Introducing a graph topology for robust cooperation.

Identifying the conditions that support cooperation in spatial evolutionary game theory has been the focus of a large body of work. In this paper, the classical Prisoner's Dilemma is adopted as an interaction model; agents are placed on graphs and their interactions are constrained by a graph topology. A simple strategy update mechanism is used where agents copy the best performing strategy of their neighbourhood (including themselves). In this paper, we begin with a fully cooperative population and explore the robustness of the population to the introduction of defectors. We introduce a graph structure that has the property that the initial fully cooperative population is robust to any one perturbation (a change of any cooperator to a defector). We present a proof of this property and specify the necessary constraints on the graph. Furthermore, given the standard game payoffs, we calculate the smallest graph which possesses this property. We present an approach for increasing the size of the graph and we show empirically that this extended graph is robust to an increasing percentage of perturbations. We define a new class of graphs for the purpose of future work.

A mixed methods epidemiological investigation of preventable deaths among U.S. Army soldiers assigned to a rehabilitative warrior transition unit.

BACKGROUND: The prevalence of medical risk factors for suicide (e.g., mental disorders, severe disability, social disruption) may be higher among WTs compared to traditional Army units. Likewise, the extent to which traditional factors that protect soldiers from developing serious mental disorders (e.g., social support, unit cohesion, leadership) are present among soldiers assigned to the WTU is unclear. OBJECTIVES: An epidemiological consultation (EPICON) was conducted in 2010 to assess potential causes for a perceived high rate of suicides and preventable deaths in U.S. Army Warrior Transition Units (WTUs) and to identify potential improvements to the system of care. METHODS OF STUDY: The EPICON focused on: (1) risk factors for suicide/preventable deaths; (2) chronic pain management; (3) utilization of and access to WTU medical and behavioral health (BH) services; and (4) the impact of the WTU environment on mission focus and warrior disposition. BH history was examined for soldiers who died by suicide or preventable death while assigned to the WTU (index cases) and a representative comparison group of non-index case soldiers. Surveys and focus groups were conducted at four WTUs with Warriors in Transition (WTs) and key support staff. RESULTS: The use of psychotropic and/or CNS depressant medications, prevalence of BH diagnoses and substance use disorders, polypharmacy, alcohol use, and a high cumulative number of stressors were identified as important risk factors for preventable deaths in the WTC. Areas of potential improvement to the system of care included addressing negative perceptions of the WTU environment, lack of social support, barriers to accessing BH services and issues related to coordination of care. CONCLUSIONS: There was no one single risk factor found to be associated with an increased likelihood of preventable deaths within the WTU. The unique design and operation of the WTUs as environments focused on treatment and rehabilitation provide both benefits and challenges to recovery and risk mitigation.

Reliability of energy expenditure prediction equations in the weight management clinic.

BACKGROUND: Few weight management clinics have access to indirect calorimetry with which to measure energy expenditure. Instead, they use energy expenditure prediction equations, which were not designed for use in obesity. We aimed to establish the extent to which such equations overestimate and underestimate resting energy expenditure (REE) in overweight and obese individuals. METHODS: We compared the Schofield, Harris & Benedict, James & Lean and World Health Organisation (WHO) REE prediction equations with the clinical gold standard of indirect calorimetry in 28 males and 168 females, with a mean (SD) age of 28.9 (6.4) years and body mass index (BMI) of 19-67 kg m(-2). RESULTS: The mean REE estimated by indirect calorimetry, and the Schofield, Harris & Benedict, James & Lean and WHO equations were 8.09, 8.30, 8.09, 8.37 and 8.23 MJ day(-1) (1934, 1983, 1933, 2001 and 1966 kcal day(-1)), respectively. Although rising BMI exerted only a small effect on the mean differences between indirect calorimetry and the predicted REE [Schofield: +272 kJ (+65 kcal)/10 units BMI, P = 0.02; Harris & Benedict: +42 kJ (+10 kcal)/10 units BMI, P = 0.69; James & Lean: +217 kJ (+52 kcal) 10 units BMI, P = 0.06 and WHO: +42 kJ (+10 kcal) BMI, P = 0.11], the variance among overweight and obese patients of BMI >25 was substantially higher compared to that among normal weight subjects of BMI <25, on whom the equations were based. The estimated REE by Schofield for an individual of BMI 35 kg m(-2), for example, could lie anywhere from 2.78 MJ (661 kcal) above the indirect calorimetry value to 2.59 MJ (618) kcal below it. CONCLUSIONS: Prediction equations offer a quick assessment of energy needs for hypocaloric diets although, in reality, they run the random risk of excessive restriction or further weight gain.

Renal trauma in the west of Ireland--a regional review.

We herein present a regional review of the management of renal trauma in the west of Ireland. The majority of renal injuries occur as a result of blunt trauma and are amenable to conservative management. We sought to streamline the management of renal trauma in the west of Ireland. With the current restructuring of the Irish Health Service, it is important to acknowledge the role of the urologist in the management of trauma patients.

Primary care utilisation rates in pre-school children.

A key objective of the Lifeways cross generation cohort study is to examine health and healthcare, according to socio-economic indicators, during the first five years of life. GP contact details were available for 1032 children. 772 GPs in 589 practices were approached and data were obtained on 640 children (59% of original cohort). The mean follow-up time was 3.0 years (95% CI 2.5-3.5). 20.5% of children had a medical card. The mean GP consultation rate was 5.5 visits per child per year, 6.6 visits for children with a medical card and 5.1 for those without (95% CI 1.1 to 1.9) p = 0.001. 68 had a diagnosis of asthma; 19.10% with a medical card and 8.9% without (95% CI 3.0-17.5) p = 0.0001. 138 children had ever been admitted to hospital; 26.2% with a medical card and 21.0% without (95% CI -3.3% to 13.6%) p = 0.2. Incremental increases in parental income significantly decreased both the risk of asthma (p = 0.02) or hospital admission (p = 0.008).

CT and MRI 'ring sign' may be due to demyelination: diagnostic pitfall.

We report a case of acute demyelinating encephalomyelitis (ADEM) in which both CT and MRI showed multiple ring-enhancing lesions suggestive of abscesses or brain tumour. This is a relatively rare phenomenon.

Electric field-assisted biosorption.

A bisorption process using electric fields to facilitate contact between a sorbate and non-living biomass is described. The latter is enclosed within a semi-permeable membrane together with an electrode. The counter electrode is placed in the sorbate solution and an established potential across the electrodes facilitates electrokinetic movement of the sorbate to the biosorbant material.

Lipoma of the finger--a case report.

A rare case of a lipoma occurring in the little finger of a 48-year-old woman is described. The presentation and clinical relevance of this and other lipomas occurring in the fingers are discussed.

Pregnancy as an autologous tissue expander for closure of an abdominal-wall defect.

We report the reconstruction of a complex abdominal-wall defect using expanded skin from pregnancy. Wound closure was achieved using a vertical abdominoplasty.

Synovial cyst of the hip joint: an unusual cause of a pulsating groin mass.

Synovial cysts of the hip joint occur most frequently in patients with rheumatoid arthritis (1). Despite the increasing frequency of arthroplasty of rheumatoid hips, case reports documenting synovial cysts remain extremely rare. This case report emphasizes the need for the surgeon to include a synovial cyst in the differential diagnosis of a painless groin mass, particularly in patients with rheumatoid arthritis.

Structural diversity in a family of copper(I) thioether complexes.

Copper(I) complexes of the tridentate thioether ligands [PhB(CH(2)SCH(3))(3)] (abbreviated PhTt), [PhB(CH(2)SPh)(3)] (PhTt(Ph)), [PhB(CH(2)S(t)()Bu)(3)] (PhTt(t)()(Bu)), and [PhB(CH(2)S(p)()Tol)(3)] (PhTt(p)()(Tol)) and bidentate thioether ligands [Ph(2)B(CH(2)SCH(3))(2)] (Ph(2)Bt), [Et(2)B(CH(2)SCH(3))(2)] (Et(2)Bt), and [Ph(2)B(CH(2)SPh)(2)] (Ph(2)Bt(Ph)) have been prepared and characterized. The solution and solid state structures are highly sensitive to the identity of the borato ligand employed. Ligands possessing the smaller (methylthio)methyl donors, [PhTt] and [Ph(2)Bt], yielded tetrameric species, [(PhTt)Cu](4) and [(Ph(2)Bt)Cu](4), containing both terminal and bridging thioether ligation. The ligands containing the larger (arylthio)methyl groups, [PhTt(Ph)] and [PhTt(p)()(Tol)], form monomeric [PhTt(Ar)]Cu(NCCH(3)) in solution and one-dimensional extended structures in the solid state. Each complex type reacted cleanly with acetonitrile, pyridine, or triphenylphosphine generating the corresponding four-coordinate monomer, of which [PhTt(Ph)]Cu(PPh(3)), [PhTt(p)()(Tol)]Cu(PPh(3)), and [Et(2)Bt]Cu(PPh(3))(2) have been structurally characterized.

Is all sexual harassment viewed the same? Mock juror decisions in same- and cross-gender cases.

Given recent court decisions, there is a need to investigate less common forms of sexual harassment, including women harassing men and same-gender harassment. The present study was a 2 (harasser gender) x 2 (target gender) x 2 (participant gender) factorial design in which 408 mock jurors made decisions in a hostile work environment case. Women harassing men were more likely to be found guilty than were men harassing women, and harassers in same-gender cases were more likely to be found guilty and were perceived more negatively than harassers in cross-gender cases. Participant gender differences were found in cross-gender, but not same-gender, conditions. Results suggest that the gender composition of the harasser and target may be an extralegal factor influencing managerial and juror decision making.

Effects of body size on operative, intermediate, and long-term outcomes after coronary artery bypass operation.

BACKGROUND: To investigate the role of body size, if any, on operative and longer term outcomes following coronary artery surgery. METHODS: A total of 3,560 consecutive patients undergoing coronary artery bypass grafting from 1991 to 1997, including 2,401 (67%) males and a mean +/- SD age of 63 +/- 10 years were ranked based on their body mass index (BMI). The association in these patients of preoperative, long-term, and economic data with variations in BMI were studied using regression analyses. Long-term survival was studied using 5-year Kaplan-Meier survival analysis. RESULTS: Operative mortality, myocardial infarction, cerebrovascular accidents, blood transfusions, and length of hospital stay were all increased in the smallest patients (BMI < or = 24 kg/m2). Obesity did not increase adverse operative outcomes except for a greater rate of sternal wound infections occurring with increasing severity of obesity. Direct variable costs were lowest in patients clustered around normal BMI, with cost increasing similarly at low and high extremes. This effect was correlated with similar BMI effects on ventilatory and intensive care requirements. Excluding operative mortality, 5-year survival trends were similarly worse for the smallest (BMI < or = 24) and most severely obese (BMI > 34) patients. Mild obesity (BMI > or = 30 to BMI < 34) did not affect long-term survival. CONCLUSIONS: Among study patients, immediate operative outcomes were adversely affected by small body size, which reflected older age (66 +/- 10 years) and an exaggerated adverse impact of cardiopulmonary bypass. Younger age and smaller effects of cardiopulmonary bypass lead to better operative outcomes in the obese. Long-term outcomes were, however, suboptimal in severely obese patients although that group was the youngest (60 +/- 10 years). In addition to their large body habitus, other factors, including substantial prevalence of diabetes, insulin dependence and hypertension, probably played a significant role in the poor long-term outcome in the severely obese.

Expandable metal stents in the palliation of malignant dysphagia and oesophageal-respiratory fistulae.

The use of self expandable metal stents in the palliation of malignant dysphagia and oesophago-respiratory fistulae has increased in recent years. The aim of this study was to report a comprehensive 4 year audit of a Specialist Unit's experience with the expandable stent. 200 expandable metal stents were deployed for palliation of non operable malignant dysphagia or fistulae. Per-operative, early (<30 days) and late (>30 days) complications specific to the stent were documented. Stents were successfully positioned in all patients. There was no mortality associated with the insertion and no perforation. Dysphagia was palliated initially in 93 per cent of cases. The mean dysphagia score improved significantly from 3.2 to 1.5 (p<0.01). This significant benefit persisted at 3 months and 6 months of follow-up. The commonest complication was stent migration (5.5%) and 23 patients (11%) required a second stent insertion. Oesophago-respiratory fistulae were successfully palliated in all cases. This study demonstrates the effectiveness of self expandable metallic stents in the palliation of non operable malignant dysphagia and oesophago-respiratory fistulae. The minimal risk of significant complications and low incidence of reintervention should establish this approach as first line palliation in these patients.