Susceptibility of the Cowpea Aphid (Hemiptera: Aphididae) to Widely Used Insecticides in Australia.

Globally, 27 aphid species have evolved resistance to almost 100 insecticide active ingredients. A proactive approach to resistance management in pest aphids is needed; this should include risk analysis, followed by regular baseline susceptibility assays for species deemed at high risk of evolving resistance. The cowpea aphid (Aphis craccivora Koch) has evolved insecticide resistance to multiple insecticides outside Australia and was recently identified as a high-risk species in Australia. In this study, we generated toxicity data against four insecticides (representing four unique chemical Mode of Action groups) for populations of A. craccivora collected across Australia. Alpha-cypermethrin was the most toxic chemical to A. craccivora in leaf-dip laboratory bioassays with an average LC50 value across nine populations of 0.008 mg a.i./L, which was significantly lower than dimethoate (1.17 mg a.i./L) and pirimicarb (0.89 mg a.i./L). Small, but significant, differences in sensitivity were detected in some populations against pirimicarb and dimethoate, whereas responses to alpha-cypermethrin and imidacloprid were not significantly different across all aphid populations examined in this study. For all insecticides, the field rate controlled 100% of individuals tested. The data generated will be important for future monitoring of insecticide responses of A. craccivora. Proactive management, including increased reliance on non-chemical pest management approaches and routine insecticide baseline sensitivity studies, is recommended for A. craccivora.

Mechanisms and Points of Control in the Spread of Inflammation: A Mathematical Investigation.

Understanding the mechanisms that control the body's response to inflammation is of key importance, due to its involvement in myriad medical conditions, including cancer, arthritis, Alzheimer's disease and asthma. While resolving inflammation has historically been considered a passive process, since the turn of the century the hunt for novel therapeutic interventions has begun to focus upon active manipulation of constituent mechanisms, particularly involving the roles of apoptosing neutrophils, phagocytosing macrophages and anti-inflammatory mediators. Moreover, there is growing interest in how inflammatory damage can spread spatially due to the motility of inflammatory mediators and immune cells. For example, impaired neutrophil chemotaxis is implicated in causing chronic inflammation under trauma and in ageing, while neutrophil migration is an attractive therapeutic target in ailments such as chronic obstructive pulmonary disease. We extend an existing homogeneous model that captures interactions between inflammatory mediators, neutrophils and macrophages to incorporate spatial behaviour. Through bifurcation analysis and numerical simulation, we show that spatially inhomogeneous outcomes can present close to the switch from bistability to guaranteed resolution in the corresponding homogeneous model. Finally, we show how aberrant spatial mechanisms can play a role in the failure of inflammation to resolve and discuss our results within the broader context of seeking novel inflammatory treatments.

A numerical simulation of neural fields on curved geometries.

Despite the highly convoluted nature of the human brain, neural field models typically treat the cortex as a planar two-dimensional sheet of ne;urons. Here, we present an approach for solving neural field equations on surfaces more akin to the cortical geometries typically obtained from neuroimaging data. Our approach involves solving the integral form of the partial integro-differential equation directly using collocation techniques alongside efficient numerical procedures for determining geodesic distances between neural units. To illustrate our methods, we study localised activity patterns in a two-dimensional neural field equation posed on a periodic square domain, the curved surface of a torus, and the cortical surface of a rat brain, the latter of which is constructed using neuroimaging data. Our results are twofold: Firstly, we find that collocation techniques are able to replicate solutions obtained using more standard Fourier based methods on a flat, periodic domain, independent of the underlying mesh. This result is particularly significant given the highly irregular nature of the type of meshes derived from modern neuroimaging data. And secondly, by deploying efficient numerical schemes to compute geodesics, our approach is not only capable of modelling macroscopic pattern formation on realistic cortical geometries, but can also be extended to include cortical architectures of more physiological relevance. Importantly, such an approach provides a means by which to investigate the influence of cortical geometry upon the nucleation and propagation of spatially localised neural activity and beyond. It thus promises to provide model-based insights into disorders like epilepsy, or spreading depression, as well as healthy cognitive processes like working memory or attention.

Fetal head position and perineal distension associated with the use of the BD Odon Device™ in operative vaginal birth: a simulation study.

OBJECTIVE: To investigate (1) the placement of the BD Odon Device on the model fetal head and (2) perineal distention during simulated operative vaginal births conducted with the BD Odon Device. DESIGN: Observational simulation study. SETTING: North Bristol NHS Trust, UK. POPULATION OR SAMPLE: Four hundred and forty simulated operative vaginal births. METHODS: Three bespoke fetal mannequins were developed to represent (1) bi-parietal diameter of the 50th centile at term, (2) bi-parietal diameter at the 5th centile at term, and (3) 50th centile head with 2 cm of caput. Siting of the BD Odon Device on model heads was determined before and after 400 simulated operative vaginal births. Variables were analysed to determine their effect on device siting and movement during birth. The fetal mannequins were placed inside a maternal mannequin and the BD Odon Device was placed around the fetal head as per the instructions for use. The location of the air cuff was determined before and after the head was delivered. Perineal distension was determined by recording maximum perineal distention during a simulated operative vaginal birth using the same procedure, as well as scenarios employing an inappropriately non-deflated air cuff (for the BD Odon Device), the Kiwi ventouse and non-rotational forceps. MAIN OUTCOME MEASURES: Site and displacement during birth of the BD Odon Device on a model head. Maximal perineal distension during birth. RESULTS: The BD Odon Device was reliably sited in a standard over the fetal head position (approximately 40 mm above the fetal chin) for all stations, head sizes and positions with no significant displacement. In occipito-posterior births, compared with occipito-anterior or transverse, the BD Odon Device routinely sited further down the fetal head (toward the chin). The BD Odon Device was not associated with more perineal distension compared with forceps or Kiwi ventouse (respectively 21, 26 and 21 mm at posterior fourchette). CONCLUSIONS: The BD Odon Device reliably sited over a safe area of the fetal head in 400 simulated births representative of clinical practice. The BD Odon Device generates similar levels of perineal distension compared with Kiwi ventouse when used correctly. TWEETABLE ABSTRACT: Location of the BD Odon Device on a fetal head in simulation.

Design and development of the BD Odon DeviceTM : a human factors evaluation process.

OBJECTIVE: To (1) determine how intended users interact with and use the BD Odon Device in simulation, (2) use these findings to alter progressively the design of the BD Odon Device and (3) validate that these changes have improved the ability of practitioners to use the BD Odon Device. DESIGN: Human factors evaluation study. SETTING: Simulation suite designed to mimic delivery room. POPULATION OR SAMPLE: Three hundred and ninety simulated operative births, performed by 100 practising clinicians. METHODS: Simulated operative vaginal births performed using the BD Odon Device and the device Instructions for use were subjected to three formative human factors evaluations and one human factors validation test. Following each evaluation, findings were reviewed and the design of the BD Odon Device and Instructions for use were modified. MAIN OUTCOME MEASURES: Successful performance of an operative vaginal birth using the BD Odon Device in accordance with provided training and Instructions for use. RESULTS: Using version two of the BD Odon Device, and following exposure to face-to-face training and written instructions, 25% of accouchers were able successfully to perform a simulated operative vaginal birth. In the final evaluation, following device design and training material alterations, all accouchers were able successfully to perform a simulated operative vaginal birth using version four of the BD Odon Device. CONCLUSIONS: Human factors evaluations have enabled a multi-professional device and training materials design team to alter the design of the BD Odon Device and the Instructions for use in an evidence-based fashion. This process has resulted in a device which has a predictable and likely safe pattern of use. TWEETABLE ABSTRACT: Human Factors evaluations help make the BD Odon Device safe and usable for clinical practice.

Pressure and traction on a model fetal head and neck associated with the use of forceps, Kiwi™ ventouse and the BD Odon Device™ in operative vaginal birth: a simulation study.

OBJECTIVE: To determine the pressure and traction forces exerted on a model fetal head by the BD Odon Device, forceps and Kiwi ventouse during simulated births. DESIGN: Simulation study. SETTING: Simulated operative vaginal birth. POPULATION OR SAMPLE: Eighty-four simulated operative vaginal births. METHODS: A bespoke fetal mannequin with pressure sensors around the head and strain gauge across the neck was used to investigate pressure applied over the head, and traction across the neck during 84 simulated births using the BD Odon Device, non-rotational forceps and Kiwi ventouse. MAIN OUTCOME MEASURES: Peak pressure on the fetal face and lateral aspects of the head during correct use of the BD Odon Device and forceps. Peak pressure on orbits and neck during misplacement of the BD Odon Device and forceps. Peak traction force generated until instrument failure using the BD Odon Device, forceps and Kiwi ventouse. RESULTS: When correctly sited and using 80 kPa inflation pressure on the cuff, the BD Odon Device generated a lower peak pressure on the fetal head than forceps (83 versus 146 kPa). When instruments were purposefully misplaced over the orbits, the BD Odon Device generated a lower peak pressure on the orbits compared with forceps (70 versus 123 kPa). When purposefully misplaced over the neck, the BD Odon Device, compared with forceps, generated a greater peak pressure on the anterio-lateral aspect of the neck (56 versus 17 kPa) and a lower peak pressure on the posterior aspect of the neck (76 versus 93 kPa) than forceps. In cases of true cephalic disproportion, the BD Odon Device 'popped-off' at a lower traction force than did forceps (208 versus 270 N). CONCLUSIONS: In simulated assisted vaginal birth with correctly placed instruments, the peak pressure exerted on the fetal head by a BD Odon Device is lower than the pressure exerted by non-rotational forceps. In cases in which delivery of the fetal head is not possible due to cephalo-pelvic disproportion, lower traction forces could be applied using the BD Odon Device than with forceps before the procedure was abandoned due to device failure. TWEETABLE ABSTRACT: BD Odon Device exerts less pressure on a model fetal head than forceps, but more than Kiwi ventouse.

Prevention of brachial plexus injury-12 years of shoulder dystocia training: an interrupted time-series study.

OBJECTIVE: To investigate management and outcomes of incidences of shoulder dystocia in the 12 years following the introduction of an obstetric emergencies training programme. DESIGN: Interrupted time-series study comparing management and neonatal outcome of births complicated by shoulder dystocia over three 4-year periods: (i) Pre-training (1996-99), (ii) Early training (2001-04), and (iii) Late training (2009-12). SETTING: Southmead Hospital, Bristol, UK, with approximately 6000 births per annum. POPULATION: Infants and their mothers who experienced shoulder dystocia. METHOD: A bi-monthly multi-professional 1-day intrapartum emergencies training course, that included a 30-minute practical session on shoulder dystocia management, commenced in 2000. MAIN OUTCOMES: Neonatal morbidity (brachial plexus injury, humeral fracture, clavicular fracture, 5-minute Apgar score <7) and documented management of shoulder dystocia (resolution manoeuvres performed, traction applied, head-to-body delivery interval). RESULTS: Compliance with national guidance improved with continued training. At least one recognised resolution manoeuvre was used in 99.8% (561/562) of cases of shoulder dystocia in the late training period, demonstrating a continued improvement from 46.3% (150/324, P < 0.001) pre-training, and 92% (241/262, P < 0.001) in the early training period. In parallel there was reduction in the brachial plexus injury at birth (24/324 [7.4%, P < 0.01], pre-training, 6/262 [2.3%] early training, and 7/562 [1.3%] late training. CONCLUSIONS: There are significant benefits to long-term, embedded training programmes with improvements in both management and outcomes. A decade after the introduction of training there were no cases of brachial plexus injury lasting over 12 months in 562 cases of shoulder dystocia.

Adaptation and implementation of local maternity dashboards in a Zimbabwean hospital to drive clinical improvement.

PROBLEM: The Commission on Information and Accountability for Women's and Children's Health of the World Health Organization (WHO) reported that national health outcome data were often of questionable quality and "not timely enough for practical use by health planners and administrators". Delayed reporting of poor-quality data limits the ability of front-line staff to identify problems rapidly and make improvements. APPROACH: Clinical "dashboards" based on locally available data offer a way of providing accurate and timely information. A dashboard is a simple computerized tool that presents a health facility's clinical data graphically using a traffic-light coding system to alert front-line staff about changes in the frequency of clinical outcomes. It provides rapid feedback on local outcomes in an accessible form and enables problems to be detected early. Until now, dashboards have been used only in high-resource settings. LOCAL SETTING: An overview maternity dashboard and a maternal mortality dashboard were designed for, and introduced at, a public hospital in Zimbabwe. A midwife at the hospital was trained to collect and input data monthly. RELEVANT CHANGES: Implementation of the maternity dashboards was feasible and 28 months of clinical outcome data were summarized using common computer software. Presentation of these data to staff led to the rapid identification of adverse trends in outcomes and to suggestions for actions to improve health-care quality. LESSONS LEARNT: Implementation of maternity dashboards was feasible in a low-resource setting and resulted in actions that improved health-care quality locally. Active participation of hospital management and midwifery staff was crucial to their success.

The United Kingdom public health response to an imported laboratory confirmed case of a novel coronavirus in September 2012.

On 22 September 2012, a novel coronavirus, very closely related to that from a fatal case in Saudi Arabia three months previously, was detected in a previously well adult transferred to intensive care in London from Qatar with severe respiratory illness. Strict respiratory isolation was instituted. Ten days after last exposure, none of 64 close contacts had developed severe disease, with 13 of 64 reporting mild respiratory symptoms. The novel coronavirus was not detected in 10 of 10 symptomatic contacts tested.

Tuberculosis and HIV co-infection in healthcare workers in England and Wales, 1999-2005.

This study used linked national tuberculosis (TB) and HIV surveillance data to investigate recent trends and factors associated with HIV co-infection (TB-HIV) in healthcare workers (HCWs) with TB in England and Wales. Methods applied were the χ2 trend test and logistic regression. Overall 14% (231/1627) of HCWs with TB were co-infected with HIV, increasing from 8% in 1999 to 14% in 2005 (P<0·001). Most (78%) HCWs were non-UK born and 74% of these developed TB ⩾2 years post-entry. Being born in Sub-Saharan Africa was an independent predictor for TB-HIV, especially for female HCWs (odds ratio 66·5, 95% confidence interval 16·3-271·1), who also had a lower median CD4 count than other co-infected women (106/mm3, interquartile range 40-200, P<0·01). Voluntary HIV testing of new HCWs should be encouraged as an opportunity for early diagnosis. Post-entry, a high index of clinical suspicion for TB in those most at risk remains important.

Practical simulation training for maternity care--where we are and where next.

Improving maternal and perinatal care is a global priority. Practical simulation training for maternity care might prevent many of these deaths. There have been numerous evaluation studies published on the effectiveness of simulation training for obstetric emergencies, with increasing evidence that it is associated with improvement in clinical outcomes. Evidence has begun to move from subjective assessment of participants' experiences towards objective assessment of clinical outcomes. However, the results are not entirely consistent and, at present, all of the evidence associating training with improvements in clinical outcomes relates to neonatal outcomes. This review summarises recent progress in the evaluation of the effectiveness of simulation training for maternity care in both high- and low-resource settings, and presents a vision for ensuring that practical simulation training for maternity care can become an effective tool to reduce global maternal and perinatal morbidity and mortality.

Clinical efficiency in a simulated emergency and relationship to team behaviours: a multisite cross-sectional study.

OBJECTIVE: To identify specific aspects of teamworking associated with greater clinical efficiency in simulated obstetric emergencies. DESIGN: Cross-sectional secondary analysis of video recordings from the Simulation & Fire-drill Evaluation (SaFE) randomised controlled trial. SETTING: Six secondary and tertiary maternity units. SAMPLE: A total of 114 randomly selected healthcare professionals, in 19 teams of six members. METHODS: Two independent assessors, a clinician and a language communication specialist identified specific teamwork behaviours using a grid derived from the safety literature. MAIN OUTCOME MEASURES: Relationship between teamwork behaviours and the time to administration of magnesium sulfate, a validated measure of clinical efficiency, was calculated. RESULTS: More efficient teams were likely to (1) have stated (recognised and verbally declared) the emergency (eclampsia) earlier (Kendall's rank correlation coefficient τ(b) = -0.53, 95% CI from -0.74 to -0.32, P=0.004); and (2) have managed the critical task using closed-loop communication (task clearly and loudly delegated, accepted, executed and completion acknowledged) (τ(b) = 0.46, 95% CI 0.17-0.74, P=0.022). Teams that administered magnesium sulfate within the allocated time (10 minutes) had significantly fewer exits from the labour room compared with teams who did not: a median of three (IQR 2-5) versus six exits (IQR 5-6) (P=0.03, Mann-Whitney U-test). CONCLUSIONS: Using administration of an essential drug as a valid surrogate of team efficiency and patient outcome after a simulated emergency, we found that more efficient teams were more likely to exhibit certain team behaviours relating to better handover and task allocation.

Network analysis detects changes in the contralesional hemisphere following stroke.

Changes in brain structure occur in remote regions following focal damage such as stroke. Such changes could disrupt processing of information across widely distributed brain networks. We used diffusion MRI tractography to assess connectivity between brain regions in 9 chronic stroke patients and 18 age-matched controls. We applied complex network analysis to calculate 'communicability', a measure of the ease with which information can travel across a network. Clustering individuals based on communicability separated patient and control groups, not only in the lesioned hemisphere but also in the contralesional hemisphere, despite the absence of gross structural pathology in the latter. In our highly selected patient group, lesions were localised to the left basal ganglia/internal capsule. We found reduced communicability in patients in regions surrounding the lesions in the affected hemisphere. In addition, communicability was reduced in homologous locations in the contralesional hemisphere for a subset of these regions. We interpret this as evidence for secondary degeneration of fibre pathways which occurs in remote regions interconnected, directly or indirectly, with the area of primary damage. We also identified regions with increased communicability in patients that could represent adaptive, plastic changes post-stroke. Network analysis provides new and powerful tools for understanding subtle changes in interactions across widely distributed brain networks following stroke.

Differential recruitment of nuclear receptor coregulators in ligand-dependent transcriptional repression by estrogen receptor-α.

Estrogen receptors (ERs) are normally expressed in breast tissues and mediate hormonal functions during development and in female reproductive physiology. In the majority of breast cancers, ERs are involved in regulating tumor cell proliferation and serve as prognostic markers and therapeutic targets in the management of hormone-dependent tumors. At the molecular level, ERs function as ligand-dependent transcription factors and activate target-gene expression following hormone stimulation. Recent transcriptomic and whole-genome-binding studies suggest, however, that ligand-activated ERs can also repress the expression of a significant subset of target genes. To characterize the molecular mechanisms of transcriptional repression by ERs, we examined recruitment of nuclear receptor coregulators, histone modifications and RNA polymerase II docking at ER-binding sites and cis-regulatory regions adjacent to repressed target genes. Moreover, we utilized gene expression data from patient samples to determine potential roles of repressed target genes in breast cancer biology. Results from these studies indicate that nuclear receptor corepressor recruitment is a key feature of ligand-dependent transcriptional repression by Ers, and some repressed target genes are associated with disease progression and response to endocrine therapy. These findings provide preliminary insights into a novel aspect of the molecular mechanisms of ER functions and their potential roles in hormonal carcinogenesis and breast cancer biology.

More to teamwork than knowledge, skill and attitude.

OBJECTIVE: To assess whether team performance in simulated eclampsia is related to the knowledge, skills and attitudes of individual team members. DESIGN: Cross-sectional analysis of data from the Simulation and Fire Drill Evaluation randomised controlled trial. SETTING: Six secondary and tertiary maternity units in south-west England. PARTICIPANTS: One hundred and fourteen maternity professionals in 19 teams of six members; one senior and one junior obstetrician; two senior and two junior midwives. METHODS: We validated a team performance ranking scheme with respect to magnesium administration (Magnesium Administration Rank, MAR) by expert consensus (face validity) and correlation with clinical measures (construct validity). We tested for correlation between MAR and measures of knowledge, skills and attitudes. MAIN OUTCOME MEASURES: Correlation between team performance (MAR) and scores in validated multiple-choice questionnaires (MCQs) (knowledge), a measure of individual manual skill to manage an obstetric emergency (skill) and scores in a widely used teamwork/safety attitude questionnaire (attitude). RESULTS: There was no relationship between team performance and cumulative individual MCQs, skill or teamwork/safety attitude scores. CONCLUSIONS: The knowledge, manual skills and attitudes of the individuals comprising each team, measured by established methods, did not correlate in this study with the team's clinical efficiency in the management of simulated eclampsia. The inference is that unidentified characteristic(s) play a crucial part in the efficiency of teams managing emergencies. Any emphasis of training programmes to promote individual knowledge, skills and attitudes alone may have to be re-examined. This highlights a need to understand what makes a team efficient in dealing with clinical emergencies.

Estimating tuberculosis case detection rate in resource-limited countries: a capture-recapture study in Egypt.

SETTING: Most countries endemic and highly endemic for tuberculosis (TB) still do not have reliable TB surveillance systems. Indirect estimation of TB incidence is needed to monitor the performance of the National Tuberculosis Programme (NTP) in the context of the World Health Organization implementation and impact targets for TB control. OBJECTIVE: To estimate the case detection rate (CDR) of all TB cases and sputum smear-positive TB cases in Egypt in 2007. METHODS: Record linkage and three-source capture-recapture analysis of data collected through active prospective longitudinal surveillance within the public and private non-NTP sector in four Egyptian governorates selected by stratified cluster random sampling. RESULTS: For all TB cases, the estimated CDR of NTP surveillance and completeness of case ascertainment after record linkage was respectively 55% (95%CI 46-68) and 62% (95%CI 52-77). For sputum smear-positive TB cases, these proportions were respectively 66% (95%CI 55-75) and 72% (95%CI 60-82). CONCLUSION: This pilot study shows that representative sampling, prospective surveillance in the non-NTP sector, record linkage and capture-recapture analysis can improve CDR estimation. For global, standardised and reliable use, this methodology should be further developed. Until then, all resource-limited countries should strengthen their national surveillance systems in the context of the Stop TB strategy.

Risk factors for recurrent tuberculosis in England and Wales, 1998-2005.

BACKGROUND: Information on recurrent tuberculosis can provide an indication of the effectiveness of tuberculosis services and identify patients who are most vulnerable. The objective of this study was to estimate the incidence of, and investigate risk factors for, recurrent episodes of tuberculosis in England and Wales. METHODS: Episodes of recurrent tuberculosis were identified among prospectively collected records of tuberculosis cases reported to the Health Protection Agency between 1998 and 2005. An episode of recurrent tuberculosis was defined as a re-notified case in the same patient after at least 12 months from the date of the initial notification. To estimate incidence, follow-up time was calculated for all cases until re-notification or censure. Multivariable Cox proportionate hazard models were used to determine hazard ratios (HR) for recurrence of tuberculosis and investigate the risk associated with clinical, demographic and microbiological factors. RESULTS: Five hundred and eighty-eight recurrent tuberculosis events were identified among 53 214 cases reported between 1998 and 2005, a rate of 4.1 (95% CI 3.8 to 4.5) episodes per 1000 person years of follow-up. Factors independently associated with a greater risk of recurrent tuberculosis were HIV co-infection (HR 1.64, 95% CI 1.13 to 2.38) and belonging to a South Asian ethnic group (HR 1.54, 95% CI 1.23 to 1.93). CONCLUSION: Tuberculosis recurrence is uncommon in England and Wales despite the absence of a universal directly observed treatment policy. The identification of HIV co-infection as a risk factor for recurrent tuberculosis is consistent with findings elsewhere. The higher risk among South Asians, however, requires further investigation.