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111.
Soybean rust in Brazil is currently controlled with several commercial fungicide premixes composed of demethylation inhibitors (EPOXiconazole, CYPRoconazole, PROThioconazole, TEBUconazole), quinone-outside inhibitors (AZOXystrobin, TriFLoXystrobin, PYRAclostrobin, PICOxystrobin), and succinate demethylation inhibitors (BENZovindiflupyr, BIXaFen, FLUXapyroxad). Here, we summarize the performance of eight premixes evaluated in 177 cooperative trials conducted in 46 locations across 10 states from 2015 to 2020. All fungicide treatments were sprayed three times starting at R1/R2. Percentage control (, %), from back-transforming meta-analytic estimates of the log of the ratio, ranged from 56.2% (PICO + CYPR) to 76.8% (BIXF + TFLX + PROT). Estimates of mean yield difference (, kg/ha) between fungicide-treated and untreated plots were greatest for BIXF + TFLX + PROT (1,080) followed by PICO + BENZ (1,010), PYRA + EPOX + FLUX (981.5), AZOX + BENZ (910), TFLX + PROT (891), PICO +TEBU (682), TFLX + CYPR (646), and PICO + CYPR (600). Significant declines in both and in as little as 4 years were detected for AZOX + BENZ (35.3%; 550 kg/ha) and PICO + BENZ (15.5%; 359.8 kg/ha). Variance in was reduced by the inclusion of baseline severity as covariate. In trials where baseline disease was ≥70%, yield was 250 kg/ha greater compared to areas with low baseline disease. Disease control and yield response were generally greater in the south-east, where the frequency of profitable scenarios was 30% higher on average than in the north-west. Results of this meta-analysis are critical for supporting decisions during planning of fungicide programmes.  相似文献   
112.
The percent explained variation (r2) of tensile strength (T) of dimension lumber can be accounted for primarily by apparent modulus of elasticity (Ea).Tensile strength ratio, a good index of T of structural lumber, and Ea are both dependent on relative knot size, making T a function of Ea. This theoretical relationship helps to increase r2 when T is regressed on Ea and gives the cause and effect for some multiple regression analyses. An independent variable was identified on the basis of this theory.Shortening the gage length enhances ability to predict T when flatwise bending Ea or tension Ea is used as an independent variable, but not when edgewise bending Ea is used.Two single variables not previously reported, Ea measured in flatwise bending on 16-inch gage length (EF 16) and Ea measured in tension on 6-inch gage length (ET 6) (based solely on deformation measurements), are individually able to explain approximately as much variation of T (r2=0.75) as the combination of Ea measured flatwise on 48-inch gage length (span length for the existing American grading machines), and ASTM bending strength ratio. The combination of EF 16 and ET6 can explain 85% of the variation of T. The highest r2 (0.87) was obtained when a modified bending strength ratio was added to these new variables.This research was done in partial fulfillment for the degree of Master of Science, Department of Civil Engineering, University of Wisconsin, Madison, Wis., May 1971.  相似文献   
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114.
Buckwheat is a pseudocereal with a strong characteristic aroma. Compounds responsible for the aroma of buckwheat groats were recently identified, but the distribution of aromatic compounds between different fractions of the buckwheat kernel (flour, bran, and husk) is not yet known. In this study, the composition of aromatic compounds in buckwheat seed fractions was investigated and compared to the composition of aromatic compounds in groats produced from the same batch of buckwheat seeds. Volatiles from each sample were extracted with simultaneous distillation/extraction with a Likens‐Nickerson apparatus. Extracts were analyzed by gas chromatography coupled with mass spectrometry (GC‐MS) with electron ionization. Apart from the aroma molecules present in all fractions, compounds that are present only in flour or bran, but not in groats, were also found. Furthermore, some compounds were identified only in buckwheat groats but not in buckwheat flour or bran [octanal, (E,E)‐2,4‐heptadienal, (E)‐2‐decenal, and (E,E)‐2,4‐decadienal], others were identified only in husks [(E)‐2‐hexenal, heptanal, (E,E)‐2,4‐hexadienal, phenylacetaldehyde, and alpha‐bisabolol].  相似文献   
115.
The soybean cyst nematode (SCN) is one of the most economically important pathogens of soybean. Molecular mapping of quantitative trait loci (QTL) for resistance to SCN is a proven useful strategy in order to assist in the development of resistant soybean cultivars. In the present study, a Bayesian modeling approach was performed to map QTL controlling genetic resistance to SCN races 3 and 14. For this purpose, a population of recombinant inbred lines derived from the cross between line Y23 (susceptible) and cv. Hartwig (resistant) was used. A total of 144 microsatellites markers (Simple Sequence Repeats) were selected and synthesized for mapping purpose. Posterior marginal parameter distributions were computed using the Reversible Jump Markov Chain Monte Carlo (RJ-MCMC) algorithm. It was determined the existence of four QTLs on three linkage groups (LG); that is LG A2 for race 3, LG C2 for race 14, and LG G for both races. The estimates of posterior modes of the heritability were 0.038 and 0.53 for the LGs A2 and G respectively (race 3). For the race 14 the posterior modes of the heritability were 0.044 and 0.05 for the LGs C2 and G. The identified QTLs explained about 57 and 9 % of the total phenotypic variance, for the races 3 and 14, respectively. These results confirm the effectiveness of the Bayesian method to map QTL controlling resistance to SCN in soybean. Accordingly, integrating QTL mapping with Bayesian methods will enable response to selection for quantitative traits of interest in soybean to be improved.  相似文献   
116.
Humans create vast quantities of wastewater through inefficiencies and poor management of water systems. The wasting of water poses sustainability challenges, depletes energy reserves, and undermines human water security and ecosystem health. Here we review emerging approaches for reusing wastewater and minimizing its generation. These complementary options make the most of scarce freshwater resources, serve the varying water needs of both developed and developing countries, and confer a variety of environmental benefits. Their widespread adoption will require changing how freshwater is sourced, used, managed, and priced.  相似文献   
117.
The present study characterized the homologous and heterologous immune response in type-I porcine reproductive and respiratory syndrome virus (PRRSV) infection. Two experiments were conducted: in experiment 1, eight pigs were inoculated with PRRSV strain 3262 and 84 days post-inoculation (dpi) they were challenged with either strain 3262 or strain 3267 and followed for the next 14 days (98 dpi). In experiment 2, eight pigs were inoculated with strain 3267 and challenged at 84 dpi as above. Clinical course, viremia, humoral response (neutralizing and non-neutralizing antibodies, NA) and virus-specific IFN-γ responses (ELISPOT) were evaluated all throughout the study. Serum levels of IL-1, IL-6, IL-8, TNF-α and TGF-β were determined (ELISA) after the second challenge. In experiment 1 primo-inoculation with strain 3262 induced viremia of ≤ 28 days, low titres of homologous NA but strong IFN-γ responses. In contrast, strain 3267 induced longer viremias (up to 56 days), higher NA titres (≤ 6 log2) and lower IFN-γ responses. Inoculation with 3267 produced higher serum IL-8 levels. After the re-challenge at 84 dpi, pigs in experiment 1 developed mostly a one week viremia regardless of the strain used. In experiment 2, neither the homologous nor the heterologous challenge resulted in detectable viremia although PRRSV was present in tonsils of some animals. Homologous re-inoculation with 3267 produced elevated TGF-β levels in serum for 7–14 days but this did not occur with the heterologous re-inoculation. In conclusion, inoculation with different PRRSV strains result in different virological and immunological outcomes and in different degrees of homologous and heterologous protection.  相似文献   
118.
Squamous cell carcinomas (SCC) of the skin are commonly described in cats. Reported treatments include surgery, radiation therapy and photodynamic therapy. This preliminary study reports on the management of these lesions combining the local administration of bleomycin (plus hyaluronidase for a more uniform distribution) with permeabilizing biphasic electric pulses. Nine cats with SCC graded T(2)-T(4) were treated over a 5 year period, and each cat received two sessions of electrochemotherapy (ECT) 1 week apart. The side effects of this treatment were minimal and limited to mild erythema of the nose. Seven of the cats (77.7%) had a complete response lasting up to 3 years. ECT seems to be a safe and effective option for the treatment of feline sun-induced squamous cell carcinomas and warrants further investigation.  相似文献   
119.
Tetratrichomonas gallinarum is a widespread intestinal parasite of galliform and anseriform birds. The pathogenicity of this species is controversial, presenting an unsettled problem as yet. We analysed the polymorphism and genetic relationship among 29 isolates of T. gallinarum obtained from eight bird species and five T. gallinarum-like isolates from the oral cavity and lower respiratory tract of human patients. Two methods were used for the analyses: RAPD and sequencing of 16S rRNA, 5.8S rRNA, ITS1 and ITS2 genes, both producing consistent and well-supported results. The isolates were divided into five groups, A-E, with eleven subgroups. The distance between groups E, D and the cluster A-B-C considerably exceeded usual intraspecific polymorphism seen in trichomonads. Moreover, the largest subgroup, A2 (containing 18 isolates), was divided into three branches according to the host specificity. All isolates from humans were placed into avian subgroups A2 and B2. We conclude that our isolates represent, at least, three morphospecies or rather complexes of several cryptic species. Since certain species of the T. gallinarum complex can differ in their biological characteristics and some of them can infect humans, the problem of T. gallinarum pathogenicity should be re-examined with regard to specific genetic groups and zoonotic potential of some of these lineages should be considered.  相似文献   
120.
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