Temperature analysis during bonding of brackets using LED or halogen light base units

The purpose of our investigation is to compare the intrapulpal temperature changes following blue LED system and halogen lamp irradiation at the enamel surface of permanent teeth. The fixation of brackets using composite resin is more comfortable and faster when using a photo-curable composite. Several light sources can be used: halogens, arc plasma, lasers, and recently blue LED systems. An important aspect to be observed during such a procedures is the temperature change. In this study, we have used nine human extracted permanent teeth: three central incisors, three lateral incisors, and three canines. Teeth were exposed to two light sources: blue LED system (preliminary commercial model LEC 470-II) and halogen lamp (conventional photo-cure equipment). The surface of teeth was exposed for 20, 40, and 60 sec at the buccal and lingual enamel surface with an angle of 45 degrees. Temperature values measured by a thermistor placed at pulpar chamber were read in time intervals of 1 sec. We obtained plots showing the temperature evolution as a function of time for each experiment. There is a correlation between heating quantity and exposition time of light source: with increasing exposition time, heating increases into the pulpal chamber. The halogen lamp showed higher heating than the LED system, which showed a shorter time of cooling than halogen lamp. The blue LED system seems like the indicated light source for photo-cure of composite resin during the bonding of brackets. The fixation of brackets using composite resin is more comfortable and faster when using a photo-curable composite. Blue LED equipment did not heat during its use. This could permit a shorter clinical time of operation and better performance. © Mary Ann Liebert, Inc.

The frequency of pharmacological pain relief in university neonatal intensive care units

Objective: To evaluate the use of drugs to relieve the pain of invasive procedures newborn infants cared for at a university hospital NICU. Methods: A prospective cohort study of all newborn infants hospitalized in four NICU during October 2001. The following data were collected: demographic data of the hospitalized newborn infants; clinical morbidity; number of potentially painful procedures and frequency of analgesic administration. Factors associated with the use of analgesia in this cohort of patients were studied by multiple linear regression using SPSS 8.0. Results: Ninety-one newborn infants were admitted to the NICU during the study period (1,025 patient-days). Only 25% of the 1,025 patient-days received systemic analgesia. No specific drugs were administered to relieve acute pain during any of the following painful events: arterial punctures, venous, capillary and lumbar punctures or intubations. For chest tube insertion, 100% of newborn infants received specific analgesia. For the insertion of central catheters 8% of the newborn infants received painkillers. Only nine of the 17 newborn infants that underwent surgical procedures received any analgesic dosage during the postoperative period. For 93% of patients under analgesia the drug of choice was fentanyl. The presence of mechanical ventilation increased the chance of newborn infants receiving painkillers by 6.9 times and the presence of chest tube increased this chance by five times. Conclusion: It is necessary to train health professionals in order to bridge the gap between scientific knowledge regarding newborn infant pain and clinical practice. Copyright © 2005 by Sociedade Brasileira de Pediatria.

Biosynthetic origins of the isoprene units of 4-nerolidylcatechol in Potomorphe umbellata

The biosynthetic origins of the isoprene units of 4-nerolidylcatechol (1), the major constituent of Potomorphe umbellata, have been studied through feeding experiments with [14C]- and [13C]-glucose, and with precursors of the mevalonic acid and triose/pyruvate pathways, namely, [2- 14C]-mevalonolactone and [U-14C]-glyceraldehyde-3- phosphate, respectively. The pattern of incorporation of label from [1- 13C]-glucose into 1 was determined by quantitative 13C NMR spectroscopy. The labelling pattern revealed that the additive was specifically incorporated, and that the isoprene units of the sesquiterpenoid moiety of 4-nerolidylcatechol were derived from both the mevalonic acid and the triose/pyruvate pathways. The results indicate that both plastidic and cytoplasmic pathways are able to provide isopentenyl diphosphate units for the biosynthesis of 1. ©2005 Sociedade Brasileira de Química.

Evolutionary modeling of larval dispersal in blowflies using non-uniform cellular automata

When the food supply flnishes, or when the larvae of blowflies complete their development and migrate prior to the total removal of the larval substrate, they disperse to find adequate places for pupation, a process known as post-feeding larval dispersal. Based on experimental data of the Initial and final configuration of the dispersion, the reproduction of such spatio-temporal behavior is achieved here by means of the evolutionary search for cellular automata with a distinct transition rule associated with each cell, also known as a nonuniform cellular automata, and with two states per cell in the lattice. Two-dimensional regular lattices and multivalued states will be considered and a practical question is the necessity of discovering a proper set of transition rules. Given that the number of rules is related to the number of cells in the lattice, the search space is very large and an evolution strategy is then considered to optimize the parameters of the transition rules, with two transition rules per cell. As the parameters to be optimized admit a physical interpretation, the obtained computational model can be analyzed to raise some hypothetical explanation of the observed spatiotemporal behavior. © 2006 IEEE.

A preliminary investigation of pre-dispersal seed predation by Acanthoscelides schrankiae horn (Coleoptera: Bruchidae) in Mimosa bimucronata (DC.) Kuntze trees

This is the first record of Acanthoscelides schrankiae Horn, feeding in seeds of Mimosa bimucronata (DC.) Kuntze. We investigated the pattern of oviposition and seed exploitation by A. schrankiae, and the distribution of mature fruits and seed predation in the inflorescences. We also compared the percentage of predated seeds, the total dry weight of fruits and non-predated seeds, the percentage of aborted seeds, and the percentage of non-emergent insects, among different quadrants of the M. bimucronata canopy. To determine the occurring species, the emergence of bruchids and parasitoids was observed in the laboratory, resulting altogether, only in individuals of A. schrankiae and Horismenus sp. (Hymenoptera: Eulophidae) species, respectively. Mean number of fruits produced in the median region of inflorescence was significantly higher than in the inferior and superior regions, and the frequencies (observed and expected) of predated and non-predated seeds differed among the different regions of inflorescence. Females of A. schrankiae laid their eggs on fruits, and larvae, after emergence, perforated the exocarp to reach the seeds. Most fruits presented one to three eggs and only one bruchid larva was observed in each seed. The highest value of the rate number of eggs/fruit and the highest percentage of predated seeds were recorded in April. Dry weight of fruits (total) and seeds (non-predated), proportions of predated seeds, seed abortions, and non-emergent seed predators, were evenly distributed in the canopy.

The effect of different light-curing units on tensile strength and microhardness of a composite resin

The aim of this study was to evaluate the influence of different light-curing units on the tensile bond strength and microhardness of a composite resin (Filtek Z250 - 3M/ESPE). Conventional halogen (Curing Light 2500 - 3M/ESPE; CL) and two blue light emitting diode curing units (Ultraled - Dabi/Atlante; UL; Ultrablue IS - DMC; UB3 and UB6) were selected for this study. Different light intensities (670, 130, 300, and 600 mW/cm2, respectively) and different curing times (20s, 40s and 60s) were evaluated. Knoop microhardness test was performed in the area corresponding to the fractured region of the specimen. A total of 12 groups (n=10) were established and the specimens were prepared using a stainless steel mold composed by two similar parts that contained a cone-shaped hole with two diameters (8.0 mm and 5.0 mm) and thickness of 1.0 mm. Next, the specimens were loaded in tensile strength until fracture in a universal testing machine at a crosshead speed of 0.5 mm/min and a 50 kg load cell. For the microhardness test, the same matrix was used to fabricate the specimens (12 groups; n=5). Microhardness was determined on the surfaces that were not exposed to the light source, using a Shimadzu HMV-2 Microhardness Tester at a static load of 50 g for 30 seconds. Data were analyzed statistically by two-way ANOVA and Tukey's test (p<0.05). Regarding the individual performance of the light-curing units, there was similarity in tensile strength with 20-s and 40-s exposure times and higher tensile strength when a 60-s light-activation time was used. Regarding microhardness, the halogen lamp had higher results when compared to the LED units. For all light-curing units, the variation of light-exposure time did not affect composite microhardness. However, lower irradiances needed longer light-activation times to produce similar effect as that obtained with high-irradiance light-curing sources.

Dispersal of the delayed action insecticide sulfluramid in colonies of the leaf-cutting ant Atta sexdens rubropilosa (Hymenoptera: Formicidae)

Toxic baits are the most used control method for leaf-cutting ants due to their high effectiveness and because they are considered the safest for humans. Taking into account that the importance of leaf-cutting ants as pests, knowing the process by which dispersal and worker contamination is achieved becomes essential to understand several aspects about the functioning of a bait-borne AI (active ingredient) used in toxic baits. It has been established that an effective toxic bait should have a delayed- action AI, but its dispersion among the different sizes of workers is unknown. Workers of different sizes are involved in quite different tasks such foraging, cultivation of symbiotic macrofungus or control of deleterious microfungi. Therefore, we prepared a toxic bait containing the delayed-action AI sulfluramid and a dye (Rhodamine B) as an AI tracer in order to study dispersal and contamination in colonies, evaluated at different periods and in relation to different workers' sizes. Both field and laboratory colonies were evaluated. The great level of contamination, about 50% at 24 hours, in all sizes of workers demonstrates that worker contact with toxic bait is intense within this period. The distribution in field and laboratory colonies was similar. This contamination pattern is probably enough to cause the colony to die because of contamination of smaller workers, leading to the loss of control of the aggressive microfungi, which can quickly overgrow the symbiotic fungus culture. The dispersal dynamics of AI in leaf-cutting ant workers is important for investigations on the mode of action of this insecticide in the colony, and as a reference in future studies, such as those attempting to reduce the concentration of AIs in baits to reduce their environmental impact, or for facilitation of new AI screening.

Biosynthetic origin of the isoprene units in chromenes of Piper aduncum (Piperaceae)

Metabolic studies involving the incorporation of [1-13C]-D- glucose into intact leaves of Piper aduncum (Piperaceae) have indicated that both the mevalonate (MVA) and the pyruvate-triose (MEP) non-mevalonate pathways are implicated in the biosynthesis of isoprene moieties present in methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8- (3′-methyl-2′-butenyl)-2H-1-chromene-6-carboxylate (2). The pattern of incorporation of label from [1-13C]-D-glucose into these chromenes was determined by quantitative 13C NMR spectroscopy. The results confirmed that biosynthetic compartment of 1 and 2 could either be the plastid and/ or the cytosol or, possibly, an additional compartment such as the plastid inter-membrane space. ©2007 Sociedade Brasileira de Química.

Influence of pre-heat treatment and different light-curing units on Vickers hardness of a microhybrid composite resin

The aim of this study was to evaluate the hardness of a dental composite resin submitted to temperature changes before photo-activation with two light-curing unite (LCUs). Five samples (4 mm in diameter and 2 mm in thickness) for each group were made with pre-cure temperatures of 37, 54, and 60°C. The samples were photo-activated with a conventional quartz-tungsten-halogen (QTH) and blue LED LCUs during 40 s. The hardness Vickers test (VHN) was performed on the top and bottom surfaces of the samples. According to the interaction between light-curing unit and different pre-heating temperatures of composite resin, only the light-curing unit provided influences on the mean values of initial Vickers hardness. The light-curing unit based on blue LED showed hardness mean values more homogeneous between the top and bottom surfaces. The hardness mean values were not statistically significant difference for the pre-cure temperature used. According to these results, the pre-heating of the composite resin provide no influence on Vickers hardness mean values, however the blue LED showed a cure more homogeneous than QTH LCU. © 2009 Pleiades Publishing, Ltd.

Effect of light-curing units on push-out fiber post bond strength in root canal dentin

The purpose of this study was to evaluate the effectiveness of different light-curing units on the bond strength (push-out) of glass fiber posts in the different thirds of the root (cervical, middle and apical) with different adhesive luting resin systems (dual-cure total-etch; dual-cured and self-etch bonding system; and dual-cure self-adhesive cements), Disks of the samples (n = 144) were used, with approximately 1 mm of thickness of 48 bovine roots restored with glass fiber posts, that were luted with resin cements photo-activated by halogen LCU (QTH, Optilux 501) and blue LED (Ultraled), with power densities of 600 and 550 mW/cm 2, respectively. A universal testing machine (MTS 810 Material Test System) was used with a 1 mm diameter steel rod at cross-head speed of 0.5 mm/min until post extrusion, with load cell of 50 kg, for evaluation of the push-out strength in the different thirds of each sample. The push-out strength values in kgf were converted to MPa and analyzed through Analysis of Variance and Tukey's test, at significance level of 5%. The results showed that there were no statistical differences between the QTH and LED LCUs. The self-adhesive resin cement had lower values of retention. The total-etch and self-adhesive system resin cements seem to be a possible alternative for glass fiber posts cementation into the radicular canal and the LED LCU can be applied as an alternative to halogen light on photo-activation of dual-cured resin cements. © 2009 Pleiades Publishing, Ltd.

Fiscal decentralization: increasing social cohesion among widely disparate territorial units

Includes bibliography

Effect of pre-heating resin composite and light-curing units on monomer conversion

The purpose of this study was to evaluate the effect of pre-heating resin composite photo-cured with light-curing units (LCU) by FT-IR. Twenty specimens were made in a metallic mold (4 mm diameter × 2 mm thick) from composite resin-Tetric Ceram® (Ivoclar/Vivadent) at room temperature (25°C) and pre-heated to 37, 54, and 60°C. The specimens were cured with halogen curing light (QTH) and light emitted by diodes (LED) during 40 s. Then, the specimens were pulverized, pressed with KBr and analyzed with FT-IR. The data were submitted to statistical analysis of variance and Kruskal-Wallis test. Study data showed no statistically significant difference to the degree of conversion for the different light curing units (QTH and LED) (p > 0.05). With the increase of temperature there was significant increase in the degree of conversion (p < 0.05). In this study were not found evidence that the light curing unit and temperature influenced the degree of conversion. © 2010 Pleiades Publishing, Ltd.

Optimal phasor measurement units placement for fault location on overhead electric power distribution feeders

This paper proposes a new approach for optimal phasor measurement units placement for fault location on electric power distribution systems using Greedy Randomized Adaptive Search Procedure metaheuristic and Monte Carlo simulation. The optimized placement model herein proposed is a general methodology that can be used to place devices aiming to record the voltage sag magnitudes for any fault location algorithm that uses voltage information measured at a limited set of nodes along the feeder. An overhead, three-phase, three-wire, 13.8 kV, 134-node, real-life feeder model is used to evaluate the algorithm. Tests show that the results of the fault location methodology were improved thanks to the new optimized allocation of the meters pinpointed using this methodology. © 2011 IEEE.

Aquatic macroinvertebrates survey and assessment of two artificial reservoirs into conservation units from the Southeast Region of Brazil

This study aims to inventory and assess the aquatic macroinvertebrates fauna in two artificial reservoirs into conservation units with differences regarding conservation level and to anthropogenic impacts. The samplings were carried out in Caetetus Ecological Station and Bauru City Zoological Park, where some physical and chemical variables also were measured. The results obtained indicated that the Caetetus Ecological Station is more effective in the conservation of the diversity of aquatic macroinvertebrates compared to Bauru City Zoological Park. These results can be attributed to the strong anthropogenic impact suffered by the reservoir in Bauru and demonstrate the importance of these areas in maintaining the diversity of aquatic macroinvertebrates community.

Frugivory and Seed Dispersal by Northern Pigtailed Macaques (Macaca leonina), in Thailand

Tropical rain forest conservation requires a good understanding of plant-animal interactions. Seed dispersal provides a means for plant seeds to escape competition and density-dependent seed predators and pathogens and to colonize new habitats. This makes the role and effectiveness of frugivorous species in the seed dispersal process an important topic. Northern pigtailed macaques (Macaca leonina) may be effective seed dispersers because they have a diverse diet and process seeds in several ways (swallowing, spitting out, or dropping them). To investigate the seed dispersal effectiveness of a habituated group of pigtailed macaques in Khao Yai National Park, Thailand, we examined seed dispersal quantity (number of fruit species eaten, proportion in the diet, number of feces containing seeds, and number of seeds processed) and quality (processing methods used, seed viability and germination success, habitat type and distance from parent tree for the deposited seeds, and dispersal patterns) via focal and scan sampling, seed collection, and germination tests. We found thousands of seeds per feces, including seeds up to 58 mm in length and from 88 fruit species. Importantly, the macaques dispersed seeds from primary to secondary forests, via swallowing, spitting, and dropping. Of 21 species, the effect of swallowing and spitting was positive for two species (i. e., processed seeds had a higher % germination and % viability than control seeds), neutral for 13 species (no difference in % germination or viability), and negative (processed seeds had lower % germination and viability) for five species. For the final species, the effect was neutral for spat-out seeds but negative for swallowed seeds. We conclude that macaques are effective seed dispersers in both quantitative and qualitative terms and that they are of potential importance for tropical rain forest regeneration. © 2013 Springer Science+Business Media New York.