Modeling the emergence of polarity patterns for the intercellular transport of auxin in plants

The hormone auxin is actively transported throughout plants via protein machineries including the dedicated transporter known as PIN. The associated transport is ordered with nearby cells driving auxin flux in similar directions. Here we provide a model of both the auxin transport and of the dynamics of cellular polarisation based on flux sensing. Our main findings are: (i) spontaneous intracellular PIN polarisation arises if PIN recycling dynamics are sufficiently non-linear, (ii) there is no need for an auxin concentration gradient, and (iii) ordered multi-cellular patterns of PIN polarisation are favored by molecular noise.Comment: 17 pages and 9 figures (Main Text), 9 pages and 4 figures (Supplementary Material), revised version with some rearrangement

Job-shop scheduling with limited capacity buffers

In this paper we investigate job-shop problems where limited capacity buffers to store jobs in non-processing periods are present. In such a problem setting, after finishing processing on a machine, a job either directly has to be processed on the following machine or it has to be stored in a prespecified buffer. If the buffer is completely occupied the job may wait on its current machine but blocks this machine for other jobs. Besides a general buffer model, also specific configurations are considered. The aim of this paper is to find a compact representation of solutions for the job-shop problem with buffers. In contrast to the classical job-shop problem, where a solution may be given by the sequences of the jobs on the machines, now also the buffers have to be incorporated in the solution representation. In a first part, two such representations are proposed, one which is achieved by adapting the alternative graph model and a second which is based on the disjunctive graph model. In a second part, it is investigated whether the given solution representation can be simplified for specific buffer configurations. For the general buffer configuration it is shown that an incorporation of the buffers in the solution representation is necessary, whereas for specific buffer configurations possible simplifications are presented

Treatment of bovine sub-clinical mastitis with homeopathic remedies

Considering the positive results of homeopathic therapy of bovine mastitis, the presented study should evaluate the effects of two standardized homeopathic methods in sub-clinical mastitis using a prospective randomized double-blind placebo control study design. A number of 124 dairy cows from 17 herds with increased somatic cell count were selected and randomly associated to 5 treatment groups. Two groups received a peroral therapy with (a) a homeopathic combination over 5 days and (b) a single treatment with a homeopathic nosode (Tuberculinum). To each treatment group a placebo control group was established with the same treatment frequency. A fifth group served as an untreated control. The bacteriological cure rate after 4 and 8 weeks was 28% and the total cure rate additionally regarding a normalized somatic cell count was 14% and 18%, respectively. There was no significant effect by the remedies at all. The cow somatic cell count over three months after treatment showed no significant difference in the five groups. Standardized homeopathic combinations and Tuberculinum nosodes are not able to control sub-clinical mastitis during lactation. If other factors like age and microbial agent are responsible for the success of homeopathy or if more individualized protocols provide better results has to be answered in further investigations

Handling the dry-off problem in organic dairy herds by teat sealing or homeopathy com-pared to therapy omission

Avoiding antibiotics is one of the crucial goals in organic dairy herd health management. Thus, a trial with 102 cows (408 quarters) was conducted to com-pare 2 common medical dry-off practices in organic dairying, internal teat sealant (Orbeseal®, Pfizer) and herd specific homeopathic remedies, with an untreated control. Regarding the sub-clinical mastitis protection rate (IPR), the results show no significant benefit for the two treatment groups in general. The homeopathic group had an advantage in the treatment of cows at drying off showing less than 200k cells/ml. The protection OR of these cows was 5.80 (95%-CI 1.36-29.87) compared to control. Teat sealants showed the best results in protection against environmental infections. Only 13% (n=10/80) of the primarily healthy quarters were infected by environmental Streptococci, Enterococci or Coliforms after calving compared to 21% (15/70; n.s.) after homeopathic treatment and 28% in the control group. This is a 3-fold protection chance (3.04 - 95%-CI 1.2-9.0) compared to control. The results indicate that in herds with good udder health with few environmental infections, a treatment at drying off can be omitted, while sub-clinically in-fected cows could be treated by homeopathics. Only in case of increased environmental infection risk, a strategic teat sealant usage is recommended

Understanding the performance of the low energy neutrino factory: the dependence on baseline distance and stored-muon energy

Motivated by recent hints of large {\theta}13 from the T2K, MINOS and Double Chooz experiments, we study the physics reach of a Low Energy Neutrino Factory (LENF) and its dependence on the chosen baseline distance, L, and stored-muon energy, E_{\mu}, in order to ascertain the configuration of the optimal LENF. In particular, we study the performance of the LENF over a range of baseline distances from 1000 km to 4000 km and stored-muon energies from 4 GeV to 25 GeV, connecting the early studies of the LENF (1300 km, 4.5 GeV) to those of the conventional, high-energy neutrino factory design (4000 km and 7000 km, 25 GeV). Three different magnetized detector options are considered: a Totally-Active Scintillator Detector (TASD) and two models of a liquid-argon detector distinguished by optimistic and conservative performance estimates. In order to compare the sensitivity of each set-up, we compute the full {\delta}-dependent discovery contours for the determination of non-zero {\theta}13, CP-violating values of {\delta} and the mass hierarchy. In the case of large {\theta}13 with sin^2(2*{\theta}13) = (few)*10^{-3}, the LENF provides a strong discovery potential over the majority of the L-E_{\mu} parameter space and is a promising candidate for the future generation of long baseline experiments aimed at discovering CP-violation and the mass hierarchy, and at making a precise determination of the oscillation parameters.Comment: 14 pages, 5 figure

Infinitely-fast diffusion in Single-File Systems

We have used Dynamic Monte Carlo (DMC) methods and analytical techniques to analyze Single-File Systems for which diffusion is infinitely-fast. We have simplified the Master Equation removing the fast reactions and we have introduced a DMC algorithm for infinitely-fast diffusion. The DMC method for fast diffusion give similar results as the standard DMC with high diffusion rates. We have investigated the influence of characteristic parameters, such as pipe length, adsorption, desorption and conversion rate constants on the steady-state properties of Single-File Systems with a reaction, looking at cases when all the sites are reactive and when only some of them are reactive. We find that the effect of fast diffusion on single-file properties of the system is absent even when diffusion is infinitely-fast. Diffusion is not important in these systems. Smaller systems are less reactive and the occupancy profiles for infinitely-long systems show an exponential behavior.Comment: 8 pages, 5 figure

Does family background affect earnings through education? A generalised approach to mediation analysis

We seek to quantify the role of education as a mechanism through which family background affects earnings. To this end, we propose a generalisation of statistical ‘mediation analysis’. In our approach, the treatment and mediator can be multidimensional. This allows us to directly and flexibly account for a range of background characteristics which affect child earnings through the pathway of education and through other mechanisms. The results suggest that educational attainment explains 24%-39% of the overall family background effect on earnings in Australia. The mediating role of education seems to be larger for Australia than for the UK

Engaged Design Scholarship in Contexts

In the 10th year of the Relating Systems Thinking and Design Symposium (RSD), the Systemic Design Association (SDA) board decided to bring a new journal into being for the scholarly community forming in systemic design. As board members, RSD hosts, and editors, we are delighted to announce the availability of a community-driven journal for the field. We hope this will inspire a vigorous epistemic culture and drive additional publications that emerge from an engaged knowledge community. The articles that follow in Volume 1 are the first collection of reviewed contributions from 2022, with five papers reflecting a diversity of studies, themes, and views