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151.
Marcela dos Santos Castro Maridelzira Betania Moraes David Evonnildo Costa Gonalves Andrei Santos Siqueira Rodrigo Rodrigues Virgulino Delia Cristina Figueira Aguiar 《Journal of veterinary science (Suw?n-si, Korea)》2022,23(2)
BackgroundCanine herpesvirus type 1 (CaHV-1) infects dogs and is associated with neonatal deaths and reproductive, ocular, neurological, and respiratory problems. In Brazil, reports of CaHV-1 have been restricted to the southeast and south regions, particularly in municipalities in the state of Rio Grande do Sul.ObjectivesTo assess the presence and variability of CaHV-1 in canine populations in the state of Pará, North Brazil.MethodsBiological samples from 159 dogs from 4 municipalities in the State of Pará were evaluated using polymerase chain reaction and phylogenetic analyses, with the target being the viral enzyme, thymidine kinase.ResultsCaHV-1 was detected in 13 dogs (8.2%), with 2 animals being from the municipality of Santa Bárbara do Pará, 8 from Algodoal Island, 2 from Salinópolis, and one from Capanema. The study sequences revealed 100% identity among themselves and 64% to 100% identity with the other nucleotide sequences from Australia, Brazil, United Kingdom, and United States, including 100% identity with the 2002 isolate from Australia. The 1996 isolate from France was grouped in a branch that was different from the sequence of this study.ConclusionsThis study presents the first molecular detection of CaHV-1 in dogs from the Amazon region in northern Brazil. The nucleotide identity between the strains and cytosine insertion in the sequences isolated in this study suggests at least 2 strains of CaHV-1 circulating in Brazil (Pará and BTU-1). 相似文献
152.
Srgio H. G. SILVA David C. WEINDORF Wilson M. FARIA Leandro C. PINTO Michele D. MENEZES Luiz R. G. GUILHERME Nilton CURI 《土壤圈》2021,31(4):615-626
Portable X-ray fluorescence (pXRF) spectrometry and magnetic susceptibility (MS) via magnetometer have been increasingly used with terrain variables for digital soil mapping. However, this methodology is still emerging in many countries with tropical soils. The objective of this study was to use proximal soil sensor data associated with terrain variables at varying spatial resolutions to predict soil classes using the Random Forest (RF) algorithm. The study was conducted on a 316-ha area featuring highly variable soil classes and complex soil-landscape relationships in Minas Gerais State, Brazil. The overall accuracy and Kappa index were evaluated using soils that were classified at 118 sites, with 90 being used for modeling and 28 for validation. Digital elevation models (DEMs) were created at 5-, 10-, 20-, and 30-m resolutions using contour lines from two sources. The resulting DEMs were processed to generate 12 terrain variables. Total Fe, Ti, and SiO2 contents were obtained using pXRF, with MS determined via a magnetometer. Soil class prediction was performed using the RF algorithm. The quality of the soil maps improved when using only the five most important covariates and combining proximal sensor data with terrain variables at different spatial resolutions. The finest spatial resolution did not always provide the most accurate maps. The high soil complexity in the area prevented highly accurate predictions. The most important variables influencing the soil mapping were MS, Fe, and Ti. Proximal sensor data associated with terrain information were successfully used to map Brazilian soils at variable spatial resolutions. 相似文献
153.
PCB removal,soil enzyme activities,and microbial community structures during the phytoremediation by alfalfa in field soils 总被引:1,自引:1,他引:1
Chen Tu Ying Teng Yongming Luo Xianghui Sun Shaopo Deng Zhengao Li Wuxing Liu Zhihong Xu 《Journal of Soils and Sediments》2011,11(4):649-656
Purpose
An in situ phytoremediation trial was developed in order to investigate the function of alfalfa during a 2-year bioremediation of an agricultural soil contaminated with polychlorinated biphenyls (PCBs). The study was conducted with the aim to better understand the application potential of PCB phytoremediation at field scale. 相似文献154.
Jana Rydlová David Püschel Radka Sudová Milan Gryndler Olga Mikanová Miroslav Vosátka 《植物养料与土壤学杂志》2011,174(1):128-134
This study focused on the application of native strains of arbuscular mycorrhizal fungi (AMF) and Sinorhizobium in effective crop production during reclamation of coal‐mine spoil banks. Two greenhouse experiments were conducted in spoil‐bank clay with a low dose of organic amendment to determine whether the microbial inoculation improves growth and utility qualities of two cultivars of Linum usitatissimum L. (oil and fiber flax). Inoculation with two native AMF isolates (Glomus mosseae, G. intraradices, and their mixture) significantly increased growth and shoot phosphorus (P) concentration of both flax cultivars. Inoculated fiber flax plants produced fivefold more fibers than the uninoculated ones. In oil flax, mycorrhizal inoculation significantly but quantitatively to a minor degree decreased the concentration of nonsaturated fatty acids in the seed oil. A mixture of five native Sinorhizobium sp. strains supported growth and P uptake of oil flax only in the absence of AMF. However, these beneficial effects of the bacteria were significantly lower as compared to AMF. No synergic action of Sinorhizobium strains and AMF was observed, and their interactions were often even antagonistic. Inoculation with AMF significantly decreased population density of Sinorhizobium in the soil. These results suggest that a careful selection of suitable bacterial strains is necessary to provide effective AMF combinations and maximize flax‐growth support. 相似文献
155.
Katriina Kyllönen Hannele Hakola Heidi Hellén Markku Korhonen Matti Verta 《Water, air, and soil pollution》2012,223(3):1171-1182
Total gaseous mercury (TGM) fluxes from the forest floor and a boreal wetland were measured by a flux chamber technique coupled
with an automatic mercury vapour analyser. The fluxes were measured at three sampling sites in southern Finland, 61°14′ N,
25°04′ E in summer 2007, with additionally in situ TGM concentrations in the air at one of the sites and mercury bulk deposition
at another. Most of the flux data were collected during the daytime. At one of the sites, diurnal flux behaviour was studied,
and a clear cycle with an afternoon maximum and a night minimum was observed. The highest emissions (up to 3.5 ng m−2 h−1) were observed at the forest floor site having a moss and grass cover. At the wetland and litter-rich forest floor sites,
the emissions were below 1 ng m−2 h−1 and sometimes negative (down to −1.0 ng m−2 h−1), indicating mercury uptake. The measured average fluxes in August were 0.9 ± 1.1 and 0.2 ± 0.3 ng m−2 h−1 for the forest floor sites and wetland sites, respectively. The flux data were compared with the mercury bulk deposition,
which proved to be of the same magnitude, but opposite in sign. At the mossy forest floor site, the extrapolated TGM emissions
were 130% of the Hg deposition in August 2007. Comparison with other studies showed that the fluxes in background areas are
relatively uniform, regardless of measurement site location and method used. Airborne TGM remained at the background level
during the study, with an average value of 1.3 ± 0.2 ng m−3; it frequently showed a diurnal cycle pattern. 相似文献
156.
Kai Wang Zhiqiang Zhu Huagang Huang Tingqiang Li Zhenli He Xiaoe Yang Ashok Alva 《Journal of Soils and Sediments》2012,12(4):556-564
Purpose
Soil contamination by multiple organic and inorganic contaminants is common but its remediation by hyperaccumulator plants is rarely reported. The growth of a cadmium (Cd) hyperaccumulator Sedum alfredii and removal of contaminants from Cd and polycyclic aromatic hydrocarbons (PAHs) co-contaminated soil were reported in this study. 相似文献157.
Soon-An Ong Li-Ngee Ho Yee-Shian Wong Komalathevi Raman 《Water, air, and soil pollution》2012,223(4):1615-1623
Combinations of sequential anaerobic and aerobic process enhance the treatment of textile wastewater. The aim of this study
was to investigate the treatment of diazo dye Reactive Black 5 (RB5)-containing wastewater using granular activated carbon
(GAC)–biofilm sequencing batch reactor (SBR) as an integration of aerobic and anaerobic process in a single reactor. The GAC–biofilm
SBR system demonstrated higher removal of COD, RB5 and aromatic amines. It was observed that the RB5 removal efficiency improved
as the concentration of co-substrate in the influent increased. The alternative aeration introduced into the bioreactor enhanced
mineralization of aromatic amines. Degradation of RB5 and co-substrate followed second-order kinetic and the constant (k
2) values for COD and RB5 decreased from 0.002 to 0.001 and 0.004 to 0.001 l/mg h, respectively, as the RB5 concentration increased
from 100 to 200 mg/l in the GAC–biofilm SBR system. 相似文献
158.
Adding supplements to hen feed can increase egg nutritional value. Astaxanthin, tocotrienols, and tocopherols are potent antioxidants that provide health benefits to humans. We hypothesized that the addition of these nutrients to hen feed would result in an increased nutrient content in egg yolk with minimum changes in functional properties. Laying hens (Hy-Line W-36 breed) were fed four diets with different supplementation levels of palm toco concentrate and algae biomass containing astaxanthin for 8 weeks. Egg yolks were analyzed for physical, chemical, and functional properties. The feed with the highest nutrient concentration was also studied for stability of these antioxidants using the Arrhenius approach. No significant differences were observed in functional properties except for emulsification capacity and sensory characteristics among eggs from different diet treatments. Changes in egg yolk color reached the maximum values at day 8. Incorporation of tocopherols and tocotrienols increased until day 8, astaxanthin incorporation increased until day 10, and all decreased thereafter. Feed nutrients resulted in a dose-response relationship of these compounds in the egg yolk. The transfer efficiency ranged from 0 to 9.9% for tocotrienols and tocopherols and from 7.6 to 14.9% for astaxanthin at their peak values. Results of the Arrhenius accelerated stability study showed significant differences in the shelf life of various nutrients, and these results can be used to properly formulate and store the feed materials. 相似文献
159.
Yaying Li Juan Wang Fuxiao Pan Stephen James Chapman Huaiying Yao 《Journal of Soils and Sediments》2016,16(5):1472-1480
Purpose
Soil microorganisms are important in the cycling of plant nutrients. Soil microbial biomass, community structure, and activity are mainly affected by carbon substrate and nutrient availability. The objective was to test if both the overall soil microbial community structure and the community-utilizing plant-derived carbon entering the soil as rhizodeposition were affected by soil carbon (C) and nitrogen (N) availability.Materials and methods
A 13C-CO2 steady-state labeling experiment was conducted in a ryegrass system. Four soil treatments were established: control, amendment with carboxymethyl cellulose (CMC), amendment with ammonium nitrate (NF), combined CMC and NF. Soil phospholipid fatty acid (PLFA) and 13C labeling PLFA were extracted and detected by isotope ratio mass spectrometer.Results and discussion
The combined CMC and NF treatment with appropriate C/N ratio (20) significantly enhanced soil microbial biomass C and N, but resulted in lower soil inorganic N concentrations. There was no significant difference in soil PLFA profile pattern between different treatments. In contrast, most of the 13C was distributed into PLFAs 18:2ω6,9c, 18:1ω7c, and 18:1ω9c, indicative of fungi and gram-negative bacteria. The inorganic-only treatment was distinct in 13C PLFA pattern from the other treatments in the first period of labeling. Factor loadings of individual PLFAs confirmed that gram-positive bacteria had relatively greater plant-derived C contents in the inorganic-only treatment, but fungi were more enriched in the other treatments.Conclusions
Amendments with CMC can improve N transformation processes, and the ryegrass rhizodeposition carbon flux into the soil microbial community is strongly modified by soil N availability.160.
Yong Wang Shuqing Gao Cuilan Li Jinjing Zhang Lichun Wang 《Journal of Soils and Sediments》2016,16(7):1849-1857