Levodopa reverses gait asymmetries related to anhedoniaand magical ideation

Animals and men turn preferentially away from the hemisphere with the more active dopamine (DA) system. Consistent with the idea of a right-hemispheric hyperdopaminergia in schizophrenia, a leftsided turning bias was described for unmedicated psychotic patients. We investigated the modulating role of DA and schizophrenia-like thought on whole-body turns in a controlled double-blind study. The number of veers to either side when walking blindfolded straight ahead (20 meter) was assessed in 40 healthy righthanded men (20 men received levodopa, the remaining participants placebo). Side preferences were analyzed in terms of individuals' positive (Magical Ideation, MI) and negative (Physical Anhedonia, PhysAn) schizotypal features. In the placebo group, increasing MI scores were related to increasing left-sided veering and increasing PhysAn scores were related to increasing right-sided veering. In the levodopa group, this relationship between preferred veering side and type of schizotypy was reversed. The finding in the placebo group suggests an association between MI and a relative right-hemispheric hyperdopaminergia. Unexpectedly, levodopa did not enhance this veering bias, but reversed it, suggesting that psychosis-protective mechanisms exist in the healthy positive "schizotypic” brain. Also unexpectedly, levodopa made "anhedonics” veer like "magics” after placebo, suggesting that DA agonists suppress negative schizotypal symptom

One Hundred Years Later: Stern-Gerlach Experiment and Dimension Witnesses

Inspired by the one-hundredth anniversary of the seminal works of Stern and Gerlach, our contribution is a proposal of how to use their famous experiment in a more contemporary perspective. Our main idea is to re-cast the experiment in the modern language of prepare-and-measure scenarios. By doing so, it is possible to connect geometric and algebraic aspects of the space of states with the physical space. We also discuss possible simulations of the SG experiment as well as some experimental properties of the experiment revealed at the statistical level. Merging a more modern perspective with a paradigmatic experiment, we hope this paper can serve as an entry door for quantum information theory and the foundations of quantum mechanics.Comment: 23 pages, 6 figures. Minor adjustments, according to referee suggestion

Trapping and manipulating neutral atoms with electrostatic fields

We report on experiments with cold thermal $^7$Li atoms confined in combined magnetic and electric potentials. A novel type of three-dimensional trap was formed by modulating a magnetic guide using electrostatic fields. We observed atoms trapped in a string of up to six individual such traps, a controlled transport of an atomic cloud over a distance of 400$\mu$m, and a dynamic splitting of a single trap into a double well potential. Applications for quantum information processing are discussed.Comment: 4 pages, 4 figure

Unit cell of graphene on Ru(0001): a 25 x 25 supercell with 1250 carbon atoms

The structure of a single layer of graphene on Ru(0001) has been studied using surface x-ray diffraction. A surprising superstructure has been determined, whereby 25 x 25 graphene unit cells lie on 23 x 23 unit cells of Ru. Each supercell contains 2 x 2 crystallographically inequivalent subcells caused by corrugation. Strong intensity oscillations in the superstructure rods demonstrate that the Ru substrate is also significantly corrugated down to several monolayers, and that the bonding between graphene and Ru is strong and cannot be caused by van der Waals bonds. Charge transfer from the Ru substrate to the graphene expands and weakens the C-C bonds, which helps accommodate the in-plane tensile stress. The elucidation of this superstructure provides important information in the potential application of graphene as a template for nanocluster arrays.Comment: 9 pages, 3 figures, paper submitted to peer reviewed journa

Perceptual aberrations impair mental own-body transformations

Dysfunctional self and bodily processing have been reported from the schizophrenia spectrum. Here, the authors tested 72 students (40 women) to determine whether performance in a mental own-body transformation task relates to self-rated frequency of spontaneously experienced schizotypal body schema alterations (perceptual aberration). Participants provided speeded left-right decisions concerning the body of a visually depicted human figure (front view vs. back view). For men, reaction times to disembodied perspectives increased with increasing scores on a validated perceptual aberration scale. This finding constitutes behavioral evidence for the clinically postulated association between aberrant bodily experiences during everyday life and aberrant processing in a mental own-body transformation task arguably reflecting mild dysfunction at the temporo-parietal junction

Impact of Dosing Intervals on Activity of Gentamicin and Ticarcillin Against Pseudomonas aeruginosa in Granulocytopenic Mice

The influence of dosing intervals on the activity of gentamicin and ticarcillin against Pseudomonas aeruginosa was studied in vivo. Granulocytopenic mice infected with P. aeruginosa in the thigh muscle were treated with l-hr or 3-hr injections of gentamicin, ticarcillin, or gentamicin-ticarcillin. Plasma pharmacokinetics of the drugs were correlated with antibacterial activity. Gentamicin injected every 1 hr tended to be less active than gentamicin injected at longer intervals. In contrast, ticarcillin given every 1 hr was significantly more efficacious than equivalent total doses injected every 3 hr. The dosing schedule of gentamicin-ticarcillin was again important for ticarcillin but did not appreciably affect the antibacterial activity of gentamicin. Thus, antimicrobial chemotherapy of P. aeruginosa infections in the granulocytopenic host might be improved by administering ticarcillin rather than gentamicin as a constant infusio

Fabrication and functionalization of nanochannels by electron-beam-induced silicon oxide deposition

We report on the fabrication and electrical characterization of functionalized solid-state nanopores in low stress silicon nitride membranes. First, a pore of approximately 50 nm diameter was drilled using a focused ion beam technique, followed by the local deposition of silicon dioxide. A low-energy electron beam induced the decomposition of adsorbed tetraethyl orthosilicate resulting in site-selective functionalization of the nanopore by the formation of highly insulating silicon oxide. The deposition occurs monolayer by monolayer, which allows for control of the final diameter with subnanometer accuracy. Changes in the pore diameter could be monitored in real time by scanning electron microscopy. Recorded ion currents flowing through a single nanopore revealed asymmetry in the ion conduction properties with the sign of the applied potential. The low-frequency excess noise observed at negative voltage originated from stepwise conductance fluctuations of the open pore

What agro-input dealers know, sell and say to smallholder farmers about pesticides: a mystery shopping and KAP analysis in Uganda

BACKGROUND: Pesticides can have negative effects on human and environmental health, especially when not handled as intended. In many countries, agro-input dealers sell pesticides to smallholder farmers and are supposed to provide recommendations on application and handling. This study investigates the role of agro-input dealers in transmitting safety information from chemical manufacturers to smallholder farmers, assesses the safety of their shops, what products they sell, and how agro-input dealers abide by laws and recommendations on best practices for preventing pesticide risk situations. METHODS: Applying a mixed-methods approach, we studied agro-input dealers in Central and Western Uganda. Structured questionnaires were applied to understand agro-input dealers' knowledge, attitude and practices on pesticides (n = 402). Shop layout (n = 392) and sales interaction (n = 236) were assessed through observations. Actual behavior of agro-input dealers when selling pesticides was revealed through mystery shopping with local farmers buying pesticides (n = 94). RESULTS: While 97.0% of agro-input dealers considered advising customers their responsibility, only 26.6% of mystery shoppers received any advice from agro-input dealers when buying pesticides. 53.2% of products purchased were officially recommended. Sales interactions focused mainly on product choice and price. Agro-input dealers showed limited understanding of labels and active ingredients. Moreover, 25.0% of shops were selling repackaged products, while 10.5% sold unmarked or unlabeled products. 90.1% of shops were lacking safety equipment. Pesticides of World Health Organization toxicity class I and II were sold most frequently. Awareness of health effects seemed to be high, although agro-input dealers showed incomplete hygiene practices and were lacking infrastructure. One reason for these findings might be that only 55.7% of agro-input dealers held a certificate of competency on safe handling of pesticides and even fewer (5.7%) were able to provide a government-approved up-to-date license. CONCLUSION: The combination of interviews, mystery shopping and observations proved to be useful, allowing the comparison of stated and actual behavior. While agro-input dealers want to sell pesticides and provide the corresponding risk advice, their customers might receive neither the appropriate product nor sufficient advice on proper handling. In light of the expected increase in pesticide use, affordable, accessible and repeated pesticide training and shop inspections are indispensable