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111.
Pheromone Response Inhibitors of the Corn Stalk Borer Sesamia nonagrioides. Biological Evaluation and Toxicology 总被引:1,自引:0,他引:1
Magí Riba Albert Sans Pep Bau Gérard Grolleau Michel Renou Angel Guerrero 《Journal of chemical ecology》2001,27(9):1879-1897
The behavioral activity of some trifluoromethyl ketones (TFMKs) as inhibitors of the pheromone activity of the corn stalk borer Sesamia nonagrioides (Lef.) (Lepidoptera: Noctuidae) is reported. The most closely-related analogue to the pheromone tested, (Z)-11-hexadecenyl trifluoromethyl ketone (Z11-16:TFMK), elicited a significant decrease in the number of male catches in traps baited with mixtures with the pheromone in 1:1 and 10:1 ratios in comparison to the pheromone alone. The E isomer of the analogue as well as two highly hydrated ketones, 3-octylthio-1,1,1-trifluoropropan-2-one (OTFP) and 1,1-difluoropentadecyl trifluoromethyl ketone, were inactive. Conversely, the saturated TFMKs n-dodecyl trifluoromethyl ketone and, particularly, n-hexadecyl trifluoromethyl ketone induced a synergistic effect when mixed with the synthetic pheromone in 10:1 ratio. However, in a wind tunnel these chemicals did not elicit any differential effect on flying moths attracted to a source containing a 10:1 blend of the analogue and the pheromone. In a dual choice bioassay with two dispensers, containing the pheromone alone, and mixtures of Z11-16:TFMK and the pheromone and separated 5 cm apart, males showed no particular preference for either dispenser. The ketone mixture, however, induced moths to execute erratic flights with frequent crosswind counter-turns and intersections with plume boundaries. The total number of contacts with the source were reduced when a control dispenser was paired with a dispenser containing Z11-16:TFMK and pheromone. Z11-16:TFMK and OTFP showed little toxicity on mice with a LD50 of 1 g/kg after the 6th day of treatment. For comparitive purposes, the major component of the pheromone, Z11-16:Ac, displayed a LD50 of 5 g/kg 6 days after application. Our results provide additional information about the activity of the TFMKs, which might be useful for the utilization of these chemicals in future pest control studies. 相似文献
112.
Huang TC Zhang G Guerrero T Starkschall G Lin KP Forster K 《Computer methods and programs in biomedicine》2006,84(2-3):124-134
In radiotherapy treatment planning, tumor volumes and anatomical structures are manually contoured for dose calculation, which takes time for clinicians. This study examines the use of semi-automated segmentation of CT images. A few high curvature points are manually drawn on a CT slice. Then Fourier interpolation is used to complete the contour. Consequently, optical flow, a deformable image registration method, is used to map the original contour to other slices. This technique has been applied successfully to contour anatomical structures and tumors. The maximum difference between the mapped contours and manually drawn contours was 6 pixels, which is similar in magnitude to difference one would see in manually drawn contours by different clinicians. The technique fails when the region to contour is topologically different between two slices. A solution is recommended to manually delineate contours on a sparse subset of slices and then map in both directions to fill the remaining slices. 相似文献
113.
Gemma Julio Dolores Merindano Marc Canals Miquel Ralló 《Microscopy research and technique》2010,73(11):1059-1066
Several processing techniques of digital images allowed us to quantify the percentage of cell surface covered by microprojections (microvilli or microplicae) (SCM), the adhesion between epithelial cells by the parameter intercellular junctions (IJ), the size (cell area), shape (cell shape) and shade (cell shade) of cells on the corneal epithelium of nine rabbits. The data were analyzed and the epithelial cells were classified into three groups by cluster analysis. Assuming the representativeness of the sample, our findings suggest that for a normal corneal epithelium, 80% of the cells could show SCM >41%, and IJ >0.98 (being one a cell to cell junction without disruptions). Standard deviations of cell shade lower than 21 gray levels could indicate a tendency to lose the cell shade mosaic. Normal corneas could show a majority of cells (54–69%) included in group 2 with smaller mean size (80% of cells with cell area <242 μm2), higher SCM (80% of cells with SCM >44.83%), polygonal mean shape and brighter shade. Group 1 (15–30% of cells) could show a larger mean size (80% of cells with cell area >494 μm2), lower SCM (although 80% of cells with SCM >32.61%), circular mean shape and darker electron reflex. Group 3 could display a medium mean size, higher SCM (similar to group 2), circular mean shape (similar to group 1), and brighter shade. These analyses could possibly be used to further assess the corneal response to ocular drugs, contact lens, and surgical procedures or to discriminate between pathology stages. Microsc. Res. Tech. 73:1059–1066, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
114.
The Generalized Integral Transform Technique is employed in the hybrid numerical-analytical solution of the steady two-dimensional
Navier–Stokes equations, defined within arbitrarily shaped domains, for incompressible laminar channel flow. The formalism
is illustrated for the classical test-case of laminar flow in a gradual expansion duct. Numerical results with automatic global
accuracy control are obtained for suggested values of Reynolds numbers in the literature, and critically compared against
previously reported benchmark solutions for the same problem. The relative merits of the proposed approach are then pointed
out.
Received 24 May 1999 相似文献
115.
Aitor Mata M. Dolores Mu?oz Emilio Corchado Juan M. Corchado 《Journal of Mathematical Imaging and Vision》2012,42(2-3):212-224
A novel hybrid forecasting Case-Based Reasoning (CBR) system is presented in this interdisciplinary study in which an isotropic buffer operator is applied for case-based creation. Commonly used as an image analysis technique by commercial Geographic Information Systems (GIS), the buffer operator in this particular system calculates the area of an oil slick for prediction and visualization tasks. The use of the buffer operator improves the quality of the data used by the system and in consequence the quality of the results obtained. The system generates predictions by using historical data on oil-slick formation following a spill. 相似文献
116.
Enzyme-modified cheeses (EMCs) are used to impart flavour to imitation cheese products. Cheeses (pH 6 or 5.5) were formulated with 5% w/w EMC, having low, medium or high levels of lipolysis and were examined by a sensory panel. Free fatty acid analyses were performed using SPME/GC. The flavour profile of the flavoured cheeses was affected by EMC composition and pH of the cheese base. Cheeses at a pH of 6.0, flavoured with low lipolysis EMCs, were described as ‘bland’. Lowering the pH of the cheese matrix to 5.5 appeared to increase the flavour intensity of the cheese flavoured with low lipolysis EMC and panellists ranked this cheese the highest, describing its flavour as ‘well-balanced and ‘cheesy’. This study shows that the flavours of imitation cheeses are influenced by the level of lipolysis of the EMCs used to flavour them and also by the pH of the cheese base. 相似文献
117.
A. Redondo M. José Villanueva M. Dolores Rodriguez M. Dolores Saco 《European Food Research and Technology》1997,205(6):457-463
Different methods have been used to evaluate variations in the dietary fibre content of carrots and turnips during autoclaving. Autoclaving was carried out at 121°C under pressure for 15 min. The methods used were the gravimetric (neutral and acid detergent fibre) method, the enzymatic-gravimetric method for (insoluble and soluble fibre and the spectrophotometric method for pectic substances. When the methodologies were compared it was observed that in raw carrots and turnips, the neutral detergent fibre and insoluble fibre contents were statistically different (P<0.05). This was not the case for processed samples of the vegetables. The correlation between the different methodologies was studied. A good correlation was found between neutral detergent fibre and insoluble fibre in raw turnips (r = 0.999). Variance analysis indicated that quantitative variations resulting after thermal treatment were statistically significant (P<0.05) for neutral detergent fibre in carrots (raw = 1.97%, processed = 1.68%), and for pectic substances in carrots (raw = 0.54%, processed = 0.47%) and turnips (raw = 0.33%, processed = 0.25%). Optical microscopy has been used to identify different dietary fibre components in raw and processed samples. 相似文献
118.
M de Abood Z de Castillo F Guerrero M Espino KL Austin 《Canadian Metallurgical Quarterly》1997,56(5):313-316
Forty-three homozygous (SS) female sickle cell anemic patients with a history of at least one painful crisis per month and desiring a reversible contraceptive were administered DMPA/3 months or Microgynon monthly. A third group of 16 surgically sterilized patients served as control. Patients were followed for 1 year to assess possible effects of the contraceptives on the patients' painful crises. No changes were observed in any of the groups in the hematological parameters. At the end of the study, 70% of the patients receiving DMPA were pain-free and only 16% of those still reporting painful crises rated them as intense. Patients receiving Microgynon also had an amelioration of the painful crises, although at a lower rate; after 12 months, 45.5% still experienced some crises. Although less marked than in the other groups, 50.5% of the control patients also reported an improvement of their painful crisis, which may be a result of closer medical care. 相似文献
119.
Pilar Manglano María Jesús Lagarda María Dolores Silvestre Carmen Vidal Gonzalo Clemente Rosaura Farr 《European Journal of Lipid Science and Technology》2005,107(11):815-823
A study is made of the effects of storage (time and temperature) on the lipid fraction of four milk‐based adapted infant formulas with basically the same composition, though differing in the iron salt added (lactate or sulfate) and/or the vitamin E source (α‐tocopherol or α‐tocopherol acetate). Peroxide value, hydroperoxide C18 percentage and thiobarbituric acid‐reactive substance (TBARS) content were used as indicators of lipid peroxidation. Fat contents remained stable throughout storage. Peroxide values increased from the first storage month and were affected by storage time, although they exhibited irregular behavior. Storage time and temperature affected hydroperoxide percentage, which was seen to be the earliest indicator of lipid oxidation, being measurable in newly manufactured formulas. TBARS values were only affected by storage time. No statistically significant differences were found among the four infant formulas for any of the lipid oxidation indicators. 相似文献
120.
This paper investigates multiple reorder point, periodic replenishment systems similar to those utilized on board some U.S. naval vessels for Selected Item Management (SIM). This inventory system is of interest since it involves both regular and priority replenishment, three reorder points, and cyclical restocking of regular orders. A simulation model is developed to study the impact of demand distribution, cycle time, priority order leadtime, and the quantity of units ordered on the performance of the system. It is found that the frequency of service and days without shortages performance measures can be maximized by setting the reorder points at equal intervals between the zero level and the high level. Also, a power approximation model is presented that estimates the high level that will lead to a desired percent days without shortage percentage. 相似文献