Catalyst-Free Dynamic Covalent C=C/C=N Metathesis Reaction for Associative Covalent Adaptable Networks.

Covalent adaptable networks (CANs), leveraging the dynamic exchange of covalent bonds, emerge as a promising material to address the challenge of irreversible cross-linking in thermosetting polymers. In this work, we explore the introduction of a catalyst-free and associative C=C/C=N metathesis reaction into thermosetting polyurethanes, creating CANs with superior stability, solvent resistance, and thermal/mechanical properties. By incorporating this dynamic exchange reaction, stress-relaxation is significantly accelerated compared to imine-bond-only networks, with the rate adjustable by modifying substituents in the ortho position of the dynamic double bonds. The obtained plasticity enables recycle without altering the chemical structure or mechanical properties, and is also found to be vital for achieving shape memory functions with complex spatial structures. This metathesis reaction as a new dynamic crosslinker of polymer networks has the potential to accelerate the ongoing exploration of malleable and functional thermoset polymers.

Semi-crystalline polymers with supramolecular synergistic interactions: from mechanical toughening to dynamic smart materials.

Semi-crystalline polymers (SCPs) with anisotropic amorphous and crystalline domains as the basic skeleton are ubiquitous from natural products to synthetic polymers. The combination of chemically incompatible hard and soft phases contributes to unique thermal and mechanical properties. The further introduction of supramolecular interactions as noncovalently interacting crystal phases and soft dynamic crosslinking sites can synergize with covalent polymer chains, thereby enabling effective energy dissipation and dynamic rearrangement in hierarchical superstructures. Therefore, this review will focus on the design principles of SCPs by discussing supramolecular construction strategies and state-of-the-art functional applications from mechanical toughening to sophisticated functions such as dynamic adaptivity, shape memory, ion transport, etc. Current challenges and further opportunities are discussed to provide an overview of possible future directions and potential material applications.

Effectiveness and safety of early lens extraction during par plana vitrectomy for proliferative diabetes retinopathy with mild cataract: a randomized clinical trial.

AIM: To evaluate the effectiveness and safety of early lens extraction during pars plana vitrectomy (PPV) for proliferative diabetic retinopathy (PDR) compared to those of PPV with subsequent cataract surgery. METHODS: This multicenter randomized controlled trial was conducted in three Chinese hospitals on patients with PDR, aged >45y, with mild cataracts. The participants were randomly assigned to the combined (PPV combined with simultaneously cataract surgery, i.e., phacovitrectomy) or subsequent (PPV with subsequent cataract surgery 6mo later) group and followed up for 12mo. The primary outcome was the change in best-corrected visual acuity (BCVA) from baseline to 6mo, and the secondary outcomes included complication rates and medical expenses. RESULTS: In total, 129 patients with PDR were recruited and equally randomized (66 and 63 in the combined and subsequent groups respectively). The change in BCVA in the combined group [mean, 36.90 letters; 95% confidence interval (CI), 30.35-43.45] was significantly better (adjusted difference, 16.43; 95%CI, 8.77-24.08; P<0.001) than in the subsequent group (mean, 22.40 letters; 95%CI, 15.55-29.24) 6mo after the PPV, with no significant difference between the two groups at 12mo. The overall surgical risk of two sequential surgeries was significantly higher than that of the combined surgery for neovascular glaucoma (17.65% vs 3.77%, P=0.005). No significant differences were found in the photocoagulation spots, surgical time, and economic expenses between two groups. In the subsequent group, the duration of work incapacity (22.54±9.11d) was significantly longer (P<0.001) than that of the combined group (12.44±6.48d). CONCLUSION: PDR patients aged over 45y with mild cataract can also benefit from early lens extraction during PPV with gratifying effectiveness, safety and convenience, compared to sequential surgeries.

A Rational Design of Bio-Derived Disulfide CANs for Wearable Capacitive Pressure Sensor.

Classic approaches to integrate flexible capacitive sensor performance are to on-demand microstructuring dielectric layers and to adjust dielectric material compositions via the introduction of insoluble carbon additives (to increase sensitivity) or dynamic interactions (to achieve self-healing). However, the sensor's enhanced performances often come with increased material complexity, discouraging its circular economy. Herein, a new intrinsic self-healable, closed-loop recyclable dielectric layer material, a fully nature-derived dynamic covalent poly(disulfide) decorated with rich H bonding and metal-catechol complexations is introduced. The polymer network possesses a mechanically ductile character with an Arrhenius-type temperature-dependent viscoelasticity. The assembled capacitive pressure sensor is able to achieve a sensitivity of up to 9.26 kPa-1, fast response/recovery time of 32/24 ms, and can deliver consistent signals of continuous consecutive cycles even after being self-healed or closed-loop recycled for real-time detection of human motions. This is expected to be of high interest for current capacitive sensing research to move toward a life-like, high performance, and circular economy direction.

Converting inorganic sulfur into degradable thermoplastics and adhesives by copolymerization with cyclic disulfides.

Converting elementary sulfur into sulfur-rich polymers provides a sustainable strategy to replace fossil-fuel-based plastics. However, the low ring strain of eight-membered rings, i.e., S8 monomers, compromises their ring-opening polymerization (ROP) due to lack of an enthalpic driving force and as a consequence, poly(sulfur) is inherently unstable. Here we report that copolymerization with cyclic disulfides, e.g., 1,2-dithiolanes, can enable a simple and energy-saving way to convert elementary sulfur into sulfur-rich thermoplastics. The key strategy is to combine two types of ROP-both mediated by disulfide bond exchange-to tackle the thermodynamic instability of poly(sulfur). Meanwhile, the readily modifiable sidechain of the cyclic disulfides provides chemical space to engineer the mechanical properties and dynamic functions over a large range, e.g., self-repairing ability and degradability. Thus, this simple and robust system is expected to be a starting point for the organic transformation of inorganic sulfur toward sulfur-rich functional and green plastics.

Dynamic Near-Infrared Circularly Polarized Luminescence Encoded by Transient Supramolecular Chiral Assemblies.

Circularly polarized luminescence (CPL) is promising for applications in many fields. However, most systems involving CPL are within the visible range; near‒infrared (NIR) CPL‒active materials, especially those that exhibit high glum values and can be controlled spatially and temporally, are rare. Herein, dynamic NIR‒CPL with a glum value of 2.5[[EQUATION]]10‒2 was achieved through supramolecular coassembly and energy transfer strategies. The chiral assemblies formed by the coassembly between adenosine triphosphate (ATP) and a pyrene derivative exhibit a red CPL signal (glum of 10‒3). The further introduction of sulfo‒cyanine5 resulted in a cooperative energy transfer process, which not only aroused the NIR CPL but also increased the glum value to 10‒2. Temporal control of these chiral assemblies was realized by introducing alkaline phosphatase to fabricate a biomimetic enzyme‒catalyzed network, allowing the dynamic NIR CPL signal to be turned on. Based on these enzyme-regulated temporally controllable dynamic CPL-active chiral assemblies, a multilevel information encryption system was further developed. Our work provides a pioneering example for constructing dynamic NIR CPL materials holding the ability to perform temporal control via the supramolecular assembly strategy, which is expected to aid in the design of supramolecular complex systems that more closely resemble natural biological systems.

Anti-inflammatory discovery of sesquiterpenoids and a jasmonic acid derivative from Artemisia stolonifera.

Eleven previously undescribed sesquiterpenoids (8-18), one undescribed jasmonic acid derivative (35) and 28 known compounds were isolated from the leaves of Artemisia stolonifera. Undescribed compounds with their absolute configurations were determined by extensive spectroscopic analysis, single-crystal X-ray diffraction and ECD calculation. Compound 8 was identified as a rare sesquiterpenoid featuring a rearranged 5/8 bicyclic ring system, whereas compound 17 was found to be an unprecedented monocyclic sesquiterpenoid with methyl rearrangement. Evaluation of biological activity showed that compounds 1-5 and 7 displayed cytotoxicity against six tumor cells. In the meantime, compounds 11, 12, 18 and 35 exhibited inhibitory effects against LPS-stimulated NO production in RAW 264.7 macrophage cells and reduced the transcription of IL-6 and IL-1ß in a dose-dependent manner at 25, 50 and 100 µM. Moreover, the anti-inflammatory-based network pharmacology and molecular docking analyses revealed potential target proteins of 11, 12, 18 and 35.

Characteristics of oxyhemoglobin during the verbal fluency task in subthreshold depression: A multi-channel near-infrared spectroscopy study.

OBJECTIVE: Subthreshold depression is an essential precursor and risk factor for major depressive disorder, and its accurate identification and timely intervention are important for reducing the prevalence of major depressive disorder. Therefore, we used functional near-infrared spectroscopic imaging (fNIRS) to explore the characteristics of the brain neural activity of college students with subthreshold depression in the verbal fluency task. METHODS: A total of 72 subthreshold depressed college students (SDs) and 67 healthy college students (HCs) were recruited, and all subjects were subjected to a verbal fluency task (VFT) while a 53-channel fNIRS device was used to collect the subjects' cerebral blood oxygenation signals. RESULTS: The results of the independent samples t-test showed that the mean oxyhemoglobin in the right dorsolateral prefrontal (ch34, ch42, ch45) and Broca's area (ch51, ch53) of SDs was lower than that of HCs. The peak oxygenated hemoglobin of SDs was lower in the right dorsolateral prefrontal (ch34) and Broca's area (ch51, ch53).The brain functional connectivity strength was lower than that of HCs. Correlation analysis showed that the left DLPFC and Broca's area were significantly negatively correlated with the depression level. CONCLUSION: SDs showed abnormally low, inadequate levels of brain activation and weak frontotemporal brain functional connectivity. The right DLPFC has a higher sensitivity for the differentiation of depressive symptoms and is suitable as a biomarker for the presence of depressive symptoms. Dysfunction in Broca's area can be used both as a marker of depressive symptoms and as a biomarker, indicating the severity of depressive symptoms.

Tailoring raloxifene into single-component molecular crystals possessing multilevel stimuli-responsive room-temperature phosphorescence.

Simultaneously achieving room-temperature phosphorescence (RTP) and multiple-stimuli responsiveness in a single-component system is of significance but remains challenging. Crystallization has been recognized to be a workable strategy to fulfill the above task. However, how the molecular packing mode affects the intersystem crossing and RTP lifetime concurrently remains unclear so far. Herein, four economic small-molecular compounds, analogues of the famous drug raloxifene (RALO), are facilely synthesized and further explored as neat single-component and stimuli-responsive RTP emitters via crystallization engineering. Thanks to their simple structures and high ease to crystallize, these raloxifene analogues function as models to clarify the important role of molecular packing in the RTP and stimuli-responsiveness properties. Thorough combination of the single-crystal structure analysis and theoretical calculations clearly manifests that the tight antiparallel molecular packing mode is the key point to their RTP behaviors. Interestingly, harnessing the controllable and reversible phase transitions of the two polymorphs of RALO-OAc driven by mechanical force, solvent vapor, and heat, a single-component multilevel stimuli-responsive platform with tunable emission color is established and further exploited for optical information encryption. This work would shed light on the rational design of multi-stimuli responsive RTP systems based on single-component organics.

Mechanically interlocked [c2]daisy chain backbone enabling advanced shape-memory polymeric materials.

The incorporation of mechanically interlocked structures into polymer backbones has been shown to confer remarkable functionalities to materials. In this work, a [c2]daisy chain unit based on dibenzo-24-crown-8 is covalently embedded into the backbone of a polymer network, resulting in a synthetic material possessing remarkable shape-memory properties under thermal control. By decoupling the molecular structure into three control groups, we demonstrate the essential role of the [c2]daisy chain crosslinks in driving the shape memory function. The mechanically interlocked topology is found to be an essential element for the increase of glass transition temperature and consequent gain of shape memory function. The supramolecular host-guest interactions within the [c2]daisy chain topology not only ensure robust mechanical strength and good network stability of the polymer, but also impart the shape memory polymer with remarkable shape recovery properties and fatigue resistance ability. The incorporation of the [c2]daisy chain unit as a building block has the potential to lay the groundwork for the development of a wide range of shape-memory polymer materials.

Category representation in primary visual cortex after visual perceptual learning.

The visual perceptual learning (VPL) leads to long-term enhancement of visual task performance. The subjects are often trained to link different visual stimuli to several options, such as the widely used two-alternative forced choice (2AFC) task, which involves an implicit categorical decision. The enhancement of performance has been related to the specific changes of neural activities, but few studies investigate the effects of categorical responding on the changes of neural activities. Here we investigated whether the neural activities would exhibit the categorical characteristics if the subjects are requested to respond visual stimuli in a categorical manner during VPL. We analyzed the neural activities of two monkeys in a contour detection VPL. We found that the neural activities in primary visual cortex (V1) converge to one pattern if the contour can be detected by monkey and another pattern if the contour cannot be detected, exhibiting a kind of category learning that the neural representations of detectable contour become less selective for number of bars forming contour and diverge from the representations of undetectable contour. Supplementary Information: The online version contains supplementary material available at 10.1007/s11571-022-09926-8.

Engineering Escherichia coli for constitutive production of monophosphoryl lipid A vaccine adjuvant.

During the COVID-19 pandemic, expedient vaccine production has been slowed by the shortage of safe and effective raw materials, such as adjuvants, essential components to enhance the efficacy of vaccines. Monophosphoryl lipid A (MPLA) is a potent and safe adjuvant used in human vaccines, including the Shingles vaccine, Shingrix. 3-O-desacyl-4'-monophosphoryl lipid A (MPL), a representative MPLA adjuvant commercialized by GSK, was prepared via chemical conversion of precursors isolated from Salmonella typhimurium R595. However, the high price of these materials limits their use in premium vaccines. To combat the scarcity and high cost of safe raw materials for vaccines, we need to develop a feasible MPLA production method that is easily scaled up to meet industrial requirements. In this study, we engineered peptidoglycan and outer membrane biosynthetic pathways in Escherichia coli and developed a Escherichia coli strain, KHSC0055, that constitutively produces EcML (E. coli-produced monophosphoryl lipid A) without additives such as antibiotics or overexpression inducers. EcML production was optimized on an industrial scale via high-density fed-batch fermentation, and obtained 2.7 g of EcML (about 135,000 doses of vaccine) from a 30-L-scale fermentation. Using KHSC0055, we simplified the production process and decreased the production costs of MPLA. Then, we applied EcML purified from KHSC0055 as an adjuvant for a COVID-19 vaccine candidate (EuCorVac-19) currently in clinical trial stage III in the Philippines. By probing the efficacy and safety of EcML in humans, we established KHSC0055 as an efficient cell factory for MPLA adjuvant production.

[Corythucha marmorata affects growth and quality of Artemisia argyi].

This study aims to investigate the impact of the invasive pest Corythucha marmorata on the growth and quality of Artemi-sia argyi. The signs of insect damage at the cultivation base of A. argyi in Huanggang, Hubei were observed. The pests were identified based on morphological and molecular evidence. The pest occurrence pattern and damage mechanism were investigated. Electron microscopy, gas chromatography-mass spectrometry(GC-MS), and high performance liquid chromatography(HPLC) were employed to analyze the microstructure, volatile oils, and flavonoid content of the pest-infested leaves. C. marmorata can cause destructive damage to A. argyi. Small decoloring spots appeared on the leaf surface at the initial stage of infestation. As the damage progressed, the spots spread along the leaf veins and aggregated into patches, causing yellowish leaves and even brownish yellow in the severely affected areas. The insect frequently appeared in summer because it thrives in hot dry conditions. After occurrence on the leaves, microscopic examination revealed that the front of the leaves gradually developed decoloring spots, with black oily stains formed by the black excrement attaching to the glandular hairs. The leaf flesh was also severely damaged, and the non-glandular hairs were broken, disor-ganized, and sticky. The content of neochlorogenic acid, cryptochlorogenic acid, isochlorogenic acids A and B, hispidulin, jaceosidin, and eupatilin at the early stage of infestation was significantly higher than that at the middle stage, and the content decreased at the last stage of infestation. The content of eucalyptol, borneol, terpinyl, and caryophyllin decreased in the moderately damaged leaves and increased in the severely damaged leaves. C. marmorata was discovered for the first time on A. argyi leaves in this study, and its prevention and control deserves special attention. The germplasm materials resistant to this pest can be used to breed C. marmorata-resis-tant A. argyi varieties.

[Prediction analysis of quality markers and resource evaluation of Artemisiae Argyi Folium based on chemical composition and network pharmacology].

This study is based on ultra-high-performance liquid chromatography(UPLC), gas chromatography-mass spectrometry(GC-MS), and network pharmacology methods to analyze and predict potential quality markers(Q-markers) of Artemisiae Argyi Folium. First, UPLC and GC-MS techniques were used to analyze the content of 12 non-volatile components and 8 volatile components in the leaves of 33 Artemisia argyi germplasm resources as candidate Q-markers. Subsequently, network pharmacology was employed to construct a "component-target-pathway-efficacy" network to screen out core Q-markers, and the biological activity of the markers was validated using molecular docking. Finally, cluster analysis and principal component analysis were performed on the content of Q-markers in the 33 A. argyi germplasm resources. The results showed that 18 candidate components, 60 targets, and 185 relationships were identified, which were associated with 72 pathways related to the treatment of 11 diseases and exhibited 5 other effects. Based on the combination of freedom and component specificity, six components, including eupatilin, cineole, ß-caryophyllene, dinatin, jaceosidin, and caryophyllene oxide were selected as potential Q-markers for Artemisiae Argyi Folium. According to the content of these six markers, cluster analysis divided the 33 A. argyi germplasm resources into three groups, and principal component analysis identified S14 as having the highest overall quality. This study provides a reference for exploring Q-markers of Artemisiae Argyi Folium, establishing a quality evaluation system, further studying its pharmacological mechanisms, and breeding new varieties.

Exploring the Depth-Dependent Microviscosity inside a Micelle Using Butterfly-Motion-Based Fluorescent Probes.

The viscosity distribution of micellar interiors from the very center to the outer surface is dramatically varied, which has been distinguished in theoretical models, yet it remains highly challenging to quantify this issue experimentally. Herein, a series of fluorophore-substituted surfactants DPAC-Fn (n = 3, 5, 7, 9, 11, 13, and 15) are developed by functionalizing the different alkyl-trimethylammonium bromides with the butterfly motion-based viscosity sensor, N,N'-diphenyl-dihydrodibenzo[a,c]phenazine (DPAC). The immersion depth of DPAC units of DPAC-Fn in cetrimonium bromide (C16TAB) micelles depends on the alkyl chain lengths n. From deep (n = 15) to shallow (n = 3), DPAC-Fn in C16TAB micelles exhibits efficient viscosity-sensitive dynamic multicolor emissions. With external standards for quantification, the viscosity distribution inside a C16TAB micelle with the size of ∼4 nm is changed seriously from high viscosity (∼190 Pa s) in the core center to low viscosity (∼1 Pa s) near the outer surface. This work provides a tailored approach for powerful micelle tools to explore the depth-dependent microviscosity of micellar interiors.

γ And ß Band Oscillation in Working Memory Given Sequential or Concurrent Multiple Items: A Spiking Network Model.

Working memory (WM) can maintain sequential and concurrent information, and the load enhances the γ band oscillation during the delay period. To provide a unified account for these phenomena in working memory, we investigated a continuous network model consisting of pyramidal cells, high-threshold fast-spiking interneurons (FS), and low-threshold nonfast-spiking interneurons (nFS) for working memory of sequential and concurrent directional cues. Our model exhibits the γ (30-100 Hz) and ß (10-30 Hz) band oscillation during the retention of both concurrent cues and sequential cues. We found that the ß oscillation results from the interaction between pyramidal cells and nFS, whereas the γ oscillation emerges from the interaction between pyramidal cells and FS because of the strong excitation elicited by cue presentation, shedding light on the mechanism underlying the enhancement of γ power in many cognitive executions.

Motorized Photomodulator: Making A Non-photoresponsive Supramolecular Gel Switchable by Light.

Introducing photo-responsive molecules offers an attractive approach for remote and selective control and dynamic manipulation of material properties. However, it remains highly challenging how to use a minimal amount of photo-responsive units to optically modulate materials that are inherently inert to light irradiation. Here we show the application of a light-driven rotary molecular motor as a "motorized photo-modulator" to endow a typical H-bond-based gel system with the ability to respond to light irradiation and create a reversible sol-gel transition. The key molecular design feature is the introduction of a minimal amount (2 mol %) of molecular motors into the supramolecular network as photo-switchable non-covalent crosslinkers. Advantage is taken of the subtle interplay of the large geometry change during photo-isomerization of the molecular motor guest and the dynamic nature of a supramolecular gel host system. As a result, a tiny amount of molecular motors is enough to switch the mechanical modulus of the entire supramolecular systems. This study proves the concept of designing photo-responsive materials with minimum use of non-covalent light-absorbing units.

[Quality of moxa from Artemisia argyi and A. stolonifera in different storage years based on simultaneous thermal analysis].

The quality of moxa is an important factor affecting moxibustion therapy, and traditionally, 3-year moxa is considered optimal, although scientific data are lacking. This study focused on 1-year and 3-year moxa from Artemisia stolonifera and A. argyi(leaf-to-moxa ratio of 10∶1) as research objects. Scanning electron microscopy(SEM), Van Soest method, and simultaneous thermal analysis were used to investigate the differences in the combustion heat quality of 1-year and 3-year moxa and their influencing factors. The results showed that the combustion of A. stolonifera moxa exhibited a balanced heat release pattern. The 3-year moxa released a concentrated heat of 9 998.84 mJ·mg~(-1)(accounting for 54% of the total heat release) in the temperature range of 140-302 ℃, with a heat production efficiency of 122 mW·mg~(-1). It further released 7 512.51 mJ·mg~(-1)(accounting for 41% of the total heat release) in the temperature range of 302-519 ℃. The combustion of A. argyi moxa showed a rapid heat release pattern. The 3-year moxa released a heat of 16 695.28 mJ·mg~(-1)(accounting for 70% of the total heat release) in the temperature range of 140-311 ℃, with an instantaneous power output of 218 mW·mg~(-1). It further released 5 996.95 mJ·mg~(-1)(accounting for 25% of the total heat release) in the temperature range of 311-483 ℃. Combustion parameters such as-R_p,-R_v, D_i, C, and D_b indicated that the combustion heat quality of 3-year moxa was superior to that of 1-year moxa. It exhibited greater combustion heat, heat production efficiency, flammability, mild and sustained burning, and higher instantaneous combustion efficiency. This study utilized scientific data to demonstrate that A. stolonifera could be used as excellent moxa, and the quality of 3-year moxa surpassed that of 1-year moxa. The research results provide a scientific basis for the in-depth development of A. stolonifera moxa and the improvement of moxa quality standards.

[Anti-inflammatory material basis and mechanism of Artemisia stolonifera based on UPLC-Q-TOF-MS combined with network pharmacology and molecular docking].

This study aimed to explore the anti-inflammatory material basis and molecular mechanism of Artemisia stolonifera based on the analysis of the chemical components in different extracted fractions of A. stolonifera and their antioxidant and anti-inflammatory effects in combination with network pharmacology and molecular docking. Thirty-two chemical components were identified from A. stolonifera by ultra-performance liquid chromatography coupled to tandem quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS). Among them, there were 7, 21 and 22 compounds in water, n-butanol and ethyl acetate fractions, respectively. The antio-xidant capacity of different extracted fractions was evaluated by measuring their scavenging ability against 1,1-diphenyl-2-picrylhydrazyl radical 2,2-diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl(DPPH) and 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonic acid)(ABTS) free radicals and total antioxidant capacity [ferric reducing antioxidant power(FRAP) assay]. The inflammatory model of RAW264.7 cells was induced by lipopolysaccharide(LPS), and the levels of nitrite oxide(NO), tumor necrosis factor-α(TNF-α), interleukin-6(IL-6) in the supernatant and the mRNA expression of related inflammatory factors in cells were used to evaluate the anti-inflammatory effects. The results revealed that ethyl acetate fraction of A. stolonifera was the optimal antioxidant and anti-inflammatory fraction. By network pharmacology, it was found that flavonoids such as rhamnazin, eupatilin, jaceosidin, luteolin and nepetin could act on key targets such as TNF, serine/threonine protein kinase 1(AKT1), tumor protein p53(TP53), caspase-3(CASP3) and epidermal growth factor receptor(EGFR), and regulate the phosphatidylinositol-3-kinase-protein kinase B(PI3K-AKT) and mitogen-activated protein kinase(MAPK) signaling pathways to exert the anti-inflammatory effects. Molecular docking further indicated excellent binding properties between the above core components and core targets. This study preliminarily clarified the anti-inflammatory material basis and mechanism of ethyl acetate fraction of A. stolonifera, providing a basis for the follow-up clinical application of A. stolonifera and drug development.

[Effects of shading intensity on growth and quality of Artemisia stolonifera].

The purpose of this study was to analyze the effects of shading intensity on the growth, yield, and quality of Artemisia stolonifera so as to provide references for the artificial cultivation of A. stolonifera. The seedlings of A. stolonifera with consistent growth underwent shading treatment at four shading intensity levels(0, 55%, 85%, and 95%) with different layers of black shading nets. The agronomic indexes, yield, moxa yield, total ash, quality characteristics of moxa during combustion and pyrolysis, main volatile components, flavonoids, and phenolic acids were measured. The results showed that under shading conditions, the stem diameter, leaf width, 5-leaf spacing, branch number, and yield of A. stolonifera decreased significantly, while the plant height, leaf length, leaf number, chlorophyll content, and moxa yield increased first and then decreased with the increase in shading intensity. The burning performance of moxa under natural light was better than that under moderate and severe shading conditions. The content of eucalyptol first increased and then decreased with the increase in shading intensity. The humulene content was negatively correlated with shading intensity. Other major volatile components showed no significant difference under various shading conditions. The content of neochlorogenic acid, cryptochlorogenic acid, isoschaftoside, and isochlorogenic acid B was positively correlated with shading intensity, while the content of chlorogenic acid, isochlorogenic acid A, and isochlorogenic acid C decreased first and then increased with the increase in shading intensity. To sum up, A. stolonifera is a light-loving plant, and shading can greatly reduce the yield, the content of internal components, and the burning performance of moxa. It is the main reason why A. stolonifera is mainly distributed in the forest edge, open forest, roadside, and wasteland grass in the middle and high mountains in the wild. For artificial domestication and cultivation of A. stolonifera, it is better to select plots with sufficient light.