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51.
Farm diversification by farmers' open-door policy generates opportunities for farmers to internalize externalities of multifunctionality. Although the educational function of agriculture is an example of such an open-door policy and is attracting growing attention, this function has been little explored. To promote farm diversification in this direction, this paper examined how and to what degree farmers internalize externalities of multifunctionality by focusing on the educational function provided by dairy farming, i.e., farming experience services, in Japan. The main findings were as follows. First, we can say that the educational function is determined by ordinary technical jointness as well as institutional jointness, which is represented by food culture and the agrarian heritage. Both the technical and institutional jointness enhanced the externality. Because of these two working factors, there is a U-shaped relationship between farm diversification and provision of farming experience services. Second, however, an empirical evaluation indicated that farmers only partially internalize educational externalities by treating them as supplementary services combined with processed milk products. Therefore, appropriate integrated management of these newly emerging educational services to become a viable market should be fully addressed in the future, especially for family farms.  相似文献   
52.
Perfluorooctanoic acid (PFOA) has recently attracted attention as a potential health risk following environmental contamination. However, information detailing exposure to perfluorinated carboxylic acids (PFCAs) other than PFOA is limited. We measured the concentrations of PFCAs (from perfluorohexanoic acid to perfluorotetradecanoic acid) in serum samples obtained from patients in Japan (Sendai, Takayama, Kyoto and Osaka) between 2002 and 2009, Korea (Busan and Seoul) between 1994 and 2008 and Vietnam (Hanoi) in 2007/2008. Total PFCA levels (geometric mean) were increased from 8.9 ng mL(-1) to 10.3 ng mL(-1) in Japan; from 7.0 ng mL(-1) to 9.2 ng mL(-1) in Korea; and were estimated at 4.7 ng mL(-1) in Vietnam. PFCAs of greater length than PFOA were significantly increased in Sendai, Takayama and Kyoto, Japan, and levels of long-chain PFCAs exceeded PFOA levels in serum. Among these PFCAs, perfluoroundecanoic acid (PFUnDA) was the predominant component (28.5%), followed by perfluorononanoic acid (PFNA 17.5%), perfluorodecanoic acid (PFDA 7.9%), perfluorotridecanoic acid (PFTrDA 6.1%) and perfluorododecanoic acid (PFDoDA 1.8%). Odd-numbered PFCAs (PFNA, PFUnDA and PFTrDA) were also observed in Korea and Vietnam and their presence increased significantly in Korea between 1994 and 2007/2008. The proportion of long-chain PFCAs in serum was relatively high compared to reports in Western countries. Further investigations into the sources and exposure routes are needed to predict the future trajectory of these serum PFCA levels.  相似文献   
53.
Orally administered 3H‐benzo(a)pyrene (BP) was persistent in protein fraction of liver, lung and kidney. The radioactivity in this fraction increased with time after administration and accounted for about 50%, 40% and 65% of total radioactivity in liver, lung and kidney, respectively at 48 hr. The BP metabolites binding proteins were located in cytosol and had molecular weights of 40,000–60,000 and 80,000–100,000 as determined by gel filtration and polyacrylamide gel disc electrophoresis. In addition, at 48hr after administration, about 80% of radioactivity in high molecular weight protein fraction was found to be precipitated by trichloroacetic acid treatment.

These results suggest that BP metabolites might be transported by and are persistent in these protein fractions of liver, lung and kidney if the intake of BP is continuous. These proteins, therefore, appeared to be closely related to cell toxicity or mutagenicity in these organs as well as DNA.  相似文献   
54.
一组高效稳定纤维素分解菌复合系MC1的筛选及功能   总被引:92,自引:9,他引:83  
从4种堆肥样品中分别筛选出纤维素分解能力较强的4组混合菌,再以酸碱反应互补的原则重新优化组合并驯化成1组纤维素分解能力非常强而稳定的纤维素分解菌复合系MC1.100mL培养物在50℃静止培养72h,分别可分解0.48g滤纸、0.49g脱脂棉、0.19g麦秆和0.08g锯末.分解滤纸时,第24h CMC糖化力最高,为122.3U·mL-在初始pH4~10的不同培养基上接种,均能把pH调到中性,最后稳定在8.0~8.5之间.在连续投放滤纸情况下纤维素分解能力稳定保持20d以上,其发酵液的pH在有滤纸时稳定在6.0~6.5之间,没有滤纸时稳定在8.0~8.5之间.  相似文献   
55.
Measurements of oxidation rate of hydrogen isotopic gases by soil were made to model HT oxidation rate by soil. Soil was sampled at a cultivated farmland and laboratory measurements of the oxidation rate of H(2) and D(2) gases simulating HT gas were carried out under controlled conditions of soil. The oxidation rate increased with increase of H(2) or D(2) concentration in air and nearly saturated at high concentration. The oxidation rate was low under extremely dry and wet soil conditions and was the highest at soil water content of 8-14 w/w%. The oxidation rate increased exponentially with increasing soil temperature and was the highest at 46 degrees C. Michaelis constant K(m) increased exponentially with increasing soil temperature. Oxidation rate of H(2) was generally higher than that of D(2), while K(m) of H(2) was generally lower than that of D(2). From these results, oxidation rate of HT was modeled as a product of the functions that represent dependency on each soil factor.  相似文献   
56.
57.
We investigated PCDDs and related compounds in the blood of young Japanese women, approximately 20 years of age, who had not yet had children, and discussed how the TEQ level of PCDDs and related compounds in their blood may affect the next generation. Means of total TEQ levels were 0.063 pg/g for whole blood basis and 21 pg/g for lipid basis. TEQ of PCDDs, PCDFs and coplanar PCBs accounted for about 43, 34 and 23% of the total TEQ in the whole blood basis, respectively. In the lipid basis, their values were about 44, 34 and 22%, respectively. Previously, we investigated PCDDs and related compounds levels in mother's breast milk, lymphocyte subpopulation and thyroid function of their children, and found negative correlations between the TEQ level of PCDDs and related compounds and CD4+/CD8+, and/or the TEQ level of PCDDs and related compounds and the T4 level in 36 mothers and children. Of these cases, the average age was approximately 28 years. PCDDs and related compounds may be related to immunopathy, such as atopic dermatitis. The effects of PCDDs and related compounds on babies of young Japanese women are important and must be further evaluated.  相似文献   
58.
Total diet study (TDS) samples of 14 food groups from 16 locations in Japan, collected in 1999 and 2000, were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) to estimate the update of daily intake of these contaminants from food. The mean daily intake of toxic equivalency (TEQ) for an adult weighing 50 kg, calculated at non-detected isomer concentrations equal to zero (ND=0), was estimated to be 2.25 pg TEQ/kg b.w./day. When non-detected isomer concentrations are assumed to be equal to half of the limits of detection (ND=1/2 LOD), the mean daily intake was estimated to be 3.22 pg TEQ/kg b.w./day. These values were below the tolerable daily intake (TDI) of 4 pg TEQ/kg b.w. for PCDD/Fs and dioxin-like PCBs set in Japan. In both the estimates, the mean daily intakes were highest from fish and shellfish (76.9% at ND=0 and 53.9% at ND=1/2 LOD of the total TEQs), followed by those from meat and eggs (15.5% at ND=0 and 11.7% at ND=1/2 LOD of the total TEQs). Congener specific data revealed that these total TEQ levels were dominated by 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3,4,4,5-PeCB in each case (71.7% at ND=0 and 63.1% at ND=1/2 LOD of the total TEQs). The dioxin-like PCBs (non-ortho and mono-ortho PCBs) accounted for about 50% of these total TEQs. These data will be very useful in the risk assessment of PCDD/Fs and dioxin-like PCBs from food in Japan.  相似文献   
59.
We measured PCDDs/DFs levels in Japanese human livers and adipose tissues in 1999, and TEQ were calculated with WHO TEF. The mean total levels of PCDDs/DFs in livers and adipose tissues were 57 pg TEQ/g on a lipid basis and 49 pg TEQ/g on a lipid basis, respectively. 1,2,3,6,7,8-HxCDD, 1,2,3,4,6,7,8-HpCDD, OCDD, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, 2,3,4,6,7,8-HxCDF, 1,2,3,7,8,9-HxCDF and 1,2,3,4,6,7,8-HpCDF concentrations in livers considerably differed from those in 1989 (p < 0.05). The mean non-ortho-chlorine substituted biphenyls levels showed 20 pg TEQ/g on a lipid basis and 17 pg TEQ/g on a lipid basis in livers and adipose tissues, respectively. In livers, the mean of 3,3',4,4'-TCB concentrations was 131 pg/g on a lipid basis, and 7.7-fold higher than that in 1989. The mean total mono-ortho-chlorine substituted biphenyls level was 13.0 pg TEQ/g on a lipid basis in livers and 21.6 pg TEQ/g on a lipid basis in adipose tissues. 3,3',4,4',5-PeCB and 3,3',4,4',5,5'-HxCB levels decreased in adipose tissues, and 3,3',4,4',5-PeCB level only decreased in livers. PCDDs, PCDFs, and mono- and non-ortho-chlorine substituted biphenyls levels may have decreased in livers and adipose tissues because of a governmental policy on dioxins discharge for the decade. Then, we estimated the correlations of PCDDs, PCDFs and the related compound levels between livers and adipose tissues. The correlative PCDDs congeners may have had a similar behavior to that between liver and adipose tissue. On the contrary, most PCDFs isomers may have different behavior between liver and adipose tissue, while 2',3,4,4',5-PeCB (IUPAC No. 123) may also have a different behavior between liver and adipose tissue.  相似文献   
60.
Our aim was to clarify the chemical bonding type and stability of heavy metals in industrial waste slag (IWS) by using Fourier transform infrared (FT-IR) spectroscopy. The chemical composition of the IWS sample used in this study was an Al/Si ratio of 0.50 with Fe, Pb, and other minor heavy metals present. The IR peak position of the Si-OSi( M) band (M: Al, Pb, or Fe) was lower for IWS (971 cm−1) than for synthetic Si-Al glass with an Al/Si ratio of 0.5 (1029 cm−1). This implies the formation of covalent Si-O-Pb and Si-O-Fe bonds in the IWS, which caused a shift in the peak position toward a lower wavenumber. FT-IR spectra of synthetic Si-Al-Pb and Si-Al-Fe glasses with various Pb/Si and Fe/Si ratios with a constant Al/Si ratio of 0.5 showed that the peak position of the Si-O-Si(M) band continuously shifted toward lower wavenumbers with increasing Pb/Si and Fe/Si ratios. This suggests that covalent Si-O-Pb and Si-O-Fe bonds are formed in IWS. The comparison of peak positions of the Si-O-Si(M) band between IWS and Si-Al-Fe glass indicated that not only Pb but also other minor heavy metals such as Cu and Cr were included by covalent bonds into the structure of IWS. Therefore, we concluded that most of the heavy metals in IWS formed covalent Si-O-M bodings and were chemically stable.  相似文献   
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