Factors contributing to burnout among perfusionists in the United States

Introduction: As the job climate continues to change, many perfusionists are faced with high employee turnover rates, working longer hours, and increased stress related to more complex surgeries. Understanding the sources of professional burnout and stress may allow the formulation of a strategy to help prevent such negative outcomes. The purpose of this study was to determine the current level of stress and burnout among perfusionists.

Methods: A questionnaire was constructed with the use of SurveyMonkey®. Invitations requesting participation in the survey were distributed by electronic mail to members of PerfList and PerfMail. To assess burnout, components of the well-established Maslach Burnout Inventory (MBI) tool were used.

Results: At p<0.05, job demand variables such as stress level, conflict, call duties, hours worked, and case load were all shown to have a statistically significant relationship to burnout.

Conclusion: The study found that, among the various factors, job demands were the most likely culprit contributing to burnout. Stress level and conflict, in particular, had the strongest association to burnout.

Dietary patterns and risk of breast cancer

Background:

Evidence is emerging that prudent/healthy dietary patterns might be associated with a reduced risk of breast cancer.

Methods:

Using data from the prospective Melbourne Collaborative Cohort Study, we applied principal factor analysis to 124 foods and beverages to identify dietary patterns and estimated their association with breast cancer risk overall and by tumour characteristics using Cox regression.

Results:

During an average of 14.1 years of follow-up of 20 967 women participants, 815 invasive breast cancers were diagnosed. Among the four dietary factors that we identified, only that characterised by high consumption of fruit and salad was associated with a reduced risk, with stronger associations observed for tumours not expressing oestrogen (ER) and progesterone receptors (PR). Compared with women in the lowest quintile of the factor score, the hazard ratio for women in the highest quintile was 0.92 (95% confidence interval (CI)=0.70–1.21; test for trend, P=0.5) for ER-positive or PR-positive tumours and 0.48 (95% CI=0.26–0.86; test for trend, P=0.002) for ER-negative and PR-negative tumours (test for homogeneity, P=0.01).

Conclusion:

Our study provides additional support for the hypothesis that a dietary pattern rich in fruit and salad might protect against invasive breast cancer and that the effect might be stronger for ER- and PR-negative tumours.

Risk factors for cardiovascular disease do not fully explain differences in carotid intima-media thickness between Indigenous and European Australians without diabetes

OBJECTIVE

To investigate whether cardiovascular risk factors can explain the higher carotid intima-media thickness (CIMT) in Indigenous compared with European Australians.

DESIGN

Cross-sectional study in three subgroups.

PATIENTS

Non-diabetic urban European (n = 86), urban Indigenous (n = 69), and remote Indigenous (n = 60) Australians aged 25-64 years.

MEASUREMENTS

CIMT, age, sex, anthropometry, blood pressure, smoking status, fasting glucose and insulin, haemoglobin (Hb)A1c, homocysteine, C-reactive protein (CRP), lipids, urinary albumin and creatinine.

RESULTS

CIMT and levels of risk factors, except fasting glucose and total cholesterol, worsened across the three groups. Log(n) fasting insulin [beta = 0.022, 95% confidence interval (CI) 0-0.0439], age (beta = 0.006, 95% CI 0.004-0.007), gender (female beta = -0.005 vs. male, 95% CI -0.084 to -0.026), mean arterial pressure (MAP) (beta = 0.001, 95% CI 0.001-0.002) and ethnicity/location [urban Indigenous (beta = 0.027, 95% CI -0.010 to 0.064 vs. European); remote Indigenous (beta = 0.083, 95% CI 0.042-0.123 vs. European)] explained 41% of variance in CIMT. Significant interactions were seen for ethnicity/location with age (P = 0.014) and MAP (P = 0.018). Age was consistently associated with CIMT across the three populations, and was associated with larger increments in CIMT for the Indigenous subgroups (beta = 0.007, 95% CI 0.005-0.009 urban; beta = 0.007, 95% CI 0.004-0.010 remote) compared with Europeans (beta = 0.003, 95% CI 0.002-0.006) in models including age, sex and MAP. MAP was only associated with CIMT in the remote Indigenous subgroup.

CONCLUSION

After adjusting for selected risk factors, CIMT in remote Indigenous participants was still higher than in Europeans. The slope of the association between age and CIMT steepened from urban Europeans to remote Indigenous.

Neuronal network models of phase separation between limb CPGs of digging sand crabs

Ordinary differential equations are used to model a peculiar motor behaviour in the anomuran decapod crustacean Emerita analoga. Little is known about the neural circuitry that permits E. analoga to control the phase relationships between movements of the fourth legs and pair of uropods as it digs into sand, so mathematical models might aid in identifying features of the neural structures involved. The geometric arrangement of segmental ganglia controlling the movements of each limb provides an intuitive framework for modelling. Specifically, due to the rhythmic nature of movement, the network controlling the fourth legs and uropods is viewed as three coupled identical oscillators, one dedicated to the control of each fourth leg and one for the pair of uropods, which always move in bilateral synchrony. Systems of Morris-Lecar equations describe the voltage and ion channel dynamics of neurons. Each central pattern generator for a limb is first modelled as a single neuron and then, more realistically as a multi-neuron oscillator. This process results in high-dimensional systems of equations that are difficult to analyse. In either case, reduction to phase equations by averaging yields a two-dimensional system of equations where variables describe only each oscillator's phase along its limit cycle. The behaviour observed in the reduced equations approximates that of the original system. Results suggest that the phase response function in the two dimensional system, together with minimal input from asymmetric bilateral coupling parameters, is sufficient to account for the observed behaviour.

Influence of forage legume species, seeding rate and seed size on competitiveness with annual ryegrass (Lolium rigidum) seedlings

Annual legumes sown as short-term forage crops are an important non-chemical option for the control of herbicide-resistant annual ryegrass (Lolium rigidum L.). The relative ability of 5 annual forage legume species (Trifolium subterraneum L., T. michelianum Savi., T. alexandrinum L., Medicago murex Wild and Vicia benghalensis L.) to suppress annual ryegrass seedlings was examined in a glasshouse study. The experiment investigated the importance of legume species, seed size and seeding rate in influencing the relative competitiveness of the legumes. Balansa clover (T. michelianum) and berseem clover (T. alexandrinum), the smallest seeded of the legume species, were the most effective of the 5 legume species, when compared at equivalent seeding rates, at reducing ryegrass biomass. Legume leaf area and biomass were the 2 factors measured that were most closely associated with depressing ryegrass biomass and were themselves most influenced by legume species and seeding rate. Balansa clover and vetch (V. benghalensis) were the most effective at restricting the amount of light penetrating to 50% of the height of the canopy over a range of seeding rates. The study showed that the competitiveness of forage break crops can be optimised by maximising legume biomass through selecting small-seeded legume species with high relative growth rates and dense canopies and by increasing the seeding rate where seed costs are low.

[The intercontinental schizophrenia outpatient health outcomes study (IC-SOHO): initial 6 month findings of the sample in Latin America]

The IC-SOHO study was designed to supply information on antipsychotic treatments in the real clinical practice by assessment of a large and diverse sample population with schizophrenia. This document describes the findings of the first 6 months of IC-SOHO in Latin America. To date, this is the largest observational study of its type in this region. In this observational and prospective study, those out-patients with schizophrenia, who require a change or initiation of antipsychotic medication are hospitalized. Effectiveness was evaluated using the Clinical Global Impression-Seriousness (CGI-S) grading scale. Tolerability was assessed by questionnaires on adverse events and weight measurements. Herein, the comparisons between olanzapine (monotherapy), risperidone (monotherapy) and conventional antipsychotics (monotherapy and combined therapy) are presented. As a whole, 7,658 patients participated in the ICSOHO; n=2,671 from 11 countries of Latin America that were included in this report. At 6 months, the proportion of patients who responded to olanzapine was significantly greater than those who responded to risperidone or conventional antipsychotics (p<0.001). Patients from the olanzapine group had greater improvements in all the symptom domains, including general, positive, negative, depressive and cognitive symptoms in comparison with risperidone (p<0.05) or conventional antipsychotics (p < 0.001). Extrapyramidal symptoms (EPS) and tardive dyskinesia (TD) decreased from baseline in the groups treated with olanzapine and risperidone, but increased in the conventional group. The adverse events related with the sexual function were more prominent in the conventional group. Weight gain was observed in each treatment group, although the patients from the olanzapine group had greater weight grain followed by those of risperidone and then by those of conventional antipsychotics. Our findings in this population of the Latin American sample emulate the results of other studies in different samples, where it was found that olanzapine was more effective and better tolerated than risperidone or conventional antipsychotics.

Plastic plants and patchy soils

Soil nutrients are distributed in a non-uniform or 'patchy' manner. It is well established that the modular nature of root systems allows them to show both morphological and/or physiological plasticity upon encountering nutrient-rich patches. These plastic responses are widely believed to be foraging mechanisms by the plant to enhance nutrient resource capture. Although morphological plasticity has traditionally been viewed as the more expensive option as it requires new root construction, more recent evidence suggests this may not necessarily be the case. Moreover, plants may be able to recapture most of the initial outlay involved in new root construction, again lowering the overall cost to the plant. Under natural conditions the roots of most plant species have an additional nutrient acquisition mechanism namely mycorrhizal symbiosis. However, the impact of these important symbiotic associations upon the host plant's response to nutrient patches has received relatively little attention. The mycorrhizal fungal symbiont should, in theory, be better able to compete directly with the rest of the microbial community for the nutrients in the patch. This could potentially be important to the host plant, as generally, root proliferation responses are more important for interspecific plant, than plant-microbial, competition.

Socio-demographic inequalities in the diets of mid-aged Australian women

OBJECTIVES

This study reports on the distributions of food and nutrient intakes by socio-demographic factors for a large population sample of mid-aged Australian women participating in the Australian Longitudinal Study on Women's Health.

DESIGN

This cross-sectional population-based study used the Cancer Council of Victoria food frequency questionnaires to derive estimates of food and nutrient intakes.

SETTING

Nationwide community-based survey.

SUBJECTS

A total of 10561 women aged 50-55 y, at the time of the survey in 2001.

RESULTS

Analysis showed favourable patterns of food intake, with frequent consumption of many foods that are promoted as components of a healthy diet (eg, fresh fruit, leafy green and other vegetables, bread, cereals, milk and meat). Intakes of both foods and nutrients varied significantly across socio-demographic groups, with unmarried women, and women in 'labouring' occupations (eg, cleaner, factory worker, kitchenhand) having poorer nutrient intake.

CONCLUSIONS

Although many mid-aged women in this sample had generally healthful diets, women in certain socio-demographic groups (particularly unmarried women and those in labouring occupations) had nutrient intakes of concern. As well as helping to address the dearth of current data on dietary intakes in the Australian population, the results highlight the need for continued targeted public health strategies aimed at improving diet of women from the various socio-economic backgrounds.

N capture by Plantago lanceolata and Brassica napus from organic material: the influence of spatial dispersion, plant competition and an arbuscular mycorrhizal fungus

This study investigated N capture by Plantago lanceolata L. and Brassica napus L. from complex organic material (dual-labelled with 15N/13C) added either as a thin concentrated layer (discrete patch treatment) or dispersed uniformly with the background sand:soil mix in a 10 cm band (dispersed treatment) when grown in monoculture or in interspecific competition and in the presence or absence of a mycorrhizal inoculum (Glomus mosseae). No 13C enrichments from the organic material were detected in the plant tissues, but 15N enrichments were present. Total plant uptake of N from the organic material on a microcosm basis was not affected by the spatial placement of the organic material, but Plantago monocultures captured less N than the species in interspecific competition (i.e. 23% versus 38% of the N originally added). N capture from Brassica monocultures was no different to either Plantago monocultures or both species in mixture. However, N capture from the organic material by both individual Plantago and Brassica plants was reduced when grown with Brassica plants (by 10-fold and by more than half, respectively). N capture from the organic material was directly related to the estimated root length produced in the sections containing the organic material: the individual that produced the greatest root length captured most N. Strikingly, when the organic material was added as a discrete patch the N captured by Brassica, a non-mycorrhizal species, actually increased when the G. mosseae inoculum was present compared to when G. mosseae was absent (i.e. 35% versus 19% of the N originally added).

An arbuscular mycorrhizal fungus accelerates decomposition and acquires nitrogen directly from organic material

Arbuscular mycorrhizal fungi (order Glomales), which form mycorrhizal symbioses with two out of three of all plant species, are believed to be obligate biotrophs that are wholly dependent on the plant partner for their carbon supply. It is thought that they possess no degradative capability and that they are unable to decompose complex organic molecules, the form in which most soil nutrients occur. Earlier suggestions that they could exist saprotrophically were based on observation of hyphal proliferation on organic materials. In contrast, other mycorrhizal types have been shown to acquire nitrogen directly from organic sources. Here we show that the arbuscular mycorrhizal symbiosis can both enhance decomposition of and increase nitrogen capture from complex organic material (grass leaves) in soil. Hyphal growth of the fungal partner was increased in the presence of the organic material, independently of the host plant.

Effect of monensin on milk production of Holstein-Friesian dairy cows

We examined the effects of monensin on feed intake and milk production in Holstein-Friesian cows receiving a total mixed rations in two experiments. In experiment 1, 60 individually fed cows consumed, during wk 7 to 26 of lactation, 1 kg/d of supplement containing either 0, 150,300, or 450 mg of monensin. In experiment 2, 98 group-fed cows also received 1 kg/d of a supplement with either 0 or 300 mg/d of monensin for two consecutive lactations. In lactations 1 and 2, treatment started at wk 8 and 3 wk prior to calving, and continued for 32 wk. In experiment 1, 150, 300, and 450 mg of monensin/d produced a small decrease in feed intake and milk yield responses of 2.8, 2.5 and 1.5 kg/d, respectively. In experiment 2, milk yield responses of 0.8 and 1.1 kg/d were recorded in lactations 1 and 2. Milk fat and milk protein content declined in experiments 1 and 2, lactations 1 and 2 by 0.46, 0.38 and 0.27%, and 0.16, 0.16 and 0.11%, respectively. Yield of milk constituents was unaffected. Efficiency of milk production was increased by 5% in experiment 1. In experiment 2, lactation 2, monensin decreased beta-hydroxybutyrate and acetoacetate but increased blood glucose concentration.

The Anti Cancer Council of Victoria FFQ: relative validity of nutrient intakes compared with weighed food records in young to middle-aged women in a study of iron supplementation

OBJECTIVE

To assess the validity of the Anti Cancer Council of Victoria food frequency questionnaire (ACCVFFQ) relative to seven-day weighed food records (WFRs) in 63 women of child-bearing age.

METHOD

63 women completed WFRs to assess iron intake as part of a study on iron deficiency. These women also completed the ACCVFFQ. Nutrient intakes were computed independently for the WFRs and FFQs. Intakes were compared as group means, by correlation and by quintile classification, adjusting for day-to-day variation in intakes, and for energy intake. Individual differences in results were also examined.

RESULTS

The strongest associations between WFR and FFQ results were energy-adjusted, log-transformed and adjusted for day-to-day variability in intake. Correlation coefficients ranged from 0.28 for vitamin A to 0.78 for carbohydrate. Mean intakes from the WFRs and FFQs were within +/- 20% for 21 of 27 nutrients. Poor agreement between FFQs and WFRs for retinol intake was due to the inclusion of liver in two WFRs, an item which is not included in the FFQ.

CONCLUSION

The ACCVFFQ performs as well as other FFQs for which validation data are available. The relatively poor measurement of retinol is consistent with other data, and with the limited number of foods in which this nutrient is abundant.

IMPLICATIONS

The availability of an optically scannable valid instrument for assessing dietary intake will facilitate epidemiological studies of diet and disease, an area of current research priority.