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The spotted lanternfly, Lycorma delicatula (White), is an orchard and forest pest native to China. Since its detection in Pennsylvania, USA in 2014, it has spread to other states as well. We conducted experiments to determine the flight capabilities of unmated vs. mated L. delicatula females to assess the relative threat posed by each type with regard to expanding the infestation area through their natural flight behaviors. Females were collected from mating pairs, captured on plants, and netted during flights averaging 24 m, then dissected and examined for male spermatophores, a diagnostic character for determining mating status. The weight, amount of yellow area on the abdomen, wing area, and body length and abdominal width was recorded from these females. Sedentary females on plants were selectively collected for their large and swollen abdomen. They were capable of only flying ~4 m when forcibly launched and were significantly heavier than the in-flight-captured females. More than 93% of these large, sedentary females had mated whereas

Allium leafminer, Phytomyza gymnostoma (Diptera: Agromyzidae), is an invasive species first recorded in the Western Hemisphere in 2015 and has expanded its range into northeastern and MidAtlantic states. Its host range encompasses Allium species grown for food and ornamentals, weedy species, species used for pollinator provisioning, and species of conservation concern. Using field and laboratory studies, we advanced methods for rearing, developed a phenology model for spring emergence, describe pupal development, and report on parasitism. Spring emergence was best detected by scouting wild alliums as opposed to emergence cages, and modeled using 350 degree-days above a lower threshold of 1.0°C. Spring adult flight occurred for about 5 wk. Larval development required 22 and 20 d at 17.5 and 25°C, respectively. Pupal development progressed along a color gradient, and an initial presence of fat cell clusters and an air bubble, followed by an exarate pupa. Pupal developed at 3–5% per day at 3°C and reached 25% per day at 21.5°C, but development was not successful at 30°C. Although parasitism rates were low, we documented two Chalcidoidea parasitoids, Halticoptera circulus (Walker) (Hymenoptera: Pteromalidae) and Chrysocharis oscinidis Ashmead (Hymenoptera: Pteromalidae). Together, these data provide baseline information to advance IPM for this invasive species both in crops and noncrop areas.

Aims We aim to determine if Pseudomonas fluorescens is a viable biological control for Erwinia tracheiphila within the insect vector, Acalymma vittatum. Methods and results Pseudomonas fluorescens secreted fluorescein and inhibited growth of E. tracheiphila in disc diffusion assays. To determine if this antagonism was conserved within the insect vector, we performed in vivo assays by orally injecting beetles with bacterial treatments and fluorescent in situ hybridization to determine bacterial presence within the alimentary canal. Conclusions Pseudomonas fluorescens inhibited the growth of E. tracheiphila on a nutrient-limiting medium. In situ experiments demonstrated that P. fluorescens is maintained within the alimentary canal of the beetle for at least 4 days, and co-occurred with E. tracheiphila. When beetles were first presented with Pseudomonas and then challenged with E. tracheiphila, E. tracheiphila was not recovered via FISH after 4 days. These data suggest that P. fluorescens has potential as a biological control agent to limit E. tracheiphila within the insect vector. Significance and impact of the study This is a novel approach for controlling E. tracheiphila that has the potential to decrease reliance on insecticides, providing a safer environment for pollinators and growers.

Commercial cucurbit production typically involves agriculturally intensive practices, with fields prepared using conventional tillage, plasticulture, and chemically based pest management. Conservation-based management options are limited. In this study, we consider two alternative strategies, strip tillage and the use of row covers. We compare their impact on the beneficial carabid beetle (Coleoptera: Carabidae) community in melons and squash, following conventional or organic systems, over two years. Multivariate analysis demonstrated that soil management system (strip tillage versus plasticulture) was the primary variable influencing carabid distribution; row cover was a less important factor. The response to soil management was species dependent. Some dominant species, such as Harpalus pensylvanicus DeGeer, demonstrated no preference for a particular soil treatment. For others, including the tiger beetle, Cicindela punctulata Olivier, and a slug predator, Chlaenius tricolor Dejean, activity-density was higher in strip-tillage production systems. Our analysis suggested that strip-tillage production systems support a richer, more diverse carabid community. These results demonstrate that even within intensive annual horticultural systems, production practices can play a critical role in shaping the beneficial arthropod community, potentially encouraging or limiting ecosystem services.

Erwinia tracheiphila is one of the most economically important pathogens of cucumbers, melons, squashes, pumpkins, and gourds in the northeastern and midwestern United States, yet its molecular pathology remains uninvestigated. Here, we report the first draft genome sequence of an E. tracheiphila strain isolated from an infected wild gourd ( Cucurbita pepo subsp. texana ) plant. The genome assembly consists of 7 contigs and includes a putative plasmid and at least 20 phage and prophage elements.

Background: Studies have suggested that exercise programs can reduce the incidence of noncontact injuries of the anterior cruciate ligament in female athletes. We conducted a two-year prospective study to assess the effects of a knee ligament injury prevention exercise program on the incidence of noncontact anterior cruciate ligament injuries in high-school female athletes. Methods: A prospective cohort design was used to study high-school female athletes (playing soccer, basketball, and volleyball) from fifteen schools (112 teams) for two consecutive seasons. The schools were divided into treatment and control groups. The treatment group participated in a plyometric-based exercise program twice a week throughout the season. Practice and game exposures and compliance with the exercise program were recorded on a weekly basis. Suspected noncontact anterior cruciate ligament injuries were confirmed on the basis of the history as well as at the time of surgery and/or with magnetic resonance imaging. Results: A total of 1439 athletes (862 in the control group and 577 in the treatment group) were monitored. There were six confirmed noncontact anterior cruciate ligament injuries: three in the treatment group, and three in the control group. The incidence of noncontact anterior cruciate ligament injuries per 1000 exposures was 0.167 in the treatment group and 0.078 in the control group, yielding an odds ratio of 2.05, which was not significant (p > 0.05). Conclusions: Our results suggest that a twenty-minute plyometric-based exercise program that focuses on the mechanics of landing from a jump and deceleration when running performed twice a week throughout the season will not reduce the rate of noncontact anterior cruciate ligament injuries in high-school female athletes. Level of Evidence: Therapeutic Level II. See Instructions to Authors for a complete description of levels of evidence.

Two recent methods for finding exact solutions to the Vlasov–Maxwell equations using Lie group theory are compared by the introduction of an ‘‘intermediate’’ approach. In the latter, the Lie group and general similarity solutions of the Vlasov equation are found through a method which treats independent and dependent variables as forms that are on an essentially equal footing. A Maxwell equation is then used to constrain the solutions further. The procedure is shown to illustrate a more general theorem that implies that the reduction of the number of variables in a set of equations through the use of canonical variables generated from the Lie group invariance of one equation in the set leads to the same solutions as are found by considering the invariance of the entire set.

The general Lie point transformation group and the associated reduced differential equations and similarity forms for the solutions are derived here for the coupled (nonlinear) Vlasov–Maxwell equations in one spatial dimension. The case of one species in a background is shown to admit a larger group than the multi-species case. Previous exact solutions are shown to be special cases of the above solutions, and many of the new solutions are found to constrain the form of the distribution function much more than, for example, the BGK solutions do. The individual generators of the Lie group are used to find the possible subgroups. Finally, a simple physical argument is given to show that the asymptotic solution (t→∞) for a one-species, one-dimensional plasma is one of the general similarity solutions.

Lie group point transformations applied to the one-dimensional Vlasov– Maxwell equations yield general similarity forms for the dependent and independent variables. One class of such solutions is seemingly like Bern-stein-Greene-Kruskal solutions in allowing a relatively free choice of electric field, but with a more complex time dependence. The phase trajectories of the particles are found here for both temporally damped and (possibly unphysical) growing electric fields in this class by numerical integration in the original and in transformed co-ordinates. The analysis, which includes an analytic consideration of phase-plane fixed (critical) points, shows the advantages of the new co-ordinates, and reveals qualitative features of the distribution function.

There is a region in any battery where the charges move in a direction opposite to that of the electric force on them. A ‘‘gravitational cell’’ is used to show that this motion is a diffusion analogous to that against pressure gradients in osmotic pressure situations. The driving mechanism for the diffusion is the existence of lower lying states in one region compared to an adjacent region, and it is relaxation into these low lying states that is the source of energy for the circuit.

The faint radio and emission line 'jet' outward from the northern boundary of the Crab Nebula which appears as a neat right cylinder is modelled here as the convected margin of a gas cloud that accidentially cast its shallow across the nearly ballistic flow of the stellar envelope ejected in the supernova explosion. It is shown that this model is consistent with known data on the jet, and that it accounts for the strikingly regular geometrical features in a natural way. In contrast, flow instability models do not easily result in so neat a cylinder.