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41.
The antioxidant activity of berry phenolics (at concentrations of 1.4, 4.2, and 8.4 mug of purified extracts/mL of liposome sample) such as anthocyanins, ellagitannins, and proanthocyanidins from raspberry (Rubus idaeus), bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), and black currant (Ribes nigrum) was investigated in a lactalbumin-liposome system. The extent of protein oxidation was measured by determining the loss of tryptophan fluorescence and formation of protein carbonyl compounds and that of lipid oxidation by conjugated diene hydroperoxides and hexanal analyses. The antioxidant protection toward lipid oxidation was best provided by lingonberry and bilberry phenolics followed by black currant and raspberry phenolics. Bilberry and raspberry phenolics exhibited the best overall antioxidant activity toward protein oxidation. Proanthocyanidins, especially the dimeric and trimeric forms, in lingonberries were among the most active phenolic constituents toward both lipid and protein oxidation. In bilberries and black currants, anthocyanins contributed the most to the antioxidant effect by inhibiting the formation of both hexanal and protein carbonyls. In raspberries, ellagitannins were responsible for the antioxidant activity. While the antioxidant effect of berry proanthocyanidins and anthocyanins was dose-dependent, ellagitannins appeared to be equally active at all concentrations. In conclusion, berries are rich in monomeric and polymeric phenolic compounds providing protection toward both lipid and protein oxidation.  相似文献   
42.

Purpose  

A small-scale bioremediation assay was developed in order to get insight into the functioning of a polychlorinated biphenyl (PCB) degrading community during the time course of bioremediation treatment of a contaminated soil. The study was conducted with the aim to better understand the key mechanisms involved in PCB-removal from soils.  相似文献   
43.
Objective To use the American College of Veterinary Internal Medicine (ACVIM) validation criteria to evaluate the performance of high definition oscillometric (HDO) and Doppler blood pressure measurement techniques against invasive blood pressure measurements in anaesthetized dogs. Study design Prospective clinical study. Animals Twenty client‐owned dogs. Materials and Methods Invasive blood pressure was measured using a catheter inserted into a pedal artery and an electronic transducer. The sites of cuff placement for the HDO measurements were the mid antebrachium or the proximal tail and, for the Doppler technique, the distal tibia. Agreement between invasive and non‐invasive blood pressure measurements was estimated by the Bland–Altman method. Results Only 10% and 34% of Doppler measurements were within 10 and 20 mmHg of invasive blood pressure values, respectively. The Doppler device failed to meet the ACVIM validation criteria for blood pressure measurement devices. The best agreement between HDO and invasive blood pressure measurement technique was observed for mean arterial blood pressure (MAP); 67% and 95% of readings were within 10 and 20 mmHg of invasive blood pressure values respectively. In addition, 52% and 87% of diastolic arterial blood pressure (DAP) measurements were within 10 and 20 mmHg of invasive readings. High definition oscillometric readings did not meet ACVIM recommended limits for SAP. Conclusion and clinical relevance The Doppler technique overestimated and the HDO device showed limited agreement with invasive blood pressure measurement in anaesthetized dogs. High definition oscillometry met most of the ACVIM requirements for MAP and DAP while the Doppler technique did not.  相似文献   
44.
Jigging with artificial lights (squid jigging) and deploying of large scale trap-net (also known as a set-net in Japan), are the major methods to capture Japanese common squid Todarodes pacificus in western Japan. Squid jigging is a highly selective fishing method. However, it consumes large amount of energy for steaming to the fishing ground and for lighting. In contrast, trap-net fishing requires substantially less energy but its capture efficiency is strongly influenced by its stationary mode of capture. The primary objective of this study was to analyze how various environmental and biological factors such as the lunar cycle, tidal condition, wind direction and squid abundance affect the capture efficiency of squid jigging and trap-net fishing. We analyzed the effect of these factors on squid catch in five Fisheries Cooperative Associations located on four islands in Nagasaki Prefecture, western Japan. Our analysis shows that squid catch in jigging and trap-net fishing is mainly influenced by the lunar cycle but also tide and wind direction play a marked role. In addition, squid abundance significantly affects the catches in trap-net fishing. Recommendations are made to improve the overall profitability of squid fishing by proper choice of the capture method, location and season.  相似文献   
45.
46.
We present stationarity criteria for forest stands,and establish embodiments using a Norwegian empirical stand development model.The natural stationary states only slightly differ from the outcome of long-term simulations previously implemented using the same empirical model.Human interference in terms of diameter-limit cutting is introduced.Consequently,stationary states differing from the natural one appear.Standing volume,growth and monetary value appear low but the financial return rate may be significant.Volume yield and financial return clearly contradict each other,the former arising from harvesting large trees,the latter from frequent removal of small trees.An exponential tree size distribution does not appear to comply with the stationarity criterion.  相似文献   
47.
The Taita Hills are the northernmost part of the Eastern Arc Mountains of Kenya and Tanzania, which is one of the most important regions for biological conservation in the world. The indigenous cloud forests in this area have suffered substantial degradation for several centuries due to agricultural expansion. In the Taita Hills, currently only 1% of the original forested area remains preserved. In order to create effective policies to preserve the natural resources and biodiversity of the Eastern Arc Mountains it is crucial to understand the causes and interactions involved in the landscape changes in the most degraded areas. The research presented here aimed to understand the role of landscape attributes and infrastructure components as driving forces of agricultural expansion in the Taita Hills. Geospatial technology tools and a landscape dynamic simulation model were integrated to identify and evaluate the driving forces of agricultural expansion and simulate future landscape scenarios. The results indicate that, if current trends persist, agricultural areas will occupy roughly 60% of the study area by 2030. Agricultural expansion will likely take place predominantly in lowlands and foothills throughout the next 20 years, increasing the spatial dependence on distance to rivers and other water bodies. The main factors driving the spatial distribution of new croplands were the distance to markets, proximity to already established agricultural areas and distance to roads. Other driving forces of the agricultural expansion, as well as their implications for natural resources conservation, are discussed. Further studies are necessary to integrate the effects of population pressure and climate change on the sustainability and characteristics of local agricultural systems.  相似文献   
48.
A series of experiments were carried out to investigate the colour stability of chemically treated and thermally modified wood compared to non-modified wood during long term artificial UV light irradiation. One set of wood samples was vacuum-pressure impregnated with alkaline (pH 9.8) copper (II) ethanolamine aqueous solution, while another set of samples from the same wood block was thermally modified at 210°C and −0.90 bar for 2 h. The treated and modified wood samples along with the non-modified ones were exposed to artificial UV light with the wave length in the region of UVA (315–400 nm) and UVB (280–315 nm) intermittently for 500 h. Colour measurements were carried out throughout the irradiation period at an interval of 100 h according to CIEL*a*b* system, where the results are presented in terms of ΔE, ΔL*, Δa* and Δb* values. Better photo-stability in terms of colour changes was recorded for both treated and modified woods compared to the non-modified one. By means of EPR and DRIFT spectroscopic study it was shown that some degree of colour stability of treated and modified woods, achieved during artificial UV light irradiation, resulted from lignin modifications and monomers of phenolic compounds.  相似文献   
49.
Cloudberries ( Rubus chamaemorus ) contain phenolics (mainly ellagitannins), which have recently been related to many valuable bioactivity properties. In general, phenolics are known to react readily with various components, which may create an obstacle in producing stable functional components for food and pharmaceutical purposes. In this study, the aim was to improve the storage stability of cloudberry phenolic extract by microencapsulation. The phenolic-rich cloudberry extract was encapsulated in maltodextrins DE5-8 and DE18.5 by freeze-drying. Water sorption properties and glass transition temperatures (T(g)) of microcapsules and maltodextrins were determined. Microcapsules together with unencapsulated cloudberry extract were stored at different relative vapor pressures (0, 33, and 66% RVP) at 25 degrees C for 64 days, and storage stability was evaluated by analyzing phenolic content and antioxidant activity. Compared to maltodextrin DE18.5, maltodextrin DE5-8 had not only higher encapsulation yield and efficiency but also offered better protection for phenolics during storage. Without encapsulation the storage stability of cloudberry phenolics was weaker with higher storage RVP. Microencapsulation improved the storage stability of cloudberry phenolics. The physical state of microcapsules did not have a significant role in the stability of cloudberry phenolics because phenolic losses were observed also in amorphous glassy materials. The antioxidant activity of the microencapsulated cloudberry extract remained the same or even improved slightly during storage, which may be related to the changes in phenolic profiles.  相似文献   
50.
The rate of thermal degradation of wood as a function of the extent of heat-bath treatment was investigated. At both 150°C and 170°C, the rate of degradation increased along with increasing relative humidity in the heating atmosphere. However, up to intermediate relative humidity (in the vicinity of 50%), the higher the temperature, the less was the effect of increasing relative humidity on the degradation rate. Furthermore, the greater the relative humidity, the less was the effect of increasing temperature on the degradation rate. On the other hand, between intermediate relative humidity and water-saturated conditions, the effect of increasing relative humidity on the degradation rate was the same regardless of the temperature, and the effect of increasing temperature on the degradation rate was the same regardless of the relative humidity. In moist conditions, significant thermal degradation occurred at temperatures as low as 150°C.  相似文献   
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