An Activatable Lanthanide Luminescent Probe for Time‐Gated Detection of Nitroreductase in Live Bacteria

Herein we report the development of a turn‐on lanthanide luminescent probe for time‐gated detection of nitroreductases (NTRs) in live bacteria. The probe is activated through NTR‐induced formation of the sensitizing carbostyril antenna and resulting energy transfer to the lanthanide center. This novel NTR‐responsive trigger is virtually non‐fluorescent in its inactivated form and features a large signal increase upon activation. We show that the probe is capable of selectively sensing NTR in lysates as well as in live bacteria of the ESKAPE family which are clinically highly relevant multiresistant pathogens responsible for the majority of hospital infections. The results suggest that our probe could be used to develop diagnostic tools for bacterial infections.     

Experimental and Numerical Investigation on Effects of the Steam Ingestion on the Aerodynamic Stability of an Axial Compressor

In order to investigate the influence of steam ingestion on the aerodynamic stability of a two-stage low-speed axial-flow compressor, multiphase flow numerical simulation and experiment were carried out. The total pressure ratio and stall margin of the compressor was decreased under steam ingestion. When the compressor worked at 40% and 53% of the nominal speed, the stall margin decreased, respectively, by 1.5% and 6.3%. The ingested steam reduced the inlet Mach number and increased the thickness of the boundary layer on the suction surface of the blade. The low-speed region around the trailing edge of the blade was increased, and the flow separation region of the boundary layer on the suction surface of the blade was expanded; thus, the compressor was more likely to enter the stall state. The higher the rotational speed, the more significant the negative influence of steam ingestion on the compressor stall margin. The entropy and temperature of air were increased by steam. The heat transfer between steam and air was continuous in compressor passages. The entropy of the air in the later stage was higher than that in the first stage; consequently, the flow loss in the second stage was more serious. Under the combined action of steam ingestion and counter-rotating bulk swirl distortion, the compressor stability margin loss was more obvious. When the rotor speed was 40% and 53% of the nominal speed, the stall margin decreased by 6.3% and 12.64%, respectively.     

Quantum coherence of multiqubit states in correlated noisy channels

Quantum coherence captures the essential nature of a quantum system[1]and can serve as a resource for quantum information processing[2].Recent studies also provide evidence that long-lived quantum coherence is crucial for overcoming the classical limits of measurement accuracy in quantum metrology[3-5].However,in practice,the unavoidable interaction of a principal system with its surroundings results in decoherence in most situations.Consequently,the advantage of quantum coherence in empowering the performance of quantum tasks will disappear in a very short time interval,which remains one of the major obstacles in its potential application.     

An efficient stereoselective synthesis of aminocyclohexenes from 7-azanorbornenes via LiAlH4 mediated tandem double bond migration-ring opening sequence

hNav1.7 had received great interest in the past decade owing to its attractive mechanism of actions in pain processing pathway. More recently, we developed a series of efficacious hNav1.7 inhibitors for analgesic, which were characterized with a novel aminocyclohexene as pharmacophore. Herein, we reported our synthetic efforts to construct the unique scaffold, which can be rapidly accessed from readily available 7-azanorbornenes via an unexpected catalyst-free, LiAlH₄ mediated tandem double bond migration-ring opening sequence. A probable mechanism was proposed to illuminate the good regio- and stereoselectivity.     

Robust nonlinear control design for dynamic positioning of marine vessels with thruster system dynamics

Nonlinear Dynamics - Considering the dynamics characteristics of thruster systems for dynamically positioned marine vessels with model parameter uncertainties and unknown time-varying ocean...     

Marcinkiewicz Integrals with Non-Doubling Measures

Let μ be a positive Radon measure on which may be non doubling. The only condition that μ must satisfy is μ(B(x, r)) ≤ Cr ⁿ for all , r > 0 and some fixed constants C > 0 and n ∈ (0, d]. In this paper, we introduce the Marcinkiewicz integral related to a such measure with kernel satisfying some H?rmander-type condition, and assume that it is bounded on L ²(μ). We then establish its boundedness, respectively, from the Lebesgue space L ¹(μ) to the weak Lebesgue space L ^1,∞(μ), from the Hardy space H ¹(μ) to L ¹(μ) and from the Lebesgue space L ^∞(μ) to the space RBLO(μ). As a corollary, we obtain the boundedness of the Marcinkiewicz integral in the Lebesgue space L ^p (μ) with p ∈ (1,∞). Moreover, we establish the boundedness of the commutator generated by the RBMO(μ) function and the Marcinkiewicz integral with kernel satisfying certain slightly stronger H?rmander-type condition, respectively, from L ^p (μ) with p ∈ (1,∞) to itself, from the space L log L(μ) to L ^1,∞(μ) and from H ¹(μ) to L ^1,∞(μ). Some of the results are also new even for the classical Marcinkiewicz integral. The third (corresponding) author was supported by National Science Foundation for Distinguished Young Scholars (No. 10425106) and NCET (No. 04-0142) of China.     

Synthesis, Characterization, DNA-Binding and Antiproliferative Activity of Nd(III) Complexes With N-(Nitrogen Heterocyclic) Norcantharidin Acylamide Acid

Three novel complexes [Nd(L)(NO₃)(H₂O)₂]·NO₃·2H₂O (HL¹ = N-pyrimidine norcantharidin acylamide acid, C₁₂H₁₃N₃O₄; HL² = N-pyridine norcantharidin acylamide acid, C₁₃H₁₄N₂O₄; HL³ = N-phenyl norcantharidin acylamide acid, C₁₄H₁₅NO₄) were synthesized. HL¹, HL² and HL³ are the ligand of complex(1), complex(2) and complex(3), respectively. Their structures were characterized by elemental analysis, conductivity measurement, infrared spectra and thermogravimetric analysis. The DNA-binding properties of the complexes have been investigated by fluorescence spectroscopy and viscosity measurements. The results suggest that the complexes can bind to DNA by partial intercalation. The liner Stern-Volmer quenching constant K_sq values are 3.3(±0.21)(1), 1.7(±0.19)(2) and 0.9(±0.04)(3), respectively. Complex (1) and (2) have been found to cleave pBR322 plasmid DNA at physiological pH and temperature. The test of antiproliferation activity indicates that complex(1) has strong antiproliferative ability against the SMMC7721 (IC₅₀ = 131.7 ± 23.4 μmol·L⁻¹) and A549 (IC₅₀ = 128.4 ± 19.9 μmol·L⁻¹) cell lines. The inhibition rates of complex(2) (IC₅₀ = 86.3 ± 11.3 μmol·L⁻¹) are much higher than that of NCTD (IC₅₀ = 115.5 ± 9.5 μmol·L⁻¹) and HL² (111.0 ± 5.7 μmol·L⁻¹) against SMMC7721 cell lines.     

A note on the limiting weak-type behavior for maximal operators

We study the following open question raised by Janakiraman in (2006): for and , what is the limiting behavior of

as ? In this note, we give a complete answer to this question.

     

XeCl准分子激光能量提取研究

在高功率准分子激光系统建设中,希望能获得较短的脉冲宽度和尽量多的激光能量。实验研究了不同注入水平下,脉冲时间间隔对脉冲链放大波形和放大器提取效率的影响;基于四能级速率方程和准分子反应动力学建立了准分子激光放大模型,计算了多种注入方式下种子光的放大过程,对关键参数给出了量化描述,得到与实验相符的计算结果。研究结果显示:脉冲序列间隔为9.3 ns时,可获得约95%的连续注入情形下放大能量;对该准分子激光系统来讲,9.3 ns是比较合适的脉冲间隔。     

Modeling and analysis of an agent-based model for Chinese stock market

We constructed an agent-based stock market model which concisely describe investors? heterogeneity and adaptability by introducing price sensitivity and feedback time. Under different parameters, the peak and fat-tail property of return distribution is produced and the obtained statistic values coincide with empirical results: the center peak exponents range from ?0.787 to ?0.661, and the tail exponents range from ?4.29 to ?2.37. Besides, long-term correlation in volatility is examined by DFA1 method, and the obtained exponent α is 0.803, which also coincides with the exponent of 0.78 found in real market.