Tailored Fabrication of Full-Color Ultrastable Room-Temperature Phosphorescence Carbon Dots Composites with Unexpected Thermally Activated Delayed Fluorescence.

The development of single-system materials that exhibit both multicolor room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) with tunable after glow colors and channels is challenging. In this study, four metal-free carbon dots (CDs) are developed through structural tailoring, and panchromatic high-brightness RTP is achieved via strong chemical encapsulation in urea. The maximum lifetime and quantum yield reaches 2141 ms and 56.55%, respectively. Moreover, CDs-IV@urea, prepared via coreshell interaction engineering, exhibits a dual afterglow of red RTP and green TADF. The degree of conjugation and functional groups of precursors affects the binding interactions of the nitrogen cladding on CDs, which in turn stabilizes triplet energy levels and affects the energy gap between S1 and T1 (ΔEST) to induce multicolor RTP. The enhanced wrapping interaction lowers the ΔEST, promoting reverse intersystem crossing, which leads to phosphorescence and TADF. This strong coreshell interaction fully stabilizes the triplet state, thus stabilizing the material in water, even in extreme environments such as strong acids and oxidants. These afterglow materials are tested in multicolor, time, and temperature multiencryption as well as in multicolor in vivo bioimaging. Hence, these materials have promising practical applications in information security as well as biomedical diagnosis and treatment.

High-throughput screening for aroma production in food fermentations.

A microtiter plate (MTP) method was developed to screen 1064 unique microorganisms-substrate fermentations for production of 68 target aroma compounds. Based on the number of hits identified by GC-MS, 50 fermentations were repeated at 50-mL scale in flasks. Comparison of GC-MS data showed that scaling up from MTP to flask did not generally result in large differences between the volatile profiles, even with a wide variety of substrates (juice, food slurry and food side-streams) and microorganisms (yeast, bacteria and fungi) used. From the screening results, Lactobacillus plantarum fermentation of chilli pepper was further studied as a high amount of phenols, especially guaiacol and 4-ethylphenol, was produced after fermentation. From HPLC-MS and sensory analysis, capsaicin was shown to be a probable precursor for these phenols and a potential mechanism was proposed. The protocol described herein to screen aroma compounds from fermentation of agri-food products and side streams can support development of clean label flavourful food ingredients.

Positive effects of lignocellulose on the formation and stability of aerobic granular sludge.

Introduction: Lignocellulose is one of the major components of particulate organic matter in sewage, which has a significant influence on biological wastewater treatment process. However, the effect of lignocellulose on aerobic granular sludge (AGS) system is still unknown. Methods: In this study, two reactors were operated over 5 months to investigate the effect of lignocellulose on granulation process, structure stability and pollutants removal of AGS. Results and discussion: The results indicated that lignocellulose not only promoted the secretion of tightly bound polysaccharide in extracellular polymeric substances, but also acted as skeletons within granules, thereby facilitating AGS formation, and enhancing structural strength. Lignocellulose imposed little effect on the removal efficiency of pollutants, with more than 95, 99, and 92% of COD, NH4+-N, and PO43--P were removed in both reactors. However, it did exhibit a noticeable influence on pollutants conversion processes. This might be due to that the presence of lignocellulose promoted the enrichment of functional microorganisms, including Candidatus_Accumulibacter, Candidatus_Competibacter, Nitrosomonas, and Nitrospira, etc. These findings might provide valuable insights into the control strategy of lignocellulose in practical AGS systems.

Co-doped CeO2/N-C nanorods as a bifunctional oxygen electrocatalyst and its application in rechargeable Zn-air batteries.

The development of electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) with high-activity and atability still remain great challenges for rechargeable Zn-air batteries. Herein, a new type of Co-doped Ce-N-C bifunctional electrocatalyst has been synthesized through a simple two-step method, which realizes the high dispersion of Co3O4on the CeO2carbon frame and stabilizes its specific surface area. Benefiting from the synergistic interaction between Co3O4and CeO2, the conductivity of the electrocatalyst is improved and the oxygen reduction reaction/oxygen storage properties are promoted. The resultant Co3O4-CeO2@N-C catalyst shows remarkable ORR activity with the high initial potential (E0 = 0.8 V), the large limiting current density (jL = 6 mA cm-2), and a low Tafel slope (81 mV dec-1). In full cell tests, Co3O4-CeO2@NC as the oxygen electrode exhibites superior charge/discharge capacity and excellent cycle stability. The assembled Zn-air battery achieves a maximum power density of 110 mW cm-2at a current density of 180 mA cm-2, and a high specific capacity of 780 mAh g-1at a discharge current density of 10 mA cm-2.

Phytohormones in postharvest storage of fruit and vegetables: mechanisms and applications.

As a ubiquitous and essential part of phytophysiology, phytohormones have attracted tremendous attention for effective regulation of development and senescence of agricultural products. However, the postharvest mechanisms of phytohormones have not been thoroughly understood. This review provides an overview of common phytohormones for extending the shelf life of fruit and vegetables. The modulation principles are discussed in detail based on defence gene expression activation, sensitivity of senescence-related phytohormones inhibition, antioxidant enzymes activity stimulation, and cell membrane integrity maintenance. The applications of jasmonates, salicylic acids, cytokinins, gibberellins, polyamines, and brassinosteroids in preserving fruit and vegetables based on defence signaling network stimulation, senescence-related phytohormones expression or sensitivity repression, as well as antioxidant system enhancement and cell membrane integrity sustentation are introduced. The challenges and problems to be solved are discussed, and new trends of expanding lifespan by combining phytohormones with other treatments are also suggested. Although phytohormones have been demonstrated to have promising efforts in maintaining agricultural products, more novel and effective combination treatments should be developed to complement each other.

Tousled-like kinase regulates cytokine-mediated communication between cooperating cell types during collective border cell migration.

Collective cell migration is emerging as a major contributor to normal development and disease. Collective movement of border cells in the Drosophila ovary requires cooperation between two distinct cell types: four to six migratory cells surrounding two immotile cells called polar cells. Polar cells secrete a cytokine, Unpaired (Upd), which activates JAK/STAT signaling in neighboring cells, stimulating their motility. Without Upd, migration fails, causing sterility. Ectopic Upd expression is sufficient to stimulate motility in otherwise immobile cells. Thus regulation of Upd is key. Here we report a limited RNAi screen for nuclear proteins required for border cell migration, which revealed that the gene encoding Tousled-like kinase (Tlk) is required in polar cells for Upd expression without affecting polar cell fate. In the absence of Tlk, fewer border cells are recruited and motility is impaired, similar to inhibition of JAK/STAT signaling. We further show that Tlk in polar cells is required for JAK/STAT activation in border cells. Genetic interactions further confirmed Tlk as a new regulator of Upd/JAK/STAT signaling. These findings shed light on the molecular mechanisms regulating the cooperation of motile and nonmotile cells during collective invasion, a phenomenon that may also drive metastatic cancer.

ß-Orcinol-type depsides from the lichen Thamnolia vermicularis.

A phytochemical investigation of a herb tea made from Thamnolia vermicularis led to the isolation of three new ß-orcinol-type depsides (1, 2 and 3), along with seven known compounds hypothamnolic acid (4), 3'-methylevenic acid (5), baeomycesic acid (6), squamatic acid (7), methyl 3'-methyllecanorate (8), barbatinic acid (9) and atranorin (10). The structures of the new compounds were determined on the basis of spectroscopic evidence, including 1-D and 2-D NMR and ESI-MS techniques.

New dammarane-type glycosides from the roots of Gynostemma pentaphyllum.

Twelve new dammarane-type glycosides ( 1- 12) were isolated from the ethanol extract from the roots of a wild-type of Gynostemma pentaphyllum. The structures of the compounds were elucidated by 1D and 2D NMR spectroscopic analysis as well as by chemical degradation. The compounds contained six structurally diverse aglycons similar to those of the reported ginseng saponins with differences in the oligosaccharide moieties.

Diterpenoids from Euphorbia neriifolia.

Nine diterpenoids were isolated from the stems of Euphorbia neriifolia Linn. with their structures established by 1D and 2D NMR techniques. Relative stereochemistries were determined by ROESY, and single-crystal X-ray experiments.

Neolignans and flavonoids from the root bark of Illicium henryi.

Two new neolignans (1 and 2) were isolated from the root bark of Illicium henryi, along with four known neolignans and seven known flavonoids (3-13). Their structures were elucidated on the basis of spectroscopic and chemical methods. The absolute configurations of compounds 1 and 2 were determined by the CD spectrum.

Dammarane-type glycosides and long chain sesquiterpene glycosides from Gynostemma yixingense.

A new dammarane-type glycoside and a new long chain sesquiterpene glycoside, along with nine known compounds 20(S)-ginsenoside Rh1 (3), 20(R)-ginsenoside Rh1 (4), ginsenoside F1 (4), amarantholidoside IV (6), ginsenoside Rc (7), 20(S)-ginsenoside Rg2 (8), 20(R)-ginsenoside Rg2 (9), ginsenoside Rd (10) and gypenoside XLVI (11) were isolated from Gynostemma yixingense. The structures of the new compounds were determined on the basis of spectroscopic analysis, including 1D-, 2D-NMR and ESI-MS techniques as well as by comparison of the spectral data with those of related compounds as 2 alpha,3beta,20(S)-trihydroxydammar-24-ene-3-O-[beta-D-glucopyranosyl((1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyranosyl((1-->6)-beta-D-glucopyranoside] (1) (2E,6E)-10-beta-D-glucopyranosyl-1,10,11-trihydroxy-3,7,11-trimethyldodeca-2,6-diene (2).

Role of Scrib and Dlg in anterior-posterior patterning of the follicular epithelium during Drosophila oogenesis.

BACKGROUND: Proper patterning of the follicle cell epithelium over the egg chamber is essential for the Drosophila egg development. Differentiation of the epithelium into several distinct cell types along the anterior-posterior axis requires coordinated activities of multiple signaling pathways. Previously, we reported that lethal(2)giant larvae (lgl), a Drosophila tumor suppressor gene, is required in the follicle cells for the posterior follicle cell (PFC) fate induction at mid-oogenesis. Here we explore the role of another two tumor suppressor genes, scribble (scrib) and discs large (dlg), in the epithelial patterning. RESULTS: We found that removal of scrib or dlg function from the follicle cells at posterior terminal of the egg chamber causes a complete loss of the PFC fate. Aberrant specification and differentiation of the PFCs in the mosaic clones can be ascribed to defects in coordinated activation of the EGFR, JAK and Notch signaling pathways in the multilayered cells. Meanwhile, the clonal analysis revealed that loss-of-function mutations in scrib/dlg at the anterior domains result in a partially penetrant phenotype of defective induction of the stretched and centripetal cell fate, whereas specification of the border cell fate can still occur in the most anterior region of the mutant clones. Further, we showed that scrib genetically interacts with dlg in regulating posterior patterning of the epithelium. CONCLUSION: In this study we provide evidence that scrib and dlg function differentially in anterior and posterior patterning of the follicular epithelium at oogenesis. Further genetic analysis indicates that scrib and dlg act in a common pathway to regulate PFC fate induction. This study may open another window for elucidating role of scrib/dlg in controlling epithelial polarity and cell proliferation during development.

WITHDRAWN: Eight new C21 steroidal glycosides from Cynanchum wilfordii.

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