M-mode photoacoustic particle flow imaging

Recently, there has been growing interest in the development of photoacoustic flow measuring methods aimed to study microvascular blood flow in biological tissue. Here, we describe the M-mode photoacoustic particle flow imaging, using an optical resolution photoacoustic microscope equipped with a high-repetition-rate pulsed dye laser. We studied the flow of a diluted dyed particle suspension in a small tube embedded in a nonscattering medium as well as in a scattering medium simulating biological tissue. Potentially, the method can be applied to detect the flow speed of single red blood cells in a capillary

Photoacoustic Doppler flowmetry

We report flow measurements based on the photoacoustic Doppler effect. We have performed flow experiments with a suspension of micrometer carbon particles and have detected the photoacoustic Doppler shift at various average flow speeds. We have also observed the directional dependence of the photoacoustic Doppler shift. Our experiment is based on the continuous wave (cw) photoacoustic generation. It is the goal of noninvasively monitoring hemodynamics in functional photoacoustic imaging that motivates our study

Challenges to the DGP Model from Horizon-Scale Growth and Geometry

We conduct a Markov Chain Monte Carlo study of the Dvali-Gabadadze-Porrati (DGP) self-accelerating braneworld scenario given the cosmic microwave background (CMB) anisotropy, supernovae and Hubble constant data by implementing an effective dark energy prescription for modified gravity into a standard Einstein-Boltzmann code. We find no way to alleviate the tension between distance measures and horizon scale growth in this model. Growth alterations due to perturbations propagating into the bulk appear as excess CMB anisotropy at the lowest multipoles. In a flat cosmology, the maximum likelihood DGP model is nominally a 5.3 sigma poorer fit than Lambda CDM. Curvature can reduce the tension between distance measures but only at the expense of exacerbating the problem with growth leading to a 4.8 sigma result that is dominated by the low multipole CMB temperature spectrum. While changing the initial conditions to reduce large scale power can flatten the temperature spectrum, this also suppresses the large angle polarization spectrum in violation of recent results from WMAP5. The failure of this model highlights the power of combining growth and distance measures in cosmology as a test of gravity on the largest scales.Comment: 12 pages, 7 figures, 4 tables, minor revisions reflect PRD published versio

Surface anesthesia of the small incision cataract extraction and intraocular lens implantation

AIM: To observe the effect of cataract extraction and intraocular lens implantation with manual small incision cataract surgery under surface anesthesia in the Primary Hospitals.<p>METHODS: Totally, 372 eyes of 358 cataract cases, in our hospital from January 2010 to March 2013, underwent cataract extraction and intraocular lens implantation with manual small incision cataract surgery under surface anesthesia. Intraoperative pain, postoperative complications and visual acuity were observed.<p>RESULTS: In the process of surgery, patients without pain and being-cooperated were recorded in 342 eyes(91.9%), that occasionally felt slight pain, but within endure and the operation was completed successfully were recorded in 17 eyes(4.6%). There were 13 eyes quit, 8 eyes(2.2%)of them because of the intolerable pain, the other 5 eyes(1.3%)of the ceaseless movement of the eye. The best corrected visual acuity on the 3^rd day after operation of 4.0～4.5 were observed in 57 eyes(15.9%), 4.5～4.8 in 213 eyes(59.3%), above 4.8 in 89 eyes(24.8%).<p>CONCLUSION: The cataract extraction and intraocular lens implantation with manual small incision cataract surgery under surface anesthesia can avoid corresponding complications, reduce the operation time obviously and ensure better quality of operation. It's suitable to carry out the prevention and treatment of blindness at the Primary Hospitals

Anomalous pressure behavior of tangential modes in single-wall carbon nanotubes

Using the molecular dynamics simulations and the force constant model we have studied the Raman-active tangential modes (TMs) of a (10, 0) single-wall carbon nanotube (SWNT) under hydrostatic pressure. With increasing pressure, the atomic motions in the three TMs present obvious diversities. The pressure derivative of E1g, A1g, and E2g mode frequency shows an increased value (), a constant value (), and a negative value () above 5.3 GPa, respectively. The intrinsic characteristics of TMs consumedly help to understand the essence of the experimental T band of CNT. The anomalous pressure behavior of the TMs frequencies may be originated from the tube symmetry alteration from D10h to D2h then to C2h.Comment: 15 pages, 3 pages, submitted to Phys. Rev.

Research on Safety and Security Distance of Flammable Liquid Storage Tank

AbstractFlammable liquid storage tanks usually plant a potential dangerous zone. The damage gets worse and worse. In order to avoid the tank fire, the tanks extended to the nearby storage tanks-facilities and buildings. In consideration of safety conditions, flammable liquid storage tanks for the safety and security distance is necessary. Through the FDS (Fire Dynamics Simulator) computer simulation of fire, flammable liquid storage tanks for spot the fires numerical simulation to detect a fire to happen. In order to establish an optimized model, the flammable liquid storage tanks save the temperature distribution by obtaining flammable safety distance of the liquid storage tank, by talking about the current laws and regulations, by looking forward to meeting the economic and security considerations