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Laboratory and field experiments were conducted to determine the effectiveness of microbial and chemical insecticides for supplemental control of bollworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), on non-Bt (DP1441RF) and Bt (DP1321B2RF) cottons. Neonate and 3rd instar larvae survival was evaluated on leaf tissue treated with microbial and chemical insecticides including a commercial formulation of Bacillus thuringiensis (Dipel), a Heliothis (Helicoverpa) nuclear polyhedrosis virus (NPV; Gemstar), λ-cyhalothrin (Karate Z), and chlorantraniliprole (Prevathon). Residual activity of insecticides was measured in a small plot field experiment. The performance of microbial insecticides, with the exception of a mid-rate of Dipel with neonate larvae, was comparable with that of chemical treatments on non-Bt cotton leaves with regard to 1st and 3rd instar bollworm mortality at 10 d and pupal eclosion at 20-d post treatment. Production-level field evaluations of supplemental bollworm control in non-Bt and Bt cottons with NPV, λ-cyhalothrin, and chlorantraniliprole were also conducted. During both years of the field study, all chemical and microbial treatments were successful in suppressing bollworm larval densities in non-Bt cotton below economic threshold levels. Overall, net returns above bollworm control, regardless of treatment, were negatively correlated with larval abundance and plant damage. In addition, there was no economic benefit for supplemental control of bollworms in Bt cotton at the larval densities observed during this study. These data provide benchmark comparisons for insect resistance management with microbial and chemical insecticides in Bt and non-Bt cottons and strategic optimization of the need to spray non-Bt and Bt cotton in IRM programs., (Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.)

The aim of this study was to examine the potential relationship between the occurrence of orthodontic root resorption and presence of dental anomalies such as tooth agenesis and pipette-shaped roots. Dental anomalies and root resorption were assessed on dental panoramic tomographs (DPT) of 88 subjects, 27 males and 61 females, mean age 28.4 (SD = 11.3 years), selected from orthodontic patients on the basis of the following exclusion criteria: previous fixed appliance treatment, bad quality of the DPTs and no visibility of the periodontal ligament of every tooth, and younger than 15 years of age at the onset of treatment with fixed edgewise appliance lasting at least 18 months. A pipette-shaped root was identified as defined by a drawing. Tooth agenesis was assessed on DPTs and from subjects' dental history. Root resorption was calculated as the difference between the root length before and after treatment, with and without a correction factor (crown length post-treatment/crown length pre-treatment). If one of the four upper incisors showed root resorption of ≥2.3 mm with both formulas, the patient was scored as having root resorption. Chi-square tests indicated that there was no relationship between orthodontic root resorption and agenesis (P = 0.885) nor between orthodontic root resorption and pipette-shaped roots (P = 0.800). There was no relationship between having one of the anomalies and root resorption either (P = 0.750). In the present study, it was not possible to confirm on DPTs a relationship between orthodontic root resorption and dental anomalies, such as agenesis and pipette-shaped roots.

The presence of dental anomalies has been rated radiographically in a number of studies. However, since the reliability of the assessment of these anomalies has rarely been investigated, the aim of this study was to examine inter- and intraexaminer agreement in identifying morphological dental anomalies, such as tooth agenesis, dilacerated, pipette-shaped, blunt, pointed, and short roots. Pre-treatment panoramic radiographs of 40 patients (13 males and 27 females; mean age 27.7 ± 10.8 years) treated between 1983 and 2008 were selected. Four examiners independently assessed the radiographs twice. For a dilacerated root and agenesis, a definition was given. For pipette-shaped, blunt, or pointed roots, a drawing was shown, and for a short root, a ratio was used to identify the anomaly. Intraexaminer agreement of the assessments of the dental anomalies was presented by Cohen's Kappa and varied between -0.01 for short roots and 1.00 for agenesis. With respect to short roots, three of the examiners did not rate them to be present on at least one measurement occasion. This implies that intraexaminer agreement could not be calculated for these three examiners. Interexaminer agreement for dilacerated roots varied between 0.14 and 0.50, for pipette-shaped roots between -0.01 and 0.33, for blunt roots between 0.05 and 0.32, and for pointed roots between 0.17 and 0.37. All values for agenesis were 1.00. It can be concluded that assessing agenesis on panoramic radiographs is reliable. Rating the presence of dilacerated, pipette-shaped, blunt, pointed, and short roots on panoramic radiographs, however, does not result in a reliable assessment.