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In this work, we study the unsteady electro‐osmotic flow of fractional viscoelastic fluids in micro‐parallel channels, where the velocity slip effect on the walls is also considered. The analytical solution is obtained through solving the Cauchy momentum equation, together with the linearized Poisson–Boltzmann equation and the fractional Maxwell constitutive equation. The influences of the normalized electrokinetic width K, Deborah number De, slip length L and fractional derivative α on the velocity and volume flow rate are discussed. The results demonstrate that the dimensionless parameters L, De and K all have a promoting effect on the electro‐osmotic flow and resonance behavior of fractional Maxwell fluids. In addition, compared with the classical Maxwell fluid, the microstructure of the fractional Maxwell fluid weakens the resonance behavior. [ABSTRACT FROM AUTHOR]

Skin, as an exposed tissue, often suffers damage after exposure to radiotherapy and accidental events, which may lead to the formation of chronic refractory wounds. However, effective treatment options are usually limited for severe radiation‐induced skin injury (RSI). Platelet‐rich plasma (PRP) has been identified to promote wound healing, but whether a new generation of blood‐derived biomaterial, injectable platelet‐rich fibrin (i‐PRF), is effective in repairing RSI remains unclear. In this study, blood was drawn from humans and Sprague–Dawley rats to prepare PRP and i‐PRF, and the regenerative functions of PRP and i‐PRF were investigated by exposing the dorsal skin of SD rats to local radiation (45 Gy) and exposing HDF‐α cells and human umbilical vein endothelial cells (HUVECs) cells to X‐rays (10 Gy). The healing effect of i‐PRF on RSI was analysed by tube formation assay, cell migration and apoptosis assays, ROS assay, wound healing assay, histological characterisation and immunostaining. The results showed that exposure to high doses of radiation reduced cell viability, increased ROS levels and induced cell apoptosis, thereby causing dorsal trauma of rats. However, both PRP and i‐PRF could resisted RSI, and they were capable of reducing inflammation and promoting angiogenesis and vascular regeneration. i‐PRF has a higher concentration of platelets and platelet‐derived growth factors, which has a more convenient preparation method and better repair effect and possesses a good application prospect for the repair of RSI. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: A novel polyurethane polymer containing perylene diimide (PDI) unit and aniline segment, denoted as PU‐PDI, was designed and synthesized. Their tensile property and photophysical characteristic were investigated using various experimental and theoretical techniques. It is found that the elongation of PU‐PDIs can reach more than 1000%, indicating good tensile performance. Moreover, based on the photoinduced electron transfer mechanism, the aniline segments in polyurethane can quench the auto‐fluorescence of PDI unit to a negligible value, which overcomes the intractable fluorescence drawbacks of conventional colour filters. The non‐emissive characteristic, in combination with the good thermal stability and tensile property of PU‐PDI, provides a feasible design strategy to fabricate optical filters with high display quality. [ABSTRACT FROM AUTHOR]

Objective: To investigate the efficacy and safety of broadband light (BBL) combined with intradermal injection of tranexamic acid for treating melasma. Methods: 120 women with melasma admitted to our hospital from January 2021 to April 2022 were randomly categorized into the following groups: control group, treated with 250 mg tranexamic acid given orally twice daily, except during menstruation; group I, treated with BBL (Sciton, Inc., USA) monthly; group II, received intradermal injections of tranexamic acid monthly; and group III, treated with BBL with intradermal injection of tranexamic acid monthly. Treatment in each group lasted three months. The MASI (Melasma Area Severity Index) and VISIA (Canfield VISIA Complexion Analysis) were used for evaluation. Results: After treatment course, MASI scores and VISIA brown spot and red zone ranking improved in all four groups (p < 0.05). The decrease in MASI scores and improvement rates of VISIA brown spot and red zone rankings were not significantly different among the control group, group I, and group II; however, the decreased MASI scores and improvement rates of VISIA brown spot and red zone rankings were significantly higher in group III than in the other three groups (p < 0.05). Conclusion: The effect of BBL combined with the intradermal injection of TA in the treatment of melasma is remarkable. This combination therapy can be an alternative and effective treatment for managing melasma. [ABSTRACT FROM AUTHOR]

Earthworms modulate carbon and nitrogen cycling in terrestrial ecosystems, but their effect may be compromised by the deposition of pollutants from industrial emissions. However, studies investigating how deposited compounds affect the role of earthworms in carbon cycling such as litter decomposition are lacking, although the interactions of earthworms and deposited compounds are important for understanding the impact of pollutants on ecosystems and the potential of earthworms in bioremediation. We performed a 365‐day in situ litterbag decomposition experiment in a deciduous (Quercus variabilis) and coniferous (Pinus massoniana) forest in southeast China. We manipulated nitrogen (N), sodium (Na), and polycyclic aromatic hydrocarbons (PAHs) as model compounds during litter decomposition with and without earthworms (Eisenia fetida). After one year, N, Na, and PAH all slowed down litter mass loss, with the effects of Na being the strongest. By contrast, E. fetida generally increased litter mass loss, and the positive effects were uniformly maintained irrespective of the type of compounds added. However, the pathways to how earthworms increased litter mass loss varied among the compounds added and the two forests studied. As indicated by structural equation modeling, earthworms mitigated the negative effects of deposited compounds by directly increasing litter mass loss and indirectly increasing soil pH and microbial biomass. Overall, the results indicate that the acceleration of litter mass loss by earthworms is little affected by deposited compounds, and that earthworms have the potential to mitigate negative impacts of pollutants on litter decomposition and ecosystem processes. [ABSTRACT FROM AUTHOR]

Objective: To observe the efficacy of unilateral subcutaneous injection of botulinum toxin A combined with finasteride and minoxidil in the treatment of androgenic alopecia. Methods: Thirty‐seven patients with androgenic alopecia were treated with finasteride and minoxidil as standard therapy and were randomly assigned to subcutaneous injections of botulinum toxin A in one hemisphere of the head at the beginning of a 6‐month treatment. Before treatment, 3 months after treatment, and 6 months after treatment, the patient's head hair growth was photographed and evaluated. Results: After 3 and 6 months of treatment, hair density of the treated androgenic alopecia patients was higher than before treatment (p < 0.05), and the hair density of the botulinum toxin A injection side was higher than that of the control side (p < 0.05). After 6 months of treatment, the response rate of botulinum toxin A combined with finasteride and minoxidil was 77.5%, with no significant side effects observed. Conclusion: Finasteride and minoxidil have a significant effect on androgenic alopecia, and the effect is further increased after combined with botulinum toxin A subcutaneous injection. [ABSTRACT FROM AUTHOR]

Platensimycin (PTM) is an excellent natural product drug lead against various gram‐positive pathogens, including methicillin‐resistant Staphylococcus aureus and vancomycin‐resistant enterococci. In this study, twenty PTM derivatives with varying aminobenzoic acids were semisynthesized. In contrast to all the previous reported inactive aminobenzaote analogues, a few of them showed moderate antibacterial activities against S. aureus. Our study suggested that modification of the conserved aminobenzoic acid remains a viable approach to diversify the PTM scaffold. Platensimycin (PTM, 1) is a potent inhibitor of both bacterial and mammalian fatty acid synthases, and the previous structure‐activity relationship study suggested that its aminobenzoate moiety makes critical interactions with the enzyme active site. In this study, 20 platensimycin analogues with varying aminobenzoic acids were semisynthesized and a few of them showed moderate antibacterial activities against Staphylococcus aureus. These results suggested that modification of the aminobenzoate moiety remains a viable approach to diversify the PTM scaffold. [ABSTRACT FROM AUTHOR]

We extend the symbolic representation to the ring of [ABSTRACT FROM AUTHOR]

Background: Random skin flap is widely used to repair tissue defects; however, it is often accompanied by ischemia and necrosis of the distal flap due to inferior axial vascularity. Even though different drugs, biomaterials, and stem cell therapies have been developed to improve the survival of random flap, evaluating the promotion of flap survival remains a big challenge. Based on successful clinical practice, we designed a "Pingpong racket" shape flap in the rat. Without the predetected blood vessels procedure, the "pingpong racket" flap provides a preferable option to evaluate the function of drugs and biomaterials in promoting flap survival. Materials and methods: "Pingpong racket" dorsal flaps with different pedicle lengths were developed in the rats. The survival area was evaluated by digital photography and computer‐assisted analysis. The quantitative survival area was considered a useful indicator for analyzing drugs' applicability in improving skin flap survival. Results: A new model with a pedicle width of 1 cm and a flap diameter of 3 cm, in which the length of the pedicle could be tuned, was established. No iliolumbar vessels passed through the pedicle. The necrosis ratio (round) of the flap was 29.88% in the 2 cm long pedicle, 74.69% in the 3 cm long pedicle, 95.52% in the 4 cm long pedicle, and in the 5 cm long pedicle; necrotic area could be found in both the round part and in the pedicle. Conclusion: The new 3 cm long pedicle flap is suitable for evaluating the drugs for promoting skin flap survival. Rat dorsal "Pingpong racket" flap can be easily handled, thus avoiding blood vessels' detection. The flap could achieve comparable results to clinical and alleviate the negative influence of the flap's longitudinal contraction. Besides, it is intuitive and aesthetically pleasing. [ABSTRACT FROM AUTHOR]

Summary: The tea plant is an economically important woody beverage crop. The unique taste of tea is evoked by certain metabolites, especially catechin esters, whereas their precise formation mechanism in different cell types remains unclear. Here, a fast protoplast isolation method was established and the transcriptional profiles of 16 977 single cells from 1st and 3rd leaves were investigated. We first identified 79 marker genes based on six isolated tissues and constructed a transcriptome atlas, mapped developmental trajectories and further delineated the distribution of different cell types during leaf differentiation and genes associated with cell fate transformation. Interestingly, eight differently expressed genes were found to co‐exist at four branch points. Genes involved in the biosynthesis of certain metabolites showed cell‐ and development‐specific characteristics. An unexpected catechin ester glycosyltransferase was characterized for the first time in plants by a gene co‐expression network in mesophyll cells. Thus, the first single‐cell transcriptional landscape in woody crop leave was reported and a novel metabolism pathway of catechin esters in plants was discovered. [ABSTRACT FROM AUTHOR]

Four new ent-pimarane diterpenes were isolated from the EtOH extract of Aralia dumetorum, together with three known compounds involving ent-pimar-8(14),15-dien-19-oic acid ( 5), ent-pimar-8(14),15-dien-19-ol ( 6), and ent-kaur-16-en-19-oic acid ( 7). By detailed analyses of the MS, IR, and NMR data, the structures of four new diterpenes were characterized as (5 β,9 β,10 α,13 α)-pimara-6,8(14),15-trien-18-oic acid ( 1), (5 β,7 β,9 β,10 α,13 α)-7-methoxypimara-8(14),15-dien-18-oic acid ( 2), (5 β,9 β,10 α,13 α,14 β)-14-methoxypimara-7,15-dien-18-oic acid ( 3), and (5 β,10 α,13 α,14 α)-14-hydroxypimara-7,9(11),15-trien-18-oic acid ( 4). The cytotoxic activities of compounds 1 - 7 were assayed in vitro through MTT method. [ABSTRACT FROM AUTHOR]

Background: This study was conducted to investigate the effect of P14 promoter aberrant methylation on the biological function of human lung adenocarcinoma cells. Methods: We used nested methylation‐specific PCR (NMSP) to detect the methylation status of the p14ARF promoter region in SPCA1 and BEAS2B cell lines. The experimental groups were treated with 5‐aza‐2′‐deoxycytidine (5‐Aza). Quantitative real‐time PCR, Western blot, flow cytometry, and Cell Counting Kit 8 were used to detect the expression of p14ARF messenger RNA and protein in each group, apoptosis, and cell proliferation inhibition, respectively. Results: NMSP detected that the p14 promoter region of SPCA1 cells has abnormal methylation status. After treatment with 5‐Aza, the expression of p14ARF messenger RNA and protein in SPCA1 cells (P < 0.05) and the inhibition rate of cell proliferation (P < 0.05) were significantly increased, while the apoptosis rate was markedly increased (P < 0.05). However, no differences were observed in BEAS2B cells (P > 0.05). Conclusion: Abnormal methylation of the p14ARF promoter region plays an important role in the development of lung cancer cells. Our results suggest the use of P14 promoter aberrant methylation as a therapeutic target for drug research or to improve the sensitivity of other drugs. [ABSTRACT FROM AUTHOR]

A major gap to understand the effects of plant secondary compounds on litter decomposition in the brown food web is lack of information about how these secondary compounds modify the activities of soil decomposers. To address this question, we conducted an experiment where aqueous extracts and tannins prepared from Pinus massoniana needles were added to soils collected either from P. massoniana (pine soil) or Quercus variabilis (oak soil). Our objective was to investigate the cascading effects of the two compounds on isopod (Armadillidium vulgare) activity and subsequent change in Q. variabilis litter decomposition. We found that in pine soil, both aqueous extracts and tannins (especially at high concentrations) had positive effects on litter decomposition rates when isopods were present. While without isopods, litter decomposition was enhanced only by high concentrations of aqueous extracts, and tannins had no significant effect on decomposition. In oak soil, high concentrations of aqueous extracts and tannins inhibited litter decomposition and soil microbial biomass, regardless of whether isopods were present or not. Low concentrations of aqueous extracts increased litter decomposition rates and soil microbial biomass in oak soil in the absence of isopods. Based on our results, we suggest that the high concentration of secondary compounds in P. massoniana is a key factor influencing the effects of decomposers on litter decomposition rates, and tannins form a major part of secondary compounds. These funding particularly provide insight into form‐ and concentration‐oriented effects of secondary compounds and promote our understanding of litter decomposition and soil nutrient cycling in forest ecosystem. Aqueous extracts of P. massoniana accelerate isopod effect on litter decomposition in soils beneath conifer. Tannins inhibit litter decomposition in soils beneath broadleaf but not conifer. Soil organisms in soils beneath conifer can well adapt to the adverse effect of tannins. [ABSTRACT FROM AUTHOR]

Four new ent-pimarane diterpenes (I)-(IV) are isolated from the roots of Aralia dumetorum together with three known compounds. [ABSTRACT FROM AUTHOR]

The Wenchuan earthquake induced large amounts of debris flows and catastrophic incidents triggered by subsequent rainstorms occurred frequently in the past 6 rainy seasons, and thus resulted in serious casualties, huge economic loss and long-term impact. In this paper, post-seismic debris flows distributed in 10 Wenchuan earthquake extremely stricken counties were verified and debris flow database consisting of 609 debris flows was established based on detailed investigation organized by Land and Resources Department of Sichuan Province. Combined with database and related studies, the impact of Wenchuan earthquake on debris flows was analyzed. And then variation of formation conditions including rainfall threshold and landform condition was analyzed by contrasting pre-seismic and post-seismic debris flows. Followed are some typical viewpoints on initiation mechanism of post-seismic debris flows. In the end of this paper, characteristics of post-seismic debris flows triggered by subsequent rainstorms were comprehensively summarized, such as regional group occurrence, high frequency, high viscosity, chain effect, huge dynamics, large scale and long duration. We hope this paper will be helpful in understanding the formation mechanism, disaster characteristics and prevention countermeasures of post-seismic debris flows in Wenchuan earthquake extremely stricken areas. [ABSTRACT FROM AUTHOR]

Nonivamide, a synthetic derivate of natural capsaicin, has an effective antifouling activity. However, the poor understanding of the toxicity mechanism limits the application of nonivamide in antifouling paints. The present study investigated the inhibitory effects and toxicity mechanism of nonivamide on Phaeodactylum tricornutum. Under a 1.5 × 105 cells/ml of initial algal density (IAD), the effective concentration causing 50% inhibition at 4- d (4 d-EC50) value of nonivamide was 5.1 mg/L. Reactive oxygen species (ROS) level was significantly increased in nonivamide-treated algae. Algal antioxidants, including catalases (CAT), peroxidases (POD), superoxide dismutases (SOD), and glutathione (GSH), were all stimulated by the ROS burst. The excessive ROS substances led to the loss of algal photosynthetic pigments and also damage to the integrity of the lipid membrane. Furthermore, ROS-related genes, including psbA, psbD, psaB, rbcL, nad1, and cob, were found to be suppressed in the chloroplasts and mitochondria of nonivamide-treated algae, and the concentration of cytoplasmic Ca2+, an important regulator of chloroplast and mitochondrion, was elevated. The present study demonstrates that nonivamide could cause peroxidative damages to P. tricornutum by inducing ROS overproduction, which may be initiated by the suppression of ROS-related genes in algal chloroplasts and mitochondria. Environ. Toxicol. Chem. 2013;32:802-809. © 2013 SETAC [ABSTRACT FROM AUTHOR]

Creating a soil habitat is the first step to manage soil health for long‐term soil quality and output. This means using soil management methods that lessen the soil uproar. An experiment was established in 2016 and 2017 on a middle term (7 years) consistent tillage method in typical Latosolic red soil of Southern China to access the effects of four treatments: subsoiling (SS), two passes of rotary tillage (2RT), two passes of rotary tillage + subsoiling (2RTSS), and zero tillage (ZT), on soil organic carbon, soil total nitrogen, soil biological activities (bacteria, fungi, actinomycetes, urease, catalase, and phosphatase), and maize grain yield. The results showed that mean SOC, total N, biological activities, and maize grain yields were affected significantly (p < 0.05) by tillage methods. Compared with SS, 2RT, and 2RTSS, ZT had higher SOC, total N, soil bacteria, and soil actinomycetes in the 0–40 cm soil depth. The highest levels of fungi, urease, catalase, and phosphatase were recorded under SS in the 0–40 cm soil depth. Average maize grain yield of 7.37 ton/ha (9.81%) was recorded under SS compared to under ZT. Overall, we conclude that SS could be adopted as a promising soil management method for soil health, quality, and productivity resulting in a sustainable agricultural system. [ABSTRACT FROM AUTHOR]