No evidence for synchronization of the solar cycle by a "clock"

The length of the solar activity cycle fluctuates considerably. The temporal evolution of the corresponding cycle phase, that is, the deviation of the epochs of activity minima or maxima from strict periodicity, provides relevant information concerning the physical mechanism underlying the cyclic magnetic activity. An underlying strictly periodic process (akin to a perfect "clock"), with the observer seeing a superposition of the perfect clock and a small random phase perturbation, leads to long-term phase stability in the observations. Such behavior would be expected if cycles were synchronized by tides caused by orbiting planets or by a hypothetical torsional oscillation in the solar radiative interior. Alternatively, in the absence of such synchronization, phase fluctuations accumulate and a random walk of the phase ensues, which is a typical property of randomly perturbed dynamo models. Based on the sunspot record and the reconstruction of solar cycles from cosmogenic C14, we carried out rigorous statistical tests in order to decipher whether there exists phase synchronization or random walk. Synchronization is rejected at significance levels of between 95% (28 cycles from sunspot data) and beyond 99% (84 cycles reconstructed from C14, while the existence of random walk in the phases is consistent with all data sets. This result strongly supports randomly perturbed dynamo models with little inter-cycle memory.Comment: Astronomy & Astrophysics, in pres

Scanlon\u27s Contractualism and Its Critics

This dissertation examines whether Thomas Scanlon’s contractualism satisfactorily explains its intended domain of morality which he terms “what we owe to each other.” Scanlon proposes that such interpersonal morality is based on justifying one’s actions to others by behaving according to principles that could not be reasonably rejected. This idea accounts for two key functions of a moral theory: explaining how moral judgments are made and why agents generally act according to these judgments. After reviewing the nature of constructivist moral theories to show why I chose to focus on Scanlon’s theory, I assess how effectively it fulfills these two roles. I argue that the concept of justifiability is necessary for making moral judgments because it enables agents to determine which of an action’s attributes are morally relevant and to choose between conflicting principles. However, I also argue that the contractualist procedure is unable to specify principles in certain cases where the aggregation of harms across multiple persons legitimately outweighs an individual’s concerns and in other cases where differences in agents’ experiences and sensibilities lead to conflicting moral judgments and objectionable relativism. Regarding normativity, I argue that justifiability provides sufficient reason for agents to act in accordance with these principles in most, but not all, cases, even if the agents are not motivated by the contractualist goal of finding common principles. In summary, I conclude that contractualism provides an insightful account of morality, but it is one with several significant defects that cannot be remedied

The Effect of Structural Distortions on the Electronic Structure of Carbon Nanotubes

We calculated the effects of structural distortions on the electronic structure of carbon nanotubes. The key modification of the electronic structure brought about by bending a nanotube involves an increased mixing of $\sigma$ and $\pi$-states. This mixing leads to an enhanced density-of-states in the valence band near the Fermi energy region. While in a straight tube the states accessible for electrical conduction are essentially pure C($2p_{\pi}$)-states, they acquire significant C($2sp_{\sigma}$) character upon bending. Bending also leads to a charge polarization of the C-C bonds in the deformed region reminiscent of interface dipole formation. Scattering of conduction electrons at the distorted regions may lead to electron localization at low temperatures.Comment: 11 pages and 4 figures, (figure 4 corrected

Natural variation in flavonol accumulation in Arabidopsis is determined by the flavonol glucosyltransferase BGLU6.

Ishihara H, Tohge T, Viehöver P, Fernie AR, Weisshaar B, Stracke R. Natural variation in flavonol accumulation in Arabidopsis is determined by the flavonol glucosyltransferase BGLU6. Journal of Experimental Botany. 2016;67(5):1505-1517

Protocol for the development of a core domain set for hand eczema trials

Background Clinical hand eczema trials measure a variety of outcome domains to determine the success of interventions. This considerably limits the comparability and overall confidence in the study results, and thereby the strength of recommendations for clinical practice. Objectives The Hand Eczema Core Outcome Set (HECOS) initiative aims to develop a core outcome set (COS) for the standardized evaluation of interventions in future hand eczema trials and reviews. This COS will define the minimum that should be measured and reported in controlled and randomized-controlled trials of therapeutic hand eczema interventions. The objective of this protocol is to specify the methods to develop a core domain set. Methods In Phase 1, a list of candidate domains will be derived from a systematic literature review concerning previously measured outcomes in hand eczema trials, from qualitative patient interviews and from expert interviews. In Phase 2, a consensus study about core domains will be conducted by an online 3-round Delphi survey and a face-to-face meeting, applying predefined consensus criteria. HECOS involves hand eczema and methods experts as well as patients and further stakeholders with an interest in the initiative. Outlook When a set of core domains has been defined, HECOS is going to identify appropriate outcome measurement instruments in a development process that will be detailed in another protocol. The COS will considerably enhance the methodological quality, comparability and usefulness of hand eczema trials for clinical decision-making and the development of new therapeutic options for hand eczema, and also reduce the effort of planning, conducting, and reporting individual hand eczema studies, reviews and meta-analyses