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951.
Purpose
Carbon nanomaterials (CNMs) have attracted a great deal of research interest for their potential environmental applications because of their unique properties. Adsorption of organic chemicals on CNMs was reported to be important in controlling their environmental risks. However, the kinetics of the adsorption is hardly investigated in literature. The objective of this work was, therefore, to quantitatively describe the sorption kinetics of 17 α-ethinyl estradiol (EE2) and bisphenol A (BPA) on CNMs as compared to activated carbon (AC). 相似文献952.
Ruijuan Li Jinfeng Zhao Chuanfan Sun Wenjing Lu Chengjin Guo Kai Xiao 《Frontiers of Agriculture in China》2010,4(2):195-209
As a kind of enzyme widely existing in eukaryotic species, especially in grains and oil seeds, phytases play an important
role in the degradation of some phosphates containing organic molecules. So far, phytases derived from various species have
been successfully used as animal feed additives. It has also been experimentally verified that phytases have a potential use
in generating crop germplasm with high phosphorus use efficiency, based on their biochemical role in releasing Pi from the
phytate and its derivatives. In this paper, the biochemical properties, molecular characterizations, functions and the potential
application perspective of phytases are reviewed and commented on, aiming at the further exploration of the biochemical and
molecular characterizations, and promotion of the application of phytases, a kind of important enzyme possessing potential
use in animal feeding and creation of high P use crop cultivars, in the future. 相似文献
953.
I. Placha M. Pogany Simonova K. Cobanova A. Laukova S. Faix 《Research in veterinary science》2010,89(2):257-261
We investigated the effect of Enterococcus faecium on phagocytic activity, antioxidative status in vivo and the effect of E. faecium and 0.4% concentration of Thymus vulgaris essential oil (EO) on the duodenal tissue integrity in vitro in laying hens. The birds were fed the same standard diets and were divided into four groups. E. faecium was added to the drinking water for the second and fourth groups. EO was added to special chambers for measuring trans-epithelial electrical resistance (TEER) for the third and fourth groups only. TEER was lower in groups where EO was added, but in the group with E. faecium TEER was not changed significantly. Our results show that EO at 0.4% concentration may negatively affect intestine integrity, and the probiotic strain E. faecium AL41 is able to eliminate this effect and can strengthen non-specific immunity. To confirm our findings further histopathological investigations of intestinal tissue are needed. 相似文献
954.
G. Yu. Rabinovich Yu. I. Mitrofanov V. A. Kotelnikov D. V. Tikhomirova 《Russian Agricultural Sciences》2013,39(5-6):468-470
Microbiological testing (bioindication) of fallow lands of ameliorative objects in the humid zone has been carried out. It is shown that soils of plots with an unsatisfactory water and air regime are characterized by increased enzyme activity, high level of the redox ratio, and high content of labile humus and nutrient elements in a mobile form. On plots with a favorable water and air regime, activation of mineralization processes with no means for restoring fertility is also a negative factor. Such evaluation allows determining the necessary rehabilitation measures. 相似文献
955.
The probabilistic approach methodology that assesses the permissible level of heavy metal (HM) pollution of agricultural land according to sanitation and hygiene principle is developed. Application of the methodology is illustrated by using information from the database, which characterize parameters of zinc transition from the soil to agricultural plants. 相似文献
956.
A method to improve the air regime of soil by reducing its density and increasing its total porosity has been suggested. This method consists in adding organo-mineral compost, which is based on agricultural and industrial wastes, to the topsoil. 相似文献
957.
Joseph H. Anderson George R. Pess Peter M. Kiffney Todd R. Bennett Paul L. Faulds William I. Atlas Thomas P. Quinn 《Ecology of Freshwater Fish》2013,22(1):30-42
Anadromous fishes are frequently restricted by artificial barriers to movement such as dams and culverts, so measuring dispersal helps identify sites where improved connectivity could promote range expansion and population viability. We used a combination of DNA‐based parentage analysis and mark–recapture techniques to evaluate dispersal by juvenile coho salmon (Oncorhynchus kisutch) in a population in the initial stages of colonisation following installation of fish passage structures at a previously impassable dam on the Cedar River, WA, USA. The spatial distribution of individuals within maternal families revealed that dispersal was common. Among the offspring of radio‐tagged mothers, 28% were collected outside the spawning reach and dispersed up to 6.3 km (median = 1.5 km). Most juveniles captured in a tributary (Rock Creek, where few adults spawned) had immigrated from the Cedar River and represented many different families. Juvenile dispersal therefore provided a secondary phase of spatial expansion following initial colonisation by adults. Consistent with the condition‐dependent dispersal hypothesis, juveniles that dispersed farther upstream in the tributary were larger than fish collected near the tributary mouth. Overall, the results demonstrated widespread dispersal in a system with low coho salmon densities, and this might increase the rate of population growth if it reduces the effects of local density dependence. By implication, juveniles can take advantage of rearing habitats reconnected through barrier removal, even when such areas are located several kilometres from adult breeding grounds. 相似文献
958.
Large‐scale inoculation with arbuscular mycorrhizal fungi (AMF) is generally impractical in most regions and we have little understanding of the factors that determine inoculation success. Nevertheless, the ability to take full advantage of indigenous AMF for sustainable production needs to be developed within cropping systems. We used part of a long‐term field experiment to understand the influence of tillage and the preceding crop on AMF colonization over the growing season. Arbuscular mycorrhiza colonization rate was more affected by treatment (tillage or the combination of crop and preceding crop) than by the total number of AMF spores in the soil. Conventional tillage (CT) had a statistically significant negative effect (P ≤ 0.05) on spore numbers isolated from the soil, but only in the first year of study. However, the AMF colonization rate was significantly reduced by CT, and the roots of wheat, Triticum aestivum, L, cv. Coa after sunflower, Helianthus annuus L., were less well colonized than were those of triticale, X Triticosecale Wittmack, cv. Alter after wheat, but the affect of tillage was more pronounced than was the effect of crop combination. Under no‐till there was a significant increase in AMF colonization rate throughout the sampling period in both wheat and triticale, indicating that the extraradical mycelium previously produced acted as a source of inoculum. In general, triticale showed greater AMF colonization than wheat, despite the preceding crop being less mycotrophic. Under these experimental conditions, typical of Mediterranean agricultural systems, AMF colonization responded more strongly to tillage practices than to the combination of crop and preceding crop. 相似文献
959.
I.M. MacFarlane M.R.C.V.S. 《New Zealand veterinary journal》2013,61(6):160-162
Extract The forty-six herds concerned were tuberculintested in 1950–51 under the provisions of the appropriate section of the Stock Amendment Act, 1945. The same herds were retested in the season 1951–52 at an interval of approximately one year from the date of the first test. 相似文献
960.
Oscar Goñi María T. Sanchez-Ballesta Carmen Merodio María I. Escribano 《Postharvest Biology and Technology》2010,55(3):169-173
In order to obtain a better understanding of the active defense strategy of cherimoya (Annona cherimola Mill.) fruit, hydrolytic and antifungal activity, as well as expression of proteins functionally and immunogenically related to the pathogenesis-related proteins chitinase (PR-Q) and 1,3-β-glucanase (PR-2), were estimated in fruit at different ripening stages. Increase in expression of the 27 kDa constitutive chitinase and the induction of two new proteins, a 26 kDa chitinase and a 51 kDa 1,3-β-glucanase were associated with enhanced in vitro hydrolytic and antifungal activity of the acidic protein extract in ripe fruit. Ripening modified the expression of constitutive basic isoenzymes, with a sharp decrease in both relative accumulation and hydrolytic activity. Likewise, a new basic 33 kDa chitinase was induced in the over-ripe fruit, concomitant with accumulation of a basic constitutive 76 kDa 1,3-β-glucanase. At this stage, the basic protein extract modified in vitro growth inhibition of Botrytis cinerea. Short-term high CO2 treatment delayed fruit ripening and maintained a similar distribution of activity and isoenzymatic pattern in both protein fractions to that in unripe fruit. These results indicate that the changes in the pattern of defense proteins and hydrolytic activity in cherimoyas appear to be associated with ripening. Moreover, unlike the constitutively expressed isoenzymes, only the transitorily induced chitinases and 1,3-β-glucanases were associated with an active defense-related response. 相似文献