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We propose advanced image enhancement algorithms for conventional ghost imaging. The algorithms are based on modulating the bucket signals to enlarge their divergence. In this paper, we adopt three mathematical functions: power function like f ( B ) = B n , exponential function like f ( B ) = exp ( p ⋅ B ) , and self modulation function like f ( B ) = B q ⋅ B , where B is the bucket intensity in the object path. Our experimental results demonstrate the enhancement of the contrast of the correlated images with these algorithms.

We present two schemes of Lau effect for an object, an electromagnetically induced grating generated based on the electromagnetically induced effect. The Lau interference pattern is detected either directly in the way of the traditional Lau effect measurement with a classical thermal light being the imaging light, or indirectly and nonlocally in the way of two-photon coincidence measurement with a pair of entangled photons being the imaging light.

We report a displacement measurement experiment in second-order correlation and subwavelength correlation with thermal light. Our target is a single slit, which is inserted into a Sagnac interferometer to mimic a double-slit apparatus. According to the correlated diffraction pattern, we can predict the excursion of the slit from the optical axis. When the slit is shifted, we can predict the displacement accurately. We also present the mathematical presentations of beam propagation and reflection in comprehensive deduction.

We present theoretical analysis and experimental demonstration of near field and far field spatial correlations of thermal light. Similar to the inequality Δ x − Δ p + 1 for a two-photon entangled source, we obtain an inequality Δ x − Δ p − 1 which also concerns both photon position and transverse wavevector correlations of thermal light. To test this inequality, we carry out an experiment in which ghost diffraction and ghost imaging can be simultaneously observed without the aid of any lenses. Meanwhile, the inequality is examined experimentally.

Lau effect is a self-imaging formed in the far field of a pair of gratings illuminated by spatially incoherent light. We report the experimental demonstration of the second-order Lau effect with incoherently pseudo-thermal light. Spatially periodic structures were nonlocally superposed giving rise to interference patterns in intensity correlation measurement. The experimental results are in agreement with the theoretical analysis. The second-order Lau effect can be well understood by the unfolded version of the experimental setup where the bucket detection can be thought as the incoherent illumination in classical Lau effect.

Gastrodin (GAS), the main bioactive component of G. elata Blume, has important pharmaceutical and functional activities. The aim of this study is to produce GAS from p-2-hydroxybenzyl alcohol (HBA) through biotransformation. The conversion of exogenous HBA into GAS compound was conducted using cell suspension cultures of Armillaria luteo-virens Sacc. The bioconversion conditions were fully optimized with response surface methodology (RSM), turning out that the optimal transformation conditions composed of 3 mg/mL HBA, 6.5 g/30 mL inoculums level, 1.5% Tween 80, pH 4.5, and transformation temperature at 23°C. Under the optimized conditions, the conversion productivity of GAS reached the highest value (5.65 ± 0.45 mg/L). Verified experiments further validated that the optimized conditions were suitable for predicting the actual process of HBA transformation in the resting-cell system. The bioconversion kinetics model was as well simulated with Michaelis–Menten equation, which showing the suitability. The present study proposed the biotransformation pathway of HBA into GAS by resting cells transformation, indicating that the biotransformation process involved glucosylation reaction. Furthermore, Imprinting Control Region (ICR) mice in vivo demonstrated that the identified gastrodin possessed a significant anti-inflammatory activity. The fundamental data in the present work provides an efficient way to produce GAS through the whole-cells biocatalysis.

This work aimed to develop the submerged cultivation conditions for improved exopolysaccharides (EPS) production by Armillaria luteo-virens Sacc. The effects of culture temperature, aeration rate, inoculum level, initial pH, and additives on EPS formation and mycelial growth are investigated. The aeration rate, initial pH, and inoculum level significantly affected EPS production under the submerged cultivation. The developed conditions were as follows: cultivation temperature 23 °C, initial pH 5.0, aeration rate 0.5 vvm, 0.5% Tween 80, inoculum level 5% (v/v), and shaking speed 120 r/min. Under the developed conditions, the highest EPS production was 13.01 g/L at 5 days culture time. EPS production was examined in a 5 L bioreactor, and an unstructured kinetic model for EPS formation was well developed. The verified investigations in the large-scale cultivation system showed that the developed models are able to predict the submerged cultivation process of EPS formation. Current results revealed that the submerged cultivation conditions can be utilized to control EPS production, and the unstructured models developed are suitable for explaining EPS production by A. luteo-virens Sacc QH in a large-scale cultivation bioreactor.

We report an experimental realization of lensless ghost imaging for a phase-only object with pseudo-thermal light, which was proposed by W. Gong and S. Han [Phys. Rev. A 82, 023828 (2010)]. In contrast with conventional ghost imaging, the scheme involves the interference of two correlated fields and the phase information of the object can be retrieved. This imaging technique completes the nonlocally lensless spatial reconstruction of both amplitude and phase distributions in ghost imaging with thermal light.

We report the experimental observation of quantum holographic imaging of one-dimensional object with entangled photon pairs, generated in a spontaneous parametric down-conversion process. The signal photons play both roles of “object wave” and “reference wave” in holography but are recorded by a point detector providing only encoding information, while the idler photons travel freely and are locally manipulated with spatial resolution. The holographic image is formed by the two-photon correlation measurement, although both the signal and idler beams are incoherent. Three types of quantum holography schemes are analyzed according to the detection regime of the signal photons.