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971.
Optical windows with external surfaces shaped to satisfy operational environment needs are known as special windows. A novel special window, a sphere-cone-polynomial (SCP) window, is proposed. The formulas of this window shape are given. An SCP MgF2 window with a fineness ratio of 1.33 is designed as an example. The field-of-regard (FOR) angle is ±75°. From the window system simulation results obtained with the calculated fluid dynamics (CFD) and optical design software, we find that compared to the conventional window forms, the SCP shape can not only introduce relatively less drag in the airflow, but also have the minimal effect on imaging. So the SCP window optical system can achieve a high image quality across a super wide FOR without adding extra aberration correctors. The tolerance analysis results show that the optical performance can be maintained with a reasonable fabricating tolerance to manufacturing errors.  相似文献   
972.
Oligomeric and fibrillar amyloid-β (Aβ) are principally internalized via receptor-mediated endocytosis (RME) by microglia, the main scavenger of Aβ in the brain. Nevertheless, the inflammatory cascade will be evoked after vast Aβ aggregate binding to pattern recognition receptors on the cell membrane, which then significantly decreases the expression of these receptors and further deteriorate Aβ deposition. This vicious circle will weaken the ability of microglia for Aβ elimination. Herein, a combination of metabolic glycoengineering and self-triggered click chemistry is utilized to engineer microglial membranes with ThS as artificial Aβ receptors to promote microglia to phagocytose Aβ aggregates. Additionally, to circumvent the undesirable immune response during the process of the bioorthogonal chemistry reaction and Aβ-microglial interaction, Mn-porphyrin metal–organic frameworks (Mn-MOFs) with superoxide dismutase (SOD) and catalase (CAT) mimic activity are employed to carry N-azidoacetylmannosamine (AcManNAz) and eradicate over-expressed reactive oxygen species (ROSs). The artificial Aβ receptors independent of a signal pathway involved in immunomodulation as well as Mn-MOFs with antioxidant properties can synergistically promote the phagocytosis and clearance of Aβ with significantly enhanced activity and negligible adverse effects. The present study will not only provide valuable insight into the rational design of the microglial surface engineering strategy via bioorthogonal chemistry, but also hold great potential for other disease intervention associated with receptor starvation.

A combination of metabolic glycoengineering and self-triggered click chemistry is utilized to engineer a microglial membrane with ThS as artificial Aβ receptors to promote microglia to phagocytose Aβ aggregates.  相似文献   
973.
974.
Acta Mathematicae Applicatae Sinica, English Series - Let G = (V,E) be a graph and ϕ: V ∪E → {1, 2, · · ·, k} be a total-k-coloring of G. Let f(v)(S(v)) denote the...  相似文献   
975.
The effect of chlorination and ozone pre-oxidation on the photobacteria acute toxicity for dissolved organic matter (DOM) from sewage treatment plants was investigated in this study. The results show that ozone pre-oxidation enhanced the photobacteria acute toxicity of the water samples. DOM before and after ozone pre-oxidation was fractionated by resins into six kinds of hydrophobic and hydrophilic organics. The six fractions were chlorinated individually and the photobacteria acute toxicity before and after chlorination was tested. It was found that the percentage of hydrophilic organics in DOM significantly increased after ozone pre-oxidation and hydrophilic organics exhibited remarkably higher acute toxicity than hydrophobic organics. In view of potentiometric titration and fourier transform infrared (FTIR) analysis, the hydrophilic organics showed a rather higher content of ph-OH structures than hydrophobic organics.  相似文献   
976.

Calculating the time lags over different timescales using the cross-correlation technique may lead to a biased estimate of small timescales. Given a timescale for lightcurve binning, we propose to subtract the local average instead of the global average during the cross-correlation, in order to filter variations on timescales larger than the bin size. The new method allows us to make an unbiased estimate of the time lags using RXTE/PCA data on timescales as small as ∼5 ms, where the Fourier technique becomes invalid. We calculate the time lag spectra of Cygnus X-1 at different spectral states with the new method, and find that the source appears to have similar X-ray lags on small timescales independent of its spectral states.

  相似文献   
977.
Using a time-resolved optical interferometric technique, we investigate the ultrafast primary events following the interaction of an ultrashort laser pulse with pure water in the TW/cm2 regime. Because our method is sensitive to the quasi-instantaneous electron energy level position, we demonstrate that in contrast to the well-known low-intensity regime, where the free electrons are instantaneously captured by preexisting traps, in this new regime of excitation, free electrons are clearly observed, exhibiting a substantial contribution in the near IR. The delayed localization is attributed to the saturation of pre-existing cavities in the liquid by the large number of the excited electron states created.  相似文献   
978.
<正>We introduce a novel network-coding scheme that can be implemented in all-optical multicast networks.A simple and successful module based on the all-optical XOR gate is designed to realize the network coding scheme.The module is a key hardware component in realizing the proposed scheme.The working principle and the experimental results of the module are also presented.Experimental results show that the function of the module is sufficient in satisfying the requirements of the proposed network coding scheme.  相似文献   
979.
本文研究了用光漂白方法制备PMMA/DR1聚合物光棱镜的方法,测量了这种波导棱镜对1.064μm光的TE模和TM模在波导内传播光束的方向改变,并从理论上对测量结果进行了分析。  相似文献   
980.
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