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31.
Bioavailability of triazine herbicides in a sandy soil profile 总被引：1，自引：0，他引：1
Carsten S. Jacobsen Nir Shapir Lene O. Jensen Einar H. Jensen Réne K. Juhler Jens C. Streibig Ralphi T. Mandelbaum Arne Helweg 《Biology and Fertility of Soils》2001,33(6):501-506
The bioavailability of atrazine was evaluated in a Danish soil profile (Drengsted) using a combination of soil sorption, transport and mineralisation methods as well as inoculation using Pseudomonas ADP. Sorption of atrazine decreased markedly with depth as indicated by Kd values of 5.2 l kg-1 for the upper soil and 0.1 l kg-1 for the subsoils. The transport of atrazine was evaluated using soil TLC plates and the resulting Rf values were 0.1 for the upper soil and 0.9 for the subsoil. Only a relatively small amount of atrazine leached through undisturbed soil columns taken from the upper 60 cm. Inoculating with Pseudomonas strain ADP (1᎒6 CFU g-1 dry weight soil) revealed that the degradation of 0.01 ppm atrazine was fully completed (80% mineralisation) within 10 days in the subsoil, while it reached less than 15% in the upper soil. Over a period of 500 days, a total mineralisation of 37% of added atrazine in the upper soil was found (2 mg kg-1 incubated at 20° C). However, in the subsurface soil where 0.02 mg kg-1 of atrazine was incubated at 10°C, the degradation was slower, only reaching about 12%. Terbuthylazine mineralisation was found to be temperature-dependent and low (less than 5%) in the upper soil and very much lower in the subsoil. Desethylterbuthylazine was the most frequently found metabolite. Finally, Pseudomonas strain ADP inoculated into soils from different depths increased the mineralisation of terbuthylazine dramatically. Modelling using a "two-compartment model" indicated that desorption of terbuthylazine is the limiting step for its mineralisation. 相似文献
32.
Clare Greathead Paolo Magni Jan Vanaverbeke Lene Buhl‐Mortensen Urszula Janas Mats Blomqvist Johan A. Craeymeersch Jennifer Dannheim Alexander Darr Steven Degraer Nicolas Desroy Annick Donnay Yessica Griffiths Ivan Guala Laurent Guerin Hayley Hinchen Celine Labrune Henning Reiss Gert Van Hoey Silvana N.R. Birchenough 《水产资源保护:海洋与淡水生态系统》2020,30(7):1253-1275
- There is concern across the International Council for the Exploration of the Sea (ICES) region that a consideration of vulnerable components and the wider support mechanisms underpinning benthic marine ecosystems may be lacking from the process of marine protected area (MPA) designation, management and monitoring.
- In this study, MPAs across six European ecoregions were assessed from a benthic ecology perspective. The study included 102 MPAs, designated by 10 countries, and focused on three aspects regarding the role of the benthos in: (i) the designation of MPAs; (ii) the management measures used in MPAs; and (iii) the monitoring and assessment of MPAs.
- Qualitative entries to a questionnaire based on an existing framework (EU project ‘Monitoring Evaluation of Spatially Managed Areas’, (MESMA) were collected by 19 benthic experts of the ICES Benthic Ecology Working Group. A pedigree matrix was used to apply a numerical scale (score) to these entries.
- The results showed clear differences in scores between ecoregions and between criteria. The designation‐phase criteria generally achieved higher scores than the implementation‐phase criteria. Poor designation‐phase scores were generally reiterated in the implementation‐phase scores, such as scores for assessment and monitoring.
- Over 70% of the MPA case studies were found to consider the benthos to some extent during selection and designation; however, this was not followed up with appropriate management measures and good practice during the implementation phase.
- Poor spatial and temporal coverage of monitoring and ineffective indicators is unlikely to pick up changes caused by management measures in the MPA. There is concern that without adequate monitoring and adaptive management frameworks, the MPAs will be compromised. Also, there could be an increased likelihood that, with regard to the benthos, they will fail to meet their conservation objectives.
- This assessment was successful in highlighting issues related to the representation and protection of the benthos in MPAs and where changes need to be made, such as expanding the characterization and monitoring of benthic species or habitats of interest. These issues could be attributable to an ongoing process and/or an indication that some MPAs only have ‘paper protection’.
33.
Peter M Raundal Pia H Andersen Nils Toft Björn Forkman Lene Munksgaard Mette S Herskin 《Veterinary anaesthesia and analgesia》2014,41(6):660-669
ObjectiveTo examine the use of handheld methodology to assess mechanical nociceptive threshold (MNT) on cows kept loose-housed.Study designProspective randomized partial cross-over experimental study. A one-factor (test day) design was used to evaluate MNT over time.AnimalsOne hundred and fifteen healthy, loose-housed Danish Holstein cattle.MethodsWe evaluated intra-individual variation, inter-observer agreement and variation over time of MNT using two handheld devices and two stimulation sites. Mechanical, ramped stimulations were performed with an algometer (6.5 mm diameter steel probe, 0–10.0 kgf) or an electronic von Frey device (plastic tip with diameter 0.8 mm, 0–1000 gf). Each cow received 5–6 consecutive stimulations within a 2 × 5 cm skin area on the dorsal or lateral aspect of the left third metatarsus until an avoidance reaction occurred. We investigated the difference in precision [expressed as coefficient of variation (CV)] between the combinations of devices and stimulation sites. The inter-observer agreement and the difference in MNT between test day 1, 3, 7, 10 and 24 were investigated for selected combinations. Data were analysed in mixed models and Bland-Altman as relevant.ResultsThe CVs did not differ [range 0.34–0.52 (p = 0.1)]. Difference between observers (95% limits) was 0.2 kgf (2.8) and 4 gf (369) for the algometer and von Frey device, respectively. Mechanical nociceptive threshold increased from 361 on test day one to 495 gf on test day 24 (p < 0.01).Conclusion and clinical relevanceAll methods showed a high degree of intra-individual variation, and no combination of device and stimulation site showed superior precision. Mean difference between observers was low, and MNT was not consistent over time. Further development of the methods is required before they can be used in research to investigate possible relations between claw lesions and hyperalgesia. 相似文献
34.
Rheological properties of gluten from three biscuit wheat cultivars (Triticum aestivum, L., cv. Reaper, Ritmo, Encore) were studied. The cultivars were grown in two seasons (1997–1999) with three different nitrogen levels, and nitrogen fertiliser was applied using three different strategies. Protein and gluten contents were significantly affected by the N level (P<0.001), but inter-cultivar differences were only significant in 1999, when growing conditions were restricted by environmental factors. The viscoelastic properties of gluten were characterised by creep recovery and oscillation testing. The results showed a significant inter-cultivar effect (P<0.001), with an additional effect from the N level (P<0.001). Increasing levels of nitrogen fertiliser increased the viscous properties of gluten, through an increase of maximum strain and recovery strain, and through a decrease of the storage (G′) and loss modulus (G′′), whereas the phase angle, δ, increased. This increase in viscous behaviour is suggested to be attributed to a higher gliadin/glutenin ratio in the gluten. The fertiliser application strategy did not influence the rheological properties significantly. Thus, high N fertiliser application in biscuit wheat cultivation may be beneficial to obtain rheological properties, which are suitable for biscuit making. 相似文献
35.
Summary Texture of boiled potato tubers (cv. Beate) was studied over several months of storage at either 4 or 8 °C, in relation to
dry matter content, non-starch polysaccharides (NSP), methyl groups, glucose, starch and amylose. The dry matter content decreased
significantly during storage at 4 °C, but increased at 8 °C due to evaporation. The insoluble NSP contained rhamnose, galactose,
arabinose, xylose, mannose, fucose and glucose; the first three sugars decreased significantly after the first 7 weeks of
storage. Fracturability and percent compression before break increased during storage at 8 °C, particularly percent compression
after 15 weeks. The change in fracturability could partly be explained (R2=43.4%) by the content of the NSP and the increase in percent compression by dry matter (R2=91.8%). Changes in texture during storage at 4 °C, however, were not striking, and could not be explained by changes in the
potato components that were analysed. 相似文献
36.
Summary Potato leafroll virus and potato viruses M, S, X and Y in green leaves were detected by dot immunobinding (DIB) on plain paper
and on nitrocellulose membranes. On both materials, DIB could detect the presence of very small amounts of virus, e.g. 30
pg of purified PVX. The sensitivity of the DIB test on plain paper and on nitrocellulose was compared to Double Antibody Sandwich
ELISA (DAS-ELISA) by serial dilutions of infected plant sap made in healthy plant sap. Detection of potato viruses by DIB
on plain paper and nitrocellulose was found to be equally sensitive whereas DAS-ELISA was 2 to 8 times more sensitive. Possible
simplifications of the DIB procedure to suit the requirements of a routine method were examined. The use of the DIB method
for routine testing of potato viruses is discussed. 相似文献
37.
Søren Borg Henrik Brinch-Pedersen Birgitte Tauris Lene Heegaard Madsen Behrooz Darbani Shahin Noeparvar Preben Bach Holm 《Journal of Cereal Science》2012
The characterization of the full complement of wheat ferritins show that the modern hexaploid wheat genome contains two ferritin genes, TaFer1 and TaFer2, each represented by three homeoalleles and placed on chromosome 5 and 4, respectively. The two genes are differentially regulated and expressed. The TaFer1 genes are, except in the endosperm, the most abundantly expressed and regulated by iron and abscisic acid status. The promoter of TaFer1, in contrast to TaFer2, has iron- and ABA-responsive elements, supporting the expression data. The TaFer1 and TaFer2 genes encode two isoforms, probably functional different and acting in heteropolymer structures of ferritin in cereals. Iron biofortification of the wheat grain is possible. Endosperm targeted intragenic overexpressing of the TaFer1-A gene results in a 50–85% higher iron content in the grain. 相似文献
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39.
Boysen L Serup J Sørensen P Kristensen F 《American journal of veterinary research》2002,63(4):559-564
OBJECTIVE: To evaluate whether skin erythema in clinically normal dogs can be quantified by use of chromametry and image analysis of digital photographs. ANIMALS: 9 German Shepherd Dogs and 10 mixed-breed dogs. PROCEDURE: Hair was clipped at 7 sites on the body. Skin erythema was evaluated at the axillary region, right and left lateral aspect of thorax, right and left loin area (ie, part of the back between the thorax and pelvis), right and left groin area (ie, the junctional region between the abdomen and thigh), metatarsal digital pad, and on the nose. Replicate measurements were done by use of chromametry and image analysis of digital photographs, using erythema values in accordance with the Committee International d'Eclairage (CIE)-Lab color system. RESULTS: Repeatability was high for both techniques. Within-dog variation was lower than between-dog variation. Between-dog variation was high for both groups of dogs. Interregional variation was significant in German Shepherd Dogs and mixed-breed dogs. Erythema values revealed symmetry between the right and left lateral aspects of the thorax and loin and groin areas. CONCLUSIONS AND CLINICAL RELEVANCE: Precise objective methods are available for skin erythema quantification. Chromametric and photographic erythema values had a high within-dog reproducibility. Between-dog variability was high for German Shepherd Dogs and mixed-breed dogs as was regional variation, indicating differences in color among dogs. 相似文献
40.
Boysen L Sørensen P Larsen M Serup J Kristensen F 《American journal of veterinary research》2002,63(4):565-569
OBJECTIVE: To investigate whether the degree of erythema during an induced erythematous reaction, the histamine skin test reaction, can be assessed objectively by use of chromametry and image analysis of digital photographs. ANIMALS: 9 pet dogs (6 Golden Retrievers and 3 yellow Labrador Retrievers). PROCEDURE: Histamine phosphate was injected intradermally, and erythema of the wheal reaction was evaluated during the hour that followed. This was done by use of clinical scores, chromametry, and image analysis of digital photographs. Method reproducibility was tested for visual evaluation of printouts of digital photographs and for image analysis of the same photographs. RESULTS: The coefficient of variation of the technically derived erythema values was < 10%. The reproducibility of image analysis was high and the range of agreement between observers narrow. Using chromametry, it was not possible to differentiate between various degrees of erythema intensity as visually perceived. In contrast, use of image analysis of digital photographs enabled discrimination of slight erythema from moderate and marked erythema. The dynamics of reaction measured by chromametry followed the clinical observation. CONCLUSIONS AND CLINICAL RELEVANCE: Chromametric values are comparable to those obtained by visual inspection. As the result of standardized conditions, chromametry is preferred over digital photography. 相似文献