Edge and bulk merons in double quantum dots with spontaneous interlayer phase coherence

We have investigated nucleation of merons in double quantum dots when a lateral distortion with a reflection symmetry is present in the confinement potential. We find that merons can nucleate both inside and at the edge of the dots. In addition to these merons, our results show that electron density modulations can be also present inside the dots. An edge meron appears to have approximately a half integer winding number.Comment: 5 pages, 4 figures, Proceedings of 17th International Conference on High Magnetic Fields in Semiconductor Physic

Impact of court decisions on the future of diagnostics and personalized medicine

Intellectual property protection in the form of secured patents has played an integral role in the growth and advancement of the biotechnology industry. The protection of intellectual properties is considered very important asset in this evolving industry. As a result, patent disputes often end up in the courts with long lasting consequences. Here we examined two recent and highly publicized patent dispute cases, namely, Mayo Collaborative Services et al. v. Prometheus Laboratories, Inc. (2012) and Association for Molecular Pathology et al. v. Myriad Genetics (2011), and wish to assess how the rulings will impact diagnostics and personalized medicine industries. In doing so, we learned that decisions involving patents are complex and interconnected, with previous court rulings influencing subsequent cases. It also became clear that in general, the biotechnology industry favored patent protection while healthcare providers and their patients favored less stringent patent protection. The case is made by the biotechnology industry that the current system has allowed both the diagnostics and personalized medicine industries to flourish. Patents are a crucial incentive that not only promotes but also protects innovation. Any disruption on the legal front with regards to patents will have a negative effect. On the other hand, healthcare providers and their patients voiced their concerns that the current system limits the affordability and accessibility of healthcare. Patent protected drugs are often expensive, making it difficult for some patients to afford. In addition, these drugs have no generic counterparts and are often without alternatives, limiting their accessibility. The providers and their patients argue that relaxing the current regulations is needed and that doing so will not impact innovation. It is believed that increased competition will have a two-fold effect—driving down prices and forcing innovation as a means of differentiation. In the end, the decisions themselves have provided little guidance regarding how the biotechnology industry should proceed, but this much is clear—a balance needs to be struck between the two opposing viewpoints for the biotech industry to survive and continue to grow

Hole maximum density droplets of an antidot in strong magnetic fields

We investigate a quantum antidot in the integer quantum Hall regime (the filling factor is two) by using a Hartree-Fock approach and by transforming the electron antidot into a system which confines holes via an electron-hole transformation. We find that its ground state is the maximum density droplet of holes in certain parameter ranges. The competition between electron-electron interactions and the confinement potential governs the properties of the hole droplet such as its spin configuration. The ground-state transitions between the droplets with different spin configurations occur as magnetic field varies. For a bell-shape antidot containing about 300 holes, the features of the transitions are in good agreement with the predictions of a recently proposed capacitive interaction model for antidots as well as recent experimental observations. We show this agreement by obtaining the parameters of the capacitive interaction model from the Hartree-Fock results. An inverse parabolic antidot is also studied. Its ground-state transitions, however, display different magnetic-field dependence from that of a bell-shape antidot. Our study demonstrates that the shape of antidot potential affects its physical properties significantly.Comment: 12 pages, 11 figure

Bifurcations and nonlinear dynamics of the follower force model for active filaments

Biofilament-motor protein complexes are ubiquitous in biology and drive the transport of cargo vital for many fundamental cellular processes. As they move, motor proteins exert compressive forces on the filaments to which they are attached, leading to buckling and a subsequent range of dynamics. The follower force model, in which a single compressive force is imposed at the filament tip, is the standard and most basic model for an elastic filament, such as a microtubule, driven by a motor protein. Depending on the force value, one can observe different states including whirling, beating and writhing, though the bifurcations giving rise to these states are not completely understood. In this paper, we utilise techniques from computational dynamical systems to determine and characterise these bifurcations. We track emerging time-periodic branches and identify new, quasiperiodic states. We investigate the effect of filament slenderness on the bifurcations and, in doing so, present a comprehensive overview of the dynamics which emerge in the follower force model.Comment: 34 pages, 9 figure

Single electron control in n-type semiconductor quantum dots using non-Abelian holonomies generated by spin orbit coupling

We propose that n-type semiconductor quantum dots with the Rashba and Dresselhaus spin orbit interactions may be used for single electron manipulation through adiabatic transformations between degenerate states. All the energy levels are discrete in quantum dots and possess a double degeneracy due to time reversal symmetryin the presence of the Rashba and/or Dresselhaus spin orbit coupling terms. We find that the presence of double degeneracy does not necessarily give rise to a finite non-Abelian (matrix) Berry phase. We show that a distorted two-dimensional harmonic potential may give rise to non-Abelian Berry phases. The presence of the non-Abelian Berry phase may be tested experimentally by measuring the optical dipole transitions.Comment: accepted in Phys. Rev.

A Review and Case Exemplifications of Health Enhancement Lifestyle Profile (HELP) and Its Screener (HELP–Screener) for Older Adults

Growing interest in promoting healthy lifestyles as a way to enhance successful aging has led to the necessity of screening and monitoring lifestyle behaviors among older adults. The 56-item Health Enhancement Lifestyle Profile (HELP) and its screening version, the 15-item HELP-Screener are a set of instruments designed for assessing various health-related lifestyle behaviors in older adults, including exercise, diet, social and productive activities, leisure, activities of daily living, stress management and spiritual participation, and other health promotion and risk behaviors. This article depicts the critical features (e.g., administration and scoring) and clinical usefulness of the two instruments and reviews the literature that supports the instruments\u27 psychometric properties (e.g., reliability and validity). Two case studies are also provided for exemplifying the clinical application of the tools. Occupational therapists can use the brief HELP-Screener for determining clients\u27 need for further evaluation with the 56-item HELP wherein scrutiny of diverse lifestyle behaviors and consultation of possible health-promoting strategies can take place

Primary immune thrombocytopenia responding to antithyroid treatment in a patient with Graves’ disease

published_or_final_versionSpringer Open Choice, 21 Feb 201