Efficacy of Lagopsis supina to promote blood circulation, remove blood stasis, and block inflammation in a rat model of traumatic blood stasis

Lagopsis supina (Steph) IK. Gal. was a traditional Chinese medicinal plant for promoting blood circulation and removing blood stasis (PBCRBS), anti-inflammatory and diuresis with little scientific validation. The aims of this study were first to evaluate the PBCRBS and anti-inflammatory effects of L. supina in a rat model of traumatic blood stasis (TBS). We demonstrated that an ethanolic extract of L. supina (LS, 460 mg/kg/d) possessed significant PBCRBS and remarkable inhibitory effect on inflammation cytokines, which were associated with renovated amount of the injured muscle fibers, alleviate the degree of the damaged tissue edema, decreased the number of inflammatory cells, increased the number of the capillary hyperplasia by hematoxylin and eosin (HE), as well as remarkably down-regulated ( p < 0.05 or p < 0.01) the levels of inflammation cytokines, including TNF-α, IL-6, IL-8, and IL-10 by ELISA. This finding provide a pharmacological basis and partial interpretation for the clinical application of L. supina, which has therapeutic properties for blood stasis syndrome (BSS) and inflammation-related diseases

Self-Transducing Silicon Nanowire Electromechanical Systems at Room Temperature

Electronic readout of the motions of genuinely nanoscale mechanical devices at room temperature imposes an important challenge for the integration and application of nanoelectromechanical systems (NEMS). Here, we report the first experiments on piezoresistively transduced very high frequency Si nanowire (SiNW) resonators with on-chip electronic actuation at room temperature. We have demonstrated that, for very thin (∼90 nm down to ∼30 nm) SiNWs, their time-varying strain can be exploited for self-transducing the devices’ resonant motions at frequencies as high as ∼100 MHz. The strain of wire elongation, which is only second-order in doubly clamped structures, enables efficient displacement transducer because of the enhanced piezoresistance effect in these SiNWs. This intrinsically integrated transducer is uniquely suited for a class of very thin wires and beams where metallization and multilayer complex patterning on devices become impractical. The 30 nm thin SiNW NEMS offer exceptional mass sensitivities in the subzeptogram range. This demonstration makes it promising to advance toward NEMS sensors based on ultrathin and even molecular-scale SiNWs, and their monolithic integration with microelectronics on the same chip

Flexible semi-conductor devices in microstructured optical fibers for integrated optoelectronics

Here we present a novel group of flexible semiconductor electronic/optoelectronic devices made in microstructured optical fibers with extreme aspect ratios. These devices are motivated by incorporating the optoelectronic capabilities of semiconductor structures into optical fibers, the backbone for the modern optical communications. The joint of these two key techniques could enable all-fiber networks, in which light generation, modulation, transmission, and detection can all be performed within a fiber. One very important merit that makes optical fibers so practical in long distance communications is that they are very strong and flexible. The semiconductor materials and structures are thereby required to have comparable strengths and flexibilities, if constructed inside the fibers to realize unprecedented optoelectronics functions. Microstructured optical fibers have a complex two dimensional structure of air holes running down the length. We have demonstrated infiltration of a variety of semiconductor materials into the holes via the unique high pressure chemical vapor deposition. In this presentation, we first report the control of the carrier type and concentration in Si and Ge. Based on this control, we are able to make different types of field effect transistors and realize Si/Ge pn junctions in a fiber for the first time. This should be of considerable significance since pn junctions are the basic building blocks for optoelectronics. For example, our preliminary results show that Si/Ge heterojunctions work as in-fiber photodetectors for the 1.55 µm communication light. In the presentation, we will particularly address the flexibility of these in-fiber devices. These devices are wires or tubes with diameters ranging from 0.5 to 10 µm and lengths up to several tens of centimeters. Although being of polycrystalline nature, they show remarkable flexibilities, for example, they can generally stand > 1% strain without breaking. Generally, single crystalline whiskers and nanowires have proven to have strengths close to the theoretical values. The study of the mechanical behavior of these fine grained semiconductor materials should be highly worthwhile; they may expand the material choice for the flexible electronics and optoelectronics

Very High Frequency Silicon Nanowire Electromechanical Resonators

We demonstrate very high frequency (VHF) nanomechanical resonators based upon single-crystal silicon nanowires (SiNWs), which are prepared by the bottom-up chemical synthesis. Metallized SiNW resonators operating near 200 MHz are realized with quality factor Q ≈ 2000−2500. Pristine SiNWs, with fundamental resonances as high as 215 MHz, are measured using a VHF readout technique that is optimized for these high resistance devices. The pristine resonators provide the highest Q's, as high as Q ≈ 13 100 for an 80 MHz device. SiNWs excel at mass sensing; characterization of their mass responsivity and frequency stability demonstrates sensitivities approaching 10 zeptograms. These SiNW resonators offer significant potential for applications in resonant sensing, quantum electromechanical systems, and high frequency signal processing