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The photonic router is a key device in optical communication and quantum networks. Here, the results of a study of multi‐channel optical routing using optomechanical multimode interference in an optical microcavity are reported. The optomechanical system used here exhibits multi‐optical modes and a mechanical mode. Optomechanical induced transparency and absorption appear in the system due to the interference between different paths. It is shown that the system can be served as a three‐port routing in the red‐detuned region to rout photons from the input port to an arbitrarily selected output port with high routing efficiency by controlling the parameters corresponding to different interference paths. [ABSTRACT FROM AUTHOR]

By preparing a sensor system around isolated exceptional points, one can obtain a great enhancement of the sensitivity benefiting from the non‐Hermiticity. However, this comes at the cost of reduction of the flexibility of the system, which is critical for practical applications. By generalizing the exceptional points to exceptional surfaces, it has been theoretically proposed recently that enhanced sensitivity and flexibility can be combined. Here, an exceptional surface is experimentally demonstrated in a non‐Hermitian photonic sensing system, which is composed of a whispering‐gallery‐mode microresonator and two nanofiber waveguides, resulting in a unidirectional coupling between two degenerate counter‐propagating modes with an external optical isolator. The system is simple, robust, and can be easily operated around an exceptional surface. On the one hand, sensitivity enhancement is observed by monitoring the resonant frequency splitting caused by small perturbations. This demonstration of exceptional‐surface‐enhanced sensitivity paves the way for practical non‐Hermitian sensing applications. On the other hand, the suppression of frequency splitting around the exceptional surface is also shown for the first time. [ABSTRACT FROM AUTHOR]

High-sensitivity gyroscope is widely used for rotation detection in several practical applications. Recently, exceptional points (EPs) have garnered considerable attention for enhancing the sensitivity of sensors based on optical cavities. Here, we propose an EP-enhanced optical gyroscope based on mechanical parity-time (PT) symmetry in a microcavity system. We demonstrate that by pumping the two optical modes with different colors, i.e., blue and red detuning, an effective mechanical PT-symmetric system can be obtained, and the system can be prepared at EP with appropriate parameters. The sensitivity of gyroscope at EP was enhanced by more than one order of magnitude in the weak perturbation regime as compared to that at diabolic point. This indicates that the sensitivity of gyroscope can be effectively enhanced by monitoring the mechanical modes rather than the optical modes. Overall, our work provides a promising approach to design high-sensitivity gyroscopes in optical microcavities and is potentially useful in a variety of research fields including fundamental physics and precision measurement. [ABSTRACT FROM AUTHOR]

In article number 2000506, Gui#x02010;Lu Long and co#x02010;workers report the results of a study of multi#x02010;channel optical routing using optomechanical multimode interference in an optical microcavity. They show three#x02010;port routing in the red#x02010;detuned region to rout photons from the input port to an arbitrarily selected output port with high routing efficiency with this system. Photonic Routers: Multimode Interference Induced Optical Routing in an Optical Microcavity (Ann. [Extracted from the article]

In article number 2000569 by Haitan Xu, Fuchuan Lei, Dong Ruan, Gui-Lu Long, and co-workers, exceptional surfaces are experimentally realized in the higher-dimensional synthetic space. The sensor operating at an exceptional surface combines enhanced sensitivity with flexible experimental conditions. Exceptional Surface-Based Sensors: Experimental Realization of Sensitivity Enhancement and Suppression with Exceptional Surfaces (Laser Photonics Rev. 15(5)/2021). [Extracted from the article]

The phytochemical investigation of the aerial parts of Isodon japonica var. glaucocalyx afforded four undescribed (glaucocalyxin O-R, 1 – 4) and six known ent -kauranoids (5 – 10). Their structures were established using NMR and MS measurements. Compounds 1 and 2 are dimeric ent- kaurane-type diterpenoids. Moreover, the plausible biogenetic pathways for compounds 1 and 2 were proposed as Michael addition between two monomers. Eight compounds were assayed for their anti-inflammatory activity by evaluating NO production in LPS-induced RAW 267.4 cells, and compounds 7 , 8 and 9 exhibited relatively remarkable anti-inflammatory activities at 10 μM. [Display omitted] • Four undescribed diterpenoids were isolated from Isodon japonica var. glaucocalyx. • Compounds 1 and 2 are dimeric ent- kaurane-type diterpenoids. • Compounds 7, 8 and 9 exhibitedremarkable anti-inflammatory activities at 10 μM. [ABSTRACT FROM AUTHOR]

Insect gut bacteria play an essential role in the nutritional metabolism, growth, and development of insects. Grasshoppers (Orthoptera) are cellulose-rich plant-feeding pests. Although the biological potential of grasshopper gut microorganisms to assist cellulose decomposition is well established, microbial resources for efficient degradation of cellulose biomass are still scarce and need to be developed. In this study, we used selective media to isolate cellulose-degrading bacteria from the intestines of Atractomorpha sinensis, Trilophidia annulata, Sphingonotus mongolicus , and Calliptamus abbreviatus. Phylogenetic analysis based on the maximum likelihood method using 16S rDNA sequencing sequences to identify bacteria revealed the isolation of 11 strains belonging to 3 genera, including Klebsiella , Aeromonas , and Bacillus. The degradability of the isolates to cellulose was then determined by the DNS colorimetric method, and the results showed that Bacillus had the highest degradation rate. The elucidation of microbial cellulose degradation capacity in grasshoppers not only contributes to the understanding of multiple plant–insect–microbe interactions, but also provides a valuable microbial resource for solving the biomass conversion of cellulose species problem. [ABSTRACT FROM AUTHOR]

Thirteen previously undescribed iridoids (1 – 13), together with five known iridoids (14 – 18) were isolated from the roots and rhizomes of Valeriana jatamansi Jones. Their structures with absolute configurations were elucidated by analysis of MS, NMR, optical rotation and their experimental and calculated electronic circular dichroism spectra. All of the isolated compounds were tested for their protective effects against α-hemolysin-induced cell death in A549 cells. Compounds 14 , 16 and 17 showed moderate protective effects, and compounds 15 and 18 showed weak protective effects. Eighteen iridoids including thirteen previously undescribed ones were isolated from Valeriana jatamansi Jones and some of them exhibited protective effects against α-hemolysin-induced cell death in A549 cells. [Display omitted] • Thirteen previously undescribed iridoids were isolated from Valeriana jatamansi. • Compounds 1 and 2 were unique iridoids with isovaleroxy at C-1 and C-3. • Compounds 14 , 16 and 17 showed moderate protective effects against α-hemolysin. [ABSTRACT FROM AUTHOR]

Zearalenone (ZEA), a natural contaminant found in feed, has been shown to have a negative impact on domestic animal reproduction, particularly in pigs. There are species-specific differences in the ZEA-induced toxicity pattern. Here, we investigated the different biological effects of ZEA exposure on porcine and mouse granulosa cells, using RNA-seq analysis. We treated murine and porcine granulosa cells with 10 μM and 30 μM ZEA during 72 h of culturing, in vitro . The results showed that 10 μM ZEA exposure significantly altered mitosis associated genes in porcine granulosa cells, while the same treatment significantly altered the steroidogenesis associated genes in mouse granulosa cells. Exposure to 30 μM ZEA resulted in significantly up-regulated expression of inflammatory related genes in porcine granulosa cells as well as the cancer related genes in mouse granulosa cells. Similarly, 30 μM ZEA exposure significantly decreased the expression of tumor suppressor factors in the mouse granulosa cells. Furthermore, immunofluorescence, RT-qPCR as well as western-blot analysis verified the different expression of related genes in ZEA exposed porcine and mouse granulosa cells. Collectively, these results illustrate the presence of species differences with regards to ZEA effects between porcine and mouse ovarian granulosa cells, in vitro . [ABSTRACT FROM AUTHOR]

Insulin is a protein secreted by pancreatic β-cells, which plays an important role in the regulation of ovarian function. However, the specific molecular mechanism of its function remains largely unknown. This study aimed to assess the effect of insulin on mouse folliculogenesis using an in vitro ovary-culture model. The results demonstrated that insulin promoted the proliferation of ovarian granulosa cells in vitro, and thereby accelerated the progress of folliculogenesis (the percentage of oocytes in cysts declined from 42.6% to 29.3%); however, the percentage of apoptotic oocytes increased after insulin treatment. Further investigation indicated that apoptosis occurred mainly in germ-cell cysts. After 3 days of insulin treatment, oestrogen in the culture medium of mouse ovaries significantly increased (P < 0.01), while the lower dose of oestrogen promoted primordial-follicle assembly in vitro. In conclusion, insulin promoted folliculogenesis by facilitating germ-cell apoptosis within the cysts and upregulating oestrogen levels. [ABSTRACT FROM AUTHOR]

The fatty acid dehydrogenase I ( FatI) is able to express in mammalian cells and convert n-6 polyunsaturated fatty acids ( PUFAs) to n-3 PUFAs. n-3 PUFA is an important component of the cell membrane and plays an important role in the prevention and control of a variety of human diseases. However, n-3 PUFAs cannot be endogenously synthesized by mammals because they lack the dehydrogenase that converts n-6 to n-3 PUFA. For the time being, gradually matured transgenic technology makes it possible to produce transgenic animals that are able to synthesize n-3 PUFAs by themselves. However, the transgenic technology itself may bring negative impacts. In this study, the eukaryotic expression vector pc DNA3.1-FatI was introduced into the genome of Boer goat fetal fibroblasts cultured in vitro, and the influence of biological characteristics of the fetal fibroblast was studied via overexpression of FatI. The results showed that the proliferation and apoptosis of cultured fetal fibroblast were not affected significantly by the overexpression of FatI using BrdU and TUNEL staining methods, respectively. Moreover, the overexpression of FatI significantly inhibited the senescence of somatic cells compared with enhanced green fluorescent protein ( EGFP) transgenic cells ( P < 0.01). Quantitative PCR revealed that the m RNA expression of P16 and P53 in the FatI transgenic cell group was significantly lower than that in the EGFP transgenic cell group ( P < 0.01). In conclusion, the senescence of goat somatic cells was inhibited by the overexpression of the FatI gene. [ABSTRACT FROM AUTHOR]

Currently, n-3 polyunsaturated fatty acids (n-3 PUFAs) have attracted great attention because of their biological significance to organisms. In addition, PUFAs show an obvious impact on prevention and treatment of various diseases. Because n-3 PUFAs cannot be endogenously synthesized by mammals, mammals have to rely on a dietary supplement for sufficient supply. The finding and application of the fatty acid dehydrogenase I ( FatI) gene are expected to change the current situation because it can convert n-6 polyunsaturated fatty acids (n-6 PUFAs) to n-3 PUFAs. Meanwhile, the gradual maturation of transgenic technology makes it possible to produce transgenic animals that can synthesize n-3 PUFAs by themselves. In this study, the DNA coding sequence of FatI was synthesized by a chemical method after codon optimization according to the mammal's codon bias. The synthesized DNA sequence was introduced into Boer goat fetal fibroblasts by the constructed recombinant eukaryotic expression vector pcDNA3.1(+)-FatI. Boer goat fetal fibroblasts were transfected by electroporation, and the stable transfected cell lines were obtained by G418 selection. Genomic DNA PCR and Southern blot were applied to verify that the foreign gene FatI was integrated into the genome of the Boer goat fibroblasts. RT- PCR results showed the expression of FatI gene at the m RNA level. The fatty acid profile of cells carrying the FatI gene revealed an increase in total n-3 PUFAs (from 0.61 to 0.95), but a decrease in n-6 PUFAs (from 10.34 to 9.85), resulting in a remarkable increase in the n-3:n-6 ratio (from 0.059 to 0.096). The n-3:n-6 ratio had a 63.49 percent increase, which is a precursor of the response of n-3 desaturase activity of the FatI gene. The study may provide a practical tool for producing transgenic animals that can produce n-3 PUFAs by themselves, and we hope that the application will lay the foundation for animals producing n-3 PUFAs, which will benefit human nutrition and wellness. [ABSTRACT FROM AUTHOR]

Fabricating an optical microtoroid with ultra-high quality factor is an indispensable procedure both for scientific research and engineering. Here, HF/HNO 3 wet etching is specially tailored to form silicon pillars for ultra-high quality factor microtoroids instead of xenon difluoride (Xe F 2) or reactive ion etching (RIE) methods. This is a low-cost, easily maintained and time-saving method. The method uses a very simple etching device and is robust to temperature variations and humidity changes at room temperature(20–25 °C). Anisotropy in isotropic HF/HNO 3 etching, which may limit the quality factor, is minimized in the experiment. Quality factor dependence on silicon orientation is experimentally investigated and theoretically explained with group theory, which shows that [111] oriented silicon wafers are superior to [100] and [110] in the wet etching method. The maximum quality factor observed at 1550 nm waveband in the experiment is 1.05 × 10 8. We believe this technique will have great influence both on laboratory and future production use. • A low-cost, easily maintained and time-saving method to fabricate ultra-high quality factor microtoroids by HF/HNO 3 wet etching. • The method is robust to temperature variations and humidity changes. • Quality factor dependence on silicon orientation is experimentally investigated and theoretically explained. [ABSTRACT FROM AUTHOR]

Bioassay-guided fractionation of the ethanol extract of whole herbs of Achilleaalpina led to the isolation of isochlorogenic acids A and B as transient receptor potential vanilloid 3 (TRPV3) channel antagonists by using a calcium fluorescent assay. The structures were identified by spectroscopic analysis and the inhibitory activities of isochlorogenic acids A and B were confirmed by whole-cell patch clamp recordings of human embryonic kidney 293 (HEK293) cells expressing human TRPV3. Molecular docking results revealed that these two compounds reside in the same active pocket of human TRPV3 channel protein with lower binding energy than the agonist 2-aminoethoxydiphenyl borate (2-APB). High-speed counter-current chromatography (HSCCC) coupled with a liquid-liquid extraction approach was successfully established for the separation of isochlorogenic acids A and B from the whole herbs of A. alpina. Ethyl acetate and n-hexane-ethyl acetate-water (3:3:4 and 1:5:4, v/v/v) were selected as liquid-liquid extraction solvent systems to remove high- and low-polarity impurities in the mixture. Sixty g of ethanol extract was refined by solvent partition to yield 1.7 g of the enriched fraction, of which 480 mg in turn obtained 52.5 mg of isochlorogenic acid B (purity 98.3%) and 37.6 mg isochlorogenic acid A (purity 96.2%) after HSCCC with n-hexane-ethyl acetate-water containing 1% acetic acid (1:4:8, v/v/v). [ABSTRACT FROM AUTHOR]