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11.
Brantsaeter AL Haugen M Rasmussen SE Alexander J Samuelsen SO Meltzer HM 《Public health nutrition》2007,10(8):838-847
OBJECTIVE: To validate a new food-frequency questionnaire (FFQ) for measuring the intake of fruit, vegetables and tea reported by women participating in the Norwegian Mother and Child Cohort Study (MoBa). DESIGN: Intake of fruits, vegetables and tea estimated by the FFQ was compared with urinary flavonoid excretion, plasma carotenoid concentration and intake measured by a 4-day weighed food diary (FD). The triangular method was applied to calculate FFQ validity coefficients using two independent biomarkers. SETTING AND SUBJECTS: One hundred and nineteen women participating in MoBa. RESULTS: The FFQ estimate of fruit intake was significantly correlated with urine phloretin (r = 0.33), citrus fruit/juice with urine hesperetin (r = 0.44), cooked vegetables with plasma alpha-carotene (r = 0.37), and tea with urine kaempferol (r = 0.41) (P < 0.01 for all). On average, 60% of the participants fell into the same or adjacent quintiles when classified by FFQ and biomarkers. Significant correlations between the FFQ and FD were found for fruit (r = 0.39), vegetables (r = 0.34), juices (r = 0.50) and tea (r = 0.53). The FFQ validity coefficient was 0.65 for citrus fruit/juice and 0.59 for cooked vegetables as calculated by the triangular method. CONCLUSIONS: The validation study shows that the MoBa FFQ can be used to estimate fruit, juice, vegetable and tea intake in pregnant Norwegian women, and to rank individuals within the distribution. 相似文献
12.
Effects of Restored Stream Buffers on Water Quality in Non-tidal Streams in the Choptank River Basin
Adrienne J. Sutton Thomas R. Fisher Anne B. Gustafson 《Water, air, and soil pollution》2010,208(1-4):101-118
Restoration of riparian buffers is an important component of nutrient reduction strategies in the Chesapeake Bay watershed. In 1998, Maryland adopted a Conservation Reserve Enhancement Program (CREP), which provides financial incentives to take agricultural land out of production to plant streamside vegetation. Between 1998 and 2005, 1–30% of streamside vegetation (average?=?11%), was restored to forest or managed grass in 15 agriculturally dominated sub-basins in the Choptank River basin, a tributary of Chesapeake Bay. Pre-existing forested buffers represented 10–48% of the streamside (average?=?33%), for a total of 12–61% buffered streamsides (average?=?44%). Using multi-year water quality data collected before and after CREP implementation (1986, 2003–2006), we were unable to detect significant effects of CREP on baseflow nutrient concentrations based on the area of restored buffer, the percentage of restored streamside, or the percentage of total riparian buffer in the sub-basins (p?>?0.05). Although CREP increased the average buffered streamside from 33% in the 1990s to 44% by 2005, N and P concentrations have not changed or have increased in some streams over the last 20 years. Reductions may not have occurred for the following reasons: (1) buffer age, width, and connectivity (gaps) between buffers are also important to nutrient reductions; (2) agricultural nutrient inputs may have increased during this period; and (3) riparian buffer restoration was not extensive enough by 2005 to have measurable affects on the stream water quality in these sub-basins. Significant effects of CREP may yet be resolved as the current CREP buffers mature; however, water quality data through 2006 in the Choptank basin do not yet show any significant effects. 相似文献
13.
Anne E. Desjardins Mark Busman Michael Muhitch Robert H. Proctor 《Physiological and Molecular Plant Pathology》2007,70(4-6):149-160
Zea mays often is colonized with the fungus Gibberella moniliformis, which produces fumonisin toxins. The role of fumonisins in seedling colonization and blight was studied using complementary genetic analyses of host and pathogen. Only one of two fumonisin B1 (FB1)-insensitive maize backcross lines was more resistant than the FB1-sensitive parent to seedling blight, indicating that the increase in FB1-insensitivity was not associated with an increase in resistance. FB1-producing and nonproducing isogenic fungal strains did not differ in ability to cause seedling blight, but the FB1-producing strain was more effective in systemic colonization of seedlings in reciprocal strain challenge tests. Together, these and previous results indicate that the role of fumonisins depends on complex environmental and genetic contexts in this host–pathogen interaction. 相似文献
14.
Janne Salminen Anne Hernesmaa Heli Karjalainen Hannu Fritze Martin Romantschuk 《Biology and Fertility of Soils》2010,46(2):113-126
Soil faunal activity stimulates terrestrial carbon and nutrient cycling and maintains soil physical structure. Interestingly, the effects of faunal activity on soil microbial community composition and activity is less clear, although the microbial community evidently is the key element of terrestrial decomposition processes and nutrient cycling. We manipulated the composition of soil fauna in mesh bags with various mesh sizes (5, 45, and 1,000 µm) to exclude faunal groups based on body size. Our experiment indicated that feeding and foraging activity of nematodes and enchytraeids modified the physical–chemical properties of the soil and had long-term effects on soil bacterial community composition (measured by denaturing gel electrophoresis, colony-forming unit counts, and phospholipid fatty acid pattern). However, microbial enzyme (phosphomonoesterase, butyrate-esterase, ß-glucosidase, N-acetyl-glucosamidase, and ß-cellobiosidase) activities (measured by fluorogenic model substrates), decomposition rate of woody and cellulose material, or C and N status of the soil were not altered by the faunal treatment. Instead, enzyme activity was reduced by soil drying. Our results give support to ideas that functional redundancy is a common characteristic of the soil organisms, but no support was found for the idea that the community composition of soil decomposers had a strong link to the regulation of C and N cycles in the soil. 相似文献
15.
Paratuberculosis was diagnosed in a goat herd that participated in a sanitation program against Mycobacterium avium subsp. paratuberculosis. The aim of this study was to characterise the development of gamma interferon (IFN-γ) and antibody responses as well as the occurrence of faecal shedding. Faecal culture appeared surprisingly sensitive as about 18% and 40% of the goats were positive at 9 and 15-17 months of age, respectively, and shedding was often seen prior to peripheral immune responses. Peripheral IFN-γ responses were not related to protection as clinical and high shedding goats often had high responses. An IFN-γ response usually preceded a humoral response. However, positive antibody titers could sometimes be seen simultaneously with, and even prior to, IFN-γ responses. In conclusion, faecal culture appeared as sensitive as IFN-γ testing. Furthermore, the antibody ELISA and the IFN-γ assay may perform equally well in an infected herd if surveillance is conducted annually. 相似文献
16.
Summary S1 to S5 inbred lines, derived from a maize population bred for its overall resistance to three tropical viruses, were screened for resistance to maize streak virus (MSV) by artificial plant infection using viruliferous leafhoppers. Symptoms were rated and intra-line frequency distributions studied for all pedigree inbred lines. Mortality due to MSV was very low among these inbreds. Symptoms appeared later, developed slower and were less severe than in the susceptible control hybrid. Results of a study of 500 S1 and 93 S2 lines suggested that resistance is under genetic control via a system involving loci with major genes (with dominance for resistance) controlling high to complete resistance, associated with a genetic system involving loci with minor genes controlling partial resistance. Lines expressing complete resistance to MSV were developed from 5 cycles of inbreeding and selection. The relevance of such complete and partial resistance is discussed.Abbreviations MRPS
Mean Rating for Plants exhibiting Symptoms 相似文献
17.
Detection of Actinobacillus pleuropneumoniae Infection in Pigs 总被引:8,自引:1,他引:8
Willson PJ Falk G Klashinsky S 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(3):111-116
It is difficult to control the spread of porcine haemophilus pleuropneumonia caused by Actinobacillus pleuropneumoniae because there is no sensitive and specific way to accurately determine whether or not a pig herd is infected. This paper reports bacteriological and serological techniques used to detect A. pleuropneumoniae infection in pigs from a herd with endemic disease.
The bacteria were isolated from the anterior nasal mucosa of grower pigs, but not from younger or older pigs. Bacteriological culture of several tissues from the respiratory tract showed that nine of ten young finishing pigs were infected, but culture of lung tissue from slaughtered hogs detected infection in only 39 of 288 (13.5%). Both cooler storage temperature and use of selective medium prolonged the time that lung tissue could be stored and the organism still recovered. An enzyme-linked immunosorbent assay detected serotype-specific antibodies in serum of infected pigs.
相似文献18.
19.
Repeatability of fin length measurements using digital image analysis and studies of fin erosion as indicator of social interactions in Atlantic cod (Gadus morhua) 下载免费PDF全文
Yajing He Hanne Marie Nielsen Ingrid Olesen Jørgen Ødegård Børge Damsgård 《Aquaculture Research》2016,47(10):3180-3188
The aims of this study were to examine fin erosion caused by social interactions between Atlantic cod (Gadus morhua) juveniles, and to evaluate the repeatability of recorded fin length using digital image analysis (DIA). Fin length of 2100 juvenile Atlantic cod was analysed using DIA, during a 6 weeks experiment. The lengths of the three dorsal fins and the caudal fin were measured by three different assessors (M, K, B) three times during the experiment. Repeatability was based on a sub set of data from 42 randomly chosen fish. Assessor M measured the length of the fins of the 42 fish three times (M1, M2, M3). M1 and M2 were done on the same day, while M3 was conducted 2 weeks later. Assessor K measured two times with a 2‐year interval, and assessor B measured the fin length only once. The correlations between replicated measurements within assessor were highest for assessor M measured on the same day indicating an effect of memory. Repeatability of fin length ranged from 0.57 to 0.73 for the four fins. Social interaction with respect to fin erosion was studied using data on the four fins from all 2100 fish. ‘Relative fin length’ (fin length/total body length × 100) was calculated to assess fin erosion. Results indicated that all four fins were eroded due to social interactions, but the caudal fin was most severely eroded. In conclusion, DIA can be used to measured fin length but the method could be improved by using chromatic pictures. 相似文献
20.
Mayada Gwida Maged El-Ashker Falk Melzer Mohamed El-Diasty Mohamed El-Beskawy Heinrich Neubauer 《Irish veterinary journal》2015,69(1):3