis, Ehrlichia sp. strain jaguar grouped in a cluster, albeit distantly, with different genotypes of E. ruminantium. Results highlight risks for human and animal health, considering that cattle ranching and ecotourism are major economic activities in the Pantanal region of Brazil.
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The prevalence of Toxoplasma gondii in free-ranging chickens is a good indicator of the prevalence of 7: gondii oocysts in the soil because chickens feed from the ground. The prevalence of T. gonulii in 152 free-range chickens (Gallus domesticus) from 22 municipalities in 7 northeastern states (Pernambuco, Rio Grande do Norte, Maranh5o, Bahia, Ceara, Sergipe, and Alagoas) of Brazil was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT); 81 (53.3 %) chickens had titers of 1:5 in 26, 1:10 in 9, 1:20 in 4, 1:40 in 1, 1:80 in 6, 1:160 in 6, 1:320 in 13, 1:640 in 6, 1:1,280 in 3, 1:2,560 in 6, and 1:5,120 or higher in I. Hearts and brains of 81 seropositive chickens were bioassayed individually in mice. Toxoplasma gondii was isolated from 23 chickens with MAT titers of 1:5 or higher; the isolates were designated TgCKBr165-187. Five isolates killed all infected mice. Results indicate widespread contamination of rural environment in Brazil with T. gondii oocysts.
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Objectives: This study evaluates the action of a low-intensity diode laser with gallium-aluminum-arsenide (GaAlAs) active medium on the healing process and analgesia in individuals undergoing free gingival grafts. Material and Method: Ten individuals needing bilateral gingival graft in the mandibular arch were enrolled in a double-blind study. Each individual had a 30-d interval between the two surgeries. The side receiving application of laser was defined as test side and was established upon surgery; laser application was simulated on the control side. The laser was applied in the immediate postoperative period and after 48 h, and patients rated pain on a scale of 0 to 10, representing minimal and maximal pain, respectively. Photographs were obtained at 7, 15, 30, and 60d postoperatively and evaluated by five periodontists. Results: No statistically significant difference was found at any postoperative period between control and test sides, even though greater clinical improvement associated with treatment was observed at 15d postoperative. At 30 and 60d, some examiners observed the same or greater clinical improvement for the control. Only one individual reported mild to moderate pain on the first postoperative day. Conclusions: Low-intensity laser therapy did not improve the healing of gingival grafts and did not influence analgesia.
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Objective: To determine if the magnitude of the force used to induce incisor tooth movement promotes distinct activation in cells in the central amygdala (CEA) and lateral hypothalamus (LH) of rats. Also, the effect of morphine on Fos immunoreactivity (Fos-IR) was investigated in these nuclei. Materials and Methods: Adult male rats were anesthetized and divided into six groups: only anesthetized (control), without orthodontic appliance (OA), OA but without force, OA activated with 30g or 70g, OA with 70g in animals pretreated with morphine (2 mg/kg, intraperitoneal). Three hours after the onset of the experiment the rats were reanesthetized and perfused with 4% paraformaldehyde. The brains were removed and fixed, and sections containing CEA and LH were processed for Fos protein immunohistochemistry. Results: The results show that in the control group, the intramuscular injection of a ketamine/xylazine mixture did not induce Fos-IR cells in the CEA or in the LH. Again, the without force group showed a little Fos-IR. However, in the 70g group the Fos-IR was the biggest observed (P < .05, Tukey) in the CEA and LH compared with the other groups. In the 30g group, the Fos-IR did not differ from the control group, the without OA group, and the without force group. Furthermore, pretreatment with morphine in the 70g group reduced Fos-IR in these regions. Conclusions: Tooth movement promotes Fos-IR in the CEA and LH according to the magnitude of the force applied. (Angle Orthod. 2010;80:111-115.)
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This paper presents SMarty, a variability management approach for UML-based software product lines (PL). SMarty is supported by a UML profile, the SMartyProfile, and a process for managing variabilities, the SMartyProcess. SMartyProfile aims at representing variabilities, variation points, and variants in UML models by applying a set of stereotypes. SMartyProcess consists of a set of activities that is systematically executed to trace, identify, and control variabilities in a PL based on SMarty. It also identifies variability implementation mechanisms and analyzes specific product configurations. In addition, a more comprehensive application of SMarty is presented using SEI's Arcade Game Maker PL. An evaluation of SMarty and related work are discussed.
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We report on an experimental study of the structures presented by urethane/urea elastomeric films without and with ferromagnetic nanoparticles incorporated. The study is made by using the X-ray diffraction, nuclear magnetic resonance (NMR), optical, atomic and magnetic force (MFM) microscopy techniques, and mechanical assays. The structure of the elastomeric matrix is characterized by a distance of 0.46 nm between neighboring molecular segments, almost independent on the stretching applied. The shear casting performed in order to obtain the elastomeric films tends to orient the molecules parallel to the flow direction thus introducing anisotropy in the molecular network which is reflected on the values obtained for the orientational order parameter and its increase for the stretched films. In the case of nanoparticles-doped samples, the structure remains nearly unchanged although the local order parameter is clearly larger for the undoped films. NMR experiments evidence modifications in the molecular network local ordering. Micrometer size clusters were observed by MFM for even small concentration of magnetic particles.
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We derive a closed form expression for the sum of all the infrared divergent contributions to the free energy of a gas of gravitons. An important ingredient of our calculation is the use of a gauge fixing procedure such that the graviton propagator becomes both traceless and transverse. This has been shown to be possible, in a previous work, using a general gauge fixing procedure, in the context of the lowest order expansion of the Einstein-Hilbert action, describing noninteracting spin-two fields. In order to encompass the problems involving thermal loops, such as the resummation of the free energy, in the present work, we have extended this procedure to the situations when the interactions are taken into account.
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In this paper we study the one-and two-loop contribution to the free energy in QED with Lorentz symmetry breaking introduced via constant CPT-even Lorentz-breaking parameters at the high temperature limit. We find the impact of the Lorentz-violating term for the free energy and carry out a numerical estimation for the Lorentz-breaking parameter.
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Using ab initio methods, we propose a simple and effective way to substitutionally dope graphene sheets with boron. The method consists of selectively exposing each side of the graphene sheet to different elements. We first expose one side of the membrane to boron while the other side is exposed to nitrogen. Proceeding this way, the B atoms will be spontaneously incorporated into the graphene membrane without any activation barrier. In a second step, the system should be exposed to a H-rich environment, which will remove the CN radical from the layer and form HCN, leading to a perfect substitutional doping.
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In this paper we detail some results advanced in a recent letter [Prado et al., Phys. Rev. Lett. 102, 073008 (2009).] showing how to engineer reservoirs for two-level systems at absolute zero by means of a time-dependent master equation leading to a nonstationary superposition equilibrium state. We also present a general recipe showing how to build nonadiabatic coherent evolutions of a fermionic system interacting with a bosonic mode and investigate the influence of thermal reservoirs at finite temperature on the fidelity of the protected superposition state. Our analytical results are supported by numerical analysis of the full Hamiltonian model.
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We study the free-fall of a quantum particle in the context of noncommutative quantum mechanics (NCQM). Assuming noncommutativity of the canonical type between the coordinates of a two-dimensional configuration space, we consider a neutral particle trapped in a gravitational well and exactly solve the energy eigenvalue problem. By resorting to experimental data from the GRANIT experiment, in which the first energy levels of freely falling quantum ultracold neutrons were determined, we impose an upper-bound on the noncommutativity parameter. We also investigate the time of flight of a quantum particle moving in a uniform gravitational field in NCQM. This is related to the weak equivalence principle. As we consider stationary, energy eigenstates, i.e., delocalized states, the time of flight must be measured by a quantum clock, suitably coupled to the particle. By considering the clock as a small perturbation, we solve the (stationary) scattering problem associated and show that the time of flight is equal to the classical result, when the measurement is made far from the turning point. This result is interpreted as an extension of the equivalence principle to the realm of NCQM. (C) 2010 American Institute of Physics. [doi:10.1063/1.3466812]
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Background: The inference of gene regulatory networks (GRNs) from large-scale expression profiles is one of the most challenging problems of Systems Biology nowadays. Many techniques and models have been proposed for this task. However, it is not generally possible to recover the original topology with great accuracy, mainly due to the short time series data in face of the high complexity of the networks and the intrinsic noise of the expression measurements. In order to improve the accuracy of GRNs inference methods based on entropy (mutual information), a new criterion function is here proposed. Results: In this paper we introduce the use of generalized entropy proposed by Tsallis, for the inference of GRNs from time series expression profiles. The inference process is based on a feature selection approach and the conditional entropy is applied as criterion function. In order to assess the proposed methodology, the algorithm is applied to recover the network topology from temporal expressions generated by an artificial gene network (AGN) model as well as from the DREAM challenge. The adopted AGN is based on theoretical models of complex networks and its gene transference function is obtained from random drawing on the set of possible Boolean functions, thus creating its dynamics. On the other hand, DREAM time series data presents variation of network size and its topologies are based on real networks. The dynamics are generated by continuous differential equations with noise and perturbation. By adopting both data sources, it is possible to estimate the average quality of the inference with respect to different network topologies, transfer functions and network sizes. Conclusions: A remarkable improvement of accuracy was observed in the experimental results by reducing the number of false connections in the inferred topology by the non-Shannon entropy. The obtained best free parameter of the Tsallis entropy was on average in the range 2.5 <= q <= 3.5 (hence, subextensive entropy), which opens new perspectives for GRNs inference methods based on information theory and for investigation of the nonextensivity of such networks. The inference algorithm and criterion function proposed here were implemented and included in the DimReduction software, which is freely available at http://sourceforge.net/projects/dimreduction and http://code.google.com/p/dimreduction/.
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We used morphological and molecular approaches to evaluate the diversity of free-living marine nematodes (order Enoplida) at four coastal sites in the Gulf of California and three on the Pacific coast of Baja California, Mexico. We identified 22 morphological species belonging to six families, of which Thoracostomopsidae and Oncholaimidae were the most diverse. The genus Mesacanthion (Thoracostomopsidae) was the most widespread and diverse. Five allopatric species, genetically and morphologically differentiated, were found in two localities in the Gulf of California (M. sp1 and M. sp2) and three in the Pacific coast (M. sp3, M. sp4 and M. sp5). Overall, we produced 19 and 20 sequences for the 18S and 28S genes, respectively. Neither gene displayed intraspecific polymorphisms, which allowed us to establish that some morphological variation was likely either ontogenetic or due to phenotypic plasticity. Although 18S and 28S phylogenies were topologically congruent (incongruence length difference test, P > 0.05), divergences between species were much higher in the 28S gene. Moreover, this gene possessed a stronger phylogenetic signal to resolve relationships involving Rhabdodemania and Bathylaimus. On the other hand, the close relationship of Pareurystomina (Enchilidiidae) with oncholaimids warrants further study. The 28S sequences (D2D3 domain) may be better suited for DNA barcoding of marine nematodes than those from the 18S rDNA, particularly for differentiating closely related or cryptic species. Finally, our results underline the relevance of adopting an integrative approach encompassing morphological and molecular analyses to improve the assessment of marine nematode diversity and advance their taxonomy.
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A flow system designed with solenoid micro-pumps is proposed for fast and greener spectrophotometric determination of free glycerol in biodiesel. Glycerol was extracted from samples without using organic solvents. The determination involves glycerol oxidation by periodate, yielding formaldehyde followed by formation of the colored (3,5-diacetil-1,4-dihidrolutidine) product upon reaction with acetylacetone. The coefficient of variation, sampling rate and detection limit were estimated as 1.5% (20.0 mg L(-1) glycerol, n =10), 34 h(-1), and 1.0 mg L(-1) (99.7% confidence level), respectively. A linear response was observed from 5 to 50 mg L(-1), with reagent consumption estimated as 345 mu g of KIO(4) and 15 mg of acetylacetone per determination. The procedure was successfully applied to the analysis of biodiesel samples and the results agreed with the batch reference method at the 95% confidence level. (C) 2010 Elsevier B.V. All rights reserved.