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121.
The need to safely field test genetically modified organisms is a critical step in the sequence of research leading to the commercialization of biotechnology in agriculture. To address this need the United States Department of Agriculture has established the National Biological Impact Assessment Program (NBIAP) to facilitate the safe field testing of genetically modified organisms. NBIAP fosters safe field testing of genetically modified organisms through a computerized network for information exchange, facilitation of biological monitoring techniques and by providing support for research in biosafety to develop new field testing methods and better predictive models. 相似文献
122.
J Sun A Rojas P Bertrand Y Petit R Kraenzler PJ Arnoux 《Traffic injury prevention》2012,13(5):519-528
Objective: With 16 percent of the total road user fatalities, motorcyclists represent the second highest rate of road fatalities in France after car occupants. Regarding road accidents, a large proportion of trauma was on the lower cervical spine. According to different clinical studies, it is postulated that the cervical spine fragility areas are located on the upper and lower cervical spine. In motorcycle crashes, impact conditions occur on the head segment with various orientations and impact directions, leading to a combination of rotations and compression. Hence, motorcyclist vulnerability was investigated considering many impact conditions. Method: Using the human model for safety (HUMOS), a finite element model, this work aims to provide an evaluation of the cervical spine weaknesses based on an evaluation of injury mechanisms. This evaluation consisted of defining 2 injury risk factors (joint injury and bone fracture) using a design of experiment including various velocities, impact directions, and impact orientations. Results: The results confirmed previously reported clinical and epidemiological work on the fragility of the lower cervical spine and the upper cervical spine segments. Joint injuries appeared before bone fractures on both the upper and lower cervical spine. Bone fracture risk was greater on the lower cervical spine than on the upper cervical spine. The compression induced by a high impact angle was identified as an important injury severity factor. It significantly increased the injury incidence for both joint injuries and bone fractures. It also induced a shift in injury location from the lower to the upper cervical spine. The impact velocity exhibited a linear relationship with injury risks and severity. It also shifted the bone fracture risk from the lower to upper spinal segments. 相似文献
123.
Shih-Houng Young Jean M. Cox-Ganser Elizabeth S. Shogren Michael G. Wolfarth Shengqiao Li James M. Antonini 《毒物与环境化学》2013,95(4):806-823
It is observed that 1?→?3-β-glucan, a major cell wall component of fungi, induces pulmonary inflammation. There is inconsistency in determining the correlation between the levels of glucan measured by current extraction methods and the respiratory inflammation observed in individuals or lab animals exposed to environmental dust samples. The glucan-specific limulus amebocyte lysate (G-LAL) method was used after extraction with dimethyl sulfoxide (DMSO) or sodium hydroxide (NaOH) to analyze the glucan content of office dust samples collected from a water-damaged building. C3HeB/FeJ mice, an endotoxin-sensitive strain, were treated with different dust samples (2.5?mg?kg?1 body weight) or saline (vehicle control) by pharyngeal aspiration. At 1?day after aspiration, bronchoalveolar lavage (BAL) was performed, and lung inflammation and injury were assessed by measuring: (1) neutrophil (PMN) infiltration, (2) inflammatory cytokine (IL-6, IL-10, MCP-1, IFN-γ, TNF-α, and IL12-p70) levels, and (3) albumin and lactate dehydrogenase in recovered BAL fluid. Both DMSO and NaOH extraction increased the detection of glucan by approximately 20-fold compared to water extraction. However, only the DMSO extraction method showed a statistically significant positive correlation between 1?→?3-β-glucan and albumin levels, total numbers of BAL, polymorphonuclear leukocytes (PMNs) cells recovered, levels of TNF-α, MCP-1, and IL-6. In conclusion, 1?→?3-β-glucan is a potent inflammatory agent in dust samples and DMSO extraction for glucan analysis may prove useful in understanding the impact of environmental contamination by glucans on lung disease. 相似文献
124.
Jean Rouchaud Marc Metsue Fabrice Gustin Frans van de Steene Christian Pelerents Frans Benoit 《毒物与环境化学》2013,95(1-4):215-226
For the protection of early and summer cauliflower and brussels sprouts crops against root fly, the insecticide chlorpyrifos was applied at planting onto soil around the stem of the plant, or in the planting line. In the soil, chlorpyrifos (1) was transformed into the insecticide metabolites oxon, 0,0‐diethyl‐0‐(3,5,6‐tri‐chloro‐2‐pyridinyl) phosphate (2), and 3,5,6‐trichloro‐2‐pyridinol (3). The soil half life time of chlorpyrifos could be 2.8 times greater (42 days relative to 15 days) when the field history as to cauliflower monoculture and insecticide treatments was short (1 year), than when it was long (8 years). Rains and season also had cumulative effects on the chlorpyrifos soil half life times. In the leaves of cabbage, chlorpyrifos and compound 3 were observed at concentrations which were higher, especially when their soil concentrations were high. Chlorpyrifos and compounds 2 and 3 however were not detected in the “flower” of cauliflower, nor in the brussels sprouts itself, the limit of sensitivity being 0.02 ppm of fresh weight. 相似文献
125.
Sophie Arnaud-Haond V. Vonau C. Rouxel F. Bonhomme Jean Prou E. Goyard P. Boudry 《Marine Biology》2008,155(2):147-157
In order to study further the genetic structure of the pearl oyster Pinctada margaritifera in French Polynesia with a special consideration for the sampling scale, we analyzed or re-analyzed sets of data based on
nuclear DNA markers obtained at different spatial scales. At a large scale (several 1,000 km), the remote Marquesas Islands
were confirmed to be significantly differentiated from Tuamotu–Gambier and Society archipelagos, with a marked difference
however for the two main islands that are different from each other. At a medium scale (several 10 to several 100 km), overall
homogeneity was observed within and between these two archipelagos, with some exceptions. This could be attributed both to
large-scale larval dispersal and to human-driven spat translocations due to pearl oyster cultivation. These results contrast
with those observed (1) at a small scale (less than 10 km) in a lagoon heavily impacted by translocation and cultural practices,
where significant genetic differentiation was detected among three laying beds, and (2) at a micro scale where we detected
an important variability of the genetic composition of young spat recruited on artificial collectors. Such patterns could
result from a high variance in the number of genitors at the origin of each cohort, or from pre- or post-settlement selection
on linked loci. Altogether, our data support the hypothesis that under certain conditions populations of bivalves may exhibit
patterns of chaotic genetic patchiness at local scale, in line with the increasing report of such patchiness in marine benthic
organisms. This underlines the importance of sampling scale that should be rigorously defined depending on the questions to
be answered. Nevertheless, a survey of about 80 articles dealing with population genetics of marine invertebrates showed that
only 35% of those studies disclosed details about the sampling strategy (particularly the area explored). These results emphasize
the need for cautious interpretation of patterns of genetic structure at medium scale when rigorous sampling strategies are
not deployed.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
126.
Roger L. Hothem David G. Lonzarich Jean E. Takewaka Harry M. Ohlendorf 《Environmental monitoring and assessment》1998,50(1):67-84
Organochlorines, metals, and trace elements were measured in liver, kidney, or whole-body tissues of canvasbacks (Aythya valisineria), lesser scaups (A. affinis), and greater scaups (A. marila) collected from San Francisco Bay and three coastal areas of California during the winter of 1986–1987. Potentially toxic concentrations of mercury (mean 10.4 µg/g, dry weight) and selenium (mean 32.7 µg/g, dry weight) were found in livers of scaups and canvasbacks from several San Francisco Bay sites. These elements varied spatially, temporally, and between species, with the highest concentrations found in late winter. Mean concentrations of mercury, selenium, and cadmium were generally higher in scaups than in canvasbacks. Of all the organochlorines included in the analyses, only p,p'-DDE and total PCBs were detected in all samples in this study. Mean whole-body concentrations of DDE and PCBs from San Francisco Bay ducks collected in late winter varied spatially and between species, but the concentrations were not considered toxic. Causes for inter-specific differences are unclear, but may be attributable to differences in diet, movement, or physiology. 相似文献
127.
128.
129.
Anne-Catherine Bénard Vincent Darcos Christian Drakides Claude Casellas Jean Coudane Michel Vert 《Journal of Polymers and the Environment》2011,19(1):40-48
Water-soluble synthetic polymers are extensively used in cosmetics, detergents and paints. Many end up in wastewater and,
later on, in wastewater-treatment plants. In order to gain an insight into their fate in such plants, fluorescence and radioactivity
labelings were compared using a lab-scale reactor designed to mimic industrial conditions. Two fermentation media were considered,
namely a mixture of E402 and E204 micro-organisms and an activated sludge collected from a water-treatment plant located in
the south of France. A sample of low molar mass commercial poly(acrylic acid) (PAA) was labeled by radioactivity with tritium
and by coupling the 6-aminofluorescein fluorescent dye. Labeled PAA-containing sludges were allowed to ferment. To monitor
the fate of the polymers, aliquots of the fermented mixtures were withdrawn at selected times and centrifuged. Liquid and
solid phases were analyzed by scintigraphy or UV spectrometry, depending of the labeling techniques. Both techniques led to
similar distributions, c.a. 75% in the supernatant and 25% in the solid phase. Distributions remained constant during the
biological tests. There was no degradation of the commercial PAA after aqueous size exclusion chromatography (SEC), in agreement
with literature. These features showed that fluorescence-labeling can be used instead of the complex and expensive radiolabeling.
The validated fluorescence-based method was then applied to a linear poly(acrylic acid) synthesized by ATRP and labeled with
6-aminofluorescein. There was no significant difference between the commercial and the linear poly(acrylic acid)s. In contrast,
a linear PAA with 5% of tert-butyl ester repeating units was predominantly found in the solid phase although adsorption or absorption by micro-organisms
could not be demonstrated. The method based on fluorescence labeling should be applicable to other water soluble polymers
provided that the dye remains attached to the polymer as it was the case for the studied poly(acrylic acid)s. 相似文献
130.
Jérôme Buhl Jean Louis Deneubourg Anne Grimal Guy Theraulaz 《Behavioral ecology and sociobiology》2005,58(1):9-17
Many ant species adjust the volume of their underground nest to the colony size. We studied whether the regulation of the volume of excavated sand could result from an interplay between recruitment processes and ant density. Experiments were performed with different group sizes of workers in the ant Messor sancta. When presented with a thin homogeneous sand disk, these groups excavated networks of galleries in less than 3 days. The excavation dynamics were logistic shaped, which suggests the existence of a double feedback system: a positive one resulting in an initial exponential growth phase, and a negative one leading the dynamics to a saturation phase. The total volume of excavated sand was almost proportional to the number of workers. We then developed a model in which we incorporated the quantitative behavioral rules of the workers digging activity. A positive feedback was introduced in the form of a recruitment process mediated by pheromones. The model predicts that the excavation dynamics should be logistic shaped and the excavation should almost stop despite the absence of any explicit negative feedback. Moreover, the model was able to reproduce the positive linear relationship between nest volume and colony size.Communicated by K. Ross 相似文献