5,362 research outputs found
Continuous-variable controlled-Z gate using an atomic ensemble
The continuous-variable controlled-Z gate is a canonical two-mode gate for
universal continuous-variable quantum computation. It is considered as one of
the most fundamental continuous-variable quantum gates. Here we present a
scheme for realizing continuous-variable controlled-Z gate between two optical
beams using an atomic ensemble. The gate is performed by simply sending the two
beams propagating in two orthogonal directions twice through a spin-squeezed
atomic medium. Its fidelity can run up to one if the input atomic state is
infinitely squeezed. Considering the noise effects due to atomic decoherence
and light losses, we show that the observed fidelities of the scheme are still
quite high within presently available techniques.Comment: 7 pages, 3 figures, to appear in Physical Review
Assessment of genetic relationships among Spring Dendrobium cultivars and varietal materials using amplified fragment length polymorphism (AFLP) analysis
Spring Dendrobiums have been largely produced as one of the top grade ornamental pot plants due to their various flower colors, multitudinous flowers and graceful flower shape as well as their long period of florescence. Genetic relationships among Spring Dendrobium cultivars, however, have not been documented. This study analyzed the genetic relatedness of 30 commonly grown cultivars or varietal materials using amplified fragment length polymorphism (AFLP) markers with near-infrared fluorescence-labeled primers. Eight EcoRI + 3 bases/MseI + 3 bases primer set combinations were used in this investigation. Each selected primer set generated 113 to 158 scorable fragments. A total of 1102 AFLP fragments were detected, of which 778 were polymorphic (70.6%). An unweighted pair-group method of the arithmetic averages (UPGMA), principal coordinate analysis (PCOA), and bootstrap analysis were used to analyze the genetic relationships. The 30 cultivars were separated into five clusters. Cluster I contains 6 cultivars that are either from Senlan No.1 or Senlan No. 6 with Jaccardfs similarity coefficients ranging from 0.70 to 0.80. All of these 6 cultivars came from Taiwan, and were derived from somaclonal variants or sports. Just 3 cultivars were positioned in cluster II ranging from 0.71 to 0.76, and also originated from Taiwan. Cluster III included 13 cultivars, Jaccardfs similarity coefficients varied from 0.69 to 0.84. Seven cultivars from Senlan No. 15 or eSnowboy Romancef were situated in cluster IV with Jaccardfs similarity coefficients ranging from 0.69 to 0.82. Only eSantana Canaryf was positioned in cluster ‡X with Jaccardfs similarity coefficient at 0.62. This study established the genetic relationships of these commonly cultivated Spring Dendrobiums, and raised a concern over genetic vulnerability of cultivars in this study because of their close genetic similarities.Key words: Spring Dendrobium, amplified fragment length polymorphism (AFLP), genetic relationship, cultivars and varietal materials
Neuroprotective effects of Ellagic acid on Neonatal Hypoxic Brain Injury via Inhibition of Inflammatory Mediators and Down-regulation of JNK/p38 MAPK Activation
Purpose: To investigate if ellagic acid exerts neuroprotective effects in hypoxic ischemic (HI) brain injury by inhibiting apoptosis and inflammatory responses.Methods: Separate groups of rat pups from post-natal day 4 (D4) were administered with ellagic acid (10, 20 or 40 mg/kg body weight) orally till post- natal day 10 (D10). On D10, the rats were subjected to HI brain injury. Following HI injury, infarct size, weight and volume of the brain were measured. Apoptosis was assessed by Fluoro-Jade C staining. Expression of caspases (caspase-3, 8 and 9), apoptotic pathway proteins (Bax, Bad, Bcl-2 and Bcl-xL), MAPKs, NF κB(p65) and p-IK-Bα were assessed by western blotting. mRNA levels of inflammatory mediators (TNF-α, IL-1α, IL-1β, iNOS, COX-2) were analyzed.Results: Ellagic acidmarkedly (p < 0.05) reduced infarct size, volume and tissue loss. Significant (p < 0.05) reduction in neuroapoptosis was observed on pre treatment with ellagic acid. Expression levels of caspases, apoptotic pathway proteins and MAPK proteins were down-regulated with marked (p < 0.05) suppression of inflammatory mediators, NF-κB(p65) and p-IK-Bα.Conclusion: Ellagic acid affords neuroprotection in HI brain injury by inhibiting apoptosis, inflammatory responses and modulating the proteins of apoptotic and MAPK pathways. Thus, ellagic acid may be a potent candidate for the treatment of HI injury.Keywords: Brain injury, Ellagic acid, Hypoxia, Inflammatory mediators, Mitogen activated protein kinases, Neuroprotectiv
Convergent Analysis of Energy Conservative Algorithm for the Nonlinear Schrödinger Equation
Using average vector field method in time and Fourier pseudospectral method in space, we obtain an energy-preserving scheme for the nonlinear Schrödinger equation. We prove that the proposed method conserves the discrete global energy exactly. A deduction argument is used to prove that the numerical solution is convergent to the exact solution in discrete L2 norm. Some numerical results are reported to illustrate the efficiency of the numerical scheme in preserving the energy conservation law
Optimal control of a batch bioreactor for the production of a novel antifungal substance CF66I
More than 80% of the plant diseases are caused by fungi. Usually, fungi not only destroy the plants, but also produce mycotoxins that are harmful to human health. At present, chemical fungicides are mainlyused for the prevention of fungi-related plant diseases, however, research and development of biological prevention and controlling are of great importance. In this work, the effects of pH and temperature on cell growth and CF66I formation in batch culture of Burkholderia cepecia CF-66 werestudied. The pH value has a marked effect on cell growth and production of CF66I. The lag phase was much longer when pH set lower (e.g.5.0) or higher (e.g.8.0). For earlier phase, optimal pH value was 6.0, because the lag phase can be shortened and the whole fermentation phase can also be shorten and then quickly goes into CF66I production phase. In the late phase, the higher pH is in favor of the production of CF66I. Different temperature have different effect on cell yield, specific growth rate, CF66I yield and specific synthesis rate. In the prophase of fermentation, it is better to set higher temperature to make the cell growth maximizing as soon as possible. However in mid-anaphase, lower temperature shortens the fermentation time, reduce heating energy and the cost. According about results, an optimal control strategy was constructed
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