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Poster presented at the VSMF symposium held at the Unilever Centre on 2011-01-17The Internet has brought together a group of chemists who are driven by wanting to do things better, but are frustrated with the Closed systems that chemists currently have to work with. they share a belief in the concepts of Open Data, Open Standards and Open Source. And they express this in software, data, algorithms, specifications, tutorials, demonstrations, articles and anything that helps get the message across. [http://www.blueobelisk.org/
Discontinuous collocation methods and gravitational self-force applications
Numerical simulations of extereme mass ratio inspirals, the mostimportant
sources for the LISA detector, face several computational challenges. We
present a new approach to evolving partial differential equations occurring in
black hole perturbation theory and calculations of the self-force acting on
point particles orbiting supermassive black holes. Such equations are
distributionally sourced, and standard numerical methods, such as
finite-difference or spectral methods, face difficulties associated with
approximating discontinuous functions. However, in the self-force problem we
typically have access to full a-priori information about the local structure of
the discontinuity at the particle. Using this information, we show that
high-order accuracy can be recovered by adding to the Lagrange interpolation
formula a linear combination of certain jump amplitudes. We construct
discontinuous spatial and temporal discretizations by operating on the
corrected Lagrange formula. In a method-of-lines framework, this provides a
simple and efficient method of solving time-dependent partial differential
equations, without loss of accuracy near moving singularities or
discontinuities. This method is well-suited for the problem of time-domain
reconstruction of the metric perturbation via the Teukolsky or
Regge-Wheeler-Zerilli formalisms. Parallel implementations on modern CPU and
GPU architectures are discussed.Comment: 29 pages, 5 figure
Optimisation of growth conditions for ovine airway epithelial cell differentiation at an air-liquid interface
Respiratory tract infections are of significant concern in the agriculture industry. There is a requirement for the development of well-characterised in vitro epithelial cell culture models in order to dissect the diverse molecular interactions occurring at the host-pathogen interface in airway epithelia. We have analysed key factors that influence growth and differentiation of ovine tracheal epithelial cells in an air-liquid interface (ALI) culture system. Cellular differentiation was assessed at 21 days post-ALI, a time-point which we have previously shown to be sufficient for differentiation in standard growth conditions. We identified a dose-dependent response to epidermal growth factor (EGF) in terms of both epithelial thickening and ciliation levels. Maximal ciliation levels were observed with 25 ng ml-1 EGF. We identified a strict requirement for retinoic acid (RA) in epithelial differentiation as RA exclusion resulted in the formation of a stratified squamous epithelium, devoid of cilia. The pore-density of the growth substrate also had an influence on differentiation as high pore-density inserts yielded higher levels of ciliation and more uniform cell layers than low pore-density inserts. Differentiation was also improved by culturing the cells in an atmosphere of sub-ambient oxygen concentration. We compared two submerged growth media and observed differences in the rate of proliferation/expansion, barrier formation and also in terminal differentiation. Taken together, these results indicate important differences between the response of ovine tracheal epithelial cells and other previously described airway epithelial models, to a variety of environmental conditions. These data also indicate that the phenotype of ovine tracheal epithelial cells can be tailored in vitro by precise modulation of growth conditions, thereby yielding a customisable, potential infection model
Gesturing in the early universities
Research into the oral and literary traditions of scholastic education usually emphasizes the significance of the word in late medieval pedagogy. This paper suggests that coded hand signals provided early university scholars with an important non-verbal means of communication too. Using illustrations of classroom scenes from early university manuscripts, this paper analyzes the artistic conventions for representing gestures that these images embody. By building up a typology of these gesticulations, it demonstrates that the producers of these images and their audience shared a perception of scholastic education that embraced a sophisticated understanding of the activities associated with university education
Associations between the K232A polymorphism in the diacylglycerol-O-transferase 1 (DGAT1) gene and performance in Irish Holstein-Friesian dairy cattle
peer-reviewedSelection based on genetic polymorphisms requires accurate quantification of the
effect or association of the polymorphisms with all traits of economic importance.
The objective of this study was to estimate, using progeny performance data on 848
Holstein-Friesian bulls, the association between a non-conservative alanine to lysine
amino acid change (K232A) in exon 8 of the diacylglycerol-O-transferase 1 (DGAT1)
gene and milk production and functionality in the Irish Holstein-Friesian population.
The DGAT1 gene encodes the diacylglycerol-O-transferase microsomal enzyme
necessary to catalyze the final step in triglyceride synthesis. Weighted mixed model
methodology, accounting for the additive genetic relationships among animals, was
used to evaluate the association between performance and the K232A polymorphism.
The minor allele frequency (K allele) was 0.32. One copy of the K allele was associated
(P < 0.001) with 77 kg less milk yield, 4.22 kg more fat yield, 0.99 kg less protein
yield, and 1.30 and 0.28 g/kg greater milk fat and protein concentration, respectively;
all traits were based on predicted 305-day production across the first five lactations.
The K232A polymorphism explained 4.8%, 10.3% and 1.0% of the genetic variance in
milk yield, fat yield and protein yield, respectively. There was no association between
the K232A polymorphism and fertility, functional survival, calving performance,
carcass traits, or any conformation trait with the exception of rump width and carcass
conformation. Using the current economic values for the milk production traits
in the Irish total merit index, one copy of the K allele is worth €5.43 in expected
profitability of progeny. Results from this study will be useful in quantifying the
cost-benefit of including the K232A polymorphism in the Irish national breeding programme
Moral Relativism, Religion, Darwinism and Unethical Behavior
The current study investigates the psychological mechanisms involved in unethical behavior, and the role moral relativism plays. It is known that when exposed to religious material, cheating behaviors decrease, and when exposed to moral relativistic material, cheating behavior increases. In light of this, two questions proposed are whether or not religion decreases moral relativism and thus leads to a decrease in cheating behavior, as well as if thoughts of evolution or Darwinism induces thoughts of moral relativism, which in turn leads to an increase in unethical behavior. Ultimately, this study looks to answer whether or not moral relativism is a mediator for unethical behavior. This hypothesis was tested using an online questionnaire. Participants (n =250) were randomly assigned to the religious, Darwinism/evolution or control condition, and then completed questionnaires measuring moral relativism and willingness to engage in unethical behaviors. Results showed that age was correlated with willingness to engage in unethical behavior. There was an indication that the Darwinism/evolution condition was associated with increased unethical behavior, while there was no effect for the religion condition. There was no significant mediation effect of cheating behavior via moral relativism. Future research can be done looking at how thinking about evolutionary theory leads one to engage in unethical behavior.No embargoAcademic Major: Psycholog
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