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The wide application of optical spectroscopy makes miniaturized spectrometers with fundamental importance. The scalability, high-performance, low-cost, and small footprint are still contradicting each other and limiting the applicability of miniaturized spectrometer for practical application. Here we propose a compact spectrometer that satisfies the four advantages. The device uses a fiber taper tip to generate complex leaky mode patterns within 1 mm length. The unique correspondence between the pattern and wavelength operates effectively for hundreds of nanometers spectral range while providing a spectral resolution around ~ 1 pm. The integration of multiple taper tips enables hyperspectral imaging applications. The working range of our device can be further extended using different materials and detectors while keeping the similar architecture.

Postharvest deterioration is among the major challenges for the fruit industry. Regulation of the fruit softening rate is an effective strategy for extending shelf-life and reducing the economic losses due postharvest deterioration. The tomato myoinositol monophosphatase 3 gene SlIMP3, which showed highest expression level in fruit, was expressed and purified. SlIMP3 demonstrated high affinity with the L-Gal 1-P and D-Ins 3-P, and acted as a bifunctional enzyme in the biosynthesis of AsA and myoinositol. Overexpression of SlIMP3 not only improved AsA and myoinositol content, but also increased cell wall thickness, improved fruit firmness, delayed fruit softening, decreased water loss, and extended shelf-life. Overexpression of SlIMP3 also increased uronic acid, rhamnose, xylose, mannose, and galactose content in cell wall of fruit. Treating fruit with myoinositol obtained similar fruit phenotypes of SlIMP3-overexpressed fruit, with increased cell wall thickness and delayed fruit softening. Meanwhile, overexpression of SlIMP3 conferred tomato fruit tolerance to Botrytis cinerea. The function of SlIMP3 in cell wall biogenesis and fruit softening were also verified using another tomato species, Ailsa Craig (AC). Overexpression of SlDHAR in fruit increased AsA content, but did not affect the cell wall thickness or fruit firmness and softening. The results support a critical role for SlIMP3 in AsA biosynthesis and cell wall biogenesis, and provide a new method of delaying tomato fruit softening, and insight into the link between AsA and cell wall metabolism.

Summary Unicellular and multicellular tomato trichomes function as mechanical and chemical barriers against herbivores. Auxin treatment increased the formation of II, V and VI type trichomes in tomato leaves. The auxin response factor gene SlARF4, which was highly expressed in II, V and VI type trichomes, positively regulated the auxin‐induced formation of II, V and VI type trichomes in the tomato leaves. SlARF4 overexpression plants with high densities of these trichomes exhibited tolerance to spider mites. Two R2R3 MYB genes, SlTHM1 and SlMYB52, were directly targeted and inhibited by SlARF4. SlTHM1 was specifically expressed in II and VI type trichomes and negatively regulated the auxin‐induced formation of II and VI type trichomes in the tomato leaves. SlTHM1 down‐regulation plants with high densities of II and VI type trichomes also showed tolerance to spider mites. SlMYB52 was specifically expressed in V type trichomes and negatively regulated the auxin‐induced formation of V type trichome in the tomato leaves. The regulation of SlARF4 on the formation of II, V and VI type trichomes depended on SlTHM1 and SlMYB52, which directly targeted cyclin gene SlCycB2 and increased its expression. In conclusion, our data indicates that the R2R3 MYB‐dependent auxin signalling pathway regulates the formation of II, V and VI type trichomes in tomato leaves. Our study provides an effective method for improving the tolerance of tomato to spider mites.

It is critical for tourism managers and marketers to understand how to support the sustainable recovery of the industry by involving residents in tourism marketing. The purpose of this study is to investigate whether the COVID-19 pandemic, as an environmental stimulus, could enhance the salience of residents’ collective identity, thereby increasing their engagement with place branding. A conceptual framework was developed to explore the role of relationship-inducing factors and non-relationship-inducing factors in activating residents’ collective identity based on the social identity salience theory of relationship marketing success. The research model was tested using data from 603 questionnaires collected from Sanya, China, during the period of a sudden COVID-19-related crisis. The findings from the statistical analyses showed significant relationships among the research variables, and the moderating role of perceived social connectedness was supported. Our findings have implications regarding how to engage residents in the tourism recovery process during and post the COVID-19 pandemic.

Autonomic dysfunction is common in transthyretin familial amyloid polyneuropathy (TTR-FAP). Because ultrasonography is a powerful tool to study peripheral neuropathy, vagus nerve (VN) ultrasonography was used in our study to investigate the possible changes of the dimension of VN in TTR-FAP.Eighteen patients with TTR-FAP and 17 age- and gender-matched individuals without any neuropathies were enrolled in a pilot study. The cross-sectional areas (CSAs) were measured bilaterally on transverse scans of vagus, median, and ulnar nerves. Clinical data were collected to explore the correlations with CSAs of VN.The median CSAs of VN in TTR-FAP were 3.5 (2.0-6.0) mmVN enlargement is prevalent among TTR-FAP patients. VN ultrasonography may be an important clinical tool for assessing the severity of autonomic dysfunction in TTR-FAP.

Enzyme-catalyzed electrolysis system (EES) is a promising technique for the efficient dechlorination of pollutants. In this study, ionic liquids (ILs) was first introduced to enhance the dichloromethane dechlorination performance of an EES. An imidazole-based IL, 1-ethyl-3-methylimidazole tetrafluoroborate ([EMIM][BF4]), was chosen due to its excellent performance on dechlorination enhancement than other three ILs. The cyclic voltammograms with different scan rates shows that the presence of IL increased the apparent electron transfer rate constant (ks) from 0.008 to 0.013 s−1. The calculated surface electroactive species concentration (τc) also increased from 7.8 × 10−9 to 9.5 × 10−9 mol cm−2. Electrochemical impedance spectroscopy analysis illustrates that the IL mainly weakened the interfacial resistance between electrolyte and cathode to accelerate the electron communication in the EES. The introduction of IL facilitated the regeneration of reduced glutathione from oxidized glutathione, whereas inhibited the catalytic activity of dehalogenase via the disruption of secondary structure shown in circular dichroism spectra. The presence of IL was also facilitated the dichloromethane diffusion from electrolyte to cathode. The mass transfer rate constants of dichloromethane (km,d) increased by 6.9 times after the addition of IL. The optimum volume concentration, pH value, reaction temperature and applied voltage were 20%, 7, 35 °C and −0.8 V vs Ag/AgCl, respectively. The study is helpful to understand the promotion mechanism of IL on the dechlorination performance of EES when it is adopted as a treatment technique.

Hierarchical porous carbons are successfully prepared from a readily water-soluble biomass sodium alginate with the assistance of Fe3+ and Ni2+ via a simple sol–gel method. The drying method and separation ways of ionically-crosslinked alginate gels could significantly affect the morphologies of the precursors and the porous structures for the carbons. By adjusting the amounts of FeCl3·6H2O, we can prepare hierarchical porous carbons and target the surface area and pore volume. The results show that the porous carbons exhibit superior electrochemical behaviors when they are used as anode materials for lithium-ion batteries. Both the porous structures and the assembly way of graphene sheets in the carbon materials play important roles in their electrochemical properties.

Malaria is the most devastating parasitic disease worldwide. Artemisinin is the only drug that can cure malaria that is resistant to quinine-derived drugs. After the commercial extraction of artemisinin from Artemisia annua, the recovery of dihydroartemisinic acid (DHAA) from artemisinin extraction by-product has the potential to increase artemisinin commercial yield. Here we describe the development and optimization of an ultrasound-assisted alkaline procedure for the extraction of DHAA from artemisinin production waste using response surface methodology. Our results using this methodology established that NaOH at 0.36%, extraction time of 67.96 min, liquid-solid ratio of 5.89, and ultrasonic power of 83.9 W were the optimal conditions to extract DHAA from artemisinin production waste. Under these optimal conditions, we achieved a DHAA yield of 2.7%. Finally, we conducted a validation experiment, and the results confirmed the prediction generated by the regression model developed in this study. This work provides a novel way to increase the production of artemisinin per cultivated area and to reduce artemisinin production costs by recycling its commercial waste to obtain DHAA, an immediate precursor of artemisinin. The use of this technology may reduce the costs of artemisinin-based antimalarial medicines.

Auxin response factors (ARFs) are involved in auxin-mediated transcriptional regulation in plants. In this study, we performed functional characterization of SlARF6A in tomato. SlARF6A is located in the nucleus and exhibits transcriptional activator activity. Overexpression of SlARF6A increased chlorophyll contents in the fruits and leaves of tomato plants, whereas downregulation of SlARF6A decreased chlorophyll contents compared with those of wild-type (WT) plants. Analysis of chloroplasts using transmission electron microscopy indicated increased sizes of chloroplasts in SlARF6A-overexpressing plants and decreased numbers of chloroplasts in SlARF6A-downregulated plants. Overexpression of SlARF6A increased the photosynthesis rate and accumulation of starch and soluble sugars, whereas knockdown of SlARF6A resulted in opposite phenotypes in tomato leaves and fruits. RNA-sequence analysis showed that regulation of SlARF6A expression altered the expression of genes involved in chlorophyll metabolism, photosynthesis and sugar metabolism. SlARF6A directly bound to the promoters of SlGLK1, CAB, and RbcS genes and positively regulated the expression of these genes. Overexpression of SlARF6A also inhibited fruit ripening and ethylene production, whereas downregulation of SlARF6A increased fruit ripening and ethylene production. SlARF6A directly bound to the SAMS1 promoter and negatively regulated SAMS1 expression. Taken together, these results expand our understanding of ARFs with regard to photosynthesis, sugar accumulation and fruit development and provide a potential target for genetic engineering to improve fruit nutrition in horticulture crops.

In order to make full use of artemisinin production waste and thus to reduce the production cost of artemisinin, we developed an efficient and scalable method to isolate high-purity dihydroartemisinic acid from artemisinin production waste by combining anion-exchange resin with silica-gel column chromatography. The adsorption and desorption characteristics of dihydroartemisinic acid on 10 types of anion-exchange resin were investigated, and the results showed that the 717 anion-exchange resin exhibited the highest capacity of adsorption and desorption to dihydroartemisinic acid. Adsorption isotherms were established for the 717 anion-exchange resin and they fitted well with both Langmuir and Freundlich model. Dynamic adsorption and desorption properties of 717 anion-exchange resin were characterized to optimize the chromatographic conditions. Subsequently, the silica-gel column chromatography was performed and dihydroartemisinic acid with a purity of up to 98% (w/w) was obtained. Finally, the scale-up experiments validated the preparative separation of high-purity dihydroartemisinic acid from industrial waste developed in the present work. This work presented for the first time an isolation of dihydroartemisinic acid with a purity of 98% from Artemisia annua (A. annua) by-product, which adds more value to this crop and has the potential to lower the prices of anti-malarial drugs.

Canola is an important vegetable oil crop globally, and the understanding of the molecular mechanism underlying fatty acids biosynthesis during seed embryo development is an important research goal. Here we report the transcriptional profiling analysis of developing canola embryos using RNA-sequencing (RNA-Seq) method. RNA-Seq analysis generated 58,579,451 sequence reads aligned with 32,243 genes. It was found that a total of 55 differential expression genes (DEGs) encoding 28 enzymes function in carbon flow to fatty acids of storage TAG. Most of the DEGs encoding above enzymes showed similar expression pattern, indicating the DEGs are cooperatively involved in carbon flow into fatty acids. In addition, 41 DEGs associated with signal transductions, transport and metabolic processing of auxin, gibberellin, abscisic acid, cytokinin and salicylic acids were found in the RNA-Seq database, which indicates the important roles of the phytohormones in controlling embryo development and fatty acids synthesis. 122 DEGs encoding transcriptional factor family members were found in developing canola embryos. Furthermore, BnDOF5.6, a zinc finger transcriptional factor gene, found in RNA-Seq database was down-regulated in developing canola embryos. The transgenic plants displayed reduced embryo sizes, decreased fatty acids contents and altered seed fatty acids composition in canola. Down-regulated of BnDof5.6 also changed the expression levels of genes involved in fatty acids synthesis and desaturation. Our results indicate that BnDof5.6 is required for embryo development and fatty acids synthesis in canola. Overall this study presents new information on the global expression patterns of genes during embryo development and will expand our understanding of the complex molecular mechanism of carbon flow into fatty acids and embryo development in canola.

[Research background] Different social forms determine different social governance models. With the development of the Internet of things, cloud computing and artificial intelligence, digital governance has entered the big data era. [Research questions and methods] What should be the digital governance model for the big data era? Krassimira believe that applying digital governance theory to guide smart city practice is an important step in governance theory in the field of urban governance. Singapore's "Smart nation 2025" is the first blueprint for a smart nation in the world. Taking the practice of Singapore's “smart nation 2025” as a case study, based on the theory of digital governance, from the three dimensions of digital economy, digital government and digital society, using the "institutional-organization-technology-behavior" analysis framework, this paper analyzes the context framework of Singapore's digital governance model, and summarizes the typical characteristics of Singapore's digital governance model. [Conclusion] The study found that Singapore has established a digital governance model in which governments, economic society, and civil society can collaborate and interact. Singapore has accumulated a wealth of digital governance experience[Contribution and limitation] Singapore's urban development is highly mature, and its digital governance has typical particularity, but the experience and enlightenment of Singapore's digital governance practice can provide a reference path for improving China's digital governance ability.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Co-administration of gemfibrozil significantly increases the exposure of repaglinide. • CYP3A4 and CYP2C8 are important in the metabolism of repaglinide. • OATP1B1 polymorphism is an independent predictor of repaglinide pharmacokinetics. • Gemfibrozil and its O-glucuronide are CYP2C8 and OATP1B1 inhibitors. WHAT THIS STUDY ADDS • Acyl glucuronidation is a major metabolic pathway of repaglinide in vitro. • Gemfibrozil and its glucuronide inhibit the glucuronidation of repaglinide. • UGT1A1 is a major enzyme responsible for the glucuronidation of repaglinide. AIM To further explore the mechanism underlying the interaction between repaglinide and gemfibrozil, alone or in combination with itraconazole. METHODS Repaglinide metabolism was assessed in vitro (human liver subcellular fractions, fresh human hepatocytes, and recombinant enzymes) and the resulting incubates were analyzed, by liquid chromatography-mass spectrometry (LC-MS) and radioactivity counting, to identify and quantify the different metabolites therein. Chemical inhibitors, in addition to a trapping agent, were also employed to elucidate the importance of each metabolic pathway. Finally, a panel of human liver microsomes (genotyped for UGT1A1*28 allele status) was used to determine the importance of UGT1A1 in the direct glucuronidation of repaglinide. RESULTS The results of the present study demonstrate that repaglinide can undergo direct glucuronidation, a pathway that can possibly contribute to the interaction with gemfibrozil. For example, [3H]-repaglinide formed glucuronide and oxidative metabolites (M2 and M4) when incubated with primary human hepatocytes. Gemfibrozil effectively inhibited (∼78%) both glucuronide and M4 formation, but had a minor effect on M2 formation. Concomitantly, the overall turnover of repaglinide was also inhibited (∼80%), and was completely abolished when gemfibrozil was co-incubated with itraconazole. These observations are in qualitative agreement with the in vivo findings. UGT1A1 plays a significant role in the glucuronidation of repaglinide. In addition, gemfibrozil and its glucuronide inhibit repaglinide glucuronidation and the inhibition by gemfibrozil glucuronide is time-dependent. CONCLUSIONS Inhibition of UGT enzymes, especially UGT1A1, by gemfibrozil and its glucuronide is an additional mechanism to consider when rationalizing the interaction between repaglinide and gemfibrozil.

The auxin response factor (ARF) genes encode a large family of proteins involved in auxin signaling transduction. SlARF3, a member of the ARF gene family, encodes a protein containing two conserved domains, B3 and ARF, and lacking an Aux/IAA domain. Expression analysis showed that SlARF3 has a particularly high expression level in trichomes. In situ hybridization also detected the SlARF3 transcripts in epidermal pavement cells of leaves. The physiological function of SlARF3 was studied by using the RNA interference (RNAi) strategy. SlARF3-down-regulated plants exhibited decreased density of epidermal pavement cells and obviously reduced density of type I, V and VI trichomes of leaves, which indicates the important role of SlARF3 in the formation of trichomes and epidermal cells in tomato. The number of shoot xylem cells was also decreased in SlARF3-down-regulated lines. Furthermore, RNA-sequencing (RNA-Seq) analysis identified 51 differentially expressed genes (DEGs) belonging to 14 transcription factor (TF) families, such as MYB, bHLH, WD40 and C2H2 zinc finger. Twenty-seven DEGs were involved in the metabolism and signaling transduction of phytohormones, such as auxin, ethylene and gibberellin. These results indicated the important roles of the TFs and hormones in auxin-dependent transcriptional regulation of trichome formation in tomato. Taken together, our results demonstrate that SlARF3 plays an important role in the formation of epidermal cells and trichomes and reveal novel and specific functions for ARFs in tomato developmental processes.

The development and progression of prostate cancer is known to be dependent on androgens and their signaling mediated by the androgen receptor (AR). The primary therapeutic intervention involves using agents that lower serum testosterone (e.g., LHRH agonists), often in concert with an AR antagonist, such as bicalutamide. Despite a favorable initial anti-tumor response, most patients progress to the advanced hormone-refractory disease. The development of resistance to anti-androgen therapy has been shown to be associated with an increase in the levels of both AR mRNA and protein. This observation supports the concept that an AR antagonist with a significant improvement in potency as compared to bicalutamide and a broader spectrum of in vivo anti-tumor activity, including the bicalutamide-refractory human prostate tumor xenografts, may provide a significant clinical advantage in the treatment of advanced prostate cancer. This presentation will describe structure-activity relationships in a novel tetracyclic series of androgen receptor antagonists leading up to the identification of BMS-779333. It is a potent AR full antagonist, which exhibited broad spectrum efficacy in four human prostate tumor xenograft models. BMS-779333 did not exhibit agonist activity for AR mutant isoforms. Tumors that failed bicalutamide treatment were shown to retain their sensitivity to respond to BMS-779333. Transcriptomic changes in LuCaP-35 tumors treated with BMS-779333 were closer to castration than with other drug treatments. Based on its overall profile, BMS-779333 was selected for further preclinical evaluation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5782.