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11.
David L. Pelletier Vivica Kraak Christine McCullum Ulla Unsitalo Robert Rich 《Agriculture and Human Values》1999,16(4):401-419
Community food security (CFS) is an incipient movement based on the re-localization of many food system activities in response to values concerning the social, health, economic, and environmental consequences of the globalizing food system. This study examines the salience of these values based on the action agendas and accomplishments emerging from community planning events in six rural counties of New York, and the nature and type of participation and local support. The study finds a high level of agreement between CFS values as articulated by national leaders in this incipient movement and the action agendas. Further evidence of the salience of these themes is seen in the levels and types of activities and accomplishments taking place 8--12 months after the planning events. However, these follow-through activities appear to have been impeded by a variety of government regulations, uneven levels of support from community organizations and agencies, and a policy environment of fiscal austerity, narrow outcome-oriented accountability, and allocation of agency staff toward special-purpose grants and contracts. Many of these constraints are likely to exist in other communities and are beyond the scope of what community volunteers and practitioners can be expected to address on their own. 相似文献
12.
Ulla Bång 《Potato Research》1989,32(1):101-112
Summary Various haulm treatments and harvest times differentially influenced the incidence of storage rots in potato tubers (Solanum tuberosum L.) in field experiments in Sweden performed over 4 years. The incidence of gangrene caused byPhoma foveata Foister (Phoma exigua var.foveata (Foister) Boerema) increased in cv. Bellona after spraying haulms with diquat as did the amount of infection caused byFusarium avenaceum (Corda ex. Fr.) Sacc. in all three cultivars (Bintje, Bellona, and Magnum Bonum). The lowestP. foveata infection levels occurred after pulling haulms. Late harvesting increased the frequency ofP. foveata in cvs Bintje and Bellona both at 2 and 4 wks interval between haulm treatment and harvest. Tuber and visible stem infection
caused byP. foveata were correlated for cvs Bintje and Bellona, but not for cv. Magnum Bonum. The possible relation between tuber and stem infection
is discussed. 相似文献
13.
Ulla Bång 《Potato Research》1992,35(1):3-15
Summary In each of the five years 1978 to 1982, seed lots of cv. Bintje, variously infested byPhoma foveata Foister andFusarium solani var.coeruleum (Sacc.) Booth, as found by wound and cut tests, respectively, were planted in a series of field experiments at six sites
in Sweden. A statistically significant relationship between seed and progeny infestation was found forP. foveata each year, and in three years forF. solani.
Benomyl and thiabendazole mist treatments of seed tubers at grading in spring controlled the development of gangrene and dry
rot in treated seed tubers, but did not consistently reduce the levels ofP. foveata andF. solani infestation in progeny from treated seed tubers.
The site of cultivation markedly influenced mean levels ofP. foveata infestation, which were found to be related to temperature and rainfall during a 40 day pre-harvest period at the trail sites;
however, mean levels ofF. solani infestation were not so related. 相似文献
14.
Ulla Ahonen Helvi Heinonen-Tanski 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):55-60
Abstract Degradation and leaching of 14C-labelled simazine in coarse sandy soils at 15 + 1°C were investigated using radiometric and mass-spectrometric methods. During 6 months incubation approx. 4–7% of the applied 14C-simazine was evolved as 14CO2. 4–9% of the simazine still remained in the soil. Addition of hen manure or acidification by addition of peat did not clearly influence the rate of degradation of simazine, whereas mechanical treatment significantly increased its degradation. In a nitrogen atmosphere the rate of degradation of simazine was reduced. 9–15% of the simazine or its radioactive metabolites leached through a 33 cm sandy moraine soil column (diameter 6 cm) in ca. 1770 mm of precipitation over a 4 month period, and 2% was leached from a fine sand soil under the same conditions. 相似文献
15.
ABSTRACT The residual nitrogen (N) effect on beetroot following harvested grass-clover (H-ley) or corresponding twice-cut green manure (GM-ley) was compared with a barley control. The residual N at beetroot harvest, calculated as N in beetroot crop and mineral N in the 0–90 cm soil layer, was 83 kg ha?1 for the GM-ley when barley was set to zero. The effect of GM-ley exceeded that of 3H-ley (3 harvests) by 74 kg N ha?1 and 2H-ley (2 harvests) by 42 kg N ha?1. Prediction of residual effects was studied using a model with a humification coefficient (hc) of 0.35 and another with different hc values for different plant materials. The former gave the best fit to observed data in regression analysis. The latter gave the best fit to observed data in absolute values. The residual N effect of GM biomass from summer cuttings corresponded to 40–70% of the potential effect. 相似文献
16.
17.
Formation of benzyl esters from acetic and formic acids during heat treatment of birch at 160–200°C has been studied by gas chromatography. High concentrations of formic and acetic acids formed by the wood itself during hydrothermal treatment were found. The concentrations of acids increased with both treatment time and temperature. The maximum formic- and acetic acid concentrations found at 180°C and after 4 h of treatment performed in this work were 1.1 and 7.2%, based on dry-weight wood, respectively. The treated wood material was characterised by mechanical testing [bending tests perpendicular to the grain, modulus of rupture, modulus of elasticity, Brinell hardness, impact bending and colour measurements (CIE colour space)]. The experiments, where high concentration of acids was formed, showed severe losses in mass and mechanical strength. Indications of possible enhanced mechanical properties for the treated, compared with untreated birch wood were found around 180–200°C at short treatment times. This paper discusses possible degradation reactions coupled with the colour and mechanical properties in relation to acid formation, and suggestions for process optimisations. 相似文献
18.
Ulla Westermark 《Wood Science and Technology》1982,16(1):71-78
Summary The reaction of enzymatically generated superoxide radical with coniferyl alcohol in aqueous solution at pH 8.0 was studied. In the absence of calcium (II) no reaction occurred, but with a calcium (II) concentration of about 50 mM or more, coniferyl alcohol was oxidized by the superoxide radical. Dehydrodiconiferyl alcohol and pinoresinol were identified in the reaction mixture. From this result it is concluded that in the presence of calcium (II) the superoxide radical can achieve a one electron oxidation of coniferyl alcohol.It is suggested that a superoxide-generating enzyme outside the cell wall is responsible for the lignification. This suggestion is based on knowledge of the pore structure of wood cell walls, the high calcium concentration in non-lignified cells, the course of lignification and the existence of superoxide-producing enzyme systems in plant cell walls.The author gratefully acknowledges the skiful technical assistance of Mr. Johan Lindberg 相似文献
19.
Akerström A Jaakola L Bång U Jäderlund A 《Journal of agricultural and food chemistry》2010,58(22):11939-11945
Two data sets are presented to identify the effect of growth location and origin of parental plant on anthocyanidin concentrations in Vaccinium myrtillus fruits. Bilberries were collected from wild populations growing at different latitudes and from cultivated plants originating from different geographical locations but grown in the same location for over 10 years. High-performance liquid chromatography analysis showed that anthocyanidin concentrations varied significantly with latitude and with geographical origin, with higher values form northern latitudes or from a more northerly origin of parent plants. The results show that anthocyanidin concentrations in bilberries are under strong genetic control but are also influenced by climatic factors. Furthermore, the proportions of specific anthocyanidins differed between latitudes and between plants with different parental origins. The diversity in anthocyanidin concentration and composition has important implications for plant breeders and for future development of varieties with high antioxidant capacity. 相似文献
20.
Simonen-Jokinen TL Eskelinen UM Härtel HM Nikunen SK Saloniemi HS Maisi PS 《American journal of veterinary research》2005,66(12):2101-2106
OBJECTIVE: To study gelatinolytic matrix metalloproteinases (MMPs) in tracheobronchial lavage fluid (TBLF) obtained from clinically normal calves and calves with Pasteurella multocida infection. SAMPLE POPULATION: Samples of TBLF obtained from 11 calves with clinical signs of respiratory tract disease and growth of P multocida and Mycoplasma spp during culture of TBLF and samples of TBLF from 6 clinically normal calves with no bacterial growth during culture of TBLF. PROCEDURE: MMPs in TBLF were analyzed by use of gelatin zymography. Gelatinases were identified on the basis of molecular weights and inhibition by EDTA. RESULTS: The main gelatinolytic MMPs detected were the proform (90 to 110 kd) and active form (75 to 85 kd) of MMP-9 (gelatinase B) and the proform (67 to 75 kd) and active form (< 65 kd) of MMP-2 (gelatinase A). Increased amounts of active MMP-2 and MMP-9 were detected in TBLF of calves with respiratory tract disease, compared with amounts of active MMP-2 and MMP-9 in TBLF of clinically normal calves. Concurrent infection with Mycoplasma bovirhinis in calves with pneumonia attributable to P multocida was associated with higher concentrations of MMP-9. CONCLUSIONS AND CLINICAL RELEVANCE: The host response to P multocida includes increases in MMP-2 and MMP-9 concentrations in TBLF. Greater amounts of MMPs detected in calves with concurrent M bovirhinis and P multocida infection indicates synergism between these organisms. 相似文献