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101.
Regional institutional marketing supports sustainable farming by bringing wholesome, nutritious food to members of the community.
Schools, in particular, can benefit greatly from this arrangement in comprehensive efforts to address childhood obesity. Nineteen
previous publications examined issues around supply of and/or demand for regional food procurement by institutions across
the United States, including levels of interest, perceived benefits, and barriers to this arrangement. Food service directors,
farmers, and/or distributors participated in surveys, interviews, workshops/forums, case studies, and one evaluation about
regional food procurement. Accounts of seven farmer cooperatives or networks indicate that institutional customers are more
often restaurants (n = 5), health care facilities (n = 2), colleges/universities (n = 2), and other facilities (n = 2), than public schools (n = 1) or food retailers (n = 1). The studies agree that the main benefits offered by regional food procurement are support of the local economy and increased
access to fresh and nutritious food. Barriers consistently faced by food services and farmers have to do with lack of infrastructure
and financial support for processing and central distribution. Though obstacles vary by district and/or geographic characteristics,
results indicate that across groups there is a clear need for better support mechanisms by which farms can connect with regional
markets. The practice of farm-to-institution marketing holds the potential to improve nutritional status of community members
and financial stability of farmers, though institutional support is needed for systemic transition to this purchasing method.
相似文献
Rainbow A. VogtEmail: |
102.
Vogt RE Cummings AC Garrard TL Gehrels N Stone EC Trainor JH Schardt AW Conlon TF McDonald FB 《Science (New York, N.Y.)》1979,206(4421):984-987
The Voyager 2 encounter has enhanced our understanding of earlier results and provided measurements beyond 160 Jupiter radii (R(J)) in the magnetotail. Significant fluxes of energetic sulfur and oxygen nuclei (4 to 15 million electron volts per nucleon) of Jovian origin were observed inside 25 R(J), and the gradient in phase space density at 12 R(J) indicates that the ions are diffusing inward. A substantially longer time delay versus distance was found for proton flux maxima in the active hemisphere in the magnetotail at Jovicentric longitudes lambda(III), = 260 degrees to 320 degrees than in the inactive hemisphere at lambda(III), = 85 degrees to l10 degrees . These delays can be related to the radial motion of plasma expanding into the magnetotail, and differences in the expansion speeds between the active and inactive hemispheres can produce rarefaction regions in trapped particles. It is suggested that the 10-hour modulation of interplanetary Jovian electrons may be associated with the arrival at the dawn magnetopause of a rarefaction region each planetary rotation. 相似文献
103.
A Matini Behzad B Ebrahimi AR Alizadeh V Esmaeili A Dalman L Rashki AH Shahverdi 《Reproduction in domestic animals》2014,49(4):599-605
Our aim was to evaluate the effects of fish oil feeding on sperm classical parameters, level of reactive oxygen spices (ROS), spermatozoa death incidence and in vitro fertilization (IVF) rate in rams. We randomly assigned nine rams, into two experimental groups (isoenergetic and isonitrogenous rations with constant level of vitamin E supplement): control (CTR; n = 5) and fish oil (FO; n = 4, 35 g/day/ram). Diets were fed for 70 days during the physiological breeding season. After a 21‐day dietary adaptation period, semen was collected weekly from each ram by an artificial vagina. Sperm classical parameters were determined by the computer‐assisted sperm analyzer system (CASA), and it was prepared for IVF process by swim‐up technique. These evaluations were performed during the first and last weeks of sampling. Intracellular ROS level and spermatozoa death incidence were detected by flow cytometry on a weekly basis after adaptation. Data were analysed with SPSS 15. The volume, concentration (3.6 and 2.7 × 109/ml) and sperm progressive motility (60 and 48%) were significantly improved in the FO group compared with the CTR (p < 0.05). A comparison of two‐cell stage embryos following IVF in the two groups showed a significantly higher fertilization rate in the FO group (56%) compared with the CTR (49%). Superoxide anion (O2?) rate was significantly lower (p < 0.05) at the third week of sampling in the FO. Although the H2O2 rate was numerically lower in the FO group compared with the CTR, this difference was not significant. In addition, apoptosis showed a significant difference in the third week of sampling (15 and 30% for FO and CTR, respectively; p < 0.05). Overall, adding fish oil to the ram diet not only improved sperm quality and IVF results, it also could reduce oxygen‐free radicals and the incidence of spermatozoa death. 相似文献
104.
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106.
Composting of yard waste and sludge/yard waste mixtures was investigated during laboratory and field testing. A strong correlation between moisture content and windrow peak temperatures was observed. Odors were detected at cocomposting windrows when temperatures exceeded 54°C. The sludge to yard waste mixture ratio was found to affect resulting compost particle size and, consequently, oxygen transport. Compost quality was excellent, with pesticides below detection level and low concentrations of heavy metals. 相似文献
107.
The increasing appearance of rods (»Stäbchen«) being found in Heterobasidion annosum cultures was investigated. They proved to be neither bacterial impurities nor fomannosin but calcium oxalates. The number of rod-shaped crystals depended on the quality of the tap water taken for the culture medium and on genetical aspects. The importance of calciumoxalates being formed by H. annosum is discussed. 相似文献
108.
S. J. KAY A. AH CHEE P. O. SALE J. T. TAYLOR E. HADAR Y. HADAR R. L. FARRELL 《Forest Pathology》2002,32(2):109-121
Sphaeropsis sapinea is a pathogen of many coniferous species and causes significant losses to the plantation forestry industries of many countries. New Zealand isolates of S. sapinea were examined for colony and morphological characteristics, and pathogenicity to Pinus radiata seedlings. Considerable variation was observed in colony growth form and colour, and in the growth rates on four agar media. The conidial dimensions, carbon and nitrogen utilization, and pathogenicity also varied among the isolates. The variation observed was such that the isolates could not be placed within previously described distinct morphotypes and the present results concur with previous studies cautioning the use of morphological criteria alone to partition the species. These results contrast markedly with previous reports and seemingly indicate a change in the New Zealand S. sapinea population. This difference may reflect the re‐introduction or spread of additional isolates or a shift in the structure of the resident population. 相似文献
109.
In acid forest soils pores draining under conditions of low water tension contain a solution usually differing in composition from the equilibrium solution of the bulk soil. For tree nutrition, the former was described as comparable to the bulk soil solution or less favourable. Our recent work on solution quality contradicted the universal validity of these findings. It turned out that the methods usually recommended tend to consistently reproduce the pattern of more advanced acidification of coarse pores. We applied our combination of methods to a range of soils to find out whether our previous finding of more favourable solution conditions in undisturbed soil samples as compared to the bulk soil is common or rather an exception. Undisturbed cores and bulk soil were sampled from four forested sites differing in pH and base saturation. We used an iterative procedure to adjust the equilibrium soil solution of disturbed soil and a water extraction with a soil:solution ratio of 1:2. To extract solution from undisturbed soil cores only small volumes of water were added, and we distinguished analytically between total (by ICP) and ionic (by CE) concentrations of cations. We calculated Ca/Al molar ratios and the fraction of (Al3+ + H+) on total cationic charge in solution as criteria for solution quality. Whereas with total concentrations, there always appeared to be less favourable conditions in the soil pore solution, free ionic concentrations allowed a differentiation between the soils. In view of plant nutrition, the quality of the soil solution from undisturbed samples was better, equal to, or worse than that of the bulk soil, suggesting that forest sites represent a continuum with respect to these chemical gradients. Even in soils where gradients are not observed it is not necessary to assume an equilibrium achieved by internal processes to exist between coarse pores and the bulk soil. 相似文献
110.
R.D. Vogt H.M. Seip H. Orefellen G. Skotte C. Irgens J. Tyszka 《Water, air, and soil pollution》2001,130(1-4):1445-1450
Precipitation, soils and soil water in a forested catchment in western Poland have been studied during the period 1992 – 96 (see also Vogt et al., this conf.). The S-deposition in the area during the study period was 2 – 3g S m?2 yr?1. In spite of decreasing anthropogenic emissions the S-deposition in the area did not change much during the study period mainly because the first years were exceptionally dry. However, the S-deposition was considerably higher during the previous decade. Based on soil water sulphate concentration, pH, acid neutralising capacity and the ratio of Al3+/(Ca2+ + Mg2+), there is apparently an amelioration in the conditions. A study using inter alia principal component analysis, indicates that this improvement is mainly due to more precipitation in the later part of the study period. Variations in precipitation amount have a pronounced effect on the soil-water chemistry, which makes it difficult to establish trends caused by changes in anthropogenic deposition. Long time series are therefore necessary to establish recovery due to reduced S-emissions. 相似文献