Maximally entangled mixed states: Creation and concentration

Using correlated photons from parametric downconversion, we extend the boundaries of experimentally accessible two-qubit Hilbert space. Specifically, we have created and characterized maximally entangled mixed states (MEMS) that lie above the Werner boundary in the linear entropy-tangle plane. In addition, we demonstrate that such states can be efficiently concentrated, simultaneously increasing both the purity and the degree of entanglement. We investigate a previously unsuspected sensitivity imbalance in common state measures, i.e., the tangle, linear entropy, and fidelity.Comment: 4 pages, 3 figures, 1 table; accepted versio

A homoleptic phosphine adduct of Tl(I)

A homoleptic phosphine adduct of thallium(I) supported by a tris(phosphino)borate ligand has been isolated and structurally characterized

Converged Velocity Field for Rotors by a Blended Potential Flow Method

Potential-flow solutions for rotor induced flow by the He method give good convergence on the disk but can provide only a crude approximation off of the disk. The Morillo-Duffy formulation can give all three components off the disk, but the results converge poorly on the disk. Furthermore, Morillo-Duffy solutions converge very slowly for the velocity downstream in the limit as wake skew angle approaches 90º edgewise flow). In this work, new variables––called the Nowak-He variables––are introduced that provide both the He velocity and the Morillo-Duffy velocity from a single set of states. In addition, an approximate downstream velocity field is obtained from the adjoint theorem thatgives the exact downstream velocity as skew angle approaches 90º. The blending of these three velocity fields is shown to give robust and accurate convergence to the potential-flow equations at all flight conditions

Evidences of Positive and Negative Transfer Effects Between Highly Similar Perceptual-Motor Tasks

One hundred twenty male undergraduates, each assigned to one of two groups, performed highly similar perceptual-motor tasks varying in difficulty. The tasks were provided by the Multipoint Two-Hand Coordinator. On Day 2, one-half of the Ss in each group changed tasks while one-half continued on the same task. Evidences of positive and negative transfer effects were found with greater positive transfer from the easier to the more difficult task than in the reverse direction. A striking feature of the study was the persistence of negative transfer effects

Noise power spectral density of the Sundstrand QA-2000 accelerometer

There are no good data on low frequency (less than 0.1 Hz) power spectral density (PSD) for the Q-Flex accelerometer. However, some preliminary stability measurements were made over periods of 12 to 24 hours and demonstrated stability less than 0.5 micro-g over greater than 12 hours. The test data appear to contain significant contributions from temperature variations at that level, so the true sensor contribution may be less than that. If what was seen could be construed as a true random process, it would correspond to about 0.1 micro-g rms over a bandwidth from 10(exp -5) Hz to about 1 Hz. Other studies of low frequency PSD in flexure accelerometers have indicated that material aging effects tend to approximate a first order Markhov process. If we combine such a model with the spectrum obtained at higher frequencies, it suggests the spectrum shown here as a conservative estimate of Q-Flex noise performance

Bubble collapse near porous plates

A gas or vapour bubble near a solid boundary collapses towards the boundary due to the asymmetry induced by the nearby boundary. High surface pressure and shear stress from this collapse can damage, or clean, the surface. A porous boundary, such as a filter, would act similarly to a solid boundary but with reduced asymmetry and thus reduced effect. Prior research has measured the cleaning effect of bubbles on filters using ultrasonic cleaning, but it is not known how the bubble dynamics are fundamentally affected by the porosity of the surface. We address this question experimentally by investigating how the standoff distance, porosity, pore size, and pore shape affect two collapse properties: bubble displacement and bubble rebound size. We show that these properties depend primarily on the standoff distance and porosity of the boundary and extend a previously developed numerical model that approximates this behaviour. Using the numerical model in combination with experimental data, we show that bubble displacement and bubble rebound size each collapse onto respective single curves

Levo-Tetrahydropalmatine Attenuates Cocaine Self-Administration under a Progressive-Ratio Schedule and Cocaine Discrimination in Rats

Levo-tetrahydropalmatine (l-THP) is an alkaloid found in many traditional Chinese herbal preparations and has a unique pharmacological profile that includes dopamine receptor antagonism. Previously we demonstrated that l-THP attenuates fixed-ratio (FR) cocaine self-administration (SA) and cocaine-induced reinstatement in rats at doses that do not alter food-reinforced responding. This study examined the effects of l-THP on cocaine and food SA under progressive-ratio (PR) schedules of reinforcement and the discriminative stimulus effects of cocaine. In adult male Sprague–Dawley rats self-administering cocaine (0.5 or 1.0 mg/kg/inf), l-THP significantly reduced breaking points at the 1.875, 3.75 and 7.5 mg/kg doses. l-THP also reduced the breaking point and response rate for PR SA of sucrose-sweetened food pellets, although the decrease was significant only at the 7.5 mg/kg l-THP dose. In rats trained to discriminate cocaine (10 mg/kg, ip) from saline, l-THP (1.875, 3.75 and 7.5 mg/kg) produced a rightward shift in the dose–response curve for cocaine generalization. During generalization testing, l-THP reduced response rate, but only at the 7.5 mg/kg dose. l-THP also prevented substitution of the dopamine D2/D3 receptor agonist, (±) 7-OH-DPAT, for cocaine suggesting a potential role for antagonism of D2 and/or D3 receptors in the effects of l-THP. These data further demonstrate that l-THP attenuates the reinforcing and subjective effects of cocaine at doses that do not produce marked motor effects and provide additional evidence that l-THP may have utility for the management of cocaine addiction

Linguistic alignment and theory of mind impairments in schizophrenia patients' dialogic interactions

BACKGROUND: Impairments of contextual processing and theory of mind (ToM) have both been offered as accounts of the deviant language characterising formal thought disorder (FTD) in schizophrenia. This study investigated these processes in patients' dialogue. We predicted that FTD patients would show a decrement in linguistic alignment, associated with impaired ToM in dialogue. METHODS: Speech samples were elicited via participation in an interactive computer-based task and a semi-structured interview to assess contextual processing abilities and ToM skills in dialogue, respectively, and from an interactive card-sorting task to measure syntactic alignment. Degree of alignment in dialogue and the syntactic task, and evidence of ToM in (i) dialogue and (ii) a traditional ToM task were compared across schizophrenia patients with FTD (n = 21), non-FTD patients (n = 22) and healthy controls (n = 21). RESULTS: FTD patients showed less alignment than the other two groups in dialogue, and than healthy controls on the syntactic task. FTD patients showed poorer performance on the ToM task than the other two groups, but only compared to the healthy controls in dialogue. The FTD group's degree of alignment in dialogue was correlated with ToM performance in dialogue but not with the traditional ToM task or with syntactic alignment. CONCLUSIONS: In dialogue, FTD patients demonstrate an impairment in employing available contextual information to facilitate their own subsequent production, which is associated with a ToM deficit. These findings indicate that a contextual processing deficit impacts on exploiting representations via the production system impoverishing the ability to make predictions about upcoming utterances in dialogue

Automated analysis of atrial late gadolinium enhancement imaging that correlates with endocardial voltage and clinical outcomes: A 2-center study

This work was supported by the British Heart Foundation PG/10/37/28347, RG/10/11/28457, NIHR Biomedical Research Centre funding, and the ElectroCardioMaths Programme of the Imperial BHF Centre of Research Excellence

Variation in habitat soundscape characteristics influences settlement of a reef-building coral

© The Author(s), 2016. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in PeerJ 4 (2016): e2557, doi:10.7717/peerj.2557.Coral populations, and the productive reef ecosystems they support, rely on successful recruitment of reef-building species, beginning with settlement of dispersing larvae into habitat favourable to survival. Many substrate cues have been identified as contributors to coral larval habitat selection; however, the potential for ambient acoustic cues to influence coral settlement responses is unknown. Using in situ settlement chambers that excluded other habitat cues, larval settlement of a dominant Caribbean reef-building coral, Orbicella faveolata, was compared in response to three local soundscapes, with differing acoustic and habitat properties. Differences between reef sites in the number of larvae settled in chambers isolating acoustic cues corresponded to differences in sound levels and reef characteristics, with sounds at the loudest reef generating significantly higher settlement during trials compared to the quietest site (a 29.5 % increase). These results suggest that soundscapes could be an important influence on coral settlement patterns and that acoustic cues associated with reef habitat may be related to larval settlement. This study reports an effect of soundscape variation on larval settlement for a key coral species, and adds to the growing evidence that soundscapes affect marine ecosystems by influencing early life history processes of foundational species.Funding for this project was provided by a PADI Foundation Grant (#11304) to AL and US. National Science Foundation Grant OCE-1234688 to DE and DB. Financial support to AL during manuscript preparation was also provided by the Woods Hole Oceanographic Institution’s Ocean Life and Coastal Ocean Institutes