Electrically Tunable Reflective Metasurfaces with Continuous and Full-Phase Modulation for High-Efficiency Wavefront Control at Visible Frequencies.

All-dielectric optical metasurfaces can locally control the amplitude and phase of light at the nanoscale, enabling arbitrary wavefront shaping. However, lack of postfabrication tunability has limited the true potential of metasurfaces for many applications. Here, we utilize a thin liquid crystal (LC) layer as a tunable medium surrounding the metasurface to achieve a phase-only spatial light modulator (SLM) with high reflection in the visible frequency, exhibiting active and continuous resonance tuning with associated 2π phase control and uncoupled amplitude.

High resolution multispectral spatial light modulators based on tunable Fabry-Perot nanocavities.

Spatial light modulators (SLMs) are the most relevant technology for dynamic wavefront manipulation. They find diverse applications ranging from novel displays to optical and quantum communications. Among commercial SLMs for phase modulation, Liquid Crystal on Silicon (LCoS) offers the smallest pixel size and, thus, the most precise phase mapping and largest field of view (FOV).

Near unity transmission and full phase control with asymmetric Huygens' dielectric metasurfaces for holographic projections.

Huygens' metasurfaces are transparent arrays of nanostructures that enable phase-front manipulation. This is achieved by simultaneous excitation of electric dipole (ED) and magnetic dipole (MD) resonances with equal amplitudes and phases in the constituent meta-atoms. In usual designs, the size changes of the meta-atoms, necessary to map the phase front, can detune the overlapping of ED and MD resonances, decreasing the transmission and limiting the operating bandwidth.

Efficient visible light modulation based on electrically tunable all dielectric metasurfaces embedded in thin-layer nematic liquid crystals.

All-dielectric metasurfaces have attracted attention for highly efficient visible light manipulation. So far, however, they are mostly passive devices, while those allowing dynamic control remain a challenge. A highly efficient tuning mechanism is immersing the metasurface in a birefringent liquid crystal (LC), whose refractive index can be electrically controlled.

Phase-only transmissive spatial light modulator based on tunable dielectric metasurface.

Rapidly developing augmented reality, solid-state light detection and ranging (LIDAR), and holographic display technologies require spatial light modulators (SLMs) with high resolution and viewing angle to satisfy increasing customer demands. Performance of currently available SLMs is limited by their large pixel sizes on the order of several micrometers. Here, we propose a concept of tunable dielectric metasurfaces modulated by liquid crystal, which can provide abrupt phase change, thus enabling pixel-size miniaturization.

Transgenic increase in the β-endorphin concentration in cerebrospinal fluid alleviates morphine-primed relapse behavior through the μ opioid receptor in rats.

Background: Opioid-primed relapse is a global burden. Although current strategies have improved, optimal therapy is urgently needed.

Methods: A recombinant adenovirus (Ad-NEP) expressing β-endorphin (β-EP) was designed and injected intracerebroventricularly (icv) into the right lateral ventricle in rats.

Efficacy and Safety of Opioids for the Prevention of Etomidate-Induced Myoclonus: A Meta-Analysis.

Etomidate is a widely used hypnotic drug for induction of general anesthesia and sedation, especially in elderly patients and hemodynamically unstable patients. Myoclonus, however, is the most prominent problem during induction of anesthesia with etomidate. Many agents have been used to prevent it and opioid is one of them.

Fast distributed large-pixel-count hologram computation using a GPU cluster.

Large-pixel-count holograms are one essential part for big size holographic three-dimensional (3D) display, but the generation of such holograms is computationally demanding. In order to address this issue, we have built a graphics processing unit (GPU) cluster with 32.5 Tflop/s computing power and implemented distributed hologram computation on it with speed improvement techniques, such as shared memory on GPU, GPU level adaptive load balancing, and node level load distribution.

Effect of recombinant adenovirus coding for endomorphin-2 on neuropathic pain in rats.

Objective: To construct a transgene expressing human endomorphin-2 by linking the signal peptide of mouse nerve growth factor (PN) to a human endomorphin-2 DNA sequence containing a short linker recognized by the protease FURIN and test the analgesic effect of endomorphin-2 on neuropathic pain.

Methods: The transgene was inserted into the cosmid pAxCAwt to generate PN-EM-2-pAxCAwt. The recombinant adenovirus Ad-PNEM2 was packaged and propagated in HEK293 cells.

Suppression of acute morphine withdrawal syndrome by adenovirus-mediated β-endorphin in rats.

Background: Endogenous β-endorphin (β-EP) in the central nervous system (CNS) is decreased upon opioid addiction. The current study examined whether exogenous β-EP, delivered using an adenoviral vector into the CNS could attenuate morphine withdrawal syndrome in rats.

Methods: The model of opioid-dependent rats was set up by receiving subcutaneous injection of morphine using an escalating regimen for 6days (5, 10, 20, 40, 50, 60mg/kg, three times/day).

Intrathecal siRNA against Toll-like receptor 4 reduces nociception in a rat model of neuropathic pain.

Background: Neuropathic pain is characterized by hyperalgesia, allodynia and spontaneous pain. It often occurs as a result of injury to peripheral nerves, dorsal root ganglions (DRG), spinal cord, or brain. Recent studies have suggested that Toll-like receptor 4 (TLR4) might play a role in neuropathic pain.

Fast CGH computation using S-LUT on GPU.

In computation of full-parallax computer-generated hologram (CGH), balance between speed and memory usage is always the core of algorithm development. To solve the speed problem of coherent ray trace (CRT) algorithm and memory problem of look-up table (LUT) algorithm without sacrificing reconstructed object quality, we develop a novel algorithm with split look-up tables (S-LUT) and implement it on graphics processing unit (GPU). Our results show that S-LUT on GPU has the fastest speed among all the algorithms investigated in this paper, while it still maintaining low memory usage.

Regular effective hologram regions for computer generated holography.

An effective hologram region (EHR) based approach is presented to speed up the computation of computer generated holograms (CGHs). The object space is predivided into subspaces, and an EHR for each subspace is predefined according to the maximum spatial frequency of interference fringes, light diffraction efficiency, and CGH binarization effect. To compute the hologram of an object, the object points are first categorized according to which subspace they are located in, and then their holograms are calculated using the corresponding EHRs.

Human signal peptide had advantage over mouse in secretory expression.

The signal peptide is a critical component in the secretory expression of protein in eukaryotic cells. It has been verified that the signal peptide of mouse nerve growth factor could mediate the secretory expression of beta-endorphin in cultured non-neuronal cells. Although there is a counterpart of nerve growth factor in human genome, no research about the signal sequence from human genome has been reported.

[Construction and analysis of in vitro expression of adenovirus/adeno-associated hybrid virus containing the fusion gene of human beta-endorphin].

The fusion gene of human beta-endorphin was cloned into the shuttle plasmid pDC312-AAVEE with the method of molecular bilology. The latter and genomic plasmids were cotransfected into HEK293 to package the Adenovirus/Adeno-associated hybrid virus containing fusion gene of human beta-endorphin. The hybrid virus was identified with the method of PCR.

[Experimental study of compatibility between chondrocytes and allogenic cartilage microparticle acellular tissue matris in vitro].

Objective: To construct tissue engineered cartilage using cartilage microparticle acellular tissue matrix (CMACTM) as scaffold.

Methods: To determine the content of hydroxyproline, glycosaminoglycan and DNA of CMACTM prepared from sheep's articular cartilage with multistep enzymic method, and to analyze CMACTM with gross observation, histology and scanning electron microscopy. Allogenic chondrocytes were mixed with CMACTM and cultured in vitro from 0 to 35 days.

Deterministic beam fanning in Fe-doped stoichiometric lithium niobate crystals.

We investigated the beam-fanning effect in Fe-doped stoichiometric lithium niobate (Fe:SLN) crystals that were grown by the top-seeded solution growth method. Deterministic beam fanning (DBF) was measured in Z-cut Fe:SLN crystal for incident light propagating along the c+ and c- axes. The dependence of beam-fanning factors on incident power density was also studied.

[Transferring neurovascular rectus femoris muscle segment for treatment of facial paralysis].

Objective: To investigate a new technique for functional treatment of chronic facial paralysis.

Methods: Based on anatomy of intramuscular neurovascular structure in the rectus femoris muscle, 7 consecutive patients with facial paralysis were treated by using a technique of microsurgically free-transferring neurovascular rectus femoris muscle segment to the face in one-stage. Follow-ups were 10 to 24 months.

[The neurovascular anatomy and its clinical implication of the rectus femoris muscle].

Objective: The objective of this anatomic study was to investigate the intramuscular neurovascular configuration and to evaluate whether the muscle could be split into two functional units in transplantation.

Methods: Ten fresh cadavers and ten preserved cadavers were used in the study. A mixture of lead oxide, gelatin and water was injected to the femoral artery of the fresh cadaver.