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Two randomized complete block design experiments were conducted to evaluate the effect of bedding use in confined beef steers. Experiment 1 used Simmental &times, Angus steers (n = 240, initial body weight (BW) = 365 &plusmn, 22.5 kg). Experiment 2 used newly weaned Charolais &times, Red Angus steers (n = 162, initial BW = 278 &plusmn, 13.4 kg). Steers were allotted to one of two treatments: (1) no bedding (NO), or (2) 1.8 kg (Experiment 1) or 1.0 kg (Experiment 2) of wheat straw (as-is basis) bedding/steer&middot, d&minus, 1 (BED). In Experiment 1, applying bedding improved (p &le, 0.01) dry matter intake (DMI), kg of gain to kg of feed (G:F), and average daily gain (ADG). Bedding reduced (p = 0.01) the estimated maintenance coefficient (MQ). Dressing percentage, rib fat, marbling, and yield grade were increased (p &le, 0.03) in NO. Bedding resulted in an increase (p = 0.01) in serum insulin-like growth factor I (IGF-I). In Experiment 2, a tendency (p = 0.06) for increased DMI for NO was noted. Bedding improved G:F (p = 0.01). MQ was elevated (p = 0.03) for NO and NO had an increase (p = 0.02) in serum concentration of urea-N (SUN). An increase (p = 0.01) in serum non-esterified fatty acid was noted for NO. These data indicate that bedding applications should be considered to improve growth performance and feed efficiency by reducing maintenance energy requirements in beef steers during the feedlot receiving and finishing phase.

For biogas-producing continuous stirred tank reactors, an increase in dilution rate increases the methane production rate as long as substrate input can be converted fully. However, higher dilution rates necessitate higher specific microbial growth rates, which are assumed to have a strong impact on the apparent microbial biomass yield due to cellular maintenance. To test this, we operated two reactors at 37°C in parallel at dilution rates of 0.18 and 0.07 days-1 (hydraulic retention times of 5.5 and 14 days, doubling times of 3.9 and 9.9 days in steady state) with identical inoculum and a mixture of volatile fatty acids as sole carbon sources. We evaluated the performance of the Anaerobic Digestion Model No. 1 (ADM1), a thermodynamic black box approach (TBA), and dynamic flux balance analysis (dFBA), to describe the experimental observations. All models overestimated the impact of dilution rate on the apparent microbial biomass yield when using default parameter values. Based on our analysis, a maintenance coefficient value below 0.2 kJ per carbon mole of microbial biomass per hour should be used for the TBA, corresponding to 0.12 mmol ATP per gram dry weight per hour for dFBA, which strongly deviates from the value of 9.8 kJ Cmol h-1 that has been suggested to apply to all anaerobic microorganisms at 37°C. We hypothesized that a decrease in dilution rate might select taxa with minimized maintenance expenditure. However, no major differences in the dominating taxa between the reactors were observed based on amplicon sequencing of 16S rRNA genes and terminal restriction fragment length polymorphism analysis of mcrA genes. Surprisingly, Methanosaeta dominated over Methanosarcina even at a dilution rate of 0.18 days-1, which contradicts previous model expectations. Furthermore, only 23–49% of the bacterial reads could be assigned to known syntrophic fatty acid oxidizers, indicating that unknown members of this functional group remain to be discovered. In conclusion, microbial maintenance was found to be much lower for acetogenesis and methanogenesis than previously assumed, likely due to the exceptionally low growth rates in anaerobic digestion. This finding might also be relevant for other microbial systems operating at similarly low growth rates.

Bioenergetic analysis of the growth of the binary mixed culture (Pseudomonas aeruginosa and Pseudomonas fluorescence) on phenol chemostat culture was carried out. The data were checked for consistency using carbon and available electron balances. When more than the minimum number of variables are measured, and measurement errors are taken into account, the results of parameter estimation depend on which of the measured variables are chosen for this purpose. Similar parameter estimates were obtained using Pirt’s model based on the Monod equation approach and a modified model based on substrate consumption being rate limiting. Coupled with the covariate adjustmentestimation technique, the best estimates were the maximum likelihood estimates (MLE) based on when all the measured data were used. For the aerobic growth of the mixed culture on phenol, ηmax = 0.396 and me= −0.020 h-1. From the 95% confidence intervals, a maximum of about 38 – 41.3% of the energy contained in phenol is incorporated into the mixed culture biomass. The balance (58.7 – 62%) is evolved as heat with little or no energy needed for the maintenance of organisms.Keywords: Binary mixed culture, biomass energetic yield, chemostat culture, energetic analysis, maintenance coefficient, Pirt’s model

In this study a comparative analysis of three Corynebacterium glutamicum ATCC 13032 respiratory chain mutants lacking either the cytochrome bd branch (ΔcydAB), or the cytochrome bc1–aa3 branch (Δqcr), or both branches was performed. The lack of cytochrome bd oxidase was inhibitory only under conditions of oxygen limitation, whereas the absence of a functional cytochrome bc1–aa3 supercomplex led to decreases in growth rate, biomass yield, respiration and proton-motive force (pmf) and a strongly increased maintenance coefficient under oxygen excess. These results show that the bc1–aa3 supercomplex is of major importance for aerobic respiration. For the first time, a C. glutamicum strain with a completely inactivated aerobic respiratory chain was obtained (ΔcydABΔqcr), named DOOR (devoid of oxygen respiration), which was able to grow aerobically in BHI (brain–heart infusion) glucose complex medium with a 70% reduced biomass yield compared to the wild type. Surprisingly, reasonable aerobic growth was also possible in glucose minimal medium after supplementation with peptone. Under these conditions, the DOOR strain displayed a fermentative type of catabolism with l-lactate as major and acetate and succinate as minor products. The DOOR strain had about 2% of the oxygen consumption rate of the wild type, showing the absence of additional terminal oxidases. The pmf of the DOOR mutant was reduced by about 30% compared to the wild type. Candidates for pmf generation in the DOOR strain are succinate:menaquinone oxidoreductase, which probably can generate pmf in the direction of fumarate reduction, and F1FO-ATP synthase, which can couple ATP hydrolysis to the export of protons.

O rio Tapajós é o principal rio da sub-bacia 17 e é formado, principalmente, pelo rio Jurena e rio Teles Pires. O Rio Juruena nasce na Chapada dos Parecis, no município de Vila Bela da Santíssima Trindade, estado de Mato Grosso. Seus principais afluentes pela margem direita são: os rios Arinos, do sangue, Papagaio, São João da Barra e São Tomé, e pela margem esquerda os rios: Juína, Camaré, Urugatos e Bararati. O Rio Teles Pires ou São Manoel nasce na Serra Azul, município de Chapada dos Guimarães, estado de Mato Grosso. São seus afluentes pela margem direita os rios: Caiapó, Tabatinga, Parado, Peixoto de Azevedo e Cururu-Açú, e pela margem esquerda os rios: Verde, Paranaíba, Apiaça e Santa Rosa. O estudo também engloba o rio Jamanxim.

O estudo abrange a parte Oeste do estado de São Paulo e a parte Leste do estado do Mato Grosso do Sul e os seguintes municípios: Água Clara, Anaurilândia, Bandeirantes, Bataguassu, Brasilândia, Camapuã, Campo Grande, Cassilândia, Chapadão do Sul, Costa Rica, Presidente Epitácio, Presidente Prudente, Presidente Venceslau, Promissão, Quatá, Queiroz, Quintana, Rancharia, Regente Feijó, Ribeirão dos Índios, Inocência, Rinópolis, Rosana, Rubiácea, Sagres, Salmourão, Santa Mercedes, Santo Anastácio, Santo Expedito, Santópolis do Aguapeí, São João do Pau d`Alho, Jaraguari, Teodoro Sampaio, Tupã, Tupi Paulista, Valparaíso, Vera Cruz, Nova Alvorada do Sul, Nova Andradina, Ribas do Rio Pardo, Santa Rita do Pardo, Selvíria, Sidrolândia, Três Lagoas, Adamantina, Alfredo Marcondes, Alto Alegre, Alvaro Machado, Alvinlândia, Andradina, Anhumas, Araçatuba, Arco-Iris, Bastos, Bento de Abreu, Bilac, Bora, Braúna, Cafelândia, Caiabu, Caiaua, Castilho, Clementina, Coroados, Dracena, Echopora, Emilianópolis, Euclides da Cunha Paulista, Flora Rica, Florida Paulista, Gabriel Monteiro, Galia, Garça, Getulina, Guaiçara, Gauimbe, Guaraçaí, Guarantã, Herculândia, Iacri, Indiana, Inubia Paulista, Irapuru, Itaurã, João Ramalho, Julio Mesquita, Junqueirópolis, Lavínia, Lins, Lutécia, Maraba Paulista, Mariápolis, Marília, Martinópolis, Mirandópolis, Mirante do Paranapanema, Monte Castelo, Murutinga do Sul, Nova Guataporanga, Nova Independência, Ocauçu, Oriente, Oscar Bressane, Osvaldo Cruz, Ouro Verde, Pacaembu, Panorama, Paraguaçu Paulista, Parapuã, Pauliceia, Penápolis, Piacatu, Piquerobi, Pirajuí, Pirapozinho, Pompéia, Pracinha, Presidente Alves e Presidente Bernardes. E os seguintes rios: Rio Anhaduí, Rio Anhanduzinho, Rio do Peixe, Rio Feio, Rio Aguapei, Rio Pardo, Rio Santo Anastácio, Rio Sucuriú e Rio Verde.

O estudo abrange a parte Oeste do estado de São Paulo e a parte Leste do estado do Mato Grosso do Sul e os seguintes municípios: Água Clara, Anaurilândia, Bandeirantes, Bataguassu, Brasilândia, Camapuã, Campo Grande, Cassilândia, Chapadão do Sul, Costa Rica, Presidente Epitácio, Presidente Prudente, Presidente Venceslau, Promissão, Quatá, Queiroz, Quintana, Rancharia, Regente Feijó, Ribeirão dos Índios, Inocência, Rinópolis, Rosana, Rubiácea, Sagres, Salmourão, Santa Mercedes, Santo Anastácio, Santo Expedito, Santópolis do Aguapeí, São João do Pau d`Alho, Jaraguari, Teodoro Sampaio, Tupã, Tupi Paulista, Valparaíso, Vera Cruz, Nova Alvorada do Sul, Nova Andradina, Ribas do Rio Pardo, Santa Rita do Pardo, Selvíria, Sidrolândia, Três Lagoas, Adamantina, Alfredo Marcondes, Alto Alegre, Alvaro Machado, Alvinlândia, Andradina, Anhumas, Araçatuba, Arco-Iris, Bastos, Bento de Abreu, Bilac, Bora, Braúna, Cafelândia, Caiabu, Caiaua, Castilho, Clementina, Coroados, Dracena, Echopora, Emilianópolis, Euclides da Cunha Paulista, Flora Rica, Florida Paulista, Gabriel Monteiro, Galia, Garça, Getulina, Guaiçara, Gauimbe, Guaraçaí, Guarantã, Herculândia, Iacri, Indiana, Inubia Paulista, Irapuru, Itaurã, João Ramalho, Julio Mesquita, Junqueirópolis, Lavínia, Lins, Lutécia, Maraba Paulista, Mariápolis, Marília, Martinópolis, Mirandópolis, Mirante do Paranapanema, Monte Castelo, Murutinga do Sul, Nova Guataporanga, Nova Independência, Ocauçu, Oriente, Oscar Bressane, Osvaldo Cruz, Ouro Verde, Pacaembu, Panorama, Paraguaçu Paulista, Parapuã, Pauliceia, Penápolis, Piacatu, Piquerobi, Pirajuí, Pirapozinho, Pompéia, Pracinha, Presidente Alves e Presidente Bernardes. E os seguintes rios: Rio Anhaduí, Rio Anhanduzinho, Rio do Peixe, Rio Feio, Rio Aguapei, Rio Pardo, Rio Santo Anastácio, Rio Sucuriú e Rio Verde.

Os principais rios da bacia do Rio Doce são: rio Doce, rio Piranga, rio Manhuaçu, rio Santo Antônio, rio Piracicaba, rio Caratinga, rio Casca, rio Suaçuí Pequeno, rio Guandu, rio Panças, rio Santa Maria,rio Resplendor e rio do Carmo

Carbon dioxide efflux rates (CER) of stems and roots of overstory and understory black cherry (Prunus serotina Ehrh., BC), red maple (Acer rubrum L., RM) and northern red oak (Quercus rubra L., RO) trees were monitored over two growing seasons at two contrasting sites in the Great Smoky Mountains to investigate diurnal and seasonal patterns in respiration and to develop prediction models based on environmental and plant parameters. CER of small roots (din situ measurements by using permanently installed flexible cuvettes. Temperature-adjusted CER of roots showed no diel variation. The moderate long-term changes occurred simultaneously in all species and size classes, suggesting that they were driven mostly by environmental factors. Mean root CER ranged from 0.5 to 4.0 nmol g⁻¹ d.w. s⁻¹. Rates were up to six times higher for fine roots (d10 cm) and twigs (dD·lnd, with D between 1.2 and 1.8. A new, scale-invariant measure of CER, based on D, facilitated comparisons across diameters. Q₁₀ varied with the method of determination, and it was higher in spring (1.8-2.5) than in autumn (1.4-1.5) for all species. Daytime bole CER often fell below temperature-based predictions, likely due to transpiration. The reduction (usually ±50%) deviations from the predictions. Deviations were higher in the canopy than in the understory. Mean bole maintenance respiration (at 20°C and d=20 cm) was 0.66, 0.43 and 0.50 μMol m⁻¹, while the volume-based growth coefficient was around 5, 6 and 8 mol cm⁻³ for BC, RM and RO, respectively. In a controlled study, BC and RM seedlings were fumigated in open-top chambers with sub-ambient, ambient and twice-ambient levels of ozone. The twice-ambient treatment reduced stem CER in BC by 50% (p=0.05) in July, but there was no treatment effect in September or in RM. Ozone reduced root/shoot ratio and diameter growth in BC, and Pmax in both species. Ph. D.

Solid-state fermentation (SSF) is defined as the growth of microbes without a free-flowing aqueous phase. The feasibility of using a citrus peel for producing pectinase and xylanase via the SSF process by Aspergillus niger F3 was evaluated in a 2kg bioreactor. Different aeration conditions were tested to optimize the pectinase and xylanase production. The best air flow intensity was 1VkgM (volumetric air flow per kilogram of medium), which allowed a sufficient amount of O2 for the microorganism growth producing 265U/g and 65U/g pectinases and xylanases, respectively. A mathematical model was applied to determine the different kinetic parameters related to SSF. The specific growth rate and biomass oxygen yield decreased during fermentation, whereas an increase in the maintenance coefficient for the different employed carbon sources was concurrently observed.