Free spectral range electrical tuning of a high quality on-chip microcavity

Reconfigurable photonic circuits have applications ranging from next-generation computer architectures to quantum networks, coherent radar and optical metamaterials. However, complete reconfigurability is only currently practical on millimetre-scale device footprints. Here, we overcome this barrier by developing an on-chip high quality microcavity with resonances that can be electrically tuned across a full free spectral range (FSR). FSR tuning allows resonance with any source or emitter, or between any number of networked microcavities. We achieve it by integrating nanoelectronic actuation with strong optomechanical interactions that create a highly strain-dependent effective refractive index. This allows low voltages and sub-nanowatt power consumption. We demonstrate a basic reconfigurable photonic network, bringing the microcavity into resonance with an arbitrary mode of a microtoroidal optical cavity across a telecommunications fibre link. Our results have applications beyond photonic circuits, including widely tuneable integrated lasers, reconfigurable optical filters for telecommunications and astronomy, and on-chip sensor networks.Comment: Main text: 7 pages, 3 figures. Supplementary information: 7 pages, 9 figure

(Z)-1-Phenyl-3-(3-pyridyl­meth­ylamino)­but-2-en-1-one

The reaction of 3-C5H4NCH2NH2 and C6H5COCH2COCH3 affords the title compound, C16H16N2O. The O=C—C=C—N portion is essentially planar [maximum deviation = 0.046 (2) Å] and is aligned at dihedral angles of 22.6 (1) and 78.9 (1)° to the phenyl and pyridyl rings, respectively. The N—H and O=C groups are linked by an intra­molecular hydrogen bond. In the crystal, C—H⋯O hydrogen bonds and C—H⋯π inter­actions occur

Multifunctional Nanocarriers for Cancer Therapy

Cancer is one of the leading causes of human mortality and mortality in all diseases. There has been a boost in developing nanocarrier-based therapies for treating cancer or other diseases during the past decade. One of the major advantages about nanocarrier (with the size range from 1-1000 nm) lies in its ability to specifically target tumor and maximize drug accumulation in tumor foci through the enhanced permeability and retention effect. Advancement in nanotechnology has opened a new paradigm in pharmaceutical field. But new challenges have to be overcome in order to fully exploit the technology and improve safety in clinical application. To improve their performance, at least two types of multifunctional nanocarriers are being developed in our lab. The first type of nanocarrier is glycol chitosan based polymer delivery system, which is a one-step preparation system, with excellent loading capacity. We can use the nanocarrier to guide its loading cargo such as anticancer agents to release in a particular subcellular location, or to load multiple drugs together to increase therapeutic efficacy. The other system is a gold nanoparticle gated mesoporous silica hybrid system, by which we are able to simultaneously execute multiple anticancer therapies such as the combination of photothermal therapy and chemotherapy. Compared with the first generation of nano-delivery system, our new nanocarrier enters cells more efficiently through sigma 2 receptors. Moreover, it can serve as a diagnostic tool through PET (Positron emission tomography), and our study shows that it is able to detect all the spontaneously lung tumors. We believe that these multifunctional nanocarriers have the potential benefits in various areas of current pharmaceutical research including cancer diagnosis and treatment

Effect of acupressure on postpartum low back pain, salivary cortisol, physical limitations, and depression: a randomized controlled pilot study

Objective: To investigate the effect of acupressure on postpartum low back pain (LBP), salivary cortisol, physical limitations, and postpartum depression. Methods: Participants were 70 postpartum women who were randomly assigned to either an intervention (n = 35) or a control (n = 35) group. The intervention group received 10 acupressure sessions (1 session per day, 5 d per week). The control group received 10 sham acupressure sessions. Outcomes were assessed using a visual analogue scale (LBP intensity), salivary cortisol values (LBP biomarker), and Chinese versions of the Roland-Morris Disability Questionnaire (daily activity limitations), Oswestry Disability Index (physical activity limitations), and the Edinburgh Postnatal Depression Scale (postpartum depression). Results: Participants in the intervention group had significantly lower levels of LBP intensity, daily activity limitations, physical activity limitations, and postpartum depression than those in the control group. There was no significant between-group difference in salivary cortisol. Conclusion: Acupressure may reduce postpartum LBP intensity and limitations in daily and physical activity, and alleviate postpartum depressive symptoms. Acupressure should be offered in postpartum care settings as an alternative treatment for postpartum women with LBP

TaintTrace: Efficient Flow Tracing with Dynamic Binary Rewriting

TaintTrace is a high performance flow tracing tool that protects systems against security exploits. It is based on dynamic execution binary rewriting empowering our tool with fine-grained monitoring of system activities such as the tracking of the usage and propagation of data origi-nated from the network. The challenge lies in minimizing the run-time overhead of the tool. TaintTrace uses a number of techniques such as direct memory mapping to optimize performance. In this paper, we demonstrate that TaintTrace is effective in protecting against various attacks while main-taining a modest slowdown of 5.5 times, offering significant improvements over similar tools.

An approach for tool health assessment using the Mahalanobis-Taguchi system based on WPT-AR

A real-time tool health assessment has a significant implication on reliable machining operations. This paper proposes a health assessment method for tools in milling machine using the Mahalanobis-Taguchi system (MTS) based on wavelet packet transformation and autoregression. In this method, the nonlinear and non-stationary vibration signal from the milling process is first decomposed using wavelet packet transforms. Then, an autoregression (AR) model is constructed for each coefficient of the reconstructed signal, and the parameters as well as variance of the remnants of each AR model are employed to form the initial feature matrix. Singular values of this feature matrix are obtained through singular value decomposition, at which point MTS is employed. In this study, MTS provides (1) a computational scheme based on the Mahalanobis distance for obtaining the health index of a tool, and (2) Taguchi methods to extract the key features and reduce the redundant ones. Finally, the performance and effectiveness of the proposed method are validated by vibration signals acquired from the milling machining process

Redox-Sensitive Nanocomplex for Targeted Delivery of Melittin

Although peptide therapeutics have been explored for decades, the successful delivery of potent peptides in vitro and in vivo remains challenging due to the poor stability, low cell permeability, and off-target effects. We developed a redox sensitive polymer-based nanocomplex which can efficiently and stably deliver the peptide drug melittin for cancer therapy. The nanocomplex selectively targets cancer cells through lactobionic acid mediated endocytosis and releases melittin intracellularly upon the trigger of elevated redox potential. In vivo study proved that the targeted nanocomplex shows excellent potency in inhibiting tumor growth in a xenograft colon cancer mouse model. Thus, the polymer/melittin nanocomplexes will provide a new approach for melittin based cancer therapy

Tensor product representation of topological ordered phase: necessary symmetry conditions

The tensor product representation of quantum states leads to a promising variational approach to study quantum phase and quantum phase transitions, especially topological ordered phases which are impossible to handle with conventional methods due to their long range entanglement. However, an important issue arises when we use tensor product states (TPS) as variational states to find the ground state of a Hamiltonian: can arbitrary variations in the tensors that represent ground state of a Hamiltonian be induced by local perturbations to the Hamiltonian? Starting from a tensor product state which is the exact ground state of a Hamiltonian with $\mathbb{Z}_2$ topological order, we show that, surprisingly, not all variations of the tensors correspond to the variation of the ground state caused by local perturbations of the Hamiltonian. Even in the absence of any symmetry requirement of the perturbed Hamiltonian, one necessary condition for the variations of the tensors to be physical is that they respect certain $\mathbb{Z}_2$ symmetry. We support this claim by calculating explicitly the change in topological entanglement entropy with different variations in the tensors. This finding will provide important guidance to numerical variational study of topological phase and phase transitions. It is also a crucial step in using TPS to study universal properties of a quantum phase and its topological order.Comment: 10 pages, 6 figure