Fighting force and experience combine to determine contest success in a warlike mammal.

Conflicts between social groups or "intergroup contests" are proposed to play a major role in the evolution of cooperation and social organization in humans and some nonhuman animal societies. In humans, success in warfare and other collective conflicts depends on both fighting group size and the presence and actions of key individuals, such as leaders or talismanic warriors. Understanding the determinants of intergroup contest success in other warlike animals may help to reveal the role of these contests in social evolution. Using 19 y of data on intergroup encounters in a particularly violent social mammal, the banded mongoose (Mungos mungo), we show that two factors, the number of adult males and the age of the oldest male (the "senior" male), have the strongest impacts on the probability of group victory. The advantage conferred by senior males appears to stem from their fighting experience. However, the galvanizing effect of senior males declines as they grow old until, at very advanced ages, senior males become a liability rather than an asset and can be evicted. As in human conflict, strength in numbers and the experience of key individuals combine to determine intergroup contest success in this animal society. We discuss how selection arising from intergroup contests may explain a suite of features of individual life history and social organization, including male eviction, sex-assortative alloparental care, and adult sex ratio.

The production costs of Haemonchus contortus and other nematode parasites in pre-weaned beef calves in New Zealand.

Haemonchus contortus can frequently be found infecting pre-weaned beef calves on sheep and beef farms around the North Island of New Zealand. The purpose of this study was to consider whether the presence of this parasite alone, or as part of a mixed infection, could be impacting growth rates of young animals, on three commercial farms in the North Island of New Zealand. Trials were conducted on commercial sheep and beef farms in each of the Northland, King Country and Gisborne regions, in late summer/autumn (February to April) of 2016 to measure the effect of treatment with narrow and broad spectrum anthelmintics on liveweight gain of spring-born calves pre-weaning. Each farm was chosen based on the presence of Haemonchus and that it was a beef cow/calf system with the cows and calves grazing the same pastures as sheep at some stage. Three sampling visits were made to each farm with the animals being weighed, faecal sampled and treated with one of two anthelmintics (Closantel alone to remove only Haemonchus or a triple combination containing moxidectin, levamisole and oxfendazole to remove all nematodes) or left untreated, on each of the first two visits. There was no significant difference in liveweight gain between any of the treatment groups, hence there was no evidence for an impact of Haemonchus alone, or a mixed nematode infection, on pre-weaned calf growth rates on these farms. It remains unclear whether there may be a justification to consider treatment of calves should they constitute a significant source of pasture larval infestation with H. contortus, in an integrated cattle-sheep system.

Assessment during Intergroup Contests.

Research on how competitors assess (i.e., gather information on) fighting ability and contested resources, as well as how assessment impacts on contest processes and outcomes, has been fundamental to the field of dyadic (one-on-one) contests. Despite recent growth in studies of contests between social-living groups, there is limited understanding of assessment during these intergroup contests. We adapt current knowledge of dyadic contest assessment to the intergroup case, describing what traits of groups, group members, and resources are assessed, and how assessment is manifested in contest processes (e.g., behaviors) and outcomes. This synthesis helps to explain the role of individual heterogeneity in assessment and how groups are shaped by the selective pressure of contests.

Mutual assessment during ritualized fighting in mantis shrimp (Stomatopoda).

Safe and effective conflict resolution is critical for survival and reproduction. Theoretical models describe how animals resolve conflict by assessing their own and/or their opponent's ability (resource holding potential, RHP), yet experimental tests of these models are often inconclusive. Recent reviews have suggested this uncertainty could be alleviated by using multiple approaches to test assessment models. The mantis shrimp Neogonodactylus bredini presents visual displays and ritualistically exchanges high-force strikes during territorial contests. We tested how N. bredini contest dynamics were explained by any of three assessment models-pure self-assessment, cumulative assessment and mutual assessment-using correlations and a novel, network analysis-based sequential behavioural analysis. We staged dyadic contests over burrow access between competitors matched either randomly or based on body size. In both randomly and size-matched contests, the best metric of RHP was body mass. Burrow residency interacted with mass to predict outcome. Correlations between contest costs and RHP rejected pure self-assessment, but could not fully differentiate between cumulative and mutual assessment. The sequential behavioural analysis ruled out cumulative assessment and supported mutual assessment. Our results demonstrate how multiple analyses provide strong inference to tests of assessment models and illuminate how individual behaviours constitute an assessment strategy.

Transformation of hepatitis C antiviral treatment in a national healthcare system following the introduction of direct antiviral agents.

BACKGROUND: Highly effective direct antiviral agents (DAAs) for hepatitis C virus (HCV) were introduced recently. Their utilisation has been limited by high cost and low access to care. AIM: To describe the effect of DAAs on HCV treatment and cure rates in the United States Veterans Affairs (VA) national healthcare system. METHODS: We identified all HCV antiviral treatment regimens initiated from 1 January 1999 to 31 December 2015 (n = 105 369) in the VA national healthcare system, and determined if they resulted in sustained virological response (SVR). RESULTS: HCV antiviral treatment rates were low (1981-6679 treatments/year) in the interferon era (1999-2010). The introduction of simeprevir and sofosbuvir in 2013 and ledipasvir/sofosbuvir and paritaprevir/ombitasvir/ritonavir/dasabuvir in 2014 were followed by increases in annual treatment rates to 9180 in 2014 and 31 028 in 2015. The number of patients achieving SVR was 1313 in 2010, the last year of the interferon era, and increased 5.6-fold to 7377 in 2014 and 21-fold to 28 084 in 2015. The proportion of treated patients who achieved SVR increased from 19.2% in 1999 and 36.0% in 2010 to 90.5% in 2015. Within 2015, monthly treatment rates ranged from 727 in July to 6868 in September correlating with the availability of funds for DAAs. CONCLUSIONS: DAAs resulted in a 21-fold increase in the number of patients achieving HCV cure. Treatment rates in 2015 were limited primarily by the availability of funds. Further increases in funding and cost reductions of DAAs in 2016 suggest that the VA could cure the majority of HCV-infected Veterans in VA care within the next few years.

Assessment of the dimensionality of the Wijma delivery expectancy/experience questionnaire using factor analysis and Rasch analysis.

BACKGROUND: Fear of childbirth has negative consequences for a woman's physical and emotional wellbeing. The most commonly used measurement tool for childbirth fear is the Wijma Delivery Expectancy Questionnaire (WDEQ-A). Although originally conceptualized as unidimensional, subsequent investigations have suggested it is multidimensional. This study aimed to undertake a detailed psychometric assessment of the WDEQ-A; exploring the dimensionality and identifying possible subscales that may have clinical and research utility. METHODS: WDEQ-A was administered to a sample of 1410 Australian women in mid-pregnancy. The dimensionality of WDEQ-A was explored using exploratory (EFA) and confirmatory factor analysis (CFA), and Rasch analysis. RESULTS: EFA identified a four factor solution. CFA failed to support the unidimensional structure of the original WDEQ-A, but confirmed the four factor solution identified by EFA. Rasch analysis was used to refine the four subscales (Negative emotions: five items; Lack of positive emotions: five items; Social isolation: four items; Moment of birth: three items). Each WDEQ-A Revised subscale showed good fit to the Rasch model and adequate internal consistency reliability. The correlation between Negative emotions and Lack of positive emotions was strong, however Moment of birth and Social isolation showed much lower intercorrelations, suggesting they should not be added to create a total score. CONCLUSION: This study supports the findings of other investigations that suggest the WDEQ-A is multidimensional and should not be used in its original form. The WDEQ-A Revised may provide researchers with a more refined, psychometrically sound tool to explore the differential impact of aspects of childbirth fear.

Influence of Social Deprivation on Outcome of Open Arterial Surgery in Tertiary Care: An Observational Study.

BACKGROUND AND OBJECTIVE: Health equity is playing an increasing role in British government health policy. Evidence of social deprivation affecting outcomes in surgery is poor. This study aimed to assess the influence of social deprivation on the outcome of major arterial surgery. MATERIALS AND METHODS: A retrospective cohort study was undertaken in patients undergoing elective or emergency open surgery for abdominal aortic aneurysms or lower limb arterial reconstruction over an eight and a half year period within one institution. Patient deprivation was calculated for each patient with the Index of Multiple Deprivation (IMD) score. This was then entered into multivariate models to determine its effect on mortality and postoperative length of stay after adjustment for confounders. RESULTS: Five hundred and six patients were included in the study. There were 45 deaths (8.9%) and median (IQR) postoperative length of stay was 8 (4-15) days. The median (IQR) IMD score was 46.4 (28.3-64.5). IMD score correlated with ASA grade and was significantly higher in smokers, patients with respiratory disease and those with left ventricular failure. IMD (OR = 1.01; 95% CI = 0.99-1.03; p = .45) did not affected mortality, which was associated with aortic surgery, emergency surgery, and high ASA grade. Postoperative length of stay, which was longer with/after aortic surgery, tissue loss, emergency surgery, high ASA grade, low haemoglobin, and age over 80 years was also independent of deprivation (Spearman's rho = -0.49, p = .28). DISCUSSION: No effect of social deprivation on mortality or length of stay in patients undergoing major arterial surgery was identified.

Bayesian and Markov chain Monte Carlo methods for identifying nonlinear systems in the presence of uncertainty.

In this paper, the authors outline the general principles behind an approach to Bayesian system identification and highlight the benefits of adopting a Bayesian framework when attempting to identify models of nonlinear dynamical systems in the presence of uncertainty. It is then described how, through a summary of some key algorithms, many of the potential difficulties associated with a Bayesian approach can be overcome through the use of Markov chain Monte Carlo (MCMC) methods. The paper concludes with a case study, where an MCMC algorithm is used to facilitate the Bayesian system identification of a nonlinear dynamical system from experimentally observed acceleration time histories.

Building family medicine postgraduate training in Jamaica: overcoming challenges in a resource-limited setting.

This paper recounts the development of family medicine postgraduate training in Jamaica, the challenges faced and lessons learned. A self-administered questionnaire was completed by past trainees exploring the perceived usefulness, strengths and weaknesses of the programme. The results of this study helped guide the strengthening of family medicine training in a resource-limited setting.

Field assessment of synthetic attractants and traps for the Old World screw-worm fly, Chrysomya bezziana.

The performance of newly developed trapping systems for the Old World screw-worm fly, Chrysomya bezziana has been determined in field trials on cattle farms in Malaysia. The efficacy of non-sticky traps and new attractants to trap C. bezziana and non-target flies was compared with the standard sticky trap and Swormlure. The optimal trap was a modified LuciTrap(®) with a new attractant mixture, Bezzilure-2. The LuciTrap/Bezzilure-2 caught on average 3.1 times more C. bezziana than the sticky trap with Swormlure (P<0.05) and provided selectivity for C. bezziana against Chrysomya megacephala and Chrysomya rufifacies with factors of 5.9 and 6.4, respectively. The LuciTrap also discriminates with factors of 90 and 3.6 against Hemipyrellia sp. and sarcophagid flesh flies respectively, compared to the sticky trap. The LuciTrap/Bezzilure-2 system is recommended for screwworm fly surveillance as it is more attractive and selective towards C. bezziana and provides flies of better quality for identification than the sticky trap.

Echocardiographic assessment of pressure volume relations in heart failure and valvular heart disease: using imaging to understand physiology.

Pressure volume (PV) based analysis, using classic hemodynamic principles, has served as a basis for our understanding of cardiac physiology and disease states for decades. However, PV analysis has been restricted to primarily the basic research setting and for preclinical testing and has not be widely applied in part because of the invasive nature of the procedure and the expertise required to obtain adequate data using the conductance catheter. Development of single beat methodologies that rely on echocardiographic measurements of ventricular volume and Doppler and peripheral estimates of ventricular pressure and timing of the cardiac cycle has enabled broader application of PV analysis. This review explores the physiologic background, basic methodology, and recent and potential future applications of noninvasive PV analysis.

Assessing training in sexual dysfunction for genitourinary medicine registrars.

The training programme for specialist registrars in genitourinary medicine (GU) lists sexual dysfunction (SD) as 'beyond essential, core curriculum' despite many GU medicine clinics offering this service. A cross-sectional study was performed of all trainees on the British Association for Sexual Health and HIV mailing list. Data collected included frequency of clinics attended and involvement, any training and interest in future training. A total of 39/76 (51%) responses were received. In total, 20/39 (51%) work in departments with no SD clinic provision, and 12/39 have had some training in SD. In routine GU medicine consultation, 85% trainees are consulted regarding SD at least monthly. In all, 19/39 (49%) work in areas with weekly SD clinics; however, only three trainees were involved. Thirty-four out of 39 (87%) expressed interest in training and 31/39 (79%) respondents would like to see SD training added to the SpR curriculum. Fifty-one percent of juniors work in units without SD provision. Even when SD clinics occur, only three trainees are routinely involved and a large training opportunity is being missed. Despite this, 12/39 trainees have sought out extra training in the form of seminars, courses and meetings. Eighty-five percent wished to have SD as part of the core curriculum as they may ultimately work in an area where these skills are required.

Examining false positives on the Word Memory Test in adults with mild traumatic brain injury.

PRIMARY OBJECTIVE: Many adults with mild traumatic brain injury (MTBI) fail effort tests, indicating poor effort and invalid test results. However, two studies have suggested a high rate of false positives on the Word Memory Test (WMT) in adults with MTBI. This study examines the question of false positives in adults with MTBI who failed the effort subtests of the WMT. RESEARCH DESIGN: A modified and shortened version of the WMT, the Medical Symptom Validity Test (MSVT) was given to adults with MTBI, some of whom failed the WMT. It was also given to samples of schoolchildren in grades two and above, to several hundred children with developmental disabilities and to healthy adults. OUTCOMES AND RESULTS: Failures on the MSVT were far more frequent in adults with MTBI than in second grade children or in children with developmental disabilities. Adults with MTBI who failed the WMT scored much lower on the MSVT effort subtests than children with a mean FSIQ of 63 and much lower than children with impaired memory. CONCLUSIONS: Comparison with developmentally disabled children on the MSVT suggests that the adults with MTBI who failed the WMT were not making an effort to do well on either the WMT or the MSVT. Their results were invalid. False positives on the WMT in adults with mild TBI are very rare.

Provision of forensic medical services to police custody suites in England and Wales: current practice.

INTRODUCTION: Police services within England and Wales are required under the Police and Criminal Evidence Act 1984 to ensure appropriate healthcare to those detained in police custody (forensic medical services). Traditionally doctors have been used by police services to provide an appropriate level of care. Changes within the Act allowed other healthcare professionals (nurses and paramedics and emergency care practitioners) to be included in the provision of such services. The aim of this appears at least in part to have been to reduce the costs of providing such a service. In recent years police services within England and Wales have been outsourced to assorted commercial providers. There are now several different modes of delivery of forensic medical services, which are determined locally by separate police services. AIMS: This study aimed (a) to determine the different modes of delivery of forensic medical services in England and Wales; (b) to determine the healthcare workload caused by Police and Criminal Evidence Act 1984 Codes of Practice; (c) to determine the relative costs of different service models and (d) to determine availability of such information from the police services. METHODS: The study was undertaken in two parts--(a) a telephone survey of all police services, and (b) an application to each police service utilising the Freedom of Information Act 2000. RESULTS: All police services (n=43) in England and Wales were contacted. Of the 41 forces that furnished detailed information; 13/41 had a doctor only service; 20/41 had a doctor/nurse service; 6/41 had a doctor/nurse/paramedic service; 1/41 had a doctor/emergency care practitioner service (who may be nurses or paramedic); 1/41 had a doctor/paramedic service. 23/43 services were outsourced to private commercial providers. Mean cost per patient contact (in 17/43 services which supplied data) was GBP 97.25. The cheapest cost per patient contact was the Metropolitan Police Service - a doctor only service (GBP 56.4), the highest Lincolnshire--a doctor only service (GBP 151.1). Mean cost for a doctor only service was GBP 97.1; for a doctor/nurse service--GBP 91.56 and for a doctor/nurse/paramedic service--GBP 115.76. There was no significant difference in costs per patient contact between a doctor only versus mixed HCP delivery of service. Relative costs and 95% confidence intervals expressed as a percentage show that a doctor only model was on average 3.4% lower than a mixed HCP provision, and that a non-outsourced service was on average 9.9% less than an outsourced service. No outsourced service in this study uses a doctor only model. CONCLUSIONS: The study shows that there was a complete lack of consistency in the recording and availability of information regarding forensic medical services for police services in England and Wales. The information that was obtained suggested that usage of such services varied greatly between police services and that costs of forensic medical services appear to be increased by the use of mixed healthcare professional service delivery and by using external commercial providers.

Quantitative assessment of the degree of villous atrophy in patients with coeliac disease.

BACKGROUND: Endoscopy and biopsy are used to diagnose coeliac disease. There are, however, observer-dependent interpretations of the degree of villous atrophy in biopsies. A pilot study using quantitative image-processing procedures was performed to quantify the degree of villous atrophy in patients with coeliac disease. METHOD: The degree of villous atrophy in duodenal biopsy images was quantified by calculating the ratio of villous edge-to-piecewise arc length (E/P ratio), and this value was compared with the blinded assessment of Marsh score for degree of villous atrophy. RESULTS: Mean E/P ratios for n = 31 biopsy images, 2.76 (SD 0.44) (Marsh IIIa), 1.91 (0.50) (Marsh IIIb) and 1.18 (0.22) (Marsh IIIc), were significantly different (p = 0.006). Based on non-parametric testing, the E/P ratios were inversely correlated with Marsh scores (Spearman coefficient rho = -0.798, Kendall tau = -0.681; p<0.0001). CONCLUSIONS: Biopsy images quantified by image analysis correlated exceedingly well with the histopathological grade of villous atrophy. Since quantified measurements are real-numbered values and lack observer bias, measurement of villous atrophy based on image analysis lends itself to standardisation of histological grading.

Economic burden of a gluten-free diet.

BACKGROUND: Coeliac disease is a common, autoimmune disorder, for which the only treatment is lifelong adherence to a gluten-free diet. This study evaluates the economic burden of adhering to a gluten-free diet. METHODS: A market basket of products identified by name brand, weight or package size for both regular wheat-based products and gluten-free counterparts was developed. The differences in price between purchase venues, both type of store (general grocery store, an upscale grocery store and a health food store and four internet-based grocery sites) and region was also analysed. RESULTS: Availability of gluten-free products varied between the different venues, regular grocery stores carried 36%, while upscale markets carried 41%, and health food stores 94%, compared with 100% availability on the internet. Overall, every gluten-free product was more expensive than their wheat-based counterpart (P

Obstetric skills drills: evaluation of teaching methods.

OBJECTIVE: To determine the most effective method of delivering training to staff on the management of an obstetric emergency. SUBJECTS: The research was conducted in a District General Hospital in the UK, delivering approximately 3500 women per year. Thirty-six staff, comprising of junior and senior medical and midwifery staff were included as research subjects. Each of the staff members were put into one of six multi-professional teams. Effectively, this gave six teams, each comprising of six members. METHOD: Three teaching methods were employed. Lecture based teaching (LBT), simulation based teaching (SBT) or a combination of these two (LAS). Each team of staff were randomly allocated to undertake a full day of training in the management of Post Partum Haemorrhage utilising one of these three teaching methods. Team knowledge and performance were assessed pre-training, post training and at three months later. In addition to this assessment of knowledge and performance, qualitative semi-structured interviews were carried out with 50% of the original cohort one year after the training, to explore anxiety, confidence, communication, knowledge retention, enjoyment and transferable skills. RESULTS: All teams improved in their performance and knowledge. The teams taught using simulation only (SBT) were the only group to demonstrate sustained improvement in clinical management of the case, confidence, communication skills and knowledge. However, the study did not have enough power to reach statistical significance. The SBT group reported transferable skills and less anxiety in subsequent emergencies. SBT and LAS reported improved multidisciplinary communication. Although tiring, the SBT was enjoyed the most. CONCLUSION: Obstetrics is a high risk speciality, in which emergencies are to some extent, inevitable. Training staff to manage these emergencies is a fundamental principal of risk management. Traditional risk management strategies based on incident reporting and event analysis are reactive and not always effective. Simulation based training is an appropriate proactive approach to reducing errors and risk in obstetrics, improving teamwork and communication, whilst giving the student a multiplicity of transferable skills to improve their performance.

Validation of the computerized assessment of response bias in litigating patients with head injuries.

The detection of malingering in neuropsychological assessment requires valid measures of incomplete effort. The Computerized Assessment of Response Bias (CARB) is a digit-recognition procedure designed to detect poor effort during a neuropsychological evaluation. We examined the CARB performance of a consecutive series of litigating patients (N = 119) with a full range of head-injury severity, from trivial to severe. Patients with trivial or mild head injuries performed more poorly than did patients with frank brain injuries. Specifically, patients with moderate to severe traumatic brain injuries obtained higher total scores and demonstrated briefer response latencies than did patients with trivial or mild head injuries.

Effects of injury severity and cognitive exaggeration on olfactory deficits in head injury compensation claims.

The purpose of this study was to examine the relationship between exaggeration and scores on a test of olfactory discrimination in patients being assessed in connection with a claim for financial benefits. Participants were 448 patients referred to a private practice in Edmonton, Alberta, Canada for psychological or neuropsychological assessment, related to evaluation of impairment and disability resulting from a work-related or non-work related accident. All patients were involved in some form of compensation claim at the time of their evaluation. All patients completed two tests designed to detect exaggerated cognitive deficits, the Computerized Assessment of Response Bias (CARB) and the Word Memory Test (WMT) as part of their evaluation. The diagnostic groups included 322 head injury cases, varying from very minor to very severe. Normative data for the smell test were derived from 126 patients with orthopedic injuries who passed both the CARB and the WMT. Patients with more severe traumatic brain injuries were 10-12 times more likely to have olfactory deficits than persons with trivial to mild head injuries. In a subgroup of patients who failed either the CARB or the WMT, there was no relationship between injury severity and total scores on the smell test. Therefore, the dose-response relationship between brain injury severity and olfactory deficits is severely attenuated when patients who are probably exaggerating their cognitive deficits are included in the analyses. Those patients with trivial to mild head injuries who demonstrated adequate effort on both the CARB and the WMT were no more likely to show olfactory deficits than the non-head-injured orthopedic control subjects. Therefore, anosmia following mild traumatic brain injury should not be concluded from self-reports or from tests of smell unless tests of effort have been passed. Effort should also be controlled in group studies of olfaction.

Global water resources: vulnerability from climate change and population growth.

The future adequacy of freshwater resources is difficult to assess, owing to a complex and rapidly changing geography of water supply and use. Numerical experiments combining climate model outputs, water budgets, and socioeconomic information along digitized river networks demonstrate that (i) a large proportion of the world's population is currently experiencing water stress and (ii) rising water demands greatly outweigh greenhouse warming in defining the state of global water systems to 2025. Consideration of direct human impacts on global water supply remains a poorly articulated but potentially important facet of the larger global change question.