Observation of Free-Space Single-Atom Matterwave Interference

We observe matterwave interference of a single cesium atom in free fall. The interferometer is an absolute sensor of acceleration and we show that this technique is sensitive to forces at the level of $3.2\times10^{-27}$ N with a spatial resolution at the micron scale. We observe the build up of the interference pattern one atom at a time in an interferometer where the mean path separation extends far beyond the coherence length of the atom. Using the coherence length of the atom wavepacket as a metric, we directly probe the velocity distribution and measure the temperature of a single atom in free fall.Comment: 5 pages, 4 figure

Noch Platz für Nischen? - Bedeutung und Potential alter und gefährdeter Rinderrassen im Ökologischen Landbau

Not only the biodiversity of wild species, but also the diversity in livestock is declining rapidly: Out of 6.300 registered livestock breeds in the world 1.250 are endangered or already extinct. In Germany 16 out of 32 cattle breeds are endangered, while three of the most popular cattle breeds make up 92 % of the more than two million herd-book cows. Due to their adaptation to local conditions on first sight many rare and endangered cattle breeds appear to be well suited for organic farming systems, but the percentage of rare breeds on organic farms is not much higher than on conventional ones. Council Regulation (EC) No 1804/1999 on livestock production in organic farming recommends to encourage biological diversity and to favour the use of breeds which are already adopted to the local conditions. This paper summarises a study on the motivations of organic farmers for keeping rare and endangered cattle breeds, and on which role breeding issues and livestock biodiversity play for organic farming organisations and controlling agencies. The main reasons for keeping rare cattle breeds were good fodder utilization, low susceptibility to diseases, good adaptation to local conditions, but above all a personal relation to a specific breed. Conservation aspects and breed-specific subsidies were of lower importance. Nevertheless, husbandry of rare cattle breeds should be economically viable. Unfortunately most organic farming organisations and controlling agencies hardly touched on breeding and choice-of-breed aspects in their advisory work; they more or less shared the view that the issue was of minor importance for organic farms. The paper concludes with a vision under which conditions rare cattle breeds could be better integrated into organic farming systems and on how organic farming could contribute to the in-situ conservation of livestock genetic resources

Pion scattering in Wilson ChPT

We compute the scattering amplitude for pion scattering in Wilson chiral perturbation theory for two degenerate quark flavors. We consider two different regimes where the quark mass m is of order (i) a\Lambda_QCD^2 and (ii) a^2\Lambda_QCD^3. Analytic expressions for the scattering lengths in all three isospin channels are given. As a result of the O(a^2) terms the I=0 and I=2 scattering lengths do not vanish in the chiral limit. Moreover, additional chiral logarithms proportional to a^2\ln M_{\pi}^2 are present in the one-loop results for regime (ii). These contributions significantly modify the familiar results from continuum chiral perturbation theory.Comment: 20 pages, 4 figures. V3: Comments on finite size effects and the axial vector current added, one more reference. To be published in PR

The Army lessons process: supporting individual and organisational learning in the Australian Army

This paper provides a brief outline of the Army lessons process that is applied when developing and applying lessons across all Army activities. The Army lessons process supports the conduct of operations and informs Army Raise-Train-Sustain functions, through the incorporation of lessons into doctrine, training and capability development. The paper focuses upon four distinct foci. Firstly, we examine the whole of Army responsibility in relation to the transfer of knowledge into lessons. Secondly, we consider the vital roles and responsibilities of knowledge authorities in this transfer. Thirdly, we examine the ways in which observations and insights transform into findings and lessons. Finally, we propose the establishment of the Army Lessons Network as a formal means of knowledge interaction

Fluorescent artificial receptor-based membrane assay (FARMA) for spatiotemporally resolved monitoring of biomembrane permeability

The spatiotemporally resolved monitoring of membrane translocation, e.g., of drugs or toxins, has been a long-standing goal. Herein, we introduce the fluorescent artificial receptor-based membrane assay (FARMA), a facile, label-free method. With FARMA, the permeation of more than hundred organic compounds (drugs, toxins, pesticides, neurotransmitters, peptides, etc.) through vesicular phospholipid bilayer membranes has been monitored in real time (µs-h time scale) and with high sensitivity (nM-µM concentration), affording permeability coefficients across an exceptionally large range from 10$^{-9}$–10$^{-3}$ cm s$^{-1}$. From a fundamental point of view, FARMA constitutes a powerful tool to assess structure-permeability relationships and to test biophysical models for membrane passage. From an applied perspective, FARMA can be extended to high-throughput screening by adaption of the microplate reader format, to spatial monitoring of membrane permeation by microscopy imaging, and to the compartmentalized monitoring of enzymatic activity

Evaluation of Forensic DNA Traces When Propositions of Interest Relate to Activities : Analysis and Discussion of Recurrent Concerns

When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace material, such as “the person of interest is the source of the crime stain.” In particular, when the alternative proposition is “an unknown person is the source of the crime stain,” one is directed to think about the rarity of the profile. However, in the era of DNA profiling technology capable of producing results from small quantities of trace material (i.e., non-visible staining) that is subject to easy and ubiquitous modes of transfer, the issue of source is becoming less central, to the point that it is often not contested. There is now a shift from the question “whose DNA is this?” to the question “how did it get there?” As a consequence, recipients of expert information are now very much in need of assistance with the evaluation of the meaning and probative strength of DNA profiling results when the competing propositions of interest refer to different activities. This need is widely demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative, because of the lack of relevant data and knowledge regarding phenomena and mechanisms of transfer, persistence and background of DNA. Similarly, encouragements to deal with these activity issues, expressed in a recently released European guideline on evaluative reporting (Willis et al., 2015), which highlights the need for rethinking current practice, are sometimes viewed skeptically or are not considered feasible. In this discussion paper, we select and discuss recurrent skeptical views brought to our attention, as well as some of the alternative solutions that have been suggested. We will argue that the way forward is to address now, rather than later, the challenges associated with the evaluation of DNA results (from small quantities of trace material) in light of different activities to prevent them being misrepresented in court