Abstract This study determined the effect of thiourethane-functionalized fillers (TU) on the antimicrobial properties, cytotoxicity, degree of conversion (DC), water sorption (Wsp) and solubility (Wsl) of experimental composites. TU-modified fillers were added at different ratios in experimental composites: 0 (Control-TU0), 25% (TU25), 50% (TU50), 75% (TU75) and 100wt% (TU100). The antimicrobial properties were detected through the exhaustion test and counting of Streptococus mutans colonies for biofilm formation. Cytotoxicity to human gingival fibroblasts was evaluated in three different parameters: XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide), NRU (Neutral Red Uptake assay) and CVDE (Crystal Violet Dye Exclusion test)) at the same cells. ELISA was used to measure the IL-6 and b-FGF biomarkers. DC was determined by Fourier-transformed infrared spectroscopy, while Wsp and Wsl by mass variations. Inhibitory capacity of biofilm formation was not observed for any material. All groups presented at least 70% of cell survival within the observed periods (24h and 7 days). Positive control (toxic) had high IL-6 values and low b-FGF values. No significant variations in DC, Wsp, and Wsl were observed among the experimental groups. The use of thiourethane did not present antimicrobial and cytotoxic activity and the tested materials presented equivalent properties to those conventionally used in dentistry.

Resumo Introdução A camada superficial de resina composta não polimerizada, em função da presença do oxigênio, ocasiona problemas clínicos, como alteração de cor por absorção de pigmentos. Objetivo Determinar o efeito de diferentes técnicas usadas no controle da formação da camada de dispersão sobre as propriedades ópticas de uma resina composta comercial. Material e método Espécimes foram produzidos com a resina composta Estelite Sigma. A fotoativação foi conduzida com uma fonte de luz LED Bluephase G2 (1.200 mW/cm2 por 40 s). Os grupos foram determinados em função de três técnicas distintas: 1) sem tratamento (controle); 2) fotoativação com gel de glicerina; 3) polimento com lixa abrasiva após a fotoativação. A estabilidade de cor (ΔE) e o parâmetro de translucidez foram determinados pelo método de espectroscopia de reflectância (Easyshade Compac, Vita) empregando o parâmetro CIELab. As análises foram realizadas imediatamente após a fotoativação e repetidas após 7 dias de armazenamento em água ou em café. Os resultados foram submetidos à análise de variância e ao teste de Tukey (α = 0,05). Resultado Não houve diferença para ΔE nos grupos envelhecidos em água. Quando armazenados em café, o grupo controle apresentou o maior valor de ΔE, enquanto o grupo polido gerou a menor alteração de cor. A aplicação do gel de glicerina produziu resultados intermediários. O parâmetro de translucidez não foi afetado pelos tratamentos testados. Conclusão O uso do gel de glicerina minimiza a alteração de cor nas regiões de difícil acesso aos instrumentos de acabamento e de polimento.

Abstract Introduction The resin composite superficial layer not polymerized due to the presence of oxygen leads to clinical problems as color alteration by the absorption of pigments. Objective Evaluate the effect of different techniques to control the formation of the composite resin dispersion layer on the optical properties of a commercial composite. Material and method Resin composite Estelite Sigma specimens were made. The specimens were light-cured with the LED Bluephase G2 device (1200 mW/cm2 - 40 s). The groups were determined according to three different techniques: 1) no treatment (control); 2) light-curing through a glycerin gel layer on the surface; 3) polishing with abrasive discs after light-curing. The color stability (ΔE) and the translucency parameter were determined by the spectroscopy method (Easyshade Compact Vita) as a function of the CIELab parameter. The analyzes were performed immediately after photoactivation and repeated after 7 days of storage in water or 7 days in coffee. The results were submitted to ANOVA and Tukey test (α = 0.05). Result No difference was found for ΔE in groups aged in water. When stored in coffee, the control group had the highest value of ΔE while the polished group generated the lowest color change. The glycerin gel groups promoted intermediated results. The translucency parameter was not affected by the treatments tested. Conclusion: The glycerin-based gel layer minimizes the color change in those regions that the finishing and polishing instruments are difficult to access.

RESUMO: Objetivou-se avaliar o desempenho e consumo de matéria seca de bezerras manejadas em pastoreio rotativo, com intervalos de pastoreio definidos por duas somas térmicas relacionadas à duração de elongação foliar de dois grupos funcionais de gramíneas durante a estação fria em pastagem natural. O delineamento experimental foi o de blocos completamente casualizados, com dois tratamentos e três repetições de área na região central do Rio Grande do Sul, Brasil. Os tratamentos foram duas somas térmicas: 375 e 750 graus-dias (GD), que determinaram os intervalos entre os pastoreios. Foram utilizadas trinta e seis bezerras de corte com idade média de 18 meses e peso corporal médio de 220±14kg. Durante todo o experimento, as bezerras receberam como suplemento grão de milho moído a uma taxa de 0,5% do peso corporal por dia, às 14:00 horas e tiveram livre acesso à suplementação proteínada (45% PB). Não houve diferença para o ganho médio diário, ganho de peso por área e consumo de matéria seca entre os tratamentos. A soma térmica como intervalo de descanso entre os pastoreios mostrou-se uma alternativa de manejo para aumentar a taxa de lotação.

ABSTRACT: The aim of this study was to evaluate the performance and feed intake of grazing beef heifers on two grazing intervals determined by thermal sum related to leaf elongation duration during cool season on natural grasslands. A complete randomized block design experiment with two treatments and three replications was conducted from May to September 2011 in the central part of the state of Rio Grande do Sul, Brazil. The treatments were two thermal sums calculated at 375 and 750 degrees-days (DD) to determine the intervals between grazing periods in a rotational grazing system. Thirty six beef heifers with average age of 18 months old and (initial body weight = 220±14kg) were used, all heifers received ground corn supplement at a rate of 5g kg-1 of body weight per day, at 2p.m., throughout the experiment and had free access to mineral and protein supplementation (450g kg-1 of CP). Similar average daily gain (ADG), beef production gain (BPG) and feed intake (FI), were obtained in both treatments. Leaf elongation duration is an alternative grazing management tool for improved animal production and to increase animal stocking rate.

ABSTRACT Bermudagrass (Cynodon dactylon cv. Jiggs) is an important food source for dairy cattle in the semi-intensive milk production systems most often used in southern Brazil. Although many insect pests are associated with feed grasses, we report here the first occurrence of the fly Atherigona (Atherigona) reversura Villeneuve, 1936 (Diptera: Muscidae) feeding on bermudagrass in Brazil. This potential pest was observed in April 2015 in three localities (Abelardo Luz, Palmitos, and Videira) in western Santa Catarina, in southern Brazil. The infested plants had senescent and necrotic terminal leaves that reduced plant growth. New growth had to sprout new tillers from basal nodes, which resulted in a reduced plant growth rate. We also provide a morphological identification key (with figures) for A. (Atherigona) reversura and A. (Acritochaeta) orientalis Schiner, 1868. A molecular identification based on COI is also provided to better differentiate species.

Foram testados os efeitos de dois intervalos de descanso entre pastoreios, 375 e 750 graus-dia, baseado na soma térmica para a expansão foliar de gramíneas nativas de dois grupos funcionais sobre o comportamento ingestivo de novilhas de corte. O delineamento foi em blocos ao acaso, com dois tratamentos, três repetições de área e medidas repetidas no tempo. Foram realizadas três avaliações (nov/11, jan e mar/12), com 24h cada, utilizando novilhas de corte com 12 meses. Estimou-se o consumo de forragem com marcador externo (Cr2O3). A massa de lâminas foliares foi semelhante entre os tratamentos, apresentando média de 1261kg MS ha-1. O tempo médio dispendido pelos animais em pastejo foi de 627,4 minutos e a taxa de bocados média foi de 37,1 bocados minuto-1. O número médio de refeições foi de 5,9 refeições dia-1, com uma média de 118,5 minutos por refeição. Os animais visitaram, em média, 6,1 estações alimentares por minuto e permaneceram nessas estações por 12 segundos. Houve diferença no tempo de pastejo e taxa de bocado nos períodos, com uma redução ao longo do tempo. Os intervalos de descanso testados provaram ter pouco efeito no comportamento ingestivo e no consumo de forragem das novilhas

It was evaluated the effect of two rest intervals between grazing occupations in rotational grazing; 375 and 750 DD (degree-days); based on the cumulative thermal sum necessary for leaf expansion of native grasses of two functional groups over the grazing behavior variables from beef heifers with 12 months old. The experiment was conducted as a completely randomized block design, with two treatments, three replications and measures repeated over time. Grazing behavior was assessed in three occasions (Nov 2011, Jan and Mar 2012), with 24h each. The herbage intake was estimated using an external marker (Cr2O3). The leaf mass was similar among the rest intervals, with a mean of 1261kg DM ha-1. The average grazing time was 627.4min day-1 and bite rate was 37.1 bites min-1. The average number of daily meals was 5.9 with an average of 118.5 minutes. Number of feeding stations visited per minute was 6.1 and the feeding stations permanence time was of 12 seconds. There was a reduction only on grazing time and bite rate over the periods. The range of thermal sums evaluated to define the rest intervals in rotational grazing proved no effect on heifers' grazing behavior and herbage intake

O objetivo foi avaliar o desempenho de novilhas de corte em pastagem natural sob pastoreio contínuo e rotativo no outono-inverno. Os tratamentos foram distribuídos em um delineamento inteiramente casualizado, conduzidos utilizando a massa de forragem acima de oito cm e 50% da massa de lâminas foliares das touceiras. Os animais foram novilhas Brangus com peso médio inicial de 258kg. As variáveis avaliadas foram massa de forragem disponibilizada (MFd), massa de lâminas foliares das touceiras (MLFt) oferta de forragem disponibilizada (OFd), altura do estrato inferior (Hinf), proteína bruta (PB), fibra em detergente neutro (FDN), digestibilidade da matéria orgânica (DISMO), nutrientes digestíveis totais (NDT), ganho médio diário (GMD), escore de condição corporal (CC), escore do trato reprodutivo (ETR) e taxa de lotação (TL). MFd, Hinf, DISMO e NDT foram decrescentes e OFd, PB e FDN semelhantes ao longo do período experimental. O GMD foi positivo apenas no terceiro período, enquanto que CC, ETR e TL decresceram. O manejo da pastagem natural sob pastoreio contínuo ou rotativo, no outono-inverno, utilizando a massa de forragem acima de oito cm e 50% da massa de lâminas foliares das touceiras, não possibilita o desenvolvimento corporal adequado para acasalamento de novilhas de corte aos 24 meses.

The aim of this study was to evaluate the performance of beef heifers in natural grassland under continuous and rotational grazing during the autumn-winter period. The treatments were distributed in a completely randomized design and conducted using the forage mass above eight cm and 50% of the leaf blades mass of tussocks. The animals were Brangus beef heifers with initial body weight of 258kg. The variables evaluated were available forage mass (FMa), leaf blades mass of tussocks (LBMt), real forage allowance (FAr), sward height of the lower stratum (HLS), crude protein (CP), neutral detergent fiber (NDF), organic matter digestibility (OMD), total digestible nutrients (TDN), average daily gain (ADG), body condition score (BCS), reproductive tract score (RTS) and stocking rate (SR). FMa, HLS, OMD and TDN decreased while FAr, CP and NDF were similar during the experimental period. The ADG was positive only at third experimental period while BCS, RTS and SR decreased over time. The natural grassland management under continuous and rotational grazing during the autumn-winter period, using the forage mass above 8cm and 50% of the leaf blades mass of tussocks, does not allow the adequate corporal development for breeding the beef heifers at 24 months old.

The aim of this study was to determine the degradation resistance of three new formulations-silorane-, Ormocer- and dimer-acid-based materials-and compare them to the traditional dimethacrylate-based materials. One silorane- (Filtek P90, P90), one Ormocer- (Ceram-X, CX), one dimer-acid- (N'Durance, ND) and two dimethacrylate-based (Filtek P60, P60; Tetric Ceram, TC) materials were investigated. Water sorption (Wsp) and solubility (Wsl) were determined after the materials were immersed in water for 28 days. Knoop hardness (KH) was determined before and after 24 h immersion in pure ethanol. The flexural-strength (FS) was determined by the bending test after one-week storage in a dry environment or after one-week immersion in pure ethanol. Data were submitted to analysis of variance (ANOVA) and Tukey's test (95%). The three new formulations showed lower Wsp than the dimethacrylate-based formulation. CX (0.50 ± 0.17%) and ND (0.72 ± 0.19%) exhibited the lowest Wsp, whereas P90 (0.02 ± 0.03%) and P60 (0.04 ± 0.03%) showed the lowest Wsl. All resins showed reduced Knoop hardness number (KHN) after ethanol immersion. P60 presented the lowest decrease in KH value (19 ± 5%). TC (48 ± 3%) and P90 (39 ± 9%) showed the highest KHN decrease after ethanol storage. The FS of CX, ND and TC were affected by ethanol storage. The new formulations did not improve the degradation resistance, as compared with the traditional methacrylate-based materials.

Este estudo foi realizado para avaliar o desempenho de cordeiras Texel × Ile de France em pastagem de milheto (Pennisetum americanum (L.) Leeke) recebendo suplementação com farinha de mandioca ou glúten de milho. O delineamento experimental foi inteiramente casualizado, com três tratamentos (estratégias alimentares) e duas repetições de área. As estratégias alimentares consistiram da suplementação da pastagem com farinha de mandioca ou glúten de milho em comparação à pastagem exclusiva. Os suplementos foram fornecidos diariamente, às 9 h, em quantidade equivalente a 1% do peso vivo (PV). As cordeiras sob suplementação com glúten de milho apresentaram maior ganho de peso diário e por área. A utilização de suplementos, no entanto, não permitiu aumentar a taxa de lotação da pastagem. A digestibilidade in vitro e a composição bromatológica da forragem colhida foi semelhante (proteína bruta, fibra em detergente neutro) entre os grupos. Ao final do experimento, todas as estratégias alimentares foram eficientes para promover pesos superiores a 60% do peso adulto, indicando que as cordeiras estão aptas para o início do encarneiramento. O escore de condição corporal (ECC) das cordeiras sob suplementação com farinha de mandioca foi de 3,0, enquanto o das demais foi 2,8. O uso exclusivo de pastagem de milheto é capaz de suprir as exigências de matéria seca de cordeiras.

The objective of this study was to evaluate the performance of Texel × Ile de France female hoggets on pearl millet (Pennisetum americanum (L.) Leeke) pastures fed supplementation with cassava meal or corn gluten. It was used a completely randomized experimental design, with three treatments (feed strategies) and two area replications. Feed strategies consisted of supplementation of the pastures with cassava meal or corn gluten in comparison to exclusive pasture. Supplements were given daily at 9:00 a.m. at quantity of 1% of the body weight (BW). The lambs on corn gluten supplementation presented greater daily weight gain and greater per area weight gain. Use of supplementation did not permit to increase pasture stocking rate, however. In vitro digestibility and chemical composition of the harvested forage was similar (crude protein, neutral detergent fiber) among groups. At the end of the experiment, all feed strategies were efficient in promoting weight greater than 60% of the mature weight, showing that the lambs are able for mating. Body condition score (BCS) of lambs under cassava meal supplementation was 3.0 whereas body composition score of the other lambs was 2.8. Exclusive use of pearl millet can provide dry matter requirement of the lambs.

The aim of this study was to evaluate: (i) the absorption of photo-initiators and emission spectra of light curing units (LCUs); and (ii) the degree of conversion (DC) of experimental composites formulated with different photo-initiators when activated by different LCUs. Blends of BisGMA, UDMA, BisEMA and TEGDMA with camphorquinone (CQ) and/ or 1-phenyl-1,2-propanedione (PPD) were prepared. Dimethylaminoethyl methacrylate (DMAEMA) was used as co-initiator. Each mixture was loaded with 65 wt% of silanated filler particles. One quartz-tungsten-halogen - QTH (XL 2500, 3M/ESPE) and two lightemitting diode (LED) LCUs (UltraBlue IS, DMC and UltraLume LED 5, Ultradent) were used for activation procedures. Irradiance (mW/cm²) was calculated by the ratio of the output power by the area of the tip, and spectral distribution with a spectrometer (USB 2000). The absorption curve of each photo-initiator was determined using a spectrophotometer (Varian Cary 5G). DC was assessed by Fourier transformed infrared spectroscopy. Data were submitted to two-way ANOVA and Tukey's test (5%). No significant difference was found for DC values when using LED LCUs regardless of the photo-initiator type. However, PPD showed significantly lower DC values than composites with CQ when irradiated with QTH. PPD produced DC values similar to those of CQ, but it was dependent on the LCU type.

Avaliaram-se o comportamento ingestivo e o consumo de matéria seca de cordeiras recebendo diferentes tipos de suplemento em pastagem de milheto (Pennisetum americanum (L.) Leeke). Foram utilizadas 24 cordeiras com peso inicial de 30,2 ± 2,6 kg, distribuídas em três estratégias alimentares: pastagem de milheto exclusivamente; pastagem de milheto e suplementação com farinha de mandioca; e pastagem de milheto e suplementação com glúten de milho. Os suplementos foram fornecidos na quantidade de 1% do PV. Foram avaliados, em três datas, os tempos diários (min/dia) de pastejo, ruminação e ócio e a taxa de bocados (boc/min) das cordeiras. O consumo de matéria seca (CMS) foi estimado pela relação entre a produção fecal e a indigestibilidade da matéria seca e a digestibilidade da MS, pelo método in vitro. A estimativa da excreção fecal foi realizada utilizando-se óxido de cromo como marcador externo. O delineamento experimental foi o inteiramente casualizado, com três estratégias alimentares, duas repetições de área e quatro animais-teste por repetição. O fornecimento de suplementos diminuiu o tempo de pastejo diário, a taxa de bocados e a massa de bocado. A ingestão de pasto foi menor entre as cordeiras que receberam glúten de milho que entre aquelas mantidas exclusivamente a pasto, todavia, a ingestão total de MS foi maior quando fornecidos os suplementos (947 g para suplementação com glúten de milho; 907 g para suplementação com farinha de mandioca; e 652 g para pastagem exclusiva). Cordeiras em pastagem de milheto sem suplementação permanecem mais tempo em pastejo.

The feeding behavior and dry forage intake of ewe lambs receiving different types of supplementation on pearl millet (Pennisetum americanum (L.) Leeke) pasture was evaluated. Twenty-four ewe lambs with 30.2 ± 2.6 kg mean initial body weight (BW), distributed in three feeding strategies: grazing on pearl millet pasture; grazing on pearl millet pasture supplemented with cassava meal; and GL - grazing on pearl millet pasture supplemented with corn gluten meal. Supplements were provided in the amount of 1% of BW. The daily times (min/day) spent grazing, ruminating and idling, and the biting rate (bites/min) were evaluated on three dates. The dry matter intake (DMI) was estimated from the relationship between the fecal production (FC, g/day) and dry matter indigestibility by the in vitro method. The fecal excretion was estimated using chomium oxide as an outside marker. A randomized complete design was used, with three feeding strategies, two area replications and four tester animals per replication. Providing supplements decreased the daily grazing time, bite rate and bite mass. Pasture intake was lower among ewe lambs that received corn gluten than for those kept exclusively on pasture; however, dry matter total intake was higher when supplement fed (947 g for corn gluten supplementation; 907 g for cassava meal supplementation; and 652 g for exclusive pasture). Ewe lambs on pearl millet pasture without supplementation keep on grazing for more time.

Foi avaliado o crescimento alométrico de ossos, músculos e gordura, e das regiões da carcaça de cordeiros Texel × Ile de France, terminados em confinamento. Vinte cordeiros, machos não-castrados, foram desmamados aos 42 dias de idade (15,9 ± 2,1kg de peso vivo) e confinados em baias individuais recebendo alimentação ad libitum. Destes, cinco foram abatidos 10 dias após o desmame e, os remanescentes, aos 25, 30 ou 35kg de peso vivo. Para determinação do crescimento alométrico dos cortes e tecidos foi utilizada a equação exponencial Y = aXb, transformada logaritmicamente em um modelo linear. Observou-se crescimento precoce (b = 0,89) da paleta, ao passo que a perna, a costela e o pescoço apresentaram crescimento isogônico (b = 1,00, 1,03 e 1,11, respectivamente), ou seja, equivalente ao da carcaça. O aumento do peso da carcaça implicou em redução da taxa de crescimento de ossos e músculos (b = 0,60 e 0,92, respectivamente) e aumento da taxa de crescimento da gordura (b = 1,78). O crescimento muscular foi diferenciado nas distintas regiões da carcaça, sendo isogônico na paleta (b = 0,98) e na perna (b = 0,99) e precoce na costela (b = 0,90) e no pescoço (b = 0,79). Recomenda-se que o abate de cordeiros Texel × Ile de France seja realizado com, no máximo, 30kg de peso vivo.

Allometric growth of bone, muscle and fat, as well as of the carcass cuts of feedlot Texel × Ile de France crossbred lambs was evaluated. Twenty non-castrated male lambs weaned at 42 days of age (15.9 ± 2.1kg live weight) were housed in individual stalls and fed ad libitum. Five lambs were slaughtered ten days after weaning, and the remaining were randomly assigned to one of three slaughter weights: 25, 30 and 35kg live weight. To determine allometric growth of individual cuts and tissues, exponential equation Y = aXb was logarithmically transformed and used. Shoulder presented early maturity (b = 0.89), whereas allometric growth of leg, rib and neck were isogonics (b = 1.00, 1.03 e 1.11, respectively), i.e., similar to the carcass. Increased carcass weight resulted in decreased rate of bone and muscle growth (b = 0.60 and 0.92, respectively), and increased rate of fat growth (b = 1.78). Muscle growth was different among carcass cuts, being isogonics in shoulder (b = 0.98) and leg (b = 0.99), and early in rib (b = 0.90) and neck (b = 0.79). Maximum slaughter weight of Texel × Ile de France crossbred lambs is recommended to be 30kg live weight.

O objetivo do trabalho foi avaliar o efeito do fornecimento de dietas com diferentes níveis de fibra em detergente neutro (FDN) sobre o comportamento ingestivo de ovelhas em lactação. Foram utilizadas 18 ovelhas 5/8 Ile de France 3/8 Texel, confinadas 24 horas após o parto em baias individuais, sendo aleatoriamente distribuídas em três tratamentos: 34, 43 e 52% de FDN na dieta. As dietas, isoproteicas, foram compostas por silagem de milho (Zea mays L.), milho triturado, farelo de soja (Glycine max L.), calcário calcítico, fosfato bicálcico e sal comum, sendo fornecidas ad libitum, duas vezes ao dia, em horários pré-estabelecidos às 8h30min e 16h30min. O comportamento ingestivo dos animais foi determinado mediante apreciação visual. O aumento do nível de FDN na dieta influenciou significativamente os consumos de MS e FDN, a produção de leite e os tempos despendidos em ingestão, ruminação, ócio e mastigação total, que variaram de forma quadrática (P<0,05). As eficiências de ingestão e ruminação de FDN, expressas em g h-1, aumentaram (P<0,05), ao passo que as eficiências de ingestão e ruminação de MS decresceram linearmente (P<0,05) com o incremento do nível de FDN da dieta, sendo necessário maior período de tempo para ingerir e ruminar uma mesma quantidade de alimento. Altos níveis de FDN na dieta podem acarretar depressão do consumo de matéria seca.

The aim of this study was to evaluate the effects of different neutral detergent fiber (NDF) levels in the diet on ingestive behavior of lactating ewes. Eighteen 5/8 Ile de France 3/8 Texel ewes, housed in individual cage 24 hours postpartum, were used. Animals were assigned to one of three treatments: 34, 43 and 52% NDF in the diet, in dry matter (DM) basis. The total mixed rations, composed by corn silage (Zea mays L.), ground corn, soybean meal (Glycine max L.), limestone, salt and dicalcium phosphate, were given twice a day, at 0830 AM and 0430 PM. Ingestive behavior was determined by visual appreciation. The increase of the NDF level in the diet significantly influenced (P<.05) DM and NDF intakes, milk yield, and the feeding, rumination, idleness resting and total chewing times, that varied quadratically (P<.05). The NDF feeding and rumination efficiency increased, whereas DM feeding and rumination efficiency linearly decreased (P<.05) as effect of the NDF increased, being necessary more time to feed the same amount of total mixed ration. Highest NDF levels in the diet can cause depression in DM intake.

This study investigated the influence of ethanol concentration on softening tests for cross-link density evaluation (microhardness) of dental composites. Specimens of Filtek Z100 (3M ESPE) were light-activated by standard or pulse-delay methods. After initial Knoop hardness readings (KHN1), half of specimens (n = 10) for each irradiation method was stored in 100% ethanol, and half in 75% ethanol, during 24 hours, and hardness was determined anew. Hardness deterioration (DKHN) was recorded as the difference between pre and post-storage values. KHN1 data were submitted to one-way ANOVA and Tukey's test (alpha = 0.05), and hardness deterioration was analyzed by two-way ANOVA and Tukey's test (alpha= 0.05). For KHN1, no significant differences were detected between the activation modes (p = 0.697). Samples light-activated by the pulse-delay method presented significantly higher softening compared to the standard mode when samples were immersed in 100% ethanol. Conversely, no significant differences between curing modes were detected for samples stored in 75% ethanol.

Este estudo foi conduzido no Departamento de Zootecnia da Universidade Federal de Santa Maria, RS, no período de agosto a dezembro de 2003. O objetivo foi avaliar o consumo de nutrientes e o desempenho de cordeiros machos, não castrados, cruzados Ile de France x Texel, submetidos a quatro níveis de fibra em detergente neutro (FDN): 25%, 31%, 37% e 43%. O volumoso utilizado foi a silagem de sorgo híbrido (AG 2005 E) e o concentrado foi composto de milho em grão triturado, farelo de soja, sal comum, calcário calcítico e fosfato bicálcico. As dietas dos quatro tratamentos eram isoprotéicas, contendo 17% de proteína bruta. Foram utilizados 20 cordeiros desmamados em média aos 42 dias de idade e abatidos quando atingiram 30kg de peso vivo. O delineamento experimental foi o inteiramento casualizado, com quatro tratamentos e cinco repetições. Foram avaliados os consumos de nutrientes, o ganho de peso médio diário (GMD), a conversão alimentar (CA) e o número de dias que os cordeiros levaram para atingir o peso vivo ao abate de 30kg. A adição de níveis crescentes de FDN à dieta ocasionou um decréscimo linear nos consumos de matéria seca, matéria orgânica, proteína bruta, extrato etéreo, carboidratos totais e carboidratos não estruturais. Por outro lado, aumentou linearmente o consumo de fibra em detergente neutro e fibra em detergente ácido. Verificou-se redução linear do GMD e piora na CA com o aumento do teor de fibra na ração, o que proporcionou uma elevação linear no número de dias que os cordeiros levaram para atingir o peso de abate.

This study was conducted at the Animal Science Department of Federal University of Santa Maria, RS, from August to December 2003. The aim was to evaluate the food intake and performance of male lambs, non-castrated, crossbreed Ile de France x Texel, submitted to four levels of NDF: 25%, 31%, 37% and 43%. The roughage used was a hybrid sorghum silage (AG 2005 E) and the concentrate was composed of ground corn, soybean meal, common salt, limestone and dicalcium phosphate. The four diets were isoproteic with 17% of crude protein. Twenty lambs, with an average of 42 days old were used in the experiment and slaughtered when they reach 30kg live weight. The experimental design was completely ramdomized, with four treatments and five replications. The intake of nutrients, daily average weigh gain (DWG) feed conversion (FC) and the number of days to the reachr 30kg of live weight were evaluated. The addition of increasing levels of NDF to the diet caused a linear decrease in the intake of dry matter (DMI), organic matter (OMI), crude protein (CPI), ethereal extract (EEI), total carbohydrates (TCHOI) and non-structural carbohydrates (NSCI). On the other hand, the consumption of neutral detergent fiber (NDFI) and acid detergent fiber (ADFI) increased linearly with the increase of NDF in the diets. The increase of the fiber level in the diet resulted in linear reduction in DWG and in FC, which caused a linear increase in the amount of days to lambs reach the slaughter weight.

Este estudo teve como objetivo avaliar o efeito do aumento da densidade de energia na dureza Knoop das resinas compostas Z250 e Esthet-X. Cavidades cilíndricas (3 mm de diâmetro X 3mm de profundidade) foram preparadas na superfície vestibular de 144 incisivos bovinos. As resinas compostas foram inseridas em incremento único e fotopolimerizadas com diferentes unidades e tempos de fotopolimerização: luz halógena convencional (700 mW/cm²; 20 s, 30 s and 40 s); LED (diodo emissor de luz; 440 mW/cm²; 20 s, 30 s and 40 s); PAC (arco de plasma de xenônio; 1700 mW/cm²; 3 s, 4,5 s and 6 s). Os espécimens foram armazenados a 37°C durante 24 h, previamente à realização das leituras de dureza Knoop. Foram realizadas três leituras por profundidade: superfície, 1 mm e 2 mm. Os dados foram submetidos à ANOVA e ao teste de Tukey (p<0,05). Independente da unidade de fotopolimerização ou da densidade de energia, a dureza do compósito Z250 foi estatisticamente superior do que o compósito Esthet-X (p<0.05). A dureza dos compósitos fotoativados por PAC foi estatisticamente inferior em relação aos compósitos fotoativados por luz halógena ou LED (p<0.05) que, por sua vez, não diferiram entre si, independentemente da profundidade. O aumento do tempo de exposição produziu compósitos com maiores valores de dureza Knoop quando se utilizou LED ou PAC (p<0.05). Para luz halógena o aumento do tempo de exposição não influenciou os valores de dureza (p>0.05). Os valores de dureza Knoop diminuíram com o aumento da profundidade. O aumento da densidade de energia produziu compósitos com maior dureza Knoop quando o LED e o PAC foram utilizados como fontes de polimerização.

The aim of this study was to evaluate the effect of the increase of energy density on Knoop hardness of Z250 and Esthet-X composite resins. Cylindrical cavities (3 mm in diameter X 3 mm in depth) were prepared on the buccal surface of 144 bovine incisors. The composite resins were bulk-inserted and polymerized using different light-curing units and times: conventional QTH (quartz-tungsten-halogen; 700 mW/cm²; 20 s, 30 s and 40 s); LED (light-emitting diode; 440 mW/cm²; 20 s, 30 s and 40 s); PAC (xenon plasma arc; 1700 mW/cm²; 3 s, 4.5 s and 6 s). The specimens were stored at 37°C for 24 h prior to sectioning for Knoop hardness assessment. Three measurements were obtained for each depth: top surface, 1 mm and 2 mm. Data were analyzed statistically by ANOVA and Tukey's test (p<0.05). Regardless of the light source or energy density, Knoop hardness of Z250 was statistically significant higher than that of Esthet-X (p<0.05). Specimens cured with PAC had lower hardness than those cured with QTH and LED (p<0.05). Higher Knoop hardness was obtained when the energy density was increased for LED and PAC (p<0.05). No statistically significant differences (p>0.05) were found for QTH. Knoop hardness values decreased with the increase of depth. The increase of energy density produced composites with higher Knoop hardness means using LED and PAC.