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41.
The citrus leafminer is an important vector of citrus canker in many of the major citrus production areas of the world. (7Z,11Z)-Hexadecadienal was reported as a sex attractant for this insect in the 1980s, based on trap catches during pheromone screening trials in Japan. However, attempts to reproduce this work in other areas of the world have not been successful. We report here that (7Z,11Z)-hexadecadienal is only one component of the pheromone, with the other critical component being the analogous trienal, (7Z,11Z,13E)-hexadecatrienal. Both compounds were identified in the effluvia from live female moths by coupled gas chromatography (GC)-electroantennography using nonpolar and polar GC columns, and the identifications were confirmed by comparisons of mass spectra with those of authentic standards. Stereoisomers of the two compounds, and a number of analogs, were synthesized to confirm the identifications. In field trials, neither compound alone was attractive to male moths, but blends of the two were highly attractive, with thousands of insects being caught per trial. Addition of the isomeric (7Z,11Z,13Z)-hexadecatrienal inhibited attraction to the two-component blend. Electronic Supplementary Material Supplementary material is available for this article at and accessible for authorized users. This paper and the preceding paper (Leal et al.) were submitted within a few days of each other. The editors and the authors agreed that they should be published in tandem.  相似文献   
42.
Fibroblast growth factor 23 (FGF-23) is elevated in patients with end-stage kidney disease and has been linked with mortality, vascular calcification, markers of bone turnover, and left ventricular hypertrophy. In this cohort study, we determined the correlates of FGF-23 (including cardiac troponin T [cTNT]) and determined its association with mortality over 3.5 years of follow-up in 103 prevalent hemodialysis patients. Mean age was 61.2 (15.5) and the mean dialysis vintage was 4.19 years (4.6). The median (interquartile range) FGF-23 was 1259 (491, 2885) RU/mL. Independent predictors (estimate standard error) of log-transformed FGF-23 concentrations included phosphorus (0.75 [0.237], P = 0.002) and cardiac troponin T (1.04 [0.41], P = 0.01). There were 57 deaths. In the fully adjusted model, the significant predictors of mortality included age and albumin. The independent association between FGF-23 and cTNT is a novel finding. Whether this relationship supports the possibility that a downstream effect of dysregulated phosphorous homeostasis may be enhanced cardiac remodeling requires further study.  相似文献   
43.
This article presents 154 pressure drop data points measured during two-phase flow of R-134a in horizontal return bends. The tube diameter is constant at 10.85 mm and the curvature ratio is either 7.74 or 5.53. Saturation temperature varies from 15 to 20°C, vapor quality from 0.05 and 0.95, and mass velocity ranges from 300 to 600 kg m?2 s?1. Return bend pressure drops are calculated by subtracting the straight tube pressure drop from the total measured pressure drop along the bend. The perturbations induced up- and downstream of the singularity are taken into account in the measurements. The comparison of the pressure drops for the two configurations (curvature ratio of 5.53 and 7.74) showed that they are greater (about 10%) for the larger curvature ratio. This can be attributed to the effect of the developed length on the pressure drop; on the other side the pressure gradients are larger for the lower curvature ratio, which can be explained by the effect of the centrifugal force and the perturbations up- and downstream of the return bend. The experimental data are compared against four prediction methods available in the literature. The Domanski and Hermès correlation is the best at predicting the present data.  相似文献   
44.
In this paper, a new method for supervised hyperspectral data classification is proposed. In particular, the notion of stochastic minimum spanning forest (MSF) is introduced. For a given hyperspectral image, a pixelwise classification is first performed. From this classification map, M marker maps are generated by randomly selecting pixels and labeling them as markers for the construction of MSFs. The next step consists in building an MSF from each of the M marker maps. Finally, all the M realizations are aggregated with a maximum vote decision rule in order to build the final classification map. The proposed method is tested on three different data sets of hyperspectral airborne images with different resolutions and contexts. The influences of the number of markers and of the number of realizations M on the results are investigated in experiments. The performance of the proposed method is compared to several classification techniques (both pixelwise and spectral-spatial) using standard quantitative criteria and visual qualitative evaluation.  相似文献   
45.
In this paper, 325 pressure drop data points measured in return bends have been collected from the literature. The database includes 3 different fluids (R-12, R-134a and R-410A) from two laboratories. Based on this database, a new method is proposed for predicting the pressure gradient in return bends, which is the sum of the frictional pressure gradient that would be obtained in straight tubes (predicted by Müller-Steinhagen and Heck, 1986 correlation) and the singular pressure gradient (proposed equation). The proposed correlation includes only two empirical constants and exhibits the correct physical limits. Using the proposed equation, simulations have been performed to predict the effect of fluid, mass velocity and saturation temperature on the singular pressure gradient.  相似文献   
46.
This paper presents a simple and general modeling primitive, called a block, based on a generalized cuboid shape. Blocks are laid out and connected together to constitute the base shape of complex objects, from which is extracted a control mesh that can contain both smooth and sharp edges. The volumetric nature of the blocks allows for easy topology specification, as well as CSG operations between blocks. The surface parameterization inherited from the block faces provides support for texturing and displacement functions to apply surface details. A?variety of examples illustrate the generality of our blocks in both interactive and procedural modeling contexts.  相似文献   
47.
48.
This paper addresses the estimation of local entropy generation rate for diabatic saturated two-phase flow of a pure fluid. Two different approaches have been adopted for this thermodynamic characterization: the separated flow model using the classical vapor flow quality, and the mixture model, using the thermodynamic vapor quality. Based on these two models, two distinct expressions for the local entropy generation have been proposed. The analysis explicitly shows the contribution of heat transfer and pressure drop respectively to the local entropy generation. The contribution due to phase-change process is also determined using the mixture model. The developed formulation is applied to analyze the thermodynamic performance of enhanced heat transfer tubes under different conditions. It is shown that enhanced tubes may be a relevant solution for reducing entropy generation at low mass velocities whereas smooth tubes remain the best solution at higher ones.  相似文献   
49.
Examined the effects of verbal practice training procedures in teaching counselor trainees to consistently respond to 2 aspects of client anger: form (passive or aggressive manner) and direction (toward or away from the counselor). 48 graduate students were randomly assigned to 1 of 3 videotaped counselor training procedures. After training, each S was assigned to 2 of the 4 anger conditions and was asked to conduct 2 10-min counseling sessions. Ss in either of the 2 experimental conditions, verbal practice with modeling or verbal practice without modeling, were significantly more consistent in responding to the confederate clients' anger than were those in the control group. The treatment effects were maintained 1 wk later. Significant differences were also found for direction of client anger and the interaction between treatments and direction. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
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