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91.
Marine biofouling is a natural process that represents major economic, environmental, and health concerns. Some booster biocides have been used in biofouling control, however, they were found to accumulate in environmental compartments, showing negative effects on marine organisms. Therefore, it is urgent to develop new eco-friendly alternatives. Phenyl ketones, such as benzophenones and acetophenones, have been described as modulators of several biological activities, including antifouling activity (AF). In this work, acetophenones were combined with other chemical substrates through a 1,2,3-triazole ring, a strategy commonly used in Medicinal Chemistry. In our approach, a library of 14 new acetophenone–triazole hybrids was obtained through the copper(I)-catalyzed alkyne-azide cycloaddition “click” reaction. All of the synthesized compounds were evaluated against the settlement of a representative macrofouling species, Mytilus galloprovincialis, as well as on biofilm-forming marine microorganisms, including bacteria and fungi. The growth of the microalgae Navicula sp. was also evaluated after exposure to the most promising compounds. While compounds 6a, 7a, and 9a caused significant inhibition of the settlement of mussel larvae, compounds 3b, 4b, and 7b were able to inhibit Roseobacter litoralis bacterial biofilm growth. Interestingly, acetophenone 7a displayed activity against both mussel larvae and the microalgae Navicula sp., suggesting a complementary action of this compound against macro- and microfouling species. The most potent compounds (6a, 7a, and 9a) also showed to be less toxic to the non-target species Artemia salina than the biocide Econea®. Regarding both AF potency and ecotoxicity activity evaluation, acetophenones 7a and 9a were put forward in this work as promising eco-friendly AF agents.  相似文献   
92.
Soil salinity and sodicity are land degradation processes that strongly alter soil quality and consequently plant productivity. The reclamation of soils affected by salinity and/or sodicity is an important goal to maintain the sustainability of production. The objectives of this review were (1) to investigate the effectiveness of different organic amendments to reclaim saline/sodic soils and improve environmental quality and productivity of agro-ecosystems and (2) to provide useful information on the most appropriate waste management for minimizing any potential risks. To achieve these aims, recently published literature, related to field and laboratory studies, considering the effects of a wide range of organic amendments on main soil properties, was collected. Results of these studies underline that input of exogenous organic matter (manure, plant residues, by-product of farming or municipal activities, etc.) can be a feasible way to reclaim soils with serious problems of salinity and sodicity. Optimal rates (not greater than 50 t ha?1) of different organic amendments can improve physical (soil structure, permeability, water holding capacity, etc.) and chemical (pH, cation exchangeable capacity, etc.) soil properties, favoring plant growth and microbial activity, without any risks for the environment (subsoil and groundwater contamination). Of course, it is very important to characterize carefully the organic wastes before their use in agriculture and optimize their management, for avoiding further land degradation.  相似文献   
93.
Landscape Ecology - In the last 30 years, the number of golf courses has increased dramatically worldwide. Since no other sport occupies and manages such large areas of green space, landscape...  相似文献   
94.
The common bean (Phaseolus vulgaris L.) is the most consumed legume in the world. In Portugal, the geographic isolation of the region surrounded by the mountainous barrier of Peneda-Gerês, Barroso and Marão is thought to have the safeguard of a large number of adapted bean populations. In order to assess the value of this germplasm to breeding programs, a study of 20 Portuguese landraces collected in this Northern region were evaluated for agronomical (days to flowering, plant height, days to harvest, weight of seeds per plant and 100 seeds weight), chemical (crude protein) and genetic diversity (microsatellite DNA).  相似文献   
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This study investigated for the first time the reproductive biology of Prochilodus lineatus in a system of rivers in southeastern Brasil, relating it to the role of tributary rivers in the reproductive success of this important commercial fish in the Upper Paraná River basin, where a cascade of hydroelectric dams were deployed. Specimens were caught bimonthly in three river sites: (S1) Grande River, downstream from the Porto Colômbia dam; (S2) Pardo River; and (S3) Mogi Guaçu River. Sex steroid plasma levels, fecundity, follicular atresia, oocyte diameter and gonadosomatic index (GSI) were compared among sites. In S1, fish exhibited changes in the reproductive parameters: lower GSI, oocyte diameter and fecundity and higher follicular atresia index, when compared to S2 and S3. Frequency of maturing fish was higher in S3 and spawning was only registered in S3. In sites S2 and S3, plasma concentrations of testosterone and 17β-estradiol in females and testosterone in males showed wide variations following gonadal maturation. Fish from S1 showed few significant variations in sex steroid concentrations throughout the gonadal cycle. These results indicate that P. lineatus does not reproduce in Grande River (S1), but probably uses the Pardo River (S2) as a migratory route towards the Mogi Guaçu River (S3) where they complete gonadal maturation and spawning. Our findings contribute for understanding the reproductive biology of P. lineatus and to highlight the importance of tributaries in impounded rivers as a favourable environment for migration and spawning of fish.  相似文献   
96.
Crop residues and tillage are being advocated for their potential effectiveness to modify the soil hydrothermal regime. This study was carried out to quantify the effect of straw mulching and rotary hoeing on the soil water and thermal regimes of a loess soil. The field experiment consisted of four treatments: (1) no mulching and no rotary hoeing as control, (2) rotary hoeing, (3) wheat straw mulching, and (4) wheat straw mulching with rotary hoeing. During the study period from 5 August to 20 September 2002, soil water content and pressure head were measured daily at five soil depths (0.05, 0.15, 0.30, 0.45 and 0.60 m). Soil temperatures were measured at hourly resolution at three depths (0.05, 0.15 and 0.30 m). Mulching decreased soil water loss on an average by 0.39 mm d−1 and rotary hoeing increased water loss on an average by 0.12 mm d−1 as compared to control. Volumetric soil water contents at pF 1, 1.8 and 2.5 up to 30 cm depth were highest (0.418, 0.390, and 0.360 m3 m−3, respectively) with the application of wheat straw mulch and lowest (0.393, 0.363, and 0.333 m3 m−3, respectively) with the rotary hoeing. Soil thermal conductivity measured at pF 1, 1.8, 2.5, 3, and 3.7 decreased with increasing suctions in all the treatments. However, the tillage and mulching did not affect the soil thermal conductivity. Further, compared with the control, mulching reduced average soil temperatures by 0.74, 0.66, 0.58 °C at 0.05, 0.15, and 0.30 m, respectively, during the study period. The rotary hoeing tillage slightly increased the average soil temperature by 0.21 °C at 0.05 m depth compared to control. The tillage effect did not transmit to deeper depths. The numerical model Hydrus-1D was used to simulate the water and temperature regimes of the treatments. Simulations with hydraulic parameters derived from laboratory measurements did not yield satisfactory results. Only when the hydraulic parameters were optimized by the inverse method, simulations performed well. The largest deviations were observed in the wheat straw mulching treatment. Simulations were further improved by adjusting the potential evaporation rate from the measured data which was achieved by linking the inversion code UCODE to the Hydrus-1D. Soil temperatures at 0.05 and 0.15 m in all the treatments were modeled well, yielding root mean square errors between 0.3 and 1.7 °C. As for soil water, the largest temperature deviations were found for the mulching treatment. All simulations underestimated soil temperatures at 0.30 m. In conclusion, crop residue can be utilized as mulching to improve the soil hydrothermal regime and the Hydrus-1D model can be used as a tool for analyzing water and heat transport processes and for estimating hydraulic transport parameters under field conditions.  相似文献   
97.
Rye and wheat bran are excellent natural sources of plant sterols in the diet. Their content, however, may vary according to processing. Thermal (roasting and heating in a microwave oven), mechanical (milling and cryogenic grinding), and enzymatic treatments (hydrolysis with xylanase or beta-glucanase or a mixture of these two enzymes) were performed, and their effect on sterol content, extractability of sterols and the characteristic steryl conjugates of cereals (steryl ferulates, steryl glycosides, and acylated steryl glycosides) were studied. Mechanical and enzymatic treatments increased the apparent sterol content, whereas aqueous processing without enzymes hindered the availability of total sterols, especially from rye bran. Changes were also seen in the amounts of steryl conjugates caused by the enzymatic treatments. On the basis of the results of this study, it can be speculated that a combination of fine particle size and enzymatic processing results in optimal sterol availability in cereal processing.  相似文献   
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We herein report a case of a double aortic arch in a 10-week-old male dog of no defined race, which presented episodes of regurgitation at the time of weaning. This vascular malformation was characterized by the persistence of two aortic arches, right and left, of varying dimensions. The right aortic arch was observed to be larger. During post mortem examination the vessels of the animal were injected with coloured latex bi-centrifuged CIS 1-4 polisopreno which revealed the patency of the two aortic arches. Concomitantly, dilation of the cranial oesophagus causing constriction was observed, indicating megaesophagus. Apart from the constriction, the oesophagus presented normal morphometric parameters in relation to its dimensions.  相似文献   
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