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91.
Paolo Bruno Maurizio Caselli Gianluigi de Gennaro Lucia Scolletta Livia Trizio Maria Tutino 《Water, air, and soil pollution》2008,193(1-4):37-50
Volatile organic compounds (VOC) have been monitored in 12 sites of Canosa di Puglia, a city located in the Southern of Italy, in order to identify the main VOC source—vehicular traffic or industrial—and to evaluate the critical situations in the city. Monitoring, carried out by using Radiello® diffusive samplers, has been planned taking into account the traffic density and the architecture of the city. From the study of the data it has been emerged that, among all considered VOC, benzene, toluene, ethylbenzene and xylenes (BTEX) are the pollutants at higher concentration. However no critical situation has appared from the present monitoring. Maps of daily benzene and toluene concentrations have shown that the most significant pollution phenomena happens in the center of the urban area which is in a valley with narrow roads and high buildings that do not allow an efficient dispersion of pollutants. The study of the diagnostic ratios between the toluene and benzene concentrations in the several areas (average T/B?=?3.4) and the high Pearson’s coefficient among the pollutants, and in particular between benzene and toluene concentrations (r?=?0.9505), have suggested that in urban area these pollutants are emitted from the same source: the vehicular traffic. 相似文献
92.
Silva AF Rangel L Ortiz CG Morales E Zanella EL Castillo-Velázquez U Gutierrez CG 《Veterinary parasitology》2012,188(1-2):175-178
This study evaluated the presence of Neospora caninum in ovarian follicle aspirates and uterine flushes obtained from N. caninum seropositive dairy cows. Ninety-two cows that aborted within the previous 90 days were sampled to determine the presence of antibodies against N. caninum. Thirteen seropositive cows were chosen for collection of blood leukocytes, uterine flushes (UF; n=12) and follicular aspirates (OPU; n=13). Samples were centrifuged and the cellular sediment from the follicular fluid, uterine flushes and blood leukocytes were used for DNA extraction and PCR. Follicular aspirates had the highest frequency of DNA amplification for N. caninum (p<0.05, 92.3%; 12/13). Whereas uterine (4/12) and blood leukocyte (5/13) samples had similar (p>0.05) rate of positive results. Nonetheless, there was no agreement between blood leukocytes and follicular samples taken from the same animal (Cohen Kappa=-0.16). Similarly, blood leukocytes and uterine results had moderate agreement between them (Cohen Kappa=0.47). This study indicates that N. caninum is present in the ovarian follicle and uterus of seropositive cows, suggesting a possible risk of neosporosis transmission between females during oocyte and embryo collection and transfer. Hence, precautions should be taken to minimize the risk of N. caninum transmission. Furthermore, the high incidence of positive results in follicle samples, that exceeded that of their paired blood leukocytes, suggests a possible tropism of N. caninum for the ovarian follicle. 相似文献
93.
Mariarosaria Marinaro Anna Lucia Bellacicco Michele Camero Elvira Tarsitano Maria Tempesta Antonio Cassone Canio Buonavoglia 《Veterinary microbiology》2009,138(3-4):266-272
Enzyme-linked immunosorbent assays (ELISAs) were developed to detect caprine herpervirus-1 (CpHV-1)-specific IgG1 and IgG2 in sera from 43 naturally infected goats. The analysis of the IgG subclasses showed a dual pattern of distribution in seropositive goats with a major group of animals (36 out of 43) exhibiting significantly higher levels of IgG2 over IgG1 and a minor group (7 out of 43) possessing equal levels of IgG1 and IgG2. Four goats were experimentally infected with a virulent CpHV-1 Ba.1 strain by the intranasal or the intravaginal route and the kinetics of appearance of CpHV-1-specific IgG, IgG1 and IgG2 in the serum were studied. Two weeks following infection, both IgG1 and IgG2 levels increased although convalescent sera (i.e., collected 5–8 weeks post-infection) showed a clear prevalence of the IgG2 subclass. To determine the contribution of the different IgG subclasses to herpesvirus immunity, serum neutralization (SN) assays were performed in both naturally and experimentally infected goats. The kinetics of SN showed that neutralization activity was mainly associated to the IgG1 subclass and this was also confirmed in naturally infected goats. The results are discussed from the standpoint that the profile of the IgG subclasses is instrumental to study immune responses to CpHV-1 and that vaccination strategies may benefit from this information. 相似文献
94.
95.
Alexandre Lima NEPOMUCENO Renata FUGANTI-PAGLIARINI Maria Sueli Soares FELIPE Hugo Bruno Correa MOLINARI Edivaldo Domingues VELINI Eduardo Romano de Campos PINTO Maria Lucia Zaidan DAGLI Galdino ANDRADE FILHO Patr cia Machado Bueno FERNANDES 《农业科学与工程前沿(英文版)》2020,7(2):204-210
Globally, the area of land cultivated with genetically modified (GM) crops has increased a thousand-fold over the last two decades. Although this technology has become important for food production, the regulatory frameworks that underpin these outcomes are based on a list of requirements for a risk assessment that differ from country to country. In recent years, policymakers have had the opportunity to learn from the controversies over transgenics to create effective regulatory milestones for emerging technologies, allowing them to reach their potential for a more sustainable agriculture, ensuring food security. In Brazil, Law No. 11.105 of 24 March 2005 established a framework with four main organizations responsible for risk assessment and management. However, most of new breeding technologies did not exist at that time and were not considered in this law. In 2016, Normative Resolution No. 16 of the National Biosafety Technical Commission (CTNBio) was established to address this gap based on the evaluation of the products obtained through these techniques (termed Innovative Precision Improvement Techniques in the resolution), in a case-by-case consultation system. Briefly, if the product is designated to be a GM, the developer will have to go through the biosafety requirements and will be approved only after CTNBio risk assessment. If the product is designated not to be GM (for the purposes of the legislation), then it can be registered using the existing procedures. Currently, 152 GM products are commercially approved in Brazil. In 2018, CTNBio assessed the first consultation on commercial release of plants generated using the new breeding technologies and has subsequently approved six products. It is expected that many institutions would be able to participate in Brazilian and world markets, developing and introducing new biotechnological solutions and products through a more sustainable approach and without facing public disapproval, a common issue for GM crops. 相似文献
96.
The herbicide isoproturon was degraded rapidly in a sandy loam soil under laboratory conditions (incubation temperature, 15°C; soil moisture potential, -33 kPa). Degradation was inhibited following treatment of the soil with the antibiotic chloramphenicol, but unaffected by treatment with cycloheximide, thus indicating an involvement of soil bacteria. Rapid degradation was not observed with other phenylurea herbicides, such as diuron, linuron, monuron or metoxuron incubated in the same soil under the same experimental conditions. Three successive applications of isoproturon to ten soils differing in their physicochemical properties and previous cropping history induced rapid degradation of the herbicide in most of them under laboratory conditions. There were, however, no apparent differences in ease of induction of rapid degradation between soils which had been treated with isoproturon for the last five years in the field and those with no pre-treatment history. A mixed bacterial culture able to degrade isoproturon in liquid culture was isolated from a soil in which the herbicide degraded rapidly. 相似文献
97.
The access of amyloglucosidase to the carbohydrate molecule was taken as a measure of interactions occurring among starch, amylose, amylopectin, β-dextrin and purified gluten, gliadins, high molecular weight glutenin subunits, or bovine serum albumin when they were mixed together and gelatinized before digestion. The most relevant decrease in liberated glucose, denoting coverage of some reaction sites for amyloglucosidase, occurred when gliadins were mixed with the carbohydrates. Other proteins were not as effective as gliadins. Amylopectin was not affected by any protein. Comparison of results allows some hypothesis to be formulated about the influence of structure on molecular interactions. 相似文献
98.
Lucia Lioi Incoronata Galasso Maria Gloria Daminati Angela Rosa Piergiovanni 《Genetic Resources and Crop Evolution》2010,57(4):533-542
The primary structure of the double-headed Bowman-Birk inhibitor (BBI) family and the antitryptic activity were investigated
in cultivated and wild Phaseolus species. Two BBI types were identified; the first one inhibits trypsin and chymotrypsin (tc-BBI), the second one elastase
and trypsin (et-BBI). Only tc-BBI was found in P. lunatus and P. parvulus, while none of BBI types, identified in this study, was found in P.
leptostachyus. The deduced amino acid sequences revealed some polymorphisms within both tc-BBI and et-BBI binding loops that could affect
the inhibitory activity. The trypsin inhibitor content showed a high variation with the lowest value recorded in P. lepthostachyus and the highest one observed in P. oligospermus. Southern blot analysis confirmed the absence of both BBI types in P. leptostachyus and suggests that in P. coccineus, P. dumosus and P. costaricensis, the two genes were clustered in a narrow genomic region of 1.3 kbp. 相似文献
99.
Lucia Kořenková Martin Šebesta Martin Urík Marek Kolenčík Gabriela Kratošová Marek Bujdoš 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2017,67(4):285-291
Since the fate of nanoparticles after their release in the environment and their possible transfer in plants and subsequent impacts is still largely unknown, this paper evaluates the potential phytotoxic effects of up to 20% w/w TiO2 nanoparticles (nTiO2) on barley cultivated in hydroponics and agar media. The X-ray diffraction analysis confirmed that nTiO2 powder corresponds to anatase phase. On agar medium only high concentrations of nTiO2 (10% and 20% w/w) induced significant inhibition of shoot growth. However, hydroponics treatment with nTiO2 up to 1000?mg?L?1 did not show any adverse effect on the shoot growth. In both experiments, (i) root growth inhibition effects became visible with increasing concentration of nTiO2, (ii) plants treated with nTiO2 showed no change in chlorophyll a and b content, even though the plants absorbed nTiO2, (iii) weight of biomass treated with nTiO2 was not significantly different compared to control. Therefore, we assume that transport of nTiO2 into the aerial parts is limited due to the presence of effective mechanical or physiological barriers in roots. Overall, it appears that early root growth is a relevant indicator of potential effects of nTiO2 exposure. Our results also indicate that synthesized nTiO2 are not significantly toxic to the barley when applied at the concentrations used in this work, even though plants absorb titanium. 相似文献
100.
Summary Phaseolin seed protein was used as a marker to reveal the origin, Mesoamerican or Andean, of common bean (Phaseolus vulgaris) accessions cultivated in some countries (Korea, China, and Japan) of eastern Asia. Andean cultivars (T and C phaseolin patterns) are predominant in this geographical area. Introductions from Middle America, represented by cultivars with S phaseolin type, also occurred at lower rate. In all cases, genotypes with larger seeds have been favoured. 相似文献