Realization of universal nonadiabatic geometric control on decoherence-free qubits in the XY model

A fundamental requirement of quantum information processing is the protection from the adverse effects of decoherence and noise. Decoherence-free subspaces and geometric processing are important steps of quantum information protection. Here, we provide a new experimentally feasible scheme to combine decoherence-free subspaces with nonadiabatic geometric manipulations to attain a universal quantum computation. The proposed scheme is different from previous proposals and is based on the typical XY interaction coupling, which can be set up in various nano-engineered systems and therefore open up for realization of nonadiabatic holonomic quantum computation in decoherence-free subspaces.Comment: 21 pages, 5 figure

Higher nucleoporin-Importinβ affinity at the nuclear basket increases nucleocytoplasmic import.

Several in vitro studies have shown the presence of an affinity gradient in nuclear pore complex proteins for the import receptor Importinβ, at least partially contributing to nucleocytoplasmic transport, while others have historically argued against the presence of such a gradient. Nonetheless, the existence of an affinity gradient has remained an uncharacterized contributing factor. To shed light on the affinity gradient theory and better characterize how the existence of such an affinity gradient between the nuclear pore and the import receptor may influence the nucleocytoplasmic traffic, we have developed a general-purpose agent based modeling (ABM) framework that features a new method for relating rate constants to molecular binding and unbinding probabilities, and used our ABM approach to quantify the effects of a wide range of forward and reverse nucleoporin-Importinβ affinity gradients. Our results indicate that transport through the nuclear pore complex is maximized with an effective macroscopic affinity gradient of 2000 µM, 200 µM and 10 µM in the cytoplasmic, central channel and nuclear basket respectively. The transport rate at this gradient is approximately 10% higher than the transport rate for a comparable pore lacking any affinity gradient, which has a peak transport rate when all nucleoporins have an affinity of 200 µM for Importinβ. Furthermore, this optimal ratio of affinity gradients is representative of the ratio of affinities reported for the yeast nuclear pore complex--suggesting that the affinity gradient seen in vitro is highly optimized

An In Vitro 3D Model to Evaluate Behaviour of Breast Cancer Cells and Response to Treatment

The field of 3D culture models of disease has started to move towards systems that aim to recapitulate the complexity of human tissues. However, despite recent improvements, current 3D systems remain overly simplistic, lacking the biophysical characteristics and diverse structures found in most organs. In this project, the cellular behaviour of breast cancer and their responsiveness to chemotherapeutic agents were evaluated under different 3D cell culture conditions. MDA-MB231 and SKBR3 cells were prepared as spheroids using ultra-low attachment plates and as 'artificial cancer masses' (ACM) by embedding cells in a dense collagen type-I. The ACMs were maintained under flow (150 μL/min) and flow/pressure (550 μL/min, ~19 mmHg) conditions. A significant reduction in cell viability was observed when cancer cells were grown as ACM compared to 2D culture. Cell viability also declined significantly when ACMs were maintained in flow/pressure condition compared to static condition. Similarly, an increase in the expression levels of markers of EMT was observed when cells were cultured as ACM. However, compared to static 3D incorporation of flow and pressure was associated with decreased expression levels of vimentin, HIF1-α, whilst MMP14 expression increased and snail remained unchanged. HER2 levels were increased in SKBR3 when the cells were cultured under flow/pressure (1.5 fold) compared to static condition. Overall, cells cultured as ACMs exhibited reduced responsiveness to doxorubicin compared to those grown in the conventional 2D culture. A decrease sensitivity was also observed in 3D/flow/pressure and 3D/flow compared to 3D/static condition. The results obtained in this study show that cancer cell behaviour and their response to therapeutic agents are affected by different microenvironments. Therefore, a new generation of 3D in vitro models need to be developed as pre-clinical drug testing platforms