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The research described in this paper was designed to identify the factors that influence the importance small-scale farmers place on different marketing channels of short food supply chains. The focus concerns two entirely different types of market that are present in the bigger cities in Hungary: ‘conventional’ markets where there are no restrictions on locality but the farmer-market relationship is based on binding contracts, and newly-emergent farmers’ markets at which only local growers can sell ad hoc, using their own portable facilities. Results are based on a survey that was conducted in 2013 among 156 Hungarian market oriented farmer-vendors at different types of market and confirm that different markets are visited by different types of farmers. Farmers who favour conventional markets are typically less educated, operate on smaller scales and are more committed to their chosen markets via long-term contracts (which reduce the probability of their trying other outlets). The preference for farmers’ markets is stronger with farmers who are more open to cooperation, have specific investment plans for developing their farms and among those who are specifically looking to directly interact with their customers to avoid middlemen. The relevance of the findings is highlighted by the ongoing Short Food Supply Chain Thematic Sub-programme in the present European Union financing period; farmers’ profiles in any given marketing channel must be understood if short food supply chains are to be effectively promoted. Different types of small-scale farmers will benefit from different supporting frameworks, interventions, and initiatives. 相似文献
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Localization of the sheep FcRn in the mammary gland 总被引：5，自引：0，他引：5
Mayer B Zolnai A Frenyó LV Jancsik V Szentirmay Z Hammarström L Kacskovics I 《Veterinary immunology and immunopathology》2002,87(3-4):327-330
Among the multiple functions, which have been identified for the neonatal Fc receptor (FcRn), we study its role in the IgG transport in the mammary gland during the colostrum formation. For this reason, we have obtained several mammary gland biopsies from a pregnant sheep around parturition. The presence of the FcRn heavy chain mRNA was detected exclusively in the acinar and ductal epithelial cell by in situ hybridization (ISH). We detected strong signal in samples harvested 24 and 10 days prepartum; however, in samples we collected postpartum was barely detectable. Immunohistochemistry confirmed our ISH data. The cytoplasm of the epithelial cells of the acini and ducts in the mammary gland biopsies stained homogeneously before parturition, although a remarkable difference was observed in the pattern after lambing. The signal indicated uneven distribution of the FcRn alpha chain in the epithelial cells 1 and 5 days postpartum, since the apical sides of the epithelial cells were highlighted. The presence of the FcRn in the acinar and ductal epithelial cells and the obvious change of its distribution before and after parturition suggest that FcRn plays an important role in the IgG transport during colostrum formation. FcRn expression was also found in the lamb duodenal crypt epithelial cells, which have been previously demonstrated to secrete IgG1 in newborn ruminants, suggesting secretory role of the FcRn in ruminant epithelial cells. 相似文献
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Background
The Agrobacterium vacuum (Bechtold et al 1993) and floral-dip (Clough and Bent 1998) are very efficient methods for generating transgenic Arabidopsis plants. These methods allow plant transformation without the need for tissue culture. Large volumes of bacterial cultures grown in liquid media are necessary for both of these transformation methods. This limits the number of transformations that can be done at a given time due to the need for expensive large shakers and limited space on them. Additionally, the bacterial colonies derived from solid media necessary for starting these liquid cultures often fail to grow in such large volumes. Therefore the optimum stage of plant material for transformation is often missed and new plant material needs to be grown. 相似文献34.
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Effect of prepubertal ovariohysterectomy on bone mineral density and bone mineral content in puppies
Ekici H Sontas BH Toydemir TS Senmevsim O Kabasakal L Imre Y 《Acta veterinaria Hungarica》2005,53(4):469-478
In this study, dual energy X-ray absorptiometry (DXA) was performed on the calcaneus (CAL) and accessory carpal bone (ACB) of early-age neutered (n = 11) and sham-operated puppies (n = 10) to investigate changes in bone mineral density (BMD) and bone mineral content (BMC) over time. Prepubertal ovariohysterectomy and sham surgery were performed at 10 weeks, while BMD and BMC were measured at 12, 16, 20 and 24 weeks of age. BMD and BMC of CAL and ACB of ovariohysterectomised puppies were found to be higher. The differences between the groups were statistically unimportant; however, the fourth measurement of the ACB showed a significant (P < 0.05) difference. Sexually intact puppies weighed less than gonadectomised puppies in all measurements. Because of the positive correlations between body weight and bone mineral density, BMD and BMC of early-age neutered puppies were found to be higher. These results suggest that BMD and BMC are not affected by prepubertal ovariohysterectomy until six months of age in mixed-breed puppies. 相似文献
36.
Mayer B Kis Z Kaján G Frenyó LV Hammarström L Kacskovics I 《Veterinary immunology and immunopathology》2004,98(1-2):85-89
In neonatal calves, maternal immunoglobulin (Ig) is transferred into respiratory secretion which contributes to protection against pathogens. The early predominance of IgG1 in respiratory tract secretions is progressively reduced in favor of IgA by age but in the lower, bronchoalveolar system secreted IgG remains the dominant secreted Ig even in adulthood. The trans-epithelial transport of secretory IgA into mucosal secretions is carried out by the polymeric Ig receptor. However, the mechanism by which IgG crosses epithelial cells to provide defense on mucosal surfaces is still unknown. In order to investigate the possibility that the neonatal Fc receptor, FcRn is involved in this transport we have first analyzed the localization of this receptor in the upper and lower respiratory tracts. Consistent with the in situ hybridization data, immunohistochemistry showed undetectable expression in the tracheal epithelial cells, relatively weak expression in epithelial cells of the bronchi, apparent staining those lining the bronchioli and randomly scattered signal over the alveolar tissue. The bovine FcRn may thus play a role in IgG transport across mucosal epithelial barriers as a trafficking receptor and ensure IgG predominance in the lower respiratory tract. 相似文献
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Finian Bannon Gerrit Gort Gerard van Leeuwen Imre Holb Mike Jeger 《Agricultural and Forest Meteorology》2009,149(3-4):518-525
The aerial concentration of Monilinia fructigena (causing brown rot in pome fruit) conidia was sampled during 1997 and 1998 in an apple orchard and was related to weather conditions. The highest hourly concentration measured in 1997 was 230 conidia/m3, in 1998 concentrations were lower than in 1997 throughout the season. In both years concentrations were highest in the afternoon hours. Generalised linear models, employing a Poisson distribution for the spore counts and a logarithm link function, were used to study the relationships between spore counts and lagged weather variables. In 1997 the best fitting model had variables temperature lagged at 100 h, an east–west component of wind direction, and wind speed; whereas in 1998 the best model included in addition an effect of relative humidity. Temperature and wind direction had consistent effects on hourly spore counts in both years, but whereas temperature has a biologically relevant effect on spore production and maturation, the effect of wind direction is likely to reflect the purely local effect of orchard layout. Results are compared with observations made in stone fruit orchards where Monilinia laxa and Monilinia fructicola are the predominant species, and differences in epidemiology between these systems are discussed. 相似文献
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Robert F Vuataz G Pollien P Saucy F Alonso MI Bauwens I Blank I 《Journal of agricultural and food chemistry》2004,52(22):6837-6842
The formation of acrylamide in crystalline model systems based on asparagine and reducing sugars was investigated under low-moisture reaction conditions. The acrylamide amounts were correlated with physical changes occurring during the reaction. Molecular mobility of the precursors turned out to be a critical parameter in solid systems, which is linked to the melting behavior and the release of crystallization water of the reaction sample. Heating binary mixtures of asparagine monohydrate and anhydrous reducing sugars led to higher acrylamide amounts in the presence of fructose compared to glucose. Differential scanning calorimetry measurements performed in open systems indicated melting of fructose at 126 degrees C, whereas glucose and galactose fused at 157 and 172 degrees C, respectively. However, glucose was the most reactive and fructose the least efficient sugar in anhydrous liquid systems, indicating that at given molecular mobility the chemical reactivity of the sugar was the major driver in acrylamide formation. Furthermore, reaction time and temperature were found to be covariant parameters: acrylamide was preferably formed by reacting glucose and asparagine at 120 degrees C for 60 min, whereas 160 degrees C was required at shorter reaction time (5 min). These results suggest that, in addition to the chemical reactivity of ingredients, their physical state as well as reaction temperature and time would influence the formation of acrylamide during food processing. 相似文献
40.
Robert F Héritier J Quiquerez J Simian H Blank I 《Journal of agricultural and food chemistry》2004,52(11):3525-3529
Parallel synthesis was applied to prepare a series of 3-(acetylthio)-2-alkyl alkanals by Michael addition of thioacetic acid under alkaline conditions to alpha,beta-unsaturated 2-alkyl-substituted aldehydes, which were obtained by aldol condensation of the corresponding primary aldehydes as starting materials. The target compounds were characterized in terms of GC, MS, and NMR data. The sensory properties of the odorants, such as odor quality and odor detection threshold value, were determined with a trained panel. Structure-activity relationships are discussed, suggesting that the 1,3-oxygen-sulfur functionality, required for the "olfactophore" of tropical/vegetable notes, can further be extended to the acetylthio derivatives. 相似文献