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Spada E Proverbio D della Pepa A Perego R Baggiani L DeGiorgi GB Domenichini G Ferro E Cremonesi F 《Journal of Feline Medicine and Surgery》2012,14(6):369-377
Stray cat colonies in urban and rural areas of Lombardy, northern Italy, were surveyed for seroprevalence of feline immunodeficiency virus (FIV) antibodies, feline leukaemia virus (FeLV) antigen and Toxoplasma gondii IgG. Of 316 cats tested, 6.6% were positive for FIV and 3.8% were positive for FeLV infection; 203 cats were tested for T gondii IgG antibodies and a prevalence of 30.5% was detected. Statistical analysis tested the influence of provenience, age, gender, health status and laboratory results on seroprevalence and found male gender and adult age were risk factors for FIV infection. FIV-infected cats were more likely to have a decreased red blood cell count than FIV seronegative cats. No predictors were significantly associated with FeLV and T gondii seropositivity. Colony cats in this study posed a limited risk for retrovirus infection to pet cats allowed outdoors, whereas toxoplasmosis exposure was comparable with the worldwide data. 相似文献
64.
Daniella Araujo Vasconcelos de Oliveira Wander Gustavo Botero Josué Carinhanha Caldas Santos Ricardo Moutinho da Silva Leonardo Machado Pitombo Janaina Braga do Carmo Luana Maria Tavares Rosa Luciana Camargo de Oliveira 《Water, air, and soil pollution》2017,228(7):265
The increase in demand for food due to the rapid population growth in recent years has raised the use of fertilizers, particularly phosphate salts. This fact has contributed to the excess amount of phosphorus species in aquatic systems. This is due to the leaching of these species present in the fertilizers applied to the soil to aquatic environments and may lead to eutrophication in these environments. Substances capable of interacting with the phosphate in the aquatic environment are promising for the reduction on the environmental impact. The humin, an insoluble fraction of humic material, has potential for phosphate retention, behaving like a chelating resin. Thus, the purpose of this research was to study the interaction between humin and phosphate. The equilibrium time between humin and phosphate was 15 min, where hydrogenionic potential (pH) 4.0 was the most effective in the interaction process. In this pH, the humin retained 33% of phosphate added. The complexing capacity of the humin-phosphate system was 11.53 mg g?1. The adsorption studies indicated that the system follows a kinetic pseudo-second-order model. The Freundlich model was the most suitable to describe the phosphate adsorption process in humin. To evaluate the humin application in real systems, humin was added to the domestic wastewater. Sixteen percent of the total phosphate was adsorbed by the humin. Based on these results, humin has the potential to phosphate retention in domestic wastewater and could be used as a chelating resin minimizing environmental impact. 相似文献
65.
Shenia Oliveira Souza Marina de Magalhães Silva Josué Carinhanha Caldas Santos Luciana Camargo de Oliveira Janaina Braga do Carmo Wander Gustavo Botero 《Journal of Soils and Sediments》2016,16(6):1764-1775
Purpose
Due to the modernization of the agro-industrial sector, compounds with different toxicity and effects on human health and animal have been used and consequently affecting the environment. Among them, tetracycline (TC) stands out as one of the antibiotics most commonly used worldwide. This study evaluated the TC interaction with different fractions of peat in natura and humic substances, humic acid, fulvic acid, and humin.Materials and methods
The different fractions of the organic matter were characterized by organic matter content, elemental analysis, spectroscopic analysis (E4/E6), and nuclear magnetic resonance of carbon 13 (NMR 13C), and the interaction between TC and different fractions of organic matter was made by fluorescence spectrometry. We used the tangential ultra-filtration system for determining the complexation capability of humic substances (HSs), fulvic acids (FA), humic acids (HA), and humin (HUM) from peat with TC. Finally, we evaluated sorption kinetic experiments between TC and peat in natura.Results and discussion
The peat samples, humic substances, FAs, HAs, and HUM were characterized by organic matter (OM), atomic ratio (H/C and C/O) calculated from elemental analysis data, functional groups quantified by NMR 13C data, and E4/E6 ratio, and the results show significant differences in the structural characteristics of the fractions of OM influenced by the type of microorganisms and environmental factors associated with this decomposition. Data analysis revealed the strongest interaction between HUM and TC (59.19 mg g?1), followed by interaction between HS and TC (43.36 mg g?1 HS). In the sorption studies, these conditions showed the best model to describe the system under consideration using the Freundlich model.Conclusions
The results showed that the different fractions of the OM extracted from peat show different contributions that affect the bioavailability of contaminants to the environment.66.
Ariadna Valentina Lopes Luciana Coe Girão Carlos A. Peres 《Biological conservation》2009,142(6):1154-1997
Habitat loss and fragmentation promote relatively predicable shifts in the functional signature of tropical forest tree assemblages, but the full extent of cascading effects to biodiversity persistence remains poorly understood. Here we test the hypotheses that habitat fragmentation (a) alters the relative contribution of tree species exhibiting different reproductive traits; (b) reduces the diversity of pollination systems; and (c) facilitates the functional convergence of reproductive traits between edge-affected and early-secondary forest habitats (5-32 years old). This study was carried out in a severely fragmented 670-km2 forest landscape of the Atlantic forest of northeastern Brazil. We assigned 35 categories of reproductive traits to 3552 trees (DBH ? 10 cm) belonging to 179 species, which described their pollination system, floral biology, and sexual system. Trait abundance was calculated for 55 plots of 0.1 ha across four habitats: forest edges, small forest fragments (3.4-83.6 ha), second-growth patches, and core tracts of forest interior within the largest available primary forest fragment (3500 ha) in the region. Edge-affected and secondary habitats showed a species-poor assemblage of trees exhibiting particular pollination systems, a reduced diversity of pollination systems, a higher abundance of reproductive traits associated with pollination by generalist diurnal vectors, and an elevated abundance of hermaphroditic trees. As expected, the reproductive signature of tree assemblages in forest edges and small fragments (edge-affected habitats), which was very similar to that of early second-growth patches, was greatly affected by both habitat type and plot distance to the nearest forest edge. In hyper-fragmented Atlantic forest landscapes, we predict that narrow forest corridors and small fragments will become increasingly dominated by edge-affected habitats that can no longer retain the full complement of tree life-history diversity and its attendant mutualists. 相似文献
67.
Bruno B. Cunha Wander Gustavo Botero Luciana Camargo Oliveira Viviane M. Carlos Marcelo L. M. Pompêo Leonardo F. Fraceto André H. Rosa 《Water, air, and soil pollution》2012,223(1):329-336
The sorption of four endocrine disruptors, bisphenol A (BPA), estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2)
in tropical sediment samples was studied in batch mode under different conditions of pH, time, and sediment amount. Data obtained
from sorption experiments using the endocrine disruptors (EDs) and sediments containing different amounts of organic matter
showed that there was a greater interaction between the EDs and organic matter (OM) present in the sediment, particularly
at lower pH values. The pseudosecond order kinetics model successfully explained the interaction between the EDs and the sediment
samples. The theoretical and experimentally obtained q
e values were similar, and k values were smaller for higher SOM contents. The k
F values, obtained from the Freundlich isotherms, varied in the ranges 4.2–7.4 × 10−2 (higher OM sediment sample, S2) and 1.7 × 10−3–3.1 × 10−2 (lower OM sediment sample, S1), the latter case indicating an interaction with the sediment that increased in the order: EE2 > > E2 > E1 > BPA. These results
demonstrate that the availability of endocrine disruptors may be directly related to the presence of organic material in sediment
samples. Studies of this kind provide an important means of understanding the mobility, transport, and/or reactivity of this
type of emergent contaminant in aquatic systems. 相似文献
68.
Giupponi Luca Leoni Valeria Colombo Federico Cassani Elena Hejna Monika Rossi Luciana Pilu Roberto 《Genetic Resources and Crop Evolution》2021,68(5):2075-2091
Genetic Resources and Crop Evolution - The loss of agrobiodiversity is a topic of global impact. On a local scale, Lombardy, in the Alpine macro-Region, has lost more than 78% of its plant... 相似文献
69.
Bekris Fotios Georgescu Luciana Bariotakis Michael Kotzabasis Kiriakos Panopoulos Nickolas Pirintsos Stergios 《Journal of Soils and Sediments》2019,19(1):381-392
Journal of Soils and Sediments - Despite the important role of soil ammonia-oxidizing microorganisms (AOM) in the biogeochemical cycle of nitrogen, a unified view of the factors driving their... 相似文献
70.