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Lithium niobate (LN) crystal with anti‐reflective subwavelength structures (ASSs) has great applications in high‐power tunable optical parametric oscillator (OPO) lasers. However, it is still a great challenge to 3D nanofabrication of LN ASSs. Herein, a wet‐etching‐assisted laser polarization domain inversion (WE‐LPDI) technology is proposed to fabricate periodic cone arrays with a period from 200 nm to 4 µm on LN. Based on the optimized structural parameters, large‐area LN ASSs with a period of 1.3 µm and a height of 1.7 µm were fabricated on LN, which exhibits an average transmittance of 3–5 µm increasing from 78% to 85% and a highest transmittance of 88% at 5 µm. It has been demonstrated that the LN ASSs show high stability under high‐temperature and high‐power laser irradiation, which shows potential applications for high‐power mid‐IR lasers. The results indicate that the WE‐LPDI technology provides a novel way for 3D nanofabrication of LN. [ABSTRACT FROM AUTHOR]

• Advances in femtosecond laser with etching fabrication of micro-optical components are reviewed. • Wet and dry etching processes for various hard materials are described. • Cutting-edge applications of femtosecond laser with etching are introduced. • Current challenges and future perspective of this field have been discussed. With advantages of small size, light weight, flexible design, and easy mass production, micro-optical components of hard materials have a wide range of potential applications in artificial intelligence, information processing, aerospace, biomedicine, laser technology, etc. However, it is difficult to realize three-dimensional (3D) micro-optical components with complex morphologies. In recent years, femtosecond laser with etching technology has proven to be effective for the fabrication of micro-optical components in hard materials owing to their high precision, high surface quality, and ability to fabricate arbitrary 3D structures. This review focuses on the recent advancements in femtosecond laser with etching fabrication of micro-optical components of various materials. We briefly introduce femtosecond laser modification and summarize the wet and dry etching processes of various materials. According to the types of optical components, the methods and applications of optical components fabricated by femtosecond laser with etching are discussed. The paper concludes with a follow-up and an outlook of femtosecond laser processing in femtosecond laser with etching fabrication of micro-optical components. [ABSTRACT FROM AUTHOR]

The transverse static load, resultant from self-weight, significantly impacts both the response and the nonlinear dynamic behavior of a flexible inclined cantilever with a large lumping tip mass under harmonic base motion. However, the transverse static load was not taken into account and the mode shape of a pure cantilever beam was directly adopted during Galerkin’s procedure in the formulations of a cantilever carrying a large lumping tip mass in many previous studies. In this paper, (1) the static load effect caused by the self-weight in an inclined cantilever is considered by using a coordinate transformation, (2) the efficacy of adopting a pure cantilever beam mode shape to analyze a cantilever beam carrying a large lumping mass is studied and (3) a recently proposed semi-analytical method named parameter-splitting multiple-scales method is extended to analyze the cantilever studied to examine its effectiveness. First, the extended Hamilton’s principle is utilized to formulate the equation of motion of the cantilever studied. After that, the mode shape of a pure cantilever and the exact mode shape of a cantilever carrying a lumping mass are separately adopted in Galerkin’s method to transform the partial differential equation into ordinary differential equations. The frequency-response curves of the discretized nonlinear differential equations obtained by the numerical continuation method and the parameter-splitting multiple-scales method are compared to address ① the transverse static load effect on the frequency-response and nonlinear dynamical behavior of the beam, ② the discrepancies between the resultant frequency-response curves obtained by using two different mode shapes and ③ the efficacy of the parameter-splitting multiple-scales method on solving strongly nonlinear practical problem. [ABSTRACT FROM AUTHOR]

Rosa roxburghii Tratt residue is rich in dietary fiber and a variety of active substances, but its dietary fiber is mainly insoluble dietary fiber, and the content of soluble dietary fiber (SDF) is low. To make full use of R. roxburghii Tratt residue, steam explosion (SE) pretreatment was used to treat the residue to determine its effect on the extraction yield of SDF and the functionality of dietary fiber (DF). Response surface methodology was used to determine the conditions of SE for optimizing the SDF extraction yield in the residue. When R. roxburghii Tratt residue was pretreated by SE at 60 mesh for 97 s, combined with 0.87 MPa, the content of SDF was increased from 9.31 ± 0.07% to 15.82 ± 0.31% in comparison with the control and DF extracted by SE showed the high cholesterol adsorption, glucose adsorption, cation exchange, nitrite adsorption, and hydroxyl radicals inhibition. Practical applications: Due to the rough texture and poor taste, the high content of DF in the Rosa roxburghii Tratt residue is often discarded during the processing of freshly squeezed juice. SE can significantly improve the utilization of DF, which is a more economical modification method. This work provides a theoretical basis for the R. roxburghii Tratt by‐product as a new source of high‐quality dietary fiber. [ABSTRACT FROM AUTHOR]

• A method of phycocyanin glycation promoted by ultra-high pressure was explored. • Phycocyanin can fully conjugate with dextran 20,000 in composite modification. • Some functions of CM-PC (composite modified phycocyanin) were enhanced. • Functional properties of CM-PC improved after hydroxyl groups being introduced. Phycocyanin (PC), a plant-based protein with interesting biological activity, is rarely directly applied in the food industry because it has structural and functional limitations. This study combined ultra-high-pressure (UHP) treatment with glycation to improve PC functionality and explored resulting structural changes using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, scanning electron microscopy, Fourier-transform infrared spectroscopy, circular dichroism, and UV–visible spectroscopy. The UHP treatment obviously improved the speed and degree of glycation and the composite-modified PC (CM-PC) showed high solubility and good emulsifying and foaming performance. Scanning electron microscopy images showed the CM-PC surface was loose and fluffy. Gel electrophoresis, Fourier-transform infrared spectroscopy, and circular dichroism results demonstrated that the content of α-helix decreased from 78.1% in PC to 26.6% in CM-PC, and hydroxyl groups were introduced. UV–visible spectroscopy showed that the mechanism of composite modification involved stretching of the PC and promotion of binding with sugars. [ABSTRACT FROM AUTHOR]

A C-band high efficiency and high gain two-stage power amplifier based on AlGaN/GaN high electron mobility transistor (HEMT) is designed and measured in this paper. The input and output impedances for the optimum power-added efficiency (PAE) are determined at the fundamental and 2nd harmonic frequency (f0 and 2f0). The harmonic manipulation networks are designed both in the driver stage and the power stage which manipulate the second harmonic to a very low level within the operating frequency band. Then the inter-stage matching network and the output power combining network are calculated to achieve a low insertion loss. So the PAE and the power gain is greatly improved. In an operation frequency range of 5.4 GHz–5.8 GHz in CW mode, the amplifier delivers a maximum output power of 18.62 W, with a PAE of 55.15% and an associated power gain of 28.7 dB, which is an outstanding performance. [ABSTRACT FROM AUTHOR]

The shape memory effect is the capability of a structure or a material that can be deformed into a certain temporary shape under external stimulus, and the shape will be fixed without the stimulus. The recovery process can be triggered by the same stimulus. The intelligent tunable device based on the shape memory effect has a wide range of applications in many fields. In the optical field, smart diffraction gratings can accomplish in situ optical diffractions according to requirements, meeting the high demand in the next generation of smart optical systems. However, it is essential to construct high‐precision grating structures based on shape memory materials. Here, a smart diffraction grating based on UV‐curable shape memory polymers (SMPs) via two‐beam interference is reported, with nano‐scale precision, excellent deformability and recovery ability, and adjustable spectroscopic performance. More importantly, based on the shape memory effect, grating structures that surpass the precision of the fabrication system can be obtained. The smart grating exhibits rapid deformation and recovery upon heating and long‐term storage capability, which facilitates them to be applied in optics, electronics, and integrated sensing. [ABSTRACT FROM AUTHOR]

Purpose: Clinical studies found that regular aerobic exercise has analgesic and antianxiety effects; however, the underlying neural mechanisms remain unclear. Multiple studies have suggested that regular aerobic exercise may exert brain-protective effects by promoting the release of serotonin, which may be a pain modulator. Anterior cingulate cortex (ACC) is a key brain area for pain information processing, receiving dense serotonergic innervation. As a result, we hypothesized that exercise may increase the release of serotonin in the ACC, thus improving pain and anxiety behaviors. Methods: Integrative methods were used, including behavioral, electrophysiological, pharmacological, biochemical, and genetic approaches, to explore the effects of regular aerobic exercise and the underlying neural mechanisms. Results: Regular aerobic exercise in the form of voluntary wheel running for 30 min daily for 15 d showed significant effectiveness in relieving pain and concomitant anxiety in complete Freund's adjuvant–induced chronic inflammation pain models. c-Fos staining and multielectrode array recordings revealed alterations in neuronal activities and synaptic plasticity in the ACC. Moreover, systemic pharmacological treatment with 4-chloro- dl -phenylalanine (PCPA) to deplete endogenous serotonin and local delivery of serotonin to the ACC revealed that exercise-related serotonin release in the ACC bidirectionally modulates pain sensitization and anxiety behaviors by modulating synaptic plasticity in the ACC. Furthermore, we found that 5-HT1A and 5-HT7 receptors mediated the serotonin modulation effects under conditions of regular aerobic exercise through local infusion of a selective antagonist and shRNA in the ACC. Conclusions: Our results reveal that regular aerobic exercise can increase serotonin release and modulate synaptic plasticity in the ACC, ultimately improving pain and concomitant anxiety behaviors through the functions of the 5-HT1A and 5-HT7 receptors. [ABSTRACT FROM AUTHOR]

Periodic nanostructures have wide applications in micro-optics, bionics, and optoelectronics. Here, a laser interference with subsequent etching technology is proposed to fabricate uniform periodic nanostructures with controllable morphologies and smooth surfaces on hard materials. One-dimensional microgratings with controllable periods (1, 2, and 3 μm) and heights, from dozens to hundreds of nanometers, and high surface smoothness are realized on GaAs by the method. The surface roughness of the periodic microstructures is significantly reduced from 120 nm to 40 nm with a subsequent inductively coupled plasma (ICP) etching. By using laser interference with angle-multiplexed exposures, two-dimensional square- and hexagonal-patterned microstructures are realized on the surface of GaAs. Compared with samples without etching, the diffraction efficiency can be significantly enhanced for samples with dry etching, due to the improvement of surface quality. [ABSTRACT FROM AUTHOR]

The present study investigated the molecular mechanism of apoptosis and autophagy in prostate epithelial cells under androgen deprivation (AD). BPH‑1 cells were divided into four groups as follows: Control (Cont), AD, autophagy inhibition (AI) and AD + AI groups. Cells in the four groups were treated accordingly, and the level of apoptosis was subsequently measured via flow cytometry. The expression of the microtubule‑associated proteins 1A/1B light chain 3 (LC3), caspase‑3, poly (ADP‑ribose) polymerase 1 (PARP‑1) and Beclin‑1 proteins of BPH‑1 cells was detected at different time points following culture in androgen‑deprived medium. Western blotting revealed that the basal levels of the LC3‑II protein were detected at 0 h. At 4 h, LC3‑II was significantly increased compared with 0 h (P<0.05). Beginning at 20 h, the expression level of the LC3‑II protein decreased significantly (P<0.05). Western blotting revealed that beginning at 24 h, the expression level of the PARP‑1 protein decreased significantly (P<0.001) and the cleavage fragments of the PARP‑1 protein appeared. These results further imply that autophagy serves a cell protective function by mutual inhibition with apoptosis in BPH‑1 cells in the removal of androgen conditions. Furthermore, the fragments of the cleaved Beclin‑1 protein appeared as 35 and 37 kDa bands. Flow cytometry analysis demonstrated that the rate of cell apoptosis in the AD, AI and AD + AI groups was significantly increased compared with the Cont group (P<0.01). Compared with the AD or the AI groups individually, the rate of cell apoptosis in the AD + AI group was significantly increased (P<0.001). These findings suggest that in the early stage of AD, autophagy has a compensatory function in the cell, whereas in the whole process, autophagy and apoptosis share a mutual antagonism. The Beclin‑1‑C protein fragment contributed positive feedback to the process of apoptosis, which may be a potential mechanism of AD therapy. Therefore, AD and AI exhibit a synergistic effect to further improve the level of apoptosis. [ABSTRACT FROM AUTHOR]

Eriodictyol, a flavonoid present in citrus fruits, has been reported to have antioxidant and anti-inflammatory effects. In this study, the protective effects of eriodictyol on cisplatin (CP)-induced kidney injury were detected. CP-induced kidney injury model was established by administration of CP (20 mg/kg). The results showed that treatment of eriodictyol inhibited the production of blood urea nitrogen (BUN), creatinine, MDA, TBARS, reactive oxygen species (ROS), as well as the production of TNF-α, and IL-1β in kidney tissues induced by CP. Eriodictyol also up-regulated the activities of SOD, CAT, and GSH-PX decreased by CP. Furthermore, eriodictyol was found to up-regulate the expression of Nrf2/HO-1 and inhibited CP-induced NF-κB activation in kidney tissues. In conclusion, eriodictyol protected against CP-induced kidney injury through activating Nrf2 and inhibiting NF-κB activation. [ABSTRACT FROM AUTHOR]

In this paper, we carried out an analysis of the breakdown characterization method by the investigation on off-state leakage currents and breakdown curves. For conventional breakdown, seven kinds of breakdown curves are summarized and it is found that only two of them can be shown by the conventional three-terminal breakdown characterization method reasonably. For the other five kinds of breakdown curves, the value of the gate leakage current is larger than that of the drain leakage current for a certain drain-bias range. Besides, the source leakage current cannot represent the buffer leakage current, and the values and signs of them are different. These problems contradict the conventional characterization method, indicating that the conventional method should be modified to characterize the breakdown mechanisms correctly. The similar problems also exist for time-dependent breakdown. The buffer and drain-gate leakage currents were obtained by a simple method and the conventional breakdown characterization method was modified by using these two currents. The problems in the conventional breakdown characterization method are solved by using the modified method. Experiments indicate that the modified breakdown characterization method is crucial to investigate the breakdown mechanisms, especially when source-gate leakage current cannot be neglected compared with the buffer leakage current. [ABSTRACT FROM AUTHOR]

To enhance therapeutic efficacy and reduce adverse effects, ancient practitioners of traditional Chinese medicine (TCM) prescribe combinations of plant species/animal species and minerals designated "TCM formulae" developed based on TCM theory and clinical experience. TCM formulae have been shown to exert curative effects on complex diseases via immune regulation but the underlying mechanisms remain unknown at present. Considerable progress in the field of immunometabolism, referring to alterations in the intracellular metabolism of immune cells that regulate their function, has been made over the past decade. The core context of immunometabolism is regulation of the allocation of metabolic resources supporting host defense and survival, which provides a critical additional dimension and emerging insights into how the immune system and metabolism influence each other during disease progression. This review summarizes research findings on the significant association between the immune function and metabolic remodeling in health and disease as well as the therapeutic modulatory effects of TCM formulae on immunometabolism. Progressive elucidation of the immunometabolic mechanisms involved during the course of TCM treatment continues to aid in the identification of novel potential targets against pathogenicity. In this report, we have provided a comprehensive overview of the benefits of TCM based on regulation of immunometabolism that are potentially applicable for the treatment of modern diseases. [Display omitted] All data generated or analyzed during this study are included in this manuscript and its supplementary information files. • The interrelationships among immunometabolism, disease pathogenesis and TCM formulae are comprehensively discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this study we report the synthesis and activity against bovine viral diarrhea virus (BVDV) of a novel series of bicycle δ-sultones containing γ-lactones. BVDV is responsible for major losses in cattle. Some of the synthesized δ-sultones showed pronounced anti-BVDV activity with EC50 values of 0.12–1.0μM and no significant cytotoxicity. Among them, the ortho bromosubstituted derivative 4f (EC50 =0.12μM) showed better antiviral activity than other derivatives and was 10 fold more that of than positive control ribavirin (EC50 =1.3μM). BVDV is also considered to be a valuable surrogate for the hepatitis C virus (HCV) in antiviral drug studies. The above results provided a novel candidate for the development of anti-HCV agents. [Copyright &y& Elsevier]

Abstract: Series of 5-substituted-3,4-diphenylfuran-2-ones were stereoselectively prepared. Their potential anti-proliferative effects on prostate cancer and some of their cyclooxygenases (COXs) inhibitory activities were evaluated. Structure–activity relationship (SAR) data, acquired by substituent modification at the para-position and ortho-position of the C-3 phenyl ring and 5-substituted modification of the central furanone, showed that 3-(2-chloro-phenyl)-4-(4-methanesulfonyl-phenyl)-5-(1-methoxy-ethyl)-5H-furan-2-one (13p) was the most potent compound and could effectively reduce the proliferation of prostate cancer cells (PC3 cell IC50 = 20 μM; PC3 PCDNA cell IC50 = 5 μM; PC3 SKP2 cell IC50 = 5 μM; DU145 cell IC50 = 25 μM). The cell cycle analysis for 13p in DU145 indicated that 13p may induce G1 phase arrest. [Copyright &y& Elsevier]

Abstract: A series of novel 1,2,3-triazole–dithiocarbamate–urea hybrids were designed, synthesized and their antiproliferative activities against four selected human cancer cell lines were evaluated. The results showed that a number of the hybrids exhibited potent activity in selected human cancer cell lines. Among them, compounds 27 and 34 showed broad spectrum anticancer activity with IC50 values ranging from 1.62 to 20.84 μM and 0.76 to 13.55 μM, respectively. Interestingly, compounds 27 and 34, being very potent against MGC-803 cells, exhibited no significant cytotoxicity against normal human embryonic kidney cells at up to 55 μM and 70 μM, respectively. Evidences of cell cycle arrest and apoptosis induction were obtained for the most effective compounds 27 and 34 by means of flow cytometry and microscopic techniques. [Copyright &y& Elsevier]

Abstract: Three series of butenolide-containing dithiocarbamates were designed and synthesized. Their anti-tumor activity in vitro was evaluated. Among them compound I-14 exhibited broad spectrum anti-cancer activity against five human cancer cell lines with IC50 <30μM. Structure–activity relationship analysis showed that the introduction of dithiocarbamate side chains on the C-3 position of butenolide was crucial for anti-tumor activity. [Copyright &y& Elsevier]