Identification, Biology, Impacts, and Management of Stink Bugs (Hemiptera: Heteroptera: Pentatomidae) of Soybean and Corn in the Midwestern United States

Stink bugs (Hemiptera: Heteroptera: Pentatomidae) are an emerging threat to soybean and corn production in the midwestern United States. An invasive species, the brown marmorated stink bug, Halyomorpha halys (Sta° l), is spreading through the region. However, little is known about the complex of stink bug species associated with corn and soybean in the midwestern United States. In this region, particularly in the more northern states, stink bugs have historically caused only infrequent impacts to these crops. To prepare growers and agricultural professionals to contend with this new threat, we provide a review of stink bugs associated with soybean and corn in the midwestern United States. Descriptions and images of common stink bug species are provided as a diagnostic aid. The biologies and impacts of stink bugs to crops are discussed, with particular attention to differences among species. Based primarily on information from southern states, scouting, thresholds, and insecticide-based management of these pests are discussed. It is hoped that this review will provide stakeholders sufficient information for management of these pests, until more region-specific research can be performed on stink bugs in soybean and corn in the midwestern United States

Survival After Endovascular Aneurysm Sealing Compared With Endovascular Aneurysm Repair

Introduction Endovascular aneurysm sealing (EVAS) is a sac-filling device with a blunted systemic inflammatory response compared to conventional endovascular aneurysm repair (EVAR), with a suggested impact on all-cause mortality. This study compares mortality after both EVAS and EVAR. Materials and Methods This is a retrospective observational study including data from 2 centres, with ethical approval. Elective procedures on asymptomatic infrarenal aneurysms performed between January 2011 until April 2018 were enrolled. Laboratory values (serum creatinine, haemoglobin, white blood cell count, platelet count) were measured pre- and postoperatively and at 1 and 2 years, respectively. Mortality and cause of death were recorded during follow-up. Results A total of 564 patients were included (225 EVAS, 369 EVAR), after propensity score matching there were 207 patients in both groups. Baseline characteristics were similar, except for larger neck angulation and more pulmonary disease in the EVAR group. The median follow-up time was 49 (EVAS) and 44 (EVAR) months. No significant differences regarding creatinine and haemoglobin were observed. Preoperative white blood cell count was higher in the EVAR group (p=0.011), without significant differences during follow-up. Median platelet count was lower in the EVAR group preoperatively (p=0.001), but was significantly higher at 1 year follow-up (p=0.003). There were 43 deaths within the EVAS group (20.8%) and 52 within the EVAR group (25.1%) (p=0.293). Of these, 4 were aneurysm related (EVAS n=3, EVAR n=1; p=0.222) and 14 cardiovascular (EVAS n=6, EVAR n=8, p=0.845). For the EVAS cohort, survival was 95.5% at 1 year and 74.9% at 5 years. For the EVAR cohort, this was 93.3% at 1 year and 75.5% at 5 years. No significant differences were observed in causes of death. Conclusion This study showed comparable survival rates through 5 years between EVAS and EVAR with a tendency toward higher inflammatory response in the EVAR patients through the first 2 years

Constraints on the perturbed mutual motion in Didymos due to impact-induced deformation of its primary after the DART impact

Binary near-Earth asteroid (65803) Didymos is the target of the proposed NASA Double Asteroid Redirection Test (DART), part of the Asteroid Impact & Deflection Assessment (AIDA) mission concept. In this mission, the DART spacecraft is planned to impact the secondary body of Didymos, perturbing mutual dynamics of the system. The primary body is currently rotating at a spin period close to the spin barrier of asteroids, and materials ejected from the secondary due to the DART impact are likely to reach the primary. These conditions may cause the primary to reshape, due to landslides, or internal deformation, changing the permanent gravity field. Here, we propose that if shape deformation of the primary occurs, the mutual orbit of the system would be perturbed due to a change in the gravity field. We use a numerical simulation technique based on the full two-body problem to investigate the shape effect on the mutual dynamics in Didymos after the DART impact. The results show that under constant volume, shape deformation induces strong perturbation in the mutual motion. We find that the deformation process always causes the orbital period of the system to become shorter. If surface layers with a thickness greater than ~0.4 m on the poles of the primary move down to the equatorial region due to the DART impact, a change in the orbital period of the system and in the spin period of the primary will be detected by ground-based measurement.Comment: 8 pages, 7 figures, 2 tables, accepted for publication in MNRA

Determination of the nature of the Cu coordination complexes formed in the presence of NO and NH3 within SSZ-13

Ammonia-selective catalytic reduction (NH3-SCR) using Cu zeolites is a well-established strategy for the abatement of NOx gases. Recent studies have demonstrated that Cu is particularly active when exchanged into the SSZ-13 zeolite, and its location in either the 6r or 8r renders it an excellent model system for fundamental studies. In this work, we examine the interaction of NH3-SCR relevant gases (NO and NH3) with the Cu2+ centers within the SSZ-13 structure, coupling powder diffraction (PD), X-ray absorption spectroscopy (XAFS), and density functional theory (DFT). This combined approach revealed that, upon calcination, cooling and gas exposure Cu ions tend to locate in the 8r window. After NO introduction, Cu-ions are seen to coordinate to two framework oxygens and one NO molecule, resulting in a bent Cu-nitrosyl complex with a Cu-N-O bond angle of similar to 150 degrees. Whilst Cu seems to be partially reduced/changed in coordination state, NO is partially oxidized. On exposure to NH3 while the PD data suggest the Cu2+ ion occupies a similar position, simulation and XAFS pointed toward the formation of a Jahn-Teller distorted hexaamine complex [Cu(NH3)(6)](2+) in the center of the cha cage. These results have important implications in terms of uptake and storage of these reactive gases and potentially for the mechanisms involved in the NH3-SCR process

Spatial Patterns and Sequential Sampling Plans for Estimating Densities of Stink Bugs (Hemiptera: Pentatomidae) in Soybean in the North Central Region of the United States

Stink bugs are an emerging threat to soybean (Fabales: Fabaceae) in the North Central Region of the United States. Consequently, region-specific scouting recommendations for stink bugs are needed. The aim of this study was to characterize the spatial pattern and to develop sampling plans to estimate stink bug population density in soybean fields. In 2016 and 2017, 125 fields distributed across nine states were sampled using sweep nets. Regression analyses were used to determine the effects of stink bug species [Chinavia hilaris (Say) (Hemiptera: Pentatomidae) and Euschistus spp. (Hemiptera: Pentatomidae)], life stages (nymphs and adults), and field locations (edge and interior) on spatial pattern as represented by variance–mean relationships. Results showed that stink bugs were aggregated. Sequential sampling plans were developed for each combination of species, life stage, and location and for all the data combined. Results for required sample size showed that an average of 40–42 sample units (sets of 25 sweeps) would be necessary to achieve a precision of 0.25 for stink bug densities commonly encountered across the region. However, based on the observed geographic gradient of stink bug densities, more practical sample sizes (5–10 sample units) may be sufficient in states in the southeastern part of the region, whereas impractical sample sizes (\u3e100 sample units) may be required in the northwestern part of the region. Our findings provide research-based sampling recommendations for estimating densities of these emerging pests in soybean

Effective population size of Anopheles funestus chromosomal forms in Burkina Faso

BACKGROUND: As Anopheles funestus is one of the principal Afro-tropical malaria vectors, a more complete understanding of its population structure is desirable. In West and Central Africa, An. funestus population structure is complicated by the coexistence of two assortatively mating chromosomal forms. Effective population size (N(e)) is a key parameter in understanding patterns and levels of intraspecific variation, as it reflects the role of genetic drift. Here, N(e )was estimated from both chromosomal forms, Kiribina and Folonzo, in Burkina Faso. METHODS: Short-term N(e )was estimated by evaluating variation at 16 microsatellite loci across temporal samples collected annually from 2000–2002. Estimates were based on standardized variance in allele frequencies or a maximum likelihood method. Long-term N(e )was estimated from genetic diversity estimates using mtDNA sequences and microsatellites. RESULTS: For both forms, short-term and long-term N(e )estimates were on the order of 10(3 )and 10(5), respectively. Long-term N(e )estimates were larger when based on loci from chromosome 3R (both inside and outside of inversions) than loci outside of this arm. CONCLUSION: N(e )values indicate that An. funestus is not subject to seasonal bottlenecks. Though not statistically different because of large and overlapping confidence intervals, short-term N(e )estimates were consistently smaller for Kiribina than Folonzo, possibly due to exploitation of different breeding sites: permanent for Folonzo and intermittent for Kiribina. The higher long-term N(e )estimates on 3R, the arm carrying the two inversions mainly responsible for defining the chromosomal forms, give natural selection broader scope and merit further study

Identification of evolutionarily conserved non-AUG-initiated N-terminal extensions in human coding sequences

In eukaryotes, it is generally assumed that translation initiation occurs at the AUG codon closest to the messenger RNA 5′ cap. However, in certain cases, initiation can occur at codons differing from AUG by a single nucleotide, especially the codons CUG, UUG, GUG, ACG, AUA and AUU. While non-AUG initiation has been experimentally verified for a handful of human genes, the full extent to which this phenomenon is utilized—both for increased coding capacity and potentially also for novel regulatory mechanisms—remains unclear. To address this issue, and hence to improve the quality of existing coding sequence annotations, we developed a methodology based on phylogenetic analysis of predicted 5′ untranslated regions from orthologous genes. We use evolutionary signatures of protein-coding sequences as an indicator of translation initiation upstream of annotated coding sequences. Our search identified novel conserved potential non-AUG-initiated N-terminal extensions in 42 human genes including VANGL2, FGFR1, KCNN4, TRPV6, HDGF, CITED2, EIF4G3 and NTF3, and also affirmed the conservation of known non-AUG-initiated extensions in 17 other genes. In several instances, we have been able to obtain independent experimental evidence of the expression of non-AUG-initiated products from the previously published literature and ribosome profiling data

Weekly Survivorship Curves of Soybean Aphid Biotypes 1 and 4 on Insecticidal Seed-Treated Soybean

Thiamethoxam, an insecticide used in soybean seed treatments, effectively suppresses soybean aphids (Aphis glycines) Matsumura (Hemiptera: Aphididae) for a short time after planting. However, exactly when and how quickly soybean aphid populations could increase is unknown. Likewise, we lack data on virulent soybean aphid biotypes (that can overcome soybean resistance) when fed on seed-treated soybean. Determining the survival of soybean aphids over time on insecticidal seed-treated soybean is critical for improving soybean aphid management and may provide insights to manage aphid virulence to aphid resistant-soybean. In greenhouse and field experiments, aphid-susceptible soybean plants (with and without an insecticidal seed treatment) were infested at 7, 14, 21, 28, 35, and 42 days after planting (DAP). We compared aphid survival among biotypes 1 (avirulent) and 4 (virulent) and insecticide treatment 72 h after infestation. We also measured thiamethoxam concentrations in plant tissue using liquid chromatography-tandem mass spectrometry. As expected, soybean aphid survival was significantly lower on seed-treated soybean up to 35 DAP for both biotypes, which correlates with the decrease of thiamethoxam in the plant over time. Moreover, we found no significant difference between avirulent and virulent biotype survivorship on insecticidal seed-treated soybean plants, although we did find significantly greater survival for the virulent biotype compared with the avirulent biotype on untreated soybean in the field. In conclusion, our study further characterized the relative short duration of seed treatment effectiveness on soybean aphid and showed that survivorship of virulent aphids on seed-treated soybean is similar to avirulent aphids

Metallic 1T Phase, 3d1 Electronic Configuration and Charge Density Wave Order in Molecular Beam Epitaxy Grown Monolayer Vanadium Ditelluride.

We present a combined experimental and theoretical study of monolayer vanadium ditelluride, VTe2, grown on highly oriented pyrolytic graphite by molecular-beam epitaxy. Using various in situ microscopic and spectroscopic techniques, including scanning tunneling microscopy/spectroscopy, synchrotron X-ray and angle-resolved photoemission, and X-ray absorption, together with theoretical analysis by density functional theory calculations, we demonstrate direct evidence of the metallic 1T phase and 3d1 electronic configuration in monolayer VTe2 that also features a (4 × 4) charge density wave order at low temperatures. In contrast to previous theoretical predictions, our element-specific characterization by X-ray magnetic circular dichroism rules out a ferromagnetic order intrinsic to the monolayer. Our findings provide essential knowledge necessary for understanding this interesting yet less explored metallic monolayer in the emerging family of van der Waals magnets