A multifactorial analysis of acceptance of evolution

Background: Despite decades of education reform efforts, the percent of the general US population accepting biological evolution as the explanation for the diversity of life has remained relatively unchanged over the past 35 years. Previous work has shown the importance of both educational and non-educational (sociodemographic and psychological) factors on acceptance of evolution, but has often looked at such factors in isolation. Our study is among the first attempts to model quantitatively how the unique influences of evolutionary content knowledge, religiosity, epistemological sophistication, and an understanding of the nature of science collectively predict an individual’s acceptance or rejection of evolution. Results: Our study population had a high acceptance of evolution, with an average score of 77.17 (95% C.I. ± 1.483) on the Measure of Acceptance of the Theory of Evolution (MATE) instrument. Our combined general linear model showed that, of the variables in our model, an understanding of the nature of science explained the greatest amount of variation in acceptance of evolution. This was followed in amount of variance explained by a measure of religiosity, openness to experience, religious denomination, number of biology courses previously taken, and knowledge of evolutionary biology terms. Conclusions: Understanding of the nature of science was the single most important factor associated with acceptance of evolution in our study and explained at least four times more variation than measures of evolutionary knowledge. This suggests that educational efforts to impact evolutionary acceptance should focus on increasing an understanding of the nature of science (which may be expected to have additional benefits towards generalized science denial). Additionally, our measure of epistemological sophistication had a unique, significant impact on acceptance of evolution. Both epistemological sophistication and an understanding of the nature of science are factors that might change throughout a liberal arts education, independent of the effect of direct evolutionary instruction

Prevalence, faecal shedding and genetic characterisation of Yersinia spp. in sheep across four states of Australia

Objectives To develop molecular tools for the investigation of the prevalence, species and faecal shedding of Yersinia in sheep. Methods A quantitative PCR (qPCR) targeting the β subunit of the Yersinia spp. RNA polymerase gene was developed and validated. The prevalence of pathogenic Y. enterocolitica was determined by screening for the virulent yst gene. These qPCR assays were used to determine Yersinia spp. prevalence and faecal shedding concentration from 3412 faecal samples collected from approximately 1189 lambs (100–180 lambs/flock) on eight farms across Australia. This was a longitudinal study, with sheep sampled on three occasions (weaning, post-weaning and pre-slaughter). A subset of up to five positive samples from each sampling on each farm (n = 111) was sequenced. Results Yersinia spp. (including both pathogenic and non-pathogenic species) were identified in all flocks, with 60.7% of lambs shedding Yersinia spp. on at least one sampling occasion. Point prevalence ranged from 4% to 91% across farms and sampling occasions. Median Yersinia spp. bacterial concentration was 1.1 × 106, 2.8 × 106 and 5.6 × 105 organisms/g faeces at weaning, post-weaning and pre-slaughter, respectively, across all farms. Pathogenic Y. enterocolitica was identified in all eight flocks sampled, with 14.8% of lambs shedding pathogenic Y. enterocolitica on at least one sampling occasion. Conclusion Yersinia spp. and pathogenic Y. enterocolitica in particular were commonly identified in a sample of Australian sheep flocks using molecular techniques. Further studies into associations between faecal shedding of pathogenic Yersinia spp. and sheep productivity or clinical disease may utilise qPCR in conjunction with other diagnostic tools

Greater intensity and frequency of Cryptosporidium and Giardia oocyst shedding beyond the neonatal period is associated with reductions in growth, carcase weight and dressing efficiency in sheep

Associations between intensity and frequency of Cryptosporidium and Giardia shedding with growth, carcase weight and dressing% were investigated using a longitudinal study of 1182 lambs on eight Australian farms. Live weight was recorded and faecal samples were collected on three sampling occasions; weaning (approximately 12 weeks of age), post-weaning (approximately 19 weeks) and pre-slaughter (approximately 29 weeks). Hot standard carcase weight (HSCW) and dressing% were measured at slaughter. Faecal samples were screened for presence and concentration of Cryptosporidium, Giardia and Haemonchus oocysts using a quantitative PCR. Trichostrongylid eggs were quantified with modified McMaster faecal worm egg count (WEC). Protozoan shedding intensity was categorised as high (above median oocyst concentration in positive sheep), low (below median oocyst concentration in positive sheep) or not detected. Shedding was also categorised for shedding type (no shedding, single Giardia infection, single Cryptosporidium infection, concurrent Giardia and Cryptosporidium infection) and lambs were categorised for frequency of shedding (shedding identified on 0, 1, 2 or 3 occasions). Associations of parasite shedding intensity category, shedding type, shedding frequency, WEC and Haemonchus status (positive or negative) with lamb production were assessed using general linear models (HSCW and dressing%) and linear mixed effects models (live weight). High Cryptosporidium parvum shedding was associated with lower live weight, ranging 2.31–4.52 kg over the 3 sampling occasions. Cryptosporidium parvum shedding was associated with less HSCW in high (3.22 kg less) and low (3.22 kg less) shedding lambs post-weaning, and high (2.21 kg less) and low (2.60 kg less) shedding lambs pre-slaughter as well as lower dressing% (2.7% lower in high shedding lambs post-weaning). Cryptosporidium (all species) shedding pre-slaughter was associated with reduced dressing% in both high (1.25% lower) and low (1.21% lower) shedding lambs. Giardia shedding pre-slaughter was associated with 0.59 kg less HSCW in high shedding lambs. Increased frequency of C. parvum and Giardia shedding in a specific animal (repeated detection) were associated with reduced HSCW and dressing%. Concurrent Giardia and Cryptosporidium shedding pre-slaughter was associated with reduced dressing%. No statistically significant main effects for either WEC (P > 0.05) or Haemonchus status (P > 0.05) were identified for any of the sheep meat productivity measures (live weight, HSCW and dressing%). The findings suggest naturally acquired Cryptosporidium and Giardia infections in grazing sheep are associated with depressed growth, carcase weight and dressing efficiency beyond the neonatal period in sheep representing a range of genetic backgrounds and different sheep production environments

Faecal shedding of pathogenic Yersinia enterocolitica determined by qPCR for yst virulence gene associated with reduced live weight but not diarrhoea in prime lambs

Associations between faecal shedding of pathogenic Yersinia enterocolitica (based on the yst virulence gene) with growth, carcass weight and diarrhoea were investigated using an observational longitudinal study of 1,200 crossbred prime (meat) lambs on eight Australian farms. Live weight, breech faecal soiling score (scale 1-5) and faecal consistency score (FCS; scale 1-5) were recorded, and faecal samples collected from each lamb on three sampling occasions; weaning (≈12 weeks of age), post-weaning (≈19 weeks) and pre-slaughter (≈29 weeks). Hot standard carcass weight was measured at slaughter. Faecal samples were screened for presence and concentration of pathogenic Y. enterocolitica using quantitative PCR. Associations of pathogenic Y. enterocolitica detection and shedding intensity with lamb health and production were assessed using general linear models (carcass weight), linear mixed effects models (live weight, FCS and breech soiling score) and non-parametric tests (FCS and breech soiling score). Prevalence for non-pelleted faeces (FCS ≥ 3.0) and diarrhoea (FCS ≥ 4.0) were compared with the two-tailed z-test, odds ratios and relative risk. Lambs shedding pathogenic Y. enterocolitica were 3.78 kg lighter post-weaning (P < 0.001) and 2.61 kg lighter pre-slaughter (P = 0.035) compared to lambs in which pathogenic Y. enterocolitica was not detected. Higher faecal concentration of pathogenic Y. enterocolitica was associated with lower live weight (P < 0.001). There was no association between pathogenic Y. enterocolitica detection and carcass weight. Overall there was no association between pathogenic Y. enterocolitica detection and FCS or breech soiling score. Only one flock had increased relative risk for non-pelleted faeces associated with pathogenic Y. enterocolitica detection, and one other flock had increased relative risk for diarrhoea associated with pathogenic Y. enterocolitica detection. This is the first report of an association between reduced sheep live weight and pathogenic Y. enterocolitica based on the presence of the yst gene for heat stable enterotoxin determined by qPCR in sheep. Notably, impacts on live weight were observed in the absence of diarrhoea

International Society of Sports Nutrition position stand: beta-alanine

Position statement: The International Society of Sports Nutrition (ISSN) provides an objective and critical review of the mechanisms and use of beta-alanine supplementation. Based on the current available literature, the conclusions of the ISSN are as follows: 1) Four weeks of beta-alanine supplementation (4–6 g daily) significantly augments muscle carnosine concentrations, thereby acting as an intracellular pH buffer; 2) Beta-alanine supplementation currently appears to be safe in healthy populations at recommended doses; 3) The only reported side effect is paraesthesia (tingling), but studies indicate this can be attenuated by using divided lower doses (1.6 g) or using a sustained-release formula; 4) Daily supplementation with 4 to 6 g of beta-alanine for at least 2 to 4 weeks has been shown to improve exercise performance, with more pronounced effects in open end-point tasks/time trials lasting 1 to 4 min in duration; 5) Beta-alanine attenuates neuromuscular fatigue, particularly in older subjects, and preliminary evidence indicates that beta-alanine may improve tactical performance; 6) Combining beta-alanine with other single or multi-ingredient supplements may be advantageous when supplementation of beta-alanine is high enough (4–6 g daily) and long enough (minimum 4 weeks); 7) More research is needed to determine the effects of beta-alanine on strength, endurance performance beyond 25 min in duration, and other health-related benefits associated with carnosine

Cyclotron modeling phase-resolved infrared spectroscopy of polars I: EF Eridani

We present phase-resolved low resolution infrared spectra of the polar EF Eridani obtained over a period of 2 years with SPEX on the IRTF. The spectra, covering the wavelength range 0.8 to 2.4 microns, are dominated by cyclotron emission at all phases. We use a ``Constant Lambda'' prescription to attempt to model the changing cyclotron features seen in the spectra. A single cyclotron emission component with B = 12.6 MG, and a plasma temperature of kT = 5.0 keV, does a reasonable job in matching the features seen in the H and K bands, but fails to completely reproduce the morphology shortward of 1.6 microns. We find that a two component model, where both components have similar properties, but whose contributions differ with viewing geometry, provides an excellent fit to the data. We discuss the implications of our models and compare them with previously published results. In addition, we show that a cyclotron model with similar properties to those used for modeling the infrared spectra, but with a field strength of B = 115 MG, can explain the GALEX observations of EF Eri.Comment: 25 pages, 5 figures, to appear in Ap