Dissipation rates in soil of 1,2-dichloropropane and 1,3- and 2,3-dichloropropenes     

Hendrik van Dijk 《Pest management science》1980,11(6):625-632

The rates of dissipation in soil and chloride-ion release, of the main components of dichloropropane-dichloropropene mixtures used as nematicides, were studied in sealed glass containers at different temperatures and moisture conditions. Half-lives of (Z)- and (E)-1,3-dichloropropenes at 20°C in soils were found to vary from 3 to 25 days; those of 1,2-dichloropropane and 2,3-dichloropropene were about four times and twice as long, respectively. The dissipation rates changed by a factor of about 2 per 10°C change in temperature. Judging from the release rates of waterextractable inorganic chloride in the soil (0-4% per week), the total degradation of all components applied at normal field rates was extremely slow. This indicated the formation of residues containing covalently bound chlorine. Only in ‘enrichment cultures’ was complete degradation indicated.  相似文献   

Modeling climate change effects on the potential production of French plains forests at the sub-regional level   总被引：1，自引：0，他引：1  

Loustau D  Bosc A  Colin A  Ogée J  Davi H  François C  Dufrêne E  Déqué M  Cloppet E  Arrouays D  Le Bas C  Saby N  Pignard G  Hamza N  Granier A  Bréda N  Ciais P  Viovy N  Delage F 《Tree physiology》2005,25(7):813-823

We modeled the effects of climate change and two forest management scenarios on wood production and forest carbon balance in French forests using process-based models of forest growth. We combined data from the national forest inventory and soil network survey, which were aggregated over a 50 x 50-km grid, i.e., the spatial resolution of the climate scenario data. We predicted and analyzed the climate impact on potential forest production over the period 1960-2100. All models predicted a slight increase in potential forest yield until 2030-2050, followed by a plateau or a decline around 2070-2100, with overall, a greater increase in yield in northern France than in the south. Gross and net primary productivities were more negatively affected by soil water and atmospheric water vapor saturation deficits in western France because of a more pronounced shift in seasonal rainfall from summer to winter. The rotation-averaged values of carbon flux and production for different forest management options were estimated during four years (1980, 2015, 2045 and 2080). Predictions were made using a two-dimensional matrix covering the range of local soil and climate conditions. The changes in ecosystem fluxes and forest production were explained by the counterbalancing effect of rising CO2 concentration and increasing water deficit. The effect of climate change decreased with rotation length from short rotations with high production rates and low standing biomasses to long rotations with low productivities and greater standing biomasses. Climate effects on productivity, both negative and positive, were greatest on high fertility sites. Forest productivity in northern France was enhanced by climate change, increasingly from west to east, whereas in the southwestern Atlantic region, productivity was reduced by climate change to an increasing degree from west to east.  相似文献   

Design,synthesis and screening of herbicidal activity for new phenyl pyrazole-based protoporphyrinogen oxidase-inhibitors (PPO) overcoming resistance issues     

Rebecca L. Mattison  Roland Beffa  Guido Bojack  Birgit Bollenbach-Wahl  Christine Dörnbrack  Nicole Dorn  Jörg Freigang  Elmar Gatzweiler  Rahel Getachew  Claudia Hartfiel  Ines Heinemann  Hendrik Helmke  Sabine Hohmann  Harald Jakobi  Gudrun Lange  Peter Lümmen  Lothar Willms  Jens Frackenpohl 《Pest management science》2023,79(6):2264-2280

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Prognostic importance of plasma total magnesium in a cohort of cats with azotemic chronic kidney disease          下载免费PDF全文

D. Hendrik N. van den Broek  Yu‐Mei Chang  Jonathan Elliott  Rosanne E. Jepson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(4):1359-1371

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Contact structure and potential risk factors for avian influenza transmission among open-sided chicken farms in Kamalia, an important poultry rearing area of Pakistan     

Abbas T  Wilking H  Höreth-Böntgen D  Conraths FJ 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(3-4):110-116

Since 1994, the domestic poultry in Pakistan has experienced several outbreaks due to avian influenza viruses of subtypes H7N3, H5N1, and H9N2. This paper reveals horizontal contacts and potential risk factors for the spread of avian influenza infection between open-sided chicken farms in Kamalia, a sub-district of Punjab province. Between April and June 2009, an interview-based questionnaire was administered to a sample of 78 growers. The survey identified the following potential biosecurity risks for outbreak propagation: i) short buffer distances between farms, ii) disposal of carcasses and other organic wastes into the environment, iii) entry of feral birds into poultry sheds, iv) visits of poultry farmers to possible cross-contamination sites, v) absence of boundary walls, vi) incomplete biosecurity on high-risk visitors (i. e. those going inside the poultry houses), essential vehicles and equipment used by vaccination crews vii) visits of intermediaries and service providers and, viii) sharing of egg trays between farms at production. For most of the variables, there was no significant difference between the broiler and layer type of farms (p < or = 0.05). The risk of an extensive outbreak in Kamalia was concluded to be due to its high poultry density, ubiquitous small-scale, market-oriented poultry production with medium to low biosecurity, and the affiliation of the farmers to multiple service providers. To reduce the risk of having an outbreak, farm-specific biosecurity gaps should be identified and appropriate action taken to close these gaps. Improvement in biosecurity and targeted surveillance are therefore considered critical to limit the spread of infection should an outbreak occur.  相似文献   

Regional crop modelling in Europe: The impact of climatic conditions and farm characteristics on maize yields   总被引：1，自引：0，他引：1  

Pytrik Reidsma  Frank Ewert  Hendrik Boogaard  Kees van Diepen 《Agricultural Systems》2009,100(1-3):51-60

Impacts of climate variability and climate change on regional crop yields are commonly assessed using process-based crop models. These models, however, simulate potential and water limited yields, which do not always relate to observed yields. The latter are largely influenced by crop management, which varies by farm and region. Data on specific management strategies may be obtained at the field level, but at the regional level information about the diversity in management strategies is rarely available and difficult to be considered adequately in process-based crop models. Alternatively, understanding the factors influencing management may provide helpful information to improve simulations at the regional level.In this study, we aim to identify factors at the regional level that explain differences between observed and simulated yields. Observed yield data were provided by the Farm Accountancy Data Network (FADN) and Eurostat. The Crop Growth Monitoring System (CGMS), based on the WOFOST model, was used to simulate potential and water limited maize yields in the EU15 (i.e., the old member states of the European Union). Differences between observed and simulated maize yields were analysed using regression models including: (i) climatic factors (temperature and precipitation), (ii) farm size, (iii) farm intensity, (iv) land use, (v) income and (vi) subsidies. We assumed that the highest yields observed in a region were close to the yield potential as determined by climate and considered the average regional yields as also influenced by management. Model performance was analysed with respect to spatial and temporal yield variability.Results indicate that for potential yield, the model performed unsatisfactory in southern regions, where high temperatures increased observed yields which was in contrast to model simulations. When considering management effects, we find that especially irrigation and the maize area explain much of the differences between observed and simulated yields across regions. Simulations of temporal yield variability also diverted from observed data of which about 80% could be explained by the climatic factors (35%) and farm characteristics (50%) considered in the analysis. However, effects of specific factors differed depending on the regions. Accordingly, we propose different groups of regions with factors related to management which should be considered to improve regional yield simulations with CGMS.  相似文献   

Ancient biomolecules from deep ice cores reveal a forested southern Greenland   总被引：2，自引：0，他引：2  

Willerslev E  Cappellini E  Boomsma W  Nielsen R  Hebsgaard MB  Brand TB  Hofreiter M  Bunce M  Poinar HN  Dahl-Jensen D  Johnsen S  Steffensen JP  Bennike O  Schwenninger JL  Nathan R  Armitage S  de Hoog CJ  Alfimov V  Christl M  Beer J  Muscheler R  Barker J  Sharp M  Penkman KE  Haile J  Taberlet P  Gilbert MT  Casoli A  Campani E  Collins MJ 《Science (New York, N.Y.)》2007,317(5834):111-114

It is difficult to obtain fossil data from the 10% of Earth's terrestrial surface that is covered by thick glaciers and ice sheets, and hence, knowledge of the paleoenvironments of these regions has remained limited. We show that DNA and amino acids from buried organisms can be recovered from the basal sections of deep ice cores, enabling reconstructions of past flora and fauna. We show that high-altitude southern Greenland, currently lying below more than 2 kilometers of ice, was inhabited by a diverse array of conifer trees and insects within the past million years. The results provide direct evidence in support of a forested southern Greenland and suggest that many deep ice cores may contain genetic records of paleoenvironments in their basal sections.  相似文献   

Evaluation of transdermal fentanyl patch attachment in dogs and analysis of residual fentanyl content following removal     

Reed F  Burrow R  Poels KL  Godderis L  Veulemans HA  Mosing M 《Veterinary anaesthesia and analgesia》2011,38(4):407-412

Objective To investigate whether the method used to attach matrix‐type fentanyl patches influences the degree of skin attachment and the amount of active drug remaining in patches after use. Study design Prospective, randomised clinical study. Study population Fifteen adult dogs of mixed breeds. Methods Two equally sized matrix‐type fentanyl patches were attached to the dorsal third of the lateral thorax of fifteen dogs for 72 hours. The two patches were attached using different techniques: Method AD used an adhesive dressing in combination with a transparent film. Method TG used tissue adhesive applied to the edges of the patch. After 72 hours the patches were removed and the proportion of the patch attached at this time calculated. The residual content of the patches was analysed using a validated gas chromatography–mass spectrometery (GC–MS) analysis technique. Results After 72 hours of continuous attachment, the mean proportion of drug uptake for method AD was 17.2 (SD ± 11.1)% and for method TG this was 16.9 (SD ± 7.3)%. The median proportion of attachment for method AD was 100% and for method TG was 95.6%. Conclusions The method of attachment did not significantly influence the uptake of fentanyl from matrix‐type patches. The method of attachment resulted in a significant difference in the proportion of the patch attached 72 hours after placement, with method AD resulting in a greater median proportion of attachment than TG. Clinical relevance The method used to attach matrix‐type fentanyl patches to dogs should not interfere with drug uptake. The residual fentanyl content remaining in these patches after 72 hours of continuous application is significant and could lead to intoxication if ingested by humans.  相似文献   

Effect of manganese on the resistance of tomato to Pseudocercospora fuligena   总被引：1，自引：0，他引：1  

Gregor Heine  Johannes F. J. Max  Hendrik Führs  Diana W. Moran‐Puente  Dimitri Heintz  Walter J. Horst 《植物养料与土壤学杂志》2011,174(5):827-836

Black leaf mold caused by Pseudocercospora fuligena is an important fungal disease of tomato in Southeast Asia. The objective of this study was to evaluate the control of this disease using high manganese (Mn) applied to the root substrate and to evaluate the role of the leaf apoplast in plant response to fungal infection. In a nethouse experiment in Thailand, Mn above the optimum for plant growth but below toxicity increased resistance of tomato plants to black leaf mold. Enhanced resistance caused by Mn was also obtained when tomato plants were grown under controlled conditions in a mist chamber and artificially inoculated with the fungus. Manganese significantly increased plant peroxidases in the leaf apoplast. The highest peroxidase activity was measured when plants were inoculated with Pseudocercospora fuligena. Defense‐related proteins in the leaf apoplast increased when plants were inoculated with Pseudocercospora fuligena but not when treated with high Mn. It is concluded that Mn above the optimum level for plant growth can contribute to the control of Pseudocercospora fuligena in tomato. The Mn effect on disease resistance is associated with the activation of plant peroxidases in the leaf apoplast. A systemic response, possibly mediated by NADH peroxidase activity, also seems to trigger disease resistance in leaves with low Mn concentrations.  相似文献   

Retraction     

Bao Z  Batlogg B  Berg S  Dodabalapur A  Haddon RC  Hwang H  Kloc C  Meng H  Schön JH 《Science (New York, N.Y.)》2002,298(5595):961

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