排序方式： 共有29条查询结果，搜索用时 437 毫秒
11.
S Houweling B Badawy DF Baker S Basu D Belikov P Bergamaschi P Bousquet G Broquet T Butler JG Canadell J Chen F Chevallier P Ciais GJ Collatz S Denning R Engelen IG Enting ML Fischer A Fraser C Gerbig M Gloor AR Jacobson DB Jones M Heimann A Khalil T Kaminski PS Kasibhatla NY Krakauer M Krol T Maki S Maksyutov A Manning A Meesters JB Miller PI Palmer P Patra W Peters P Peylin Z Poussi MJ Prather JT Randerson T Röckmann C Rödenbeck JL Sarmiento DS Schimel M Scholze A Schuh P Suntharalingam 《Science (New York, N.Y.)》2012,337(6098):1038-1040
12.
Reduction of pesticide residues on produce by rinsing 总被引：6，自引：0，他引：6
Krol WJ Arsenault TL Pylypiw HM Incorvia Mattina MJ 《Journal of agricultural and food chemistry》2000,48(10):4666-4670
In 1997 this laboratory initiated a research program with the objective of examining the effect that rinsing of produce with tap water would have on pesticide residues. Samples were obtained from local markets and/or grown at our experimental farm. Because approximately 35% of produce from retail sources contains pesticide residues, growing and treating produce at an experimental farm had the advantage that all such samples contain pesticide residues. Pesticides were applied under normal field conditions to a variety of food crops and the vegetation was allowed to undergo natural weathering prior to harvest. The resulting samples contained field-incurred or "field-fortified" residues. This experimental design was employed to mimic as closely as possible real world samples. Crops were treated, harvested, and divided into equal subsamples. One subsample was processed unwashed, whereas the other was rinsed under tap water. The extraction and analysis method used was a multi-residue method developed in our laboratory. Twelve pesticides were included in this study: the fungicides captan, chlorothalonil, iprodione, and vinclozolin; and the insecticides endosulfan, permethrin, methoxychlor, malathion, diazinon, chlorpyrifos, bifenthrin, and DDE (a soil metabolite of DDT). Statistical analysis of the data using the Wilcoxon signed-rank test showed that rinsing removed residues for nine of the twelve pesticides studied. Residues of vinclozolin, bifenthrin, and chlorpyrifos were not reduced. The rinsability of a pesticide is not correlated with its water solubility. 相似文献
13.
This paper presents one of the first integrated analyses of acidification and climate change on a geographically-detailed basis, and the first linkage of integrated models for acid deposition (RAINS) and for climate change (IMAGE 2). Emphasis in this paper is on Europe. Trends in driving forces of emissions are used to compute anthropogenic SO2 emissions in 13 world regions. These emissions are translated into regional patterns of sulfur deposition in Europe and global patterns of sulfate aerosols using source-receptor matrices. Changes in climate are then computed based on changes in sulfate and greenhouse gases. Finally, we compute ecosystem areas affected by acid deposition and climate change based on exceedances of critical loads and changes in potential vegetation. Using this framework, information from global and regional integrated models can be used to link sulfur emissions with both their global and regional consequences. Preliminary calculations indicate that the size of European area affected by climate change in 2100 (58%) will be about the same as that affected by acid deposition in 1990. By the mid 21st century, about 14% of Europe's area may be affected by both acid deposition and climate change. Also, reducing sulfur emissions in Europe will have both the desirable impact of reducing the area affected by acid deposition, and the undesirable impact of enhancing climate warming in Europe and thus increasing the area affected by climate change. However, for the scenarios in this paper, the desirable impact of reducing sulfur emissions greatly outweighs its undesirable impact. 相似文献
14.
15.
Andrzej?G.?GórnyEmail author Zofia?Banaszak Bogumila??ugowska Dominika?Ratajczak 《Euphytica》2011,177(2):191-206
The effects of contrasting soil nitrogen (N) levels on the inheritance of the efficiency of N uptake and N utilization in
grain mass formation were examined in winter wheat. Parents of various origins and their diallel F2-hybrids were evaluated in field and pot experiments under varying levels of soil N. The range of additive variance in the
components of N efficiency was narrow, especially under N shortage. The soil N-treatments imposed had a substantial influence
on gene actions responsible for the efficiency components and modes of inheritance. Genotype × nutrition interactions were
common. Under high N-fertilization, the efficiency components were inherited in a manner favourable for wheat selection (preponderance
of additive effects). However, the enhanced contribution of non-additive gene effects and increased dominance under N-limited
conditions could impede wheat selection to improve the N efficiency and adaptation to less luxurious fertilization regimes.
Selection methods that eliminate masking non-additive influences and take advantage of the additive variance should be employed
to improve these traits. 相似文献
16.
ABSTRACT: BACKGROUND: Quantification of leaf movement is an important tool for characterising the effects of environmental signals and the circadian clock on plant development. Analysis of leaf movement is currently restricted by the attachment of sensors to the plant or depended on visible light for time-lapse photography. The study of leaf growth movement rhythms in mature plants under biological relevant conditions, e.g. diurnal light and dark conditions, is therefore problematic. RESULTS: Here we present OSCILLATOR, an affordable system for the analysis of rhythmic leaf growth movement in mature plants. The system contains three modules: (1) Infrared time-lapse imaging of growing mature plants (2) measurement of projected distances between leaf tip and plant apex (leaf tip tracking growth-curves) and (3) extraction of phase, period and amplitude of leaf growth oscillations using wavelet analysis. A proof-of-principle is provided by characterising parameters of rhythmic leaf growth movement of different Arabidopsis thaliana accessions as well as of Petunia hybrida and Solanum lycopersicum plants under diurnal conditions. The amplitude of leaf oscillations correlated to published data on leaf angles, while amplitude and leaf length did not correlate, suggesting a distinct leaf growth profile for each accession. Arabidopsis mutant accession Landsberg erecta displayed a late phase (timing of peak oscillation) compared to other accessions and this trait appears unrelated to the ERECTA locus. CONCLUSIONS: OSCILLATOR is a low cost and easy to implement system that can accurately and reproducibly quantify rhythmic growth of mature plants for different species under diurnal light/dark cycling. 相似文献
17.
18.
Robin M. Overstreet Kenneth C. Stuck Rena A. Krol William E. Hawkins 《Journal of the World Aquaculture Society》1988,19(4):175-187
Infections of the virus Baculovirus penaei (BP) have historically impacted penaeid shrimp production in both hatcheries and ponds. BP causes cytopathological alterations and mortality in at least four species, including Penueus vannamei . This study established experimental infections with BP in laboratory-reared P. vannamei . The most useful protocol involved BP infection in third substage protozoea (P3 ) induced by feeding virus-contaminated material to rotifers and, in turn, feeding those rotifers to the shrimp larva. Infections were also established by delivering virus-containing brine shrimp to mysis (M) and postlarval (PL) stages. When virus originating from infected adults and juveniles was fed to P3 's, the shrimp exhibited patent infections with hypertrophic nuclei, polyhedra, free virions, and occluded virions five or six days after being fed the virus. In contrast, when the source of virus material was from bioassay larvae rather than from adults and juveniles, similar patent infections developed in P3 's by one to two days. A significant mortality in the resulting M's and PL's was associated with the infections with short but not long prepatent periods. In experimentally infected shrimp, examination by light microscopy and transmission electron microscopy revealed extensive viral infection in many cells in the anterior midgut and as many as 80–90% of the proximal and medial hepatopancreatic tubular cells. Free and occluded virions capable of producing disease ruptured into the gut lumen soon after infections became patent. Tests conducted in 1 L Imhoff cones, 160 L spat-cones, and aquaria all produced infections, usually with a prevalence of 100%. The system provides a useful method to detect and assay for infective agents, to amass infective material for research purposes, and to assess the biology of and host response to the virus under different conditions. 相似文献
19.
Modulation of ruminal and intestinal fermentation by medicinal plants and zinc from different sources 
下载免费PDF全文
下载免费PDF全文 Zora Váradyová Dominika Mravčáková Monika Holodová Ľubomira Grešáková Jana Pisarčíková Marcin Barszcz Marcin Taciak Anna Tuśnio Svetlana Kišidayová Klaudia Čobanová 《Journal of animal physiology and animal nutrition》2018,102(5):1131-1145
Two experiments were conducted on sheep to determine the effect of dietary supplementation with zinc and a medicinal plant mixture on haematological parameters and microbial activity in the rumen and large intestine. In Experiment 1, 24 male lambs were randomly divided into four groups: One group was fed an unsupplemented basal diet (control), and three groups were fed a diet supplemented with 70 mg Zn/kg diet in the form of Zn sulphate (ZnSO4), a Zn‐chelate of glycine hydrate (Zn‐Gly) or a Zn‐proteinate (Zn‐Pro), for five months. The ruminal content was collected separately from each lamb, and batch cultures of ruminal fluid were incubated in vitro with mixture of medicinal plants (Mix) with different roughage:concentrate ratios (800:200 and 400:600, w/w). Bioactive compounds in Mix were quantified by UPLC/MS/MS. In Experiment 2, four sheep were fed a diet consisting of meadow hay and barley grain (400:600, w/w), with Zn‐Gly (70 mg Zn/kg diet), Mix (10% replacement of meadow hay) or Zn‐Gly and Mix (Zn‐Gly‐Mix) as supplements in a Latin square design. Mix decreased total gas (p < 0.001) and methane (p < 0.01) production in vitro. In Experiment 1, caecal isobutyrate and isovalerate concentrations varied among the dietary treatments (p < 0.01). The isovalerate concentration of the zinc‐supplemented groups in the distal colon was higher (p < 0.001) compared with the control. In Experiment 2, the molar proportion of isobutyrate was the highest in the faeces of the sheep fed the diet with Zn‐Gly‐Mix (p < 0.01). The plasma zinc concentration was higher in the groups fed a diet supplemented with zinc (p < 0.001). The haematological profile and antioxidant status did not differ between the dietary groups (p > 0.05). The diets containing medicinal plants and organic zinc thus helped to modulate the characteristics of fermentation in ruminants. 相似文献