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1.
Plant Cell Environ ; 45(3): 823-836, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34806183

RESUMO

Deep rooting winter wheat genotypes can reduce nitrate leaching losses and increase N uptake. We aimed to investigate which deep root traits are correlated to deep N uptake and to estimate genetic variation in root traits and deep 15 N tracer uptake. In 2 years, winter wheat genotypes were grown in RadiMax, a semifield root-screening facility. Minirhizotron root imaging was performed three times during the main growing season. At anthesis, 15 N was injected via subsurface drip irrigation at 1.8 m depth. Mature ears from above the injection area were analysed for 15 N content. From minirhizotron image-based root length data, 82 traits were constructed, describing root depth, density, distribution and growth aspects. Their ability to predict 15 N uptake was analysed with the least absolute shrinkage and selection operator (LASSO) regression. Root traits predicted 24% and 14% of tracer uptake variation in 2 years. Both root traits and genotype showed significant effects on tracer uptake. In 2018, genotype and the three LASSO-selected root traits predicted 41% of the variation in tracer uptake, in 2019 genotype and one root trait predicted 48%. In both years, one root trait significantly mediated the genotype effect on tracer uptake. Deep root traits from minirhizotron images can predict deep N uptake, indicating the potential to breed deep-N-uptake-genotypes.


Assuntos
Nitratos , Raízes de Plantas , Genótipo , Fenótipo , Raízes de Plantas/genética , Triticum/genética
2.
Ther Adv Vaccines Immunother ; 8: 2515135520925336, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32518891

RESUMO

This study was a phase III, multicenter, double-blind, randomized, placebo-controlled trial to evaluate the safety and immunogenicity of a seasonal trivalent split, inactivated influenza vaccine (TIV) in healthy Serbian adults between the ages of 18 and 65 years. This egg-based vaccine was manufactured by the Institute of Virology, Vaccines and Sera, Torlak, Belgrade, Serbia. A total of 480 participants were assigned randomly in a ratio of 2:1 to receive a single intramuscular dose (0.5 ml) of the vaccine (15 µg of hemagglutinin per strain) or placebo (phosphate-buffered saline). Participants were monitored for safety, including solicited and unsolicited adverse events (AEs) and serious adverse events (SAEs). No SAEs related to vaccination were reported. Injection site pain (51.3%), injection site tenderness (40.4%), tiredness (17.0%), and headache (15.1%) were the most commonly reported solicited events in the vaccine group. Incidence of related unsolicited AEs was low (1.3%) among vaccinees. Hemagglutinin inhibition (HAI) titers were measured before and 21 days after vaccination in 151 participants. Overall, HAI seroconversion rates to H1 and H3 were observed in 90.1% and 76.2% of vaccinees, respectively. For B antigen, it was 51.5%, likely due to high pre-vaccination titers. Post-vaccination seroprotection rates were in the range of 78.2-95.0% for the three antigens. Post-vaccination geometric mean titers (GMT) were at least 3.8 times higher than baseline levels for all the three strains among vaccinees. Overall, the study showed that the vaccine was safe and well tolerated, and induced a robust immune response against all three vaccine strains. ClinicalTrials.gov identifier: NCT02935192, October 17, 2016.

3.
J Environ Manage ; 250: 109404, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31521037

RESUMO

The present study investigates the influence of the solid-liquid pretreatment of anaerobically digested slurry on the subsequent ultrafiltration of the obtained liquid fractions in a semi-commercial ultrafiltration pilot plant. The first pretreatment considered is based on centrifugation alone, the second one, is based on a combined flocculation-coagulation and centrifugation step. It was found that during ultrafiltration of the liquid fractions from both pretreatments, the cross-flow velocity had a larger influence on permeate flux than the applied pressure, suggesting the predominance of a gel-like fouling layer. Chemical rejections during ultrafiltration of the liquid fractions were higher than 96.9% for Cu, Zn, Fe, Ca, Mg and Al, without significant differences between the pretreatments. Finally, membrane inspection using SEM showed that the membrane fouling morphology was closely related to the feed pretreatment. Additionally, elemental membrane surface analysis with EDX revealed that alkaline and acidic cleaning was effective in removing most of the inorganic foulants accumulated on the membrane surfaces. However, after chemical cleaning, ultrafiltration membranes processing liquid fractions from centrifugation assisted with flocculation-coagulation restored the membrane pristine surface characteristics to a higher extend. This suggests that obtaining digestate liquid fractions by centrifugation assisted with flocculation-coagulation could have a positive impact on the long-term stability of the subsequent ultrafiltration step.


Assuntos
Metais Pesados , Purificação da Água , Floculação , Membranas Artificiais , Ultrafiltração
4.
Biologicals ; 52: 18-24, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29426673

RESUMO

The study explored influence of biological sex on development of humoral immune response to seasonal trivalent whole inactivated virus (WIV) and split virus (SV) influenza vaccines in outbred Swiss mouse model. To this end, mice of both sexes were immunized with WIV (WIV mice) and SV vaccines (SV mice) and examined for specific antibody response. Irrespective of sex, total IgG and neutralizing antibody responses to distinct virus strains were weaker in SV than in WIV mice. In WIV mice of both sexes, irrespective of strain specificity, IgG isotype response was dominated by IgG2a antibodies, while in SV mice nearly equal representation of IgG2a and IgG1 antibodies was found. The analyses of sex differences showed higher titers of H1N1-specific and both H1N1- and H3N2-specific total IgG and neutralizing antibodies in female WIV and SV mice, respectively. Additionally, sexual dimorphism in IgG subclass profile depended on vaccine type. Specifically, compared with males, in females WIV shifted IgG2a/IgG1 antibody ratio towards IgG2a isotype on the account of weaker IgG1 response, whereas in SV mice, irrespective of virus strain, IgG2a and IgG1 isotypes were equally represented in both sexes. These findings indicate the vaccine type-dependent sex bias in antibody response to inactivated influenza vaccines.


Assuntos
Anticorpos Antivirais/imunologia , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina G/imunologia , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/farmacologia , Caracteres Sexuais , Animais , Feminino , Vacinas contra Influenza/imunologia , Masculino , Camundongos
5.
Environ Technol ; 37(15): 1906-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26695081

RESUMO

Pig slurry, rich in plant nutrients such as nitrogen (N) and phosphorus (P), is generally applied to soil as organic fertilizer. However, costs related to slurry transport may limit its utilization to fields close to the farm, leading to significant N losses, namely ammonia (NH3) emissions. Slurry acidification, to minimize NH3 emissions, is a potential solution to this problem, while solid-liquid separation leads to a solid fraction (SF) - rich in organic matter (OM) and phosphorus - and a liquid fraction (LF) rich in soluble nutrients. We hypothesized that a combination of acidification and separation could affect the quality of the resulting fractions depending on the separation technique used. After acidification, the two most common techniques for separation, centrifugation (CF) and screw-press (SP), were applied. The main characteristics of the slurry fractions in terms of nutrient concentrations and speciation as well as the potential N mineralization (PNM) were analysed. Our results show SFs with improved properties, mostly N and PNM when acidification is performed before separation with both techniques. The PNM was significantly increased in LFs from both techniques after acidification. The [Formula: see text] concentration increased in LFs from SP with acidification; therefore, slurry acidification is recommended to avoid any N losses during the separation process with SP, while CF may not require such pretreatment. Acidification could allow the use of a cheaper technique such as SP relative to CF since it prevents NH3 emissions during the separation process and leads to more equilibrated fractions in terms of nutrient composition.


Assuntos
Agricultura/métodos , Amônia/análise , Esterco/análise , Eliminação de Resíduos Líquidos/métodos , Ácidos , Animais , Concentração de Íons de Hidrogênio , Nitrogênio/análise , Fósforo/análise , Suínos
6.
Parasitology ; 140(3): 378-84, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23127297

RESUMO

Separation of pig slurry into solid and liquid fractions is gaining importance as a way to manage increasing volumes of slurry. In contrast to solid manure and slurry, little is known about pathogen survival in separated liquid slurry. The viability of Ascaris suum eggs, a conservative indicator of fecal pollution, and its association with ammonia was investigated in separated liquid slurry in comparison with raw slurry. For this purpose nylon bags with 6000 eggs each were placed in 1 litre bottles containing one of the two fractions for 308 days at 5 °C or 25 °C. Initial analysis of helminth eggs in the separated liquid slurry revealed 47 Ascaris eggs per gramme. At 25 °C, egg viability declined to zero with a similar trend in both raw slurry and the separated liquid slurry by day 308, a time when at 5 °C 88% and 42% of the eggs were still viable in separated liquid slurry and raw slurry, respectively. The poorer survival at 25 °C was correlated with high ammonia contents in the range of 7.9-22.4 mM in raw slurry and 7.3-23.2 mM in liquid slurry compared to 3.2-9.5 mM in raw slurry and 2.6-9.5 mM in liquid slurry stored at 5 °C. The study demonstrates that at 5 °C, A. suum eggs have a higher viability in separated liquid slurry as compared to raw slurry. The hygiene aspect of this needs to be further investigated when separated liquid slurry is used to fertilize pastures or crops.


Assuntos
Ascaris suum/crescimento & desenvolvimento , Ovos/análise , Esterco/parasitologia , Amônia/análise , Animais , Concentração de Íons de Hidrogênio , Esterco/análise , Viabilidade Microbiana , Contagem de Ovos de Parasitas , Suínos , Temperatura , Eliminação de Resíduos Líquidos/métodos
7.
Environ Technol ; 33(16-18): 2119-31, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23240207

RESUMO

Pig slurry separation is a slurry treatment technique that can reduce excess loads of P, Cu and Zn to the arable land. This study investigated the effects of different commercial and laboratory separation treatments for pig slurry on P, Cu and Zn distribution into solid and liquid fractions. Solid and liquid separation fractions were collected from two commercial separators installed on the farm. Five different separation treatments were performed (polymer flocculation and drainage; coagulation with iron sulphate addition and polymer flocculation and drainage; ozonation and centrifugation; centrifugation only; and natural sedimentation) on sow and suckling piglet raw slurry. Particle size fractionation was performed on raw slurry and all separation fractions by sequential wet sieving and P, Cu and Zn concentrations were then measured in the particle size classes. Dry matter and total P, Cu and Zn were separated with higher efficiency when chemical pretreatments with flocculants and coagulants were introduced before mechanical separation at both commercial and laboratory scale. When solid fractions are utilized as crop fertilizer (primarily as P fertilizer), the loads of Cu and Zn to the soils are not markedly different than the loads applied with raw slurry. When liquid fractions are used as crop fertilizer (primarily as N fertilizer), the loads of Cu and Zn are markedly lower than those supplied with raw slurry. The loads of Cu and Zn introduced to the soil were lowest on application of the liquid fraction produced by optimized separation treatments that included flocculation and coagulation.


Assuntos
Cobre/análise , Esterco/análise , Fósforo/análise , Gerenciamento de Resíduos , Zinco/análise , Animais , Tamanho da Partícula , Suínos
8.
Water Res ; 46(12): 3849-58, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22591817

RESUMO

Chemical-mechanical separation of pig slurry into a solid fraction rich in dry matter, P, Cu and Zn and a liquid fraction rich in inorganic N but poor in dry matter may allow farmers to manage surplus slurry by exporting the solid fraction to regions with no nutrient surplus. Pig slurry can be applied to arable land only in certain periods during the year, so it is commonly stored prior to field application. This study investigated the effect of storage duration and temperature on chemical characteristics and P, Cu and Zn distribution between particle size classes of raw slurry and its liquid separation fraction. Dry matter, VFA, total N and ammonium content of both slurry products decreased during storage and were affected by temperature, showing higher losses at higher storage temperatures. In both products, total P, Cu and Zn concentrations were not significantly affected by storage duration or temperature. Particle size distribution was affected by slurry separation, storage duration and temperature. In raw slurry, particles larger than 1 mm decreased, whereas particles 250 µm-1 mm increased. The liquid fraction produced was free of particles >500 µm, with the highest proportions of P, Cu and Zn in the smallest particle size class (<25 µm). The proportion of particles <25 µm increased when the liquid fraction was stored at 5 °C, but decreased at 25 °C. Regardless of temperature, distribution of P, Cu and Zn over particle size classes followed a similar pattern to dry matter.


Assuntos
Amônia/química , Carbono/química , Cobre/química , Fósforo/química , Temperatura , Eliminação de Resíduos Líquidos/métodos , Zinco/química , Animais , Tamanho da Partícula , Sus scrofa
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