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BROWN marmorated stink bug, STINKBUGS, PARASITISM, PREDATION, and HEMIPTERA

Stink bugs, including Halyomorpha halys (Stål) and Nezara viridula (L.), are agricultural pests that feed on fruit in a variety of crops. Monitoring predation and parasitism of stink bug egg masses furthers our understanding of potential biological control tactics. However, best practices for laboratory and field assessments of parasitism and predation of egg masses require further attention. We carried out a series of laboratory and field experiments to test whether parasitism and predation for three types of sentinel H. halys egg masses, fresh, frozen, and refrigerated, varied in agricultural commodities. In addition, we asked if predation and parasitism differed between sentinel and naturally occurring H. halys and N. viridula egg masses in soybean. In the laboratory, more H. halys eggs were parasitized by Trissolcus euschisti (Ashmead) (Hymenoptera: Scelionidae) if they were frozen or refrigerated compared to fresh eggs. Similarly, in the field, parasitism was higher for frozen egg masses than fresh. In 2018 and 2019, H. halys natural egg masses had higher parasitism and lower predation compared to sentinel egg masses in soybean. In a paired field test during 2020 and 2021, there was no difference in parasitism between H. halys natural and sentinel eggs, but much higher incidence of parasitism was detected in natural N. viridula egg masses than sentinel eggs. Collecting natural egg masses is the best methodology for field assessment of parasitism of stink bug egg masses; however, if natural egg masses are not easily available, deploying refrigerated sentinel egg masses is a good alternative. [ABSTRACT FROM AUTHOR]

BROWN marmorated stink bug, STINKBUGS, FIELD crops, PHEROMONE traps, CROPS, HEMIPTERA, and COTTON

Stink bugs (Hemiptera: Pentatomidae), including the exotic Halyomorpha halys (Stål), Nezara viridula (L.), and other indigenous species, are pests that damage a variety of agricultural crops. At a study site in the southeastern United States, we measured the density of stink bug species and patterns of parasitism and predation on corn, cotton, and soybean and host trees in an adjacent woodline. We assessed parasitism and predation of naturally laid egg masses in crops and sentinel egg masses in host trees and used pheromone-baited traps to determine H. halys seasonal development. Overall, H. halys and N. viridula were the dominant bugs observed. Adult H. halys were first detected each year on trees, followed by corn, and then cotton and soybean, suggesting that trees served as a source of H. halys dispersing into crops. For H. halys , more nymphs were captured in soybean than in corn or cotton. For N. viridula , more adults were captured in corn and cotton than in soybean, and more nymphs were captured in corn during 2019 and 2021 than in 2020. Percentage parasitism of N. viridula egg masses (74.2%) was higher than than that for H. halys egg masses (54.3%). Accordingly, conservation biological control has the potential to enhance parasitism of indigenous stink bugs and H. halys in field crop agroecosystems. [ABSTRACT FROM AUTHOR]

STINKBUGS, BROWN marmorated stink bug, CARBON dioxide, FUMIGATION, ATMOSPHERIC carbon dioxide, HEMIPTERA, and DILUTION

BACKGROUND: The brown marmorated stink bug (BMSB), Halyomorpha halys, has caused significant agricultural damage to numerous hosts, so agricultural producers seek to limit its spread. Where established, BMSB can also cause substantial urban and commercial disturbance, as overwintering adults may seek refuge inside dwellings, covered spaces, vehicles, and consignments. Phytosanitary authorities are most concerned with the importation of 'hitchhiking' adults in this refugia, with certain countries requiring a quarantine treatment to mitigate risk. This study explores fumigation with ethyl formate, applied as 16.7% by mass dilution in carbon dioxide, for control of adult BMSB. RESULTS: The induction of diapause, to simulate overwintering physiology, resulted in 2‐ and 3‐fold increases in the tolerance of adults toward this ethyl formate fumigation at 10 ± 0.5 °C (x¯±2s) lasting for 8 and 12 h, respectively. However, a decreased tolerance (0.7‐fold) of diapausing specimens was observed for a 4‐h duration. Diapausing and nondiapausing adult BMSB can be controlled at the probit 9 level if the headspace concentration of ethyl formate, [EF], in the carbon dioxide mixture is maintained ≥7.68 mg L−1 for 12 h at 10 ± 0.5 °C (x¯±2s). If the duration is shortened to 4 h, [EF] must be maintained ≥14.73 mg L−1 over the course of fumigation. CONCLUSION: The toxicity of ethyl formate in this mixture can be distinct for different physiological states of the same life stage, as evidenced by a ca. 3‐fold increase in the Haber's z parameter for adult BMSB when in diapause. Respective to the physiological state of adults, this study identifies how the applied dose and/or treatment duration can be modulated (i.e. tuned) to ensure adequate toxicological efficacy toward BMSB infesting hosts or refuge at temperatures ca. >10 °C. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

PULMONARY embolism, CLINICAL prediction rules, NURSING home patients, PREDICTION models, VENOUS thrombosis, THROMBOEMBOLISM, and SYMPTOMS

Aims Risk stratification is used for decisions regarding need for imaging in patients with clinically suspected acute pulmonary embolism (PE). The aim was to develop a clinical prediction model that provides an individualized, accurate probability estimate for the presence of acute PE in patients with suspected disease based on readily available clinical items and D-dimer concentrations. Methods and results An individual patient data meta-analysis was performed based on sixteen cross-sectional or prospective studies with data from 28 305 adult patients with clinically suspected PE from various clinical settings, including primary care, emergency care, hospitalized and nursing home patients. A multilevel logistic regression model was built and validated including ten a priori defined objective candidate predictors to predict objectively confirmed PE at baseline or venous thromboembolism (VTE) during follow-up of 30 to 90 days. Multiple imputation was used for missing data. Backward elimination was performed with a P -value <0.10. Discrimination (c-statistic with 95% confidence intervals [CI] and prediction intervals [PI]) and calibration (outcome:expected [O:E] ratio and calibration plot) were evaluated based on internal-external cross-validation. The accuracy of the model was subsequently compared with algorithms based on the Wells score and D-dimer testing. The final model included age (in years), sex, previous VTE, recent surgery or immobilization, haemoptysis, cancer, clinical signs of deep vein thrombosis, inpatient status, D-dimer (in µg/L), and an interaction term between age and D-dimer. The pooled c-statistic was 0.87 (95% CI, 0.85–0.89; 95% PI, 0.77–0.93) and overall calibration was very good (pooled O:E ratio, 0.99; 95% CI, 0.87–1.14; 95% PI, 0.55–1.79). The model slightly overestimated VTE probability in the lower range of estimated probabilities. Discrimination of the current model in the validation data sets was better than that of the Wells score combined with a D-dimer threshold based on age (c-statistic 0.73; 95% CI, 0.70–0.75) or structured clinical pretest probability (c-statistic 0.79; 95% CI, 0.76–0.81). Conclusion The present model provides an absolute, individualized probability of PE presence in a broad population of patients with suspected PE, with very good discrimination and calibration. Its clinical utility needs to be evaluated in a prospective management or impact study. Registration PROSPERO ID 89366. [ABSTRACT FROM AUTHOR]

SESAME, BOTANICAL insecticides, INSECTICIDES, CARDIAC glycosides, INSECT mortality, HEMIPTERA, and EXTRACTS

A study was conducted to investigate the insecticidal potency of leaf and stem ethanolic extracts of white sesame (Sesamum indicum L.) on the pod-sucking bug (Clavigralla tomentosicollis Stal.) under laboratory conditions. Four different concentrations of the extracts (5.00, 10.00, 15.00 and 20.00 mg/l) of ethanolic extracts were prepared from the leaf and stem parts of the Sesame plant. Water and Cypermethrin were used as negative and positive controls. Fresh cowpea pods were treated with the various concentrations of the stem and leaf ethanolic extracts and the pod-sucking bugs were introduced into the jars containing the pods. The result obtained revealed significant differences (P≤0.05) in the effect of various concentrations in inducing mortality of the insects at different instars. The extracts were more effective in the first (1st) instars against the pod-sucking bugs. The activity is concentration dependent as it increases with increase in concentration of the extract. However, leaf ethanolic extract proved to be more effective. More so, the percentages of pods infested by the bugs were found to be lower among the 20.00 mg/l treated pods in both stem and leaf ethanolic extracts. The phytochemical result indicated the presence of certain phytochemicals such as alkaloids, carbohydrates, cardiac glycosides, diterpenoids, flavonoids, proteins, saponins, steroids, tannins and triterpenoids that were proved to be vital in the insecticidal activity of the extracts. Thus, the stem and leaf ethanolic extracts of sesame are effective botanical insecticides against C. tomentosicollis especially at 20.00 mg/l of the leaf extract. [ABSTRACT FROM AUTHOR]

HIGGS bosons, SCALAR field theory, SUPERSYMMETRY, STANDARD model (Nuclear physics), DARK matter, and MATHEMATICAL models

The goal of this report is to summarize the current situation and discuss possible search strategies for charged scalars, in non-supersymmetric extensions of the Standard Model at the LHC. Such scalars appear in Multi-Higgs-Doublet models, in particular in the popular Two-Higgs-Doublet model, allowing for charged and additional neutral Higgs bosons. These models have the attractive property that electroweak precision observables are automatically in agreement with the Standard Model at the tree level. For the most popular version of this framework, Model II, a discovery of a charged Higgs boson remains challenging, since the parameter space is becoming very constrained, and the QCD background is very high. We also briefly comment on models with dark matter which constrain the corresponding charged scalars that occur in these models. The stakes of a possible discovery of an extended scalar sector are very high, and these searches should be pursued in all conceivable channels, at the LHC and at future colliders. [ABSTRACT FROM AUTHOR]