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1.
Proc Natl Acad Sci U S A ; 115(13): 3320-3325, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29531049

RESUMO

Transgenic crops containing the bacterium Bacillus thuringiensis (Bt) genes reduce pests and insecticide usage, promote biocontrol services, and economically benefit growers. Area-wide Bt adoption suppresses pests regionally, with declines expanding beyond the planted Bt crops into other non-Bt crop fields. However, the offsite benefits to growers of other crops from such regional suppression remain uncertain. With data spanning 1976-2016, we demonstrate that vegetable growers benefit via decreased crop damage and insecticide applications in relation to pest suppression in the Mid-Atlantic United States. We provide evidence for the regional suppression of Ostrinia nubilalis (Hübner), European corn borer, and Helicoverpa zea (Boddie), corn earworm, populations in association with widespread Bt maize adoption (1996-2016) and decreased economic levels for injury in vegetable crops [peppers (Capsicum annuum L.), green beans (Phaseolus vulgaris L.), and sweet corn (Zea mays L., convar. saccharata)] compared with the pre-Bt period (1976-1995). Moth populations of both species significantly declined in association with widespread Bt maize (field corn) adoption, even as increased temperatures buffered the population reduction. We show marked decreases in the number of recommended insecticidal applications, insecticides applied, and O. nubilalis damage in vegetable crops in association with widespread Bt maize adoption. These offsite benefits to vegetable growers in the agricultural landscape have not been previously documented, and the positive impacts identified here expand on the reported ecological effects of Bt adoption. Our results also underscore the need to account for offsite economic benefits of pest suppression, in addition to the direct economic benefits of Bt crops.


Assuntos
Bacillus thuringiensis/genética , Produtos Agrícolas , Inseticidas/farmacologia , Mariposas/fisiologia , Controle Biológico de Vetores , Doenças das Plantas/prevenção & controle , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Animais , Resistência a Inseticidas , Mariposas/classificação , Doenças das Plantas/genética , Doenças das Plantas/parasitologia , Dinâmica Populacional , Zea mays/metabolismo , Zea mays/parasitologia
2.
Ear Hear ; 39(2): 278-292, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28837426

RESUMO

OBJECTIVES: Emerging evidence suggests that early phonological awareness in deaf and hard-of-hearing (DHH) children with functional hearing is significantly related to their reading acquisition, and the assessment of phonological awareness can play a critical role in preventing reading difficulties. Validation of the scores obtained from standardized assessments when used with DHH students is crucial to support the assessments' intended interpretations and implications of test scores. Using archival data sets, the aim of this study was twofold: (a) to establish the factorial validity of the item scores on the Test of Preschool Early Literacy-Phonological Awareness (TOPEL-PA) for DHH children with functional hearing and hearing children and (b) to test measurement invariance across these groups. Our archival data sets included assessments of DHH children, hearing children from low socioeconomic status (SES) backgrounds, and hearing children from a range of SES backgrounds. We hypothesized that a second-order unifying ability, Phonological Awareness, along with four first-order subtest factors would explain inter-item associations among the 27 items on the TOPEL-PA. We further hypothesized that patterns of associations among the item scores would be similar across groups and that the individual items would function similarly across groups. DESIGN: Seven hundred and thirty-three children from three samples participated in the study; 171 were DHH children (Mage = 58.7 months old, SDage = 12.5 months old), 195 were low-SES hearing children (Mage = 55.5 months old, SDage = 3.5 months old), and 367 were diverse-SES hearing children (Mage = 53.4 months old, SDage = 8.9 months old). All DHH children were able to identify the referent of monosyllabic spoken words on the Early Speech Perception Test. RESULTS: Test of confirmatory item factor analyses of the hypothesized second-order factor structure revealed that a second-order unifying ability along with four first-order subtest factors well explained associations among the item scores for all groups. This aligned with the scoring structure of the TOPEL-PA, providing strong evidence for factorial validity of the item scores for DHH children as well as for hearing children groups. The measurement invariance test results provided evidence that the vast majority of TOPEL-PA items functioned similarly for hearing children and DHH children with speech perception abilities, suggesting that the utility of the assessment scores obtained from DHH children is consistent with the scores obtained from hearing children. CONCLUSION: Results of our study suggest that researchers and practitioners can use the TOPEL-PA to assess DHH children with functional hearing. It also suggests that the two skills measured on the TOPEL-PA (blending and elision) are qualitatively similar for DHH and hearing children, but the latent mean score obtained from the DHH children significantly differed from those of the hearing groups, suggesting a quantitative difference.


Assuntos
Linguagem Infantil , Surdez , Transtornos da Audição , Alfabetização , Pessoas com Deficiência Auditiva , Fonética , Pré-Escolar , Feminino , Humanos , Masculino , Psicometria , Leitura , Classe Social
3.
GM Crops ; 1(5): 337-43, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21844691

RESUMO

Sweet corn, Zea mays L., transformed to express a novel vegetative insecticidal protein, Vip3A (event MIR162, Syngenta Seeds, Inc..), produced by the bacterium, Bacillus thuringiensis (Bt), was evaluated over four field seasons in Maryland and two field seasons in Minnesota for efficacy against the corn earworm, Helicoverpa zea (Boddie). Hybrids expressing the Vip3A protein and pyramided in hybrids also expressing the Cry1Ab Bt protein (event Bt11, ATTRIBUTE(®), Syngenta Seeds, Inc.) were compared to hybrids expressing only Cry1Ab or to genetically similar non-Bt hybrids each year. In addition to H. zea efficacy, results for Ostrinia nubilalis (Hübner) and Spodoptera frugiperda (J.E. Smith) are presented. Over all years and locations, the non-Bt hybrids, without insecticide protection, averaged between 43 and 100% ears infested with a range of 0.24 to 1.74 H. zea larvae per ear. By comparison, in the pyramided Vip3A x Cry1Ab hybrids, no larvae were found and only minimal kernel damage (likely due to other insect pests) was recorded. Hybrids expressing only Cry1Ab incurred a moderate level of H. zea feeding damage, with surviving larvae mostly limited to the first or second instar as a result of previously documented growth inhibition from Cry1Ab. These results suggest that the Vip3A protein, pyramided with Cry1Ab, appears to provide the first "high-dose" under field conditions and will be valuable for ongoing resistance management.


Assuntos
Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Zea mays/genética , Zea mays/parasitologia , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Lepidópteros , Controle Biológico de Vetores
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