Gate Defined Quantum Confinement in Suspended Bilayer Graphene

Quantum confined devices that manipulate single electrons in graphene are emerging as attractive candidates for nanoelectronics applications. Previous experiments have employed etched graphene nanostructures, but edge and substrate disorder severely limit device functionality. Here we present a technique that builds quantum confined structures in suspended bilayer graphene with tunnel barriers defined by external electric fields that break layer inversion symmetry, thereby eliminating both edge and substrate disorder. We report clean quantum dot formation in two regimes: at zero magnetic field B using the single particle energy gap induced by a perpendicular electric field and at B > 0 using the quantum Hall ferromagnet {\nu} = 0 gap for confinement. Coulomb blockade oscillations exhibit periodicity consistent with electrostatic simulations based on local top gate geometry, a direct demonstration of local control over the band structure of graphene. This technology integrates single electron transport with high device quality and access to vibrational modes, enabling broad applications from electromechanical sensors to quantum bits.Comment: 22 pages, 9 figures, includes supplementary informatio

Optimizing genetics online resources for diverse readers.

PurposeClear and accurate genetic information should be available to health-care consumers at an individualized level of comprehension. The objective of this study is to evaluate the complexity of common online resources and to simplify text content using automated text processing tools.MethodsWe extracted all text from Genetics Home Reference and MedlinePlus in bulk and analyzed content using natural language processing. We applied custom tools to improve the readability and compared readability before and after text optimization.ResultsCommonly used educational materials were more complex than the recommended reading level for the general public. Genetic health information entries from Genetics Home Reference (n = 1279) were written at a median 13.0 grade level. MedlinePlus entries, which are not exclusively genetic (n = 1030), had a median grade level of 7.7. When we optimized text for the 59 actionable conditions by prioritizing medical details using a standard structure, the average reading grade level improved.ConclusionFactors that increase complexity are long sentences and difficult words. Future strategies to reduce complexity include prioritizing relevant details and using more illustrations. Simplifying and providing standardized online health resources would benefit diverse consumers and promote inclusivity

Human Communication Systems Evolve by Cultural Selection

Human communication systems, such as language, evolve culturally; their components undergo reproduction and variation. However, a role for selection in cultural evolutionary dynamics is less clear. Often neutral evolution (also known as 'drift') models, are used to explain the evolution of human communication systems, and cultural evolution more generally. Under this account, cultural change is unbiased: for instance, vocabulary, baby names and pottery designs have been found to spread through random copying. While drift is the null hypothesis for models of cultural evolution it does not always adequately explain empirical results. Alternative models include cultural selection, which assumes variant adoption is biased. Theoretical models of human communication argue that during conversation interlocutors are biased to adopt the same labels and other aspects of linguistic representation (including prosody and syntax). This basic alignment mechanism has been extended by computer simulation to account for the emergence of linguistic conventions. When agents are biased to match the linguistic behavior of their interlocutor, a single variant can propagate across an entire population of interacting computer agents. This behavior-matching account operates at the level of the individual. We call it the Conformity-biased model. Under a different selection account, called content-biased selection, functional selection or replicator selection, variant adoption depends upon the intrinsic value of the particular variant (e.g., ease of learning or use). This second alternative account operates at the level of the cultural variant. Following Boyd and Richerson we call it the Content-biased model. The present paper tests the drift model and the two biased selection models' ability to explain the spread of communicative signal variants in an experimental micro-society

The case of PSR J1911-5958A in the outskirts of NGC 6752: signature of a black hole binary in the cluster core?

We have investigated different scenarios for the origin of the binary millisecond pulsar PSR J1911-5958A in NGC 6752, the most distant pulsar discovered from the core of a globular cluster to date. The hypothesis that it results from a truly primordial binary born in the halo calls for accretion-induced collapse and negligible recoil speed at the moment of neutron star formation. Scattering or exchange interactions off cluster stars are not consistent with both the observed orbital period and its offset position. We show that a binary system of two black holes with (unequal) masses in the range of 3-100 solar masses can live in NGC 6752 until present time and can have propelled PSR J1911-5958A into an eccentric peripheral orbit during the last ~1 Gyr.Comment: Accepted by ApJ Letter. 5 pages, 1 figure, 1 tabl

Axisymmetric polydimethysiloxane microchannels for in vitro hemodynamic studies

The current microdevices used for biomedical research are often manufactured using microelectromechanical systems (MEMS) technology. Although it is possible to fabricate precise and reproducible rectangular microchannels using soft lithography techniques, this kind of geometry may not reflect the actual physiology of the microcirculation. Here, we present a simple method to fabricate circular polydimethysiloxane (PDMS) microchannels aiming to mimic an in vivo microvascular environment and suitable for state-of-the-art microscale flow visualization techniques, such as confocal µPIV/PTV. By using a confocal µPTV system individual red blood cells (RBCs) were successfully tracked trough a 75 µm circular PDMS microchannel. The results show that RBC lateral dispersion increases with the volume fraction of RBCs in the solution, i.e. with the hematocrit

Who can spot an online romance scam?

Purpose This paper examines predictors (personality, belief systems, expertise and response time) of detecting online romance scams. Design/methodology/approach The online study asked 261 participants to rate whether a profile was a scam or a genuine profile. Participants were also asked to complete a personality inventory, belief scales, and demographic, descriptive questions. The online study was also designed to measure response time. Findings It was found that those who scored low in romantic beliefs, high in impulsivity, high in consideration of future consequences, had previously spotted a romance scam, and took longer response times, were more likely to accurately distinguish scams from genuine profiles. Notably, the research also found that it was difficult to detect scams. The research also found that it was important to adapt Whitty’s (2013) ‘Scammers Persuasuive Techniques Model’ to include a stage named: ‘human detection of scam versus genuine profiles’. Originality/value This is the first study, to the author’s knowledge, that examines predictors of human accuracy in detecting romance scams. Dating sites and government e-safety sites might draw upon these findings to help improve human detection and protect users from this financial and psychologically harmful cyberscam

The realness of cybercheating : men's and women's representations of unfaithful internet relationships

This paper considers the deviant behaviour of Internet infidelity. Although a plethora of research has been conducted on offline infidelity and jealousy, to date, there has been very little written about Internet infidelity and jealousy associated with cyber-relationships. Given the potential problems that online infidelity might bring to a relationship, this area of research warrants some attention. This study drew from Kitzinger and Powell’s (1995) story completion method in order to explore men and women’s understandings of Internet infidelity. Two hundred and thirty-four participants wrote a story to a cue relating to Internet infidelity. While not all participants saw this as a real act of betrayal the majority did see this as not only real infidelity, but as also having as serious an impact on the couple as a traditional offline affair. The most important finding here was that emotional infidelity was given as much attention as sexual infidelity was. Moreover, similar gender differences found in studies on offline infidelity emerged in this research. These results present a way forward in our thinking about cyber-affairs