Extended Sentinel Monitoring of Helicoverpa zea Resistance to Cry and Vip3Aa Toxins in Bt Sweet Corn: Assessing Changes in Phenotypic and Allele Frequencies of Resistance

Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020–2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) in H. zea populations and the range of resistance allele frequencies for Cry1Ab and Vip3Aa. The results revealed a widespread resistance to Cry1Ab, Cry2Ab2, and Cry1A.105 Cry toxins, with higher numbers of larvae surviving in Bt ears than in non-Bt ears at many trial locations. Depending on assumptions about the inheritance of resistance, allele frequencies for Cry1Ab ranged from 0.465 (dominant resistance) to 0.995 (recessive resistance). Although Vip3Aa provided high control efficacy against H. zea, the results show a notable increase in ear damage and a number of surviving older larvae, particularly at southern locations. Assuming recessive resistance, the estimated resistance allele frequencies for Vip3Aa ranged from 0.115 in the Gulf states to 0.032 at more northern locations. These findings indicate that better resistance management practices are urgently needed to sustain efficacy the of corn and cotton that produce Vip3Aa

Surface-wave imaging of the weakly-extended Malawi Rift from ambient-noise and teleseismic Rayleigh waves from onshore and lake-bottom seismometers

Located at the southernmost sector of the Western Branch of the East African Rift System, the Malawi Rift exemplifies an active, magma-poor, weakly extended continental rift. To investigate the controls on rifting, we image crustal and uppermost mantle structure beneath the region using ambient-noise and teleseismic Rayleigh-wave phase velocities between 9 and 100 s period. Our study includes six lake-bottom seismometers located in Lake Malawi (Nyasa), the first time seismometers have been deployed in any of the African rift lakes. Noise-levels in the lake are lower than that of shallow oceanic environments and allow successful application of compliance corrections and instrument orientation determination. Resulting phase-velocity maps reveal slow velocities primarily confined to Lake Malawi at short periods (T 25 s) a prominent low-velocity anomaly exists beneath the Rungwe Volcanic Province at the northern terminus of the rift basin. Estimates of phase-velocity sensitivity indicates these low velocities occur within the lithospheric mantle and potentially uppermost asthenosphere, suggesting that mantle processes may control the association of volcanic centers and the localization of magmatism. Beneath the main portion of the Malawi Rift, a modest reduction in velocity is also observed at periods sensitive to the crust and upper mantle, but these velocities are much higher than those observed beneath Rungwe

Effects of laterally wedged insoles on symptoms and disease progression in medial knee osteoarthritis: a protocol for a randomised, double-blind, placebo controlled trial

<p>Abstract</p> <p>Background</p> <p>Whilst laterally wedged insoles, worn inside the shoes, are advocated as a simple, inexpensive, non-toxic self-administered intervention for knee osteoarthritis (OA), there is currently limited evidence to support their use. The aim of this randomised, double-blind controlled trial is to determine whether laterally wedges insoles lead to greater improvements in knee pain, physical function and health-related quality of life, and slower structural disease progression as well as being more cost-effective, than control flat insoles in people with medial knee OA.</p> <p>Methods/Design</p> <p>Two hundred participants with painful radiographic medial knee OA and varus malalignment will be recruited from the community and randomly allocated to lateral wedge or control insole groups using concealed allocation. Participants will be blinded as to which insole is considered therapeutic. Blinded follow up assessment will be conducted at 12 months after randomisation. The outcome measures are valid and reliable measures recommended for OA clinical trials. Questionnaires will assess changes in pain, physical function and health-related quality-of-life. Magnetic resonance imaging will measure changes in tibial cartilage volume. To evaluate cost-effectiveness, participants will record the use of all health-related treatments in a log-book returned to the assessor on a monthly basis. To test the effect of the intervention using an intention-to-treat analysis, linear regression modelling will be applied adjusting for baseline outcome values and other demographic characteristics.</p> <p>Discussion</p> <p>Results from this trial will contribute to the evidence regarding the effectiveness of laterally wedged insoles for the management of medial knee OA.</p> <p>Trial registration</p> <p>ACTR12605000503628; NCT00415259.</p

Prehospital transdermal glyceryl trinitrate in patients with ultra-acute presumed stroke (RIGHT-2): an ambulance-based, randomised, sham-controlled, blinded, phase 3 trial

Background High blood pressure is common in acute stroke and is a predictor of poor outcome; however, large trials of lowering blood pressure have given variable results, and the management of high blood pressure in ultra-acute stroke remains unclear. We investigated whether transdermal glyceryl trinitrate (GTN; also known as nitroglycerin), a nitric oxide donor, might improve outcome when administered very early after stroke onset. Methods We did a multicentre, paramedic-delivered, ambulance-based, prospective, randomised, sham-controlled, blinded-endpoint, phase 3 trial in adults with presumed stroke within 4 h of onset, face-arm-speech-time score of 2 or 3, and systolic blood pressure 120 mm Hg or higher. Participants were randomly assigned (1:1) to receive transdermal GTN (5 mg once daily for 4 days; the GTN group) or a similar sham dressing (the sham group) in UK based ambulances by paramedics, with treatment continued in hospital. Paramedics were unmasked to treatment, whereas participants were masked. The primary outcome was the 7-level modified Rankin Scale (mRS; a measure of functional outcome) at 90 days, assessed by central telephone follow-up with masking to treatment. Analysis was hierarchical, first in participants with a confirmed stroke or transient ischaemic attack (cohort 1), and then in all participants who were randomly assigned (intention to treat, cohort 2) according to the statistical analysis plan. This trial is registered with ISRCTN, number ISRCTN26986053. Findings Between Oct 22, 2015, and May 23, 2018, 516 paramedics from eight UK ambulance services recruited 1149 participants (n=568 in the GTN group, n=581 in the sham group). The median time to randomisation was 71 min (IQR 45–116). 597 (52%) patients had ischaemic stroke, 145 (13%) had intracerebral haemorrhage, 109 (9%) had transient ischaemic attack, and 297 (26%) had a non-stroke mimic at the final diagnosis of the index event. In the GTN group, participants’ systolic blood pressure was lowered by 5·8 mm Hg compared with the sham group (p<0·0001), and diastolic blood pressure was lowered by 2·6 mm Hg (p=0·0026) at hospital admission. We found no difference in mRS between the groups in participants with a final diagnosis of stroke or transient ischaemic stroke (cohort 1): 3 (IQR 2–5; n=420) in the GTN group versus 3 (2–5; n=408) in the sham group, adjusted common odds ratio for poor outcome 1·25 (95% CI 0·97–1·60; p=0·083); we also found no difference in mRS between all patients (cohort 2: 3 [2–5]; n=544, in the GTN group vs 3 [2–5]; n=558, in the sham group; 1·04 [0·84–1·29]; p=0·69). We found no difference in secondary outcomes, death (treatment-related deaths: 36 in the GTN group vs 23 in the sham group [p=0·091]), or serious adverse events (188 in the GTN group vs 170 in the sham group [p=0·16]) between treatment groups. Interpretation Prehospital treatment with transdermal GTN does not seem to improve functional outcome in patients with presumed stroke. It is feasible for UK paramedics to obtain consent and treat patients with stroke in the ultraacute prehospital setting. Funding British Heart Foundation

Emotional and behavioral reactions to social undermining: A closer look at perceived offender motives

This study examined how perceptions of underlying offender motives affect victims' emotional and behavioral reactions toward their offender. Perceived offender motives of malice and greed were embedded in a cognition-emotion-behavior model based on theories of attribution, forgiveness and revenge, and tested in the context of social undermining. Findings suggested that victims distinguished between offender malice and greed, and that these attributions shaped subsequent emotional reactions, which in turn demonstrated independent relations with revenge, avoidance, and reconciliation.Motives Affect/emotion Social undermining Attribution Forgiveness Avoidance Anger Sympathy Revenge Generalizability External validity

Making Things Happen Through Challenging Goals: Leader Proactivity, Trust, And Business-Unit Performance

Building on decades of research on the proactivity of individual performers, this study integrates research on goal setting and trust in leadership to examine manager proactivity and business unit sales performance in one of the largest sales organizations in the United States. Results of a moderated-mediation model suggest that proactive senior managers establish more challenging goals for their business units (N = 50), which in turn are associated with higher sales performance. We further found that employees\u27 trust in the manager is a critical contingency variable that facilitates the relationship between challenging sales goals and subsequent sales performance. This research contributes to growing literatures on trust in leadership and proactivity by studying their joint effects at a district-unit level of analysis while identifying district managers\u27 tendency to set challenging goals as a process variable that helps translate their proactivity into the collective performance of their units. © 2013 American Psychological Association

Leader Humor As An Interpersonal Resource: Integrating Three Theoretical Perspectives

We integrate theoretical perspectives on humor to test the processes through which leader humor (LH) facilitates subordinate organizational citizenship behaviors (OCBs). In doing so, we argue that humor is a key interpersonal resource for leaders and derive our comprehensive model with logic from three individual-resource-related theories-social exchange theory, conservation of resources theory, and broaden-and-build theory. Leader-triggered positive emotion and subsequent social exchange, operationalized as leader-member exchange (LMX), functioned as key sequential mechanisms mediating the relationship between LH and subordinate OCBs. LH induced positive emotion in subordinates, which fostered high-quality LMX and, in turn, OCBs. Contrary to expectations, the stress relief explanation of LH was not supported. This research contributes to knowledge of humor in organizations, and particularly LH, as it is the first to establish a link between LH and OCBs and also represents the first integration and concurrent examination of three functions of humor. We additionally offer empirical contributions to the humor literature by providing a comprehensive test of prior conceptual arguments regarding mechanisms of LH and validating a measure of LH that can be used in future research. For LMX research, we draw attention to LH as an overlooked but important socioemotional resource for social exchange

How negative affectivity moderates the relationship between shocks, embeddedness and worker behaviors

We integrated the unfolding model of turnover, job embeddedness theory and affective events theory to build and test a model specifying the relationship between negative shocks, on-the-job embeddedness and important employee behaviors. The results showed that embeddedness mediates the relationship between negative shocks and job search behaviors as well as counterproductive work behaviors. The study further examines the role of dispositional influences on reactions to negative workplace shocks and how these reactions affect organizational citizenship behavior, counterproductive work behavior and job search behavior. Results indicated a moderated-mediation effect of negative affectivity on each of these outcomes