3,564 research outputs found
Modelling of selection and mating decisions in tree breeding programs
Hardwood trees from the temperate forests of southern Australia are an important source of timber for high quality paper. Two species in particular, Eucalyptus globulus and Eucalyptus nitens are well suited to this purpose and are now widely grown in commercial plantations. These plantations have been established by professional tree breeders using seedlings derived originally from broadly based collection of seed in natural forests. To increase productivity it is desirable to select trees that grow quickly and give high yields of top quality timber. Nevertheless it is important to maintain genetic diversity in the breeding population and thereby retain a robust capacity to adapt to changing environmental factors. In this article we formulate a number of related mathematical models for the selection and mating processes and discuss the consequences of these models. We recommend a relatively simple scheme which can be implemented on an IBM compatible PC using standard algorithms
Engaging our school teachers: An augmented reality (AR) approach to continuous professional development
Currently, trainee teachers in the UK learn about behaviour management strategies from a theoretical perspective at university, through discussions with their school mentors, and by trial and error at their school placement. Existing literature mainly focuses on these issues from the ‘adult’ viewpoint, not the voice of the child. This paper reports on work-in-progress developing a range of Augmented Reality (AR) resources, drawing upon co-design research workshops with children from a Year 6 class (aged 10) in a UK Primary School. Our research informs approaches to classroom management by encouraging reflection and analysis of ‘critical incidents’ identified by the pupils, and explored by trainee teachers in workshops through the medium of AR, giving a reality previously uncaptured in more traditional approaches. Our final resources will be a set of Open Education Resources (OER), offered to the wider community for reuse/ repurposing for educational settings through a Creative Commons (cc) licence
Best causal mathematical models for a nonlinear system
©2005 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.We provide new causal mathematical models of a nonlinear system S which are specifications of a nonlinear operator P/sub p/ of degree p=1,2,.... The operator P/sub p/ is determined from a special orthogonalization procedure and minimization of the mean squared difference between outputs of S and P/sub p/. As a result, these models have smallest possible associated errors in the class of such operators P/sub p/. The causality condition is implemented through the use of specific matrices called lower trapezoidal. The associated computational work is reduced by the use of the orthogonalization procedure. We provide a strict justification of the proposed approach including theorems on an explicit representatoin of the models' parameters, and theorems on the associated error representation. The possible extensions of the proposed approach and its potential applications are outlined.Anatoli Torokhti, Phil Howlett, and Charles Pearc
A nod in the wrong direction : Does nonverbal feedback affect eyewitness confidence in interviews?
Eyewitnesses can be influenced by an interviewer's behaviour and report information with inflated confidence as a result. Previous research has shown that positive feedback administered verbally can affect the confidence attributed to testimony, but the effect of non-verbal influence in interviews has been given little attention. This study investigated whether positive or negative non-verbal feedback could affect the confidence witnesses attribute to their responses. Participants witnessed staged CCTV footage of a crime scene and answered 20 questions in a structured interview, during which they were given either positive feedback (a head nod), negative feedback (a head shake) or no feedback. Those presented with positive non-verbal feedback reported inflated confidence compared with those presented with negative non-verbal feedback regardless of accuracy, and this effect was most apparent when participants reported awareness of the feedback. These results provide further insight into the effects of interviewer behaviour in investigative interviewsPeer reviewedFinal Accepted Versio
A philosophy for the modelling of realistic nonlinear systems
First published in Proceedings of the American Mathematical Society in volume 132, number 2, by the American Mathematical Society Copyright © 2003 American Mathematical SocietyA nonlinear dynamical system is modelled as a nonlinear mapping from a set of input signals into a corresponding set of output signals. Each signal is specified by a set of real number parameters, but such sets may be uncountably infinite. For numerical simulation of the system each signal must be represented by a finite parameter set and the mapping must be defined by a finite arithmetical process. Nevertheless the numerical simulation should be a good approximation to the mathematical model. We discuss the representation of realistic dynamical systems and establish a stable approximation theorem for numerical simulation of such systems.Phil Howlett, Anatoli Torokhti, Charles Pearc
COBRA: a new European research project for organic plant breeding
Development of organic plant breeding and seed production will have a valuable impact on organic plant production. Breeding of plant material adapted for organic agriculture is crucial in order to cope with stresses such as climate change, weeds and seed borne diseases. Conventional varieties may not meet the specific needs of organic agriculture. The use of plant material adapted to conditions of organic agriculture will have a positive effect on the productivity and sustainability of organic crop production
In silico interaction analysis of cannabinoid receptor interacting protein 1b (CRIP1b) � CB1 cannabinoid receptor
Cannabinoid Receptor Interacting Protein isoform 1b (CRIP1b) is known to interact with the CB1 receptor. Alternative splicing of the CNRIP1 gene produces CRIP1a and CRIP1b with a difference in the third exon only. Exons 1 and 2 encode for a functional domain in both proteins. CRIP1a is involved in regulating CB1 receptor internalization, but the function of CRIP1b is not very well characterized. Since there are significant identities in functional domains of these proteins, CRIP1b is a potential target for drug discovery. We report here predicted structure of CRIP1b followed by its interaction analysis with CB1 receptor by in-silico methods A number of complementary computational techniques, including, homology modeling, ab-initio and protein threading, were applied to generate three-dimensional molecular models for CRIP1b. The computed model of CRIP1b was refined, followed by docking with C terminus of CB1 receptor to generate a model for the CRIP1b- CB1 receptor interaction. The structure of CRIP1b obtained by homology modelling using RHOGDI-2 as template is a sandwich fold structure having beta sheets connected by loops, similar to predicted CRIP1a structure. The best scoring refined model of CRIP1b in complex with the CB1 receptor C terminus peptide showed favourable polar interactions. The overall binding pocket of CRIP1b was found to be overlapping to that of CRIP1a. The Arg82 and Cys126 of CRIP1b are involved in the majority of hydrogen bond interactions with the CB1 receptor and are possible key residues required for interactions between the CB1 receptor and CRIP1b. © 2017 Elsevier Inc
Measuring the growth rate of structure with Type IA Supernovae from LSST
We investigate measuring the peculiar motions of galaxies up to using
Type Ia supernovae (SNe Ia) from LSST, and predict the subsequent constraints
on the growth rate of structure. We consider two cases. Our first is based on
measurements of the volumetric SNe Ia rate and assumes we can obtain
spectroscopic redshifts and light curves for varying fractions of objects that
are detected pre-peak luminosity by LSST (some of which may be obtained by LSST
itself and others which would require additional follow-up). We find that these
measurements could produce growth rate constraints at that
significantly outperform those using Redshift Space Distortions (RSD) with DESI
or 4MOST, even though there are fewer objects. For our second
case, we use semi-analytic simulations and a prescription for the SNe Ia rate
as a function of stellar mass and star formation rate to predict the number of
LSST SNe IA whose host redshifts may already have been obtained with the
Taipan+WALLABY surveys, or with a future multi-object spectroscopic survey. We
find and SN Ia with host redshifts for these cases
respectively. Whilst this is only a fraction of the total LSST-detected SNe Ia,
they could be used to significantly augment and improve the growth rate
constraints compared to only RSD. Ultimately, we find that combining LSST SNe
Ia with large numbers of galaxy redshifts will provide the most powerful probe
of large scale gravity in the regime over the coming decades.Comment: 12 pages, 1 table, 5 figures. Accepted for publication in ApJ. The
Fisher matrix forecast code used in this paper can be found at:
https://github.com/CullanHowlett/PV_fisher. Updated to fix error in Eq. 1
(thanks to Eric Linder for pointing this out
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