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Hemangioma, the most common benign vascular tumor, not only affects the appearance and psychology but also has a life-threatening potential. It is considered that clonal vascular endothelial cell proliferation and excessive angiogenesis are responsible for hemangioma pathogenesis, in which abnormal cytokines/pathways are closely implicated, primarily including high expression of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) as well as their downstream pathways, especially phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt). These further stimulate the migration and proliferation of vascular endothelial cells and promote the formation of new vessels, ultimately leading to the occurrence and development of hemangioma. Proanthocyanidins are naturally active substance from plants and fruits. They possess multiple functions like antiproliferation, antiangiogenesis, and antitumor. It has been demonstrated that proanthocyanidins effectively work in various diseases via inhibiting the expression of various factors, e.g., HIF-1α, VEGF, PI3K, and Akt. Considering the pathogenesis of hemangioma and the effect of proanthocyanidins, we hold a hypothesis that proanthocyanidins would be applied in hemangioma via downregulating cytokine/pathway expression, suppressing vascular cell proliferation and arrest abnormal angiogenesis. Taken together, proanthocyanidins may be a potential novel way for the treatment of hemangioma.

Macrophages, a kind of innate immune cells, derive from monocytes in circulation and play a crucial role in the innate and adaptive immunity. Under the stimulation of the signals from local microenvironment, macrophages generally tend to differentiate into two main functional phenotypes depending on their high plasticity and heterogeneity, namely, classically activated macrophage (M1) and alternatively activated macrophage (M2). This phenomenon is often called macrophage polarization. In pathological conditions, chronic persistent inflammation could induce an aberrant response of macrophage and cause a shift in their phenotypes. Moreover, this shift would result in the alteration of macrophage polarization in some vascular dermatoses; e.g., an increase in proinflammatory M1 emerges from Behcet’s disease (BD), psoriasis, and systemic lupus erythematosus (SLE), whereas an enhancement in anti-inflammatory M2 appears in infantile hemangioma (IH). Individual polarized phenotypes and their complicated cytokine networks may crucially mediate in the pathological processes of some vascular diseases (vascular dermatosis in particular) by activation of T cell subsets (such as Th1, Th2, Th17, and Treg cells), deterioration of oxidative stress damage, and induction of angiogenesis, but the specific mechanism remains ambiguous. Therefore, in this review, we discuss the possible role of macrophage polarization in the pathological processes of vascular skin diseases. In addition, it is proposed that regulation of macrophage polarization may become a potential strategy for controlling these disorders.

The photorefractive properties of nominally pure near-stoichiometric LiNbO3 crystals grown from congruent melts containing 11 mol % K2O are studied, and some photorefractive properties which are very different from those in congruent LiNbO3 crystals are observed. Large stationary energy transfer (Γmax=25 cm−1) exists in near-stoichiometric crystals though the photovoltaic field is dominant. The light-induced scattering fanning is markedly asymmetric in the crystals, which is very different from the symmetric fanning observed in congruent ones. Our analysis shows that these differences are caused by the large photovoltaic field and the relatively small density of filled traps in as-grown near-stoichiometric LiNbO3.

A set of strained-layer GexSi1-x/Si multiple quantum wells has been investigated by electroreflectance (ER) spectroscopy. In the ER spectra we have observed transitions in the quantum wells associated with the critical points E0, E1, as well as E'0. The transitions of E0 and E'0, which are very weak in the bulk material, are apperently enhanced in quantum wells.

Photoreflectance spectra of doped molecular-beam-epitaxy GaAs films grown on semi-insulating GaAs substrate, modulated by different pump beams, are studied. From the interference effect of two light beams reflected from different interfaces of a sample, the PR signals from the surface of the MBE film and that from the interface of film and substrate can be distinguished in the spectra. The behavior of the electric fields of the space charge region at the surface of GaAs and the interface of GaAs/SI-GaAs is also investigated.

Laser‐induced dark traces in doped LiNbO3 crystals are studied with the 1064 nm fundamental radiation and the 532 nm second harmonic radiation of the Nd:YAG laser operating in a pulse mode. The results show that the dark traces are induced only by the 532 nm radiation. The linear relationship between the transmission loss and the 532 nm power density indicates that dark traces are not due to two‐photon absorption. The recovery rates of the absorption in LiNbO3 with different wavelength probe laser are measured and show that laser‐induced dark traces accompany more than one defect appearing in LiNbO3, and disappear quicker at higher temperature.

A mutually pumped phase conjugator is realized using a bridge configuration with a novel crystal of copper-doped potassium sodium strontium barium niobate. Phase conjugation reflectivity reaches 218%. The buildup times of phase conjugation outputs are measured, and a curve fit of the times is made. A self-curving coupling channel is observed. We use the theory developed by Lyubomudrov and Shkunov to model the coupling channels. The curved beam trajectory depending on the incident position and the incident angle is also calculated. With the results we show that one, two, three, and more four-wave mixing interaction regions exist in photorefractive bridge mutually pumped phase conjugators. Additionally, the simultaneous phase conjugation outputs of four incident beams are also demonstrated experimentally with the crystal.

We show a double phase conjugator with novel crystals of copper-doped potassium sodium strontium barium niobate. The phase conjugation reflectivity can reach 278% and depends on relative input positions of both incident beams. The response time with the input beam power ratio is measured and modeled as a function of input beam power ratio. The formation of the arch coupling loop is analyzed with theoretical simulation results and a positive feedback process is proposed. The influence of a self-pumped phase conjugation process on double phase conjugation fidelity is also discussed. It is necessary to avoid generating self-pumped phase conjugation to prevent the reduction of double phase conjugation fidelity.