23 research outputs found
Biology and control of currant lettuce aphid nasonovia ribisnigri
There is a consensus that the development of successful Integrated Pest Management strategies requires a detailed understanding of pest biology. In the case of the currant lettuce aphid (Nasonovia ribisnigri), an economically important pest aphid of
lettuce, sources of such information are limited. This study considers key aspects of N. ribisnigri biology which influence its control. In particular, it makes comparisons between biotypes which succumb to (wild-type) or overcome (resistance-breaking),
the host plant resistance (Nr-gene) in commercial lettuce cultivars.
Experiments on the effects of temperature and photoperiod on the development of N. ribisnigri showed no differences between wild-type and resistance-breaking biotypes. At low temperatures (5, 10 and 15ºC), wild-type biotypes developed to adulthood on resistant cultivars, indicating that the Nr-gene is temperature sensitive. A linear regression between development rate and temperature estimated a lower developmental threshold of around 4.7ºC. Nasonovia ribisnigri usually overwinters as a diapausing egg but overwintering nymphs/adults have been observed. In the laboratory eggs were obtained at 12ºC 13L:11D. Sequential sampling of eggs from the field suggested that diapause ended
between late January and early February. Post-diapause development was estimated to take <50 day-degrees using a LDT of 4.7°C. Nasonovia ribisnigri survived the winter as nymphs/adults on Veronica arvensis in the Midlands. Other weed species were suitable hosts in the labratory: Chichorium intybus, Crepis capillaris, Lapsana communis, Hieracium aurantiacum, Hieracium pilosella, Veronica spicata and Veronica officinalis. Field trials, using sequentially planted plots of lettuce, and applying 'exclusion' and
pesticidal treatments indicated that natural enemies and emigration regulate aphid populations in the summer and contribute to the mid-summer crash. A large-scale screen of 96 cultivars and wild relatives of lettuce identified new sources of resistance against wild-type and resistance-breaking biotypes.
Results from this study can be used to inform further development of an Integrated Pest Management strategy for this pest
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Solving her problems? Beyond the seductive appeal of specialist problem-solving courts for women offenders in England and Wales
At the nexus of the social and penal policy fields, problem-solving justice promises to punish offenders while working to address the complex issues that drive their law-breaking behaviour. Appealing to the left and right due to its dual focus on pragmatism and welfarism, the concept has floated in and out of political fashion for the past two decades. Recent years have heralded a renewed political interest in the approach, closely aligned to the Conservative government’s commitment to ‘transforming justice’. With a focus on empowerment and collaboration, the problem-solving model has much to offer women offenders in particular. Drawing on data from a large-scale study into the sentencing and punishment of women under the new probation arrangements, this article reveals a divergence of views on gender-specific courts among sentencers, probation officers and third sector workers. Moral concerns about up-tariffing sit alongside the practical barriers of government bureaucracy and hindering legislation. With data pertaining to effectiveness (rather than potential) still required, this article argues that specialist problem-solving courts for women present a risky strategy, however seductive their promise
Sleep Quality, Fatigue, and Quality of Life Among Teenage and Young Adult Cancer Survivors
Purpose: Teenage and young adult (TYA) cancer survivors experience a range of health-related problems during and beyond the active treatment period. This study examined associations between fatigue, sleep quality, and health-related quality of life (HRQOL) among TYA survivors.Methods: Self-reported data on sleep quality (Pittsburgh Sleep Quality Index), fatigue (Functional Assessment of Chronic Illness Therapy Fatigue), and HRQOL (EuroQoL-5) were gathered from United Kingdom TYA survivors between 13 and 24 years of age. TYA survivors were stratified into those on (n = 67) and off (n = 135) treatment. Linear regression analyses were used with HRQOL as the dependent variable to investigate potential associations. Fatigue and sleep were entered separately and together in the same model. Age at survey and diagnosis, gender, and ethnicity were included as covariates.Results: 85.07% of TYAs on and 62.69% of TYAs off treatment had sleep quality scores suggestive of clinically significant sleep disorders. 56.72% of TYAs on and 26.67% of TYAs off treatment reported clinically significant levels of fatigue. Strong independent associations between sleep (B = 0.05, 95% confidence intervals [CI] = 0.03–0.07, p < 0.001), fatigue (B = 0.02, 95% CI = 0.01–0.03, p < 0.001), and HRQOL were observed among TYA survivors on treatment. TYAs off treatment showed moderate to strong associations between sleep (B = 0.04, 95% CI = 0.02–0.05, p < 0.001) and fatigue (B = 0.02, 95% CI = 0.01–0.02, p < 0.001), and HRQOL, when examined separately. Sleep was not independently associated with HRQOL among TYAs off treatment (B = 0.01, 95% CI = −0.01 to 0.02, p = 0.296).Conclusion: The significant associations reported suggest that sleep quality and fatigue are potential modifiable factors associated with HRQOL. Further research is warranted to understand the direction of associations
Sleep Quality, Fatigue, and Quality of Life Among Teenage and Young Adult Cancer Survivors
Purpose: Teenage and young adult (TYA) cancer survivors experience a range of health-related problems during and beyond the active treatment period. This study examined associations between fatigue, sleep quality, and health-related quality of life (HRQOL) among TYA survivors.Methods: Self-reported data on sleep quality (Pittsburgh Sleep Quality Index), fatigue (Functional Assessment of Chronic Illness Therapy Fatigue), and HRQOL (EuroQoL-5) were gathered from United Kingdom TYA survivors between 13 and 24 years of age. TYA survivors were stratified into those on (n = 67) and off (n = 135) treatment. Linear regression analyses were used with HRQOL as the dependent variable to investigate potential associations. Fatigue and sleep were entered separately and together in the same model. Age at survey and diagnosis, gender, and ethnicity were included as covariates.Results: 85.07% of TYAs on and 62.69% of TYAs off treatment had sleep quality scores suggestive of clinically significant sleep disorders. 56.72% of TYAs on and 26.67% of TYAs off treatment reported clinically significant levels of fatigue. Strong independent associations between sleep (B = 0.05, 95% confidence intervals [CI] = 0.03–0.07, p < 0.001), fatigue (B = 0.02, 95% CI = 0.01–0.03, p < 0.001), and HRQOL were observed among TYA survivors on treatment. TYAs off treatment showed moderate to strong associations between sleep (B = 0.04, 95% CI = 0.02–0.05, p < 0.001) and fatigue (B = 0.02, 95% CI = 0.01–0.02, p < 0.001), and HRQOL, when examined separately. Sleep was not independently associated with HRQOL among TYAs off treatment (B = 0.01, 95% CI = −0.01 to 0.02, p = 0.296).Conclusion: The significant associations reported suggest that sleep quality and fatigue are potential modifiable factors associated with HRQOL. Further research is warranted to understand the direction of associations
Quantifying local rainfall dynamics and uncertain boundary conditions into a nested regional-local flood modeling system
[Abstract:] Inflow discharge and outflow stage estimates for hydraulic flood models are generally derived from river gauge data. Uncertainties in the measured inflow data and the neglect of rainfall-runoff contributions to the modeled domain downstream of the gauging locations can have a significant impact on these estimated “whole reach” inflows and consequently on flood predictions. In this study, a method to incorporate rating curve uncertainty and local rainfall-runoff dynamics into the predictions of a reach-scale flood model is proposed. The methodology is applied to the July 2007 floods of the River Severn in UK. Discharge uncertainty bounds are generated applying a nonparametric local weighted regression approach to stage-discharge measurements for two gauging stations. Measured rainfall downstream from these locations is used as input to a series of subcatchment regional hydrological model to quantify additional local inflows along the main channel. A regional simplified-physics hydraulic model is then applied to combine these contributions and generate an ensemble of discharge and water elevation time series at the boundaries of a local-scale high complexity hydraulic model. Finally, the effect of these rainfall dynamics and uncertain boundary conditions are evaluated on the local-scale model. Accurate prediction of the flood peak was obtained with the proposed method, which was only possible by resolving the additional complexity of the extreme rainfall contributions over the modeled area. The findings highlight the importance of estimating boundary condition uncertainty and local rainfall contributions for accurate prediction of river flows and inundation at regional scales.María Bermúdez gratefully acknowledges financial support from the Spanish Regional Government of Galicia (postdoctoral grant reference ED481B 2014/156-0). Gemma Coxon was supported by NERC MaRIUS: Managing the Risks, Impacts and Uncertainties of droughts and water Scarcity, grant NE/L010399/1. Jim Freer and Paul Bates by NERC Susceptibility of catchments to INTense RAinfall and flooding, grant NE/K00882X/1. A free version of the model LISFLOOD-FP is available for download at www.bristol.ac.uk/geography/research/hydrology/models/lisflood/. A free version of the model Iber is available for download at www.iberaula.es. The river cross-section data, the LiDAR digital elevation model and the gauging station rainfall, stage, flow and rating curve data of the presented case study are freely available from the Environment Agency ([email protected])Xunta de Galicia; ED481B 2014/156-0Inglaterra. University of Bristol; NE/L010399/1Inglaterra. University of Bristol; NE/K00882X/
Novel gene function revealed by mouse mutagenesis screens for models of age-related disease
Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss
Human and mouse essentiality screens as a resource for disease gene discovery
The identification of causal variants in sequencing studies remains a considerable challenge that can be partially addressed by new gene-specific knowledge. Here, we integrate measures of how essential a gene is to supporting life, as inferred from viability and phenotyping screens performed on knockout mice by the International Mouse Phenotyping Consortium and essentiality screens carried out on human cell lines. We propose a cross-species gene classification across the Full Spectrum of Intolerance to Loss-of-function (FUSIL) and demonstrate that genes in five mutually exclusive FUSIL categories have differing biological properties. Most notably, Mendelian disease genes, particularly those associated with developmental disorders, are highly overrepresented among genes non-essential for cell survival but required for organism development. After screening developmental disorder cases from three independent disease sequencing consortia, we identify potentially pathogenic variants in genes not previously associated with rare diseases. We therefore propose FUSIL as an efficient approach for disease gene discovery. Discovery of causal variants for monogenic disorders has been facilitated by whole exome and genome sequencing, but does not provide a diagnosis for all patients. Here, the authors propose a Full Spectrum of Intolerance to Loss-of-Function (FUSIL) categorization that integrates gene essentiality information to aid disease gene discovery
Adjunctive rifampicin for Staphylococcus aureus bacteraemia (ARREST): a multicentre, randomised, double-blind, placebo-controlled trial.
BACKGROUND: Staphylococcus aureus bacteraemia is a common cause of severe community-acquired and hospital-acquired infection worldwide. We tested the hypothesis that adjunctive rifampicin would reduce bacteriologically confirmed treatment failure or disease recurrence, or death, by enhancing early S aureus killing, sterilising infected foci and blood faster, and reducing risks of dissemination and metastatic infection. METHODS: In this multicentre, randomised, double-blind, placebo-controlled trial, adults (≥18 years) with S aureus bacteraemia who had received ≤96 h of active antibiotic therapy were recruited from 29 UK hospitals. Patients were randomly assigned (1:1) via a computer-generated sequential randomisation list to receive 2 weeks of adjunctive rifampicin (600 mg or 900 mg per day according to weight, oral or intravenous) versus identical placebo, together with standard antibiotic therapy. Randomisation was stratified by centre. Patients, investigators, and those caring for the patients were masked to group allocation. The primary outcome was time to bacteriologically confirmed treatment failure or disease recurrence, or death (all-cause), from randomisation to 12 weeks, adjudicated by an independent review committee masked to the treatment. Analysis was intention to treat. This trial was registered, number ISRCTN37666216, and is closed to new participants. FINDINGS: Between Dec 10, 2012, and Oct 25, 2016, 758 eligible participants were randomly assigned: 370 to rifampicin and 388 to placebo. 485 (64%) participants had community-acquired S aureus infections, and 132 (17%) had nosocomial S aureus infections. 47 (6%) had meticillin-resistant infections. 301 (40%) participants had an initial deep infection focus. Standard antibiotics were given for 29 (IQR 18-45) days; 619 (82%) participants received flucloxacillin. By week 12, 62 (17%) of participants who received rifampicin versus 71 (18%) who received placebo experienced treatment failure or disease recurrence, or died (absolute risk difference -1·4%, 95% CI -7·0 to 4·3; hazard ratio 0·96, 0·68-1·35, p=0·81). From randomisation to 12 weeks, no evidence of differences in serious (p=0·17) or grade 3-4 (p=0·36) adverse events were observed; however, 63 (17%) participants in the rifampicin group versus 39 (10%) in the placebo group had antibiotic or trial drug-modifying adverse events (p=0·004), and 24 (6%) versus six (2%) had drug interactions (p=0·0005). INTERPRETATION: Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S aureus bacteraemia. FUNDING: UK National Institute for Health Research Health Technology Assessment
Sun exposure among teenage and young adult cancer survivors in the United Kingdom
Skin cancers are a common form of second malignant neoplasm among teenage and young adult cancer survivors (TYACS). The Children's Oncology Group specifies that TYACS should adhere to safe sun practices and be screened for skin cancer annually. Cross-sectional self-report data collected by our group indicate over a third of TYACS (n = 229; mean age: 19.8 years) intentionally sunbathe, with many reporting sunburn. TYACS sunbathing, sunburn, and sunbed use are similar to the general population (P > 0.05). These data suggest TYACS require intervention to limit sun exposure and improve their sun safety habits.</p