The well-modulated lobster: The roles of serotonin,octopamine, and proctolin in the lobster nervous system     

Edward A. Kravitz  Barbara Beltz  Silvio Glusman  Michael Goy  Ronald Harris-Warrick  Michael Johnston  Margaret Livingstone  Thomas Schwarz 《Pesticide biochemistry and physiology》1984,22(2):133-147

Two amines, serotonin and octopamine, and a pentapeptide, proctolin, function as neurohormones in the lobster nervous system. This review article summarizes findings from this laboratory on: (i) the biosynthesis and further metabolism of the amines; (ii) the localization of amines at a cellular level using immunocytochemical methods; (iii) the physiological effects of the amines and proctolin on exoskeletal muscles and preliminary studies of the molecular basis of these effects; and (iv) explorations on the actions of amines on motoneurons of the ventral nerve cord that show that amines direct the readout of central motor programs for flexion and extension.  相似文献   

Revision of the Neotropical Exoristini (Diptera,Tachinidae): The status of the genera Epiplagiops and Tetragrapha     

Silvio S. Nihei 《Journal of insect science (Online)》2015,15(1)

The monotypic genera Epiplagiops Blanchard, 1943 and Tetragrapha Brauer and Bergenstamm, 1891 are revised. Both are invalidated and synonymized with Chetogena Rondani, 1856. Their type-species, Epiplagiops littoralis Blanchard, 1943 and Tetragrapha tessellata Brauer and Bergenstamm, 1891, are studied, redescribed, illustrated, and transferred to Chetogena. A lectotype is designated for T. tessellata.  相似文献   

Sequestering Ability of Phytate toward Biologically and Environmentally Relevant Trivalent Metal Cations     

C Bretti  RM Cigala  G Lando  D Milea  S Sammartano 《Journal of agricultural and food chemistry》2012,60(33):8075-8082

Quantitative parameters for the interactions between phytate (Phy) and Al(3+), Fe(3+), and Cr(3+) were determined potentiometrically in NaNO(3) aqueous solutions at I = 0.10 mol L(-1) and T = 298.15 K. Different complex species were found in a wide pH range. The various species are partially protonated, depending on the pH in which they are formed, and are indicated with the general formula MH(q)Phy (with 0 ≤ q ≤ 6). In all cases, the stability of the FeH(q)Phy species is several log K units higher than that of the analogous AlH(q)Phy and CrH(q)Phy species. For example, for the MH(2)Phy species, the stability trend is log K(2) = 15.81, 20.61, and 16.70 for Al(3+), Fe(3+), and Cr(3+), respectively. The sequestering ability of phytate toward the considered metal cations was evaluated by calculating the pL(0.5) values (i.e., the total ligand concentration necessary to bind 50% of the cation present in trace in solution) at different pH values. In general, phytate results in a quite good sequestering agent toward all three cations in the whole investigated pH range, but the order of pL(0.5) depends on it. For example, at pH 5.0 it is pL(0.5) = 5.33, 5.44, and 5.75 for Fe(3+), Cr(3+), and Al(3+), respectively (Fe(3+) < Cr(3+) < Al(3+)); at pH 7.4 it is pL(0.5) = 9.94, 9.23, and 8.71 (Al(3+) < Cr(3+) < Fe(3+)), whereas at pH 9.0 it is pL(0.5) = 10.42, 10.87, and 8.34 (Al(3+) < Fe(3+) < Cr(3+)). All of the pL(0.5) values, and therefore the sequestering ability, regularly increase with increasing pH, and the dependence of pL(0.5) on pH was modeled using some empirical equations.  相似文献   

Prevalence of <Emphasis Type="Italic">Toxoplasma gondii</Emphasis> and <Emphasis Type="Italic">Neospora caninum</Emphasis> infections in sheep from Federal District,central region of Brazil   总被引：1，自引：1，他引：0  

Ueno TE  Gonçalves VS  Heinemann MB  Dilli TL  Akimoto BM  de Souza SL  Gennari SM  Soares RM 《Tropical animal health and production》2009,41(4):547-552

Serum samples from 1028 sheep were collected from 32 herds within Federal District, in the central region of Brazil. The samples were examined by indirect fluorescent antibody test (IFAT) using sera diluted 1:64 and 1:50 as cut-off values for the detection of antibodies against Toxoplasma gondii and Neospora caninum, respectively. The observed prevalence for T. gondii infection was 38.22% (26.81%<CI 0.95<49.62%), and the titers ranged from 64 to 65536. The observed prevalence for N. caninum infection was 8.81% (7.08%<CI 0.95<10.53%). The titers ranged from 50 to 51200. The reactant sera to both pathogens corresponded to 4.67% of the samples. The risk factors were not determined because of the absence of negative herds for T. gondii and the high proportion of positive herds for N. caninum (87.50%). The prevalence for T. gondii infection was significantly higher among males than in females. The present work is the first report on seroprevalence of T. gondii and N. caninum in sheep from Federal District and shows that infection by both parasites is widespread in the ovine population from this region.  相似文献   

Performance of Farfantepenaeus paulensis (Pérez-Farfante, 1967) broodstock in tanks with sand and hard substrate     

Cintia L Nakayama  Silvio Peixoto  Adalto Bianchini  Ricardo B Robaldo  & Ronaldo O Cavalli 《Aquaculture Research》2008,39(4):398-405

This study evaluated the reproductive performance, physical condition and tissue biochemical composition of wild‐caught Farfantepenaeus paulensis kept for 50 days in maturation tanks provided with sand or hard substrate. The use of sand in F. paulensis maturation tanks had limited impact on the performance and biochemical composition of broodstock. Females in the hard‐bottom tank produced more spawns and more eggs in total, but those kept in the presence of the sand substrate produced a larger number of nauplii because an improvement in mating success was observed. An increased survival of females was also related to the presence of the sand substrate, which agrees with improvements in water quality and the physical condition of females. On the other hand, sourcing mature females was more difficult and time consuming in sand‐bottom tanks. The decision on whether or not to use sand substrates in F. paulensis maturation tanks must take into account not only productivity and animal welfare but also considers ease of operation and costs. These findings may have implications for the design of maturation systems for closed thelycum species.  相似文献   

Influence of steam-treated grass clippings on grass growth, drainage water quality and soil microbial properties in a simulated golf course     

Silvio Yoshiharu USHIWATA  Hiromi SASA  Kazuyuki INUBUSHI 《Soil Science and Plant Nutrition》2007,53(4):489-498

  相似文献   

Influence of Plant Residues after Steam-Treatment with High Temperature and Pressure on Soil Microbial Biomass C and N, Water-Soluble C and N, and pH   总被引：3，自引：0，他引：3  

Silvio Yoshiharu Ushiwata  Kazuyuki Inubushi 《Soil Science and Plant Nutrition》2005,51(5):775-777

Steam-treated grass trimmings (GrT), and wooden chips of pine (PnT) and walnut branches (WnT) or non-treated grass trimmings (GrNoT) and wooden chips of pine (PnNoT) and walnut branches (WnNoT) were mixed with soil (S) and then incubated for 10 weeks to measure microbial biomass C (MBC) and N (MBN), water-soluble C (WSC) and N (WSN), and soil pH. The results showed that there were a larger amount of MBC and WSC in steam-treated samples, principally in early period. It was probably due to the steam-treatment facilitating solubilization of organic C that served with substrate for microbial biomass. In grass trimming, the MBN and WSN had differences between treated and non-treated. No such differences in wooden chips was probably because the low total N content in these plants. The higher value of WSN showed in S+GnNoT showed more potential of nitrate pollution. The steam-treatment did not influence on soil pH after 1 week of incubation.  相似文献   

Evaluation of bulk density of Albaqualf soil under different tillage systems using the volumetric ring and computerized tomography methods     

Alceu Pedrotti  Eloy Antonio Pauletto  Silvio Crestana  Francisco Sandro Rodrigues Holanda  Paulo Estevo Cruvinel  Carlos Manoel Pedro Vaz 《Soil & Tillage Research》2005,80(1-2):115-123

The volumetric ring and the computerized tomography (CT) techniques were applied to study soil bulk density, in order to understand the compaction of an Albaqualf soil (Planosol) of the Rio Grande do Sul State, Southern Brazil (latitude 31°52′00″S and Longitude 52°21′24″W). Among six different tillage systems and crop rotations the greatest soil bulk density was measured for the continuous irrigated rice crop system and the lowest for the no-tillage treatment under rye grass straw. The CT method enabled the measurement of bulk density variations in the soil profile and indicated critical zones not observed by the volumetric ring method that measures only the mean sample soil bulk densities. A meaningful correlation between soil bulk densities measured by both methods was found, although the CT method presented more reliable results in comparison to the volumetric ring method. A 3% variation in bulk density was observed due to method intrinsic errors, probably also correlated to different samples sizes.  相似文献   

Study of Pyrene Adsorption on Two Brazilian Soils     

Silvio C��sar Godinho Teixeira  Roberta Louren?o Ziolli  M?nica Regina da Costa Marques  Daniel Vidal P��rez 《Water, air, and soil pollution》2011,219(1-4):297-301

This study investigated pyrene adsorption on two contrasting Brazilian soils: a Kandiudult and a Vertisol. It was found that the time taken to reach thermodynamic equilibrium depended on the soil type. The curves for different pyrene-to-soil mass ratios for Vertisol soil showed significant differences. This is probably related to the presence of 2:1 clays that may increase the adsorption of pyrene due to the resulting interlamellar space. The adsorption of pyrene on the Kandiudult showed, in general, good agreement with the Langmuir isotherm. In the case of the Vertisol, there was good agreement with the linear isotherm. The kinetic model that best explains the adsorption in Kandiudult was the pseudo second-order model. For the Vertisol, the Morris Weber model best explains the behavior of pyrene.  相似文献   

Effect of Water Stress in Maize Crop Production and Nitrogen Fertilizer Fate     

Helena Rimski-Korsakov  Gerardo Rubio  Raúl Silvio Lavado 《Journal of plant nutrition》2013,36(4):565-578

ABSTRACT

Maize production is affected by water and nitrogen (N) deficit either separately or joined, but this fact is not completely defined. The aim was to evaluate the fate of N in maize fertilized and subjected to water stress in controlled conditions. A greenhouse experiment was carried out at the University of Buenos Aires campus. The design was a 2 × 2 factorial with four replications. The factors were N: 70 and 140 kg N ha^?1 as labeled urea (¹⁵N), and water: 100% or 50% of the potential evapotranspiration. The harvest of aerial and root biomass was carried out at R1 stage. Nitrogen in plants, soils nitrate, ammonia volatilization, and ¹⁵N percentage were determined. Obtained results only partially agree with previous research. Water stress depressed aerial biomass production independently of N doses. When water was limiting, the uptake of N from fertilizer was independent of N. When water was not limiting, N uptake increased with the higher N doses. Volatilization losses were 3.7 to 7.8% of N applied as fertilizer. Plant N recovers was around 45% of the N applied, except in treatment water stressed with high N rate (19%). Nitrate-N from the fertilizer in the soil at harvest and accumulated N from the fertilizer in plant were lineally related (r² = 0.54; p < 0.001). Important destinations of N were accumulation in plant, volatilization and incorporation into soil organic matter. However, residual nitrate was a main fate in heavily fertilized and water deficit treatment. This process could lead to the eventual nitrate leaching.  相似文献