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Background: Palmer amaranth (Amaranthus palmeri S. Wats.), common waterhemp (Amaranthus tuberculatus var. rudis), and redroot pigweed (Amaranthus retroflexus L.) are major weeds occurring in fields throughout Nebraska with recurrent grower complaints regarding control with glyphosate. The objective of this study was to investigate the frequency and distribution of glyphosate-resistant Palmer amaranth, common waterhemp, and redroot pigweed populations in Nebraska. The study also aimed to investigate how agronomic practices influence the occurrence of glyphosate resistance in the three Amaranthus species., Results: Glyphosate resistance was widespread in common waterhemp (81% of the screened populations), few Palmer amaranth populations were glyphosate-resistant (6% of the screened populations), whereas no glyphosate-resistant redroot pigweed populations were identified in Nebraska. Weed species, geographic region within the state, and current crop were the most important factors predicting the occurrence of glyphosate resistance in fields infested with Amaranthus species in Nebraska., Conclusion: The intensive glyphosate selection pressure exerted in soybean (Glycine max) fields in eastern Nebraska is one of the major factors causing widespread occurrence of glyphosate resistance in common waterhemp in the state. The relatively low frequency of glyphosate-resistant Palmer amaranth in the state highlights the importance of the application timing and the adoption of multiple modes of action in weed management practices to delay the evolution of glyphosate resistance. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

The current study examined patterns of psychopathology, drug and alcohol use, and sexual behavior associated with childhood abuse and neglect in a high-risk sample of low-income African American girls seeking mental health treatment. Participants (N=177) were African American girls recruited from mental health clinics serving low-income communities in Chicago, IL and followed over six waves of data collection (T1-T6) reflecting early (mean age 14) to late (mean age 17) adolescence. Child abuse and neglect history was determined from adolescent and caregiver reports. Latent curve modeling examined patterns of internalizing and externalizing psychopathology, drug and alcohol use, sexual experience, and risky sexual behavior reported by girls and associations with reported child abuse and neglect. Overall, these trajectories indicated a decrease in internalizing and externalizing symptoms, stability of drug and alcohol use, and an increase in sexual experience and risky sexual behaviors over time. Child abuse and neglect was associated with increased internalizing symptoms and sexual experience at baseline and with externalizing symptoms and risky sexual behavior both at baseline and the final point. Child abuse and neglect was not significantly associated with alcohol or drug use. This study adds to the literature on the long-term consequences of child abuse and neglect by demonstrating patterns of psychopathology and risky behavior that persist over time in a high-risk group of girls with self or parent reported histories of abuse and neglect. Interventions that address externalizing problems and health risk behaviors may be of particular importance for this population., (Copyright © 2015. Published by Elsevier Ltd.)