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Sojka D.K.,University of Washington | Plougastel-Douglas B.,University of Washington | Yang L.,University of Washington | Pak-Wittel M.A.,University of Washington | And 12 more authors.
eLife | Year: 2014

Natural killer (NK) cells belong to the innate immune system; they can control virus infections and developing tumors by cytotoxicity and producing inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells in the spleen. Recently, we described two populations of liver NK cells, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, their lineage relationship was unclear; trNK cells could be developing cNK cells, related to thymic NK cells, or a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis and transcription factor-deficient mice to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells. Taken together with analysis of trNK cells in other tissues, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells.


Mao X.,Yangzhou University | Sun H.,Yangzhou University | Sun H.,Nanjing University | Wang W.,Yangzhou University | And 4 more authors.
Applied Physics Letters | Year: 2013

Multiferroic properties of four-layered Bi4.25La 0.75Fe0.5Co0.5Ti3O15 ceramics were carefully investigated. X-ray diffraction and high resolution transmission electron microscopy analyses indicate that the as-prepared sample is almost free from secondary phases, and magnetization measurements confirm a ferromagnetic transition ∼483 K. At room temperature (RT), the sample shows a typical ferromagnetism with a remnant magnetization (2Mr) of ∼51.2 m emu/g, and a good ferroelectric hysteresis with a remnant polarization (2Pr) of ∼15.4 μC/cm2. More importantly, an obvious magneto-dielectric (MD) effect has been found under a low magnetic field of 1 T at RT with a maximum of magneto-dielectric constant of ∼10.5%. © 2013 American Institute of Physics.


Wang Z.-Q.,Anhui University of Science and Technology | Zhou J.-H.,Anhui University of Science and Technology | Zhong M.-C.,Anhui University of Science and Technology | Li D.,Anhui University of Science and Technology | And 2 more authors.
Optics Express | Year: 2014

The power spectrum density (PSD) has long been explored for calibrating optical tweezers stiffness. Fast Fourier transform (FFT) based spectral estimator is typically used. This approach requires a relatively longer data acquisition time to achieve adequate spectral resolution. In this paper, an autoregressive (AR) model is proposed to obtain the spectrum density using a limited number of samples. According to our method, the arithmetic model has been established with burg arithmetic, and the final prediction error criterion has been used to select the most appropriate order of the AR model, the power spectrum density has been estimated based the AR model. Then, the optical tweezers stiffness has been determined with the simple calculation from the power spectrum. Since only a small number of samples are used, the data acquisition time is significantly reduced and real-time stiffness calibration becomes feasible. To test this calibration method, we study the variation of the trap stiffness as a function of the parameters of the data length and the trapping depth. Both of the simulation and experiment results have showed that the presented method returns precise results and outperforms the conventional FFT method when using a limited number of samples. © 2014 Optical Society of America.


Kuang S.,Hefei University of Technology | Cong S.,Hefei University of Technology | Cong S.,Hefei National Laboratory for Physical science at the Microscale
Zidonghua Xuebao/Acta Automatica Sinica | Year: 2010

This paper studies the population control problem associated with the equilibrium states of mixed-state quantum systems by using a Lyapunov function with degrees of freedom. The control laws are designed by ensuring the monotonicity of the Lyapunov function; main results on the largest invariant set in the sense of LaSalle are given; and the strict expression of any state in the largest invariant set is normally deduced in the framework of Bloch vectors. By analyzing the obtained largest invariant set and the Lyapunov function itself, this paper also discusses the determination problem of the degrees of freedom. Numerical simulation experiments on a three-level system show the validity of research results. Copyright © 2010 Acta Automatica Sinica. All rights reserved.


Zhou J.-H.,Anhui University of Science and Technology | Zhou J.-H.,Hefei National Laboratory for Physical science at the Microscale | Zhong M.-C.,Anhui University of Science and Technology | Wang Z.-Q.,Anhui University of Science and Technology | And 2 more authors.
Optics Express | Year: 2012

For a triaxial ellipsoid in an optical trap with spherical aberration, the optical forces, torque and stress are analyzed using vectorial ray tracing. The torque will automatically regulate ellipsoid's long axis parallel to optic axis. For a trapped ellipsoid with principal axes in the ratio 1:2:3, the high stress distribution appears in x-z plane. And the optical force at x-Axis is weaker than at y-Axis due to the shape size. While the ellipsoid departs laterally from trap center, the measurable maximum transverse forces will be weakened due to axial equilibrium and affected by inclined orientation. For an appropriate ring beam, the maximum optical forces are strong in three dimensions, thus, this optical trap is appropriate to trap cells for avoiding damage from laser. © 2012 Optical Society of America.


Qiu Y.,Hefei National Laboratory for Physical science at the Microscale | Qiu Y.,Anhui University of Science and Technology | Liu L.,Hefei National Laboratory for Physical science at the Microscale | Liu L.,Anhui University of Science and Technology | And 18 more authors.
Genes and Development | Year: 2012

Histone acetylation is a hallmark for gene transcription. As a histone acetyltransferase, MOZ (monocytic leukemia zinc finger protein) is important for HOX gene expression as well as embryo and postnatal development. In vivo, MOZ forms a tetrameric complex with other subunits, including several chromatin-binding modules with regulatory functions. Here we report the solution structure of the tandem PHD (plant homeodomain) finger (PHD12) of human MOZ in a free state and the 1.47 Å crystal structure in complex with H3K14ac peptide, which reveals the structural basis for the recognition of unmodified R2 and acetylated K14 on histone H3. Moreover, the results of chromatin immunoprecipitation (ChIP) and RT-PCR assays indicate that D12 facilitates the localization of MOZ onto the promoter locus of the HOXA9 gene, thereby promoting the H3 acetylation around the promoter region and further up-regulating the HOXA9 mRNA level. Taken together, our findings suggest that the combinatorial readout of the H3R2/K14ac by PHD12 might represent an important epigenetic regulatory mechanism that governs transcription and also provide a clue of cross-talk between the MOZ complex and histone H3 modifications. © 2012 by Cold Spring Harbor Laboratory Press.


Ge W.,CAS Hefei Key Laboratory of Materials for Energy Conversion | Zhang X.R.,Hefei National Laboratory for Physical science at the Microscale | Liu M.,CAS Hefei Key Laboratory of Materials for Energy Conversion | Lei Z.W.,CAS Hefei Key Laboratory of Materials for Energy Conversion | And 4 more authors.
Theranostics | Year: 2013

We report a localized surface plasmon enhanced upconversion luminescence in Au/SiO2/Y2O3:Yb3+,Er3+ nanoparticles when excited at 980 nm. By adjusting the silica spacer's thickness, a maximum 9.59-fold enhancement of the green emission was obtained. Effect of the spacer distance on the Au-Y2O3:Yb3+, Er3+ green upconversion mechanism was numerically sim-ulated and experimentally demonstrated. In theory for radiative decay and excitation rates, they can be largely enhanced at the spacer thicknesses of less than 70 and 75 nm, respectively, and the quenching can be caused by the non-radiative energy transferring at the distance of less than 55 nm. © Ivyspring International Publisher.


Cheng W.,Hefei National Laboratory for Physical science at the Microscale | Cheng W.,Hefei University of Technology | Tang K.,Hefei National Laboratory for Physical science at the Microscale | Tang K.,Hefei University of Technology | And 2 more authors.
Chemistry - A European Journal | Year: 2010

(Figure Presented) From green to red: Highly water-soluble superparamagnetic monodisperse ferrite colloidal spheres with tunable size and composition have been prepared by a simple one-step hydrothermal method. The zinc ferrite colloidal spheres show composition-dependent saturation magnetization. Surprisingly, the Z 0.41Fe 0.59Fe 2O 4 colloidal sphere aqueous suspension can be used for constructing photonic crystals (see figure). © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.


Li W.-Q.,Anhui University of Science and Technology | Sun C.-Y.,Anhui University of Science and Technology | Wang F.,Hefei National Laboratory for Physical science at the Microscale | Wang Y.-C.,Hefei National Laboratory for Physical science at the Microscale | And 8 more authors.
Nano Letters | Year: 2013

During the process of human civilization, owning household pets has become increasingly popular. However, dogs and cats may be reservoirs or vectors of transmissible diseases to humans. Confronted with the overpopulation of pets, traditional contraception methods, surgical methods of sterilization, for animals are used, namely, ovariohysterectomy and orchidectomy. Therefore, a simple, nonsurgical, controllable, more effective and less expensive contraception method is highly desirable. In this study, we show that in situ testicular injection of methoxy poly(ethylene glycol)-modified gold nanorods with near-infrared irradiation in male mice can achieve short-lived or permanent male infertility. In a lower hyperthermia treatment, the morphology of testes and seminiferous tubules is only partly injured, and fertility indices are decreased to ∼10% at day 7, then recovered to 50% at day 60. In a higher hyperthermia treatment, the morphology of testes and seminiferous tubules are totally destroyed, and fertility indices are decreased to 0 at day 7. Overall, our results indicate a potential application of plasmonic nanomaterials for male contraception. © 2013 American Chemical Society.


Lou Y.,Hefei University of Technology | Cong S.,Hefei University of Technology | Cong S.,Hefei National Laboratory for Physical science at the Microscale | Yang J.,Hefei University of Technology | Kuang S.,Hefei University of Technology
IET Control Theory and Applications | Year: 2011

The state transfer of closed quantum systems in the interaction picture is studied. The convergent problem encountered in designing control laws based on the Lyapunov method is solved by the well constructed observable operator and a path programming control strategy. It is proved that the condition for the target state being a stable point in the Lyapunov's sense is the coherent vectors of the observable operator and the target state must be in opposite directions. For the local optimisation limitation of the Lyapunov-based method, the path programming control strategy is proposed, which is used to change the distribution of stationary points or choose a transition path by appropriately selecting intermediate target states. Comparative numerical system simulation experiments are implemented on a four-level quantum system and the experimental results are analysed. © 2011 The Institution of Engineering and Technology.

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