Quantum Acoustics with Surface Acoustic Waves

It has recently been demonstrated that surface acoustic waves (SAWs) can interact with superconducting qubits at the quantum level. SAW resonators in the GHz frequency range have also been found to have low loss at temperatures compatible with superconducting quantum circuits. These advances open up new possibilities to use the phonon degree of freedom to carry quantum information. In this paper, we give a description of the basic SAW components needed to develop quantum circuits, where propagating or localized SAW-phonons are used both to study basic physics and to manipulate quantum information. Using phonons instead of photons offers new possibilities which make these quantum acoustic circuits very interesting. We discuss general considerations for SAW experiments at the quantum level and describe experiments both with SAW resonators and with interaction between SAWs and a qubit. We also discuss several potential future developments.Comment: 14 pages, 12 figure

Evolutionary Sequence Analysis and Visualization with Wasabi

Wasabi is an open-source, web-based graphical environment for evolutionary sequence analysis and visualization, designed to work with multiple sequence alignments within their phylogenetic context. Its interactive user interface provides convenient access to external data sources and computational tools and is easily extendable with custom tools and pipelines using a plugin system. Wasabi stores intermediate editing and analysis steps as workflow histories and provides direct-access web links to datasets, allowing for reproducible, collaborative research, and easy dissemination of the results. In addition to shared analyses and installation-free usage, the web-based design allows Wasabi to be run as a cross-platform, stand-alone application and makes its integration to other web services straightforward. This chapter gives a detailed description and guidelines for the use of Wasabi's analysis environment. Example use cases will give step-by-step instructions for practical application of the public Wasabi, from quick data visualization to branched analysis pipelines and publishing of results. We end with a brief discussion of advanced usage of Wasabi, including command-line communication, interface extension, offline usage, and integration to local and public web services.Peer reviewe

A direct physical interaction between Nanog and Sox2 regulates embryonic stem cell self-renewal

Embryonic stem (ES) cell self-renewal efficiency is determined by the Nanog protein level. However, the protein partners of Nanog that function to direct self-renewal are unclear. Here, we identify a Nanog interactome of over 130 proteins including transcription factors, chromatin modifying complexes, phosphorylation and ubiquitination enzymes, basal transcriptional machinery members, and RNA processing factors. Sox2 was identified as a robust interacting partner of Nanog. The purified Nanog–Sox2 complex identified a DNA recognition sequence present in multiple overlapping Nanog/Sox2 ChIP-Seq data sets. The Nanog tryptophan repeat region is necessary and sufficient for interaction with Sox2, with tryptophan residues required. In Sox2, tyrosine to alanine mutations within a triple-repeat motif (S X T/S Y) abrogates the Nanog–Sox2 interaction, alters expression of genes associated with the Nanog-Sox2 cognate sequence, and reduces the ability of Sox2 to rescue ES cell differentiation induced by endogenous Sox2 deletion. Substitution of the tyrosines with phenylalanine rescues both the Sox2–Nanog interaction and efficient self-renewal. These results suggest that aromatic stacking of Nanog tryptophans and Sox2 tyrosines mediates an interaction central to ES cell self-renewal

Edge Detection in Landing Budgerigars (Melopsittacus undulatus)

Background: While considerable scientific effort has been devoted to studying how birds navigate over long distances, relatively little is known about how targets are detected, obstacles are avoided and smooth landings are orchestrated. Here we examine how visual features in the environment, such as contrasting edges, determine where a bird will land. Methodology/Principal Findings: Landing in budgerigars (Melopsittacus undulatus) was investigated by training them to fly from a perch to a feeder, and video-filming their landings. The feeder was placed on a grey disc that produced a contrasting edge against a uniformly blue background. We found that the birds tended to land primarily at the edge of the disc and walk to the feeder, even though the feeder was in the middle of the disc. This suggests that the birds were using the visual contrast at the boundary of the disc to target their landings. When the grey level of the disc was varied systematically, whilst keeping the blue background constant, there was one intermediate grey level at which the budgerigar's preference for the disc boundary disappeared. The budgerigars then landed randomly all over the test surface. Even though this disc is (for humans) clearly distinguishable from the blue background, it offers very little contrast against the background, in the red and green regions of the spectrum. Conclusions: We conclude that budgerigars use visual edges to target and guide landings. Calculations of photoreceptor excitation reveal that edge detection in landing budgerigars is performed by a color-blind luminance channel that sums the signals from the red and green photoreceptors, or, alternatively, receives input from the red double-cones. This finding has close parallels to vision in honeybees and primates, where edge detection and motion perception are also largely color-blind

DiAlert: a lifestyle education programme aimed at people with a positive family history of type 2 diabetes and overweight, study protocol of a randomised controlled trial

<p>Abstract</p> <p>Background</p> <p>Family history is a known risk factor for type 2 diabetes (T2DM), and more so in the presence of overweight. This study aims to develop and evaluate the effectiveness of a new lifestyle education programme 'DiAlert' targeted at 1st degree relatives of people with T2DM and overweight. In view of the high risk for diabetes and cardiovascular disease in immigrants from Turkish origin living in Western Europe, a culturally appropriate Turkish version of DiAlert will be developed and tested.</p> <p>Methods/design</p> <p>In this RCT, 268 (134 Dutch and 134 Turkish) overweight 1st degree relatives of patients with T2DM will be allocated to either the intervention or control group (leaflet). The intervention DiAlert aims to promote intrinsic motivation to change lifestyle, and sustain achieved behaviour changes during follow-up. Primary outcome is weight loss. Secondary outcomes include biological, behavioural and psychological indices, along with process indicators. Measurements will take place at baseline and after 3 and 9 months. Changes in outcomes are tested between intervention and control group at 3 months; effects over time are tested within and between both ethnic groups at 3 and 9 months.</p> <p>Discussion</p> <p>The DiAlert intervention is expected to be more effective than the control condition in achieving significant weight loss at 3 months, in both Dutch and Turkish Dutch participants.</p> <p>Trial registration</p> <p>Netherlands National Trial Register (NTR): <a href="http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2036">NTR2036</a></p

Exploration of the rotational power consumption of a rigid flapping wing

Accepted versio

Bacteriological and physico-chemical assessment of wastewater in different region of Tunisia: impact on human health

<p>Abstract</p> <p>Background</p> <p>In many parts of the world, health problems and diseases have often been caused by discharging untreated or inadequately treated wastewater. In this study, we aimed to control physico-chemical parameters in wastewater samples. Also, microbiological analyses were done to reveal <it>Salmonella </it>strains and each <it>Escherichia coli </it>(<it>E.coli</it>) pathotype.</p> <p>Findings</p> <p>Sixty wastewater samples were collected from fifteen different regions of Tunisia. All physico-chemical parameters (pH, residual free chlorine, total suspended solids, biological oxygen demand, and chemical oxygen demand) were evaluated.</p> <p>For microbiological analyses, samples were filtered to concentrate bacteria. DNA was extracted by boiling and subjected to polymerase chain reaction (PCR) using different pairs of primers.</p> <p>The mean pH values recorded for the sampling point were above the WHO pH tolerance limit. The total suspended solids (TSS) concentrations varied between 240 mg/L and 733 mg/L in entrance points and between 13 mg/L and 76 mg/L in exit points. In entrance points, the studied wastewater has an average COD concentration that varied between 795 mg/mL to 1420 mg/mL. Whereas, BOD concentration of the wastewater ranged between 270 mg/L to 610 mg/L. In exit points, COD concentration varied between 59 mg/L and 141 mg/L, whereas BOD concentration ranged from 15 mg/L to 87 mg/L.</p> <p>The bacteriological control of wastewaters showed that, in entrance points, <it>Escherichia coli </it>(<it>E.coli</it>) was detected at the rate of 76.6%. Three <it>E.coli </it>pathotypes were found: ETEC (53.3%), EAEC (16.6%) and EIEC (6.6%).</p> <p>Concerning the ETEC isolated strains, 8 of 16 (50%) have only the heat-labile toxin gene, 5 of 16 (31.2%) present only the heat-stable toxin gene and 3 of 16 (18.7%) of strains possess both heat-labile toxin gene and heat-stable toxin gene. In exist point, the same pathotypes were found but all detected ETEC strains present only the "est" gene.</p> <p>Concerning <it>Salmonella </it>isolated strains; percentages of 66.6% and 20% were found in entrance and exit points respectively.</p> <p>Conclusions</p> <p>Wastewaters contain a large amount of pathogenic bacteria that present a real impact on human health. Assessment wastewater treatment stations have to consider in account enterobacterial pathogens as potential pathogens that should be correctly controlled.</p