FeederAnt - An autonomous mobile unit feeding outdoor pigs

Small robots and the concept of decentralized animal husbandry make it possible to renew the principles of organic agriculture. The farm animals will be able to use the same type of housing and are placed integrated with the fields. This is expected to achieve a better utilization of nutrients and a better survival rate for useful insects and micro organisms. The small fields are flexible and could fit to the variation in soil structure topography. This type of precision agriculture has the possibility of increasing biodiversity. The paper presents the concept of an autonomic feeding system for outdoor piglets. Initial results are presented using a remote controlled feeding unit (a prototype of the FeederAnt) to feed several pens with piglets. The FeederAnt drives into the grass paddocks twice a day and position itself in a new location for each feeding. This will help to distribute the manure from the animals evenly over the grass paddock to prevent point leaching of nutrients. The FeederAnt replaces many stationary feeding tables and reduce the amount of daily manual feeding routines. Further, it is expected that the problem with vermins will be solved since no feed residues will be left within the pens.

Laser-driven proton acceleration from ultrathin foils with nanoholes

Structured solid targets are widely investigated to increase the energy absorption of high-power laser pulses so as to achieve efficient ion acceleration. Here we report the first experimental study of the maximum energy of proton beams accelerated from sub-micrometric foils perforated with holes of nanometric size. By showing the lack of energy enhancement in comparison to standard flat foils, our results suggest that the high contrast routinely achieved with a double plasma mirror does not prevent damaging of the nanostructures prior to the main interaction. Particle-in-cell simulations support that even a short scale length plasma, formed in the last hundreds of femtoseconds before the peak of an ultrashort laser pulse, fills the holes and hinders enhanced electron heating. Our findings reinforce the need for improved laser contrast, as well as for accurate control and diagnostics of on-target plasma formation

An autonomous robot for feeding outdoor pigs

The objective of this is to develop a rational feeding technique for outdoor pigs and at the same time improve the outdoor system with regard to environmental impact and health. For a rational and competitive free ranch system ensuring high animal welfare and low environmental strain automation is crucial

Gain-of-function Nav1.8 mutations in painful neuropathy

Painful peripheral neuropathy often occurs without apparent underlying cause. Gain-of-function variants of sodium channel Nav1.7 have recently been found in ~30% of cases of idiopathic painful small-fiber neuropathy. Here, we describe mutations in Nav1.8, another sodium channel that is specifically expressed in dorsal root ganglion (DRG) neurons and peripheral nerve axons, in patients with painful neuropathy. Seven Nav1.8 mutations were identified in 9 subjects within a series of 104 patients with painful predominantly small-fiber neuropathy. Three mutations met criteria for potential pathogenicity based on predictive algorithms and were assessed by voltage and current clamp. Functional profiling showed that two of these three Na v1.8 mutations enhance the channel's response to depolarization and produce hyperexcitability in DRG neurons. These observations suggest that mutations of Nav1.8 contribute to painful peripheral neuropathy

Structure Formation, Melting, and the Optical Properties of Gold/DNA Nanocomposites: Effects of Relaxation Time

We present a model for structure formation, melting, and optical properties of gold/DNA nanocomposites. These composites consist of a collection of gold nanoparticles (of radius 50 nm or less) which are bound together by links made up of DNA strands. In our structural model, the nanocomposite forms from a series of Monte Carlo steps, each involving reaction-limited cluster-cluster aggregation (RLCA) followed by dehybridization of the DNA links. These links form with a probability $p_{eff}$ which depends on temperature and particle radius $a$. The final structure depends on the number of monomers (i. e. gold nanoparticles) $N_m$, $T$, and the relaxation time. At low temperature, the model results in an RLCA cluster. But after a long enough relaxation time, the nanocomposite reduces to a compact, non-fractal cluster. We calculate the optical properties of the resulting aggregates using the Discrete Dipole Approximation. Despite the restructuring, the melting transition (as seen in the extinction coefficient at wavelength 520 nm) remains sharp, and the melting temperature $T_M$ increases with increasing $a$ as found in our previous percolation model. However, restructuring increases the corresponding link fraction at melting to a value well above the percolation threshold. Our calculated extinction cross section agrees qualitatively with experiments on gold/DNA composites. It also shows a characteristic ``rebound effect,'' resulting from incomplete relaxation, which has also been seen in some experiments. We discuss briefly how our results relate to a possible sol-gel transition in these aggregates.Comment: 12 pages, 10 figure

Young and Intermediate-age Distance Indicators

Distance measurements beyond geometrical and semi-geometrical methods, rely mainly on standard candles. As the name suggests, these objects have known luminosities by virtue of their intrinsic proprieties and play a major role in our understanding of modern cosmology. The main caveats associated with standard candles are their absolute calibration, contamination of the sample from other sources and systematic uncertainties. The absolute calibration mainly depends on their chemical composition and age. To understand the impact of these effects on the distance scale, it is essential to develop methods based on different sample of standard candles. Here we review the fundamental properties of young and intermediate-age distance indicators such as Cepheids, Mira variables and Red Clump stars and the recent developments in their application as distance indicators.Comment: Review article, 63 pages (28 figures), Accepted for publication in Space Science Reviews (Chapter 3 of a special collection resulting from the May 2016 ISSI-BJ workshop on Astronomical Distance Determination in the Space Age