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A fundamental feature of micro objects is the wave-particle duality which is addressed by Bohr's complementarity principle. To observe the wave and particle behaviours, quantum delayed-choice experiments based on linear optics have been realized at the single-photon level. Since they were performed by using a single photon as the input, repeating measurements were required in order to obtain different experimental data and adjusting experimental parameters was necessary prior to each of measurements. Different from the previous works, we here realize a simulation of quantum delayed-choice experiment through a single shot, which employs a classical intense light beam as the input instead of a single photon. Experimentally, we demonstrate the trade-off between distinguishability and visibility of photons in a two-arm interferometer in an intuitive way by utilizing the finite beam profile of the light. We observe the morphing between wave and particle natures of photons via a single shot of a charged-coupled-device camera. Since the image is captured within the exposure time which is several milliseconds, the phase fluctuation is negligible, and therefore our experimental setup is robust against the noise. This work provides a simple and new route to inspect quantum duality, which does not require adjusting experimental parameters frequently and only needs performing measurement once.
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Chitinase can degrade chitin and play an essential role in animal immunity and plant defense. The immune functions of Chitinase in Procambarus clarkii (P. clarkii) remain to elucidate. Here, we identified PcChitinase 2 gene sequence from P. clarkii and studied its spatial and temporal expression profiles. The PcChitinase 2 transcribed unequally in different tissues; however, its expression was highest in those of stomach, gut, and hepatopancreas. The challenge with lipolysaccharide or peptidoglycan significantly up-regulated the expression of PcChitinase 2 in hepatopancreas. The knockdown of the PcChitinase 2 gene by double-stranded RNA suppressed most of the Toll-pathway-related immune genes (phospholipase, lectin, sptazle Cactus, serine proteikinase, anti-lipopolysaccharide factor, and Toll) production were significantly increased. Our results suggest PcChitinase 2 may be involved in the innate immune responses of P. clarkii by modulating the toll pathway.
Assuntos
Astacoidea/imunologia , Quitinases/genética , Quitinases/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Receptores Toll-Like/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Astacoidea/enzimologia , Astacoidea/genética , Sequência de Bases , Quitinases/química , Perfilação da Expressão Gênica , Filogenia , Alinhamento de SequênciaRESUMO
We note that most of the studies of the single photon scattering inside a one-dimensional coupled resonator waveguide are based on the waveguide coupling with the atom systems. In this paper, we will study the single photon scattering enabled by another system, i.e., the second-order nonlinearity, which can act as a single photon switch to control the single photon transmission and reflection inside the one-dimensional coupled resonator waveguide. The transmission rate is calculated to analyze the single-photon scattering properties. In addition, a more complicated second-order nonlinear form, i.e., three-wave mixing, is discussed to control single photon transmission inside the one-dimensional coupled resonator waveguide.
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Background: Sedation and analgesia use in percutaneous radiofrequency ablation (RFPA) for liver cancer is a necessary part of the procedure; however, the optimal medicine for sedation and analgesia for PRFA remains controversial. The aim of this study was to compare the perioperative pain management, haemodynamic stability and side effects between oxycodone (OXY) and fentanyl (FEN) use in patients under dexmedetomidine sedation. Methods: Two hundred and five adults with an American Society of Anaesthesiologists physical status score of I to II were included in this study. Patients were assigned to the OXY (n=101) or FEN (n=104) group. Radiofrequency ablation was performed under spontaneous breathing and with painless anaesthesia administered intravenously. The outcomes included fluctuations in mean arterial pressure, heart rate, side effects and the perioperative numerical rating scale (NRS). Results: Radiofrequency ablation was successfully performed in 205 patients. No significant differences were observed in mean blood pressure fluctuations between the two groups despite the longer durations of ablation and total sedation time in the OXY group. The highest NRS score during the surgery and 1 hour and 2 hours after the surgery were significantly lower in the OXY group than in the FEN group. Heart rate fluctuations were significantly lower in the OXY group than in FEN group throughout the surgery. More patients in the FEN group displayed unwanted body movement and respiratory depression. Conclusions: Both oxycodone and fentanyl can be applied for liver cancer percutaneous radiofrequency ablation; however, oxycodone provides a better patient experience, lower postoperative pain, less respiratory depression and stable haemodynamic fluctuations.
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Analgesia/métodos , Analgésicos Opioides/administração & dosagem , Sedação Consciente/métodos , Neoplasias Hepáticas/cirurgia , Ablação por Radiofrequência/efeitos adversos , Idoso , Analgesia/efeitos adversos , Analgésicos Opioides/efeitos adversos , Pressão Sanguínea/efeitos dos fármacos , Determinação da Pressão Arterial , Sedação Consciente/efeitos adversos , Dexmedetomidina/administração & dosagem , Dexmedetomidina/efeitos adversos , Feminino , Fentanila/administração & dosagem , Fentanila/efeitos adversos , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Oxicodona/administração & dosagem , Oxicodona/efeitos adversos , Medição da Dor/estatística & dados numéricos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/psicologia , Dor Processual/diagnóstico , Dor Processual/etiologia , Dor Processual/prevenção & controle , Dor Processual/psicologia , Ablação por Radiofrequência/psicologia , Respiração/efeitos dos fármacos , Resultado do TratamentoRESUMO
We propose a method to improve the stimulated Raman adiabatic passage (STIRAP) via dissipative quantum dynamics, taking into account the dephasing effects. Fast and robust population transfer can be obtained with the scheme by the designed pulses and detuning, even though the initial state of the system is imperfect. With a concrete three-level system as an example, the influences of the imperfect initial state, variations in the control parameters, and various dissipation effects are discussed in detail. The numerical simulation shows that the scheme is insensitive to moderate fluctuations of experimental parameters and the relatively large dissipation effects of the excited state. Furthermore, the dominant dissipative factors, namely, the dephasing effects of the ground states and the imperfect initial state are no longer undesirable, in fact, they are the important resources to the scheme. Therefore, the scheme could provide more choices for the realization of the complete population transfer in the strong dissipative fields where the standard stimulated Raman adiabatic passage or shortcut schemes are invalid.
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BACKGROUND Whether regional anesthesia is associated with tumor-free and long-term survival is controversial. Here, we focused on whether epidural anesthesia affects the long-term survival of gastric cancer patients after surgery. MATERIAL AND METHODS We obtained the records of 273 patients undergoing gastric cancer surgery between August 2006 and December 2010. All patients received elective surgery, and the end-point was death. The general anesthesia group comprised 116 patients and the epidural-supplemented group comprised 157 patients. The results were analyzed using a multivariable model to determine the relationship between epidural use and long-term survival. RESULTS No obvious association was detected between epidural use and long-term survival according to the Cox model (P=0.522); the adjusted estimated hazard ratio was 0.919 (95% CI 0.71-1.19). However, according to Kaplan-Meier analysis, epidural anesthesia was associated with long-term survival among younger patients (age up to 64) (p=0.042, log-rank) (but not among older patients (p=0.203, log-rank). A lower American Society of Anesthesiologists (ASA) class and less chemoradiotherapy exposure were also associated with a longer survival. However, advanced tumor stage still has a significant negative impact on survival. CONCLUSIONS No obvious difference was detected between the 2 anesthesia groups, but younger patients may benefit from epidural anesthesia.
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Anestesia Epidural/métodos , Anestesia Geral/métodos , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Idoso , Anestesia Epidural/estatística & dados numéricos , Anestesia Geral/estatística & dados numéricos , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Sobreviventes , Resultado do TratamentoRESUMO
We propose an adiabatic passage approach to generate two atoms three-dimensional entanglement with the help of quantum Zeno dynamics in a time-dependent interacting field. The atoms are trapped in two spatially separated cavities connected by a fiber, so that the individual addressing is needless. Because the scheme is based on the resonant interaction, the time required to generate entanglement is greatly shortened. Since the fields remain in vacuum state and all the atoms are in the ground states, the losses due to the excitation of photons and the spontaneous transition of atoms are suppressed efficiently compared with the dispersive protocols. Numerical simulation results show that the scheme is robust against the decoherences caused by the cavity decay and atomic spontaneous emission. Additionally, the scheme can be generalized to generate N-atom three-dimensional entanglement and high-dimensional entanglement for two spatially separated atoms.
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Euphorbia species are widely distributed plants, many of which are used in folk medicine. Over the past twenty years, they have received considerable phytochemical and biological attention. Their diterpenoid constituents, especially those with abietane, tigliane, ingenane skeletons, are thought to be the main toxicant and bioactive factors. In this work, the utility of (13)C-NMR spectroscopy for the structural elucidation of these compounds is briefly discussed.
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Diterpenos/química , Euphorbia/química , Espectroscopia de Ressonância Magnética/métodos , Extratos Vegetais/química , Abietanos/química , Abietanos/isolamento & purificação , Isótopos de Carbono/química , Diterpenos/isolamento & purificação , Estrutura Molecular , Extratos Vegetais/isolamento & purificaçãoRESUMO
In this paper, we present a protocol to generate a W state of three superconducting qubits (SQs) by using multiple Schrödinger dynamics. The three SQs are respective embedded in three different coplanar waveguide resonators (CPWRs), which are coupled to a superconducting coupler (SCC) qubit at the center of the setups. With the multiple Schrödinger dynamics, we build a shortcuts to adiabaticity (STA), which greatly accelerates the evolution of the system. The Rabi frequencies of the laser pulses being designed can be expressed by the superpositions of Gaussian functions via the curves fitting, so that they can be realized easily in experiments. What is more, numerical simulation result shows that the protocol is robust against control parameters variations and decoherence mechanisms, such as the dissipations from the CPWRs and the energy relaxation. In addition, the influences of the dephasing are also resisted on account of the accelerating for the dynamics. Thus, the performance of the protocol is much better than that with the conventional adiabatic passage techniques when the dephasing is taken into account. We hope the protocol could be implemented easily in experiments with current technology.
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A scheme for arbitrary quantum state engineering (QSE) in three-state systems is proposed. Firstly, starting from a set of complete orthogonal time-dependent basis with undetermined coefficients, a time-dependent Hamiltonian is derived via Counterdiabatic driving for the purpose of guiding the system to attain an arbitrary target state at a predefined time. Then, on request of the assumed target states, two single-mode driving protocols and a multi-mode driving protocol are proposed as examples to discuss the validity of the QSE scheme. The result of comparison between single-mode driving and multi-mode driving shows that multi-mode driving seems to have a wider rang of application prospect because it can drive the system to an arbitrary target state from an arbitrary initial state also at a predefined time even without the use of microwave fields for the transition between the two ground states. Moreover, for the purpose of discussion in the scheme's feasibility in practice, a polynomial ansatz as the simplest exampleis used to fix the pulses. The result shows that the pulses designed to implement the protocols are not hard to be realized in practice. At the end, QSE in higher-dimensional systems is also discussed in brief as a generalization example of the scheme.
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We propose an effective and flexible scheme for reverse engineering of a Hamiltonian by designing the evolution operators to eliminate the terms of Hamiltonian which are hard to be realized in practice. Different from transitionless quantum driving (TQD), the present scheme is focus on only one or parts of moving states in a D-dimension (D ≥ 3) system. The numerical simulation shows that the present scheme not only contains the results of TQD, but also has more free parameters, which make this scheme more flexible. An example is given by using this scheme to realize the population transfer for a Rydberg atom. The influences of various decoherence processes are discussed by numerical simulation and the result shows that the scheme is fast and robust against the decoherence and operational imperfection. Therefore, this scheme may be used to construct a Hamiltonian which can be realized in experiments.
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A rapid and simple method was established for the simultaneous determination of ten diterpenes by reversed phase HPLC coupled with evaporative light scattering detection. Chromatographic separation was carried out in gradient mode by using a WondaSil™ C(18) column (250mm×4.6mm, 5µm) with mobile phases of methanol and water at 1mL/min. The drift tube temperature of evaporative light scattering detector was set to 65°C and nitrogen flow-rate was 2.7L/min. The method validated was shown to be specific, precise, accurate and linear. Moreover, it was applied to investigate four samples of E. fischeriana with different extracting methods. Contrast to the dried roots, the fresh roots had much higher content of prostratin which represented much higher inflammatory effects than other diterpenes. The results demonstrated that the dried roots were suitable for the ordinary therapy to avoid intense stimulatory, while the fresh roots could be used in the anticancer treatment. All of the results suggested that comparative analysis of chemical components as biomarker and connecting toxic effects of an herb was helpful for revealing the mechanism of its toxicity, and for guiding safer and better application of the herb in TCM clinic.